ntb_peer_msg_write
ntb_peer_msg_write(perf->ntb, peer->pidx, PERF_MSG_LDATA,
ntb_peer_msg_write(perf->ntb, peer->pidx, PERF_MSG_HDATA,
ntb_peer_msg_write(perf->ntb, peer->pidx, PERF_MSG_CMD, cmd);
ntb_peer_msg_write(pp->ntb, pp->out_pidx, 0, count);
ret = ntb_peer_msg_write(msg->tc->ntb, msg->pidx, msg->midx, val);