__btrfs_unlink_inode
ret = __btrfs_unlink_inode(trans, dir, inode, name, NULL);
ret = __btrfs_unlink_inode(trans, BTRFS_I(old_dir),
ret = __btrfs_unlink_inode(trans, BTRFS_I(new_dir),
ret = __btrfs_unlink_inode(trans, BTRFS_I(old_dir),