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: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 19 insertions, 15 deletions

diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 55f4d00fda3a..f7b3eac7ac6d 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -451,21 +451,25 @@ static int btrfs_get_sb(struct file_system_type *fs_type, int flags,
                 s->s_flags |= MS_ACTIVE;
         }
 
-        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);
-        if (IS_ERR(root)) {
-                up_write(&s->s_umount);
-                deactivate_super(s);
-                error = PTR_ERR(root);
-                goto error;
-        }
-        if (!root->d_inode) {
-                dput(root);
-                up_write(&s->s_umount);
-                deactivate_super(s);
-                error = -ENXIO;
-                goto error;
+        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);
+                if (IS_ERR(root)) {
+                        up_write(&s->s_umount);
+                        deactivate_super(s);
+                        error = PTR_ERR(root);
+                        goto error;
+                }
+                if (!root->d_inode) {
+                        dput(root);
+                        up_write(&s->s_umount);
+                        deactivate_super(s);
+                        error = -ENXIO;
+                        goto error;
+                }
         }
 
         mnt->mnt_sb = s;