Merge commit 'v2.6.32-rc5' into perf/probes

Conflicts:
	kernel/trace/trace_event_profile.c

Merge reason: update to -rc5 and resolve conflict.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

212 files changed, 7542 insertions, 4371 deletions

diff --git a/fs/9p/Kconfig b/fs/9p/Kconfig
index 74e0723..7952337 100644
--- a/fs/9p/Kconfig
+++ b/fs/9p/Kconfig
@@ -8,3 +8,12 @@ config 9P_FS
 	  See <http://v9fs.sf.net> for more information.
 
 	  If unsure, say N.
+
+config 9P_FSCACHE
+	bool "Enable 9P client caching support (EXPERIMENTAL)"
+	depends on EXPERIMENTAL
+	depends on 9P_FS=m && FSCACHE || 9P_FS=y && FSCACHE=y
+	help
+	  Choose Y here to enable persistent, read-only local
+	  caching support for 9p clients using FS-Cache
+
diff --git a/fs/9p/Makefile b/fs/9p/Makefile
index bc7f0d1..1a940ec 100644
--- a/fs/9p/Makefile
+++ b/fs/9p/Makefile
@@ -8,5 +8,6 @@ obj-$(CONFIG_9P_FS) := 9p.o
 	vfs_dir.o \
 	vfs_dentry.o \
 	v9fs.o \
-	fid.o \
+	fid.o
 
+9p-$(CONFIG_9P_FSCACHE) += cache.o
diff --git a/fs/9p/cache.c b/fs/9p/cache.c
new file mode 100644
index 0000000..51c94e2
--- /dev/null
+++ b/fs/9p/cache.c
@@ -0,0 +1,474 @@
+/*
+ * V9FS cache definitions.
+ *
+ *  Copyright (C) 2009 by Abhishek Kulkarni <adkulkar@umail.iu.edu>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#include <linux/jiffies.h>
+#include <linux/file.h>
+#include <linux/stat.h>
+#include <linux/sched.h>
+#include <linux/fs.h>
+#include <net/9p/9p.h>
+
+#include "v9fs.h"
+#include "cache.h"
+
+#define CACHETAG_LEN  11
+
+struct kmem_cache *vcookie_cache;
+
+struct fscache_netfs v9fs_cache_netfs = {
+	.name 		= "9p",
+	.version 	= 0,
+};
+
+static void init_once(void *foo)
+{
+	struct v9fs_cookie *vcookie = (struct v9fs_cookie *) foo;
+	vcookie->fscache = NULL;
+	vcookie->qid = NULL;
+	inode_init_once(&vcookie->inode);
+}
+
+/**
+ * v9fs_init_vcookiecache - initialize a cache for vcookies to maintain
+ *			    vcookie to inode mapping
+ *
+ * Returns 0 on success.
+ */
+
+static int v9fs_init_vcookiecache(void)
+{
+	vcookie_cache = kmem_cache_create("vcookie_cache",
+					  sizeof(struct v9fs_cookie),
+					  0, (SLAB_RECLAIM_ACCOUNT|
+					      SLAB_MEM_SPREAD),
+					  init_once);
+	if (!vcookie_cache)
+		return -ENOMEM;
+
+	return 0;
+}
+
+/**
+ * v9fs_destroy_vcookiecache - destroy the cache of vcookies
+ *
+ */
+
+static void v9fs_destroy_vcookiecache(void)
+{
+	kmem_cache_destroy(vcookie_cache);
+}
+
+int __v9fs_cache_register(void)
+{
+	int ret;
+	ret = v9fs_init_vcookiecache();
+	if (ret < 0)
+		return ret;
+
+	return fscache_register_netfs(&v9fs_cache_netfs);
+}
+
+void __v9fs_cache_unregister(void)
+{
+	v9fs_destroy_vcookiecache();
+	fscache_unregister_netfs(&v9fs_cache_netfs);
+}
+
+/**
+ * v9fs_random_cachetag - Generate a random tag to be associated
+ *			  with a new cache session.
+ *
+ * The value of jiffies is used for a fairly randomly cache tag.
+ */
+
+static
+int v9fs_random_cachetag(struct v9fs_session_info *v9ses)
+{
+	v9ses->cachetag = kmalloc(CACHETAG_LEN, GFP_KERNEL);
+	if (!v9ses->cachetag)
+		return -ENOMEM;
+
+	return scnprintf(v9ses->cachetag, CACHETAG_LEN, "%lu", jiffies);
+}
+
+static uint16_t v9fs_cache_session_get_key(const void *cookie_netfs_data,
+					   void *buffer, uint16_t bufmax)
+{
+	struct v9fs_session_info *v9ses;
+	uint16_t klen = 0;
+
+	v9ses = (struct v9fs_session_info *)cookie_netfs_data;
+	P9_DPRINTK(P9_DEBUG_FSC, "session %p buf %p size %u", v9ses,
+		   buffer, bufmax);
+
+	if (v9ses->cachetag)
+		klen = strlen(v9ses->cachetag);
+
+	if (klen > bufmax)
+		return 0;
+
+	memcpy(buffer, v9ses->cachetag, klen);
+	P9_DPRINTK(P9_DEBUG_FSC, "cache session tag %s", v9ses->cachetag);
+	return klen;
+}
+
+const struct fscache_cookie_def v9fs_cache_session_index_def = {
+	.name 		= "9P.session",
+	.type 		= FSCACHE_COOKIE_TYPE_INDEX,
+	.get_key 	= v9fs_cache_session_get_key,
+};
+
+void v9fs_cache_session_get_cookie(struct v9fs_session_info *v9ses)
+{
+	/* If no cache session tag was specified, we generate a random one. */
+	if (!v9ses->cachetag)
+		v9fs_random_cachetag(v9ses);
+
+	v9ses->fscache = fscache_acquire_cookie(v9fs_cache_netfs.primary_index,
+						&v9fs_cache_session_index_def,
+						v9ses);
+	P9_DPRINTK(P9_DEBUG_FSC, "session %p get cookie %p", v9ses,
+		   v9ses->fscache);
+}
+
+void v9fs_cache_session_put_cookie(struct v9fs_session_info *v9ses)
+{
+	P9_DPRINTK(P9_DEBUG_FSC, "session %p put cookie %p", v9ses,
+		   v9ses->fscache);
+	fscache_relinquish_cookie(v9ses->fscache, 0);
+	v9ses->fscache = NULL;
+}
+
+
+static uint16_t v9fs_cache_inode_get_key(const void *cookie_netfs_data,
+					 void *buffer, uint16_t bufmax)
+{
+	const struct v9fs_cookie *vcookie = cookie_netfs_data;
+	memcpy(buffer, &vcookie->qid->path, sizeof(vcookie->qid->path));
+
+	P9_DPRINTK(P9_DEBUG_FSC, "inode %p get key %llu", &vcookie->inode,
+		   vcookie->qid->path);
+	return sizeof(vcookie->qid->path);
+}
+
+static void v9fs_cache_inode_get_attr(const void *cookie_netfs_data,
+				      uint64_t *size)
+{
+	const struct v9fs_cookie *vcookie = cookie_netfs_data;
+	*size = i_size_read(&vcookie->inode);
+
+	P9_DPRINTK(P9_DEBUG_FSC, "inode %p get attr %llu", &vcookie->inode,
+		   *size);
+}
+
+static uint16_t v9fs_cache_inode_get_aux(const void *cookie_netfs_data,
+					 void *buffer, uint16_t buflen)
+{
+	const struct v9fs_cookie *vcookie = cookie_netfs_data;
+	memcpy(buffer, &vcookie->qid->version, sizeof(vcookie->qid->version));
+
+	P9_DPRINTK(P9_DEBUG_FSC, "inode %p get aux %u", &vcookie->inode,
+		   vcookie->qid->version);
+	return sizeof(vcookie->qid->version);
+}
+
+static enum
+fscache_checkaux v9fs_cache_inode_check_aux(void *cookie_netfs_data,
+					    const void *buffer,
+					    uint16_t buflen)
+{
+	const struct v9fs_cookie *vcookie = cookie_netfs_data;
+
+	if (buflen != sizeof(vcookie->qid->version))
+		return FSCACHE_CHECKAUX_OBSOLETE;
+
+	if (memcmp(buffer, &vcookie->qid->version,
+		   sizeof(vcookie->qid->version)))
+		return FSCACHE_CHECKAUX_OBSOLETE;
+
+	return FSCACHE_CHECKAUX_OKAY;
+}
+
+static void v9fs_cache_inode_now_uncached(void *cookie_netfs_data)
+{
+	struct v9fs_cookie *vcookie = cookie_netfs_data;
+	struct pagevec pvec;
+	pgoff_t first;
+	int loop, nr_pages;
+
+	pagevec_init(&pvec, 0);
+	first = 0;
+
+	for (;;) {
+		nr_pages = pagevec_lookup(&pvec, vcookie->inode.i_mapping,
+					  first,
+					  PAGEVEC_SIZE - pagevec_count(&pvec));
+		if (!nr_pages)
+			break;
+
+		for (loop = 0; loop < nr_pages; loop++)
+			ClearPageFsCache(pvec.pages[loop]);
+
+		first = pvec.pages[nr_pages - 1]->index + 1;
+
+		pvec.nr = nr_pages;
+		pagevec_release(&pvec);
+		cond_resched();
+	}
+}
+
+const struct fscache_cookie_def v9fs_cache_inode_index_def = {
+	.name		= "9p.inode",
+	.type		= FSCACHE_COOKIE_TYPE_DATAFILE,
+	.get_key	= v9fs_cache_inode_get_key,
+	.get_attr	= v9fs_cache_inode_get_attr,
+	.get_aux	= v9fs_cache_inode_get_aux,
+	.check_aux	= v9fs_cache_inode_check_aux,
+	.now_uncached	= v9fs_cache_inode_now_uncached,
+};
+
+void v9fs_cache_inode_get_cookie(struct inode *inode)
+{
+	struct v9fs_cookie *vcookie;
+	struct v9fs_session_info *v9ses;
+
+	if (!S_ISREG(inode->i_mode))
+		return;
+
+	vcookie = v9fs_inode2cookie(inode);
+	if (vcookie->fscache)
+		return;
+
+	v9ses = v9fs_inode2v9ses(inode);
+	vcookie->fscache = fscache_acquire_cookie(v9ses->fscache,
+						  &v9fs_cache_inode_index_def,
+						  vcookie);
+
+	P9_DPRINTK(P9_DEBUG_FSC, "inode %p get cookie %p", inode,
+		   vcookie->fscache);
+}
+
+void v9fs_cache_inode_put_cookie(struct inode *inode)
+{
+	struct v9fs_cookie *vcookie = v9fs_inode2cookie(inode);
+
+	if (!vcookie->fscache)
+		return;
+	P9_DPRINTK(P9_DEBUG_FSC, "inode %p put cookie %p", inode,
+		   vcookie->fscache);
+
+	fscache_relinquish_cookie(vcookie->fscache, 0);
+	vcookie->fscache = NULL;
+}
+
+void v9fs_cache_inode_flush_cookie(struct inode *inode)
+{
+	struct v9fs_cookie *vcookie = v9fs_inode2cookie(inode);
+
+	if (!vcookie->fscache)
+		return;
+	P9_DPRINTK(P9_DEBUG_FSC, "inode %p flush cookie %p", inode,
+		   vcookie->fscache);
+
+	fscache_relinquish_cookie(vcookie->fscache, 1);
+	vcookie->fscache = NULL;
+}
+
+void v9fs_cache_inode_set_cookie(struct inode *inode, struct file *filp)
+{
+	struct v9fs_cookie *vcookie = v9fs_inode2cookie(inode);
+	struct p9_fid *fid;
+
+	if (!vcookie->fscache)
+		return;
+
+	spin_lock(&vcookie->lock);
+	fid = filp->private_data;
+	if ((filp->f_flags & O_ACCMODE) != O_RDONLY)
+		v9fs_cache_inode_flush_cookie(inode);
+	else
+		v9fs_cache_inode_get_cookie(inode);
+
+	spin_unlock(&vcookie->lock);
+}
+
+void v9fs_cache_inode_reset_cookie(struct inode *inode)
+{
+	struct v9fs_cookie *vcookie = v9fs_inode2cookie(inode);
+	struct v9fs_session_info *v9ses;
+	struct fscache_cookie *old;
+
+	if (!vcookie->fscache)
+		return;
+
+	old = vcookie->fscache;
+
+	spin_lock(&vcookie->lock);
+	fscache_relinquish_cookie(vcookie->fscache, 1);
+
+	v9ses = v9fs_inode2v9ses(inode);
+	vcookie->fscache = fscache_acquire_cookie(v9ses->fscache,
+						  &v9fs_cache_inode_index_def,
+						  vcookie);
+
+	P9_DPRINTK(P9_DEBUG_FSC, "inode %p revalidating cookie old %p new %p",
+		   inode, old, vcookie->fscache);
+
+	spin_unlock(&vcookie->lock);
+}
+
+int __v9fs_fscache_release_page(struct page *page, gfp_t gfp)
+{
+	struct inode *inode = page->mapping->host;
+	struct v9fs_cookie *vcookie = v9fs_inode2cookie(inode);
+
+	BUG_ON(!vcookie->fscache);
+
+	if (PageFsCache(page)) {
+		if (fscache_check_page_write(vcookie->fscache, page)) {
+			if (!(gfp & __GFP_WAIT))
+				return 0;
+			fscache_wait_on_page_write(vcookie->fscache, page);
+		}
+
+		fscache_uncache_page(vcookie->fscache, page);
+		ClearPageFsCache(page);
+	}
+
+	return 1;
+}
+
+void __v9fs_fscache_invalidate_page(struct page *page)
+{
+	struct inode *inode = page->mapping->host;
+	struct v9fs_cookie *vcookie = v9fs_inode2cookie(inode);
+
+	BUG_ON(!vcookie->fscache);
+
+	if (PageFsCache(page)) {
+		fscache_wait_on_page_write(vcookie->fscache, page);
+		BUG_ON(!PageLocked(page));
+		fscache_uncache_page(vcookie->fscache, page);
+		ClearPageFsCache(page);
+	}
+}
+
+static void v9fs_vfs_readpage_complete(struct page *page, void *data,
+				       int error)
+{
+	if (!error)
+		SetPageUptodate(page);
+
+	unlock_page(page);
+}
+
+/**
+ * __v9fs_readpage_from_fscache - read a page from cache
+ *
+ * Returns 0 if the pages are in cache and a BIO is submitted,
+ * 1 if the pages are not in cache and -error otherwise.
+ */
+
+int __v9fs_readpage_from_fscache(struct inode *inode, struct page *page)
+{
+	int ret;
+	const struct v9fs_cookie *vcookie = v9fs_inode2cookie(inode);
+
+	P9_DPRINTK(P9_DEBUG_FSC, "inode %p page %p", inode, page);
+	if (!vcookie->fscache)
+		return -ENOBUFS;
+
+	ret = fscache_read_or_alloc_page(vcookie->fscache,
+					 page,
+					 v9fs_vfs_readpage_complete,
+					 NULL,
+					 GFP_KERNEL);
+	switch (ret) {
+	case -ENOBUFS:
+	case -ENODATA:
+		P9_DPRINTK(P9_DEBUG_FSC, "page/inode not in cache %d", ret);
+		return 1;
+	case 0:
+		P9_DPRINTK(P9_DEBUG_FSC, "BIO submitted");
+		return ret;
+	default:
+		P9_DPRINTK(P9_DEBUG_FSC, "ret %d", ret);
+		return ret;
+	}
+}
+
+/**
+ * __v9fs_readpages_from_fscache - read multiple pages from cache
+ *
+ * Returns 0 if the pages are in cache and a BIO is submitted,
+ * 1 if the pages are not in cache and -error otherwise.
+ */
+
+int __v9fs_readpages_from_fscache(struct inode *inode,
+				  struct address_space *mapping,
+				  struct list_head *pages,
+				  unsigned *nr_pages)
+{
+	int ret;
+	const struct v9fs_cookie *vcookie = v9fs_inode2cookie(inode);
+
+	P9_DPRINTK(P9_DEBUG_FSC, "inode %p pages %u", inode, *nr_pages);
+	if (!vcookie->fscache)
+		return -ENOBUFS;
+
+	ret = fscache_read_or_alloc_pages(vcookie->fscache,
+					  mapping, pages, nr_pages,
+					  v9fs_vfs_readpage_complete,
+					  NULL,
+					  mapping_gfp_mask(mapping));
+	switch (ret) {
+	case -ENOBUFS:
+	case -ENODATA:
+		P9_DPRINTK(P9_DEBUG_FSC, "pages/inodes not in cache %d", ret);
+		return 1;
+	case 0:
+		BUG_ON(!list_empty(pages));
+		BUG_ON(*nr_pages != 0);
+		P9_DPRINTK(P9_DEBUG_FSC, "BIO submitted");
+		return ret;
+	default:
+		P9_DPRINTK(P9_DEBUG_FSC, "ret %d", ret);
+		return ret;
+	}
+}
+
+/**
+ * __v9fs_readpage_to_fscache - write a page to the cache
+ *
+ */
+
+void __v9fs_readpage_to_fscache(struct inode *inode, struct page *page)
+{
+	int ret;
+	const struct v9fs_cookie *vcookie = v9fs_inode2cookie(inode);
+
+	P9_DPRINTK(P9_DEBUG_FSC, "inode %p page %p", inode, page);
+	ret = fscache_write_page(vcookie->fscache, page, GFP_KERNEL);
+	P9_DPRINTK(P9_DEBUG_FSC, "ret =  %d", ret);
+	if (ret != 0)
+		v9fs_uncache_page(inode, page);
+}
diff --git a/fs/9p/cache.h b/fs/9p/cache.h
new file mode 100644
index 0000000..a94192b
--- /dev/null
+++ b/fs/9p/cache.h
@@ -0,0 +1,176 @@
+/*
+ * V9FS cache definitions.
+ *
+ *  Copyright (C) 2009 by Abhishek Kulkarni <adkulkar@umail.iu.edu>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2
+ *  as published by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to:
+ *  Free Software Foundation
+ *  51 Franklin Street, Fifth Floor
+ *  Boston, MA  02111-1301  USA
+ *
+ */
+
+#ifndef _9P_CACHE_H
+#ifdef CONFIG_9P_FSCACHE
+#include <linux/fscache.h>
+#include <linux/spinlock.h>
+
+extern struct kmem_cache *vcookie_cache;
+
+struct v9fs_cookie {
+	spinlock_t lock;
+	struct inode inode;
+	struct fscache_cookie *fscache;
+	struct p9_qid *qid;
+};
+
+static inline struct v9fs_cookie *v9fs_inode2cookie(const struct inode *inode)
+{
+	return container_of(inode, struct v9fs_cookie, inode);
+}
+
+extern struct fscache_netfs v9fs_cache_netfs;
+extern const struct fscache_cookie_def v9fs_cache_session_index_def;
+extern const struct fscache_cookie_def v9fs_cache_inode_index_def;
+
+extern void v9fs_cache_session_get_cookie(struct v9fs_session_info *v9ses);
+extern void v9fs_cache_session_put_cookie(struct v9fs_session_info *v9ses);
+
+extern void v9fs_cache_inode_get_cookie(struct inode *inode);
+extern void v9fs_cache_inode_put_cookie(struct inode *inode);
+extern void v9fs_cache_inode_flush_cookie(struct inode *inode);
+extern void v9fs_cache_inode_set_cookie(struct inode *inode, struct file *filp);
+extern void v9fs_cache_inode_reset_cookie(struct inode *inode);
+
+extern int __v9fs_cache_register(void);
+extern void __v9fs_cache_unregister(void);
+
+extern int __v9fs_fscache_release_page(struct page *page, gfp_t gfp);
+extern void __v9fs_fscache_invalidate_page(struct page *page);
+extern int __v9fs_readpage_from_fscache(struct inode *inode,
+					struct page *page);
+extern int __v9fs_readpages_from_fscache(struct inode *inode,
+					 struct address_space *mapping,
+					 struct list_head *pages,
+					 unsigned *nr_pages);
+extern void __v9fs_readpage_to_fscache(struct inode *inode, struct page *page);
+
+
+/**
+ * v9fs_cache_register - Register v9fs file system with the cache
+ */
+static inline int v9fs_cache_register(void)
+{
+	return __v9fs_cache_register();
+}
+
+/**
+ * v9fs_cache_unregister - Unregister v9fs from the cache
+ */
+static inline void v9fs_cache_unregister(void)
+{
+	__v9fs_cache_unregister();
+}
+
+static inline int v9fs_fscache_release_page(struct page *page,
+					    gfp_t gfp)
+{
+	return __v9fs_fscache_release_page(page, gfp);
+}
+
+static inline void v9fs_fscache_invalidate_page(struct page *page)
+{
+	__v9fs_fscache_invalidate_page(page);
+}
+
+static inline int v9fs_readpage_from_fscache(struct inode *inode,
+					     struct page *page)
+{
+	return __v9fs_readpage_from_fscache(inode, page);
+}
+
+static inline int v9fs_readpages_from_fscache(struct inode *inode,
+					      struct address_space *mapping,
+					      struct list_head *pages,
+					      unsigned *nr_pages)
+{
+	return __v9fs_readpages_from_fscache(inode, mapping, pages,
+					     nr_pages);
+}
+
+static inline void v9fs_readpage_to_fscache(struct inode *inode,
+					    struct page *page)
+{
+	if (PageFsCache(page))
+		__v9fs_readpage_to_fscache(inode, page);
+}
+
+static inline void v9fs_uncache_page(struct inode *inode, struct page *page)
+{
+	struct v9fs_cookie *vcookie = v9fs_inode2cookie(inode);
+	fscache_uncache_page(vcookie->fscache, page);
+	BUG_ON(PageFsCache(page));
+}
+
+static inline void v9fs_vcookie_set_qid(struct inode *inode,
+					struct p9_qid *qid)
+{
+	struct v9fs_cookie *vcookie = v9fs_inode2cookie(inode);
+	spin_lock(&vcookie->lock);
+	vcookie->qid = qid;
+	spin_unlock(&vcookie->lock);
+}
+
+#else /* CONFIG_9P_FSCACHE */
+
+static inline int v9fs_cache_register(void)
+{
+	return 1;
+}
+
+static inline void v9fs_cache_unregister(void) {}
+
+static inline int v9fs_fscache_release_page(struct page *page,
+					    gfp_t gfp) {
+	return 1;
+}
+
+static inline void v9fs_fscache_invalidate_page(struct page *page) {}
+
+static inline int v9fs_readpage_from_fscache(struct inode *inode,
+					     struct page *page)
+{
+	return -ENOBUFS;
+}
+
+static inline int v9fs_readpages_from_fscache(struct inode *inode,
+					      struct address_space *mapping,
+					      struct list_head *pages,
+					      unsigned *nr_pages)
+{
+	return -ENOBUFS;
+}
+
+static inline void v9fs_readpage_to_fscache(struct inode *inode,
+					    struct page *page)
+{}
+
+static inline void v9fs_uncache_page(struct inode *inode, struct page *page)
+{}
+
+static inline void v9fs_vcookie_set_qid(struct inode *inode,
+					struct p9_qid *qid)
+{}
+
+#endif /* CONFIG_9P_FSCACHE */
+#endif /* _9P_CACHE_H */
diff --git a/fs/9p/v9fs.c b/fs/9p/v9fs.c
index f7003cf..cf62b05 100644
--- a/fs/9p/v9fs.c
+++ b/fs/9p/v9fs.c
@@ -34,21 +34,25 @@
 #include <net/9p/transport.h>
 #include "v9fs.h"
 #include "v9fs_vfs.h"
+#include "cache.h"
+
+static DEFINE_SPINLOCK(v9fs_sessionlist_lock);
+static LIST_HEAD(v9fs_sessionlist);
 
 /*
-  * Option Parsing (code inspired by NFS code)
-  *  NOTE: each transport will parse its own options
-  */
+ * Option Parsing (code inspired by NFS code)
+ *  NOTE: each transport will parse its own options
+ */
 
 enum {
 	/* Options that take integer arguments */
 	Opt_debug, Opt_dfltuid, Opt_dfltgid, Opt_afid,
 	/* String options */
-	Opt_uname, Opt_remotename, Opt_trans,
+	Opt_uname, Opt_remotename, Opt_trans, Opt_cache, Opt_cachetag,
 	/* Options that take no arguments */
 	Opt_nodevmap,
 	/* Cache options */
-	Opt_cache_loose,
+	Opt_cache_loose, Opt_fscache,
 	/* Access options */
 	Opt_access,
 	/* Error token */
@@ -63,8 +67,10 @@ static const match_table_t tokens = {
 	{Opt_uname, "uname=%s"},
 	{Opt_remotename, "aname=%s"},
 	{Opt_nodevmap, "nodevmap"},
-	{Opt_cache_loose, "cache=loose"},
+	{Opt_cache, "cache=%s"},
 	{Opt_cache_loose, "loose"},
+	{Opt_fscache, "fscache"},
+	{Opt_cachetag, "cachetag=%s"},
 	{Opt_access, "access=%s"},
 	{Opt_err, NULL}
 };
@@ -89,16 +95,16 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
 	v9ses->afid = ~0;
 	v9ses->debug = 0;
 	v9ses->cache = 0;
+#ifdef CONFIG_9P_FSCACHE
+	v9ses->cachetag = NULL;
+#endif
 
 	if (!opts)
 		return 0;
 
 	options = kstrdup(opts, GFP_KERNEL);
-	if (!options) {
-		P9_DPRINTK(P9_DEBUG_ERROR,
-			   "failed to allocate copy of option string\n");
-		return -ENOMEM;
-	}
+	if (!options)
+		goto fail_option_alloc;
 
 	while ((p = strsep(&options, ",")) != NULL) {
 		int token;
@@ -143,16 +149,33 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
 		case Opt_cache_loose:
 			v9ses->cache = CACHE_LOOSE;
 			break;
+		case Opt_fscache:
+			v9ses->cache = CACHE_FSCACHE;
+			break;
+		case Opt_cachetag:
+#ifdef CONFIG_9P_FSCACHE
+			v9ses->cachetag = match_strdup(&args[0]);
+#endif
+			break;
+		case Opt_cache:
+			s = match_strdup(&args[0]);
+			if (!s)
+				goto fail_option_alloc;
+
+			if (strcmp(s, "loose") == 0)
+				v9ses->cache = CACHE_LOOSE;
+			else if (strcmp(s, "fscache") == 0)
+				v9ses->cache = CACHE_FSCACHE;
+			else
+				v9ses->cache = CACHE_NONE;
+			kfree(s);
+			break;
 
 		case Opt_access:
 			s = match_strdup(&args[0]);
-			if (!s) {
-				P9_DPRINTK(P9_DEBUG_ERROR,
-					   "failed to allocate copy"
-					   " of option argument\n");
-				ret = -ENOMEM;
-				break;
-			}
+			if (!s)
+				goto fail_option_alloc;
+
 			v9ses->flags &= ~V9FS_ACCESS_MASK;
 			if (strcmp(s, "user") == 0)
 				v9ses->flags |= V9FS_ACCESS_USER;
@@ -173,6 +196,11 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
 	}
 	kfree(options);
 	return ret;
+
+fail_option_alloc:
+	P9_DPRINTK(P9_DEBUG_ERROR,
+		   "failed to allocate copy of option argument\n");
+	return -ENOMEM;
 }
 
 /**
@@ -200,6 +228,10 @@ struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
 		return ERR_PTR(-ENOMEM);
 	}
 
+	spin_lock(&v9fs_sessionlist_lock);
+	list_add(&v9ses->slist, &v9fs_sessionlist);
+	spin_unlock(&v9fs_sessionlist_lock);
+
 	v9ses->flags = V9FS_EXTENDED | V9FS_ACCESS_USER;
 	strcpy(v9ses->uname, V9FS_DEFUSER);
 	strcpy(v9ses->aname, V9FS_DEFANAME);
@@ -249,6 +281,11 @@ struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
 	else
 		fid->uid = ~0;
 
+#ifdef CONFIG_9P_FSCACHE
+	/* register the session for caching */
+	v9fs_cache_session_get_cookie(v9ses);
+#endif
+
 	return fid;
 
 error:
@@ -268,8 +305,18 @@ void v9fs_session_close(struct v9fs_session_info *v9ses)
 		v9ses->clnt = NULL;
 	}
 
+#ifdef CONFIG_9P_FSCACHE
+	if (v9ses->fscache) {
+		v9fs_cache_session_put_cookie(v9ses);
+		kfree(v9ses->cachetag);
+	}
+#endif
 	__putname(v9ses->uname);
 	__putname(v9ses->aname);
+
+	spin_lock(&v9fs_sessionlist_lock);
+	list_del(&v9ses->slist);
+	spin_unlock(&v9fs_sessionlist_lock);
 }
 
 /**
@@ -286,25 +333,132 @@ void v9fs_session_cancel(struct v9fs_session_info *v9ses) {
 
 extern int v9fs_error_init(void);
 
+static struct kobject *v9fs_kobj;
+
+#ifdef CONFIG_9P_FSCACHE
 /**
- * v9fs_init - Initialize module
+ * caches_show - list caches associated with a session
+ *
+ * Returns the size of buffer written.
+ */
+
+static ssize_t caches_show(struct kobject *kobj,
+			   struct kobj_attribute *attr,
+			   char *buf)
+{
+	ssize_t n = 0, count = 0, limit = PAGE_SIZE;
+	struct v9fs_session_info *v9ses;
+
+	spin_lock(&v9fs_sessionlist_lock);
+	list_for_each_entry(v9ses, &v9fs_sessionlist, slist) {
+		if (v9ses->cachetag) {
+			n = snprintf(buf, limit, "%s\n", v9ses->cachetag);
+			if (n < 0) {
+				count = n;
+				break;
+			}
+
+			count += n;
+			limit -= n;
+		}
+	}
+
+	spin_unlock(&v9fs_sessionlist_lock);
+	return count;
+}
+
+static struct kobj_attribute v9fs_attr_cache = __ATTR_RO(caches);
+#endif /* CONFIG_9P_FSCACHE */
+
+static struct attribute *v9fs_attrs[] = {
+#ifdef CONFIG_9P_FSCACHE
+	&v9fs_attr_cache.attr,
+#endif
+	NULL,
+};
+
+static struct attribute_group v9fs_attr_group = {
+	.attrs = v9fs_attrs,
+};
+
+/**
+ * v9fs_sysfs_init - Initialize the v9fs sysfs interface
+ *
+ */
+
+static int v9fs_sysfs_init(void)
+{
+	v9fs_kobj = kobject_create_and_add("9p", fs_kobj);
+	if (!v9fs_kobj)
+		return -ENOMEM;
+
+	if (sysfs_create_group(v9fs_kobj, &v9fs_attr_group)) {
+		kobject_put(v9fs_kobj);
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+/**
+ * v9fs_sysfs_cleanup - Unregister the v9fs sysfs interface
+ *
+ */
+
+static void v9fs_sysfs_cleanup(void)
+{
+	sysfs_remove_group(v9fs_kobj, &v9fs_attr_group);
+	kobject_put(v9fs_kobj);
+}
+
+/**
+ * init_v9fs - Initialize module
  *
  */
 
 static int __init init_v9fs(void)
 {
+	int err;
 	printk(KERN_INFO "Installing v9fs 9p2000 file system support\n");
 	/* TODO: Setup list of registered trasnport modules */
-	return register_filesystem(&v9fs_fs_type);
+	err = register_filesystem(&v9fs_fs_type);
+	if (err < 0) {
+		printk(KERN_ERR "Failed to register filesystem\n");
+		return err;
+	}
+
+	err = v9fs_cache_register();
+	if (err < 0) {
+		printk(KERN_ERR "Failed to register v9fs for caching\n");
+		goto out_fs_unreg;
+	}
+
+	err = v9fs_sysfs_init();
+	if (err < 0) {
+		printk(KERN_ERR "Failed to register with sysfs\n");
+		goto out_sysfs_cleanup;
+	}
+
+	return 0;
+
+out_sysfs_cleanup:
+	v9fs_sysfs_cleanup();
+
+out_fs_unreg:
+	unregister_filesystem(&v9fs_fs_type);
+
+	return err;
 }
 
 /**
- * v9fs_init - shutdown module
+ * exit_v9fs - shutdown module
  *
  */
 
 static void __exit exit_v9fs(void)
 {
+	v9fs_sysfs_cleanup();
+	v9fs_cache_unregister();
 	unregister_filesystem(&v9fs_fs_type);
 }
 
diff --git a/fs/9p/v9fs.h b/fs/9p/v9fs.h
index 38762bf..019f4cc 100644
--- a/fs/9p/v9fs.h
+++ b/fs/9p/v9fs.h
@@ -51,6 +51,7 @@ enum p9_session_flags {
 enum p9_cache_modes {
 	CACHE_NONE,
 	CACHE_LOOSE,
+	CACHE_FSCACHE,
 };
 
 /**
@@ -60,6 +61,8 @@ enum p9_cache_modes {
  * @debug: debug level
  * @afid: authentication handle
  * @cache: cache mode of type &p9_cache_modes
+ * @cachetag: the tag of the cache associated with this session
+ * @fscache: session cookie associated with FS-Cache
  * @options: copy of options string given by user
  * @uname: string user name to mount hierarchy as
  * @aname: mount specifier for remote hierarchy
@@ -68,7 +71,7 @@ enum p9_cache_modes {
  * @dfltgid: default numeric groupid to mount hierarchy as
  * @uid: if %V9FS_ACCESS_SINGLE, the numeric uid which mounted the hierarchy
  * @clnt: reference to 9P network client instantiated for this session
- * @debugfs_dir: reference to debugfs_dir which can be used for add'l debug
+ * @slist: reference to list of registered 9p sessions
  *
  * This structure holds state for each session instance established during
  * a sys_mount() .
@@ -84,6 +87,10 @@ struct v9fs_session_info {
 	unsigned short debug;
 	unsigned int afid;
 	unsigned int cache;
+#ifdef CONFIG_9P_FSCACHE
+	char *cachetag;
+	struct fscache_cookie *fscache;
+#endif
 
 	char *uname;		/* user name to mount as */
 	char *aname;		/* name of remote hierarchy being mounted */
@@ -92,11 +99,9 @@ struct v9fs_session_info {
 	unsigned int dfltgid;	/* default gid for legacy support */
 	u32 uid;		/* if ACCESS_SINGLE, the uid that has access */
 	struct p9_client *clnt;	/* 9p client */
-	struct dentry *debugfs_dir;
+	struct list_head slist; /* list of sessions registered with v9fs */
 };
 
-extern struct dentry *v9fs_debugfs_root;
-
 struct p9_fid *v9fs_session_init(struct v9fs_session_info *, const char *,
 									char *);
 void v9fs_session_close(struct v9fs_session_info *v9ses);
diff --git a/fs/9p/v9fs_vfs.h b/fs/9p/v9fs_vfs.h
index f0c7de7..3a7560e 100644
--- a/fs/9p/v9fs_vfs.h
+++ b/fs/9p/v9fs_vfs.h
@@ -44,7 +44,13 @@ extern const struct file_operations v9fs_dir_operations;
 extern const struct dentry_operations v9fs_dentry_operations;
 extern const struct dentry_operations v9fs_cached_dentry_operations;
 
+#ifdef CONFIG_9P_FSCACHE
+struct inode *v9fs_alloc_inode(struct super_block *sb);
+void v9fs_destroy_inode(struct inode *inode);
+#endif
+
 struct inode *v9fs_get_inode(struct super_block *sb, int mode);
+void v9fs_clear_inode(struct inode *inode);
 ino_t v9fs_qid2ino(struct p9_qid *qid);
 void v9fs_stat2inode(struct p9_wstat *, struct inode *, struct super_block *);
 int v9fs_dir_release(struct inode *inode, struct file *filp);
diff --git a/fs/9p/vfs_addr.c b/fs/9p/vfs_addr.c
index 9282828..90e3844 100644
--- a/fs/9p/vfs_addr.c
+++ b/fs/9p/vfs_addr.c
@@ -38,6 +38,7 @@
 
 #include "v9fs.h"
 #include "v9fs_vfs.h"
+#include "cache.h"
 
 /**
  * v9fs_vfs_readpage - read an entire page in from 9P
@@ -52,18 +53,31 @@ static int v9fs_vfs_readpage(struct file *filp, struct page *page)
 	int retval;
 	loff_t offset;
 	char *buffer;
+	struct inode *inode;
 
+	inode = page->mapping->host;
 	P9_DPRINTK(P9_DEBUG_VFS, "\n");
+
+	BUG_ON(!PageLocked(page));
+
+	retval = v9fs_readpage_from_fscache(inode, page);
+	if (retval == 0)
+		return retval;
+
 	buffer = kmap(page);
 	offset = page_offset(page);
 
 	retval = v9fs_file_readn(filp, buffer, NULL, PAGE_CACHE_SIZE, offset);
-	if (retval < 0)
+	if (retval < 0) {
+		v9fs_uncache_page(inode, page);
 		goto done;
+	}
 
 	memset(buffer + retval, 0, PAGE_CACHE_SIZE - retval);
 	flush_dcache_page(page);
 	SetPageUptodate(page);
+
+	v9fs_readpage_to_fscache(inode, page);
 	retval = 0;
 
 done:
@@ -72,6 +86,78 @@ done:
 	return retval;
 }
 
+/**
+ * v9fs_vfs_readpages - read a set of pages from 9P
+ *
+ * @filp: file being read
+ * @mapping: the address space
+ * @pages: list of pages to read
+ * @nr_pages: count of pages to read
+ *
+ */
+
+static int v9fs_vfs_readpages(struct file *filp, struct address_space *mapping,
+			     struct list_head *pages, unsigned nr_pages)
+{
+	int ret = 0;
+	struct inode *inode;
+
+	inode = mapping->host;
+	P9_DPRINTK(P9_DEBUG_VFS, "inode: %p file: %p\n", inode, filp);
+
+	ret = v9fs_readpages_from_fscache(inode, mapping, pages, &nr_pages);
+	if (ret == 0)
+		return ret;
+
+	ret = read_cache_pages(mapping, pages, (void *)v9fs_vfs_readpage, filp);
+	P9_DPRINTK(P9_DEBUG_VFS, "  = %d\n", ret);
+	return ret;
+}
+
+/**
+ * v9fs_release_page - release the private state associated with a page
+ *
+ * Returns 1 if the page can be released, false otherwise.
+ */
+
+static int v9fs_release_page(struct page *page, gfp_t gfp)
+{
+	if (PagePrivate(page))
+		return 0;
+
+	return v9fs_fscache_release_page(page, gfp);
+}
+
+/**
+ * v9fs_invalidate_page - Invalidate a page completely or partially
+ *
+ * @page: structure to page
+ * @offset: offset in the page
+ */
+
+static void v9fs_invalidate_page(struct page *page, unsigned long offset)
+{
+	if (offset == 0)
+		v9fs_fscache_invalidate_page(page);
+}
+
+/**
+ * v9fs_launder_page - Writeback a dirty page
+ * Since the writes go directly to the server, we simply return a 0
+ * here to indicate success.
+ *
+ * Returns 0 on success.
+ */
+
+static int v9fs_launder_page(struct page *page)
+{
+	return 0;
+}
+
 const struct address_space_operations v9fs_addr_operations = {
       .readpage = v9fs_vfs_readpage,
+      .readpages = v9fs_vfs_readpages,
+      .releasepage = v9fs_release_page,
+      .invalidatepage = v9fs_invalidate_page,
+      .launder_page = v9fs_launder_page,
 };
diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c
index 68bf2af..3902bf4 100644
--- a/fs/9p/vfs_file.c
+++ b/fs/9p/vfs_file.c
@@ -32,6 +32,7 @@
 #include <linux/string.h>
 #include <linux/inet.h>
 #include <linux/list.h>
+#include <linux/pagemap.h>
 #include <asm/uaccess.h>
 #include <linux/idr.h>
 #include <net/9p/9p.h>
@@ -40,6 +41,7 @@
 #include "v9fs.h"
 #include "v9fs_vfs.h"
 #include "fid.h"
+#include "cache.h"
 
 static const struct file_operations v9fs_cached_file_operations;
 
@@ -72,7 +74,7 @@ int v9fs_file_open(struct inode *inode, struct file *file)
 			return err;
 		}
 		if (omode & P9_OTRUNC) {
-			inode->i_size = 0;
+			i_size_write(inode, 0);
 			inode->i_blocks = 0;
 		}
 		if ((file->f_flags & O_APPEND) && (!v9fs_extended(v9ses)))
@@ -85,6 +87,10 @@ int v9fs_file_open(struct inode *inode, struct file *file)
 		/* enable cached file options */
 		if(file->f_op == &v9fs_file_operations)
 			file->f_op = &v9fs_cached_file_operations;
+
+#ifdef CONFIG_9P_FSCACHE
+		v9fs_cache_inode_set_cookie(inode, file);
+#endif
 	}
 
 	return 0;
@@ -210,6 +216,7 @@ v9fs_file_write(struct file *filp, const char __user * data,
 	struct p9_client *clnt;
 	struct inode *inode = filp->f_path.dentry->d_inode;
 	int origin = *offset;
+	unsigned long pg_start, pg_end;
 
 	P9_DPRINTK(P9_DEBUG_VFS, "data %p count %d offset %x\n", data,
 		(int)count, (int)*offset);
@@ -225,7 +232,7 @@ v9fs_file_write(struct file *filp, const char __user * data,
 		if (count < rsize)
 			rsize = count;
 
-		n = p9_client_write(fid, NULL, data+total, *offset+total,
+		n = p9_client_write(fid, NULL, data+total, origin+total,
 									rsize);
 		if (n <= 0)
 			break;
@@ -234,14 +241,14 @@ v9fs_file_write(struct file *filp, const char __user * data,
 	} while (count > 0);
 
 	if (total > 0) {
-		invalidate_inode_pages2_range(inode->i_mapping, origin,
-								origin+total);
+		pg_start = origin >> PAGE_CACHE_SHIFT;
+		pg_end = (origin + total - 1) >> PAGE_CACHE_SHIFT;
+		if (inode->i_mapping && inode->i_mapping->nrpages)
+			invalidate_inode_pages2_range(inode->i_mapping,
+						      pg_start, pg_end);
 		*offset += total;
-	}
-
-	if (*offset > inode->i_size) {
-		inode->i_size = *offset;
-		inode->i_blocks = (inode->i_size + 512 - 1) >> 9;
+		i_size_write(inode, i_size_read(inode) + total);
+		inode->i_blocks = (i_size_read(inode) + 512 - 1) >> 9;
 	}
 
 	if (n < 0)
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index 06a223d..5947628 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -40,6 +40,7 @@
 #include "v9fs.h"
 #include "v9fs_vfs.h"
 #include "fid.h"
+#include "cache.h"
 
 static const struct inode_operations v9fs_dir_inode_operations;
 static const struct inode_operations v9fs_dir_inode_operations_ext;
@@ -197,6 +198,39 @@ v9fs_blank_wstat(struct p9_wstat *wstat)
 	wstat->extension = NULL;
 }
 
+#ifdef CONFIG_9P_FSCACHE
+/**
+ * v9fs_alloc_inode - helper function to allocate an inode
+ * This callback is executed before setting up the inode so that we
+ * can associate a vcookie with each inode.
+ *
+ */
+
+struct inode *v9fs_alloc_inode(struct super_block *sb)
+{
+	struct v9fs_cookie *vcookie;
+	vcookie = (struct v9fs_cookie *)kmem_cache_alloc(vcookie_cache,
+							 GFP_KERNEL);
+	if (!vcookie)
+		return NULL;
+
+	vcookie->fscache = NULL;
+	vcookie->qid = NULL;
+	spin_lock_init(&vcookie->lock);
+	return &vcookie->inode;
+}
+
+/**
+ * v9fs_destroy_inode - destroy an inode
+ *
+ */
+
+void v9fs_destroy_inode(struct inode *inode)
+{
+	kmem_cache_free(vcookie_cache, v9fs_inode2cookie(inode));
+}
+#endif
+
 /**
  * v9fs_get_inode - helper function to setup an inode
  * @sb: superblock
@@ -326,6 +360,21 @@ error:
 }
 */
 
+
+/**
+ * v9fs_clear_inode - release an inode
+ * @inode: inode to release
+ *
+ */
+void v9fs_clear_inode(struct inode *inode)
+{
+	filemap_fdatawrite(inode->i_mapping);
+
+#ifdef CONFIG_9P_FSCACHE
+	v9fs_cache_inode_put_cookie(inode);
+#endif
+}
+
 /**
  * v9fs_inode_from_fid - populate an inode by issuing a attribute request
  * @v9ses: session information
@@ -356,8 +405,14 @@ v9fs_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
 
 	v9fs_stat2inode(st, ret, sb);
 	ret->i_ino = v9fs_qid2ino(&st->qid);
+
+#ifdef CONFIG_9P_FSCACHE
+	v9fs_vcookie_set_qid(ret, &st->qid);
+	v9fs_cache_inode_get_cookie(ret);
+#endif
 	p9stat_free(st);
 	kfree(st);
+
 	return ret;
 
 error:
@@ -751,7 +806,7 @@ v9fs_vfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
 	P9_DPRINTK(P9_DEBUG_VFS, "dentry: %p\n", dentry);
 	err = -EPERM;
 	v9ses = v9fs_inode2v9ses(dentry->d_inode);
-	if (v9ses->cache == CACHE_LOOSE)
+	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
 		return simple_getattr(mnt, dentry, stat);
 
 	fid = v9fs_fid_lookup(dentry);
@@ -872,10 +927,10 @@ v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode,
 	} else
 		inode->i_rdev = 0;
 
-	inode->i_size = stat->length;
+	i_size_write(inode, stat->length);
 
 	/* not real number of blocks, but 512 byte ones ... */
-	inode->i_blocks = (inode->i_size + 512 - 1) >> 9;
+	inode->i_blocks = (i_size_read(inode) + 512 - 1) >> 9;
 }
 
 /**
diff --git a/fs/9p/vfs_super.c b/fs/9p/vfs_super.c
index 8961f1a..14a8644 100644
--- a/fs/9p/vfs_super.c
+++ b/fs/9p/vfs_super.c
@@ -44,21 +44,9 @@
 #include "v9fs_vfs.h"
 #include "fid.h"
 
-static void v9fs_clear_inode(struct inode *);
 static const struct super_operations v9fs_super_ops;
 
 /**
- * v9fs_clear_inode - release an inode
- * @inode: inode to release
- *
- */
-
-static void v9fs_clear_inode(struct inode *inode)
-{
-	filemap_fdatawrite(inode->i_mapping);
-}
-
-/**
  * v9fs_set_super - set the superblock
  * @s: super block
  * @data: file system specific data
@@ -220,6 +208,10 @@ v9fs_umount_begin(struct super_block *sb)
 }
 
 static const struct super_operations v9fs_super_ops = {
+#ifdef CONFIG_9P_FSCACHE
+	.alloc_inode = v9fs_alloc_inode,
+	.destroy_inode = v9fs_destroy_inode,
+#endif
 	.statfs = simple_statfs,
 	.clear_inode = v9fs_clear_inode,
 	.show_options = generic_show_options,
diff --git a/fs/adfs/inode.c b/fs/adfs/inode.c
index 798cb07..3f57ce4 100644
--- a/fs/adfs/inode.c
+++ b/fs/adfs/inode.c
@@ -19,9 +19,6 @@ static int
 adfs_get_block(struct inode *inode, sector_t block, struct buffer_head *bh,
 	       int create)
 {
-	if (block < 0)
-		goto abort_negative;
-
 	if (!create) {
 		if (block >= inode->i_blocks)
 			goto abort_toobig;
@@ -34,10 +31,6 @@ adfs_get_block(struct inode *inode, sector_t block, struct buffer_head *bh,
 	/* don't support allocation of blocks yet */
 	return -EIO;
 
-abort_negative:
-	adfs_error(inode->i_sb, "block %d < 0", block);
-	return -EIO;
-
 abort_toobig:
 	return 0;
 }
diff --git a/fs/afs/cache.h b/fs/afs/cache.h
deleted file mode 100644
index 5c4f6b4..0000000
--- a/fs/afs/cache.h
+++ /dev/null
@@ -1,12 +0,0 @@
-/* AFS local cache management interface
- *
- * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- */
-
-#include <linux/fscache.h>
diff --git a/fs/afs/internal.h b/fs/afs/internal.h
index 106be66..6ece2a1 100644
--- a/fs/afs/internal.h
+++ b/fs/afs/internal.h
@@ -18,10 +18,10 @@
 #include <linux/key.h>
 #include <linux/workqueue.h>
 #include <linux/sched.h>
+#include <linux/fscache.h>
 
 #include "afs.h"
 #include "afs_vl.h"
-#include "cache.h"
 
 #define AFS_CELL_MAX_ADDRS 15
 
diff --git a/fs/anon_inodes.c b/fs/anon_inodes.c
index d11c51f..2ca7a7c 100644
--- a/fs/anon_inodes.c
+++ b/fs/anon_inodes.c
@@ -8,8 +8,10 @@
  *
  */
 
+#include <linux/cred.h>
 #include <linux/file.h>
 #include <linux/poll.h>
+#include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/init.h>
 #include <linux/fs.h>
diff --git a/fs/attr.c b/fs/attr.c
index 9fe1b1b..96d394b 100644
--- a/fs/attr.c
+++ b/fs/attr.c
@@ -18,7 +18,7 @@
 /* Taken over from the old code... */
 
 /* POSIX UID/GID verification for setting inode attributes. */
-int inode_change_ok(struct inode *inode, struct iattr *attr)
+int inode_change_ok(const struct inode *inode, struct iattr *attr)
 {
 	int retval = -EPERM;
 	unsigned int ia_valid = attr->ia_valid;
@@ -60,9 +60,51 @@ fine:
 error:
 	return retval;
 }
-
 EXPORT_SYMBOL(inode_change_ok);
 
+/**
+ * inode_newsize_ok - may this inode be truncated to a given size
+ * @inode:	the inode to be truncated
+ * @offset:	the new size to assign to the inode
+ * @Returns:	0 on success, -ve errno on failure
+ *
+ * inode_newsize_ok will check filesystem limits and ulimits to check that the
+ * new inode size is within limits. inode_newsize_ok will also send SIGXFSZ
+ * when necessary. Caller must not proceed with inode size change if failure is
+ * returned. @inode must be a file (not directory), with appropriate
+ * permissions to allow truncate (inode_newsize_ok does NOT check these
+ * conditions).
+ *
+ * inode_newsize_ok must be called with i_mutex held.
+ */
+int inode_newsize_ok(const struct inode *inode, loff_t offset)
+{
+	if (inode->i_size < offset) {
+		unsigned long limit;
+
+		limit = current->signal->rlim[RLIMIT_FSIZE].rlim_cur;
+		if (limit != RLIM_INFINITY && offset > limit)
+			goto out_sig;
+		if (offset > inode->i_sb->s_maxbytes)
+			goto out_big;
+	} else {
+		/*
+		 * truncation of in-use swapfiles is disallowed - it would
+		 * cause subsequent swapout to scribble on the now-freed
+		 * blocks.
+		 */
+		if (IS_SWAPFILE(inode))
+			return -ETXTBSY;
+	}
+
+	return 0;
+out_sig:
+	send_sig(SIGXFSZ, current, 0);
+out_big:
+	return -EFBIG;
+}
+EXPORT_SYMBOL(inode_newsize_ok);
+
 int inode_setattr(struct inode * inode, struct iattr * attr)
 {
 	unsigned int ia_valid = attr->ia_valid;
diff --git a/fs/befs/linuxvfs.c b/fs/befs/linuxvfs.c
index dd376c1..33baf27 100644
--- a/fs/befs/linuxvfs.c
+++ b/fs/befs/linuxvfs.c
@@ -737,12 +737,7 @@ befs_put_super(struct super_block *sb)
 {
 	kfree(BEFS_SB(sb)->mount_opts.iocharset);
 	BEFS_SB(sb)->mount_opts.iocharset = NULL;
-
-	if (BEFS_SB(sb)->nls) {
-		unload_nls(BEFS_SB(sb)->nls);
-		BEFS_SB(sb)->nls = NULL;
-	}
-
+	unload_nls(BEFS_SB(sb)->nls);
 	kfree(sb->s_fs_info);
 	sb->s_fs_info = NULL;
 }
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index 442d94f..b9b3bb5 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -1711,42 +1711,52 @@ struct elf_note_info {
 	int numnote;
 };
 
-static int fill_note_info(struct elfhdr *elf, int phdrs,
-			  struct elf_note_info *info,
-			  long signr, struct pt_regs *regs)
+static int elf_note_info_init(struct elf_note_info *info)
 {
-#define	NUM_NOTES	6
-	struct list_head *t;
-
-	info->notes = NULL;
-	info->prstatus = NULL;
-	info->psinfo = NULL;
-	info->fpu = NULL;
-#ifdef ELF_CORE_COPY_XFPREGS
-	info->xfpu = NULL;
-#endif
+	memset(info, 0, sizeof(*info));
 	INIT_LIST_HEAD(&info->thread_list);
 
-	info->notes = kmalloc(NUM_NOTES * sizeof(struct memelfnote),
-			      GFP_KERNEL);
+	/* Allocate space for six ELF notes */
+	info->notes = kmalloc(6 * sizeof(struct memelfnote), GFP_KERNEL);
 	if (!info->notes)
 		return 0;
 	info->psinfo = kmalloc(sizeof(*info->psinfo), GFP_KERNEL);
 	if (!info->psinfo)
-		return 0;
+		goto notes_free;
 	info->prstatus = kmalloc(sizeof(*info->prstatus), GFP_KERNEL);
 	if (!info->prstatus)
-		return 0;
+		goto psinfo_free;
 	info->fpu = kmalloc(sizeof(*info->fpu), GFP_KERNEL);
 	if (!info->fpu)
-		return 0;
+		goto prstatus_free;
 #ifdef ELF_CORE_COPY_XFPREGS
 	info->xfpu = kmalloc(sizeof(*info->xfpu), GFP_KERNEL);
 	if (!info->xfpu)
-		return 0;
+		goto fpu_free;
+#endif
+	return 1;
+#ifdef ELF_CORE_COPY_XFPREGS
+ fpu_free:
+	kfree(info->fpu);
 #endif
+ prstatus_free:
+	kfree(info->prstatus);
+ psinfo_free:
+	kfree(info->psinfo);
+ notes_free:
+	kfree(info->notes);
+	return 0;
+}
+
+static int fill_note_info(struct elfhdr *elf, int phdrs,
+			  struct elf_note_info *info,
+			  long signr, struct pt_regs *regs)
+{
+	struct list_head *t;
+
+	if (!elf_note_info_init(info))
+		return 0;
 
-	info->thread_status_size = 0;
 	if (signr) {
 		struct core_thread *ct;
 		struct elf_thread_status *ets;
@@ -1806,8 +1816,6 @@ static int fill_note_info(struct elfhdr *elf, int phdrs,
 #endif
 
 	return 1;
-
-#undef NUM_NOTES
 }
 
 static size_t get_note_info_size(struct elf_note_info *info)
diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index 7628547..38502c6 100644
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c
@@ -283,20 +283,23 @@ static int load_elf_fdpic_binary(struct linux_binprm *bprm,
 	}
 
 	stack_size = exec_params.stack_size;
-	if (stack_size < interp_params.stack_size)
-		stack_size = interp_params.stack_size;
-
 	if (exec_params.flags & ELF_FDPIC_FLAG_EXEC_STACK)
 		executable_stack = EXSTACK_ENABLE_X;
 	else if (exec_params.flags & ELF_FDPIC_FLAG_NOEXEC_STACK)
 		executable_stack = EXSTACK_DISABLE_X;
-	else if (interp_params.flags & ELF_FDPIC_FLAG_EXEC_STACK)
-		executable_stack = EXSTACK_ENABLE_X;
-	else if (interp_params.flags & ELF_FDPIC_FLAG_NOEXEC_STACK)
-		executable_stack = EXSTACK_DISABLE_X;
 	else
 		executable_stack = EXSTACK_DEFAULT;
 
+	if (stack_size == 0) {
+		stack_size = interp_params.stack_size;
+		if (interp_params.flags & ELF_FDPIC_FLAG_EXEC_STACK)
+			executable_stack = EXSTACK_ENABLE_X;
+		else if (interp_params.flags & ELF_FDPIC_FLAG_NOEXEC_STACK)
+			executable_stack = EXSTACK_DISABLE_X;
+		else
+			executable_stack = EXSTACK_DEFAULT;
+	}
+
 	retval = -ENOEXEC;
 	if (stack_size == 0)
 		goto error;
diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c
index e92f229..a279665 100644
--- a/fs/binfmt_flat.c
+++ b/fs/binfmt_flat.c
@@ -278,8 +278,6 @@ static int decompress_exec(
 		ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
 		if (ret <= 0)
 			break;
-		if (ret >= (unsigned long) -4096)
-			break;
 		len -= ret;
 
 		strm.next_in = buf;
@@ -335,7 +333,7 @@ calc_reloc(unsigned long r, struct lib_info *p, int curid, int internalp)
 					"(%d != %d)", (unsigned) r, curid, id);
 			goto failed;
 		} else if ( ! p->lib_list[id].loaded &&
-				load_flat_shared_library(id, p) > (unsigned long) -4096) {
+				IS_ERR_VALUE(load_flat_shared_library(id, p))) {
 			printk("BINFMT_FLAT: failed to load library %d", id);
 			goto failed;
 		}
@@ -545,7 +543,7 @@ static int load_flat_file(struct linux_binprm * bprm,
 		textpos = do_mmap(bprm->file, 0, text_len, PROT_READ|PROT_EXEC,
 				  MAP_PRIVATE|MAP_EXECUTABLE, 0);
 		up_write(&current->mm->mmap_sem);
-		if (!textpos  || textpos >= (unsigned long) -4096) {
+		if (!textpos || IS_ERR_VALUE(textpos)) {
 			if (!textpos)
 				textpos = (unsigned long) -ENOMEM;
 			printk("Unable to mmap process text, errno %d\n", (int)-textpos);
@@ -560,7 +558,7 @@ static int load_flat_file(struct linux_binprm * bprm,
 			PROT_READ|PROT_WRITE|PROT_EXEC, MAP_PRIVATE, 0);
 		up_write(&current->mm->mmap_sem);
 
-		if (realdatastart == 0 || realdatastart >= (unsigned long)-4096) {
+		if (realdatastart == 0 || IS_ERR_VALUE(realdatastart)) {
 			if (!realdatastart)
 				realdatastart = (unsigned long) -ENOMEM;
 			printk("Unable to allocate RAM for process data, errno %d\n",
@@ -587,7 +585,7 @@ static int load_flat_file(struct linux_binprm * bprm,
 			result = bprm->file->f_op->read(bprm->file, (char *) datapos,
 					data_len + (relocs * sizeof(unsigned long)), &fpos);
 		}
-		if (result >= (unsigned long)-4096) {
+		if (IS_ERR_VALUE(result)) {
 			printk("Unable to read data+bss, errno %d\n", (int)-result);
 			do_munmap(current->mm, textpos, text_len);
 			do_munmap(current->mm, realdatastart, data_len + extra);
@@ -607,7 +605,7 @@ static int load_flat_file(struct linux_binprm * bprm,
 			PROT_READ | PROT_EXEC | PROT_WRITE, MAP_PRIVATE, 0);
 		up_write(&current->mm->mmap_sem);
 
-		if (!textpos  || textpos >= (unsigned long) -4096) {
+		if (!textpos || IS_ERR_VALUE(textpos)) {
 			if (!textpos)
 				textpos = (unsigned long) -ENOMEM;
 			printk("Unable to allocate RAM for process text/data, errno %d\n",
@@ -641,7 +639,7 @@ static int load_flat_file(struct linux_binprm * bprm,
 			fpos = 0;
 			result = bprm->file->f_op->read(bprm->file,
 					(char *) textpos, text_len, &fpos);
-			if (result < (unsigned long) -4096)
+			if (!IS_ERR_VALUE(result))
 				result = decompress_exec(bprm, text_len, (char *) datapos,
 						 data_len + (relocs * sizeof(unsigned long)), 0);
 		}
@@ -651,13 +649,13 @@ static int load_flat_file(struct linux_binprm * bprm,
 			fpos = 0;
 			result = bprm->file->f_op->read(bprm->file,
 					(char *) textpos, text_len, &fpos);
-			if (result < (unsigned long) -4096) {
+			if (!IS_ERR_VALUE(result)) {
 				fpos = ntohl(hdr->data_start);
 				result = bprm->file->f_op->read(bprm->file, (char *) datapos,
 					data_len + (relocs * sizeof(unsigned long)), &fpos);
 			}
 		}
-		if (result >= (unsigned long)-4096) {
+		if (IS_ERR_VALUE(result)) {
 			printk("Unable to read code+data+bss, errno %d\n",(int)-result);
 			do_munmap(current->mm, textpos, text_len + data_len + extra +
 				MAX_SHARED_LIBS * sizeof(unsigned long));
@@ -835,7 +833,7 @@ static int load_flat_shared_library(int id, struct lib_info *libs)
 
 	res = prepare_binprm(&bprm);
 
-	if (res <= (unsigned long)-4096)
+	if (!IS_ERR_VALUE(res))
 		res = load_flat_file(&bprm, libs, id, NULL);
 
 	abort_creds(bprm.cred);
@@ -880,7 +878,7 @@ static int load_flat_binary(struct linux_binprm * bprm, struct pt_regs * regs)
 	stack_len += FLAT_DATA_ALIGN - 1;  /* reserve for upcoming alignment */
 	
 	res = load_flat_file(bprm, &libinfo, 0, &stack_len);
-	if (res > (unsigned long)-4096)
+	if (IS_ERR_VALUE(res))
 		return res;
 	
 	/* Update data segment pointers for all libraries */
diff --git a/fs/bio.c b/fs/bio.c
index 7673800..402cb84 100644
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -249,6 +249,7 @@ void bio_free(struct bio *bio, struct bio_set *bs)
 
 	mempool_free(p, bs->bio_pool);
 }
+EXPORT_SYMBOL(bio_free);
 
 void bio_init(struct bio *bio)
 {
@@ -257,6 +258,7 @@ void bio_init(struct bio *bio)
 	bio->bi_comp_cpu = -1;
 	atomic_set(&bio->bi_cnt, 1);
 }
+EXPORT_SYMBOL(bio_init);
 
 /**
  * bio_alloc_bioset - allocate a bio for I/O
@@ -311,6 +313,7 @@ err_free:
 	mempool_free(p, bs->bio_pool);
 	return NULL;
 }
+EXPORT_SYMBOL(bio_alloc_bioset);
 
 static void bio_fs_destructor(struct bio *bio)
 {
@@ -337,6 +340,7 @@ struct bio *bio_alloc(gfp_t gfp_mask, int nr_iovecs)
 
 	return bio;
 }
+EXPORT_SYMBOL(bio_alloc);
 
 static void bio_kmalloc_destructor(struct bio *bio)
 {
@@ -380,6 +384,7 @@ struct bio *bio_kmalloc(gfp_t gfp_mask, int nr_iovecs)
 
 	return bio;
 }
+EXPORT_SYMBOL(bio_kmalloc);
 
 void zero_fill_bio(struct bio *bio)
 {
@@ -416,6 +421,7 @@ void bio_put(struct bio *bio)
 		bio->bi_destructor(bio);
 	}
 }
+EXPORT_SYMBOL(bio_put);
 
 inline int bio_phys_segments(struct request_queue *q, struct bio *bio)
 {
@@ -424,6 +430,7 @@ inline int bio_phys_segments(struct request_queue *q, struct bio *bio)
 
 	return bio->bi_phys_segments;
 }
+EXPORT_SYMBOL(bio_phys_segments);
 
 /**
  * 	__bio_clone	-	clone a bio
@@ -451,6 +458,7 @@ void __bio_clone(struct bio *bio, struct bio *bio_src)
 	bio->bi_size = bio_src->bi_size;
 	bio->bi_idx = bio_src->bi_idx;
 }
+EXPORT_SYMBOL(__bio_clone);
 
 /**
  *	bio_clone	-	clone a bio
@@ -482,6 +490,7 @@ struct bio *bio_clone(struct bio *bio, gfp_t gfp_mask)
 
 	return b;
 }
+EXPORT_SYMBOL(bio_clone);
 
 /**
  *	bio_get_nr_vecs		- return approx number of vecs
@@ -505,6 +514,7 @@ int bio_get_nr_vecs(struct block_device *bdev)
 
 	return nr_pages;
 }
+EXPORT_SYMBOL(bio_get_nr_vecs);
 
 static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page
 			  *page, unsigned int len, unsigned int offset,
@@ -635,6 +645,7 @@ int bio_add_pc_page(struct request_queue *q, struct bio *bio, struct page *page,
 	return __bio_add_page(q, bio, page, len, offset,
 			      queue_max_hw_sectors(q));
 }
+EXPORT_SYMBOL(bio_add_pc_page);
 
 /**
  *	bio_add_page	-	attempt to add page to bio
@@ -655,6 +666,7 @@ int bio_add_page(struct bio *bio, struct page *page, unsigned int len,
 	struct request_queue *q = bdev_get_queue(bio->bi_bdev);
 	return __bio_add_page(q, bio, page, len, offset, queue_max_sectors(q));
 }
+EXPORT_SYMBOL(bio_add_page);
 
 struct bio_map_data {
 	struct bio_vec *iovecs;
@@ -776,6 +788,7 @@ int bio_uncopy_user(struct bio *bio)
 	bio_put(bio);
 	return ret;
 }
+EXPORT_SYMBOL(bio_uncopy_user);
 
 /**
  *	bio_copy_user_iov	-	copy user data to bio
@@ -920,6 +933,7 @@ struct bio *bio_copy_user(struct request_queue *q, struct rq_map_data *map_data,
 
 	return bio_copy_user_iov(q, map_data, &iov, 1, write_to_vm, gfp_mask);
 }
+EXPORT_SYMBOL(bio_copy_user);
 
 static struct bio *__bio_map_user_iov(struct request_queue *q,
 				      struct block_device *bdev,
@@ -1050,6 +1064,7 @@ struct bio *bio_map_user(struct request_queue *q, struct block_device *bdev,
 
 	return bio_map_user_iov(q, bdev, &iov, 1, write_to_vm, gfp_mask);
 }
+EXPORT_SYMBOL(bio_map_user);
 
 /**
  *	bio_map_user_iov - map user sg_iovec table into bio
@@ -1117,13 +1132,13 @@ void bio_unmap_user(struct bio *bio)
 	__bio_unmap_user(bio);
 	bio_put(bio);
 }
+EXPORT_SYMBOL(bio_unmap_user);
 
 static void bio_map_kern_endio(struct bio *bio, int err)
 {
 	bio_put(bio);
 }
 
-
 static struct bio *__bio_map_kern(struct request_queue *q, void *data,
 				  unsigned int len, gfp_t gfp_mask)
 {
@@ -1189,6 +1204,7 @@ struct bio *bio_map_kern(struct request_queue *q, void *data, unsigned int len,
 	bio_put(bio);
 	return ERR_PTR(-EINVAL);
 }
+EXPORT_SYMBOL(bio_map_kern);
 
 static void bio_copy_kern_endio(struct bio *bio, int err)
 {
@@ -1250,6 +1266,7 @@ struct bio *bio_copy_kern(struct request_queue *q, void *data, unsigned int len,
 
 	return bio;
 }
+EXPORT_SYMBOL(bio_copy_kern);
 
 /*
  * bio_set_pages_dirty() and bio_check_pages_dirty() are support functions
@@ -1400,6 +1417,7 @@ void bio_endio(struct bio *bio, int error)
 	if (bio->bi_end_io)
 		bio->bi_end_io(bio, error);
 }
+EXPORT_SYMBOL(bio_endio);
 
 void bio_pair_release(struct bio_pair *bp)
 {
@@ -1410,6 +1428,7 @@ void bio_pair_release(struct bio_pair *bp)
 		mempool_free(bp, bp->bio2.bi_private);
 	}
 }
+EXPORT_SYMBOL(bio_pair_release);
 
 static void bio_pair_end_1(struct bio *bi, int err)
 {
@@ -1477,6 +1496,7 @@ struct bio_pair *bio_split(struct bio *bi, int first_sectors)
 
 	return bp;
 }
+EXPORT_SYMBOL(bio_split);
 
 /**
  *      bio_sector_offset - Find hardware sector offset in bio
@@ -1547,6 +1567,7 @@ void bioset_free(struct bio_set *bs)
 
 	kfree(bs);
 }
+EXPORT_SYMBOL(bioset_free);
 
 /**
  * bioset_create  - Create a bio_set
@@ -1592,6 +1613,7 @@ bad:
 	bioset_free(bs);
 	return NULL;
 }
+EXPORT_SYMBOL(bioset_create);
 
 static void __init biovec_init_slabs(void)
 {
@@ -1636,29 +1658,4 @@ static int __init init_bio(void)
 
 	return 0;
 }
-
 subsys_initcall(init_bio);
-
-EXPORT_SYMBOL(bio_alloc);
-EXPORT_SYMBOL(bio_kmalloc);
-EXPORT_SYMBOL(bio_put);
-EXPORT_SYMBOL(bio_free);
-EXPORT_SYMBOL(bio_endio);
-EXPORT_SYMBOL(bio_init);
-EXPORT_SYMBOL(__bio_clone);
-EXPORT_SYMBOL(bio_clone);
-EXPORT_SYMBOL(bio_phys_segments);
-EXPORT_SYMBOL(bio_add_page);
-EXPORT_SYMBOL(bio_add_pc_page);
-EXPORT_SYMBOL(bio_get_nr_vecs);
-EXPORT_SYMBOL(bio_map_user);
-EXPORT_SYMBOL(bio_unmap_user);
-EXPORT_SYMBOL(bio_map_kern);
-EXPORT_SYMBOL(bio_copy_kern);
-EXPORT_SYMBOL(bio_pair_release);
-EXPORT_SYMBOL(bio_split);
-EXPORT_SYMBOL(bio_copy_user);
-EXPORT_SYMBOL(bio_uncopy_user);
-EXPORT_SYMBOL(bioset_create);
-EXPORT_SYMBOL(bioset_free);
-EXPORT_SYMBOL(bio_alloc_bioset);
diff --git a/fs/block_dev.c b/fs/block_dev.c
index 5d1ed50..9cf4b92 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -216,8 +216,6 @@ EXPORT_SYMBOL(fsync_bdev);
  * freeze_bdev  --  lock a filesystem and force it into a consistent state
  * @bdev:	blockdevice to lock
  *
- * This takes the block device bd_mount_sem to make sure no new mounts
- * happen on bdev until thaw_bdev() is called.
  * If a superblock is found on this device, we take the s_umount semaphore
  * on it to make sure nobody unmounts until the snapshot creation is done.
  * The reference counter (bd_fsfreeze_count) guarantees that only the last
@@ -232,46 +230,55 @@ struct super_block *freeze_bdev(struct block_device *bdev)
 	int error = 0;
 
 	mutex_lock(&bdev->bd_fsfreeze_mutex);
-	if (bdev->bd_fsfreeze_count > 0) {
-		bdev->bd_fsfreeze_count++;
+	if (++bdev->bd_fsfreeze_count > 1) {
+		/*
+		 * We don't even need to grab a reference - the first call
+		 * to freeze_bdev grab an active reference and only the last
+		 * thaw_bdev drops it.
+		 */
 		sb = get_super(bdev);
+		drop_super(sb);
 		mutex_unlock(&bdev->bd_fsfreeze_mutex);
 		return sb;
 	}
-	bdev->bd_fsfreeze_count++;
-
-	down(&bdev->bd_mount_sem);
-	sb = get_super(bdev);
-	if (sb && !(sb->s_flags & MS_RDONLY)) {
-		sb->s_frozen = SB_FREEZE_WRITE;
-		smp_wmb();
-
-		sync_filesystem(sb);
-
-		sb->s_frozen = SB_FREEZE_TRANS;
-		smp_wmb();
-
-		sync_blockdev(sb->s_bdev);
-
-		if (sb->s_op->freeze_fs) {
-			error = sb->s_op->freeze_fs(sb);
-			if (error) {
-				printk(KERN_ERR
-					"VFS:Filesystem freeze failed\n");
-				sb->s_frozen = SB_UNFROZEN;
-				drop_super(sb);
-				up(&bdev->bd_mount_sem);
-				bdev->bd_fsfreeze_count--;
-				mutex_unlock(&bdev->bd_fsfreeze_mutex);
-				return ERR_PTR(error);
-			}
+
+	sb = get_active_super(bdev);
+	if (!sb)
+		goto out;
+	if (sb->s_flags & MS_RDONLY) {
+		deactivate_locked_super(sb);
+		mutex_unlock(&bdev->bd_fsfreeze_mutex);
+		return sb;
+	}
+
+	sb->s_frozen = SB_FREEZE_WRITE;
+	smp_wmb();
+
+	sync_filesystem(sb);
+
+	sb->s_frozen = SB_FREEZE_TRANS;
+	smp_wmb();
+
+	sync_blockdev(sb->s_bdev);
+
+	if (sb->s_op->freeze_fs) {
+		error = sb->s_op->freeze_fs(sb);
+		if (error) {
+			printk(KERN_ERR
+				"VFS:Filesystem freeze failed\n");
+			sb->s_frozen = SB_UNFROZEN;
+			deactivate_locked_super(sb);
+			bdev->bd_fsfreeze_count--;
+			mutex_unlock(&bdev->bd_fsfreeze_mutex);
+			return ERR_PTR(error);
 		}
 	}
+	up_write(&sb->s_umount);
 
+ out:
 	sync_blockdev(bdev);
 	mutex_unlock(&bdev->bd_fsfreeze_mutex);
-
-	return sb;	/* thaw_bdev releases s->s_umount and bd_mount_sem */
+	return sb;	/* thaw_bdev releases s->s_umount */
 }
 EXPORT_SYMBOL(freeze_bdev);
 
@@ -284,44 +291,44 @@ EXPORT_SYMBOL(freeze_bdev);
  */
 int thaw_bdev(struct block_device *bdev, struct super_block *sb)
 {
-	int error = 0;
+	int error = -EINVAL;
 
 	mutex_lock(&bdev->bd_fsfreeze_mutex);
-	if (!bdev->bd_fsfreeze_count) {
-		mutex_unlock(&bdev->bd_fsfreeze_mutex);
-		return -EINVAL;
-	}
-
-	bdev->bd_fsfreeze_count--;
-	if (bdev->bd_fsfreeze_count > 0) {
-		if (sb)
-			drop_super(sb);
-		mutex_unlock(&bdev->bd_fsfreeze_mutex);
-		return 0;
-	}
-
-	if (sb) {
-		BUG_ON(sb->s_bdev != bdev);
-		if (!(sb->s_flags & MS_RDONLY)) {
-			if (sb->s_op->unfreeze_fs) {
-				error = sb->s_op->unfreeze_fs(sb);
-				if (error) {
-					printk(KERN_ERR
-						"VFS:Filesystem thaw failed\n");
-					sb->s_frozen = SB_FREEZE_TRANS;
-					bdev->bd_fsfreeze_count++;
-					mutex_unlock(&bdev->bd_fsfreeze_mutex);
-					return error;
-				}
-			}
-			sb->s_frozen = SB_UNFROZEN;
-			smp_wmb();
-			wake_up(&sb->s_wait_unfrozen);
+	if (!bdev->bd_fsfreeze_count)
+		goto out_unlock;
+
+	error = 0;
+	if (--bdev->bd_fsfreeze_count > 0)
+		goto out_unlock;
+
+	if (!sb)
+		goto out_unlock;
+
+	BUG_ON(sb->s_bdev != bdev);
+	down_write(&sb->s_umount);
+	if (sb->s_flags & MS_RDONLY)
+		goto out_deactivate;
+
+	if (sb->s_op->unfreeze_fs) {
+		error = sb->s_op->unfreeze_fs(sb);
+		if (error) {
+			printk(KERN_ERR
+				"VFS:Filesystem thaw failed\n");
+			sb->s_frozen = SB_FREEZE_TRANS;
+			bdev->bd_fsfreeze_count++;
+			mutex_unlock(&bdev->bd_fsfreeze_mutex);
+			return error;
 		}
-		drop_super(sb);
 	}
 
-	up(&bdev->bd_mount_sem);
+	sb->s_frozen = SB_UNFROZEN;
+	smp_wmb();
+	wake_up(&sb->s_wait_unfrozen);
+
+out_deactivate:
+	if (sb)
+		deactivate_locked_super(sb);
+out_unlock:
 	mutex_unlock(&bdev->bd_fsfreeze_mutex);
 	return 0;
 }
@@ -430,7 +437,6 @@ static void init_once(void *foo)
 
 	memset(bdev, 0, sizeof(*bdev));
 	mutex_init(&bdev->bd_mutex);
-	sema_init(&bdev->bd_mount_sem, 1);
 	INIT_LIST_HEAD(&bdev->bd_inodes);
 	INIT_LIST_HEAD(&bdev->bd_list);
 #ifdef CONFIG_SYSFS
diff --git a/fs/btrfs/acl.c b/fs/btrfs/acl.c
index f128427..3616042 100644
--- a/fs/btrfs/acl.c
+++ b/fs/btrfs/acl.c
@@ -27,7 +27,7 @@
 #include "btrfs_inode.h"
 #include "xattr.h"
 
-#ifdef CONFIG_FS_POSIX_ACL
+#ifdef CONFIG_BTRFS_FS_POSIX_ACL
 
 static struct posix_acl *btrfs_get_acl(struct inode *inode, int type)
 {
@@ -313,7 +313,7 @@ struct xattr_handler btrfs_xattr_acl_access_handler = {
 	.set	= btrfs_xattr_acl_access_set,
 };
 
-#else /* CONFIG_FS_POSIX_ACL */
+#else /* CONFIG_BTRFS_FS_POSIX_ACL */
 
 int btrfs_acl_chmod(struct inode *inode)
 {
@@ -325,4 +325,4 @@ int btrfs_init_acl(struct inode *inode, struct inode *dir)
 	return 0;
 }
 
-#endif /* CONFIG_FS_POSIX_ACL */
+#endif /* CONFIG_BTRFS_FS_POSIX_ACL */
diff --git a/fs/btrfs/async-thread.c b/fs/btrfs/async-thread.c
index 019e8af..c0861e7 100644
--- a/fs/btrfs/async-thread.c
+++ b/fs/btrfs/async-thread.c
@@ -48,6 +48,9 @@ struct btrfs_worker_thread {
 	/* number of things on the pending list */
 	atomic_t num_pending;
 
+	/* reference counter for this struct */
+	atomic_t refs;
+
 	unsigned long sequence;
 
 	/* protects the pending list. */
@@ -61,6 +64,51 @@ struct btrfs_worker_thread {
 };
 
 /*
+ * btrfs_start_workers uses kthread_run, which can block waiting for memory
+ * for a very long time.  It will actually throttle on page writeback,
+ * and so it may not make progress until after our btrfs worker threads
+ * process all of the pending work structs in their queue
+ *
+ * This means we can't use btrfs_start_workers from inside a btrfs worker
+ * thread that is used as part of cleaning dirty memory, which pretty much
+ * involves all of the worker threads.
+ *
+ * Instead we have a helper queue who never has more than one thread
+ * where we scheduler thread start operations.  This worker_start struct
+ * is used to contain the work and hold a pointer to the queue that needs
+ * another worker.
+ */
+struct worker_start {
+	struct btrfs_work work;
+	struct btrfs_workers *queue;
+};
+
+static void start_new_worker_func(struct btrfs_work *work)
+{
+	struct worker_start *start;
+	start = container_of(work, struct worker_start, work);
+	btrfs_start_workers(start->queue, 1);
+	kfree(start);
+}
+
+static int start_new_worker(struct btrfs_workers *queue)
+{
+	struct worker_start *start;
+	int ret;
+
+	start = kzalloc(sizeof(*start), GFP_NOFS);
+	if (!start)
+		return -ENOMEM;
+
+	start->work.func = start_new_worker_func;
+	start->queue = queue;
+	ret = btrfs_queue_worker(queue->atomic_worker_start, &start->work);
+	if (ret)
+		kfree(start);
+	return ret;
+}
+
+/*
  * helper function to move a thread onto the idle list after it
  * has finished some requests.
  */
@@ -71,7 +119,12 @@ static void check_idle_worker(struct btrfs_worker_thread *worker)
 		unsigned long flags;
 		spin_lock_irqsave(&worker->workers->lock, flags);
 		worker->idle = 1;
-		list_move(&worker->worker_list, &worker->workers->idle_list);
+
+		/* the list may be empty if the worker is just starting */
+		if (!list_empty(&worker->worker_list)) {
+			list_move(&worker->worker_list,
+				 &worker->workers->idle_list);
+		}
 		spin_unlock_irqrestore(&worker->workers->lock, flags);
 	}
 }
@@ -87,23 +140,51 @@ static void check_busy_worker(struct btrfs_worker_thread *worker)
 		unsigned long flags;
 		spin_lock_irqsave(&worker->workers->lock, flags);
 		worker->idle = 0;
-		list_move_tail(&worker->worker_list,
-			       &worker->workers->worker_list);
+
+		if (!list_empty(&worker->worker_list)) {
+			list_move_tail(&worker->worker_list,
+				      &worker->workers->worker_list);
+		}
 		spin_unlock_irqrestore(&worker->workers->lock, flags);
 	}
 }
 
-static noinline int run_ordered_completions(struct btrfs_workers *workers,
-					    struct btrfs_work *work)
+static void check_pending_worker_creates(struct btrfs_worker_thread *worker)
 {
+	struct btrfs_workers *workers = worker->workers;
 	unsigned long flags;
 
+	rmb();
+	if (!workers->atomic_start_pending)
+		return;
+
+	spin_lock_irqsave(&workers->lock, flags);
+	if (!workers->atomic_start_pending)
+		goto out;
+
+	workers->atomic_start_pending = 0;
+	if (workers->num_workers + workers->num_workers_starting >=
+	    workers->max_workers)
+		goto out;
+
+	workers->num_workers_starting += 1;
+	spin_unlock_irqrestore(&workers->lock, flags);
+	start_new_worker(workers);
+	return;
+
+out:
+	spin_unlock_irqrestore(&workers->lock, flags);
+}
+
+static noinline int run_ordered_completions(struct btrfs_workers *workers,
+					    struct btrfs_work *work)
+{
 	if (!workers->ordered)
 		return 0;
 
 	set_bit(WORK_DONE_BIT, &work->flags);
 
-	spin_lock_irqsave(&workers->lock, flags);
+	spin_lock(&workers->order_lock);
 
 	while (1) {
 		if (!list_empty(&workers->prio_order_list)) {
@@ -126,45 +207,118 @@ static noinline int run_ordered_completions(struct btrfs_workers *workers,
 		if (test_and_set_bit(WORK_ORDER_DONE_BIT, &work->flags))
 			break;
 
-		spin_unlock_irqrestore(&workers->lock, flags);
+		spin_unlock(&workers->order_lock);
 
 		work->ordered_func(work);
 
 		/* now take the lock again and call the freeing code */
-		spin_lock_irqsave(&workers->lock, flags);
+		spin_lock(&workers->order_lock);
 		list_del(&work->order_list);
 		work->ordered_free(work);
 	}
 
-	spin_unlock_irqrestore(&workers->lock, flags);
+	spin_unlock(&workers->order_lock);
 	return 0;
 }
 
+static void put_worker(struct btrfs_worker_thread *worker)
+{
+	if (atomic_dec_and_test(&worker->refs))
+		kfree(worker);
+}
+
+static int try_worker_shutdown(struct btrfs_worker_thread *worker)
+{
+	int freeit = 0;
+
+	spin_lock_irq(&worker->lock);
+	spin_lock(&worker->workers->lock);
+	if (worker->workers->num_workers > 1 &&
+	    worker->idle &&
+	    !worker->working &&
+	    !list_empty(&worker->worker_list) &&
+	    list_empty(&worker->prio_pending) &&
+	    list_empty(&worker->pending) &&
+	    atomic_read(&worker->num_pending) == 0) {
+		freeit = 1;
+		list_del_init(&worker->worker_list);
+		worker->workers->num_workers--;
+	}
+	spin_unlock(&worker->workers->lock);
+	spin_unlock_irq(&worker->lock);
+
+	if (freeit)
+		put_worker(worker);
+	return freeit;
+}
+
+static struct btrfs_work *get_next_work(struct btrfs_worker_thread *worker,
+					struct list_head *prio_head,
+					struct list_head *head)
+{
+	struct btrfs_work *work = NULL;
+	struct list_head *cur = NULL;
+
+	if(!list_empty(prio_head))
+		cur = prio_head->next;
+
+	smp_mb();
+	if (!list_empty(&worker->prio_pending))
+		goto refill;
+
+	if (!list_empty(head))
+		cur = head->next;
+
+	if (cur)
+		goto out;
+
+refill:
+	spin_lock_irq(&worker->lock);
+	list_splice_tail_init(&worker->prio_pending, prio_head);
+	list_splice_tail_init(&worker->pending, head);
+
+	if (!list_empty(prio_head))
+		cur = prio_head->next;
+	else if (!list_empty(head))
+		cur = head->next;
+	spin_unlock_irq(&worker->lock);
+
+	if (!cur)
+		goto out_fail;
+
+out:
+	work = list_entry(cur, struct btrfs_work, list);
+
+out_fail:
+	return work;
+}
+
 /*
  * main loop for servicing work items
  */
 static int worker_loop(void *arg)
 {
 	struct btrfs_worker_thread *worker = arg;
-	struct list_head *cur;
+	struct list_head head;
+	struct list_head prio_head;
 	struct btrfs_work *work;
+
+	INIT_LIST_HEAD(&head);
+	INIT_LIST_HEAD(&prio_head);
+
 	do {
-		spin_lock_irq(&worker->lock);
-again_locked:
+again:
 		while (1) {
-			if (!list_empty(&worker->prio_pending))
-				cur = worker->prio_pending.next;
-			else if (!list_empty(&worker->pending))
-				cur = worker->pending.next;
-			else
+
+
+			work = get_next_work(worker, &prio_head, &head);
+			if (!work)
 				break;
 
-			work = list_entry(cur, struct btrfs_work, list);
 			list_del(&work->list);
 			clear_bit(WORK_QUEUED_BIT, &work->flags);
 
 			work->worker = worker;
-			spin_unlock_irq(&worker->lock);
 
 			work->func(work);
 
@@ -175,9 +329,13 @@ again_locked:
 			 */
 			run_ordered_completions(worker->workers, work);
 
-			spin_lock_irq(&worker->lock);
-			check_idle_worker(worker);
+			check_pending_worker_creates(worker);
+
 		}
+
+		spin_lock_irq(&worker->lock);
+		check_idle_worker(worker);
+
 		if (freezing(current)) {
 			worker->working = 0;
 			spin_unlock_irq(&worker->lock);
@@ -216,8 +374,10 @@ again_locked:
 				spin_lock_irq(&worker->lock);
 				set_current_state(TASK_INTERRUPTIBLE);
 				if (!list_empty(&worker->pending) ||
-				    !list_empty(&worker->prio_pending))
-					goto again_locked;
+				    !list_empty(&worker->prio_pending)) {
+					spin_unlock_irq(&worker->lock);
+					goto again;
+				}
 
 				/*
 				 * this makes sure we get a wakeup when someone
@@ -226,8 +386,13 @@ again_locked:
 				worker->working = 0;
 				spin_unlock_irq(&worker->lock);
 
-				if (!kthread_should_stop())
-					schedule();
+				if (!kthread_should_stop()) {
+					schedule_timeout(HZ * 120);
+					if (!worker->working &&
+					    try_worker_shutdown(worker)) {
+						return 0;
+					}
+				}
 			}
 			__set_current_state(TASK_RUNNING);
 		}
@@ -242,41 +407,61 @@ int btrfs_stop_workers(struct btrfs_workers *workers)
 {
 	struct list_head *cur;
 	struct btrfs_worker_thread *worker;
+	int can_stop;
 
+	spin_lock_irq(&workers->lock);
 	list_splice_init(&workers->idle_list, &workers->worker_list);
 	while (!list_empty(&workers->worker_list)) {
 		cur = workers->worker_list.next;
 		worker = list_entry(cur, struct btrfs_worker_thread,
 				    worker_list);
-		kthread_stop(worker->task);
-		list_del(&worker->worker_list);
-		kfree(worker);
+
+		atomic_inc(&worker->refs);
+		workers->num_workers -= 1;
+		if (!list_empty(&worker->worker_list)) {
+			list_del_init(&worker->worker_list);
+			put_worker(worker);
+			can_stop = 1;
+		} else
+			can_stop = 0;
+		spin_unlock_irq(&workers->lock);
+		if (can_stop)
+			kthread_stop(worker->task);
+		spin_lock_irq(&workers->lock);
+		put_worker(worker);
 	}
+	spin_unlock_irq(&workers->lock);
 	return 0;
 }
 
 /*
  * simple init on struct btrfs_workers
  */
-void btrfs_init_workers(struct btrfs_workers *workers, char *name, int max)
+void btrfs_init_workers(struct btrfs_workers *workers, char *name, int max,
+			struct btrfs_workers *async_helper)
 {
 	workers->num_workers = 0;
+	workers->num_workers_starting = 0;
 	INIT_LIST_HEAD(&workers->worker_list);
 	INIT_LIST_HEAD(&workers->idle_list);
 	INIT_LIST_HEAD(&workers->order_list);
 	INIT_LIST_HEAD(&workers->prio_order_list);
 	spin_lock_init(&workers->lock);
+	spin_lock_init(&workers->order_lock);
 	workers->max_workers = max;
 	workers->idle_thresh = 32;
 	workers->name = name;
 	workers->ordered = 0;
+	workers->atomic_start_pending = 0;
+	workers->atomic_worker_start = async_helper;
 }
 
 /*
  * starts new worker threads.  This does not enforce the max worker
  * count in case you need to temporarily go past it.
  */
-int btrfs_start_workers(struct btrfs_workers *workers, int num_workers)
+static int __btrfs_start_workers(struct btrfs_workers *workers,
+				 int num_workers)
 {
 	struct btrfs_worker_thread *worker;
 	int ret = 0;
@@ -293,7 +478,9 @@ int btrfs_start_workers(struct btrfs_workers *workers, int num_workers)
 		INIT_LIST_HEAD(&worker->prio_pending);
 		INIT_LIST_HEAD(&worker->worker_list);
 		spin_lock_init(&worker->lock);
+
 		atomic_set(&worker->num_pending, 0);
+		atomic_set(&worker->refs, 1);
 		worker->workers = workers;
 		worker->task = kthread_run(worker_loop, worker,
 					   "btrfs-%s-%d", workers->name,
@@ -303,11 +490,12 @@ int btrfs_start_workers(struct btrfs_workers *workers, int num_workers)
 			kfree(worker);
 			goto fail;
 		}
-
 		spin_lock_irq(&workers->lock);
 		list_add_tail(&worker->worker_list, &workers->idle_list);
 		worker->idle = 1;
 		workers->num_workers++;
+		workers->num_workers_starting--;
+		WARN_ON(workers->num_workers_starting < 0);
 		spin_unlock_irq(&workers->lock);
 	}
 	return 0;
@@ -316,6 +504,14 @@ fail:
 	return ret;
 }
 
+int btrfs_start_workers(struct btrfs_workers *workers, int num_workers)
+{
+	spin_lock_irq(&workers->lock);
+	workers->num_workers_starting += num_workers;
+	spin_unlock_irq(&workers->lock);
+	return __btrfs_start_workers(workers, num_workers);
+}
+
 /*
  * run through the list and find a worker thread that doesn't have a lot
  * to do right now.  This can return null if we aren't yet at the thread
@@ -325,7 +521,10 @@ static struct btrfs_worker_thread *next_worker(struct btrfs_workers *workers)
 {
 	struct btrfs_worker_thread *worker;
 	struct list_head *next;
-	int enforce_min = workers->num_workers < workers->max_workers;
+	int enforce_min;
+
+	enforce_min = (workers->num_workers + workers->num_workers_starting) <
+		workers->max_workers;
 
 	/*
 	 * if we find an idle thread, don't move it to the end of the
@@ -350,7 +549,6 @@ static struct btrfs_worker_thread *next_worker(struct btrfs_workers *workers)
 	 */
 	next = workers->worker_list.next;
 	worker = list_entry(next, struct btrfs_worker_thread, worker_list);
-	atomic_inc(&worker->num_pending);
 	worker->sequence++;
 
 	if (worker->sequence % workers->idle_thresh == 0)
@@ -367,35 +565,49 @@ static struct btrfs_worker_thread *find_worker(struct btrfs_workers *workers)
 {
 	struct btrfs_worker_thread *worker;
 	unsigned long flags;
+	struct list_head *fallback;
 
 again:
 	spin_lock_irqsave(&workers->lock, flags);
 	worker = next_worker(workers);
-	spin_unlock_irqrestore(&workers->lock, flags);
 
 	if (!worker) {
-		spin_lock_irqsave(&workers->lock, flags);
-		if (workers->num_workers >= workers->max_workers) {
-			struct list_head *fallback = NULL;
-			/*
-			 * we have failed to find any workers, just
-			 * return the force one
-			 */
-			if (!list_empty(&workers->worker_list))
-				fallback = workers->worker_list.next;
-			if (!list_empty(&workers->idle_list))
-				fallback = workers->idle_list.next;
-			BUG_ON(!fallback);
-			worker = list_entry(fallback,
-				  struct btrfs_worker_thread, worker_list);
-			spin_unlock_irqrestore(&workers->lock, flags);
+		if (workers->num_workers + workers->num_workers_starting >=
+		    workers->max_workers) {
+			goto fallback;
+		} else if (workers->atomic_worker_start) {
+			workers->atomic_start_pending = 1;
+			goto fallback;
 		} else {
+			workers->num_workers_starting++;
 			spin_unlock_irqrestore(&workers->lock, flags);
 			/* we're below the limit, start another worker */
-			btrfs_start_workers(workers, 1);
+			__btrfs_start_workers(workers, 1);
 			goto again;
 		}
 	}
+	goto found;
+
+fallback:
+	fallback = NULL;
+	/*
+	 * we have failed to find any workers, just
+	 * return the first one we can find.
+	 */
+	if (!list_empty(&workers->worker_list))
+		fallback = workers->worker_list.next;
+	if (!list_empty(&workers->idle_list))
+		fallback = workers->idle_list.next;
+	BUG_ON(!fallback);
+	worker = list_entry(fallback,
+		  struct btrfs_worker_thread, worker_list);
+found:
+	/*
+	 * this makes sure the worker doesn't exit before it is placed
+	 * onto a busy/idle list
+	 */
+	atomic_inc(&worker->num_pending);
+	spin_unlock_irqrestore(&workers->lock, flags);
 	return worker;
 }
 
@@ -427,7 +639,7 @@ int btrfs_requeue_work(struct btrfs_work *work)
 		spin_lock(&worker->workers->lock);
 		worker->idle = 0;
 		list_move_tail(&worker->worker_list,
-			       &worker->workers->worker_list);
+			      &worker->workers->worker_list);
 		spin_unlock(&worker->workers->lock);
 	}
 	if (!worker->working) {
@@ -435,9 +647,9 @@ int btrfs_requeue_work(struct btrfs_work *work)
 		worker->working = 1;
 	}
 
-	spin_unlock_irqrestore(&worker->lock, flags);
 	if (wake)
 		wake_up_process(worker->task);
+	spin_unlock_irqrestore(&worker->lock, flags);
 out:
 
 	return 0;
@@ -463,14 +675,18 @@ int btrfs_queue_worker(struct btrfs_workers *workers, struct btrfs_work *work)
 
 	worker = find_worker(workers);
 	if (workers->ordered) {
-		spin_lock_irqsave(&workers->lock, flags);
+		/*
+		 * you're not allowed to do ordered queues from an
+		 * interrupt handler
+		 */
+		spin_lock(&workers->order_lock);
 		if (test_bit(WORK_HIGH_PRIO_BIT, &work->flags)) {
 			list_add_tail(&work->order_list,
 				      &workers->prio_order_list);
 		} else {
 			list_add_tail(&work->order_list, &workers->order_list);
 		}
-		spin_unlock_irqrestore(&workers->lock, flags);
+		spin_unlock(&workers->order_lock);
 	} else {
 		INIT_LIST_HEAD(&work->order_list);
 	}
@@ -481,7 +697,6 @@ int btrfs_queue_worker(struct btrfs_workers *workers, struct btrfs_work *work)
 		list_add_tail(&work->list, &worker->prio_pending);
 	else
 		list_add_tail(&work->list, &worker->pending);
-	atomic_inc(&worker->num_pending);
 	check_busy_worker(worker);
 
 	/*
@@ -492,10 +707,10 @@ int btrfs_queue_worker(struct btrfs_workers *workers, struct btrfs_work *work)
 		wake = 1;
 	worker->working = 1;
 
-	spin_unlock_irqrestore(&worker->lock, flags);
-
 	if (wake)
 		wake_up_process(worker->task);
+	spin_unlock_irqrestore(&worker->lock, flags);
+
 out:
 	return 0;
 }
diff --git a/fs/btrfs/async-thread.h b/fs/btrfs/async-thread.h
index 1b511c1..5077746 100644
--- a/fs/btrfs/async-thread.h
+++ b/fs/btrfs/async-thread.h
@@ -64,6 +64,8 @@ struct btrfs_workers {
 	/* current number of running workers */
 	int num_workers;
 
+	int num_workers_starting;
+
 	/* max number of workers allowed.  changed by btrfs_start_workers */
 	int max_workers;
 
@@ -73,6 +75,16 @@ struct btrfs_workers {
 	/* force completions in the order they were queued */
 	int ordered;
 
+	/* more workers required, but in an interrupt handler */
+	int atomic_start_pending;
+
+	/*
+	 * are we allowed to sleep while starting workers or are we required
+	 * to start them at a later time?  If we can't sleep, this indicates
+	 * which queue we need to use to schedule thread creation.
+	 */
+	struct btrfs_workers *atomic_worker_start;
+
 	/* list with all the work threads.  The workers on the idle thread
 	 * may be actively servicing jobs, but they haven't yet hit the
 	 * idle thresh limit above.
@@ -90,6 +102,9 @@ struct btrfs_workers {
 	/* lock for finding the next worker thread to queue on */
 	spinlock_t lock;
 
+	/* lock for the ordered lists */
+	spinlock_t order_lock;
+
 	/* extra name for this worker, used for current->name */
 	char *name;
 };
@@ -97,7 +112,8 @@ struct btrfs_workers {
 int btrfs_queue_worker(struct btrfs_workers *workers, struct btrfs_work *work);
 int btrfs_start_workers(struct btrfs_workers *workers, int num_workers);
 int btrfs_stop_workers(struct btrfs_workers *workers);
-void btrfs_init_workers(struct btrfs_workers *workers, char *name, int max);
+void btrfs_init_workers(struct btrfs_workers *workers, char *name, int max,
+			struct btrfs_workers *async_starter);
 int btrfs_requeue_work(struct btrfs_work *work);
 void btrfs_set_work_high_prio(struct btrfs_work *work);
 #endif
diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h
index ea1ea0a..f6783a4 100644
--- a/fs/btrfs/btrfs_inode.h
+++ b/fs/btrfs/btrfs_inode.h
@@ -86,6 +86,12 @@ struct btrfs_inode {
 	 * transid of the trans_handle that last modified this inode
 	 */
 	u64 last_trans;
+
+	/*
+	 * log transid when this inode was last modified
+	 */
+	u64 last_sub_trans;
+
 	/*
 	 * transid that last logged this inode
 	 */
@@ -128,6 +134,16 @@ struct btrfs_inode {
 	u64 last_unlink_trans;
 
 	/*
+	 * Counters to keep track of the number of extent item's we may use due
+	 * to delalloc and such.  outstanding_extents is the number of extent
+	 * items we think we'll end up using, and reserved_extents is the number
+	 * of extent items we've reserved metadata for.
+	 */
+	spinlock_t accounting_lock;
+	int reserved_extents;
+	int outstanding_extents;
+
+	/*
 	 * ordered_data_close is set by truncate when a file that used
 	 * to have good data has been truncated to zero.  When it is set
 	 * the btrfs file release call will add this inode to the
@@ -138,6 +154,7 @@ struct btrfs_inode {
 	 * of these.
 	 */
 	unsigned ordered_data_close:1;
+	unsigned dummy_inode:1;
 
 	struct inode vfs_inode;
 };
diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index 9d8ba4d..a11a320 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -506,10 +506,10 @@ static noinline int add_ra_bio_pages(struct inode *inode,
 		 */
 		set_page_extent_mapped(page);
 		lock_extent(tree, last_offset, end, GFP_NOFS);
-		spin_lock(&em_tree->lock);
+		read_lock(&em_tree->lock);
 		em = lookup_extent_mapping(em_tree, last_offset,
 					   PAGE_CACHE_SIZE);
-		spin_unlock(&em_tree->lock);
+		read_unlock(&em_tree->lock);
 
 		if (!em || last_offset < em->start ||
 		    (last_offset + PAGE_CACHE_SIZE > extent_map_end(em)) ||
@@ -593,11 +593,11 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 	em_tree = &BTRFS_I(inode)->extent_tree;
 
 	/* we need the actual starting offset of this extent in the file */
-	spin_lock(&em_tree->lock);
+	read_lock(&em_tree->lock);
 	em = lookup_extent_mapping(em_tree,
 				   page_offset(bio->bi_io_vec->bv_page),
 				   PAGE_CACHE_SIZE);
-	spin_unlock(&em_tree->lock);
+	read_unlock(&em_tree->lock);
 
 	compressed_len = em->block_len;
 	cb = kmalloc(compressed_bio_size(root, compressed_len), GFP_NOFS);
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 3fdcc05..ec96f3a 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -2853,6 +2853,12 @@ static noinline int split_leaf(struct btrfs_trans_handle *trans,
 	int split;
 	int num_doubles = 0;
 
+	l = path->nodes[0];
+	slot = path->slots[0];
+	if (extend && data_size + btrfs_item_size_nr(l, slot) +
+	    sizeof(struct btrfs_item) > BTRFS_LEAF_DATA_SIZE(root))
+		return -EOVERFLOW;
+
 	/* first try to make some room by pushing left and right */
 	if (data_size && ins_key->type != BTRFS_DIR_ITEM_KEY) {
 		wret = push_leaf_right(trans, root, path, data_size, 0);
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 837435c..444b3e9 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -114,6 +114,10 @@ struct btrfs_ordered_sum;
  */
 #define BTRFS_DEV_ITEMS_OBJECTID 1ULL
 
+#define BTRFS_BTREE_INODE_OBJECTID 1
+
+#define BTRFS_EMPTY_SUBVOL_DIR_OBJECTID 2
+
 /*
  * we can actually store much bigger names, but lets not confuse the rest
  * of linux
@@ -670,21 +674,29 @@ struct btrfs_space_info {
 	u64 bytes_reserved;	/* total bytes the allocator has reserved for
 				   current allocations */
 	u64 bytes_readonly;	/* total bytes that are read only */
-
-	/* delalloc accounting */
-	u64 bytes_delalloc;	/* number of bytes reserved for allocation,
-				   this space is not necessarily reserved yet
-				   by the allocator */
+	u64 bytes_super;	/* total bytes reserved for the super blocks */
+	u64 bytes_root;		/* the number of bytes needed to commit a
+				   transaction */
 	u64 bytes_may_use;	/* number of bytes that may be used for
-				   delalloc */
+				   delalloc/allocations */
+	u64 bytes_delalloc;	/* number of bytes currently reserved for
+				   delayed allocation */
 
 	int full;		/* indicates that we cannot allocate any more
 				   chunks for this space */
 	int force_alloc;	/* set if we need to force a chunk alloc for
 				   this space */
+	int force_delalloc;	/* make people start doing filemap_flush until
+				   we're under a threshold */
 
 	struct list_head list;
 
+	/* for controlling how we free up space for allocations */
+	wait_queue_head_t allocate_wait;
+	wait_queue_head_t flush_wait;
+	int allocating_chunk;
+	int flushing;
+
 	/* for block groups in our same type */
 	struct list_head block_groups;
 	spinlock_t lock;
@@ -726,6 +738,15 @@ enum btrfs_caching_type {
 	BTRFS_CACHE_FINISHED	= 2,
 };
 
+struct btrfs_caching_control {
+	struct list_head list;
+	struct mutex mutex;
+	wait_queue_head_t wait;
+	struct btrfs_block_group_cache *block_group;
+	u64 progress;
+	atomic_t count;
+};
+
 struct btrfs_block_group_cache {
 	struct btrfs_key key;
 	struct btrfs_block_group_item item;
@@ -733,6 +754,7 @@ struct btrfs_block_group_cache {
 	spinlock_t lock;
 	u64 pinned;
 	u64 reserved;
+	u64 bytes_super;
 	u64 flags;
 	u64 sectorsize;
 	int extents_thresh;
@@ -742,8 +764,9 @@ struct btrfs_block_group_cache {
 	int dirty;
 
 	/* cache tracking stuff */
-	wait_queue_head_t caching_q;
 	int cached;
+	struct btrfs_caching_control *caching_ctl;
+	u64 last_byte_to_unpin;
 
 	struct btrfs_space_info *space_info;
 
@@ -782,13 +805,16 @@ struct btrfs_fs_info {
 
 	/* the log root tree is a directory of all the other log roots */
 	struct btrfs_root *log_root_tree;
+
+	spinlock_t fs_roots_radix_lock;
 	struct radix_tree_root fs_roots_radix;
 
 	/* block group cache stuff */
 	spinlock_t block_group_cache_lock;
 	struct rb_root block_group_cache_tree;
 
-	struct extent_io_tree pinned_extents;
+	struct extent_io_tree freed_extents[2];
+	struct extent_io_tree *pinned_extents;
 
 	/* logical->physical extent mapping */
 	struct btrfs_mapping_tree mapping_tree;
@@ -822,11 +848,7 @@ struct btrfs_fs_info {
 	struct mutex transaction_kthread_mutex;
 	struct mutex cleaner_mutex;
 	struct mutex chunk_mutex;
-	struct mutex drop_mutex;
 	struct mutex volume_mutex;
-	struct mutex tree_reloc_mutex;
-	struct rw_semaphore extent_commit_sem;
-
 	/*
 	 * this protects the ordered operations list only while we are
 	 * processing all of the entries on it.  This way we make
@@ -835,10 +857,16 @@ struct btrfs_fs_info {
 	 * before jumping into the main commit.
 	 */
 	struct mutex ordered_operations_mutex;
+	struct rw_semaphore extent_commit_sem;
+
+	struct rw_semaphore subvol_sem;
+
+	struct srcu_struct subvol_srcu;
 
 	struct list_head trans_list;
 	struct list_head hashers;
 	struct list_head dead_roots;
+	struct list_head caching_block_groups;
 
 	atomic_t nr_async_submits;
 	atomic_t async_submit_draining;
@@ -882,6 +910,7 @@ struct btrfs_fs_info {
 	 * A third pool does submit_bio to avoid deadlocking with the other
 	 * two
 	 */
+	struct btrfs_workers generic_worker;
 	struct btrfs_workers workers;
 	struct btrfs_workers delalloc_workers;
 	struct btrfs_workers endio_workers;
@@ -889,6 +918,7 @@ struct btrfs_fs_info {
 	struct btrfs_workers endio_meta_write_workers;
 	struct btrfs_workers endio_write_workers;
 	struct btrfs_workers submit_workers;
+	struct btrfs_workers enospc_workers;
 	/*
 	 * fixup workers take dirty pages that didn't properly go through
 	 * the cow mechanism and make them safe to write.  It happens
@@ -979,7 +1009,10 @@ struct btrfs_root {
 	atomic_t log_writers;
 	atomic_t log_commit[2];
 	unsigned long log_transid;
+	unsigned long last_log_commit;
 	unsigned long log_batch;
+	pid_t log_start_pid;
+	bool log_multiple_pids;
 
 	u64 objectid;
 	u64 last_trans;
@@ -996,10 +1029,12 @@ struct btrfs_root {
 	u32 stripesize;
 
 	u32 type;
-	u64 highest_inode;
-	u64 last_inode_alloc;
+
+	u64 highest_objectid;
 	int ref_cows;
 	int track_dirty;
+	int in_radix;
+
 	u64 defrag_trans_start;
 	struct btrfs_key defrag_progress;
 	struct btrfs_key defrag_max;
@@ -1118,6 +1153,7 @@ struct btrfs_root {
 #define BTRFS_MOUNT_FLUSHONCOMMIT       (1 << 7)
 #define BTRFS_MOUNT_SSD_SPREAD		(1 << 8)
 #define BTRFS_MOUNT_NOSSD		(1 << 9)
+#define BTRFS_MOUNT_DISCARD		(1 << 10)
 
 #define btrfs_clear_opt(o, opt)		((o) &= ~BTRFS_MOUNT_##opt)
 #define btrfs_set_opt(o, opt)		((o) |= BTRFS_MOUNT_##opt)
@@ -1920,8 +1956,8 @@ void btrfs_put_block_group(struct btrfs_block_group_cache *cache);
 int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
 			   struct btrfs_root *root, unsigned long count);
 int btrfs_lookup_extent(struct btrfs_root *root, u64 start, u64 len);
-int btrfs_update_pinned_extents(struct btrfs_root *root,
-				u64 bytenr, u64 num, int pin);
+int btrfs_pin_extent(struct btrfs_root *root,
+		     u64 bytenr, u64 num, int reserved);
 int btrfs_drop_leaf_ref(struct btrfs_trans_handle *trans,
 			struct btrfs_root *root, struct extent_buffer *leaf);
 int btrfs_cross_ref_exist(struct btrfs_trans_handle *trans,
@@ -1971,9 +2007,10 @@ int btrfs_free_extent(struct btrfs_trans_handle *trans,
 		      u64 root_objectid, u64 owner, u64 offset);
 
 int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len);
+int btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,
+				struct btrfs_root *root);
 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
-			       struct btrfs_root *root,
-			       struct extent_io_tree *unpin);
+			       struct btrfs_root *root);
 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
 			 struct btrfs_root *root,
 			 u64 bytenr, u64 num_bytes, u64 parent,
@@ -1984,6 +2021,7 @@ int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
 int btrfs_extent_readonly(struct btrfs_root *root, u64 bytenr);
 int btrfs_free_block_groups(struct btrfs_fs_info *info);
 int btrfs_read_block_groups(struct btrfs_root *root);
+int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr);
 int btrfs_make_block_group(struct btrfs_trans_handle *trans,
 			   struct btrfs_root *root, u64 bytes_used,
 			   u64 type, u64 chunk_objectid, u64 chunk_offset,
@@ -1997,7 +2035,12 @@ u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags);
 void btrfs_set_inode_space_info(struct btrfs_root *root, struct inode *ionde);
 void btrfs_clear_space_info_full(struct btrfs_fs_info *info);
 
-int btrfs_check_metadata_free_space(struct btrfs_root *root);
+int btrfs_reserve_metadata_space(struct btrfs_root *root, int num_items);
+int btrfs_unreserve_metadata_space(struct btrfs_root *root, int num_items);
+int btrfs_unreserve_metadata_for_delalloc(struct btrfs_root *root,
+					  struct inode *inode, int num_items);
+int btrfs_reserve_metadata_for_delalloc(struct btrfs_root *root,
+					struct inode *inode, int num_items);
 int btrfs_check_data_free_space(struct btrfs_root *root, struct inode *inode,
 				u64 bytes);
 void btrfs_free_reserved_data_space(struct btrfs_root *root,
@@ -2006,7 +2049,6 @@ void btrfs_delalloc_reserve_space(struct btrfs_root *root, struct inode *inode,
 				 u64 bytes);
 void btrfs_delalloc_free_space(struct btrfs_root *root, struct inode *inode,
 			      u64 bytes);
-void btrfs_free_pinned_extents(struct btrfs_fs_info *info);
 /* ctree.c */
 int btrfs_bin_search(struct extent_buffer *eb, struct btrfs_key *key,
 		     int level, int *slot);
@@ -2100,12 +2142,15 @@ int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
 			struct extent_buffer *parent);
 /* root-item.c */
 int btrfs_find_root_ref(struct btrfs_root *tree_root,
-		   struct btrfs_path *path,
-		   u64 root_id, u64 ref_id);
+			struct btrfs_path *path,
+			u64 root_id, u64 ref_id);
 int btrfs_add_root_ref(struct btrfs_trans_handle *trans,
 		       struct btrfs_root *tree_root,
-		       u64 root_id, u8 type, u64 ref_id,
-		       u64 dirid, u64 sequence,
+		       u64 root_id, u64 ref_id, u64 dirid, u64 sequence,
+		       const char *name, int name_len);
+int btrfs_del_root_ref(struct btrfs_trans_handle *trans,
+		       struct btrfs_root *tree_root,
+		       u64 root_id, u64 ref_id, u64 dirid, u64 *sequence,
 		       const char *name, int name_len);
 int btrfs_del_root(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 		   struct btrfs_key *key);
@@ -2120,6 +2165,7 @@ int btrfs_find_last_root(struct btrfs_root *root, u64 objectid, struct
 int btrfs_search_root(struct btrfs_root *root, u64 search_start,
 		      u64 *found_objectid);
 int btrfs_find_dead_roots(struct btrfs_root *root, u64 objectid);
+int btrfs_find_orphan_roots(struct btrfs_root *tree_root);
 int btrfs_set_root_node(struct btrfs_root_item *item,
 			struct extent_buffer *node);
 /* dir-item.c */
@@ -2138,6 +2184,10 @@ btrfs_lookup_dir_index_item(struct btrfs_trans_handle *trans,
 			    struct btrfs_path *path, u64 dir,
 			    u64 objectid, const char *name, int name_len,
 			    int mod);
+struct btrfs_dir_item *
+btrfs_search_dir_index_item(struct btrfs_root *root,
+			    struct btrfs_path *path, u64 dirid,
+			    const char *name, int name_len);
 struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_root *root,
 			      struct btrfs_path *path,
 			      const char *name, int name_len);
@@ -2160,6 +2210,7 @@ int btrfs_insert_orphan_item(struct btrfs_trans_handle *trans,
 			     struct btrfs_root *root, u64 offset);
 int btrfs_del_orphan_item(struct btrfs_trans_handle *trans,
 			  struct btrfs_root *root, u64 offset);
+int btrfs_find_orphan_item(struct btrfs_root *root, u64 offset);
 
 /* inode-map.c */
 int btrfs_find_free_objectid(struct btrfs_trans_handle *trans,
@@ -2232,6 +2283,10 @@ int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
 int btrfs_add_link(struct btrfs_trans_handle *trans,
 		   struct inode *parent_inode, struct inode *inode,
 		   const char *name, int name_len, int add_backref, u64 index);
+int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
+			struct btrfs_root *root,
+			struct inode *dir, u64 objectid,
+			const char *name, int name_len);
 int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
 			       struct btrfs_root *root,
 			       struct inode *inode, u64 new_size,
@@ -2242,7 +2297,7 @@ int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end);
 int btrfs_writepages(struct address_space *mapping,
 		     struct writeback_control *wbc);
 int btrfs_create_subvol_root(struct btrfs_trans_handle *trans,
-			     struct btrfs_root *new_root, struct dentry *dentry,
+			     struct btrfs_root *new_root,
 			     u64 new_dirid, u64 alloc_hint);
 int btrfs_merge_bio_hook(struct page *page, unsigned long offset,
 			 size_t size, struct bio *bio, unsigned long bio_flags);
@@ -2258,6 +2313,7 @@ int btrfs_write_inode(struct inode *inode, int wait);
 void btrfs_dirty_inode(struct inode *inode);
 struct inode *btrfs_alloc_inode(struct super_block *sb);
 void btrfs_destroy_inode(struct inode *inode);
+void btrfs_drop_inode(struct inode *inode);
 int btrfs_init_cachep(void);
 void btrfs_destroy_cachep(void);
 long btrfs_ioctl_trans_end(struct file *file);
@@ -2275,6 +2331,8 @@ int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode);
 int btrfs_orphan_del(struct btrfs_trans_handle *trans, struct inode *inode);
 void btrfs_orphan_cleanup(struct btrfs_root *root);
 int btrfs_cont_expand(struct inode *inode, loff_t size);
+int btrfs_invalidate_inodes(struct btrfs_root *root);
+extern const struct dentry_operations btrfs_dentry_operations;
 
 /* ioctl.c */
 long btrfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
@@ -2286,11 +2344,11 @@ int btrfs_sync_file(struct file *file, struct dentry *dentry, int datasync);
 int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end,
 			    int skip_pinned);
 int btrfs_check_file(struct btrfs_root *root, struct inode *inode);
-extern struct file_operations btrfs_file_operations;
+extern const struct file_operations btrfs_file_operations;
 int btrfs_drop_extents(struct btrfs_trans_handle *trans,
 		       struct btrfs_root *root, struct inode *inode,
 		       u64 start, u64 end, u64 locked_end,
-		       u64 inline_limit, u64 *hint_block);
+		       u64 inline_limit, u64 *hint_block, int drop_cache);
 int btrfs_mark_extent_written(struct btrfs_trans_handle *trans,
 			      struct btrfs_root *root,
 			      struct inode *inode, u64 start, u64 end);
@@ -2317,7 +2375,7 @@ int btrfs_parse_options(struct btrfs_root *root, char *options);
 int btrfs_sync_fs(struct super_block *sb, int wait);
 
 /* acl.c */
-#ifdef CONFIG_FS_POSIX_ACL
+#ifdef CONFIG_BTRFS_FS_POSIX_ACL
 int btrfs_check_acl(struct inode *inode, int mask);
 #else
 #define btrfs_check_acl NULL
diff --git a/fs/btrfs/dir-item.c b/fs/btrfs/dir-item.c
index 1d70236..f3a6075 100644
--- a/fs/btrfs/dir-item.c
+++ b/fs/btrfs/dir-item.c
@@ -281,6 +281,53 @@ btrfs_lookup_dir_index_item(struct btrfs_trans_handle *trans,
 	return btrfs_match_dir_item_name(root, path, name, name_len);
 }
 
+struct btrfs_dir_item *
+btrfs_search_dir_index_item(struct btrfs_root *root,
+			    struct btrfs_path *path, u64 dirid,
+			    const char *name, int name_len)
+{
+	struct extent_buffer *leaf;
+	struct btrfs_dir_item *di;
+	struct btrfs_key key;
+	u32 nritems;
+	int ret;
+
+	key.objectid = dirid;
+	key.type = BTRFS_DIR_INDEX_KEY;
+	key.offset = 0;
+
+	ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
+	if (ret < 0)
+		return ERR_PTR(ret);
+
+	leaf = path->nodes[0];
+	nritems = btrfs_header_nritems(leaf);
+
+	while (1) {
+		if (path->slots[0] >= nritems) {
+			ret = btrfs_next_leaf(root, path);
+			if (ret < 0)
+				return ERR_PTR(ret);
+			if (ret > 0)
+				break;
+			leaf = path->nodes[0];
+			nritems = btrfs_header_nritems(leaf);
+			continue;
+		}
+
+		btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
+		if (key.objectid != dirid || key.type != BTRFS_DIR_INDEX_KEY)
+			break;
+
+		di = btrfs_match_dir_item_name(root, path, name, name_len);
+		if (di)
+			return di;
+
+		path->slots[0]++;
+	}
+	return NULL;
+}
+
 struct btrfs_dir_item *btrfs_lookup_xattr(struct btrfs_trans_handle *trans,
 					  struct btrfs_root *root,
 					  struct btrfs_path *path, u64 dir,
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 6c41731..02b6afb 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -41,6 +41,7 @@
 
 static struct extent_io_ops btree_extent_io_ops;
 static void end_workqueue_fn(struct btrfs_work *work);
+static void free_fs_root(struct btrfs_root *root);
 
 static atomic_t btrfs_bdi_num = ATOMIC_INIT(0);
 
@@ -123,15 +124,15 @@ static struct extent_map *btree_get_extent(struct inode *inode,
 	struct extent_map *em;
 	int ret;
 
-	spin_lock(&em_tree->lock);
+	read_lock(&em_tree->lock);
 	em = lookup_extent_mapping(em_tree, start, len);
 	if (em) {
 		em->bdev =
 			BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
-		spin_unlock(&em_tree->lock);
+		read_unlock(&em_tree->lock);
 		goto out;
 	}
-	spin_unlock(&em_tree->lock);
+	read_unlock(&em_tree->lock);
 
 	em = alloc_extent_map(GFP_NOFS);
 	if (!em) {
@@ -144,7 +145,7 @@ static struct extent_map *btree_get_extent(struct inode *inode,
 	em->block_start = 0;
 	em->bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
 
-	spin_lock(&em_tree->lock);
+	write_lock(&em_tree->lock);
 	ret = add_extent_mapping(em_tree, em);
 	if (ret == -EEXIST) {
 		u64 failed_start = em->start;
@@ -163,7 +164,7 @@ static struct extent_map *btree_get_extent(struct inode *inode,
 		free_extent_map(em);
 		em = NULL;
 	}
-	spin_unlock(&em_tree->lock);
+	write_unlock(&em_tree->lock);
 
 	if (ret)
 		em = ERR_PTR(ret);
@@ -821,14 +822,14 @@ struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
 
 int btrfs_write_tree_block(struct extent_buffer *buf)
 {
-	return btrfs_fdatawrite_range(buf->first_page->mapping, buf->start,
-				      buf->start + buf->len - 1, WB_SYNC_ALL);
+	return filemap_fdatawrite_range(buf->first_page->mapping, buf->start,
+					buf->start + buf->len - 1);
 }
 
 int btrfs_wait_tree_block_writeback(struct extent_buffer *buf)
 {
-	return btrfs_wait_on_page_writeback_range(buf->first_page->mapping,
-				  buf->start, buf->start + buf->len - 1);
+	return filemap_fdatawait_range(buf->first_page->mapping,
+				       buf->start, buf->start + buf->len - 1);
 }
 
 struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
@@ -895,8 +896,7 @@ static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
 	root->fs_info = fs_info;
 	root->objectid = objectid;
 	root->last_trans = 0;
-	root->highest_inode = 0;
-	root->last_inode_alloc = 0;
+	root->highest_objectid = 0;
 	root->name = NULL;
 	root->in_sysfs = 0;
 	root->inode_tree.rb_node = NULL;
@@ -917,6 +917,7 @@ static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
 	atomic_set(&root->log_writers, 0);
 	root->log_batch = 0;
 	root->log_transid = 0;
+	root->last_log_commit = 0;
 	extent_io_tree_init(&root->dirty_log_pages,
 			     fs_info->btree_inode->i_mapping, GFP_NOFS);
 
@@ -952,14 +953,16 @@ static int find_and_setup_root(struct btrfs_root *tree_root,
 		     root, fs_info, objectid);
 	ret = btrfs_find_last_root(tree_root, objectid,
 				   &root->root_item, &root->root_key);
+	if (ret > 0)
+		return -ENOENT;
 	BUG_ON(ret);
 
 	generation = btrfs_root_generation(&root->root_item);
 	blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
 	root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
 				     blocksize, generation);
-	root->commit_root = btrfs_root_node(root);
 	BUG_ON(!root->node);
+	root->commit_root = btrfs_root_node(root);
 	return 0;
 }
 
@@ -1085,6 +1088,7 @@ int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
 	WARN_ON(root->log_root);
 	root->log_root = log_root;
 	root->log_transid = 0;
+	root->last_log_commit = 0;
 	return 0;
 }
 
@@ -1095,7 +1099,6 @@ struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root,
 	struct btrfs_fs_info *fs_info = tree_root->fs_info;
 	struct btrfs_path *path;
 	struct extent_buffer *l;
-	u64 highest_inode;
 	u64 generation;
 	u32 blocksize;
 	int ret = 0;
@@ -1110,7 +1113,7 @@ struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root,
 			kfree(root);
 			return ERR_PTR(ret);
 		}
-		goto insert;
+		goto out;
 	}
 
 	__setup_root(tree_root->nodesize, tree_root->leafsize,
@@ -1120,39 +1123,30 @@ struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root,
 	path = btrfs_alloc_path();
 	BUG_ON(!path);
 	ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
-	if (ret != 0) {
-		if (ret > 0)
-			ret = -ENOENT;
-		goto out;
+	if (ret == 0) {
+		l = path->nodes[0];
+		read_extent_buffer(l, &root->root_item,
+				btrfs_item_ptr_offset(l, path->slots[0]),
+				sizeof(root->root_item));
+		memcpy(&root->root_key, location, sizeof(*location));
 	}
-	l = path->nodes[0];
-	read_extent_buffer(l, &root->root_item,
-	       btrfs_item_ptr_offset(l, path->slots[0]),
-	       sizeof(root->root_item));
-	memcpy(&root->root_key, location, sizeof(*location));
-	ret = 0;
-out:
-	btrfs_release_path(root, path);
 	btrfs_free_path(path);
 	if (ret) {
-		kfree(root);
+		if (ret > 0)
+			ret = -ENOENT;
 		return ERR_PTR(ret);
 	}
+
 	generation = btrfs_root_generation(&root->root_item);
 	blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
 	root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
 				     blocksize, generation);
 	root->commit_root = btrfs_root_node(root);
 	BUG_ON(!root->node);
-insert:
-	if (location->objectid != BTRFS_TREE_LOG_OBJECTID) {
+out:
+	if (location->objectid != BTRFS_TREE_LOG_OBJECTID)
 		root->ref_cows = 1;
-		ret = btrfs_find_highest_inode(root, &highest_inode);
-		if (ret == 0) {
-			root->highest_inode = highest_inode;
-			root->last_inode_alloc = highest_inode;
-		}
-	}
+
 	return root;
 }
 
@@ -1187,39 +1181,66 @@ struct btrfs_root *btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info,
 		return fs_info->dev_root;
 	if (location->objectid == BTRFS_CSUM_TREE_OBJECTID)
 		return fs_info->csum_root;
-
+again:
+	spin_lock(&fs_info->fs_roots_radix_lock);
 	root = radix_tree_lookup(&fs_info->fs_roots_radix,
 				 (unsigned long)location->objectid);
+	spin_unlock(&fs_info->fs_roots_radix_lock);
 	if (root)
 		return root;
 
+	ret = btrfs_find_orphan_item(fs_info->tree_root, location->objectid);
+	if (ret == 0)
+		ret = -ENOENT;
+	if (ret < 0)
+		return ERR_PTR(ret);
+
 	root = btrfs_read_fs_root_no_radix(fs_info->tree_root, location);
 	if (IS_ERR(root))
 		return root;
 
+	WARN_ON(btrfs_root_refs(&root->root_item) == 0);
 	set_anon_super(&root->anon_super, NULL);
 
+	ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
+	if (ret)
+		goto fail;
+
+	spin_lock(&fs_info->fs_roots_radix_lock);
 	ret = radix_tree_insert(&fs_info->fs_roots_radix,
 				(unsigned long)root->root_key.objectid,
 				root);
+	if (ret == 0)
+		root->in_radix = 1;
+	spin_unlock(&fs_info->fs_roots_radix_lock);
+	radix_tree_preload_end();
 	if (ret) {
-		free_extent_buffer(root->node);
-		kfree(root);
-		return ERR_PTR(ret);
+		if (ret == -EEXIST) {
+			free_fs_root(root);
+			goto again;
+		}
+		goto fail;
 	}
-	if (!(fs_info->sb->s_flags & MS_RDONLY)) {
-		ret = btrfs_find_dead_roots(fs_info->tree_root,
-					    root->root_key.objectid);
-		BUG_ON(ret);
+
+	ret = btrfs_find_dead_roots(fs_info->tree_root,
+				    root->root_key.objectid);
+	WARN_ON(ret);
+
+	if (!(fs_info->sb->s_flags & MS_RDONLY))
 		btrfs_orphan_cleanup(root);
-	}
+
 	return root;
+fail:
+	free_fs_root(root);
+	return ERR_PTR(ret);
 }
 
 struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
 				      struct btrfs_key *location,
 				      const char *name, int namelen)
 {
+	return btrfs_read_fs_root_no_name(fs_info, location);
+#if 0
 	struct btrfs_root *root;
 	int ret;
 
@@ -1236,7 +1257,7 @@ struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
 		kfree(root);
 		return ERR_PTR(ret);
 	}
-#if 0
+
 	ret = btrfs_sysfs_add_root(root);
 	if (ret) {
 		free_extent_buffer(root->node);
@@ -1244,9 +1265,9 @@ struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
 		kfree(root);
 		return ERR_PTR(ret);
 	}
-#endif
 	root->in_sysfs = 1;
 	return root;
+#endif
 }
 
 static int btrfs_congested_fn(void *congested_data, int bdi_bits)
@@ -1325,9 +1346,9 @@ static void btrfs_unplug_io_fn(struct backing_dev_info *bdi, struct page *page)
 	offset = page_offset(page);
 
 	em_tree = &BTRFS_I(inode)->extent_tree;
-	spin_lock(&em_tree->lock);
+	read_lock(&em_tree->lock);
 	em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
-	spin_unlock(&em_tree->lock);
+	read_unlock(&em_tree->lock);
 	if (!em) {
 		__unplug_io_fn(bdi, page);
 		return;
@@ -1360,8 +1381,10 @@ static int setup_bdi(struct btrfs_fs_info *info, struct backing_dev_info *bdi)
 
 	err = bdi_register(bdi, NULL, "btrfs-%d",
 				atomic_inc_return(&btrfs_bdi_num));
-	if (err)
+	if (err) {
+		bdi_destroy(bdi);
 		return err;
+	}
 
 	bdi->ra_pages	= default_backing_dev_info.ra_pages;
 	bdi->unplug_io_fn	= btrfs_unplug_io_fn;
@@ -1451,9 +1474,12 @@ static int cleaner_kthread(void *arg)
 			break;
 
 		vfs_check_frozen(root->fs_info->sb, SB_FREEZE_WRITE);
-		mutex_lock(&root->fs_info->cleaner_mutex);
-		btrfs_clean_old_snapshots(root);
-		mutex_unlock(&root->fs_info->cleaner_mutex);
+
+		if (!(root->fs_info->sb->s_flags & MS_RDONLY) &&
+		    mutex_trylock(&root->fs_info->cleaner_mutex)) {
+			btrfs_clean_old_snapshots(root);
+			mutex_unlock(&root->fs_info->cleaner_mutex);
+		}
 
 		if (freezing(current)) {
 			refrigerator();
@@ -1558,15 +1584,36 @@ struct btrfs_root *open_ctree(struct super_block *sb,
 		err = -ENOMEM;
 		goto fail;
 	}
-	INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_NOFS);
+
+	ret = init_srcu_struct(&fs_info->subvol_srcu);
+	if (ret) {
+		err = ret;
+		goto fail;
+	}
+
+	ret = setup_bdi(fs_info, &fs_info->bdi);
+	if (ret) {
+		err = ret;
+		goto fail_srcu;
+	}
+
+	fs_info->btree_inode = new_inode(sb);
+	if (!fs_info->btree_inode) {
+		err = -ENOMEM;
+		goto fail_bdi;
+	}
+
+	INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
 	INIT_LIST_HEAD(&fs_info->trans_list);
 	INIT_LIST_HEAD(&fs_info->dead_roots);
 	INIT_LIST_HEAD(&fs_info->hashers);
 	INIT_LIST_HEAD(&fs_info->delalloc_inodes);
 	INIT_LIST_HEAD(&fs_info->ordered_operations);
+	INIT_LIST_HEAD(&fs_info->caching_block_groups);
 	spin_lock_init(&fs_info->delalloc_lock);
 	spin_lock_init(&fs_info->new_trans_lock);
 	spin_lock_init(&fs_info->ref_cache_lock);
+	spin_lock_init(&fs_info->fs_roots_radix_lock);
 
 	init_completion(&fs_info->kobj_unregister);
 	fs_info->tree_root = tree_root;
@@ -1585,12 +1632,7 @@ struct btrfs_root *open_ctree(struct super_block *sb,
 	fs_info->sb = sb;
 	fs_info->max_extent = (u64)-1;
 	fs_info->max_inline = 8192 * 1024;
-	if (setup_bdi(fs_info, &fs_info->bdi))
-		goto fail_bdi;
-	fs_info->btree_inode = new_inode(sb);
-	fs_info->btree_inode->i_ino = 1;
-	fs_info->btree_inode->i_nlink = 1;
-	fs_info->metadata_ratio = 8;
+	fs_info->metadata_ratio = 0;
 
 	fs_info->thread_pool_size = min_t(unsigned long,
 					  num_online_cpus() + 2, 8);
@@ -1602,6 +1644,8 @@ struct btrfs_root *open_ctree(struct super_block *sb,
 	sb->s_blocksize_bits = blksize_bits(4096);
 	sb->s_bdi = &fs_info->bdi;
 
+	fs_info->btree_inode->i_ino = BTRFS_BTREE_INODE_OBJECTID;
+	fs_info->btree_inode->i_nlink = 1;
 	/*
 	 * we set the i_size on the btree inode to the max possible int.
 	 * the real end of the address space is determined by all of
@@ -1620,28 +1664,32 @@ struct btrfs_root *open_ctree(struct super_block *sb,
 
 	BTRFS_I(fs_info->btree_inode)->io_tree.ops = &btree_extent_io_ops;
 
+	BTRFS_I(fs_info->btree_inode)->root = tree_root;
+	memset(&BTRFS_I(fs_info->btree_inode)->location, 0,
+	       sizeof(struct btrfs_key));
+	BTRFS_I(fs_info->btree_inode)->dummy_inode = 1;
+	insert_inode_hash(fs_info->btree_inode);
+
 	spin_lock_init(&fs_info->block_group_cache_lock);
 	fs_info->block_group_cache_tree.rb_node = NULL;
 
-	extent_io_tree_init(&fs_info->pinned_extents,
+	extent_io_tree_init(&fs_info->freed_extents[0],
 			     fs_info->btree_inode->i_mapping, GFP_NOFS);
+	extent_io_tree_init(&fs_info->freed_extents[1],
+			     fs_info->btree_inode->i_mapping, GFP_NOFS);
+	fs_info->pinned_extents = &fs_info->freed_extents[0];
 	fs_info->do_barriers = 1;
 
-	BTRFS_I(fs_info->btree_inode)->root = tree_root;
-	memset(&BTRFS_I(fs_info->btree_inode)->location, 0,
-	       sizeof(struct btrfs_key));
-	insert_inode_hash(fs_info->btree_inode);
 
 	mutex_init(&fs_info->trans_mutex);
 	mutex_init(&fs_info->ordered_operations_mutex);
 	mutex_init(&fs_info->tree_log_mutex);
-	mutex_init(&fs_info->drop_mutex);
 	mutex_init(&fs_info->chunk_mutex);
 	mutex_init(&fs_info->transaction_kthread_mutex);
 	mutex_init(&fs_info->cleaner_mutex);
 	mutex_init(&fs_info->volume_mutex);
-	mutex_init(&fs_info->tree_reloc_mutex);
 	init_rwsem(&fs_info->extent_commit_sem);
+	init_rwsem(&fs_info->subvol_sem);
 
 	btrfs_init_free_cluster(&fs_info->meta_alloc_cluster);
 	btrfs_init_free_cluster(&fs_info->data_alloc_cluster);
@@ -1701,20 +1749,24 @@ struct btrfs_root *open_ctree(struct super_block *sb,
 		goto fail_iput;
 	}
 
-	/*
-	 * we need to start all the end_io workers up front because the
-	 * queue work function gets called at interrupt time, and so it
-	 * cannot dynamically grow.
-	 */
+	btrfs_init_workers(&fs_info->generic_worker,
+			   "genwork", 1, NULL);
+
 	btrfs_init_workers(&fs_info->workers, "worker",
-			   fs_info->thread_pool_size);
+			   fs_info->thread_pool_size,
+			   &fs_info->generic_worker);
 
 	btrfs_init_workers(&fs_info->delalloc_workers, "delalloc",
-			   fs_info->thread_pool_size);
+			   fs_info->thread_pool_size,
+			   &fs_info->generic_worker);
 
 	btrfs_init_workers(&fs_info->submit_workers, "submit",
 			   min_t(u64, fs_devices->num_devices,
-			   fs_info->thread_pool_size));
+			   fs_info->thread_pool_size),
+			   &fs_info->generic_worker);
+	btrfs_init_workers(&fs_info->enospc_workers, "enospc",
+			   fs_info->thread_pool_size,
+			   &fs_info->generic_worker);
 
 	/* a higher idle thresh on the submit workers makes it much more
 	 * likely that bios will be send down in a sane order to the
@@ -1728,15 +1780,20 @@ struct btrfs_root *open_ctree(struct super_block *sb,
 	fs_info->delalloc_workers.idle_thresh = 2;
 	fs_info->delalloc_workers.ordered = 1;
 
-	btrfs_init_workers(&fs_info->fixup_workers, "fixup", 1);
+	btrfs_init_workers(&fs_info->fixup_workers, "fixup", 1,
+			   &fs_info->generic_worker);
 	btrfs_init_workers(&fs_info->endio_workers, "endio",
-			   fs_info->thread_pool_size);
+			   fs_info->thread_pool_size,
+			   &fs_info->generic_worker);
 	btrfs_init_workers(&fs_info->endio_meta_workers, "endio-meta",
-			   fs_info->thread_pool_size);
+			   fs_info->thread_pool_size,
+			   &fs_info->generic_worker);
 	btrfs_init_workers(&fs_info->endio_meta_write_workers,
-			   "endio-meta-write", fs_info->thread_pool_size);
+			   "endio-meta-write", fs_info->thread_pool_size,
+			   &fs_info->generic_worker);
 	btrfs_init_workers(&fs_info->endio_write_workers, "endio-write",
-			   fs_info->thread_pool_size);
+			   fs_info->thread_pool_size,
+			   &fs_info->generic_worker);
 
 	/*
 	 * endios are largely parallel and should have a very
@@ -1745,20 +1802,19 @@ struct btrfs_root *open_ctree(struct super_block *sb,
 	fs_info->endio_workers.idle_thresh = 4;
 	fs_info->endio_meta_workers.idle_thresh = 4;
 
-	fs_info->endio_write_workers.idle_thresh = 64;
-	fs_info->endio_meta_write_workers.idle_thresh = 64;
+	fs_info->endio_write_workers.idle_thresh = 2;
+	fs_info->endio_meta_write_workers.idle_thresh = 2;
 
 	btrfs_start_workers(&fs_info->workers, 1);
+	btrfs_start_workers(&fs_info->generic_worker, 1);
 	btrfs_start_workers(&fs_info->submit_workers, 1);
 	btrfs_start_workers(&fs_info->delalloc_workers, 1);
 	btrfs_start_workers(&fs_info->fixup_workers, 1);
-	btrfs_start_workers(&fs_info->endio_workers, fs_info->thread_pool_size);
-	btrfs_start_workers(&fs_info->endio_meta_workers,
-			    fs_info->thread_pool_size);
-	btrfs_start_workers(&fs_info->endio_meta_write_workers,
-			    fs_info->thread_pool_size);
-	btrfs_start_workers(&fs_info->endio_write_workers,
-			    fs_info->thread_pool_size);
+	btrfs_start_workers(&fs_info->endio_workers, 1);
+	btrfs_start_workers(&fs_info->endio_meta_workers, 1);
+	btrfs_start_workers(&fs_info->endio_meta_write_workers, 1);
+	btrfs_start_workers(&fs_info->endio_write_workers, 1);
+	btrfs_start_workers(&fs_info->enospc_workers, 1);
 
 	fs_info->bdi.ra_pages *= btrfs_super_num_devices(disk_super);
 	fs_info->bdi.ra_pages = max(fs_info->bdi.ra_pages,
@@ -1918,6 +1974,9 @@ struct btrfs_root *open_ctree(struct super_block *sb,
 		}
 	}
 
+	ret = btrfs_find_orphan_roots(tree_root);
+	BUG_ON(ret);
+
 	if (!(sb->s_flags & MS_RDONLY)) {
 		ret = btrfs_recover_relocation(tree_root);
 		BUG_ON(ret);
@@ -1961,6 +2020,7 @@ fail_chunk_root:
 	free_extent_buffer(chunk_root->node);
 	free_extent_buffer(chunk_root->commit_root);
 fail_sb_buffer:
+	btrfs_stop_workers(&fs_info->generic_worker);
 	btrfs_stop_workers(&fs_info->fixup_workers);
 	btrfs_stop_workers(&fs_info->delalloc_workers);
 	btrfs_stop_workers(&fs_info->workers);
@@ -1969,6 +2029,7 @@ fail_sb_buffer:
 	btrfs_stop_workers(&fs_info->endio_meta_write_workers);
 	btrfs_stop_workers(&fs_info->endio_write_workers);
 	btrfs_stop_workers(&fs_info->submit_workers);
+	btrfs_stop_workers(&fs_info->enospc_workers);
 fail_iput:
 	invalidate_inode_pages2(fs_info->btree_inode->i_mapping);
 	iput(fs_info->btree_inode);
@@ -1977,6 +2038,8 @@ fail_iput:
 	btrfs_mapping_tree_free(&fs_info->mapping_tree);
 fail_bdi:
 	bdi_destroy(&fs_info->bdi);
+fail_srcu:
+	cleanup_srcu_struct(&fs_info->subvol_srcu);
 fail:
 	kfree(extent_root);
 	kfree(tree_root);
@@ -2236,20 +2299,29 @@ int write_ctree_super(struct btrfs_trans_handle *trans,
 
 int btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
 {
-	WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
+	spin_lock(&fs_info->fs_roots_radix_lock);
 	radix_tree_delete(&fs_info->fs_roots_radix,
 			  (unsigned long)root->root_key.objectid);
+	spin_unlock(&fs_info->fs_roots_radix_lock);
+
+	if (btrfs_root_refs(&root->root_item) == 0)
+		synchronize_srcu(&fs_info->subvol_srcu);
+
+	free_fs_root(root);
+	return 0;
+}
+
+static void free_fs_root(struct btrfs_root *root)
+{
+	WARN_ON(!RB_EMPTY_ROOT(&root->inode_tree));
 	if (root->anon_super.s_dev) {
 		down_write(&root->anon_super.s_umount);
 		kill_anon_super(&root->anon_super);
 	}
-	if (root->node)
-		free_extent_buffer(root->node);
-	if (root->commit_root)
-		free_extent_buffer(root->commit_root);
+	free_extent_buffer(root->node);
+	free_extent_buffer(root->commit_root);
 	kfree(root->name);
 	kfree(root);
-	return 0;
 }
 
 static int del_fs_roots(struct btrfs_fs_info *fs_info)
@@ -2258,6 +2330,20 @@ static int del_fs_roots(struct btrfs_fs_info *fs_info)
 	struct btrfs_root *gang[8];
 	int i;
 
+	while (!list_empty(&fs_info->dead_roots)) {
+		gang[0] = list_entry(fs_info->dead_roots.next,
+				     struct btrfs_root, root_list);
+		list_del(&gang[0]->root_list);
+
+		if (gang[0]->in_radix) {
+			btrfs_free_fs_root(fs_info, gang[0]);
+		} else {
+			free_extent_buffer(gang[0]->node);
+			free_extent_buffer(gang[0]->commit_root);
+			kfree(gang[0]);
+		}
+	}
+
 	while (1) {
 		ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
 					     (void **)gang, 0,
@@ -2287,9 +2373,6 @@ int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
 		root_objectid = gang[ret - 1]->root_key.objectid + 1;
 		for (i = 0; i < ret; i++) {
 			root_objectid = gang[i]->root_key.objectid;
-			ret = btrfs_find_dead_roots(fs_info->tree_root,
-						    root_objectid);
-			BUG_ON(ret);
 			btrfs_orphan_cleanup(gang[i]);
 		}
 		root_objectid++;
@@ -2359,12 +2442,12 @@ int close_ctree(struct btrfs_root *root)
 	free_extent_buffer(root->fs_info->csum_root->commit_root);
 
 	btrfs_free_block_groups(root->fs_info);
-	btrfs_free_pinned_extents(root->fs_info);
 
 	del_fs_roots(fs_info);
 
 	iput(fs_info->btree_inode);
 
+	btrfs_stop_workers(&fs_info->generic_worker);
 	btrfs_stop_workers(&fs_info->fixup_workers);
 	btrfs_stop_workers(&fs_info->delalloc_workers);
 	btrfs_stop_workers(&fs_info->workers);
@@ -2373,11 +2456,13 @@ int close_ctree(struct btrfs_root *root)
 	btrfs_stop_workers(&fs_info->endio_meta_write_workers);
 	btrfs_stop_workers(&fs_info->endio_write_workers);
 	btrfs_stop_workers(&fs_info->submit_workers);
+	btrfs_stop_workers(&fs_info->enospc_workers);
 
 	btrfs_close_devices(fs_info->fs_devices);
 	btrfs_mapping_tree_free(&fs_info->mapping_tree);
 
 	bdi_destroy(&fs_info->bdi);
+	cleanup_srcu_struct(&fs_info->subvol_srcu);
 
 	kfree(fs_info->extent_root);
 	kfree(fs_info->tree_root);
diff --git a/fs/btrfs/export.c b/fs/btrfs/export.c
index 9596b40..ba5c3fd 100644
--- a/fs/btrfs/export.c
+++ b/fs/btrfs/export.c
@@ -28,7 +28,7 @@ static int btrfs_encode_fh(struct dentry *dentry, u32 *fh, int *max_len,
 	len  = BTRFS_FID_SIZE_NON_CONNECTABLE;
 	type = FILEID_BTRFS_WITHOUT_PARENT;
 
-	fid->objectid = BTRFS_I(inode)->location.objectid;
+	fid->objectid = inode->i_ino;
 	fid->root_objectid = BTRFS_I(inode)->root->objectid;
 	fid->gen = inode->i_generation;
 
@@ -60,34 +60,61 @@ static int btrfs_encode_fh(struct dentry *dentry, u32 *fh, int *max_len,
 }
 
 static struct dentry *btrfs_get_dentry(struct super_block *sb, u64 objectid,
-				       u64 root_objectid, u32 generation)
+				       u64 root_objectid, u32 generation,
+				       int check_generation)
 {
+	struct btrfs_fs_info *fs_info = btrfs_sb(sb)->fs_info;
 	struct btrfs_root *root;
+	struct dentry *dentry;
 	struct inode *inode;
 	struct btrfs_key key;
+	int index;
+	int err = 0;
+
+	if (objectid < BTRFS_FIRST_FREE_OBJECTID)
+		return ERR_PTR(-ESTALE);
 
 	key.objectid = root_objectid;
 	btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
 	key.offset = (u64)-1;
 
-	root = btrfs_read_fs_root_no_name(btrfs_sb(sb)->fs_info, &key);
-	if (IS_ERR(root))
-		return ERR_CAST(root);
+	index = srcu_read_lock(&fs_info->subvol_srcu);
+
+	root = btrfs_read_fs_root_no_name(fs_info, &key);
+	if (IS_ERR(root)) {
+		err = PTR_ERR(root);
+		goto fail;
+	}
+
+	if (btrfs_root_refs(&root->root_item) == 0) {
+		err = -ENOENT;
+		goto fail;
+	}
 
 	key.objectid = objectid;
 	btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
 	key.offset = 0;
 
 	inode = btrfs_iget(sb, &key, root);
-	if (IS_ERR(inode))
-		return (void *)inode;
+	if (IS_ERR(inode)) {
+		err = PTR_ERR(inode);
+		goto fail;
+	}
+
+	srcu_read_unlock(&fs_info->subvol_srcu, index);
 
-	if (generation != inode->i_generation) {
+	if (check_generation && generation != inode->i_generation) {
 		iput(inode);
 		return ERR_PTR(-ESTALE);
 	}
 
-	return d_obtain_alias(inode);
+	dentry = d_obtain_alias(inode);
+	if (!IS_ERR(dentry))
+		dentry->d_op = &btrfs_dentry_operations;
+	return dentry;
+fail:
+	srcu_read_unlock(&fs_info->subvol_srcu, index);
+	return ERR_PTR(err);
 }
 
 static struct dentry *btrfs_fh_to_parent(struct super_block *sb, struct fid *fh,
@@ -111,7 +138,7 @@ static struct dentry *btrfs_fh_to_parent(struct super_block *sb, struct fid *fh,
 	objectid = fid->parent_objectid;
 	generation = fid->parent_gen;
 
-	return btrfs_get_dentry(sb, objectid, root_objectid, generation);
+	return btrfs_get_dentry(sb, objectid, root_objectid, generation, 1);
 }
 
 static struct dentry *btrfs_fh_to_dentry(struct super_block *sb, struct fid *fh,
@@ -133,66 +160,76 @@ static struct dentry *btrfs_fh_to_dentry(struct super_block *sb, struct fid *fh,
 	root_objectid = fid->root_objectid;
 	generation = fid->gen;
 
-	return btrfs_get_dentry(sb, objectid, root_objectid, generation);
+	return btrfs_get_dentry(sb, objectid, root_objectid, generation, 1);
 }
 
 static struct dentry *btrfs_get_parent(struct dentry *child)
 {
 	struct inode *dir = child->d_inode;
+	static struct dentry *dentry;
 	struct btrfs_root *root = BTRFS_I(dir)->root;
-	struct btrfs_key key;
 	struct btrfs_path *path;
 	struct extent_buffer *leaf;
-	int slot;
-	u64 objectid;
+	struct btrfs_root_ref *ref;
+	struct btrfs_key key;
+	struct btrfs_key found_key;
 	int ret;
 
 	path = btrfs_alloc_path();
 
-	key.objectid = dir->i_ino;
-	btrfs_set_key_type(&key, BTRFS_INODE_REF_KEY);
-	key.offset = (u64)-1;
+	if (dir->i_ino == BTRFS_FIRST_FREE_OBJECTID) {
+		key.objectid = root->root_key.objectid;
+		key.type = BTRFS_ROOT_BACKREF_KEY;
+		key.offset = (u64)-1;
+		root = root->fs_info->tree_root;
+	} else {
+		key.objectid = dir->i_ino;
+		key.type = BTRFS_INODE_REF_KEY;
+		key.offset = (u64)-1;
+	}
 
 	ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
-	if (ret < 0) {
-		/* Error */
-		btrfs_free_path(path);
-		return ERR_PTR(ret);
+	if (ret < 0)
+		goto fail;
+
+	BUG_ON(ret == 0);
+	if (path->slots[0] == 0) {
+		ret = -ENOENT;
+		goto fail;
 	}
+
+	path->slots[0]--;
 	leaf = path->nodes[0];
-	slot = path->slots[0];
-	if (ret) {
-		/* btrfs_search_slot() returns the slot where we'd want to
-		   insert a backref for parent inode #0xFFFFFFFFFFFFFFFF.
-		   The _real_ backref, telling us what the parent inode
-		   _actually_ is, will be in the slot _before_ the one
-		   that btrfs_search_slot() returns. */
-		if (!slot) {
-			/* Unless there is _no_ key in the tree before... */
-			btrfs_free_path(path);
-			return ERR_PTR(-EIO);
-		}
-		slot--;
+
+	btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
+	if (found_key.objectid != key.objectid || found_key.type != key.type) {
+		ret = -ENOENT;
+		goto fail;
 	}
 
-	btrfs_item_key_to_cpu(leaf, &key, slot);
+	if (found_key.type == BTRFS_ROOT_BACKREF_KEY) {
+		ref = btrfs_item_ptr(leaf, path->slots[0],
+				     struct btrfs_root_ref);
+		key.objectid = btrfs_root_ref_dirid(leaf, ref);
+	} else {
+		key.objectid = found_key.offset;
+	}
 	btrfs_free_path(path);
 
-	if (key.objectid != dir->i_ino || key.type != BTRFS_INODE_REF_KEY)
-		return ERR_PTR(-EINVAL);
-
-	objectid = key.offset;
-
-	/* If we are already at the root of a subvol, return the real root */
-	if (objectid == dir->i_ino)
-		return dget(dir->i_sb->s_root);
+	if (found_key.type == BTRFS_ROOT_BACKREF_KEY) {
+		return btrfs_get_dentry(root->fs_info->sb, key.objectid,
+					found_key.offset, 0, 0);
+	}
 
-	/* Build a new key for the inode item */
-	key.objectid = objectid;
-	btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
+	key.type = BTRFS_INODE_ITEM_KEY;
 	key.offset = 0;
-
-	return d_obtain_alias(btrfs_iget(root->fs_info->sb, &key, root));
+	dentry = d_obtain_alias(btrfs_iget(root->fs_info->sb, &key, root));
+	if (!IS_ERR(dentry))
+		dentry->d_op = &btrfs_dentry_operations;
+	return dentry;
+fail:
+	btrfs_free_path(path);
+	return ERR_PTR(ret);
 }
 
 const struct export_operations btrfs_export_ops = {
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 535f85b..e238a0c 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -32,12 +32,12 @@
 #include "locking.h"
 #include "free-space-cache.h"
 
-static int update_reserved_extents(struct btrfs_root *root,
-				   u64 bytenr, u64 num, int reserve);
 static int update_block_group(struct btrfs_trans_handle *trans,
 			      struct btrfs_root *root,
 			      u64 bytenr, u64 num_bytes, int alloc,
 			      int mark_free);
+static int update_reserved_extents(struct btrfs_block_group_cache *cache,
+				   u64 num_bytes, int reserve);
 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
 				struct btrfs_root *root,
 				u64 bytenr, u64 num_bytes, u64 parent,
@@ -57,10 +57,19 @@ static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
 				     u64 parent, u64 root_objectid,
 				     u64 flags, struct btrfs_disk_key *key,
 				     int level, struct btrfs_key *ins);
-
 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
 			  struct btrfs_root *extent_root, u64 alloc_bytes,
 			  u64 flags, int force);
+static int pin_down_bytes(struct btrfs_trans_handle *trans,
+			  struct btrfs_root *root,
+			  struct btrfs_path *path,
+			  u64 bytenr, u64 num_bytes,
+			  int is_data, int reserved,
+			  struct extent_buffer **must_clean);
+static int find_next_key(struct btrfs_path *path, int level,
+			 struct btrfs_key *key);
+static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
+			    int dump_block_groups);
 
 static noinline int
 block_group_cache_done(struct btrfs_block_group_cache *cache)
@@ -153,34 +162,34 @@ block_group_cache_tree_search(struct btrfs_fs_info *info, u64 bytenr,
 	return ret;
 }
 
-/*
- * We always set EXTENT_LOCKED for the super mirror extents so we don't
- * overwrite them, so those bits need to be unset.  Also, if we are unmounting
- * with pinned extents still sitting there because we had a block group caching,
- * we need to clear those now, since we are done.
- */
-void btrfs_free_pinned_extents(struct btrfs_fs_info *info)
+static int add_excluded_extent(struct btrfs_root *root,
+			       u64 start, u64 num_bytes)
 {
-	u64 start, end, last = 0;
-	int ret;
+	u64 end = start + num_bytes - 1;
+	set_extent_bits(&root->fs_info->freed_extents[0],
+			start, end, EXTENT_UPTODATE, GFP_NOFS);
+	set_extent_bits(&root->fs_info->freed_extents[1],
+			start, end, EXTENT_UPTODATE, GFP_NOFS);
+	return 0;
+}
 
-	while (1) {
-		ret = find_first_extent_bit(&info->pinned_extents, last,
-					    &start, &end,
-					    EXTENT_LOCKED|EXTENT_DIRTY);
-		if (ret)
-			break;
+static void free_excluded_extents(struct btrfs_root *root,
+				  struct btrfs_block_group_cache *cache)
+{
+	u64 start, end;
 
-		clear_extent_bits(&info->pinned_extents, start, end,
-				  EXTENT_LOCKED|EXTENT_DIRTY, GFP_NOFS);
-		last = end+1;
-	}
+	start = cache->key.objectid;
+	end = start + cache->key.offset - 1;
+
+	clear_extent_bits(&root->fs_info->freed_extents[0],
+			  start, end, EXTENT_UPTODATE, GFP_NOFS);
+	clear_extent_bits(&root->fs_info->freed_extents[1],
+			  start, end, EXTENT_UPTODATE, GFP_NOFS);
 }
 
-static int remove_sb_from_cache(struct btrfs_root *root,
-				struct btrfs_block_group_cache *cache)
+static int exclude_super_stripes(struct btrfs_root *root,
+				 struct btrfs_block_group_cache *cache)
 {
-	struct btrfs_fs_info *fs_info = root->fs_info;
 	u64 bytenr;
 	u64 *logical;
 	int stripe_len;
@@ -192,17 +201,42 @@ static int remove_sb_from_cache(struct btrfs_root *root,
 				       cache->key.objectid, bytenr,
 				       0, &logical, &nr, &stripe_len);
 		BUG_ON(ret);
+
 		while (nr--) {
-			try_lock_extent(&fs_info->pinned_extents,
-					logical[nr],
-					logical[nr] + stripe_len - 1, GFP_NOFS);
+			cache->bytes_super += stripe_len;
+			ret = add_excluded_extent(root, logical[nr],
+						  stripe_len);
+			BUG_ON(ret);
 		}
+
 		kfree(logical);
 	}
-
 	return 0;
 }
 
+static struct btrfs_caching_control *
+get_caching_control(struct btrfs_block_group_cache *cache)
+{
+	struct btrfs_caching_control *ctl;
+
+	spin_lock(&cache->lock);
+	if (cache->cached != BTRFS_CACHE_STARTED) {
+		spin_unlock(&cache->lock);
+		return NULL;
+	}
+
+	ctl = cache->caching_ctl;
+	atomic_inc(&ctl->count);
+	spin_unlock(&cache->lock);
+	return ctl;
+}
+
+static void put_caching_control(struct btrfs_caching_control *ctl)
+{
+	if (atomic_dec_and_test(&ctl->count))
+		kfree(ctl);
+}
+
 /*
  * this is only called by cache_block_group, since we could have freed extents
  * we need to check the pinned_extents for any extents that can't be used yet
@@ -215,9 +249,9 @@ static u64 add_new_free_space(struct btrfs_block_group_cache *block_group,
 	int ret;
 
 	while (start < end) {
-		ret = find_first_extent_bit(&info->pinned_extents, start,
+		ret = find_first_extent_bit(info->pinned_extents, start,
 					    &extent_start, &extent_end,
-					    EXTENT_DIRTY|EXTENT_LOCKED);
+					    EXTENT_DIRTY | EXTENT_UPTODATE);
 		if (ret)
 			break;
 
@@ -249,22 +283,27 @@ static int caching_kthread(void *data)
 {
 	struct btrfs_block_group_cache *block_group = data;
 	struct btrfs_fs_info *fs_info = block_group->fs_info;
-	u64 last = 0;
+	struct btrfs_caching_control *caching_ctl = block_group->caching_ctl;
+	struct btrfs_root *extent_root = fs_info->extent_root;
 	struct btrfs_path *path;
-	int ret = 0;
-	struct btrfs_key key;
 	struct extent_buffer *leaf;
-	int slot;
+	struct btrfs_key key;
 	u64 total_found = 0;
-
-	BUG_ON(!fs_info);
+	u64 last = 0;
+	u32 nritems;
+	int ret = 0;
 
 	path = btrfs_alloc_path();
 	if (!path)
 		return -ENOMEM;
 
-	atomic_inc(&block_group->space_info->caching_threads);
+	exclude_super_stripes(extent_root, block_group);
+	spin_lock(&block_group->space_info->lock);
+	block_group->space_info->bytes_super += block_group->bytes_super;
+	spin_unlock(&block_group->space_info->lock);
+
 	last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
+
 	/*
 	 * We don't want to deadlock with somebody trying to allocate a new
 	 * extent for the extent root while also trying to search the extent
@@ -277,74 +316,64 @@ static int caching_kthread(void *data)
 
 	key.objectid = last;
 	key.offset = 0;
-	btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
+	key.type = BTRFS_EXTENT_ITEM_KEY;
 again:
+	mutex_lock(&caching_ctl->mutex);
 	/* need to make sure the commit_root doesn't disappear */
 	down_read(&fs_info->extent_commit_sem);
 
-	ret = btrfs_search_slot(NULL, fs_info->extent_root, &key, path, 0, 0);
+	ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
 	if (ret < 0)
 		goto err;
 
+	leaf = path->nodes[0];
+	nritems = btrfs_header_nritems(leaf);
+
 	while (1) {
 		smp_mb();
-		if (block_group->fs_info->closing > 1) {
+		if (fs_info->closing > 1) {
 			last = (u64)-1;
 			break;
 		}
 
-		leaf = path->nodes[0];
-		slot = path->slots[0];
-		if (slot >= btrfs_header_nritems(leaf)) {
-			ret = btrfs_next_leaf(fs_info->extent_root, path);
-			if (ret < 0)
-				goto err;
-			else if (ret)
+		if (path->slots[0] < nritems) {
+			btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
+		} else {
+			ret = find_next_key(path, 0, &key);
+			if (ret)
 				break;
 
-			if (need_resched() ||
-			    btrfs_transaction_in_commit(fs_info)) {
-				leaf = path->nodes[0];
-
-				/* this shouldn't happen, but if the
-				 * leaf is empty just move on.
-				 */
-				if (btrfs_header_nritems(leaf) == 0)
-					break;
-				/*
-				 * we need to copy the key out so that
-				 * we are sure the next search advances
-				 * us forward in the btree.
-				 */
-				btrfs_item_key_to_cpu(leaf, &key, 0);
-				btrfs_release_path(fs_info->extent_root, path);
-				up_read(&fs_info->extent_commit_sem);
+			caching_ctl->progress = last;
+			btrfs_release_path(extent_root, path);
+			up_read(&fs_info->extent_commit_sem);
+			mutex_unlock(&caching_ctl->mutex);
+			if (btrfs_transaction_in_commit(fs_info))
 				schedule_timeout(1);
-				goto again;
-			}
+			else
+				cond_resched();
+			goto again;
+		}
 
+		if (key.objectid < block_group->key.objectid) {
+			path->slots[0]++;
 			continue;
 		}
-		btrfs_item_key_to_cpu(leaf, &key, slot);
-		if (key.objectid < block_group->key.objectid)
-			goto next;
 
 		if (key.objectid >= block_group->key.objectid +
 		    block_group->key.offset)
 			break;
 
-		if (btrfs_key_type(&key) == BTRFS_EXTENT_ITEM_KEY) {
+		if (key.type == BTRFS_EXTENT_ITEM_KEY) {
 			total_found += add_new_free_space(block_group,
 							  fs_info, last,
 							  key.objectid);
 			last = key.objectid + key.offset;
-		}
 
-		if (total_found > (1024 * 1024 * 2)) {
-			total_found = 0;
-			wake_up(&block_group->caching_q);
+			if (total_found > (1024 * 1024 * 2)) {
+				total_found = 0;
+				wake_up(&caching_ctl->wait);
+			}
 		}
-next:
 		path->slots[0]++;
 	}
 	ret = 0;
@@ -352,33 +381,65 @@ next:
 	total_found += add_new_free_space(block_group, fs_info, last,
 					  block_group->key.objectid +
 					  block_group->key.offset);
+	caching_ctl->progress = (u64)-1;
 
 	spin_lock(&block_group->lock);
+	block_group->caching_ctl = NULL;
 	block_group->cached = BTRFS_CACHE_FINISHED;
 	spin_unlock(&block_group->lock);
 
 err:
 	btrfs_free_path(path);
 	up_read(&fs_info->extent_commit_sem);
-	atomic_dec(&block_group->space_info->caching_threads);
-	wake_up(&block_group->caching_q);
 
+	free_excluded_extents(extent_root, block_group);
+
+	mutex_unlock(&caching_ctl->mutex);
+	wake_up(&caching_ctl->wait);
+
+	put_caching_control(caching_ctl);
+	atomic_dec(&block_group->space_info->caching_threads);
 	return 0;
 }
 
 static int cache_block_group(struct btrfs_block_group_cache *cache)
 {
+	struct btrfs_fs_info *fs_info = cache->fs_info;
+	struct btrfs_caching_control *caching_ctl;
 	struct task_struct *tsk;
 	int ret = 0;
 
+	smp_mb();
+	if (cache->cached != BTRFS_CACHE_NO)
+		return 0;
+
+	caching_ctl = kzalloc(sizeof(*caching_ctl), GFP_KERNEL);
+	BUG_ON(!caching_ctl);
+
+	INIT_LIST_HEAD(&caching_ctl->list);
+	mutex_init(&caching_ctl->mutex);
+	init_waitqueue_head(&caching_ctl->wait);
+	caching_ctl->block_group = cache;
+	caching_ctl->progress = cache->key.objectid;
+	/* one for caching kthread, one for caching block group list */
+	atomic_set(&caching_ctl->count, 2);
+
 	spin_lock(&cache->lock);
 	if (cache->cached != BTRFS_CACHE_NO) {
 		spin_unlock(&cache->lock);
-		return ret;
+		kfree(caching_ctl);
+		return 0;
 	}
+	cache->caching_ctl = caching_ctl;
 	cache->cached = BTRFS_CACHE_STARTED;
 	spin_unlock(&cache->lock);
 
+	down_write(&fs_info->extent_commit_sem);
+	list_add_tail(&caching_ctl->list, &fs_info->caching_block_groups);
+	up_write(&fs_info->extent_commit_sem);
+
+	atomic_inc(&cache->space_info->caching_threads);
+
 	tsk = kthread_run(caching_kthread, cache, "btrfs-cache-%llu\n",
 			  cache->key.objectid);
 	if (IS_ERR(tsk)) {
@@ -1507,23 +1568,23 @@ static int remove_extent_backref(struct btrfs_trans_handle *trans,
 	return ret;
 }
 
-#ifdef BIO_RW_DISCARD
 static void btrfs_issue_discard(struct block_device *bdev,
 				u64 start, u64 len)
 {
 	blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_KERNEL,
 			     DISCARD_FL_BARRIER);
 }
-#endif
 
 static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
 				u64 num_bytes)
 {
-#ifdef BIO_RW_DISCARD
 	int ret;
 	u64 map_length = num_bytes;
 	struct btrfs_multi_bio *multi = NULL;
 
+	if (!btrfs_test_opt(root, DISCARD))
+		return 0;
+
 	/* Tell the block device(s) that the sectors can be discarded */
 	ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
 			      bytenr, &map_length, &multi, 0);
@@ -1543,9 +1604,6 @@ static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
 	}
 
 	return ret;
-#else
-	return 0;
-#endif
 }
 
 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
@@ -1657,7 +1715,6 @@ static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
 						 parent, ref_root, flags,
 						 ref->objectid, ref->offset,
 						 &ins, node->ref_mod);
-		update_reserved_extents(root, ins.objectid, ins.offset, 0);
 	} else if (node->action == BTRFS_ADD_DELAYED_REF) {
 		ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
 					     node->num_bytes, parent,
@@ -1783,7 +1840,6 @@ static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
 						extent_op->flags_to_set,
 						&extent_op->key,
 						ref->level, &ins);
-		update_reserved_extents(root, ins.objectid, ins.offset, 0);
 	} else if (node->action == BTRFS_ADD_DELAYED_REF) {
 		ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
 					     node->num_bytes, parent, ref_root,
@@ -1818,16 +1874,32 @@ static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
 		BUG_ON(extent_op);
 		head = btrfs_delayed_node_to_head(node);
 		if (insert_reserved) {
+			int mark_free = 0;
+			struct extent_buffer *must_clean = NULL;
+
+			ret = pin_down_bytes(trans, root, NULL,
+					     node->bytenr, node->num_bytes,
+					     head->is_data, 1, &must_clean);
+			if (ret > 0)
+				mark_free = 1;
+
+			if (must_clean) {
+				clean_tree_block(NULL, root, must_clean);
+				btrfs_tree_unlock(must_clean);
+				free_extent_buffer(must_clean);
+			}
 			if (head->is_data) {
 				ret = btrfs_del_csums(trans, root,
 						      node->bytenr,
 						      node->num_bytes);
 				BUG_ON(ret);
 			}
-			btrfs_update_pinned_extents(root, node->bytenr,
-						    node->num_bytes, 1);
-			update_reserved_extents(root, node->bytenr,
-						node->num_bytes, 0);
+			if (mark_free) {
+				ret = btrfs_free_reserved_extent(root,
+							node->bytenr,
+							node->num_bytes);
+				BUG_ON(ret);
+			}
 		}
 		mutex_unlock(&head->mutex);
 		return 0;
@@ -2692,60 +2764,448 @@ void btrfs_set_inode_space_info(struct btrfs_root *root, struct inode *inode)
 						       alloc_target);
 }
 
+static u64 calculate_bytes_needed(struct btrfs_root *root, int num_items)
+{
+	u64 num_bytes;
+	int level;
+
+	level = BTRFS_MAX_LEVEL - 2;
+	/*
+	 * NOTE: these calculations are absolutely the worst possible case.
+	 * This assumes that _every_ item we insert will require a new leaf, and
+	 * that the tree has grown to its maximum level size.
+	 */
+
+	/*
+	 * for every item we insert we could insert both an extent item and a
+	 * extent ref item.  Then for ever item we insert, we will need to cow
+	 * both the original leaf, plus the leaf to the left and right of it.
+	 *
+	 * Unless we are talking about the extent root, then we just want the
+	 * number of items * 2, since we just need the extent item plus its ref.
+	 */
+	if (root == root->fs_info->extent_root)
+		num_bytes = num_items * 2;
+	else
+		num_bytes = (num_items + (2 * num_items)) * 3;
+
+	/*
+	 * num_bytes is total number of leaves we could need times the leaf
+	 * size, and then for every leaf we could end up cow'ing 2 nodes per
+	 * level, down to the leaf level.
+	 */
+	num_bytes = (num_bytes * root->leafsize) +
+		(num_bytes * (level * 2)) * root->nodesize;
+
+	return num_bytes;
+}
+
 /*
- * for now this just makes sure we have at least 5% of our metadata space free
- * for use.
+ * Unreserve metadata space for delalloc.  If we have less reserved credits than
+ * we have extents, this function does nothing.
  */
-int btrfs_check_metadata_free_space(struct btrfs_root *root)
+int btrfs_unreserve_metadata_for_delalloc(struct btrfs_root *root,
+					  struct inode *inode, int num_items)
 {
 	struct btrfs_fs_info *info = root->fs_info;
 	struct btrfs_space_info *meta_sinfo;
-	u64 alloc_target, thresh;
-	int committed = 0, ret;
+	u64 num_bytes;
+	u64 alloc_target;
+	bool bug = false;
 
 	/* get the space info for where the metadata will live */
 	alloc_target = btrfs_get_alloc_profile(root, 0);
 	meta_sinfo = __find_space_info(info, alloc_target);
 
-again:
+	num_bytes = calculate_bytes_needed(root->fs_info->extent_root,
+					   num_items);
+
 	spin_lock(&meta_sinfo->lock);
-	if (!meta_sinfo->full)
-		thresh = meta_sinfo->total_bytes * 80;
-	else
-		thresh = meta_sinfo->total_bytes * 95;
+	spin_lock(&BTRFS_I(inode)->accounting_lock);
+	if (BTRFS_I(inode)->reserved_extents <=
+	    BTRFS_I(inode)->outstanding_extents) {
+		spin_unlock(&BTRFS_I(inode)->accounting_lock);
+		spin_unlock(&meta_sinfo->lock);
+		return 0;
+	}
+	spin_unlock(&BTRFS_I(inode)->accounting_lock);
+
+	BTRFS_I(inode)->reserved_extents--;
+	BUG_ON(BTRFS_I(inode)->reserved_extents < 0);
+
+	if (meta_sinfo->bytes_delalloc < num_bytes) {
+		bug = true;
+		meta_sinfo->bytes_delalloc = 0;
+	} else {
+		meta_sinfo->bytes_delalloc -= num_bytes;
+	}
+	spin_unlock(&meta_sinfo->lock);
+
+	BUG_ON(bug);
+
+	return 0;
+}
+
+static void check_force_delalloc(struct btrfs_space_info *meta_sinfo)
+{
+	u64 thresh;
+
+	thresh = meta_sinfo->bytes_used + meta_sinfo->bytes_reserved +
+		meta_sinfo->bytes_pinned + meta_sinfo->bytes_readonly +
+		meta_sinfo->bytes_super + meta_sinfo->bytes_root +
+		meta_sinfo->bytes_may_use;
 
+	thresh = meta_sinfo->total_bytes - thresh;
+	thresh *= 80;
 	do_div(thresh, 100);
+	if (thresh <= meta_sinfo->bytes_delalloc)
+		meta_sinfo->force_delalloc = 1;
+	else
+		meta_sinfo->force_delalloc = 0;
+}
 
-	if (meta_sinfo->bytes_used + meta_sinfo->bytes_reserved +
-	    meta_sinfo->bytes_pinned + meta_sinfo->bytes_readonly > thresh) {
-		struct btrfs_trans_handle *trans;
-		if (!meta_sinfo->full) {
-			meta_sinfo->force_alloc = 1;
-			spin_unlock(&meta_sinfo->lock);
+struct async_flush {
+	struct btrfs_root *root;
+	struct btrfs_space_info *info;
+	struct btrfs_work work;
+};
 
-			trans = btrfs_start_transaction(root, 1);
-			if (!trans)
-				return -ENOMEM;
+static noinline void flush_delalloc_async(struct btrfs_work *work)
+{
+	struct async_flush *async;
+	struct btrfs_root *root;
+	struct btrfs_space_info *info;
 
-			ret = do_chunk_alloc(trans, root->fs_info->extent_root,
-					     2 * 1024 * 1024, alloc_target, 0);
-			btrfs_end_transaction(trans, root);
+	async = container_of(work, struct async_flush, work);
+	root = async->root;
+	info = async->info;
+
+	btrfs_start_delalloc_inodes(root);
+	wake_up(&info->flush_wait);
+	btrfs_wait_ordered_extents(root, 0);
+
+	spin_lock(&info->lock);
+	info->flushing = 0;
+	spin_unlock(&info->lock);
+	wake_up(&info->flush_wait);
+
+	kfree(async);
+}
+
+static void wait_on_flush(struct btrfs_space_info *info)
+{
+	DEFINE_WAIT(wait);
+	u64 used;
+
+	while (1) {
+		prepare_to_wait(&info->flush_wait, &wait,
+				TASK_UNINTERRUPTIBLE);
+		spin_lock(&info->lock);
+		if (!info->flushing) {
+			spin_unlock(&info->lock);
+			break;
+		}
+
+		used = info->bytes_used + info->bytes_reserved +
+			info->bytes_pinned + info->bytes_readonly +
+			info->bytes_super + info->bytes_root +
+			info->bytes_may_use + info->bytes_delalloc;
+		if (used < info->total_bytes) {
+			spin_unlock(&info->lock);
+			break;
+		}
+		spin_unlock(&info->lock);
+		schedule();
+	}
+	finish_wait(&info->flush_wait, &wait);
+}
+
+static void flush_delalloc(struct btrfs_root *root,
+				 struct btrfs_space_info *info)
+{
+	struct async_flush *async;
+	bool wait = false;
+
+	spin_lock(&info->lock);
+
+	if (!info->flushing) {
+		info->flushing = 1;
+		init_waitqueue_head(&info->flush_wait);
+	} else {
+		wait = true;
+	}
+
+	spin_unlock(&info->lock);
+
+	if (wait) {
+		wait_on_flush(info);
+		return;
+	}
+
+	async = kzalloc(sizeof(*async), GFP_NOFS);
+	if (!async)
+		goto flush;
+
+	async->root = root;
+	async->info = info;
+	async->work.func = flush_delalloc_async;
+
+	btrfs_queue_worker(&root->fs_info->enospc_workers,
+			   &async->work);
+	wait_on_flush(info);
+	return;
+
+flush:
+	btrfs_start_delalloc_inodes(root);
+	btrfs_wait_ordered_extents(root, 0);
+
+	spin_lock(&info->lock);
+	info->flushing = 0;
+	spin_unlock(&info->lock);
+	wake_up(&info->flush_wait);
+}
+
+static int maybe_allocate_chunk(struct btrfs_root *root,
+				 struct btrfs_space_info *info)
+{
+	struct btrfs_super_block *disk_super = &root->fs_info->super_copy;
+	struct btrfs_trans_handle *trans;
+	bool wait = false;
+	int ret = 0;
+	u64 min_metadata;
+	u64 free_space;
+
+	free_space = btrfs_super_total_bytes(disk_super);
+	/*
+	 * we allow the metadata to grow to a max of either 5gb or 5% of the
+	 * space in the volume.
+	 */
+	min_metadata = min((u64)5 * 1024 * 1024 * 1024,
+			     div64_u64(free_space * 5, 100));
+	if (info->total_bytes >= min_metadata) {
+		spin_unlock(&info->lock);
+		return 0;
+	}
+
+	if (info->full) {
+		spin_unlock(&info->lock);
+		return 0;
+	}
+
+	if (!info->allocating_chunk) {
+		info->force_alloc = 1;
+		info->allocating_chunk = 1;
+		init_waitqueue_head(&info->allocate_wait);
+	} else {
+		wait = true;
+	}
+
+	spin_unlock(&info->lock);
+
+	if (wait) {
+		wait_event(info->allocate_wait,
+			   !info->allocating_chunk);
+		return 1;
+	}
+
+	trans = btrfs_start_transaction(root, 1);
+	if (!trans) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	ret = do_chunk_alloc(trans, root->fs_info->extent_root,
+			     4096 + 2 * 1024 * 1024,
+			     info->flags, 0);
+	btrfs_end_transaction(trans, root);
+	if (ret)
+		goto out;
+out:
+	spin_lock(&info->lock);
+	info->allocating_chunk = 0;
+	spin_unlock(&info->lock);
+	wake_up(&info->allocate_wait);
+
+	if (ret)
+		return 0;
+	return 1;
+}
+
+/*
+ * Reserve metadata space for delalloc.
+ */
+int btrfs_reserve_metadata_for_delalloc(struct btrfs_root *root,
+					struct inode *inode, int num_items)
+{
+	struct btrfs_fs_info *info = root->fs_info;
+	struct btrfs_space_info *meta_sinfo;
+	u64 num_bytes;
+	u64 used;
+	u64 alloc_target;
+	int flushed = 0;
+	int force_delalloc;
+
+	/* get the space info for where the metadata will live */
+	alloc_target = btrfs_get_alloc_profile(root, 0);
+	meta_sinfo = __find_space_info(info, alloc_target);
+
+	num_bytes = calculate_bytes_needed(root->fs_info->extent_root,
+					   num_items);
+again:
+	spin_lock(&meta_sinfo->lock);
+
+	force_delalloc = meta_sinfo->force_delalloc;
+
+	if (unlikely(!meta_sinfo->bytes_root))
+		meta_sinfo->bytes_root = calculate_bytes_needed(root, 6);
+
+	if (!flushed)
+		meta_sinfo->bytes_delalloc += num_bytes;
+
+	used = meta_sinfo->bytes_used + meta_sinfo->bytes_reserved +
+		meta_sinfo->bytes_pinned + meta_sinfo->bytes_readonly +
+		meta_sinfo->bytes_super + meta_sinfo->bytes_root +
+		meta_sinfo->bytes_may_use + meta_sinfo->bytes_delalloc;
+
+	if (used > meta_sinfo->total_bytes) {
+		flushed++;
+
+		if (flushed == 1) {
+			if (maybe_allocate_chunk(root, meta_sinfo))
+				goto again;
+			flushed++;
+		} else {
+			spin_unlock(&meta_sinfo->lock);
+		}
+
+		if (flushed == 2) {
+			filemap_flush(inode->i_mapping);
+			goto again;
+		} else if (flushed == 3) {
+			flush_delalloc(root, meta_sinfo);
 			goto again;
 		}
+		spin_lock(&meta_sinfo->lock);
+		meta_sinfo->bytes_delalloc -= num_bytes;
 		spin_unlock(&meta_sinfo->lock);
+		printk(KERN_ERR "enospc, has %d, reserved %d\n",
+		       BTRFS_I(inode)->outstanding_extents,
+		       BTRFS_I(inode)->reserved_extents);
+		dump_space_info(meta_sinfo, 0, 0);
+		return -ENOSPC;
+	}
 
-		if (!committed) {
-			committed = 1;
-			trans = btrfs_join_transaction(root, 1);
-			if (!trans)
-				return -ENOMEM;
-			ret = btrfs_commit_transaction(trans, root);
-			if (ret)
-				return ret;
+	BTRFS_I(inode)->reserved_extents++;
+	check_force_delalloc(meta_sinfo);
+	spin_unlock(&meta_sinfo->lock);
+
+	if (!flushed && force_delalloc)
+		filemap_flush(inode->i_mapping);
+
+	return 0;
+}
+
+/*
+ * unreserve num_items number of items worth of metadata space.  This needs to
+ * be paired with btrfs_reserve_metadata_space.
+ *
+ * NOTE: if you have the option, run this _AFTER_ you do a
+ * btrfs_end_transaction, since btrfs_end_transaction will run delayed ref
+ * oprations which will result in more used metadata, so we want to make sure we
+ * can do that without issue.
+ */
+int btrfs_unreserve_metadata_space(struct btrfs_root *root, int num_items)
+{
+	struct btrfs_fs_info *info = root->fs_info;
+	struct btrfs_space_info *meta_sinfo;
+	u64 num_bytes;
+	u64 alloc_target;
+	bool bug = false;
+
+	/* get the space info for where the metadata will live */
+	alloc_target = btrfs_get_alloc_profile(root, 0);
+	meta_sinfo = __find_space_info(info, alloc_target);
+
+	num_bytes = calculate_bytes_needed(root, num_items);
+
+	spin_lock(&meta_sinfo->lock);
+	if (meta_sinfo->bytes_may_use < num_bytes) {
+		bug = true;
+		meta_sinfo->bytes_may_use = 0;
+	} else {
+		meta_sinfo->bytes_may_use -= num_bytes;
+	}
+	spin_unlock(&meta_sinfo->lock);
+
+	BUG_ON(bug);
+
+	return 0;
+}
+
+/*
+ * Reserve some metadata space for use.  We'll calculate the worste case number
+ * of bytes that would be needed to modify num_items number of items.  If we
+ * have space, fantastic, if not, you get -ENOSPC.  Please call
+ * btrfs_unreserve_metadata_space when you are done for the _SAME_ number of
+ * items you reserved, since whatever metadata you needed should have already
+ * been allocated.
+ *
+ * This will commit the transaction to make more space if we don't have enough
+ * metadata space.  THe only time we don't do this is if we're reserving space
+ * inside of a transaction, then we will just return -ENOSPC and it is the
+ * callers responsibility to handle it properly.
+ */
+int btrfs_reserve_metadata_space(struct btrfs_root *root, int num_items)
+{
+	struct btrfs_fs_info *info = root->fs_info;
+	struct btrfs_space_info *meta_sinfo;
+	u64 num_bytes;
+	u64 used;
+	u64 alloc_target;
+	int retries = 0;
+
+	/* get the space info for where the metadata will live */
+	alloc_target = btrfs_get_alloc_profile(root, 0);
+	meta_sinfo = __find_space_info(info, alloc_target);
+
+	num_bytes = calculate_bytes_needed(root, num_items);
+again:
+	spin_lock(&meta_sinfo->lock);
+
+	if (unlikely(!meta_sinfo->bytes_root))
+		meta_sinfo->bytes_root = calculate_bytes_needed(root, 6);
+
+	if (!retries)
+		meta_sinfo->bytes_may_use += num_bytes;
+
+	used = meta_sinfo->bytes_used + meta_sinfo->bytes_reserved +
+		meta_sinfo->bytes_pinned + meta_sinfo->bytes_readonly +
+		meta_sinfo->bytes_super + meta_sinfo->bytes_root +
+		meta_sinfo->bytes_may_use + meta_sinfo->bytes_delalloc;
+
+	if (used > meta_sinfo->total_bytes) {
+		retries++;
+		if (retries == 1) {
+			if (maybe_allocate_chunk(root, meta_sinfo))
+				goto again;
+			retries++;
+		} else {
+			spin_unlock(&meta_sinfo->lock);
+		}
+
+		if (retries == 2) {
+			flush_delalloc(root, meta_sinfo);
 			goto again;
 		}
+		spin_lock(&meta_sinfo->lock);
+		meta_sinfo->bytes_may_use -= num_bytes;
+		spin_unlock(&meta_sinfo->lock);
+
+		dump_space_info(meta_sinfo, 0, 0);
 		return -ENOSPC;
 	}
+
+	check_force_delalloc(meta_sinfo);
 	spin_unlock(&meta_sinfo->lock);
 
 	return 0;
@@ -2765,13 +3225,16 @@ int btrfs_check_data_free_space(struct btrfs_root *root, struct inode *inode,
 	bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
 
 	data_sinfo = BTRFS_I(inode)->space_info;
+	if (!data_sinfo)
+		goto alloc;
+
 again:
 	/* make sure we have enough space to handle the data first */
 	spin_lock(&data_sinfo->lock);
 	if (data_sinfo->total_bytes - data_sinfo->bytes_used -
 	    data_sinfo->bytes_delalloc - data_sinfo->bytes_reserved -
 	    data_sinfo->bytes_pinned - data_sinfo->bytes_readonly -
-	    data_sinfo->bytes_may_use < bytes) {
+	    data_sinfo->bytes_may_use - data_sinfo->bytes_super < bytes) {
 		struct btrfs_trans_handle *trans;
 
 		/*
@@ -2783,7 +3246,7 @@ again:
 
 			data_sinfo->force_alloc = 1;
 			spin_unlock(&data_sinfo->lock);
-
+alloc:
 			alloc_target = btrfs_get_alloc_profile(root, 1);
 			trans = btrfs_start_transaction(root, 1);
 			if (!trans)
@@ -2795,12 +3258,17 @@ again:
 			btrfs_end_transaction(trans, root);
 			if (ret)
 				return ret;
+
+			if (!data_sinfo) {
+				btrfs_set_inode_space_info(root, inode);
+				data_sinfo = BTRFS_I(inode)->space_info;
+			}
 			goto again;
 		}
 		spin_unlock(&data_sinfo->lock);
 
 		/* commit the current transaction and try again */
-		if (!committed) {
+		if (!committed && !root->fs_info->open_ioctl_trans) {
 			committed = 1;
 			trans = btrfs_join_transaction(root, 1);
 			if (!trans)
@@ -2828,7 +3296,7 @@ again:
 	BTRFS_I(inode)->reserved_bytes += bytes;
 	spin_unlock(&data_sinfo->lock);
 
-	return btrfs_check_metadata_free_space(root);
+	return 0;
 }
 
 /*
@@ -2927,17 +3395,15 @@ static int do_chunk_alloc(struct btrfs_trans_handle *trans,
 	BUG_ON(!space_info);
 
 	spin_lock(&space_info->lock);
-	if (space_info->force_alloc) {
+	if (space_info->force_alloc)
 		force = 1;
-		space_info->force_alloc = 0;
-	}
 	if (space_info->full) {
 		spin_unlock(&space_info->lock);
 		goto out;
 	}
 
 	thresh = space_info->total_bytes - space_info->bytes_readonly;
-	thresh = div_factor(thresh, 6);
+	thresh = div_factor(thresh, 8);
 	if (!force &&
 	   (space_info->bytes_used + space_info->bytes_pinned +
 	    space_info->bytes_reserved + alloc_bytes) < thresh) {
@@ -2951,7 +3417,7 @@ static int do_chunk_alloc(struct btrfs_trans_handle *trans,
 	 * we keep a reasonable number of metadata chunks allocated in the
 	 * FS as well.
 	 */
-	if (flags & BTRFS_BLOCK_GROUP_DATA) {
+	if (flags & BTRFS_BLOCK_GROUP_DATA && fs_info->metadata_ratio) {
 		fs_info->data_chunk_allocations++;
 		if (!(fs_info->data_chunk_allocations %
 		      fs_info->metadata_ratio))
@@ -2959,8 +3425,11 @@ static int do_chunk_alloc(struct btrfs_trans_handle *trans,
 	}
 
 	ret = btrfs_alloc_chunk(trans, extent_root, flags);
+	spin_lock(&space_info->lock);
 	if (ret)
 		space_info->full = 1;
+	space_info->force_alloc = 0;
+	spin_unlock(&space_info->lock);
 out:
 	mutex_unlock(&extent_root->fs_info->chunk_mutex);
 	return ret;
@@ -3009,10 +3478,12 @@ static int update_block_group(struct btrfs_trans_handle *trans,
 		num_bytes = min(total, cache->key.offset - byte_in_group);
 		if (alloc) {
 			old_val += num_bytes;
+			btrfs_set_block_group_used(&cache->item, old_val);
+			cache->reserved -= num_bytes;
 			cache->space_info->bytes_used += num_bytes;
+			cache->space_info->bytes_reserved -= num_bytes;
 			if (cache->ro)
 				cache->space_info->bytes_readonly -= num_bytes;
-			btrfs_set_block_group_used(&cache->item, old_val);
 			spin_unlock(&cache->lock);
 			spin_unlock(&cache->space_info->lock);
 		} else {
@@ -3057,127 +3528,136 @@ static u64 first_logical_byte(struct btrfs_root *root, u64 search_start)
 	return bytenr;
 }
 
-int btrfs_update_pinned_extents(struct btrfs_root *root,
-				u64 bytenr, u64 num, int pin)
+/*
+ * this function must be called within transaction
+ */
+int btrfs_pin_extent(struct btrfs_root *root,
+		     u64 bytenr, u64 num_bytes, int reserved)
 {
-	u64 len;
-	struct btrfs_block_group_cache *cache;
 	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct btrfs_block_group_cache *cache;
 
-	if (pin)
-		set_extent_dirty(&fs_info->pinned_extents,
-				bytenr, bytenr + num - 1, GFP_NOFS);
-
-	while (num > 0) {
-		cache = btrfs_lookup_block_group(fs_info, bytenr);
-		BUG_ON(!cache);
-		len = min(num, cache->key.offset -
-			  (bytenr - cache->key.objectid));
-		if (pin) {
-			spin_lock(&cache->space_info->lock);
-			spin_lock(&cache->lock);
-			cache->pinned += len;
-			cache->space_info->bytes_pinned += len;
-			spin_unlock(&cache->lock);
-			spin_unlock(&cache->space_info->lock);
-			fs_info->total_pinned += len;
-		} else {
-			int unpin = 0;
+	cache = btrfs_lookup_block_group(fs_info, bytenr);
+	BUG_ON(!cache);
 
-			/*
-			 * in order to not race with the block group caching, we
-			 * only want to unpin the extent if we are cached.  If
-			 * we aren't cached, we want to start async caching this
-			 * block group so we can free the extent the next time
-			 * around.
-			 */
-			spin_lock(&cache->space_info->lock);
-			spin_lock(&cache->lock);
-			unpin = (cache->cached == BTRFS_CACHE_FINISHED);
-			if (likely(unpin)) {
-				cache->pinned -= len;
-				cache->space_info->bytes_pinned -= len;
-				fs_info->total_pinned -= len;
-			}
-			spin_unlock(&cache->lock);
-			spin_unlock(&cache->space_info->lock);
+	spin_lock(&cache->space_info->lock);
+	spin_lock(&cache->lock);
+	cache->pinned += num_bytes;
+	cache->space_info->bytes_pinned += num_bytes;
+	if (reserved) {
+		cache->reserved -= num_bytes;
+		cache->space_info->bytes_reserved -= num_bytes;
+	}
+	spin_unlock(&cache->lock);
+	spin_unlock(&cache->space_info->lock);
 
-			if (likely(unpin))
-				clear_extent_dirty(&fs_info->pinned_extents,
-						   bytenr, bytenr + len -1,
-						   GFP_NOFS);
-			else
-				cache_block_group(cache);
+	btrfs_put_block_group(cache);
 
-			if (unpin)
-				btrfs_add_free_space(cache, bytenr, len);
-		}
-		btrfs_put_block_group(cache);
-		bytenr += len;
-		num -= len;
+	set_extent_dirty(fs_info->pinned_extents,
+			 bytenr, bytenr + num_bytes - 1, GFP_NOFS);
+	return 0;
+}
+
+static int update_reserved_extents(struct btrfs_block_group_cache *cache,
+				   u64 num_bytes, int reserve)
+{
+	spin_lock(&cache->space_info->lock);
+	spin_lock(&cache->lock);
+	if (reserve) {
+		cache->reserved += num_bytes;
+		cache->space_info->bytes_reserved += num_bytes;
+	} else {
+		cache->reserved -= num_bytes;
+		cache->space_info->bytes_reserved -= num_bytes;
 	}
+	spin_unlock(&cache->lock);
+	spin_unlock(&cache->space_info->lock);
 	return 0;
 }
 
-static int update_reserved_extents(struct btrfs_root *root,
-				   u64 bytenr, u64 num, int reserve)
+int btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,
+				struct btrfs_root *root)
 {
-	u64 len;
-	struct btrfs_block_group_cache *cache;
 	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct btrfs_caching_control *next;
+	struct btrfs_caching_control *caching_ctl;
+	struct btrfs_block_group_cache *cache;
 
-	while (num > 0) {
-		cache = btrfs_lookup_block_group(fs_info, bytenr);
-		BUG_ON(!cache);
-		len = min(num, cache->key.offset -
-			  (bytenr - cache->key.objectid));
+	down_write(&fs_info->extent_commit_sem);
 
-		spin_lock(&cache->space_info->lock);
-		spin_lock(&cache->lock);
-		if (reserve) {
-			cache->reserved += len;
-			cache->space_info->bytes_reserved += len;
+	list_for_each_entry_safe(caching_ctl, next,
+				 &fs_info->caching_block_groups, list) {
+		cache = caching_ctl->block_group;
+		if (block_group_cache_done(cache)) {
+			cache->last_byte_to_unpin = (u64)-1;
+			list_del_init(&caching_ctl->list);
+			put_caching_control(caching_ctl);
 		} else {
-			cache->reserved -= len;
-			cache->space_info->bytes_reserved -= len;
+			cache->last_byte_to_unpin = caching_ctl->progress;
 		}
-		spin_unlock(&cache->lock);
-		spin_unlock(&cache->space_info->lock);
-		btrfs_put_block_group(cache);
-		bytenr += len;
-		num -= len;
 	}
+
+	if (fs_info->pinned_extents == &fs_info->freed_extents[0])
+		fs_info->pinned_extents = &fs_info->freed_extents[1];
+	else
+		fs_info->pinned_extents = &fs_info->freed_extents[0];
+
+	up_write(&fs_info->extent_commit_sem);
 	return 0;
 }
 
-int btrfs_copy_pinned(struct btrfs_root *root, struct extent_io_tree *copy)
+static int unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
 {
-	u64 last = 0;
-	u64 start;
-	u64 end;
-	struct extent_io_tree *pinned_extents = &root->fs_info->pinned_extents;
-	int ret;
+	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct btrfs_block_group_cache *cache = NULL;
+	u64 len;
 
-	while (1) {
-		ret = find_first_extent_bit(pinned_extents, last,
-					    &start, &end, EXTENT_DIRTY);
-		if (ret)
-			break;
+	while (start <= end) {
+		if (!cache ||
+		    start >= cache->key.objectid + cache->key.offset) {
+			if (cache)
+				btrfs_put_block_group(cache);
+			cache = btrfs_lookup_block_group(fs_info, start);
+			BUG_ON(!cache);
+		}
 
-		set_extent_dirty(copy, start, end, GFP_NOFS);
-		last = end + 1;
+		len = cache->key.objectid + cache->key.offset - start;
+		len = min(len, end + 1 - start);
+
+		if (start < cache->last_byte_to_unpin) {
+			len = min(len, cache->last_byte_to_unpin - start);
+			btrfs_add_free_space(cache, start, len);
+		}
+
+		spin_lock(&cache->space_info->lock);
+		spin_lock(&cache->lock);
+		cache->pinned -= len;
+		cache->space_info->bytes_pinned -= len;
+		spin_unlock(&cache->lock);
+		spin_unlock(&cache->space_info->lock);
+
+		start += len;
 	}
+
+	if (cache)
+		btrfs_put_block_group(cache);
 	return 0;
 }
 
 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
-			       struct btrfs_root *root,
-			       struct extent_io_tree *unpin)
+			       struct btrfs_root *root)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct extent_io_tree *unpin;
 	u64 start;
 	u64 end;
 	int ret;
 
+	if (fs_info->pinned_extents == &fs_info->freed_extents[0])
+		unpin = &fs_info->freed_extents[1];
+	else
+		unpin = &fs_info->freed_extents[0];
+
 	while (1) {
 		ret = find_first_extent_bit(unpin, 0, &start, &end,
 					    EXTENT_DIRTY);
@@ -3186,10 +3666,8 @@ int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
 
 		ret = btrfs_discard_extent(root, start, end + 1 - start);
 
-		/* unlocks the pinned mutex */
-		btrfs_update_pinned_extents(root, start, end + 1 - start, 0);
 		clear_extent_dirty(unpin, start, end, GFP_NOFS);
-
+		unpin_extent_range(root, start, end);
 		cond_resched();
 	}
 
@@ -3199,7 +3677,8 @@ int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
 static int pin_down_bytes(struct btrfs_trans_handle *trans,
 			  struct btrfs_root *root,
 			  struct btrfs_path *path,
-			  u64 bytenr, u64 num_bytes, int is_data,
+			  u64 bytenr, u64 num_bytes,
+			  int is_data, int reserved,
 			  struct extent_buffer **must_clean)
 {
 	int err = 0;
@@ -3208,6 +3687,14 @@ static int pin_down_bytes(struct btrfs_trans_handle *trans,
 	if (is_data)
 		goto pinit;
 
+	/*
+	 * discard is sloooow, and so triggering discards on
+	 * individual btree blocks isn't a good plan.  Just
+	 * pin everything in discard mode.
+	 */
+	if (btrfs_test_opt(root, DISCARD))
+		goto pinit;
+
 	buf = btrfs_find_tree_block(root, bytenr, num_bytes);
 	if (!buf)
 		goto pinit;
@@ -3231,15 +3718,15 @@ static int pin_down_bytes(struct btrfs_trans_handle *trans,
 	}
 	free_extent_buffer(buf);
 pinit:
-	btrfs_set_path_blocking(path);
+	if (path)
+		btrfs_set_path_blocking(path);
 	/* unlocks the pinned mutex */
-	btrfs_update_pinned_extents(root, bytenr, num_bytes, 1);
+	btrfs_pin_extent(root, bytenr, num_bytes, reserved);
 
 	BUG_ON(err < 0);
 	return 0;
 }
 
-
 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
 				struct btrfs_root *root,
 				u64 bytenr, u64 num_bytes, u64 parent,
@@ -3413,7 +3900,7 @@ static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
 		}
 
 		ret = pin_down_bytes(trans, root, path, bytenr,
-				     num_bytes, is_data, &must_clean);
+				     num_bytes, is_data, 0, &must_clean);
 		if (ret > 0)
 			mark_free = 1;
 		BUG_ON(ret < 0);
@@ -3544,8 +4031,7 @@ int btrfs_free_extent(struct btrfs_trans_handle *trans,
 	if (root_objectid == BTRFS_TREE_LOG_OBJECTID) {
 		WARN_ON(owner >= BTRFS_FIRST_FREE_OBJECTID);
 		/* unlocks the pinned mutex */
-		btrfs_update_pinned_extents(root, bytenr, num_bytes, 1);
-		update_reserved_extents(root, bytenr, num_bytes, 0);
+		btrfs_pin_extent(root, bytenr, num_bytes, 1);
 		ret = 0;
 	} else if (owner < BTRFS_FIRST_FREE_OBJECTID) {
 		ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes,
@@ -3585,19 +4071,33 @@ static noinline int
 wait_block_group_cache_progress(struct btrfs_block_group_cache *cache,
 				u64 num_bytes)
 {
+	struct btrfs_caching_control *caching_ctl;
 	DEFINE_WAIT(wait);
 
-	prepare_to_wait(&cache->caching_q, &wait, TASK_UNINTERRUPTIBLE);
-
-	if (block_group_cache_done(cache)) {
-		finish_wait(&cache->caching_q, &wait);
+	caching_ctl = get_caching_control(cache);
+	if (!caching_ctl)
 		return 0;
-	}
-	schedule();
-	finish_wait(&cache->caching_q, &wait);
 
-	wait_event(cache->caching_q, block_group_cache_done(cache) ||
+	wait_event(caching_ctl->wait, block_group_cache_done(cache) ||
 		   (cache->free_space >= num_bytes));
+
+	put_caching_control(caching_ctl);
+	return 0;
+}
+
+static noinline int
+wait_block_group_cache_done(struct btrfs_block_group_cache *cache)
+{
+	struct btrfs_caching_control *caching_ctl;
+	DEFINE_WAIT(wait);
+
+	caching_ctl = get_caching_control(cache);
+	if (!caching_ctl)
+		return 0;
+
+	wait_event(caching_ctl->wait, block_group_cache_done(cache));
+
+	put_caching_control(caching_ctl);
 	return 0;
 }
 
@@ -3635,6 +4135,8 @@ static noinline int find_free_extent(struct btrfs_trans_handle *trans,
 	int last_ptr_loop = 0;
 	int loop = 0;
 	bool found_uncached_bg = false;
+	bool failed_cluster_refill = false;
+	bool failed_alloc = false;
 
 	WARN_ON(num_bytes < root->sectorsize);
 	btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
@@ -3732,7 +4234,16 @@ have_block_group:
 		if (unlikely(block_group->ro))
 			goto loop;
 
-		if (last_ptr) {
+		/*
+		 * Ok we want to try and use the cluster allocator, so lets look
+		 * there, unless we are on LOOP_NO_EMPTY_SIZE, since we will
+		 * have tried the cluster allocator plenty of times at this
+		 * point and not have found anything, so we are likely way too
+		 * fragmented for the clustering stuff to find anything, so lets
+		 * just skip it and let the allocator find whatever block it can
+		 * find
+		 */
+		if (last_ptr && loop < LOOP_NO_EMPTY_SIZE) {
 			/*
 			 * the refill lock keeps out other
 			 * people trying to start a new cluster
@@ -3807,9 +4318,11 @@ refill_cluster:
 					spin_unlock(&last_ptr->refill_lock);
 					goto checks;
 				}
-			} else if (!cached && loop > LOOP_CACHING_NOWAIT) {
+			} else if (!cached && loop > LOOP_CACHING_NOWAIT
+				   && !failed_cluster_refill) {
 				spin_unlock(&last_ptr->refill_lock);
 
+				failed_cluster_refill = true;
 				wait_block_group_cache_progress(block_group,
 				       num_bytes + empty_cluster + empty_size);
 				goto have_block_group;
@@ -3821,25 +4334,30 @@ refill_cluster:
 			 * cluster.  Free the cluster we've been trying
 			 * to use, and go to the next block group
 			 */
-			if (loop < LOOP_NO_EMPTY_SIZE) {
-				btrfs_return_cluster_to_free_space(NULL,
-								   last_ptr);
-				spin_unlock(&last_ptr->refill_lock);
-				goto loop;
-			}
+			btrfs_return_cluster_to_free_space(NULL, last_ptr);
 			spin_unlock(&last_ptr->refill_lock);
+			goto loop;
 		}
 
 		offset = btrfs_find_space_for_alloc(block_group, search_start,
 						    num_bytes, empty_size);
-		if (!offset && (cached || (!cached &&
-					   loop == LOOP_CACHING_NOWAIT))) {
-			goto loop;
-		} else if (!offset && (!cached &&
-				       loop > LOOP_CACHING_NOWAIT)) {
+		/*
+		 * If we didn't find a chunk, and we haven't failed on this
+		 * block group before, and this block group is in the middle of
+		 * caching and we are ok with waiting, then go ahead and wait
+		 * for progress to be made, and set failed_alloc to true.
+		 *
+		 * If failed_alloc is true then we've already waited on this
+		 * block group once and should move on to the next block group.
+		 */
+		if (!offset && !failed_alloc && !cached &&
+		    loop > LOOP_CACHING_NOWAIT) {
 			wait_block_group_cache_progress(block_group,
-					num_bytes + empty_size);
+						num_bytes + empty_size);
+			failed_alloc = true;
 			goto have_block_group;
+		} else if (!offset) {
+			goto loop;
 		}
 checks:
 		search_start = stripe_align(root, offset);
@@ -3881,9 +4399,13 @@ checks:
 					     search_start - offset);
 		BUG_ON(offset > search_start);
 
+		update_reserved_extents(block_group, num_bytes, 1);
+
 		/* we are all good, lets return */
 		break;
 loop:
+		failed_cluster_refill = false;
+		failed_alloc = false;
 		btrfs_put_block_group(block_group);
 	}
 	up_read(&space_info->groups_sem);
@@ -3941,21 +4463,32 @@ loop:
 	return ret;
 }
 
-static void dump_space_info(struct btrfs_space_info *info, u64 bytes)
+static void dump_space_info(struct btrfs_space_info *info, u64 bytes,
+			    int dump_block_groups)
 {
 	struct btrfs_block_group_cache *cache;
 
+	spin_lock(&info->lock);
 	printk(KERN_INFO "space_info has %llu free, is %sfull\n",
 	       (unsigned long long)(info->total_bytes - info->bytes_used -
-				    info->bytes_pinned - info->bytes_reserved),
+				    info->bytes_pinned - info->bytes_reserved -
+				    info->bytes_super),
 	       (info->full) ? "" : "not ");
 	printk(KERN_INFO "space_info total=%llu, pinned=%llu, delalloc=%llu,"
-	       " may_use=%llu, used=%llu\n",
+	       " may_use=%llu, used=%llu, root=%llu, super=%llu, reserved=%llu"
+	       "\n",
 	       (unsigned long long)info->total_bytes,
 	       (unsigned long long)info->bytes_pinned,
 	       (unsigned long long)info->bytes_delalloc,
 	       (unsigned long long)info->bytes_may_use,
-	       (unsigned long long)info->bytes_used);
+	       (unsigned long long)info->bytes_used,
+	       (unsigned long long)info->bytes_root,
+	       (unsigned long long)info->bytes_super,
+	       (unsigned long long)info->bytes_reserved);
+	spin_unlock(&info->lock);
+
+	if (!dump_block_groups)
+		return;
 
 	down_read(&info->groups_sem);
 	list_for_each_entry(cache, &info->block_groups, list) {
@@ -3973,12 +4506,12 @@ static void dump_space_info(struct btrfs_space_info *info, u64 bytes)
 	up_read(&info->groups_sem);
 }
 
-static int __btrfs_reserve_extent(struct btrfs_trans_handle *trans,
-				  struct btrfs_root *root,
-				  u64 num_bytes, u64 min_alloc_size,
-				  u64 empty_size, u64 hint_byte,
-				  u64 search_end, struct btrfs_key *ins,
-				  u64 data)
+int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
+			 struct btrfs_root *root,
+			 u64 num_bytes, u64 min_alloc_size,
+			 u64 empty_size, u64 hint_byte,
+			 u64 search_end, struct btrfs_key *ins,
+			 u64 data)
 {
 	int ret;
 	u64 search_start = 0;
@@ -4023,7 +4556,7 @@ again:
 		printk(KERN_ERR "btrfs allocation failed flags %llu, "
 		       "wanted %llu\n", (unsigned long long)data,
 		       (unsigned long long)num_bytes);
-		dump_space_info(sinfo, num_bytes);
+		dump_space_info(sinfo, num_bytes, 1);
 	}
 
 	return ret;
@@ -4044,25 +4577,8 @@ int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len)
 	ret = btrfs_discard_extent(root, start, len);
 
 	btrfs_add_free_space(cache, start, len);
+	update_reserved_extents(cache, len, 0);
 	btrfs_put_block_group(cache);
-	update_reserved_extents(root, start, len, 0);
-
-	return ret;
-}
-
-int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
-				  struct btrfs_root *root,
-				  u64 num_bytes, u64 min_alloc_size,
-				  u64 empty_size, u64 hint_byte,
-				  u64 search_end, struct btrfs_key *ins,
-				  u64 data)
-{
-	int ret;
-	ret = __btrfs_reserve_extent(trans, root, num_bytes, min_alloc_size,
-				     empty_size, hint_byte, search_end, ins,
-				     data);
-	if (!ret)
-		update_reserved_extents(root, ins->objectid, ins->offset, 1);
 
 	return ret;
 }
@@ -4223,15 +4739,46 @@ int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
 {
 	int ret;
 	struct btrfs_block_group_cache *block_group;
+	struct btrfs_caching_control *caching_ctl;
+	u64 start = ins->objectid;
+	u64 num_bytes = ins->offset;
 
 	block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid);
 	cache_block_group(block_group);
-	wait_event(block_group->caching_q,
-		   block_group_cache_done(block_group));
+	caching_ctl = get_caching_control(block_group);
 
-	ret = btrfs_remove_free_space(block_group, ins->objectid,
-				      ins->offset);
-	BUG_ON(ret);
+	if (!caching_ctl) {
+		BUG_ON(!block_group_cache_done(block_group));
+		ret = btrfs_remove_free_space(block_group, start, num_bytes);
+		BUG_ON(ret);
+	} else {
+		mutex_lock(&caching_ctl->mutex);
+
+		if (start >= caching_ctl->progress) {
+			ret = add_excluded_extent(root, start, num_bytes);
+			BUG_ON(ret);
+		} else if (start + num_bytes <= caching_ctl->progress) {
+			ret = btrfs_remove_free_space(block_group,
+						      start, num_bytes);
+			BUG_ON(ret);
+		} else {
+			num_bytes = caching_ctl->progress - start;
+			ret = btrfs_remove_free_space(block_group,
+						      start, num_bytes);
+			BUG_ON(ret);
+
+			start = caching_ctl->progress;
+			num_bytes = ins->objectid + ins->offset -
+				    caching_ctl->progress;
+			ret = add_excluded_extent(root, start, num_bytes);
+			BUG_ON(ret);
+		}
+
+		mutex_unlock(&caching_ctl->mutex);
+		put_caching_control(caching_ctl);
+	}
+
+	update_reserved_extents(block_group, ins->offset, 1);
 	btrfs_put_block_group(block_group);
 	ret = alloc_reserved_file_extent(trans, root, 0, root_objectid,
 					 0, owner, offset, ins, 1);
@@ -4255,9 +4802,9 @@ static int alloc_tree_block(struct btrfs_trans_handle *trans,
 	int ret;
 	u64 flags = 0;
 
-	ret = __btrfs_reserve_extent(trans, root, num_bytes, num_bytes,
-				     empty_size, hint_byte, search_end,
-				     ins, 0);
+	ret = btrfs_reserve_extent(trans, root, num_bytes, num_bytes,
+				   empty_size, hint_byte, search_end,
+				   ins, 0);
 	if (ret)
 		return ret;
 
@@ -4268,7 +4815,6 @@ static int alloc_tree_block(struct btrfs_trans_handle *trans,
 	} else
 		BUG_ON(parent > 0);
 
-	update_reserved_extents(root, ins->objectid, ins->offset, 1);
 	if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
 		struct btrfs_delayed_extent_op *extent_op;
 		extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
@@ -4347,452 +4893,108 @@ struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
 	return buf;
 }
 
-#if 0
-int btrfs_drop_leaf_ref(struct btrfs_trans_handle *trans,
-			struct btrfs_root *root, struct extent_buffer *leaf)
-{
-	u64 disk_bytenr;
-	u64 num_bytes;
-	struct btrfs_key key;
-	struct btrfs_file_extent_item *fi;
-	u32 nritems;
-	int i;
-	int ret;
-
-	BUG_ON(!btrfs_is_leaf(leaf));
-	nritems = btrfs_header_nritems(leaf);
-
-	for (i = 0; i < nritems; i++) {
-		cond_resched();
-		btrfs_item_key_to_cpu(leaf, &key, i);
-
-		/* only extents have references, skip everything else */
-		if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
-			continue;
-
-		fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
-
-		/* inline extents live in the btree, they don't have refs */
-		if (btrfs_file_extent_type(leaf, fi) ==
-		    BTRFS_FILE_EXTENT_INLINE)
-			continue;
-
-		disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
-
-		/* holes don't have refs */
-		if (disk_bytenr == 0)
-			continue;
-
-		num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
-		ret = btrfs_free_extent(trans, root, disk_bytenr, num_bytes,
-					leaf->start, 0, key.objectid, 0);
-		BUG_ON(ret);
-	}
-	return 0;
-}
-
-static noinline int cache_drop_leaf_ref(struct btrfs_trans_handle *trans,
-					struct btrfs_root *root,
-					struct btrfs_leaf_ref *ref)
-{
-	int i;
-	int ret;
-	struct btrfs_extent_info *info;
-	struct refsort *sorted;
-
-	if (ref->nritems == 0)
-		return 0;
-
-	sorted = kmalloc(sizeof(*sorted) * ref->nritems, GFP_NOFS);
-	for (i = 0; i < ref->nritems; i++) {
-		sorted[i].bytenr = ref->extents[i].bytenr;
-		sorted[i].slot = i;
-	}
-	sort(sorted, ref->nritems, sizeof(struct refsort), refsort_cmp, NULL);
-
-	/*
-	 * the items in the ref were sorted when the ref was inserted
-	 * into the ref cache, so this is already in order
-	 */
-	for (i = 0; i < ref->nritems; i++) {
-		info = ref->extents + sorted[i].slot;
-		ret = btrfs_free_extent(trans, root, info->bytenr,
-					  info->num_bytes, ref->bytenr,
-					  ref->owner, ref->generation,
-					  info->objectid, 0);
-
-		atomic_inc(&root->fs_info->throttle_gen);
-		wake_up(&root->fs_info->transaction_throttle);
-		cond_resched();
-
-		BUG_ON(ret);
-		info++;
-	}
-
-	kfree(sorted);
-	return 0;
-}
-
-
-static int drop_snap_lookup_refcount(struct btrfs_trans_handle *trans,
-				     struct btrfs_root *root, u64 start,
-				     u64 len, u32 *refs)
-{
-	int ret;
-
-	ret = btrfs_lookup_extent_refs(trans, root, start, len, refs);
-	BUG_ON(ret);
-
-#if 0 /* some debugging code in case we see problems here */
-	/* if the refs count is one, it won't get increased again.  But
-	 * if the ref count is > 1, someone may be decreasing it at
-	 * the same time we are.
-	 */
-	if (*refs != 1) {
-		struct extent_buffer *eb = NULL;
-		eb = btrfs_find_create_tree_block(root, start, len);
-		if (eb)
-			btrfs_tree_lock(eb);
-
-		mutex_lock(&root->fs_info->alloc_mutex);
-		ret = lookup_extent_ref(NULL, root, start, len, refs);
-		BUG_ON(ret);
-		mutex_unlock(&root->fs_info->alloc_mutex);
-
-		if (eb) {
-			btrfs_tree_unlock(eb);
-			free_extent_buffer(eb);
-		}
-		if (*refs == 1) {
-			printk(KERN_ERR "btrfs block %llu went down to one "
-			       "during drop_snap\n", (unsigned long long)start);
-		}
-
-	}
-#endif
-
-	cond_resched();
-	return ret;
-}
+struct walk_control {
+	u64 refs[BTRFS_MAX_LEVEL];
+	u64 flags[BTRFS_MAX_LEVEL];
+	struct btrfs_key update_progress;
+	int stage;
+	int level;
+	int shared_level;
+	int update_ref;
+	int keep_locks;
+	int reada_slot;
+	int reada_count;
+};
 
+#define DROP_REFERENCE	1
+#define UPDATE_BACKREF	2
 
-/*
- * this is used while deleting old snapshots, and it drops the refs
- * on a whole subtree starting from a level 1 node.
- *
- * The idea is to sort all the leaf pointers, and then drop the
- * ref on all the leaves in order.  Most of the time the leaves
- * will have ref cache entries, so no leaf IOs will be required to
- * find the extents they have references on.
- *
- * For each leaf, any references it has are also dropped in order
- *
- * This ends up dropping the references in something close to optimal
- * order for reading and modifying the extent allocation tree.
- */
-static noinline int drop_level_one_refs(struct btrfs_trans_handle *trans,
-					struct btrfs_root *root,
-					struct btrfs_path *path)
+static noinline void reada_walk_down(struct btrfs_trans_handle *trans,
+				     struct btrfs_root *root,
+				     struct walk_control *wc,
+				     struct btrfs_path *path)
 {
 	u64 bytenr;
-	u64 root_owner;
-	u64 root_gen;
-	struct extent_buffer *eb = path->nodes[1];
-	struct extent_buffer *leaf;
-	struct btrfs_leaf_ref *ref;
-	struct refsort *sorted = NULL;
-	int nritems = btrfs_header_nritems(eb);
+	u64 generation;
+	u64 refs;
+	u64 flags;
+	u64 last = 0;
+	u32 nritems;
+	u32 blocksize;
+	struct btrfs_key key;
+	struct extent_buffer *eb;
 	int ret;
-	int i;
-	int refi = 0;
-	int slot = path->slots[1];
-	u32 blocksize = btrfs_level_size(root, 0);
-	u32 refs;
-
-	if (nritems == 0)
-		goto out;
-
-	root_owner = btrfs_header_owner(eb);
-	root_gen = btrfs_header_generation(eb);
-	sorted = kmalloc(sizeof(*sorted) * nritems, GFP_NOFS);
+	int slot;
+	int nread = 0;
 
-	/*
-	 * step one, sort all the leaf pointers so we don't scribble
-	 * randomly into the extent allocation tree
-	 */
-	for (i = slot; i < nritems; i++) {
-		sorted[refi].bytenr = btrfs_node_blockptr(eb, i);
-		sorted[refi].slot = i;
-		refi++;
+	if (path->slots[wc->level] < wc->reada_slot) {
+		wc->reada_count = wc->reada_count * 2 / 3;
+		wc->reada_count = max(wc->reada_count, 2);
+	} else {
+		wc->reada_count = wc->reada_count * 3 / 2;
+		wc->reada_count = min_t(int, wc->reada_count,
+					BTRFS_NODEPTRS_PER_BLOCK(root));
 	}
 
-	/*
-	 * nritems won't be zero, but if we're picking up drop_snapshot
-	 * after a crash, slot might be > 0, so double check things
-	 * just in case.
-	 */
-	if (refi == 0)
-		goto out;
+	eb = path->nodes[wc->level];
+	nritems = btrfs_header_nritems(eb);
+	blocksize = btrfs_level_size(root, wc->level - 1);
 
-	sort(sorted, refi, sizeof(struct refsort), refsort_cmp, NULL);
+	for (slot = path->slots[wc->level]; slot < nritems; slot++) {
+		if (nread >= wc->reada_count)
+			break;
 
-	/*
-	 * the first loop frees everything the leaves point to
-	 */
-	for (i = 0; i < refi; i++) {
-		u64 ptr_gen;
+		cond_resched();
+		bytenr = btrfs_node_blockptr(eb, slot);
+		generation = btrfs_node_ptr_generation(eb, slot);
 
-		bytenr = sorted[i].bytenr;
+		if (slot == path->slots[wc->level])
+			goto reada;
 
-		/*
-		 * check the reference count on this leaf.  If it is > 1
-		 * we just decrement it below and don't update any
-		 * of the refs the leaf points to.
-		 */
-		ret = drop_snap_lookup_refcount(trans, root, bytenr,
-						blocksize, &refs);
-		BUG_ON(ret);
-		if (refs != 1)
+		if (wc->stage == UPDATE_BACKREF &&
+		    generation <= root->root_key.offset)
 			continue;
 
-		ptr_gen = btrfs_node_ptr_generation(eb, sorted[i].slot);
-
-		/*
-		 * the leaf only had one reference, which means the
-		 * only thing pointing to this leaf is the snapshot
-		 * we're deleting.  It isn't possible for the reference
-		 * count to increase again later
-		 *
-		 * The reference cache is checked for the leaf,
-		 * and if found we'll be able to drop any refs held by
-		 * the leaf without needing to read it in.
-		 */
-		ref = btrfs_lookup_leaf_ref(root, bytenr);
-		if (ref && ref->generation != ptr_gen) {
-			btrfs_free_leaf_ref(root, ref);
-			ref = NULL;
-		}
-		if (ref) {
-			ret = cache_drop_leaf_ref(trans, root, ref);
-			BUG_ON(ret);
-			btrfs_remove_leaf_ref(root, ref);
-			btrfs_free_leaf_ref(root, ref);
-		} else {
-			/*
-			 * the leaf wasn't in the reference cache, so
-			 * we have to read it.
-			 */
-			leaf = read_tree_block(root, bytenr, blocksize,
-					       ptr_gen);
-			ret = btrfs_drop_leaf_ref(trans, root, leaf);
-			BUG_ON(ret);
-			free_extent_buffer(leaf);
-		}
-		atomic_inc(&root->fs_info->throttle_gen);
-		wake_up(&root->fs_info->transaction_throttle);
-		cond_resched();
-	}
-
-	/*
-	 * run through the loop again to free the refs on the leaves.
-	 * This is faster than doing it in the loop above because
-	 * the leaves are likely to be clustered together.  We end up
-	 * working in nice chunks on the extent allocation tree.
-	 */
-	for (i = 0; i < refi; i++) {
-		bytenr = sorted[i].bytenr;
-		ret = btrfs_free_extent(trans, root, bytenr,
-					blocksize, eb->start,
-					root_owner, root_gen, 0, 1);
+		/* We don't lock the tree block, it's OK to be racy here */
+		ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
+					       &refs, &flags);
 		BUG_ON(ret);
+		BUG_ON(refs == 0);
 
-		atomic_inc(&root->fs_info->throttle_gen);
-		wake_up(&root->fs_info->transaction_throttle);
-		cond_resched();
-	}
-out:
-	kfree(sorted);
-
-	/*
-	 * update the path to show we've processed the entire level 1
-	 * node.  This will get saved into the root's drop_snapshot_progress
-	 * field so these drops are not repeated again if this transaction
-	 * commits.
-	 */
-	path->slots[1] = nritems;
-	return 0;
-}
-
-/*
- * helper function for drop_snapshot, this walks down the tree dropping ref
- * counts as it goes.
- */
-static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
-				   struct btrfs_root *root,
-				   struct btrfs_path *path, int *level)
-{
-	u64 root_owner;
-	u64 root_gen;
-	u64 bytenr;
-	u64 ptr_gen;
-	struct extent_buffer *next;
-	struct extent_buffer *cur;
-	struct extent_buffer *parent;
-	u32 blocksize;
-	int ret;
-	u32 refs;
-
-	WARN_ON(*level < 0);
-	WARN_ON(*level >= BTRFS_MAX_LEVEL);
-	ret = drop_snap_lookup_refcount(trans, root, path->nodes[*level]->start,
-				path->nodes[*level]->len, &refs);
-	BUG_ON(ret);
-	if (refs > 1)
-		goto out;
-
-	/*
-	 * walk down to the last node level and free all the leaves
-	 */
-	while (*level >= 0) {
-		WARN_ON(*level < 0);
-		WARN_ON(*level >= BTRFS_MAX_LEVEL);
-		cur = path->nodes[*level];
-
-		if (btrfs_header_level(cur) != *level)
-			WARN_ON(1);
-
-		if (path->slots[*level] >=
-		    btrfs_header_nritems(cur))
-			break;
+		if (wc->stage == DROP_REFERENCE) {
+			if (refs == 1)
+				goto reada;
 
-		/* the new code goes down to level 1 and does all the
-		 * leaves pointed to that node in bulk.  So, this check
-		 * for level 0 will always be false.
-		 *
-		 * But, the disk format allows the drop_snapshot_progress
-		 * field in the root to leave things in a state where
-		 * a leaf will need cleaning up here.  If someone crashes
-		 * with the old code and then boots with the new code,
-		 * we might find a leaf here.
-		 */
-		if (*level == 0) {
-			ret = btrfs_drop_leaf_ref(trans, root, cur);
-			BUG_ON(ret);
-			break;
+			if (wc->level == 1 &&
+			    (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
+				continue;
+			if (!wc->update_ref ||
+			    generation <= root->root_key.offset)
+				continue;
+			btrfs_node_key_to_cpu(eb, &key, slot);
+			ret = btrfs_comp_cpu_keys(&key,
+						  &wc->update_progress);
+			if (ret < 0)
+				continue;
+		} else {
+			if (wc->level == 1 &&
+			    (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
+				continue;
 		}
-
-		/*
-		 * once we get to level one, process the whole node
-		 * at once, including everything below it.
-		 */
-		if (*level == 1) {
-			ret = drop_level_one_refs(trans, root, path);
-			BUG_ON(ret);
+reada:
+		ret = readahead_tree_block(root, bytenr, blocksize,
+					   generation);
+		if (ret)
 			break;
-		}
-
-		bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
-		ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
-		blocksize = btrfs_level_size(root, *level - 1);
-
-		ret = drop_snap_lookup_refcount(trans, root, bytenr,
-						blocksize, &refs);
-		BUG_ON(ret);
-
-		/*
-		 * if there is more than one reference, we don't need
-		 * to read that node to drop any references it has.  We
-		 * just drop the ref we hold on that node and move on to the
-		 * next slot in this level.
-		 */
-		if (refs != 1) {
-			parent = path->nodes[*level];
-			root_owner = btrfs_header_owner(parent);
-			root_gen = btrfs_header_generation(parent);
-			path->slots[*level]++;
-
-			ret = btrfs_free_extent(trans, root, bytenr,
-						blocksize, parent->start,
-						root_owner, root_gen,
-						*level - 1, 1);
-			BUG_ON(ret);
-
-			atomic_inc(&root->fs_info->throttle_gen);
-			wake_up(&root->fs_info->transaction_throttle);
-			cond_resched();
-
-			continue;
-		}
-
-		/*
-		 * we need to keep freeing things in the next level down.
-		 * read the block and loop around to process it
-		 */
-		next = read_tree_block(root, bytenr, blocksize, ptr_gen);
-		WARN_ON(*level <= 0);
-		if (path->nodes[*level-1])
-			free_extent_buffer(path->nodes[*level-1]);
-		path->nodes[*level-1] = next;
-		*level = btrfs_header_level(next);
-		path->slots[*level] = 0;
-		cond_resched();
+		last = bytenr + blocksize;
+		nread++;
 	}
-out:
-	WARN_ON(*level < 0);
-	WARN_ON(*level >= BTRFS_MAX_LEVEL);
-
-	if (path->nodes[*level] == root->node) {
-		parent = path->nodes[*level];
-		bytenr = path->nodes[*level]->start;
-	} else {
-		parent = path->nodes[*level + 1];
-		bytenr = btrfs_node_blockptr(parent, path->slots[*level + 1]);
-	}
-
-	blocksize = btrfs_level_size(root, *level);
-	root_owner = btrfs_header_owner(parent);
-	root_gen = btrfs_header_generation(parent);
-
-	/*
-	 * cleanup and free the reference on the last node
-	 * we processed
-	 */
-	ret = btrfs_free_extent(trans, root, bytenr, blocksize,
-				  parent->start, root_owner, root_gen,
-				  *level, 1);
-	free_extent_buffer(path->nodes[*level]);
-	path->nodes[*level] = NULL;
-
-	*level += 1;
-	BUG_ON(ret);
-
-	cond_resched();
-	return 0;
+	wc->reada_slot = slot;
 }
-#endif
-
-struct walk_control {
-	u64 refs[BTRFS_MAX_LEVEL];
-	u64 flags[BTRFS_MAX_LEVEL];
-	struct btrfs_key update_progress;
-	int stage;
-	int level;
-	int shared_level;
-	int update_ref;
-	int keep_locks;
-};
-
-#define DROP_REFERENCE	1
-#define UPDATE_BACKREF	2
 
 /*
  * hepler to process tree block while walking down the tree.
  *
- * when wc->stage == DROP_REFERENCE, this function checks
- * reference count of the block. if the block is shared and
- * we need update back refs for the subtree rooted at the
- * block, this function changes wc->stage to UPDATE_BACKREF
- *
  * when wc->stage == UPDATE_BACKREF, this function updates
  * back refs for pointers in the block.
  *
@@ -4801,11 +5003,10 @@ struct walk_control {
 static noinline int walk_down_proc(struct btrfs_trans_handle *trans,
 				   struct btrfs_root *root,
 				   struct btrfs_path *path,
-				   struct walk_control *wc)
+				   struct walk_control *wc, int lookup_info)
 {
 	int level = wc->level;
 	struct extent_buffer *eb = path->nodes[level];
-	struct btrfs_key key;
 	u64 flag = BTRFS_BLOCK_FLAG_FULL_BACKREF;
 	int ret;
 
@@ -4817,8 +5018,9 @@ static noinline int walk_down_proc(struct btrfs_trans_handle *trans,
 	 * when reference count of tree block is 1, it won't increase
 	 * again. once full backref flag is set, we never clear it.
 	 */
-	if ((wc->stage == DROP_REFERENCE && wc->refs[level] != 1) ||
-	    (wc->stage == UPDATE_BACKREF && !(wc->flags[level] & flag))) {
+	if (lookup_info &&
+	    ((wc->stage == DROP_REFERENCE && wc->refs[level] != 1) ||
+	     (wc->stage == UPDATE_BACKREF && !(wc->flags[level] & flag)))) {
 		BUG_ON(!path->locks[level]);
 		ret = btrfs_lookup_extent_info(trans, root,
 					       eb->start, eb->len,
@@ -4828,21 +5030,6 @@ static noinline int walk_down_proc(struct btrfs_trans_handle *trans,
 		BUG_ON(wc->refs[level] == 0);
 	}
 
-	if (wc->stage == DROP_REFERENCE &&
-	    wc->update_ref && wc->refs[level] > 1) {
-		BUG_ON(eb == root->node);
-		BUG_ON(path->slots[level] > 0);
-		if (level == 0)
-			btrfs_item_key_to_cpu(eb, &key, path->slots[level]);
-		else
-			btrfs_node_key_to_cpu(eb, &key, path->slots[level]);
-		if (btrfs_header_owner(eb) == root->root_key.objectid &&
-		    btrfs_comp_cpu_keys(&key, &wc->update_progress) >= 0) {
-			wc->stage = UPDATE_BACKREF;
-			wc->shared_level = level;
-		}
-	}
-
 	if (wc->stage == DROP_REFERENCE) {
 		if (wc->refs[level] > 1)
 			return 1;
@@ -4879,6 +5066,136 @@ static noinline int walk_down_proc(struct btrfs_trans_handle *trans,
 }
 
 /*
+ * hepler to process tree block pointer.
+ *
+ * when wc->stage == DROP_REFERENCE, this function checks
+ * reference count of the block pointed to. if the block
+ * is shared and we need update back refs for the subtree
+ * rooted at the block, this function changes wc->stage to
+ * UPDATE_BACKREF. if the block is shared and there is no
+ * need to update back, this function drops the reference
+ * to the block.
+ *
+ * NOTE: return value 1 means we should stop walking down.
+ */
+static noinline int do_walk_down(struct btrfs_trans_handle *trans,
+				 struct btrfs_root *root,
+				 struct btrfs_path *path,
+				 struct walk_control *wc, int *lookup_info)
+{
+	u64 bytenr;
+	u64 generation;
+	u64 parent;
+	u32 blocksize;
+	struct btrfs_key key;
+	struct extent_buffer *next;
+	int level = wc->level;
+	int reada = 0;
+	int ret = 0;
+
+	generation = btrfs_node_ptr_generation(path->nodes[level],
+					       path->slots[level]);
+	/*
+	 * if the lower level block was created before the snapshot
+	 * was created, we know there is no need to update back refs
+	 * for the subtree
+	 */
+	if (wc->stage == UPDATE_BACKREF &&
+	    generation <= root->root_key.offset) {
+		*lookup_info = 1;
+		return 1;
+	}
+
+	bytenr = btrfs_node_blockptr(path->nodes[level], path->slots[level]);
+	blocksize = btrfs_level_size(root, level - 1);
+
+	next = btrfs_find_tree_block(root, bytenr, blocksize);
+	if (!next) {
+		next = btrfs_find_create_tree_block(root, bytenr, blocksize);
+		reada = 1;
+	}
+	btrfs_tree_lock(next);
+	btrfs_set_lock_blocking(next);
+
+	ret = btrfs_lookup_extent_info(trans, root, bytenr, blocksize,
+				       &wc->refs[level - 1],
+				       &wc->flags[level - 1]);
+	BUG_ON(ret);
+	BUG_ON(wc->refs[level - 1] == 0);
+	*lookup_info = 0;
+
+	if (wc->stage == DROP_REFERENCE) {
+		if (wc->refs[level - 1] > 1) {
+			if (level == 1 &&
+			    (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
+				goto skip;
+
+			if (!wc->update_ref ||
+			    generation <= root->root_key.offset)
+				goto skip;
+
+			btrfs_node_key_to_cpu(path->nodes[level], &key,
+					      path->slots[level]);
+			ret = btrfs_comp_cpu_keys(&key, &wc->update_progress);
+			if (ret < 0)
+				goto skip;
+
+			wc->stage = UPDATE_BACKREF;
+			wc->shared_level = level - 1;
+		}
+	} else {
+		if (level == 1 &&
+		    (wc->flags[0] & BTRFS_BLOCK_FLAG_FULL_BACKREF))
+			goto skip;
+	}
+
+	if (!btrfs_buffer_uptodate(next, generation)) {
+		btrfs_tree_unlock(next);
+		free_extent_buffer(next);
+		next = NULL;
+		*lookup_info = 1;
+	}
+
+	if (!next) {
+		if (reada && level == 1)
+			reada_walk_down(trans, root, wc, path);
+		next = read_tree_block(root, bytenr, blocksize, generation);
+		btrfs_tree_lock(next);
+		btrfs_set_lock_blocking(next);
+	}
+
+	level--;
+	BUG_ON(level != btrfs_header_level(next));
+	path->nodes[level] = next;
+	path->slots[level] = 0;
+	path->locks[level] = 1;
+	wc->level = level;
+	if (wc->level == 1)
+		wc->reada_slot = 0;
+	return 0;
+skip:
+	wc->refs[level - 1] = 0;
+	wc->flags[level - 1] = 0;
+	if (wc->stage == DROP_REFERENCE) {
+		if (wc->flags[level] & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
+			parent = path->nodes[level]->start;
+		} else {
+			BUG_ON(root->root_key.objectid !=
+			       btrfs_header_owner(path->nodes[level]));
+			parent = 0;
+		}
+
+		ret = btrfs_free_extent(trans, root, bytenr, blocksize, parent,
+					root->root_key.objectid, level - 1, 0);
+		BUG_ON(ret);
+	}
+	btrfs_tree_unlock(next);
+	free_extent_buffer(next);
+	*lookup_info = 1;
+	return 1;
+}
+
+/*
  * hepler to process tree block while walking up the tree.
  *
  * when wc->stage == DROP_REFERENCE, this function drops
@@ -4905,7 +5222,6 @@ static noinline int walk_up_proc(struct btrfs_trans_handle *trans,
 		if (level < wc->shared_level)
 			goto out;
 
-		BUG_ON(wc->refs[level] <= 1);
 		ret = find_next_key(path, level + 1, &wc->update_progress);
 		if (ret > 0)
 			wc->update_ref = 0;
@@ -4936,8 +5252,6 @@ static noinline int walk_up_proc(struct btrfs_trans_handle *trans,
 				path->locks[level] = 0;
 				return 1;
 			}
-		} else {
-			BUG_ON(level != 0);
 		}
 	}
 
@@ -4990,39 +5304,28 @@ static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
 				   struct btrfs_path *path,
 				   struct walk_control *wc)
 {
-	struct extent_buffer *next;
-	struct extent_buffer *cur;
-	u64 bytenr;
-	u64 ptr_gen;
-	u32 blocksize;
 	int level = wc->level;
+	int lookup_info = 1;
 	int ret;
 
 	while (level >= 0) {
-		cur = path->nodes[level];
-		BUG_ON(path->slots[level] >= btrfs_header_nritems(cur));
+		if (path->slots[level] >=
+		    btrfs_header_nritems(path->nodes[level]))
+			break;
 
-		ret = walk_down_proc(trans, root, path, wc);
+		ret = walk_down_proc(trans, root, path, wc, lookup_info);
 		if (ret > 0)
 			break;
 
 		if (level == 0)
 			break;
 
-		bytenr = btrfs_node_blockptr(cur, path->slots[level]);
-		blocksize = btrfs_level_size(root, level - 1);
-		ptr_gen = btrfs_node_ptr_generation(cur, path->slots[level]);
-
-		next = read_tree_block(root, bytenr, blocksize, ptr_gen);
-		btrfs_tree_lock(next);
-		btrfs_set_lock_blocking(next);
-
-		level--;
-		BUG_ON(level != btrfs_header_level(next));
-		path->nodes[level] = next;
-		path->slots[level] = 0;
-		path->locks[level] = 1;
-		wc->level = level;
+		ret = do_walk_down(trans, root, path, wc, &lookup_info);
+		if (ret > 0) {
+			path->slots[level]++;
+			continue;
+		}
+		level = wc->level;
 	}
 	return 0;
 }
@@ -5112,9 +5415,7 @@ int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref)
 			err = ret;
 			goto out;
 		}
-		btrfs_node_key_to_cpu(path->nodes[level], &key,
-				      path->slots[level]);
-		WARN_ON(memcmp(&key, &wc->update_progress, sizeof(key)));
+		WARN_ON(ret > 0);
 
 		/*
 		 * unlock our path, this is safe because only this
@@ -5149,6 +5450,7 @@ int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref)
 	wc->stage = DROP_REFERENCE;
 	wc->update_ref = update_ref;
 	wc->keep_locks = 0;
+	wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
 
 	while (1) {
 		ret = walk_down_tree(trans, root, path, wc);
@@ -5201,9 +5503,24 @@ int btrfs_drop_snapshot(struct btrfs_root *root, int update_ref)
 	ret = btrfs_del_root(trans, tree_root, &root->root_key);
 	BUG_ON(ret);
 
-	free_extent_buffer(root->node);
-	free_extent_buffer(root->commit_root);
-	kfree(root);
+	if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
+		ret = btrfs_find_last_root(tree_root, root->root_key.objectid,
+					   NULL, NULL);
+		BUG_ON(ret < 0);
+		if (ret > 0) {
+			ret = btrfs_del_orphan_item(trans, tree_root,
+						    root->root_key.objectid);
+			BUG_ON(ret);
+		}
+	}
+
+	if (root->in_radix) {
+		btrfs_free_fs_root(tree_root->fs_info, root);
+	} else {
+		free_extent_buffer(root->node);
+		free_extent_buffer(root->commit_root);
+		kfree(root);
+	}
 out:
 	btrfs_end_transaction(trans, tree_root);
 	kfree(wc);
@@ -5255,6 +5572,7 @@ int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
 	wc->stage = DROP_REFERENCE;
 	wc->update_ref = 0;
 	wc->keep_locks = 1;
+	wc->reada_count = BTRFS_NODEPTRS_PER_BLOCK(root);
 
 	while (1) {
 		wret = walk_down_tree(trans, root, path, wc);
@@ -5397,9 +5715,9 @@ static noinline int relocate_data_extent(struct inode *reloc_inode,
 	lock_extent(&BTRFS_I(reloc_inode)->io_tree, start, end, GFP_NOFS);
 	while (1) {
 		int ret;
-		spin_lock(&em_tree->lock);
+		write_lock(&em_tree->lock);
 		ret = add_extent_mapping(em_tree, em);
-		spin_unlock(&em_tree->lock);
+		write_unlock(&em_tree->lock);
 		if (ret != -EEXIST) {
 			free_extent_map(em);
 			break;
@@ -6842,287 +7160,86 @@ int btrfs_prepare_block_group_relocation(struct btrfs_root *root,
 	return 0;
 }
 
-#if 0
-static int __insert_orphan_inode(struct btrfs_trans_handle *trans,
-				 struct btrfs_root *root,
-				 u64 objectid, u64 size)
-{
-	struct btrfs_path *path;
-	struct btrfs_inode_item *item;
-	struct extent_buffer *leaf;
-	int ret;
-
-	path = btrfs_alloc_path();
-	if (!path)
-		return -ENOMEM;
-
-	path->leave_spinning = 1;
-	ret = btrfs_insert_empty_inode(trans, root, path, objectid);
-	if (ret)
-		goto out;
-
-	leaf = path->nodes[0];
-	item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_inode_item);
-	memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item));
-	btrfs_set_inode_generation(leaf, item, 1);
-	btrfs_set_inode_size(leaf, item, size);
-	btrfs_set_inode_mode(leaf, item, S_IFREG | 0600);
-	btrfs_set_inode_flags(leaf, item, BTRFS_INODE_NOCOMPRESS);
-	btrfs_mark_buffer_dirty(leaf);
-	btrfs_release_path(root, path);
-out:
-	btrfs_free_path(path);
-	return ret;
-}
-
-static noinline struct inode *create_reloc_inode(struct btrfs_fs_info *fs_info,
-					struct btrfs_block_group_cache *group)
+/*
+ * checks to see if its even possible to relocate this block group.
+ *
+ * @return - -1 if it's not a good idea to relocate this block group, 0 if its
+ * ok to go ahead and try.
+ */
+int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
 {
-	struct inode *inode = NULL;
-	struct btrfs_trans_handle *trans;
-	struct btrfs_root *root;
-	struct btrfs_key root_key;
-	u64 objectid = BTRFS_FIRST_FREE_OBJECTID;
-	int err = 0;
+	struct btrfs_block_group_cache *block_group;
+	struct btrfs_space_info *space_info;
+	struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
+	struct btrfs_device *device;
+	int full = 0;
+	int ret = 0;
 
-	root_key.objectid = BTRFS_DATA_RELOC_TREE_OBJECTID;
-	root_key.type = BTRFS_ROOT_ITEM_KEY;
-	root_key.offset = (u64)-1;
-	root = btrfs_read_fs_root_no_name(fs_info, &root_key);
-	if (IS_ERR(root))
-		return ERR_CAST(root);
+	block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
 
-	trans = btrfs_start_transaction(root, 1);
-	BUG_ON(!trans);
+	/* odd, couldn't find the block group, leave it alone */
+	if (!block_group)
+		return -1;
 
-	err = btrfs_find_free_objectid(trans, root, objectid, &objectid);
-	if (err)
+	/* no bytes used, we're good */
+	if (!btrfs_block_group_used(&block_group->item))
 		goto out;
 
-	err = __insert_orphan_inode(trans, root, objectid, group->key.offset);
-	BUG_ON(err);
-
-	err = btrfs_insert_file_extent(trans, root, objectid, 0, 0, 0,
-				       group->key.offset, 0, group->key.offset,
-				       0, 0, 0);
-	BUG_ON(err);
-
-	inode = btrfs_iget_locked(root->fs_info->sb, objectid, root);
-	if (inode->i_state & I_NEW) {
-		BTRFS_I(inode)->root = root;
-		BTRFS_I(inode)->location.objectid = objectid;
-		BTRFS_I(inode)->location.type = BTRFS_INODE_ITEM_KEY;
-		BTRFS_I(inode)->location.offset = 0;
-		btrfs_read_locked_inode(inode);
-		unlock_new_inode(inode);
-		BUG_ON(is_bad_inode(inode));
-	} else {
-		BUG_ON(1);
-	}
-	BTRFS_I(inode)->index_cnt = group->key.objectid;
-
-	err = btrfs_orphan_add(trans, inode);
-out:
-	btrfs_end_transaction(trans, root);
-	if (err) {
-		if (inode)
-			iput(inode);
-		inode = ERR_PTR(err);
-	}
-	return inode;
-}
-
-int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len)
-{
-
-	struct btrfs_ordered_sum *sums;
-	struct btrfs_sector_sum *sector_sum;
-	struct btrfs_ordered_extent *ordered;
-	struct btrfs_root *root = BTRFS_I(inode)->root;
-	struct list_head list;
-	size_t offset;
-	int ret;
-	u64 disk_bytenr;
-
-	INIT_LIST_HEAD(&list);
-
-	ordered = btrfs_lookup_ordered_extent(inode, file_pos);
-	BUG_ON(ordered->file_offset != file_pos || ordered->len != len);
-
-	disk_bytenr = file_pos + BTRFS_I(inode)->index_cnt;
-	ret = btrfs_lookup_csums_range(root->fs_info->csum_root, disk_bytenr,
-				       disk_bytenr + len - 1, &list);
-
-	while (!list_empty(&list)) {
-		sums = list_entry(list.next, struct btrfs_ordered_sum, list);
-		list_del_init(&sums->list);
-
-		sector_sum = sums->sums;
-		sums->bytenr = ordered->start;
+	space_info = block_group->space_info;
+	spin_lock(&space_info->lock);
 
-		offset = 0;
-		while (offset < sums->len) {
-			sector_sum->bytenr += ordered->start - disk_bytenr;
-			sector_sum++;
-			offset += root->sectorsize;
-		}
+	full = space_info->full;
 
-		btrfs_add_ordered_sum(inode, ordered, sums);
+	/*
+	 * if this is the last block group we have in this space, we can't
+	 * relocate it unless we're able to allocate a new chunk below.
+	 *
+	 * Otherwise, we need to make sure we have room in the space to handle
+	 * all of the extents from this block group.  If we can, we're good
+	 */
+	if ((space_info->total_bytes != block_group->key.offset) &&
+	   (space_info->bytes_used + space_info->bytes_reserved +
+	    space_info->bytes_pinned + space_info->bytes_readonly +
+	    btrfs_block_group_used(&block_group->item) <
+	    space_info->total_bytes)) {
+		spin_unlock(&space_info->lock);
+		goto out;
 	}
-	btrfs_put_ordered_extent(ordered);
-	return 0;
-}
-
-int btrfs_relocate_block_group(struct btrfs_root *root, u64 group_start)
-{
-	struct btrfs_trans_handle *trans;
-	struct btrfs_path *path;
-	struct btrfs_fs_info *info = root->fs_info;
-	struct extent_buffer *leaf;
-	struct inode *reloc_inode;
-	struct btrfs_block_group_cache *block_group;
-	struct btrfs_key key;
-	u64 skipped;
-	u64 cur_byte;
-	u64 total_found;
-	u32 nritems;
-	int ret;
-	int progress;
-	int pass = 0;
-
-	root = root->fs_info->extent_root;
-
-	block_group = btrfs_lookup_block_group(info, group_start);
-	BUG_ON(!block_group);
-
-	printk(KERN_INFO "btrfs relocating block group %llu flags %llu\n",
-	       (unsigned long long)block_group->key.objectid,
-	       (unsigned long long)block_group->flags);
-
-	path = btrfs_alloc_path();
-	BUG_ON(!path);
-
-	reloc_inode = create_reloc_inode(info, block_group);
-	BUG_ON(IS_ERR(reloc_inode));
-
-	__alloc_chunk_for_shrink(root, block_group, 1);
-	set_block_group_readonly(block_group);
-
-	btrfs_start_delalloc_inodes(info->tree_root);
-	btrfs_wait_ordered_extents(info->tree_root, 0);
-again:
-	skipped = 0;
-	total_found = 0;
-	progress = 0;
-	key.objectid = block_group->key.objectid;
-	key.offset = 0;
-	key.type = 0;
-	cur_byte = key.objectid;
-
-	trans = btrfs_start_transaction(info->tree_root, 1);
-	btrfs_commit_transaction(trans, info->tree_root);
+	spin_unlock(&space_info->lock);
 
-	mutex_lock(&root->fs_info->cleaner_mutex);
-	btrfs_clean_old_snapshots(info->tree_root);
-	btrfs_remove_leaf_refs(info->tree_root, (u64)-1, 1);
-	mutex_unlock(&root->fs_info->cleaner_mutex);
+	/*
+	 * ok we don't have enough space, but maybe we have free space on our
+	 * devices to allocate new chunks for relocation, so loop through our
+	 * alloc devices and guess if we have enough space.  However, if we
+	 * were marked as full, then we know there aren't enough chunks, and we
+	 * can just return.
+	 */
+	ret = -1;
+	if (full)
+		goto out;
 
-	trans = btrfs_start_transaction(info->tree_root, 1);
-	btrfs_commit_transaction(trans, info->tree_root);
+	mutex_lock(&root->fs_info->chunk_mutex);
+	list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
+		u64 min_free = btrfs_block_group_used(&block_group->item);
+		u64 dev_offset, max_avail;
 
-	while (1) {
-		ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
-		if (ret < 0)
-			goto out;
-next:
-		leaf = path->nodes[0];
-		nritems = btrfs_header_nritems(leaf);
-		if (path->slots[0] >= nritems) {
-			ret = btrfs_next_leaf(root, path);
-			if (ret < 0)
-				goto out;
-			if (ret == 1) {
-				ret = 0;
+		/*
+		 * check to make sure we can actually find a chunk with enough
+		 * space to fit our block group in.
+		 */
+		if (device->total_bytes > device->bytes_used + min_free) {
+			ret = find_free_dev_extent(NULL, device, min_free,
+						   &dev_offset, &max_avail);
+			if (!ret)
 				break;
-			}
-			leaf = path->nodes[0];
-			nritems = btrfs_header_nritems(leaf);
-		}
-
-		btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
-
-		if (key.objectid >= block_group->key.objectid +
-		    block_group->key.offset)
-			break;
-
-		if (progress && need_resched()) {
-			btrfs_release_path(root, path);
-			cond_resched();
-			progress = 0;
-			continue;
-		}
-		progress = 1;
-
-		if (btrfs_key_type(&key) != BTRFS_EXTENT_ITEM_KEY ||
-		    key.objectid + key.offset <= cur_byte) {
-			path->slots[0]++;
-			goto next;
+			ret = -1;
 		}
-
-		total_found++;
-		cur_byte = key.objectid + key.offset;
-		btrfs_release_path(root, path);
-
-		__alloc_chunk_for_shrink(root, block_group, 0);
-		ret = relocate_one_extent(root, path, &key, block_group,
-					  reloc_inode, pass);
-		BUG_ON(ret < 0);
-		if (ret > 0)
-			skipped++;
-
-		key.objectid = cur_byte;
-		key.type = 0;
-		key.offset = 0;
 	}
-
-	btrfs_release_path(root, path);
-
-	if (pass == 0) {
-		btrfs_wait_ordered_range(reloc_inode, 0, (u64)-1);
-		invalidate_mapping_pages(reloc_inode->i_mapping, 0, -1);
-	}
-
-	if (total_found > 0) {
-		printk(KERN_INFO "btrfs found %llu extents in pass %d\n",
-		       (unsigned long long)total_found, pass);
-		pass++;
-		if (total_found == skipped && pass > 2) {
-			iput(reloc_inode);
-			reloc_inode = create_reloc_inode(info, block_group);
-			pass = 0;
-		}
-		goto again;
-	}
-
-	/* delete reloc_inode */
-	iput(reloc_inode);
-
-	/* unpin extents in this range */
-	trans = btrfs_start_transaction(info->tree_root, 1);
-	btrfs_commit_transaction(trans, info->tree_root);
-
-	spin_lock(&block_group->lock);
-	WARN_ON(block_group->pinned > 0);
-	WARN_ON(block_group->reserved > 0);
-	WARN_ON(btrfs_block_group_used(&block_group->item) > 0);
-	spin_unlock(&block_group->lock);
-	btrfs_put_block_group(block_group);
-	ret = 0;
+	mutex_unlock(&root->fs_info->chunk_mutex);
 out:
-	btrfs_free_path(path);
+	btrfs_put_block_group(block_group);
 	return ret;
 }
-#endif
 
 static int find_first_block_group(struct btrfs_root *root,
 		struct btrfs_path *path, struct btrfs_key *key)
@@ -7165,8 +7282,18 @@ int btrfs_free_block_groups(struct btrfs_fs_info *info)
 {
 	struct btrfs_block_group_cache *block_group;
 	struct btrfs_space_info *space_info;
+	struct btrfs_caching_control *caching_ctl;
 	struct rb_node *n;
 
+	down_write(&info->extent_commit_sem);
+	while (!list_empty(&info->caching_block_groups)) {
+		caching_ctl = list_entry(info->caching_block_groups.next,
+					 struct btrfs_caching_control, list);
+		list_del(&caching_ctl->list);
+		put_caching_control(caching_ctl);
+	}
+	up_write(&info->extent_commit_sem);
+
 	spin_lock(&info->block_group_cache_lock);
 	while ((n = rb_last(&info->block_group_cache_tree)) != NULL) {
 		block_group = rb_entry(n, struct btrfs_block_group_cache,
@@ -7180,8 +7307,7 @@ int btrfs_free_block_groups(struct btrfs_fs_info *info)
 		up_write(&block_group->space_info->groups_sem);
 
 		if (block_group->cached == BTRFS_CACHE_STARTED)
-			wait_event(block_group->caching_q,
-				   block_group_cache_done(block_group));
+			wait_block_group_cache_done(block_group);
 
 		btrfs_remove_free_space_cache(block_group);
 
@@ -7251,7 +7377,6 @@ int btrfs_read_block_groups(struct btrfs_root *root)
 		spin_lock_init(&cache->lock);
 		spin_lock_init(&cache->tree_lock);
 		cache->fs_info = info;
-		init_waitqueue_head(&cache->caching_q);
 		INIT_LIST_HEAD(&cache->list);
 		INIT_LIST_HEAD(&cache->cluster_list);
 
@@ -7273,8 +7398,6 @@ int btrfs_read_block_groups(struct btrfs_root *root)
 		cache->flags = btrfs_block_group_flags(&cache->item);
 		cache->sectorsize = root->sectorsize;
 
-		remove_sb_from_cache(root, cache);
-
 		/*
 		 * check for two cases, either we are full, and therefore
 		 * don't need to bother with the caching work since we won't
@@ -7283,13 +7406,19 @@ int btrfs_read_block_groups(struct btrfs_root *root)
 		 * time, particularly in the full case.
 		 */
 		if (found_key.offset == btrfs_block_group_used(&cache->item)) {
+			exclude_super_stripes(root, cache);
+			cache->last_byte_to_unpin = (u64)-1;
 			cache->cached = BTRFS_CACHE_FINISHED;
+			free_excluded_extents(root, cache);
 		} else if (btrfs_block_group_used(&cache->item) == 0) {
+			exclude_super_stripes(root, cache);
+			cache->last_byte_to_unpin = (u64)-1;
 			cache->cached = BTRFS_CACHE_FINISHED;
 			add_new_free_space(cache, root->fs_info,
 					   found_key.objectid,
 					   found_key.objectid +
 					   found_key.offset);
+			free_excluded_extents(root, cache);
 		}
 
 		ret = update_space_info(info, cache->flags, found_key.offset,
@@ -7297,6 +7426,10 @@ int btrfs_read_block_groups(struct btrfs_root *root)
 					&space_info);
 		BUG_ON(ret);
 		cache->space_info = space_info;
+		spin_lock(&cache->space_info->lock);
+		cache->space_info->bytes_super += cache->bytes_super;
+		spin_unlock(&cache->space_info->lock);
+
 		down_write(&space_info->groups_sem);
 		list_add_tail(&cache->list, &space_info->block_groups);
 		up_write(&space_info->groups_sem);
@@ -7346,7 +7479,6 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans,
 	atomic_set(&cache->count, 1);
 	spin_lock_init(&cache->lock);
 	spin_lock_init(&cache->tree_lock);
-	init_waitqueue_head(&cache->caching_q);
 	INIT_LIST_HEAD(&cache->list);
 	INIT_LIST_HEAD(&cache->cluster_list);
 
@@ -7355,15 +7487,23 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans,
 	cache->flags = type;
 	btrfs_set_block_group_flags(&cache->item, type);
 
+	cache->last_byte_to_unpin = (u64)-1;
 	cache->cached = BTRFS_CACHE_FINISHED;
-	remove_sb_from_cache(root, cache);
+	exclude_super_stripes(root, cache);
 
 	add_new_free_space(cache, root->fs_info, chunk_offset,
 			   chunk_offset + size);
 
+	free_excluded_extents(root, cache);
+
 	ret = update_space_info(root->fs_info, cache->flags, size, bytes_used,
 				&cache->space_info);
 	BUG_ON(ret);
+
+	spin_lock(&cache->space_info->lock);
+	cache->space_info->bytes_super += cache->bytes_super;
+	spin_unlock(&cache->space_info->lock);
+
 	down_write(&cache->space_info->groups_sem);
 	list_add_tail(&cache->list, &cache->space_info->block_groups);
 	up_write(&cache->space_info->groups_sem);
@@ -7429,8 +7569,7 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
 	up_write(&block_group->space_info->groups_sem);
 
 	if (block_group->cached == BTRFS_CACHE_STARTED)
-		wait_event(block_group->caching_q,
-			   block_group_cache_done(block_group));
+		wait_block_group_cache_done(block_group);
 
 	btrfs_remove_free_space_cache(block_group);
 
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 6826018..96577e8 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -280,6 +280,14 @@ static struct extent_buffer *buffer_search(struct extent_io_tree *tree,
 	return NULL;
 }
 
+static void merge_cb(struct extent_io_tree *tree, struct extent_state *new,
+		     struct extent_state *other)
+{
+	if (tree->ops && tree->ops->merge_extent_hook)
+		tree->ops->merge_extent_hook(tree->mapping->host, new,
+					     other);
+}
+
 /*
  * utility function to look for merge candidates inside a given range.
  * Any extents with matching state are merged together into a single
@@ -303,6 +311,7 @@ static int merge_state(struct extent_io_tree *tree,
 		other = rb_entry(other_node, struct extent_state, rb_node);
 		if (other->end == state->start - 1 &&
 		    other->state == state->state) {
+			merge_cb(tree, state, other);
 			state->start = other->start;
 			other->tree = NULL;
 			rb_erase(&other->rb_node, &tree->state);
@@ -314,33 +323,37 @@ static int merge_state(struct extent_io_tree *tree,
 		other = rb_entry(other_node, struct extent_state, rb_node);
 		if (other->start == state->end + 1 &&
 		    other->state == state->state) {
+			merge_cb(tree, state, other);
 			other->start = state->start;
 			state->tree = NULL;
 			rb_erase(&state->rb_node, &tree->state);
 			free_extent_state(state);
+			state = NULL;
 		}
 	}
+
 	return 0;
 }
 
-static void set_state_cb(struct extent_io_tree *tree,
+static int set_state_cb(struct extent_io_tree *tree,
 			 struct extent_state *state,
 			 unsigned long bits)
 {
 	if (tree->ops && tree->ops->set_bit_hook) {
-		tree->ops->set_bit_hook(tree->mapping->host, state->start,
-					state->end, state->state, bits);
+		return tree->ops->set_bit_hook(tree->mapping->host,
+					       state->start, state->end,
+					       state->state, bits);
 	}
+
+	return 0;
 }
 
 static void clear_state_cb(struct extent_io_tree *tree,
 			   struct extent_state *state,
 			   unsigned long bits)
 {
-	if (tree->ops && tree->ops->clear_bit_hook) {
-		tree->ops->clear_bit_hook(tree->mapping->host, state->start,
-					  state->end, state->state, bits);
-	}
+	if (tree->ops && tree->ops->clear_bit_hook)
+		tree->ops->clear_bit_hook(tree->mapping->host, state, bits);
 }
 
 /*
@@ -358,6 +371,7 @@ static int insert_state(struct extent_io_tree *tree,
 			int bits)
 {
 	struct rb_node *node;
+	int ret;
 
 	if (end < start) {
 		printk(KERN_ERR "btrfs end < start %llu %llu\n",
@@ -365,12 +379,15 @@ static int insert_state(struct extent_io_tree *tree,
 		       (unsigned long long)start);
 		WARN_ON(1);
 	}
+	state->start = start;
+	state->end = end;
+	ret = set_state_cb(tree, state, bits);
+	if (ret)
+		return ret;
+
 	if (bits & EXTENT_DIRTY)
 		tree->dirty_bytes += end - start + 1;
-	set_state_cb(tree, state, bits);
 	state->state |= bits;
-	state->start = start;
-	state->end = end;
 	node = tree_insert(&tree->state, end, &state->rb_node);
 	if (node) {
 		struct extent_state *found;
@@ -387,6 +404,15 @@ static int insert_state(struct extent_io_tree *tree,
 	return 0;
 }
 
+static int split_cb(struct extent_io_tree *tree, struct extent_state *orig,
+		     u64 split)
+{
+	if (tree->ops && tree->ops->split_extent_hook)
+		return tree->ops->split_extent_hook(tree->mapping->host,
+						    orig, split);
+	return 0;
+}
+
 /*
  * split a given extent state struct in two, inserting the preallocated
  * struct 'prealloc' as the newly created second half.  'split' indicates an
@@ -405,6 +431,9 @@ static int split_state(struct extent_io_tree *tree, struct extent_state *orig,
 		       struct extent_state *prealloc, u64 split)
 {
 	struct rb_node *node;
+
+	split_cb(tree, orig, split);
+
 	prealloc->start = orig->start;
 	prealloc->end = split - 1;
 	prealloc->state = orig->state;
@@ -431,7 +460,8 @@ static int clear_state_bit(struct extent_io_tree *tree,
 			    struct extent_state *state, int bits, int wake,
 			    int delete)
 {
-	int ret = state->state & bits;
+	int bits_to_clear = bits & ~EXTENT_DO_ACCOUNTING;
+	int ret = state->state & bits_to_clear;
 
 	if ((bits & EXTENT_DIRTY) && (state->state & EXTENT_DIRTY)) {
 		u64 range = state->end - state->start + 1;
@@ -439,7 +469,7 @@ static int clear_state_bit(struct extent_io_tree *tree,
 		tree->dirty_bytes -= range;
 	}
 	clear_state_cb(tree, state, bits);
-	state->state &= ~bits;
+	state->state &= ~bits_to_clear;
 	if (wake)
 		wake_up(&state->wq);
 	if (delete || state->state == 0) {
@@ -471,10 +501,14 @@ static int clear_state_bit(struct extent_io_tree *tree,
  * bits were already set, or zero if none of the bits were already set.
  */
 int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
-		     int bits, int wake, int delete, gfp_t mask)
+		     int bits, int wake, int delete,
+		     struct extent_state **cached_state,
+		     gfp_t mask)
 {
 	struct extent_state *state;
+	struct extent_state *cached;
 	struct extent_state *prealloc = NULL;
+	struct rb_node *next_node;
 	struct rb_node *node;
 	u64 last_end;
 	int err;
@@ -488,6 +522,17 @@ again:
 	}
 
 	spin_lock(&tree->lock);
+	if (cached_state) {
+		cached = *cached_state;
+		*cached_state = NULL;
+		cached_state = NULL;
+		if (cached && cached->tree && cached->start == start) {
+			atomic_dec(&cached->refs);
+			state = cached;
+			goto hit_next;
+		}
+		free_extent_state(cached);
+	}
 	/*
 	 * this search will find the extents that end after
 	 * our range starts
@@ -496,6 +541,7 @@ again:
 	if (!node)
 		goto out;
 	state = rb_entry(node, struct extent_state, rb_node);
+hit_next:
 	if (state->start > end)
 		goto out;
 	WARN_ON(state->end < start);
@@ -526,13 +572,11 @@ again:
 		if (err)
 			goto out;
 		if (state->end <= end) {
-			set |= clear_state_bit(tree, state, bits,
-					wake, delete);
+			set |= clear_state_bit(tree, state, bits, wake,
+					       delete);
 			if (last_end == (u64)-1)
 				goto out;
 			start = last_end + 1;
-		} else {
-			start = state->start;
 		}
 		goto search_again;
 	}
@@ -547,19 +591,30 @@ again:
 			prealloc = alloc_extent_state(GFP_ATOMIC);
 		err = split_state(tree, state, prealloc, end + 1);
 		BUG_ON(err == -EEXIST);
-
 		if (wake)
 			wake_up(&state->wq);
-		set |= clear_state_bit(tree, prealloc, bits,
-				       wake, delete);
+
+		set |= clear_state_bit(tree, prealloc, bits, wake, delete);
+
 		prealloc = NULL;
 		goto out;
 	}
 
+	if (state->end < end && prealloc && !need_resched())
+		next_node = rb_next(&state->rb_node);
+	else
+		next_node = NULL;
+
 	set |= clear_state_bit(tree, state, bits, wake, delete);
 	if (last_end == (u64)-1)
 		goto out;
 	start = last_end + 1;
+	if (start <= end && next_node) {
+		state = rb_entry(next_node, struct extent_state,
+				 rb_node);
+		if (state->start == start)
+			goto hit_next;
+	}
 	goto search_again;
 
 out:
@@ -641,40 +696,59 @@ out:
 	return 0;
 }
 
-static void set_state_bits(struct extent_io_tree *tree,
+static int set_state_bits(struct extent_io_tree *tree,
 			   struct extent_state *state,
 			   int bits)
 {
+	int ret;
+
+	ret = set_state_cb(tree, state, bits);
+	if (ret)
+		return ret;
+
 	if ((bits & EXTENT_DIRTY) && !(state->state & EXTENT_DIRTY)) {
 		u64 range = state->end - state->start + 1;
 		tree->dirty_bytes += range;
 	}
-	set_state_cb(tree, state, bits);
 	state->state |= bits;
+
+	return 0;
+}
+
+static void cache_state(struct extent_state *state,
+			struct extent_state **cached_ptr)
+{
+	if (cached_ptr && !(*cached_ptr)) {
+		if (state->state & (EXTENT_IOBITS | EXTENT_BOUNDARY)) {
+			*cached_ptr = state;
+			atomic_inc(&state->refs);
+		}
+	}
 }
 
 /*
- * set some bits on a range in the tree.  This may require allocations
- * or sleeping, so the gfp mask is used to indicate what is allowed.
+ * set some bits on a range in the tree.  This may require allocations or
+ * sleeping, so the gfp mask is used to indicate what is allowed.
  *
- * If 'exclusive' == 1, this will fail with -EEXIST if some part of the
- * range already has the desired bits set.  The start of the existing
- * range is returned in failed_start in this case.
+ * If any of the exclusive bits are set, this will fail with -EEXIST if some
+ * part of the range already has the desired bits set.  The start of the
+ * existing range is returned in failed_start in this case.
  *
- * [start, end] is inclusive
- * This takes the tree lock.
+ * [start, end] is inclusive This takes the tree lock.
  */
+
 static int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
-			  int bits, int exclusive, u64 *failed_start,
+			  int bits, int exclusive_bits, u64 *failed_start,
+			  struct extent_state **cached_state,
 			  gfp_t mask)
 {
 	struct extent_state *state;
 	struct extent_state *prealloc = NULL;
 	struct rb_node *node;
 	int err = 0;
-	int set;
 	u64 last_start;
 	u64 last_end;
+
 again:
 	if (!prealloc && (mask & __GFP_WAIT)) {
 		prealloc = alloc_extent_state(mask);
@@ -683,6 +757,13 @@ again:
 	}
 
 	spin_lock(&tree->lock);
+	if (cached_state && *cached_state) {
+		state = *cached_state;
+		if (state->start == start && state->tree) {
+			node = &state->rb_node;
+			goto hit_next;
+		}
+	}
 	/*
 	 * this search will find all the extents that end after
 	 * our range starts.
@@ -694,8 +775,8 @@ again:
 		BUG_ON(err == -EEXIST);
 		goto out;
 	}
-
 	state = rb_entry(node, struct extent_state, rb_node);
+hit_next:
 	last_start = state->start;
 	last_end = state->end;
 
@@ -706,17 +787,32 @@ again:
 	 * Just lock what we found and keep going
 	 */
 	if (state->start == start && state->end <= end) {
-		set = state->state & bits;
-		if (set && exclusive) {
+		struct rb_node *next_node;
+		if (state->state & exclusive_bits) {
 			*failed_start = state->start;
 			err = -EEXIST;
 			goto out;
 		}
-		set_state_bits(tree, state, bits);
+
+		err = set_state_bits(tree, state, bits);
+		if (err)
+			goto out;
+
+		cache_state(state, cached_state);
 		merge_state(tree, state);
 		if (last_end == (u64)-1)
 			goto out;
+
 		start = last_end + 1;
+		if (start < end && prealloc && !need_resched()) {
+			next_node = rb_next(node);
+			if (next_node) {
+				state = rb_entry(next_node, struct extent_state,
+						 rb_node);
+				if (state->start == start)
+					goto hit_next;
+			}
+		}
 		goto search_again;
 	}
 
@@ -737,8 +833,7 @@ again:
 	 * desired bit on it.
 	 */
 	if (state->start < start) {
-		set = state->state & bits;
-		if (exclusive && set) {
+		if (state->state & exclusive_bits) {
 			*failed_start = start;
 			err = -EEXIST;
 			goto out;
@@ -749,13 +844,14 @@ again:
 		if (err)
 			goto out;
 		if (state->end <= end) {
-			set_state_bits(tree, state, bits);
+			err = set_state_bits(tree, state, bits);
+			if (err)
+				goto out;
+			cache_state(state, cached_state);
 			merge_state(tree, state);
 			if (last_end == (u64)-1)
 				goto out;
 			start = last_end + 1;
-		} else {
-			start = state->start;
 		}
 		goto search_again;
 	}
@@ -774,10 +870,13 @@ again:
 			this_end = last_start - 1;
 		err = insert_state(tree, prealloc, start, this_end,
 				   bits);
-		prealloc = NULL;
 		BUG_ON(err == -EEXIST);
-		if (err)
+		if (err) {
+			prealloc = NULL;
 			goto out;
+		}
+		cache_state(prealloc, cached_state);
+		prealloc = NULL;
 		start = this_end + 1;
 		goto search_again;
 	}
@@ -788,8 +887,7 @@ again:
 	 * on the first half
 	 */
 	if (state->start <= end && state->end > end) {
-		set = state->state & bits;
-		if (exclusive && set) {
+		if (state->state & exclusive_bits) {
 			*failed_start = start;
 			err = -EEXIST;
 			goto out;
@@ -797,7 +895,12 @@ again:
 		err = split_state(tree, state, prealloc, end + 1);
 		BUG_ON(err == -EEXIST);
 
-		set_state_bits(tree, prealloc, bits);
+		err = set_state_bits(tree, prealloc, bits);
+		if (err) {
+			prealloc = NULL;
+			goto out;
+		}
+		cache_state(prealloc, cached_state);
 		merge_state(tree, prealloc);
 		prealloc = NULL;
 		goto out;
@@ -826,86 +929,65 @@ int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
 		     gfp_t mask)
 {
 	return set_extent_bit(tree, start, end, EXTENT_DIRTY, 0, NULL,
-			      mask);
-}
-
-int set_extent_ordered(struct extent_io_tree *tree, u64 start, u64 end,
-		       gfp_t mask)
-{
-	return set_extent_bit(tree, start, end, EXTENT_ORDERED, 0, NULL, mask);
+			      NULL, mask);
 }
 
 int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
 		    int bits, gfp_t mask)
 {
 	return set_extent_bit(tree, start, end, bits, 0, NULL,
-			      mask);
+			      NULL, mask);
 }
 
 int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
 		      int bits, gfp_t mask)
 {
-	return clear_extent_bit(tree, start, end, bits, 0, 0, mask);
+	return clear_extent_bit(tree, start, end, bits, 0, 0, NULL, mask);
 }
 
 int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end,
 		     gfp_t mask)
 {
 	return set_extent_bit(tree, start, end,
-			      EXTENT_DELALLOC | EXTENT_DIRTY,
-			      0, NULL, mask);
+			      EXTENT_DELALLOC | EXTENT_DIRTY | EXTENT_UPTODATE,
+			      0, NULL, NULL, mask);
 }
 
 int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
 		       gfp_t mask)
 {
 	return clear_extent_bit(tree, start, end,
-				EXTENT_DIRTY | EXTENT_DELALLOC, 0, 0, mask);
-}
-
-int clear_extent_ordered(struct extent_io_tree *tree, u64 start, u64 end,
-			 gfp_t mask)
-{
-	return clear_extent_bit(tree, start, end, EXTENT_ORDERED, 1, 0, mask);
+				EXTENT_DIRTY | EXTENT_DELALLOC |
+				EXTENT_DO_ACCOUNTING, 0, 0,
+				NULL, mask);
 }
 
 int set_extent_new(struct extent_io_tree *tree, u64 start, u64 end,
 		     gfp_t mask)
 {
 	return set_extent_bit(tree, start, end, EXTENT_NEW, 0, NULL,
-			      mask);
+			      NULL, mask);
 }
 
 static int clear_extent_new(struct extent_io_tree *tree, u64 start, u64 end,
 		       gfp_t mask)
 {
-	return clear_extent_bit(tree, start, end, EXTENT_NEW, 0, 0, mask);
+	return clear_extent_bit(tree, start, end, EXTENT_NEW, 0, 0,
+				NULL, mask);
 }
 
 int set_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end,
 			gfp_t mask)
 {
 	return set_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, NULL,
-			      mask);
+			      NULL, mask);
 }
 
 static int clear_extent_uptodate(struct extent_io_tree *tree, u64 start,
 				 u64 end, gfp_t mask)
 {
-	return clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0, mask);
-}
-
-static int set_extent_writeback(struct extent_io_tree *tree, u64 start, u64 end,
-			 gfp_t mask)
-{
-	return set_extent_bit(tree, start, end, EXTENT_WRITEBACK,
-			      0, NULL, mask);
-}
-
-static int clear_extent_writeback(struct extent_io_tree *tree, u64 start,
-				  u64 end, gfp_t mask)
-{
-	return clear_extent_bit(tree, start, end, EXTENT_WRITEBACK, 1, 0, mask);
+	return clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0,
+				NULL, mask);
 }
 
 int wait_on_extent_writeback(struct extent_io_tree *tree, u64 start, u64 end)
@@ -917,13 +999,15 @@ int wait_on_extent_writeback(struct extent_io_tree *tree, u64 start, u64 end)
  * either insert or lock state struct between start and end use mask to tell
  * us if waiting is desired.
  */
-int lock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask)
+int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
+		     int bits, struct extent_state **cached_state, gfp_t mask)
 {
 	int err;
 	u64 failed_start;
 	while (1) {
-		err = set_extent_bit(tree, start, end, EXTENT_LOCKED, 1,
-				     &failed_start, mask);
+		err = set_extent_bit(tree, start, end, EXTENT_LOCKED | bits,
+				     EXTENT_LOCKED, &failed_start,
+				     cached_state, mask);
 		if (err == -EEXIST && (mask & __GFP_WAIT)) {
 			wait_extent_bit(tree, failed_start, end, EXTENT_LOCKED);
 			start = failed_start;
@@ -935,27 +1019,40 @@ int lock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask)
 	return err;
 }
 
+int lock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask)
+{
+	return lock_extent_bits(tree, start, end, 0, NULL, mask);
+}
+
 int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end,
 		    gfp_t mask)
 {
 	int err;
 	u64 failed_start;
 
-	err = set_extent_bit(tree, start, end, EXTENT_LOCKED, 1,
-			     &failed_start, mask);
+	err = set_extent_bit(tree, start, end, EXTENT_LOCKED, EXTENT_LOCKED,
+			     &failed_start, NULL, mask);
 	if (err == -EEXIST) {
 		if (failed_start > start)
 			clear_extent_bit(tree, start, failed_start - 1,
-					 EXTENT_LOCKED, 1, 0, mask);
+					 EXTENT_LOCKED, 1, 0, NULL, mask);
 		return 0;
 	}
 	return 1;
 }
 
+int unlock_extent_cached(struct extent_io_tree *tree, u64 start, u64 end,
+			 struct extent_state **cached, gfp_t mask)
+{
+	return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, cached,
+				mask);
+}
+
 int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end,
 		  gfp_t mask)
 {
-	return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, mask);
+	return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, NULL,
+				mask);
 }
 
 /*
@@ -974,7 +1071,6 @@ int set_range_dirty(struct extent_io_tree *tree, u64 start, u64 end)
 		page_cache_release(page);
 		index++;
 	}
-	set_extent_dirty(tree, start, end, GFP_NOFS);
 	return 0;
 }
 
@@ -994,7 +1090,6 @@ static int set_range_writeback(struct extent_io_tree *tree, u64 start, u64 end)
 		page_cache_release(page);
 		index++;
 	}
-	set_extent_writeback(tree, start, end, GFP_NOFS);
 	return 0;
 }
 
@@ -1232,6 +1327,7 @@ static noinline u64 find_lock_delalloc_range(struct inode *inode,
 	u64 delalloc_start;
 	u64 delalloc_end;
 	u64 found;
+	struct extent_state *cached_state = NULL;
 	int ret;
 	int loops = 0;
 
@@ -1269,6 +1365,7 @@ again:
 		/* some of the pages are gone, lets avoid looping by
 		 * shortening the size of the delalloc range we're searching
 		 */
+		free_extent_state(cached_state);
 		if (!loops) {
 			unsigned long offset = (*start) & (PAGE_CACHE_SIZE - 1);
 			max_bytes = PAGE_CACHE_SIZE - offset;
@@ -1282,18 +1379,21 @@ again:
 	BUG_ON(ret);
 
 	/* step three, lock the state bits for the whole range */
-	lock_extent(tree, delalloc_start, delalloc_end, GFP_NOFS);
+	lock_extent_bits(tree, delalloc_start, delalloc_end,
+			 0, &cached_state, GFP_NOFS);
 
 	/* then test to make sure it is all still delalloc */
 	ret = test_range_bit(tree, delalloc_start, delalloc_end,
-			     EXTENT_DELALLOC, 1);
+			     EXTENT_DELALLOC, 1, cached_state);
 	if (!ret) {
-		unlock_extent(tree, delalloc_start, delalloc_end, GFP_NOFS);
+		unlock_extent_cached(tree, delalloc_start, delalloc_end,
+				     &cached_state, GFP_NOFS);
 		__unlock_for_delalloc(inode, locked_page,
 			      delalloc_start, delalloc_end);
 		cond_resched();
 		goto again;
 	}
+	free_extent_state(cached_state);
 	*start = delalloc_start;
 	*end = delalloc_end;
 out_failed:
@@ -1303,11 +1403,7 @@ out_failed:
 int extent_clear_unlock_delalloc(struct inode *inode,
 				struct extent_io_tree *tree,
 				u64 start, u64 end, struct page *locked_page,
-				int unlock_pages,
-				int clear_unlock,
-				int clear_delalloc, int clear_dirty,
-				int set_writeback,
-				int end_writeback)
+				unsigned long op)
 {
 	int ret;
 	struct page *pages[16];
@@ -1317,16 +1413,21 @@ int extent_clear_unlock_delalloc(struct inode *inode,
 	int i;
 	int clear_bits = 0;
 
-	if (clear_unlock)
+	if (op & EXTENT_CLEAR_UNLOCK)
 		clear_bits |= EXTENT_LOCKED;
-	if (clear_dirty)
+	if (op & EXTENT_CLEAR_DIRTY)
 		clear_bits |= EXTENT_DIRTY;
 
-	if (clear_delalloc)
+	if (op & EXTENT_CLEAR_DELALLOC)
 		clear_bits |= EXTENT_DELALLOC;
 
-	clear_extent_bit(tree, start, end, clear_bits, 1, 0, GFP_NOFS);
-	if (!(unlock_pages || clear_dirty || set_writeback || end_writeback))
+	if (op & EXTENT_CLEAR_ACCOUNTING)
+		clear_bits |= EXTENT_DO_ACCOUNTING;
+
+	clear_extent_bit(tree, start, end, clear_bits, 1, 0, NULL, GFP_NOFS);
+	if (!(op & (EXTENT_CLEAR_UNLOCK_PAGE | EXTENT_CLEAR_DIRTY |
+		    EXTENT_SET_WRITEBACK | EXTENT_END_WRITEBACK |
+		    EXTENT_SET_PRIVATE2)))
 		return 0;
 
 	while (nr_pages > 0) {
@@ -1334,17 +1435,21 @@ int extent_clear_unlock_delalloc(struct inode *inode,
 				     min_t(unsigned long,
 				     nr_pages, ARRAY_SIZE(pages)), pages);
 		for (i = 0; i < ret; i++) {
+
+			if (op & EXTENT_SET_PRIVATE2)
+				SetPagePrivate2(pages[i]);
+
 			if (pages[i] == locked_page) {
 				page_cache_release(pages[i]);
 				continue;
 			}
-			if (clear_dirty)
+			if (op & EXTENT_CLEAR_DIRTY)
 				clear_page_dirty_for_io(pages[i]);
-			if (set_writeback)
+			if (op & EXTENT_SET_WRITEBACK)
 				set_page_writeback(pages[i]);
-			if (end_writeback)
+			if (op & EXTENT_END_WRITEBACK)
 				end_page_writeback(pages[i]);
-			if (unlock_pages)
+			if (op & EXTENT_CLEAR_UNLOCK_PAGE)
 				unlock_page(pages[i]);
 			page_cache_release(pages[i]);
 		}
@@ -1476,14 +1581,17 @@ out:
  * range is found set.
  */
 int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
-		   int bits, int filled)
+		   int bits, int filled, struct extent_state *cached)
 {
 	struct extent_state *state = NULL;
 	struct rb_node *node;
 	int bitset = 0;
 
 	spin_lock(&tree->lock);
-	node = tree_search(tree, start);
+	if (cached && cached->tree && cached->start == start)
+		node = &cached->rb_node;
+	else
+		node = tree_search(tree, start);
 	while (node && start <= end) {
 		state = rb_entry(node, struct extent_state, rb_node);
 
@@ -1503,6 +1611,10 @@ int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
 			bitset = 0;
 			break;
 		}
+
+		if (state->end == (u64)-1)
+			break;
+
 		start = state->end + 1;
 		if (start > end)
 			break;
@@ -1526,7 +1638,7 @@ static int check_page_uptodate(struct extent_io_tree *tree,
 {
 	u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
 	u64 end = start + PAGE_CACHE_SIZE - 1;
-	if (test_range_bit(tree, start, end, EXTENT_UPTODATE, 1))
+	if (test_range_bit(tree, start, end, EXTENT_UPTODATE, 1, NULL))
 		SetPageUptodate(page);
 	return 0;
 }
@@ -1540,7 +1652,7 @@ static int check_page_locked(struct extent_io_tree *tree,
 {
 	u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
 	u64 end = start + PAGE_CACHE_SIZE - 1;
-	if (!test_range_bit(tree, start, end, EXTENT_LOCKED, 0))
+	if (!test_range_bit(tree, start, end, EXTENT_LOCKED, 0, NULL))
 		unlock_page(page);
 	return 0;
 }
@@ -1552,10 +1664,7 @@ static int check_page_locked(struct extent_io_tree *tree,
 static int check_page_writeback(struct extent_io_tree *tree,
 			     struct page *page)
 {
-	u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
-	u64 end = start + PAGE_CACHE_SIZE - 1;
-	if (!test_range_bit(tree, start, end, EXTENT_WRITEBACK, 0))
-		end_page_writeback(page);
+	end_page_writeback(page);
 	return 0;
 }
 
@@ -1613,13 +1722,11 @@ static void end_bio_extent_writepage(struct bio *bio, int err)
 		}
 
 		if (!uptodate) {
-			clear_extent_uptodate(tree, start, end, GFP_ATOMIC);
+			clear_extent_uptodate(tree, start, end, GFP_NOFS);
 			ClearPageUptodate(page);
 			SetPageError(page);
 		}
 
-		clear_extent_writeback(tree, start, end, GFP_ATOMIC);
-
 		if (whole_page)
 			end_page_writeback(page);
 		else
@@ -1983,7 +2090,8 @@ static int __extent_read_full_page(struct extent_io_tree *tree,
 			continue;
 		}
 		/* the get_extent function already copied into the page */
-		if (test_range_bit(tree, cur, cur_end, EXTENT_UPTODATE, 1)) {
+		if (test_range_bit(tree, cur, cur_end,
+				   EXTENT_UPTODATE, 1, NULL)) {
 			check_page_uptodate(tree, page);
 			unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS);
 			cur = cur + iosize;
@@ -2078,6 +2186,7 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc,
 	u64 iosize;
 	u64 unlock_start;
 	sector_t sector;
+	struct extent_state *cached_state = NULL;
 	struct extent_map *em;
 	struct block_device *bdev;
 	int ret;
@@ -2124,6 +2233,7 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc,
 	delalloc_end = 0;
 	page_started = 0;
 	if (!epd->extent_locked) {
+		u64 delalloc_to_write = 0;
 		/*
 		 * make sure the wbc mapping index is at least updated
 		 * to this page.
@@ -2143,8 +2253,24 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc,
 			tree->ops->fill_delalloc(inode, page, delalloc_start,
 						 delalloc_end, &page_started,
 						 &nr_written);
+			/*
+			 * delalloc_end is already one less than the total
+			 * length, so we don't subtract one from
+			 * PAGE_CACHE_SIZE
+			 */
+			delalloc_to_write += (delalloc_end - delalloc_start +
+					      PAGE_CACHE_SIZE) >>
+					      PAGE_CACHE_SHIFT;
 			delalloc_start = delalloc_end + 1;
 		}
+		if (wbc->nr_to_write < delalloc_to_write) {
+			int thresh = 8192;
+
+			if (delalloc_to_write < thresh * 2)
+				thresh = delalloc_to_write;
+			wbc->nr_to_write = min_t(u64, delalloc_to_write,
+						 thresh);
+		}
 
 		/* did the fill delalloc function already unlock and start
 		 * the IO?
@@ -2160,15 +2286,10 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc,
 			goto done_unlocked;
 		}
 	}
-	lock_extent(tree, start, page_end, GFP_NOFS);
-
-	unlock_start = start;
-
 	if (tree->ops && tree->ops->writepage_start_hook) {
 		ret = tree->ops->writepage_start_hook(page, start,
 						      page_end);
 		if (ret == -EAGAIN) {
-			unlock_extent(tree, start, page_end, GFP_NOFS);
 			redirty_page_for_writepage(wbc, page);
 			update_nr_written(page, wbc, nr_written);
 			unlock_page(page);
@@ -2184,12 +2305,7 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc,
 	update_nr_written(page, wbc, nr_written + 1);
 
 	end = page_end;
-	if (test_range_bit(tree, start, page_end, EXTENT_DELALLOC, 0))
-		printk(KERN_ERR "btrfs delalloc bits after lock_extent\n");
-
 	if (last_byte <= start) {
-		clear_extent_dirty(tree, start, page_end, GFP_NOFS);
-		unlock_extent(tree, start, page_end, GFP_NOFS);
 		if (tree->ops && tree->ops->writepage_end_io_hook)
 			tree->ops->writepage_end_io_hook(page, start,
 							 page_end, NULL, 1);
@@ -2197,13 +2313,10 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc,
 		goto done;
 	}
 
-	set_extent_uptodate(tree, start, page_end, GFP_NOFS);
 	blocksize = inode->i_sb->s_blocksize;
 
 	while (cur <= end) {
 		if (cur >= last_byte) {
-			clear_extent_dirty(tree, cur, page_end, GFP_NOFS);
-			unlock_extent(tree, unlock_start, page_end, GFP_NOFS);
 			if (tree->ops && tree->ops->writepage_end_io_hook)
 				tree->ops->writepage_end_io_hook(page, cur,
 							 page_end, NULL, 1);
@@ -2235,12 +2348,6 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc,
 		 */
 		if (compressed || block_start == EXTENT_MAP_HOLE ||
 		    block_start == EXTENT_MAP_INLINE) {
-			clear_extent_dirty(tree, cur,
-					   cur + iosize - 1, GFP_NOFS);
-
-			unlock_extent(tree, unlock_start, cur + iosize - 1,
-				      GFP_NOFS);
-
 			/*
 			 * end_io notification does not happen here for
 			 * compressed extents
@@ -2265,13 +2372,12 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc,
 		}
 		/* leave this out until we have a page_mkwrite call */
 		if (0 && !test_range_bit(tree, cur, cur + iosize - 1,
-				   EXTENT_DIRTY, 0)) {
+				   EXTENT_DIRTY, 0, NULL)) {
 			cur = cur + iosize;
 			pg_offset += iosize;
 			continue;
 		}
 
-		clear_extent_dirty(tree, cur, cur + iosize - 1, GFP_NOFS);
 		if (tree->ops && tree->ops->writepage_io_hook) {
 			ret = tree->ops->writepage_io_hook(page, cur,
 						cur + iosize - 1);
@@ -2309,12 +2415,12 @@ done:
 		set_page_writeback(page);
 		end_page_writeback(page);
 	}
-	if (unlock_start <= page_end)
-		unlock_extent(tree, unlock_start, page_end, GFP_NOFS);
 	unlock_page(page);
 
 done_unlocked:
 
+	/* drop our reference on any cached states */
+	free_extent_state(cached_state);
 	return 0;
 }
 
@@ -2339,9 +2445,9 @@ static int extent_write_cache_pages(struct extent_io_tree *tree,
 			     writepage_t writepage, void *data,
 			     void (*flush_fn)(void *))
 {
-	struct backing_dev_info *bdi = mapping->backing_dev_info;
 	int ret = 0;
 	int done = 0;
+	int nr_to_write_done = 0;
 	struct pagevec pvec;
 	int nr_pages;
 	pgoff_t index;
@@ -2361,7 +2467,7 @@ static int extent_write_cache_pages(struct extent_io_tree *tree,
 		scanned = 1;
 	}
 retry:
-	while (!done && (index <= end) &&
+	while (!done && !nr_to_write_done && (index <= end) &&
 	       (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
 			      PAGECACHE_TAG_DIRTY, min(end - index,
 				  (pgoff_t)PAGEVEC_SIZE-1) + 1))) {
@@ -2412,12 +2518,15 @@ retry:
 				unlock_page(page);
 				ret = 0;
 			}
-			if (ret || wbc->nr_to_write <= 0)
-				done = 1;
-			if (wbc->nonblocking && bdi_write_congested(bdi)) {
-				wbc->encountered_congestion = 1;
+			if (ret)
 				done = 1;
-			}
+
+			/*
+			 * the filesystem may choose to bump up nr_to_write.
+			 * We have to make sure to honor the new nr_to_write
+			 * at any time
+			 */
+			nr_to_write_done = wbc->nr_to_write <= 0;
 		}
 		pagevec_release(&pvec);
 		cond_resched();
@@ -2604,10 +2713,11 @@ int extent_invalidatepage(struct extent_io_tree *tree,
 		return 0;
 
 	lock_extent(tree, start, end, GFP_NOFS);
-	wait_on_extent_writeback(tree, start, end);
+	wait_on_page_writeback(page);
 	clear_extent_bit(tree, start, end,
-			 EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC,
-			 1, 1, GFP_NOFS);
+			 EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC |
+			 EXTENT_DO_ACCOUNTING,
+			 1, 1, NULL, GFP_NOFS);
 	return 0;
 }
 
@@ -2687,7 +2797,7 @@ int extent_prepare_write(struct extent_io_tree *tree,
 		    !isnew && !PageUptodate(page) &&
 		    (block_off_end > to || block_off_start < from) &&
 		    !test_range_bit(tree, block_start, cur_end,
-				    EXTENT_UPTODATE, 1)) {
+				    EXTENT_UPTODATE, 1, NULL)) {
 			u64 sector;
 			u64 extent_offset = block_start - em->start;
 			size_t iosize;
@@ -2701,7 +2811,7 @@ int extent_prepare_write(struct extent_io_tree *tree,
 			 */
 			set_extent_bit(tree, block_start,
 				       block_start + iosize - 1,
-				       EXTENT_LOCKED, 0, NULL, GFP_NOFS);
+				       EXTENT_LOCKED, 0, NULL, NULL, GFP_NOFS);
 			ret = submit_extent_page(READ, tree, page,
 					 sector, iosize, page_offset, em->bdev,
 					 NULL, 1,
@@ -2742,13 +2852,18 @@ int try_release_extent_state(struct extent_map_tree *map,
 	int ret = 1;
 
 	if (test_range_bit(tree, start, end,
-			   EXTENT_IOBITS | EXTENT_ORDERED, 0))
+			   EXTENT_IOBITS, 0, NULL))
 		ret = 0;
 	else {
 		if ((mask & GFP_NOFS) == GFP_NOFS)
 			mask = GFP_NOFS;
-		clear_extent_bit(tree, start, end, EXTENT_UPTODATE,
-				 1, 1, mask);
+		/*
+		 * at this point we can safely clear everything except the
+		 * locked bit and the nodatasum bit
+		 */
+		clear_extent_bit(tree, start, end,
+				 ~(EXTENT_LOCKED | EXTENT_NODATASUM),
+				 0, 0, NULL, mask);
 	}
 	return ret;
 }
@@ -2771,29 +2886,28 @@ int try_release_extent_mapping(struct extent_map_tree *map,
 		u64 len;
 		while (start <= end) {
 			len = end - start + 1;
-			spin_lock(&map->lock);
+			write_lock(&map->lock);
 			em = lookup_extent_mapping(map, start, len);
 			if (!em || IS_ERR(em)) {
-				spin_unlock(&map->lock);
+				write_unlock(&map->lock);
 				break;
 			}
 			if (test_bit(EXTENT_FLAG_PINNED, &em->flags) ||
 			    em->start != start) {
-				spin_unlock(&map->lock);
+				write_unlock(&map->lock);
 				free_extent_map(em);
 				break;
 			}
 			if (!test_range_bit(tree, em->start,
 					    extent_map_end(em) - 1,
-					    EXTENT_LOCKED | EXTENT_WRITEBACK |
-					    EXTENT_ORDERED,
-					    0)) {
+					    EXTENT_LOCKED | EXTENT_WRITEBACK,
+					    0, NULL)) {
 				remove_extent_mapping(map, em);
 				/* once for the rb tree */
 				free_extent_map(em);
 			}
 			start = extent_map_end(em);
-			spin_unlock(&map->lock);
+			write_unlock(&map->lock);
 
 			/* once for us */
 			free_extent_map(em);
@@ -3203,7 +3317,7 @@ int extent_range_uptodate(struct extent_io_tree *tree,
 	int uptodate;
 	unsigned long index;
 
-	ret = test_range_bit(tree, start, end, EXTENT_UPTODATE, 1);
+	ret = test_range_bit(tree, start, end, EXTENT_UPTODATE, 1, NULL);
 	if (ret)
 		return 1;
 	while (start <= end) {
@@ -3233,7 +3347,7 @@ int extent_buffer_uptodate(struct extent_io_tree *tree,
 		return 1;
 
 	ret = test_range_bit(tree, eb->start, eb->start + eb->len - 1,
-			   EXTENT_UPTODATE, 1);
+			   EXTENT_UPTODATE, 1, NULL);
 	if (ret)
 		return ret;
 
@@ -3269,7 +3383,7 @@ int read_extent_buffer_pages(struct extent_io_tree *tree,
 		return 0;
 
 	if (test_range_bit(tree, eb->start, eb->start + eb->len - 1,
-			   EXTENT_UPTODATE, 1)) {
+			   EXTENT_UPTODATE, 1, NULL)) {
 		return 0;
 	}
 
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index 5bc20ab..36de250 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -13,10 +13,9 @@
 #define EXTENT_DEFRAG (1 << 6)
 #define EXTENT_DEFRAG_DONE (1 << 7)
 #define EXTENT_BUFFER_FILLED (1 << 8)
-#define EXTENT_ORDERED (1 << 9)
-#define EXTENT_ORDERED_METADATA (1 << 10)
-#define EXTENT_BOUNDARY (1 << 11)
-#define EXTENT_NODATASUM (1 << 12)
+#define EXTENT_BOUNDARY (1 << 9)
+#define EXTENT_NODATASUM (1 << 10)
+#define EXTENT_DO_ACCOUNTING (1 << 11)
 #define EXTENT_IOBITS (EXTENT_LOCKED | EXTENT_WRITEBACK)
 
 /* flags for bio submission */
@@ -27,6 +26,16 @@
 #define EXTENT_BUFFER_BLOCKING 1
 #define EXTENT_BUFFER_DIRTY 2
 
+/* these are flags for extent_clear_unlock_delalloc */
+#define EXTENT_CLEAR_UNLOCK_PAGE 0x1
+#define EXTENT_CLEAR_UNLOCK	 0x2
+#define EXTENT_CLEAR_DELALLOC	 0x4
+#define EXTENT_CLEAR_DIRTY	 0x8
+#define EXTENT_SET_WRITEBACK	 0x10
+#define EXTENT_END_WRITEBACK	 0x20
+#define EXTENT_SET_PRIVATE2	 0x40
+#define EXTENT_CLEAR_ACCOUNTING  0x80
+
 /*
  * page->private values.  Every page that is controlled by the extent
  * map has page->private set to one.
@@ -62,8 +71,13 @@ struct extent_io_ops {
 				      struct extent_state *state, int uptodate);
 	int (*set_bit_hook)(struct inode *inode, u64 start, u64 end,
 			    unsigned long old, unsigned long bits);
-	int (*clear_bit_hook)(struct inode *inode, u64 start, u64 end,
-			    unsigned long old, unsigned long bits);
+	int (*clear_bit_hook)(struct inode *inode, struct extent_state *state,
+			      unsigned long bits);
+	int (*merge_extent_hook)(struct inode *inode,
+				 struct extent_state *new,
+				 struct extent_state *other);
+	int (*split_extent_hook)(struct inode *inode,
+				 struct extent_state *orig, u64 split);
 	int (*write_cache_pages_lock_hook)(struct page *page);
 };
 
@@ -81,10 +95,14 @@ struct extent_state {
 	u64 start;
 	u64 end; /* inclusive */
 	struct rb_node rb_node;
+
+	/* ADD NEW ELEMENTS AFTER THIS */
 	struct extent_io_tree *tree;
 	wait_queue_head_t wq;
 	atomic_t refs;
 	unsigned long state;
+	u64 split_start;
+	u64 split_end;
 
 	/* for use by the FS */
 	u64 private;
@@ -142,6 +160,8 @@ int try_release_extent_state(struct extent_map_tree *map,
 			     struct extent_io_tree *tree, struct page *page,
 			     gfp_t mask);
 int lock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask);
+int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
+		     int bits, struct extent_state **cached, gfp_t mask);
 int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask);
 int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end,
 		    gfp_t mask);
@@ -155,11 +175,12 @@ u64 count_range_bits(struct extent_io_tree *tree,
 		     u64 max_bytes, unsigned long bits);
 
 int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
-		   int bits, int filled);
+		   int bits, int filled, struct extent_state *cached_state);
 int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
 		      int bits, gfp_t mask);
 int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
-		     int bits, int wake, int delete, gfp_t mask);
+		     int bits, int wake, int delete, struct extent_state **cached,
+		     gfp_t mask);
 int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
 		    int bits, gfp_t mask);
 int set_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end,
@@ -278,9 +299,5 @@ int extent_range_uptodate(struct extent_io_tree *tree,
 int extent_clear_unlock_delalloc(struct inode *inode,
 				struct extent_io_tree *tree,
 				u64 start, u64 end, struct page *locked_page,
-				int unlock_page,
-				int clear_unlock,
-				int clear_delalloc, int clear_dirty,
-				int set_writeback,
-				int end_writeback);
+				unsigned long op);
 #endif
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 30c9365..2c726b7 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -36,7 +36,7 @@ void extent_map_exit(void)
 void extent_map_tree_init(struct extent_map_tree *tree, gfp_t mask)
 {
 	tree->map.rb_node = NULL;
-	spin_lock_init(&tree->lock);
+	rwlock_init(&tree->lock);
 }
 
 /**
@@ -198,6 +198,56 @@ static int mergable_maps(struct extent_map *prev, struct extent_map *next)
 	return 0;
 }
 
+int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len)
+{
+	int ret = 0;
+	struct extent_map *merge = NULL;
+	struct rb_node *rb;
+	struct extent_map *em;
+
+	write_lock(&tree->lock);
+	em = lookup_extent_mapping(tree, start, len);
+
+	WARN_ON(em->start != start || !em);
+
+	if (!em)
+		goto out;
+
+	clear_bit(EXTENT_FLAG_PINNED, &em->flags);
+
+	if (em->start != 0) {
+		rb = rb_prev(&em->rb_node);
+		if (rb)
+			merge = rb_entry(rb, struct extent_map, rb_node);
+		if (rb && mergable_maps(merge, em)) {
+			em->start = merge->start;
+			em->len += merge->len;
+			em->block_len += merge->block_len;
+			em->block_start = merge->block_start;
+			merge->in_tree = 0;
+			rb_erase(&merge->rb_node, &tree->map);
+			free_extent_map(merge);
+		}
+	}
+
+	rb = rb_next(&em->rb_node);
+	if (rb)
+		merge = rb_entry(rb, struct extent_map, rb_node);
+	if (rb && mergable_maps(em, merge)) {
+		em->len += merge->len;
+		em->block_len += merge->len;
+		rb_erase(&merge->rb_node, &tree->map);
+		merge->in_tree = 0;
+		free_extent_map(merge);
+	}
+
+	free_extent_map(em);
+out:
+	write_unlock(&tree->lock);
+	return ret;
+
+}
+
 /**
  * add_extent_mapping - add new extent map to the extent tree
  * @tree:	tree to insert new map in
@@ -222,7 +272,6 @@ int add_extent_mapping(struct extent_map_tree *tree,
 		ret = -EEXIST;
 		goto out;
 	}
-	assert_spin_locked(&tree->lock);
 	rb = tree_insert(&tree->map, em->start, &em->rb_node);
 	if (rb) {
 		ret = -EEXIST;
@@ -285,7 +334,6 @@ struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
 	struct rb_node *next = NULL;
 	u64 end = range_end(start, len);
 
-	assert_spin_locked(&tree->lock);
 	rb_node = __tree_search(&tree->map, start, &prev, &next);
 	if (!rb_node && prev) {
 		em = rb_entry(prev, struct extent_map, rb_node);
@@ -319,6 +367,54 @@ out:
 }
 
 /**
+ * search_extent_mapping - find a nearby extent map
+ * @tree:	tree to lookup in
+ * @start:	byte offset to start the search
+ * @len:	length of the lookup range
+ *
+ * Find and return the first extent_map struct in @tree that intersects the
+ * [start, len] range.
+ *
+ * If one can't be found, any nearby extent may be returned
+ */
+struct extent_map *search_extent_mapping(struct extent_map_tree *tree,
+					 u64 start, u64 len)
+{
+	struct extent_map *em;
+	struct rb_node *rb_node;
+	struct rb_node *prev = NULL;
+	struct rb_node *next = NULL;
+
+	rb_node = __tree_search(&tree->map, start, &prev, &next);
+	if (!rb_node && prev) {
+		em = rb_entry(prev, struct extent_map, rb_node);
+		goto found;
+	}
+	if (!rb_node && next) {
+		em = rb_entry(next, struct extent_map, rb_node);
+		goto found;
+	}
+	if (!rb_node) {
+		em = NULL;
+		goto out;
+	}
+	if (IS_ERR(rb_node)) {
+		em = ERR_PTR(PTR_ERR(rb_node));
+		goto out;
+	}
+	em = rb_entry(rb_node, struct extent_map, rb_node);
+	goto found;
+
+	em = NULL;
+	goto out;
+
+found:
+	atomic_inc(&em->refs);
+out:
+	return em;
+}
+
+/**
  * remove_extent_mapping - removes an extent_map from the extent tree
  * @tree:	extent tree to remove from
  * @em:		extent map beeing removed
@@ -331,7 +427,6 @@ int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em)
 	int ret = 0;
 
 	WARN_ON(test_bit(EXTENT_FLAG_PINNED, &em->flags));
-	assert_spin_locked(&tree->lock);
 	rb_erase(&em->rb_node, &tree->map);
 	em->in_tree = 0;
 	return ret;
diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h
index fb6eeef..ab6d74b 100644
--- a/fs/btrfs/extent_map.h
+++ b/fs/btrfs/extent_map.h
@@ -31,7 +31,7 @@ struct extent_map {
 
 struct extent_map_tree {
 	struct rb_root map;
-	spinlock_t lock;
+	rwlock_t lock;
 };
 
 static inline u64 extent_map_end(struct extent_map *em)
@@ -59,4 +59,7 @@ struct extent_map *alloc_extent_map(gfp_t mask);
 void free_extent_map(struct extent_map *em);
 int __init extent_map_init(void);
 void extent_map_exit(void);
+int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len);
+struct extent_map *search_extent_mapping(struct extent_map_tree *tree,
+					 u64 start, u64 len);
 #endif
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 4b83397..06550af 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -112,8 +112,6 @@ static noinline int dirty_and_release_pages(struct btrfs_trans_handle *trans,
 	int err = 0;
 	int i;
 	struct inode *inode = fdentry(file)->d_inode;
-	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
-	u64 hint_byte;
 	u64 num_bytes;
 	u64 start_pos;
 	u64 end_of_last_block;
@@ -125,23 +123,10 @@ static noinline int dirty_and_release_pages(struct btrfs_trans_handle *trans,
 		    root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
 
 	end_of_last_block = start_pos + num_bytes - 1;
+	err = btrfs_set_extent_delalloc(inode, start_pos, end_of_last_block);
+	if (err)
+		return err;
 
-	lock_extent(io_tree, start_pos, end_of_last_block, GFP_NOFS);
-	trans = btrfs_join_transaction(root, 1);
-	if (!trans) {
-		err = -ENOMEM;
-		goto out_unlock;
-	}
-	btrfs_set_trans_block_group(trans, inode);
-	hint_byte = 0;
-
-	set_extent_uptodate(io_tree, start_pos, end_of_last_block, GFP_NOFS);
-
-	/* check for reserved extents on each page, we don't want
-	 * to reset the delalloc bit on things that already have
-	 * extents reserved.
-	 */
-	btrfs_set_extent_delalloc(inode, start_pos, end_of_last_block);
 	for (i = 0; i < num_pages; i++) {
 		struct page *p = pages[i];
 		SetPageUptodate(p);
@@ -155,9 +140,6 @@ static noinline int dirty_and_release_pages(struct btrfs_trans_handle *trans,
 		 * at this time.
 		 */
 	}
-	err = btrfs_end_transaction(trans, root);
-out_unlock:
-	unlock_extent(io_tree, start_pos, end_of_last_block, GFP_NOFS);
 	return err;
 }
 
@@ -189,18 +171,18 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end,
 		if (!split2)
 			split2 = alloc_extent_map(GFP_NOFS);
 
-		spin_lock(&em_tree->lock);
+		write_lock(&em_tree->lock);
 		em = lookup_extent_mapping(em_tree, start, len);
 		if (!em) {
-			spin_unlock(&em_tree->lock);
+			write_unlock(&em_tree->lock);
 			break;
 		}
 		flags = em->flags;
 		if (skip_pinned && test_bit(EXTENT_FLAG_PINNED, &em->flags)) {
-			spin_unlock(&em_tree->lock);
 			if (em->start <= start &&
 			    (!testend || em->start + em->len >= start + len)) {
 				free_extent_map(em);
+				write_unlock(&em_tree->lock);
 				break;
 			}
 			if (start < em->start) {
@@ -210,6 +192,7 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end,
 				start = em->start + em->len;
 			}
 			free_extent_map(em);
+			write_unlock(&em_tree->lock);
 			continue;
 		}
 		compressed = test_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
@@ -260,7 +243,7 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end,
 			free_extent_map(split);
 			split = NULL;
 		}
-		spin_unlock(&em_tree->lock);
+		write_unlock(&em_tree->lock);
 
 		/* once for us */
 		free_extent_map(em);
@@ -289,7 +272,7 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end,
 noinline int btrfs_drop_extents(struct btrfs_trans_handle *trans,
 		       struct btrfs_root *root, struct inode *inode,
 		       u64 start, u64 end, u64 locked_end,
-		       u64 inline_limit, u64 *hint_byte)
+		       u64 inline_limit, u64 *hint_byte, int drop_cache)
 {
 	u64 extent_end = 0;
 	u64 search_start = start;
@@ -314,7 +297,8 @@ noinline int btrfs_drop_extents(struct btrfs_trans_handle *trans,
 	int ret;
 
 	inline_limit = 0;
-	btrfs_drop_extent_cache(inode, start, end - 1, 0);
+	if (drop_cache)
+		btrfs_drop_extent_cache(inode, start, end - 1, 0);
 
 	path = btrfs_alloc_path();
 	if (!path)
@@ -894,7 +878,8 @@ again:
 			btrfs_put_ordered_extent(ordered);
 
 		clear_extent_bits(&BTRFS_I(inode)->io_tree, start_pos,
-				  last_pos - 1, EXTENT_DIRTY | EXTENT_DELALLOC,
+				  last_pos - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
+				  EXTENT_DO_ACCOUNTING,
 				  GFP_NOFS);
 		unlock_extent(&BTRFS_I(inode)->io_tree,
 			      start_pos, last_pos - 1, GFP_NOFS);
@@ -936,21 +921,35 @@ static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
 	start_pos = pos;
 
 	vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
+
+	/* do the reserve before the mutex lock in case we have to do some
+	 * flushing.  We wouldn't deadlock, but this is more polite.
+	 */
+	err = btrfs_reserve_metadata_for_delalloc(root, inode, 1);
+	if (err)
+		goto out_nolock;
+
+	mutex_lock(&inode->i_mutex);
+
 	current->backing_dev_info = inode->i_mapping->backing_dev_info;
 	err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
 	if (err)
-		goto out_nolock;
+		goto out;
+
 	if (count == 0)
-		goto out_nolock;
+		goto out;
 
 	err = file_remove_suid(file);
 	if (err)
-		goto out_nolock;
+		goto out;
+
 	file_update_time(file);
 
 	pages = kmalloc(nrptrs * sizeof(struct page *), GFP_KERNEL);
 
-	mutex_lock(&inode->i_mutex);
+	/* generic_write_checks can change our pos */
+	start_pos = pos;
+
 	BTRFS_I(inode)->sequence++;
 	first_index = pos >> PAGE_CACHE_SHIFT;
 	last_index = (pos + count) >> PAGE_CACHE_SHIFT;
@@ -1024,9 +1023,8 @@ static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
 		}
 
 		if (will_write) {
-			btrfs_fdatawrite_range(inode->i_mapping, pos,
-					       pos + write_bytes - 1,
-					       WB_SYNC_ALL);
+			filemap_fdatawrite_range(inode->i_mapping, pos,
+						 pos + write_bytes - 1);
 		} else {
 			balance_dirty_pages_ratelimited_nr(inode->i_mapping,
 							   num_pages);
@@ -1047,6 +1045,7 @@ out:
 	mutex_unlock(&inode->i_mutex);
 	if (ret)
 		err = ret;
+	btrfs_unreserve_metadata_for_delalloc(root, inode, 1);
 
 out_nolock:
 	kfree(pages);
@@ -1087,8 +1086,10 @@ out_nolock:
 					btrfs_end_transaction(trans, root);
 				else
 					btrfs_commit_transaction(trans, root);
-			} else {
+			} else if (ret != BTRFS_NO_LOG_SYNC) {
 				btrfs_commit_transaction(trans, root);
+			} else {
+				btrfs_end_transaction(trans, root);
 			}
 		}
 		if (file->f_flags & O_DIRECT) {
@@ -1138,6 +1139,13 @@ int btrfs_sync_file(struct file *file, struct dentry *dentry, int datasync)
 	int ret = 0;
 	struct btrfs_trans_handle *trans;
 
+
+	/* we wait first, since the writeback may change the inode */
+	root->log_batch++;
+	/* the VFS called filemap_fdatawrite for us */
+	btrfs_wait_ordered_range(inode, 0, (u64)-1);
+	root->log_batch++;
+
 	/*
 	 * check the transaction that last modified this inode
 	 * and see if its already been committed
@@ -1145,6 +1153,11 @@ int btrfs_sync_file(struct file *file, struct dentry *dentry, int datasync)
 	if (!BTRFS_I(inode)->last_trans)
 		goto out;
 
+	/*
+	 * if the last transaction that changed this file was before
+	 * the current transaction, we can bail out now without any
+	 * syncing
+	 */
 	mutex_lock(&root->fs_info->trans_mutex);
 	if (BTRFS_I(inode)->last_trans <=
 	    root->fs_info->last_trans_committed) {
@@ -1154,13 +1167,6 @@ int btrfs_sync_file(struct file *file, struct dentry *dentry, int datasync)
 	}
 	mutex_unlock(&root->fs_info->trans_mutex);
 
-	root->log_batch++;
-	filemap_fdatawrite(inode->i_mapping);
-	btrfs_wait_ordered_range(inode, 0, (u64)-1);
-	root->log_batch++;
-
-	if (datasync && !(inode->i_state & I_DIRTY_PAGES))
-		goto out;
 	/*
 	 * ok we haven't committed the transaction yet, lets do a commit
 	 */
@@ -1189,21 +1195,25 @@ int btrfs_sync_file(struct file *file, struct dentry *dentry, int datasync)
 	 */
 	mutex_unlock(&dentry->d_inode->i_mutex);
 
-	if (ret > 0) {
-		ret = btrfs_commit_transaction(trans, root);
-	} else {
-		ret = btrfs_sync_log(trans, root);
-		if (ret == 0)
-			ret = btrfs_end_transaction(trans, root);
-		else
+	if (ret != BTRFS_NO_LOG_SYNC) {
+		if (ret > 0) {
 			ret = btrfs_commit_transaction(trans, root);
+		} else {
+			ret = btrfs_sync_log(trans, root);
+			if (ret == 0)
+				ret = btrfs_end_transaction(trans, root);
+			else
+				ret = btrfs_commit_transaction(trans, root);
+		}
+	} else {
+		ret = btrfs_end_transaction(trans, root);
 	}
 	mutex_lock(&dentry->d_inode->i_mutex);
 out:
 	return ret > 0 ? EIO : ret;
 }
 
-static struct vm_operations_struct btrfs_file_vm_ops = {
+static const struct vm_operations_struct btrfs_file_vm_ops = {
 	.fault		= filemap_fault,
 	.page_mkwrite	= btrfs_page_mkwrite,
 };
@@ -1215,7 +1225,7 @@ static int btrfs_file_mmap(struct file	*filp, struct vm_area_struct *vma)
 	return 0;
 }
 
-struct file_operations btrfs_file_operations = {
+const struct file_operations btrfs_file_operations = {
 	.llseek		= generic_file_llseek,
 	.read		= do_sync_read,
 	.aio_read       = generic_file_aio_read,
diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index 5edcee3..5c2caad 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -259,7 +259,9 @@ static int link_free_space(struct btrfs_block_group_cache *block_group,
 
 static void recalculate_thresholds(struct btrfs_block_group_cache *block_group)
 {
-	u64 max_bytes, possible_bytes;
+	u64 max_bytes;
+	u64 bitmap_bytes;
+	u64 extent_bytes;
 
 	/*
 	 * The goal is to keep the total amount of memory used per 1gb of space
@@ -269,22 +271,27 @@ static void recalculate_thresholds(struct btrfs_block_group_cache *block_group)
 	max_bytes = MAX_CACHE_BYTES_PER_GIG *
 		(div64_u64(block_group->key.offset, 1024 * 1024 * 1024));
 
-	possible_bytes = (block_group->total_bitmaps * PAGE_CACHE_SIZE) +
-		(sizeof(struct btrfs_free_space) *
-		 block_group->extents_thresh);
+	/*
+	 * we want to account for 1 more bitmap than what we have so we can make
+	 * sure we don't go over our overall goal of MAX_CACHE_BYTES_PER_GIG as
+	 * we add more bitmaps.
+	 */
+	bitmap_bytes = (block_group->total_bitmaps + 1) * PAGE_CACHE_SIZE;
 
-	if (possible_bytes > max_bytes) {
-		int extent_bytes = max_bytes -
-			(block_group->total_bitmaps * PAGE_CACHE_SIZE);
+	if (bitmap_bytes >= max_bytes) {
+		block_group->extents_thresh = 0;
+		return;
+	}
 
-		if (extent_bytes <= 0) {
-			block_group->extents_thresh = 0;
-			return;
-		}
+	/*
+	 * we want the extent entry threshold to always be at most 1/2 the maxw
+	 * bytes we can have, or whatever is less than that.
+	 */
+	extent_bytes = max_bytes - bitmap_bytes;
+	extent_bytes = min_t(u64, extent_bytes, div64_u64(max_bytes, 2));
 
-		block_group->extents_thresh = extent_bytes /
-			(sizeof(struct btrfs_free_space));
-	}
+	block_group->extents_thresh =
+		div64_u64(extent_bytes, (sizeof(struct btrfs_free_space)));
 }
 
 static void bitmap_clear_bits(struct btrfs_block_group_cache *block_group,
@@ -403,6 +410,7 @@ static void add_new_bitmap(struct btrfs_block_group_cache *block_group,
 	BUG_ON(block_group->total_bitmaps >= max_bitmaps);
 
 	info->offset = offset_to_bitmap(block_group, offset);
+	info->bytes = 0;
 	link_free_space(block_group, info);
 	block_group->total_bitmaps++;
 
diff --git a/fs/btrfs/inode-item.c b/fs/btrfs/inode-item.c
index 6b627c6..72ce3c1 100644
--- a/fs/btrfs/inode-item.c
+++ b/fs/btrfs/inode-item.c
@@ -149,6 +149,8 @@ int btrfs_insert_inode_ref(struct btrfs_trans_handle *trans,
 		ptr = (unsigned long)(ref + 1);
 		ret = 0;
 	} else if (ret < 0) {
+		if (ret == -EOVERFLOW)
+			ret = -EMLINK;
 		goto out;
 	} else {
 		ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
@@ -177,8 +179,6 @@ int btrfs_insert_empty_inode(struct btrfs_trans_handle *trans,
 
 	ret = btrfs_insert_empty_item(trans, root, path, &key,
 				      sizeof(struct btrfs_inode_item));
-	if (ret == 0 && objectid > root->highest_inode)
-		root->highest_inode = objectid;
 	return ret;
 }
 
diff --git a/fs/btrfs/inode-map.c b/fs/btrfs/inode-map.c
index 9abbced..c56eb59 100644
--- a/fs/btrfs/inode-map.c
+++ b/fs/btrfs/inode-map.c
@@ -43,9 +43,10 @@ int btrfs_find_highest_inode(struct btrfs_root *root, u64 *objectid)
 		slot = path->slots[0] - 1;
 		l = path->nodes[0];
 		btrfs_item_key_to_cpu(l, &found_key, slot);
-		*objectid = found_key.objectid;
+		*objectid = max_t(u64, found_key.objectid,
+				  BTRFS_FIRST_FREE_OBJECTID - 1);
 	} else {
-		*objectid = BTRFS_FIRST_FREE_OBJECTID;
+		*objectid = BTRFS_FIRST_FREE_OBJECTID - 1;
 	}
 	ret = 0;
 error:
@@ -53,91 +54,27 @@ error:
 	return ret;
 }
 
-/*
- * walks the btree of allocated inodes and find a hole.
- */
 int btrfs_find_free_objectid(struct btrfs_trans_handle *trans,
 			     struct btrfs_root *root,
 			     u64 dirid, u64 *objectid)
 {
-	struct btrfs_path *path;
-	struct btrfs_key key;
 	int ret;
-	int slot = 0;
-	u64 last_ino = 0;
-	int start_found;
-	struct extent_buffer *l;
-	struct btrfs_key search_key;
-	u64 search_start = dirid;
-
 	mutex_lock(&root->objectid_mutex);
-	if (root->last_inode_alloc >= BTRFS_FIRST_FREE_OBJECTID &&
-	    root->last_inode_alloc < BTRFS_LAST_FREE_OBJECTID) {
-		*objectid = ++root->last_inode_alloc;
-		mutex_unlock(&root->objectid_mutex);
-		return 0;
-	}
-	path = btrfs_alloc_path();
-	BUG_ON(!path);
-	search_start = max(search_start, (u64)BTRFS_FIRST_FREE_OBJECTID);
-	search_key.objectid = search_start;
-	search_key.type = 0;
-	search_key.offset = 0;
-
-	start_found = 0;
-	ret = btrfs_search_slot(trans, root, &search_key, path, 0, 0);
-	if (ret < 0)
-		goto error;
 
-	while (1) {
-		l = path->nodes[0];
-		slot = path->slots[0];
-		if (slot >= btrfs_header_nritems(l)) {
-			ret = btrfs_next_leaf(root, path);
-			if (ret == 0)
-				continue;
-			if (ret < 0)
-				goto error;
-			if (!start_found) {
-				*objectid = search_start;
-				start_found = 1;
-				goto found;
-			}
-			*objectid = last_ino > search_start ?
-				last_ino : search_start;
-			goto found;
-		}
-		btrfs_item_key_to_cpu(l, &key, slot);
-		if (key.objectid >= search_start) {
-			if (start_found) {
-				if (last_ino < search_start)
-					last_ino = search_start;
-				if (key.objectid > last_ino) {
-					*objectid = last_ino;
-					goto found;
-				}
-			} else if (key.objectid > search_start) {
-				*objectid = search_start;
-				goto found;
-			}
-		}
-		if (key.objectid >= BTRFS_LAST_FREE_OBJECTID)
-			break;
+	if (unlikely(root->highest_objectid < BTRFS_FIRST_FREE_OBJECTID)) {
+		ret = btrfs_find_highest_inode(root, &root->highest_objectid);
+		if (ret)
+			goto out;
+	}
 
-		start_found = 1;
-		last_ino = key.objectid + 1;
-		path->slots[0]++;
+	if (unlikely(root->highest_objectid >= BTRFS_LAST_FREE_OBJECTID)) {
+		ret = -ENOSPC;
+		goto out;
 	}
-	BUG_ON(1);
-found:
-	btrfs_release_path(root, path);
-	btrfs_free_path(path);
-	BUG_ON(*objectid < search_start);
-	mutex_unlock(&root->objectid_mutex);
-	return 0;
-error:
-	btrfs_release_path(root, path);
-	btrfs_free_path(path);
+
+	*objectid = ++root->highest_objectid;
+	ret = 0;
+out:
 	mutex_unlock(&root->objectid_mutex);
 	return ret;
 }
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 9096fd0..dae12dc 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -62,7 +62,7 @@ static const struct inode_operations btrfs_special_inode_operations;
 static const struct inode_operations btrfs_file_inode_operations;
 static const struct address_space_operations btrfs_aops;
 static const struct address_space_operations btrfs_symlink_aops;
-static struct file_operations btrfs_dir_file_operations;
+static const struct file_operations btrfs_dir_file_operations;
 static struct extent_io_ops btrfs_extent_io_ops;
 
 static struct kmem_cache *btrfs_inode_cachep;
@@ -231,7 +231,8 @@ static noinline int cow_file_range_inline(struct btrfs_trans_handle *trans,
 	}
 
 	ret = btrfs_drop_extents(trans, root, inode, start,
-				 aligned_end, aligned_end, start, &hint_byte);
+				 aligned_end, aligned_end, start,
+				 &hint_byte, 1);
 	BUG_ON(ret);
 
 	if (isize > actual_end)
@@ -240,7 +241,7 @@ static noinline int cow_file_range_inline(struct btrfs_trans_handle *trans,
 				   inline_len, compressed_size,
 				   compressed_pages);
 	BUG_ON(ret);
-	btrfs_drop_extent_cache(inode, start, aligned_end, 0);
+	btrfs_drop_extent_cache(inode, start, aligned_end - 1, 0);
 	return 0;
 }
 
@@ -423,9 +424,12 @@ again:
 			 * and free up our temp pages.
 			 */
 			extent_clear_unlock_delalloc(inode,
-						     &BTRFS_I(inode)->io_tree,
-						     start, end, NULL, 1, 0,
-						     0, 1, 1, 1);
+			     &BTRFS_I(inode)->io_tree,
+			     start, end, NULL,
+			     EXTENT_CLEAR_UNLOCK_PAGE | EXTENT_CLEAR_DIRTY |
+			     EXTENT_CLEAR_DELALLOC |
+			     EXTENT_CLEAR_ACCOUNTING |
+			     EXTENT_SET_WRITEBACK | EXTENT_END_WRITEBACK);
 			ret = 0;
 			goto free_pages_out;
 		}
@@ -611,9 +615,9 @@ static noinline int submit_compressed_extents(struct inode *inode,
 		set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
 
 		while (1) {
-			spin_lock(&em_tree->lock);
+			write_lock(&em_tree->lock);
 			ret = add_extent_mapping(em_tree, em);
-			spin_unlock(&em_tree->lock);
+			write_unlock(&em_tree->lock);
 			if (ret != -EEXIST) {
 				free_extent_map(em);
 				break;
@@ -636,11 +640,14 @@ static noinline int submit_compressed_extents(struct inode *inode,
 		 * clear dirty, set writeback and unlock the pages.
 		 */
 		extent_clear_unlock_delalloc(inode,
-					     &BTRFS_I(inode)->io_tree,
-					     async_extent->start,
-					     async_extent->start +
-					     async_extent->ram_size - 1,
-					     NULL, 1, 1, 0, 1, 1, 0);
+				&BTRFS_I(inode)->io_tree,
+				async_extent->start,
+				async_extent->start +
+				async_extent->ram_size - 1,
+				NULL, EXTENT_CLEAR_UNLOCK_PAGE |
+				EXTENT_CLEAR_UNLOCK |
+				EXTENT_CLEAR_DELALLOC |
+				EXTENT_CLEAR_DIRTY | EXTENT_SET_WRITEBACK);
 
 		ret = btrfs_submit_compressed_write(inode,
 				    async_extent->start,
@@ -711,9 +718,15 @@ static noinline int cow_file_range(struct inode *inode,
 					    start, end, 0, NULL);
 		if (ret == 0) {
 			extent_clear_unlock_delalloc(inode,
-						     &BTRFS_I(inode)->io_tree,
-						     start, end, NULL, 1, 1,
-						     1, 1, 1, 1);
+				     &BTRFS_I(inode)->io_tree,
+				     start, end, NULL,
+				     EXTENT_CLEAR_UNLOCK_PAGE |
+				     EXTENT_CLEAR_UNLOCK |
+				     EXTENT_CLEAR_DELALLOC |
+				     EXTENT_CLEAR_ACCOUNTING |
+				     EXTENT_CLEAR_DIRTY |
+				     EXTENT_SET_WRITEBACK |
+				     EXTENT_END_WRITEBACK);
 			*nr_written = *nr_written +
 			     (end - start + PAGE_CACHE_SIZE) / PAGE_CACHE_SIZE;
 			*page_started = 1;
@@ -725,9 +738,20 @@ static noinline int cow_file_range(struct inode *inode,
 	BUG_ON(disk_num_bytes >
 	       btrfs_super_total_bytes(&root->fs_info->super_copy));
 
+
+	read_lock(&BTRFS_I(inode)->extent_tree.lock);
+	em = search_extent_mapping(&BTRFS_I(inode)->extent_tree,
+				   start, num_bytes);
+	if (em) {
+		alloc_hint = em->block_start;
+		free_extent_map(em);
+	}
+	read_unlock(&BTRFS_I(inode)->extent_tree.lock);
 	btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0);
 
 	while (disk_num_bytes > 0) {
+		unsigned long op;
+
 		cur_alloc_size = min(disk_num_bytes, root->fs_info->max_extent);
 		ret = btrfs_reserve_extent(trans, root, cur_alloc_size,
 					   root->sectorsize, 0, alloc_hint,
@@ -737,7 +761,6 @@ static noinline int cow_file_range(struct inode *inode,
 		em = alloc_extent_map(GFP_NOFS);
 		em->start = start;
 		em->orig_start = em->start;
-
 		ram_size = ins.offset;
 		em->len = ins.offset;
 
@@ -747,9 +770,9 @@ static noinline int cow_file_range(struct inode *inode,
 		set_bit(EXTENT_FLAG_PINNED, &em->flags);
 
 		while (1) {
-			spin_lock(&em_tree->lock);
+			write_lock(&em_tree->lock);
 			ret = add_extent_mapping(em_tree, em);
-			spin_unlock(&em_tree->lock);
+			write_unlock(&em_tree->lock);
 			if (ret != -EEXIST) {
 				free_extent_map(em);
 				break;
@@ -776,11 +799,17 @@ static noinline int cow_file_range(struct inode *inode,
 		/* we're not doing compressed IO, don't unlock the first
 		 * page (which the caller expects to stay locked), don't
 		 * clear any dirty bits and don't set any writeback bits
+		 *
+		 * Do set the Private2 bit so we know this page was properly
+		 * setup for writepage
 		 */
+		op = unlock ? EXTENT_CLEAR_UNLOCK_PAGE : 0;
+		op |= EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC |
+			EXTENT_SET_PRIVATE2;
+
 		extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
 					     start, start + ram_size - 1,
-					     locked_page, unlock, 1,
-					     1, 0, 0, 0);
+					     locked_page, op);
 		disk_num_bytes -= cur_alloc_size;
 		num_bytes -= cur_alloc_size;
 		alloc_hint = ins.objectid + ins.offset;
@@ -852,8 +881,8 @@ static int cow_file_range_async(struct inode *inode, struct page *locked_page,
 	u64 cur_end;
 	int limit = 10 * 1024 * 1042;
 
-	clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED |
-			 EXTENT_DELALLOC, 1, 0, GFP_NOFS);
+	clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED,
+			 1, 0, NULL, GFP_NOFS);
 	while (start < end) {
 		async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS);
 		async_cow->inode = inode;
@@ -994,6 +1023,7 @@ next_slot:
 
 		if (found_key.offset > cur_offset) {
 			extent_end = found_key.offset;
+			extent_type = 0;
 			goto out_check;
 		}
 
@@ -1080,9 +1110,9 @@ out_check:
 			em->bdev = root->fs_info->fs_devices->latest_bdev;
 			set_bit(EXTENT_FLAG_PINNED, &em->flags);
 			while (1) {
-				spin_lock(&em_tree->lock);
+				write_lock(&em_tree->lock);
 				ret = add_extent_mapping(em_tree, em);
-				spin_unlock(&em_tree->lock);
+				write_unlock(&em_tree->lock);
 				if (ret != -EEXIST) {
 					free_extent_map(em);
 					break;
@@ -1100,8 +1130,10 @@ out_check:
 		BUG_ON(ret);
 
 		extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree,
-					cur_offset, cur_offset + num_bytes - 1,
-					locked_page, 1, 1, 1, 0, 0, 0);
+				cur_offset, cur_offset + num_bytes - 1,
+				locked_page, EXTENT_CLEAR_UNLOCK_PAGE |
+				EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC |
+				EXTENT_SET_PRIVATE2);
 		cur_offset = extent_end;
 		if (cur_offset > end)
 			break;
@@ -1147,6 +1179,89 @@ static int run_delalloc_range(struct inode *inode, struct page *locked_page,
 	return ret;
 }
 
+static int btrfs_split_extent_hook(struct inode *inode,
+				    struct extent_state *orig, u64 split)
+{
+	struct btrfs_root *root = BTRFS_I(inode)->root;
+	u64 size;
+
+	if (!(orig->state & EXTENT_DELALLOC))
+		return 0;
+
+	size = orig->end - orig->start + 1;
+	if (size > root->fs_info->max_extent) {
+		u64 num_extents;
+		u64 new_size;
+
+		new_size = orig->end - split + 1;
+		num_extents = div64_u64(size + root->fs_info->max_extent - 1,
+					root->fs_info->max_extent);
+
+		/*
+		 * if we break a large extent up then leave oustanding_extents
+		 * be, since we've already accounted for the large extent.
+		 */
+		if (div64_u64(new_size + root->fs_info->max_extent - 1,
+			      root->fs_info->max_extent) < num_extents)
+			return 0;
+	}
+
+	spin_lock(&BTRFS_I(inode)->accounting_lock);
+	BTRFS_I(inode)->outstanding_extents++;
+	spin_unlock(&BTRFS_I(inode)->accounting_lock);
+
+	return 0;
+}
+
+/*
+ * extent_io.c merge_extent_hook, used to track merged delayed allocation
+ * extents so we can keep track of new extents that are just merged onto old
+ * extents, such as when we are doing sequential writes, so we can properly
+ * account for the metadata space we'll need.
+ */
+static int btrfs_merge_extent_hook(struct inode *inode,
+				   struct extent_state *new,
+				   struct extent_state *other)
+{
+	struct btrfs_root *root = BTRFS_I(inode)->root;
+	u64 new_size, old_size;
+	u64 num_extents;
+
+	/* not delalloc, ignore it */
+	if (!(other->state & EXTENT_DELALLOC))
+		return 0;
+
+	old_size = other->end - other->start + 1;
+	if (new->start < other->start)
+		new_size = other->end - new->start + 1;
+	else
+		new_size = new->end - other->start + 1;
+
+	/* we're not bigger than the max, unreserve the space and go */
+	if (new_size <= root->fs_info->max_extent) {
+		spin_lock(&BTRFS_I(inode)->accounting_lock);
+		BTRFS_I(inode)->outstanding_extents--;
+		spin_unlock(&BTRFS_I(inode)->accounting_lock);
+		return 0;
+	}
+
+	/*
+	 * If we grew by another max_extent, just return, we want to keep that
+	 * reserved amount.
+	 */
+	num_extents = div64_u64(old_size + root->fs_info->max_extent - 1,
+				root->fs_info->max_extent);
+	if (div64_u64(new_size + root->fs_info->max_extent - 1,
+		      root->fs_info->max_extent) > num_extents)
+		return 0;
+
+	spin_lock(&BTRFS_I(inode)->accounting_lock);
+	BTRFS_I(inode)->outstanding_extents--;
+	spin_unlock(&BTRFS_I(inode)->accounting_lock);
+
+	return 0;
+}
+
 /*
  * extent_io.c set_bit_hook, used to track delayed allocation
  * bytes in this file, and to maintain the list of inodes that
@@ -1155,6 +1270,7 @@ static int run_delalloc_range(struct inode *inode, struct page *locked_page,
 static int btrfs_set_bit_hook(struct inode *inode, u64 start, u64 end,
 		       unsigned long old, unsigned long bits)
 {
+
 	/*
 	 * set_bit and clear bit hooks normally require _irqsave/restore
 	 * but in this case, we are only testeing for the DELALLOC
@@ -1162,6 +1278,10 @@ static int btrfs_set_bit_hook(struct inode *inode, u64 start, u64 end,
 	 */
 	if (!(old & EXTENT_DELALLOC) && (bits & EXTENT_DELALLOC)) {
 		struct btrfs_root *root = BTRFS_I(inode)->root;
+
+		spin_lock(&BTRFS_I(inode)->accounting_lock);
+		BTRFS_I(inode)->outstanding_extents++;
+		spin_unlock(&BTRFS_I(inode)->accounting_lock);
 		btrfs_delalloc_reserve_space(root, inode, end - start + 1);
 		spin_lock(&root->fs_info->delalloc_lock);
 		BTRFS_I(inode)->delalloc_bytes += end - start + 1;
@@ -1178,22 +1298,31 @@ static int btrfs_set_bit_hook(struct inode *inode, u64 start, u64 end,
 /*
  * extent_io.c clear_bit_hook, see set_bit_hook for why
  */
-static int btrfs_clear_bit_hook(struct inode *inode, u64 start, u64 end,
-			 unsigned long old, unsigned long bits)
+static int btrfs_clear_bit_hook(struct inode *inode,
+				struct extent_state *state, unsigned long bits)
 {
 	/*
 	 * set_bit and clear bit hooks normally require _irqsave/restore
 	 * but in this case, we are only testeing for the DELALLOC
 	 * bit, which is only set or cleared with irqs on
 	 */
-	if ((old & EXTENT_DELALLOC) && (bits & EXTENT_DELALLOC)) {
+	if ((state->state & EXTENT_DELALLOC) && (bits & EXTENT_DELALLOC)) {
 		struct btrfs_root *root = BTRFS_I(inode)->root;
 
+		if (bits & EXTENT_DO_ACCOUNTING) {
+			spin_lock(&BTRFS_I(inode)->accounting_lock);
+			BTRFS_I(inode)->outstanding_extents--;
+			spin_unlock(&BTRFS_I(inode)->accounting_lock);
+			btrfs_unreserve_metadata_for_delalloc(root, inode, 1);
+		}
+
 		spin_lock(&root->fs_info->delalloc_lock);
-		if (end - start + 1 > root->fs_info->delalloc_bytes) {
+		if (state->end - state->start + 1 >
+		    root->fs_info->delalloc_bytes) {
 			printk(KERN_INFO "btrfs warning: delalloc account "
 			       "%llu %llu\n",
-			       (unsigned long long)end - start + 1,
+			       (unsigned long long)
+			       state->end - state->start + 1,
 			       (unsigned long long)
 			       root->fs_info->delalloc_bytes);
 			btrfs_delalloc_free_space(root, inode, (u64)-1);
@@ -1201,9 +1330,12 @@ static int btrfs_clear_bit_hook(struct inode *inode, u64 start, u64 end,
 			BTRFS_I(inode)->delalloc_bytes = 0;
 		} else {
 			btrfs_delalloc_free_space(root, inode,
-						  end - start + 1);
-			root->fs_info->delalloc_bytes -= end - start + 1;
-			BTRFS_I(inode)->delalloc_bytes -= end - start + 1;
+						  state->end -
+						  state->start + 1);
+			root->fs_info->delalloc_bytes -= state->end -
+				state->start + 1;
+			BTRFS_I(inode)->delalloc_bytes -= state->end -
+				state->start + 1;
 		}
 		if (BTRFS_I(inode)->delalloc_bytes == 0 &&
 		    !list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
@@ -1374,10 +1506,8 @@ again:
 	lock_extent(&BTRFS_I(inode)->io_tree, page_start, page_end, GFP_NOFS);
 
 	/* already ordered? We're done */
-	if (test_range_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
-			     EXTENT_ORDERED, 0)) {
+	if (PagePrivate2(page))
 		goto out;
-	}
 
 	ordered = btrfs_lookup_ordered_extent(inode, page_start);
 	if (ordered) {
@@ -1413,11 +1543,9 @@ static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end)
 	struct inode *inode = page->mapping->host;
 	struct btrfs_writepage_fixup *fixup;
 	struct btrfs_root *root = BTRFS_I(inode)->root;
-	int ret;
 
-	ret = test_range_bit(&BTRFS_I(inode)->io_tree, start, end,
-			     EXTENT_ORDERED, 0);
-	if (ret)
+	/* this page is properly in the ordered list */
+	if (TestClearPagePrivate2(page))
 		return 0;
 
 	if (PageChecked(page))
@@ -1455,9 +1583,19 @@ static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
 	BUG_ON(!path);
 
 	path->leave_spinning = 1;
+
+	/*
+	 * we may be replacing one extent in the tree with another.
+	 * The new extent is pinned in the extent map, and we don't want
+	 * to drop it from the cache until it is completely in the btree.
+	 *
+	 * So, tell btrfs_drop_extents to leave this extent in the cache.
+	 * the caller is expected to unpin it and allow it to be merged
+	 * with the others.
+	 */
 	ret = btrfs_drop_extents(trans, root, inode, file_pos,
 				 file_pos + num_bytes, locked_end,
-				 file_pos, &hint);
+				 file_pos, &hint, 0);
 	BUG_ON(ret);
 
 	ins.objectid = inode->i_ino;
@@ -1485,7 +1623,6 @@ static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
 	btrfs_mark_buffer_dirty(leaf);
 
 	inode_add_bytes(inode, num_bytes);
-	btrfs_drop_extent_cache(inode, file_pos, file_pos + num_bytes - 1, 0);
 
 	ins.objectid = disk_bytenr;
 	ins.offset = disk_num_bytes;
@@ -1596,6 +1733,9 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
 						ordered_extent->len,
 						compressed, 0, 0,
 						BTRFS_FILE_EXTENT_REG);
+		unpin_extent_cache(&BTRFS_I(inode)->extent_tree,
+				   ordered_extent->file_offset,
+				   ordered_extent->len);
 		BUG_ON(ret);
 	}
 	unlock_extent(io_tree, ordered_extent->file_offset,
@@ -1623,6 +1763,7 @@ nocow:
 static int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end,
 				struct extent_state *state, int uptodate)
 {
+	ClearPagePrivate2(page);
 	return btrfs_finish_ordered_io(page->mapping->host, start, end);
 }
 
@@ -1669,13 +1810,13 @@ static int btrfs_io_failed_hook(struct bio *failed_bio,
 		failrec->last_mirror = 0;
 		failrec->bio_flags = 0;
 
-		spin_lock(&em_tree->lock);
+		read_lock(&em_tree->lock);
 		em = lookup_extent_mapping(em_tree, start, failrec->len);
 		if (em->start > start || em->start + em->len < start) {
 			free_extent_map(em);
 			em = NULL;
 		}
-		spin_unlock(&em_tree->lock);
+		read_unlock(&em_tree->lock);
 
 		if (!em || IS_ERR(em)) {
 			kfree(failrec);
@@ -1794,7 +1935,7 @@ static int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end,
 		return 0;
 
 	if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID &&
-	    test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1)) {
+	    test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1, NULL)) {
 		clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM,
 				  GFP_NOFS);
 		return 0;
@@ -2352,6 +2493,69 @@ static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
 	return ret;
 }
 
+int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
+			struct btrfs_root *root,
+			struct inode *dir, u64 objectid,
+			const char *name, int name_len)
+{
+	struct btrfs_path *path;
+	struct extent_buffer *leaf;
+	struct btrfs_dir_item *di;
+	struct btrfs_key key;
+	u64 index;
+	int ret;
+
+	path = btrfs_alloc_path();
+	if (!path)
+		return -ENOMEM;
+
+	di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
+				   name, name_len, -1);
+	BUG_ON(!di || IS_ERR(di));
+
+	leaf = path->nodes[0];
+	btrfs_dir_item_key_to_cpu(leaf, di, &key);
+	WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid);
+	ret = btrfs_delete_one_dir_name(trans, root, path, di);
+	BUG_ON(ret);
+	btrfs_release_path(root, path);
+
+	ret = btrfs_del_root_ref(trans, root->fs_info->tree_root,
+				 objectid, root->root_key.objectid,
+				 dir->i_ino, &index, name, name_len);
+	if (ret < 0) {
+		BUG_ON(ret != -ENOENT);
+		di = btrfs_search_dir_index_item(root, path, dir->i_ino,
+						 name, name_len);
+		BUG_ON(!di || IS_ERR(di));
+
+		leaf = path->nodes[0];
+		btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
+		btrfs_release_path(root, path);
+		index = key.offset;
+	}
+
+	di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
+					 index, name, name_len, -1);
+	BUG_ON(!di || IS_ERR(di));
+
+	leaf = path->nodes[0];
+	btrfs_dir_item_key_to_cpu(leaf, di, &key);
+	WARN_ON(key.type != BTRFS_ROOT_ITEM_KEY || key.objectid != objectid);
+	ret = btrfs_delete_one_dir_name(trans, root, path, di);
+	BUG_ON(ret);
+	btrfs_release_path(root, path);
+
+	btrfs_i_size_write(dir, dir->i_size - name_len * 2);
+	dir->i_mtime = dir->i_ctime = CURRENT_TIME;
+	ret = btrfs_update_inode(trans, root, dir);
+	BUG_ON(ret);
+	dir->i_sb->s_dirt = 1;
+
+	btrfs_free_path(path);
+	return 0;
+}
+
 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
 {
 	struct inode *inode = dentry->d_inode;
@@ -2361,29 +2565,31 @@ static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
 	struct btrfs_trans_handle *trans;
 	unsigned long nr = 0;
 
-	/*
-	 * the FIRST_FREE_OBJECTID check makes sure we don't try to rmdir
-	 * the root of a subvolume or snapshot
-	 */
 	if (inode->i_size > BTRFS_EMPTY_DIR_SIZE ||
-	    inode->i_ino == BTRFS_FIRST_FREE_OBJECTID) {
+	    inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)
 		return -ENOTEMPTY;
-	}
 
 	trans = btrfs_start_transaction(root, 1);
 	btrfs_set_trans_block_group(trans, dir);
 
+	if (unlikely(inode->i_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
+		err = btrfs_unlink_subvol(trans, root, dir,
+					  BTRFS_I(inode)->location.objectid,
+					  dentry->d_name.name,
+					  dentry->d_name.len);
+		goto out;
+	}
+
 	err = btrfs_orphan_add(trans, inode);
 	if (err)
-		goto fail_trans;
+		goto out;
 
 	/* now the directory is empty */
 	err = btrfs_unlink_inode(trans, root, dir, dentry->d_inode,
 				 dentry->d_name.name, dentry->d_name.len);
 	if (!err)
 		btrfs_i_size_write(inode, 0);
-
-fail_trans:
+out:
 	nr = trans->blocks_used;
 	ret = btrfs_end_transaction_throttle(trans, root);
 	btrfs_btree_balance_dirty(root, nr);
@@ -2826,12 +3032,22 @@ static int btrfs_truncate_page(struct address_space *mapping, loff_t from)
 
 	if ((offset & (blocksize - 1)) == 0)
 		goto out;
+	ret = btrfs_check_data_free_space(root, inode, PAGE_CACHE_SIZE);
+	if (ret)
+		goto out;
+
+	ret = btrfs_reserve_metadata_for_delalloc(root, inode, 1);
+	if (ret)
+		goto out;
 
 	ret = -ENOMEM;
 again:
 	page = grab_cache_page(mapping, index);
-	if (!page)
+	if (!page) {
+		btrfs_free_reserved_data_space(root, inode, PAGE_CACHE_SIZE);
+		btrfs_unreserve_metadata_for_delalloc(root, inode, 1);
 		goto out;
+	}
 
 	page_start = page_offset(page);
 	page_end = page_start + PAGE_CACHE_SIZE - 1;
@@ -2864,7 +3080,16 @@ again:
 		goto again;
 	}
 
-	btrfs_set_extent_delalloc(inode, page_start, page_end);
+	clear_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end,
+			  EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING,
+			  GFP_NOFS);
+
+	ret = btrfs_set_extent_delalloc(inode, page_start, page_end);
+	if (ret) {
+		unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
+		goto out_unlock;
+	}
+
 	ret = 0;
 	if (offset != PAGE_CACHE_SIZE) {
 		kaddr = kmap(page);
@@ -2877,6 +3102,9 @@ again:
 	unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
 
 out_unlock:
+	if (ret)
+		btrfs_free_reserved_data_space(root, inode, PAGE_CACHE_SIZE);
+	btrfs_unreserve_metadata_for_delalloc(root, inode, 1);
 	unlock_page(page);
 	page_cache_release(page);
 out:
@@ -2895,17 +3123,15 @@ int btrfs_cont_expand(struct inode *inode, loff_t size)
 	u64 last_byte;
 	u64 cur_offset;
 	u64 hole_size;
-	int err;
+	int err = 0;
 
 	if (size <= hole_start)
 		return 0;
 
-	err = btrfs_check_metadata_free_space(root);
+	err = btrfs_truncate_page(inode->i_mapping, inode->i_size);
 	if (err)
 		return err;
 
-	btrfs_truncate_page(inode->i_mapping, inode->i_size);
-
 	while (1) {
 		struct btrfs_ordered_extent *ordered;
 		btrfs_wait_ordered_range(inode, hole_start,
@@ -2935,15 +3161,21 @@ int btrfs_cont_expand(struct inode *inode, loff_t size)
 						 cur_offset,
 						 cur_offset + hole_size,
 						 block_end,
-						 cur_offset, &hint_byte);
+						 cur_offset, &hint_byte, 1);
+			if (err)
+				break;
+
+			err = btrfs_reserve_metadata_space(root, 1);
 			if (err)
 				break;
+
 			err = btrfs_insert_file_extent(trans, root,
 					inode->i_ino, cur_offset, 0,
 					0, hole_size, 0, hole_size,
 					0, 0, 0);
 			btrfs_drop_extent_cache(inode, hole_start,
 					last_byte - 1, 0);
+			btrfs_unreserve_metadata_space(root, 1);
 		}
 		free_extent_map(em);
 		cur_offset = last_byte;
@@ -3003,6 +3235,11 @@ void btrfs_delete_inode(struct inode *inode)
 	}
 	btrfs_wait_ordered_range(inode, 0, (u64)-1);
 
+	if (inode->i_nlink > 0) {
+		BUG_ON(btrfs_root_refs(&root->root_item) != 0);
+		goto no_delete;
+	}
+
 	btrfs_i_size_write(inode, 0);
 	trans = btrfs_join_transaction(root, 1);
 
@@ -3070,29 +3307,67 @@ out_err:
  * is kind of like crossing a mount point.
  */
 static int fixup_tree_root_location(struct btrfs_root *root,
-			     struct btrfs_key *location,
-			     struct btrfs_root **sub_root,
-			     struct dentry *dentry)
+				    struct inode *dir,
+				    struct dentry *dentry,
+				    struct btrfs_key *location,
+				    struct btrfs_root **sub_root)
 {
-	struct btrfs_root_item *ri;
+	struct btrfs_path *path;
+	struct btrfs_root *new_root;
+	struct btrfs_root_ref *ref;
+	struct extent_buffer *leaf;
+	int ret;
+	int err = 0;
 
-	if (btrfs_key_type(location) != BTRFS_ROOT_ITEM_KEY)
-		return 0;
-	if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
-		return 0;
+	path = btrfs_alloc_path();
+	if (!path) {
+		err = -ENOMEM;
+		goto out;
+	}
 
-	*sub_root = btrfs_read_fs_root(root->fs_info, location,
-					dentry->d_name.name,
-					dentry->d_name.len);
-	if (IS_ERR(*sub_root))
-		return PTR_ERR(*sub_root);
+	err = -ENOENT;
+	ret = btrfs_find_root_ref(root->fs_info->tree_root, path,
+				  BTRFS_I(dir)->root->root_key.objectid,
+				  location->objectid);
+	if (ret) {
+		if (ret < 0)
+			err = ret;
+		goto out;
+	}
 
-	ri = &(*sub_root)->root_item;
-	location->objectid = btrfs_root_dirid(ri);
-	btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
-	location->offset = 0;
+	leaf = path->nodes[0];
+	ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_root_ref);
+	if (btrfs_root_ref_dirid(leaf, ref) != dir->i_ino ||
+	    btrfs_root_ref_name_len(leaf, ref) != dentry->d_name.len)
+		goto out;
 
-	return 0;
+	ret = memcmp_extent_buffer(leaf, dentry->d_name.name,
+				   (unsigned long)(ref + 1),
+				   dentry->d_name.len);
+	if (ret)
+		goto out;
+
+	btrfs_release_path(root->fs_info->tree_root, path);
+
+	new_root = btrfs_read_fs_root_no_name(root->fs_info, location);
+	if (IS_ERR(new_root)) {
+		err = PTR_ERR(new_root);
+		goto out;
+	}
+
+	if (btrfs_root_refs(&new_root->root_item) == 0) {
+		err = -ENOENT;
+		goto out;
+	}
+
+	*sub_root = new_root;
+	location->objectid = btrfs_root_dirid(&new_root->root_item);
+	location->type = BTRFS_INODE_ITEM_KEY;
+	location->offset = 0;
+	err = 0;
+out:
+	btrfs_free_path(path);
+	return err;
 }
 
 static void inode_tree_add(struct inode *inode)
@@ -3101,11 +3376,13 @@ static void inode_tree_add(struct inode *inode)
 	struct btrfs_inode *entry;
 	struct rb_node **p;
 	struct rb_node *parent;
-
 again:
 	p = &root->inode_tree.rb_node;
 	parent = NULL;
 
+	if (hlist_unhashed(&inode->i_hash))
+		return;
+
 	spin_lock(&root->inode_lock);
 	while (*p) {
 		parent = *p;
@@ -3132,13 +3409,87 @@ again:
 static void inode_tree_del(struct inode *inode)
 {
 	struct btrfs_root *root = BTRFS_I(inode)->root;
+	int empty = 0;
 
 	spin_lock(&root->inode_lock);
 	if (!RB_EMPTY_NODE(&BTRFS_I(inode)->rb_node)) {
 		rb_erase(&BTRFS_I(inode)->rb_node, &root->inode_tree);
 		RB_CLEAR_NODE(&BTRFS_I(inode)->rb_node);
+		empty = RB_EMPTY_ROOT(&root->inode_tree);
 	}
 	spin_unlock(&root->inode_lock);
+
+	if (empty && btrfs_root_refs(&root->root_item) == 0) {
+		synchronize_srcu(&root->fs_info->subvol_srcu);
+		spin_lock(&root->inode_lock);
+		empty = RB_EMPTY_ROOT(&root->inode_tree);
+		spin_unlock(&root->inode_lock);
+		if (empty)
+			btrfs_add_dead_root(root);
+	}
+}
+
+int btrfs_invalidate_inodes(struct btrfs_root *root)
+{
+	struct rb_node *node;
+	struct rb_node *prev;
+	struct btrfs_inode *entry;
+	struct inode *inode;
+	u64 objectid = 0;
+
+	WARN_ON(btrfs_root_refs(&root->root_item) != 0);
+
+	spin_lock(&root->inode_lock);
+again:
+	node = root->inode_tree.rb_node;
+	prev = NULL;
+	while (node) {
+		prev = node;
+		entry = rb_entry(node, struct btrfs_inode, rb_node);
+
+		if (objectid < entry->vfs_inode.i_ino)
+			node = node->rb_left;
+		else if (objectid > entry->vfs_inode.i_ino)
+			node = node->rb_right;
+		else
+			break;
+	}
+	if (!node) {
+		while (prev) {
+			entry = rb_entry(prev, struct btrfs_inode, rb_node);
+			if (objectid <= entry->vfs_inode.i_ino) {
+				node = prev;
+				break;
+			}
+			prev = rb_next(prev);
+		}
+	}
+	while (node) {
+		entry = rb_entry(node, struct btrfs_inode, rb_node);
+		objectid = entry->vfs_inode.i_ino + 1;
+		inode = igrab(&entry->vfs_inode);
+		if (inode) {
+			spin_unlock(&root->inode_lock);
+			if (atomic_read(&inode->i_count) > 1)
+				d_prune_aliases(inode);
+			/*
+			 * btrfs_drop_inode will remove it from
+			 * the inode cache when its usage count
+			 * hits zero.
+			 */
+			iput(inode);
+			cond_resched();
+			spin_lock(&root->inode_lock);
+			goto again;
+		}
+
+		if (cond_resched_lock(&root->inode_lock))
+			goto again;
+
+		node = rb_next(node);
+	}
+	spin_unlock(&root->inode_lock);
+	return 0;
 }
 
 static noinline void init_btrfs_i(struct inode *inode)
@@ -3148,6 +3499,7 @@ static noinline void init_btrfs_i(struct inode *inode)
 	bi->generation = 0;
 	bi->sequence = 0;
 	bi->last_trans = 0;
+	bi->last_sub_trans = 0;
 	bi->logged_trans = 0;
 	bi->delalloc_bytes = 0;
 	bi->reserved_bytes = 0;
@@ -3225,15 +3577,41 @@ struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location,
 	return inode;
 }
 
+static struct inode *new_simple_dir(struct super_block *s,
+				    struct btrfs_key *key,
+				    struct btrfs_root *root)
+{
+	struct inode *inode = new_inode(s);
+
+	if (!inode)
+		return ERR_PTR(-ENOMEM);
+
+	init_btrfs_i(inode);
+
+	BTRFS_I(inode)->root = root;
+	memcpy(&BTRFS_I(inode)->location, key, sizeof(*key));
+	BTRFS_I(inode)->dummy_inode = 1;
+
+	inode->i_ino = BTRFS_EMPTY_SUBVOL_DIR_OBJECTID;
+	inode->i_op = &simple_dir_inode_operations;
+	inode->i_fop = &simple_dir_operations;
+	inode->i_mode = S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO;
+	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
+
+	return inode;
+}
+
 struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
 {
 	struct inode *inode;
-	struct btrfs_inode *bi = BTRFS_I(dir);
-	struct btrfs_root *root = bi->root;
+	struct btrfs_root *root = BTRFS_I(dir)->root;
 	struct btrfs_root *sub_root = root;
 	struct btrfs_key location;
+	int index;
 	int ret;
 
+	dentry->d_op = &btrfs_dentry_operations;
+
 	if (dentry->d_name.len > BTRFS_NAME_LEN)
 		return ERR_PTR(-ENAMETOOLONG);
 
@@ -3242,29 +3620,52 @@ struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
 	if (ret < 0)
 		return ERR_PTR(ret);
 
-	inode = NULL;
-	if (location.objectid) {
-		ret = fixup_tree_root_location(root, &location, &sub_root,
-						dentry);
-		if (ret < 0)
-			return ERR_PTR(ret);
-		if (ret > 0)
-			return ERR_PTR(-ENOENT);
+	if (location.objectid == 0)
+		return NULL;
+
+	if (location.type == BTRFS_INODE_ITEM_KEY) {
+		inode = btrfs_iget(dir->i_sb, &location, root);
+		return inode;
+	}
+
+	BUG_ON(location.type != BTRFS_ROOT_ITEM_KEY);
+
+	index = srcu_read_lock(&root->fs_info->subvol_srcu);
+	ret = fixup_tree_root_location(root, dir, dentry,
+				       &location, &sub_root);
+	if (ret < 0) {
+		if (ret != -ENOENT)
+			inode = ERR_PTR(ret);
+		else
+			inode = new_simple_dir(dir->i_sb, &location, sub_root);
+	} else {
 		inode = btrfs_iget(dir->i_sb, &location, sub_root);
-		if (IS_ERR(inode))
-			return ERR_CAST(inode);
 	}
+	srcu_read_unlock(&root->fs_info->subvol_srcu, index);
+
 	return inode;
 }
 
+static int btrfs_dentry_delete(struct dentry *dentry)
+{
+	struct btrfs_root *root;
+
+	if (!dentry->d_inode && !IS_ROOT(dentry))
+		dentry = dentry->d_parent;
+
+	if (dentry->d_inode) {
+		root = BTRFS_I(dentry->d_inode)->root;
+		if (btrfs_root_refs(&root->root_item) == 0)
+			return 1;
+	}
+	return 0;
+}
+
 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
 				   struct nameidata *nd)
 {
 	struct inode *inode;
 
-	if (dentry->d_name.len > BTRFS_NAME_LEN)
-		return ERR_PTR(-ENAMETOOLONG);
-
 	inode = btrfs_lookup_dentry(dir, dentry);
 	if (IS_ERR(inode))
 		return ERR_CAST(inode);
@@ -3603,9 +4004,6 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
 	if (ret != 0)
 		goto fail;
 
-	if (objectid > root->highest_inode)
-		root->highest_inode = objectid;
-
 	inode->i_uid = current_fsuid();
 
 	if (dir && (dir->i_mode & S_ISGID)) {
@@ -3673,26 +4071,35 @@ int btrfs_add_link(struct btrfs_trans_handle *trans,
 		   struct inode *parent_inode, struct inode *inode,
 		   const char *name, int name_len, int add_backref, u64 index)
 {
-	int ret;
+	int ret = 0;
 	struct btrfs_key key;
 	struct btrfs_root *root = BTRFS_I(parent_inode)->root;
 
-	key.objectid = inode->i_ino;
-	btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
-	key.offset = 0;
+	if (unlikely(inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)) {
+		memcpy(&key, &BTRFS_I(inode)->root->root_key, sizeof(key));
+	} else {
+		key.objectid = inode->i_ino;
+		btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
+		key.offset = 0;
+	}
+
+	if (unlikely(inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)) {
+		ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
+					 key.objectid, root->root_key.objectid,
+					 parent_inode->i_ino,
+					 index, name, name_len);
+	} else if (add_backref) {
+		ret = btrfs_insert_inode_ref(trans, root,
+					     name, name_len, inode->i_ino,
+					     parent_inode->i_ino, index);
+	}
 
-	ret = btrfs_insert_dir_item(trans, root, name, name_len,
-				    parent_inode->i_ino,
-				    &key, btrfs_inode_type(inode),
-				    index);
 	if (ret == 0) {
-		if (add_backref) {
-			ret = btrfs_insert_inode_ref(trans, root,
-						     name, name_len,
-						     inode->i_ino,
-						     parent_inode->i_ino,
-						     index);
-		}
+		ret = btrfs_insert_dir_item(trans, root, name, name_len,
+					    parent_inode->i_ino, &key,
+					    btrfs_inode_type(inode), index);
+		BUG_ON(ret);
+
 		btrfs_i_size_write(parent_inode, parent_inode->i_size +
 				   name_len * 2);
 		parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
@@ -3732,11 +4139,18 @@ static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
 	if (!new_valid_dev(rdev))
 		return -EINVAL;
 
-	err = btrfs_check_metadata_free_space(root);
+	/*
+	 * 2 for inode item and ref
+	 * 2 for dir items
+	 * 1 for xattr if selinux is on
+	 */
+	err = btrfs_reserve_metadata_space(root, 5);
 	if (err)
-		goto fail;
+		return err;
 
 	trans = btrfs_start_transaction(root, 1);
+	if (!trans)
+		goto fail;
 	btrfs_set_trans_block_group(trans, dir);
 
 	err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
@@ -3774,6 +4188,7 @@ out_unlock:
 	nr = trans->blocks_used;
 	btrfs_end_transaction_throttle(trans, root);
 fail:
+	btrfs_unreserve_metadata_space(root, 5);
 	if (drop_inode) {
 		inode_dec_link_count(inode);
 		iput(inode);
@@ -3794,10 +4209,18 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry,
 	u64 objectid;
 	u64 index = 0;
 
-	err = btrfs_check_metadata_free_space(root);
+	/*
+	 * 2 for inode item and ref
+	 * 2 for dir items
+	 * 1 for xattr if selinux is on
+	 */
+	err = btrfs_reserve_metadata_space(root, 5);
 	if (err)
-		goto fail;
+		return err;
+
 	trans = btrfs_start_transaction(root, 1);
+	if (!trans)
+		goto fail;
 	btrfs_set_trans_block_group(trans, dir);
 
 	err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
@@ -3838,6 +4261,7 @@ out_unlock:
 	nr = trans->blocks_used;
 	btrfs_end_transaction_throttle(trans, root);
 fail:
+	btrfs_unreserve_metadata_space(root, 5);
 	if (drop_inode) {
 		inode_dec_link_count(inode);
 		iput(inode);
@@ -3860,10 +4284,16 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
 	if (inode->i_nlink == 0)
 		return -ENOENT;
 
-	btrfs_inc_nlink(inode);
-	err = btrfs_check_metadata_free_space(root);
+	/*
+	 * 1 item for inode ref
+	 * 2 items for dir items
+	 */
+	err = btrfs_reserve_metadata_space(root, 3);
 	if (err)
-		goto fail;
+		return err;
+
+	btrfs_inc_nlink(inode);
+
 	err = btrfs_set_inode_index(dir, &index);
 	if (err)
 		goto fail;
@@ -3875,20 +4305,19 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
 
 	err = btrfs_add_nondir(trans, dentry, inode, 1, index);
 
-	if (err)
-		drop_inode = 1;
-
-	btrfs_update_inode_block_group(trans, dir);
-	err = btrfs_update_inode(trans, root, inode);
-
-	if (err)
+	if (err) {
 		drop_inode = 1;
+	} else {
+		btrfs_update_inode_block_group(trans, dir);
+		err = btrfs_update_inode(trans, root, inode);
+		BUG_ON(err);
+		btrfs_log_new_name(trans, inode, NULL, dentry->d_parent);
+	}
 
 	nr = trans->blocks_used;
-
-	btrfs_log_new_name(trans, inode, NULL, dentry->d_parent);
 	btrfs_end_transaction_throttle(trans, root);
 fail:
+	btrfs_unreserve_metadata_space(root, 3);
 	if (drop_inode) {
 		inode_dec_link_count(inode);
 		iput(inode);
@@ -3908,17 +4337,21 @@ static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 	u64 index = 0;
 	unsigned long nr = 1;
 
-	err = btrfs_check_metadata_free_space(root);
+	/*
+	 * 2 items for inode and ref
+	 * 2 items for dir items
+	 * 1 for xattr if selinux is on
+	 */
+	err = btrfs_reserve_metadata_space(root, 5);
 	if (err)
-		goto out_unlock;
+		return err;
 
 	trans = btrfs_start_transaction(root, 1);
-	btrfs_set_trans_block_group(trans, dir);
-
-	if (IS_ERR(trans)) {
-		err = PTR_ERR(trans);
+	if (!trans) {
+		err = -ENOMEM;
 		goto out_unlock;
 	}
+	btrfs_set_trans_block_group(trans, dir);
 
 	err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
 	if (err) {
@@ -3967,6 +4400,7 @@ out_fail:
 	btrfs_end_transaction_throttle(trans, root);
 
 out_unlock:
+	btrfs_unreserve_metadata_space(root, 5);
 	if (drop_on_err)
 		iput(inode);
 	btrfs_btree_balance_dirty(root, nr);
@@ -4064,11 +4498,11 @@ struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
 	int compressed;
 
 again:
-	spin_lock(&em_tree->lock);
+	read_lock(&em_tree->lock);
 	em = lookup_extent_mapping(em_tree, start, len);
 	if (em)
 		em->bdev = root->fs_info->fs_devices->latest_bdev;
-	spin_unlock(&em_tree->lock);
+	read_unlock(&em_tree->lock);
 
 	if (em) {
 		if (em->start > start || em->start + em->len <= start)
@@ -4215,6 +4649,11 @@ again:
 				map = kmap(page);
 				read_extent_buffer(leaf, map + pg_offset, ptr,
 						   copy_size);
+				if (pg_offset + copy_size < PAGE_CACHE_SIZE) {
+					memset(map + pg_offset + copy_size, 0,
+					       PAGE_CACHE_SIZE - pg_offset -
+					       copy_size);
+				}
 				kunmap(page);
 			}
 			flush_dcache_page(page);
@@ -4259,7 +4698,7 @@ insert:
 	}
 
 	err = 0;
-	spin_lock(&em_tree->lock);
+	write_lock(&em_tree->lock);
 	ret = add_extent_mapping(em_tree, em);
 	/* it is possible that someone inserted the extent into the tree
 	 * while we had the lock dropped.  It is also possible that
@@ -4299,7 +4738,7 @@ insert:
 			err = 0;
 		}
 	}
-	spin_unlock(&em_tree->lock);
+	write_unlock(&em_tree->lock);
 out:
 	if (path)
 		btrfs_free_path(path);
@@ -4398,13 +4837,21 @@ static void btrfs_invalidatepage(struct page *page, unsigned long offset)
 	u64 page_start = page_offset(page);
 	u64 page_end = page_start + PAGE_CACHE_SIZE - 1;
 
+
+	/*
+	 * we have the page locked, so new writeback can't start,
+	 * and the dirty bit won't be cleared while we are here.
+	 *
+	 * Wait for IO on this page so that we can safely clear
+	 * the PagePrivate2 bit and do ordered accounting
+	 */
 	wait_on_page_writeback(page);
+
 	tree = &BTRFS_I(page->mapping->host)->io_tree;
 	if (offset) {
 		btrfs_releasepage(page, GFP_NOFS);
 		return;
 	}
-
 	lock_extent(tree, page_start, page_end, GFP_NOFS);
 	ordered = btrfs_lookup_ordered_extent(page->mapping->host,
 					   page_offset(page));
@@ -4415,16 +4862,22 @@ static void btrfs_invalidatepage(struct page *page, unsigned long offset)
 		 */
 		clear_extent_bit(tree, page_start, page_end,
 				 EXTENT_DIRTY | EXTENT_DELALLOC |
-				 EXTENT_LOCKED, 1, 0, GFP_NOFS);
-		btrfs_finish_ordered_io(page->mapping->host,
-					page_start, page_end);
+				 EXTENT_LOCKED | EXTENT_DO_ACCOUNTING, 1, 0,
+				 NULL, GFP_NOFS);
+		/*
+		 * whoever cleared the private bit is responsible
+		 * for the finish_ordered_io
+		 */
+		if (TestClearPagePrivate2(page)) {
+			btrfs_finish_ordered_io(page->mapping->host,
+						page_start, page_end);
+		}
 		btrfs_put_ordered_extent(ordered);
 		lock_extent(tree, page_start, page_end, GFP_NOFS);
 	}
 	clear_extent_bit(tree, page_start, page_end,
 		 EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC |
-		 EXTENT_ORDERED,
-		 1, 1, GFP_NOFS);
+		 EXTENT_DO_ACCOUNTING, 1, 1, NULL, GFP_NOFS);
 	__btrfs_releasepage(page, GFP_NOFS);
 
 	ClearPageChecked(page);
@@ -4473,6 +4926,13 @@ int btrfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
 		goto out;
 	}
 
+	ret = btrfs_reserve_metadata_for_delalloc(root, inode, 1);
+	if (ret) {
+		btrfs_free_reserved_data_space(root, inode, PAGE_CACHE_SIZE);
+		ret = VM_FAULT_SIGBUS;
+		goto out;
+	}
+
 	ret = VM_FAULT_NOPAGE; /* make the VM retry the fault */
 again:
 	lock_page(page);
@@ -4504,7 +4964,24 @@ again:
 		goto again;
 	}
 
-	btrfs_set_extent_delalloc(inode, page_start, page_end);
+	/*
+	 * XXX - page_mkwrite gets called every time the page is dirtied, even
+	 * if it was already dirty, so for space accounting reasons we need to
+	 * clear any delalloc bits for the range we are fixing to save.  There
+	 * is probably a better way to do this, but for now keep consistent with
+	 * prepare_pages in the normal write path.
+	 */
+	clear_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end,
+			  EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING,
+			  GFP_NOFS);
+
+	ret = btrfs_set_extent_delalloc(inode, page_start, page_end);
+	if (ret) {
+		unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
+		ret = VM_FAULT_SIGBUS;
+		btrfs_free_reserved_data_space(root, inode, PAGE_CACHE_SIZE);
+		goto out_unlock;
+	}
 	ret = 0;
 
 	/* page is wholly or partially inside EOF */
@@ -4521,11 +4998,17 @@ again:
 	}
 	ClearPageChecked(page);
 	set_page_dirty(page);
+	SetPageUptodate(page);
+
+	BTRFS_I(inode)->last_trans = root->fs_info->generation;
+	BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid;
 
-	BTRFS_I(inode)->last_trans = root->fs_info->generation + 1;
 	unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
 
 out_unlock:
+	btrfs_unreserve_metadata_for_delalloc(root, inode, 1);
+	if (!ret)
+		return VM_FAULT_LOCKED;
 	unlock_page(page);
 out:
 	return ret;
@@ -4544,7 +5027,9 @@ static void btrfs_truncate(struct inode *inode)
 	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
 		return;
 
-	btrfs_truncate_page(inode->i_mapping, inode->i_size);
+	ret = btrfs_truncate_page(inode->i_mapping, inode->i_size);
+	if (ret)
+		return;
 	btrfs_wait_ordered_range(inode, inode->i_size & (~mask), (u64)-1);
 
 	trans = btrfs_start_transaction(root, 1);
@@ -4594,11 +5079,11 @@ out:
  * create a new subvolume directory/inode (helper for the ioctl).
  */
 int btrfs_create_subvol_root(struct btrfs_trans_handle *trans,
-			     struct btrfs_root *new_root, struct dentry *dentry,
+			     struct btrfs_root *new_root,
 			     u64 new_dirid, u64 alloc_hint)
 {
 	struct inode *inode;
-	int error;
+	int err;
 	u64 index = 0;
 
 	inode = btrfs_new_inode(trans, new_root, NULL, "..", 2, new_dirid,
@@ -4611,11 +5096,10 @@ int btrfs_create_subvol_root(struct btrfs_trans_handle *trans,
 	inode->i_nlink = 1;
 	btrfs_i_size_write(inode, 0);
 
-	error = btrfs_update_inode(trans, new_root, inode);
-	if (error)
-		return error;
+	err = btrfs_update_inode(trans, new_root, inode);
+	BUG_ON(err);
 
-	d_instantiate(dentry, inode);
+	iput(inode);
 	return 0;
 }
 
@@ -4640,7 +5124,11 @@ struct inode *btrfs_alloc_inode(struct super_block *sb)
 	if (!ei)
 		return NULL;
 	ei->last_trans = 0;
+	ei->last_sub_trans = 0;
 	ei->logged_trans = 0;
+	ei->outstanding_extents = 0;
+	ei->reserved_extents = 0;
+	spin_lock_init(&ei->accounting_lock);
 	btrfs_ordered_inode_tree_init(&ei->ordered_tree);
 	INIT_LIST_HEAD(&ei->i_orphan);
 	INIT_LIST_HEAD(&ei->ordered_operations);
@@ -4693,6 +5181,16 @@ void btrfs_destroy_inode(struct inode *inode)
 	kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
 }
 
+void btrfs_drop_inode(struct inode *inode)
+{
+	struct btrfs_root *root = BTRFS_I(inode)->root;
+
+	if (inode->i_nlink > 0 && btrfs_root_refs(&root->root_item) == 0)
+		generic_delete_inode(inode);
+	else
+		generic_drop_inode(inode);
+}
+
 static void init_once(void *foo)
 {
 	struct btrfs_inode *ei = (struct btrfs_inode *) foo;
@@ -4761,31 +5259,37 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 {
 	struct btrfs_trans_handle *trans;
 	struct btrfs_root *root = BTRFS_I(old_dir)->root;
+	struct btrfs_root *dest = BTRFS_I(new_dir)->root;
 	struct inode *new_inode = new_dentry->d_inode;
 	struct inode *old_inode = old_dentry->d_inode;
 	struct timespec ctime = CURRENT_TIME;
 	u64 index = 0;
+	u64 root_objectid;
 	int ret;
 
-	/* we're not allowed to rename between subvolumes */
-	if (BTRFS_I(old_inode)->root->root_key.objectid !=
-	    BTRFS_I(new_dir)->root->root_key.objectid)
+	if (new_dir->i_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)
+		return -EPERM;
+
+	/* we only allow rename subvolume link between subvolumes */
+	if (old_inode->i_ino != BTRFS_FIRST_FREE_OBJECTID && root != dest)
 		return -EXDEV;
 
+	if (old_inode->i_ino == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID ||
+	    (new_inode && new_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID))
+		return -ENOTEMPTY;
+
 	if (S_ISDIR(old_inode->i_mode) && new_inode &&
-	    new_inode->i_size > BTRFS_EMPTY_DIR_SIZE) {
+	    new_inode->i_size > BTRFS_EMPTY_DIR_SIZE)
 		return -ENOTEMPTY;
-	}
 
-	/* to rename a snapshot or subvolume, we need to juggle the
-	 * backrefs.  This isn't coded yet
+	/*
+	 * 2 items for dir items
+	 * 1 item for orphan entry
+	 * 1 item for ref
 	 */
-	if (old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)
-		return -EXDEV;
-
-	ret = btrfs_check_metadata_free_space(root);
+	ret = btrfs_reserve_metadata_space(root, 4);
 	if (ret)
-		goto out_unlock;
+		return ret;
 
 	/*
 	 * we're using rename to replace one file with another.
@@ -4796,8 +5300,40 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 	    old_inode->i_size > BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT)
 		filemap_flush(old_inode->i_mapping);
 
+	/* close the racy window with snapshot create/destroy ioctl */
+	if (old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)
+		down_read(&root->fs_info->subvol_sem);
+
 	trans = btrfs_start_transaction(root, 1);
+	btrfs_set_trans_block_group(trans, new_dir);
+
+	if (dest != root)
+		btrfs_record_root_in_trans(trans, dest);
 
+	ret = btrfs_set_inode_index(new_dir, &index);
+	if (ret)
+		goto out_fail;
+
+	if (unlikely(old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)) {
+		/* force full log commit if subvolume involved. */
+		root->fs_info->last_trans_log_full_commit = trans->transid;
+	} else {
+		ret = btrfs_insert_inode_ref(trans, dest,
+					     new_dentry->d_name.name,
+					     new_dentry->d_name.len,
+					     old_inode->i_ino,
+					     new_dir->i_ino, index);
+		if (ret)
+			goto out_fail;
+		/*
+		 * this is an ugly little race, but the rename is required
+		 * to make sure that if we crash, the inode is either at the
+		 * old name or the new one.  pinning the log transaction lets
+		 * us make sure we don't allow a log commit to come in after
+		 * we unlink the name but before we add the new name back in.
+		 */
+		btrfs_pin_log_trans(root);
+	}
 	/*
 	 * make sure the inode gets flushed if it is replacing
 	 * something.
@@ -4807,18 +5343,6 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 		btrfs_add_ordered_operation(trans, root, old_inode);
 	}
 
-	/*
-	 * this is an ugly little race, but the rename is required to make
-	 * sure that if we crash, the inode is either at the old name
-	 * or the new one.  pinning the log transaction lets us make sure
-	 * we don't allow a log commit to come in after we unlink the
-	 * name but before we add the new name back in.
-	 */
-	btrfs_pin_log_trans(root);
-
-	btrfs_set_trans_block_group(trans, new_dir);
-
-	btrfs_inc_nlink(old_dentry->d_inode);
 	old_dir->i_ctime = old_dir->i_mtime = ctime;
 	new_dir->i_ctime = new_dir->i_mtime = ctime;
 	old_inode->i_ctime = ctime;
@@ -4826,47 +5350,60 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 	if (old_dentry->d_parent != new_dentry->d_parent)
 		btrfs_record_unlink_dir(trans, old_dir, old_inode, 1);
 
-	ret = btrfs_unlink_inode(trans, root, old_dir, old_dentry->d_inode,
-				 old_dentry->d_name.name,
-				 old_dentry->d_name.len);
-	if (ret)
-		goto out_fail;
+	if (unlikely(old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)) {
+		root_objectid = BTRFS_I(old_inode)->root->root_key.objectid;
+		ret = btrfs_unlink_subvol(trans, root, old_dir, root_objectid,
+					old_dentry->d_name.name,
+					old_dentry->d_name.len);
+	} else {
+		btrfs_inc_nlink(old_dentry->d_inode);
+		ret = btrfs_unlink_inode(trans, root, old_dir,
+					 old_dentry->d_inode,
+					 old_dentry->d_name.name,
+					 old_dentry->d_name.len);
+	}
+	BUG_ON(ret);
 
 	if (new_inode) {
 		new_inode->i_ctime = CURRENT_TIME;
-		ret = btrfs_unlink_inode(trans, root, new_dir,
-					 new_dentry->d_inode,
-					 new_dentry->d_name.name,
-					 new_dentry->d_name.len);
-		if (ret)
-			goto out_fail;
+		if (unlikely(new_inode->i_ino ==
+			     BTRFS_EMPTY_SUBVOL_DIR_OBJECTID)) {
+			root_objectid = BTRFS_I(new_inode)->location.objectid;
+			ret = btrfs_unlink_subvol(trans, dest, new_dir,
+						root_objectid,
+						new_dentry->d_name.name,
+						new_dentry->d_name.len);
+			BUG_ON(new_inode->i_nlink == 0);
+		} else {
+			ret = btrfs_unlink_inode(trans, dest, new_dir,
+						 new_dentry->d_inode,
+						 new_dentry->d_name.name,
+						 new_dentry->d_name.len);
+		}
+		BUG_ON(ret);
 		if (new_inode->i_nlink == 0) {
 			ret = btrfs_orphan_add(trans, new_dentry->d_inode);
-			if (ret)
-				goto out_fail;
+			BUG_ON(ret);
 		}
-
 	}
-	ret = btrfs_set_inode_index(new_dir, &index);
-	if (ret)
-		goto out_fail;
 
-	ret = btrfs_add_link(trans, new_dentry->d_parent->d_inode,
-			     old_inode, new_dentry->d_name.name,
-			     new_dentry->d_name.len, 1, index);
-	if (ret)
-		goto out_fail;
+	ret = btrfs_add_link(trans, new_dir, old_inode,
+			     new_dentry->d_name.name,
+			     new_dentry->d_name.len, 0, index);
+	BUG_ON(ret);
 
-	btrfs_log_new_name(trans, old_inode, old_dir,
-				       new_dentry->d_parent);
+	if (old_inode->i_ino != BTRFS_FIRST_FREE_OBJECTID) {
+		btrfs_log_new_name(trans, old_inode, old_dir,
+				   new_dentry->d_parent);
+		btrfs_end_log_trans(root);
+	}
 out_fail:
-
-	/* this btrfs_end_log_trans just allows the current
-	 * log-sub transaction to complete
-	 */
-	btrfs_end_log_trans(root);
 	btrfs_end_transaction_throttle(trans, root);
-out_unlock:
+
+	if (old_inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)
+		up_read(&root->fs_info->subvol_sem);
+
+	btrfs_unreserve_metadata_space(root, 4);
 	return ret;
 }
 
@@ -4938,11 +5475,18 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
 	if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
 		return -ENAMETOOLONG;
 
-	err = btrfs_check_metadata_free_space(root);
+	/*
+	 * 2 items for inode item and ref
+	 * 2 items for dir items
+	 * 1 item for xattr if selinux is on
+	 */
+	err = btrfs_reserve_metadata_space(root, 5);
 	if (err)
-		goto out_fail;
+		return err;
 
 	trans = btrfs_start_transaction(root, 1);
+	if (!trans)
+		goto out_fail;
 	btrfs_set_trans_block_group(trans, dir);
 
 	err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
@@ -5023,6 +5567,7 @@ out_unlock:
 	nr = trans->blocks_used;
 	btrfs_end_transaction_throttle(trans, root);
 out_fail:
+	btrfs_unreserve_metadata_space(root, 5);
 	if (drop_inode) {
 		inode_dec_link_count(inode);
 		iput(inode);
@@ -5044,6 +5589,11 @@ static int prealloc_file_range(struct btrfs_trans_handle *trans,
 
 	while (num_bytes > 0) {
 		alloc_size = min(num_bytes, root->fs_info->max_extent);
+
+		ret = btrfs_reserve_metadata_space(root, 1);
+		if (ret)
+			goto out;
+
 		ret = btrfs_reserve_extent(trans, root, alloc_size,
 					   root->sectorsize, 0, alloc_hint,
 					   (u64)-1, &ins, 1);
@@ -5058,9 +5608,12 @@ static int prealloc_file_range(struct btrfs_trans_handle *trans,
 						  0, 0, 0,
 						  BTRFS_FILE_EXTENT_PREALLOC);
 		BUG_ON(ret);
+		btrfs_drop_extent_cache(inode, cur_offset,
+					cur_offset + ins.offset -1, 0);
 		num_bytes -= ins.offset;
 		cur_offset += ins.offset;
 		alloc_hint = ins.objectid + ins.offset;
+		btrfs_unreserve_metadata_space(root, 1);
 	}
 out:
 	if (cur_offset > start) {
@@ -5223,7 +5776,8 @@ static const struct inode_operations btrfs_dir_ro_inode_operations = {
 	.lookup		= btrfs_lookup,
 	.permission	= btrfs_permission,
 };
-static struct file_operations btrfs_dir_file_operations = {
+
+static const struct file_operations btrfs_dir_file_operations = {
 	.llseek		= generic_file_llseek,
 	.read		= generic_read_dir,
 	.readdir	= btrfs_real_readdir,
@@ -5245,6 +5799,8 @@ static struct extent_io_ops btrfs_extent_io_ops = {
 	.readpage_io_failed_hook = btrfs_io_failed_hook,
 	.set_bit_hook = btrfs_set_bit_hook,
 	.clear_bit_hook = btrfs_clear_bit_hook,
+	.merge_extent_hook = btrfs_merge_extent_hook,
+	.split_extent_hook = btrfs_split_extent_hook,
 };
 
 /*
@@ -5269,6 +5825,7 @@ static const struct address_space_operations btrfs_aops = {
 	.invalidatepage = btrfs_invalidatepage,
 	.releasepage	= btrfs_releasepage,
 	.set_page_dirty	= btrfs_set_page_dirty,
+	.error_remove_page = generic_error_remove_page,
 };
 
 static const struct address_space_operations btrfs_symlink_aops = {
@@ -5309,3 +5866,7 @@ static const struct inode_operations btrfs_symlink_inode_operations = {
 	.listxattr	= btrfs_listxattr,
 	.removexattr	= btrfs_removexattr,
 };
+
+const struct dentry_operations btrfs_dentry_operations = {
+	.d_delete	= btrfs_dentry_delete,
+};
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index bd88f25..cdbb054 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -230,8 +230,8 @@ static noinline int create_subvol(struct btrfs_root *root,
 	struct btrfs_root_item root_item;
 	struct btrfs_inode_item *inode_item;
 	struct extent_buffer *leaf;
-	struct btrfs_root *new_root = root;
-	struct inode *dir;
+	struct btrfs_root *new_root;
+	struct inode *dir = dentry->d_parent->d_inode;
 	int ret;
 	int err;
 	u64 objectid;
@@ -239,9 +239,15 @@ static noinline int create_subvol(struct btrfs_root *root,
 	u64 index = 0;
 	unsigned long nr = 1;
 
-	ret = btrfs_check_metadata_free_space(root);
+	/*
+	 * 1 - inode item
+	 * 2 - refs
+	 * 1 - root item
+	 * 2 - dir items
+	 */
+	ret = btrfs_reserve_metadata_space(root, 6);
 	if (ret)
-		goto fail_commit;
+		return ret;
 
 	trans = btrfs_start_transaction(root, 1);
 	BUG_ON(!trans);
@@ -304,11 +310,17 @@ static noinline int create_subvol(struct btrfs_root *root,
 	if (ret)
 		goto fail;
 
+	key.offset = (u64)-1;
+	new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
+	BUG_ON(IS_ERR(new_root));
+
+	btrfs_record_root_in_trans(trans, new_root);
+
+	ret = btrfs_create_subvol_root(trans, new_root, new_dirid,
+				       BTRFS_I(dir)->block_group);
 	/*
 	 * insert the directory item
 	 */
-	key.offset = (u64)-1;
-	dir = dentry->d_parent->d_inode;
 	ret = btrfs_set_inode_index(dir, &index);
 	BUG_ON(ret);
 
@@ -322,43 +334,20 @@ static noinline int create_subvol(struct btrfs_root *root,
 	ret = btrfs_update_inode(trans, root, dir);
 	BUG_ON(ret);
 
-	/* add the backref first */
 	ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
-				 objectid, BTRFS_ROOT_BACKREF_KEY,
-				 root->root_key.objectid,
+				 objectid, root->root_key.objectid,
 				 dir->i_ino, index, name, namelen);
 
 	BUG_ON(ret);
 
-	/* now add the forward ref */
-	ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
-				 root->root_key.objectid, BTRFS_ROOT_REF_KEY,
-				 objectid,
-				 dir->i_ino, index, name, namelen);
-
-	BUG_ON(ret);
-
-	ret = btrfs_commit_transaction(trans, root);
-	if (ret)
-		goto fail_commit;
-
-	new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
-	BUG_ON(!new_root);
-
-	trans = btrfs_start_transaction(new_root, 1);
-	BUG_ON(!trans);
-
-	ret = btrfs_create_subvol_root(trans, new_root, dentry, new_dirid,
-				       BTRFS_I(dir)->block_group);
-	if (ret)
-		goto fail;
-
+	d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
 fail:
 	nr = trans->blocks_used;
-	err = btrfs_commit_transaction(trans, new_root);
+	err = btrfs_commit_transaction(trans, root);
 	if (err && !ret)
 		ret = err;
-fail_commit:
+
+	btrfs_unreserve_metadata_space(root, 6);
 	btrfs_btree_balance_dirty(root, nr);
 	return ret;
 }
@@ -375,19 +364,27 @@ static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
 	if (!root->ref_cows)
 		return -EINVAL;
 
-	ret = btrfs_check_metadata_free_space(root);
+	/*
+	 * 1 - inode item
+	 * 2 - refs
+	 * 1 - root item
+	 * 2 - dir items
+	 */
+	ret = btrfs_reserve_metadata_space(root, 6);
 	if (ret)
 		goto fail_unlock;
 
 	pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
 	if (!pending_snapshot) {
 		ret = -ENOMEM;
+		btrfs_unreserve_metadata_space(root, 6);
 		goto fail_unlock;
 	}
 	pending_snapshot->name = kmalloc(namelen + 1, GFP_NOFS);
 	if (!pending_snapshot->name) {
 		ret = -ENOMEM;
 		kfree(pending_snapshot);
+		btrfs_unreserve_metadata_space(root, 6);
 		goto fail_unlock;
 	}
 	memcpy(pending_snapshot->name, name, namelen);
@@ -420,14 +417,15 @@ static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
  * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
  * inside this filesystem so it's quite a bit simpler.
  */
-static noinline int btrfs_mksubvol(struct path *parent, char *name,
-				   int mode, int namelen,
+static noinline int btrfs_mksubvol(struct path *parent,
+				   char *name, int namelen,
 				   struct btrfs_root *snap_src)
 {
+	struct inode *dir  = parent->dentry->d_inode;
 	struct dentry *dentry;
 	int error;
 
-	mutex_lock_nested(&parent->dentry->d_inode->i_mutex, I_MUTEX_PARENT);
+	mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
 
 	dentry = lookup_one_len(name, parent->dentry, namelen);
 	error = PTR_ERR(dentry);
@@ -438,99 +436,39 @@ static noinline int btrfs_mksubvol(struct path *parent, char *name,
 	if (dentry->d_inode)
 		goto out_dput;
 
-	if (!IS_POSIXACL(parent->dentry->d_inode))
-		mode &= ~current_umask();
-
 	error = mnt_want_write(parent->mnt);
 	if (error)
 		goto out_dput;
 
-	error = btrfs_may_create(parent->dentry->d_inode, dentry);
+	error = btrfs_may_create(dir, dentry);
 	if (error)
 		goto out_drop_write;
 
-	/*
-	 * Actually perform the low-level subvolume creation after all
-	 * this VFS fuzz.
-	 *
-	 * Eventually we want to pass in an inode under which we create this
-	 * subvolume, but for now all are under the filesystem root.
-	 *
-	 * Also we should pass on the mode eventually to allow creating new
-	 * subvolume with specific mode bits.
-	 */
+	down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
+
+	if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
+		goto out_up_read;
+
 	if (snap_src) {
-		struct dentry *dir = dentry->d_parent;
-		struct dentry *test = dir->d_parent;
-		struct btrfs_path *path = btrfs_alloc_path();
-		int ret;
-		u64 test_oid;
-		u64 parent_oid = BTRFS_I(dir->d_inode)->root->root_key.objectid;
-
-		test_oid = snap_src->root_key.objectid;
-
-		ret = btrfs_find_root_ref(snap_src->fs_info->tree_root,
-					  path, parent_oid, test_oid);
-		if (ret == 0)
-			goto create;
-		btrfs_release_path(snap_src->fs_info->tree_root, path);
-
-		/* we need to make sure we aren't creating a directory loop
-		 * by taking a snapshot of something that has our current
-		 * subvol in its directory tree.  So, this loops through
-		 * the dentries and checks the forward refs for each subvolume
-		 * to see if is references the subvolume where we are
-		 * placing this new snapshot.
-		 */
-		while (1) {
-			if (!test ||
-			    dir == snap_src->fs_info->sb->s_root ||
-			    test == snap_src->fs_info->sb->s_root ||
-			    test->d_inode->i_sb != snap_src->fs_info->sb) {
-				break;
-			}
-			if (S_ISLNK(test->d_inode->i_mode)) {
-				printk(KERN_INFO "Btrfs symlink in snapshot "
-				       "path, failed\n");
-				error = -EMLINK;
-				btrfs_free_path(path);
-				goto out_drop_write;
-			}
-			test_oid =
-				BTRFS_I(test->d_inode)->root->root_key.objectid;
-			ret = btrfs_find_root_ref(snap_src->fs_info->tree_root,
-				  path, test_oid, parent_oid);
-			if (ret == 0) {
-				printk(KERN_INFO "Btrfs snapshot creation "
-				       "failed, looping\n");
-				error = -EMLINK;
-				btrfs_free_path(path);
-				goto out_drop_write;
-			}
-			btrfs_release_path(snap_src->fs_info->tree_root, path);
-			test = test->d_parent;
-		}
-create:
-		btrfs_free_path(path);
-		error = create_snapshot(snap_src, dentry, name, namelen);
+		error = create_snapshot(snap_src, dentry,
+					name, namelen);
 	} else {
-		error = create_subvol(BTRFS_I(parent->dentry->d_inode)->root,
-				      dentry, name, namelen);
+		error = create_subvol(BTRFS_I(dir)->root, dentry,
+				      name, namelen);
 	}
-	if (error)
-		goto out_drop_write;
-
-	fsnotify_mkdir(parent->dentry->d_inode, dentry);
+	if (!error)
+		fsnotify_mkdir(dir, dentry);
+out_up_read:
+	up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
 out_drop_write:
 	mnt_drop_write(parent->mnt);
 out_dput:
 	dput(dentry);
 out_unlock:
-	mutex_unlock(&parent->dentry->d_inode->i_mutex);
+	mutex_unlock(&dir->i_mutex);
 	return error;
 }
 
-
 static int btrfs_defrag_file(struct file *file)
 {
 	struct inode *inode = fdentry(file)->d_inode;
@@ -596,9 +534,8 @@ again:
 		clear_page_dirty_for_io(page);
 
 		btrfs_set_extent_delalloc(inode, page_start, page_end);
-
-		unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
 		set_page_dirty(page);
+		unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
 		unlock_page(page);
 		page_cache_release(page);
 		balance_dirty_pages_ratelimited_nr(inode->i_mapping, 1);
@@ -609,7 +546,8 @@ out_unlock:
 	return 0;
 }
 
-static int btrfs_ioctl_resize(struct btrfs_root *root, void __user *arg)
+static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
+					void __user *arg)
 {
 	u64 new_size;
 	u64 old_size;
@@ -718,10 +656,7 @@ static noinline int btrfs_ioctl_snap_create(struct file *file,
 {
 	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
 	struct btrfs_ioctl_vol_args *vol_args;
-	struct btrfs_dir_item *di;
-	struct btrfs_path *path;
 	struct file *src_file;
-	u64 root_dirid;
 	int namelen;
 	int ret = 0;
 
@@ -739,32 +674,9 @@ static noinline int btrfs_ioctl_snap_create(struct file *file,
 		goto out;
 	}
 
-	path = btrfs_alloc_path();
-	if (!path) {
-		ret = -ENOMEM;
-		goto out;
-	}
-
-	root_dirid = root->fs_info->sb->s_root->d_inode->i_ino,
-	di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root,
-			    path, root_dirid,
-			    vol_args->name, namelen, 0);
-	btrfs_free_path(path);
-
-	if (di && !IS_ERR(di)) {
-		ret = -EEXIST;
-		goto out;
-	}
-
-	if (IS_ERR(di)) {
-		ret = PTR_ERR(di);
-		goto out;
-	}
-
 	if (subvol) {
-		ret = btrfs_mksubvol(&file->f_path, vol_args->name,
-				     file->f_path.dentry->d_inode->i_mode,
-				     namelen, NULL);
+		ret = btrfs_mksubvol(&file->f_path, vol_args->name, namelen,
+				     NULL);
 	} else {
 		struct inode *src_inode;
 		src_file = fget(vol_args->fd);
@@ -781,17 +693,157 @@ static noinline int btrfs_ioctl_snap_create(struct file *file,
 			fput(src_file);
 			goto out;
 		}
-		ret = btrfs_mksubvol(&file->f_path, vol_args->name,
-			     file->f_path.dentry->d_inode->i_mode,
-			     namelen, BTRFS_I(src_inode)->root);
+		ret = btrfs_mksubvol(&file->f_path, vol_args->name, namelen,
+				     BTRFS_I(src_inode)->root);
 		fput(src_file);
 	}
-
 out:
 	kfree(vol_args);
 	return ret;
 }
 
+/*
+ * helper to check if the subvolume references other subvolumes
+ */
+static noinline int may_destroy_subvol(struct btrfs_root *root)
+{
+	struct btrfs_path *path;
+	struct btrfs_key key;
+	int ret;
+
+	path = btrfs_alloc_path();
+	if (!path)
+		return -ENOMEM;
+
+	key.objectid = root->root_key.objectid;
+	key.type = BTRFS_ROOT_REF_KEY;
+	key.offset = (u64)-1;
+
+	ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
+				&key, path, 0, 0);
+	if (ret < 0)
+		goto out;
+	BUG_ON(ret == 0);
+
+	ret = 0;
+	if (path->slots[0] > 0) {
+		path->slots[0]--;
+		btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
+		if (key.objectid == root->root_key.objectid &&
+		    key.type == BTRFS_ROOT_REF_KEY)
+			ret = -ENOTEMPTY;
+	}
+out:
+	btrfs_free_path(path);
+	return ret;
+}
+
+static noinline int btrfs_ioctl_snap_destroy(struct file *file,
+					     void __user *arg)
+{
+	struct dentry *parent = fdentry(file);
+	struct dentry *dentry;
+	struct inode *dir = parent->d_inode;
+	struct inode *inode;
+	struct btrfs_root *root = BTRFS_I(dir)->root;
+	struct btrfs_root *dest = NULL;
+	struct btrfs_ioctl_vol_args *vol_args;
+	struct btrfs_trans_handle *trans;
+	int namelen;
+	int ret;
+	int err = 0;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	vol_args = memdup_user(arg, sizeof(*vol_args));
+	if (IS_ERR(vol_args))
+		return PTR_ERR(vol_args);
+
+	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
+	namelen = strlen(vol_args->name);
+	if (strchr(vol_args->name, '/') ||
+	    strncmp(vol_args->name, "..", namelen) == 0) {
+		err = -EINVAL;
+		goto out;
+	}
+
+	err = mnt_want_write(file->f_path.mnt);
+	if (err)
+		goto out;
+
+	mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
+	dentry = lookup_one_len(vol_args->name, parent, namelen);
+	if (IS_ERR(dentry)) {
+		err = PTR_ERR(dentry);
+		goto out_unlock_dir;
+	}
+
+	if (!dentry->d_inode) {
+		err = -ENOENT;
+		goto out_dput;
+	}
+
+	inode = dentry->d_inode;
+	if (inode->i_ino != BTRFS_FIRST_FREE_OBJECTID) {
+		err = -EINVAL;
+		goto out_dput;
+	}
+
+	dest = BTRFS_I(inode)->root;
+
+	mutex_lock(&inode->i_mutex);
+	err = d_invalidate(dentry);
+	if (err)
+		goto out_unlock;
+
+	down_write(&root->fs_info->subvol_sem);
+
+	err = may_destroy_subvol(dest);
+	if (err)
+		goto out_up_write;
+
+	trans = btrfs_start_transaction(root, 1);
+	ret = btrfs_unlink_subvol(trans, root, dir,
+				dest->root_key.objectid,
+				dentry->d_name.name,
+				dentry->d_name.len);
+	BUG_ON(ret);
+
+	btrfs_record_root_in_trans(trans, dest);
+
+	memset(&dest->root_item.drop_progress, 0,
+		sizeof(dest->root_item.drop_progress));
+	dest->root_item.drop_level = 0;
+	btrfs_set_root_refs(&dest->root_item, 0);
+
+	ret = btrfs_insert_orphan_item(trans,
+				root->fs_info->tree_root,
+				dest->root_key.objectid);
+	BUG_ON(ret);
+
+	ret = btrfs_commit_transaction(trans, root);
+	BUG_ON(ret);
+	inode->i_flags |= S_DEAD;
+out_up_write:
+	up_write(&root->fs_info->subvol_sem);
+out_unlock:
+	mutex_unlock(&inode->i_mutex);
+	if (!err) {
+		shrink_dcache_sb(root->fs_info->sb);
+		btrfs_invalidate_inodes(dest);
+		d_delete(dentry);
+	}
+out_dput:
+	dput(dentry);
+out_unlock_dir:
+	mutex_unlock(&dir->i_mutex);
+	mnt_drop_write(file->f_path.mnt);
+out:
+	kfree(vol_args);
+	return err;
+}
+
 static int btrfs_ioctl_defrag(struct file *file)
 {
 	struct inode *inode = fdentry(file)->d_inode;
@@ -865,8 +917,8 @@ static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg)
 	return ret;
 }
 
-static long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
-		u64 off, u64 olen, u64 destoff)
+static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
+				       u64 off, u64 olen, u64 destoff)
 {
 	struct inode *inode = fdentry(file)->d_inode;
 	struct btrfs_root *root = BTRFS_I(inode)->root;
@@ -976,7 +1028,7 @@ static long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
 
 	/* punch hole in destination first */
 	btrfs_drop_extents(trans, root, inode, off, off + len,
-			   off + len, 0, &hint_byte);
+			   off + len, 0, &hint_byte, 1);
 
 	/* clone data */
 	key.objectid = src->i_ino;
@@ -1071,9 +1123,10 @@ static long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
 					datao += off - key.offset;
 					datal -= off - key.offset;
 				}
-				if (key.offset + datao + datal + key.offset >
-				    off + len)
-					datal = off + len - key.offset - datao;
+
+				if (key.offset + datal > off + len)
+					datal = off + len - key.offset;
+
 				/* disko == 0 means it's a hole */
 				if (!disko)
 					datao = 0;
@@ -1182,15 +1235,15 @@ static long btrfs_ioctl_trans_start(struct file *file)
 	struct inode *inode = fdentry(file)->d_inode;
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct btrfs_trans_handle *trans;
-	int ret = 0;
+	int ret;
 
+	ret = -EPERM;
 	if (!capable(CAP_SYS_ADMIN))
-		return -EPERM;
+		goto out;
 
-	if (file->private_data) {
-		ret = -EINPROGRESS;
+	ret = -EINPROGRESS;
+	if (file->private_data)
 		goto out;
-	}
 
 	ret = mnt_want_write(file->f_path.mnt);
 	if (ret)
@@ -1200,12 +1253,19 @@ static long btrfs_ioctl_trans_start(struct file *file)
 	root->fs_info->open_ioctl_trans++;
 	mutex_unlock(&root->fs_info->trans_mutex);
 
+	ret = -ENOMEM;
 	trans = btrfs_start_ioctl_transaction(root, 0);
-	if (trans)
-		file->private_data = trans;
-	else
-		ret = -ENOMEM;
-	/*printk(KERN_INFO "btrfs_ioctl_trans_start on %p\n", file);*/
+	if (!trans)
+		goto out_drop;
+
+	file->private_data = trans;
+	return 0;
+
+out_drop:
+	mutex_lock(&root->fs_info->trans_mutex);
+	root->fs_info->open_ioctl_trans--;
+	mutex_unlock(&root->fs_info->trans_mutex);
+	mnt_drop_write(file->f_path.mnt);
 out:
 	return ret;
 }
@@ -1221,24 +1281,20 @@ long btrfs_ioctl_trans_end(struct file *file)
 	struct inode *inode = fdentry(file)->d_inode;
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct btrfs_trans_handle *trans;
-	int ret = 0;
 
 	trans = file->private_data;
-	if (!trans) {
-		ret = -EINVAL;
-		goto out;
-	}
-	btrfs_end_transaction(trans, root);
+	if (!trans)
+		return -EINVAL;
 	file->private_data = NULL;
 
+	btrfs_end_transaction(trans, root);
+
 	mutex_lock(&root->fs_info->trans_mutex);
 	root->fs_info->open_ioctl_trans--;
 	mutex_unlock(&root->fs_info->trans_mutex);
 
 	mnt_drop_write(file->f_path.mnt);
-
-out:
-	return ret;
+	return 0;
 }
 
 long btrfs_ioctl(struct file *file, unsigned int
@@ -1258,6 +1314,8 @@ long btrfs_ioctl(struct file *file, unsigned int
 		return btrfs_ioctl_snap_create(file, argp, 0);
 	case BTRFS_IOC_SUBVOL_CREATE:
 		return btrfs_ioctl_snap_create(file, argp, 1);
+	case BTRFS_IOC_SNAP_DESTROY:
+		return btrfs_ioctl_snap_destroy(file, argp);
 	case BTRFS_IOC_DEFRAG:
 		return btrfs_ioctl_defrag(file);
 	case BTRFS_IOC_RESIZE:
diff --git a/fs/btrfs/ioctl.h b/fs/btrfs/ioctl.h
index b320b10..bc49914 100644
--- a/fs/btrfs/ioctl.h
+++ b/fs/btrfs/ioctl.h
@@ -65,5 +65,6 @@ struct btrfs_ioctl_clone_range_args {
 
 #define BTRFS_IOC_SUBVOL_CREATE _IOW(BTRFS_IOCTL_MAGIC, 14, \
 				   struct btrfs_ioctl_vol_args)
-
+#define BTRFS_IOC_SNAP_DESTROY _IOW(BTRFS_IOCTL_MAGIC, 15, \
+				struct btrfs_ioctl_vol_args)
 #endif
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index 7b2f401..5799bc4 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -159,8 +159,6 @@ static inline struct rb_node *tree_search(struct btrfs_ordered_inode_tree *tree,
  *
  * len is the length of the extent
  *
- * This also sets the EXTENT_ORDERED bit on the range in the inode.
- *
  * The tree is given a single reference on the ordered extent that was
  * inserted.
  */
@@ -181,6 +179,7 @@ int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
 	entry->start = start;
 	entry->len = len;
 	entry->disk_len = disk_len;
+	entry->bytes_left = len;
 	entry->inode = inode;
 	if (type != BTRFS_ORDERED_IO_DONE && type != BTRFS_ORDERED_COMPLETE)
 		set_bit(type, &entry->flags);
@@ -195,9 +194,6 @@ int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
 			   &entry->rb_node);
 	BUG_ON(node);
 
-	set_extent_ordered(&BTRFS_I(inode)->io_tree, file_offset,
-			   entry_end(entry) - 1, GFP_NOFS);
-
 	spin_lock(&BTRFS_I(inode)->root->fs_info->ordered_extent_lock);
 	list_add_tail(&entry->root_extent_list,
 		      &BTRFS_I(inode)->root->fs_info->ordered_extents);
@@ -241,13 +237,10 @@ int btrfs_dec_test_ordered_pending(struct inode *inode,
 	struct btrfs_ordered_inode_tree *tree;
 	struct rb_node *node;
 	struct btrfs_ordered_extent *entry;
-	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 	int ret;
 
 	tree = &BTRFS_I(inode)->ordered_tree;
 	mutex_lock(&tree->mutex);
-	clear_extent_ordered(io_tree, file_offset, file_offset + io_size - 1,
-			     GFP_NOFS);
 	node = tree_search(tree, file_offset);
 	if (!node) {
 		ret = 1;
@@ -260,11 +253,16 @@ int btrfs_dec_test_ordered_pending(struct inode *inode,
 		goto out;
 	}
 
-	ret = test_range_bit(io_tree, entry->file_offset,
-			     entry->file_offset + entry->len - 1,
-			     EXTENT_ORDERED, 0);
-	if (ret == 0)
+	if (io_size > entry->bytes_left) {
+		printk(KERN_CRIT "bad ordered accounting left %llu size %llu\n",
+		       (unsigned long long)entry->bytes_left,
+		       (unsigned long long)io_size);
+	}
+	entry->bytes_left -= io_size;
+	if (entry->bytes_left == 0)
 		ret = test_and_set_bit(BTRFS_ORDERED_IO_DONE, &entry->flags);
+	else
+		ret = 1;
 out:
 	mutex_unlock(&tree->mutex);
 	return ret == 0;
@@ -308,6 +306,12 @@ int btrfs_remove_ordered_extent(struct inode *inode,
 	tree->last = NULL;
 	set_bit(BTRFS_ORDERED_COMPLETE, &entry->flags);
 
+	spin_lock(&BTRFS_I(inode)->accounting_lock);
+	BTRFS_I(inode)->outstanding_extents--;
+	spin_unlock(&BTRFS_I(inode)->accounting_lock);
+	btrfs_unreserve_metadata_for_delalloc(BTRFS_I(inode)->root,
+					      inode, 1);
+
 	spin_lock(&BTRFS_I(inode)->root->fs_info->ordered_extent_lock);
 	list_del_init(&entry->root_extent_list);
 
@@ -460,7 +464,7 @@ void btrfs_start_ordered_extent(struct inode *inode,
 	 * start IO on any dirty ones so the wait doesn't stall waiting
 	 * for pdflush to find them
 	 */
-	btrfs_fdatawrite_range(inode->i_mapping, start, end, WB_SYNC_ALL);
+	filemap_fdatawrite_range(inode->i_mapping, start, end);
 	if (wait) {
 		wait_event(entry->wait, test_bit(BTRFS_ORDERED_COMPLETE,
 						 &entry->flags));
@@ -476,6 +480,7 @@ int btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len)
 	u64 orig_end;
 	u64 wait_end;
 	struct btrfs_ordered_extent *ordered;
+	int found;
 
 	if (start + len < start) {
 		orig_end = INT_LIMIT(loff_t);
@@ -489,19 +494,18 @@ again:
 	/* start IO across the range first to instantiate any delalloc
 	 * extents
 	 */
-	btrfs_fdatawrite_range(inode->i_mapping, start, orig_end, WB_SYNC_ALL);
+	filemap_fdatawrite_range(inode->i_mapping, start, orig_end);
 
 	/* The compression code will leave pages locked but return from
 	 * writepage without setting the page writeback.  Starting again
 	 * with WB_SYNC_ALL will end up waiting for the IO to actually start.
 	 */
-	btrfs_fdatawrite_range(inode->i_mapping, start, orig_end, WB_SYNC_ALL);
+	filemap_fdatawrite_range(inode->i_mapping, start, orig_end);
 
-	btrfs_wait_on_page_writeback_range(inode->i_mapping,
-					   start >> PAGE_CACHE_SHIFT,
-					   orig_end >> PAGE_CACHE_SHIFT);
+	filemap_fdatawait_range(inode->i_mapping, start, orig_end);
 
 	end = orig_end;
+	found = 0;
 	while (1) {
 		ordered = btrfs_lookup_first_ordered_extent(inode, end);
 		if (!ordered)
@@ -514,6 +518,7 @@ again:
 			btrfs_put_ordered_extent(ordered);
 			break;
 		}
+		found++;
 		btrfs_start_ordered_extent(inode, ordered, 1);
 		end = ordered->file_offset;
 		btrfs_put_ordered_extent(ordered);
@@ -521,8 +526,8 @@ again:
 			break;
 		end--;
 	}
-	if (test_range_bit(&BTRFS_I(inode)->io_tree, start, orig_end,
-			   EXTENT_ORDERED | EXTENT_DELALLOC, 0)) {
+	if (found || test_range_bit(&BTRFS_I(inode)->io_tree, start, orig_end,
+			   EXTENT_DELALLOC, 0, NULL)) {
 		schedule_timeout(1);
 		goto again;
 	}
@@ -613,7 +618,7 @@ int btrfs_ordered_update_i_size(struct inode *inode,
 	 */
 	if (test_range_bit(io_tree, disk_i_size,
 			   ordered->file_offset + ordered->len - 1,
-			   EXTENT_DELALLOC, 0)) {
+			   EXTENT_DELALLOC, 0, NULL)) {
 		goto out;
 	}
 	/*
@@ -664,7 +669,7 @@ int btrfs_ordered_update_i_size(struct inode *inode,
 	 */
 	if (i_size_test > entry_end(ordered) &&
 	    !test_range_bit(io_tree, entry_end(ordered), i_size_test - 1,
-			   EXTENT_DELALLOC, 0)) {
+			   EXTENT_DELALLOC, 0, NULL)) {
 		new_i_size = min_t(u64, i_size_test, i_size_read(inode));
 	}
 	BTRFS_I(inode)->disk_i_size = new_i_size;
@@ -715,89 +720,6 @@ out:
 }
 
 
-/**
- * taken from mm/filemap.c because it isn't exported
- *
- * __filemap_fdatawrite_range - start writeback on mapping dirty pages in range
- * @mapping:	address space structure to write
- * @start:	offset in bytes where the range starts
- * @end:	offset in bytes where the range ends (inclusive)
- * @sync_mode:	enable synchronous operation
- *
- * Start writeback against all of a mapping's dirty pages that lie
- * within the byte offsets <start, end> inclusive.
- *
- * If sync_mode is WB_SYNC_ALL then this is a "data integrity" operation, as
- * opposed to a regular memory cleansing writeback.  The difference between
- * these two operations is that if a dirty page/buffer is encountered, it must
- * be waited upon, and not just skipped over.
- */
-int btrfs_fdatawrite_range(struct address_space *mapping, loff_t start,
-			   loff_t end, int sync_mode)
-{
-	struct writeback_control wbc = {
-		.sync_mode = sync_mode,
-		.nr_to_write = mapping->nrpages * 2,
-		.range_start = start,
-		.range_end = end,
-	};
-	return btrfs_writepages(mapping, &wbc);
-}
-
-/**
- * taken from mm/filemap.c because it isn't exported
- *
- * wait_on_page_writeback_range - wait for writeback to complete
- * @mapping:	target address_space
- * @start:	beginning page index
- * @end:	ending page index
- *
- * Wait for writeback to complete against pages indexed by start->end
- * inclusive
- */
-int btrfs_wait_on_page_writeback_range(struct address_space *mapping,
-				       pgoff_t start, pgoff_t end)
-{
-	struct pagevec pvec;
-	int nr_pages;
-	int ret = 0;
-	pgoff_t index;
-
-	if (end < start)
-		return 0;
-
-	pagevec_init(&pvec, 0);
-	index = start;
-	while ((index <= end) &&
-			(nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
-			PAGECACHE_TAG_WRITEBACK,
-			min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1)) != 0) {
-		unsigned i;
-
-		for (i = 0; i < nr_pages; i++) {
-			struct page *page = pvec.pages[i];
-
-			/* until radix tree lookup accepts end_index */
-			if (page->index > end)
-				continue;
-
-			wait_on_page_writeback(page);
-			if (PageError(page))
-				ret = -EIO;
-		}
-		pagevec_release(&pvec);
-		cond_resched();
-	}
-
-	/* Check for outstanding write errors */
-	if (test_and_clear_bit(AS_ENOSPC, &mapping->flags))
-		ret = -ENOSPC;
-	if (test_and_clear_bit(AS_EIO, &mapping->flags))
-		ret = -EIO;
-
-	return ret;
-}
-
 /*
  * add a given inode to the list of inodes that must be fully on
  * disk before a transaction commit finishes.
diff --git a/fs/btrfs/ordered-data.h b/fs/btrfs/ordered-data.h
index 3d31c88..f82e874 100644
--- a/fs/btrfs/ordered-data.h
+++ b/fs/btrfs/ordered-data.h
@@ -85,6 +85,9 @@ struct btrfs_ordered_extent {
 	/* extent length on disk */
 	u64 disk_len;
 
+	/* number of bytes that still need writing */
+	u64 bytes_left;
+
 	/* flags (described above) */
 	unsigned long flags;
 
@@ -150,10 +153,6 @@ btrfs_lookup_first_ordered_extent(struct inode * inode, u64 file_offset);
 int btrfs_ordered_update_i_size(struct inode *inode,
 				struct btrfs_ordered_extent *ordered);
 int btrfs_find_ordered_sum(struct inode *inode, u64 offset, u64 disk_bytenr, u32 *sum);
-int btrfs_wait_on_page_writeback_range(struct address_space *mapping,
-				       pgoff_t start, pgoff_t end);
-int btrfs_fdatawrite_range(struct address_space *mapping, loff_t start,
-			   loff_t end, int sync_mode);
 int btrfs_wait_ordered_extents(struct btrfs_root *root, int nocow_only);
 int btrfs_run_ordered_operations(struct btrfs_root *root, int wait);
 int btrfs_add_ordered_operation(struct btrfs_trans_handle *trans,
diff --git a/fs/btrfs/orphan.c b/fs/btrfs/orphan.c
index 3c0d52a..79cba5f 100644
--- a/fs/btrfs/orphan.c
+++ b/fs/btrfs/orphan.c
@@ -65,3 +65,23 @@ out:
 	btrfs_free_path(path);
 	return ret;
 }
+
+int btrfs_find_orphan_item(struct btrfs_root *root, u64 offset)
+{
+	struct btrfs_path *path;
+	struct btrfs_key key;
+	int ret;
+
+	key.objectid = BTRFS_ORPHAN_OBJECTID;
+	key.type = BTRFS_ORPHAN_ITEM_KEY;
+	key.offset = offset;
+
+	path = btrfs_alloc_path();
+	if (!path)
+		return -ENOMEM;
+
+	ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
+
+	btrfs_free_path(path);
+	return ret;
+}
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index c04f7f2..cfcc93c 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -121,6 +121,15 @@ struct inodevec {
 	int nr;
 };
 
+#define MAX_EXTENTS 128
+
+struct file_extent_cluster {
+	u64 start;
+	u64 end;
+	u64 boundary[MAX_EXTENTS];
+	unsigned int nr;
+};
+
 struct reloc_control {
 	/* block group to relocate */
 	struct btrfs_block_group_cache *block_group;
@@ -2180,7 +2189,7 @@ static int tree_block_processed(u64 bytenr, u32 blocksize,
 				struct reloc_control *rc)
 {
 	if (test_range_bit(&rc->processed_blocks, bytenr,
-			   bytenr + blocksize - 1, EXTENT_DIRTY, 1))
+			   bytenr + blocksize - 1, EXTENT_DIRTY, 1, NULL))
 		return 1;
 	return 0;
 }
@@ -2529,56 +2538,94 @@ out:
 }
 
 static noinline_for_stack
-int relocate_inode_pages(struct inode *inode, u64 start, u64 len)
+int setup_extent_mapping(struct inode *inode, u64 start, u64 end,
+			 u64 block_start)
+{
+	struct btrfs_root *root = BTRFS_I(inode)->root;
+	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
+	struct extent_map *em;
+	int ret = 0;
+
+	em = alloc_extent_map(GFP_NOFS);
+	if (!em)
+		return -ENOMEM;
+
+	em->start = start;
+	em->len = end + 1 - start;
+	em->block_len = em->len;
+	em->block_start = block_start;
+	em->bdev = root->fs_info->fs_devices->latest_bdev;
+	set_bit(EXTENT_FLAG_PINNED, &em->flags);
+
+	lock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS);
+	while (1) {
+		write_lock(&em_tree->lock);
+		ret = add_extent_mapping(em_tree, em);
+		write_unlock(&em_tree->lock);
+		if (ret != -EEXIST) {
+			free_extent_map(em);
+			break;
+		}
+		btrfs_drop_extent_cache(inode, start, end, 0);
+	}
+	unlock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS);
+	return ret;
+}
+
+static int relocate_file_extent_cluster(struct inode *inode,
+					struct file_extent_cluster *cluster)
 {
 	u64 page_start;
 	u64 page_end;
-	unsigned long i;
-	unsigned long first_index;
+	u64 offset = BTRFS_I(inode)->index_cnt;
+	unsigned long index;
 	unsigned long last_index;
-	unsigned int total_read = 0;
-	unsigned int total_dirty = 0;
+	unsigned int dirty_page = 0;
 	struct page *page;
 	struct file_ra_state *ra;
-	struct btrfs_ordered_extent *ordered;
-	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
+	int nr = 0;
 	int ret = 0;
 
+	if (!cluster->nr)
+		return 0;
+
 	ra = kzalloc(sizeof(*ra), GFP_NOFS);
 	if (!ra)
 		return -ENOMEM;
 
+	index = (cluster->start - offset) >> PAGE_CACHE_SHIFT;
+	last_index = (cluster->end - offset) >> PAGE_CACHE_SHIFT;
+
 	mutex_lock(&inode->i_mutex);
-	first_index = start >> PAGE_CACHE_SHIFT;
-	last_index = (start + len - 1) >> PAGE_CACHE_SHIFT;
 
-	/* make sure the dirty trick played by the caller work */
-	while (1) {
-		ret = invalidate_inode_pages2_range(inode->i_mapping,
-						    first_index, last_index);
-		if (ret != -EBUSY)
-			break;
-		schedule_timeout(HZ/10);
-	}
+	i_size_write(inode, cluster->end + 1 - offset);
+	ret = setup_extent_mapping(inode, cluster->start - offset,
+				   cluster->end - offset, cluster->start);
 	if (ret)
 		goto out_unlock;
 
 	file_ra_state_init(ra, inode->i_mapping);
 
-	for (i = first_index ; i <= last_index; i++) {
-		if (total_read % ra->ra_pages == 0) {
-			btrfs_force_ra(inode->i_mapping, ra, NULL, i,
-				min(last_index, ra->ra_pages + i - 1));
-		}
-		total_read++;
-again:
-		if (((u64)i << PAGE_CACHE_SHIFT) > i_size_read(inode))
-			BUG_ON(1);
-		page = grab_cache_page(inode->i_mapping, i);
+	WARN_ON(cluster->start != cluster->boundary[0]);
+	while (index <= last_index) {
+		page = find_lock_page(inode->i_mapping, index);
 		if (!page) {
-			ret = -ENOMEM;
-			goto out_unlock;
+			page_cache_sync_readahead(inode->i_mapping,
+						  ra, NULL, index,
+						  last_index + 1 - index);
+			page = grab_cache_page(inode->i_mapping, index);
+			if (!page) {
+				ret = -ENOMEM;
+				goto out_unlock;
+			}
+		}
+
+		if (PageReadahead(page)) {
+			page_cache_async_readahead(inode->i_mapping,
+						   ra, NULL, page, index,
+						   last_index + 1 - index);
 		}
+
 		if (!PageUptodate(page)) {
 			btrfs_readpage(NULL, page);
 			lock_page(page);
@@ -2589,75 +2636,79 @@ again:
 				goto out_unlock;
 			}
 		}
-		wait_on_page_writeback(page);
 
 		page_start = (u64)page->index << PAGE_CACHE_SHIFT;
 		page_end = page_start + PAGE_CACHE_SIZE - 1;
-		lock_extent(io_tree, page_start, page_end, GFP_NOFS);
-
-		ordered = btrfs_lookup_ordered_extent(inode, page_start);
-		if (ordered) {
-			unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
-			unlock_page(page);
-			page_cache_release(page);
-			btrfs_start_ordered_extent(inode, ordered, 1);
-			btrfs_put_ordered_extent(ordered);
-			goto again;
-		}
+
+		lock_extent(&BTRFS_I(inode)->io_tree,
+			    page_start, page_end, GFP_NOFS);
+
 		set_page_extent_mapped(page);
 
-		if (i == first_index)
-			set_extent_bits(io_tree, page_start, page_end,
+		if (nr < cluster->nr &&
+		    page_start + offset == cluster->boundary[nr]) {
+			set_extent_bits(&BTRFS_I(inode)->io_tree,
+					page_start, page_end,
 					EXTENT_BOUNDARY, GFP_NOFS);
+			nr++;
+		}
 		btrfs_set_extent_delalloc(inode, page_start, page_end);
 
 		set_page_dirty(page);
-		total_dirty++;
+		dirty_page++;
 
-		unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
+		unlock_extent(&BTRFS_I(inode)->io_tree,
+			      page_start, page_end, GFP_NOFS);
 		unlock_page(page);
 		page_cache_release(page);
+
+		index++;
+		if (nr < cluster->nr &&
+		    page_end + 1 + offset == cluster->boundary[nr]) {
+			balance_dirty_pages_ratelimited_nr(inode->i_mapping,
+							   dirty_page);
+			dirty_page = 0;
+		}
+	}
+	if (dirty_page) {
+		balance_dirty_pages_ratelimited_nr(inode->i_mapping,
+						   dirty_page);
 	}
+	WARN_ON(nr != cluster->nr);
 out_unlock:
 	mutex_unlock(&inode->i_mutex);
 	kfree(ra);
-	balance_dirty_pages_ratelimited_nr(inode->i_mapping, total_dirty);
 	return ret;
 }
 
 static noinline_for_stack
-int relocate_data_extent(struct inode *inode, struct btrfs_key *extent_key)
+int relocate_data_extent(struct inode *inode, struct btrfs_key *extent_key,
+			 struct file_extent_cluster *cluster)
 {
-	struct btrfs_root *root = BTRFS_I(inode)->root;
-	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
-	struct extent_map *em;
-	u64 start = extent_key->objectid - BTRFS_I(inode)->index_cnt;
-	u64 end = start + extent_key->offset - 1;
-
-	em = alloc_extent_map(GFP_NOFS);
-	em->start = start;
-	em->len = extent_key->offset;
-	em->block_len = extent_key->offset;
-	em->block_start = extent_key->objectid;
-	em->bdev = root->fs_info->fs_devices->latest_bdev;
-	set_bit(EXTENT_FLAG_PINNED, &em->flags);
+	int ret;
 
-	/* setup extent map to cheat btrfs_readpage */
-	lock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS);
-	while (1) {
-		int ret;
-		spin_lock(&em_tree->lock);
-		ret = add_extent_mapping(em_tree, em);
-		spin_unlock(&em_tree->lock);
-		if (ret != -EEXIST) {
-			free_extent_map(em);
-			break;
-		}
-		btrfs_drop_extent_cache(inode, start, end, 0);
+	if (cluster->nr > 0 && extent_key->objectid != cluster->end + 1) {
+		ret = relocate_file_extent_cluster(inode, cluster);
+		if (ret)
+			return ret;
+		cluster->nr = 0;
 	}
-	unlock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS);
 
-	return relocate_inode_pages(inode, start, extent_key->offset);
+	if (!cluster->nr)
+		cluster->start = extent_key->objectid;
+	else
+		BUG_ON(cluster->nr >= MAX_EXTENTS);
+	cluster->end = extent_key->objectid + extent_key->offset - 1;
+	cluster->boundary[cluster->nr] = extent_key->objectid;
+	cluster->nr++;
+
+	if (cluster->nr >= MAX_EXTENTS) {
+		ret = relocate_file_extent_cluster(inode, cluster);
+		if (ret)
+			return ret;
+		cluster->nr = 0;
+	}
+	return 0;
 }
 
 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
@@ -3203,10 +3254,12 @@ static int check_extent_flags(u64 flags)
 	return 0;
 }
 
+
 static noinline_for_stack int relocate_block_group(struct reloc_control *rc)
 {
 	struct rb_root blocks = RB_ROOT;
 	struct btrfs_key key;
+	struct file_extent_cluster *cluster;
 	struct btrfs_trans_handle *trans = NULL;
 	struct btrfs_path *path;
 	struct btrfs_extent_item *ei;
@@ -3216,10 +3269,17 @@ static noinline_for_stack int relocate_block_group(struct reloc_control *rc)
 	int ret;
 	int err = 0;
 
+	cluster = kzalloc(sizeof(*cluster), GFP_NOFS);
+	if (!cluster)
+		return -ENOMEM;
+
 	path = btrfs_alloc_path();
 	if (!path)
 		return -ENOMEM;
 
+	rc->extents_found = 0;
+	rc->extents_skipped = 0;
+
 	rc->search_start = rc->block_group->key.objectid;
 	clear_extent_bits(&rc->processed_blocks, 0, (u64)-1, EXTENT_DIRTY,
 			  GFP_NOFS);
@@ -3306,14 +3366,15 @@ static noinline_for_stack int relocate_block_group(struct reloc_control *rc)
 		}
 
 		nr = trans->blocks_used;
-		btrfs_end_transaction_throttle(trans, rc->extent_root);
+		btrfs_end_transaction(trans, rc->extent_root);
 		trans = NULL;
 		btrfs_btree_balance_dirty(rc->extent_root, nr);
 
 		if (rc->stage == MOVE_DATA_EXTENTS &&
 		    (flags & BTRFS_EXTENT_FLAG_DATA)) {
 			rc->found_file_extent = 1;
-			ret = relocate_data_extent(rc->data_inode, &key);
+			ret = relocate_data_extent(rc->data_inode,
+						   &key, cluster);
 			if (ret < 0) {
 				err = ret;
 				break;
@@ -3328,6 +3389,14 @@ static noinline_for_stack int relocate_block_group(struct reloc_control *rc)
 		btrfs_btree_balance_dirty(rc->extent_root, nr);
 	}
 
+	if (!err) {
+		ret = relocate_file_extent_cluster(rc->data_inode, cluster);
+		if (ret < 0)
+			err = ret;
+	}
+
+	kfree(cluster);
+
 	rc->create_reloc_root = 0;
 	smp_mb();
 
@@ -3348,8 +3417,7 @@ static noinline_for_stack int relocate_block_group(struct reloc_control *rc)
 }
 
 static int __insert_orphan_inode(struct btrfs_trans_handle *trans,
-				 struct btrfs_root *root,
-				 u64 objectid, u64 size)
+				 struct btrfs_root *root, u64 objectid)
 {
 	struct btrfs_path *path;
 	struct btrfs_inode_item *item;
@@ -3368,7 +3436,7 @@ static int __insert_orphan_inode(struct btrfs_trans_handle *trans,
 	item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_inode_item);
 	memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item));
 	btrfs_set_inode_generation(leaf, item, 1);
-	btrfs_set_inode_size(leaf, item, size);
+	btrfs_set_inode_size(leaf, item, 0);
 	btrfs_set_inode_mode(leaf, item, S_IFREG | 0600);
 	btrfs_set_inode_flags(leaf, item, BTRFS_INODE_NOCOMPRESS);
 	btrfs_mark_buffer_dirty(leaf);
@@ -3404,12 +3472,7 @@ static struct inode *create_reloc_inode(struct btrfs_fs_info *fs_info,
 	if (err)
 		goto out;
 
-	err = __insert_orphan_inode(trans, root, objectid, group->key.offset);
-	BUG_ON(err);
-
-	err = btrfs_insert_file_extent(trans, root, objectid, 0, 0, 0,
-				       group->key.offset, 0, group->key.offset,
-				       0, 0, 0);
+	err = __insert_orphan_inode(trans, root, objectid);
 	BUG_ON(err);
 
 	key.objectid = objectid;
@@ -3455,7 +3518,7 @@ int btrfs_relocate_block_group(struct btrfs_root *extent_root, u64 group_start)
 	BUG_ON(!rc->block_group);
 
 	btrfs_init_workers(&rc->workers, "relocate",
-			   fs_info->thread_pool_size);
+			   fs_info->thread_pool_size, NULL);
 
 	rc->extent_root = extent_root;
 	btrfs_prepare_block_group_relocation(extent_root, rc->block_group);
@@ -3475,14 +3538,15 @@ int btrfs_relocate_block_group(struct btrfs_root *extent_root, u64 group_start)
 	btrfs_wait_ordered_extents(fs_info->tree_root, 0);
 
 	while (1) {
-		mutex_lock(&fs_info->cleaner_mutex);
-		btrfs_clean_old_snapshots(fs_info->tree_root);
-		mutex_unlock(&fs_info->cleaner_mutex);
-
 		rc->extents_found = 0;
 		rc->extents_skipped = 0;
 
+		mutex_lock(&fs_info->cleaner_mutex);
+
+		btrfs_clean_old_snapshots(fs_info->tree_root);
 		ret = relocate_block_group(rc);
+
+		mutex_unlock(&fs_info->cleaner_mutex);
 		if (ret < 0) {
 			err = ret;
 			break;
@@ -3514,10 +3578,10 @@ int btrfs_relocate_block_group(struct btrfs_root *extent_root, u64 group_start)
 		}
 	}
 
-	filemap_fdatawrite_range(fs_info->btree_inode->i_mapping,
-				 rc->block_group->key.objectid,
-				 rc->block_group->key.objectid +
-				 rc->block_group->key.offset - 1);
+	filemap_write_and_wait_range(fs_info->btree_inode->i_mapping,
+				     rc->block_group->key.objectid,
+				     rc->block_group->key.objectid +
+				     rc->block_group->key.offset - 1);
 
 	WARN_ON(rc->block_group->pinned > 0);
 	WARN_ON(rc->block_group->reserved > 0);
@@ -3530,6 +3594,26 @@ out:
 	return err;
 }
 
+static noinline_for_stack int mark_garbage_root(struct btrfs_root *root)
+{
+	struct btrfs_trans_handle *trans;
+	int ret;
+
+	trans = btrfs_start_transaction(root->fs_info->tree_root, 1);
+
+	memset(&root->root_item.drop_progress, 0,
+		sizeof(root->root_item.drop_progress));
+	root->root_item.drop_level = 0;
+	btrfs_set_root_refs(&root->root_item, 0);
+	ret = btrfs_update_root(trans, root->fs_info->tree_root,
+				&root->root_key, &root->root_item);
+	BUG_ON(ret);
+
+	ret = btrfs_end_transaction(trans, root->fs_info->tree_root);
+	BUG_ON(ret);
+	return 0;
+}
+
 /*
  * recover relocation interrupted by system crash.
  *
@@ -3589,8 +3673,12 @@ int btrfs_recover_relocation(struct btrfs_root *root)
 			fs_root = read_fs_root(root->fs_info,
 					       reloc_root->root_key.offset);
 			if (IS_ERR(fs_root)) {
-				err = PTR_ERR(fs_root);
-				goto out;
+				ret = PTR_ERR(fs_root);
+				if (ret != -ENOENT) {
+					err = ret;
+					goto out;
+				}
+				mark_garbage_root(reloc_root);
 			}
 		}
 
@@ -3613,7 +3701,7 @@ int btrfs_recover_relocation(struct btrfs_root *root)
 	mapping_tree_init(&rc->reloc_root_tree);
 	INIT_LIST_HEAD(&rc->reloc_roots);
 	btrfs_init_workers(&rc->workers, "relocate",
-			   root->fs_info->thread_pool_size);
+			   root->fs_info->thread_pool_size, NULL);
 	rc->extent_root = root->fs_info->extent_root;
 
 	set_reloc_control(rc);
diff --git a/fs/btrfs/root-tree.c b/fs/btrfs/root-tree.c
index 0ddc6d6..9351428 100644
--- a/fs/btrfs/root-tree.c
+++ b/fs/btrfs/root-tree.c
@@ -94,17 +94,23 @@ int btrfs_find_last_root(struct btrfs_root *root, u64 objectid,
 		goto out;
 
 	BUG_ON(ret == 0);
+	if (path->slots[0] == 0) {
+		ret = 1;
+		goto out;
+	}
 	l = path->nodes[0];
-	BUG_ON(path->slots[0] == 0);
 	slot = path->slots[0] - 1;
 	btrfs_item_key_to_cpu(l, &found_key, slot);
-	if (found_key.objectid != objectid) {
+	if (found_key.objectid != objectid ||
+	    found_key.type != BTRFS_ROOT_ITEM_KEY) {
 		ret = 1;
 		goto out;
 	}
-	read_extent_buffer(l, item, btrfs_item_ptr_offset(l, slot),
-			   sizeof(*item));
-	memcpy(key, &found_key, sizeof(found_key));
+	if (item)
+		read_extent_buffer(l, item, btrfs_item_ptr_offset(l, slot),
+				   sizeof(*item));
+	if (key)
+		memcpy(key, &found_key, sizeof(found_key));
 	ret = 0;
 out:
 	btrfs_free_path(path);
@@ -249,6 +255,59 @@ err:
 	return ret;
 }
 
+int btrfs_find_orphan_roots(struct btrfs_root *tree_root)
+{
+	struct extent_buffer *leaf;
+	struct btrfs_path *path;
+	struct btrfs_key key;
+	int err = 0;
+	int ret;
+
+	path = btrfs_alloc_path();
+	if (!path)
+		return -ENOMEM;
+
+	key.objectid = BTRFS_ORPHAN_OBJECTID;
+	key.type = BTRFS_ORPHAN_ITEM_KEY;
+	key.offset = 0;
+
+	while (1) {
+		ret = btrfs_search_slot(NULL, tree_root, &key, path, 0, 0);
+		if (ret < 0) {
+			err = ret;
+			break;
+		}
+
+		leaf = path->nodes[0];
+		if (path->slots[0] >= btrfs_header_nritems(leaf)) {
+			ret = btrfs_next_leaf(tree_root, path);
+			if (ret < 0)
+				err = ret;
+			if (ret != 0)
+				break;
+			leaf = path->nodes[0];
+		}
+
+		btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
+		btrfs_release_path(tree_root, path);
+
+		if (key.objectid != BTRFS_ORPHAN_OBJECTID ||
+		    key.type != BTRFS_ORPHAN_ITEM_KEY)
+			break;
+
+		ret = btrfs_find_dead_roots(tree_root, key.offset);
+		if (ret) {
+			err = ret;
+			break;
+		}
+
+		key.offset++;
+	}
+
+	btrfs_free_path(path);
+	return err;
+}
+
 /* drop the root item for 'key' from 'root' */
 int btrfs_del_root(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 		   struct btrfs_key *key)
@@ -278,31 +337,57 @@ out:
 	return ret;
 }
 
-#if 0 /* this will get used when snapshot deletion is implemented */
 int btrfs_del_root_ref(struct btrfs_trans_handle *trans,
 		       struct btrfs_root *tree_root,
-		       u64 root_id, u8 type, u64 ref_id)
+		       u64 root_id, u64 ref_id, u64 dirid, u64 *sequence,
+		       const char *name, int name_len)
+
 {
+	struct btrfs_path *path;
+	struct btrfs_root_ref *ref;
+	struct extent_buffer *leaf;
 	struct btrfs_key key;
+	unsigned long ptr;
+	int err = 0;
 	int ret;
-	struct btrfs_path *path;
 
 	path = btrfs_alloc_path();
+	if (!path)
+		return -ENOMEM;
 
 	key.objectid = root_id;
-	key.type = type;
+	key.type = BTRFS_ROOT_BACKREF_KEY;
 	key.offset = ref_id;
-
+again:
 	ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1);
-	BUG_ON(ret);
-
-	ret = btrfs_del_item(trans, tree_root, path);
-	BUG_ON(ret);
+	BUG_ON(ret < 0);
+	if (ret == 0) {
+		leaf = path->nodes[0];
+		ref = btrfs_item_ptr(leaf, path->slots[0],
+				     struct btrfs_root_ref);
+
+		WARN_ON(btrfs_root_ref_dirid(leaf, ref) != dirid);
+		WARN_ON(btrfs_root_ref_name_len(leaf, ref) != name_len);
+		ptr = (unsigned long)(ref + 1);
+		WARN_ON(memcmp_extent_buffer(leaf, name, ptr, name_len));
+		*sequence = btrfs_root_ref_sequence(leaf, ref);
+
+		ret = btrfs_del_item(trans, tree_root, path);
+		BUG_ON(ret);
+	} else
+		err = -ENOENT;
+
+	if (key.type == BTRFS_ROOT_BACKREF_KEY) {
+		btrfs_release_path(tree_root, path);
+		key.objectid = ref_id;
+		key.type = BTRFS_ROOT_REF_KEY;
+		key.offset = root_id;
+		goto again;
+	}
 
 	btrfs_free_path(path);
-	return ret;
+	return err;
 }
-#endif
 
 int btrfs_find_root_ref(struct btrfs_root *tree_root,
 		   struct btrfs_path *path,
@@ -319,7 +404,6 @@ int btrfs_find_root_ref(struct btrfs_root *tree_root,
 	return ret;
 }
 
-
 /*
  * add a btrfs_root_ref item.  type is either BTRFS_ROOT_REF_KEY
  * or BTRFS_ROOT_BACKREF_KEY.
@@ -335,8 +419,7 @@ int btrfs_find_root_ref(struct btrfs_root *tree_root,
  */
 int btrfs_add_root_ref(struct btrfs_trans_handle *trans,
 		       struct btrfs_root *tree_root,
-		       u64 root_id, u8 type, u64 ref_id,
-		       u64 dirid, u64 sequence,
+		       u64 root_id, u64 ref_id, u64 dirid, u64 sequence,
 		       const char *name, int name_len)
 {
 	struct btrfs_key key;
@@ -346,13 +429,14 @@ int btrfs_add_root_ref(struct btrfs_trans_handle *trans,
 	struct extent_buffer *leaf;
 	unsigned long ptr;
 
-
 	path = btrfs_alloc_path();
+	if (!path)
+		return -ENOMEM;
 
 	key.objectid = root_id;
-	key.type = type;
+	key.type = BTRFS_ROOT_BACKREF_KEY;
 	key.offset = ref_id;
-
+again:
 	ret = btrfs_insert_empty_item(trans, tree_root, path, &key,
 				      sizeof(*ref) + name_len);
 	BUG_ON(ret);
@@ -366,6 +450,14 @@ int btrfs_add_root_ref(struct btrfs_trans_handle *trans,
 	write_extent_buffer(leaf, name, ptr, name_len);
 	btrfs_mark_buffer_dirty(leaf);
 
+	if (key.type == BTRFS_ROOT_BACKREF_KEY) {
+		btrfs_release_path(tree_root, path);
+		key.objectid = ref_id;
+		key.type = BTRFS_ROOT_REF_KEY;
+		key.offset = root_id;
+		goto again;
+	}
+
 	btrfs_free_path(path);
-	return ret;
+	return 0;
 }
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 2db17cd..752a546 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -66,7 +66,8 @@ enum {
 	Opt_degraded, Opt_subvol, Opt_device, Opt_nodatasum, Opt_nodatacow,
 	Opt_max_extent, Opt_max_inline, Opt_alloc_start, Opt_nobarrier,
 	Opt_ssd, Opt_nossd, Opt_ssd_spread, Opt_thread_pool, Opt_noacl,
-	Opt_compress, Opt_notreelog, Opt_ratio, Opt_flushoncommit, Opt_err,
+	Opt_compress, Opt_notreelog, Opt_ratio, Opt_flushoncommit,
+	Opt_discard, Opt_err,
 };
 
 static match_table_t tokens = {
@@ -88,6 +89,7 @@ static match_table_t tokens = {
 	{Opt_notreelog, "notreelog"},
 	{Opt_flushoncommit, "flushoncommit"},
 	{Opt_ratio, "metadata_ratio=%d"},
+	{Opt_discard, "discard"},
 	{Opt_err, NULL},
 };
 
@@ -257,6 +259,9 @@ int btrfs_parse_options(struct btrfs_root *root, char *options)
 				       info->metadata_ratio);
 			}
 			break;
+		case Opt_discard:
+			btrfs_set_opt(info->mount_opt, DISCARD);
+			break;
 		default:
 			break;
 		}
@@ -344,7 +349,9 @@ static int btrfs_fill_super(struct super_block *sb,
 	sb->s_export_op = &btrfs_export_ops;
 	sb->s_xattr = btrfs_xattr_handlers;
 	sb->s_time_gran = 1;
+#ifdef CONFIG_BTRFS_FS_POSIX_ACL
 	sb->s_flags |= MS_POSIXACL;
+#endif
 
 	tree_root = open_ctree(sb, fs_devices, (char *)data);
 
@@ -676,6 +683,7 @@ static int btrfs_unfreeze(struct super_block *sb)
 }
 
 static const struct super_operations btrfs_super_ops = {
+	.drop_inode	= btrfs_drop_inode,
 	.delete_inode	= btrfs_delete_inode,
 	.put_super	= btrfs_put_super,
 	.sync_fs	= btrfs_sync_fs,
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index cdbb502..bca82a4 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -104,7 +104,6 @@ static noinline int record_root_in_trans(struct btrfs_trans_handle *trans,
 {
 	if (root->ref_cows && root->last_trans < trans->transid) {
 		WARN_ON(root == root->fs_info->extent_root);
-		WARN_ON(root->root_item.refs == 0);
 		WARN_ON(root->commit_root != root->node);
 
 		radix_tree_tag_set(&root->fs_info->fs_roots_radix,
@@ -187,6 +186,9 @@ static struct btrfs_trans_handle *start_transaction(struct btrfs_root *root,
 	h->alloc_exclude_start = 0;
 	h->delayed_ref_updates = 0;
 
+	if (!current->journal_info)
+		current->journal_info = h;
+
 	root->fs_info->running_transaction->use_count++;
 	record_root_in_trans(h, root);
 	mutex_unlock(&root->fs_info->trans_mutex);
@@ -318,6 +320,9 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
 		wake_up(&cur_trans->writer_wait);
 	put_transaction(cur_trans);
 	mutex_unlock(&info->trans_mutex);
+
+	if (current->journal_info == trans)
+		current->journal_info = NULL;
 	memset(trans, 0, sizeof(*trans));
 	kmem_cache_free(btrfs_trans_handle_cachep, trans);
 
@@ -339,10 +344,10 @@ int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans,
 /*
  * when btree blocks are allocated, they have some corresponding bits set for
  * them in one of two extent_io trees.  This is used to make sure all of
- * those extents are on disk for transaction or log commit
+ * those extents are sent to disk but does not wait on them
  */
-int btrfs_write_and_wait_marked_extents(struct btrfs_root *root,
-					struct extent_io_tree *dirty_pages)
+int btrfs_write_marked_extents(struct btrfs_root *root,
+			       struct extent_io_tree *dirty_pages)
 {
 	int ret;
 	int err = 0;
@@ -389,6 +394,29 @@ int btrfs_write_and_wait_marked_extents(struct btrfs_root *root,
 			page_cache_release(page);
 		}
 	}
+	if (err)
+		werr = err;
+	return werr;
+}
+
+/*
+ * when btree blocks are allocated, they have some corresponding bits set for
+ * them in one of two extent_io trees.  This is used to make sure all of
+ * those extents are on disk for transaction or log commit.  We wait
+ * on all the pages and clear them from the dirty pages state tree
+ */
+int btrfs_wait_marked_extents(struct btrfs_root *root,
+			      struct extent_io_tree *dirty_pages)
+{
+	int ret;
+	int err = 0;
+	int werr = 0;
+	struct page *page;
+	struct inode *btree_inode = root->fs_info->btree_inode;
+	u64 start = 0;
+	u64 end;
+	unsigned long index;
+
 	while (1) {
 		ret = find_first_extent_bit(dirty_pages, 0, &start, &end,
 					    EXTENT_DIRTY);
@@ -419,6 +447,22 @@ int btrfs_write_and_wait_marked_extents(struct btrfs_root *root,
 	return werr;
 }
 
+/*
+ * when btree blocks are allocated, they have some corresponding bits set for
+ * them in one of two extent_io trees.  This is used to make sure all of
+ * those extents are on disk for transaction or log commit
+ */
+int btrfs_write_and_wait_marked_extents(struct btrfs_root *root,
+					struct extent_io_tree *dirty_pages)
+{
+	int ret;
+	int ret2;
+
+	ret = btrfs_write_marked_extents(root, dirty_pages);
+	ret2 = btrfs_wait_marked_extents(root, dirty_pages);
+	return ret || ret2;
+}
+
 int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans,
 				     struct btrfs_root *root)
 {
@@ -720,7 +764,8 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
 	memcpy(new_root_item, &root->root_item, sizeof(*new_root_item));
 
 	key.objectid = objectid;
-	key.offset = 0;
+	/* record when the snapshot was created in key.offset */
+	key.offset = trans->transid;
 	btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
 
 	old = btrfs_lock_root_node(root);
@@ -743,6 +788,7 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
 	memcpy(&pending->root_key, &key, sizeof(key));
 fail:
 	kfree(new_root_item);
+	btrfs_unreserve_metadata_space(root, 6);
 	return ret;
 }
 
@@ -778,24 +824,14 @@ static noinline int finish_pending_snapshot(struct btrfs_fs_info *fs_info,
 	ret = btrfs_update_inode(trans, parent_root, parent_inode);
 	BUG_ON(ret);
 
-	/* add the backref first */
 	ret = btrfs_add_root_ref(trans, parent_root->fs_info->tree_root,
 				 pending->root_key.objectid,
-				 BTRFS_ROOT_BACKREF_KEY,
 				 parent_root->root_key.objectid,
 				 parent_inode->i_ino, index, pending->name,
 				 namelen);
 
 	BUG_ON(ret);
 
-	/* now add the forward ref */
-	ret = btrfs_add_root_ref(trans, parent_root->fs_info->tree_root,
-				 parent_root->root_key.objectid,
-				 BTRFS_ROOT_REF_KEY,
-				 pending->root_key.objectid,
-				 parent_inode->i_ino, index, pending->name,
-				 namelen);
-
 	inode = btrfs_lookup_dentry(parent_inode, pending->dentry);
 	d_instantiate(pending->dentry, inode);
 fail:
@@ -874,7 +910,6 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
 	unsigned long timeout = 1;
 	struct btrfs_transaction *cur_trans;
 	struct btrfs_transaction *prev_trans = NULL;
-	struct extent_io_tree *pinned_copy;
 	DEFINE_WAIT(wait);
 	int ret;
 	int should_grow = 0;
@@ -915,13 +950,6 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
 		return 0;
 	}
 
-	pinned_copy = kmalloc(sizeof(*pinned_copy), GFP_NOFS);
-	if (!pinned_copy)
-		return -ENOMEM;
-
-	extent_io_tree_init(pinned_copy,
-			     root->fs_info->btree_inode->i_mapping, GFP_NOFS);
-
 	trans->transaction->in_commit = 1;
 	trans->transaction->blocked = 1;
 	if (cur_trans->list.prev != &root->fs_info->trans_list) {
@@ -1019,6 +1047,8 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
 	ret = commit_cowonly_roots(trans, root);
 	BUG_ON(ret);
 
+	btrfs_prepare_extent_commit(trans, root);
+
 	cur_trans = root->fs_info->running_transaction;
 	spin_lock(&root->fs_info->new_trans_lock);
 	root->fs_info->running_transaction = NULL;
@@ -1042,8 +1072,6 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
 	memcpy(&root->fs_info->super_for_commit, &root->fs_info->super_copy,
 	       sizeof(root->fs_info->super_copy));
 
-	btrfs_copy_pinned(root, pinned_copy);
-
 	trans->transaction->blocked = 0;
 
 	wake_up(&root->fs_info->transaction_wait);
@@ -1059,8 +1087,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
 	 */
 	mutex_unlock(&root->fs_info->tree_log_mutex);
 
-	btrfs_finish_extent_commit(trans, root, pinned_copy);
-	kfree(pinned_copy);
+	btrfs_finish_extent_commit(trans, root);
 
 	/* do the directory inserts of any pending snapshot creations */
 	finish_pending_snapshots(trans, root->fs_info);
@@ -1078,6 +1105,9 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
 
 	mutex_unlock(&root->fs_info->trans_mutex);
 
+	if (current->journal_info == trans)
+		current->journal_info = NULL;
+
 	kmem_cache_free(btrfs_trans_handle_cachep, trans);
 	return ret;
 }
@@ -1096,8 +1126,13 @@ int btrfs_clean_old_snapshots(struct btrfs_root *root)
 
 	while (!list_empty(&list)) {
 		root = list_entry(list.next, struct btrfs_root, root_list);
-		list_del_init(&root->root_list);
-		btrfs_drop_snapshot(root, 0);
+		list_del(&root->root_list);
+
+		if (btrfs_header_backref_rev(root->node) <
+		    BTRFS_MIXED_BACKREF_REV)
+			btrfs_drop_snapshot(root, 0);
+		else
+			btrfs_drop_snapshot(root, 1);
 	}
 	return 0;
 }
diff --git a/fs/btrfs/transaction.h b/fs/btrfs/transaction.h
index 663c674..d4e3e7a 100644
--- a/fs/btrfs/transaction.h
+++ b/fs/btrfs/transaction.h
@@ -79,6 +79,7 @@ static inline void btrfs_set_inode_last_trans(struct btrfs_trans_handle *trans,
 					      struct inode *inode)
 {
 	BTRFS_I(inode)->last_trans = trans->transaction->transid;
+	BTRFS_I(inode)->last_sub_trans = BTRFS_I(inode)->root->log_transid;
 }
 
 int btrfs_end_transaction(struct btrfs_trans_handle *trans,
@@ -107,5 +108,9 @@ int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans,
 				struct btrfs_root *root);
 int btrfs_write_and_wait_marked_extents(struct btrfs_root *root,
 					struct extent_io_tree *dirty_pages);
+int btrfs_write_marked_extents(struct btrfs_root *root,
+					struct extent_io_tree *dirty_pages);
+int btrfs_wait_marked_extents(struct btrfs_root *root,
+					struct extent_io_tree *dirty_pages);
 int btrfs_transaction_in_commit(struct btrfs_fs_info *info);
 #endif
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 30c0d45..741666a 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -137,11 +137,20 @@ static int start_log_trans(struct btrfs_trans_handle *trans,
 
 	mutex_lock(&root->log_mutex);
 	if (root->log_root) {
+		if (!root->log_start_pid) {
+			root->log_start_pid = current->pid;
+			root->log_multiple_pids = false;
+		} else if (root->log_start_pid != current->pid) {
+			root->log_multiple_pids = true;
+		}
+
 		root->log_batch++;
 		atomic_inc(&root->log_writers);
 		mutex_unlock(&root->log_mutex);
 		return 0;
 	}
+	root->log_multiple_pids = false;
+	root->log_start_pid = current->pid;
 	mutex_lock(&root->fs_info->tree_log_mutex);
 	if (!root->fs_info->log_root_tree) {
 		ret = btrfs_init_log_root_tree(trans, root->fs_info);
@@ -263,8 +272,8 @@ static int process_one_buffer(struct btrfs_root *log,
 			      struct walk_control *wc, u64 gen)
 {
 	if (wc->pin)
-		btrfs_update_pinned_extents(log->fs_info->extent_root,
-					    eb->start, eb->len, 1);
+		btrfs_pin_extent(log->fs_info->extent_root,
+				 eb->start, eb->len, 0);
 
 	if (btrfs_buffer_uptodate(eb, gen)) {
 		if (wc->write)
@@ -534,7 +543,7 @@ static noinline int replay_one_extent(struct btrfs_trans_handle *trans,
 	saved_nbytes = inode_get_bytes(inode);
 	/* drop any overlapping extents */
 	ret = btrfs_drop_extents(trans, root, inode,
-			 start, extent_end, extent_end, start, &alloc_hint);
+			 start, extent_end, extent_end, start, &alloc_hint, 1);
 	BUG_ON(ret);
 
 	if (found_type == BTRFS_FILE_EXTENT_REG ||
@@ -1971,6 +1980,7 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 	int ret;
 	struct btrfs_root *log = root->log_root;
 	struct btrfs_root *log_root_tree = root->fs_info->log_root_tree;
+	u64 log_transid = 0;
 
 	mutex_lock(&root->log_mutex);
 	index1 = root->log_transid % 2;
@@ -1987,10 +1997,11 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 
 	while (1) {
 		unsigned long batch = root->log_batch;
-		mutex_unlock(&root->log_mutex);
-		schedule_timeout_uninterruptible(1);
-		mutex_lock(&root->log_mutex);
-
+		if (root->log_multiple_pids) {
+			mutex_unlock(&root->log_mutex);
+			schedule_timeout_uninterruptible(1);
+			mutex_lock(&root->log_mutex);
+		}
 		wait_for_writer(trans, root);
 		if (batch == root->log_batch)
 			break;
@@ -2003,14 +2014,19 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 		goto out;
 	}
 
-	ret = btrfs_write_and_wait_marked_extents(log, &log->dirty_log_pages);
+	/* we start IO on  all the marked extents here, but we don't actually
+	 * wait for them until later.
+	 */
+	ret = btrfs_write_marked_extents(log, &log->dirty_log_pages);
 	BUG_ON(ret);
 
 	btrfs_set_root_node(&log->root_item, log->node);
 
 	root->log_batch = 0;
+	log_transid = root->log_transid;
 	root->log_transid++;
 	log->log_transid = root->log_transid;
+	root->log_start_pid = 0;
 	smp_mb();
 	/*
 	 * log tree has been flushed to disk, new modifications of
@@ -2036,6 +2052,7 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 
 	index2 = log_root_tree->log_transid % 2;
 	if (atomic_read(&log_root_tree->log_commit[index2])) {
+		btrfs_wait_marked_extents(log, &log->dirty_log_pages);
 		wait_log_commit(trans, log_root_tree,
 				log_root_tree->log_transid);
 		mutex_unlock(&log_root_tree->log_mutex);
@@ -2055,6 +2072,7 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 	 * check the full commit flag again
 	 */
 	if (root->fs_info->last_trans_log_full_commit == trans->transid) {
+		btrfs_wait_marked_extents(log, &log->dirty_log_pages);
 		mutex_unlock(&log_root_tree->log_mutex);
 		ret = -EAGAIN;
 		goto out_wake_log_root;
@@ -2063,6 +2081,7 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 	ret = btrfs_write_and_wait_marked_extents(log_root_tree,
 				&log_root_tree->dirty_log_pages);
 	BUG_ON(ret);
+	btrfs_wait_marked_extents(log, &log->dirty_log_pages);
 
 	btrfs_set_super_log_root(&root->fs_info->super_for_commit,
 				log_root_tree->node->start);
@@ -2082,9 +2101,14 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 	 * the running transaction open, so a full commit can't hop
 	 * in and cause problems either.
 	 */
-	write_ctree_super(trans, root->fs_info->tree_root, 2);
+	write_ctree_super(trans, root->fs_info->tree_root, 1);
 	ret = 0;
 
+	mutex_lock(&root->log_mutex);
+	if (root->last_log_commit < log_transid)
+		root->last_log_commit = log_transid;
+	mutex_unlock(&root->log_mutex);
+
 out_wake_log_root:
 	atomic_set(&log_root_tree->log_commit[index2], 0);
 	smp_mb();
@@ -2841,7 +2865,7 @@ static noinline int check_parent_dirs_for_sync(struct btrfs_trans_handle *trans,
 		if (!parent || !parent->d_inode || sb != parent->d_inode->i_sb)
 			break;
 
-		if (parent == sb->s_root)
+		if (IS_ROOT(parent))
 			break;
 
 		parent = parent->d_parent;
@@ -2852,6 +2876,21 @@ out:
 	return ret;
 }
 
+static int inode_in_log(struct btrfs_trans_handle *trans,
+		 struct inode *inode)
+{
+	struct btrfs_root *root = BTRFS_I(inode)->root;
+	int ret = 0;
+
+	mutex_lock(&root->log_mutex);
+	if (BTRFS_I(inode)->logged_trans == trans->transid &&
+	    BTRFS_I(inode)->last_sub_trans <= root->last_log_commit)
+		ret = 1;
+	mutex_unlock(&root->log_mutex);
+	return ret;
+}
+
+
 /*
  * helper function around btrfs_log_inode to make sure newly created
  * parent directories also end up in the log.  A minimal inode and backref
@@ -2880,11 +2919,22 @@ int btrfs_log_inode_parent(struct btrfs_trans_handle *trans,
 		goto end_no_trans;
 	}
 
+	if (root != BTRFS_I(inode)->root ||
+	    btrfs_root_refs(&root->root_item) == 0) {
+		ret = 1;
+		goto end_no_trans;
+	}
+
 	ret = check_parent_dirs_for_sync(trans, inode, parent,
 					 sb, last_committed);
 	if (ret)
 		goto end_no_trans;
 
+	if (inode_in_log(trans, inode)) {
+		ret = BTRFS_NO_LOG_SYNC;
+		goto end_no_trans;
+	}
+
 	start_log_trans(trans, root);
 
 	ret = btrfs_log_inode(trans, root, inode, inode_only);
@@ -2907,12 +2957,15 @@ int btrfs_log_inode_parent(struct btrfs_trans_handle *trans,
 			break;
 
 		inode = parent->d_inode;
+		if (root != BTRFS_I(inode)->root)
+			break;
+
 		if (BTRFS_I(inode)->generation >
 		    root->fs_info->last_trans_committed) {
 			ret = btrfs_log_inode(trans, root, inode, inode_only);
 			BUG_ON(ret);
 		}
-		if (parent == sb->s_root)
+		if (IS_ROOT(parent))
 			break;
 
 		parent = parent->d_parent;
@@ -2951,7 +3004,6 @@ int btrfs_recover_log_trees(struct btrfs_root *log_root_tree)
 	struct btrfs_key tmp_key;
 	struct btrfs_root *log;
 	struct btrfs_fs_info *fs_info = log_root_tree->fs_info;
-	u64 highest_inode;
 	struct walk_control wc = {
 		.process_func = process_one_buffer,
 		.stage = 0,
@@ -3010,11 +3062,6 @@ again:
 						      path);
 			BUG_ON(ret);
 		}
-		ret = btrfs_find_highest_inode(wc.replay_dest, &highest_inode);
-		if (ret == 0) {
-			wc.replay_dest->highest_inode = highest_inode;
-			wc.replay_dest->last_inode_alloc = highest_inode;
-		}
 
 		key.offset = found_key.offset - 1;
 		wc.replay_dest->log_root = NULL;
diff --git a/fs/btrfs/tree-log.h b/fs/btrfs/tree-log.h
index d09c760..0776eac 100644
--- a/fs/btrfs/tree-log.h
+++ b/fs/btrfs/tree-log.h
@@ -19,6 +19,9 @@
 #ifndef __TREE_LOG_
 #define __TREE_LOG_
 
+/* return value for btrfs_log_dentry_safe that means we don't need to log it at all */
+#define BTRFS_NO_LOG_SYNC 256
+
 int btrfs_sync_log(struct btrfs_trans_handle *trans,
 		   struct btrfs_root *root);
 int btrfs_free_log(struct btrfs_trans_handle *trans, struct btrfs_root *root);
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 5cf405b..7eda483 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -276,7 +276,7 @@ loop_lock:
 		 * is now congested.  Back off and let other work structs
 		 * run instead
 		 */
-		if (pending && bdi_write_congested(bdi) && batch_run > 32 &&
+		if (pending && bdi_write_congested(bdi) && batch_run > 8 &&
 		    fs_info->fs_devices->open_devices > 1) {
 			struct io_context *ioc;
 
@@ -446,8 +446,10 @@ static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig)
 			goto error;
 
 		device->name = kstrdup(orig_dev->name, GFP_NOFS);
-		if (!device->name)
+		if (!device->name) {
+			kfree(device);
 			goto error;
+		}
 
 		device->devid = orig_dev->devid;
 		device->work.func = pending_bios_fn;
@@ -719,10 +721,9 @@ error:
  * called very infrequently and that a given device has a small number
  * of extents
  */
-static noinline int find_free_dev_extent(struct btrfs_trans_handle *trans,
-					 struct btrfs_device *device,
-					 u64 num_bytes, u64 *start,
-					 u64 *max_avail)
+int find_free_dev_extent(struct btrfs_trans_handle *trans,
+			 struct btrfs_device *device, u64 num_bytes,
+			 u64 *start, u64 *max_avail)
 {
 	struct btrfs_key key;
 	struct btrfs_root *root = device->dev_root;
@@ -1736,6 +1737,10 @@ static int btrfs_relocate_chunk(struct btrfs_root *root,
 	extent_root = root->fs_info->extent_root;
 	em_tree = &root->fs_info->mapping_tree.map_tree;
 
+	ret = btrfs_can_relocate(extent_root, chunk_offset);
+	if (ret)
+		return -ENOSPC;
+
 	/* step one, relocate all the extents inside this chunk */
 	ret = btrfs_relocate_block_group(extent_root, chunk_offset);
 	BUG_ON(ret);
@@ -1749,9 +1754,9 @@ static int btrfs_relocate_chunk(struct btrfs_root *root,
 	 * step two, delete the device extents and the
 	 * chunk tree entries
 	 */
-	spin_lock(&em_tree->lock);
+	read_lock(&em_tree->lock);
 	em = lookup_extent_mapping(em_tree, chunk_offset, 1);
-	spin_unlock(&em_tree->lock);
+	read_unlock(&em_tree->lock);
 
 	BUG_ON(em->start > chunk_offset ||
 	       em->start + em->len < chunk_offset);
@@ -1780,9 +1785,9 @@ static int btrfs_relocate_chunk(struct btrfs_root *root,
 	ret = btrfs_remove_block_group(trans, extent_root, chunk_offset);
 	BUG_ON(ret);
 
-	spin_lock(&em_tree->lock);
+	write_lock(&em_tree->lock);
 	remove_extent_mapping(em_tree, em);
-	spin_unlock(&em_tree->lock);
+	write_unlock(&em_tree->lock);
 
 	kfree(map);
 	em->bdev = NULL;
@@ -1807,12 +1812,15 @@ static int btrfs_relocate_sys_chunks(struct btrfs_root *root)
 	struct btrfs_key found_key;
 	u64 chunk_tree = chunk_root->root_key.objectid;
 	u64 chunk_type;
+	bool retried = false;
+	int failed = 0;
 	int ret;
 
 	path = btrfs_alloc_path();
 	if (!path)
 		return -ENOMEM;
 
+again:
 	key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID;
 	key.offset = (u64)-1;
 	key.type = BTRFS_CHUNK_ITEM_KEY;
@@ -1842,7 +1850,10 @@ static int btrfs_relocate_sys_chunks(struct btrfs_root *root)
 			ret = btrfs_relocate_chunk(chunk_root, chunk_tree,
 						   found_key.objectid,
 						   found_key.offset);
-			BUG_ON(ret);
+			if (ret == -ENOSPC)
+				failed++;
+			else if (ret)
+				BUG();
 		}
 
 		if (found_key.offset == 0)
@@ -1850,6 +1861,14 @@ static int btrfs_relocate_sys_chunks(struct btrfs_root *root)
 		key.offset = found_key.offset - 1;
 	}
 	ret = 0;
+	if (failed && !retried) {
+		failed = 0;
+		retried = true;
+		goto again;
+	} else if (failed && retried) {
+		WARN_ON(1);
+		ret = -ENOSPC;
+	}
 error:
 	btrfs_free_path(path);
 	return ret;
@@ -1894,6 +1913,8 @@ int btrfs_balance(struct btrfs_root *dev_root)
 			continue;
 
 		ret = btrfs_shrink_device(device, old_size - size_to_free);
+		if (ret == -ENOSPC)
+			break;
 		BUG_ON(ret);
 
 		trans = btrfs_start_transaction(dev_root, 1);
@@ -1938,9 +1959,8 @@ int btrfs_balance(struct btrfs_root *dev_root)
 		chunk = btrfs_item_ptr(path->nodes[0],
 				       path->slots[0],
 				       struct btrfs_chunk);
-		key.offset = found_key.offset;
 		/* chunk zero is special */
-		if (key.offset == 0)
+		if (found_key.offset == 0)
 			break;
 
 		btrfs_release_path(chunk_root, path);
@@ -1948,7 +1968,8 @@ int btrfs_balance(struct btrfs_root *dev_root)
 					   chunk_root->root_key.objectid,
 					   found_key.objectid,
 					   found_key.offset);
-		BUG_ON(ret);
+		BUG_ON(ret && ret != -ENOSPC);
+		key.offset = found_key.offset - 1;
 	}
 	ret = 0;
 error:
@@ -1974,10 +1995,13 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
 	u64 chunk_offset;
 	int ret;
 	int slot;
+	int failed = 0;
+	bool retried = false;
 	struct extent_buffer *l;
 	struct btrfs_key key;
 	struct btrfs_super_block *super_copy = &root->fs_info->super_copy;
 	u64 old_total = btrfs_super_total_bytes(super_copy);
+	u64 old_size = device->total_bytes;
 	u64 diff = device->total_bytes - new_size;
 
 	if (new_size >= device->total_bytes)
@@ -1987,12 +2011,6 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
 	if (!path)
 		return -ENOMEM;
 
-	trans = btrfs_start_transaction(root, 1);
-	if (!trans) {
-		ret = -ENOMEM;
-		goto done;
-	}
-
 	path->reada = 2;
 
 	lock_chunks(root);
@@ -2001,8 +2019,8 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
 	if (device->writeable)
 		device->fs_devices->total_rw_bytes -= diff;
 	unlock_chunks(root);
-	btrfs_end_transaction(trans, root);
 
+again:
 	key.objectid = device->devid;
 	key.offset = (u64)-1;
 	key.type = BTRFS_DEV_EXTENT_KEY;
@@ -2017,6 +2035,7 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
 			goto done;
 		if (ret) {
 			ret = 0;
+			btrfs_release_path(root, path);
 			break;
 		}
 
@@ -2024,14 +2043,18 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
 		slot = path->slots[0];
 		btrfs_item_key_to_cpu(l, &key, path->slots[0]);
 
-		if (key.objectid != device->devid)
+		if (key.objectid != device->devid) {
+			btrfs_release_path(root, path);
 			break;
+		}
 
 		dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
 		length = btrfs_dev_extent_length(l, dev_extent);
 
-		if (key.offset + length <= new_size)
+		if (key.offset + length <= new_size) {
+			btrfs_release_path(root, path);
 			break;
+		}
 
 		chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent);
 		chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent);
@@ -2040,8 +2063,26 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size)
 
 		ret = btrfs_relocate_chunk(root, chunk_tree, chunk_objectid,
 					   chunk_offset);
-		if (ret)
+		if (ret && ret != -ENOSPC)
 			goto done;
+		if (ret == -ENOSPC)
+			failed++;
+		key.offset -= 1;
+	}
+
+	if (failed && !retried) {
+		failed = 0;
+		retried = true;
+		goto again;
+	} else if (failed && retried) {
+		ret = -ENOSPC;
+		lock_chunks(root);
+
+		device->total_bytes = old_size;
+		if (device->writeable)
+			device->fs_devices->total_rw_bytes += diff;
+		unlock_chunks(root);
+		goto done;
 	}
 
 	/* Shrinking succeeded, else we would be at "done". */
@@ -2294,9 +2335,9 @@ again:
 	em->block_len = em->len;
 
 	em_tree = &extent_root->fs_info->mapping_tree.map_tree;
-	spin_lock(&em_tree->lock);
+	write_lock(&em_tree->lock);
 	ret = add_extent_mapping(em_tree, em);
-	spin_unlock(&em_tree->lock);
+	write_unlock(&em_tree->lock);
 	BUG_ON(ret);
 	free_extent_map(em);
 
@@ -2491,9 +2532,9 @@ int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset)
 	int readonly = 0;
 	int i;
 
-	spin_lock(&map_tree->map_tree.lock);
+	read_lock(&map_tree->map_tree.lock);
 	em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1);
-	spin_unlock(&map_tree->map_tree.lock);
+	read_unlock(&map_tree->map_tree.lock);
 	if (!em)
 		return 1;
 
@@ -2518,11 +2559,11 @@ void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree)
 	struct extent_map *em;
 
 	while (1) {
-		spin_lock(&tree->map_tree.lock);
+		write_lock(&tree->map_tree.lock);
 		em = lookup_extent_mapping(&tree->map_tree, 0, (u64)-1);
 		if (em)
 			remove_extent_mapping(&tree->map_tree, em);
-		spin_unlock(&tree->map_tree.lock);
+		write_unlock(&tree->map_tree.lock);
 		if (!em)
 			break;
 		kfree(em->bdev);
@@ -2540,9 +2581,9 @@ int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len)
 	struct extent_map_tree *em_tree = &map_tree->map_tree;
 	int ret;
 
-	spin_lock(&em_tree->lock);
+	read_lock(&em_tree->lock);
 	em = lookup_extent_mapping(em_tree, logical, len);
-	spin_unlock(&em_tree->lock);
+	read_unlock(&em_tree->lock);
 	BUG_ON(!em);
 
 	BUG_ON(em->start > logical || em->start + em->len < logical);
@@ -2604,9 +2645,9 @@ again:
 		atomic_set(&multi->error, 0);
 	}
 
-	spin_lock(&em_tree->lock);
+	read_lock(&em_tree->lock);
 	em = lookup_extent_mapping(em_tree, logical, *length);
-	spin_unlock(&em_tree->lock);
+	read_unlock(&em_tree->lock);
 
 	if (!em && unplug_page)
 		return 0;
@@ -2763,9 +2804,9 @@ int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
 	u64 stripe_nr;
 	int i, j, nr = 0;
 
-	spin_lock(&em_tree->lock);
+	read_lock(&em_tree->lock);
 	em = lookup_extent_mapping(em_tree, chunk_start, 1);
-	spin_unlock(&em_tree->lock);
+	read_unlock(&em_tree->lock);
 
 	BUG_ON(!em || em->start != chunk_start);
 	map = (struct map_lookup *)em->bdev;
@@ -3053,9 +3094,9 @@ static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
 	logical = key->offset;
 	length = btrfs_chunk_length(leaf, chunk);
 
-	spin_lock(&map_tree->map_tree.lock);
+	read_lock(&map_tree->map_tree.lock);
 	em = lookup_extent_mapping(&map_tree->map_tree, logical, 1);
-	spin_unlock(&map_tree->map_tree.lock);
+	read_unlock(&map_tree->map_tree.lock);
 
 	/* already mapped? */
 	if (em && em->start <= logical && em->start + em->len > logical) {
@@ -3114,9 +3155,9 @@ static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
 		map->stripes[i].dev->in_fs_metadata = 1;
 	}
 
-	spin_lock(&map_tree->map_tree.lock);
+	write_lock(&map_tree->map_tree.lock);
 	ret = add_extent_mapping(&map_tree->map_tree, em);
-	spin_unlock(&map_tree->map_tree.lock);
+	write_unlock(&map_tree->map_tree.lock);
 	BUG_ON(ret);
 	free_extent_map(em);
 
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 5139a83..31b0fab 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -181,4 +181,7 @@ int btrfs_balance(struct btrfs_root *dev_root);
 void btrfs_unlock_volumes(void);
 void btrfs_lock_volumes(void);
 int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset);
+int find_free_dev_extent(struct btrfs_trans_handle *trans,
+			 struct btrfs_device *device, u64 num_bytes,
+			 u64 *start, u64 *max_avail);
 #endif
diff --git a/fs/btrfs/xattr.c b/fs/btrfs/xattr.c
index a9d3bf4..b6dd596 100644
--- a/fs/btrfs/xattr.c
+++ b/fs/btrfs/xattr.c
@@ -260,7 +260,7 @@ err:
  * attributes are handled directly.
  */
 struct xattr_handler *btrfs_xattr_handlers[] = {
-#ifdef CONFIG_FS_POSIX_ACL
+#ifdef CONFIG_BTRFS_FS_POSIX_ACL
 	&btrfs_xattr_acl_access_handler,
 	&btrfs_xattr_acl_default_handler,
 #endif
diff --git a/fs/buffer.c b/fs/buffer.c
index 209f7f1..6fa5302 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -280,7 +280,7 @@ void invalidate_bdev(struct block_device *bdev)
 EXPORT_SYMBOL(invalidate_bdev);
 
 /*
- * Kick pdflush then try to free up some ZONE_NORMAL memory.
+ * Kick the writeback threads then try to free up some ZONE_NORMAL memory.
  */
 static void free_more_memory(void)
 {
@@ -1709,9 +1709,9 @@ static int __block_write_full_page(struct inode *inode, struct page *page,
 		/*
 		 * If it's a fully non-blocking write attempt and we cannot
 		 * lock the buffer then redirty the page.  Note that this can
-		 * potentially cause a busy-wait loop from pdflush and kswapd
-		 * activity, but those code paths have their own higher-level
-		 * throttling.
+		 * potentially cause a busy-wait loop from writeback threads
+		 * and kswapd activity, but those code paths have their own
+		 * higher-level throttling.
 		 */
 		if (wbc->sync_mode != WB_SYNC_NONE || !wbc->nonblocking) {
 			lock_buffer(bh);
@@ -2239,16 +2239,10 @@ int generic_cont_expand_simple(struct inode *inode, loff_t size)
 	struct address_space *mapping = inode->i_mapping;
 	struct page *page;
 	void *fsdata;
-	unsigned long limit;
 	int err;
 
-	err = -EFBIG;
-        limit = current->signal->rlim[RLIMIT_FSIZE].rlim_cur;
-	if (limit != RLIM_INFINITY && size > (loff_t)limit) {
-		send_sig(SIGXFSZ, current, 0);
-		goto out;
-	}
-	if (size > inode->i_sb->s_maxbytes)
+	err = inode_newsize_ok(inode, size);
+	if (err)
 		goto out;
 
 	err = pagecache_write_begin(NULL, mapping, size, 0,
@@ -3214,7 +3208,7 @@ EXPORT_SYMBOL(block_sync_page);
  * still running obsolete flush daemons, so we terminate them here.
  *
  * Use of bdflush() is deprecated and will be removed in a future kernel.
- * The `pdflush' kernel threads fully replace bdflush daemons and this call.
+ * The `flush-X' kernel threads fully replace bdflush daemons and this call.
  */
 SYSCALL_DEFINE2(bdflush, int, func, long, data)
 {
diff --git a/fs/char_dev.c b/fs/char_dev.c
index 3cbc57f..d6db933 100644
--- a/fs/char_dev.c
+++ b/fs/char_dev.c
@@ -264,7 +264,6 @@ int __register_chrdev(unsigned int major, unsigned int baseminor,
 {
 	struct char_device_struct *cd;
 	struct cdev *cdev;
-	char *s;
 	int err = -ENOMEM;
 
 	cd = __register_chrdev_region(major, baseminor, count, name);
@@ -278,8 +277,6 @@ int __register_chrdev(unsigned int major, unsigned int baseminor,
 	cdev->owner = fops->owner;
 	cdev->ops = fops;
 	kobject_set_name(&cdev->kobj, "%s", name);
-	for (s = strchr(kobject_name(&cdev->kobj),'/'); s; s = strchr(s, '/'))
-		*s = '!';
 		
 	err = cdev_add(cdev, MKDEV(cd->major, baseminor), count);
 	if (err)
diff --git a/fs/cifs/Kconfig b/fs/cifs/Kconfig
index 6994a0f..80f3525 100644
--- a/fs/cifs/Kconfig
+++ b/fs/cifs/Kconfig
@@ -2,6 +2,7 @@ config CIFS
 	tristate "CIFS support (advanced network filesystem, SMBFS successor)"
 	depends on INET
 	select NLS
+	select SLOW_WORK
 	help
 	  This is the client VFS module for the Common Internet File System
 	  (CIFS) protocol which is the successor to the Server Message Block
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index d79ce2e..9a5e4f5 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -64,9 +64,6 @@ unsigned int multiuser_mount = 0;
 unsigned int extended_security = CIFSSEC_DEF;
 /* unsigned int ntlmv2_support = 0; */
 unsigned int sign_CIFS_PDUs = 1;
-extern struct task_struct *oplockThread; /* remove sparse warning */
-struct task_struct *oplockThread = NULL;
-/* extern struct task_struct * dnotifyThread; remove sparse warning */
 static const struct super_operations cifs_super_ops;
 unsigned int CIFSMaxBufSize = CIFS_MAX_MSGSIZE;
 module_param(CIFSMaxBufSize, int, 0);
@@ -185,8 +182,7 @@ out_mount_failed:
 			cifs_sb->mountdata = NULL;
 		}
 #endif
-		if (cifs_sb->local_nls)
-			unload_nls(cifs_sb->local_nls);
+		unload_nls(cifs_sb->local_nls);
 		kfree(cifs_sb);
 	}
 	return rc;
@@ -973,89 +969,12 @@ cifs_destroy_mids(void)
 	kmem_cache_destroy(cifs_oplock_cachep);
 }
 
-static int cifs_oplock_thread(void *dummyarg)
-{
-	struct oplock_q_entry *oplock_item;
-	struct cifsTconInfo *pTcon;
-	struct inode *inode;
-	__u16  netfid;
-	int rc, waitrc = 0;
-
-	set_freezable();
-	do {
-		if (try_to_freeze())
-			continue;
-
-		spin_lock(&cifs_oplock_lock);
-		if (list_empty(&cifs_oplock_list)) {
-			spin_unlock(&cifs_oplock_lock);
-			set_current_state(TASK_INTERRUPTIBLE);
-			schedule_timeout(39*HZ);
-		} else {
-			oplock_item = list_entry(cifs_oplock_list.next,
-						struct oplock_q_entry, qhead);
-			cFYI(1, ("found oplock item to write out"));
-			pTcon = oplock_item->tcon;
-			inode = oplock_item->pinode;
-			netfid = oplock_item->netfid;
-			spin_unlock(&cifs_oplock_lock);
-			DeleteOplockQEntry(oplock_item);
-			/* can not grab inode sem here since it would
-				deadlock when oplock received on delete
-				since vfs_unlink holds the i_mutex across
-				the call */
-			/* mutex_lock(&inode->i_mutex);*/
-			if (S_ISREG(inode->i_mode)) {
-#ifdef CONFIG_CIFS_EXPERIMENTAL
-				if (CIFS_I(inode)->clientCanCacheAll == 0)
-					break_lease(inode, FMODE_READ);
-				else if (CIFS_I(inode)->clientCanCacheRead == 0)
-					break_lease(inode, FMODE_WRITE);
-#endif
-				rc = filemap_fdatawrite(inode->i_mapping);
-				if (CIFS_I(inode)->clientCanCacheRead == 0) {
-					waitrc = filemap_fdatawait(
-							      inode->i_mapping);
-					invalidate_remote_inode(inode);
-				}
-				if (rc == 0)
-					rc = waitrc;
-			} else
-				rc = 0;
-			/* mutex_unlock(&inode->i_mutex);*/
-			if (rc)
-				CIFS_I(inode)->write_behind_rc = rc;
-			cFYI(1, ("Oplock flush inode %p rc %d",
-				inode, rc));
-
-				/* releasing stale oplock after recent reconnect
-				of smb session using a now incorrect file
-				handle is not a data integrity issue but do
-				not bother sending an oplock release if session
-				to server still is disconnected since oplock
-				already released by the server in that case */
-			if (!pTcon->need_reconnect) {
-				rc = CIFSSMBLock(0, pTcon, netfid,
-						0 /* len */ , 0 /* offset */, 0,
-						0, LOCKING_ANDX_OPLOCK_RELEASE,
-						false /* wait flag */);
-				cFYI(1, ("Oplock release rc = %d", rc));
-			}
-			set_current_state(TASK_INTERRUPTIBLE);
-			schedule_timeout(1);  /* yield in case q were corrupt */
-		}
-	} while (!kthread_should_stop());
-
-	return 0;
-}
-
 static int __init
 init_cifs(void)
 {
 	int rc = 0;
 	cifs_proc_init();
 	INIT_LIST_HEAD(&cifs_tcp_ses_list);
-	INIT_LIST_HEAD(&cifs_oplock_list);
 #ifdef CONFIG_CIFS_EXPERIMENTAL
 	INIT_LIST_HEAD(&GlobalDnotifyReqList);
 	INIT_LIST_HEAD(&GlobalDnotifyRsp_Q);
@@ -1084,7 +1003,6 @@ init_cifs(void)
 	rwlock_init(&GlobalSMBSeslock);
 	rwlock_init(&cifs_tcp_ses_lock);
 	spin_lock_init(&GlobalMid_Lock);
-	spin_lock_init(&cifs_oplock_lock);
 
 	if (cifs_max_pending < 2) {
 		cifs_max_pending = 2;
@@ -1119,16 +1037,13 @@ init_cifs(void)
 	if (rc)
 		goto out_unregister_key_type;
 #endif
-	oplockThread = kthread_run(cifs_oplock_thread, NULL, "cifsoplockd");
-	if (IS_ERR(oplockThread)) {
-		rc = PTR_ERR(oplockThread);
-		cERROR(1, ("error %d create oplock thread", rc));
-		goto out_unregister_dfs_key_type;
-	}
+	rc = slow_work_register_user();
+	if (rc)
+		goto out_unregister_resolver_key;
 
 	return 0;
 
- out_unregister_dfs_key_type:
+ out_unregister_resolver_key:
 #ifdef CONFIG_CIFS_DFS_UPCALL
 	unregister_key_type(&key_type_dns_resolver);
  out_unregister_key_type:
@@ -1165,7 +1080,6 @@ exit_cifs(void)
 	cifs_destroy_inodecache();
 	cifs_destroy_mids();
 	cifs_destroy_request_bufs();
-	kthread_stop(oplockThread);
 }
 
 MODULE_AUTHOR("Steve French <sfrench@us.ibm.com>");
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index 6cfc81a..5d0fde1 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -18,6 +18,7 @@
  */
 #include <linux/in.h>
 #include <linux/in6.h>
+#include <linux/slow-work.h>
 #include "cifs_fs_sb.h"
 #include "cifsacl.h"
 /*
@@ -346,14 +347,16 @@ struct cifsFileInfo {
 	/* lock scope id (0 if none) */
 	struct file *pfile; /* needed for writepage */
 	struct inode *pInode; /* needed for oplock break */
+	struct vfsmount *mnt;
 	struct mutex lock_mutex;
 	struct list_head llist; /* list of byte range locks we have. */
 	bool closePend:1;	/* file is marked to close */
 	bool invalidHandle:1;	/* file closed via session abend */
-	bool messageMode:1;	/* for pipes: message vs byte mode */
+	bool oplock_break_cancelled:1;
 	atomic_t count;		/* reference count */
 	struct mutex fh_mutex; /* prevents reopen race after dead ses*/
 	struct cifs_search_info srch_inf;
+	struct slow_work oplock_break; /* slow_work job for oplock breaks */
 };
 
 /* Take a reference on the file private data */
@@ -365,8 +368,10 @@ static inline void cifsFileInfo_get(struct cifsFileInfo *cifs_file)
 /* Release a reference on the file private data */
 static inline void cifsFileInfo_put(struct cifsFileInfo *cifs_file)
 {
-	if (atomic_dec_and_test(&cifs_file->count))
+	if (atomic_dec_and_test(&cifs_file->count)) {
+		iput(cifs_file->pInode);
 		kfree(cifs_file);
+	}
 }
 
 /*
@@ -382,7 +387,6 @@ struct cifsInodeInfo {
 	unsigned long time;	/* jiffies of last update/check of inode */
 	bool clientCanCacheRead:1;	/* read oplock */
 	bool clientCanCacheAll:1;	/* read and writebehind oplock */
-	bool oplockPending:1;
 	bool delete_pending:1;		/* DELETE_ON_CLOSE is set */
 	u64  server_eof;		/* current file size on server */
 	u64  uniqueid;			/* server inode number */
@@ -585,9 +589,9 @@ require use of the stronger protocol */
 #define   CIFSSEC_MUST_LANMAN	0x10010
 #define   CIFSSEC_MUST_PLNTXT	0x20020
 #ifdef CONFIG_CIFS_UPCALL
-#define   CIFSSEC_MASK          0xAF0AF /* allows weak security but also krb5 */
+#define   CIFSSEC_MASK          0xBF0BF /* allows weak security but also krb5 */
 #else
-#define   CIFSSEC_MASK          0xA70A7 /* current flags supported if weak */
+#define   CIFSSEC_MASK          0xB70B7 /* current flags supported if weak */
 #endif /* UPCALL */
 #else /* do not allow weak pw hash */
 #ifdef CONFIG_CIFS_UPCALL
@@ -669,12 +673,6 @@ GLOBAL_EXTERN rwlock_t		cifs_tcp_ses_lock;
  */
 GLOBAL_EXTERN rwlock_t GlobalSMBSeslock;
 
-/* Global list of oplocks */
-GLOBAL_EXTERN struct list_head cifs_oplock_list;
-
-/* Protects the cifs_oplock_list */
-GLOBAL_EXTERN spinlock_t cifs_oplock_lock;
-
 /* Outstanding dir notify requests */
 GLOBAL_EXTERN struct list_head GlobalDnotifyReqList;
 /* DirNotify response queue */
@@ -725,3 +723,4 @@ GLOBAL_EXTERN unsigned int cifs_min_rcv;    /* min size of big ntwrk buf pool */
 GLOBAL_EXTERN unsigned int cifs_min_small;  /* min size of small buf pool */
 GLOBAL_EXTERN unsigned int cifs_max_pending; /* MAX requests at once to server*/
 
+extern const struct slow_work_ops cifs_oplock_break_ops;
diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index da8fbf5..6928c24 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -86,18 +86,17 @@ extern int CIFS_SessSetup(unsigned int xid, struct cifsSesInfo *ses,
 			     const int stage,
 			     const struct nls_table *nls_cp);
 extern __u16 GetNextMid(struct TCP_Server_Info *server);
-extern struct oplock_q_entry *AllocOplockQEntry(struct inode *, u16,
-						 struct cifsTconInfo *);
-extern void DeleteOplockQEntry(struct oplock_q_entry *);
-extern void DeleteTconOplockQEntries(struct cifsTconInfo *);
 extern struct timespec cifs_NTtimeToUnix(__le64 utc_nanoseconds_since_1601);
 extern u64 cifs_UnixTimeToNT(struct timespec);
 extern struct timespec cnvrtDosUnixTm(__le16 le_date, __le16 le_time,
 				      int offset);
 
+extern struct cifsFileInfo *cifs_new_fileinfo(struct inode *newinode,
+				__u16 fileHandle, struct file *file,
+				struct vfsmount *mnt, unsigned int oflags);
 extern int cifs_posix_open(char *full_path, struct inode **pinode,
-			   struct super_block *sb, int mode, int oflags,
-			   int *poplock, __u16 *pnetfid, int xid);
+			   struct vfsmount *mnt, int mode, int oflags,
+			   __u32 *poplock, __u16 *pnetfid, int xid);
 extern void cifs_unix_basic_to_fattr(struct cifs_fattr *fattr,
 				     FILE_UNIX_BASIC_INFO *info,
 				     struct cifs_sb_info *cifs_sb);
diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c
index 301e307..941441d 100644
--- a/fs/cifs/cifssmb.c
+++ b/fs/cifs/cifssmb.c
@@ -94,6 +94,7 @@ static void mark_open_files_invalid(struct cifsTconInfo *pTcon)
 	list_for_each_safe(tmp, tmp1, &pTcon->openFileList) {
 		open_file = list_entry(tmp, struct cifsFileInfo, tlist);
 		open_file->invalidHandle = true;
+		open_file->oplock_break_cancelled = true;
 	}
 	write_unlock(&GlobalSMBSeslock);
 	/* BB Add call to invalidate_inodes(sb) for all superblocks mounted
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index d496824..43003e0 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -1670,7 +1670,6 @@ cifs_put_tcon(struct cifsTconInfo *tcon)
 	CIFSSMBTDis(xid, tcon);
 	_FreeXid(xid);
 
-	DeleteTconOplockQEntries(tcon);
 	tconInfoFree(tcon);
 	cifs_put_smb_ses(ses);
 }
diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c
index a6424cf..627a60a 100644
--- a/fs/cifs/dir.c
+++ b/fs/cifs/dir.c
@@ -24,6 +24,7 @@
 #include <linux/stat.h>
 #include <linux/slab.h>
 #include <linux/namei.h>
+#include <linux/mount.h>
 #include "cifsfs.h"
 #include "cifspdu.h"
 #include "cifsglob.h"
@@ -129,44 +130,45 @@ cifs_bp_rename_retry:
 	return full_path;
 }
 
-static void
-cifs_fill_fileinfo(struct inode *newinode, __u16 fileHandle,
-			struct cifsTconInfo *tcon, bool write_only)
+struct cifsFileInfo *
+cifs_new_fileinfo(struct inode *newinode, __u16 fileHandle,
+		  struct file *file, struct vfsmount *mnt, unsigned int oflags)
 {
 	int oplock = 0;
 	struct cifsFileInfo *pCifsFile;
 	struct cifsInodeInfo *pCifsInode;
+	struct cifs_sb_info *cifs_sb = CIFS_SB(mnt->mnt_sb);
 
 	pCifsFile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
-
 	if (pCifsFile == NULL)
-		return;
+		return pCifsFile;
 
 	if (oplockEnabled)
 		oplock = REQ_OPLOCK;
 
 	pCifsFile->netfid = fileHandle;
 	pCifsFile->pid = current->tgid;
-	pCifsFile->pInode = newinode;
+	pCifsFile->pInode = igrab(newinode);
+	pCifsFile->mnt = mnt;
+	pCifsFile->pfile = file;
 	pCifsFile->invalidHandle = false;
 	pCifsFile->closePend = false;
 	mutex_init(&pCifsFile->fh_mutex);
 	mutex_init(&pCifsFile->lock_mutex);
 	INIT_LIST_HEAD(&pCifsFile->llist);
 	atomic_set(&pCifsFile->count, 1);
+	slow_work_init(&pCifsFile->oplock_break, &cifs_oplock_break_ops);
 
-	/* set the following in open now
-			pCifsFile->pfile = file; */
 	write_lock(&GlobalSMBSeslock);
-	list_add(&pCifsFile->tlist, &tcon->openFileList);
+	list_add(&pCifsFile->tlist, &cifs_sb->tcon->openFileList);
 	pCifsInode = CIFS_I(newinode);
 	if (pCifsInode) {
 		/* if readable file instance put first in list*/
-		if (write_only)
+		if (oflags & FMODE_READ)
+			list_add(&pCifsFile->flist, &pCifsInode->openFileList);
+		else
 			list_add_tail(&pCifsFile->flist,
 				      &pCifsInode->openFileList);
-		else
-			list_add(&pCifsFile->flist, &pCifsInode->openFileList);
 
 		if ((oplock & 0xF) == OPLOCK_EXCLUSIVE) {
 			pCifsInode->clientCanCacheAll = true;
@@ -176,18 +178,18 @@ cifs_fill_fileinfo(struct inode *newinode, __u16 fileHandle,
 				pCifsInode->clientCanCacheRead = true;
 	}
 	write_unlock(&GlobalSMBSeslock);
+
+	return pCifsFile;
 }
 
 int cifs_posix_open(char *full_path, struct inode **pinode,
-		    struct super_block *sb, int mode, int oflags,
-		    int *poplock, __u16 *pnetfid, int xid)
+		    struct vfsmount *mnt, int mode, int oflags,
+		    __u32 *poplock, __u16 *pnetfid, int xid)
 {
 	int rc;
-	__u32 oplock;
-	bool write_only = false;
 	FILE_UNIX_BASIC_INFO *presp_data;
 	__u32 posix_flags = 0;
-	struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
+	struct cifs_sb_info *cifs_sb = CIFS_SB(mnt->mnt_sb);
 	struct cifs_fattr fattr;
 
 	cFYI(1, ("posix open %s", full_path));
@@ -223,12 +225,9 @@ int cifs_posix_open(char *full_path, struct inode **pinode,
 	if (oflags & O_DIRECT)
 		posix_flags |= SMB_O_DIRECT;
 
-	if (!(oflags & FMODE_READ))
-		write_only = true;
-
 	mode &= ~current_umask();
 	rc = CIFSPOSIXCreate(xid, cifs_sb->tcon, posix_flags, mode,
-			pnetfid, presp_data, &oplock, full_path,
+			pnetfid, presp_data, poplock, full_path,
 			cifs_sb->local_nls, cifs_sb->mnt_cifs_flags &
 					CIFS_MOUNT_MAP_SPECIAL_CHR);
 	if (rc)
@@ -244,7 +243,7 @@ int cifs_posix_open(char *full_path, struct inode **pinode,
 
 	/* get new inode and set it up */
 	if (*pinode == NULL) {
-		*pinode = cifs_iget(sb, &fattr);
+		*pinode = cifs_iget(mnt->mnt_sb, &fattr);
 		if (!*pinode) {
 			rc = -ENOMEM;
 			goto posix_open_ret;
@@ -253,7 +252,7 @@ int cifs_posix_open(char *full_path, struct inode **pinode,
 		cifs_fattr_to_inode(*pinode, &fattr);
 	}
 
-	cifs_fill_fileinfo(*pinode, *pnetfid, cifs_sb->tcon, write_only);
+	cifs_new_fileinfo(*pinode, *pnetfid, NULL, mnt, oflags);
 
 posix_open_ret:
 	kfree(presp_data);
@@ -280,7 +279,7 @@ cifs_create(struct inode *inode, struct dentry *direntry, int mode,
 	int rc = -ENOENT;
 	int xid;
 	int create_options = CREATE_NOT_DIR;
-	int oplock = 0;
+	__u32 oplock = 0;
 	int oflags;
 	bool posix_create = false;
 	/*
@@ -298,7 +297,6 @@ cifs_create(struct inode *inode, struct dentry *direntry, int mode,
 	FILE_ALL_INFO *buf = NULL;
 	struct inode *newinode = NULL;
 	int disposition = FILE_OVERWRITE_IF;
-	bool write_only = false;
 
 	xid = GetXid();
 
@@ -323,7 +321,7 @@ cifs_create(struct inode *inode, struct dentry *direntry, int mode,
 	if (tcon->unix_ext && (tcon->ses->capabilities & CAP_UNIX) &&
 	    (CIFS_UNIX_POSIX_PATH_OPS_CAP &
 			le64_to_cpu(tcon->fsUnixInfo.Capability))) {
-		rc = cifs_posix_open(full_path, &newinode, inode->i_sb,
+		rc = cifs_posix_open(full_path, &newinode, nd->path.mnt,
 				     mode, oflags, &oplock, &fileHandle, xid);
 		/* EIO could indicate that (posix open) operation is not
 		   supported, despite what server claimed in capability
@@ -351,11 +349,8 @@ cifs_create(struct inode *inode, struct dentry *direntry, int mode,
 		desiredAccess = 0;
 		if (oflags & FMODE_READ)
 			desiredAccess |= GENERIC_READ; /* is this too little? */
-		if (oflags & FMODE_WRITE) {
+		if (oflags & FMODE_WRITE)
 			desiredAccess |= GENERIC_WRITE;
-			if (!(oflags & FMODE_READ))
-				write_only = true;
-		}
 
 		if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
 			disposition = FILE_CREATE;
@@ -470,8 +465,8 @@ cifs_create_set_dentry:
 		/* mknod case - do not leave file open */
 		CIFSSMBClose(xid, tcon, fileHandle);
 	} else if (!(posix_create) && (newinode)) {
-			cifs_fill_fileinfo(newinode, fileHandle,
-					cifs_sb->tcon, write_only);
+			cifs_new_fileinfo(newinode, fileHandle, NULL,
+						nd->path.mnt, oflags);
 	}
 cifs_create_out:
 	kfree(buf);
@@ -611,7 +606,7 @@ cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
 {
 	int xid;
 	int rc = 0; /* to get around spurious gcc warning, set to zero here */
-	int oplock = 0;
+	__u32 oplock = 0;
 	__u16 fileHandle = 0;
 	bool posix_open = false;
 	struct cifs_sb_info *cifs_sb;
@@ -683,8 +678,7 @@ cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
 		if (!(nd->flags & (LOOKUP_PARENT | LOOKUP_DIRECTORY)) &&
 		     (nd->flags & LOOKUP_OPEN) && !pTcon->broken_posix_open &&
 		     (nd->intent.open.flags & O_CREAT)) {
-			rc = cifs_posix_open(full_path, &newInode,
-					parent_dir_inode->i_sb,
+			rc = cifs_posix_open(full_path, &newInode, nd->path.mnt,
 					nd->intent.open.create_mode,
 					nd->intent.open.flags, &oplock,
 					&fileHandle, xid);
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index fa7beac..429337e 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -30,6 +30,7 @@
 #include <linux/writeback.h>
 #include <linux/task_io_accounting_ops.h>
 #include <linux/delay.h>
+#include <linux/mount.h>
 #include <asm/div64.h>
 #include "cifsfs.h"
 #include "cifspdu.h"
@@ -39,27 +40,6 @@
 #include "cifs_debug.h"
 #include "cifs_fs_sb.h"
 
-static inline struct cifsFileInfo *cifs_init_private(
-	struct cifsFileInfo *private_data, struct inode *inode,
-	struct file *file, __u16 netfid)
-{
-	memset(private_data, 0, sizeof(struct cifsFileInfo));
-	private_data->netfid = netfid;
-	private_data->pid = current->tgid;
-	mutex_init(&private_data->fh_mutex);
-	mutex_init(&private_data->lock_mutex);
-	INIT_LIST_HEAD(&private_data->llist);
-	private_data->pfile = file; /* needed for writepage */
-	private_data->pInode = inode;
-	private_data->invalidHandle = false;
-	private_data->closePend = false;
-	/* Initialize reference count to one.  The private data is
-	freed on the release of the last reference */
-	atomic_set(&private_data->count, 1);
-
-	return private_data;
-}
-
 static inline int cifs_convert_flags(unsigned int flags)
 {
 	if ((flags & O_ACCMODE) == O_RDONLY)
@@ -123,9 +103,11 @@ static inline int cifs_get_disposition(unsigned int flags)
 }
 
 /* all arguments to this function must be checked for validity in caller */
-static inline int cifs_posix_open_inode_helper(struct inode *inode,
-			struct file *file, struct cifsInodeInfo *pCifsInode,
-			struct cifsFileInfo *pCifsFile, int oplock, u16 netfid)
+static inline int
+cifs_posix_open_inode_helper(struct inode *inode, struct file *file,
+			     struct cifsInodeInfo *pCifsInode,
+			     struct cifsFileInfo *pCifsFile, __u32 oplock,
+			     u16 netfid)
 {
 
 	write_lock(&GlobalSMBSeslock);
@@ -219,17 +201,6 @@ static inline int cifs_open_inode_helper(struct inode *inode, struct file *file,
 	struct timespec temp;
 	int rc;
 
-	/* want handles we can use to read with first
-	   in the list so we do not have to walk the
-	   list to search for one in write_begin */
-	if ((file->f_flags & O_ACCMODE) == O_WRONLY) {
-		list_add_tail(&pCifsFile->flist,
-			      &pCifsInode->openFileList);
-	} else {
-		list_add(&pCifsFile->flist,
-			 &pCifsInode->openFileList);
-	}
-	write_unlock(&GlobalSMBSeslock);
 	if (pCifsInode->clientCanCacheRead) {
 		/* we have the inode open somewhere else
 		   no need to discard cache data */
@@ -279,7 +250,8 @@ client_can_cache:
 int cifs_open(struct inode *inode, struct file *file)
 {
 	int rc = -EACCES;
-	int xid, oplock;
+	int xid;
+	__u32 oplock;
 	struct cifs_sb_info *cifs_sb;
 	struct cifsTconInfo *tcon;
 	struct cifsFileInfo *pCifsFile;
@@ -324,7 +296,7 @@ int cifs_open(struct inode *inode, struct file *file)
 			le64_to_cpu(tcon->fsUnixInfo.Capability))) {
 		int oflags = (int) cifs_posix_convert_flags(file->f_flags);
 		/* can not refresh inode info since size could be stale */
-		rc = cifs_posix_open(full_path, &inode, inode->i_sb,
+		rc = cifs_posix_open(full_path, &inode, file->f_path.mnt,
 				     cifs_sb->mnt_file_mode /* ignored */,
 				     oflags, &oplock, &netfid, xid);
 		if (rc == 0) {
@@ -414,24 +386,17 @@ int cifs_open(struct inode *inode, struct file *file)
 		cFYI(1, ("cifs_open returned 0x%x", rc));
 		goto out;
 	}
-	file->private_data =
-		kmalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
+
+	pCifsFile = cifs_new_fileinfo(inode, netfid, file, file->f_path.mnt,
+					file->f_flags);
+	file->private_data = pCifsFile;
 	if (file->private_data == NULL) {
 		rc = -ENOMEM;
 		goto out;
 	}
-	pCifsFile = cifs_init_private(file->private_data, inode, file, netfid);
-	write_lock(&GlobalSMBSeslock);
-	list_add(&pCifsFile->tlist, &tcon->openFileList);
 
-	pCifsInode = CIFS_I(file->f_path.dentry->d_inode);
-	if (pCifsInode) {
-		rc = cifs_open_inode_helper(inode, file, pCifsInode,
-					    pCifsFile, tcon,
-					    &oplock, buf, full_path, xid);
-	} else {
-		write_unlock(&GlobalSMBSeslock);
-	}
+	rc = cifs_open_inode_helper(inode, file, pCifsInode, pCifsFile, tcon,
+				    &oplock, buf, full_path, xid);
 
 	if (oplock & CIFS_CREATE_ACTION) {
 		/* time to set mode which we can not set earlier due to
@@ -474,7 +439,8 @@ static int cifs_relock_file(struct cifsFileInfo *cifsFile)
 static int cifs_reopen_file(struct file *file, bool can_flush)
 {
 	int rc = -EACCES;
-	int xid, oplock;
+	int xid;
+	__u32 oplock;
 	struct cifs_sb_info *cifs_sb;
 	struct cifsTconInfo *tcon;
 	struct cifsFileInfo *pCifsFile;
@@ -543,7 +509,7 @@ reopen_error_exit:
 			le64_to_cpu(tcon->fsUnixInfo.Capability))) {
 		int oflags = (int) cifs_posix_convert_flags(file->f_flags);
 		/* can not refresh inode info since size could be stale */
-		rc = cifs_posix_open(full_path, NULL, inode->i_sb,
+		rc = cifs_posix_open(full_path, NULL, file->f_path.mnt,
 				     cifs_sb->mnt_file_mode /* ignored */,
 				     oflags, &oplock, &netfid, xid);
 		if (rc == 0) {
@@ -2308,6 +2274,73 @@ out:
 	return rc;
 }
 
+static void
+cifs_oplock_break(struct slow_work *work)
+{
+	struct cifsFileInfo *cfile = container_of(work, struct cifsFileInfo,
+						  oplock_break);
+	struct inode *inode = cfile->pInode;
+	struct cifsInodeInfo *cinode = CIFS_I(inode);
+	struct cifs_sb_info *cifs_sb = CIFS_SB(cfile->mnt->mnt_sb);
+	int rc, waitrc = 0;
+
+	if (inode && S_ISREG(inode->i_mode)) {
+#ifdef CONFIG_CIFS_EXPERIMENTAL
+		if (cinode->clientCanCacheAll == 0)
+			break_lease(inode, FMODE_READ);
+		else if (cinode->clientCanCacheRead == 0)
+			break_lease(inode, FMODE_WRITE);
+#endif
+		rc = filemap_fdatawrite(inode->i_mapping);
+		if (cinode->clientCanCacheRead == 0) {
+			waitrc = filemap_fdatawait(inode->i_mapping);
+			invalidate_remote_inode(inode);
+		}
+		if (!rc)
+			rc = waitrc;
+		if (rc)
+			cinode->write_behind_rc = rc;
+		cFYI(1, ("Oplock flush inode %p rc %d", inode, rc));
+	}
+
+	/*
+	 * releasing stale oplock after recent reconnect of smb session using
+	 * a now incorrect file handle is not a data integrity issue but do
+	 * not bother sending an oplock release if session to server still is
+	 * disconnected since oplock already released by the server
+	 */
+	if (!cfile->closePend && !cfile->oplock_break_cancelled) {
+		rc = CIFSSMBLock(0, cifs_sb->tcon, cfile->netfid, 0, 0, 0, 0,
+				 LOCKING_ANDX_OPLOCK_RELEASE, false);
+		cFYI(1, ("Oplock release rc = %d", rc));
+	}
+}
+
+static int
+cifs_oplock_break_get(struct slow_work *work)
+{
+	struct cifsFileInfo *cfile = container_of(work, struct cifsFileInfo,
+						  oplock_break);
+	mntget(cfile->mnt);
+	cifsFileInfo_get(cfile);
+	return 0;
+}
+
+static void
+cifs_oplock_break_put(struct slow_work *work)
+{
+	struct cifsFileInfo *cfile = container_of(work, struct cifsFileInfo,
+						  oplock_break);
+	mntput(cfile->mnt);
+	cifsFileInfo_put(cfile);
+}
+
+const struct slow_work_ops cifs_oplock_break_ops = {
+	.get_ref	= cifs_oplock_break_get,
+	.put_ref	= cifs_oplock_break_put,
+	.execute	= cifs_oplock_break,
+};
+
 const struct address_space_operations cifs_addr_ops = {
 	.readpage = cifs_readpage,
 	.readpages = cifs_readpages,
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 1f09c76..5e24925 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -1557,57 +1557,24 @@ static int cifs_truncate_page(struct address_space *mapping, loff_t from)
 
 static int cifs_vmtruncate(struct inode *inode, loff_t offset)
 {
-	struct address_space *mapping = inode->i_mapping;
-	unsigned long limit;
+	loff_t oldsize;
+	int err;
 
 	spin_lock(&inode->i_lock);
-	if (inode->i_size < offset)
-		goto do_expand;
-	/*
-	 * truncation of in-use swapfiles is disallowed - it would cause
-	 * subsequent swapout to scribble on the now-freed blocks.
-	 */
-	if (IS_SWAPFILE(inode)) {
-		spin_unlock(&inode->i_lock);
-		goto out_busy;
-	}
-	i_size_write(inode, offset);
-	spin_unlock(&inode->i_lock);
-	/*
-	 * unmap_mapping_range is called twice, first simply for efficiency
-	 * so that truncate_inode_pages does fewer single-page unmaps. However
-	 * after this first call, and before truncate_inode_pages finishes,
-	 * it is possible for private pages to be COWed, which remain after
-	 * truncate_inode_pages finishes, hence the second unmap_mapping_range
-	 * call must be made for correctness.
-	 */
-	unmap_mapping_range(mapping, offset + PAGE_SIZE - 1, 0, 1);
-	truncate_inode_pages(mapping, offset);
-	unmap_mapping_range(mapping, offset + PAGE_SIZE - 1, 0, 1);
-	goto out_truncate;
-
-do_expand:
-	limit = current->signal->rlim[RLIMIT_FSIZE].rlim_cur;
-	if (limit != RLIM_INFINITY && offset > limit) {
+	err = inode_newsize_ok(inode, offset);
+	if (err) {
 		spin_unlock(&inode->i_lock);
-		goto out_sig;
-	}
-	if (offset > inode->i_sb->s_maxbytes) {
-		spin_unlock(&inode->i_lock);
-		goto out_big;
+		goto out;
 	}
+
+	oldsize = inode->i_size;
 	i_size_write(inode, offset);
 	spin_unlock(&inode->i_lock);
-out_truncate:
+	truncate_pagecache(inode, oldsize, offset);
 	if (inode->i_op->truncate)
 		inode->i_op->truncate(inode);
-	return 0;
-out_sig:
-	send_sig(SIGXFSZ, current, 0);
-out_big:
-	return -EFBIG;
-out_busy:
-	return -ETXTBSY;
+out:
+	return err;
 }
 
 static int
diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c
index e079a91..0241b25 100644
--- a/fs/cifs/misc.c
+++ b/fs/cifs/misc.c
@@ -32,7 +32,6 @@
 
 extern mempool_t *cifs_sm_req_poolp;
 extern mempool_t *cifs_req_poolp;
-extern struct task_struct *oplockThread;
 
 /* The xid serves as a useful identifier for each incoming vfs request,
    in a similar way to the mid which is useful to track each sent smb,
@@ -500,6 +499,7 @@ is_valid_oplock_break(struct smb_hdr *buf, struct TCP_Server_Info *srv)
 	struct cifsTconInfo *tcon;
 	struct cifsInodeInfo *pCifsInode;
 	struct cifsFileInfo *netfile;
+	int rc;
 
 	cFYI(1, ("Checking for oplock break or dnotify response"));
 	if ((pSMB->hdr.Command == SMB_COM_NT_TRANSACT) &&
@@ -562,30 +562,40 @@ is_valid_oplock_break(struct smb_hdr *buf, struct TCP_Server_Info *srv)
 				continue;
 
 			cifs_stats_inc(&tcon->num_oplock_brks);
-			write_lock(&GlobalSMBSeslock);
+			read_lock(&GlobalSMBSeslock);
 			list_for_each(tmp2, &tcon->openFileList) {
 				netfile = list_entry(tmp2, struct cifsFileInfo,
 						     tlist);
 				if (pSMB->Fid != netfile->netfid)
 					continue;
 
-				write_unlock(&GlobalSMBSeslock);
-				read_unlock(&cifs_tcp_ses_lock);
+				/*
+				 * don't do anything if file is about to be
+				 * closed anyway.
+				 */
+				if (netfile->closePend) {
+					read_unlock(&GlobalSMBSeslock);
+					read_unlock(&cifs_tcp_ses_lock);
+					return true;
+				}
+
 				cFYI(1, ("file id match, oplock break"));
 				pCifsInode = CIFS_I(netfile->pInode);
 				pCifsInode->clientCanCacheAll = false;
 				if (pSMB->OplockLevel == 0)
 					pCifsInode->clientCanCacheRead = false;
-				pCifsInode->oplockPending = true;
-				AllocOplockQEntry(netfile->pInode,
-						  netfile->netfid, tcon);
-				cFYI(1, ("about to wake up oplock thread"));
-				if (oplockThread)
-					wake_up_process(oplockThread);
-
+				rc = slow_work_enqueue(&netfile->oplock_break);
+				if (rc) {
+					cERROR(1, ("failed to enqueue oplock "
+						   "break: %d\n", rc));
+				} else {
+					netfile->oplock_break_cancelled = false;
+				}
+				read_unlock(&GlobalSMBSeslock);
+				read_unlock(&cifs_tcp_ses_lock);
 				return true;
 			}
-			write_unlock(&GlobalSMBSeslock);
+			read_unlock(&GlobalSMBSeslock);
 			read_unlock(&cifs_tcp_ses_lock);
 			cFYI(1, ("No matching file for oplock break"));
 			return true;
diff --git a/fs/cifs/readdir.c b/fs/cifs/readdir.c
index f823a4a..1f098ca 100644
--- a/fs/cifs/readdir.c
+++ b/fs/cifs/readdir.c
@@ -146,7 +146,7 @@ cifs_fill_common_info(struct cifs_fattr *fattr, struct cifs_sb_info *cifs_sb)
 	}
 }
 
-void
+static void
 cifs_dir_info_to_fattr(struct cifs_fattr *fattr, FILE_DIRECTORY_INFO *info,
 		       struct cifs_sb_info *cifs_sb)
 {
@@ -161,7 +161,7 @@ cifs_dir_info_to_fattr(struct cifs_fattr *fattr, FILE_DIRECTORY_INFO *info,
 	cifs_fill_common_info(fattr, cifs_sb);
 }
 
-void
+static void
 cifs_std_info_to_fattr(struct cifs_fattr *fattr, FIND_FILE_STANDARD_INFO *info,
 		       struct cifs_sb_info *cifs_sb)
 {
diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
index 1da4ab2..07b8e71 100644
--- a/fs/cifs/transport.c
+++ b/fs/cifs/transport.c
@@ -103,56 +103,6 @@ DeleteMidQEntry(struct mid_q_entry *midEntry)
 	mempool_free(midEntry, cifs_mid_poolp);
 }
 
-struct oplock_q_entry *
-AllocOplockQEntry(struct inode *pinode, __u16 fid, struct cifsTconInfo *tcon)
-{
-	struct oplock_q_entry *temp;
-	if ((pinode == NULL) || (tcon == NULL)) {
-		cERROR(1, ("Null parms passed to AllocOplockQEntry"));
-		return NULL;
-	}
-	temp = (struct oplock_q_entry *) kmem_cache_alloc(cifs_oplock_cachep,
-						       GFP_KERNEL);
-	if (temp == NULL)
-		return temp;
-	else {
-		temp->pinode = pinode;
-		temp->tcon = tcon;
-		temp->netfid = fid;
-		spin_lock(&cifs_oplock_lock);
-		list_add_tail(&temp->qhead, &cifs_oplock_list);
-		spin_unlock(&cifs_oplock_lock);
-	}
-	return temp;
-}
-
-void DeleteOplockQEntry(struct oplock_q_entry *oplockEntry)
-{
-	spin_lock(&cifs_oplock_lock);
-    /* should we check if list empty first? */
-	list_del(&oplockEntry->qhead);
-	spin_unlock(&cifs_oplock_lock);
-	kmem_cache_free(cifs_oplock_cachep, oplockEntry);
-}
-
-
-void DeleteTconOplockQEntries(struct cifsTconInfo *tcon)
-{
-	struct oplock_q_entry *temp;
-
-	if (tcon == NULL)
-		return;
-
-	spin_lock(&cifs_oplock_lock);
-	list_for_each_entry(temp, &cifs_oplock_list, qhead) {
-		if ((temp->tcon) && (temp->tcon == tcon)) {
-			list_del(&temp->qhead);
-			kmem_cache_free(cifs_oplock_cachep, temp);
-		}
-	}
-	spin_unlock(&cifs_oplock_lock);
-}
-
 static int
 smb_sendv(struct TCP_Server_Info *server, struct kvec *iov, int n_vec)
 {
diff --git a/fs/coda/coda_int.h b/fs/coda/coda_int.h
index 8ccd5ed..d99860a 100644
--- a/fs/coda/coda_int.h
+++ b/fs/coda/coda_int.h
@@ -2,6 +2,7 @@
 #define _CODA_INT_
 
 struct dentry;
+struct file;
 
 extern struct file_system_type coda_fs_type;
 extern unsigned long coda_timeout;
diff --git a/fs/coda/psdev.c b/fs/coda/psdev.c
index 0376ac6..be4392c 100644
--- a/fs/coda/psdev.c
+++ b/fs/coda/psdev.c
@@ -22,6 +22,7 @@
 #include <linux/kernel.h>
 #include <linux/major.h>
 #include <linux/time.h>
+#include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/ioport.h>
 #include <linux/fcntl.h>
diff --git a/fs/compat.c b/fs/compat.c
index 3aa4883..d576b55 100644
--- a/fs/compat.c
+++ b/fs/compat.c
@@ -768,13 +768,13 @@ asmlinkage long compat_sys_mount(char __user * dev_name, char __user * dir_name,
 				 char __user * type, unsigned long flags,
 				 void __user * data)
 {
-	unsigned long type_page;
+	char *kernel_type;
 	unsigned long data_page;
-	unsigned long dev_page;
+	char *kernel_dev;
 	char *dir_page;
 	int retval;
 
-	retval = copy_mount_options (type, &type_page);
+	retval = copy_mount_string(type, &kernel_type);
 	if (retval < 0)
 		goto out;
 
@@ -783,38 +783,38 @@ asmlinkage long compat_sys_mount(char __user * dev_name, char __user * dir_name,
 	if (IS_ERR(dir_page))
 		goto out1;
 
-	retval = copy_mount_options (dev_name, &dev_page);
+	retval = copy_mount_string(dev_name, &kernel_dev);
 	if (retval < 0)
 		goto out2;
 
-	retval = copy_mount_options (data, &data_page);
+	retval = copy_mount_options(data, &data_page);
 	if (retval < 0)
 		goto out3;
 
 	retval = -EINVAL;
 
-	if (type_page && data_page) {
-		if (!strcmp((char *)type_page, SMBFS_NAME)) {
+	if (kernel_type && data_page) {
+		if (!strcmp(kernel_type, SMBFS_NAME)) {
 			do_smb_super_data_conv((void *)data_page);
-		} else if (!strcmp((char *)type_page, NCPFS_NAME)) {
+		} else if (!strcmp(kernel_type, NCPFS_NAME)) {
 			do_ncp_super_data_conv((void *)data_page);
-		} else if (!strcmp((char *)type_page, NFS4_NAME)) {
+		} else if (!strcmp(kernel_type, NFS4_NAME)) {
 			if (do_nfs4_super_data_conv((void *) data_page))
 				goto out4;
 		}
 	}
 
-	retval = do_mount((char*)dev_page, dir_page, (char*)type_page,
+	retval = do_mount(kernel_dev, dir_page, kernel_type,
 			flags, (void*)data_page);
 
  out4:
 	free_page(data_page);
  out3:
-	free_page(dev_page);
+	kfree(kernel_dev);
  out2:
 	putname(dir_page);
  out1:
-	free_page(type_page);
+	kfree(kernel_type);
  out:
 	return retval;
 }
diff --git a/fs/dlm/lowcomms.c b/fs/dlm/lowcomms.c
index 240cef1..70736eb 100644
--- a/fs/dlm/lowcomms.c
+++ b/fs/dlm/lowcomms.c
@@ -316,6 +316,10 @@ int dlm_lowcomms_connect_node(int nodeid)
 {
 	struct connection *con;
 
+	/* with sctp there's no connecting without sending */
+	if (dlm_config.ci_protocol != 0)
+		return 0;
+
 	if (nodeid == dlm_our_nodeid())
 		return 0;
 
@@ -455,9 +459,9 @@ static void process_sctp_notification(struct connection *con,
 			int prim_len, ret;
 			int addr_len;
 			struct connection *new_con;
-			struct file *file;
 			sctp_peeloff_arg_t parg;
 			int parglen = sizeof(parg);
+			int err;
 
 			/*
 			 * We get this before any data for an association.
@@ -512,19 +516,22 @@ static void process_sctp_notification(struct connection *con,
 			ret = kernel_getsockopt(con->sock, IPPROTO_SCTP,
 						SCTP_SOCKOPT_PEELOFF,
 						(void *)&parg, &parglen);
-			if (ret) {
+			if (ret < 0) {
 				log_print("Can't peel off a socket for "
-					  "connection %d to node %d: err=%d\n",
+					  "connection %d to node %d: err=%d",
 					  parg.associd, nodeid, ret);
+				return;
+			}
+			new_con->sock = sockfd_lookup(parg.sd, &err);
+			if (!new_con->sock) {
+				log_print("sockfd_lookup error %d", err);
+				return;
 			}
-			file = fget(parg.sd);
-			new_con->sock = SOCKET_I(file->f_dentry->d_inode);
 			add_sock(new_con->sock, new_con);
-			fput(file);
-			put_unused_fd(parg.sd);
+			sockfd_put(new_con->sock);
 
-			log_print("got new/restarted association %d nodeid %d",
-				 (int)sn->sn_assoc_change.sac_assoc_id, nodeid);
+			log_print("connecting to %d sctp association %d",
+				 nodeid, (int)sn->sn_assoc_change.sac_assoc_id);
 
 			/* Send any pending writes */
 			clear_bit(CF_CONNECT_PENDING, &new_con->flags);
@@ -837,8 +844,6 @@ static void sctp_init_assoc(struct connection *con)
 	if (con->retries++ > MAX_CONNECT_RETRIES)
 		return;
 
-	log_print("Initiating association with node %d", con->nodeid);
-
 	if (nodeid_to_addr(con->nodeid, (struct sockaddr *)&rem_addr)) {
 		log_print("no address for nodeid %d", con->nodeid);
 		return;
@@ -855,11 +860,14 @@ static void sctp_init_assoc(struct connection *con)
 	outmessage.msg_flags = MSG_EOR;
 
 	spin_lock(&con->writequeue_lock);
-	e = list_entry(con->writequeue.next, struct writequeue_entry,
-		       list);
 
-	BUG_ON((struct list_head *) e == &con->writequeue);
+	if (list_empty(&con->writequeue)) {
+		spin_unlock(&con->writequeue_lock);
+		log_print("writequeue empty for nodeid %d", con->nodeid);
+		return;
+	}
 
+	e = list_first_entry(&con->writequeue, struct writequeue_entry, list);
 	len = e->len;
 	offset = e->offset;
 	spin_unlock(&con->writequeue_lock);
diff --git a/fs/drop_caches.c b/fs/drop_caches.c
index a2edb79..31f4b0e 100644
--- a/fs/drop_caches.c
+++ b/fs/drop_caches.c
@@ -63,9 +63,9 @@ static void drop_slab(void)
 }
 
 int drop_caches_sysctl_handler(ctl_table *table, int write,
-	struct file *file, void __user *buffer, size_t *length, loff_t *ppos)
+	void __user *buffer, size_t *length, loff_t *ppos)
 {
-	proc_dointvec_minmax(table, write, file, buffer, length, ppos);
+	proc_dointvec_minmax(table, write, buffer, length, ppos);
 	if (write) {
 		if (sysctl_drop_caches & 1)
 			drop_pagecache();
diff --git a/fs/ecryptfs/Kconfig b/fs/ecryptfs/Kconfig
index 0c754e6..1cd6d9d 100644
--- a/fs/ecryptfs/Kconfig
+++ b/fs/ecryptfs/Kconfig
@@ -1,6 +1,9 @@
 config ECRYPT_FS
 	tristate "eCrypt filesystem layer support (EXPERIMENTAL)"
-	depends on EXPERIMENTAL && KEYS && CRYPTO && NET
+	depends on EXPERIMENTAL && KEYS && CRYPTO
+	select CRYPTO_ECB
+	select CRYPTO_CBC
+	select CRYPTO_MD5
 	help
 	  Encrypted filesystem that operates on the VFS layer.  See
 	  <file:Documentation/filesystems/ecryptfs.txt> to learn more about
diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c
index b91851f..fbb6e5e 100644
--- a/fs/ecryptfs/crypto.c
+++ b/fs/ecryptfs/crypto.c
@@ -245,13 +245,11 @@ void ecryptfs_destroy_crypt_stat(struct ecryptfs_crypt_stat *crypt_stat)
 		crypto_free_blkcipher(crypt_stat->tfm);
 	if (crypt_stat->hash_tfm)
 		crypto_free_hash(crypt_stat->hash_tfm);
-	mutex_lock(&crypt_stat->keysig_list_mutex);
 	list_for_each_entry_safe(key_sig, key_sig_tmp,
 				 &crypt_stat->keysig_list, crypt_stat_list) {
 		list_del(&key_sig->crypt_stat_list);
 		kmem_cache_free(ecryptfs_key_sig_cache, key_sig);
 	}
-	mutex_unlock(&crypt_stat->keysig_list_mutex);
 	memset(crypt_stat, 0, sizeof(struct ecryptfs_crypt_stat));
 }
 
@@ -511,13 +509,14 @@ int ecryptfs_encrypt_page(struct page *page)
 				  + extent_offset), crypt_stat);
 		rc = ecryptfs_write_lower(ecryptfs_inode, enc_extent_virt,
 					  offset, crypt_stat->extent_size);
-		if (rc) {
+		if (rc < 0) {
 			ecryptfs_printk(KERN_ERR, "Error attempting "
 					"to write lower page; rc = [%d]"
 					"\n", rc);
 			goto out;
 		}
 	}
+	rc = 0;
 out:
 	if (enc_extent_page) {
 		kunmap(enc_extent_page);
@@ -633,7 +632,7 @@ int ecryptfs_decrypt_page(struct page *page)
 		rc = ecryptfs_read_lower(enc_extent_virt, offset,
 					 crypt_stat->extent_size,
 					 ecryptfs_inode);
-		if (rc) {
+		if (rc < 0) {
 			ecryptfs_printk(KERN_ERR, "Error attempting "
 					"to read lower page; rc = [%d]"
 					"\n", rc);
@@ -797,6 +796,7 @@ int ecryptfs_init_crypt_ctx(struct ecryptfs_crypt_stat *crypt_stat)
 	kfree(full_alg_name);
 	if (IS_ERR(crypt_stat->tfm)) {
 		rc = PTR_ERR(crypt_stat->tfm);
+		crypt_stat->tfm = NULL;
 		ecryptfs_printk(KERN_ERR, "cryptfs: init_crypt_ctx(): "
 				"Error initializing cipher [%s]\n",
 				crypt_stat->cipher);
@@ -925,7 +925,9 @@ static int ecryptfs_copy_mount_wide_sigs_to_inode_sigs(
 	struct ecryptfs_global_auth_tok *global_auth_tok;
 	int rc = 0;
 
+	mutex_lock(&crypt_stat->keysig_list_mutex);
 	mutex_lock(&mount_crypt_stat->global_auth_tok_list_mutex);
+
 	list_for_each_entry(global_auth_tok,
 			    &mount_crypt_stat->global_auth_tok_list,
 			    mount_crypt_stat_list) {
@@ -934,13 +936,13 @@ static int ecryptfs_copy_mount_wide_sigs_to_inode_sigs(
 		rc = ecryptfs_add_keysig(crypt_stat, global_auth_tok->sig);
 		if (rc) {
 			printk(KERN_ERR "Error adding keysig; rc = [%d]\n", rc);
-			mutex_unlock(
-				&mount_crypt_stat->global_auth_tok_list_mutex);
 			goto out;
 		}
 	}
-	mutex_unlock(&mount_crypt_stat->global_auth_tok_list_mutex);
+
 out:
+	mutex_unlock(&mount_crypt_stat->global_auth_tok_list_mutex);
+	mutex_unlock(&crypt_stat->keysig_list_mutex);
 	return rc;
 }
 
@@ -1212,14 +1214,15 @@ int ecryptfs_read_and_validate_header_region(char *data,
 		crypt_stat->extent_size = ECRYPTFS_DEFAULT_EXTENT_SIZE;
 	rc = ecryptfs_read_lower(data, 0, crypt_stat->extent_size,
 				 ecryptfs_inode);
-	if (rc) {
+	if (rc < 0) {
 		printk(KERN_ERR "%s: Error reading header region; rc = [%d]\n",
 		       __func__, rc);
 		goto out;
 	}
 	if (!contains_ecryptfs_marker(data + ECRYPTFS_FILE_SIZE_BYTES)) {
 		rc = -EINVAL;
-	}
+	} else
+		rc = 0;
 out:
 	return rc;
 }
@@ -1314,10 +1317,11 @@ ecryptfs_write_metadata_to_contents(struct dentry *ecryptfs_dentry,
 
 	rc = ecryptfs_write_lower(ecryptfs_dentry->d_inode, virt,
 				  0, virt_len);
-	if (rc)
+	if (rc < 0)
 		printk(KERN_ERR "%s: Error attempting to write header "
-		       "information to lower file; rc = [%d]\n", __func__,
-		       rc);
+		       "information to lower file; rc = [%d]\n", __func__, rc);
+	else
+		rc = 0;
 	return rc;
 }
 
@@ -1597,7 +1601,7 @@ int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry)
 	}
 	rc = ecryptfs_read_lower(page_virt, 0, crypt_stat->extent_size,
 				 ecryptfs_inode);
-	if (!rc)
+	if (rc >= 0)
 		rc = ecryptfs_read_headers_virt(page_virt, crypt_stat,
 						ecryptfs_dentry,
 						ECRYPTFS_VALIDATE_HEADER_SIZE);
@@ -1702,7 +1706,7 @@ ecryptfs_encrypt_filename(struct ecryptfs_filename *filename,
 	} else {
 		printk(KERN_ERR "%s: No support for requested filename "
 		       "encryption method in this release\n", __func__);
-		rc = -ENOTSUPP;
+		rc = -EOPNOTSUPP;
 		goto out;
 	}
 out:
@@ -1763,7 +1767,7 @@ ecryptfs_process_key_cipher(struct crypto_blkcipher **key_tfm,
 	if (IS_ERR(*key_tfm)) {
 		rc = PTR_ERR(*key_tfm);
 		printk(KERN_ERR "Unable to allocate crypto cipher with name "
-		       "[%s]; rc = [%d]\n", cipher_name, rc);
+		       "[%s]; rc = [%d]\n", full_alg_name, rc);
 		goto out;
 	}
 	crypto_blkcipher_set_flags(*key_tfm, CRYPTO_TFM_REQ_WEAK_KEY);
@@ -1776,7 +1780,8 @@ ecryptfs_process_key_cipher(struct crypto_blkcipher **key_tfm,
 	rc = crypto_blkcipher_setkey(*key_tfm, dummy_key, *key_size);
 	if (rc) {
 		printk(KERN_ERR "Error attempting to set key of size [%zd] for "
-		       "cipher [%s]; rc = [%d]\n", *key_size, cipher_name, rc);
+		       "cipher [%s]; rc = [%d]\n", *key_size, full_alg_name,
+		       rc);
 		rc = -EINVAL;
 		goto out;
 	}
@@ -2166,7 +2171,7 @@ int ecryptfs_encrypt_and_encode_filename(
 			(*encoded_name)[(*encoded_name_size)] = '\0';
 			(*encoded_name_size)++;
 		} else {
-			rc = -ENOTSUPP;
+			rc = -EOPNOTSUPP;
 		}
 		if (rc) {
 			printk(KERN_ERR "%s: Error attempting to encode "
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index 2f0945d..056fed62 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -476,6 +476,7 @@ static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry)
 	struct inode *lower_dir_inode = ecryptfs_inode_to_lower(dir);
 	struct dentry *lower_dir_dentry;
 
+	dget(lower_dentry);
 	lower_dir_dentry = lock_parent(lower_dentry);
 	rc = vfs_unlink(lower_dir_inode, lower_dentry);
 	if (rc) {
@@ -489,6 +490,7 @@ static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry)
 	d_drop(dentry);
 out_unlock:
 	unlock_dir(lower_dir_dentry);
+	dput(lower_dentry);
 	return rc;
 }
 
diff --git a/fs/ecryptfs/keystore.c b/fs/ecryptfs/keystore.c
index 259525c9..a0a7847 100644
--- a/fs/ecryptfs/keystore.c
+++ b/fs/ecryptfs/keystore.c
@@ -416,7 +416,9 @@ ecryptfs_find_global_auth_tok_for_sig(
 			    &mount_crypt_stat->global_auth_tok_list,
 			    mount_crypt_stat_list) {
 		if (memcmp(walker->sig, sig, ECRYPTFS_SIG_SIZE_HEX) == 0) {
-			(*global_auth_tok) = walker;
+			rc = key_validate(walker->global_auth_tok_key);
+			if (!rc)
+				(*global_auth_tok) = walker;
 			goto out;
 		}
 	}
@@ -612,7 +614,12 @@ ecryptfs_write_tag_70_packet(char *dest, size_t *remaining_bytes,
 	}
 	/* TODO: Support other key modules than passphrase for
 	 * filename encryption */
-	BUG_ON(s->auth_tok->token_type != ECRYPTFS_PASSWORD);
+	if (s->auth_tok->token_type != ECRYPTFS_PASSWORD) {
+		rc = -EOPNOTSUPP;
+		printk(KERN_INFO "%s: Filename encryption only supports "
+		       "password tokens\n", __func__);
+		goto out_free_unlock;
+	}
 	sg_init_one(
 		&s->hash_sg,
 		(u8 *)s->auth_tok->token.password.session_key_encryption_key,
@@ -910,7 +917,12 @@ ecryptfs_parse_tag_70_packet(char **filename, size_t *filename_size,
 	}
 	/* TODO: Support other key modules than passphrase for
 	 * filename encryption */
-	BUG_ON(s->auth_tok->token_type != ECRYPTFS_PASSWORD);
+	if (s->auth_tok->token_type != ECRYPTFS_PASSWORD) {
+		rc = -EOPNOTSUPP;
+		printk(KERN_INFO "%s: Filename encryption only supports "
+		       "password tokens\n", __func__);
+		goto out_free_unlock;
+	}
 	rc = crypto_blkcipher_setkey(
 		s->desc.tfm,
 		s->auth_tok->token.password.session_key_encryption_key,
@@ -1316,8 +1328,10 @@ parse_tag_3_packet(struct ecryptfs_crypt_stat *crypt_stat,
 		rc = -EINVAL;
 		goto out_free;
 	}
-	ecryptfs_cipher_code_to_string(crypt_stat->cipher,
-				       (u16)data[(*packet_size)]);
+	rc = ecryptfs_cipher_code_to_string(crypt_stat->cipher,
+					    (u16)data[(*packet_size)]);
+	if (rc)
+		goto out_free;
 	/* A little extra work to differentiate among the AES key
 	 * sizes; see RFC2440 */
 	switch(data[(*packet_size)++]) {
@@ -1328,7 +1342,9 @@ parse_tag_3_packet(struct ecryptfs_crypt_stat *crypt_stat,
 		crypt_stat->key_size =
 			(*new_auth_tok)->session_key.encrypted_key_size;
 	}
-	ecryptfs_init_crypt_ctx(crypt_stat);
+	rc = ecryptfs_init_crypt_ctx(crypt_stat);
+	if (rc)
+		goto out_free;
 	if (unlikely(data[(*packet_size)++] != 0x03)) {
 		printk(KERN_WARNING "Only S2K ID 3 is currently supported\n");
 		rc = -ENOSYS;
@@ -2366,21 +2382,18 @@ struct kmem_cache *ecryptfs_key_sig_cache;
 int ecryptfs_add_keysig(struct ecryptfs_crypt_stat *crypt_stat, char *sig)
 {
 	struct ecryptfs_key_sig *new_key_sig;
-	int rc = 0;
 
 	new_key_sig = kmem_cache_alloc(ecryptfs_key_sig_cache, GFP_KERNEL);
 	if (!new_key_sig) {
-		rc = -ENOMEM;
 		printk(KERN_ERR
 		       "Error allocating from ecryptfs_key_sig_cache\n");
-		goto out;
+		return -ENOMEM;
 	}
 	memcpy(new_key_sig->keysig, sig, ECRYPTFS_SIG_SIZE_HEX);
-	mutex_lock(&crypt_stat->keysig_list_mutex);
+	/* Caller must hold keysig_list_mutex */
 	list_add(&new_key_sig->crypt_stat_list, &crypt_stat->keysig_list);
-	mutex_unlock(&crypt_stat->keysig_list_mutex);
-out:
-	return rc;
+
+	return 0;
 }
 
 struct kmem_cache *ecryptfs_global_auth_tok_cache;
diff --git a/fs/ecryptfs/kthread.c b/fs/ecryptfs/kthread.c
index c6d7a4d..e14cf7e 100644
--- a/fs/ecryptfs/kthread.c
+++ b/fs/ecryptfs/kthread.c
@@ -136,6 +136,7 @@ int ecryptfs_privileged_open(struct file **lower_file,
 			     const struct cred *cred)
 {
 	struct ecryptfs_open_req *req;
+	int flags = O_LARGEFILE;
 	int rc = 0;
 
 	/* Corresponding dput() and mntput() are done when the
@@ -143,10 +144,14 @@ int ecryptfs_privileged_open(struct file **lower_file,
 	 * destroyed. */
 	dget(lower_dentry);
 	mntget(lower_mnt);
-	(*lower_file) = dentry_open(lower_dentry, lower_mnt,
-				    (O_RDWR | O_LARGEFILE), cred);
+	flags |= IS_RDONLY(lower_dentry->d_inode) ? O_RDONLY : O_RDWR;
+	(*lower_file) = dentry_open(lower_dentry, lower_mnt, flags, cred);
 	if (!IS_ERR(*lower_file))
 		goto out;
+	if (flags & O_RDONLY) {
+		rc = PTR_ERR((*lower_file));
+		goto out;
+	}
 	req = kmem_cache_alloc(ecryptfs_open_req_cache, GFP_KERNEL);
 	if (!req) {
 		rc = -ENOMEM;
@@ -180,21 +185,8 @@ int ecryptfs_privileged_open(struct file **lower_file,
 		       __func__);
 		goto out_unlock;
 	}
-	if (IS_ERR(*req->lower_file)) {
+	if (IS_ERR(*req->lower_file))
 		rc = PTR_ERR(*req->lower_file);
-		dget(lower_dentry);
-		mntget(lower_mnt);
-		(*lower_file) = dentry_open(lower_dentry, lower_mnt,
-					    (O_RDONLY | O_LARGEFILE), cred);
-		if (IS_ERR(*lower_file)) {
-			rc = PTR_ERR(*req->lower_file);
-			(*lower_file) = NULL;
-			printk(KERN_WARNING "%s: Error attempting privileged "
-			       "open of lower file with either RW or RO "
-			       "perms; rc = [%d]. Giving up.\n",
-			       __func__, rc);
-		}
-	}
 out_unlock:
 	mutex_unlock(&req->mux);
 out_free:
diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c
index 9f0aa98..c6ac85d 100644
--- a/fs/ecryptfs/main.c
+++ b/fs/ecryptfs/main.c
@@ -35,6 +35,7 @@
 #include <linux/key.h>
 #include <linux/parser.h>
 #include <linux/fs_stack.h>
+#include <linux/ima.h>
 #include "ecryptfs_kernel.h"
 
 /**
@@ -118,6 +119,7 @@ int ecryptfs_init_persistent_file(struct dentry *ecryptfs_dentry)
 	const struct cred *cred = current_cred();
 	struct ecryptfs_inode_info *inode_info =
 		ecryptfs_inode_to_private(ecryptfs_dentry->d_inode);
+	int opened_lower_file = 0;
 	int rc = 0;
 
 	mutex_lock(&inode_info->lower_file_mutex);
@@ -129,15 +131,17 @@ int ecryptfs_init_persistent_file(struct dentry *ecryptfs_dentry)
 		lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
 		rc = ecryptfs_privileged_open(&inode_info->lower_file,
 					      lower_dentry, lower_mnt, cred);
-		if (rc || IS_ERR(inode_info->lower_file)) {
+		if (rc) {
 			printk(KERN_ERR "Error opening lower persistent file "
 			       "for lower_dentry [0x%p] and lower_mnt [0x%p]; "
 			       "rc = [%d]\n", lower_dentry, lower_mnt, rc);
-			rc = PTR_ERR(inode_info->lower_file);
 			inode_info->lower_file = NULL;
-		}
+		} else
+			opened_lower_file = 1;
 	}
 	mutex_unlock(&inode_info->lower_file_mutex);
+	if (opened_lower_file)
+		ima_counts_get(inode_info->lower_file);
 	return rc;
 }
 
diff --git a/fs/ecryptfs/mmap.c b/fs/ecryptfs/mmap.c
index 05772ae..df4ce99d 100644
--- a/fs/ecryptfs/mmap.c
+++ b/fs/ecryptfs/mmap.c
@@ -396,9 +396,11 @@ static int ecryptfs_write_inode_size_to_header(struct inode *ecryptfs_inode)
 	rc = ecryptfs_write_lower(ecryptfs_inode, file_size_virt, 0,
 				  sizeof(u64));
 	kfree(file_size_virt);
-	if (rc)
+	if (rc < 0)
 		printk(KERN_ERR "%s: Error writing file size to header; "
 		       "rc = [%d]\n", __func__, rc);
+	else
+		rc = 0;
 out:
 	return rc;
 }
diff --git a/fs/ecryptfs/read_write.c b/fs/ecryptfs/read_write.c
index a137c6e..0cc4faf 100644
--- a/fs/ecryptfs/read_write.c
+++ b/fs/ecryptfs/read_write.c
@@ -34,15 +34,14 @@
  *
  * Write data to the lower file.
  *
- * Returns zero on success; non-zero on error
+ * Returns bytes written on success; less than zero on error
  */
 int ecryptfs_write_lower(struct inode *ecryptfs_inode, char *data,
 			 loff_t offset, size_t size)
 {
 	struct ecryptfs_inode_info *inode_info;
-	ssize_t octets_written;
 	mm_segment_t fs_save;
-	int rc = 0;
+	ssize_t rc;
 
 	inode_info = ecryptfs_inode_to_private(ecryptfs_inode);
 	mutex_lock(&inode_info->lower_file_mutex);
@@ -50,14 +49,9 @@ int ecryptfs_write_lower(struct inode *ecryptfs_inode, char *data,
 	inode_info->lower_file->f_pos = offset;
 	fs_save = get_fs();
 	set_fs(get_ds());
-	octets_written = vfs_write(inode_info->lower_file, data, size,
-				   &inode_info->lower_file->f_pos);
+	rc = vfs_write(inode_info->lower_file, data, size,
+		       &inode_info->lower_file->f_pos);
 	set_fs(fs_save);
-	if (octets_written < 0) {
-		printk(KERN_ERR "%s: octets_written = [%td]; "
-		       "expected [%td]\n", __func__, octets_written, size);
-		rc = -EINVAL;
-	}
 	mutex_unlock(&inode_info->lower_file_mutex);
 	mark_inode_dirty_sync(ecryptfs_inode);
 	return rc;
@@ -91,6 +85,8 @@ int ecryptfs_write_lower_page_segment(struct inode *ecryptfs_inode,
 		  + offset_in_page);
 	virt = kmap(page_for_lower);
 	rc = ecryptfs_write_lower(ecryptfs_inode, virt, offset, size);
+	if (rc > 0)
+		rc = 0;
 	kunmap(page_for_lower);
 	return rc;
 }
@@ -229,30 +225,24 @@ out:
  * Read @size bytes of data at byte offset @offset from the lower
  * inode into memory location @data.
  *
- * Returns zero on success; non-zero on error
+ * Returns bytes read on success; 0 on EOF; less than zero on error
  */
 int ecryptfs_read_lower(char *data, loff_t offset, size_t size,
 			struct inode *ecryptfs_inode)
 {
 	struct ecryptfs_inode_info *inode_info =
 		ecryptfs_inode_to_private(ecryptfs_inode);
-	ssize_t octets_read;
 	mm_segment_t fs_save;
-	int rc = 0;
+	ssize_t rc;
 
 	mutex_lock(&inode_info->lower_file_mutex);
 	BUG_ON(!inode_info->lower_file);
 	inode_info->lower_file->f_pos = offset;
 	fs_save = get_fs();
 	set_fs(get_ds());
-	octets_read = vfs_read(inode_info->lower_file, data, size,
-			       &inode_info->lower_file->f_pos);
+	rc = vfs_read(inode_info->lower_file, data, size,
+		      &inode_info->lower_file->f_pos);
 	set_fs(fs_save);
-	if (octets_read < 0) {
-		printk(KERN_ERR "%s: octets_read = [%td]; "
-		       "expected [%td]\n", __func__, octets_read, size);
-		rc = -EINVAL;
-	}
 	mutex_unlock(&inode_info->lower_file_mutex);
 	return rc;
 }
@@ -284,6 +274,8 @@ int ecryptfs_read_lower_page_segment(struct page *page_for_ecryptfs,
 	offset = ((((loff_t)page_index) << PAGE_CACHE_SHIFT) + offset_in_page);
 	virt = kmap(page_for_ecryptfs);
 	rc = ecryptfs_read_lower(virt, offset, size, ecryptfs_inode);
+	if (rc > 0)
+		rc = 0;
 	kunmap(page_for_ecryptfs);
 	flush_dcache_page(page_for_ecryptfs);
 	return rc;
diff --git a/fs/ecryptfs/super.c b/fs/ecryptfs/super.c
index 12d6496..b15a43a 100644
--- a/fs/ecryptfs/super.c
+++ b/fs/ecryptfs/super.c
@@ -77,7 +77,6 @@ static void ecryptfs_destroy_inode(struct inode *inode)
 	struct ecryptfs_inode_info *inode_info;
 
 	inode_info = ecryptfs_inode_to_private(inode);
-	mutex_lock(&inode_info->lower_file_mutex);
 	if (inode_info->lower_file) {
 		struct dentry *lower_dentry =
 			inode_info->lower_file->f_dentry;
@@ -89,7 +88,6 @@ static void ecryptfs_destroy_inode(struct inode *inode)
 			d_drop(lower_dentry);
 		}
 	}
-	mutex_unlock(&inode_info->lower_file_mutex);
 	ecryptfs_destroy_crypt_stat(&inode_info->crypt_stat);
 	kmem_cache_free(ecryptfs_inode_info_cache, inode_info);
 }
diff --git a/fs/exec.c b/fs/exec.c
index 5c833c1..d49be6b 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -55,6 +55,7 @@
 #include <linux/kmod.h>
 #include <linux/fsnotify.h>
 #include <linux/fs_struct.h>
+#include <linux/pipe_fs_i.h>
 
 #include <asm/uaccess.h>
 #include <asm/mmu_context.h>
@@ -63,6 +64,7 @@
 
 int core_uses_pid;
 char core_pattern[CORENAME_MAX_SIZE] = "core";
+unsigned int core_pipe_limit;
 int suid_dumpable = 0;
 
 /* The maximal length of core_pattern is also specified in sysctl.c */
@@ -1393,18 +1395,16 @@ out_ret:
 	return retval;
 }
 
-int set_binfmt(struct linux_binfmt *new)
+void set_binfmt(struct linux_binfmt *new)
 {
-	struct linux_binfmt *old = current->binfmt;
+	struct mm_struct *mm = current->mm;
 
-	if (new) {
-		if (!try_module_get(new->module))
-			return -1;
-	}
-	current->binfmt = new;
-	if (old)
-		module_put(old->module);
-	return 0;
+	if (mm->binfmt)
+		module_put(mm->binfmt->module);
+
+	mm->binfmt = new;
+	if (new)
+		__module_get(new->module);
 }
 
 EXPORT_SYMBOL(set_binfmt);
@@ -1728,6 +1728,29 @@ int get_dumpable(struct mm_struct *mm)
 	return (ret >= 2) ? 2 : ret;
 }
 
+static void wait_for_dump_helpers(struct file *file)
+{
+	struct pipe_inode_info *pipe;
+
+	pipe = file->f_path.dentry->d_inode->i_pipe;
+
+	pipe_lock(pipe);
+	pipe->readers++;
+	pipe->writers--;
+
+	while ((pipe->readers > 1) && (!signal_pending(current))) {
+		wake_up_interruptible_sync(&pipe->wait);
+		kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
+		pipe_wait(pipe);
+	}
+
+	pipe->readers--;
+	pipe->writers++;
+	pipe_unlock(pipe);
+
+}
+
+
 void do_coredump(long signr, int exit_code, struct pt_regs *regs)
 {
 	struct core_state core_state;
@@ -1744,11 +1767,12 @@ void do_coredump(long signr, int exit_code, struct pt_regs *regs)
 	unsigned long core_limit = current->signal->rlim[RLIMIT_CORE].rlim_cur;
 	char **helper_argv = NULL;
 	int helper_argc = 0;
-	char *delimit;
+	int dump_count = 0;
+	static atomic_t core_dump_count = ATOMIC_INIT(0);
 
 	audit_core_dumps(signr);
 
-	binfmt = current->binfmt;
+	binfmt = mm->binfmt;
 	if (!binfmt || !binfmt->core_dump)
 		goto fail;
 
@@ -1799,54 +1823,63 @@ void do_coredump(long signr, int exit_code, struct pt_regs *regs)
  	lock_kernel();
 	ispipe = format_corename(corename, signr);
 	unlock_kernel();
-	/*
-	 * Don't bother to check the RLIMIT_CORE value if core_pattern points
-	 * to a pipe.  Since we're not writing directly to the filesystem
-	 * RLIMIT_CORE doesn't really apply, as no actual core file will be
-	 * created unless the pipe reader choses to write out the core file
-	 * at which point file size limits and permissions will be imposed
-	 * as it does with any other process
-	 */
+
 	if ((!ispipe) && (core_limit < binfmt->min_coredump))
 		goto fail_unlock;
 
  	if (ispipe) {
+		if (core_limit == 0) {
+			/*
+			 * Normally core limits are irrelevant to pipes, since
+			 * we're not writing to the file system, but we use
+			 * core_limit of 0 here as a speacial value. Any
+			 * non-zero limit gets set to RLIM_INFINITY below, but
+			 * a limit of 0 skips the dump.  This is a consistent
+			 * way to catch recursive crashes.  We can still crash
+			 * if the core_pattern binary sets RLIM_CORE =  !0
+			 * but it runs as root, and can do lots of stupid things
+			 * Note that we use task_tgid_vnr here to grab the pid
+			 * of the process group leader.  That way we get the
+			 * right pid if a thread in a multi-threaded
+			 * core_pattern process dies.
+			 */
+			printk(KERN_WARNING
+				"Process %d(%s) has RLIMIT_CORE set to 0\n",
+				task_tgid_vnr(current), current->comm);
+			printk(KERN_WARNING "Aborting core\n");
+			goto fail_unlock;
+		}
+
+		dump_count = atomic_inc_return(&core_dump_count);
+		if (core_pipe_limit && (core_pipe_limit < dump_count)) {
+			printk(KERN_WARNING "Pid %d(%s) over core_pipe_limit\n",
+			       task_tgid_vnr(current), current->comm);
+			printk(KERN_WARNING "Skipping core dump\n");
+			goto fail_dropcount;
+		}
+
 		helper_argv = argv_split(GFP_KERNEL, corename+1, &helper_argc);
 		if (!helper_argv) {
 			printk(KERN_WARNING "%s failed to allocate memory\n",
 			       __func__);
-			goto fail_unlock;
-		}
-		/* Terminate the string before the first option */
-		delimit = strchr(corename, ' ');
-		if (delimit)
-			*delimit = '\0';
-		delimit = strrchr(helper_argv[0], '/');
-		if (delimit)
-			delimit++;
-		else
-			delimit = helper_argv[0];
-		if (!strcmp(delimit, current->comm)) {
-			printk(KERN_NOTICE "Recursive core dump detected, "
-					"aborting\n");
-			goto fail_unlock;
+			goto fail_dropcount;
 		}
 
 		core_limit = RLIM_INFINITY;
 
 		/* SIGPIPE can happen, but it's just never processed */
- 		if (call_usermodehelper_pipe(corename+1, helper_argv, NULL,
+		if (call_usermodehelper_pipe(helper_argv[0], helper_argv, NULL,
 				&file)) {
  			printk(KERN_INFO "Core dump to %s pipe failed\n",
 			       corename);
- 			goto fail_unlock;
+			goto fail_dropcount;
  		}
  	} else
  		file = filp_open(corename,
 				 O_CREAT | 2 | O_NOFOLLOW | O_LARGEFILE | flag,
 				 0600);
 	if (IS_ERR(file))
-		goto fail_unlock;
+		goto fail_dropcount;
 	inode = file->f_path.dentry->d_inode;
 	if (inode->i_nlink > 1)
 		goto close_fail;	/* multiple links - don't dump */
@@ -1875,7 +1908,12 @@ void do_coredump(long signr, int exit_code, struct pt_regs *regs)
 	if (retval)
 		current->signal->group_exit_code |= 0x80;
 close_fail:
+	if (ispipe && core_pipe_limit)
+		wait_for_dump_helpers(file);
 	filp_close(file, NULL);
+fail_dropcount:
+	if (dump_count)
+		atomic_dec(&core_dump_count);
 fail_unlock:
 	if (helper_argv)
 		argv_free(helper_argv);
diff --git a/fs/exofs/super.c b/fs/exofs/super.c
index 5ab10c3..9f500de 100644
--- a/fs/exofs/super.c
+++ b/fs/exofs/super.c
@@ -214,7 +214,6 @@ int exofs_sync_fs(struct super_block *sb, int wait)
 	}
 
 	lock_super(sb);
-	lock_kernel();
 	sbi = sb->s_fs_info;
 	fscb->s_nextid = cpu_to_le64(sbi->s_nextid);
 	fscb->s_numfiles = cpu_to_le32(sbi->s_numfiles);
@@ -245,7 +244,6 @@ int exofs_sync_fs(struct super_block *sb, int wait)
 out:
 	if (or)
 		osd_end_request(or);
-	unlock_kernel();
 	unlock_super(sb);
 	kfree(fscb);
 	return ret;
@@ -268,8 +266,6 @@ static void exofs_put_super(struct super_block *sb)
 	int num_pend;
 	struct exofs_sb_info *sbi = sb->s_fs_info;
 
-	lock_kernel();
-
 	if (sb->s_dirt)
 		exofs_write_super(sb);
 
@@ -286,8 +282,6 @@ static void exofs_put_super(struct super_block *sb)
 	osduld_put_device(sbi->s_dev);
 	kfree(sb->s_fs_info);
 	sb->s_fs_info = NULL;
-
-	unlock_kernel();
 }
 
 /*
diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
index 1c1638f..ade6340 100644
--- a/fs/ext2/inode.c
+++ b/fs/ext2/inode.c
@@ -819,6 +819,7 @@ const struct address_space_operations ext2_aops = {
 	.writepages		= ext2_writepages,
 	.migratepage		= buffer_migrate_page,
 	.is_partially_uptodate	= block_is_partially_uptodate,
+	.error_remove_page	= generic_error_remove_page,
 };
 
 const struct address_space_operations ext2_aops_xip = {
@@ -837,6 +838,7 @@ const struct address_space_operations ext2_nobh_aops = {
 	.direct_IO		= ext2_direct_IO,
 	.writepages		= ext2_writepages,
 	.migratepage		= buffer_migrate_page,
+	.error_remove_page	= generic_error_remove_page,
 };
 
 /*
diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c
index cd098a7..acf1b14 100644
--- a/fs/ext3/inode.c
+++ b/fs/ext3/inode.c
@@ -1830,6 +1830,7 @@ static const struct address_space_operations ext3_ordered_aops = {
 	.direct_IO		= ext3_direct_IO,
 	.migratepage		= buffer_migrate_page,
 	.is_partially_uptodate  = block_is_partially_uptodate,
+	.error_remove_page	= generic_error_remove_page,
 };
 
 static const struct address_space_operations ext3_writeback_aops = {
@@ -1845,6 +1846,7 @@ static const struct address_space_operations ext3_writeback_aops = {
 	.direct_IO		= ext3_direct_IO,
 	.migratepage		= buffer_migrate_page,
 	.is_partially_uptodate  = block_is_partially_uptodate,
+	.error_remove_page	= generic_error_remove_page,
 };
 
 static const struct address_space_operations ext3_journalled_aops = {
@@ -1859,6 +1861,7 @@ static const struct address_space_operations ext3_journalled_aops = {
 	.invalidatepage		= ext3_invalidatepage,
 	.releasepage		= ext3_releasepage,
 	.is_partially_uptodate  = block_is_partially_uptodate,
+	.error_remove_page	= generic_error_remove_page,
 };
 
 void ext3_set_aops(struct inode *inode)
diff --git a/fs/ext3/super.c b/fs/ext3/super.c
index 72743d3..7a520a8 100644
--- a/fs/ext3/super.c
+++ b/fs/ext3/super.c
@@ -2321,7 +2321,18 @@ static int ext3_commit_super(struct super_block *sb,
 
 	if (!sbh)
 		return error;
-	es->s_wtime = cpu_to_le32(get_seconds());
+	/*
+	 * If the file system is mounted read-only, don't update the
+	 * superblock write time.  This avoids updating the superblock
+	 * write time when we are mounting the root file system
+	 * read/only but we need to replay the journal; at that point,
+	 * for people who are east of GMT and who make their clock
+	 * tick in localtime for Windows bug-for-bug compatibility,
+	 * the clock is set in the future, and this will cause e2fsck
+	 * to complain and force a full file system check.
+	 */
+	if (!(sb->s_flags & MS_RDONLY))
+		es->s_wtime = cpu_to_le32(get_seconds());
 	es->s_free_blocks_count = cpu_to_le32(ext3_count_free_blocks(sb));
 	es->s_free_inodes_count = cpu_to_le32(ext3_count_free_inodes(sb));
 	BUFFER_TRACE(sbh, "marking dirty");
diff --git a/fs/ext4/Kconfig b/fs/ext4/Kconfig
index d5c0ea2..9f2d45d 100644
--- a/fs/ext4/Kconfig
+++ b/fs/ext4/Kconfig
@@ -26,20 +26,6 @@ config EXT4_FS
 
 	  If unsure, say N.
 
-config EXT4DEV_COMPAT
-	bool "Enable ext4dev compatibility"
-	depends on EXT4_FS
-	help
-	  Starting with 2.6.28, the name of the ext4 filesystem was
-	  renamed from ext4dev to ext4.  Unfortunately there are some
-	  legacy userspace programs (such as klibc's fstype) have
-	  "ext4dev" hardcoded.
-
-	  To enable backwards compatibility so that systems that are
-	  still expecting to mount ext4 filesystems using ext4dev,
-	  choose Y here.   This feature will go away by 2.6.31, so
-	  please arrange to get your userspace programs fixed!
-
 config EXT4_FS_XATTR
 	bool "Ext4 extended attributes"
 	depends on EXT4_FS
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index e227eea..984ca0c 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -65,6 +65,12 @@ typedef __u32 ext4_lblk_t;
 /* data type for block group number */
 typedef unsigned int ext4_group_t;
 
+/*
+ * Flags used in mballoc's allocation_context flags field.  
+ *
+ * Also used to show what's going on for debugging purposes when the
+ * flag field is exported via the traceport interface
+ */
 
 /* prefer goal again. length */
 #define EXT4_MB_HINT_MERGE		0x0001
@@ -127,6 +133,16 @@ struct mpage_da_data {
 	int pages_written;
 	int retval;
 };
+#define	DIO_AIO_UNWRITTEN	0x1
+typedef struct ext4_io_end {
+	struct list_head	list;		/* per-file finished AIO list */
+	struct inode		*inode;		/* file being written to */
+	unsigned int		flag;		/* unwritten or not */
+	int			error;		/* I/O error code */
+	ext4_lblk_t		offset;		/* offset in the file */
+	size_t			size;		/* size of the extent */
+	struct work_struct	work;		/* data work queue */
+} ext4_io_end_t;
 
 /*
  * Special inodes numbers
@@ -347,7 +363,16 @@ struct ext4_new_group_data {
 	/* Call ext4_da_update_reserve_space() after successfully 
 	   allocating the blocks */
 #define EXT4_GET_BLOCKS_UPDATE_RESERVE_SPACE	0x0008
-
+	/* caller is from the direct IO path, request to creation of an
+	unitialized extents if not allocated, split the uninitialized
+	extent if blocks has been preallocated already*/
+#define EXT4_GET_BLOCKS_DIO			0x0010
+#define EXT4_GET_BLOCKS_CONVERT			0x0020
+#define EXT4_GET_BLOCKS_DIO_CREATE_EXT		(EXT4_GET_BLOCKS_DIO|\
+					 EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
+	/* Convert extent to initialized after direct IO complete */
+#define EXT4_GET_BLOCKS_DIO_CONVERT_EXT		(EXT4_GET_BLOCKS_CONVERT|\
+					 EXT4_GET_BLOCKS_DIO_CREATE_EXT)
 
 /*
  * ioctl commands
@@ -500,8 +525,8 @@ struct move_extent {
 static inline __le32 ext4_encode_extra_time(struct timespec *time)
 {
        return cpu_to_le32((sizeof(time->tv_sec) > 4 ?
-			   time->tv_sec >> 32 : 0) |
-			   ((time->tv_nsec << 2) & EXT4_NSEC_MASK));
+			   (time->tv_sec >> 32) & EXT4_EPOCH_MASK : 0) |
+                          ((time->tv_nsec << EXT4_EPOCH_BITS) & EXT4_NSEC_MASK));
 }
 
 static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
@@ -509,7 +534,7 @@ static inline void ext4_decode_extra_time(struct timespec *time, __le32 extra)
        if (sizeof(time->tv_sec) > 4)
 	       time->tv_sec |= (__u64)(le32_to_cpu(extra) & EXT4_EPOCH_MASK)
 			       << 32;
-       time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> 2;
+       time->tv_nsec = (le32_to_cpu(extra) & EXT4_NSEC_MASK) >> EXT4_EPOCH_BITS;
 }
 
 #define EXT4_INODE_SET_XTIME(xtime, inode, raw_inode)			       \
@@ -672,6 +697,11 @@ struct ext4_inode_info {
 	__u16 i_extra_isize;
 
 	spinlock_t i_block_reservation_lock;
+
+	/* completed async DIOs that might need unwritten extents handling */
+	struct list_head i_aio_dio_complete_list;
+	/* current io_end structure for async DIO write*/
+	ext4_io_end_t *cur_aio_dio;
 };
 
 /*
@@ -942,18 +972,11 @@ struct ext4_sb_info {
 	unsigned int s_mb_stats;
 	unsigned int s_mb_order2_reqs;
 	unsigned int s_mb_group_prealloc;
+	unsigned int s_max_writeback_mb_bump;
 	/* where last allocation was done - for stream allocation */
 	unsigned long s_mb_last_group;
 	unsigned long s_mb_last_start;
 
-	/* history to debug policy */
-	struct ext4_mb_history *s_mb_history;
-	int s_mb_history_cur;
-	int s_mb_history_max;
-	int s_mb_history_num;
-	spinlock_t s_mb_history_lock;
-	int s_mb_history_filter;
-
 	/* stats for buddy allocator */
 	spinlock_t s_mb_pa_lock;
 	atomic_t s_bal_reqs;	/* number of reqs with len > 1 */
@@ -980,6 +1003,9 @@ struct ext4_sb_info {
 
 	unsigned int s_log_groups_per_flex;
 	struct flex_groups *s_flex_groups;
+
+	/* workqueue for dio unwritten */
+	struct workqueue_struct *dio_unwritten_wq;
 };
 
 static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb)
@@ -1397,7 +1423,7 @@ extern int ext4_block_truncate_page(handle_t *handle,
 		struct address_space *mapping, loff_t from);
 extern int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
 extern qsize_t ext4_get_reserved_space(struct inode *inode);
-
+extern int flush_aio_dio_completed_IO(struct inode *inode);
 /* ioctl.c */
 extern long ext4_ioctl(struct file *, unsigned int, unsigned long);
 extern long ext4_compat_ioctl(struct file *, unsigned int, unsigned long);
@@ -1699,6 +1725,8 @@ extern void ext4_ext_init(struct super_block *);
 extern void ext4_ext_release(struct super_block *);
 extern long ext4_fallocate(struct inode *inode, int mode, loff_t offset,
 			  loff_t len);
+extern int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
+			  loff_t len);
 extern int ext4_get_blocks(handle_t *handle, struct inode *inode,
 			   sector_t block, unsigned int max_blocks,
 			   struct buffer_head *bh, int flags);
diff --git a/fs/ext4/ext4_extents.h b/fs/ext4/ext4_extents.h
index 61652f1..2ca6864 100644
--- a/fs/ext4/ext4_extents.h
+++ b/fs/ext4/ext4_extents.h
@@ -220,6 +220,11 @@ static inline int ext4_ext_get_actual_len(struct ext4_extent *ext)
 		(le16_to_cpu(ext->ee_len) - EXT_INIT_MAX_LEN));
 }
 
+static inline void ext4_ext_mark_initialized(struct ext4_extent *ext)
+{
+	ext->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ext));
+}
+
 extern int ext4_ext_calc_metadata_amount(struct inode *inode, int blocks);
 extern ext4_fsblk_t ext_pblock(struct ext4_extent *ex);
 extern ext4_fsblk_t idx_pblock(struct ext4_extent_idx *);
@@ -235,7 +240,7 @@ extern int ext4_ext_try_to_merge(struct inode *inode,
 				 struct ext4_ext_path *path,
 				 struct ext4_extent *);
 extern unsigned int ext4_ext_check_overlap(struct inode *, struct ext4_extent *, struct ext4_ext_path *);
-extern int ext4_ext_insert_extent(handle_t *, struct inode *, struct ext4_ext_path *, struct ext4_extent *);
+extern int ext4_ext_insert_extent(handle_t *, struct inode *, struct ext4_ext_path *, struct ext4_extent *, int);
 extern int ext4_ext_walk_space(struct inode *, ext4_lblk_t, ext4_lblk_t,
 							ext_prepare_callback, void *);
 extern struct ext4_ext_path *ext4_ext_find_extent(struct inode *, ext4_lblk_t,
diff --git a/fs/ext4/ext4_jbd2.h b/fs/ext4/ext4_jbd2.h
index 139fb8c..a286598 100644
--- a/fs/ext4/ext4_jbd2.h
+++ b/fs/ext4/ext4_jbd2.h
@@ -161,11 +161,13 @@ int __ext4_handle_dirty_metadata(const char *where, handle_t *handle,
 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks);
 int __ext4_journal_stop(const char *where, handle_t *handle);
 
-#define EXT4_NOJOURNAL_HANDLE	((handle_t *) 0x1)
+#define EXT4_NOJOURNAL_MAX_REF_COUNT ((unsigned long) 4096)
 
+/* Note:  Do not use this for NULL handles.  This is only to determine if
+ * a properly allocated handle is using a journal or not. */
 static inline int ext4_handle_valid(handle_t *handle)
 {
-	if (handle == EXT4_NOJOURNAL_HANDLE)
+	if ((unsigned long)handle < EXT4_NOJOURNAL_MAX_REF_COUNT)
 		return 0;
 	return 1;
 }
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 7a38325..10539e3 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -723,7 +723,7 @@ err:
  * insert new index [@logical;@ptr] into the block at @curp;
  * check where to insert: before @curp or after @curp
  */
-static int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
+int ext4_ext_insert_index(handle_t *handle, struct inode *inode,
 				struct ext4_ext_path *curp,
 				int logical, ext4_fsblk_t ptr)
 {
@@ -1586,7 +1586,7 @@ out:
  */
 int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
 				struct ext4_ext_path *path,
-				struct ext4_extent *newext)
+				struct ext4_extent *newext, int flag)
 {
 	struct ext4_extent_header *eh;
 	struct ext4_extent *ex, *fex;
@@ -1602,7 +1602,8 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
 	BUG_ON(path[depth].p_hdr == NULL);
 
 	/* try to insert block into found extent and return */
-	if (ex && ext4_can_extents_be_merged(inode, ex, newext)) {
+	if (ex && (flag != EXT4_GET_BLOCKS_DIO_CREATE_EXT)
+		&& ext4_can_extents_be_merged(inode, ex, newext)) {
 		ext_debug("append [%d]%d block to %d:[%d]%d (from %llu)\n",
 				ext4_ext_is_uninitialized(newext),
 				ext4_ext_get_actual_len(newext),
@@ -1722,7 +1723,8 @@ has_space:
 
 merge:
 	/* try to merge extents to the right */
-	ext4_ext_try_to_merge(inode, path, nearex);
+	if (flag != EXT4_GET_BLOCKS_DIO_CREATE_EXT)
+		ext4_ext_try_to_merge(inode, path, nearex);
 
 	/* try to merge extents to the left */
 
@@ -2378,6 +2380,7 @@ void ext4_ext_init(struct super_block *sb)
 	 */
 
 	if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
+#if defined(AGGRESSIVE_TEST) || defined(CHECK_BINSEARCH) || defined(EXTENTS_STATS)
 		printk(KERN_INFO "EXT4-fs: file extents enabled");
 #ifdef AGGRESSIVE_TEST
 		printk(", aggressive tests");
@@ -2389,6 +2392,7 @@ void ext4_ext_init(struct super_block *sb)
 		printk(", stats");
 #endif
 		printk("\n");
+#endif
 #ifdef EXTENTS_STATS
 		spin_lock_init(&EXT4_SB(sb)->s_ext_stats_lock);
 		EXT4_SB(sb)->s_ext_min = 1 << 30;
@@ -2490,7 +2494,6 @@ static int ext4_ext_zeroout(struct inode *inode, struct ext4_extent *ex)
 }
 
 #define EXT4_EXT_ZERO_LEN 7
-
 /*
  * This function is called by ext4_ext_get_blocks() if someone tries to write
  * to an uninitialized extent. It may result in splitting the uninitialized
@@ -2583,7 +2586,8 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
 			ex3->ee_block = cpu_to_le32(iblock);
 			ext4_ext_store_pblock(ex3, newblock);
 			ex3->ee_len = cpu_to_le16(allocated);
-			err = ext4_ext_insert_extent(handle, inode, path, ex3);
+			err = ext4_ext_insert_extent(handle, inode, path,
+							ex3, 0);
 			if (err == -ENOSPC) {
 				err =  ext4_ext_zeroout(inode, &orig_ex);
 				if (err)
@@ -2639,7 +2643,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
 		ext4_ext_store_pblock(ex3, newblock + max_blocks);
 		ex3->ee_len = cpu_to_le16(allocated - max_blocks);
 		ext4_ext_mark_uninitialized(ex3);
-		err = ext4_ext_insert_extent(handle, inode, path, ex3);
+		err = ext4_ext_insert_extent(handle, inode, path, ex3, 0);
 		if (err == -ENOSPC) {
 			err =  ext4_ext_zeroout(inode, &orig_ex);
 			if (err)
@@ -2757,7 +2761,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
 	err = ext4_ext_dirty(handle, inode, path + depth);
 	goto out;
 insert:
-	err = ext4_ext_insert_extent(handle, inode, path, &newex);
+	err = ext4_ext_insert_extent(handle, inode, path, &newex, 0);
 	if (err == -ENOSPC) {
 		err =  ext4_ext_zeroout(inode, &orig_ex);
 		if (err)
@@ -2785,6 +2789,324 @@ fix_extent_len:
 }
 
 /*
+ * This function is called by ext4_ext_get_blocks() from
+ * ext4_get_blocks_dio_write() when DIO to write
+ * to an uninitialized extent.
+ *
+ * Writing to an uninitized extent may result in splitting the uninitialized
+ * extent into multiple /intialized unintialized extents (up to three)
+ * There are three possibilities:
+ *   a> There is no split required: Entire extent should be uninitialized
+ *   b> Splits in two extents: Write is happening at either end of the extent
+ *   c> Splits in three extents: Somone is writing in middle of the extent
+ *
+ * One of more index blocks maybe needed if the extent tree grow after
+ * the unintialized extent split. To prevent ENOSPC occur at the IO
+ * complete, we need to split the uninitialized extent before DIO submit
+ * the IO. The uninitilized extent called at this time will be split
+ * into three uninitialized extent(at most). After IO complete, the part
+ * being filled will be convert to initialized by the end_io callback function
+ * via ext4_convert_unwritten_extents().
+ */
+static int ext4_split_unwritten_extents(handle_t *handle,
+					struct inode *inode,
+					struct ext4_ext_path *path,
+					ext4_lblk_t iblock,
+					unsigned int max_blocks,
+					int flags)
+{
+	struct ext4_extent *ex, newex, orig_ex;
+	struct ext4_extent *ex1 = NULL;
+	struct ext4_extent *ex2 = NULL;
+	struct ext4_extent *ex3 = NULL;
+	struct ext4_extent_header *eh;
+	ext4_lblk_t ee_block;
+	unsigned int allocated, ee_len, depth;
+	ext4_fsblk_t newblock;
+	int err = 0;
+	int ret = 0;
+
+	ext_debug("ext4_split_unwritten_extents: inode %lu,"
+		  "iblock %llu, max_blocks %u\n", inode->i_ino,
+		  (unsigned long long)iblock, max_blocks);
+	depth = ext_depth(inode);
+	eh = path[depth].p_hdr;
+	ex = path[depth].p_ext;
+	ee_block = le32_to_cpu(ex->ee_block);
+	ee_len = ext4_ext_get_actual_len(ex);
+	allocated = ee_len - (iblock - ee_block);
+	newblock = iblock - ee_block + ext_pblock(ex);
+	ex2 = ex;
+	orig_ex.ee_block = ex->ee_block;
+	orig_ex.ee_len   = cpu_to_le16(ee_len);
+	ext4_ext_store_pblock(&orig_ex, ext_pblock(ex));
+
+	/*
+ 	 * if the entire unintialized extent length less than
+ 	 * the size of extent to write, there is no need to split
+ 	 * uninitialized extent
+ 	 */
+ 	if (allocated <= max_blocks)
+		return ret;
+
+	err = ext4_ext_get_access(handle, inode, path + depth);
+	if (err)
+		goto out;
+	/* ex1: ee_block to iblock - 1 : uninitialized */
+	if (iblock > ee_block) {
+		ex1 = ex;
+		ex1->ee_len = cpu_to_le16(iblock - ee_block);
+		ext4_ext_mark_uninitialized(ex1);
+		ex2 = &newex;
+	}
+	/*
+	 * for sanity, update the length of the ex2 extent before
+	 * we insert ex3, if ex1 is NULL. This is to avoid temporary
+	 * overlap of blocks.
+	 */
+	if (!ex1 && allocated > max_blocks)
+		ex2->ee_len = cpu_to_le16(max_blocks);
+	/* ex3: to ee_block + ee_len : uninitialised */
+	if (allocated > max_blocks) {
+		unsigned int newdepth;
+		ex3 = &newex;
+		ex3->ee_block = cpu_to_le32(iblock + max_blocks);
+		ext4_ext_store_pblock(ex3, newblock + max_blocks);
+		ex3->ee_len = cpu_to_le16(allocated - max_blocks);
+		ext4_ext_mark_uninitialized(ex3);
+		err = ext4_ext_insert_extent(handle, inode, path, ex3, flags);
+		if (err == -ENOSPC) {
+			err =  ext4_ext_zeroout(inode, &orig_ex);
+			if (err)
+				goto fix_extent_len;
+			/* update the extent length and mark as initialized */
+			ex->ee_block = orig_ex.ee_block;
+			ex->ee_len   = orig_ex.ee_len;
+			ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
+			ext4_ext_dirty(handle, inode, path + depth);
+			/* zeroed the full extent */
+			/* blocks available from iblock */
+			return allocated;
+
+		} else if (err)
+			goto fix_extent_len;
+		/*
+		 * The depth, and hence eh & ex might change
+		 * as part of the insert above.
+		 */
+		newdepth = ext_depth(inode);
+		/*
+		 * update the extent length after successful insert of the
+		 * split extent
+		 */
+		orig_ex.ee_len = cpu_to_le16(ee_len -
+						ext4_ext_get_actual_len(ex3));
+		depth = newdepth;
+		ext4_ext_drop_refs(path);
+		path = ext4_ext_find_extent(inode, iblock, path);
+		if (IS_ERR(path)) {
+			err = PTR_ERR(path);
+			goto out;
+		}
+		eh = path[depth].p_hdr;
+		ex = path[depth].p_ext;
+		if (ex2 != &newex)
+			ex2 = ex;
+
+		err = ext4_ext_get_access(handle, inode, path + depth);
+		if (err)
+			goto out;
+
+		allocated = max_blocks;
+	}
+	/*
+	 * If there was a change of depth as part of the
+	 * insertion of ex3 above, we need to update the length
+	 * of the ex1 extent again here
+	 */
+	if (ex1 && ex1 != ex) {
+		ex1 = ex;
+		ex1->ee_len = cpu_to_le16(iblock - ee_block);
+		ext4_ext_mark_uninitialized(ex1);
+		ex2 = &newex;
+	}
+	/*
+	 * ex2: iblock to iblock + maxblocks-1 : to be direct IO written,
+	 * uninitialised still.
+	 */
+	ex2->ee_block = cpu_to_le32(iblock);
+	ext4_ext_store_pblock(ex2, newblock);
+	ex2->ee_len = cpu_to_le16(allocated);
+	ext4_ext_mark_uninitialized(ex2);
+	if (ex2 != ex)
+		goto insert;
+	/* Mark modified extent as dirty */
+	err = ext4_ext_dirty(handle, inode, path + depth);
+	ext_debug("out here\n");
+	goto out;
+insert:
+	err = ext4_ext_insert_extent(handle, inode, path, &newex, flags);
+	if (err == -ENOSPC) {
+		err =  ext4_ext_zeroout(inode, &orig_ex);
+		if (err)
+			goto fix_extent_len;
+		/* update the extent length and mark as initialized */
+		ex->ee_block = orig_ex.ee_block;
+		ex->ee_len   = orig_ex.ee_len;
+		ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
+		ext4_ext_dirty(handle, inode, path + depth);
+		/* zero out the first half */
+		return allocated;
+	} else if (err)
+		goto fix_extent_len;
+out:
+	ext4_ext_show_leaf(inode, path);
+	return err ? err : allocated;
+
+fix_extent_len:
+	ex->ee_block = orig_ex.ee_block;
+	ex->ee_len   = orig_ex.ee_len;
+	ext4_ext_store_pblock(ex, ext_pblock(&orig_ex));
+	ext4_ext_mark_uninitialized(ex);
+	ext4_ext_dirty(handle, inode, path + depth);
+	return err;
+}
+static int ext4_convert_unwritten_extents_dio(handle_t *handle,
+					      struct inode *inode,
+					      struct ext4_ext_path *path)
+{
+	struct ext4_extent *ex;
+	struct ext4_extent_header *eh;
+	int depth;
+	int err = 0;
+	int ret = 0;
+
+	depth = ext_depth(inode);
+	eh = path[depth].p_hdr;
+	ex = path[depth].p_ext;
+
+	err = ext4_ext_get_access(handle, inode, path + depth);
+	if (err)
+		goto out;
+	/* first mark the extent as initialized */
+	ext4_ext_mark_initialized(ex);
+
+	/*
+	 * We have to see if it can be merged with the extent
+	 * on the left.
+	 */
+	if (ex > EXT_FIRST_EXTENT(eh)) {
+		/*
+		 * To merge left, pass "ex - 1" to try_to_merge(),
+		 * since it merges towards right _only_.
+		 */
+		ret = ext4_ext_try_to_merge(inode, path, ex - 1);
+		if (ret) {
+			err = ext4_ext_correct_indexes(handle, inode, path);
+			if (err)
+				goto out;
+			depth = ext_depth(inode);
+			ex--;
+		}
+	}
+	/*
+	 * Try to Merge towards right.
+	 */
+	ret = ext4_ext_try_to_merge(inode, path, ex);
+	if (ret) {
+		err = ext4_ext_correct_indexes(handle, inode, path);
+		if (err)
+			goto out;
+		depth = ext_depth(inode);
+	}
+	/* Mark modified extent as dirty */
+	err = ext4_ext_dirty(handle, inode, path + depth);
+out:
+	ext4_ext_show_leaf(inode, path);
+	return err;
+}
+
+static int
+ext4_ext_handle_uninitialized_extents(handle_t *handle, struct inode *inode,
+			ext4_lblk_t iblock, unsigned int max_blocks,
+			struct ext4_ext_path *path, int flags,
+			unsigned int allocated, struct buffer_head *bh_result,
+			ext4_fsblk_t newblock)
+{
+	int ret = 0;
+	int err = 0;
+	ext4_io_end_t *io = EXT4_I(inode)->cur_aio_dio;
+
+	ext_debug("ext4_ext_handle_uninitialized_extents: inode %lu, logical"
+		  "block %llu, max_blocks %u, flags %d, allocated %u",
+		  inode->i_ino, (unsigned long long)iblock, max_blocks,
+		  flags, allocated);
+	ext4_ext_show_leaf(inode, path);
+
+	/* DIO get_block() before submit the IO, split the extent */
+	if (flags == EXT4_GET_BLOCKS_DIO_CREATE_EXT) {
+		ret = ext4_split_unwritten_extents(handle,
+						inode, path, iblock,
+						max_blocks, flags);
+		/* flag the io_end struct that we need convert when IO done */
+		if (io)
+			io->flag = DIO_AIO_UNWRITTEN;
+		goto out;
+	}
+	/* DIO end_io complete, convert the filled extent to written */
+	if (flags == EXT4_GET_BLOCKS_DIO_CONVERT_EXT) {
+		ret = ext4_convert_unwritten_extents_dio(handle, inode,
+							path);
+		goto out2;
+	}
+	/* buffered IO case */
+	/*
+	 * repeat fallocate creation request
+	 * we already have an unwritten extent
+	 */
+	if (flags & EXT4_GET_BLOCKS_UNINIT_EXT)
+		goto map_out;
+
+	/* buffered READ or buffered write_begin() lookup */
+	if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
+		/*
+		 * We have blocks reserved already.  We
+		 * return allocated blocks so that delalloc
+		 * won't do block reservation for us.  But
+		 * the buffer head will be unmapped so that
+		 * a read from the block returns 0s.
+		 */
+		set_buffer_unwritten(bh_result);
+		goto out1;
+	}
+
+	/* buffered write, writepage time, convert*/
+	ret = ext4_ext_convert_to_initialized(handle, inode,
+						path, iblock,
+						max_blocks);
+out:
+	if (ret <= 0) {
+		err = ret;
+		goto out2;
+	} else
+		allocated = ret;
+	set_buffer_new(bh_result);
+map_out:
+	set_buffer_mapped(bh_result);
+out1:
+	if (allocated > max_blocks)
+		allocated = max_blocks;
+	ext4_ext_show_leaf(inode, path);
+	bh_result->b_bdev = inode->i_sb->s_bdev;
+	bh_result->b_blocknr = newblock;
+out2:
+	if (path) {
+		ext4_ext_drop_refs(path);
+		kfree(path);
+	}
+	return err ? err : allocated;
+}
+/*
  * Block allocation/map/preallocation routine for extents based files
  *
  *
@@ -2814,6 +3136,7 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
 	int err = 0, depth, ret, cache_type;
 	unsigned int allocated = 0;
 	struct ext4_allocation_request ar;
+	ext4_io_end_t *io = EXT4_I(inode)->cur_aio_dio;
 
 	__clear_bit(BH_New, &bh_result->b_state);
 	ext_debug("blocks %u/%u requested for inode %lu\n",
@@ -2889,33 +3212,10 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
 							EXT4_EXT_CACHE_EXTENT);
 				goto out;
 			}
-			if (flags & EXT4_GET_BLOCKS_UNINIT_EXT)
-				goto out;
-			if ((flags & EXT4_GET_BLOCKS_CREATE) == 0) {
-				if (allocated > max_blocks)
-					allocated = max_blocks;
-				/*
-				 * We have blocks reserved already.  We
-				 * return allocated blocks so that delalloc
-				 * won't do block reservation for us.  But
-				 * the buffer head will be unmapped so that
-				 * a read from the block returns 0s.
-				 */
-				set_buffer_unwritten(bh_result);
-				bh_result->b_bdev = inode->i_sb->s_bdev;
-				bh_result->b_blocknr = newblock;
-				goto out2;
-			}
-
-			ret = ext4_ext_convert_to_initialized(handle, inode,
-								path, iblock,
-								max_blocks);
-			if (ret <= 0) {
-				err = ret;
-				goto out2;
-			} else
-				allocated = ret;
-			goto outnew;
+			ret = ext4_ext_handle_uninitialized_extents(handle,
+					inode, iblock, max_blocks, path,
+					flags, allocated, bh_result, newblock);
+			return ret;
 		}
 	}
 
@@ -2986,9 +3286,21 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
 	/* try to insert new extent into found leaf and return */
 	ext4_ext_store_pblock(&newex, newblock);
 	newex.ee_len = cpu_to_le16(ar.len);
-	if (flags & EXT4_GET_BLOCKS_UNINIT_EXT)  /* Mark uninitialized */
+	/* Mark uninitialized */
+	if (flags & EXT4_GET_BLOCKS_UNINIT_EXT){
 		ext4_ext_mark_uninitialized(&newex);
-	err = ext4_ext_insert_extent(handle, inode, path, &newex);
+		/*
+		 * io_end structure was created for every async
+		 * direct IO write to the middle of the file.
+		 * To avoid unecessary convertion for every aio dio rewrite
+		 * to the mid of file, here we flag the IO that is really
+		 * need the convertion.
+		 *
+		 */
+		if (io && flags == EXT4_GET_BLOCKS_DIO_CREATE_EXT)
+			io->flag = DIO_AIO_UNWRITTEN;
+	}
+	err = ext4_ext_insert_extent(handle, inode, path, &newex, flags);
 	if (err) {
 		/* free data blocks we just allocated */
 		/* not a good idea to call discard here directly,
@@ -3002,7 +3314,6 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
 	/* previous routine could use block we allocated */
 	newblock = ext_pblock(&newex);
 	allocated = ext4_ext_get_actual_len(&newex);
-outnew:
 	set_buffer_new(bh_result);
 
 	/* Cache only when it is _not_ an uninitialized extent */
@@ -3201,6 +3512,63 @@ retry:
 }
 
 /*
+ * This function convert a range of blocks to written extents
+ * The caller of this function will pass the start offset and the size.
+ * all unwritten extents within this range will be converted to
+ * written extents.
+ *
+ * This function is called from the direct IO end io call back
+ * function, to convert the fallocated extents after IO is completed.
+ */
+int ext4_convert_unwritten_extents(struct inode *inode, loff_t offset,
+				    loff_t len)
+{
+	handle_t *handle;
+	ext4_lblk_t block;
+	unsigned int max_blocks;
+	int ret = 0;
+	int ret2 = 0;
+	struct buffer_head map_bh;
+	unsigned int credits, blkbits = inode->i_blkbits;
+
+	block = offset >> blkbits;
+	/*
+	 * We can't just convert len to max_blocks because
+	 * If blocksize = 4096 offset = 3072 and len = 2048
+	 */
+	max_blocks = (EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits)
+							- block;
+	/*
+	 * credits to insert 1 extent into extent tree
+	 */
+	credits = ext4_chunk_trans_blocks(inode, max_blocks);
+	while (ret >= 0 && ret < max_blocks) {
+		block = block + ret;
+		max_blocks = max_blocks - ret;
+		handle = ext4_journal_start(inode, credits);
+		if (IS_ERR(handle)) {
+			ret = PTR_ERR(handle);
+			break;
+		}
+		map_bh.b_state = 0;
+		ret = ext4_get_blocks(handle, inode, block,
+				      max_blocks, &map_bh,
+				      EXT4_GET_BLOCKS_DIO_CONVERT_EXT);
+		if (ret <= 0) {
+			WARN_ON(ret <= 0);
+			printk(KERN_ERR "%s: ext4_ext_get_blocks "
+				    "returned error inode#%lu, block=%u, "
+				    "max_blocks=%u", __func__,
+				    inode->i_ino, block, max_blocks);
+		}
+		ext4_mark_inode_dirty(handle, inode);
+		ret2 = ext4_journal_stop(handle);
+		if (ret <= 0 || ret2 )
+			break;
+	}
+	return ret > 0 ? ret2 : ret;
+}
+/*
  * Callback function called for each extent to gather FIEMAP information.
  */
 static int ext4_ext_fiemap_cb(struct inode *inode, struct ext4_ext_path *path,
diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 5ca3eca..9630583 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -81,7 +81,7 @@ ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
 	return generic_file_aio_write(iocb, iov, nr_segs, pos);
 }
 
-static struct vm_operations_struct ext4_file_vm_ops = {
+static const struct vm_operations_struct ext4_file_vm_ops = {
 	.fault		= filemap_fault,
 	.page_mkwrite   = ext4_page_mkwrite,
 };
diff --git a/fs/ext4/fsync.c b/fs/ext4/fsync.c
index 0747574..2b15312 100644
--- a/fs/ext4/fsync.c
+++ b/fs/ext4/fsync.c
@@ -44,6 +44,8 @@
  *
  * What we do is just kick off a commit and wait on it.  This will snapshot the
  * inode to disk.
+ *
+ * i_mutex lock is held when entering and exiting this function
  */
 
 int ext4_sync_file(struct file *file, struct dentry *dentry, int datasync)
@@ -56,6 +58,9 @@ int ext4_sync_file(struct file *file, struct dentry *dentry, int datasync)
 
 	trace_ext4_sync_file(file, dentry, datasync);
 
+	ret = flush_aio_dio_completed_IO(inode);
+	if (ret < 0)
+		goto out;
 	/*
 	 * data=writeback:
 	 *  The caller's filemap_fdatawrite()/wait will sync the data.
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 3a79873..5c5bc5d 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -37,6 +37,7 @@
 #include <linux/namei.h>
 #include <linux/uio.h>
 #include <linux/bio.h>
+#include <linux/workqueue.h>
 
 #include "ext4_jbd2.h"
 #include "xattr.h"
@@ -1145,6 +1146,64 @@ static int check_block_validity(struct inode *inode, const char *msg,
 }
 
 /*
+ * Return the number of contiguous dirty pages in a given inode
+ * starting at page frame idx.
+ */
+static pgoff_t ext4_num_dirty_pages(struct inode *inode, pgoff_t idx,
+				    unsigned int max_pages)
+{
+	struct address_space *mapping = inode->i_mapping;
+	pgoff_t	index;
+	struct pagevec pvec;
+	pgoff_t num = 0;
+	int i, nr_pages, done = 0;
+
+	if (max_pages == 0)
+		return 0;
+	pagevec_init(&pvec, 0);
+	while (!done) {
+		index = idx;
+		nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
+					      PAGECACHE_TAG_DIRTY,
+					      (pgoff_t)PAGEVEC_SIZE);
+		if (nr_pages == 0)
+			break;
+		for (i = 0; i < nr_pages; i++) {
+			struct page *page = pvec.pages[i];
+			struct buffer_head *bh, *head;
+
+			lock_page(page);
+			if (unlikely(page->mapping != mapping) ||
+			    !PageDirty(page) ||
+			    PageWriteback(page) ||
+			    page->index != idx) {
+				done = 1;
+				unlock_page(page);
+				break;
+			}
+			if (page_has_buffers(page)) {
+				bh = head = page_buffers(page);
+				do {
+					if (!buffer_delay(bh) &&
+					    !buffer_unwritten(bh))
+						done = 1;
+					bh = bh->b_this_page;
+				} while (!done && (bh != head));
+			}
+			unlock_page(page);
+			if (done)
+				break;
+			idx++;
+			num++;
+			if (num >= max_pages)
+				break;
+		}
+		pagevec_release(&pvec);
+	}
+	return num;
+}
+
+/*
  * The ext4_get_blocks() function tries to look up the requested blocks,
  * and returns if the blocks are already mapped.
  *
@@ -1175,6 +1234,9 @@ int ext4_get_blocks(handle_t *handle, struct inode *inode, sector_t block,
 	clear_buffer_mapped(bh);
 	clear_buffer_unwritten(bh);
 
+	ext_debug("ext4_get_blocks(): inode %lu, flag %d, max_blocks %u,"
+		  "logical block %lu\n", inode->i_ino, flags, max_blocks,
+		  (unsigned long)block);
 	/*
 	 * Try to see if we can get the block without requesting a new
 	 * file system block.
@@ -1796,11 +1858,11 @@ repeat:
 
 	if (ext4_claim_free_blocks(sbi, total)) {
 		spin_unlock(&EXT4_I(inode)->i_block_reservation_lock);
+		vfs_dq_release_reservation_block(inode, total);
 		if (ext4_should_retry_alloc(inode->i_sb, &retries)) {
 			yield();
 			goto repeat;
 		}
-		vfs_dq_release_reservation_block(inode, total);
 		return -ENOSPC;
 	}
 	EXT4_I(inode)->i_reserved_data_blocks += nrblocks;
@@ -2092,18 +2154,18 @@ static void ext4_da_block_invalidatepages(struct mpage_da_data *mpd,
 static void ext4_print_free_blocks(struct inode *inode)
 {
 	struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
-	printk(KERN_EMERG "Total free blocks count %lld\n",
-			ext4_count_free_blocks(inode->i_sb));
-	printk(KERN_EMERG "Free/Dirty block details\n");
-	printk(KERN_EMERG "free_blocks=%lld\n",
-			(long long)percpu_counter_sum(&sbi->s_freeblocks_counter));
-	printk(KERN_EMERG "dirty_blocks=%lld\n",
-			(long long)percpu_counter_sum(&sbi->s_dirtyblocks_counter));
-	printk(KERN_EMERG "Block reservation details\n");
-	printk(KERN_EMERG "i_reserved_data_blocks=%u\n",
-			EXT4_I(inode)->i_reserved_data_blocks);
-	printk(KERN_EMERG "i_reserved_meta_blocks=%u\n",
-			EXT4_I(inode)->i_reserved_meta_blocks);
+	printk(KERN_CRIT "Total free blocks count %lld\n",
+	       ext4_count_free_blocks(inode->i_sb));
+	printk(KERN_CRIT "Free/Dirty block details\n");
+	printk(KERN_CRIT "free_blocks=%lld\n",
+	       (long long) percpu_counter_sum(&sbi->s_freeblocks_counter));
+	printk(KERN_CRIT "dirty_blocks=%lld\n",
+	       (long long) percpu_counter_sum(&sbi->s_dirtyblocks_counter));
+	printk(KERN_CRIT "Block reservation details\n");
+	printk(KERN_CRIT "i_reserved_data_blocks=%u\n",
+	       EXT4_I(inode)->i_reserved_data_blocks);
+	printk(KERN_CRIT "i_reserved_meta_blocks=%u\n",
+	       EXT4_I(inode)->i_reserved_meta_blocks);
 	return;
 }
 
@@ -2189,14 +2251,14 @@ static int mpage_da_map_blocks(struct mpage_da_data *mpd)
 		 * writepage and writepages will again try to write
 		 * the same.
 		 */
-		printk(KERN_EMERG "%s block allocation failed for inode %lu "
-				  "at logical offset %llu with max blocks "
-				  "%zd with error %d\n",
-				  __func__, mpd->inode->i_ino,
-				  (unsigned long long)next,
-				  mpd->b_size >> mpd->inode->i_blkbits, err);
-		printk(KERN_EMERG "This should not happen.!! "
-					"Data will be lost\n");
+		ext4_msg(mpd->inode->i_sb, KERN_CRIT,
+			 "delayed block allocation failed for inode %lu at "
+			 "logical offset %llu with max blocks %zd with "
+			 "error %d\n", mpd->inode->i_ino,
+			 (unsigned long long) next,
+			 mpd->b_size >> mpd->inode->i_blkbits, err);
+		printk(KERN_CRIT "This should not happen!!  "
+		       "Data will be lost\n");
 		if (err == -ENOSPC) {
 			ext4_print_free_blocks(mpd->inode);
 		}
@@ -2743,8 +2805,10 @@ static int ext4_da_writepages(struct address_space *mapping,
 	int no_nrwrite_index_update;
 	int pages_written = 0;
 	long pages_skipped;
+	unsigned int max_pages;
 	int range_cyclic, cycled = 1, io_done = 0;
-	int needed_blocks, ret = 0, nr_to_writebump = 0;
+	int needed_blocks, ret = 0;
+	long desired_nr_to_write, nr_to_writebump = 0;
 	loff_t range_start = wbc->range_start;
 	struct ext4_sb_info *sbi = EXT4_SB(mapping->host->i_sb);
 
@@ -2771,16 +2835,6 @@ static int ext4_da_writepages(struct address_space *mapping,
 	if (unlikely(sbi->s_mount_flags & EXT4_MF_FS_ABORTED))
 		return -EROFS;
 
-	/*
-	 * Make sure nr_to_write is >= sbi->s_mb_stream_request
-	 * This make sure small files blocks are allocated in
-	 * single attempt. This ensure that small files
-	 * get less fragmented.
-	 */
-	if (wbc->nr_to_write < sbi->s_mb_stream_request) {
-		nr_to_writebump = sbi->s_mb_stream_request - wbc->nr_to_write;
-		wbc->nr_to_write = sbi->s_mb_stream_request;
-	}
 	if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
 		range_whole = 1;
 
@@ -2795,6 +2849,36 @@ static int ext4_da_writepages(struct address_space *mapping,
 	} else
 		index = wbc->range_start >> PAGE_CACHE_SHIFT;
 
+	/*
+	 * This works around two forms of stupidity.  The first is in
+	 * the writeback code, which caps the maximum number of pages
+	 * written to be 1024 pages.  This is wrong on multiple
+	 * levels; different architectues have a different page size,
+	 * which changes the maximum amount of data which gets
+	 * written.  Secondly, 4 megabytes is way too small.  XFS
+	 * forces this value to be 16 megabytes by multiplying
+	 * nr_to_write parameter by four, and then relies on its
+	 * allocator to allocate larger extents to make them
+	 * contiguous.  Unfortunately this brings us to the second
+	 * stupidity, which is that ext4's mballoc code only allocates
+	 * at most 2048 blocks.  So we force contiguous writes up to
+	 * the number of dirty blocks in the inode, or
+	 * sbi->max_writeback_mb_bump whichever is smaller.
+	 */
+	max_pages = sbi->s_max_writeback_mb_bump << (20 - PAGE_CACHE_SHIFT);
+	if (!range_cyclic && range_whole)
+		desired_nr_to_write = wbc->nr_to_write * 8;
+	else
+		desired_nr_to_write = ext4_num_dirty_pages(inode, index,
+							   max_pages);
+	if (desired_nr_to_write > max_pages)
+		desired_nr_to_write = max_pages;
+
+	if (wbc->nr_to_write < desired_nr_to_write) {
+		nr_to_writebump = desired_nr_to_write - wbc->nr_to_write;
+		wbc->nr_to_write = desired_nr_to_write;
+	}
+
 	mpd.wbc = wbc;
 	mpd.inode = mapping->host;
 
@@ -2822,10 +2906,9 @@ retry:
 		handle = ext4_journal_start(inode, needed_blocks);
 		if (IS_ERR(handle)) {
 			ret = PTR_ERR(handle);
-			printk(KERN_CRIT "%s: jbd2_start: "
+			ext4_msg(inode->i_sb, KERN_CRIT, "%s: jbd2_start: "
 			       "%ld pages, ino %lu; err %d\n", __func__,
 				wbc->nr_to_write, inode->i_ino, ret);
-			dump_stack();
 			goto out_writepages;
 		}
 
@@ -2897,9 +2980,10 @@ retry:
 		goto retry;
 	}
 	if (pages_skipped != wbc->pages_skipped)
-		printk(KERN_EMERG "This should not happen leaving %s "
-				"with nr_to_write = %ld ret = %d\n",
-				__func__, wbc->nr_to_write, ret);
+		ext4_msg(inode->i_sb, KERN_CRIT,
+			 "This should not happen leaving %s "
+			 "with nr_to_write = %ld ret = %d\n",
+			 __func__, wbc->nr_to_write, ret);
 
 	/* Update index */
 	index += pages_written;
@@ -2914,7 +2998,8 @@ retry:
 out_writepages:
 	if (!no_nrwrite_index_update)
 		wbc->no_nrwrite_index_update = 0;
-	wbc->nr_to_write -= nr_to_writebump;
+	if (wbc->nr_to_write > nr_to_writebump)
+		wbc->nr_to_write -= nr_to_writebump;
 	wbc->range_start = range_start;
 	trace_ext4_da_writepages_result(inode, wbc, ret, pages_written);
 	return ret;
@@ -3272,6 +3357,8 @@ static int ext4_releasepage(struct page *page, gfp_t wait)
 }
 
 /*
+ * O_DIRECT for ext3 (or indirect map) based files
+ *
  * If the O_DIRECT write will extend the file then add this inode to the
  * orphan list.  So recovery will truncate it back to the original size
  * if the machine crashes during the write.
@@ -3280,7 +3367,7 @@ static int ext4_releasepage(struct page *page, gfp_t wait)
  * crashes then stale disk data _may_ be exposed inside the file. But current
  * VFS code falls back into buffered path in that case so we are safe.
  */
-static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb,
+static ssize_t ext4_ind_direct_IO(int rw, struct kiocb *iocb,
 			      const struct iovec *iov, loff_t offset,
 			      unsigned long nr_segs)
 {
@@ -3291,6 +3378,7 @@ static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb,
 	ssize_t ret;
 	int orphan = 0;
 	size_t count = iov_length(iov, nr_segs);
+	int retries = 0;
 
 	if (rw == WRITE) {
 		loff_t final_size = offset + count;
@@ -3313,9 +3401,12 @@ static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb,
 		}
 	}
 
+retry:
 	ret = blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
 				 offset, nr_segs,
 				 ext4_get_block, NULL);
+	if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
+		goto retry;
 
 	if (orphan) {
 		int err;
@@ -3354,6 +3445,359 @@ out:
 	return ret;
 }
 
+/* Maximum number of blocks we map for direct IO at once. */
+
+static int ext4_get_block_dio_write(struct inode *inode, sector_t iblock,
+		   struct buffer_head *bh_result, int create)
+{
+	handle_t *handle = NULL;
+	int ret = 0;
+	unsigned max_blocks = bh_result->b_size >> inode->i_blkbits;
+	int dio_credits;
+
+	ext4_debug("ext4_get_block_dio_write: inode %lu, create flag %d\n",
+		   inode->i_ino, create);
+	/*
+	 * DIO VFS code passes create = 0 flag for write to
+	 * the middle of file. It does this to avoid block
+	 * allocation for holes, to prevent expose stale data
+	 * out when there is parallel buffered read (which does
+	 * not hold the i_mutex lock) while direct IO write has
+	 * not completed. DIO request on holes finally falls back
+	 * to buffered IO for this reason.
+	 *
+	 * For ext4 extent based file, since we support fallocate,
+	 * new allocated extent as uninitialized, for holes, we
+	 * could fallocate blocks for holes, thus parallel
+	 * buffered IO read will zero out the page when read on
+	 * a hole while parallel DIO write to the hole has not completed.
+	 *
+	 * when we come here, we know it's a direct IO write to
+	 * to the middle of file (<i_size)
+	 * so it's safe to override the create flag from VFS.
+	 */
+	create = EXT4_GET_BLOCKS_DIO_CREATE_EXT;
+
+	if (max_blocks > DIO_MAX_BLOCKS)
+		max_blocks = DIO_MAX_BLOCKS;
+	dio_credits = ext4_chunk_trans_blocks(inode, max_blocks);
+	handle = ext4_journal_start(inode, dio_credits);
+	if (IS_ERR(handle)) {
+		ret = PTR_ERR(handle);
+		goto out;
+	}
+	ret = ext4_get_blocks(handle, inode, iblock, max_blocks, bh_result,
+			      create);
+	if (ret > 0) {
+		bh_result->b_size = (ret << inode->i_blkbits);
+		ret = 0;
+	}
+	ext4_journal_stop(handle);
+out:
+	return ret;
+}
+
+static void ext4_free_io_end(ext4_io_end_t *io)
+{
+	BUG_ON(!io);
+	iput(io->inode);
+	kfree(io);
+}
+static void dump_aio_dio_list(struct inode * inode)
+{
+#ifdef	EXT4_DEBUG
+	struct list_head *cur, *before, *after;
+	ext4_io_end_t *io, *io0, *io1;
+
+	if (list_empty(&EXT4_I(inode)->i_aio_dio_complete_list)){
+		ext4_debug("inode %lu aio dio list is empty\n", inode->i_ino);
+		return;
+	}
+
+	ext4_debug("Dump inode %lu aio_dio_completed_IO list \n", inode->i_ino);
+	list_for_each_entry(io, &EXT4_I(inode)->i_aio_dio_complete_list, list){
+		cur = &io->list;
+		before = cur->prev;
+		io0 = container_of(before, ext4_io_end_t, list);
+		after = cur->next;
+		io1 = container_of(after, ext4_io_end_t, list);
+
+		ext4_debug("io 0x%p from inode %lu,prev 0x%p,next 0x%p\n",
+			    io, inode->i_ino, io0, io1);
+	}
+#endif
+}
+
+/*
+ * check a range of space and convert unwritten extents to written.
+ */
+static int ext4_end_aio_dio_nolock(ext4_io_end_t *io)
+{
+	struct inode *inode = io->inode;
+	loff_t offset = io->offset;
+	size_t size = io->size;
+	int ret = 0;
+
+	ext4_debug("end_aio_dio_onlock: io 0x%p from inode %lu,list->next 0x%p,"
+		   "list->prev 0x%p\n",
+	           io, inode->i_ino, io->list.next, io->list.prev);
+
+	if (list_empty(&io->list))
+		return ret;
+
+	if (io->flag != DIO_AIO_UNWRITTEN)
+		return ret;
+
+	if (offset + size <= i_size_read(inode))
+		ret = ext4_convert_unwritten_extents(inode, offset, size);
+
+	if (ret < 0) {
+		printk(KERN_EMERG "%s: failed to convert unwritten"
+			"extents to written extents, error is %d"
+			" io is still on inode %lu aio dio list\n",
+                       __func__, ret, inode->i_ino);
+		return ret;
+	}
+
+	/* clear the DIO AIO unwritten flag */
+	io->flag = 0;
+	return ret;
+}
+/*
+ * work on completed aio dio IO, to convert unwritten extents to extents
+ */
+static void ext4_end_aio_dio_work(struct work_struct *work)
+{
+	ext4_io_end_t *io  = container_of(work, ext4_io_end_t, work);
+	struct inode *inode = io->inode;
+	int ret = 0;
+
+	mutex_lock(&inode->i_mutex);
+	ret = ext4_end_aio_dio_nolock(io);
+	if (ret >= 0) {
+		if (!list_empty(&io->list))
+			list_del_init(&io->list);
+		ext4_free_io_end(io);
+	}
+	mutex_unlock(&inode->i_mutex);
+}
+/*
+ * This function is called from ext4_sync_file().
+ *
+ * When AIO DIO IO is completed, the work to convert unwritten
+ * extents to written is queued on workqueue but may not get immediately
+ * scheduled. When fsync is called, we need to ensure the
+ * conversion is complete before fsync returns.
+ * The inode keeps track of a list of completed AIO from DIO path
+ * that might needs to do the conversion. This function walks through
+ * the list and convert the related unwritten extents to written.
+ */
+int flush_aio_dio_completed_IO(struct inode *inode)
+{
+	ext4_io_end_t *io;
+	int ret = 0;
+	int ret2 = 0;
+
+	if (list_empty(&EXT4_I(inode)->i_aio_dio_complete_list))
+		return ret;
+
+	dump_aio_dio_list(inode);
+	while (!list_empty(&EXT4_I(inode)->i_aio_dio_complete_list)){
+		io = list_entry(EXT4_I(inode)->i_aio_dio_complete_list.next,
+				ext4_io_end_t, list);
+		/*
+		 * Calling ext4_end_aio_dio_nolock() to convert completed
+		 * IO to written.
+		 *
+		 * When ext4_sync_file() is called, run_queue() may already
+		 * about to flush the work corresponding to this io structure.
+		 * It will be upset if it founds the io structure related
+		 * to the work-to-be schedule is freed.
+		 *
+		 * Thus we need to keep the io structure still valid here after
+		 * convertion finished. The io structure has a flag to
+		 * avoid double converting from both fsync and background work
+		 * queue work.
+		 */
+		ret = ext4_end_aio_dio_nolock(io);
+		if (ret < 0)
+			ret2 = ret;
+		else
+			list_del_init(&io->list);
+	}
+	return (ret2 < 0) ? ret2 : 0;
+}
+
+static ext4_io_end_t *ext4_init_io_end (struct inode *inode)
+{
+	ext4_io_end_t *io = NULL;
+
+	io = kmalloc(sizeof(*io), GFP_NOFS);
+
+	if (io) {
+		igrab(inode);
+		io->inode = inode;
+		io->flag = 0;
+		io->offset = 0;
+		io->size = 0;
+		io->error = 0;
+		INIT_WORK(&io->work, ext4_end_aio_dio_work);
+		INIT_LIST_HEAD(&io->list);
+	}
+
+	return io;
+}
+
+static void ext4_end_io_dio(struct kiocb *iocb, loff_t offset,
+			    ssize_t size, void *private)
+{
+        ext4_io_end_t *io_end = iocb->private;
+	struct workqueue_struct *wq;
+
+	ext_debug("ext4_end_io_dio(): io_end 0x%p"
+		  "for inode %lu, iocb 0x%p, offset %llu, size %llu\n",
+ 		  iocb->private, io_end->inode->i_ino, iocb, offset,
+		  size);
+	/* if not async direct IO or dio with 0 bytes write, just return */
+	if (!io_end || !size)
+		return;
+
+	/* if not aio dio with unwritten extents, just free io and return */
+	if (io_end->flag != DIO_AIO_UNWRITTEN){
+		ext4_free_io_end(io_end);
+		iocb->private = NULL;
+		return;
+	}
+
+	io_end->offset = offset;
+	io_end->size = size;
+	wq = EXT4_SB(io_end->inode->i_sb)->dio_unwritten_wq;
+
+	/* queue the work to convert unwritten extents to written */
+	queue_work(wq, &io_end->work);
+
+	/* Add the io_end to per-inode completed aio dio list*/
+	list_add_tail(&io_end->list,
+		 &EXT4_I(io_end->inode)->i_aio_dio_complete_list);
+	iocb->private = NULL;
+}
+/*
+ * For ext4 extent files, ext4 will do direct-io write to holes,
+ * preallocated extents, and those write extend the file, no need to
+ * fall back to buffered IO.
+ *
+ * For holes, we fallocate those blocks, mark them as unintialized
+ * If those blocks were preallocated, we mark sure they are splited, but
+ * still keep the range to write as unintialized.
+ *
+ * The unwrritten extents will be converted to written when DIO is completed.
+ * For async direct IO, since the IO may still pending when return, we
+ * set up an end_io call back function, which will do the convertion
+ * when async direct IO completed.
+ *
+ * If the O_DIRECT write will extend the file then add this inode to the
+ * orphan list.  So recovery will truncate it back to the original size
+ * if the machine crashes during the write.
+ *
+ */
+static ssize_t ext4_ext_direct_IO(int rw, struct kiocb *iocb,
+			      const struct iovec *iov, loff_t offset,
+			      unsigned long nr_segs)
+{
+	struct file *file = iocb->ki_filp;
+	struct inode *inode = file->f_mapping->host;
+	ssize_t ret;
+	size_t count = iov_length(iov, nr_segs);
+
+	loff_t final_size = offset + count;
+	if (rw == WRITE && final_size <= inode->i_size) {
+		/*
+ 		 * We could direct write to holes and fallocate.
+		 *
+ 		 * Allocated blocks to fill the hole are marked as uninitialized
+ 		 * to prevent paralel buffered read to expose the stale data
+ 		 * before DIO complete the data IO.
+		 *
+ 		 * As to previously fallocated extents, ext4 get_block
+ 		 * will just simply mark the buffer mapped but still
+ 		 * keep the extents uninitialized.
+ 		 *
+		 * for non AIO case, we will convert those unwritten extents
+		 * to written after return back from blockdev_direct_IO.
+		 *
+		 * for async DIO, the conversion needs to be defered when
+		 * the IO is completed. The ext4 end_io callback function
+		 * will be called to take care of the conversion work.
+		 * Here for async case, we allocate an io_end structure to
+		 * hook to the iocb.
+ 		 */
+		iocb->private = NULL;
+		EXT4_I(inode)->cur_aio_dio = NULL;
+		if (!is_sync_kiocb(iocb)) {
+			iocb->private = ext4_init_io_end(inode);
+			if (!iocb->private)
+				return -ENOMEM;
+			/*
+			 * we save the io structure for current async
+			 * direct IO, so that later ext4_get_blocks()
+			 * could flag the io structure whether there
+			 * is a unwritten extents needs to be converted
+			 * when IO is completed.
+			 */
+			EXT4_I(inode)->cur_aio_dio = iocb->private;
+		}
+
+		ret = blockdev_direct_IO(rw, iocb, inode,
+					 inode->i_sb->s_bdev, iov,
+					 offset, nr_segs,
+					 ext4_get_block_dio_write,
+					 ext4_end_io_dio);
+		if (iocb->private)
+			EXT4_I(inode)->cur_aio_dio = NULL;
+		/*
+		 * The io_end structure takes a reference to the inode,
+		 * that structure needs to be destroyed and the
+		 * reference to the inode need to be dropped, when IO is
+		 * complete, even with 0 byte write, or failed.
+		 *
+		 * In the successful AIO DIO case, the io_end structure will be
+		 * desctroyed and the reference to the inode will be dropped
+		 * after the end_io call back function is called.
+		 *
+		 * In the case there is 0 byte write, or error case, since
+		 * VFS direct IO won't invoke the end_io call back function,
+		 * we need to free the end_io structure here.
+		 */
+		if (ret != -EIOCBQUEUED && ret <= 0 && iocb->private) {
+			ext4_free_io_end(iocb->private);
+			iocb->private = NULL;
+		} else if (ret > 0)
+			/*
+			 * for non AIO case, since the IO is already
+			 * completed, we could do the convertion right here
+			 */
+			ret = ext4_convert_unwritten_extents(inode,
+								offset, ret);
+		return ret;
+	}
+
+	/* for write the the end of file case, we fall back to old way */
+	return ext4_ind_direct_IO(rw, iocb, iov, offset, nr_segs);
+}
+
+static ssize_t ext4_direct_IO(int rw, struct kiocb *iocb,
+			      const struct iovec *iov, loff_t offset,
+			      unsigned long nr_segs)
+{
+	struct file *file = iocb->ki_filp;
+	struct inode *inode = file->f_mapping->host;
+
+	if (EXT4_I(inode)->i_flags & EXT4_EXTENTS_FL)
+		return ext4_ext_direct_IO(rw, iocb, iov, offset, nr_segs);
+
+	return ext4_ind_direct_IO(rw, iocb, iov, offset, nr_segs);
+}
+
 /*
  * Pages can be marked dirty completely asynchronously from ext4's journalling
  * activity.  By filemap_sync_pte(), try_to_unmap_one(), etc.  We cannot do
@@ -3386,6 +3830,7 @@ static const struct address_space_operations ext4_ordered_aops = {
 	.direct_IO		= ext4_direct_IO,
 	.migratepage		= buffer_migrate_page,
 	.is_partially_uptodate  = block_is_partially_uptodate,
+	.error_remove_page	= generic_error_remove_page,
 };
 
 static const struct address_space_operations ext4_writeback_aops = {
@@ -3401,6 +3846,7 @@ static const struct address_space_operations ext4_writeback_aops = {
 	.direct_IO		= ext4_direct_IO,
 	.migratepage		= buffer_migrate_page,
 	.is_partially_uptodate  = block_is_partially_uptodate,
+	.error_remove_page	= generic_error_remove_page,
 };
 
 static const struct address_space_operations ext4_journalled_aops = {
@@ -3415,6 +3861,7 @@ static const struct address_space_operations ext4_journalled_aops = {
 	.invalidatepage		= ext4_invalidatepage,
 	.releasepage		= ext4_releasepage,
 	.is_partially_uptodate  = block_is_partially_uptodate,
+	.error_remove_page	= generic_error_remove_page,
 };
 
 static const struct address_space_operations ext4_da_aops = {
@@ -3431,6 +3878,7 @@ static const struct address_space_operations ext4_da_aops = {
 	.direct_IO		= ext4_direct_IO,
 	.migratepage		= buffer_migrate_page,
 	.is_partially_uptodate  = block_is_partially_uptodate,
+	.error_remove_page	= generic_error_remove_page,
 };
 
 void ext4_set_aops(struct inode *inode)
@@ -4547,8 +4995,7 @@ static int ext4_inode_blocks_set(handle_t *handle,
  */
 static int ext4_do_update_inode(handle_t *handle,
 				struct inode *inode,
-				struct ext4_iloc *iloc,
-				int do_sync)
+				struct ext4_iloc *iloc)
 {
 	struct ext4_inode *raw_inode = ext4_raw_inode(iloc);
 	struct ext4_inode_info *ei = EXT4_I(inode);
@@ -4649,22 +5096,10 @@ static int ext4_do_update_inode(handle_t *handle,
 		raw_inode->i_extra_isize = cpu_to_le16(ei->i_extra_isize);
 	}
 
-	/*
-	 * If we're not using a journal and we were called from
-	 * ext4_write_inode() to sync the inode (making do_sync true),
-	 * we can just use sync_dirty_buffer() directly to do our dirty
-	 * work.  Testing s_journal here is a bit redundant but it's
-	 * worth it to avoid potential future trouble.
-	 */
-	if (EXT4_SB(inode->i_sb)->s_journal == NULL && do_sync) {
-		BUFFER_TRACE(bh, "call sync_dirty_buffer");
-		sync_dirty_buffer(bh);
-	} else {
-		BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
-		rc = ext4_handle_dirty_metadata(handle, inode, bh);
-		if (!err)
-			err = rc;
-	}
+	BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata");
+	rc = ext4_handle_dirty_metadata(handle, inode, bh);
+	if (!err)
+		err = rc;
 	ei->i_state &= ~EXT4_STATE_NEW;
 
 out_brelse:
@@ -4732,8 +5167,16 @@ int ext4_write_inode(struct inode *inode, int wait)
 		err = ext4_get_inode_loc(inode, &iloc);
 		if (err)
 			return err;
-		err = ext4_do_update_inode(EXT4_NOJOURNAL_HANDLE,
-					   inode, &iloc, wait);
+		if (wait)
+			sync_dirty_buffer(iloc.bh);
+		if (buffer_req(iloc.bh) && !buffer_uptodate(iloc.bh)) {
+			ext4_error(inode->i_sb, __func__,
+				   "IO error syncing inode, "
+				   "inode=%lu, block=%llu",
+				   inode->i_ino,
+				   (unsigned long long)iloc.bh->b_blocknr);
+			err = -EIO;
+		}
 	}
 	return err;
 }
@@ -5029,7 +5472,7 @@ int ext4_mark_iloc_dirty(handle_t *handle,
 	get_bh(iloc->bh);
 
 	/* ext4_do_update_inode() does jbd2_journal_dirty_metadata */
-	err = ext4_do_update_inode(handle, inode, iloc, 0);
+	err = ext4_do_update_inode(handle, inode, iloc);
 	put_bh(iloc->bh);
 	return err;
 }
@@ -5173,27 +5616,14 @@ int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode)
  */
 void ext4_dirty_inode(struct inode *inode)
 {
-	handle_t *current_handle = ext4_journal_current_handle();
 	handle_t *handle;
 
-	if (!ext4_handle_valid(current_handle)) {
-		ext4_mark_inode_dirty(current_handle, inode);
-		return;
-	}
-
 	handle = ext4_journal_start(inode, 2);
 	if (IS_ERR(handle))
 		goto out;
-	if (current_handle &&
-		current_handle->h_transaction != handle->h_transaction) {
-		/* This task has a transaction open against a different fs */
-		printk(KERN_EMERG "%s: transactions do not match!\n",
-		       __func__);
-	} else {
-		jbd_debug(5, "marking dirty.  outer handle=%p\n",
-				current_handle);
-		ext4_mark_inode_dirty(handle, inode);
-	}
+
+	ext4_mark_inode_dirty(handle, inode);
+
 	ext4_journal_stop(handle);
 out:
 	return;
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index e9c6189..bba1282 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -2096,207 +2096,6 @@ out:
 	return err;
 }
 
-#ifdef EXT4_MB_HISTORY
-struct ext4_mb_proc_session {
-	struct ext4_mb_history *history;
-	struct super_block *sb;
-	int start;
-	int max;
-};
-
-static void *ext4_mb_history_skip_empty(struct ext4_mb_proc_session *s,
-					struct ext4_mb_history *hs,
-					int first)
-{
-	if (hs == s->history + s->max)
-		hs = s->history;
-	if (!first && hs == s->history + s->start)
-		return NULL;
-	while (hs->orig.fe_len == 0) {
-		hs++;
-		if (hs == s->history + s->max)
-			hs = s->history;
-		if (hs == s->history + s->start)
-			return NULL;
-	}
-	return hs;
-}
-
-static void *ext4_mb_seq_history_start(struct seq_file *seq, loff_t *pos)
-{
-	struct ext4_mb_proc_session *s = seq->private;
-	struct ext4_mb_history *hs;
-	int l = *pos;
-
-	if (l == 0)
-		return SEQ_START_TOKEN;
-	hs = ext4_mb_history_skip_empty(s, s->history + s->start, 1);
-	if (!hs)
-		return NULL;
-	while (--l && (hs = ext4_mb_history_skip_empty(s, ++hs, 0)) != NULL);
-	return hs;
-}
-
-static void *ext4_mb_seq_history_next(struct seq_file *seq, void *v,
-				      loff_t *pos)
-{
-	struct ext4_mb_proc_session *s = seq->private;
-	struct ext4_mb_history *hs = v;
-
-	++*pos;
-	if (v == SEQ_START_TOKEN)
-		return ext4_mb_history_skip_empty(s, s->history + s->start, 1);
-	else
-		return ext4_mb_history_skip_empty(s, ++hs, 0);
-}
-
-static int ext4_mb_seq_history_show(struct seq_file *seq, void *v)
-{
-	char buf[25], buf2[25], buf3[25], *fmt;
-	struct ext4_mb_history *hs = v;
-
-	if (v == SEQ_START_TOKEN) {
-		seq_printf(seq, "%-5s %-8s %-23s %-23s %-23s %-5s "
-				"%-5s %-2s %-6s %-5s %-5s %-6s\n",
-			  "pid", "inode", "original", "goal", "result", "found",
-			   "grps", "cr", "flags", "merge", "tail", "broken");
-		return 0;
-	}
-
-	if (hs->op == EXT4_MB_HISTORY_ALLOC) {
-		fmt = "%-5u %-8u %-23s %-23s %-23s %-5u %-5u %-2u "
-			"0x%04x %-5s %-5u %-6u\n";
-		sprintf(buf2, "%u/%d/%u@%u", hs->result.fe_group,
-			hs->result.fe_start, hs->result.fe_len,
-			hs->result.fe_logical);
-		sprintf(buf, "%u/%d/%u@%u", hs->orig.fe_group,
-			hs->orig.fe_start, hs->orig.fe_len,
-			hs->orig.fe_logical);
-		sprintf(buf3, "%u/%d/%u@%u", hs->goal.fe_group,
-			hs->goal.fe_start, hs->goal.fe_len,
-			hs->goal.fe_logical);
-		seq_printf(seq, fmt, hs->pid, hs->ino, buf, buf3, buf2,
-				hs->found, hs->groups, hs->cr, hs->flags,
-				hs->merged ? "M" : "", hs->tail,
-				hs->buddy ? 1 << hs->buddy : 0);
-	} else if (hs->op == EXT4_MB_HISTORY_PREALLOC) {
-		fmt = "%-5u %-8u %-23s %-23s %-23s\n";
-		sprintf(buf2, "%u/%d/%u@%u", hs->result.fe_group,
-			hs->result.fe_start, hs->result.fe_len,
-			hs->result.fe_logical);
-		sprintf(buf, "%u/%d/%u@%u", hs->orig.fe_group,
-			hs->orig.fe_start, hs->orig.fe_len,
-			hs->orig.fe_logical);
-		seq_printf(seq, fmt, hs->pid, hs->ino, buf, "", buf2);
-	} else if (hs->op == EXT4_MB_HISTORY_DISCARD) {
-		sprintf(buf2, "%u/%d/%u", hs->result.fe_group,
-			hs->result.fe_start, hs->result.fe_len);
-		seq_printf(seq, "%-5u %-8u %-23s discard\n",
-				hs->pid, hs->ino, buf2);
-	} else if (hs->op == EXT4_MB_HISTORY_FREE) {
-		sprintf(buf2, "%u/%d/%u", hs->result.fe_group,
-			hs->result.fe_start, hs->result.fe_len);
-		seq_printf(seq, "%-5u %-8u %-23s free\n",
-				hs->pid, hs->ino, buf2);
-	}
-	return 0;
-}
-
-static void ext4_mb_seq_history_stop(struct seq_file *seq, void *v)
-{
-}
-
-static const struct seq_operations ext4_mb_seq_history_ops = {
-	.start  = ext4_mb_seq_history_start,
-	.next   = ext4_mb_seq_history_next,
-	.stop   = ext4_mb_seq_history_stop,
-	.show   = ext4_mb_seq_history_show,
-};
-
-static int ext4_mb_seq_history_open(struct inode *inode, struct file *file)
-{
-	struct super_block *sb = PDE(inode)->data;
-	struct ext4_sb_info *sbi = EXT4_SB(sb);
-	struct ext4_mb_proc_session *s;
-	int rc;
-	int size;
-
-	if (unlikely(sbi->s_mb_history == NULL))
-		return -ENOMEM;
-	s = kmalloc(sizeof(*s), GFP_KERNEL);
-	if (s == NULL)
-		return -ENOMEM;
-	s->sb = sb;
-	size = sizeof(struct ext4_mb_history) * sbi->s_mb_history_max;
-	s->history = kmalloc(size, GFP_KERNEL);
-	if (s->history == NULL) {
-		kfree(s);
-		return -ENOMEM;
-	}
-
-	spin_lock(&sbi->s_mb_history_lock);
-	memcpy(s->history, sbi->s_mb_history, size);
-	s->max = sbi->s_mb_history_max;
-	s->start = sbi->s_mb_history_cur % s->max;
-	spin_unlock(&sbi->s_mb_history_lock);
-
-	rc = seq_open(file, &ext4_mb_seq_history_ops);
-	if (rc == 0) {
-		struct seq_file *m = (struct seq_file *)file->private_data;
-		m->private = s;
-	} else {
-		kfree(s->history);
-		kfree(s);
-	}
-	return rc;
-
-}
-
-static int ext4_mb_seq_history_release(struct inode *inode, struct file *file)
-{
-	struct seq_file *seq = (struct seq_file *)file->private_data;
-	struct ext4_mb_proc_session *s = seq->private;
-	kfree(s->history);
-	kfree(s);
-	return seq_release(inode, file);
-}
-
-static ssize_t ext4_mb_seq_history_write(struct file *file,
-				const char __user *buffer,
-				size_t count, loff_t *ppos)
-{
-	struct seq_file *seq = (struct seq_file *)file->private_data;
-	struct ext4_mb_proc_session *s = seq->private;
-	struct super_block *sb = s->sb;
-	char str[32];
-	int value;
-
-	if (count >= sizeof(str)) {
-		printk(KERN_ERR "EXT4-fs: %s string too long, max %u bytes\n",
-				"mb_history", (int)sizeof(str));
-		return -EOVERFLOW;
-	}
-
-	if (copy_from_user(str, buffer, count))
-		return -EFAULT;
-
-	value = simple_strtol(str, NULL, 0);
-	if (value < 0)
-		return -ERANGE;
-	EXT4_SB(sb)->s_mb_history_filter = value;
-
-	return count;
-}
-
-static const struct file_operations ext4_mb_seq_history_fops = {
-	.owner		= THIS_MODULE,
-	.open		= ext4_mb_seq_history_open,
-	.read		= seq_read,
-	.write		= ext4_mb_seq_history_write,
-	.llseek		= seq_lseek,
-	.release	= ext4_mb_seq_history_release,
-};
-
 static void *ext4_mb_seq_groups_start(struct seq_file *seq, loff_t *pos)
 {
 	struct super_block *sb = seq->private;
@@ -2396,82 +2195,6 @@ static const struct file_operations ext4_mb_seq_groups_fops = {
 	.release	= seq_release,
 };
 
-static void ext4_mb_history_release(struct super_block *sb)
-{
-	struct ext4_sb_info *sbi = EXT4_SB(sb);
-
-	if (sbi->s_proc != NULL) {
-		remove_proc_entry("mb_groups", sbi->s_proc);
-		if (sbi->s_mb_history_max)
-			remove_proc_entry("mb_history", sbi->s_proc);
-	}
-	kfree(sbi->s_mb_history);
-}
-
-static void ext4_mb_history_init(struct super_block *sb)
-{
-	struct ext4_sb_info *sbi = EXT4_SB(sb);
-	int i;
-
-	if (sbi->s_proc != NULL) {
-		if (sbi->s_mb_history_max)
-			proc_create_data("mb_history", S_IRUGO, sbi->s_proc,
-					 &ext4_mb_seq_history_fops, sb);
-		proc_create_data("mb_groups", S_IRUGO, sbi->s_proc,
-				 &ext4_mb_seq_groups_fops, sb);
-	}
-
-	sbi->s_mb_history_cur = 0;
-	spin_lock_init(&sbi->s_mb_history_lock);
-	i = sbi->s_mb_history_max * sizeof(struct ext4_mb_history);
-	sbi->s_mb_history = i ? kzalloc(i, GFP_KERNEL) : NULL;
-	/* if we can't allocate history, then we simple won't use it */
-}
-
-static noinline_for_stack void
-ext4_mb_store_history(struct ext4_allocation_context *ac)
-{
-	struct ext4_sb_info *sbi = EXT4_SB(ac->ac_sb);
-	struct ext4_mb_history h;
-
-	if (sbi->s_mb_history == NULL)
-		return;
-
-	if (!(ac->ac_op & sbi->s_mb_history_filter))
-		return;
-
-	h.op = ac->ac_op;
-	h.pid = current->pid;
-	h.ino = ac->ac_inode ? ac->ac_inode->i_ino : 0;
-	h.orig = ac->ac_o_ex;
-	h.result = ac->ac_b_ex;
-	h.flags = ac->ac_flags;
-	h.found = ac->ac_found;
-	h.groups = ac->ac_groups_scanned;
-	h.cr = ac->ac_criteria;
-	h.tail = ac->ac_tail;
-	h.buddy = ac->ac_buddy;
-	h.merged = 0;
-	if (ac->ac_op == EXT4_MB_HISTORY_ALLOC) {
-		if (ac->ac_g_ex.fe_start == ac->ac_b_ex.fe_start &&
-				ac->ac_g_ex.fe_group == ac->ac_b_ex.fe_group)
-			h.merged = 1;
-		h.goal = ac->ac_g_ex;
-		h.result = ac->ac_f_ex;
-	}
-
-	spin_lock(&sbi->s_mb_history_lock);
-	memcpy(sbi->s_mb_history + sbi->s_mb_history_cur, &h, sizeof(h));
-	if (++sbi->s_mb_history_cur >= sbi->s_mb_history_max)
-		sbi->s_mb_history_cur = 0;
-	spin_unlock(&sbi->s_mb_history_lock);
-}
-
-#else
-#define ext4_mb_history_release(sb)
-#define ext4_mb_history_init(sb)
-#endif
-
 
 /* Create and initialize ext4_group_info data for the given group. */
 int ext4_mb_add_groupinfo(struct super_block *sb, ext4_group_t group,
@@ -2690,7 +2413,6 @@ int ext4_mb_init(struct super_block *sb, int needs_recovery)
 	sbi->s_mb_stats = MB_DEFAULT_STATS;
 	sbi->s_mb_stream_request = MB_DEFAULT_STREAM_THRESHOLD;
 	sbi->s_mb_order2_reqs = MB_DEFAULT_ORDER2_REQS;
-	sbi->s_mb_history_filter = EXT4_MB_HISTORY_DEFAULT;
 	sbi->s_mb_group_prealloc = MB_DEFAULT_GROUP_PREALLOC;
 
 	sbi->s_locality_groups = alloc_percpu(struct ext4_locality_group);
@@ -2708,12 +2430,12 @@ int ext4_mb_init(struct super_block *sb, int needs_recovery)
 		spin_lock_init(&lg->lg_prealloc_lock);
 	}
 
-	ext4_mb_history_init(sb);
+	if (sbi->s_proc)
+		proc_create_data("mb_groups", S_IRUGO, sbi->s_proc,
+				 &ext4_mb_seq_groups_fops, sb);
 
 	if (sbi->s_journal)
 		sbi->s_journal->j_commit_callback = release_blocks_on_commit;
-
-	printk(KERN_INFO "EXT4-fs: mballoc enabled\n");
 	return 0;
 }
 
@@ -2790,7 +2512,8 @@ int ext4_mb_release(struct super_block *sb)
 	}
 
 	free_percpu(sbi->s_locality_groups);
-	ext4_mb_history_release(sb);
+	if (sbi->s_proc)
+		remove_proc_entry("mb_groups", sbi->s_proc);
 
 	return 0;
 }
@@ -3276,7 +2999,10 @@ static void ext4_mb_collect_stats(struct ext4_allocation_context *ac)
 			atomic_inc(&sbi->s_bal_breaks);
 	}
 
-	ext4_mb_store_history(ac);
+	if (ac->ac_op == EXT4_MB_HISTORY_ALLOC)
+		trace_ext4_mballoc_alloc(ac);
+	else
+		trace_ext4_mballoc_prealloc(ac);
 }
 
 /*
@@ -3776,7 +3502,6 @@ ext4_mb_release_inode_pa(struct ext4_buddy *e4b, struct buffer_head *bitmap_bh,
 	if (ac) {
 		ac->ac_sb = sb;
 		ac->ac_inode = pa->pa_inode;
-		ac->ac_op = EXT4_MB_HISTORY_DISCARD;
 	}
 
 	while (bit < end) {
@@ -3796,7 +3521,7 @@ ext4_mb_release_inode_pa(struct ext4_buddy *e4b, struct buffer_head *bitmap_bh,
 			ac->ac_b_ex.fe_start = bit;
 			ac->ac_b_ex.fe_len = next - bit;
 			ac->ac_b_ex.fe_logical = 0;
-			ext4_mb_store_history(ac);
+			trace_ext4_mballoc_discard(ac);
 		}
 
 		trace_ext4_mb_release_inode_pa(ac, pa, grp_blk_start + bit,
@@ -3831,9 +3556,6 @@ ext4_mb_release_group_pa(struct ext4_buddy *e4b,
 	ext4_group_t group;
 	ext4_grpblk_t bit;
 
-	if (ac)
-		ac->ac_op = EXT4_MB_HISTORY_DISCARD;
-
 	trace_ext4_mb_release_group_pa(ac, pa);
 	BUG_ON(pa->pa_deleted == 0);
 	ext4_get_group_no_and_offset(sb, pa->pa_pstart, &group, &bit);
@@ -3848,7 +3570,7 @@ ext4_mb_release_group_pa(struct ext4_buddy *e4b,
 		ac->ac_b_ex.fe_start = bit;
 		ac->ac_b_ex.fe_len = pa->pa_len;
 		ac->ac_b_ex.fe_logical = 0;
-		ext4_mb_store_history(ac);
+		trace_ext4_mballoc_discard(ac);
 	}
 
 	return 0;
@@ -4189,7 +3911,6 @@ static void ext4_mb_group_or_file(struct ext4_allocation_context *ac)
 	size = ac->ac_o_ex.fe_logical + ac->ac_o_ex.fe_len;
 	isize = (i_size_read(ac->ac_inode) + ac->ac_sb->s_blocksize - 1)
 		>> bsbits;
-	size = max(size, isize);
 
 	if ((size == isize) &&
 	    !ext4_fs_is_busy(sbi) &&
@@ -4199,6 +3920,7 @@ static void ext4_mb_group_or_file(struct ext4_allocation_context *ac)
 	}
 
 	/* don't use group allocation for large files */
+	size = max(size, isize);
 	if (size >= sbi->s_mb_stream_request) {
 		ac->ac_flags |= EXT4_MB_STREAM_ALLOC;
 		return;
@@ -4739,7 +4461,6 @@ void ext4_mb_free_blocks(handle_t *handle, struct inode *inode,
 
 	ac = kmem_cache_alloc(ext4_ac_cachep, GFP_NOFS);
 	if (ac) {
-		ac->ac_op = EXT4_MB_HISTORY_FREE;
 		ac->ac_inode = inode;
 		ac->ac_sb = sb;
 	}
@@ -4806,7 +4527,7 @@ do_more:
 		ac->ac_b_ex.fe_group = block_group;
 		ac->ac_b_ex.fe_start = bit;
 		ac->ac_b_ex.fe_len = count;
-		ext4_mb_store_history(ac);
+		trace_ext4_mballoc_free(ac);
 	}
 
 	err = ext4_mb_load_buddy(sb, block_group, &e4b);
diff --git a/fs/ext4/mballoc.h b/fs/ext4/mballoc.h
index 188d3d7..0ca8110 100644
--- a/fs/ext4/mballoc.h
+++ b/fs/ext4/mballoc.h
@@ -52,18 +52,8 @@ extern u8 mb_enable_debug;
 #define mb_debug(n, fmt, a...)
 #endif
 
-/*
- * with EXT4_MB_HISTORY mballoc stores last N allocations in memory
- * and you can monitor it in /proc/fs/ext4/<dev>/mb_history
- */
-#define EXT4_MB_HISTORY
 #define EXT4_MB_HISTORY_ALLOC		1	/* allocation */
 #define EXT4_MB_HISTORY_PREALLOC	2	/* preallocated blocks used */
-#define EXT4_MB_HISTORY_DISCARD		4	/* preallocation discarded */
-#define EXT4_MB_HISTORY_FREE		8	/* free */
-
-#define EXT4_MB_HISTORY_DEFAULT		(EXT4_MB_HISTORY_ALLOC | \
-					 EXT4_MB_HISTORY_PREALLOC)
 
 /*
  * How long mballoc can look for a best extent (in found extents)
@@ -84,7 +74,7 @@ extern u8 mb_enable_debug;
  * with 'ext4_mb_stats' allocator will collect stats that will be
  * shown at umount. The collecting costs though!
  */
-#define MB_DEFAULT_STATS		1
+#define MB_DEFAULT_STATS		0
 
 /*
  * files smaller than MB_DEFAULT_STREAM_THRESHOLD are served
@@ -217,22 +207,6 @@ struct ext4_allocation_context {
 #define AC_STATUS_FOUND		2
 #define AC_STATUS_BREAK		3
 
-struct ext4_mb_history {
-	struct ext4_free_extent orig;	/* orig allocation */
-	struct ext4_free_extent goal;	/* goal allocation */
-	struct ext4_free_extent result;	/* result allocation */
-	unsigned pid;
-	unsigned ino;
-	__u16 found;	/* how many extents have been found */
-	__u16 groups;	/* how many groups have been scanned */
-	__u16 tail;	/* what tail broke some buddy */
-	__u16 buddy;	/* buddy the tail ^^^ broke */
-	__u16 flags;
-	__u8 cr:3;	/* which phase the result extent was found at */
-	__u8 op:4;
-	__u8 merged:1;
-};
-
 struct ext4_buddy {
 	struct page *bd_buddy_page;
 	void *bd_buddy;
@@ -247,13 +221,6 @@ struct ext4_buddy {
 #define EXT4_MB_BITMAP(e4b)	((e4b)->bd_bitmap)
 #define EXT4_MB_BUDDY(e4b)	((e4b)->bd_buddy)
 
-#ifndef EXT4_MB_HISTORY
-static inline void ext4_mb_store_history(struct ext4_allocation_context *ac)
-{
-	return;
-}
-#endif
-
 #define in_range(b, first, len)	((b) >= (first) && (b) <= (first) + (len) - 1)
 
 static inline ext4_fsblk_t ext4_grp_offs_to_block(struct super_block *sb,
diff --git a/fs/ext4/migrate.c b/fs/ext4/migrate.c
index bf519f2..a93d5b8 100644
--- a/fs/ext4/migrate.c
+++ b/fs/ext4/migrate.c
@@ -75,7 +75,7 @@ static int finish_range(handle_t *handle, struct inode *inode,
 				goto err_out;
 		}
 	}
-	retval = ext4_ext_insert_extent(handle, inode, path, &newext);
+	retval = ext4_ext_insert_extent(handle, inode, path, &newext, 0);
 err_out:
 	if (path) {
 		ext4_ext_drop_refs(path);
diff --git a/fs/ext4/move_extent.c b/fs/ext4/move_extent.c
index c07a291..25b6b14 100644
--- a/fs/ext4/move_extent.c
+++ b/fs/ext4/move_extent.c
@@ -322,7 +322,7 @@ mext_insert_across_blocks(handle_t *handle, struct inode *orig_inode,
 			goto out;
 
 		if (ext4_ext_insert_extent(handle, orig_inode,
-					orig_path, new_ext))
+					orig_path, new_ext, 0))
 			goto out;
 	}
 
@@ -333,7 +333,7 @@ mext_insert_across_blocks(handle_t *handle, struct inode *orig_inode,
 			goto out;
 
 		if (ext4_ext_insert_extent(handle, orig_inode,
-					   orig_path, end_ext))
+					   orig_path, end_ext, 0))
 			goto out;
 	}
 out:
@@ -1001,14 +1001,6 @@ mext_check_arguments(struct inode *orig_inode,
 		return -EINVAL;
 	}
 
-	/* orig and donor should be different file */
-	if (orig_inode->i_ino == donor_inode->i_ino) {
-		ext4_debug("ext4 move extent: The argument files should not "
-			"be same file [ino:orig %lu, donor %lu]\n",
-			orig_inode->i_ino, donor_inode->i_ino);
-		return -EINVAL;
-	}
-
 	/* Ext4 move extent supports only extent based file */
 	if (!(EXT4_I(orig_inode)->i_flags & EXT4_EXTENTS_FL)) {
 		ext4_debug("ext4 move extent: orig file is not extents "
@@ -1232,6 +1224,14 @@ ext4_move_extents(struct file *o_filp, struct file *d_filp,
 	int block_len_in_page;
 	int uninit;
 
+	/* orig and donor should be different file */
+	if (orig_inode->i_ino == donor_inode->i_ino) {
+		ext4_debug("ext4 move extent: The argument files should not "
+			"be same file [ino:orig %lu, donor %lu]\n",
+			orig_inode->i_ino, donor_inode->i_ino);
+		return -EINVAL;
+	}
+
 	/* protect orig and donor against a truncate */
 	ret1 = mext_inode_double_lock(orig_inode, donor_inode);
 	if (ret1 < 0)
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 42f81d2..7c8fe80 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -2076,7 +2076,8 @@ int ext4_orphan_del(handle_t *handle, struct inode *inode)
 	struct ext4_iloc iloc;
 	int err = 0;
 
-	if (!ext4_handle_valid(handle))
+	/* ext4_handle_valid() assumes a valid handle_t pointer */
+	if (handle && !ext4_handle_valid(handle))
 		return 0;
 
 	mutex_lock(&EXT4_SB(inode->i_sb)->s_orphan_lock);
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index df539ba..312211e 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -50,13 +50,6 @@
 #define CREATE_TRACE_POINTS
 #include <trace/events/ext4.h>
 
-static int default_mb_history_length = 1000;
-
-module_param_named(default_mb_history_length, default_mb_history_length,
-		   int, 0644);
-MODULE_PARM_DESC(default_mb_history_length,
-		 "Default number of entries saved for mb_history");
-
 struct proc_dir_entry *ext4_proc_root;
 static struct kset *ext4_kset;
 
@@ -189,6 +182,36 @@ void ext4_itable_unused_set(struct super_block *sb,
 		bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 }
 
+
+/* Just increment the non-pointer handle value */
+static handle_t *ext4_get_nojournal(void)
+{
+	handle_t *handle = current->journal_info;
+	unsigned long ref_cnt = (unsigned long)handle;
+
+	BUG_ON(ref_cnt >= EXT4_NOJOURNAL_MAX_REF_COUNT);
+
+	ref_cnt++;
+	handle = (handle_t *)ref_cnt;
+
+	current->journal_info = handle;
+	return handle;
+}
+
+
+/* Decrement the non-pointer handle value */
+static void ext4_put_nojournal(handle_t *handle)
+{
+	unsigned long ref_cnt = (unsigned long)handle;
+
+	BUG_ON(ref_cnt == 0);
+
+	ref_cnt--;
+	handle = (handle_t *)ref_cnt;
+
+	current->journal_info = handle;
+}
+
 /*
  * Wrappers for jbd2_journal_start/end.
  *
@@ -215,11 +238,7 @@ handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
 		}
 		return jbd2_journal_start(journal, nblocks);
 	}
-	/*
-	 * We're not journaling, return the appropriate indication.
-	 */
-	current->journal_info = EXT4_NOJOURNAL_HANDLE;
-	return current->journal_info;
+	return ext4_get_nojournal();
 }
 
 /*
@@ -235,11 +254,7 @@ int __ext4_journal_stop(const char *where, handle_t *handle)
 	int rc;
 
 	if (!ext4_handle_valid(handle)) {
-		/*
-		 * Do this here since we don't call jbd2_journal_stop() in
-		 * no-journal mode.
-		 */
-		current->journal_info = NULL;
+		ext4_put_nojournal(handle);
 		return 0;
 	}
 	sb = handle->h_transaction->t_journal->j_private;
@@ -580,6 +595,9 @@ static void ext4_put_super(struct super_block *sb)
 	struct ext4_super_block *es = sbi->s_es;
 	int i, err;
 
+	flush_workqueue(sbi->dio_unwritten_wq);
+	destroy_workqueue(sbi->dio_unwritten_wq);
+
 	lock_super(sb);
 	lock_kernel();
 	if (sb->s_dirt)
@@ -684,6 +702,8 @@ static struct inode *ext4_alloc_inode(struct super_block *sb)
 	ei->i_allocated_meta_blocks = 0;
 	ei->i_delalloc_reserved_flag = 0;
 	spin_lock_init(&(ei->i_block_reservation_lock));
+	INIT_LIST_HEAD(&ei->i_aio_dio_complete_list);
+	ei->cur_aio_dio = NULL;
 
 	return &ei->vfs_inode;
 }
@@ -1052,7 +1072,7 @@ enum {
 	Opt_journal_update, Opt_journal_dev,
 	Opt_journal_checksum, Opt_journal_async_commit,
 	Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
-	Opt_data_err_abort, Opt_data_err_ignore, Opt_mb_history_length,
+	Opt_data_err_abort, Opt_data_err_ignore,
 	Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
 	Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_quota, Opt_noquota,
 	Opt_ignore, Opt_barrier, Opt_nobarrier, Opt_err, Opt_resize,
@@ -1099,7 +1119,6 @@ static const match_table_t tokens = {
 	{Opt_data_writeback, "data=writeback"},
 	{Opt_data_err_abort, "data_err=abort"},
 	{Opt_data_err_ignore, "data_err=ignore"},
-	{Opt_mb_history_length, "mb_history_length=%u"},
 	{Opt_offusrjquota, "usrjquota="},
 	{Opt_usrjquota, "usrjquota=%s"},
 	{Opt_offgrpjquota, "grpjquota="},
@@ -1340,13 +1359,6 @@ static int parse_options(char *options, struct super_block *sb,
 		case Opt_data_err_ignore:
 			clear_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
 			break;
-		case Opt_mb_history_length:
-			if (match_int(&args[0], &option))
-				return 0;
-			if (option < 0)
-				return 0;
-			sbi->s_mb_history_max = option;
-			break;
 #ifdef CONFIG_QUOTA
 		case Opt_usrjquota:
 			qtype = USRQUOTA;
@@ -1646,13 +1658,6 @@ static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
 			EXT4_INODES_PER_GROUP(sb),
 			sbi->s_mount_opt);
 
-	if (EXT4_SB(sb)->s_journal) {
-		ext4_msg(sb, KERN_INFO, "%s journal on %s",
-		       EXT4_SB(sb)->s_journal->j_inode ? "internal" :
-		       "external", EXT4_SB(sb)->s_journal->j_devname);
-	} else {
-		ext4_msg(sb, KERN_INFO, "no journal");
-	}
 	return res;
 }
 
@@ -2197,6 +2202,7 @@ EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
+EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
 
 static struct attribute *ext4_attrs[] = {
 	ATTR_LIST(delayed_allocation_blocks),
@@ -2210,6 +2216,7 @@ static struct attribute *ext4_attrs[] = {
 	ATTR_LIST(mb_order2_req),
 	ATTR_LIST(mb_stream_req),
 	ATTR_LIST(mb_group_prealloc),
+	ATTR_LIST(max_writeback_mb_bump),
 	NULL,
 };
 
@@ -2413,7 +2420,6 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
 	sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
 	sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
 	sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
-	sbi->s_mb_history_max = default_mb_history_length;
 
 	set_opt(sbi->s_mount_opt, BARRIER);
 
@@ -2679,6 +2685,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
 	}
 
 	sbi->s_stripe = ext4_get_stripe_size(sbi);
+	sbi->s_max_writeback_mb_bump = 128;
 
 	/*
 	 * set up enough so that it can read an inode
@@ -2798,6 +2805,12 @@ no_journal:
 			clear_opt(sbi->s_mount_opt, NOBH);
 		}
 	}
+	EXT4_SB(sb)->dio_unwritten_wq = create_workqueue("ext4-dio-unwritten");
+	if (!EXT4_SB(sb)->dio_unwritten_wq) {
+		printk(KERN_ERR "EXT4-fs: failed to create DIO workqueue\n");
+		goto failed_mount_wq;
+	}
+
 	/*
 	 * The jbd2_journal_load will have done any necessary log recovery,
 	 * so we can safely mount the rest of the filesystem now.
@@ -2849,12 +2862,12 @@ no_journal:
 			 "available");
 	}
 
-	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
+	if (test_opt(sb, DELALLOC) &&
+	    (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)) {
 		ext4_msg(sb, KERN_WARNING, "Ignoring delalloc option - "
 			 "requested data journaling mode");
 		clear_opt(sbi->s_mount_opt, DELALLOC);
-	} else if (test_opt(sb, DELALLOC))
-		ext4_msg(sb, KERN_INFO, "delayed allocation enabled");
+	}
 
 	err = ext4_setup_system_zone(sb);
 	if (err) {
@@ -2910,6 +2923,8 @@ cantfind_ext4:
 
 failed_mount4:
 	ext4_msg(sb, KERN_ERR, "mount failed");
+	destroy_workqueue(EXT4_SB(sb)->dio_unwritten_wq);
+failed_mount_wq:
 	ext4_release_system_zone(sb);
 	if (sbi->s_journal) {
 		jbd2_journal_destroy(sbi->s_journal);
@@ -3164,9 +3179,7 @@ static int ext4_load_journal(struct super_block *sb,
 			return -EINVAL;
 	}
 
-	if (journal->j_flags & JBD2_BARRIER)
-		ext4_msg(sb, KERN_INFO, "barriers enabled");
-	else
+	if (!(journal->j_flags & JBD2_BARRIER))
 		ext4_msg(sb, KERN_INFO, "barriers disabled");
 
 	if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
@@ -3361,11 +3374,13 @@ static int ext4_sync_fs(struct super_block *sb, int wait)
 {
 	int ret = 0;
 	tid_t target;
+	struct ext4_sb_info *sbi = EXT4_SB(sb);
 
 	trace_ext4_sync_fs(sb, wait);
-	if (jbd2_journal_start_commit(EXT4_SB(sb)->s_journal, &target)) {
+	flush_workqueue(sbi->dio_unwritten_wq);
+	if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
 		if (wait)
-			jbd2_log_wait_commit(EXT4_SB(sb)->s_journal, target);
+			jbd2_log_wait_commit(sbi->s_journal, target);
 	}
 	return ret;
 }
@@ -3951,27 +3966,6 @@ static struct file_system_type ext4_fs_type = {
 	.fs_flags	= FS_REQUIRES_DEV,
 };
 
-#ifdef CONFIG_EXT4DEV_COMPAT
-static int ext4dev_get_sb(struct file_system_type *fs_type, int flags,
-			  const char *dev_name, void *data,struct vfsmount *mnt)
-{
-	printk(KERN_WARNING "EXT4-fs (%s): Update your userspace programs "
-	       "to mount using ext4\n", dev_name);
-	printk(KERN_WARNING "EXT4-fs (%s): ext4dev backwards compatibility "
-	       "will go away by 2.6.31\n", dev_name);
-	return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super,mnt);
-}
-
-static struct file_system_type ext4dev_fs_type = {
-	.owner		= THIS_MODULE,
-	.name		= "ext4dev",
-	.get_sb		= ext4dev_get_sb,
-	.kill_sb	= kill_block_super,
-	.fs_flags	= FS_REQUIRES_DEV,
-};
-MODULE_ALIAS("ext4dev");
-#endif
-
 static int __init init_ext4_fs(void)
 {
 	int err;
@@ -3996,13 +3990,6 @@ static int __init init_ext4_fs(void)
 	err = register_filesystem(&ext4_fs_type);
 	if (err)
 		goto out;
-#ifdef CONFIG_EXT4DEV_COMPAT
-	err = register_filesystem(&ext4dev_fs_type);
-	if (err) {
-		unregister_filesystem(&ext4_fs_type);
-		goto out;
-	}
-#endif
 	return 0;
 out:
 	destroy_inodecache();
@@ -4021,9 +4008,6 @@ out4:
 static void __exit exit_ext4_fs(void)
 {
 	unregister_filesystem(&ext4_fs_type);
-#ifdef CONFIG_EXT4DEV_COMPAT
-	unregister_filesystem(&ext4dev_fs_type);
-#endif
 	destroy_inodecache();
 	exit_ext4_xattr();
 	exit_ext4_mballoc();
diff --git a/fs/fat/fat.h b/fs/fat/fat.h
index adb0e72..7db0979 100644
--- a/fs/fat/fat.h
+++ b/fs/fat/fat.h
@@ -323,7 +323,7 @@ extern int fat_flush_inodes(struct super_block *sb, struct inode *i1,
 /* fat/misc.c */
 extern void fat_fs_error(struct super_block *s, const char *fmt, ...)
 	__attribute__ ((format (printf, 2, 3))) __cold;
-extern void fat_clusters_flush(struct super_block *sb);
+extern int fat_clusters_flush(struct super_block *sb);
 extern int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster);
 extern void fat_time_fat2unix(struct msdos_sb_info *sbi, struct timespec *ts,
 			      __le16 __time, __le16 __date, u8 time_cs);
diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index 8970d8c..76b7961 100644
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -451,12 +451,16 @@ static void fat_write_super(struct super_block *sb)
 
 static int fat_sync_fs(struct super_block *sb, int wait)
 {
-	lock_super(sb);
-	fat_clusters_flush(sb);
-	sb->s_dirt = 0;
-	unlock_super(sb);
+	int err = 0;
 
-	return 0;
+	if (sb->s_dirt) {
+		lock_super(sb);
+		sb->s_dirt = 0;
+		err = fat_clusters_flush(sb);
+		unlock_super(sb);
+	}
+
+	return err;
 }
 
 static void fat_put_super(struct super_block *sb)
@@ -470,19 +474,11 @@ static void fat_put_super(struct super_block *sb)
 
 	iput(sbi->fat_inode);
 
-	if (sbi->nls_disk) {
-		unload_nls(sbi->nls_disk);
-		sbi->nls_disk = NULL;
-		sbi->options.codepage = fat_default_codepage;
-	}
-	if (sbi->nls_io) {
-		unload_nls(sbi->nls_io);
-		sbi->nls_io = NULL;
-	}
-	if (sbi->options.iocharset != fat_default_iocharset) {
+	unload_nls(sbi->nls_disk);
+	unload_nls(sbi->nls_io);
+
+	if (sbi->options.iocharset != fat_default_iocharset)
 		kfree(sbi->options.iocharset);
-		sbi->options.iocharset = fat_default_iocharset;
-	}
 
 	sb->s_fs_info = NULL;
 	kfree(sbi);
@@ -820,7 +816,7 @@ static int fat_show_options(struct seq_file *m, struct vfsmount *mnt)
 			seq_puts(m, ",shortname=mixed");
 			break;
 		case VFAT_SFN_DISPLAY_LOWER | VFAT_SFN_CREATE_WIN95:
-			/* seq_puts(m, ",shortname=lower"); */
+			seq_puts(m, ",shortname=lower");
 			break;
 		default:
 			seq_puts(m, ",shortname=unknown");
@@ -971,7 +967,7 @@ static int parse_options(char *options, int is_vfat, int silent, int *debug,
 	opts->codepage = fat_default_codepage;
 	opts->iocharset = fat_default_iocharset;
 	if (is_vfat) {
-		opts->shortname = VFAT_SFN_DISPLAY_LOWER|VFAT_SFN_CREATE_WIN95;
+		opts->shortname = VFAT_SFN_DISPLAY_WINNT|VFAT_SFN_CREATE_WIN95;
 		opts->rodir = 0;
 	} else {
 		opts->shortname = 0;
diff --git a/fs/fat/misc.c b/fs/fat/misc.c
index 4e35be8..0f55f5c 100644
--- a/fs/fat/misc.c
+++ b/fs/fat/misc.c
@@ -43,19 +43,19 @@ EXPORT_SYMBOL_GPL(fat_fs_error);
 
 /* Flushes the number of free clusters on FAT32 */
 /* XXX: Need to write one per FSINFO block.  Currently only writes 1 */
-void fat_clusters_flush(struct super_block *sb)
+int fat_clusters_flush(struct super_block *sb)
 {
 	struct msdos_sb_info *sbi = MSDOS_SB(sb);
 	struct buffer_head *bh;
 	struct fat_boot_fsinfo *fsinfo;
 
 	if (sbi->fat_bits != 32)
-		return;
+		return 0;
 
 	bh = sb_bread(sb, sbi->fsinfo_sector);
 	if (bh == NULL) {
 		printk(KERN_ERR "FAT: bread failed in fat_clusters_flush\n");
-		return;
+		return -EIO;
 	}
 
 	fsinfo = (struct fat_boot_fsinfo *)bh->b_data;
@@ -74,6 +74,8 @@ void fat_clusters_flush(struct super_block *sb)
 		mark_buffer_dirty(bh);
 	}
 	brelse(bh);
+
+	return 0;
 }
 
 /*
diff --git a/fs/fat/namei_vfat.c b/fs/fat/namei_vfat.c
index cb6e835..f565f24 100644
--- a/fs/fat/namei_vfat.c
+++ b/fs/fat/namei_vfat.c
@@ -499,17 +499,10 @@ xlate_to_uni(const unsigned char *name, int len, unsigned char *outname,
 	int charlen;
 
 	if (utf8) {
-		int name_len = strlen(name);
-
-		*outlen = utf8s_to_utf16s(name, PATH_MAX, (wchar_t *) outname);
-
-		/*
-		 * We stripped '.'s before and set len appropriately,
-		 * but utf8s_to_utf16s doesn't care about len
-		 */
-		*outlen -= (name_len - len);
-
-		if (*outlen > 255)
+		*outlen = utf8s_to_utf16s(name, len, (wchar_t *)outname);
+		if (*outlen < 0)
+			return *outlen;
+		else if (*outlen > 255)
 			return -ENAMETOOLONG;
 
 		op = &outname[*outlen * sizeof(wchar_t)];
diff --git a/fs/fcntl.c b/fs/fcntl.c
index ae41308..fc089f2 100644
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -263,6 +263,79 @@ pid_t f_getown(struct file *filp)
 	return pid;
 }
 
+static int f_setown_ex(struct file *filp, unsigned long arg)
+{
+	struct f_owner_ex * __user owner_p = (void * __user)arg;
+	struct f_owner_ex owner;
+	struct pid *pid;
+	int type;
+	int ret;
+
+	ret = copy_from_user(&owner, owner_p, sizeof(owner));
+	if (ret)
+		return ret;
+
+	switch (owner.type) {
+	case F_OWNER_TID:
+		type = PIDTYPE_MAX;
+		break;
+
+	case F_OWNER_PID:
+		type = PIDTYPE_PID;
+		break;
+
+	case F_OWNER_GID:
+		type = PIDTYPE_PGID;
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	rcu_read_lock();
+	pid = find_vpid(owner.pid);
+	if (owner.pid && !pid)
+		ret = -ESRCH;
+	else
+		ret = __f_setown(filp, pid, type, 1);
+	rcu_read_unlock();
+
+	return ret;
+}
+
+static int f_getown_ex(struct file *filp, unsigned long arg)
+{
+	struct f_owner_ex * __user owner_p = (void * __user)arg;
+	struct f_owner_ex owner;
+	int ret = 0;
+
+	read_lock(&filp->f_owner.lock);
+	owner.pid = pid_vnr(filp->f_owner.pid);
+	switch (filp->f_owner.pid_type) {
+	case PIDTYPE_MAX:
+		owner.type = F_OWNER_TID;
+		break;
+
+	case PIDTYPE_PID:
+		owner.type = F_OWNER_PID;
+		break;
+
+	case PIDTYPE_PGID:
+		owner.type = F_OWNER_GID;
+		break;
+
+	default:
+		WARN_ON(1);
+		ret = -EINVAL;
+		break;
+	}
+	read_unlock(&filp->f_owner.lock);
+
+	if (!ret)
+		ret = copy_to_user(owner_p, &owner, sizeof(owner));
+	return ret;
+}
+
 static long do_fcntl(int fd, unsigned int cmd, unsigned long arg,
 		struct file *filp)
 {
@@ -313,6 +386,12 @@ static long do_fcntl(int fd, unsigned int cmd, unsigned long arg,
 	case F_SETOWN:
 		err = f_setown(filp, arg, 1);
 		break;
+	case F_GETOWN_EX:
+		err = f_getown_ex(filp, arg);
+		break;
+	case F_SETOWN_EX:
+		err = f_setown_ex(filp, arg);
+		break;
 	case F_GETSIG:
 		err = filp->f_owner.signum;
 		break;
@@ -428,8 +507,7 @@ static inline int sigio_perm(struct task_struct *p,
 
 static void send_sigio_to_task(struct task_struct *p,
 			       struct fown_struct *fown,
-			       int fd,
-			       int reason)
+			       int fd, int reason, int group)
 {
 	/*
 	 * F_SETSIG can change ->signum lockless in parallel, make
@@ -461,11 +539,11 @@ static void send_sigio_to_task(struct task_struct *p,
 			else
 				si.si_band = band_table[reason - POLL_IN];
 			si.si_fd    = fd;
-			if (!group_send_sig_info(signum, &si, p))
+			if (!do_send_sig_info(signum, &si, p, group))
 				break;
 		/* fall-through: fall back on the old plain SIGIO signal */
 		case 0:
-			group_send_sig_info(SIGIO, SEND_SIG_PRIV, p);
+			do_send_sig_info(SIGIO, SEND_SIG_PRIV, p, group);
 	}
 }
 
@@ -474,16 +552,23 @@ void send_sigio(struct fown_struct *fown, int fd, int band)
 	struct task_struct *p;
 	enum pid_type type;
 	struct pid *pid;
+	int group = 1;
 	
 	read_lock(&fown->lock);
+
 	type = fown->pid_type;
+	if (type == PIDTYPE_MAX) {
+		group = 0;
+		type = PIDTYPE_PID;
+	}
+
 	pid = fown->pid;
 	if (!pid)
 		goto out_unlock_fown;
 	
 	read_lock(&tasklist_lock);
 	do_each_pid_task(pid, type, p) {
-		send_sigio_to_task(p, fown, fd, band);
+		send_sigio_to_task(p, fown, fd, band, group);
 	} while_each_pid_task(pid, type, p);
 	read_unlock(&tasklist_lock);
  out_unlock_fown:
@@ -491,10 +576,10 @@ void send_sigio(struct fown_struct *fown, int fd, int band)
 }
 
 static void send_sigurg_to_task(struct task_struct *p,
-                                struct fown_struct *fown)
+				struct fown_struct *fown, int group)
 {
 	if (sigio_perm(p, fown, SIGURG))
-		group_send_sig_info(SIGURG, SEND_SIG_PRIV, p);
+		do_send_sig_info(SIGURG, SEND_SIG_PRIV, p, group);
 }
 
 int send_sigurg(struct fown_struct *fown)
@@ -502,10 +587,17 @@ int send_sigurg(struct fown_struct *fown)
 	struct task_struct *p;
 	enum pid_type type;
 	struct pid *pid;
+	int group = 1;
 	int ret = 0;
 	
 	read_lock(&fown->lock);
+
 	type = fown->pid_type;
+	if (type == PIDTYPE_MAX) {
+		group = 0;
+		type = PIDTYPE_PID;
+	}
+
 	pid = fown->pid;
 	if (!pid)
 		goto out_unlock_fown;
@@ -514,7 +606,7 @@ int send_sigurg(struct fown_struct *fown)
 	
 	read_lock(&tasklist_lock);
 	do_each_pid_task(pid, type, p) {
-		send_sigurg_to_task(p, fown);
+		send_sigurg_to_task(p, fown, group);
 	} while_each_pid_task(pid, type, p);
 	read_unlock(&tasklist_lock);
  out_unlock_fown:
diff --git a/fs/file.c b/fs/file.c
index f313314..87e1290 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -10,6 +10,7 @@
 #include <linux/fs.h>
 #include <linux/mm.h>
 #include <linux/time.h>
+#include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/vmalloc.h>
 #include <linux/file.h>
diff --git a/fs/file_table.c b/fs/file_table.c
index 334ce39..8eb4404 100644
--- a/fs/file_table.c
+++ b/fs/file_table.c
@@ -74,14 +74,14 @@ EXPORT_SYMBOL_GPL(get_max_files);
  * Handle nr_files sysctl
  */
 #if defined(CONFIG_SYSCTL) && defined(CONFIG_PROC_FS)
-int proc_nr_files(ctl_table *table, int write, struct file *filp,
+int proc_nr_files(ctl_table *table, int write,
                      void __user *buffer, size_t *lenp, loff_t *ppos)
 {
 	files_stat.nr_files = get_nr_files();
-	return proc_dointvec(table, write, filp, buffer, lenp, ppos);
+	return proc_dointvec(table, write, buffer, lenp, ppos);
 }
 #else
-int proc_nr_files(ctl_table *table, int write, struct file *filp,
+int proc_nr_files(ctl_table *table, int write,
                      void __user *buffer, size_t *lenp, loff_t *ppos)
 {
 	return -ENOSYS;
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 8e1e5e1..9d5360c 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -41,8 +41,9 @@ struct wb_writeback_args {
 	long nr_pages;
 	struct super_block *sb;
 	enum writeback_sync_modes sync_mode;
-	int for_kupdate;
-	int range_cyclic;
+	int for_kupdate:1;
+	int range_cyclic:1;
+	int for_background:1;
 };
 
 /*
@@ -249,14 +250,25 @@ static void bdi_sync_writeback(struct backing_dev_info *bdi,
  *   completion. Caller need not hold sb s_umount semaphore.
  *
  */
-void bdi_start_writeback(struct backing_dev_info *bdi, long nr_pages)
+void bdi_start_writeback(struct backing_dev_info *bdi, struct super_block *sb,
+			 long nr_pages)
 {
 	struct wb_writeback_args args = {
+		.sb		= sb,
 		.sync_mode	= WB_SYNC_NONE,
 		.nr_pages	= nr_pages,
 		.range_cyclic	= 1,
 	};
 
+	/*
+	 * We treat @nr_pages=0 as the special case to do background writeback,
+	 * ie. to sync pages until the background dirty threshold is reached.
+	 */
+	if (!nr_pages) {
+		args.nr_pages = LONG_MAX;
+		args.for_background = 1;
+	}
+
 	bdi_alloc_queue_work(bdi, &args);
 }
 
@@ -310,7 +322,7 @@ static bool inode_dirtied_after(struct inode *inode, unsigned long t)
 	 * For inodes being constantly redirtied, dirtied_when can get stuck.
 	 * It _appears_ to be in the future, but is actually in distant past.
 	 * This test is necessary to prevent such wrapped-around relative times
-	 * from permanently stopping the whole pdflush writeback.
+	 * from permanently stopping the whole bdi writeback.
 	 */
 	ret = ret && time_before_eq(inode->dirtied_when, jiffies);
 #endif
@@ -324,13 +336,38 @@ static void move_expired_inodes(struct list_head *delaying_queue,
 			       struct list_head *dispatch_queue,
 				unsigned long *older_than_this)
 {
+	LIST_HEAD(tmp);
+	struct list_head *pos, *node;
+	struct super_block *sb = NULL;
+	struct inode *inode;
+	int do_sb_sort = 0;
+
 	while (!list_empty(delaying_queue)) {
-		struct inode *inode = list_entry(delaying_queue->prev,
-						struct inode, i_list);
+		inode = list_entry(delaying_queue->prev, struct inode, i_list);
 		if (older_than_this &&
 		    inode_dirtied_after(inode, *older_than_this))
 			break;
-		list_move(&inode->i_list, dispatch_queue);
+		if (sb && sb != inode->i_sb)
+			do_sb_sort = 1;
+		sb = inode->i_sb;
+		list_move(&inode->i_list, &tmp);
+	}
+
+	/* just one sb in list, splice to dispatch_queue and we're done */
+	if (!do_sb_sort) {
+		list_splice(&tmp, dispatch_queue);
+		return;
+	}
+
+	/* Move inodes from one superblock together */
+	while (!list_empty(&tmp)) {
+		inode = list_entry(tmp.prev, struct inode, i_list);
+		sb = inode->i_sb;
+		list_for_each_prev_safe(pos, node, &tmp) {
+			inode = list_entry(pos, struct inode, i_list);
+			if (inode->i_sb == sb)
+				list_move(&inode->i_list, dispatch_queue);
+		}
 	}
 }
 
@@ -439,8 +476,18 @@ writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
 	spin_lock(&inode_lock);
 	inode->i_state &= ~I_SYNC;
 	if (!(inode->i_state & (I_FREEING | I_CLEAR))) {
-		if (!(inode->i_state & I_DIRTY) &&
-		    mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) {
+		if ((inode->i_state & I_DIRTY_PAGES) && wbc->for_kupdate) {
+			/*
+			 * More pages get dirtied by a fast dirtier.
+			 */
+			goto select_queue;
+		} else if (inode->i_state & I_DIRTY) {
+			/*
+			 * At least XFS will redirty the inode during the
+			 * writeback (delalloc) and on io completion (isize).
+			 */
+			redirty_tail(inode);
+		} else if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) {
 			/*
 			 * We didn't write back all the pages.  nfs_writepages()
 			 * sometimes bales out without doing anything. Redirty
@@ -462,6 +509,7 @@ writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
 				 * soon as the queue becomes uncongested.
 				 */
 				inode->i_state |= I_DIRTY_PAGES;
+select_queue:
 				if (wbc->nr_to_write <= 0) {
 					/*
 					 * slice used up: queue for next turn
@@ -484,12 +532,6 @@ writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
 				inode->i_state |= I_DIRTY_PAGES;
 				redirty_tail(inode);
 			}
-		} else if (inode->i_state & I_DIRTY) {
-			/*
-			 * Someone redirtied the inode while were writing back
-			 * the pages.
-			 */
-			redirty_tail(inode);
 		} else if (atomic_read(&inode->i_count)) {
 			/*
 			 * The inode is clean, inuse
@@ -506,6 +548,17 @@ writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
 	return ret;
 }
 
+static void unpin_sb_for_writeback(struct super_block **psb)
+{
+	struct super_block *sb = *psb;
+
+	if (sb) {
+		up_read(&sb->s_umount);
+		put_super(sb);
+		*psb = NULL;
+	}
+}
+
 /*
  * For WB_SYNC_NONE writeback, the caller does not have the sb pinned
  * before calling writeback. So make sure that we do pin it, so it doesn't
@@ -515,11 +568,20 @@ writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
  * 1 if we failed.
  */
 static int pin_sb_for_writeback(struct writeback_control *wbc,
-				   struct inode *inode)
+				struct inode *inode, struct super_block **psb)
 {
 	struct super_block *sb = inode->i_sb;
 
 	/*
+	 * If this sb is already pinned, nothing more to do. If not and
+	 * *psb is non-NULL, unpin the old one first
+	 */
+	if (sb == *psb)
+		return 0;
+	else if (*psb)
+		unpin_sb_for_writeback(psb);
+
+	/*
 	 * Caller must already hold the ref for this
 	 */
 	if (wbc->sync_mode == WB_SYNC_ALL) {
@@ -532,7 +594,7 @@ static int pin_sb_for_writeback(struct writeback_control *wbc,
 	if (down_read_trylock(&sb->s_umount)) {
 		if (sb->s_root) {
 			spin_unlock(&sb_lock);
-			return 0;
+			goto pinned;
 		}
 		/*
 		 * umounted, drop rwsem again and fall through to failure
@@ -543,24 +605,15 @@ static int pin_sb_for_writeback(struct writeback_control *wbc,
 	sb->s_count--;
 	spin_unlock(&sb_lock);
 	return 1;
-}
-
-static void unpin_sb_for_writeback(struct writeback_control *wbc,
-				   struct inode *inode)
-{
-	struct super_block *sb = inode->i_sb;
-
-	if (wbc->sync_mode == WB_SYNC_ALL)
-		return;
-
-	up_read(&sb->s_umount);
-	put_super(sb);
+pinned:
+	*psb = sb;
+	return 0;
 }
 
 static void writeback_inodes_wb(struct bdi_writeback *wb,
 				struct writeback_control *wbc)
 {
-	struct super_block *sb = wbc->sb;
+	struct super_block *sb = wbc->sb, *pin_sb = NULL;
 	const int is_blkdev_sb = sb_is_blkdev_sb(sb);
 	const unsigned long start = jiffies;	/* livelock avoidance */
 
@@ -619,7 +672,7 @@ static void writeback_inodes_wb(struct bdi_writeback *wb,
 		if (inode_dirtied_after(inode, start))
 			break;
 
-		if (pin_sb_for_writeback(wbc, inode)) {
+		if (pin_sb_for_writeback(wbc, inode, &pin_sb)) {
 			requeue_io(inode);
 			continue;
 		}
@@ -628,7 +681,6 @@ static void writeback_inodes_wb(struct bdi_writeback *wb,
 		__iget(inode);
 		pages_skipped = wbc->pages_skipped;
 		writeback_single_inode(inode, wbc);
-		unpin_sb_for_writeback(wbc, inode);
 		if (wbc->pages_skipped != pages_skipped) {
 			/*
 			 * writeback is not making progress due to locked
@@ -648,6 +700,8 @@ static void writeback_inodes_wb(struct bdi_writeback *wb,
 			wbc->more_io = 1;
 	}
 
+	unpin_sb_for_writeback(&pin_sb);
+
 	spin_unlock(&inode_lock);
 	/* Leave any unwritten inodes on b_io */
 }
@@ -706,6 +760,7 @@ static long wb_writeback(struct bdi_writeback *wb,
 	};
 	unsigned long oldest_jif;
 	long wrote = 0;
+	struct inode *inode;
 
 	if (wbc.for_kupdate) {
 		wbc.older_than_this = &oldest_jif;
@@ -719,20 +774,16 @@ static long wb_writeback(struct bdi_writeback *wb,
 
 	for (;;) {
 		/*
-		 * Don't flush anything for non-integrity writeback where
-		 * no nr_pages was given
+		 * Stop writeback when nr_pages has been consumed
 		 */
-		if (!args->for_kupdate && args->nr_pages <= 0 &&
-		     args->sync_mode == WB_SYNC_NONE)
+		if (args->nr_pages <= 0)
 			break;
 
 		/*
-		 * If no specific pages were given and this is just a
-		 * periodic background writeout and we are below the
-		 * background dirty threshold, don't do anything
+		 * For background writeout, stop when we are below the
+		 * background dirty threshold
 		 */
-		if (args->for_kupdate && args->nr_pages <= 0 &&
-		    !over_bground_thresh())
+		if (args->for_background && !over_bground_thresh())
 			break;
 
 		wbc.more_io = 0;
@@ -744,13 +795,32 @@ static long wb_writeback(struct bdi_writeback *wb,
 		wrote += MAX_WRITEBACK_PAGES - wbc.nr_to_write;
 
 		/*
-		 * If we ran out of stuff to write, bail unless more_io got set
+		 * If we consumed everything, see if we have more
 		 */
-		if (wbc.nr_to_write > 0 || wbc.pages_skipped > 0) {
-			if (wbc.more_io && !wbc.for_kupdate)
-				continue;
+		if (wbc.nr_to_write <= 0)
+			continue;
+		/*
+		 * Didn't write everything and we don't have more IO, bail
+		 */
+		if (!wbc.more_io)
 			break;
+		/*
+		 * Did we write something? Try for more
+		 */
+		if (wbc.nr_to_write < MAX_WRITEBACK_PAGES)
+			continue;
+		/*
+		 * Nothing written. Wait for some inode to
+		 * become available for writeback. Otherwise
+		 * we'll just busyloop.
+		 */
+		spin_lock(&inode_lock);
+		if (!list_empty(&wb->b_more_io))  {
+			inode = list_entry(wb->b_more_io.prev,
+						struct inode, i_list);
+			inode_wait_for_writeback(inode);
 		}
+		spin_unlock(&inode_lock);
 	}
 
 	return wrote;
@@ -1060,9 +1130,6 @@ EXPORT_SYMBOL(__mark_inode_dirty);
  * If older_than_this is non-NULL, then only write out inodes which
  * had their first dirtying at a time earlier than *older_than_this.
  *
- * If we're a pdlfush thread, then implement pdflush collision avoidance
- * against the entire list.
- *
  * If `bdi' is non-zero then we're being asked to writeback a specific queue.
  * This function assumes that the blockdev superblock's inodes are backed by
  * a variety of queues, so all inodes are searched.  For other superblocks,
@@ -1141,7 +1208,7 @@ void writeback_inodes_sb(struct super_block *sb)
 	nr_to_write = nr_dirty + nr_unstable +
 			(inodes_stat.nr_inodes - inodes_stat.nr_unused);
 
-	bdi_writeback_all(sb, nr_to_write);
+	bdi_start_writeback(sb->s_bdi, sb, nr_to_write);
 }
 EXPORT_SYMBOL(writeback_inodes_sb);
 
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index e703654..992f6c9 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -1276,14 +1276,9 @@ static int fuse_do_setattr(struct dentry *entry, struct iattr *attr,
 		return 0;
 
 	if (attr->ia_valid & ATTR_SIZE) {
-		unsigned long limit;
-		if (IS_SWAPFILE(inode))
-			return -ETXTBSY;
-		limit = current->signal->rlim[RLIMIT_FSIZE].rlim_cur;
-		if (limit != RLIM_INFINITY && attr->ia_size > (loff_t) limit) {
-			send_sig(SIGXFSZ, current, 0);
-			return -EFBIG;
-		}
+		err = inode_newsize_ok(inode, attr->ia_size);
+		if (err)
+			return err;
 		is_truncate = true;
 	}
 
@@ -1350,8 +1345,7 @@ static int fuse_do_setattr(struct dentry *entry, struct iattr *attr,
 	 * FUSE_NOWRITE, otherwise fuse_launder_page() would deadlock.
 	 */
 	if (S_ISREG(inode->i_mode) && oldsize != outarg.attr.size) {
-		if (outarg.attr.size < oldsize)
-			fuse_truncate(inode->i_mapping, outarg.attr.size);
+		truncate_pagecache(inode, oldsize, outarg.attr.size);
 		invalidate_inode_pages2(inode->i_mapping);
 	}
 
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index cbc4640..a3492f7 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -1313,7 +1313,7 @@ static int fuse_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
 	return 0;
 }
 
-static struct vm_operations_struct fuse_file_vm_ops = {
+static const struct vm_operations_struct fuse_file_vm_ops = {
 	.close		= fuse_vma_close,
 	.fault		= filemap_fault,
 	.page_mkwrite	= fuse_page_mkwrite,
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index fc9c79f..01cc462 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -606,8 +606,6 @@ void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
 void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr,
 				   u64 attr_valid);
 
-void fuse_truncate(struct address_space *mapping, loff_t offset);
-
 /**
  * Initialize the client device
  */
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index 6da947d..1a822ce 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -140,14 +140,6 @@ static int fuse_remount_fs(struct super_block *sb, int *flags, char *data)
 	return 0;
 }
 
-void fuse_truncate(struct address_space *mapping, loff_t offset)
-{
-	/* See vmtruncate() */
-	unmap_mapping_range(mapping, offset + PAGE_SIZE - 1, 0, 1);
-	truncate_inode_pages(mapping, offset);
-	unmap_mapping_range(mapping, offset + PAGE_SIZE - 1, 0, 1);
-}
-
 void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr,
 				   u64 attr_valid)
 {
@@ -205,8 +197,7 @@ void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
 	spin_unlock(&fc->lock);
 
 	if (S_ISREG(inode->i_mode) && oldsize != attr->size) {
-		if (attr->size < oldsize)
-			fuse_truncate(inode->i_mapping, attr->size);
+		truncate_pagecache(inode, oldsize, attr->size);
 		invalidate_inode_pages2(inode->i_mapping);
 	}
 }
diff --git a/fs/gfs2/aops.c b/fs/gfs2/aops.c
index 7ebae9a..694b5d4 100644
--- a/fs/gfs2/aops.c
+++ b/fs/gfs2/aops.c
@@ -1135,6 +1135,7 @@ static const struct address_space_operations gfs2_writeback_aops = {
 	.direct_IO = gfs2_direct_IO,
 	.migratepage = buffer_migrate_page,
 	.is_partially_uptodate = block_is_partially_uptodate,
+	.error_remove_page = generic_error_remove_page,
 };
 
 static const struct address_space_operations gfs2_ordered_aops = {
@@ -1151,6 +1152,7 @@ static const struct address_space_operations gfs2_ordered_aops = {
 	.direct_IO = gfs2_direct_IO,
 	.migratepage = buffer_migrate_page,
 	.is_partially_uptodate = block_is_partially_uptodate,
+	.error_remove_page = generic_error_remove_page,
 };
 
 static const struct address_space_operations gfs2_jdata_aops = {
@@ -1166,6 +1168,7 @@ static const struct address_space_operations gfs2_jdata_aops = {
 	.invalidatepage = gfs2_invalidatepage,
 	.releasepage = gfs2_releasepage,
 	.is_partially_uptodate = block_is_partially_uptodate,
+	.error_remove_page = generic_error_remove_page,
 };
 
 void gfs2_set_aops(struct inode *inode)
diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c
index 166f38f..4eb308a 100644
--- a/fs/gfs2/file.c
+++ b/fs/gfs2/file.c
@@ -418,7 +418,7 @@ out:
 	return ret;
 }
 
-static struct vm_operations_struct gfs2_vm_ops = {
+static const struct vm_operations_struct gfs2_vm_ops = {
 	.fault = filemap_fault,
 	.page_mkwrite = gfs2_page_mkwrite,
 };
diff --git a/fs/gfs2/ops_inode.c b/fs/gfs2/ops_inode.c
index c3ac180..247436c 100644
--- a/fs/gfs2/ops_inode.c
+++ b/fs/gfs2/ops_inode.c
@@ -12,7 +12,6 @@
 #include <linux/completion.h>
 #include <linux/buffer_head.h>
 #include <linux/namei.h>
-#include <linux/utsname.h>
 #include <linux/mm.h>
 #include <linux/xattr.h>
 #include <linux/posix_acl.h>
diff --git a/fs/hfs/mdb.c b/fs/hfs/mdb.c
index 7b6165f..8bbe03c 100644
--- a/fs/hfs/mdb.c
+++ b/fs/hfs/mdb.c
@@ -344,10 +344,8 @@ void hfs_mdb_put(struct super_block *sb)
 	brelse(HFS_SB(sb)->mdb_bh);
 	brelse(HFS_SB(sb)->alt_mdb_bh);
 
-	if (HFS_SB(sb)->nls_io)
-		unload_nls(HFS_SB(sb)->nls_io);
-	if (HFS_SB(sb)->nls_disk)
-		unload_nls(HFS_SB(sb)->nls_disk);
+	unload_nls(HFS_SB(sb)->nls_io);
+	unload_nls(HFS_SB(sb)->nls_disk);
 
 	free_pages((unsigned long)HFS_SB(sb)->bitmap, PAGE_SIZE < 8192 ? 1 : 0);
 	kfree(HFS_SB(sb));
diff --git a/fs/hfsplus/super.c b/fs/hfsplus/super.c
index c0759fe..43022f3 100644
--- a/fs/hfsplus/super.c
+++ b/fs/hfsplus/super.c
@@ -229,8 +229,7 @@ static void hfsplus_put_super(struct super_block *sb)
 	iput(HFSPLUS_SB(sb).alloc_file);
 	iput(HFSPLUS_SB(sb).hidden_dir);
 	brelse(HFSPLUS_SB(sb).s_vhbh);
-	if (HFSPLUS_SB(sb).nls)
-		unload_nls(HFSPLUS_SB(sb).nls);
+	unload_nls(HFSPLUS_SB(sb).nls);
 	kfree(sb->s_fs_info);
 	sb->s_fs_info = NULL;
 
@@ -464,8 +463,7 @@ out:
 
 cleanup:
 	hfsplus_put_super(sb);
-	if (nls)
-		unload_nls(nls);
+	unload_nls(nls);
 	return err;
 }
 
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index eba6d552d..87a1258 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -380,36 +380,11 @@ static void hugetlbfs_delete_inode(struct inode *inode)
 
 static void hugetlbfs_forget_inode(struct inode *inode) __releases(inode_lock)
 {
-	struct super_block *sb = inode->i_sb;
-
-	if (!hlist_unhashed(&inode->i_hash)) {
-		if (!(inode->i_state & (I_DIRTY|I_SYNC)))
-			list_move(&inode->i_list, &inode_unused);
-		inodes_stat.nr_unused++;
-		if (!sb || (sb->s_flags & MS_ACTIVE)) {
-			spin_unlock(&inode_lock);
-			return;
-		}
-		inode->i_state |= I_WILL_FREE;
-		spin_unlock(&inode_lock);
-		/*
-		 * write_inode_now is a noop as we set BDI_CAP_NO_WRITEBACK
-		 * in our backing_dev_info.
-		 */
-		write_inode_now(inode, 1);
-		spin_lock(&inode_lock);
-		inode->i_state &= ~I_WILL_FREE;
-		inodes_stat.nr_unused--;
-		hlist_del_init(&inode->i_hash);
+	if (generic_detach_inode(inode)) {
+		truncate_hugepages(inode, 0);
+		clear_inode(inode);
+		destroy_inode(inode);
 	}
-	list_del_init(&inode->i_list);
-	list_del_init(&inode->i_sb_list);
-	inode->i_state |= I_FREEING;
-	inodes_stat.nr_inodes--;
-	spin_unlock(&inode_lock);
-	truncate_hugepages(inode, 0);
-	clear_inode(inode);
-	destroy_inode(inode);
 }
 
 static void hugetlbfs_drop_inode(struct inode *inode)
@@ -936,15 +911,9 @@ static struct file_system_type hugetlbfs_fs_type = {
 
 static struct vfsmount *hugetlbfs_vfsmount;
 
-static int can_do_hugetlb_shm(int creat_flags)
+static int can_do_hugetlb_shm(void)
 {
-	if (creat_flags != HUGETLB_SHMFS_INODE)
-		return 0;
-	if (capable(CAP_IPC_LOCK))
-		return 1;
-	if (in_group_p(sysctl_hugetlb_shm_group))
-		return 1;
-	return 0;
+	return capable(CAP_IPC_LOCK) || in_group_p(sysctl_hugetlb_shm_group);
 }
 
 struct file *hugetlb_file_setup(const char *name, size_t size, int acctflag,
@@ -960,7 +929,7 @@ struct file *hugetlb_file_setup(const char *name, size_t size, int acctflag,
 	if (!hugetlbfs_vfsmount)
 		return ERR_PTR(-ENOENT);
 
-	if (!can_do_hugetlb_shm(creat_flags)) {
+	if (creat_flags == HUGETLB_SHMFS_INODE && !can_do_hugetlb_shm()) {
 		*user = current_user();
 		if (user_shm_lock(size, *user)) {
 			WARN_ONCE(1,
diff --git a/fs/inode.c b/fs/inode.c
index 76582b06..4d8e3be 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1241,7 +1241,16 @@ void generic_delete_inode(struct inode *inode)
 }
 EXPORT_SYMBOL(generic_delete_inode);
 
-static void generic_forget_inode(struct inode *inode)
+/**
+ *	generic_detach_inode - remove inode from inode lists
+ *	@inode: inode to remove
+ *
+ *	Remove inode from inode lists, write it if it's dirty. This is just an
+ *	internal VFS helper exported for hugetlbfs. Do not use!
+ *
+ *	Returns 1 if inode should be completely destroyed.
+ */
+int generic_detach_inode(struct inode *inode)
 {
 	struct super_block *sb = inode->i_sb;
 
@@ -1251,7 +1260,7 @@ static void generic_forget_inode(struct inode *inode)
 		inodes_stat.nr_unused++;
 		if (sb->s_flags & MS_ACTIVE) {
 			spin_unlock(&inode_lock);
-			return;
+			return 0;
 		}
 		WARN_ON(inode->i_state & I_NEW);
 		inode->i_state |= I_WILL_FREE;
@@ -1269,6 +1278,14 @@ static void generic_forget_inode(struct inode *inode)
 	inode->i_state |= I_FREEING;
 	inodes_stat.nr_inodes--;
 	spin_unlock(&inode_lock);
+	return 1;
+}
+EXPORT_SYMBOL_GPL(generic_detach_inode);
+
+static void generic_forget_inode(struct inode *inode)
+{
+	if (!generic_detach_inode(inode))
+		return;
 	if (inode->i_data.nrpages)
 		truncate_inode_pages(&inode->i_data, 0);
 	clear_inode(inode);
@@ -1399,31 +1416,31 @@ void touch_atime(struct vfsmount *mnt, struct dentry *dentry)
 	struct inode *inode = dentry->d_inode;
 	struct timespec now;
 
-	if (mnt_want_write(mnt))
-		return;
 	if (inode->i_flags & S_NOATIME)
-		goto out;
+		return;
 	if (IS_NOATIME(inode))
-		goto out;
+		return;
 	if ((inode->i_sb->s_flags & MS_NODIRATIME) && S_ISDIR(inode->i_mode))
-		goto out;
+		return;
 
 	if (mnt->mnt_flags & MNT_NOATIME)
-		goto out;
+		return;
 	if ((mnt->mnt_flags & MNT_NODIRATIME) && S_ISDIR(inode->i_mode))
-		goto out;
+		return;
 
 	now = current_fs_time(inode->i_sb);
 
 	if (!relatime_need_update(mnt, inode, now))
-		goto out;
+		return;
 
 	if (timespec_equal(&inode->i_atime, &now))
-		goto out;
+		return;
+
+	if (mnt_want_write(mnt))
+		return;
 
 	inode->i_atime = now;
 	mark_inode_dirty_sync(inode);
-out:
 	mnt_drop_write(mnt);
 }
 EXPORT_SYMBOL(touch_atime);
@@ -1444,34 +1461,37 @@ void file_update_time(struct file *file)
 {
 	struct inode *inode = file->f_path.dentry->d_inode;
 	struct timespec now;
-	int sync_it = 0;
-	int err;
+	enum { S_MTIME = 1, S_CTIME = 2, S_VERSION = 4 } sync_it = 0;
 
+	/* First try to exhaust all avenues to not sync */
 	if (IS_NOCMTIME(inode))
 		return;
 
-	err = mnt_want_write_file(file);
-	if (err)
-		return;
-
 	now = current_fs_time(inode->i_sb);
-	if (!timespec_equal(&inode->i_mtime, &now)) {
-		inode->i_mtime = now;
-		sync_it = 1;
-	}
+	if (!timespec_equal(&inode->i_mtime, &now))
+		sync_it = S_MTIME;
 
-	if (!timespec_equal(&inode->i_ctime, &now)) {
-		inode->i_ctime = now;
-		sync_it = 1;
-	}
+	if (!timespec_equal(&inode->i_ctime, &now))
+		sync_it |= S_CTIME;
 
-	if (IS_I_VERSION(inode)) {
-		inode_inc_iversion(inode);
-		sync_it = 1;
-	}
+	if (IS_I_VERSION(inode))
+		sync_it |= S_VERSION;
+
+	if (!sync_it)
+		return;
 
-	if (sync_it)
-		mark_inode_dirty_sync(inode);
+	/* Finally allowed to write? Takes lock. */
+	if (mnt_want_write_file(file))
+		return;
+
+	/* Only change inode inside the lock region */
+	if (sync_it & S_VERSION)
+		inode_inc_iversion(inode);
+	if (sync_it & S_CTIME)
+		inode->i_ctime = now;
+	if (sync_it & S_MTIME)
+		inode->i_mtime = now;
+	mark_inode_dirty_sync(inode);
 	mnt_drop_write(file->f_path.mnt);
 }
 EXPORT_SYMBOL(file_update_time);
@@ -1599,7 +1619,8 @@ void init_special_inode(struct inode *inode, umode_t mode, dev_t rdev)
 	else if (S_ISSOCK(mode))
 		inode->i_fop = &bad_sock_fops;
 	else
-		printk(KERN_DEBUG "init_special_inode: bogus i_mode (%o)\n",
-		       mode);
+		printk(KERN_DEBUG "init_special_inode: bogus i_mode (%o) for"
+				  " inode %s:%lu\n", mode, inode->i_sb->s_id,
+				  inode->i_ino);
 }
 EXPORT_SYMBOL(init_special_inode);
diff --git a/fs/internal.h b/fs/internal.h
index d55ef56..515175b 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -57,6 +57,7 @@ extern int check_unsafe_exec(struct linux_binprm *);
  * namespace.c
  */
 extern int copy_mount_options(const void __user *, unsigned long *);
+extern int copy_mount_string(const void __user *, char **);
 
 extern void free_vfsmnt(struct vfsmount *);
 extern struct vfsmount *alloc_vfsmnt(const char *);
diff --git a/fs/ioctl.c b/fs/ioctl.c
index 5612880..7b17a14 100644
--- a/fs/ioctl.c
+++ b/fs/ioctl.c
@@ -162,20 +162,21 @@ EXPORT_SYMBOL(fiemap_check_flags);
 static int fiemap_check_ranges(struct super_block *sb,
 			       u64 start, u64 len, u64 *new_len)
 {
+	u64 maxbytes = (u64) sb->s_maxbytes;
+
 	*new_len = len;
 
 	if (len == 0)
 		return -EINVAL;
 
-	if (start > sb->s_maxbytes)
+	if (start > maxbytes)
 		return -EFBIG;
 
 	/*
 	 * Shrink request scope to what the fs can actually handle.
 	 */
-	if ((len > sb->s_maxbytes) ||
-	    (sb->s_maxbytes - len) < start)
-		*new_len = sb->s_maxbytes - start;
+	if (len > maxbytes || (maxbytes - len) < start)
+		*new_len = maxbytes - start;
 
 	return 0;
 }
diff --git a/fs/isofs/inode.c b/fs/isofs/inode.c
index 85f96bc..6b4dcd4 100644
--- a/fs/isofs/inode.c
+++ b/fs/isofs/inode.c
@@ -46,10 +46,7 @@ static void isofs_put_super(struct super_block *sb)
 #ifdef CONFIG_JOLIET
 	lock_kernel();
 
-	if (sbi->s_nls_iocharset) {
-		unload_nls(sbi->s_nls_iocharset);
-		sbi->s_nls_iocharset = NULL;
-	}
+	unload_nls(sbi->s_nls_iocharset);
 
 	unlock_kernel();
 #endif
@@ -912,8 +909,7 @@ out_no_root:
 		printk(KERN_WARNING "%s: get root inode failed\n", __func__);
 out_no_inode:
 #ifdef CONFIG_JOLIET
-	if (sbi->s_nls_iocharset)
-		unload_nls(sbi->s_nls_iocharset);
+	unload_nls(sbi->s_nls_iocharset);
 #endif
 	goto out_freesbi;
 out_no_read:
diff --git a/fs/jbd2/checkpoint.c b/fs/jbd2/checkpoint.c
index 5d70b3e..ca0f5eb 100644
--- a/fs/jbd2/checkpoint.c
+++ b/fs/jbd2/checkpoint.c
@@ -643,6 +643,7 @@ out:
 
 int __jbd2_journal_remove_checkpoint(struct journal_head *jh)
 {
+	struct transaction_chp_stats_s *stats;
 	transaction_t *transaction;
 	journal_t *journal;
 	int ret = 0;
@@ -679,6 +680,12 @@ int __jbd2_journal_remove_checkpoint(struct journal_head *jh)
 
 	/* OK, that was the last buffer for the transaction: we can now
 	   safely remove this transaction from the log */
+	stats = &transaction->t_chp_stats;
+	if (stats->cs_chp_time)
+		stats->cs_chp_time = jbd2_time_diff(stats->cs_chp_time,
+						    jiffies);
+	trace_jbd2_checkpoint_stats(journal->j_fs_dev->bd_dev,
+				    transaction->t_tid, stats);
 
 	__jbd2_journal_drop_transaction(journal, transaction);
 	kfree(transaction);
diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c
index 26d991d..d4cfd6d 100644
--- a/fs/jbd2/commit.c
+++ b/fs/jbd2/commit.c
@@ -410,10 +410,10 @@ void jbd2_journal_commit_transaction(journal_t *journal)
 	if (commit_transaction->t_synchronous_commit)
 		write_op = WRITE_SYNC_PLUG;
 	trace_jbd2_commit_locking(journal, commit_transaction);
-	stats.u.run.rs_wait = commit_transaction->t_max_wait;
-	stats.u.run.rs_locked = jiffies;
-	stats.u.run.rs_running = jbd2_time_diff(commit_transaction->t_start,
-						stats.u.run.rs_locked);
+	stats.run.rs_wait = commit_transaction->t_max_wait;
+	stats.run.rs_locked = jiffies;
+	stats.run.rs_running = jbd2_time_diff(commit_transaction->t_start,
+					      stats.run.rs_locked);
 
 	spin_lock(&commit_transaction->t_handle_lock);
 	while (commit_transaction->t_updates) {
@@ -486,9 +486,9 @@ void jbd2_journal_commit_transaction(journal_t *journal)
 	jbd2_journal_switch_revoke_table(journal);
 
 	trace_jbd2_commit_flushing(journal, commit_transaction);
-	stats.u.run.rs_flushing = jiffies;
-	stats.u.run.rs_locked = jbd2_time_diff(stats.u.run.rs_locked,
-					       stats.u.run.rs_flushing);
+	stats.run.rs_flushing = jiffies;
+	stats.run.rs_locked = jbd2_time_diff(stats.run.rs_locked,
+					     stats.run.rs_flushing);
 
 	commit_transaction->t_state = T_FLUSH;
 	journal->j_committing_transaction = commit_transaction;
@@ -523,11 +523,11 @@ void jbd2_journal_commit_transaction(journal_t *journal)
 	spin_unlock(&journal->j_state_lock);
 
 	trace_jbd2_commit_logging(journal, commit_transaction);
-	stats.u.run.rs_logging = jiffies;
-	stats.u.run.rs_flushing = jbd2_time_diff(stats.u.run.rs_flushing,
-						 stats.u.run.rs_logging);
-	stats.u.run.rs_blocks = commit_transaction->t_outstanding_credits;
-	stats.u.run.rs_blocks_logged = 0;
+	stats.run.rs_logging = jiffies;
+	stats.run.rs_flushing = jbd2_time_diff(stats.run.rs_flushing,
+					       stats.run.rs_logging);
+	stats.run.rs_blocks = commit_transaction->t_outstanding_credits;
+	stats.run.rs_blocks_logged = 0;
 
 	J_ASSERT(commit_transaction->t_nr_buffers <=
 		 commit_transaction->t_outstanding_credits);
@@ -695,7 +695,7 @@ start_journal_io:
 				submit_bh(write_op, bh);
 			}
 			cond_resched();
-			stats.u.run.rs_blocks_logged += bufs;
+			stats.run.rs_blocks_logged += bufs;
 
 			/* Force a new descriptor to be generated next
                            time round the loop. */
@@ -988,33 +988,30 @@ restart_loop:
 	J_ASSERT(commit_transaction->t_state == T_COMMIT);
 
 	commit_transaction->t_start = jiffies;
-	stats.u.run.rs_logging = jbd2_time_diff(stats.u.run.rs_logging,
-						commit_transaction->t_start);
+	stats.run.rs_logging = jbd2_time_diff(stats.run.rs_logging,
+					      commit_transaction->t_start);
 
 	/*
-	 * File the transaction for history
+	 * File the transaction statistics
 	 */
-	stats.ts_type = JBD2_STATS_RUN;
 	stats.ts_tid = commit_transaction->t_tid;
-	stats.u.run.rs_handle_count = commit_transaction->t_handle_count;
-	spin_lock(&journal->j_history_lock);
-	memcpy(journal->j_history + journal->j_history_cur, &stats,
-			sizeof(stats));
-	if (++journal->j_history_cur == journal->j_history_max)
-		journal->j_history_cur = 0;
+	stats.run.rs_handle_count = commit_transaction->t_handle_count;
+	trace_jbd2_run_stats(journal->j_fs_dev->bd_dev,
+			     commit_transaction->t_tid, &stats.run);
 
 	/*
 	 * Calculate overall stats
 	 */
+	spin_lock(&journal->j_history_lock);
 	journal->j_stats.ts_tid++;
-	journal->j_stats.u.run.rs_wait += stats.u.run.rs_wait;
-	journal->j_stats.u.run.rs_running += stats.u.run.rs_running;
-	journal->j_stats.u.run.rs_locked += stats.u.run.rs_locked;
-	journal->j_stats.u.run.rs_flushing += stats.u.run.rs_flushing;
-	journal->j_stats.u.run.rs_logging += stats.u.run.rs_logging;
-	journal->j_stats.u.run.rs_handle_count += stats.u.run.rs_handle_count;
-	journal->j_stats.u.run.rs_blocks += stats.u.run.rs_blocks;
-	journal->j_stats.u.run.rs_blocks_logged += stats.u.run.rs_blocks_logged;
+	journal->j_stats.run.rs_wait += stats.run.rs_wait;
+	journal->j_stats.run.rs_running += stats.run.rs_running;
+	journal->j_stats.run.rs_locked += stats.run.rs_locked;
+	journal->j_stats.run.rs_flushing += stats.run.rs_flushing;
+	journal->j_stats.run.rs_logging += stats.run.rs_logging;
+	journal->j_stats.run.rs_handle_count += stats.run.rs_handle_count;
+	journal->j_stats.run.rs_blocks += stats.run.rs_blocks;
+	journal->j_stats.run.rs_blocks_logged += stats.run.rs_blocks_logged;
 	spin_unlock(&journal->j_history_lock);
 
 	commit_transaction->t_state = T_FINISHED;
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index 53b86e1..b0ab521 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -136,10 +136,6 @@ static int kjournald2(void *arg)
 	journal->j_task = current;
 	wake_up(&journal->j_wait_done_commit);
 
-	printk(KERN_INFO "kjournald2 starting: pid %d, dev %s, "
-	       "commit interval %ld seconds\n", current->pid,
-	       journal->j_devname, journal->j_commit_interval / HZ);
-
 	/*
 	 * And now, wait forever for commit wakeup events.
 	 */
@@ -223,7 +219,8 @@ static int jbd2_journal_start_thread(journal_t *journal)
 {
 	struct task_struct *t;
 
-	t = kthread_run(kjournald2, journal, "kjournald2");
+	t = kthread_run(kjournald2, journal, "jbd2/%s",
+			journal->j_devname);
 	if (IS_ERR(t))
 		return PTR_ERR(t);
 
@@ -679,153 +676,6 @@ struct jbd2_stats_proc_session {
 	int max;
 };
 
-static void *jbd2_history_skip_empty(struct jbd2_stats_proc_session *s,
-					struct transaction_stats_s *ts,
-					int first)
-{
-	if (ts == s->stats + s->max)
-		ts = s->stats;
-	if (!first && ts == s->stats + s->start)
-		return NULL;
-	while (ts->ts_type == 0) {
-		ts++;
-		if (ts == s->stats + s->max)
-			ts = s->stats;
-		if (ts == s->stats + s->start)
-			return NULL;
-	}
-	return ts;
-
-}
-
-static void *jbd2_seq_history_start(struct seq_file *seq, loff_t *pos)
-{
-	struct jbd2_stats_proc_session *s = seq->private;
-	struct transaction_stats_s *ts;
-	int l = *pos;
-
-	if (l == 0)
-		return SEQ_START_TOKEN;
-	ts = jbd2_history_skip_empty(s, s->stats + s->start, 1);
-	if (!ts)
-		return NULL;
-	l--;
-	while (l) {
-		ts = jbd2_history_skip_empty(s, ++ts, 0);
-		if (!ts)
-			break;
-		l--;
-	}
-	return ts;
-}
-
-static void *jbd2_seq_history_next(struct seq_file *seq, void *v, loff_t *pos)
-{
-	struct jbd2_stats_proc_session *s = seq->private;
-	struct transaction_stats_s *ts = v;
-
-	++*pos;
-	if (v == SEQ_START_TOKEN)
-		return jbd2_history_skip_empty(s, s->stats + s->start, 1);
-	else
-		return jbd2_history_skip_empty(s, ++ts, 0);
-}
-
-static int jbd2_seq_history_show(struct seq_file *seq, void *v)
-{
-	struct transaction_stats_s *ts = v;
-	if (v == SEQ_START_TOKEN) {
-		seq_printf(seq, "%-4s %-5s %-5s %-5s %-5s %-5s %-5s %-6s %-5s "
-				"%-5s %-5s %-5s %-5s %-5s\n", "R/C", "tid",
-				"wait", "run", "lock", "flush", "log", "hndls",
-				"block", "inlog", "ctime", "write", "drop",
-				"close");
-		return 0;
-	}
-	if (ts->ts_type == JBD2_STATS_RUN)
-		seq_printf(seq, "%-4s %-5lu %-5u %-5u %-5u %-5u %-5u "
-				"%-6lu %-5lu %-5lu\n", "R", ts->ts_tid,
-				jiffies_to_msecs(ts->u.run.rs_wait),
-				jiffies_to_msecs(ts->u.run.rs_running),
-				jiffies_to_msecs(ts->u.run.rs_locked),
-				jiffies_to_msecs(ts->u.run.rs_flushing),
-				jiffies_to_msecs(ts->u.run.rs_logging),
-				ts->u.run.rs_handle_count,
-				ts->u.run.rs_blocks,
-				ts->u.run.rs_blocks_logged);
-	else if (ts->ts_type == JBD2_STATS_CHECKPOINT)
-		seq_printf(seq, "%-4s %-5lu %48s %-5u %-5lu %-5lu %-5lu\n",
-				"C", ts->ts_tid, " ",
-				jiffies_to_msecs(ts->u.chp.cs_chp_time),
-				ts->u.chp.cs_written, ts->u.chp.cs_dropped,
-				ts->u.chp.cs_forced_to_close);
-	else
-		J_ASSERT(0);
-	return 0;
-}
-
-static void jbd2_seq_history_stop(struct seq_file *seq, void *v)
-{
-}
-
-static const struct seq_operations jbd2_seq_history_ops = {
-	.start  = jbd2_seq_history_start,
-	.next   = jbd2_seq_history_next,
-	.stop   = jbd2_seq_history_stop,
-	.show   = jbd2_seq_history_show,
-};
-
-static int jbd2_seq_history_open(struct inode *inode, struct file *file)
-{
-	journal_t *journal = PDE(inode)->data;
-	struct jbd2_stats_proc_session *s;
-	int rc, size;
-
-	s = kmalloc(sizeof(*s), GFP_KERNEL);
-	if (s == NULL)
-		return -ENOMEM;
-	size = sizeof(struct transaction_stats_s) * journal->j_history_max;
-	s->stats = kmalloc(size, GFP_KERNEL);
-	if (s->stats == NULL) {
-		kfree(s);
-		return -ENOMEM;
-	}
-	spin_lock(&journal->j_history_lock);
-	memcpy(s->stats, journal->j_history, size);
-	s->max = journal->j_history_max;
-	s->start = journal->j_history_cur % s->max;
-	spin_unlock(&journal->j_history_lock);
-
-	rc = seq_open(file, &jbd2_seq_history_ops);
-	if (rc == 0) {
-		struct seq_file *m = file->private_data;
-		m->private = s;
-	} else {
-		kfree(s->stats);
-		kfree(s);
-	}
-	return rc;
-
-}
-
-static int jbd2_seq_history_release(struct inode *inode, struct file *file)
-{
-	struct seq_file *seq = file->private_data;
-	struct jbd2_stats_proc_session *s = seq->private;
-
-	kfree(s->stats);
-	kfree(s);
-	return seq_release(inode, file);
-}
-
-static struct file_operations jbd2_seq_history_fops = {
-	.owner		= THIS_MODULE,
-	.open           = jbd2_seq_history_open,
-	.read           = seq_read,
-	.llseek         = seq_lseek,
-	.release        = jbd2_seq_history_release,
-};
-
 static void *jbd2_seq_info_start(struct seq_file *seq, loff_t *pos)
 {
 	return *pos ? NULL : SEQ_START_TOKEN;
@@ -842,29 +692,29 @@ static int jbd2_seq_info_show(struct seq_file *seq, void *v)
 
 	if (v != SEQ_START_TOKEN)
 		return 0;
-	seq_printf(seq, "%lu transaction, each upto %u blocks\n",
+	seq_printf(seq, "%lu transaction, each up to %u blocks\n",
 			s->stats->ts_tid,
 			s->journal->j_max_transaction_buffers);
 	if (s->stats->ts_tid == 0)
 		return 0;
 	seq_printf(seq, "average: \n  %ums waiting for transaction\n",
-	    jiffies_to_msecs(s->stats->u.run.rs_wait / s->stats->ts_tid));
+	    jiffies_to_msecs(s->stats->run.rs_wait / s->stats->ts_tid));
 	seq_printf(seq, "  %ums running transaction\n",
-	    jiffies_to_msecs(s->stats->u.run.rs_running / s->stats->ts_tid));
+	    jiffies_to_msecs(s->stats->run.rs_running / s->stats->ts_tid));
 	seq_printf(seq, "  %ums transaction was being locked\n",
-	    jiffies_to_msecs(s->stats->u.run.rs_locked / s->stats->ts_tid));
+	    jiffies_to_msecs(s->stats->run.rs_locked / s->stats->ts_tid));
 	seq_printf(seq, "  %ums flushing data (in ordered mode)\n",
-	    jiffies_to_msecs(s->stats->u.run.rs_flushing / s->stats->ts_tid));
+	    jiffies_to_msecs(s->stats->run.rs_flushing / s->stats->ts_tid));
 	seq_printf(seq, "  %ums logging transaction\n",
-	    jiffies_to_msecs(s->stats->u.run.rs_logging / s->stats->ts_tid));
+	    jiffies_to_msecs(s->stats->run.rs_logging / s->stats->ts_tid));
 	seq_printf(seq, "  %lluus average transaction commit time\n",
 		   div_u64(s->journal->j_average_commit_time, 1000));
 	seq_printf(seq, "  %lu handles per transaction\n",
-	    s->stats->u.run.rs_handle_count / s->stats->ts_tid);
+	    s->stats->run.rs_handle_count / s->stats->ts_tid);
 	seq_printf(seq, "  %lu blocks per transaction\n",
-	    s->stats->u.run.rs_blocks / s->stats->ts_tid);
+	    s->stats->run.rs_blocks / s->stats->ts_tid);
 	seq_printf(seq, "  %lu logged blocks per transaction\n",
-	    s->stats->u.run.rs_blocks_logged / s->stats->ts_tid);
+	    s->stats->run.rs_blocks_logged / s->stats->ts_tid);
 	return 0;
 }
 
@@ -920,7 +770,7 @@ static int jbd2_seq_info_release(struct inode *inode, struct file *file)
 	return seq_release(inode, file);
 }
 
-static struct file_operations jbd2_seq_info_fops = {
+static const struct file_operations jbd2_seq_info_fops = {
 	.owner		= THIS_MODULE,
 	.open           = jbd2_seq_info_open,
 	.read           = seq_read,
@@ -934,8 +784,6 @@ static void jbd2_stats_proc_init(journal_t *journal)
 {
 	journal->j_proc_entry = proc_mkdir(journal->j_devname, proc_jbd2_stats);
 	if (journal->j_proc_entry) {
-		proc_create_data("history", S_IRUGO, journal->j_proc_entry,
-				 &jbd2_seq_history_fops, journal);
 		proc_create_data("info", S_IRUGO, journal->j_proc_entry,
 				 &jbd2_seq_info_fops, journal);
 	}
@@ -944,27 +792,9 @@ static void jbd2_stats_proc_init(journal_t *journal)
 static void jbd2_stats_proc_exit(journal_t *journal)
 {
 	remove_proc_entry("info", journal->j_proc_entry);
-	remove_proc_entry("history", journal->j_proc_entry);
 	remove_proc_entry(journal->j_devname, proc_jbd2_stats);
 }
 
-static void journal_init_stats(journal_t *journal)
-{
-	int size;
-
-	if (!proc_jbd2_stats)
-		return;
-
-	journal->j_history_max = 100;
-	size = sizeof(struct transaction_stats_s) * journal->j_history_max;
-	journal->j_history = kzalloc(size, GFP_KERNEL);
-	if (!journal->j_history) {
-		journal->j_history_max = 0;
-		return;
-	}
-	spin_lock_init(&journal->j_history_lock);
-}
-
 /*
  * Management for journal control blocks: functions to create and
  * destroy journal_t structures, and to initialise and read existing
@@ -1009,7 +839,7 @@ static journal_t * journal_init_common (void)
 		goto fail;
 	}
 
-	journal_init_stats(journal);
+	spin_lock_init(&journal->j_history_lock);
 
 	return journal;
 fail:
@@ -1115,7 +945,7 @@ journal_t * jbd2_journal_init_inode (struct inode *inode)
 	while ((p = strchr(p, '/')))
 		*p = '!';
 	p = journal->j_devname + strlen(journal->j_devname);
-	sprintf(p, ":%lu", journal->j_inode->i_ino);
+	sprintf(p, "-%lu", journal->j_inode->i_ino);
 	jbd_debug(1,
 		  "journal %p: inode %s/%ld, size %Ld, bits %d, blksize %ld\n",
 		  journal, inode->i_sb->s_id, inode->i_ino,
diff --git a/fs/jfs/super.c b/fs/jfs/super.c
index 37e6dcd..2234c73 100644
--- a/fs/jfs/super.c
+++ b/fs/jfs/super.c
@@ -178,13 +178,11 @@ static void jfs_put_super(struct super_block *sb)
 	rc = jfs_umount(sb);
 	if (rc)
 		jfs_err("jfs_umount failed with return code %d", rc);
-	if (sbi->nls_tab)
-		unload_nls(sbi->nls_tab);
-	sbi->nls_tab = NULL;
+
+	unload_nls(sbi->nls_tab);
 
 	truncate_inode_pages(sbi->direct_inode->i_mapping, 0);
 	iput(sbi->direct_inode);
-	sbi->direct_inode = NULL;
 
 	kfree(sbi);
 
@@ -347,8 +345,7 @@ static int parse_options(char *options, struct super_block *sb, s64 *newLVSize,
 
 	if (nls_map != (void *) -1) {
 		/* Discard old (if remount) */
-		if (sbi->nls_tab)
-			unload_nls(sbi->nls_tab);
+		unload_nls(sbi->nls_tab);
 		sbi->nls_tab = nls_map;
 	}
 	return 1;
diff --git a/fs/libfs.c b/fs/libfs.c
index dcec3d3..219576c 100644
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -527,14 +527,18 @@ ssize_t simple_read_from_buffer(void __user *to, size_t count, loff_t *ppos,
 				const void *from, size_t available)
 {
 	loff_t pos = *ppos;
+	size_t ret;
+
 	if (pos < 0)
 		return -EINVAL;
-	if (pos >= available)
+	if (pos >= available || !count)
 		return 0;
 	if (count > available - pos)
 		count = available - pos;
-	if (copy_to_user(to, from + pos, count))
+	ret = copy_to_user(to, from + pos, count);
+	if (ret == count)
 		return -EFAULT;
+	count -= ret;
 	*ppos = pos + count;
 	return count;
 }
@@ -735,10 +739,11 @@ ssize_t simple_attr_write(struct file *file, const char __user *buf,
 	if (copy_from_user(attr->set_buf, buf, size))
 		goto out;
 
-	ret = len; /* claim we got the whole input */
 	attr->set_buf[size] = '\0';
 	val = simple_strtol(attr->set_buf, NULL, 0);
-	attr->set(attr->data, val);
+	ret = attr->set(attr->data, val);
+	if (ret == 0)
+		ret = len; /* on success, claim we got the whole input */
 out:
 	mutex_unlock(&attr->mutex);
 	return ret;
diff --git a/fs/lockd/xdr.c b/fs/lockd/xdr.c
index 0336f2b..b583ab0 100644
--- a/fs/lockd/xdr.c
+++ b/fs/lockd/xdr.c
@@ -8,7 +8,6 @@
 
 #include <linux/types.h>
 #include <linux/sched.h>
-#include <linux/utsname.h>
 #include <linux/nfs.h>
 
 #include <linux/sunrpc/xdr.h>
diff --git a/fs/lockd/xdr4.c b/fs/lockd/xdr4.c
index e1d5286..ad9dbbc 100644
--- a/fs/lockd/xdr4.c
+++ b/fs/lockd/xdr4.c
@@ -9,7 +9,6 @@
 
 #include <linux/types.h>
 #include <linux/sched.h>
-#include <linux/utsname.h>
 #include <linux/nfs.h>
 
 #include <linux/sunrpc/xdr.h>
diff --git a/fs/namespace.c b/fs/namespace.c
index 7230787..bdc3cb4 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1640,7 +1640,7 @@ static int do_new_mount(struct path *path, char *type, int flags,
 {
 	struct vfsmount *mnt;
 
-	if (!type || !memchr(type, 0, PAGE_SIZE))
+	if (!type)
 		return -EINVAL;
 
 	/* we need capabilities... */
@@ -1871,6 +1871,23 @@ int copy_mount_options(const void __user * data, unsigned long *where)
 	return 0;
 }
 
+int copy_mount_string(const void __user *data, char **where)
+{
+	char *tmp;
+
+	if (!data) {
+		*where = NULL;
+		return 0;
+	}
+
+	tmp = strndup_user(data, PAGE_SIZE);
+	if (IS_ERR(tmp))
+		return PTR_ERR(tmp);
+
+	*where = tmp;
+	return 0;
+}
+
 /*
  * Flags is a 32-bit value that allows up to 31 non-fs dependent flags to
  * be given to the mount() call (ie: read-only, no-dev, no-suid etc).
@@ -1900,8 +1917,6 @@ long do_mount(char *dev_name, char *dir_name, char *type_page,
 
 	if (!dir_name || !*dir_name || !memchr(dir_name, 0, PAGE_SIZE))
 		return -EINVAL;
-	if (dev_name && !memchr(dev_name, 0, PAGE_SIZE))
-		return -EINVAL;
 
 	if (data_page)
 		((char *)data_page)[PAGE_SIZE - 1] = 0;
@@ -2070,40 +2085,42 @@ EXPORT_SYMBOL(create_mnt_ns);
 SYSCALL_DEFINE5(mount, char __user *, dev_name, char __user *, dir_name,
 		char __user *, type, unsigned long, flags, void __user *, data)
 {
-	int retval;
+	int ret;
+	char *kernel_type;
+	char *kernel_dir;
+	char *kernel_dev;
 	unsigned long data_page;
-	unsigned long type_page;
-	unsigned long dev_page;
-	char *dir_page;
 
-	retval = copy_mount_options(type, &type_page);
-	if (retval < 0)
-		return retval;
+	ret = copy_mount_string(type, &kernel_type);
+	if (ret < 0)
+		goto out_type;
 
-	dir_page = getname(dir_name);
-	retval = PTR_ERR(dir_page);
-	if (IS_ERR(dir_page))
-		goto out1;
+	kernel_dir = getname(dir_name);
+	if (IS_ERR(kernel_dir)) {
+		ret = PTR_ERR(kernel_dir);
+		goto out_dir;
+	}
 
-	retval = copy_mount_options(dev_name, &dev_page);
-	if (retval < 0)
-		goto out2;
+	ret = copy_mount_string(dev_name, &kernel_dev);
+	if (ret < 0)
+		goto out_dev;
 
-	retval = copy_mount_options(data, &data_page);
-	if (retval < 0)
-		goto out3;
+	ret = copy_mount_options(data, &data_page);
+	if (ret < 0)
+		goto out_data;
 
-	retval = do_mount((char *)dev_page, dir_page, (char *)type_page,
-			  flags, (void *)data_page);
-	free_page(data_page);
+	ret = do_mount(kernel_dev, kernel_dir, kernel_type, flags,
+		(void *) data_page);
 
-out3:
-	free_page(dev_page);
-out2:
-	putname(dir_page);
-out1:
-	free_page(type_page);
-	return retval;
+	free_page(data_page);
+out_data:
+	kfree(kernel_dev);
+out_dev:
+	putname(kernel_dir);
+out_dir:
+	kfree(kernel_type);
+out_type:
+	return ret;
 }
 
 /*
diff --git a/fs/ncpfs/inode.c b/fs/ncpfs/inode.c
index b99ce20..cf98da1 100644
--- a/fs/ncpfs/inode.c
+++ b/fs/ncpfs/inode.c
@@ -746,16 +746,8 @@ static void ncp_put_super(struct super_block *sb)
 
 #ifdef CONFIG_NCPFS_NLS
 	/* unload the NLS charsets */
-	if (server->nls_vol)
-	{
-		unload_nls(server->nls_vol);
-		server->nls_vol = NULL;
-	}
-	if (server->nls_io)
-	{
-		unload_nls(server->nls_io);
-		server->nls_io = NULL;
-	}
+	unload_nls(server->nls_vol);
+	unload_nls(server->nls_io);
 #endif /* CONFIG_NCPFS_NLS */
 
 	if (server->info_filp)
diff --git a/fs/ncpfs/ioctl.c b/fs/ncpfs/ioctl.c
index 53a7ed7..0d58caf 100644
--- a/fs/ncpfs/ioctl.c
+++ b/fs/ncpfs/ioctl.c
@@ -223,10 +223,8 @@ ncp_set_charsets(struct ncp_server* server, struct ncp_nls_ioctl __user *arg)
 	oldset_io = server->nls_io;
 	server->nls_io = iocharset;
 
-	if (oldset_cp)
-		unload_nls(oldset_cp);
-	if (oldset_io)
-		unload_nls(oldset_io);
+	unload_nls(oldset_cp);
+	unload_nls(oldset_io);
 
 	return 0;
 }
diff --git a/fs/ncpfs/mmap.c b/fs/ncpfs/mmap.c
index 5d8dcb9..15458de 100644
--- a/fs/ncpfs/mmap.c
+++ b/fs/ncpfs/mmap.c
@@ -95,7 +95,7 @@ static int ncp_file_mmap_fault(struct vm_area_struct *area,
 	return VM_FAULT_MAJOR;
 }
 
-static struct vm_operations_struct ncp_file_mmap =
+static const struct vm_operations_struct ncp_file_mmap =
 {
 	.fault = ncp_file_mmap_fault,
 };
diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 1520253..99ea196 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -648,8 +648,6 @@ static int nfs_start_lockd(struct nfs_server *server)
 		.hostname	= clp->cl_hostname,
 		.address	= (struct sockaddr *)&clp->cl_addr,
 		.addrlen	= clp->cl_addrlen,
-		.protocol	= server->flags & NFS_MOUNT_TCP ?
-						IPPROTO_TCP : IPPROTO_UDP,
 		.nfs_version	= clp->rpc_ops->version,
 		.noresvport	= server->flags & NFS_MOUNT_NORESVPORT ?
 					1 : 0,
@@ -660,6 +658,14 @@ static int nfs_start_lockd(struct nfs_server *server)
 	if (server->flags & NFS_MOUNT_NONLM)
 		return 0;
 
+	switch (clp->cl_proto) {
+		default:
+			nlm_init.protocol = IPPROTO_TCP;
+			break;
+		case XPRT_TRANSPORT_UDP:
+			nlm_init.protocol = IPPROTO_UDP;
+	}
+
 	host = nlmclnt_init(&nlm_init);
 	if (IS_ERR(host))
 		return PTR_ERR(host);
@@ -787,7 +793,7 @@ static int nfs_init_server(struct nfs_server *server,
 	dprintk("--> nfs_init_server()\n");
 
 #ifdef CONFIG_NFS_V3
-	if (data->flags & NFS_MOUNT_VER3)
+	if (data->version == 3)
 		cl_init.rpc_ops = &nfs_v3_clientops;
 #endif
 
@@ -964,6 +970,7 @@ static void nfs_server_copy_userdata(struct nfs_server *target, struct nfs_serve
 	target->acdirmin = source->acdirmin;
 	target->acdirmax = source->acdirmax;
 	target->caps = source->caps;
+	target->options = source->options;
 }
 
 /*
@@ -1173,7 +1180,7 @@ static int nfs4_init_client(struct nfs_client *clp,
 				      1, flags & NFS_MOUNT_NORESVPORT);
 	if (error < 0)
 		goto error;
-	memcpy(clp->cl_ipaddr, ip_addr, sizeof(clp->cl_ipaddr));
+	strlcpy(clp->cl_ipaddr, ip_addr, sizeof(clp->cl_ipaddr));
 
 	error = nfs_idmap_new(clp);
 	if (error < 0) {
diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index 5021b75..f5fdd39 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -59,7 +59,7 @@ static int nfs_lock(struct file *filp, int cmd, struct file_lock *fl);
 static int nfs_flock(struct file *filp, int cmd, struct file_lock *fl);
 static int nfs_setlease(struct file *file, long arg, struct file_lock **fl);
 
-static struct vm_operations_struct nfs_file_vm_ops;
+static const struct vm_operations_struct nfs_file_vm_ops;
 
 const struct file_operations nfs_file_operations = {
 	.llseek		= nfs_file_llseek,
@@ -525,6 +525,7 @@ const struct address_space_operations nfs_file_aops = {
 	.direct_IO = nfs_direct_IO,
 	.migratepage = nfs_migrate_page,
 	.launder_page = nfs_launder_page,
+	.error_remove_page = generic_error_remove_page,
 };
 
 /*
@@ -571,7 +572,7 @@ out_unlock:
 	return VM_FAULT_SIGBUS;
 }
 
-static struct vm_operations_struct nfs_file_vm_ops = {
+static const struct vm_operations_struct nfs_file_vm_ops = {
 	.fault = filemap_fault,
 	.page_mkwrite = nfs_vm_page_mkwrite,
 };
diff --git a/fs/nfs/fscache.c b/fs/nfs/fscache.c
index 379be67..70fad69 100644
--- a/fs/nfs/fscache.c
+++ b/fs/nfs/fscache.c
@@ -58,17 +58,34 @@ void nfs_fscache_release_client_cookie(struct nfs_client *clp)
 /*
  * Get the cache cookie for an NFS superblock.  We have to handle
  * uniquification here because the cache doesn't do it for us.
+ *
+ * The default uniquifier is just an empty string, but it may be overridden
+ * either by the 'fsc=xxx' option to mount, or by inheriting it from the parent
+ * superblock across an automount point of some nature.
  */
-void nfs_fscache_get_super_cookie(struct super_block *sb,
-				  struct nfs_parsed_mount_data *data)
+void nfs_fscache_get_super_cookie(struct super_block *sb, const char *uniq,
+				  struct nfs_clone_mount *mntdata)
 {
 	struct nfs_fscache_key *key, *xkey;
 	struct nfs_server *nfss = NFS_SB(sb);
 	struct rb_node **p, *parent;
-	const char *uniq = data->fscache_uniq ?: "";
 	int diff, ulen;
 
-	ulen = strlen(uniq);
+	if (uniq) {
+		ulen = strlen(uniq);
+	} else if (mntdata) {
+		struct nfs_server *mnt_s = NFS_SB(mntdata->sb);
+		if (mnt_s->fscache_key) {
+			uniq = mnt_s->fscache_key->key.uniquifier;
+			ulen = mnt_s->fscache_key->key.uniq_len;
+		}
+	}
+
+	if (!uniq) {
+		uniq = "";
+		ulen = 1;
+	}
+
 	key = kzalloc(sizeof(*key) + ulen, GFP_KERNEL);
 	if (!key)
 		return;
diff --git a/fs/nfs/fscache.h b/fs/nfs/fscache.h
index 6e809bb..b9c572d 100644
--- a/fs/nfs/fscache.h
+++ b/fs/nfs/fscache.h
@@ -74,7 +74,8 @@ extern void nfs_fscache_get_client_cookie(struct nfs_client *);
 extern void nfs_fscache_release_client_cookie(struct nfs_client *);
 
 extern void nfs_fscache_get_super_cookie(struct super_block *,
-					 struct nfs_parsed_mount_data *);
+					 const char *,
+					 struct nfs_clone_mount *);
 extern void nfs_fscache_release_super_cookie(struct super_block *);
 
 extern void nfs_fscache_init_inode_cookie(struct inode *);
@@ -173,7 +174,8 @@ static inline void nfs_fscache_release_client_cookie(struct nfs_client *clp) {}
 
 static inline void nfs_fscache_get_super_cookie(
 	struct super_block *sb,
-	struct nfs_parsed_mount_data *data)
+	const char *uniq,
+	struct nfs_clone_mount *mntdata)
 {
 }
 static inline void nfs_fscache_release_super_cookie(struct super_block *sb) {}
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 060022b..faa0918 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -458,49 +458,21 @@ nfs_setattr(struct dentry *dentry, struct iattr *attr)
  */
 static int nfs_vmtruncate(struct inode * inode, loff_t offset)
 {
-	if (i_size_read(inode) < offset) {
-		unsigned long limit;
-
-		limit = current->signal->rlim[RLIMIT_FSIZE].rlim_cur;
-		if (limit != RLIM_INFINITY && offset > limit)
-			goto out_sig;
-		if (offset > inode->i_sb->s_maxbytes)
-			goto out_big;
-		spin_lock(&inode->i_lock);
-		i_size_write(inode, offset);
-		spin_unlock(&inode->i_lock);
-	} else {
-		struct address_space *mapping = inode->i_mapping;
+	loff_t oldsize;
+	int err;
 
-		/*
-		 * truncation of in-use swapfiles is disallowed - it would
-		 * cause subsequent swapout to scribble on the now-freed
-		 * blocks.
-		 */
-		if (IS_SWAPFILE(inode))
-			return -ETXTBSY;
-		spin_lock(&inode->i_lock);
-		i_size_write(inode, offset);
-		spin_unlock(&inode->i_lock);
+	err = inode_newsize_ok(inode, offset);
+	if (err)
+		goto out;
 
-		/*
-		 * unmap_mapping_range is called twice, first simply for
-		 * efficiency so that truncate_inode_pages does fewer
-		 * single-page unmaps.  However after this first call, and
-		 * before truncate_inode_pages finishes, it is possible for
-		 * private pages to be COWed, which remain after
-		 * truncate_inode_pages finishes, hence the second
-		 * unmap_mapping_range call must be made for correctness.
-		 */
-		unmap_mapping_range(mapping, offset + PAGE_SIZE - 1, 0, 1);
-		truncate_inode_pages(mapping, offset);
-		unmap_mapping_range(mapping, offset + PAGE_SIZE - 1, 0, 1);
-	}
-	return 0;
-out_sig:
-	send_sig(SIGXFSZ, current, 0);
-out_big:
-	return -EFBIG;
+	spin_lock(&inode->i_lock);
+	oldsize = inode->i_size;
+	i_size_write(inode, offset);
+	spin_unlock(&inode->i_lock);
+
+	truncate_pagecache(inode, oldsize, offset);
+out:
+	return err;
 }
 
 /**
diff --git a/fs/nfs/nfs2xdr.c b/fs/nfs/nfs2xdr.c
index c862c93..5e078b2 100644
--- a/fs/nfs/nfs2xdr.c
+++ b/fs/nfs/nfs2xdr.c
@@ -13,7 +13,6 @@
 #include <linux/time.h>
 #include <linux/mm.h>
 #include <linux/slab.h>
-#include <linux/utsname.h>
 #include <linux/errno.h>
 #include <linux/string.h>
 #include <linux/in.h>
diff --git a/fs/nfs/nfs3proc.c b/fs/nfs/nfs3proc.c
index ee6a13f..3f8881d 100644
--- a/fs/nfs/nfs3proc.c
+++ b/fs/nfs/nfs3proc.c
@@ -7,7 +7,6 @@
  */
 
 #include <linux/mm.h>
-#include <linux/utsname.h>
 #include <linux/errno.h>
 #include <linux/string.h>
 #include <linux/sunrpc/clnt.h>
diff --git a/fs/nfs/nfs3xdr.c b/fs/nfs/nfs3xdr.c
index 35869a4..5fe5492 100644
--- a/fs/nfs/nfs3xdr.c
+++ b/fs/nfs/nfs3xdr.c
@@ -10,7 +10,6 @@
 #include <linux/time.h>
 #include <linux/mm.h>
 #include <linux/slab.h>
-#include <linux/utsname.h>
 #include <linux/errno.h>
 #include <linux/string.h>
 #include <linux/in.h>
diff --git a/fs/nfs/nfs4namespace.c b/fs/nfs/nfs4namespace.c
index 2636c26..fa3408f 100644
--- a/fs/nfs/nfs4namespace.c
+++ b/fs/nfs/nfs4namespace.c
@@ -121,7 +121,7 @@ static struct vfsmount *try_location(struct nfs_clone_mount *mountdata,
 
 	mnt_path = nfs4_pathname_string(&location->rootpath, page2, PAGE_SIZE);
 	if (IS_ERR(mnt_path))
-		return mnt;
+		return ERR_CAST(mnt_path);
 	mountdata->mnt_path = mnt_path;
 	maxbuflen = mnt_path - 1 - page2;
 
@@ -132,15 +132,15 @@ static struct vfsmount *try_location(struct nfs_clone_mount *mountdata,
 		if (buf->len <= 0 || buf->len >= maxbuflen)
 			continue;
 
-		mountdata->addr = (struct sockaddr *)&addr;
-
 		if (memchr(buf->data, IPV6_SCOPE_DELIMITER, buf->len))
 			continue;
-		mountdata->addrlen = nfs_parse_server_name(buf->data,
-				buf->len,
-				mountdata->addr, mountdata->addrlen);
+
+		mountdata->addrlen = nfs_parse_server_name(buf->data, buf->len,
+				(struct sockaddr *)&addr, sizeof(addr));
 		if (mountdata->addrlen == 0)
 			continue;
+
+		mountdata->addr = (struct sockaddr *)&addr;
 		rpc_set_port(mountdata->addr, NFS_PORT);
 
 		memcpy(page2, buf->data, buf->len);
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index be6544a..ed7c269 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -36,7 +36,6 @@
  */
 
 #include <linux/mm.h>
-#include <linux/utsname.h>
 #include <linux/delay.h>
 #include <linux/errno.h>
 #include <linux/string.h>
diff --git a/fs/nfs/nfs4renewd.c b/fs/nfs/nfs4renewd.c
index e27c6ce..0156c01 100644
--- a/fs/nfs/nfs4renewd.c
+++ b/fs/nfs/nfs4renewd.c
@@ -127,12 +127,6 @@ nfs4_schedule_state_renewal(struct nfs_client *clp)
 }
 
 void
-nfs4_renewd_prepare_shutdown(struct nfs_server *server)
-{
-	cancel_delayed_work(&server->nfs_client->cl_renewd);
-}
-
-void
 nfs4_kill_renewd(struct nfs_client *clp)
 {
 	cancel_delayed_work_sync(&clp->cl_renewd);
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index cfc30d3..83ad47c 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -39,7 +39,6 @@
 #include <linux/time.h>
 #include <linux/mm.h>
 #include <linux/slab.h>
-#include <linux/utsname.h>
 #include <linux/errno.h>
 #include <linux/string.h>
 #include <linux/in.h>
diff --git a/fs/nfs/proc.c b/fs/nfs/proc.c
index 7be72d9..ef58385 100644
--- a/fs/nfs/proc.c
+++ b/fs/nfs/proc.c
@@ -32,7 +32,6 @@
 #include <linux/slab.h>
 #include <linux/time.h>
 #include <linux/mm.h>
-#include <linux/utsname.h>
 #include <linux/errno.h>
 #include <linux/string.h>
 #include <linux/in.h>
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index f1cc058..a2c18ac 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -728,6 +728,29 @@ static void nfs_umount_begin(struct super_block *sb)
 	unlock_kernel();
 }
 
+static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(unsigned int version)
+{
+	struct nfs_parsed_mount_data *data;
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (data) {
+		data->rsize		= NFS_MAX_FILE_IO_SIZE;
+		data->wsize		= NFS_MAX_FILE_IO_SIZE;
+		data->acregmin		= NFS_DEF_ACREGMIN;
+		data->acregmax		= NFS_DEF_ACREGMAX;
+		data->acdirmin		= NFS_DEF_ACDIRMIN;
+		data->acdirmax		= NFS_DEF_ACDIRMAX;
+		data->mount_server.port	= NFS_UNSPEC_PORT;
+		data->nfs_server.port	= NFS_UNSPEC_PORT;
+		data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
+		data->auth_flavors[0]	= RPC_AUTH_UNIX;
+		data->auth_flavor_len	= 1;
+		data->version		= version;
+		data->minorversion	= 0;
+	}
+	return data;
+}
+
 /*
  * Sanity-check a server address provided by the mount command.
  *
@@ -755,15 +778,13 @@ static int nfs_verify_server_address(struct sockaddr *addr)
  * Select between a default port value and a user-specified port value.
  * If a zero value is set, then autobind will be used.
  */
-static void nfs_set_default_port(struct sockaddr *sap, const int parsed_port,
+static void nfs_set_port(struct sockaddr *sap, int *port,
 				 const unsigned short default_port)
 {
-	unsigned short port = default_port;
-
-	if (parsed_port != NFS_UNSPEC_PORT)
-		port = parsed_port;
+	if (*port == NFS_UNSPEC_PORT)
+		*port = default_port;
 
-	rpc_set_port(sap, port);
+	rpc_set_port(sap, *port);
 }
 
 /*
@@ -1430,10 +1451,13 @@ static int nfs_try_mount(struct nfs_parsed_mount_data *args,
 	int status;
 
 	if (args->mount_server.version == 0) {
-		if (args->flags & NFS_MOUNT_VER3)
-			args->mount_server.version = NFS_MNT3_VERSION;
-		else
-			args->mount_server.version = NFS_MNT_VERSION;
+		switch (args->version) {
+			default:
+				args->mount_server.version = NFS_MNT3_VERSION;
+				break;
+			case 2:
+				args->mount_server.version = NFS_MNT_VERSION;
+		}
 	}
 	request.version = args->mount_server.version;
 
@@ -1451,7 +1475,7 @@ static int nfs_try_mount(struct nfs_parsed_mount_data *args,
 		args->mount_server.addrlen = args->nfs_server.addrlen;
 	}
 	request.salen = args->mount_server.addrlen;
-	nfs_set_default_port(request.sap, args->mount_server.port, 0);
+	nfs_set_port(request.sap, &args->mount_server.port, 0);
 
 	/*
 	 * Now ask the mount server to map our export path
@@ -1634,20 +1658,6 @@ static int nfs_validate_mount_data(void *options,
 	if (data == NULL)
 		goto out_no_data;
 
-	args->flags		= (NFS_MOUNT_VER3 | NFS_MOUNT_TCP);
-	args->rsize		= NFS_MAX_FILE_IO_SIZE;
-	args->wsize		= NFS_MAX_FILE_IO_SIZE;
-	args->acregmin		= NFS_DEF_ACREGMIN;
-	args->acregmax		= NFS_DEF_ACREGMAX;
-	args->acdirmin		= NFS_DEF_ACDIRMIN;
-	args->acdirmax		= NFS_DEF_ACDIRMAX;
-	args->mount_server.port	= NFS_UNSPEC_PORT;
-	args->nfs_server.port	= NFS_UNSPEC_PORT;
-	args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
-	args->auth_flavors[0]	= RPC_AUTH_UNIX;
-	args->auth_flavor_len	= 1;
-	args->minorversion	= 0;
-
 	switch (data->version) {
 	case 1:
 		data->namlen = 0;
@@ -1755,7 +1765,7 @@ static int nfs_validate_mount_data(void *options,
 			goto out_v4_not_compiled;
 #endif
 
-		nfs_set_default_port(sap, args->nfs_server.port, 0);
+		nfs_set_port(sap, &args->nfs_server.port, 0);
 
 		nfs_set_mount_transport_protocol(args);
 
@@ -1778,7 +1788,7 @@ static int nfs_validate_mount_data(void *options,
 	}
 
 #ifndef CONFIG_NFS_V3
-	if (args->flags & NFS_MOUNT_VER3)
+	if (args->version == 3)
 		goto out_v3_not_compiled;
 #endif /* !CONFIG_NFS_V3 */
 
@@ -1836,9 +1846,10 @@ nfs_compare_remount_data(struct nfs_server *nfss,
 	    data->acdirmin != nfss->acdirmin / HZ ||
 	    data->acdirmax != nfss->acdirmax / HZ ||
 	    data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
+	    data->nfs_server.port != nfss->port ||
 	    data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
-	    memcmp(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
-		   data->nfs_server.addrlen) != 0)
+	    !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
+			  (struct sockaddr *)&nfss->nfs_client->cl_addr))
 		return -EINVAL;
 
 	return 0;
@@ -1881,6 +1892,7 @@ nfs_remount(struct super_block *sb, int *flags, char *raw_data)
 	data->acdirmin = nfss->acdirmin / HZ;
 	data->acdirmax = nfss->acdirmax / HZ;
 	data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
+	data->nfs_server.port = nfss->port;
 	data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
 	memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
 		data->nfs_server.addrlen);
@@ -1936,7 +1948,7 @@ static void nfs_fill_super(struct super_block *sb,
 	if (data->bsize)
 		sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
 
-	if (server->flags & NFS_MOUNT_VER3) {
+	if (server->nfs_client->rpc_ops->version == 3) {
 		/* The VFS shouldn't apply the umask to mode bits. We will do
 		 * so ourselves when necessary.
 		 */
@@ -1960,7 +1972,7 @@ static void nfs_clone_super(struct super_block *sb,
 	sb->s_blocksize = old_sb->s_blocksize;
 	sb->s_maxbytes = old_sb->s_maxbytes;
 
-	if (server->flags & NFS_MOUNT_VER3) {
+	if (server->nfs_client->rpc_ops->version == 3) {
 		/* The VFS shouldn't apply the umask to mode bits. We will do
 		 * so ourselves when necessary.
 		 */
@@ -2094,7 +2106,7 @@ static int nfs_get_sb(struct file_system_type *fs_type,
 	};
 	int error = -ENOMEM;
 
-	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	data = nfs_alloc_parsed_mount_data(3);
 	mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
 	if (data == NULL || mntfh == NULL)
 		goto out_free_fh;
@@ -2144,7 +2156,8 @@ static int nfs_get_sb(struct file_system_type *fs_type,
 	if (!s->s_root) {
 		/* initial superblock/root creation */
 		nfs_fill_super(s, data);
-		nfs_fscache_get_super_cookie(s, data);
+		nfs_fscache_get_super_cookie(
+			s, data ? data->fscache_uniq : NULL, NULL);
 	}
 
 	mntroot = nfs_get_root(s, mntfh);
@@ -2245,6 +2258,7 @@ static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags,
 	if (!s->s_root) {
 		/* initial superblock/root creation */
 		nfs_clone_super(s, data->sb);
+		nfs_fscache_get_super_cookie(s, NULL, data);
 	}
 
 	mntroot = nfs_get_root(s, data->fh);
@@ -2317,7 +2331,7 @@ static int nfs4_validate_text_mount_data(void *options,
 {
 	struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
 
-	nfs_set_default_port(sap, args->nfs_server.port, NFS_PORT);
+	nfs_set_port(sap, &args->nfs_server.port, NFS_PORT);
 
 	nfs_validate_transport_protocol(args);
 
@@ -2362,18 +2376,6 @@ static int nfs4_validate_mount_data(void *options,
 	if (data == NULL)
 		goto out_no_data;
 
-	args->rsize		= NFS_MAX_FILE_IO_SIZE;
-	args->wsize		= NFS_MAX_FILE_IO_SIZE;
-	args->acregmin		= NFS_DEF_ACREGMIN;
-	args->acregmax		= NFS_DEF_ACREGMAX;
-	args->acdirmin		= NFS_DEF_ACDIRMIN;
-	args->acdirmax		= NFS_DEF_ACDIRMAX;
-	args->nfs_server.port	= NFS_UNSPEC_PORT;
-	args->auth_flavors[0]	= RPC_AUTH_UNIX;
-	args->auth_flavor_len	= 1;
-	args->version		= 4;
-	args->minorversion	= 0;
-
 	switch (data->version) {
 	case 1:
 		if (data->host_addrlen > sizeof(args->nfs_server.address))
@@ -2508,7 +2510,8 @@ static int nfs4_remote_get_sb(struct file_system_type *fs_type,
 	if (!s->s_root) {
 		/* initial superblock/root creation */
 		nfs4_fill_super(s);
-		nfs_fscache_get_super_cookie(s, data);
+		nfs_fscache_get_super_cookie(
+			s, data ? data->fscache_uniq : NULL, NULL);
 	}
 
 	mntroot = nfs4_get_root(s, mntfh);
@@ -2656,7 +2659,7 @@ static int nfs4_get_sb(struct file_system_type *fs_type,
 	struct nfs_parsed_mount_data *data;
 	int error = -ENOMEM;
 
-	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	data = nfs_alloc_parsed_mount_data(4);
 	if (data == NULL)
 		goto out_free_data;
 
@@ -2686,7 +2689,6 @@ static void nfs4_kill_super(struct super_block *sb)
 	dprintk("--> %s\n", __func__);
 	nfs_super_return_all_delegations(sb);
 	kill_anon_super(sb);
-	nfs4_renewd_prepare_shutdown(server);
 	nfs_fscache_release_super_cookie(sb);
 	nfs_free_server(server);
 	dprintk("<-- %s\n", __func__);
@@ -2741,6 +2743,7 @@ static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags,
 	if (!s->s_root) {
 		/* initial superblock/root creation */
 		nfs4_clone_super(s, data->sb);
+		nfs_fscache_get_super_cookie(s, NULL, data);
 	}
 
 	mntroot = nfs4_get_root(s, data->fh);
@@ -2822,6 +2825,7 @@ static int nfs4_remote_referral_get_sb(struct file_system_type *fs_type,
 	if (!s->s_root) {
 		/* initial superblock/root creation */
 		nfs4_fill_super(s);
+		nfs_fscache_get_super_cookie(s, NULL, data);
 	}
 
 	mntroot = nfs4_get_root(s, &mntfh);
diff --git a/fs/nfsd/nfs4idmap.c b/fs/nfsd/nfs4idmap.c
index cdfa86f..ba2c199 100644
--- a/fs/nfsd/nfs4idmap.c
+++ b/fs/nfsd/nfs4idmap.c
@@ -38,7 +38,6 @@
 #include <linux/init.h>
 
 #include <linux/mm.h>
-#include <linux/utsname.h>
 #include <linux/errno.h>
 #include <linux/string.h>
 #include <linux/sunrpc/clnt.h>
diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
index 00388d2..5c01fc1 100644
--- a/fs/nfsd/nfsctl.c
+++ b/fs/nfsd/nfsctl.c
@@ -176,7 +176,7 @@ static const struct file_operations exports_operations = {
 extern int nfsd_pool_stats_open(struct inode *inode, struct file *file);
 extern int nfsd_pool_stats_release(struct inode *inode, struct file *file);
 
-static struct file_operations pool_stats_operations = {
+static const struct file_operations pool_stats_operations = {
 	.open		= nfsd_pool_stats_open,
 	.read		= seq_read,
 	.llseek		= seq_lseek,
diff --git a/fs/nilfs2/btnode.c b/fs/nilfs2/btnode.c
index 6a2711f..5941958 100644
--- a/fs/nilfs2/btnode.c
+++ b/fs/nilfs2/btnode.c
@@ -36,6 +36,7 @@
 
 void nilfs_btnode_cache_init_once(struct address_space *btnc)
 {
+	memset(btnc, 0, sizeof(*btnc));
 	INIT_RADIX_TREE(&btnc->page_tree, GFP_ATOMIC);
 	spin_lock_init(&btnc->tree_lock);
 	INIT_LIST_HEAD(&btnc->private_list);
diff --git a/fs/nilfs2/dir.c b/fs/nilfs2/dir.c
index 1a4fa04..e097099 100644
--- a/fs/nilfs2/dir.c
+++ b/fs/nilfs2/dir.c
@@ -697,7 +697,7 @@ not_empty:
 	return 0;
 }
 
-struct file_operations nilfs_dir_operations = {
+const struct file_operations nilfs_dir_operations = {
 	.llseek		= generic_file_llseek,
 	.read		= generic_read_dir,
 	.readdir	= nilfs_readdir,
diff --git a/fs/nilfs2/file.c b/fs/nilfs2/file.c
index fc8278c..30292df 100644
--- a/fs/nilfs2/file.c
+++ b/fs/nilfs2/file.c
@@ -117,7 +117,7 @@ static int nilfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
 	return 0;
 }
 
-struct vm_operations_struct nilfs_file_vm_ops = {
+static const struct vm_operations_struct nilfs_file_vm_ops = {
 	.fault		= filemap_fault,
 	.page_mkwrite	= nilfs_page_mkwrite,
 };
@@ -134,7 +134,7 @@ static int nilfs_file_mmap(struct file *file, struct vm_area_struct *vma)
  * We have mostly NULL's here: the current defaults are ok for
  * the nilfs filesystem.
  */
-struct file_operations nilfs_file_operations = {
+const struct file_operations nilfs_file_operations = {
 	.llseek		= generic_file_llseek,
 	.read		= do_sync_read,
 	.write		= do_sync_write,
diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c
index 2d2c501..5040220 100644
--- a/fs/nilfs2/inode.c
+++ b/fs/nilfs2/inode.c
@@ -400,6 +400,7 @@ int nilfs_read_inode_common(struct inode *inode,
 	ii->i_dir_acl = S_ISREG(inode->i_mode) ?
 		0 : le32_to_cpu(raw_inode->i_dir_acl);
 #endif
+	ii->i_dir_start_lookup = 0;
 	ii->i_cno = 0;
 	inode->i_generation = le32_to_cpu(raw_inode->i_generation);
 
diff --git a/fs/nilfs2/mdt.c b/fs/nilfs2/mdt.c
index b18c499..f632611 100644
--- a/fs/nilfs2/mdt.c
+++ b/fs/nilfs2/mdt.c
@@ -433,7 +433,7 @@ static const struct address_space_operations def_mdt_aops = {
 };
 
 static const struct inode_operations def_mdt_iops;
-static struct file_operations def_mdt_fops;
+static const struct file_operations def_mdt_fops;
 
 /*
  * NILFS2 uses pseudo inodes for meta data files such as DAT, cpfile, sufile,
diff --git a/fs/nilfs2/nilfs.h b/fs/nilfs2/nilfs.h
index bad7368..4da6f67 100644
--- a/fs/nilfs2/nilfs.h
+++ b/fs/nilfs2/nilfs.h
@@ -294,9 +294,9 @@ void nilfs_clear_gcdat_inode(struct the_nilfs *);
 /*
  * Inodes and files operations
  */
-extern struct file_operations nilfs_dir_operations;
+extern const struct file_operations nilfs_dir_operations;
 extern const struct inode_operations nilfs_file_inode_operations;
-extern struct file_operations nilfs_file_operations;
+extern const struct file_operations nilfs_file_operations;
 extern const struct address_space_operations nilfs_aops;
 extern const struct inode_operations nilfs_dir_inode_operations;
 extern const struct inode_operations nilfs_special_inode_operations;
diff --git a/fs/nls/nls_base.c b/fs/nls/nls_base.c
index 477d37d..44a88a9 100644
--- a/fs/nls/nls_base.c
+++ b/fs/nls/nls_base.c
@@ -124,10 +124,10 @@ int utf8s_to_utf16s(const u8 *s, int len, wchar_t *pwcs)
 	while (*s && len > 0) {
 		if (*s & 0x80) {
 			size = utf8_to_utf32(s, len, &u);
-			if (size < 0) {
-				/* Ignore character and move on */
-				size = 1;
-			} else if (u >= PLANE_SIZE) {
+			if (size < 0)
+				return -EINVAL;
+
+			if (u >= PLANE_SIZE) {
 				u -= PLANE_SIZE;
 				*op++ = (wchar_t) (SURROGATE_PAIR |
 						((u >> 10) & SURROGATE_BITS));
@@ -270,7 +270,8 @@ struct nls_table *load_nls(char *charset)
 
 void unload_nls(struct nls_table *nls)
 {
-	module_put(nls->owner);
+	if (nls)
+		module_put(nls->owner);
 }
 
 static const wchar_t charset2uni[256] = {
diff --git a/fs/ntfs/aops.c b/fs/ntfs/aops.c
index b38f944..cfce53c 100644
--- a/fs/ntfs/aops.c
+++ b/fs/ntfs/aops.c
@@ -1550,6 +1550,7 @@ const struct address_space_operations ntfs_aops = {
 	.migratepage	= buffer_migrate_page,	/* Move a page cache page from
 						   one physical page to an
 						   other. */
+	.error_remove_page = generic_error_remove_page,
 };
 
 /**
@@ -1569,6 +1570,7 @@ const struct address_space_operations ntfs_mst_aops = {
 	.migratepage	= buffer_migrate_page,	/* Move a page cache page from
 						   one physical page to an
 						   other. */
+	.error_remove_page = generic_error_remove_page,
 };
 
 #ifdef NTFS_RW
diff --git a/fs/ntfs/super.c b/fs/ntfs/super.c
index abaaa1c..80b0477 100644
--- a/fs/ntfs/super.c
+++ b/fs/ntfs/super.c
@@ -201,8 +201,7 @@ use_utf8:
 						v, old_nls->charset);
 				nls_map = old_nls;
 			} else /* nls_map */ {
-				if (old_nls)
-					unload_nls(old_nls);
+				unload_nls(old_nls);
 			}
 		} else if (!strcmp(p, "utf8")) {
 			bool val = false;
@@ -2427,10 +2426,9 @@ static void ntfs_put_super(struct super_block *sb)
 		ntfs_free(vol->upcase);
 		vol->upcase = NULL;
 	}
-	if (vol->nls_map) {
-		unload_nls(vol->nls_map);
-		vol->nls_map = NULL;
-	}
+
+	unload_nls(vol->nls_map);
+
 	sb->s_fs_info = NULL;
 	kfree(vol);
 
diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index 72e7606..deb2b13 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -2022,4 +2022,5 @@ const struct address_space_operations ocfs2_aops = {
 	.releasepage		= ocfs2_releasepage,
 	.migratepage		= buffer_migrate_page,
 	.is_partially_uptodate	= block_is_partially_uptodate,
+	.error_remove_page	= generic_error_remove_page,
 };
diff --git a/fs/ocfs2/cluster/heartbeat.c b/fs/ocfs2/cluster/heartbeat.c
index 09cc25d..c452d11 100644
--- a/fs/ocfs2/cluster/heartbeat.c
+++ b/fs/ocfs2/cluster/heartbeat.c
@@ -966,7 +966,7 @@ static ssize_t o2hb_debug_read(struct file *file, char __user *buf,
 }
 #endif  /* CONFIG_DEBUG_FS */
 
-static struct file_operations o2hb_debug_fops = {
+static const struct file_operations o2hb_debug_fops = {
 	.open =		o2hb_debug_open,
 	.release =	o2hb_debug_release,
 	.read =		o2hb_debug_read,
diff --git a/fs/ocfs2/cluster/netdebug.c b/fs/ocfs2/cluster/netdebug.c
index cfb2be7..da794bc 100644
--- a/fs/ocfs2/cluster/netdebug.c
+++ b/fs/ocfs2/cluster/netdebug.c
@@ -207,7 +207,7 @@ static int nst_fop_release(struct inode *inode, struct file *file)
 	return seq_release_private(inode, file);
 }
 
-static struct file_operations nst_seq_fops = {
+static const struct file_operations nst_seq_fops = {
 	.open = nst_fop_open,
 	.read = seq_read,
 	.llseek = seq_lseek,
@@ -388,7 +388,7 @@ static int sc_fop_release(struct inode *inode, struct file *file)
 	return seq_release_private(inode, file);
 }
 
-static struct file_operations sc_seq_fops = {
+static const struct file_operations sc_seq_fops = {
 	.open = sc_fop_open,
 	.read = seq_read,
 	.llseek = seq_lseek,
diff --git a/fs/ocfs2/dlm/dlmast.c b/fs/ocfs2/dlm/dlmast.c
index 81eff8e..01cf8cc 100644
--- a/fs/ocfs2/dlm/dlmast.c
+++ b/fs/ocfs2/dlm/dlmast.c
@@ -30,7 +30,6 @@
 #include <linux/types.h>
 #include <linux/slab.h>
 #include <linux/highmem.h>
-#include <linux/utsname.h>
 #include <linux/init.h>
 #include <linux/sysctl.h>
 #include <linux/random.h>
diff --git a/fs/ocfs2/dlm/dlmconvert.c b/fs/ocfs2/dlm/dlmconvert.c
index 75997b4..ca96bce 100644
--- a/fs/ocfs2/dlm/dlmconvert.c
+++ b/fs/ocfs2/dlm/dlmconvert.c
@@ -30,7 +30,6 @@
 #include <linux/types.h>
 #include <linux/slab.h>
 #include <linux/highmem.h>
-#include <linux/utsname.h>
 #include <linux/init.h>
 #include <linux/sysctl.h>
 #include <linux/random.h>
diff --git a/fs/ocfs2/dlm/dlmdebug.c b/fs/ocfs2/dlm/dlmdebug.c
index c5c8812..42b0bad 100644
--- a/fs/ocfs2/dlm/dlmdebug.c
+++ b/fs/ocfs2/dlm/dlmdebug.c
@@ -27,7 +27,6 @@
 #include <linux/types.h>
 #include <linux/slab.h>
 #include <linux/highmem.h>
-#include <linux/utsname.h>
 #include <linux/sysctl.h>
 #include <linux/spinlock.h>
 #include <linux/debugfs.h>
@@ -479,7 +478,7 @@ bail:
 	return -ENOMEM;
 }
 
-static struct file_operations debug_purgelist_fops = {
+static const struct file_operations debug_purgelist_fops = {
 	.open =		debug_purgelist_open,
 	.release =	debug_buffer_release,
 	.read =		debug_buffer_read,
@@ -539,7 +538,7 @@ bail:
 	return -ENOMEM;
 }
 
-static struct file_operations debug_mle_fops = {
+static const struct file_operations debug_mle_fops = {
 	.open =		debug_mle_open,
 	.release =	debug_buffer_release,
 	.read =		debug_buffer_read,
@@ -742,7 +741,7 @@ static int debug_lockres_release(struct inode *inode, struct file *file)
 	return seq_release_private(inode, file);
 }
 
-static struct file_operations debug_lockres_fops = {
+static const struct file_operations debug_lockres_fops = {
 	.open =		debug_lockres_open,
 	.release =	debug_lockres_release,
 	.read =		seq_read,
@@ -926,7 +925,7 @@ bail:
 	return -ENOMEM;
 }
 
-static struct file_operations debug_state_fops = {
+static const struct file_operations debug_state_fops = {
 	.open =		debug_state_open,
 	.release =	debug_buffer_release,
 	.read =		debug_buffer_read,
diff --git a/fs/ocfs2/dlm/dlmdomain.c b/fs/ocfs2/dlm/dlmdomain.c
index 4d9e6b2..0334000 100644
--- a/fs/ocfs2/dlm/dlmdomain.c
+++ b/fs/ocfs2/dlm/dlmdomain.c
@@ -28,7 +28,6 @@
 #include <linux/types.h>
 #include <linux/slab.h>
 #include <linux/highmem.h>
-#include <linux/utsname.h>
 #include <linux/init.h>
 #include <linux/spinlock.h>
 #include <linux/delay.h>
diff --git a/fs/ocfs2/dlm/dlmlock.c b/fs/ocfs2/dlm/dlmlock.c
index 83a9f29..437698e 100644
--- a/fs/ocfs2/dlm/dlmlock.c
+++ b/fs/ocfs2/dlm/dlmlock.c
@@ -30,7 +30,6 @@
 #include <linux/types.h>
 #include <linux/slab.h>
 #include <linux/highmem.h>
-#include <linux/utsname.h>
 #include <linux/init.h>
 #include <linux/sysctl.h>
 #include <linux/random.h>
diff --git a/fs/ocfs2/dlm/dlmmaster.c b/fs/ocfs2/dlm/dlmmaster.c
index f8b653f..83bcaf2 100644
--- a/fs/ocfs2/dlm/dlmmaster.c
+++ b/fs/ocfs2/dlm/dlmmaster.c
@@ -30,7 +30,6 @@
 #include <linux/types.h>
 #include <linux/slab.h>
 #include <linux/highmem.h>
-#include <linux/utsname.h>
 #include <linux/init.h>
 #include <linux/sysctl.h>
 #include <linux/random.h>
diff --git a/fs/ocfs2/dlm/dlmrecovery.c b/fs/ocfs2/dlm/dlmrecovery.c
index 43e6e32..d9fa3d2 100644
--- a/fs/ocfs2/dlm/dlmrecovery.c
+++ b/fs/ocfs2/dlm/dlmrecovery.c
@@ -30,7 +30,6 @@
 #include <linux/types.h>
 #include <linux/slab.h>
 #include <linux/highmem.h>
-#include <linux/utsname.h>
 #include <linux/init.h>
 #include <linux/sysctl.h>
 #include <linux/random.h>
diff --git a/fs/ocfs2/dlm/dlmthread.c b/fs/ocfs2/dlm/dlmthread.c
index 98569e8..52ec020 100644
--- a/fs/ocfs2/dlm/dlmthread.c
+++ b/fs/ocfs2/dlm/dlmthread.c
@@ -30,7 +30,6 @@
 #include <linux/types.h>
 #include <linux/slab.h>
 #include <linux/highmem.h>
-#include <linux/utsname.h>
 #include <linux/init.h>
 #include <linux/sysctl.h>
 #include <linux/random.h>
diff --git a/fs/ocfs2/dlm/dlmunlock.c b/fs/ocfs2/dlm/dlmunlock.c
index 756f5b0..00f53b2 100644
--- a/fs/ocfs2/dlm/dlmunlock.c
+++ b/fs/ocfs2/dlm/dlmunlock.c
@@ -30,7 +30,6 @@
 #include <linux/types.h>
 #include <linux/slab.h>
 #include <linux/highmem.h>
-#include <linux/utsname.h>
 #include <linux/init.h>
 #include <linux/sysctl.h>
 #include <linux/random.h>
diff --git a/fs/ocfs2/mmap.c b/fs/ocfs2/mmap.c
index b606496..3973761 100644
--- a/fs/ocfs2/mmap.c
+++ b/fs/ocfs2/mmap.c
@@ -202,7 +202,7 @@ out:
 	return ret;
 }
 
-static struct vm_operations_struct ocfs2_file_vm_ops = {
+static const struct vm_operations_struct ocfs2_file_vm_ops = {
 	.fault		= ocfs2_fault,
 	.page_mkwrite	= ocfs2_page_mkwrite,
 };
diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index 24feb44..c0e48ae 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -28,7 +28,6 @@
 #include <linux/types.h>
 #include <linux/slab.h>
 #include <linux/highmem.h>
-#include <linux/utsname.h>
 #include <linux/init.h>
 #include <linux/random.h>
 #include <linux/statfs.h>
@@ -374,7 +373,7 @@ static ssize_t ocfs2_debug_read(struct file *file, char __user *buf,
 }
 #endif	/* CONFIG_DEBUG_FS */
 
-static struct file_operations ocfs2_osb_debug_fops = {
+static const struct file_operations ocfs2_osb_debug_fops = {
 	.open =		ocfs2_osb_debug_open,
 	.release =	ocfs2_debug_release,
 	.read =		ocfs2_debug_read,
diff --git a/fs/ocfs2/symlink.c b/fs/ocfs2/symlink.c
index 579dd1b..e342103 100644
--- a/fs/ocfs2/symlink.c
+++ b/fs/ocfs2/symlink.c
@@ -38,7 +38,6 @@
 #include <linux/types.h>
 #include <linux/slab.h>
 #include <linux/pagemap.h>
-#include <linux/utsname.h>
 #include <linux/namei.h>
 
 #define MLOG_MASK_PREFIX ML_NAMEI
diff --git a/fs/omfs/dir.c b/fs/omfs/dir.c
index 3680bae..b42d624 100644
--- a/fs/omfs/dir.c
+++ b/fs/omfs/dir.c
@@ -498,7 +498,7 @@ const struct inode_operations omfs_dir_inops = {
 	.rmdir = omfs_rmdir,
 };
 
-struct file_operations omfs_dir_operations = {
+const struct file_operations omfs_dir_operations = {
 	.read = generic_read_dir,
 	.readdir = omfs_readdir,
 	.llseek = generic_file_llseek,
diff --git a/fs/omfs/file.c b/fs/omfs/file.c
index 4845fbb..399487c 100644
--- a/fs/omfs/file.c
+++ b/fs/omfs/file.c
@@ -322,7 +322,7 @@ static sector_t omfs_bmap(struct address_space *mapping, sector_t block)
 	return generic_block_bmap(mapping, block, omfs_get_block);
 }
 
-struct file_operations omfs_file_operations = {
+const struct file_operations omfs_file_operations = {
 	.llseek = generic_file_llseek,
 	.read = do_sync_read,
 	.write = do_sync_write,
diff --git a/fs/omfs/omfs.h b/fs/omfs/omfs.h
index df71039..ebe2fdb 100644
--- a/fs/omfs/omfs.h
+++ b/fs/omfs/omfs.h
@@ -44,14 +44,14 @@ extern int omfs_allocate_range(struct super_block *sb, int min_request,
 extern int omfs_clear_range(struct super_block *sb, u64 block, int count);
 
 /* dir.c */
-extern struct file_operations omfs_dir_operations;
+extern const struct file_operations omfs_dir_operations;
 extern const struct inode_operations omfs_dir_inops;
 extern int omfs_make_empty(struct inode *inode, struct super_block *sb);
 extern int omfs_is_bad(struct omfs_sb_info *sbi, struct omfs_header *header,
 			u64 fsblock);
 
 /* file.c */
-extern struct file_operations omfs_file_operations;
+extern const struct file_operations omfs_file_operations;
 extern const struct inode_operations omfs_file_inops;
 extern const struct address_space_operations omfs_aops;
 extern void omfs_make_empty_table(struct buffer_head *bh, int offset);
diff --git a/fs/proc/array.c b/fs/proc/array.c
index 0c6bc60..07f77a7 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -322,6 +322,8 @@ static inline void task_context_switch_counts(struct seq_file *m,
 			p->nivcsw);
 }
 
+#ifdef CONFIG_MMU
+
 struct stack_stats {
 	struct vm_area_struct *vma;
 	unsigned long	startpage;
@@ -402,6 +404,11 @@ static inline void task_show_stack_usage(struct seq_file *m,
 		mmput(mm);
 	}
 }
+#else
+static void task_show_stack_usage(struct seq_file *m, struct task_struct *task)
+{
+}
+#endif		/* CONFIG_MMU */
 
 int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
 			struct pid *pid, struct task_struct *task)
diff --git a/fs/proc/kcore.c b/fs/proc/kcore.c
index 5601337..a44a789 100644
--- a/fs/proc/kcore.c
+++ b/fs/proc/kcore.c
@@ -23,7 +23,6 @@
 #include <asm/io.h>
 #include <linux/list.h>
 #include <linux/ioport.h>
-#include <linux/mm.h>
 #include <linux/memory.h>
 #include <asm/sections.h>
 
diff --git a/fs/proc/meminfo.c b/fs/proc/meminfo.c
index 171e052..c7bff4f 100644
--- a/fs/proc/meminfo.c
+++ b/fs/proc/meminfo.c
@@ -97,7 +97,11 @@ static int meminfo_proc_show(struct seq_file *m, void *v)
 		"Committed_AS:   %8lu kB\n"
 		"VmallocTotal:   %8lu kB\n"
 		"VmallocUsed:    %8lu kB\n"
-		"VmallocChunk:   %8lu kB\n",
+		"VmallocChunk:   %8lu kB\n"
+#ifdef CONFIG_MEMORY_FAILURE
+		"HardwareCorrupted: %8lu kB\n"
+#endif
+		,
 		K(i.totalram),
 		K(i.freeram),
 		K(i.bufferram),
@@ -144,6 +148,9 @@ static int meminfo_proc_show(struct seq_file *m, void *v)
 		(unsigned long)VMALLOC_TOTAL >> 10,
 		vmi.used >> 10,
 		vmi.largest_chunk >> 10
+#ifdef CONFIG_MEMORY_FAILURE
+		,atomic_long_read(&mce_bad_pages) << (PAGE_SHIFT - 10)
+#endif
 		);
 
 	hugetlb_report_meminfo(m);
diff --git a/fs/proc/page.c b/fs/proc/page.c
index 2281c2c..5033ce0 100644
--- a/fs/proc/page.c
+++ b/fs/proc/page.c
@@ -94,6 +94,7 @@ static const struct file_operations proc_kpagecount_operations = {
 #define KPF_COMPOUND_TAIL	16
 #define KPF_HUGE		17
 #define KPF_UNEVICTABLE		18
+#define KPF_HWPOISON		19
 #define KPF_NOPAGE		20
 
 #define KPF_KSM			21
@@ -180,6 +181,10 @@ static u64 get_uflags(struct page *page)
 	u |= kpf_copy_bit(k, KPF_UNEVICTABLE,	PG_unevictable);
 	u |= kpf_copy_bit(k, KPF_MLOCKED,	PG_mlocked);
 
+#ifdef CONFIG_MEMORY_FAILURE
+	u |= kpf_copy_bit(k, KPF_HWPOISON,	PG_hwpoison);
+#endif
+
 #ifdef CONFIG_IA64_UNCACHED_ALLOCATOR
 	u |= kpf_copy_bit(k, KPF_UNCACHED,	PG_uncached);
 #endif
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index 9b1e4e9..f667e8a 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -153,7 +153,7 @@ static ssize_t proc_sys_call_handler(struct file *filp, void __user *buf,
 
 	/* careful: calling conventions are nasty here */
 	res = count;
-	error = table->proc_handler(table, write, filp, buf, &res, ppos);
+	error = table->proc_handler(table, write, buf, &res, ppos);
 	if (!error)
 		error = res;
 out:
diff --git a/fs/proc/uptime.c b/fs/proc/uptime.c
index 0c10a0b..766b1d4 100644
--- a/fs/proc/uptime.c
+++ b/fs/proc/uptime.c
@@ -4,13 +4,18 @@
 #include <linux/sched.h>
 #include <linux/seq_file.h>
 #include <linux/time.h>
+#include <linux/kernel_stat.h>
 #include <asm/cputime.h>
 
 static int uptime_proc_show(struct seq_file *m, void *v)
 {
 	struct timespec uptime;
 	struct timespec idle;
-	cputime_t idletime = cputime_add(init_task.utime, init_task.stime);
+	int i;
+	cputime_t idletime = cputime_zero;
+
+	for_each_possible_cpu(i)
+		idletime = cputime64_add(idletime, kstat_cpu(i).cpustat.idle);
 
 	do_posix_clock_monotonic_gettime(&uptime);
 	monotonic_to_bootbased(&uptime);
diff --git a/fs/ramfs/file-nommu.c b/fs/ramfs/file-nommu.c
index 11f0c06..32fae40 100644
--- a/fs/ramfs/file-nommu.c
+++ b/fs/ramfs/file-nommu.c
@@ -69,14 +69,11 @@ int ramfs_nommu_expand_for_mapping(struct inode *inode, size_t newsize)
 	/* make various checks */
 	order = get_order(newsize);
 	if (unlikely(order >= MAX_ORDER))
-		goto too_big;
+		return -EFBIG;
 
-	limit = current->signal->rlim[RLIMIT_FSIZE].rlim_cur;
-	if (limit != RLIM_INFINITY && newsize > limit)
-		goto fsize_exceeded;
-
-	if (newsize > inode->i_sb->s_maxbytes)
-		goto too_big;
+	ret = inode_newsize_ok(inode, newsize);
+	if (ret)
+		return ret;
 
 	i_size_write(inode, newsize);
 
@@ -118,12 +115,7 @@ int ramfs_nommu_expand_for_mapping(struct inode *inode, size_t newsize)
 
 	return 0;
 
- fsize_exceeded:
-	send_sig(SIGXFSZ, current, 0);
- too_big:
-	return -EFBIG;
-
- add_error:
+add_error:
 	while (loop < npages)
 		__free_page(pages + loop++);
 	return ret;
diff --git a/fs/read_write.c b/fs/read_write.c
index 6c8c55d..3ac2898 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -839,9 +839,6 @@ static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos,
 		max = min(in_inode->i_sb->s_maxbytes, out_inode->i_sb->s_maxbytes);
 
 	pos = *ppos;
-	retval = -EINVAL;
-	if (unlikely(pos < 0))
-		goto fput_out;
 	if (unlikely(pos + count > max)) {
 		retval = -EOVERFLOW;
 		if (pos >= max)
diff --git a/fs/romfs/storage.c b/fs/romfs/storage.c
index b3208ad..71e2b4d 100644
--- a/fs/romfs/storage.c
+++ b/fs/romfs/storage.c
@@ -253,11 +253,11 @@ ssize_t romfs_dev_strnlen(struct super_block *sb,
 
 #ifdef CONFIG_ROMFS_ON_MTD
 	if (sb->s_mtd)
-		return romfs_mtd_strnlen(sb, pos, limit);
+		return romfs_mtd_strnlen(sb, pos, maxlen);
 #endif
 #ifdef CONFIG_ROMFS_ON_BLOCK
 	if (sb->s_bdev)
-		return romfs_blk_strnlen(sb, pos, limit);
+		return romfs_blk_strnlen(sb, pos, maxlen);
 #endif
 	return -EIO;
 }
diff --git a/fs/romfs/super.c b/fs/romfs/super.c
index 47f132d..c117fa8 100644
--- a/fs/romfs/super.c
+++ b/fs/romfs/super.c
@@ -528,7 +528,7 @@ static int romfs_fill_super(struct super_block *sb, void *data, int silent)
 	pos = (ROMFH_SIZE + len + 1 + ROMFH_PAD) & ROMFH_MASK;
 
 	root = romfs_iget(sb, pos);
-	if (!root)
+	if (IS_ERR(root))
 		goto error;
 
 	sb->s_root = d_alloc_root(root);
diff --git a/fs/select.c b/fs/select.c
index a201fc3..fd38ce2 100644
--- a/fs/select.c
+++ b/fs/select.c
@@ -15,6 +15,7 @@
  */
 
 #include <linux/kernel.h>
+#include <linux/sched.h>
 #include <linux/syscalls.h>
 #include <linux/module.h>
 #include <linux/slab.h>
diff --git a/fs/seq_file.c b/fs/seq_file.c
index 6c95927..eae7d9d 100644
--- a/fs/seq_file.c
+++ b/fs/seq_file.c
@@ -429,20 +429,21 @@ EXPORT_SYMBOL(mangle_path);
  */
 int seq_path(struct seq_file *m, struct path *path, char *esc)
 {
-	if (m->count < m->size) {
-		char *s = m->buf + m->count;
-		char *p = d_path(path, s, m->size - m->count);
+	char *buf;
+	size_t size = seq_get_buf(m, &buf);
+	int res = -1;
+
+	if (size) {
+		char *p = d_path(path, buf, size);
 		if (!IS_ERR(p)) {
-			s = mangle_path(s, p, esc);
-			if (s) {
-				p = m->buf + m->count;
-				m->count = s - m->buf;
-				return s - p;
-			}
+			char *end = mangle_path(buf, p, esc);
+			if (end)
+				res = end - buf;
 		}
 	}
-	m->count = m->size;
-	return -1;
+	seq_commit(m, res);
+
+	return res;
 }
 EXPORT_SYMBOL(seq_path);
 
@@ -454,26 +455,28 @@ EXPORT_SYMBOL(seq_path);
 int seq_path_root(struct seq_file *m, struct path *path, struct path *root,
 		  char *esc)
 {
-	int err = -ENAMETOOLONG;
-	if (m->count < m->size) {
-		char *s = m->buf + m->count;
+	char *buf;
+	size_t size = seq_get_buf(m, &buf);
+	int res = -ENAMETOOLONG;
+
+	if (size) {
 		char *p;
 
 		spin_lock(&dcache_lock);
-		p = __d_path(path, root, s, m->size - m->count);
+		p = __d_path(path, root, buf, size);
 		spin_unlock(&dcache_lock);
-		err = PTR_ERR(p);
+		res = PTR_ERR(p);
 		if (!IS_ERR(p)) {
-			s = mangle_path(s, p, esc);
-			if (s) {
-				p = m->buf + m->count;
-				m->count = s - m->buf;
-				return 0;
-			}
+			char *end = mangle_path(buf, p, esc);
+			if (end)
+				res = end - buf;
+			else
+				res = -ENAMETOOLONG;
 		}
 	}
-	m->count = m->size;
-	return err;
+	seq_commit(m, res);
+
+	return res < 0 ? res : 0;
 }
 
 /*
@@ -481,20 +484,21 @@ int seq_path_root(struct seq_file *m, struct path *path, struct path *root,
  */
 int seq_dentry(struct seq_file *m, struct dentry *dentry, char *esc)
 {
-	if (m->count < m->size) {
-		char *s = m->buf + m->count;
-		char *p = dentry_path(dentry, s, m->size - m->count);
+	char *buf;
+	size_t size = seq_get_buf(m, &buf);
+	int res = -1;
+
+	if (size) {
+		char *p = dentry_path(dentry, buf, size);
 		if (!IS_ERR(p)) {
-			s = mangle_path(s, p, esc);
-			if (s) {
-				p = m->buf + m->count;
-				m->count = s - m->buf;
-				return s - p;
-			}
+			char *end = mangle_path(buf, p, esc);
+			if (end)
+				res = end - buf;
 		}
 	}
-	m->count = m->size;
-	return -1;
+	seq_commit(m, res);
+
+	return res;
 }
 
 int seq_bitmap(struct seq_file *m, const unsigned long *bits,
diff --git a/fs/smbfs/inode.c b/fs/smbfs/inode.c
index 1402d2d..1c4c8f0 100644
--- a/fs/smbfs/inode.c
+++ b/fs/smbfs/inode.c
@@ -459,14 +459,8 @@ smb_show_options(struct seq_file *s, struct vfsmount *m)
 static void
 smb_unload_nls(struct smb_sb_info *server)
 {
-	if (server->remote_nls) {
-		unload_nls(server->remote_nls);
-		server->remote_nls = NULL;
-	}
-	if (server->local_nls) {
-		unload_nls(server->local_nls);
-		server->local_nls = NULL;
-	}
+	unload_nls(server->remote_nls);
+	unload_nls(server->local_nls);
 }
 
 static void
diff --git a/fs/super.c b/fs/super.c
index 0e7207b..19eb70b 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -465,6 +465,48 @@ rescan:
 }
 
 EXPORT_SYMBOL(get_super);
+
+/**
+ * get_active_super - get an active reference to the superblock of a device
+ * @bdev: device to get the superblock for
+ *
+ * Scans the superblock list and finds the superblock of the file system
+ * mounted on the device given.  Returns the superblock with an active
+ * reference and s_umount held exclusively or %NULL if none was found.
+ */
+struct super_block *get_active_super(struct block_device *bdev)
+{
+	struct super_block *sb;
+
+	if (!bdev)
+		return NULL;
+
+	spin_lock(&sb_lock);
+	list_for_each_entry(sb, &super_blocks, s_list) {
+		if (sb->s_bdev != bdev)
+			continue;
+
+		sb->s_count++;
+		spin_unlock(&sb_lock);
+		down_write(&sb->s_umount);
+		if (sb->s_root) {
+			spin_lock(&sb_lock);
+			if (sb->s_count > S_BIAS) {
+				atomic_inc(&sb->s_active);
+				sb->s_count--;
+				spin_unlock(&sb_lock);
+				return sb;
+			}
+			spin_unlock(&sb_lock);
+		}
+		up_write(&sb->s_umount);
+		put_super(sb);
+		yield();
+		spin_lock(&sb_lock);
+	}
+	spin_unlock(&sb_lock);
+	return NULL;
+}
  
 struct super_block * user_get_super(dev_t dev)
 {
@@ -527,11 +569,15 @@ int do_remount_sb(struct super_block *sb, int flags, void *data, int force)
 {
 	int retval;
 	int remount_rw;
-	
+
+	if (sb->s_frozen != SB_UNFROZEN)
+		return -EBUSY;
+
 #ifdef CONFIG_BLOCK
 	if (!(flags & MS_RDONLY) && bdev_read_only(sb->s_bdev))
 		return -EACCES;
 #endif
+
 	if (flags & MS_RDONLY)
 		acct_auto_close(sb);
 	shrink_dcache_sb(sb);
@@ -743,9 +789,14 @@ int get_sb_bdev(struct file_system_type *fs_type,
 	 * will protect the lockfs code from trying to start a snapshot
 	 * while we are mounting
 	 */
-	down(&bdev->bd_mount_sem);
+	mutex_lock(&bdev->bd_fsfreeze_mutex);
+	if (bdev->bd_fsfreeze_count > 0) {
+		mutex_unlock(&bdev->bd_fsfreeze_mutex);
+		error = -EBUSY;
+		goto error_bdev;
+	}
 	s = sget(fs_type, test_bdev_super, set_bdev_super, bdev);
-	up(&bdev->bd_mount_sem);
+	mutex_unlock(&bdev->bd_fsfreeze_mutex);
 	if (IS_ERR(s))
 		goto error_s;
 
@@ -892,6 +943,16 @@ vfs_kern_mount(struct file_system_type *type, int flags, const char *name, void
  	if (error)
  		goto out_sb;
 
+	/*
+	 * filesystems should never set s_maxbytes larger than MAX_LFS_FILESIZE
+	 * but s_maxbytes was an unsigned long long for many releases. Throw
+	 * this warning for a little while to try and catch filesystems that
+	 * violate this rule. This warning should be either removed or
+	 * converted to a BUG() in 2.6.34.
+	 */
+	WARN((mnt->mnt_sb->s_maxbytes < 0), "%s set sb->s_maxbytes to "
+		"negative value (%lld)\n", type->name, mnt->mnt_sb->s_maxbytes);
+
 	mnt->mnt_mountpoint = mnt->mnt_root;
 	mnt->mnt_parent = mnt;
 	up_write(&mnt->mnt_sb->s_umount);
diff --git a/fs/sysfs/bin.c b/fs/sysfs/bin.c
index 2524714..60c702b 100644
--- a/fs/sysfs/bin.c
+++ b/fs/sysfs/bin.c
@@ -40,7 +40,7 @@ struct bin_buffer {
 	struct mutex			mutex;
 	void				*buffer;
 	int				mmapped;
-	struct vm_operations_struct 	*vm_ops;
+	const struct vm_operations_struct *vm_ops;
 	struct file			*file;
 	struct hlist_node		list;
 };
@@ -331,7 +331,7 @@ static int bin_migrate(struct vm_area_struct *vma, const nodemask_t *from,
 }
 #endif
 
-static struct vm_operations_struct bin_vm_ops = {
+static const struct vm_operations_struct bin_vm_ops = {
 	.open		= bin_vma_open,
 	.close		= bin_vma_close,
 	.fault		= bin_fault,
diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index 0050fc4..5fad489 100644
--- a/fs/sysfs/dir.c
+++ b/fs/sysfs/dir.c
@@ -894,7 +894,8 @@ int sysfs_move_dir(struct kobject *kobj, struct kobject *new_parent_kobj)
 
 	mutex_lock(&sysfs_rename_mutex);
 	BUG_ON(!sd->s_parent);
-	new_parent_sd = new_parent_kobj->sd ? new_parent_kobj->sd : &sysfs_root;
+	new_parent_sd = (new_parent_kobj && new_parent_kobj->sd) ?
+		new_parent_kobj->sd : &sysfs_root;
 
 	error = 0;
 	if (sd->s_parent == new_parent_sd)
diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index 561a9c0..f5ea468 100644
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -268,7 +268,7 @@ static int sysfs_get_open_dirent(struct sysfs_dirent *sd,
 	struct sysfs_open_dirent *od, *new_od = NULL;
 
  retry:
-	spin_lock(&sysfs_open_dirent_lock);
+	spin_lock_irq(&sysfs_open_dirent_lock);
 
 	if (!sd->s_attr.open && new_od) {
 		sd->s_attr.open = new_od;
@@ -281,7 +281,7 @@ static int sysfs_get_open_dirent(struct sysfs_dirent *sd,
 		list_add_tail(&buffer->list, &od->buffers);
 	}
 
-	spin_unlock(&sysfs_open_dirent_lock);
+	spin_unlock_irq(&sysfs_open_dirent_lock);
 
 	if (od) {
 		kfree(new_od);
@@ -315,8 +315,9 @@ static void sysfs_put_open_dirent(struct sysfs_dirent *sd,
 				  struct sysfs_buffer *buffer)
 {
 	struct sysfs_open_dirent *od = sd->s_attr.open;
+	unsigned long flags;
 
-	spin_lock(&sysfs_open_dirent_lock);
+	spin_lock_irqsave(&sysfs_open_dirent_lock, flags);
 
 	list_del(&buffer->list);
 	if (atomic_dec_and_test(&od->refcnt))
@@ -324,7 +325,7 @@ static void sysfs_put_open_dirent(struct sysfs_dirent *sd,
 	else
 		od = NULL;
 
-	spin_unlock(&sysfs_open_dirent_lock);
+	spin_unlock_irqrestore(&sysfs_open_dirent_lock, flags);
 
 	kfree(od);
 }
@@ -456,8 +457,9 @@ static unsigned int sysfs_poll(struct file *filp, poll_table *wait)
 void sysfs_notify_dirent(struct sysfs_dirent *sd)
 {
 	struct sysfs_open_dirent *od;
+	unsigned long flags;
 
-	spin_lock(&sysfs_open_dirent_lock);
+	spin_lock_irqsave(&sysfs_open_dirent_lock, flags);
 
 	od = sd->s_attr.open;
 	if (od) {
@@ -465,7 +467,7 @@ void sysfs_notify_dirent(struct sysfs_dirent *sd)
 		wake_up_interruptible(&od->poll);
 	}
 
-	spin_unlock(&sysfs_open_dirent_lock);
+	spin_unlock_irqrestore(&sysfs_open_dirent_lock, flags);
 }
 EXPORT_SYMBOL_GPL(sysfs_notify_dirent);
 
diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c
index 2e6481a..1009adc 100644
--- a/fs/ubifs/file.c
+++ b/fs/ubifs/file.c
@@ -1534,7 +1534,7 @@ out_unlock:
 	return err;
 }
 
-static struct vm_operations_struct ubifs_file_vm_ops = {
+static const struct vm_operations_struct ubifs_file_vm_ops = {
 	.fault        = filemap_fault,
 	.page_mkwrite = ubifs_vm_page_mkwrite,
 };
diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c
index d5e5559..c2e30ee 100644
--- a/fs/xfs/linux-2.6/xfs_aops.c
+++ b/fs/xfs/linux-2.6/xfs_aops.c
@@ -186,19 +186,37 @@ xfs_destroy_ioend(
 }
 
 /*
+ * If the end of the current ioend is beyond the current EOF,
+ * return the new EOF value, otherwise zero.
+ */
+STATIC xfs_fsize_t
+xfs_ioend_new_eof(
+	xfs_ioend_t		*ioend)
+{
+	xfs_inode_t		*ip = XFS_I(ioend->io_inode);
+	xfs_fsize_t		isize;
+	xfs_fsize_t		bsize;
+
+	bsize = ioend->io_offset + ioend->io_size;
+	isize = MAX(ip->i_size, ip->i_new_size);
+	isize = MIN(isize, bsize);
+	return isize > ip->i_d.di_size ? isize : 0;
+}
+
+/*
  * Update on-disk file size now that data has been written to disk.
  * The current in-memory file size is i_size.  If a write is beyond
  * eof i_new_size will be the intended file size until i_size is
  * updated.  If this write does not extend all the way to the valid
  * file size then restrict this update to the end of the write.
  */
+
 STATIC void
 xfs_setfilesize(
 	xfs_ioend_t		*ioend)
 {
 	xfs_inode_t		*ip = XFS_I(ioend->io_inode);
 	xfs_fsize_t		isize;
-	xfs_fsize_t		bsize;
 
 	ASSERT((ip->i_d.di_mode & S_IFMT) == S_IFREG);
 	ASSERT(ioend->io_type != IOMAP_READ);
@@ -206,16 +224,10 @@ xfs_setfilesize(
 	if (unlikely(ioend->io_error))
 		return;
 
-	bsize = ioend->io_offset + ioend->io_size;
-
 	xfs_ilock(ip, XFS_ILOCK_EXCL);
-
-	isize = MAX(ip->i_size, ip->i_new_size);
-	isize = MIN(isize, bsize);
-
-	if (ip->i_d.di_size < isize) {
+	isize = xfs_ioend_new_eof(ioend);
+	if (isize) {
 		ip->i_d.di_size = isize;
-		ip->i_update_core = 1;
 		xfs_mark_inode_dirty_sync(ip);
 	}
 
@@ -404,10 +416,16 @@ xfs_submit_ioend_bio(
 	struct bio	*bio)
 {
 	atomic_inc(&ioend->io_remaining);
-
 	bio->bi_private = ioend;
 	bio->bi_end_io = xfs_end_bio;
 
+	/*
+	 * If the I/O is beyond EOF we mark the inode dirty immediately
+	 * but don't update the inode size until I/O completion.
+	 */
+	if (xfs_ioend_new_eof(ioend))
+		xfs_mark_inode_dirty_sync(XFS_I(ioend->io_inode));
+
 	submit_bio(WRITE, bio);
 	ASSERT(!bio_flagged(bio, BIO_EOPNOTSUPP));
 	bio_put(bio);
@@ -1635,4 +1653,5 @@ const struct address_space_operations xfs_address_space_operations = {
 	.direct_IO		= xfs_vm_direct_IO,
 	.migratepage		= buffer_migrate_page,
 	.is_partially_uptodate  = block_is_partially_uptodate,
+	.error_remove_page	= generic_error_remove_page,
 };
diff --git a/fs/xfs/linux-2.6/xfs_file.c b/fs/xfs/linux-2.6/xfs_file.c
index 988d8f8..eff61e2 100644
--- a/fs/xfs/linux-2.6/xfs_file.c
+++ b/fs/xfs/linux-2.6/xfs_file.c
@@ -42,7 +42,7 @@
 
 #include <linux/dcache.h>
 
-static struct vm_operations_struct xfs_file_vm_ops;
+static const struct vm_operations_struct xfs_file_vm_ops;
 
 STATIC ssize_t
 xfs_file_aio_read(
@@ -176,14 +176,7 @@ xfs_file_fsync(
 	struct dentry		*dentry,
 	int			datasync)
 {
-	struct inode		*inode = dentry->d_inode;
-	struct xfs_inode	*ip = XFS_I(inode);
-	int			error;
-
-	/* capture size updates in I/O completion before writing the inode. */
-	error = filemap_fdatawait(inode->i_mapping);
-	if (error)
-		return error;
+	struct xfs_inode	*ip = XFS_I(dentry->d_inode);
 
 	xfs_iflags_clear(ip, XFS_ITRUNCATED);
 	return -xfs_fsync(ip);
@@ -280,7 +273,7 @@ const struct file_operations xfs_dir_file_operations = {
 	.fsync		= xfs_file_fsync,
 };
 
-static struct vm_operations_struct xfs_file_vm_ops = {
+static const struct vm_operations_struct xfs_file_vm_ops = {
 	.fault		= filemap_fault,
 	.page_mkwrite	= xfs_vm_page_mkwrite,
 };
diff --git a/fs/xfs/linux-2.6/xfs_iops.c b/fs/xfs/linux-2.6/xfs_iops.c
index da0159d..cd42ef7 100644
--- a/fs/xfs/linux-2.6/xfs_iops.c
+++ b/fs/xfs/linux-2.6/xfs_iops.c
@@ -57,19 +57,22 @@
 #include <linux/fiemap.h>
 
 /*
- * Bring the atime in the XFS inode uptodate.
- * Used before logging the inode to disk or when the Linux inode goes away.
+ * Bring the timestamps in the XFS inode uptodate.
+ *
+ * Used before writing the inode to disk.
  */
 void
-xfs_synchronize_atime(
+xfs_synchronize_times(
 	xfs_inode_t	*ip)
 {
 	struct inode	*inode = VFS_I(ip);
 
-	if (!(inode->i_state & I_CLEAR)) {
-		ip->i_d.di_atime.t_sec = (__int32_t)inode->i_atime.tv_sec;
-		ip->i_d.di_atime.t_nsec = (__int32_t)inode->i_atime.tv_nsec;
-	}
+	ip->i_d.di_atime.t_sec = (__int32_t)inode->i_atime.tv_sec;
+	ip->i_d.di_atime.t_nsec = (__int32_t)inode->i_atime.tv_nsec;
+	ip->i_d.di_ctime.t_sec = (__int32_t)inode->i_ctime.tv_sec;
+	ip->i_d.di_ctime.t_nsec = (__int32_t)inode->i_ctime.tv_nsec;
+	ip->i_d.di_mtime.t_sec = (__int32_t)inode->i_mtime.tv_sec;
+	ip->i_d.di_mtime.t_nsec = (__int32_t)inode->i_mtime.tv_nsec;
 }
 
 /*
@@ -106,32 +109,20 @@ xfs_ichgtime(
 	if ((flags & XFS_ICHGTIME_MOD) &&
 	    !timespec_equal(&inode->i_mtime, &tv)) {
 		inode->i_mtime = tv;
-		ip->i_d.di_mtime.t_sec = (__int32_t)tv.tv_sec;
-		ip->i_d.di_mtime.t_nsec = (__int32_t)tv.tv_nsec;
 		sync_it = 1;
 	}
 	if ((flags & XFS_ICHGTIME_CHG) &&
 	    !timespec_equal(&inode->i_ctime, &tv)) {
 		inode->i_ctime = tv;
-		ip->i_d.di_ctime.t_sec = (__int32_t)tv.tv_sec;
-		ip->i_d.di_ctime.t_nsec = (__int32_t)tv.tv_nsec;
 		sync_it = 1;
 	}
 
 	/*
-	 * We update the i_update_core field _after_ changing
-	 * the timestamps in order to coordinate properly with
-	 * xfs_iflush() so that we don't lose timestamp updates.
-	 * This keeps us from having to hold the inode lock
-	 * while doing this.  We use the SYNCHRONIZE macro to
-	 * ensure that the compiler does not reorder the update
-	 * of i_update_core above the timestamp updates above.
+	 * Update complete - now make sure everyone knows that the inode
+	 * is dirty.
 	 */
-	if (sync_it) {
-		SYNCHRONIZE();
-		ip->i_update_core = 1;
+	if (sync_it)
 		xfs_mark_inode_dirty_sync(ip);
-	}
 }
 
 /*
@@ -506,10 +497,8 @@ xfs_vn_getattr(
 	stat->gid = ip->i_d.di_gid;
 	stat->ino = ip->i_ino;
 	stat->atime = inode->i_atime;
-	stat->mtime.tv_sec = ip->i_d.di_mtime.t_sec;
-	stat->mtime.tv_nsec = ip->i_d.di_mtime.t_nsec;
-	stat->ctime.tv_sec = ip->i_d.di_ctime.t_sec;
-	stat->ctime.tv_nsec = ip->i_d.di_ctime.t_nsec;
+	stat->mtime = inode->i_mtime;
+	stat->ctime = inode->i_ctime;
 	stat->blocks =
 		XFS_FSB_TO_BB(mp, ip->i_d.di_nblocks + ip->i_delayed_blks);
 
diff --git a/fs/xfs/linux-2.6/xfs_lrw.c b/fs/xfs/linux-2.6/xfs_lrw.c
index 49e4a6a..072050f 100644
--- a/fs/xfs/linux-2.6/xfs_lrw.c
+++ b/fs/xfs/linux-2.6/xfs_lrw.c
@@ -667,7 +667,7 @@ start:
 		xip->i_new_size = new_size;
 
 	if (likely(!(ioflags & IO_INVIS)))
-		xfs_ichgtime(xip, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
+		file_update_time(file);
 
 	/*
 	 * If the offset is beyond the size of the file, we have a couple
diff --git a/fs/xfs/linux-2.6/xfs_super.c b/fs/xfs/linux-2.6/xfs_super.c
index bdd41c8..18a4b8e 100644
--- a/fs/xfs/linux-2.6/xfs_super.c
+++ b/fs/xfs/linux-2.6/xfs_super.c
@@ -977,6 +977,28 @@ xfs_fs_inode_init_once(
 }
 
 /*
+ * Dirty the XFS inode when mark_inode_dirty_sync() is called so that
+ * we catch unlogged VFS level updates to the inode. Care must be taken
+ * here - the transaction code calls mark_inode_dirty_sync() to mark the
+ * VFS inode dirty in a transaction and clears the i_update_core field;
+ * it must clear the field after calling mark_inode_dirty_sync() to
+ * correctly indicate that the dirty state has been propagated into the
+ * inode log item.
+ *
+ * We need the barrier() to maintain correct ordering between unlogged
+ * updates and the transaction commit code that clears the i_update_core
+ * field. This requires all updates to be completed before marking the
+ * inode dirty.
+ */
+STATIC void
+xfs_fs_dirty_inode(
+	struct inode	*inode)
+{
+	barrier();
+	XFS_I(inode)->i_update_core = 1;
+}
+
+/*
  * Attempt to flush the inode, this will actually fail
  * if the inode is pinned, but we dirty the inode again
  * at the point when it is unpinned after a log write,
@@ -1126,7 +1148,7 @@ xfs_fs_put_super(
 }
 
 STATIC int
-xfs_fs_sync_super(
+xfs_fs_sync_fs(
 	struct super_block	*sb,
 	int			wait)
 {
@@ -1134,23 +1156,23 @@ xfs_fs_sync_super(
 	int			error;
 
 	/*
-	 * Treat a sync operation like a freeze.  This is to work
-	 * around a race in sync_inodes() which works in two phases
-	 * - an asynchronous flush, which can write out an inode
-	 * without waiting for file size updates to complete, and a
-	 * synchronous flush, which wont do anything because the
-	 * async flush removed the inode's dirty flag.  Also
-	 * sync_inodes() will not see any files that just have
-	 * outstanding transactions to be flushed because we don't
-	 * dirty the Linux inode until after the transaction I/O
-	 * completes.
+	 * Not much we can do for the first async pass.  Writing out the
+	 * superblock would be counter-productive as we are going to redirty
+	 * when writing out other data and metadata (and writing out a single
+	 * block is quite fast anyway).
+	 *
+	 * Try to asynchronously kick off quota syncing at least.
 	 */
-	if (wait || unlikely(sb->s_frozen == SB_FREEZE_WRITE))
-		error = xfs_quiesce_data(mp);
-	else
-		error = xfs_sync_fsdata(mp, 0);
+	if (!wait) {
+		xfs_qm_sync(mp, SYNC_TRYLOCK);
+		return 0;
+	}
+
+	error = xfs_quiesce_data(mp);
+	if (error)
+		return -error;
 
-	if (unlikely(laptop_mode)) {
+	if (laptop_mode) {
 		int	prev_sync_seq = mp->m_sync_seq;
 
 		/*
@@ -1169,7 +1191,7 @@ xfs_fs_sync_super(
 				mp->m_sync_seq != prev_sync_seq);
 	}
 
-	return -error;
+	return 0;
 }
 
 STATIC int
@@ -1539,10 +1561,11 @@ xfs_fs_get_sb(
 static const struct super_operations xfs_super_operations = {
 	.alloc_inode		= xfs_fs_alloc_inode,
 	.destroy_inode		= xfs_fs_destroy_inode,
+	.dirty_inode		= xfs_fs_dirty_inode,
 	.write_inode		= xfs_fs_write_inode,
 	.clear_inode		= xfs_fs_clear_inode,
 	.put_super		= xfs_fs_put_super,
-	.sync_fs		= xfs_fs_sync_super,
+	.sync_fs		= xfs_fs_sync_fs,
 	.freeze_fs		= xfs_fs_freeze,
 	.statfs			= xfs_fs_statfs,
 	.remount_fs		= xfs_fs_remount,
diff --git a/fs/xfs/linux-2.6/xfs_sync.c b/fs/xfs/linux-2.6/xfs_sync.c
index 320be6a..961df0a 100644
--- a/fs/xfs/linux-2.6/xfs_sync.c
+++ b/fs/xfs/linux-2.6/xfs_sync.c
@@ -309,11 +309,15 @@ xfs_sync_attr(
 STATIC int
 xfs_commit_dummy_trans(
 	struct xfs_mount	*mp,
-	uint			log_flags)
+	uint			flags)
 {
 	struct xfs_inode	*ip = mp->m_rootip;
 	struct xfs_trans	*tp;
 	int			error;
+	int			log_flags = XFS_LOG_FORCE;
+
+	if (flags & SYNC_WAIT)
+		log_flags |= XFS_LOG_SYNC;
 
 	/*
 	 * Put a dummy transaction in the log to tell recovery
@@ -331,13 +335,12 @@ xfs_commit_dummy_trans(
 	xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
 	xfs_trans_ihold(tp, ip);
 	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
-	/* XXX(hch): ignoring the error here.. */
 	error = xfs_trans_commit(tp, 0);
-
 	xfs_iunlock(ip, XFS_ILOCK_EXCL);
 
+	/* the log force ensures this transaction is pushed to disk */
 	xfs_log_force(mp, 0, log_flags);
-	return 0;
+	return error;
 }
 
 int
@@ -385,7 +388,20 @@ xfs_sync_fsdata(
 	else
 		XFS_BUF_ASYNC(bp);
 
-	return xfs_bwrite(mp, bp);
+	error = xfs_bwrite(mp, bp);
+	if (error)
+		return error;
+
+	/*
+	 * If this is a data integrity sync make sure all pending buffers
+	 * are flushed out for the log coverage check below.
+	 */
+	if (flags & SYNC_WAIT)
+		xfs_flush_buftarg(mp->m_ddev_targp, 1);
+
+	if (xfs_log_need_covered(mp))
+		error = xfs_commit_dummy_trans(mp, flags);
+	return error;
 
  out_brelse:
 	xfs_buf_relse(bp);
@@ -419,14 +435,16 @@ xfs_quiesce_data(
 	/* push non-blocking */
 	xfs_sync_data(mp, 0);
 	xfs_qm_sync(mp, SYNC_TRYLOCK);
-	xfs_filestream_flush(mp);
 
-	/* push and block */
+	/* push and block till complete */
 	xfs_sync_data(mp, SYNC_WAIT);
 	xfs_qm_sync(mp, SYNC_WAIT);
 
+	/* drop inode references pinned by filestreams */
+	xfs_filestream_flush(mp);
+
 	/* write superblock and hoover up shutdown errors */
-	error = xfs_sync_fsdata(mp, 0);
+	error = xfs_sync_fsdata(mp, SYNC_WAIT);
 
 	/* flush data-only devices */
 	if (mp->m_rtdev_targp)
@@ -570,8 +588,6 @@ xfs_sync_worker(
 		/* dgc: errors ignored here */
 		error = xfs_qm_sync(mp, SYNC_TRYLOCK);
 		error = xfs_sync_fsdata(mp, SYNC_TRYLOCK);
-		if (xfs_log_need_covered(mp))
-			error = xfs_commit_dummy_trans(mp, XFS_LOG_FORCE);
 	}
 	mp->m_sync_seq++;
 	wake_up(&mp->m_wait_single_sync_task);
diff --git a/fs/xfs/linux-2.6/xfs_sysctl.c b/fs/xfs/linux-2.6/xfs_sysctl.c
index 916c0ff..c5bc67c 100644
--- a/fs/xfs/linux-2.6/xfs_sysctl.c
+++ b/fs/xfs/linux-2.6/xfs_sysctl.c
@@ -26,7 +26,6 @@ STATIC int
 xfs_stats_clear_proc_handler(
 	ctl_table	*ctl,
 	int		write,
-	struct file	*filp,
 	void		__user *buffer,
 	size_t		*lenp,
 	loff_t		*ppos)
@@ -34,7 +33,7 @@ xfs_stats_clear_proc_handler(
 	int		c, ret, *valp = ctl->data;
 	__uint32_t	vn_active;
 
-	ret = proc_dointvec_minmax(ctl, write, filp, buffer, lenp, ppos);
+	ret = proc_dointvec_minmax(ctl, write, buffer, lenp, ppos);
 
 	if (!ret && write && *valp) {
 		printk("XFS Clearing xfsstats\n");
diff --git a/fs/xfs/xfs_dfrag.c b/fs/xfs/xfs_dfrag.c
index 7465f9e..ab89a7e 100644
--- a/fs/xfs/xfs_dfrag.c
+++ b/fs/xfs/xfs_dfrag.c
@@ -206,10 +206,10 @@ xfs_swap_extents(
 	 * process that the file was not changed out from
 	 * under it.
 	 */
-	if ((sbp->bs_ctime.tv_sec != ip->i_d.di_ctime.t_sec) ||
-	    (sbp->bs_ctime.tv_nsec != ip->i_d.di_ctime.t_nsec) ||
-	    (sbp->bs_mtime.tv_sec != ip->i_d.di_mtime.t_sec) ||
-	    (sbp->bs_mtime.tv_nsec != ip->i_d.di_mtime.t_nsec)) {
+	if ((sbp->bs_ctime.tv_sec != VFS_I(ip)->i_ctime.tv_sec) ||
+	    (sbp->bs_ctime.tv_nsec != VFS_I(ip)->i_ctime.tv_nsec) ||
+	    (sbp->bs_mtime.tv_sec != VFS_I(ip)->i_mtime.tv_sec) ||
+	    (sbp->bs_mtime.tv_nsec != VFS_I(ip)->i_mtime.tv_nsec)) {
 		error = XFS_ERROR(EBUSY);
 		goto out_unlock;
 	}
diff --git a/fs/xfs/xfs_dir2_leaf.c b/fs/xfs/xfs_dir2_leaf.c
index fa913e45..41ad537 100644
--- a/fs/xfs/xfs_dir2_leaf.c
+++ b/fs/xfs/xfs_dir2_leaf.c
@@ -854,6 +854,7 @@ xfs_dir2_leaf_getdents(
 			 */
 			ra_want = howmany(bufsize + mp->m_dirblksize,
 					  mp->m_sb.sb_blocksize) - 1;
+			ASSERT(ra_want >= 0);
 
 			/*
 			 * If we don't have as many as we want, and we haven't
@@ -1088,7 +1089,8 @@ xfs_dir2_leaf_getdents(
 		 */
 		ptr += length;
 		curoff += length;
-		bufsize -= length;
+		/* bufsize may have just been a guess; don't go negative */
+		bufsize = bufsize > length ? bufsize - length : 0;
 	}
 
 	/*
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index c1dc7ef..b92a4fa 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -3068,9 +3068,9 @@ xfs_iflush_int(
 	SYNCHRONIZE();
 
 	/*
-	 * Make sure to get the latest atime from the Linux inode.
+	 * Make sure to get the latest timestamps from the Linux inode.
 	 */
-	xfs_synchronize_atime(ip);
+	xfs_synchronize_times(ip);
 
 	if (XFS_TEST_ERROR(be16_to_cpu(dip->di_magic) != XFS_DINODE_MAGIC,
 			       mp, XFS_ERRTAG_IFLUSH_1, XFS_RANDOM_IFLUSH_1)) {
diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index 0b38b9a..41555de 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -504,7 +504,7 @@ void		xfs_ichgtime(xfs_inode_t *, int);
 void		xfs_lock_inodes(xfs_inode_t **, int, uint);
 void		xfs_lock_two_inodes(xfs_inode_t *, xfs_inode_t *, uint);
 
-void		xfs_synchronize_atime(xfs_inode_t *);
+void		xfs_synchronize_times(xfs_inode_t *);
 void		xfs_mark_inode_dirty_sync(xfs_inode_t *);
 
 #if defined(XFS_INODE_TRACE)
diff --git a/fs/xfs/xfs_inode_item.c b/fs/xfs/xfs_inode_item.c
index 47d5b66..9794b87 100644
--- a/fs/xfs/xfs_inode_item.c
+++ b/fs/xfs/xfs_inode_item.c
@@ -232,6 +232,15 @@ xfs_inode_item_format(
 	nvecs	     = 1;
 
 	/*
+	 * Make sure the linux inode is dirty. We do this before
+	 * clearing i_update_core as the VFS will call back into
+	 * XFS here and set i_update_core, so we need to dirty the
+	 * inode first so that the ordering of i_update_core and
+	 * unlogged modifications still works as described below.
+	 */
+	xfs_mark_inode_dirty_sync(ip);
+
+	/*
 	 * Clear i_update_core if the timestamps (or any other
 	 * non-transactional modification) need flushing/logging
 	 * and we're about to log them with the rest of the core.
@@ -263,14 +272,9 @@ xfs_inode_item_format(
 	}
 
 	/*
-	 * Make sure to get the latest atime from the Linux inode.
+	 * Make sure to get the latest timestamps from the Linux inode.
 	 */
-	xfs_synchronize_atime(ip);
-
-	/*
-	 * make sure the linux inode is dirty
-	 */
-	xfs_mark_inode_dirty_sync(ip);
+	xfs_synchronize_times(ip);
 
 	vecp->i_addr = (xfs_caddr_t)&ip->i_d;
 	vecp->i_len  = sizeof(struct xfs_icdinode);
diff --git a/fs/xfs/xfs_itable.c b/fs/xfs/xfs_itable.c
index b68f910..62efab2 100644
--- a/fs/xfs/xfs_itable.c
+++ b/fs/xfs/xfs_itable.c
@@ -59,6 +59,7 @@ xfs_bulkstat_one_iget(
 {
 	xfs_icdinode_t	*dic;	/* dinode core info pointer */
 	xfs_inode_t	*ip;		/* incore inode pointer */
+	struct inode	*inode;
 	int		error;
 
 	error = xfs_iget(mp, NULL, ino,
@@ -72,6 +73,7 @@ xfs_bulkstat_one_iget(
 	ASSERT(ip->i_imap.im_blkno != 0);
 
 	dic = &ip->i_d;
+	inode = VFS_I(ip);
 
 	/* xfs_iget returns the following without needing
 	 * further change.
@@ -83,16 +85,19 @@ xfs_bulkstat_one_iget(
 	buf->bs_uid = dic->di_uid;
 	buf->bs_gid = dic->di_gid;
 	buf->bs_size = dic->di_size;
+
 	/*
-	 * We are reading the atime from the Linux inode because the
-	 * dinode might not be uptodate.
+	 * We need to read the timestamps from the Linux inode because
+	 * the VFS keeps writing directly into the inode structure instead
+	 * of telling us about the updates.
 	 */
-	buf->bs_atime.tv_sec = VFS_I(ip)->i_atime.tv_sec;
-	buf->bs_atime.tv_nsec = VFS_I(ip)->i_atime.tv_nsec;
-	buf->bs_mtime.tv_sec = dic->di_mtime.t_sec;
-	buf->bs_mtime.tv_nsec = dic->di_mtime.t_nsec;
-	buf->bs_ctime.tv_sec = dic->di_ctime.t_sec;
-	buf->bs_ctime.tv_nsec = dic->di_ctime.t_nsec;
+	buf->bs_atime.tv_sec = inode->i_atime.tv_sec;
+	buf->bs_atime.tv_nsec = inode->i_atime.tv_nsec;
+	buf->bs_mtime.tv_sec = inode->i_mtime.tv_sec;
+	buf->bs_mtime.tv_nsec = inode->i_mtime.tv_nsec;
+	buf->bs_ctime.tv_sec = inode->i_ctime.tv_sec;
+	buf->bs_ctime.tv_nsec = inode->i_ctime.tv_nsec;
+
 	buf->bs_xflags = xfs_ip2xflags(ip);
 	buf->bs_extsize = dic->di_extsize << mp->m_sb.sb_blocklog;
 	buf->bs_extents = dic->di_nextents;
diff --git a/fs/xfs/xfs_vnodeops.c b/fs/xfs/xfs_vnodeops.c
index a434f28..b572f7e 100644
--- a/fs/xfs/xfs_vnodeops.c
+++ b/fs/xfs/xfs_vnodeops.c
@@ -2476,12 +2476,6 @@ xfs_reclaim(
 	ASSERT(XFS_FORCED_SHUTDOWN(ip->i_mount) || ip->i_delayed_blks == 0);
 
 	/*
-	 * Make sure the atime in the XFS inode is correct before freeing the
-	 * Linux inode.
-	 */
-	xfs_synchronize_atime(ip);
-
-	/*
 	 * If we have nothing to flush with this inode then complete the
 	 * teardown now, otherwise break the link between the xfs inode and the
 	 * linux inode and clean up the xfs inode later. This avoids flushing