static uint16_t nvme_map_prp(QEMUSGList *qsg, QEMUIOVector *iov, uint64_t prp1, uint64_t prp2, uint32_t len, NvmeCtrl *n) { hwaddr trans_len = n->page_size - (prp1 % n->page_size); trans_len = MIN(len, trans_len); int num_prps = (len >> n->page_bits) + 1; if (!prp1) { return NVME_INVALID_FIELD | NVME_DNR; } else if (n->cmbsz && prp1 >= n->ctrl_mem.addr && prp1 < n->ctrl_mem.addr + int128_get64(n->ctrl_mem.size)) { qsg->nsg = 0; qemu_iovec_init(iov, num_prps); qemu_iovec_add(iov, (void *)&n->cmbuf[prp1 - n->ctrl_mem.addr], trans_len); } else { pci_dma_sglist_init(qsg, &n->parent_obj, num_prps); qemu_sglist_add(qsg, prp1, trans_len); } len -= trans_len; if (len) { if (!prp2) { goto unmap; } if (len > n->page_size) { uint64_t prp_list[n->max_prp_ents]; uint32_t nents, prp_trans; int i = 0; nents = (len + n->page_size - 1) >> n->page_bits; prp_trans = MIN(n->max_prp_ents, nents) * sizeof(uint64_t); nvme_addr_read(n, prp2, (void *)prp_list, prp_trans); while (len != 0) { uint64_t prp_ent = le64_to_cpu(prp_list[i]); if (i == n->max_prp_ents - 1 && len > n->page_size) { if (!prp_ent || prp_ent & (n->page_size - 1)) { goto unmap; } i = 0; nents = (len + n->page_size - 1) >> n->page_bits; prp_trans = MIN(n->max_prp_ents, nents) * sizeof(uint64_t); nvme_addr_read(n, prp_ent, (void *)prp_list, prp_trans); prp_ent = le64_to_cpu(prp_list[i]); } if (!prp_ent || prp_ent & (n->page_size - 1)) { goto unmap; } trans_len = MIN(len, n->page_size); if (qsg->nsg){ qemu_sglist_add(qsg, prp_ent, trans_len); } else { qemu_iovec_add(iov, (void *)&n->cmbuf[prp_ent - n->ctrl_mem.addr], trans_len); } len -= trans_len; i++; } } else { if (prp2 & (n->page_size - 1)) { goto unmap; } if (qsg->nsg) { qemu_sglist_add(qsg, prp2, len); } else { qemu_iovec_add(iov, (void *)&n->cmbuf[prp2 - n->ctrl_mem.addr], trans_len); } } } return NVME_SUCCESS; unmap: qemu_sglist_destroy(qsg); return NVME_INVALID_FIELD | NVME_DNR; }