btrfs_del_inode_ref
int btrfs_del_inode_ref(struct btrfs_trans_handle *trans,
ret = btrfs_del_inode_ref(trans, root, name, ino, dir_ino, &index);
ret2 = btrfs_del_inode_ref(trans, root, name, ino, parent_ino, NULL);
ret = btrfs_del_inode_ref(trans, root->log_root, name, btrfs_ino(inode),