block: add NVMe boot support
This patch enables SeaBIOS to boot from NVMe. Finding namespaces and
basic I/O works. Testing has been done in qemu and so far it works with
Grub, syslinux, and the FreeBSD loader. You need a recent Qemu (>=
2.7.0), because older versions have buggy NVMe support.
The NVMe code is currently only enabled on Qemu due to lack of testing
on real hardware.
Signed-off-by: Julian Stecklina <jsteckli@amazon.de>
diff --git a/src/hw/nvme-int.h b/src/hw/nvme-int.h
new file mode 100644
index 0000000..9f95dd8
--- /dev/null
+++ b/src/hw/nvme-int.h
@@ -0,0 +1,199 @@
+// NVMe datastructures and constants
+//
+// Copyright 2017 Amazon.com, Inc. or its affiliates.
+//
+// This file may be distributed under the terms of the GNU LGPLv3 license.
+
+#ifndef __NVME_INT_H
+#define __NVME_INT_H
+
+#include "types.h" // u32
+#include "pcidevice.h" // struct pci_device
+
+/* Data structures */
+
+/* The register file of a NVMe host controller. This struct follows the naming
+ scheme in the NVMe specification. */
+struct nvme_reg {
+ u64 cap; /* controller capabilities */
+ u32 vs; /* version */
+ u32 intms; /* interrupt mask set */
+ u32 intmc; /* interrupt mask clear */
+ u32 cc; /* controller configuration */
+ u32 _res0;
+ u32 csts; /* controller status */
+ u32 _res1;
+ u32 aqa; /* admin queue attributes */
+ u64 asq; /* admin submission queue base address */
+ u64 acq; /* admin completion queue base address */
+};
+
+/* Submission queue entry */
+struct nvme_sqe {
+ union {
+ u32 dword[16];
+ struct {
+ u32 cdw0; /* Command DWORD 0 */
+ u32 nsid; /* Namespace ID */
+ u64 _res0;
+ u64 mptr; /* metadata ptr */
+
+ u64 dptr_prp1;
+ u64 dptr_prp2;
+ };
+ };
+};
+
+/* Completion queue entry */
+struct nvme_cqe {
+ union {
+ u32 dword[4];
+ struct {
+ u32 cdw0;
+ u32 _res0;
+ u16 sq_head;
+ u16 sq_id;
+ u16 cid;
+ u16 status;
+ };
+ };
+};
+
+/* The common part of every submission or completion queue. */
+struct nvme_queue {
+ u32 *dbl; /* doorbell */
+ u16 mask; /* length - 1 */
+};
+
+struct nvme_cq {
+ struct nvme_queue common;
+ struct nvme_cqe *cqe;
+
+ /* We have read upto (but not including) this entry in the queue. */
+ u16 head;
+
+ /* The current phase bit the controller uses to indicate that it has written
+ a new entry. This is inverted after each wrap. */
+ unsigned phase : 1;
+};
+
+struct nvme_sq {
+ struct nvme_queue common;
+ struct nvme_sqe *sqe;
+
+ /* Corresponding completion queue. We only support a single SQ per CQ. */
+ struct nvme_cq *cq;
+
+ /* The last entry the controller has fetched. */
+ u16 head;
+
+ /* The last value we have written to the tail doorbell. */
+ u16 tail;
+};
+
+struct nvme_ctrl {
+ struct pci_device *pci;
+ struct nvme_reg volatile *reg;
+
+ u32 doorbell_stride; /* in bytes */
+
+ struct nvme_sq admin_sq;
+ struct nvme_cq admin_cq;
+
+ u32 ns_count;
+ struct nvme_namespace *ns;
+
+ struct nvme_sq io_sq;
+ struct nvme_cq io_cq;
+};
+
+struct nvme_namespace {
+ struct drive_s drive;
+ struct nvme_ctrl *ctrl;
+
+ u32 ns_id;
+
+ u64 lba_count; /* The total amount of sectors. */
+
+ u32 block_size;
+ u32 metadata_size;
+
+ /* Page aligned buffer of size NVME_PAGE_SIZE. */
+ char *dma_buffer;
+};
+
+/* Data structures for NVMe admin identify commands */
+
+struct nvme_identify_ctrl {
+ u16 vid;
+ u16 ssvid;
+ char sn[20];
+ char mn[40];
+ char fr[8];
+
+ char _boring[516 - 72];
+
+ u32 nn; /* number of namespaces */
+};
+
+struct nvme_identify_ns_list {
+ u32 ns_id[1024];
+};
+
+struct nvme_lba_format {
+ u16 ms;
+ u8 lbads;
+ u8 rp;
+ u8 res;
+};
+
+struct nvme_identify_ns {
+ u64 nsze;
+ u64 ncap;
+ u64 nuse;
+ u8 nsfeat;
+ u8 nlbaf;
+ u8 flbas;
+
+ char _boring[128 - 27];
+
+ struct nvme_lba_format lbaf[16];
+};
+
+union nvme_identify {
+ struct nvme_identify_ns ns;
+ struct nvme_identify_ctrl ctrl;
+ struct nvme_identify_ns_list ns_list;
+};
+
+/* NVMe constants */
+
+#define NVME_CAP_CSS_NVME (1ULL << 37)
+
+#define NVME_CSTS_FATAL (1U << 1)
+#define NVME_CSTS_RDY (1U << 0)
+
+#define NVME_CC_EN (1U << 0)
+
+#define NVME_SQE_OPC_ADMIN_CREATE_IO_SQ 1U
+#define NVME_SQE_OPC_ADMIN_CREATE_IO_CQ 5U
+#define NVME_SQE_OPC_ADMIN_IDENTIFY 6U
+
+#define NVME_SQE_OPC_IO_WRITE 1U
+#define NVME_SQE_OPC_IO_READ 2U
+
+#define NVME_ADMIN_IDENTIFY_CNS_ID_NS 0U
+#define NVME_ADMIN_IDENTIFY_CNS_ID_CTRL 1U
+#define NVME_ADMIN_IDENTIFY_CNS_GET_NS_LIST 2U
+
+#define NVME_CQE_DW3_P (1U << 16)
+
+#define NVME_PAGE_SIZE 4096
+
+/* Length for the queue entries. */
+#define NVME_SQE_SIZE_LOG 6
+#define NVME_CQE_SIZE_LOG 4
+
+#endif
+
+/* EOF */
diff --git a/src/hw/nvme.c b/src/hw/nvme.c
new file mode 100644
index 0000000..31edf29
--- /dev/null
+++ b/src/hw/nvme.c
@@ -0,0 +1,655 @@
+// Low level NVMe disk access
+//
+// Copyright 2017 Amazon.com, Inc. or its affiliates.
+//
+// This file may be distributed under the terms of the GNU LGPLv3 license.
+
+#include "blockcmd.h"
+#include "fw/paravirt.h" // runningOnQEMU
+#include "malloc.h" // malloc_high
+#include "output.h" // dprintf
+#include "pci.h"
+#include "pci_ids.h" // PCI_CLASS_STORAGE_NVME
+#include "pci_regs.h" // PCI_BASE_ADDRESS_0
+#include "pcidevice.h" // foreachpci
+#include "stacks.h" // yield
+#include "std/disk.h" // DISK_RET_
+#include "string.h" // memset
+#include "util.h" // boot_add_hd
+#include "x86.h" // readl
+
+#include "nvme.h"
+#include "nvme-int.h"
+
+static void *
+zalloc_page_aligned(struct zone_s *zone, u32 size)
+{
+ void *res = _malloc(zone, size, NVME_PAGE_SIZE);
+ if (res) memset(res, 0, size);
+ return res;
+}
+
+static void
+nvme_init_queue_common(struct nvme_ctrl *ctrl, struct nvme_queue *q, u16 q_idx,
+ u16 length)
+{
+ memset(q, 0, sizeof(*q));
+ q->dbl = (u32 *)((char *)ctrl->reg + 0x1000 + q_idx * ctrl->doorbell_stride);
+ dprintf(3, " q %p q_idx %u dbl %p\n", q, q_idx, q->dbl);
+ q->mask = length - 1;
+}
+
+static void
+nvme_init_sq(struct nvme_ctrl *ctrl, struct nvme_sq *sq, u16 q_idx, u16 length,
+ struct nvme_cq *cq)
+{
+ nvme_init_queue_common(ctrl, &sq->common, q_idx, length);
+ sq->sqe = zalloc_page_aligned(&ZoneHigh, sizeof(*sq->sqe) * length);
+ dprintf(3, "sq %p q_idx %u sqe %p\n", sq, q_idx, sq->sqe);
+ sq->cq = cq;
+ sq->head = 0;
+ sq->tail = 0;
+}
+
+static void
+nvme_init_cq(struct nvme_ctrl *ctrl, struct nvme_cq *cq, u16 q_idx, u16 length)
+{
+ nvme_init_queue_common(ctrl, &cq->common, q_idx, length);
+ cq->cqe = zalloc_page_aligned(&ZoneHigh, sizeof(*cq->cqe) * length);
+
+ cq->head = 0;
+
+ /* All CQE phase bits are initialized to zero. This means initially we wait
+ for the host controller to set these to 1. */
+ cq->phase = 1;
+}
+
+static int
+nvme_poll_cq(struct nvme_cq *cq)
+{
+ u32 dw3 = readl(&cq->cqe[cq->head].dword[3]);
+ return (!!(dw3 & NVME_CQE_DW3_P) == cq->phase);
+}
+
+static int
+nvme_is_cqe_success(struct nvme_cqe const *cqe)
+{
+ return (cqe->status & 0xFF) >> 1 == 0;
+}
+
+
+static struct nvme_cqe
+nvme_error_cqe(void)
+{
+ struct nvme_cqe r;
+
+ /* 0xFF is a vendor specific status code != success. Should be okay for
+ indicating failure. */
+ memset(&r, 0xFF, sizeof(r));
+ return r;
+}
+
+static struct nvme_cqe
+nvme_consume_cqe(struct nvme_sq *sq)
+{
+ struct nvme_cq *cq = sq->cq;
+
+ if (!nvme_poll_cq(cq)) {
+ /* Cannot consume a completion queue entry, if there is none ready. */
+ return nvme_error_cqe();
+ }
+
+ struct nvme_cqe *cqe = &cq->cqe[cq->head];
+ u16 cq_next_head = (cq->head + 1) & cq->common.mask;
+ dprintf(4, "cq %p head %u -> %u\n", cq, cq->head, cq_next_head);
+ if (cq_next_head < cq->head) {
+ dprintf(3, "cq %p wrap\n", cq);
+ cq->phase = ~cq->phase;
+ }
+ cq->head = cq_next_head;
+
+ /* Update the submission queue head. */
+ if (cqe->sq_head != sq->head) {
+ sq->head = cqe->sq_head;
+ dprintf(4, "sq %p advanced to %u\n", sq, cqe->sq_head);
+ }
+
+ /* Tell the controller that we consumed the completion. */
+ writel(cq->common.dbl, cq->head);
+
+ return *cqe;
+}
+
+static struct nvme_cqe
+nvme_wait(struct nvme_sq *sq)
+{
+ static const unsigned nvme_timeout = 500 /* ms */;
+ u32 to = timer_calc(nvme_timeout);
+ while (!nvme_poll_cq(sq->cq)) {
+ yield();
+
+ if (timer_check(to)) {
+ warn_timeout();
+ return nvme_error_cqe();
+ }
+ }
+
+ return nvme_consume_cqe(sq);
+}
+
+/* Returns the next submission queue entry (or NULL if the queue is full). It
+ also fills out Command Dword 0 and clears the rest. */
+static struct nvme_sqe *
+nvme_get_next_sqe(struct nvme_sq *sq, u8 opc, void *metadata, void *data)
+{
+ if (((sq->head + 1) & sq->common.mask) == sq->tail) {
+ dprintf(3, "submission queue is full");
+ return NULL;
+ }
+
+ struct nvme_sqe *sqe = &sq->sqe[sq->tail];
+ dprintf(4, "sq %p next_sqe %u\n", sq, sq->tail);
+
+ memset(sqe, 0, sizeof(*sqe));
+ sqe->cdw0 = opc | (sq->tail << 16 /* CID */);
+ sqe->mptr = (u32)metadata;
+ sqe->dptr_prp1 = (u32)data;
+
+ if (sqe->dptr_prp1 & (NVME_PAGE_SIZE - 1)) {
+ /* Data buffer not page aligned. */
+ warn_internalerror();
+ }
+
+ return sqe;
+}
+
+/* Call this after you've filled out an sqe that you've got from nvme_get_next_sqe. */
+static void
+nvme_commit_sqe(struct nvme_sq *sq)
+{
+ dprintf(4, "sq %p commit_sqe %u\n", sq, sq->tail);
+ sq->tail = (sq->tail + 1) & sq->common.mask;
+ writel(sq->common.dbl, sq->tail);
+}
+
+/* Perform an identify command on the admin queue and return the resulting
+ buffer. This may be a NULL pointer, if something failed. This function
+ cannot be used after initialization, because it uses buffers in tmp zone. */
+static union nvme_identify *
+nvme_admin_identify(struct nvme_ctrl *ctrl, u8 cns, u32 nsid)
+{
+ union nvme_identify *identify_buf = zalloc_page_aligned(&ZoneTmpHigh, 4096);
+ if (!identify_buf) {
+ /* Could not allocate identify buffer. */
+ warn_internalerror();
+ return NULL;
+ }
+
+ struct nvme_sqe *cmd_identify;
+ cmd_identify = nvme_get_next_sqe(&ctrl->admin_sq,
+ NVME_SQE_OPC_ADMIN_IDENTIFY, NULL,
+ identify_buf);
+
+ if (!cmd_identify) {
+ warn_internalerror();
+ goto error;
+ }
+
+ cmd_identify->nsid = nsid;
+ cmd_identify->dword[10] = cns;
+
+ nvme_commit_sqe(&ctrl->admin_sq);
+
+ struct nvme_cqe cqe = nvme_wait(&ctrl->admin_sq);
+
+ if (!nvme_is_cqe_success(&cqe)) {
+ goto error;
+ }
+
+ return identify_buf;
+ error:
+ free(identify_buf);
+ return NULL;
+}
+
+static struct nvme_identify_ctrl *
+nvme_admin_identify_ctrl(struct nvme_ctrl *ctrl)
+{
+ return &nvme_admin_identify(ctrl, NVME_ADMIN_IDENTIFY_CNS_ID_CTRL, 0)->ctrl;
+}
+
+static struct nvme_identify_ns_list *
+nvme_admin_identify_get_ns_list(struct nvme_ctrl *ctrl)
+{
+ return &nvme_admin_identify(ctrl, NVME_ADMIN_IDENTIFY_CNS_GET_NS_LIST,
+ 0)->ns_list;
+}
+
+static struct nvme_identify_ns *
+nvme_admin_identify_ns(struct nvme_ctrl *ctrl, u32 ns_id)
+{
+ return &nvme_admin_identify(ctrl, NVME_ADMIN_IDENTIFY_CNS_ID_NS,
+ ns_id)->ns;
+}
+
+static void
+nvme_probe_ns(struct nvme_ctrl *ctrl, struct nvme_namespace *ns, u32 ns_id)
+{
+ ns->ctrl = ctrl;
+ ns->ns_id = ns_id;
+
+ struct nvme_identify_ns *id = nvme_admin_identify_ns(ctrl, ns_id);
+ if (!id) {
+ dprintf(2, "NVMe couldn't identify namespace %u.\n", ns_id);
+ goto free_buffer;
+ }
+
+ u8 current_lba_format = id->flbas & 0xF;
+ if (current_lba_format > id->nlbaf) {
+ dprintf(2, "NVMe NS %u: current LBA format %u is beyond what the "
+ " namespace supports (%u)?\n",
+ ns_id, current_lba_format, id->nlbaf + 1);
+ goto free_buffer;
+ }
+
+ ns->lba_count = id->nsze;
+
+ struct nvme_lba_format *fmt = &id->lbaf[current_lba_format];
+
+ ns->block_size = 1U << fmt->lbads;
+ ns->metadata_size = fmt->ms;
+
+ if (ns->block_size > NVME_PAGE_SIZE) {
+ /* If we see devices that trigger this path, we need to increase our
+ buffer size. */
+ warn_internalerror();
+ goto free_buffer;
+ }
+
+ ns->drive.cntl_id = ns - ctrl->ns;
+ ns->drive.removable = 0;
+ ns->drive.type = DTYPE_NVME;
+ ns->drive.blksize = ns->block_size;
+ ns->drive.sectors = ns->lba_count;
+
+ ns->dma_buffer = zalloc_page_aligned(&ZoneHigh, NVME_PAGE_SIZE);
+
+ char *desc = znprintf(MAXDESCSIZE, "NVMe NS %u: %llu MiB (%llu %u-byte "
+ "blocks + %u-byte metadata)\n",
+ ns_id, (ns->lba_count * ns->block_size) >> 20,
+ ns->lba_count, ns->block_size, ns->metadata_size);
+
+ dprintf(3, "%s", desc);
+ boot_add_hd(&ns->drive, desc, bootprio_find_pci_device(ctrl->pci));
+
+ free_buffer:
+ free (id);
+ }
+
+/* Returns 0 on success. */
+static int
+nvme_create_io_cq(struct nvme_ctrl *ctrl, struct nvme_cq *cq, u16 q_idx)
+{
+ struct nvme_sqe *cmd_create_cq;
+
+ nvme_init_cq(ctrl, cq, q_idx, NVME_PAGE_SIZE / sizeof(struct nvme_cqe));
+ cmd_create_cq = nvme_get_next_sqe(&ctrl->admin_sq,
+ NVME_SQE_OPC_ADMIN_CREATE_IO_CQ, NULL,
+ cq->cqe);
+ if (!cmd_create_cq) {
+ return -1;
+ }
+
+ cmd_create_cq->dword[10] = (cq->common.mask << 16) | (q_idx >> 1);
+ cmd_create_cq->dword[11] = 1 /* physically contiguous */;
+
+ nvme_commit_sqe(&ctrl->admin_sq);
+
+ struct nvme_cqe cqe = nvme_wait(&ctrl->admin_sq);
+
+ if (!nvme_is_cqe_success(&cqe)) {
+ dprintf(2, "create io cq failed: %08x %08x %08x %08x\n",
+ cqe.dword[0], cqe.dword[1], cqe.dword[2], cqe.dword[3]);
+
+ return -1;
+ }
+
+ return 0;
+}
+
+/* Returns 0 on success. */
+static int
+nvme_create_io_sq(struct nvme_ctrl *ctrl, struct nvme_sq *sq, u16 q_idx, struct nvme_cq *cq)
+{
+ struct nvme_sqe *cmd_create_sq;
+
+ nvme_init_sq(ctrl, sq, q_idx, NVME_PAGE_SIZE / sizeof(struct nvme_cqe), cq);
+ cmd_create_sq = nvme_get_next_sqe(&ctrl->admin_sq,
+ NVME_SQE_OPC_ADMIN_CREATE_IO_SQ, NULL,
+ sq->sqe);
+ if (!cmd_create_sq) {
+ return -1;
+ }
+
+ cmd_create_sq->dword[10] = (sq->common.mask << 16) | (q_idx >> 1);
+ cmd_create_sq->dword[11] = (q_idx >> 1) << 16 | 1 /* contiguous */;
+ dprintf(3, "sq %p create dword10 %08x dword11 %08x\n", sq,
+ cmd_create_sq->dword[10], cmd_create_sq->dword[11]);
+
+ nvme_commit_sqe(&ctrl->admin_sq);
+
+ struct nvme_cqe cqe = nvme_wait(&ctrl->admin_sq);
+
+ if (!nvme_is_cqe_success(&cqe)) {
+ dprintf(2, "create io sq failed: %08x %08x %08x %08x\n",
+ cqe.dword[0], cqe.dword[1], cqe.dword[2], cqe.dword[3]);
+ return -1;
+ }
+
+ return 0;
+}
+
+/* Reads count sectors into buf. Returns DISK_RET_*. The buffer cannot cross
+ page boundaries. */
+static int
+nvme_io_readwrite(struct nvme_namespace *ns, u64 lba, char *buf, u16 count,
+ int write)
+{
+ u32 buf_addr = (u32)buf;
+
+ if ((buf_addr & 0x3) ||
+ ((buf_addr & ~(NVME_PAGE_SIZE - 1)) !=
+ ((buf_addr + ns->block_size * count - 1) & ~(NVME_PAGE_SIZE - 1)))) {
+ /* Buffer is misaligned or crosses page boundary */
+ warn_internalerror();
+ return DISK_RET_EBADTRACK;
+ }
+
+ struct nvme_sqe *io_read = nvme_get_next_sqe(&ns->ctrl->io_sq,
+ write ? NVME_SQE_OPC_IO_WRITE
+ : NVME_SQE_OPC_IO_READ,
+ NULL, buf);
+ io_read->nsid = ns->ns_id;
+ io_read->dword[10] = (u32)lba;
+ io_read->dword[11] = (u32)(lba >> 32);
+ io_read->dword[12] = (1U << 31 /* limited retry */) | (count - 1);
+
+ nvme_commit_sqe(&ns->ctrl->io_sq);
+
+ struct nvme_cqe cqe = nvme_wait(&ns->ctrl->io_sq);
+
+ if (!nvme_is_cqe_success(&cqe)) {
+ dprintf(2, "read io: %08x %08x %08x %08x\n",
+ cqe.dword[0], cqe.dword[1], cqe.dword[2], cqe.dword[3]);
+
+ return DISK_RET_EBADTRACK;
+ }
+
+ return DISK_RET_SUCCESS;
+}
+
+
+static int
+nvme_create_io_queues(struct nvme_ctrl *ctrl)
+{
+ if (nvme_create_io_cq(ctrl, &ctrl->io_cq, 3))
+ return -1;
+
+ if (nvme_create_io_sq(ctrl, &ctrl->io_sq, 2, &ctrl->io_cq))
+ return -1;
+
+ return 0;
+}
+
+/* Waits for CSTS.RDY to match rdy. Returns 0 on success. */
+static int
+nvme_wait_csts_rdy(struct nvme_ctrl *ctrl, unsigned rdy)
+{
+ u32 const max_to = 500 /* ms */ * ((ctrl->reg->cap >> 24) & 0xFFU);
+ u32 to = timer_calc(max_to);
+ u32 csts;
+
+ while (rdy != ((csts = ctrl->reg->csts) & NVME_CSTS_RDY)) {
+ yield();
+
+ if (csts & NVME_CSTS_FATAL) {
+ dprintf(3, "NVMe fatal error during controller shutdown\n");
+ return -1;
+ }
+
+ if (timer_check(to)) {
+ warn_timeout();
+ return -1;
+ }
+ }
+
+ return 0;
+}
+
+/* Returns 0 on success. */
+static int
+nvme_controller_enable(struct nvme_ctrl *ctrl)
+{
+ pci_enable_busmaster(ctrl->pci);
+
+ /* Turn the controller off. */
+ ctrl->reg->cc = 0;
+ if (nvme_wait_csts_rdy(ctrl, 0)) {
+ dprintf(2, "NVMe fatal error during controller shutdown\n");
+ return -1;
+ }
+
+ ctrl->doorbell_stride = 4U << ((ctrl->reg->cap >> 32) & 0xF);
+
+ nvme_init_cq(ctrl, &ctrl->admin_cq, 1,
+ NVME_PAGE_SIZE / sizeof(struct nvme_cqe));
+
+ nvme_init_sq(ctrl, &ctrl->admin_sq, 0,
+ NVME_PAGE_SIZE / sizeof(struct nvme_sqe), &ctrl->admin_cq);
+
+ ctrl->reg->aqa = ctrl->admin_cq.common.mask << 16
+ | ctrl->admin_sq.common.mask;
+
+ /* Create the admin queue pair */
+ if (!ctrl->admin_sq.sqe || !ctrl->admin_cq.cqe) goto out_of_memory;
+
+ ctrl->reg->asq = (u32)ctrl->admin_sq.sqe;
+ ctrl->reg->acq = (u32)ctrl->admin_cq.cqe;
+
+ dprintf(3, " admin submission queue: %p\n", ctrl->admin_sq.sqe);
+ dprintf(3, " admin completion queue: %p\n", ctrl->admin_cq.cqe);
+
+ ctrl->reg->cc = NVME_CC_EN | (NVME_CQE_SIZE_LOG << 20)
+ | (NVME_SQE_SIZE_LOG << 16 /* IOSQES */);
+
+ if (nvme_wait_csts_rdy(ctrl, 1)) {
+ dprintf(2, "NVMe fatal error while enabling controller\n");
+ goto failed;
+ }
+ /* The admin queue is set up and the controller is ready. Let's figure out
+ what namespaces we have. */
+
+ struct nvme_identify_ctrl *identify = nvme_admin_identify_ctrl(ctrl);
+
+ if (!identify) {
+ dprintf(2, "NVMe couldn't identify controller.\n");
+ goto failed;
+ }
+
+ /* TODO Print model/serial info. */
+ dprintf(3, "NVMe has %u namespace%s.\n",
+ identify->nn, (identify->nn == 1) ? "" : "s");
+
+ ctrl->ns_count = identify->nn;
+ free(identify);
+
+ if ((ctrl->ns_count == 0) || nvme_create_io_queues(ctrl)) {
+ /* No point to continue, if the controller says it doesn't have
+ namespaces or we couldn't create I/O queues. */
+ goto failed;
+ }
+
+ ctrl->ns = malloc_fseg(sizeof(*ctrl->ns) * ctrl->ns_count);
+ if (!ctrl->ns) goto out_of_memory;
+ memset(ctrl->ns, 0, sizeof(*ctrl->ns) * ctrl->ns_count);
+
+ struct nvme_identify_ns_list *ns_list = nvme_admin_identify_get_ns_list(ctrl);
+ if (!ns_list) {
+ dprintf(2, "NVMe couldn't get namespace list.\n");
+ goto failed;
+ }
+
+ /* Populate namespace IDs */
+ int ns_idx;
+ for (ns_idx = 0;
+ ns_idx < ARRAY_SIZE(ns_list->ns_id)
+ && ns_idx < ctrl->ns_count
+ && ns_list->ns_id[ns_idx];
+ ns_idx++) {
+ nvme_probe_ns(ctrl, &ctrl->ns[ns_idx], ns_list->ns_id[ns_idx]);
+ }
+
+ free(ns_list);
+
+ /* If for some reason the namespace list gives us fewer namespaces, we just
+ go along. */
+ if (ns_idx != ctrl->ns_count) {
+ dprintf(2, "NVMe namespace list has only %u namespaces?\n", ns_idx);
+ ctrl->ns_count = ns_idx;
+ }
+
+ dprintf(3, "NVMe initialization complete!\n");
+ return 0;
+
+ out_of_memory:
+ warn_noalloc();
+ failed:
+ free(ctrl->admin_sq.sqe);
+ free(ctrl->admin_cq.cqe);
+ free(ctrl->ns);
+ return -1;
+}
+
+/* Initialize an NVMe controller and detect its drives. */
+static void
+nvme_controller_setup(void *opaque)
+{
+ struct pci_device *pci = opaque;
+
+ struct nvme_reg volatile *reg = pci_enable_membar(pci, PCI_BASE_ADDRESS_0);
+ if (!reg)
+ return;
+
+ u32 version = reg->vs;
+ dprintf(3, "Found NVMe controller with version %u.%u.%u.\n",
+ version >> 16, (version >> 8) & 0xFF, version & 0xFF);
+ dprintf(3, " Capabilities %016llx\n", reg->cap);
+
+ if (version < 0x00010100U) {
+ dprintf(3, "Need at least 1.1.0! Skipping.\n");
+ return;
+ }
+
+ if (~reg->cap & NVME_CAP_CSS_NVME) {
+ dprintf(3, "Controller doesn't speak NVMe command set. Skipping.\n");
+ return;
+ }
+
+ struct nvme_ctrl *ctrl = malloc_high(sizeof(*ctrl));
+ if (!ctrl) {
+ warn_noalloc();
+ return;
+ }
+
+ memset(ctrl, 0, sizeof(*ctrl));
+
+ ctrl->reg = reg;
+ ctrl->pci = pci;
+
+ if (nvme_controller_enable(ctrl)) {
+ /* Initialization failed */
+ free(ctrl);
+ }
+}
+
+// Locate and init NVMe controllers
+static void
+nvme_scan(void)
+{
+ // Scan PCI bus for ATA adapters
+ struct pci_device *pci;
+
+ foreachpci(pci) {
+ if (pci->class != PCI_CLASS_STORAGE_NVME)
+ continue;
+ if (pci->prog_if != 2 /* as of NVM 1.0e */) {
+ dprintf(3, "Found incompatble NVMe: prog-if=%02x\n", pci->prog_if);
+ continue;
+ }
+
+ run_thread(nvme_controller_setup, pci);
+ }
+}
+
+static int
+nvme_cmd_readwrite(struct nvme_namespace *ns, struct disk_op_s *op, int write)
+{
+ int res = DISK_RET_SUCCESS;
+ u16 const max_blocks = NVME_PAGE_SIZE / ns->block_size;
+ u16 i;
+
+ for (i = 0; i < op->count || res != DISK_RET_SUCCESS;) {
+ u16 blocks_remaining = op->count - i;
+ u16 blocks = blocks_remaining < max_blocks ? blocks_remaining
+ : max_blocks;
+ char *op_buf = op->buf_fl + i * ns->block_size;
+
+ if (write) {
+ memcpy(ns->dma_buffer, op_buf, blocks * ns->block_size);
+ }
+
+ res = nvme_io_readwrite(ns, op->lba + i, ns->dma_buffer, blocks, write);
+ dprintf(3, "ns %u %s lba %llu+%u: %d\n", ns->ns_id, write ? "write"
+ : "read",
+ op->lba + i, blocks, res);
+
+ if (!write && res == DISK_RET_SUCCESS) {
+ memcpy(op_buf, ns->dma_buffer, blocks * ns->block_size);
+ }
+
+ i += blocks;
+ }
+
+ return res;
+}
+
+int
+nvme_process_op(struct disk_op_s *op)
+{
+ if (!CONFIG_NVME || !runningOnQEMU())
+ return DISK_RET_SUCCESS;
+
+ struct nvme_namespace *ns = container_of(op->drive_gf, struct nvme_namespace,
+ drive);
+
+ switch (op->command) {
+ case CMD_READ:
+ case CMD_WRITE:
+ return nvme_cmd_readwrite(ns, op, op->command == CMD_WRITE);
+ default:
+ return default_process_op(op);
+ }
+}
+
+void
+nvme_setup(void)
+{
+ ASSERT32FLAT();
+ if (!CONFIG_NVME || !runningOnQEMU())
+ return;
+
+ dprintf(3, "init nvme\n");
+ nvme_scan();
+}
+
+/* EOF */
diff --git a/src/hw/nvme.h b/src/hw/nvme.h
new file mode 100644
index 0000000..4dbb70a
--- /dev/null
+++ b/src/hw/nvme.h
@@ -0,0 +1,17 @@
+// External interfaces for low level NVMe support
+//
+// Copyright 2017 Amazon.com, Inc. or its affiliates.
+//
+// This file may be distributed under the terms of the GNU LGPLv3 license.
+
+#ifndef __NVME_H
+#define __NVME_H
+
+#include "block.h" // struct disk_op_s
+
+void nvme_setup(void);
+int nvme_process_op(struct disk_op_s *op);
+
+#endif
+
+/* EOF */
diff --git a/src/hw/pci_ids.h b/src/hw/pci_ids.h
index cdf9b3c..4ac73b4 100644
--- a/src/hw/pci_ids.h
+++ b/src/hw/pci_ids.h
@@ -18,6 +18,7 @@
#define PCI_CLASS_STORAGE_SATA 0x0106
#define PCI_CLASS_STORAGE_SATA_AHCI 0x010601
#define PCI_CLASS_STORAGE_SAS 0x0107
+#define PCI_CLASS_STORAGE_NVME 0x0108
#define PCI_CLASS_STORAGE_OTHER 0x0180
#define PCI_BASE_CLASS_NETWORK 0x02