nvmf_che_construct_pdu
m = nvmf_che_construct_pdu(qp, &r2t, sizeof(r2t), NULL, 0);
top = nvmf_che_construct_pdu(qp, &h2c, sizeof(h2c), m, len);
top = nvmf_che_construct_pdu(qp, &cmd, sizeof(cmd), m, m != NULL ?
return (nvmf_che_construct_pdu(qp, &rsp, sizeof(rsp), NULL, 0));
top = nvmf_che_construct_pdu(qp, &c2h, sizeof(c2h), m, len);