vtnet_gtoh16
hdr->hdr_len = vtnet_gtoh16(sc, offset + (tcp->th_off << 2));
hdr->gso_size = vtnet_gtoh16(sc, m->m_pkthdr.tso_segsz);
hdr->csum_start = vtnet_gtoh16(sc, csum_start);
hdr->csum_offset = vtnet_gtoh16(sc, m->m_pkthdr.csum_data);
s.mq.virtqueue_pairs = vtnet_gtoh16(sc, npairs);
s.tag = vtnet_gtoh16(sc, tag);