switch alloc_file() to passing struct path

... and have the caller grab both mnt and dentry; kill
leak in infiniband, while we are at it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

11 files changed, 78 insertions, 63 deletions

diff --git a/arch/ia64/kernel/perfmon.c b/arch/ia64/kernel/perfmon.c
index 599b233bef7..5246285a95f 100644
--- a/arch/ia64/kernel/perfmon.c
+++ b/arch/ia64/kernel/perfmon.c
@@ -2200,7 +2200,7 @@ pfm_alloc_file(pfm_context_t *ctx)
 {
 	struct file *file;
 	struct inode *inode;
-	struct dentry *dentry;
+	struct path path;
 	char name[32];
 	struct qstr this;
 
@@ -2225,18 +2225,19 @@ pfm_alloc_file(pfm_context_t *ctx)
 	/*
 	 * allocate a new dcache entry
 	 */
-	dentry = d_alloc(pfmfs_mnt->mnt_sb->s_root, &this);
-	if (!dentry) {
+	path.dentry = d_alloc(pfmfs_mnt->mnt_sb->s_root, &this);
+	if (!path.dentry) {
 		iput(inode);
 		return ERR_PTR(-ENOMEM);
 	}
+	path.mnt = mntget(pfmfs_mnt);
 
-	dentry->d_op = &pfmfs_dentry_operations;
-	d_add(dentry, inode);
+	path.dentry->d_op = &pfmfs_dentry_operations;
+	d_add(path.dentry, inode);
 
-	file = alloc_file(pfmfs_mnt, dentry, FMODE_READ, &pfm_file_ops);
+	file = alloc_file(&path, FMODE_READ, &pfm_file_ops);
 	if (!file) {
-		dput(dentry);
+		path_put(&path);
 		return ERR_PTR(-ENFILE);
 	}
 
diff --git a/drivers/infiniband/core/uverbs_main.c b/drivers/infiniband/core/uverbs_main.c
index aec0fbdfe7f..5f284ffd430 100644
--- a/drivers/infiniband/core/uverbs_main.c
+++ b/drivers/infiniband/core/uverbs_main.c
@@ -492,6 +492,7 @@ struct file *ib_uverbs_alloc_event_file(struct ib_uverbs_file *uverbs_file,
 					int is_async, int *fd)
 {
 	struct ib_uverbs_event_file *ev_file;
+	struct path path;
 	struct file *filp;
 	int ret;
 
@@ -519,8 +520,10 @@ struct file *ib_uverbs_alloc_event_file(struct ib_uverbs_file *uverbs_file,
 	 * system call on a uverbs file, which will already have a
 	 * module reference.
 	 */
-	filp = alloc_file(uverbs_event_mnt, dget(uverbs_event_mnt->mnt_root),
-			  FMODE_READ, fops_get(&uverbs_event_fops));
+	path.mnt = uverbs_event_mnt;
+	path.dentry = uverbs_event_mnt->mnt_root;
+	path_get(&path);
+	filp = alloc_file(&path, FMODE_READ, fops_get(&uverbs_event_fops));
 	if (!filp) {
 		ret = -ENFILE;
 		goto err_fd;
@@ -531,6 +534,8 @@ struct file *ib_uverbs_alloc_event_file(struct ib_uverbs_file *uverbs_file,
 	return filp;
 
 err_fd:
+	fops_put(&uverbs_event_fops);
+	path_put(&path);
 	put_unused_fd(*fd);
 
 err:
diff --git a/fs/anon_inodes.c b/fs/anon_inodes.c
index 2ca7a7cafdb..94f5110c465 100644
--- a/fs/anon_inodes.c
+++ b/fs/anon_inodes.c
@@ -88,7 +88,7 @@ struct file *anon_inode_getfile(const char *name,
 				void *priv, int flags)
 {
 	struct qstr this;
-	struct dentry *dentry;
+	struct path path;
 	struct file *file;
 	int error;
 
@@ -106,10 +106,11 @@ struct file *anon_inode_getfile(const char *name,
 	this.name = name;
 	this.len = strlen(name);
 	this.hash = 0;
-	dentry = d_alloc(anon_inode_mnt->mnt_sb->s_root, &this);
-	if (!dentry)
+	path.dentry = d_alloc(anon_inode_mnt->mnt_sb->s_root, &this);
+	if (!path.dentry)
 		goto err_module;
 
+	path.mnt = mntget(anon_inode_mnt);
 	/*
 	 * We know the anon_inode inode count is always greater than zero,
 	 * so we can avoid doing an igrab() and we can use an open-coded
@@ -117,14 +118,13 @@ struct file *anon_inode_getfile(const char *name,
 	 */
 	atomic_inc(&anon_inode_inode->i_count);
 
-	dentry->d_op = &anon_inodefs_dentry_operations;
+	path.dentry->d_op = &anon_inodefs_dentry_operations;
 	/* Do not publish this dentry inside the global dentry hash table */
-	dentry->d_flags &= ~DCACHE_UNHASHED;
-	d_instantiate(dentry, anon_inode_inode);
+	path.dentry->d_flags &= ~DCACHE_UNHASHED;
+	d_instantiate(path.dentry, anon_inode_inode);
 
 	error = -ENFILE;
-	file = alloc_file(anon_inode_mnt, dentry,
-			  FMODE_READ | FMODE_WRITE, fops);
+	file = alloc_file(&path, FMODE_READ | FMODE_WRITE, fops);
 	if (!file)
 		goto err_dput;
 	file->f_mapping = anon_inode_inode->i_mapping;
@@ -137,7 +137,7 @@ struct file *anon_inode_getfile(const char *name,
 	return file;
 
 err_dput:
-	dput(dentry);
+	path_put(&path);
 err_module:
 	module_put(fops->owner);
 	return ERR_PTR(error);
diff --git a/fs/file_table.c b/fs/file_table.c
index 602a9ee3023..163cd28314e 100644
--- a/fs/file_table.c
+++ b/fs/file_table.c
@@ -162,8 +162,8 @@ fail:
  * If all the callers of init_file() are eliminated, its
  * code should be moved into this function.
  */
-struct file *alloc_file(struct vfsmount *mnt, struct dentry *dentry,
-		fmode_t mode, const struct file_operations *fop)
+struct file *alloc_file(struct path *path, fmode_t mode,
+		const struct file_operations *fop)
 {
 	struct file *file;
 
@@ -171,9 +171,8 @@ struct file *alloc_file(struct vfsmount *mnt, struct dentry *dentry,
 	if (!file)
 		return NULL;
 
-	file->f_path.dentry = dentry;
-	file->f_path.mnt = mntget(mnt);
-	file->f_mapping = dentry->d_inode->i_mapping;
+	file->f_path = *path;
+	file->f_mapping = path->dentry->d_inode->i_mapping;
 	file->f_mode = mode;
 	file->f_op = fop;
 
@@ -183,10 +182,10 @@ struct file *alloc_file(struct vfsmount *mnt, struct dentry *dentry,
 	 * visible.  We do this for consistency, and so
 	 * that we can do debugging checks at __fput()
 	 */
-	if ((mode & FMODE_WRITE) && !special_file(dentry->d_inode->i_mode)) {
+	if ((mode & FMODE_WRITE) && !special_file(path->dentry->d_inode->i_mode)) {
 		int error = 0;
 		file_take_write(file);
-		error = mnt_clone_write(mnt);
+		error = mnt_clone_write(path->mnt);
 		WARN_ON(error);
 	}
 	return file;
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index 87a1258953b..6bd41525cd7 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -922,7 +922,8 @@ struct file *hugetlb_file_setup(const char *name, size_t size, int acctflag,
 	int error = -ENOMEM;
 	struct file *file;
 	struct inode *inode;
-	struct dentry *dentry, *root;
+	struct path path;
+	struct dentry *root;
 	struct qstr quick_string;
 
 	*user = NULL;
@@ -944,10 +945,11 @@ struct file *hugetlb_file_setup(const char *name, size_t size, int acctflag,
 	quick_string.name = name;
 	quick_string.len = strlen(quick_string.name);
 	quick_string.hash = 0;
-	dentry = d_alloc(root, &quick_string);
-	if (!dentry)
+	path.dentry = d_alloc(root, &quick_string);
+	if (!path.dentry)
 		goto out_shm_unlock;
 
+	path.mnt = mntget(hugetlbfs_vfsmount);
 	error = -ENOSPC;
 	inode = hugetlbfs_get_inode(root->d_sb, current_fsuid(),
 				current_fsgid(), S_IFREG | S_IRWXUGO, 0);
@@ -960,13 +962,12 @@ struct file *hugetlb_file_setup(const char *name, size_t size, int acctflag,
 			acctflag))
 		goto out_inode;
 
-	d_instantiate(dentry, inode);
+	d_instantiate(path.dentry, inode);
 	inode->i_size = size;
 	inode->i_nlink = 0;
 
 	error = -ENFILE;
-	file = alloc_file(hugetlbfs_vfsmount, dentry,
-			FMODE_WRITE | FMODE_READ,
+	file = alloc_file(&path, FMODE_WRITE | FMODE_READ,
 			&hugetlbfs_file_operations);
 	if (!file)
 		goto out_dentry; /* inode is already attached */
@@ -977,7 +978,7 @@ struct file *hugetlb_file_setup(const char *name, size_t size, int acctflag,
 out_inode:
 	iput(inode);
 out_dentry:
-	dput(dentry);
+	path_put(&path);
 out_shm_unlock:
 	if (*user) {
 		user_shm_unlock(size, *user);
diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index 9e4f90042ea..8271cf05c95 100644
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -646,6 +646,7 @@ SYSCALL_DEFINE1(inotify_init1, int, flags)
 	struct fsnotify_group *group;
 	struct user_struct *user;
 	struct file *filp;
+	struct path path;
 	int fd, ret;
 
 	/* Check the IN_* constants for consistency.  */
@@ -675,8 +676,10 @@ SYSCALL_DEFINE1(inotify_init1, int, flags)
 
 	atomic_inc(&user->inotify_devs);
 
-	filp = alloc_file(inotify_mnt, dget(inotify_mnt->mnt_root),
-			  FMODE_READ, &inotify_fops);
+	path.mnt = inotify_mnt;
+	path.dentry = inotify_mnt->mnt_root;
+	path_get(&path);
+	filp = alloc_file(&path, FMODE_READ, &inotify_fops);
 	if (!filp)
 		goto Enfile;
 
@@ -689,6 +692,7 @@ SYSCALL_DEFINE1(inotify_init1, int, flags)
 
 Enfile:
 	ret = -ENFILE;
+	path_put(&path);
 	atomic_dec(&user->inotify_devs);
 out_free_uid:
 	free_uid(user);
diff --git a/fs/pipe.c b/fs/pipe.c
index ae17d026aaa..81288bc2bcb 100644
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -974,7 +974,7 @@ struct file *create_write_pipe(int flags)
 	int err;
 	struct inode *inode;
 	struct file *f;
-	struct dentry *dentry;
+	struct path path;
 	struct qstr name = { .name = "" };
 
 	err = -ENFILE;
@@ -983,21 +983,22 @@ struct file *create_write_pipe(int flags)
 		goto err;
 
 	err = -ENOMEM;
-	dentry = d_alloc(pipe_mnt->mnt_sb->s_root, &name);
-	if (!dentry)
+	path.dentry = d_alloc(pipe_mnt->mnt_sb->s_root, &name);
+	if (!path.dentry)
 		goto err_inode;
+	path.mnt = mntget(pipe_mnt);
 
-	dentry->d_op = &pipefs_dentry_operations;
+	path.dentry->d_op = &pipefs_dentry_operations;
 	/*
 	 * We dont want to publish this dentry into global dentry hash table.
 	 * We pretend dentry is already hashed, by unsetting DCACHE_UNHASHED
 	 * This permits a working /proc/$pid/fd/XXX on pipes
 	 */
-	dentry->d_flags &= ~DCACHE_UNHASHED;
-	d_instantiate(dentry, inode);
+	path.dentry->d_flags &= ~DCACHE_UNHASHED;
+	d_instantiate(path.dentry, inode);
 
 	err = -ENFILE;
-	f = alloc_file(pipe_mnt, dentry, FMODE_WRITE, &write_pipefifo_fops);
+	f = alloc_file(&path, FMODE_WRITE, &write_pipefifo_fops);
 	if (!f)
 		goto err_dentry;
 	f->f_mapping = inode->i_mapping;
@@ -1009,7 +1010,7 @@ struct file *create_write_pipe(int flags)
 
  err_dentry:
 	free_pipe_info(inode);
-	dput(dentry);
+	path_put(&path);
 	return ERR_PTR(err);
 
  err_inode:
diff --git a/include/linux/file.h b/include/linux/file.h
index 6a8d3612eb2..5555508fd51 100644
--- a/include/linux/file.h
+++ b/include/linux/file.h
@@ -18,8 +18,9 @@ extern void drop_file_write_access(struct file *file);
 struct file_operations;
 struct vfsmount;
 struct dentry;
-extern struct file *alloc_file(struct vfsmount *, struct dentry *dentry,
-		fmode_t mode, const struct file_operations *fop);
+struct path;
+extern struct file *alloc_file(struct path *, fmode_t mode,
+	const struct file_operations *fop);
 
 static inline void fput_light(struct file *file, int fput_needed)
 {
diff --git a/ipc/shm.c b/ipc/shm.c
index 11bec626c22..16e39230aa0 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -878,8 +878,8 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr)
 	if (err)
 		goto out_unlock;
 
-	path.dentry = dget(shp->shm_file->f_path.dentry);
-	path.mnt    = shp->shm_file->f_path.mnt;
+	path = shp->shm_file->f_path;
+	path_get(&path);
 	shp->shm_nattch++;
 	size = i_size_read(path.dentry->d_inode);
 	shm_unlock(shp);
@@ -889,8 +889,8 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr)
 	if (!sfd)
 		goto out_put_dentry;
 
-	file = alloc_file(path.mnt, path.dentry, f_mode,
-			is_file_hugepages(shp->shm_file) ?
+	file = alloc_file(&path, f_mode,
+			  is_file_hugepages(shp->shm_file) ?
 				&shm_file_operations_huge :
 				&shm_file_operations);
 	if (!file)
@@ -950,7 +950,7 @@ out_unlock:
 out_free:
 	kfree(sfd);
 out_put_dentry:
-	dput(path.dentry);
+	path_put(&path);
 	goto out_nattch;
 }
 
diff --git a/mm/shmem.c b/mm/shmem.c
index ef8f47473c5..d2ec7f029ff 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -2626,7 +2626,8 @@ struct file *shmem_file_setup(const char *name, loff_t size, unsigned long flags
 	int error;
 	struct file *file;
 	struct inode *inode;
-	struct dentry *dentry, *root;
+	struct path path;
+	struct dentry *root;
 	struct qstr this;
 
 	if (IS_ERR(shm_mnt))
@@ -2643,16 +2644,17 @@ struct file *shmem_file_setup(const char *name, loff_t size, unsigned long flags
 	this.len = strlen(name);
 	this.hash = 0; /* will go */
 	root = shm_mnt->mnt_root;
-	dentry = d_alloc(root, &this);
-	if (!dentry)
+	path.dentry = d_alloc(root, &this);
+	if (!path.dentry)
 		goto put_memory;
+	path.mnt = mntget(shm_mnt);
 
 	error = -ENOSPC;
 	inode = shmem_get_inode(root->d_sb, S_IFREG | S_IRWXUGO, 0, flags);
 	if (!inode)
 		goto put_dentry;
 
-	d_instantiate(dentry, inode);
+	d_instantiate(path.dentry, inode);
 	inode->i_size = size;
 	inode->i_nlink = 0;	/* It is unlinked */
 #ifndef CONFIG_MMU
@@ -2662,7 +2664,7 @@ struct file *shmem_file_setup(const char *name, loff_t size, unsigned long flags
 #endif
 
 	error = -ENFILE;
-	file = alloc_file(shm_mnt, dentry, FMODE_WRITE | FMODE_READ,
+	file = alloc_file(&path, FMODE_WRITE | FMODE_READ,
 		  &shmem_file_operations);
 	if (!file)
 		goto put_dentry;
@@ -2671,7 +2673,7 @@ struct file *shmem_file_setup(const char *name, loff_t size, unsigned long flags
 	return file;
 
 put_dentry:
-	dput(dentry);
+	path_put(&path);
 put_memory:
 	shmem_unacct_size(flags, size);
 	return ERR_PTR(error);
diff --git a/net/socket.c b/net/socket.c
index eaaba3510e8..dbfdfa96d29 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -358,7 +358,7 @@ static const struct dentry_operations sockfs_dentry_operations = {
 static int sock_alloc_file(struct socket *sock, struct file **f, int flags)
 {
 	struct qstr name = { .name = "" };
-	struct dentry *dentry;
+	struct path path;
 	struct file *file;
 	int fd;
 
@@ -366,28 +366,29 @@ static int sock_alloc_file(struct socket *sock, struct file **f, int flags)
 	if (unlikely(fd < 0))
 		return fd;
 
-	dentry = d_alloc(sock_mnt->mnt_sb->s_root, &name);
-	if (unlikely(!dentry)) {
+	path.dentry = d_alloc(sock_mnt->mnt_sb->s_root, &name);
+	if (unlikely(!path.dentry)) {
 		put_unused_fd(fd);
 		return -ENOMEM;
 	}
+	path.mnt = mntget(sock_mnt);
 
-	dentry->d_op = &sockfs_dentry_operations;
+	path.dentry->d_op = &sockfs_dentry_operations;
 	/*
 	 * We dont want to push this dentry into global dentry hash table.
 	 * We pretend dentry is already hashed, by unsetting DCACHE_UNHASHED
 	 * This permits a working /proc/$pid/fd/XXX on sockets
 	 */
-	dentry->d_flags &= ~DCACHE_UNHASHED;
-	d_instantiate(dentry, SOCK_INODE(sock));
+	path.dentry->d_flags &= ~DCACHE_UNHASHED;
+	d_instantiate(path.dentry, SOCK_INODE(sock));
 	SOCK_INODE(sock)->i_fop = &socket_file_ops;
 
-	file = alloc_file(sock_mnt, dentry, FMODE_READ | FMODE_WRITE,
+	file = alloc_file(&path, FMODE_READ | FMODE_WRITE,
 		  &socket_file_ops);
 	if (unlikely(!file)) {
 		/* drop dentry, keep inode */
 		atomic_inc(&path.dentry->d_inode->i_count);
-		dput(dentry);
+		path_put(&path);
 		put_unused_fd(fd);
 		return -ENFILE;
 	}