Btrfs: don't miss inode ref items in BTRFS_IOC_INO_LOOKUP

If the inode ref key was not found and the current leaf slot
was 0 (first item in the leaf) the code would always return
-ENOENT. This was not correct because the desired inode ref
item might be the last item in the previous leaf.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

1 files changed, 10 insertions, 8 deletions

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index f88eeea365f3..82fb11a361c4 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -2013,19 +2013,21 @@ static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
                 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
                 if (ret < 0)
                         goto out;
+                else if (ret > 0) {
+                        ret = btrfs_previous_item(root, path, dirid,
+                                                  BTRFS_INODE_REF_KEY);
+                        if (ret < 0)
+                                goto out;
+                        else if (ret > 0) {
+                                ret = -ENOENT;
+                                goto out;
+                        }
+                }
 
                 l = path->nodes[0];
                 slot = path->slots[0];
-                if (ret > 0 && slot > 0)
-                        slot--;
                 btrfs_item_key_to_cpu(l, &key, slot);
 
-                if (ret > 0 && (key.objectid != dirid ||
-                                key.type != BTRFS_INODE_REF_KEY)) {
-                        ret = -ENOENT;
-                        goto out;
-                }
-
                 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
                 len = btrfs_inode_ref_name_len(l, iref);
                 ptr -= len + 1;