+ if (ret) {
+ /* btrfs_search_slot() returns the slot where we'd want to
+ insert a backref for parent inode #0xFFFFFFFFFFFFFFFF.
+ The _real_ backref, telling us what the parent inode
+ _actually_ is, will be in the slot _before_ the one
+ that btrfs_search_slot() returns. */
+ if (!slot) {
+ /* Unless there is _no_ key in the tree before... */
+ btrfs_free_path(path);
+ return ERR_PTR(-EIO);
+ }
+ slot--;