Initial import of modified Linux 2.6.28 tree

Original upstream URL:
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git | branch linux-2.6.28.y

12 files changed, 2843 insertions, 0 deletions

diff --git a/fs/9p/Makefile b/fs/9p/Makefile
new file mode 100644
index 0000000..bc7f0d1
--- /dev/null
+++ b/fs/9p/Makefile
@@ -0,0 +1,12 @@
+obj-$(CONFIG_9P_FS) := 9p.o
+
+9p-objs := \
+	vfs_super.o \
+	vfs_inode.o \
+	vfs_addr.o \
+	vfs_file.o \
+	vfs_dir.o \
+	vfs_dentry.o \
+	v9fs.o \
+	fid.o \
+
diff --git a/fs/9p/fid.c b/fs/9p/fid.c
new file mode 100644
index 0000000..2a983d4
--- /dev/null
+++ b/fs/9p/fid.c
@@ -0,0 +1,209 @@
+/*
+ * V9FS FID Management
+ *
+ *  Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
+ *  Copyright (C) 2005, 2006 by Eric Van Hensbergen <ericvh@gmail.com>
+ *
+ *  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/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/sched.h>
+#include <linux/idr.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+
+#include "v9fs.h"
+#include "v9fs_vfs.h"
+#include "fid.h"
+
+/**
+ * v9fs_fid_add - add a fid to a dentry
+ * @dentry: dentry that the fid is being added to
+ * @fid: fid to add
+ *
+ */
+
+int v9fs_fid_add(struct dentry *dentry, struct p9_fid *fid)
+{
+	struct v9fs_dentry *dent;
+
+	P9_DPRINTK(P9_DEBUG_VFS, "fid %d dentry %s\n",
+					fid->fid, dentry->d_name.name);
+
+	dent = dentry->d_fsdata;
+	if (!dent) {
+		dent = kmalloc(sizeof(struct v9fs_dentry), GFP_KERNEL);
+		if (!dent)
+			return -ENOMEM;
+
+		spin_lock_init(&dent->lock);
+		INIT_LIST_HEAD(&dent->fidlist);
+		dentry->d_fsdata = dent;
+	}
+
+	spin_lock(&dent->lock);
+	list_add(&fid->dlist, &dent->fidlist);
+	spin_unlock(&dent->lock);
+
+	return 0;
+}
+
+/**
+ * v9fs_fid_find - retrieve a fid that belongs to the specified uid
+ * @dentry: dentry to look for fid in
+ * @uid: return fid that belongs to the specified user
+ * @any: if non-zero, return any fid associated with the dentry
+ *
+ */
+
+static struct p9_fid *v9fs_fid_find(struct dentry *dentry, u32 uid, int any)
+{
+	struct v9fs_dentry *dent;
+	struct p9_fid *fid, *ret;
+
+	P9_DPRINTK(P9_DEBUG_VFS, " dentry: %s (%p) uid %d any %d\n",
+		dentry->d_name.name, dentry, uid, any);
+	dent = (struct v9fs_dentry *) dentry->d_fsdata;
+	ret = NULL;
+	if (dent) {
+		spin_lock(&dent->lock);
+		list_for_each_entry(fid, &dent->fidlist, dlist) {
+			if (any || fid->uid == uid) {
+				ret = fid;
+				break;
+			}
+		}
+		spin_unlock(&dent->lock);
+	}
+
+	return ret;
+}
+
+/**
+ * v9fs_fid_lookup - lookup for a fid, try to walk if not found
+ * @dentry: dentry to look for fid in
+ *
+ * Look for a fid in the specified dentry for the current user.
+ * If no fid is found, try to create one walking from a fid from the parent
+ * dentry (if it has one), or the root dentry. If the user haven't accessed
+ * the fs yet, attach now and walk from the root.
+ */
+
+struct p9_fid *v9fs_fid_lookup(struct dentry *dentry)
+{
+	int i, n, l, clone, any, access;
+	u32 uid;
+	struct p9_fid *fid;
+	struct dentry *d, *ds;
+	struct v9fs_session_info *v9ses;
+	char **wnames, *uname;
+
+	v9ses = v9fs_inode2v9ses(dentry->d_inode);
+	access = v9ses->flags & V9FS_ACCESS_MASK;
+	switch (access) {
+	case V9FS_ACCESS_SINGLE:
+	case V9FS_ACCESS_USER:
+		uid = current->fsuid;
+		any = 0;
+		break;
+
+	case V9FS_ACCESS_ANY:
+		uid = v9ses->uid;
+		any = 1;
+		break;
+
+	default:
+		uid = ~0;
+		any = 0;
+		break;
+	}
+
+	fid = v9fs_fid_find(dentry, uid, any);
+	if (fid)
+		return fid;
+
+	ds = dentry->d_parent;
+	fid = v9fs_fid_find(ds, uid, any);
+	if (!fid) { /* walk from the root */
+		n = 0;
+		for (ds = dentry; !IS_ROOT(ds); ds = ds->d_parent)
+			n++;
+
+		fid = v9fs_fid_find(ds, uid, any);
+		if (!fid) { /* the user is not attached to the fs yet */
+			if (access == V9FS_ACCESS_SINGLE)
+				return ERR_PTR(-EPERM);
+
+			if (v9fs_extended(v9ses))
+				uname = NULL;
+			else
+				uname = v9ses->uname;
+
+			fid = p9_client_attach(v9ses->clnt, NULL, uname, uid,
+				v9ses->aname);
+
+			if (IS_ERR(fid))
+				return fid;
+
+			v9fs_fid_add(ds, fid);
+		}
+	} else /* walk from the parent */
+		n = 1;
+
+	if (ds == dentry)
+		return fid;
+
+	wnames = kmalloc(sizeof(char *) * n, GFP_KERNEL);
+	if (!wnames)
+		return ERR_PTR(-ENOMEM);
+
+	for (d = dentry, i = (n-1); i >= 0; i--, d = d->d_parent)
+		wnames[i] = (char *) d->d_name.name;
+
+	clone = 1;
+	i = 0;
+	while (i < n) {
+		l = min(n - i, P9_MAXWELEM);
+		fid = p9_client_walk(fid, l, &wnames[i], clone);
+		if (IS_ERR(fid)) {
+			kfree(wnames);
+			return fid;
+		}
+
+		i += l;
+		clone = 0;
+	}
+
+	kfree(wnames);
+	v9fs_fid_add(dentry, fid);
+	return fid;
+}
+
+struct p9_fid *v9fs_fid_clone(struct dentry *dentry)
+{
+	struct p9_fid *fid, *ret;
+
+	fid = v9fs_fid_lookup(dentry);
+	if (IS_ERR(fid))
+		return fid;
+
+	ret = p9_client_walk(fid, 0, NULL, 1);
+	return ret;
+}
diff --git a/fs/9p/fid.h b/fs/9p/fid.h
new file mode 100644
index 0000000..c3bbd6a
--- /dev/null
+++ b/fs/9p/fid.h
@@ -0,0 +1,47 @@
+/*
+ * V9FS FID Management
+ *
+ *  Copyright (C) 2005 by Eric Van Hensbergen <ericvh@gmail.com>
+ *
+ *  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/list.h>
+
+/**
+ * struct v9fs_dentry - 9p private data stored in dentry d_fsdata
+ * @lock: protects the fidlist
+ * @fidlist: list of FIDs currently associated with this dentry
+ *
+ * This structure defines the 9p private data associated with
+ * a particular dentry.  In particular, this private data is used
+ * to lookup which 9P FID handle should be used for a particular VFS
+ * operation.  FID handles are associated with dentries instead of
+ * inodes in order to more closely map functionality to the Plan 9
+ * expected behavior for FID reclaimation and tracking.
+ *
+ * See Also: Mapping FIDs to Linux VFS model in
+ * Design and Implementation of the Linux 9P File System documentation
+ */
+struct v9fs_dentry {
+	spinlock_t lock; /* protect fidlist */
+	struct list_head fidlist;
+};
+
+struct p9_fid *v9fs_fid_lookup(struct dentry *dentry);
+struct p9_fid *v9fs_fid_clone(struct dentry *dentry);
+int v9fs_fid_add(struct dentry *dentry, struct p9_fid *fid);
diff --git a/fs/9p/v9fs.c b/fs/9p/v9fs.c
new file mode 100644
index 0000000..332b5ff
--- /dev/null
+++ b/fs/9p/v9fs.c
@@ -0,0 +1,328 @@
+/*
+ *  linux/fs/9p/v9fs.c
+ *
+ *  This file contains functions assisting in mapping VFS to 9P2000
+ *
+ *  Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  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/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/sched.h>
+#include <linux/parser.h>
+#include <linux/idr.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+#include <net/9p/transport.h>
+#include "v9fs.h"
+#include "v9fs_vfs.h"
+
+/*
+  * 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,
+	/* Options that take no arguments */
+	Opt_nodevmap,
+	/* Cache options */
+	Opt_cache_loose,
+	/* Access options */
+	Opt_access,
+	/* Error token */
+	Opt_err
+};
+
+static const match_table_t tokens = {
+	{Opt_debug, "debug=%x"},
+	{Opt_dfltuid, "dfltuid=%u"},
+	{Opt_dfltgid, "dfltgid=%u"},
+	{Opt_afid, "afid=%u"},
+	{Opt_uname, "uname=%s"},
+	{Opt_remotename, "aname=%s"},
+	{Opt_nodevmap, "nodevmap"},
+	{Opt_cache_loose, "cache=loose"},
+	{Opt_cache_loose, "loose"},
+	{Opt_access, "access=%s"},
+	{Opt_err, NULL}
+};
+
+/**
+ * v9fs_parse_options - parse mount options into session structure
+ * @v9ses: existing v9fs session information
+ *
+ * Return 0 upon success, -ERRNO upon failure.
+ */
+
+static int v9fs_parse_options(struct v9fs_session_info *v9ses)
+{
+	char *options;
+	substring_t args[MAX_OPT_ARGS];
+	char *p;
+	int option = 0;
+	char *s, *e;
+	int ret = 0;
+
+	/* setup defaults */
+	v9ses->afid = ~0;
+	v9ses->debug = 0;
+	v9ses->cache = 0;
+
+	if (!v9ses->options)
+		return 0;
+
+	options = kstrdup(v9ses->options, GFP_KERNEL);
+	if (!options) {
+		P9_DPRINTK(P9_DEBUG_ERROR,
+			   "failed to allocate copy of option string\n");
+		return -ENOMEM;
+	}
+
+	while ((p = strsep(&options, ",")) != NULL) {
+		int token;
+		if (!*p)
+			continue;
+		token = match_token(p, tokens, args);
+		if (token < Opt_uname) {
+			int r = match_int(&args[0], &option);
+			if (r < 0) {
+				P9_DPRINTK(P9_DEBUG_ERROR,
+					"integer field, but no integer?\n");
+				ret = r;
+				continue;
+			}
+		}
+		switch (token) {
+		case Opt_debug:
+			v9ses->debug = option;
+#ifdef CONFIG_NET_9P_DEBUG
+			p9_debug_level = option;
+#endif
+			break;
+
+		case Opt_dfltuid:
+			v9ses->dfltuid = option;
+			break;
+		case Opt_dfltgid:
+			v9ses->dfltgid = option;
+			break;
+		case Opt_afid:
+			v9ses->afid = option;
+			break;
+		case Opt_uname:
+			match_strlcpy(v9ses->uname, &args[0], PATH_MAX);
+			break;
+		case Opt_remotename:
+			match_strlcpy(v9ses->aname, &args[0], PATH_MAX);
+			break;
+		case Opt_nodevmap:
+			v9ses->nodev = 1;
+			break;
+		case Opt_cache_loose:
+			v9ses->cache = CACHE_LOOSE;
+			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;
+			}
+			v9ses->flags &= ~V9FS_ACCESS_MASK;
+			if (strcmp(s, "user") == 0)
+				v9ses->flags |= V9FS_ACCESS_USER;
+			else if (strcmp(s, "any") == 0)
+				v9ses->flags |= V9FS_ACCESS_ANY;
+			else {
+				v9ses->flags |= V9FS_ACCESS_SINGLE;
+				v9ses->uid = simple_strtoul(s, &e, 10);
+				if (*e != '\0')
+					v9ses->uid = ~0;
+			}
+			kfree(s);
+			break;
+
+		default:
+			continue;
+		}
+	}
+	kfree(options);
+	return ret;
+}
+
+/**
+ * v9fs_session_init - initialize session
+ * @v9ses: session information structure
+ * @dev_name: device being mounted
+ * @data: options
+ *
+ */
+
+struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
+		  const char *dev_name, char *data)
+{
+	int retval = -EINVAL;
+	struct p9_fid *fid;
+	int rc;
+
+	v9ses->uname = __getname();
+	if (!v9ses->uname)
+		return ERR_PTR(-ENOMEM);
+
+	v9ses->aname = __getname();
+	if (!v9ses->aname) {
+		__putname(v9ses->uname);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	v9ses->flags = V9FS_EXTENDED | V9FS_ACCESS_USER;
+	strcpy(v9ses->uname, V9FS_DEFUSER);
+	strcpy(v9ses->aname, V9FS_DEFANAME);
+	v9ses->uid = ~0;
+	v9ses->dfltuid = V9FS_DEFUID;
+	v9ses->dfltgid = V9FS_DEFGID;
+	if (data) {
+		v9ses->options = kstrdup(data, GFP_KERNEL);
+		if (!v9ses->options) {
+			P9_DPRINTK(P9_DEBUG_ERROR,
+			   "failed to allocate copy of option string\n");
+			retval = -ENOMEM;
+			goto error;
+		}
+	}
+
+	rc = v9fs_parse_options(v9ses);
+	if (rc < 0) {
+		retval = rc;
+		goto error;
+	}
+
+	v9ses->clnt = p9_client_create(dev_name, v9ses->options);
+
+	if (IS_ERR(v9ses->clnt)) {
+		retval = PTR_ERR(v9ses->clnt);
+		v9ses->clnt = NULL;
+		P9_DPRINTK(P9_DEBUG_ERROR, "problem initializing 9p client\n");
+		goto error;
+	}
+
+	if (!v9ses->clnt->dotu)
+		v9ses->flags &= ~V9FS_EXTENDED;
+
+	v9ses->maxdata = v9ses->clnt->msize - P9_IOHDRSZ;
+
+	/* for legacy mode, fall back to V9FS_ACCESS_ANY */
+	if (!v9fs_extended(v9ses) &&
+		((v9ses->flags&V9FS_ACCESS_MASK) == V9FS_ACCESS_USER)) {
+
+		v9ses->flags &= ~V9FS_ACCESS_MASK;
+		v9ses->flags |= V9FS_ACCESS_ANY;
+		v9ses->uid = ~0;
+	}
+
+	fid = p9_client_attach(v9ses->clnt, NULL, v9ses->uname, ~0,
+							v9ses->aname);
+	if (IS_ERR(fid)) {
+		retval = PTR_ERR(fid);
+		fid = NULL;
+		P9_DPRINTK(P9_DEBUG_ERROR, "cannot attach\n");
+		goto error;
+	}
+
+	if ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_SINGLE)
+		fid->uid = v9ses->uid;
+	else
+		fid->uid = ~0;
+
+	return fid;
+
+error:
+	return ERR_PTR(retval);
+}
+
+/**
+ * v9fs_session_close - shutdown a session
+ * @v9ses: session information structure
+ *
+ */
+
+void v9fs_session_close(struct v9fs_session_info *v9ses)
+{
+	if (v9ses->clnt) {
+		p9_client_destroy(v9ses->clnt);
+		v9ses->clnt = NULL;
+	}
+
+	__putname(v9ses->uname);
+	__putname(v9ses->aname);
+	kfree(v9ses->options);
+}
+
+/**
+ * v9fs_session_cancel - terminate a session
+ * @v9ses: session to terminate
+ *
+ * mark transport as disconnected and cancel all pending requests.
+ */
+
+void v9fs_session_cancel(struct v9fs_session_info *v9ses) {
+	P9_DPRINTK(P9_DEBUG_ERROR, "cancel session %p\n", v9ses);
+	p9_client_disconnect(v9ses->clnt);
+}
+
+extern int v9fs_error_init(void);
+
+/**
+ * v9fs_init - Initialize module
+ *
+ */
+
+static int __init init_v9fs(void)
+{
+	printk(KERN_INFO "Installing v9fs 9p2000 file system support\n");
+	/* TODO: Setup list of registered trasnport modules */
+	return register_filesystem(&v9fs_fs_type);
+}
+
+/**
+ * v9fs_init - shutdown module
+ *
+ */
+
+static void __exit exit_v9fs(void)
+{
+	unregister_filesystem(&v9fs_fs_type);
+}
+
+module_init(init_v9fs)
+module_exit(exit_v9fs)
+
+MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>");
+MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
+MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
+MODULE_LICENSE("GPL");
diff --git a/fs/9p/v9fs.h b/fs/9p/v9fs.h
new file mode 100644
index 0000000..a7d5671
--- /dev/null
+++ b/fs/9p/v9fs.h
@@ -0,0 +1,123 @@
+/*
+ * V9FS definitions.
+ *
+ *  Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  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
+ *
+ */
+
+/**
+ * enum p9_session_flags - option flags for each 9P session
+ * @V9FS_EXTENDED: whether or not to use 9P2000.u extensions
+ * @V9FS_ACCESS_SINGLE: only the mounting user can access the hierarchy
+ * @V9FS_ACCESS_USER: a new attach will be issued for every user (default)
+ * @V9FS_ACCESS_ANY: use a single attach for all users
+ * @V9FS_ACCESS_MASK: bit mask of different ACCESS options
+ *
+ * Session flags reflect options selected by users at mount time
+ */
+enum p9_session_flags {
+	V9FS_EXTENDED		= 0x01,
+	V9FS_ACCESS_SINGLE	= 0x02,
+	V9FS_ACCESS_USER	= 0x04,
+	V9FS_ACCESS_ANY		= 0x06,
+	V9FS_ACCESS_MASK	= 0x06,
+};
+
+/* possible values of ->cache */
+/**
+ * enum p9_cache_modes - user specified cache preferences
+ * @CACHE_NONE: do not cache data, dentries, or directory contents (default)
+ * @CACHE_LOOSE: cache data, dentries, and directory contents w/no consistency
+ *
+ * eventually support loose, tight, time, session, default always none
+ */
+
+enum p9_cache_modes {
+	CACHE_NONE,
+	CACHE_LOOSE,
+};
+
+/**
+ * struct v9fs_session_info - per-instance session information
+ * @flags: session options of type &p9_session_flags
+ * @nodev: set to 1 to disable device mapping
+ * @debug: debug level
+ * @afid: authentication handle
+ * @cache: cache mode of type &p9_cache_modes
+ * @options: copy of options string given by user
+ * @uname: string user name to mount hierarchy as
+ * @aname: mount specifier for remote hierarchy
+ * @maxdata: maximum data to be sent/recvd per protocol message
+ * @dfltuid: default numeric userid to mount hierarchy as
+ * @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
+ *
+ * This structure holds state for each session instance established during
+ * a sys_mount() .
+ *
+ * Bugs: there seems to be a lot of state which could be condensed and/or
+ * removed.
+ */
+
+struct v9fs_session_info {
+	/* options */
+	unsigned char flags;
+	unsigned char nodev;
+	unsigned short debug;
+	unsigned int afid;
+	unsigned int cache;
+
+	char *options;		/* copy of mount options */
+	char *uname;		/* user name to mount as */
+	char *aname;		/* name of remote hierarchy being mounted */
+	unsigned int maxdata;	/* max data for client interface */
+	unsigned int dfltuid;	/* default uid/muid for legacy support */
+	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;
+};
+
+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);
+void v9fs_session_cancel(struct v9fs_session_info *v9ses);
+
+#define V9FS_MAGIC 0x01021997
+
+/* other default globals */
+#define V9FS_PORT	564
+#define V9FS_DEFUSER	"nobody"
+#define V9FS_DEFANAME	""
+#define V9FS_DEFUID	(-2)
+#define V9FS_DEFGID	(-2)
+
+static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode)
+{
+	return (inode->i_sb->s_fs_info);
+}
+
+static inline int v9fs_extended(struct v9fs_session_info *v9ses)
+{
+	return v9ses->flags & V9FS_EXTENDED;
+}
diff --git a/fs/9p/v9fs_vfs.h b/fs/9p/v9fs_vfs.h
new file mode 100644
index 0000000..c295ba7
--- /dev/null
+++ b/fs/9p/v9fs_vfs.h
@@ -0,0 +1,56 @@
+/*
+ * V9FS VFS extensions.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  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
+ *
+ */
+
+/* plan9 semantics are that created files are implicitly opened.
+ * But linux semantics are that you call create, then open.
+ * the plan9 approach is superior as it provides an atomic
+ * open.
+ * we track the create fid here. When the file is opened, if fidopen is
+ * non-zero, we use the fid and can skip some steps.
+ * there may be a better way to do this, but I don't know it.
+ * one BAD way is to clunk the fid on create, then open it again:
+ * you lose the atomicity of file open
+ */
+
+/* special case:
+ * unlink calls remove, which is an implicit clunk. So we have to track
+ * that kind of thing so that we don't try to clunk a dead fid.
+ */
+
+extern struct file_system_type v9fs_fs_type;
+extern const struct address_space_operations v9fs_addr_operations;
+extern const struct file_operations v9fs_file_operations;
+extern const struct file_operations v9fs_dir_operations;
+extern struct dentry_operations v9fs_dentry_operations;
+extern struct dentry_operations v9fs_cached_dentry_operations;
+
+struct inode *v9fs_get_inode(struct super_block *sb, int mode);
+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);
+int v9fs_file_open(struct inode *inode, struct file *file);
+void v9fs_inode2stat(struct inode *inode, struct p9_wstat *stat);
+void v9fs_dentry_release(struct dentry *);
+int v9fs_uflags2omode(int uflags, int extended);
+
+ssize_t v9fs_file_readn(struct file *, char *, char __user *, u32, u64);
diff --git a/fs/9p/vfs_addr.c b/fs/9p/vfs_addr.c
new file mode 100644
index 0000000..6fcb1e7
--- /dev/null
+++ b/fs/9p/vfs_addr.c
@@ -0,0 +1,77 @@
+/*
+ *  linux/fs/9p/vfs_addr.c
+ *
+ * This file contians vfs address (mmap) ops for 9P2000.
+ *
+ *  Copyright (C) 2005 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  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/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/inet.h>
+#include <linux/pagemap.h>
+#include <linux/idr.h>
+#include <linux/sched.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+
+#include "v9fs.h"
+#include "v9fs_vfs.h"
+
+/**
+ * v9fs_vfs_readpage - read an entire page in from 9P
+ *
+ * @filp: file being read
+ * @page: structure to page
+ *
+ */
+
+static int v9fs_vfs_readpage(struct file *filp, struct page *page)
+{
+	int retval;
+	loff_t offset;
+	char *buffer;
+
+	P9_DPRINTK(P9_DEBUG_VFS, "\n");
+	buffer = kmap(page);
+	offset = page_offset(page);
+
+	retval = v9fs_file_readn(filp, buffer, NULL, offset, PAGE_CACHE_SIZE);
+	if (retval < 0)
+		goto done;
+
+	memset(buffer + retval, 0, PAGE_CACHE_SIZE - retval);
+	flush_dcache_page(page);
+	SetPageUptodate(page);
+	retval = 0;
+
+done:
+	kunmap(page);
+	unlock_page(page);
+	return retval;
+}
+
+const struct address_space_operations v9fs_addr_operations = {
+      .readpage = v9fs_vfs_readpage,
+};
diff --git a/fs/9p/vfs_dentry.c b/fs/9p/vfs_dentry.c
new file mode 100644
index 0000000..06dcc7c
--- /dev/null
+++ b/fs/9p/vfs_dentry.c
@@ -0,0 +1,115 @@
+/*
+ *  linux/fs/9p/vfs_dentry.c
+ *
+ * This file contians vfs dentry ops for the 9P2000 protocol.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  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/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/pagemap.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/inet.h>
+#include <linux/namei.h>
+#include <linux/idr.h>
+#include <linux/sched.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+
+#include "v9fs.h"
+#include "v9fs_vfs.h"
+#include "fid.h"
+
+/**
+ * v9fs_dentry_delete - called when dentry refcount equals 0
+ * @dentry:  dentry in question
+ *
+ * By returning 1 here we should remove cacheing of unused
+ * dentry components.
+ *
+ */
+
+static int v9fs_dentry_delete(struct dentry *dentry)
+{
+	P9_DPRINTK(P9_DEBUG_VFS, " dentry: %s (%p)\n", dentry->d_name.name,
+									dentry);
+
+	return 1;
+}
+
+/**
+ * v9fs_cached_dentry_delete - called when dentry refcount equals 0
+ * @dentry:  dentry in question
+ *
+ * Only return 1 if our inode is invalid.  Only non-synthetic files
+ * (ones without mtime == 0) should be calling this function.
+ *
+ */
+
+static int v9fs_cached_dentry_delete(struct dentry *dentry)
+{
+	struct inode *inode = dentry->d_inode;
+	P9_DPRINTK(P9_DEBUG_VFS, " dentry: %s (%p)\n", dentry->d_name.name,
+									dentry);
+
+	if(!inode)
+		return 1;
+
+	return 0;
+}
+
+/**
+ * v9fs_dentry_release - called when dentry is going to be freed
+ * @dentry:  dentry that is being release
+ *
+ */
+
+void v9fs_dentry_release(struct dentry *dentry)
+{
+	struct v9fs_dentry *dent;
+	struct p9_fid *temp, *current_fid;
+
+	P9_DPRINTK(P9_DEBUG_VFS, " dentry: %s (%p)\n", dentry->d_name.name,
+									dentry);
+	dent = dentry->d_fsdata;
+	if (dent) {
+		list_for_each_entry_safe(current_fid, temp, &dent->fidlist,
+									dlist) {
+			p9_client_clunk(current_fid);
+		}
+
+		kfree(dent);
+		dentry->d_fsdata = NULL;
+	}
+}
+
+struct dentry_operations v9fs_cached_dentry_operations = {
+	.d_delete = v9fs_cached_dentry_delete,
+	.d_release = v9fs_dentry_release,
+};
+
+struct dentry_operations v9fs_dentry_operations = {
+	.d_delete = v9fs_dentry_delete,
+	.d_release = v9fs_dentry_release,
+};
diff --git a/fs/9p/vfs_dir.c b/fs/9p/vfs_dir.c
new file mode 100644
index 0000000..873cd31
--- /dev/null
+++ b/fs/9p/vfs_dir.c
@@ -0,0 +1,152 @@
+/*
+ * linux/fs/9p/vfs_dir.c
+ *
+ * This file contains vfs directory ops for the 9P2000 protocol.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  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/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/sched.h>
+#include <linux/inet.h>
+#include <linux/idr.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+
+#include "v9fs.h"
+#include "v9fs_vfs.h"
+#include "fid.h"
+
+/**
+ * dt_type - return file type
+ * @mistat: mistat structure
+ *
+ */
+
+static inline int dt_type(struct p9_wstat *mistat)
+{
+	unsigned long perm = mistat->mode;
+	int rettype = DT_REG;
+
+	if (perm & P9_DMDIR)
+		rettype = DT_DIR;
+	if (perm & P9_DMSYMLINK)
+		rettype = DT_LNK;
+
+	return rettype;
+}
+
+/**
+ * v9fs_dir_readdir - read a directory
+ * @filp: opened file structure
+ * @dirent: directory structure ???
+ * @filldir: function to populate directory structure ???
+ *
+ */
+
+static int v9fs_dir_readdir(struct file *filp, void *dirent, filldir_t filldir)
+{
+	int over;
+	struct p9_wstat st;
+	int err;
+	struct p9_fid *fid;
+	int buflen;
+	char *statbuf;
+	int n, i = 0;
+
+	P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", filp->f_path.dentry->d_name.name);
+	fid = filp->private_data;
+
+	buflen = fid->clnt->msize - P9_IOHDRSZ;
+	statbuf = kmalloc(buflen, GFP_KERNEL);
+	if (!statbuf)
+		return -ENOMEM;
+
+	while (1) {
+		err = v9fs_file_readn(filp, statbuf, NULL, buflen,
+								fid->rdir_fpos);
+		if (err <= 0)
+			break;
+
+		n = err;
+		while (i < n) {
+			err = p9stat_read(statbuf + i, buflen-i, &st,
+							fid->clnt->dotu);
+			if (err) {
+				P9_DPRINTK(P9_DEBUG_VFS, "returned %d\n", err);
+				err = -EIO;
+				p9stat_free(&st);
+				goto free_and_exit;
+			}
+
+			i += st.size+2;
+			fid->rdir_fpos += st.size+2;
+
+			over = filldir(dirent, st.name, strlen(st.name),
+			    filp->f_pos, v9fs_qid2ino(&st.qid), dt_type(&st));
+
+			filp->f_pos += st.size+2;
+
+			p9stat_free(&st);
+
+			if (over) {
+				err = 0;
+				goto free_and_exit;
+			}
+		}
+	}
+
+free_and_exit:
+	kfree(statbuf);
+	return err;
+}
+
+
+/**
+ * v9fs_dir_release - close a directory
+ * @inode: inode of the directory
+ * @filp: file pointer to a directory
+ *
+ */
+
+int v9fs_dir_release(struct inode *inode, struct file *filp)
+{
+	struct p9_fid *fid;
+
+	fid = filp->private_data;
+	P9_DPRINTK(P9_DEBUG_VFS,
+			"inode: %p filp: %p fid: %d\n", inode, filp, fid->fid);
+	filemap_write_and_wait(inode->i_mapping);
+	p9_client_clunk(fid);
+	return 0;
+}
+
+const struct file_operations v9fs_dir_operations = {
+	.read = generic_read_dir,
+	.llseek = generic_file_llseek,
+	.readdir = v9fs_dir_readdir,
+	.open = v9fs_file_open,
+	.release = v9fs_dir_release,
+};
diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c
new file mode 100644
index 0000000..68bf2af
--- /dev/null
+++ b/fs/9p/vfs_file.c
@@ -0,0 +1,272 @@
+/*
+ *  linux/fs/9p/vfs_file.c
+ *
+ * This file contians vfs file ops for 9P2000.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  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/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/sched.h>
+#include <linux/file.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/inet.h>
+#include <linux/list.h>
+#include <asm/uaccess.h>
+#include <linux/idr.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+
+#include "v9fs.h"
+#include "v9fs_vfs.h"
+#include "fid.h"
+
+static const struct file_operations v9fs_cached_file_operations;
+
+/**
+ * v9fs_file_open - open a file (or directory)
+ * @inode: inode to be opened
+ * @file: file being opened
+ *
+ */
+
+int v9fs_file_open(struct inode *inode, struct file *file)
+{
+	int err;
+	struct v9fs_session_info *v9ses;
+	struct p9_fid *fid;
+	int omode;
+
+	P9_DPRINTK(P9_DEBUG_VFS, "inode: %p file: %p \n", inode, file);
+	v9ses = v9fs_inode2v9ses(inode);
+	omode = v9fs_uflags2omode(file->f_flags, v9fs_extended(v9ses));
+	fid = file->private_data;
+	if (!fid) {
+		fid = v9fs_fid_clone(file->f_path.dentry);
+		if (IS_ERR(fid))
+			return PTR_ERR(fid);
+
+		err = p9_client_open(fid, omode);
+		if (err < 0) {
+			p9_client_clunk(fid);
+			return err;
+		}
+		if (omode & P9_OTRUNC) {
+			inode->i_size = 0;
+			inode->i_blocks = 0;
+		}
+		if ((file->f_flags & O_APPEND) && (!v9fs_extended(v9ses)))
+			generic_file_llseek(file, 0, SEEK_END);
+	}
+
+	file->private_data = fid;
+	if ((fid->qid.version) && (v9ses->cache)) {
+		P9_DPRINTK(P9_DEBUG_VFS, "cached");
+		/* enable cached file options */
+		if(file->f_op == &v9fs_file_operations)
+			file->f_op = &v9fs_cached_file_operations;
+	}
+
+	return 0;
+}
+
+/**
+ * v9fs_file_lock - lock a file (or directory)
+ * @filp: file to be locked
+ * @cmd: lock command
+ * @fl: file lock structure
+ *
+ * Bugs: this looks like a local only lock, we should extend into 9P
+ *       by using open exclusive
+ */
+
+static int v9fs_file_lock(struct file *filp, int cmd, struct file_lock *fl)
+{
+	int res = 0;
+	struct inode *inode = filp->f_path.dentry->d_inode;
+
+	P9_DPRINTK(P9_DEBUG_VFS, "filp: %p lock: %p\n", filp, fl);
+
+	/* No mandatory locks */
+	if (__mandatory_lock(inode))
+		return -ENOLCK;
+
+	if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
+		filemap_write_and_wait(inode->i_mapping);
+		invalidate_mapping_pages(&inode->i_data, 0, -1);
+	}
+
+	return res;
+}
+
+/**
+ * v9fs_file_readn - read from a file
+ * @filp: file pointer to read
+ * @data: data buffer to read data into
+ * @udata: user data buffer to read data into
+ * @count: size of buffer
+ * @offset: offset at which to read data
+ *
+ */
+
+ssize_t
+v9fs_file_readn(struct file *filp, char *data, char __user *udata, u32 count,
+	       u64 offset)
+{
+	int n, total;
+	struct p9_fid *fid = filp->private_data;
+
+	P9_DPRINTK(P9_DEBUG_VFS, "fid %d offset %llu count %d\n", fid->fid,
+					(long long unsigned) offset, count);
+
+	n = 0;
+	total = 0;
+	do {
+		n = p9_client_read(fid, data, udata, offset, count);
+		if (n <= 0)
+			break;
+
+		if (data)
+			data += n;
+		if (udata)
+			udata += n;
+
+		offset += n;
+		count -= n;
+		total += n;
+	} while (count > 0 && n == (fid->clnt->msize - P9_IOHDRSZ));
+
+	if (n < 0)
+		total = n;
+
+	return total;
+}
+
+/**
+ * v9fs_file_read - read from a file
+ * @filp: file pointer to read
+ * @udata: user data buffer to read data into
+ * @count: size of buffer
+ * @offset: offset at which to read data
+ *
+ */
+
+static ssize_t
+v9fs_file_read(struct file *filp, char __user *udata, size_t count,
+	       loff_t * offset)
+{
+	int ret;
+	struct p9_fid *fid;
+
+	P9_DPRINTK(P9_DEBUG_VFS, "count %zu offset %lld\n", count, *offset);
+	fid = filp->private_data;
+
+	if (count > (fid->clnt->msize - P9_IOHDRSZ))
+		ret = v9fs_file_readn(filp, NULL, udata, count, *offset);
+	else
+		ret = p9_client_read(fid, NULL, udata, *offset, count);
+
+	if (ret > 0)
+		*offset += ret;
+
+	return ret;
+}
+
+/**
+ * v9fs_file_write - write to a file
+ * @filp: file pointer to write
+ * @data: data buffer to write data from
+ * @count: size of buffer
+ * @offset: offset at which to write data
+ *
+ */
+
+static ssize_t
+v9fs_file_write(struct file *filp, const char __user * data,
+		size_t count, loff_t * offset)
+{
+	int n, rsize, total = 0;
+	struct p9_fid *fid;
+	struct p9_client *clnt;
+	struct inode *inode = filp->f_path.dentry->d_inode;
+	int origin = *offset;
+
+	P9_DPRINTK(P9_DEBUG_VFS, "data %p count %d offset %x\n", data,
+		(int)count, (int)*offset);
+
+	fid = filp->private_data;
+	clnt = fid->clnt;
+
+	rsize = fid->iounit;
+	if (!rsize || rsize > clnt->msize-P9_IOHDRSZ)
+		rsize = clnt->msize - P9_IOHDRSZ;
+
+	do {
+		if (count < rsize)
+			rsize = count;
+
+		n = p9_client_write(fid, NULL, data+total, *offset+total,
+									rsize);
+		if (n <= 0)
+			break;
+		count -= n;
+		total += n;
+	} while (count > 0);
+
+	if (total > 0) {
+		invalidate_inode_pages2_range(inode->i_mapping, origin,
+								origin+total);
+		*offset += total;
+	}
+
+	if (*offset > inode->i_size) {
+		inode->i_size = *offset;
+		inode->i_blocks = (inode->i_size + 512 - 1) >> 9;
+	}
+
+	if (n < 0)
+		return n;
+
+	return total;
+}
+
+static const struct file_operations v9fs_cached_file_operations = {
+	.llseek = generic_file_llseek,
+	.read = do_sync_read,
+	.aio_read = generic_file_aio_read,
+	.write = v9fs_file_write,
+	.open = v9fs_file_open,
+	.release = v9fs_dir_release,
+	.lock = v9fs_file_lock,
+	.mmap = generic_file_readonly_mmap,
+};
+
+const struct file_operations v9fs_file_operations = {
+	.llseek = generic_file_llseek,
+	.read = v9fs_file_read,
+	.write = v9fs_file_write,
+	.open = v9fs_file_open,
+	.release = v9fs_dir_release,
+	.lock = v9fs_file_lock,
+	.mmap = generic_file_readonly_mmap,
+};
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
new file mode 100644
index 0000000..2dfcf54
--- /dev/null
+++ b/fs/9p/vfs_inode.c
@@ -0,0 +1,1203 @@
+/*
+ *  linux/fs/9p/vfs_inode.c
+ *
+ * This file contains vfs inode ops for the 9P2000 protocol.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  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/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/pagemap.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/inet.h>
+#include <linux/namei.h>
+#include <linux/idr.h>
+#include <linux/sched.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+
+#include "v9fs.h"
+#include "v9fs_vfs.h"
+#include "fid.h"
+
+static const struct inode_operations v9fs_dir_inode_operations;
+static const struct inode_operations v9fs_dir_inode_operations_ext;
+static const struct inode_operations v9fs_file_inode_operations;
+static const struct inode_operations v9fs_symlink_inode_operations;
+
+/**
+ * unixmode2p9mode - convert unix mode bits to plan 9
+ * @v9ses: v9fs session information
+ * @mode: mode to convert
+ *
+ */
+
+static int unixmode2p9mode(struct v9fs_session_info *v9ses, int mode)
+{
+	int res;
+	res = mode & 0777;
+	if (S_ISDIR(mode))
+		res |= P9_DMDIR;
+	if (v9fs_extended(v9ses)) {
+		if (S_ISLNK(mode))
+			res |= P9_DMSYMLINK;
+		if (v9ses->nodev == 0) {
+			if (S_ISSOCK(mode))
+				res |= P9_DMSOCKET;
+			if (S_ISFIFO(mode))
+				res |= P9_DMNAMEDPIPE;
+			if (S_ISBLK(mode))
+				res |= P9_DMDEVICE;
+			if (S_ISCHR(mode))
+				res |= P9_DMDEVICE;
+		}
+
+		if ((mode & S_ISUID) == S_ISUID)
+			res |= P9_DMSETUID;
+		if ((mode & S_ISGID) == S_ISGID)
+			res |= P9_DMSETGID;
+		if ((mode & S_ISVTX) == S_ISVTX)
+			res |= P9_DMSETVTX;
+		if ((mode & P9_DMLINK))
+			res |= P9_DMLINK;
+	}
+
+	return res;
+}
+
+/**
+ * p9mode2unixmode- convert plan9 mode bits to unix mode bits
+ * @v9ses: v9fs session information
+ * @mode: mode to convert
+ *
+ */
+
+static int p9mode2unixmode(struct v9fs_session_info *v9ses, int mode)
+{
+	int res;
+
+	res = mode & 0777;
+
+	if ((mode & P9_DMDIR) == P9_DMDIR)
+		res |= S_IFDIR;
+	else if ((mode & P9_DMSYMLINK) && (v9fs_extended(v9ses)))
+		res |= S_IFLNK;
+	else if ((mode & P9_DMSOCKET) && (v9fs_extended(v9ses))
+		 && (v9ses->nodev == 0))
+		res |= S_IFSOCK;
+	else if ((mode & P9_DMNAMEDPIPE) && (v9fs_extended(v9ses))
+		 && (v9ses->nodev == 0))
+		res |= S_IFIFO;
+	else if ((mode & P9_DMDEVICE) && (v9fs_extended(v9ses))
+		 && (v9ses->nodev == 0))
+		res |= S_IFBLK;
+	else
+		res |= S_IFREG;
+
+	if (v9fs_extended(v9ses)) {
+		if ((mode & P9_DMSETUID) == P9_DMSETUID)
+			res |= S_ISUID;
+
+		if ((mode & P9_DMSETGID) == P9_DMSETGID)
+			res |= S_ISGID;
+
+		if ((mode & P9_DMSETVTX) == P9_DMSETVTX)
+			res |= S_ISVTX;
+	}
+
+	return res;
+}
+
+/**
+ * v9fs_uflags2omode- convert posix open flags to plan 9 mode bits
+ * @uflags: flags to convert
+ * @extended: if .u extensions are active
+ */
+
+int v9fs_uflags2omode(int uflags, int extended)
+{
+	int ret;
+
+	ret = 0;
+	switch (uflags&3) {
+	default:
+	case O_RDONLY:
+		ret = P9_OREAD;
+		break;
+
+	case O_WRONLY:
+		ret = P9_OWRITE;
+		break;
+
+	case O_RDWR:
+		ret = P9_ORDWR;
+		break;
+	}
+
+	if (uflags & O_TRUNC)
+		ret |= P9_OTRUNC;
+
+	if (extended) {
+		if (uflags & O_EXCL)
+			ret |= P9_OEXCL;
+
+		if (uflags & O_APPEND)
+			ret |= P9_OAPPEND;
+	}
+
+	return ret;
+}
+
+/**
+ * v9fs_blank_wstat - helper function to setup a 9P stat structure
+ * @v9ses: 9P session info (for determining extended mode)
+ * @wstat: structure to initialize
+ *
+ */
+
+static void
+v9fs_blank_wstat(struct p9_wstat *wstat)
+{
+	wstat->type = ~0;
+	wstat->dev = ~0;
+	wstat->qid.type = ~0;
+	wstat->qid.version = ~0;
+	*((long long *)&wstat->qid.path) = ~0;
+	wstat->mode = ~0;
+	wstat->atime = ~0;
+	wstat->mtime = ~0;
+	wstat->length = ~0;
+	wstat->name = NULL;
+	wstat->uid = NULL;
+	wstat->gid = NULL;
+	wstat->muid = NULL;
+	wstat->n_uid = ~0;
+	wstat->n_gid = ~0;
+	wstat->n_muid = ~0;
+	wstat->extension = NULL;
+}
+
+/**
+ * v9fs_get_inode - helper function to setup an inode
+ * @sb: superblock
+ * @mode: mode to setup inode with
+ *
+ */
+
+struct inode *v9fs_get_inode(struct super_block *sb, int mode)
+{
+	struct inode *inode;
+	struct v9fs_session_info *v9ses = sb->s_fs_info;
+
+	P9_DPRINTK(P9_DEBUG_VFS, "super block: %p mode: %o\n", sb, mode);
+
+	inode = new_inode(sb);
+	if (inode) {
+		inode->i_mode = mode;
+		inode->i_uid = current->fsuid;
+		inode->i_gid = current->fsgid;
+		inode->i_blocks = 0;
+		inode->i_rdev = 0;
+		inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+		inode->i_mapping->a_ops = &v9fs_addr_operations;
+
+		switch (mode & S_IFMT) {
+		case S_IFIFO:
+		case S_IFBLK:
+		case S_IFCHR:
+		case S_IFSOCK:
+			if (!v9fs_extended(v9ses)) {
+				P9_DPRINTK(P9_DEBUG_ERROR,
+				      "special files without extended mode\n");
+				return ERR_PTR(-EINVAL);
+			}
+			init_special_inode(inode, inode->i_mode,
+					   inode->i_rdev);
+			break;
+		case S_IFREG:
+			inode->i_op = &v9fs_file_inode_operations;
+			inode->i_fop = &v9fs_file_operations;
+			break;
+		case S_IFLNK:
+			if (!v9fs_extended(v9ses)) {
+				P9_DPRINTK(P9_DEBUG_ERROR,
+					"extended modes used w/o 9P2000.u\n");
+				return ERR_PTR(-EINVAL);
+			}
+			inode->i_op = &v9fs_symlink_inode_operations;
+			break;
+		case S_IFDIR:
+			inc_nlink(inode);
+			if (v9fs_extended(v9ses))
+				inode->i_op = &v9fs_dir_inode_operations_ext;
+			else
+				inode->i_op = &v9fs_dir_inode_operations;
+			inode->i_fop = &v9fs_dir_operations;
+			break;
+		default:
+			P9_DPRINTK(P9_DEBUG_ERROR,
+				"BAD mode 0x%x S_IFMT 0x%x\n",
+				mode, mode & S_IFMT);
+			return ERR_PTR(-EINVAL);
+		}
+	} else {
+		P9_EPRINTK(KERN_WARNING, "Problem allocating inode\n");
+		return ERR_PTR(-ENOMEM);
+	}
+	return inode;
+}
+
+/*
+static struct v9fs_fid*
+v9fs_clone_walk(struct v9fs_session_info *v9ses, u32 fid, struct dentry *dentry)
+{
+	int err;
+	int nfid;
+	struct v9fs_fid *ret;
+	struct v9fs_fcall *fcall;
+
+	nfid = v9fs_get_idpool(&v9ses->fidpool);
+	if (nfid < 0) {
+		eprintk(KERN_WARNING, "no free fids available\n");
+		return ERR_PTR(-ENOSPC);
+	}
+
+	err = v9fs_t_walk(v9ses, fid, nfid, (char *) dentry->d_name.name,
+		&fcall);
+
+	if (err < 0) {
+		if (fcall && fcall->id == RWALK)
+			goto clunk_fid;
+
+		PRINT_FCALL_ERROR("walk error", fcall);
+		v9fs_put_idpool(nfid, &v9ses->fidpool);
+		goto error;
+	}
+
+	kfree(fcall);
+	fcall = NULL;
+	ret = v9fs_fid_create(v9ses, nfid);
+	if (!ret) {
+		err = -ENOMEM;
+		goto clunk_fid;
+	}
+
+	err = v9fs_fid_insert(ret, dentry);
+	if (err < 0) {
+		v9fs_fid_destroy(ret);
+		goto clunk_fid;
+	}
+
+	return ret;
+
+clunk_fid:
+	v9fs_t_clunk(v9ses, nfid);
+
+error:
+	kfree(fcall);
+	return ERR_PTR(err);
+}
+*/
+
+/**
+ * v9fs_inode_from_fid - populate an inode by issuing a attribute request
+ * @v9ses: session information
+ * @fid: fid to issue attribute request for
+ * @sb: superblock on which to create inode
+ *
+ */
+
+static struct inode *
+v9fs_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
+	struct super_block *sb)
+{
+	int err, umode;
+	struct inode *ret;
+	struct p9_wstat *st;
+
+	ret = NULL;
+	st = p9_client_stat(fid);
+	if (IS_ERR(st)) {
+		err = PTR_ERR(st);
+		st = NULL;
+		goto error;
+	}
+
+	umode = p9mode2unixmode(v9ses, st->mode);
+	ret = v9fs_get_inode(sb, umode);
+	if (IS_ERR(ret)) {
+		err = PTR_ERR(ret);
+		ret = NULL;
+		goto error;
+	}
+
+	v9fs_stat2inode(st, ret, sb);
+	ret->i_ino = v9fs_qid2ino(&st->qid);
+	kfree(st);
+	return ret;
+
+error:
+	kfree(st);
+	if (ret)
+		iput(ret);
+
+	return ERR_PTR(err);
+}
+
+/**
+ * v9fs_remove - helper function to remove files and directories
+ * @dir: directory inode that is being deleted
+ * @file:  dentry that is being deleted
+ * @rmdir: removing a directory
+ *
+ */
+
+static int v9fs_remove(struct inode *dir, struct dentry *file, int rmdir)
+{
+	struct inode *file_inode;
+	struct v9fs_session_info *v9ses;
+	struct p9_fid *v9fid;
+
+	P9_DPRINTK(P9_DEBUG_VFS, "inode: %p dentry: %p rmdir: %d\n", dir, file,
+		rmdir);
+
+	file_inode = file->d_inode;
+	v9ses = v9fs_inode2v9ses(file_inode);
+	v9fid = v9fs_fid_clone(file);
+	if (IS_ERR(v9fid))
+		return PTR_ERR(v9fid);
+
+	return p9_client_remove(v9fid);
+}
+
+static int
+v9fs_open_created(struct inode *inode, struct file *file)
+{
+	return 0;
+}
+
+
+/**
+ * v9fs_create - Create a file
+ * @v9ses: session information
+ * @dir: directory that dentry is being created in
+ * @dentry:  dentry that is being created
+ * @perm: create permissions
+ * @mode: open mode
+ * @extension: 9p2000.u extension string to support devices, etc.
+ *
+ */
+static struct p9_fid *
+v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
+		struct dentry *dentry, char *extension, u32 perm, u8 mode)
+{
+	int err;
+	char *name;
+	struct p9_fid *dfid, *ofid, *fid;
+	struct inode *inode;
+
+	P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
+
+	err = 0;
+	ofid = NULL;
+	fid = NULL;
+	name = (char *) dentry->d_name.name;
+	dfid = v9fs_fid_clone(dentry->d_parent);
+	if (IS_ERR(dfid)) {
+		err = PTR_ERR(dfid);
+		P9_DPRINTK(P9_DEBUG_VFS, "fid clone failed %d\n", err);
+		dfid = NULL;
+		goto error;
+	}
+
+	/* clone a fid to use for creation */
+	ofid = p9_client_walk(dfid, 0, NULL, 1);
+	if (IS_ERR(ofid)) {
+		err = PTR_ERR(ofid);
+		P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
+		ofid = NULL;
+		goto error;
+	}
+
+	err = p9_client_fcreate(ofid, name, perm, mode, extension);
+	if (err < 0) {
+		P9_DPRINTK(P9_DEBUG_VFS, "p9_client_fcreate failed %d\n", err);
+		goto error;
+	}
+
+	/* now walk from the parent so we can get unopened fid */
+	fid = p9_client_walk(dfid, 1, &name, 0);
+	if (IS_ERR(fid)) {
+		err = PTR_ERR(fid);
+		P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
+		fid = NULL;
+		goto error;
+	} else
+		dfid = NULL;
+
+	/* instantiate inode and assign the unopened fid to the dentry */
+	inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb);
+	if (IS_ERR(inode)) {
+		err = PTR_ERR(inode);
+		P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n", err);
+		goto error;
+	}
+
+	if (v9ses->cache)
+		dentry->d_op = &v9fs_cached_dentry_operations;
+	else
+		dentry->d_op = &v9fs_dentry_operations;
+
+	d_instantiate(dentry, inode);
+	v9fs_fid_add(dentry, fid);
+	return ofid;
+
+error:
+	if (dfid)
+		p9_client_clunk(dfid);
+
+	if (ofid)
+		p9_client_clunk(ofid);
+
+	if (fid)
+		p9_client_clunk(fid);
+
+	return ERR_PTR(err);
+}
+
+/**
+ * v9fs_vfs_create - VFS hook to create files
+ * @dir: directory inode that is being created
+ * @dentry:  dentry that is being deleted
+ * @mode: create permissions
+ * @nd: path information
+ *
+ */
+
+static int
+v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode,
+		struct nameidata *nd)
+{
+	int err;
+	u32 perm;
+	int flags;
+	struct v9fs_session_info *v9ses;
+	struct p9_fid *fid;
+	struct file *filp;
+
+	err = 0;
+	fid = NULL;
+	v9ses = v9fs_inode2v9ses(dir);
+	perm = unixmode2p9mode(v9ses, mode);
+	if (nd && nd->flags & LOOKUP_OPEN)
+		flags = nd->intent.open.flags - 1;
+	else
+		flags = O_RDWR;
+
+	fid = v9fs_create(v9ses, dir, dentry, NULL, perm,
+				v9fs_uflags2omode(flags, v9fs_extended(v9ses)));
+	if (IS_ERR(fid)) {
+		err = PTR_ERR(fid);
+		fid = NULL;
+		goto error;
+	}
+
+	/* if we are opening a file, assign the open fid to the file */
+	if (nd && nd->flags & LOOKUP_OPEN) {
+		filp = lookup_instantiate_filp(nd, dentry, v9fs_open_created);
+		if (IS_ERR(filp)) {
+			err = PTR_ERR(filp);
+			goto error;
+		}
+
+		filp->private_data = fid;
+	} else
+		p9_client_clunk(fid);
+
+	return 0;
+
+error:
+	if (fid)
+		p9_client_clunk(fid);
+
+	return err;
+}
+
+/**
+ * v9fs_vfs_mkdir - VFS mkdir hook to create a directory
+ * @dir:  inode that is being unlinked
+ * @dentry: dentry that is being unlinked
+ * @mode: mode for new directory
+ *
+ */
+
+static int v9fs_vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
+{
+	int err;
+	u32 perm;
+	struct v9fs_session_info *v9ses;
+	struct p9_fid *fid;
+
+	P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
+	err = 0;
+	v9ses = v9fs_inode2v9ses(dir);
+	perm = unixmode2p9mode(v9ses, mode | S_IFDIR);
+	fid = v9fs_create(v9ses, dir, dentry, NULL, perm, P9_OREAD);
+	if (IS_ERR(fid)) {
+		err = PTR_ERR(fid);
+		fid = NULL;
+	}
+
+	if (fid)
+		p9_client_clunk(fid);
+
+	return err;
+}
+
+/**
+ * v9fs_vfs_lookup - VFS lookup hook to "walk" to a new inode
+ * @dir:  inode that is being walked from
+ * @dentry: dentry that is being walked to?
+ * @nameidata: path data
+ *
+ */
+
+static struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
+				      struct nameidata *nameidata)
+{
+	struct super_block *sb;
+	struct v9fs_session_info *v9ses;
+	struct p9_fid *dfid, *fid;
+	struct inode *inode;
+	char *name;
+	int result = 0;
+
+	P9_DPRINTK(P9_DEBUG_VFS, "dir: %p dentry: (%s) %p nameidata: %p\n",
+		dir, dentry->d_name.name, dentry, nameidata);
+
+	sb = dir->i_sb;
+	v9ses = v9fs_inode2v9ses(dir);
+	dfid = v9fs_fid_lookup(dentry->d_parent);
+	if (IS_ERR(dfid))
+		return ERR_CAST(dfid);
+
+	name = (char *) dentry->d_name.name;
+	fid = p9_client_walk(dfid, 1, &name, 1);
+	if (IS_ERR(fid)) {
+		result = PTR_ERR(fid);
+		if (result == -ENOENT) {
+			d_add(dentry, NULL);
+			return NULL;
+		}
+
+		return ERR_PTR(result);
+	}
+
+	inode = v9fs_inode_from_fid(v9ses, fid, dir->i_sb);
+	if (IS_ERR(inode)) {
+		result = PTR_ERR(inode);
+		inode = NULL;
+		goto error;
+	}
+
+	result = v9fs_fid_add(dentry, fid);
+	if (result < 0)
+		goto error;
+
+	if ((fid->qid.version) && (v9ses->cache))
+		dentry->d_op = &v9fs_cached_dentry_operations;
+	else
+		dentry->d_op = &v9fs_dentry_operations;
+
+	d_add(dentry, inode);
+	return NULL;
+
+error:
+	p9_client_clunk(fid);
+
+	return ERR_PTR(result);
+}
+
+/**
+ * v9fs_vfs_unlink - VFS unlink hook to delete an inode
+ * @i:  inode that is being unlinked
+ * @d: dentry that is being unlinked
+ *
+ */
+
+static int v9fs_vfs_unlink(struct inode *i, struct dentry *d)
+{
+	return v9fs_remove(i, d, 0);
+}
+
+/**
+ * v9fs_vfs_rmdir - VFS unlink hook to delete a directory
+ * @i:  inode that is being unlinked
+ * @d: dentry that is being unlinked
+ *
+ */
+
+static int v9fs_vfs_rmdir(struct inode *i, struct dentry *d)
+{
+	return v9fs_remove(i, d, 1);
+}
+
+/**
+ * v9fs_vfs_rename - VFS hook to rename an inode
+ * @old_dir:  old dir inode
+ * @old_dentry: old dentry
+ * @new_dir: new dir inode
+ * @new_dentry: new dentry
+ *
+ */
+
+static int
+v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
+		struct inode *new_dir, struct dentry *new_dentry)
+{
+	struct inode *old_inode;
+	struct v9fs_session_info *v9ses;
+	struct p9_fid *oldfid;
+	struct p9_fid *olddirfid;
+	struct p9_fid *newdirfid;
+	struct p9_wstat wstat;
+	int retval;
+
+	P9_DPRINTK(P9_DEBUG_VFS, "\n");
+	retval = 0;
+	old_inode = old_dentry->d_inode;
+	v9ses = v9fs_inode2v9ses(old_inode);
+	oldfid = v9fs_fid_lookup(old_dentry);
+	if (IS_ERR(oldfid))
+		return PTR_ERR(oldfid);
+
+	olddirfid = v9fs_fid_clone(old_dentry->d_parent);
+	if (IS_ERR(olddirfid)) {
+		retval = PTR_ERR(olddirfid);
+		goto done;
+	}
+
+	newdirfid = v9fs_fid_clone(new_dentry->d_parent);
+	if (IS_ERR(newdirfid)) {
+		retval = PTR_ERR(newdirfid);
+		goto clunk_olddir;
+	}
+
+	/* 9P can only handle file rename in the same directory */
+	if (memcmp(&olddirfid->qid, &newdirfid->qid, sizeof(newdirfid->qid))) {
+		P9_DPRINTK(P9_DEBUG_ERROR,
+				"old dir and new dir are different\n");
+		retval = -EXDEV;
+		goto clunk_newdir;
+	}
+
+	v9fs_blank_wstat(&wstat);
+	wstat.muid = v9ses->uname;
+	wstat.name = (char *) new_dentry->d_name.name;
+	retval = p9_client_wstat(oldfid, &wstat);
+
+clunk_newdir:
+	p9_client_clunk(newdirfid);
+
+clunk_olddir:
+	p9_client_clunk(olddirfid);
+
+done:
+	return retval;
+}
+
+/**
+ * v9fs_vfs_getattr - retrieve file metadata
+ * @mnt: mount information
+ * @dentry: file to get attributes on
+ * @stat: metadata structure to populate
+ *
+ */
+
+static int
+v9fs_vfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
+		 struct kstat *stat)
+{
+	int err;
+	struct v9fs_session_info *v9ses;
+	struct p9_fid *fid;
+	struct p9_wstat *st;
+
+	P9_DPRINTK(P9_DEBUG_VFS, "dentry: %p\n", dentry);
+	err = -EPERM;
+	v9ses = v9fs_inode2v9ses(dentry->d_inode);
+	if (v9ses->cache == CACHE_LOOSE)
+		return simple_getattr(mnt, dentry, stat);
+
+	fid = v9fs_fid_lookup(dentry);
+	if (IS_ERR(fid))
+		return PTR_ERR(fid);
+
+	st = p9_client_stat(fid);
+	if (IS_ERR(st))
+		return PTR_ERR(st);
+
+	v9fs_stat2inode(st, dentry->d_inode, dentry->d_inode->i_sb);
+		generic_fillattr(dentry->d_inode, stat);
+
+	kfree(st);
+	return 0;
+}
+
+/**
+ * v9fs_vfs_setattr - set file metadata
+ * @dentry: file whose metadata to set
+ * @iattr: metadata assignment structure
+ *
+ */
+
+static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
+{
+	int retval;
+	struct v9fs_session_info *v9ses;
+	struct p9_fid *fid;
+	struct p9_wstat wstat;
+
+	P9_DPRINTK(P9_DEBUG_VFS, "\n");
+	retval = -EPERM;
+	v9ses = v9fs_inode2v9ses(dentry->d_inode);
+	fid = v9fs_fid_lookup(dentry);
+	if(IS_ERR(fid))
+		return PTR_ERR(fid);
+
+	v9fs_blank_wstat(&wstat);
+	if (iattr->ia_valid & ATTR_MODE)
+		wstat.mode = unixmode2p9mode(v9ses, iattr->ia_mode);
+
+	if (iattr->ia_valid & ATTR_MTIME)
+		wstat.mtime = iattr->ia_mtime.tv_sec;
+
+	if (iattr->ia_valid & ATTR_ATIME)
+		wstat.atime = iattr->ia_atime.tv_sec;
+
+	if (iattr->ia_valid & ATTR_SIZE)
+		wstat.length = iattr->ia_size;
+
+	if (v9fs_extended(v9ses)) {
+		if (iattr->ia_valid & ATTR_UID)
+			wstat.n_uid = iattr->ia_uid;
+
+		if (iattr->ia_valid & ATTR_GID)
+			wstat.n_gid = iattr->ia_gid;
+	}
+
+	retval = p9_client_wstat(fid, &wstat);
+	if (retval >= 0)
+		retval = inode_setattr(dentry->d_inode, iattr);
+
+	return retval;
+}
+
+/**
+ * v9fs_stat2inode - populate an inode structure with mistat info
+ * @stat: Plan 9 metadata (mistat) structure
+ * @inode: inode to populate
+ * @sb: superblock of filesystem
+ *
+ */
+
+void
+v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode,
+	struct super_block *sb)
+{
+	char ext[32];
+	struct v9fs_session_info *v9ses = sb->s_fs_info;
+
+	inode->i_nlink = 1;
+
+	inode->i_atime.tv_sec = stat->atime;
+	inode->i_mtime.tv_sec = stat->mtime;
+	inode->i_ctime.tv_sec = stat->mtime;
+
+	inode->i_uid = v9ses->dfltuid;
+	inode->i_gid = v9ses->dfltgid;
+
+	if (v9fs_extended(v9ses)) {
+		inode->i_uid = stat->n_uid;
+		inode->i_gid = stat->n_gid;
+	}
+
+	inode->i_mode = p9mode2unixmode(v9ses, stat->mode);
+	if ((S_ISBLK(inode->i_mode)) || (S_ISCHR(inode->i_mode))) {
+		char type = 0;
+		int major = -1;
+		int minor = -1;
+
+		strncpy(ext, stat->extension, sizeof(ext));
+		sscanf(ext, "%c %u %u", &type, &major, &minor);
+		switch (type) {
+		case 'c':
+			inode->i_mode &= ~S_IFBLK;
+			inode->i_mode |= S_IFCHR;
+			break;
+		case 'b':
+			break;
+		default:
+			P9_DPRINTK(P9_DEBUG_ERROR,
+				"Unknown special type %c %s\n", type,
+				stat->extension);
+		};
+		inode->i_rdev = MKDEV(major, minor);
+		init_special_inode(inode, inode->i_mode, inode->i_rdev);
+	} else
+		inode->i_rdev = 0;
+
+	inode->i_size = stat->length;
+
+	/* not real number of blocks, but 512 byte ones ... */
+	inode->i_blocks = (inode->i_size + 512 - 1) >> 9;
+}
+
+/**
+ * v9fs_qid2ino - convert qid into inode number
+ * @qid: qid to hash
+ *
+ * BUG: potential for inode number collisions?
+ */
+
+ino_t v9fs_qid2ino(struct p9_qid *qid)
+{
+	u64 path = qid->path + 2;
+	ino_t i = 0;
+
+	if (sizeof(ino_t) == sizeof(path))
+		memcpy(&i, &path, sizeof(ino_t));
+	else
+		i = (ino_t) (path ^ (path >> 32));
+
+	return i;
+}
+
+/**
+ * v9fs_readlink - read a symlink's location (internal version)
+ * @dentry: dentry for symlink
+ * @buffer: buffer to load symlink location into
+ * @buflen: length of buffer
+ *
+ */
+
+static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen)
+{
+	int retval;
+
+	struct v9fs_session_info *v9ses;
+	struct p9_fid *fid;
+	struct p9_wstat *st;
+
+	P9_DPRINTK(P9_DEBUG_VFS, " %s\n", dentry->d_name.name);
+	retval = -EPERM;
+	v9ses = v9fs_inode2v9ses(dentry->d_inode);
+	fid = v9fs_fid_lookup(dentry);
+	if (IS_ERR(fid))
+		return PTR_ERR(fid);
+
+	if (!v9fs_extended(v9ses))
+		return -EBADF;
+
+	st = p9_client_stat(fid);
+	if (IS_ERR(st))
+		return PTR_ERR(st);
+
+	if (!(st->mode & P9_DMSYMLINK)) {
+		retval = -EINVAL;
+		goto done;
+	}
+
+	/* copy extension buffer into buffer */
+	strncpy(buffer, st->extension, buflen);
+
+	P9_DPRINTK(P9_DEBUG_VFS,
+		"%s -> %s (%s)\n", dentry->d_name.name, st->extension, buffer);
+
+	retval = buflen;
+
+done:
+	kfree(st);
+	return retval;
+}
+
+/**
+ * v9fs_vfs_readlink - read a symlink's location
+ * @dentry: dentry for symlink
+ * @buffer: buffer to load symlink location into
+ * @buflen: length of buffer
+ *
+ */
+
+static int v9fs_vfs_readlink(struct dentry *dentry, char __user * buffer,
+			     int buflen)
+{
+	int retval;
+	int ret;
+	char *link = __getname();
+
+	if (unlikely(!link))
+		return -ENOMEM;
+
+	if (buflen > PATH_MAX)
+		buflen = PATH_MAX;
+
+	P9_DPRINTK(P9_DEBUG_VFS, " dentry: %s (%p)\n", dentry->d_name.name,
+									dentry);
+
+	retval = v9fs_readlink(dentry, link, buflen);
+
+	if (retval > 0) {
+		if ((ret = copy_to_user(buffer, link, retval)) != 0) {
+			P9_DPRINTK(P9_DEBUG_ERROR,
+					"problem copying to user: %d\n", ret);
+			retval = ret;
+		}
+	}
+
+	__putname(link);
+	return retval;
+}
+
+/**
+ * v9fs_vfs_follow_link - follow a symlink path
+ * @dentry: dentry for symlink
+ * @nd: nameidata
+ *
+ */
+
+static void *v9fs_vfs_follow_link(struct dentry *dentry, struct nameidata *nd)
+{
+	int len = 0;
+	char *link = __getname();
+
+	P9_DPRINTK(P9_DEBUG_VFS, "%s n", dentry->d_name.name);
+
+	if (!link)
+		link = ERR_PTR(-ENOMEM);
+	else {
+		len = v9fs_readlink(dentry, link, PATH_MAX);
+
+		if (len < 0) {
+			__putname(link);
+			link = ERR_PTR(len);
+		} else
+			link[len] = 0;
+	}
+	nd_set_link(nd, link);
+
+	return NULL;
+}
+
+/**
+ * v9fs_vfs_put_link - release a symlink path
+ * @dentry: dentry for symlink
+ * @nd: nameidata
+ * @p: unused
+ *
+ */
+
+static void
+v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
+{
+	char *s = nd_get_link(nd);
+
+	P9_DPRINTK(P9_DEBUG_VFS, " %s %s\n", dentry->d_name.name,
+		IS_ERR(s) ? "<error>" : s);
+	if (!IS_ERR(s))
+		__putname(s);
+}
+
+/**
+ * v9fs_vfs_mkspecial - create a special file
+ * @dir: inode to create special file in
+ * @dentry: dentry to create
+ * @mode: mode to create special file
+ * @extension: 9p2000.u format extension string representing special file
+ *
+ */
+
+static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry,
+	int mode, const char *extension)
+{
+	u32 perm;
+	struct v9fs_session_info *v9ses;
+	struct p9_fid *fid;
+
+	v9ses = v9fs_inode2v9ses(dir);
+	if (!v9fs_extended(v9ses)) {
+		P9_DPRINTK(P9_DEBUG_ERROR, "not extended\n");
+		return -EPERM;
+	}
+
+	perm = unixmode2p9mode(v9ses, mode);
+	fid = v9fs_create(v9ses, dir, dentry, (char *) extension, perm,
+								P9_OREAD);
+	if (IS_ERR(fid))
+		return PTR_ERR(fid);
+
+	p9_client_clunk(fid);
+	return 0;
+}
+
+/**
+ * v9fs_vfs_symlink - helper function to create symlinks
+ * @dir: directory inode containing symlink
+ * @dentry: dentry for symlink
+ * @symname: symlink data
+ *
+ * See Also: 9P2000.u RFC for more information
+ *
+ */
+
+static int
+v9fs_vfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
+{
+	P9_DPRINTK(P9_DEBUG_VFS, " %lu,%s,%s\n", dir->i_ino,
+					dentry->d_name.name, symname);
+
+	return v9fs_vfs_mkspecial(dir, dentry, S_IFLNK, symname);
+}
+
+/**
+ * v9fs_vfs_link - create a hardlink
+ * @old_dentry: dentry for file to link to
+ * @dir: inode destination for new link
+ * @dentry: dentry for link
+ *
+ */
+
+static int
+v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir,
+	      struct dentry *dentry)
+{
+	int retval;
+	struct p9_fid *oldfid;
+	char *name;
+
+	P9_DPRINTK(P9_DEBUG_VFS,
+		" %lu,%s,%s\n", dir->i_ino, dentry->d_name.name,
+		old_dentry->d_name.name);
+
+	oldfid = v9fs_fid_clone(old_dentry);
+	if (IS_ERR(oldfid))
+		return PTR_ERR(oldfid);
+
+	name = __getname();
+	if (unlikely(!name)) {
+		retval = -ENOMEM;
+		goto clunk_fid;
+	}
+
+	sprintf(name, "%d\n", oldfid->fid);
+	retval = v9fs_vfs_mkspecial(dir, dentry, P9_DMLINK, name);
+	__putname(name);
+
+clunk_fid:
+	p9_client_clunk(oldfid);
+	return retval;
+}
+
+/**
+ * v9fs_vfs_mknod - create a special file
+ * @dir: inode destination for new link
+ * @dentry: dentry for file
+ * @mode: mode for creation
+ * @rdev: device associated with special file
+ *
+ */
+
+static int
+v9fs_vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
+{
+	int retval;
+	char *name;
+
+	P9_DPRINTK(P9_DEBUG_VFS,
+		" %lu,%s mode: %x MAJOR: %u MINOR: %u\n", dir->i_ino,
+		dentry->d_name.name, mode, MAJOR(rdev), MINOR(rdev));
+
+	if (!new_valid_dev(rdev))
+		return -EINVAL;
+
+	name = __getname();
+	if (!name)
+		return -ENOMEM;
+	/* build extension */
+	if (S_ISBLK(mode))
+		sprintf(name, "b %u %u", MAJOR(rdev), MINOR(rdev));
+	else if (S_ISCHR(mode))
+		sprintf(name, "c %u %u", MAJOR(rdev), MINOR(rdev));
+	else if (S_ISFIFO(mode))
+		*name = 0;
+	else {
+		__putname(name);
+		return -EINVAL;
+	}
+
+	retval = v9fs_vfs_mkspecial(dir, dentry, mode, name);
+	__putname(name);
+
+	return retval;
+}
+
+static const struct inode_operations v9fs_dir_inode_operations_ext = {
+	.create = v9fs_vfs_create,
+	.lookup = v9fs_vfs_lookup,
+	.symlink = v9fs_vfs_symlink,
+	.link = v9fs_vfs_link,
+	.unlink = v9fs_vfs_unlink,
+	.mkdir = v9fs_vfs_mkdir,
+	.rmdir = v9fs_vfs_rmdir,
+	.mknod = v9fs_vfs_mknod,
+	.rename = v9fs_vfs_rename,
+	.readlink = v9fs_vfs_readlink,
+	.getattr = v9fs_vfs_getattr,
+	.setattr = v9fs_vfs_setattr,
+};
+
+static const struct inode_operations v9fs_dir_inode_operations = {
+	.create = v9fs_vfs_create,
+	.lookup = v9fs_vfs_lookup,
+	.unlink = v9fs_vfs_unlink,
+	.mkdir = v9fs_vfs_mkdir,
+	.rmdir = v9fs_vfs_rmdir,
+	.mknod = v9fs_vfs_mknod,
+	.rename = v9fs_vfs_rename,
+	.getattr = v9fs_vfs_getattr,
+	.setattr = v9fs_vfs_setattr,
+};
+
+static const struct inode_operations v9fs_file_inode_operations = {
+	.getattr = v9fs_vfs_getattr,
+	.setattr = v9fs_vfs_setattr,
+};
+
+static const struct inode_operations v9fs_symlink_inode_operations = {
+	.readlink = v9fs_vfs_readlink,
+	.follow_link = v9fs_vfs_follow_link,
+	.put_link = v9fs_vfs_put_link,
+	.getattr = v9fs_vfs_getattr,
+	.setattr = v9fs_vfs_setattr,
+};
diff --git a/fs/9p/vfs_super.c b/fs/9p/vfs_super.c
new file mode 100644
index 0000000..d6cb1a0
--- /dev/null
+++ b/fs/9p/vfs_super.c
@@ -0,0 +1,249 @@
+/*
+ *  linux/fs/9p/vfs_super.c
+ *
+ * This file contians superblock ops for 9P2000. It is intended that
+ * you mount this file system on directories.
+ *
+ *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
+ *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
+ *
+ *  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/kernel.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/stat.h>
+#include <linux/string.h>
+#include <linux/inet.h>
+#include <linux/pagemap.h>
+#include <linux/seq_file.h>
+#include <linux/mount.h>
+#include <linux/idr.h>
+#include <linux/sched.h>
+#include <net/9p/9p.h>
+#include <net/9p/client.h>
+
+#include "v9fs.h"
+#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
+ *
+ */
+
+static int v9fs_set_super(struct super_block *s, void *data)
+{
+	s->s_fs_info = data;
+	return set_anon_super(s, data);
+}
+
+/**
+ * v9fs_fill_super - populate superblock with info
+ * @sb: superblock
+ * @v9ses: session information
+ * @flags: flags propagated from v9fs_get_sb()
+ *
+ */
+
+static void
+v9fs_fill_super(struct super_block *sb, struct v9fs_session_info *v9ses,
+		int flags)
+{
+	sb->s_maxbytes = MAX_LFS_FILESIZE;
+	sb->s_blocksize_bits = fls(v9ses->maxdata - 1);
+	sb->s_blocksize = 1 << sb->s_blocksize_bits;
+	sb->s_magic = V9FS_MAGIC;
+	sb->s_op = &v9fs_super_ops;
+
+	sb->s_flags = flags | MS_ACTIVE | MS_SYNCHRONOUS | MS_DIRSYNC |
+	    MS_NOATIME;
+}
+
+/**
+ * v9fs_get_sb - mount a superblock
+ * @fs_type: file system type
+ * @flags: mount flags
+ * @dev_name: device name that was mounted
+ * @data: mount options
+ * @mnt: mountpoint record to be instantiated
+ *
+ */
+
+static int v9fs_get_sb(struct file_system_type *fs_type, int flags,
+		       const char *dev_name, void *data,
+		       struct vfsmount *mnt)
+{
+	struct super_block *sb = NULL;
+	struct inode *inode = NULL;
+	struct dentry *root = NULL;
+	struct v9fs_session_info *v9ses = NULL;
+	struct p9_wstat *st = NULL;
+	int mode = S_IRWXUGO | S_ISVTX;
+	uid_t uid = current->fsuid;
+	gid_t gid = current->fsgid;
+	struct p9_fid *fid;
+	int retval = 0;
+
+	P9_DPRINTK(P9_DEBUG_VFS, " \n");
+
+	st = NULL;
+	v9ses = kzalloc(sizeof(struct v9fs_session_info), GFP_KERNEL);
+	if (!v9ses)
+		return -ENOMEM;
+
+	fid = v9fs_session_init(v9ses, dev_name, data);
+	if (IS_ERR(fid)) {
+		retval = PTR_ERR(fid);
+		goto close_session;
+	}
+
+	st = p9_client_stat(fid);
+	if (IS_ERR(st)) {
+		retval = PTR_ERR(st);
+		goto clunk_fid;
+	}
+
+	sb = sget(fs_type, NULL, v9fs_set_super, v9ses);
+	if (IS_ERR(sb)) {
+		retval = PTR_ERR(sb);
+		goto free_stat;
+	}
+	v9fs_fill_super(sb, v9ses, flags);
+
+	inode = v9fs_get_inode(sb, S_IFDIR | mode);
+	if (IS_ERR(inode)) {
+		retval = PTR_ERR(inode);
+		goto release_sb;
+	}
+
+	inode->i_uid = uid;
+	inode->i_gid = gid;
+
+	root = d_alloc_root(inode);
+	if (!root) {
+		retval = -ENOMEM;
+		goto release_sb;
+	}
+
+	sb->s_root = root;
+	root->d_inode->i_ino = v9fs_qid2ino(&st->qid);
+
+	v9fs_stat2inode(st, root->d_inode, sb);
+
+	v9fs_fid_add(root, fid);
+	p9stat_free(st);
+	kfree(st);
+
+P9_DPRINTK(P9_DEBUG_VFS, " return simple set mount\n");
+	return simple_set_mnt(mnt, sb);
+
+release_sb:
+	if (sb) {
+		up_write(&sb->s_umount);
+		deactivate_super(sb);
+	}
+
+free_stat:
+	kfree(st);
+
+clunk_fid:
+	p9_client_clunk(fid);
+
+close_session:
+	v9fs_session_close(v9ses);
+	kfree(v9ses);
+
+	return retval;
+}
+
+/**
+ * v9fs_kill_super - Kill Superblock
+ * @s: superblock
+ *
+ */
+
+static void v9fs_kill_super(struct super_block *s)
+{
+	struct v9fs_session_info *v9ses = s->s_fs_info;
+
+	P9_DPRINTK(P9_DEBUG_VFS, " %p\n", s);
+
+	v9fs_dentry_release(s->s_root);	/* clunk root */
+
+	kill_anon_super(s);
+
+	v9fs_session_close(v9ses);
+	kfree(v9ses);
+	P9_DPRINTK(P9_DEBUG_VFS, "exiting kill_super\n");
+}
+
+/**
+ * v9fs_show_options - Show mount options in /proc/mounts
+ * @m: seq_file to write to
+ * @mnt: mount descriptor
+ *
+ */
+
+static int v9fs_show_options(struct seq_file *m, struct vfsmount *mnt)
+{
+	struct v9fs_session_info *v9ses = mnt->mnt_sb->s_fs_info;
+
+	seq_printf(m, "%s", v9ses->options);
+	return 0;
+}
+
+static void
+v9fs_umount_begin(struct super_block *sb)
+{
+	struct v9fs_session_info *v9ses = sb->s_fs_info;
+
+	v9fs_session_cancel(v9ses);
+}
+
+static const struct super_operations v9fs_super_ops = {
+	.statfs = simple_statfs,
+	.clear_inode = v9fs_clear_inode,
+	.show_options = v9fs_show_options,
+	.umount_begin = v9fs_umount_begin,
+};
+
+struct file_system_type v9fs_fs_type = {
+	.name = "9p",
+	.get_sb = v9fs_get_sb,
+	.kill_sb = v9fs_kill_super,
+	.owner = THIS_MODULE,
+};