Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull more vfs stuff from Al Viro:
 "O_TMPFILE ABI changes, Oleg's fput() series, misc cleanups, including
  making simple_lookup() usable for filesystems with non-NULL s_d_op,
  which allows us to get rid of quite a bit of ugliness"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  sunrpc: now we can just set ->s_d_op
  cgroup: we can use simple_lookup() now
  efivarfs: we can use simple_lookup() now
  make simple_lookup() usable for filesystems that set ->s_d_op
  configfs: don't open-code d_alloc_name()
  __rpc_lookup_create_exclusive: pass string instead of qstr
  rpc_create_*_dir: don't bother with qstr
  llist: llist_add() can use llist_add_batch()
  llist: fix/simplify llist_add() and llist_add_batch()
  fput: turn "list_head delayed_fput_list" into llist_head
  fs/file_table.c:fput(): add comment
  Safer ABI for O_TMPFILE

18 files changed, 73 insertions, 137 deletions

diff --git a/arch/alpha/include/uapi/asm/fcntl.h b/arch/alpha/include/uapi/asm/fcntl.h
index dfdadb0..09f49a6 100644
--- a/arch/alpha/include/uapi/asm/fcntl.h
+++ b/arch/alpha/include/uapi/asm/fcntl.h
@@ -32,7 +32,7 @@
 #define O_SYNC		(__O_SYNC|O_DSYNC)
 
 #define O_PATH		040000000
-#define O_TMPFILE	0100000000
+#define __O_TMPFILE	0100000000
 
 #define F_GETLK		7
 #define F_SETLK		8
diff --git a/arch/parisc/include/uapi/asm/fcntl.h b/arch/parisc/include/uapi/asm/fcntl.h
index cc61c47..34a46cb 100644
--- a/arch/parisc/include/uapi/asm/fcntl.h
+++ b/arch/parisc/include/uapi/asm/fcntl.h
@@ -20,7 +20,7 @@
 #define O_INVISIBLE	004000000 /* invisible I/O, for DMAPI/XDSM */
 
 #define O_PATH		020000000
-#define O_TMPFILE	040000000
+#define __O_TMPFILE	040000000
 
 #define F_GETLK64	8
 #define F_SETLK64	9
diff --git a/arch/sparc/include/uapi/asm/fcntl.h b/arch/sparc/include/uapi/asm/fcntl.h
index d73e5e0..7e8ace5 100644
--- a/arch/sparc/include/uapi/asm/fcntl.h
+++ b/arch/sparc/include/uapi/asm/fcntl.h
@@ -35,7 +35,7 @@
 #define O_SYNC		(__O_SYNC|O_DSYNC)
 
 #define O_PATH		0x1000000
-#define O_TMPFILE	0x2000000
+#define __O_TMPFILE	0x2000000
 
 #define F_GETOWN	5	/*  for sockets. */
 #define F_SETOWN	6	/*  for sockets. */
diff --git a/fs/configfs/dir.c b/fs/configfs/dir.c
index 5e7c60c1..277bd1b 100644
--- a/fs/configfs/dir.c
+++ b/fs/configfs/dir.c
@@ -660,19 +660,15 @@ static int create_default_group(struct config_group *parent_group,
 				struct config_group *group)
 {
 	int ret;
-	struct qstr name;
 	struct configfs_dirent *sd;
 	/* We trust the caller holds a reference to parent */
 	struct dentry *child, *parent = parent_group->cg_item.ci_dentry;
 
 	if (!group->cg_item.ci_name)
 		group->cg_item.ci_name = group->cg_item.ci_namebuf;
-	name.name = group->cg_item.ci_name;
-	name.len = strlen(name.name);
-	name.hash = full_name_hash(name.name, name.len);
 
 	ret = -ENOMEM;
-	child = d_alloc(parent, &name);
+	child = d_alloc_name(parent, group->cg_item.ci_name);
 	if (child) {
 		d_add(child, NULL);
 
@@ -1650,7 +1646,6 @@ int configfs_register_subsystem(struct configfs_subsystem *subsys)
 {
 	int err;
 	struct config_group *group = &subsys->su_group;
-	struct qstr name;
 	struct dentry *dentry;
 	struct dentry *root;
 	struct configfs_dirent *sd;
@@ -1667,12 +1662,8 @@ int configfs_register_subsystem(struct configfs_subsystem *subsys)
 
 	mutex_lock_nested(&root->d_inode->i_mutex, I_MUTEX_PARENT);
 
-	name.name = group->cg_item.ci_name;
-	name.len = strlen(name.name);
-	name.hash = full_name_hash(name.name, name.len);
-
 	err = -ENOMEM;
-	dentry = d_alloc(root, &name);
+	dentry = d_alloc_name(root, group->cg_item.ci_name);
 	if (dentry) {
 		d_add(dentry, NULL);
 
diff --git a/fs/efivarfs/inode.c b/fs/efivarfs/inode.c
index 7e787fb..07ab497 100644
--- a/fs/efivarfs/inode.c
+++ b/fs/efivarfs/inode.c
@@ -155,20 +155,8 @@ static int efivarfs_unlink(struct inode *dir, struct dentry *dentry)
 	return 0;
 };
 
-/*
- * Handle negative dentry.
- */
-static struct dentry *efivarfs_lookup(struct inode *dir, struct dentry *dentry,
-				      unsigned int flags)
-{
-	if (dentry->d_name.len > NAME_MAX)
-		return ERR_PTR(-ENAMETOOLONG);
-	d_add(dentry, NULL);
-	return NULL;
-}
-
 const struct inode_operations efivarfs_dir_inode_operations = {
-	.lookup = efivarfs_lookup,
+	.lookup = simple_lookup,
 	.unlink = efivarfs_unlink,
 	.create = efivarfs_create,
 };
diff --git a/fs/file_table.c b/fs/file_table.c
index 08e719b..b44e4c5 100644
--- a/fs/file_table.c
+++ b/fs/file_table.c
@@ -265,18 +265,15 @@ static void __fput(struct file *file)
 	mntput(mnt);
 }
 
-static DEFINE_SPINLOCK(delayed_fput_lock);
-static LIST_HEAD(delayed_fput_list);
+static LLIST_HEAD(delayed_fput_list);
 static void delayed_fput(struct work_struct *unused)
 {
-	LIST_HEAD(head);
-	spin_lock_irq(&delayed_fput_lock);
-	list_splice_init(&delayed_fput_list, &head);
-	spin_unlock_irq(&delayed_fput_lock);
-	while (!list_empty(&head)) {
-		struct file *f = list_first_entry(&head, struct file, f_u.fu_list);
-		list_del_init(&f->f_u.fu_list);
-		__fput(f);
+	struct llist_node *node = llist_del_all(&delayed_fput_list);
+	struct llist_node *next;
+
+	for (; node; node = next) {
+		next = llist_next(node);
+		__fput(llist_entry(node, struct file, f_u.fu_llist));
 	}
 }
 
@@ -306,18 +303,22 @@ void fput(struct file *file)
 {
 	if (atomic_long_dec_and_test(&file->f_count)) {
 		struct task_struct *task = current;
-		unsigned long flags;
 
 		file_sb_list_del(file);
 		if (likely(!in_interrupt() && !(task->flags & PF_KTHREAD))) {
 			init_task_work(&file->f_u.fu_rcuhead, ____fput);
 			if (!task_work_add(task, &file->f_u.fu_rcuhead, true))
 				return;
+			/*
+			 * After this task has run exit_task_work(),
+			 * task_work_add() will fail.  free_ipc_ns()->
+			 * shm_destroy() can do this.  Fall through to delayed
+			 * fput to avoid leaking *file.
+			 */
 		}
-		spin_lock_irqsave(&delayed_fput_lock, flags);
-		list_add(&file->f_u.fu_list, &delayed_fput_list);
-		schedule_work(&delayed_fput_work);
-		spin_unlock_irqrestore(&delayed_fput_lock, flags);
+
+		if (llist_add(&file->f_u.fu_llist, &delayed_fput_list))
+			schedule_work(&delayed_fput_work);
 	}
 }
 
diff --git a/fs/libfs.c b/fs/libfs.c
index c3a0837..3a3a9b5 100644
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -61,7 +61,8 @@ struct dentry *simple_lookup(struct inode *dir, struct dentry *dentry, unsigned
 
 	if (dentry->d_name.len > NAME_MAX)
 		return ERR_PTR(-ENAMETOOLONG);
-	d_set_d_op(dentry, &simple_dentry_operations);
+	if (!dentry->d_sb->s_d_op)
+		d_set_d_op(dentry, &simple_dentry_operations);
 	d_add(dentry, NULL);
 	return NULL;
 }
diff --git a/fs/namei.c b/fs/namei.c
index b2beee7..8b61d10 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2977,7 +2977,7 @@ static struct file *path_openat(int dfd, struct filename *pathname,
 
 	file->f_flags = op->open_flag;
 
-	if (unlikely(file->f_flags & O_TMPFILE)) {
+	if (unlikely(file->f_flags & __O_TMPFILE)) {
 		error = do_tmpfile(dfd, pathname, nd, flags, op, file, &opened);
 		goto out;
 	}
diff --git a/fs/open.c b/fs/open.c
index fca72c4..9156cb0 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -840,8 +840,8 @@ static inline int build_open_flags(int flags, umode_t mode, struct open_flags *o
 	if (flags & __O_SYNC)
 		flags |= O_DSYNC;
 
-	if (flags & O_TMPFILE) {
-		if (!(flags & O_CREAT))
+	if (flags & __O_TMPFILE) {
+		if ((flags & O_TMPFILE_MASK) != O_TMPFILE)
 			return -EINVAL;
 		acc_mode = MAY_OPEN | ACC_MODE(flags);
 	} else if (flags & O_PATH) {
diff --git a/include/linux/fs.h b/include/linux/fs.h
index a35b10e..9818747 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -10,6 +10,7 @@
 #include <linux/stat.h>
 #include <linux/cache.h>
 #include <linux/list.h>
+#include <linux/llist.h>
 #include <linux/radix-tree.h>
 #include <linux/rbtree.h>
 #include <linux/init.h>
@@ -768,6 +769,7 @@ struct file {
 	 */
 	union {
 		struct list_head	fu_list;
+		struct llist_node	fu_llist;
 		struct rcu_head 	fu_rcuhead;
 	} f_u;
 	struct path		f_path;
diff --git a/include/linux/llist.h b/include/linux/llist.h
index a5199f6..cdaa7f0 100644
--- a/include/linux/llist.h
+++ b/include/linux/llist.h
@@ -142,6 +142,9 @@ static inline struct llist_node *llist_next(struct llist_node *node)
 	return node->next;
 }
 
+extern bool llist_add_batch(struct llist_node *new_first,
+			    struct llist_node *new_last,
+			    struct llist_head *head);
 /**
  * llist_add - add a new entry
  * @new:	new entry to be added
@@ -151,18 +154,7 @@ static inline struct llist_node *llist_next(struct llist_node *node)
  */
 static inline bool llist_add(struct llist_node *new, struct llist_head *head)
 {
-	struct llist_node *entry, *old_entry;
-
-	entry = head->first;
-	for (;;) {
-		old_entry = entry;
-		new->next = entry;
-		entry = cmpxchg(&head->first, old_entry, new);
-		if (entry == old_entry)
-			break;
-	}
-
-	return old_entry == NULL;
+	return llist_add_batch(new, new, head);
 }
 
 /**
@@ -178,9 +170,6 @@ static inline struct llist_node *llist_del_all(struct llist_head *head)
 	return xchg(&head->first, NULL);
 }
 
-extern bool llist_add_batch(struct llist_node *new_first,
-			    struct llist_node *new_last,
-			    struct llist_head *head);
 extern struct llist_node *llist_del_first(struct llist_head *head);
 
 #endif /* LLIST_H */
diff --git a/include/linux/sunrpc/rpc_pipe_fs.h b/include/linux/sunrpc/rpc_pipe_fs.h
index a7b422b..aa5b582 100644
--- a/include/linux/sunrpc/rpc_pipe_fs.h
+++ b/include/linux/sunrpc/rpc_pipe_fs.h
@@ -73,12 +73,12 @@ extern ssize_t rpc_pipe_generic_upcall(struct file *, struct rpc_pipe_msg *,
 extern int rpc_queue_upcall(struct rpc_pipe *, struct rpc_pipe_msg *);
 
 struct rpc_clnt;
-extern struct dentry *rpc_create_client_dir(struct dentry *, struct qstr *, struct rpc_clnt *);
+extern struct dentry *rpc_create_client_dir(struct dentry *, const char *, struct rpc_clnt *);
 extern int rpc_remove_client_dir(struct dentry *);
 
 struct cache_detail;
 extern struct dentry *rpc_create_cache_dir(struct dentry *,
-					   struct qstr *,
+					   const char *,
 					   umode_t umode,
 					   struct cache_detail *);
 extern void rpc_remove_cache_dir(struct dentry *);
diff --git a/include/uapi/asm-generic/fcntl.h b/include/uapi/asm-generic/fcntl.h
index 06632be..05ac354 100644
--- a/include/uapi/asm-generic/fcntl.h
+++ b/include/uapi/asm-generic/fcntl.h
@@ -84,10 +84,14 @@
 #define O_PATH		010000000
 #endif
 
-#ifndef O_TMPFILE
-#define O_TMPFILE	020000000
+#ifndef __O_TMPFILE
+#define __O_TMPFILE	020000000
 #endif
 
+/* a horrid kludge trying to make sure that this will fail on old kernels */
+#define O_TMPFILE (__O_TMPFILE | O_DIRECTORY | O_RDWR)
+#define O_TMPFILE_MASK (__O_TMPFILE | O_DIRECTORY | O_CREAT | O_ACCMODE)      
+
 #ifndef O_NDELAY
 #define O_NDELAY	O_NONBLOCK
 #endif
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index e5583d1..0e0b20b 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -802,7 +802,6 @@ static struct cgroup *task_cgroup_from_root(struct task_struct *task,
  */
 
 static int cgroup_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode);
-static struct dentry *cgroup_lookup(struct inode *, struct dentry *, unsigned int);
 static int cgroup_rmdir(struct inode *unused_dir, struct dentry *dentry);
 static int cgroup_populate_dir(struct cgroup *cgrp, bool base_files,
 			       unsigned long subsys_mask);
@@ -2642,7 +2641,7 @@ static const struct inode_operations cgroup_file_inode_operations = {
 };
 
 static const struct inode_operations cgroup_dir_inode_operations = {
-	.lookup = cgroup_lookup,
+	.lookup = simple_lookup,
 	.mkdir = cgroup_mkdir,
 	.rmdir = cgroup_rmdir,
 	.rename = cgroup_rename,
@@ -2652,14 +2651,6 @@ static const struct inode_operations cgroup_dir_inode_operations = {
 	.removexattr = cgroup_removexattr,
 };
 
-static struct dentry *cgroup_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
-{
-	if (dentry->d_name.len > NAME_MAX)
-		return ERR_PTR(-ENAMETOOLONG);
-	d_add(dentry, NULL);
-	return NULL;
-}
-
 /*
  * Check if a file is a control file
  */
diff --git a/lib/llist.c b/lib/llist.c
index 4a15115..4a70d12 100644
--- a/lib/llist.c
+++ b/lib/llist.c
@@ -39,18 +39,13 @@
 bool llist_add_batch(struct llist_node *new_first, struct llist_node *new_last,
 		     struct llist_head *head)
 {
-	struct llist_node *entry, *old_entry;
+	struct llist_node *first;
 
-	entry = head->first;
-	for (;;) {
-		old_entry = entry;
-		new_last->next = entry;
-		entry = cmpxchg(&head->first, old_entry, new_first);
-		if (entry == old_entry)
-			break;
-	}
+	do {
+		new_last->next = first = ACCESS_ONCE(head->first);
+	} while (cmpxchg(&head->first, first, new_first) != first);
 
-	return old_entry == NULL;
+	return !first;
 }
 EXPORT_SYMBOL_GPL(llist_add_batch);
 
diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c
index 49eb370..a72de07 100644
--- a/net/sunrpc/cache.c
+++ b/net/sunrpc/cache.c
@@ -1823,19 +1823,11 @@ int sunrpc_cache_register_pipefs(struct dentry *parent,
 				 const char *name, umode_t umode,
 				 struct cache_detail *cd)
 {
-	struct qstr q;
-	struct dentry *dir;
-	int ret = 0;
-
-	q.name = name;
-	q.len = strlen(name);
-	q.hash = full_name_hash(q.name, q.len);
-	dir = rpc_create_cache_dir(parent, &q, umode, cd);
-	if (!IS_ERR(dir))
-		cd->u.pipefs.dir = dir;
-	else
-		ret = PTR_ERR(dir);
-	return ret;
+	struct dentry *dir = rpc_create_cache_dir(parent, name, umode, cd);
+	if (IS_ERR(dir))
+		return PTR_ERR(dir);
+	cd->u.pipefs.dir = dir;
+	return 0;
 }
 EXPORT_SYMBOL_GPL(sunrpc_cache_register_pipefs);
 
diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index aa40156..9963584 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -128,9 +128,7 @@ static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb,
 {
 	static uint32_t clntid;
 	char name[15];
-	struct qstr q = { .name = name };
 	struct dentry *dir, *dentry;
-	int error;
 
 	dir = rpc_d_lookup_sb(sb, dir_name);
 	if (dir == NULL) {
@@ -138,19 +136,17 @@ static struct dentry *rpc_setup_pipedir_sb(struct super_block *sb,
 		return dir;
 	}
 	for (;;) {
-		q.len = snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++);
+		snprintf(name, sizeof(name), "clnt%x", (unsigned int)clntid++);
 		name[sizeof(name) - 1] = '\0';
-		q.hash = full_name_hash(q.name, q.len);
-		dentry = rpc_create_client_dir(dir, &q, clnt);
+		dentry = rpc_create_client_dir(dir, name, clnt);
 		if (!IS_ERR(dentry))
 			break;
-		error = PTR_ERR(dentry);
-		if (error != -EEXIST) {
-			printk(KERN_INFO "RPC: Couldn't create pipefs entry"
-					" %s/%s, error %d\n",
-					dir_name, name, error);
-			break;
-		}
+		if (dentry == ERR_PTR(-EEXIST))
+			continue;
+		printk(KERN_INFO "RPC: Couldn't create pipefs entry"
+				" %s/%s, error %ld\n",
+				dir_name, name, PTR_ERR(dentry));
+		break;
 	}
 	dput(dir);
 	return dentry;
diff --git a/net/sunrpc/rpc_pipe.c b/net/sunrpc/rpc_pipe.c
index 61239a2..406859c 100644
--- a/net/sunrpc/rpc_pipe.c
+++ b/net/sunrpc/rpc_pipe.c
@@ -673,13 +673,12 @@ static int __rpc_rmpipe(struct inode *dir, struct dentry *dentry)
 }
 
 static struct dentry *__rpc_lookup_create_exclusive(struct dentry *parent,
-					  struct qstr *name)
+					  const char *name)
 {
-	struct dentry *dentry;
-
-	dentry = d_lookup(parent, name);
+	struct qstr q = QSTR_INIT(name, strlen(name));
+	struct dentry *dentry = d_hash_and_lookup(parent, &q);
 	if (!dentry) {
-		dentry = d_alloc(parent, name);
+		dentry = d_alloc(parent, &q);
 		if (!dentry)
 			return ERR_PTR(-ENOMEM);
 	}
@@ -704,8 +703,7 @@ static void __rpc_depopulate(struct dentry *parent,
 	for (i = start; i < eof; i++) {
 		name.name = files[i].name;
 		name.len = strlen(files[i].name);
-		name.hash = full_name_hash(name.name, name.len);
-		dentry = d_lookup(parent, &name);
+		dentry = d_hash_and_lookup(parent, &name);
 
 		if (dentry == NULL)
 			continue;
@@ -747,12 +745,7 @@ static int rpc_populate(struct dentry *parent,
 
 	mutex_lock(&dir->i_mutex);
 	for (i = start; i < eof; i++) {
-		struct qstr q;
-
-		q.name = files[i].name;
-		q.len = strlen(files[i].name);
-		q.hash = full_name_hash(q.name, q.len);
-		dentry = __rpc_lookup_create_exclusive(parent, &q);
+		dentry = __rpc_lookup_create_exclusive(parent, files[i].name);
 		err = PTR_ERR(dentry);
 		if (IS_ERR(dentry))
 			goto out_bad;
@@ -785,7 +778,7 @@ out_bad:
 }
 
 static struct dentry *rpc_mkdir_populate(struct dentry *parent,
-		struct qstr *name, umode_t mode, void *private,
+		const char *name, umode_t mode, void *private,
 		int (*populate)(struct dentry *, void *), void *args_populate)
 {
 	struct dentry *dentry;
@@ -856,7 +849,6 @@ struct dentry *rpc_mkpipe_dentry(struct dentry *parent, const char *name,
 	struct dentry *dentry;
 	struct inode *dir = parent->d_inode;
 	umode_t umode = S_IFIFO | S_IRUSR | S_IWUSR;
-	struct qstr q;
 	int err;
 
 	if (pipe->ops->upcall == NULL)
@@ -864,12 +856,8 @@ struct dentry *rpc_mkpipe_dentry(struct dentry *parent, const char *name,
 	if (pipe->ops->downcall == NULL)
 		umode &= ~S_IWUGO;
 
-	q.name = name;
-	q.len = strlen(name);
-	q.hash = full_name_hash(q.name, q.len),
-
 	mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
-	dentry = __rpc_lookup_create_exclusive(parent, &q);
+	dentry = __rpc_lookup_create_exclusive(parent, name);
 	if (IS_ERR(dentry))
 		goto out;
 	err = __rpc_mkpipe_dentry(dir, dentry, umode, &rpc_pipe_fops,
@@ -940,8 +928,8 @@ static void rpc_clntdir_depopulate(struct dentry *dentry)
 
 /**
  * rpc_create_client_dir - Create a new rpc_client directory in rpc_pipefs
- * @dentry: dentry from the rpc_pipefs root to the new directory
- * @name: &struct qstr for the name
+ * @dentry: the parent of new directory
+ * @name: the name of new directory
  * @rpc_client: rpc client to associate with this directory
  *
  * This creates a directory at the given @path associated with
@@ -950,7 +938,7 @@ static void rpc_clntdir_depopulate(struct dentry *dentry)
  * later be created using rpc_mkpipe().
  */
 struct dentry *rpc_create_client_dir(struct dentry *dentry,
-				   struct qstr *name,
+				   const char *name,
 				   struct rpc_clnt *rpc_client)
 {
 	return rpc_mkdir_populate(dentry, name, S_IRUGO | S_IXUGO, NULL,
@@ -996,7 +984,7 @@ static void rpc_cachedir_depopulate(struct dentry *dentry)
 	rpc_depopulate(dentry, cache_pipefs_files, 0, 3);
 }
 
-struct dentry *rpc_create_cache_dir(struct dentry *parent, struct qstr *name,
+struct dentry *rpc_create_cache_dir(struct dentry *parent, const char *name,
 				    umode_t umode, struct cache_detail *cd)
 {
 	return rpc_mkdir_populate(parent, name, umode, NULL,
@@ -1076,9 +1064,7 @@ struct dentry *rpc_d_lookup_sb(const struct super_block *sb,
 			       const unsigned char *dir_name)
 {
 	struct qstr dir = QSTR_INIT(dir_name, strlen(dir_name));
-
-	dir.hash = full_name_hash(dir.name, dir.len);
-	return d_lookup(sb->s_root, &dir);
+	return d_hash_and_lookup(sb->s_root, &dir);
 }
 EXPORT_SYMBOL_GPL(rpc_d_lookup_sb);