Merge branch 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs

Pull btrfs fixes from Chris Mason:
 "Josef fixed a problem when quotas are enabled with his latest ENOSPC
  rework, and Jeff added more checks into the subvol ioctls to avoid
  tripping up lookup_one_len"

* 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  btrfs: ensure that file descriptor used with subvol ioctls is a dir
  Btrfs: handle quota reserve failure properly

fs/btrfs/extent-tree.c

@@ -4271,13 +4271,10 @@ int btrfs_check_data_free_space(struct inode *inode, u64 start, u64 len)
 	if (ret < 0)
 		return ret;
 
-	/*
-	 * Use new btrfs_qgroup_reserve_data to reserve precious data space
-	 *
-	 * TODO: Find a good method to avoid reserve data space for NOCOW
-	 * range, but don't impact performance on quota disable case.
-	 */
+	/* Use new btrfs_qgroup_reserve_data to reserve precious data space. */
 	ret = btrfs_qgroup_reserve_data(inode, start, len);
+	if (ret)
+		btrfs_free_reserved_data_space_noquota(inode, start, len);
 	return ret;
 }
 

fs/btrfs/ioctl.c

@@ -1634,6 +1634,9 @@ static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
 	int namelen;
 	int ret = 0;
 
+	if (!S_ISDIR(file_inode(file)->i_mode))
+		return -ENOTDIR;
+
 	ret = mnt_want_write_file(file);
 	if (ret)
 		goto out;
@@ -1691,6 +1694,9 @@ static noinline int btrfs_ioctl_snap_create(struct file *file,
 	struct btrfs_ioctl_vol_args *vol_args;
 	int ret;
 
+	if (!S_ISDIR(file_inode(file)->i_mode))
+		return -ENOTDIR;
+
 	vol_args = memdup_user(arg, sizeof(*vol_args));
 	if (IS_ERR(vol_args))
 		return PTR_ERR(vol_args);
@@ -1714,6 +1720,9 @@ static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
 	bool readonly = false;
 	struct btrfs_qgroup_inherit *inherit = NULL;
 
+	if (!S_ISDIR(file_inode(file)->i_mode))
+		return -ENOTDIR;
+
 	vol_args = memdup_user(arg, sizeof(*vol_args));
 	if (IS_ERR(vol_args))
 		return PTR_ERR(vol_args);
@@ -2357,6 +2366,9 @@ static noinline int btrfs_ioctl_snap_destroy(struct file *file,
 	int ret;
 	int err = 0;
 
+	if (!S_ISDIR(dir->i_mode))
+		return -ENOTDIR;
+
 	vol_args = memdup_user(arg, sizeof(*vol_args));
 	if (IS_ERR(vol_args))
 		return PTR_ERR(vol_args);