sg_to_qm_sg_last
sg_to_qm_sg_last(req->src, src_len, sg_table + qm_sg_index, 0);
sg_to_qm_sg_last(req->dst, dst_len, sg_table + qm_sg_index, 0);
sg_to_qm_sg_last(req->src, src_len,
sg_to_qm_sg_last(req->src, req->nbytes, sg_table + qm_sg_src_index, 0);
sg_to_qm_sg_last(req->src, req->nbytes, sg_table, 0);
sg_to_qm_sg_last(req->src, src_len, sg_table + 1, 0);
sg_to_qm_sg_last(req->src, req->nbytes, sg_table + 1, 0);
sg_to_qm_sg_last(req->src, src_len, sg_table, 0);
sg_to_qm_sg_last(req->src, src_len, sg_table + qm_sg_index, 0);
sg_to_qm_sg_last(req->dst, dst_len, sg_table + qm_sg_index, 0);