qtree_get_next_id
status = qtree_get_next_id(&info->dqi_gi, qid);
EXPORT_SYMBOL(qtree_get_next_id);
ret = qtree_get_next_id(sb_dqinfo(sb, qid->type)->dqi_priv, qid);
int qtree_get_next_id(struct qtree_mem_dqinfo *info, struct kqid *qid);