Btrfs: Reinstate '-osubvol=.' option to mount entire tree

Date: Tue, 19 Aug 2008 16:49:35 +0100
This disappeared when I removed the special case for '.' in btrfs_lookup()
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

fs/btrfs/super.c

@@ -451,6 +451,9 @@ static int btrfs_get_sb(struct file_system_type *fs_type, int flags,
 		s->s_flags |= MS_ACTIVE;
 	}
 
+	if (!strcmp(subvol_name, "."))
+		root = dget(s->s_root);
+	else {
 		mutex_lock(&s->s_root->d_inode->i_mutex);
 		root = lookup_one_len(subvol_name, s->s_root, strlen(subvol_name));
 		mutex_unlock(&s->s_root->d_inode->i_mutex);
@@ -467,6 +470,7 @@ static int btrfs_get_sb(struct file_system_type *fs_type, int flags,
 			error = -ENXIO;
 			goto error;
 		}
+	}
 
 	mnt->mnt_sb = s;
 	mnt->mnt_root = root;