btrfs: return EPERM upon rmdir on a subvolume

A subvolume cannot be deleted via rmdir, but the error code ENOTEMPTY
is confusing. Return EPERM instead, as this is not permitted.

Signed-off-by: David Sterba <dsterba@suse.cz>

1 files changed, 3 insertions, 2 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index d41e467b4aa2..1c50f7c4f5ac 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -3200,9 +3200,10 @@ static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
         struct btrfs_trans_handle *trans;
         unsigned long nr = 0;
 
-        if (inode->i_size > BTRFS_EMPTY_DIR_SIZE ||
-            btrfs_ino(inode) == BTRFS_FIRST_FREE_OBJECTID)
+        if (inode->i_size > BTRFS_EMPTY_DIR_SIZE)
                 return -ENOTEMPTY;
+        if (btrfs_ino(inode) == BTRFS_FIRST_FREE_OBJECTID)
+                return -EPERM;
 
         trans = __unlink_start_trans(dir, dentry);
         if (IS_ERR(trans))