NVME_IOQ_DEFAULT
ioq = req->ioq == NVME_IOQ_DEFAULT ? QP(ctrlr, curcpu) : req->ioq;
req->ioq = NVME_IOQ_DEFAULT;
KASSERT(ioq == NVME_IOQ_DEFAULT || ioq < ctrlr->num_io_queues,
ioq = NVME_IOQ_DEFAULT;