Patchwork [v3] NVMe: Initial commit

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Submitter Keith Busch
Date March 19, 2013, 7:41 p.m.
Message ID <1363722113-9276-1-git-send-email-keith.busch@intel.com>
Download mbox | patch
Permalink /patch/229213/
State New
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Comments

Keith Busch - March 19, 2013, 7:41 p.m.
Initial commit for emulated nvme pci device. Implements the minimum from
the specification to work with existing drivers.

Cc: Keith Busch <keith.busch@gmail.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>

Just going for the simplest patch possible for this device. If this is
okay, the remainining features implementing the full specification won't
be far behind.

I've incorporated all the comments received. The only thing I didn't see
how to make use of was the new initialization APIs; it doesn't look like
there is anything for me to do with this device in "instance_init".

Thanks for all the feedback!
---
 MAINTAINERS             |    5 +
 default-configs/pci.mak |    1 +
 hw/Makefile.objs        |    2 +
 hw/nvme.c               |  930 +++++++++++++++++++++++++++++++++++++++++++++++
 hw/nvme.h               |  713 ++++++++++++++++++++++++++++++++++++
 hw/pci/pci_ids.h        |    1 +
 6 files changed, 1652 insertions(+), 0 deletions(-)
 create mode 100644 hw/nvme.c
 create mode 100644 hw/nvme.h
Stefan Hajnoczi - March 20, 2013, 8:31 a.m.
On Tue, Mar 19, 2013 at 01:41:53PM -0600, Keith Busch wrote:
> +static int nvme_init(PCIDevice *pci_dev)
> +{
> +    NvmeCtrl *n = NVME(pci_dev);
> +    NvmeIdCtrl *id = &n->id_ctrl;
> +
> +    int i;
> +    int64_t bs_size;
> +    char serial[sizeof(id->sn)];
> +    uint8_t *pci_conf;
> +
> +    if (!(n->conf.bs)) {
> +        return -1;
> +    }
> +
> +    bs_size =  bdrv_getlength(n->conf.bs);
> +    if (bs_size <= 0) {
> +        return -1;
> +    }
> +
> +    n->instance = instance++;
> +    blkconf_serial(&n->conf, &n->serial);
> +    if (!n->serial) {
> +        snprintf((char *)serial, sizeof(serial), "NVMeQx10%02x", n->instance);
> +    }

A patch that adds serial autogeneration to virtio-blk was recently
posted.  Here were my concerns:

Autogenerated IDs have been proposed (for other devices?) before and I
think we should avoid them.

The autogenerated serial is not persistent.  It can change between QEMU
invocations - due to internal changes in QEMU or because the management
tool reordered -device options.

Users will be confused and their guests may stop working if they depend
on an ID like this.

The solution is to do persistent naming either by really passing -drive
serial= or with udev inside the guest using the bus address (PCI devfn)
like the new persistent network interface naming for Linux.

Stefan
Markus Armbruster - April 3, 2013, 7:52 a.m.
Stefan Hajnoczi <stefanha@gmail.com> writes:

> On Tue, Mar 19, 2013 at 01:41:53PM -0600, Keith Busch wrote:
>> +static int nvme_init(PCIDevice *pci_dev)
>> +{
>> +    NvmeCtrl *n = NVME(pci_dev);
>> +    NvmeIdCtrl *id = &n->id_ctrl;
>> +
>> +    int i;
>> +    int64_t bs_size;
>> +    char serial[sizeof(id->sn)];
>> +    uint8_t *pci_conf;
>> +
>> +    if (!(n->conf.bs)) {
>> +        return -1;
>> +    }
>> +
>> +    bs_size =  bdrv_getlength(n->conf.bs);
>> +    if (bs_size <= 0) {
>> +        return -1;
>> +    }
>> +
>> +    n->instance = instance++;
>> +    blkconf_serial(&n->conf, &n->serial);
>> +    if (!n->serial) {
>> + snprintf((char *)serial, sizeof(serial), "NVMeQx10%02x",
>> n->instance);
>> +    }
>
> A patch that adds serial autogeneration to virtio-blk was recently
> posted.  Here were my concerns:
>
> Autogenerated IDs have been proposed (for other devices?) before and I
> think we should avoid them.

ACK

> The autogenerated serial is not persistent.  It can change between QEMU
> invocations - due to internal changes in QEMU or because the management
> tool reordered -device options.
>
> Users will be confused and their guests may stop working if they depend
> on an ID like this.

Only IDE devices auto-generate their serial number.  Can't fix that
mistake, because it's ABI[*].  All other devices don't.  Let's keep it
that way.

> The solution is to do persistent naming either by really passing -drive
> serial= or with udev inside the guest using the bus address (PCI devfn)
> like the new persistent network interface naming for Linux.

ACK


[*] I could have avoided the mistake for ide-hd and ide-cd, but I didn't
see the problem then.  Perhaps we could've killed it for AHCI.

Patch

diff --git a/MAINTAINERS b/MAINTAINERS
index 0ca7e1d..9bd8956 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -585,6 +585,11 @@  S: Supported
 F: hw/virtio-serial*
 F: hw/virtio-console*
 
+nvme
+M: Keith Busch <keith.busch@intel.com>
+S: Supported
+F: hw/nvme*
+
 Xilinx EDK
 M: Peter Crosthwaite <peter.crosthwaite@petalogix.com>
 M: Edgar E. Iglesias <edgar.iglesias@gmail.com>
diff --git a/default-configs/pci.mak b/default-configs/pci.mak
index ee2d18d..56565e7 100644
--- a/default-configs/pci.mak
+++ b/default-configs/pci.mak
@@ -11,6 +11,7 @@  CONFIG_PCNET_PCI=y
 CONFIG_PCNET_COMMON=y
 CONFIG_LSI_SCSI_PCI=y
 CONFIG_MEGASAS_SCSI_PCI=y
+CONFIG_NVME_PCI=y
 CONFIG_RTL8139_PCI=y
 CONFIG_E1000_PCI=y
 CONFIG_IDE_CORE=y
diff --git a/hw/Makefile.objs b/hw/Makefile.objs
index 11812c6..b92d96f 100644
--- a/hw/Makefile.objs
+++ b/hw/Makefile.objs
@@ -46,6 +46,8 @@  common-obj-$(CONFIG_I8259) += i8259_common.o i8259.o
 common-obj-$(CONFIG_SDHCI) += sdhci.o
 common-obj-y += pam.o
 
+common-obj-$(CONFIG_NVME_PCI) += nvme.o
+
 # PPC devices
 common-obj-$(CONFIG_PREP_PCI) += prep_pci.o
 common-obj-$(CONFIG_I82378) += i82378.o
diff --git a/hw/nvme.c b/hw/nvme.c
new file mode 100644
index 0000000..2233b1d
--- /dev/null
+++ b/hw/nvme.c
@@ -0,0 +1,930 @@ 
+/*
+ * QEMU NVM Express Controller
+ *
+ * Copyright (c) 2012, Intel Corporation
+ *
+ * Written by Keith Busch <keith.busch@intel.com>
+ *
+ * This code is licensed under the GNU GPL v2 or later.
+ */
+
+/**
+ * Reference Specs: http://www.nvmexpress.org, 1.1, 1.0d
+ *
+ *  http://www.nvmexpress.org/index.php/download_file/view/102/1/
+ *  http://www.nvmexpress.org/index.php/download_file/view/100/1/
+ */
+
+/**
+ * Usage: add options:
+ *      -drive file=<file>,if=none,id=<drive_id>
+ *      -device nvme,drive=<drive_id>[,serial=<serial>,id=<dev_id>]
+ */
+
+#include "block-common.h"
+#include "hw.h"
+#include "pci/msix.h"
+#include "pci/pci.h"
+
+#include "nvme.h"
+
+static int instance;
+static void nvme_sq_process(void *opaque);
+
+static int nvme_check_sqid(NvmeCtrl *n, uint16_t sqid)
+{
+    return sqid < n->num_queues && n->sq[sqid] != NULL ? 0 : -1;
+}
+
+static int nvme_check_cqid(NvmeCtrl *n, uint16_t cqid)
+{
+    return cqid < n->num_queues && n->cq[cqid] != NULL ? 0 : -1;
+}
+
+static void nvme_inc_cq_tail(NvmeCQueue *cq)
+{
+    cq->tail++;
+    if (cq->tail >= cq->size) {
+        cq->tail = 0;
+        cq->phase = !cq->phase;
+    }
+}
+
+static void nvme_inc_sq_head(NvmeSQueue *sq)
+{
+    sq->head = (sq->head + 1) % sq->size;
+}
+
+static uint8_t nvme_cq_full(NvmeCQueue *cq)
+{
+    return (cq->tail + 1) % cq->size == cq->head;
+}
+
+static uint8_t nvme_sq_empty(NvmeSQueue *sq)
+{
+    return sq->head == sq->tail;
+}
+
+static void nvme_isr_notify(NvmeCtrl *n, NvmeCQueue *cq)
+{
+    if (cq->irq_enabled) {
+        if (msix_enabled(&(n->parent_obj))) {
+            msix_notify(&(n->parent_obj), cq->vector);
+        } else {
+            qemu_irq_pulse(n->parent_obj.irq[0]);
+        }
+    }
+}
+
+static uint16_t nvme_map_prp(QEMUSGList *qsg, 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;
+    }
+
+    qemu_sglist_init(qsg, num_prps, pci_dma_context(&n->parent_obj));
+    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);
+            pci_dma_read(&n->parent_obj, 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);
+                    pci_dma_read(&n->parent_obj, 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);
+                qemu_sglist_add(qsg, prp_ent, trans_len);
+                len -= trans_len;
+                i++;
+            }
+        } else {
+            if (prp2 & (n->page_size - 1)) {
+                goto unmap;
+            }
+            qemu_sglist_add(qsg, prp2, len);
+        }
+    }
+    return NVME_SUCCESS;
+
+ unmap:
+    qemu_sglist_destroy(qsg);
+    return NVME_INVALID_FIELD | NVME_DNR;
+}
+
+static uint16_t nvme_dma_write_prp(NvmeCtrl *n, uint8_t *ptr, uint32_t len,
+    uint64_t prp1, uint64_t prp2)
+{
+    QEMUSGList qsg;
+
+    if (nvme_map_prp(&qsg, prp1, prp2, len, n)) {
+        return NVME_INVALID_FIELD | NVME_DNR;
+    }
+    if (dma_buf_write(ptr, len, &qsg)) {
+        qemu_sglist_destroy(&qsg);
+        return NVME_INVALID_FIELD | NVME_DNR;
+    }
+    qemu_sglist_destroy(&qsg);
+    return NVME_SUCCESS;
+}
+
+static uint16_t nvme_dma_read_prp(NvmeCtrl *n, uint8_t *ptr, uint32_t len,
+    uint64_t prp1, uint64_t prp2)
+{
+    QEMUSGList qsg;
+
+    if (nvme_map_prp(&qsg, prp1, prp2, len, n)) {
+        return NVME_INVALID_FIELD | NVME_DNR;
+    }
+    if (dma_buf_read(ptr, len, &qsg)) {
+        qemu_sglist_destroy(&qsg);
+        return NVME_INVALID_FIELD | NVME_DNR;
+    }
+    return NVME_SUCCESS;
+}
+
+static void nvme_post_cqes(void *opaque)
+{
+    NvmeCQueue *cq = opaque;
+    NvmeCtrl *n = cq->ctrl;
+    NvmeRequest *req, *next;
+
+    QTAILQ_FOREACH_SAFE(req, &cq->req_list, entry, next) {
+        NvmeSQueue *sq;
+        hwaddr addr;
+
+        if (nvme_cq_full(cq)) {
+            break;
+        }
+
+        QTAILQ_REMOVE(&cq->req_list, req, entry);
+        sq = req->sq;
+        req->cqe.status = cpu_to_le16((req->status << 1) | cq->phase);
+        req->cqe.sq_id = cpu_to_le16(sq->sqid);
+        req->cqe.sq_head = cpu_to_le16(sq->head);
+        addr = cq->dma_addr + cq->tail * n->cqe_size;
+        nvme_inc_cq_tail(cq);
+        pci_dma_write(&n->parent_obj, addr, (void *)&req->cqe,
+            sizeof(req->cqe));
+        QTAILQ_INSERT_TAIL(&sq->req_list, req, entry);
+        nvme_isr_notify(n, cq);
+    }
+}
+
+static void nvme_enqueue_req_completion(NvmeCQueue *cq, NvmeRequest *req)
+{
+    assert(cq->cqid == req->sq->cqid);
+    QTAILQ_REMOVE(&req->sq->out_req_list, req, entry);
+    QTAILQ_INSERT_TAIL(&cq->req_list, req, entry);
+    qemu_mod_timer(cq->timer, qemu_get_clock_ns(vm_clock) + 500);
+}
+
+static void nvme_rw_cb(void *opaque, int ret)
+{
+    NvmeRequest *req = opaque;
+    NvmeSQueue *sq = req->sq;
+    NvmeCtrl *n = sq->ctrl;
+    NvmeCQueue *cq = n->cq[sq->cqid];
+
+    qemu_sglist_destroy(&req->qsg);
+    if (!ret) {
+        req->status = NVME_SUCCESS;
+    } else {
+        req->status = NVME_INTERNAL_DEV_ERROR;
+    }
+    nvme_enqueue_req_completion(cq, req);
+}
+
+static uint16_t nvme_rw(NvmeCtrl *n, NvmeNamespace *ns, NvmeCmd *cmd,
+    NvmeRequest *req)
+{
+    NvmeRwCmd *rw = (NvmeRwCmd *)cmd;
+    uint32_t nlb  = le32_to_cpu(rw->nlb) + 1;
+    uint64_t slba = le64_to_cpu(rw->slba);
+    uint64_t prp1 = le64_to_cpu(rw->prp1);
+    uint64_t prp2 = le64_to_cpu(rw->prp2);
+
+    uint8_t lba_index  = NVME_ID_NS_FLBAS_INDEX(ns->id_ns.flbas);
+    uint8_t data_shift = ns->id_ns.lbaf[lba_index].ds;
+    uint64_t data_size = nlb << data_shift;
+    uint64_t aio_slba  = ns->start_block + (slba << (data_shift -
+        BDRV_SECTOR_BITS));
+
+    if ((slba + nlb) > ns->id_ns.nsze) {
+        return NVME_LBA_RANGE | NVME_DNR;
+    }
+
+    if (nvme_map_prp(&req->qsg, prp1, prp2, data_size, n)) {
+        return NVME_INVALID_FIELD | NVME_DNR;
+    }
+    assert((nlb << data_shift) == req->qsg.size);
+
+    req->aiocb = rw->opcode == NVME_CMD_WRITE ?
+        dma_bdrv_write(n->conf.bs, &req->qsg, aio_slba, nvme_rw_cb, req) :
+        dma_bdrv_read(n->conf.bs, &req->qsg, aio_slba, nvme_rw_cb, req);
+
+    return NVME_NO_COMPLETE;
+}
+
+static uint16_t nvme_io_cmd(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
+{
+    NvmeNamespace *ns;
+    uint32_t nsid = le32_to_cpu(cmd->nsid);
+
+    if (nsid == 0 || nsid > n->num_namespaces) {
+        return NVME_INVALID_NSID | NVME_DNR;
+    }
+
+    ns = &n->namespaces[nsid - 1];
+    switch (cmd->opcode) {
+    case NVME_CMD_FLUSH:
+        return NVME_SUCCESS;
+    case NVME_CMD_WRITE:
+    case NVME_CMD_READ:
+        return nvme_rw(n, ns, cmd, req);
+    default:
+        return NVME_INVALID_OPCODE | NVME_DNR;
+    }
+}
+
+static void nvme_free_sq(NvmeSQueue *sq, NvmeCtrl *n)
+{
+    n->sq[sq->sqid] = NULL;
+    qemu_del_timer(sq->timer);
+    qemu_free_timer(sq->timer);
+    g_free(sq->io_req);
+    if (sq->sqid) {
+        g_free(sq);
+    }
+}
+
+static uint16_t nvme_del_sq(NvmeCtrl *n, NvmeCmd *cmd)
+{
+    NvmeDeleteQ *c = (NvmeDeleteQ *)cmd;
+    NvmeRequest *req, *next;
+    NvmeSQueue *sq;
+    NvmeCQueue *cq;
+    uint16_t qid = le16_to_cpu(c->qid);
+
+    if (!qid || nvme_check_sqid(n, qid)) {
+        return NVME_INVALID_QID | NVME_DNR;
+    }
+
+    sq = n->sq[qid];
+    while (!QTAILQ_EMPTY(&sq->out_req_list)) {
+        req = QTAILQ_FIRST(&sq->out_req_list);
+        assert(req->aiocb);
+        bdrv_aio_cancel(req->aiocb);
+    }
+    if (!nvme_check_cqid(n, sq->cqid)) {
+        cq = n->cq[sq->cqid];
+        QTAILQ_REMOVE(&cq->sq_list, sq, entry);
+
+        nvme_post_cqes(cq);
+        QTAILQ_FOREACH_SAFE(req, &cq->req_list, entry, next) {
+            if (req->sq == sq) {
+                QTAILQ_REMOVE(&cq->req_list, req, entry);
+                QTAILQ_INSERT_TAIL(&sq->req_list, req, entry);
+            }
+        }
+    }
+
+    nvme_free_sq(sq, n);
+    return NVME_SUCCESS;
+}
+
+static void nvme_init_sq(NvmeSQueue *sq, NvmeCtrl *n, uint64_t dma_addr,
+    uint16_t sqid, uint16_t cqid, uint16_t size)
+{
+    int i;
+    NvmeCQueue *cq;
+
+    sq->ctrl = n;
+    sq->dma_addr = dma_addr;
+    sq->sqid = sqid;
+    sq->size = size;
+    sq->cqid = cqid;
+    sq->head = sq->tail = 0;
+    sq->io_req = g_malloc(sq->size * sizeof(*sq->io_req));
+
+    QTAILQ_INIT(&sq->req_list);
+    QTAILQ_INIT(&sq->out_req_list);
+    for (i = 0; i < sq->size; i++) {
+        sq->io_req[i].sq = sq;
+        QTAILQ_INSERT_TAIL(&(sq->req_list), &sq->io_req[i], entry);
+    }
+    sq->timer = qemu_new_timer_ns(vm_clock, nvme_sq_process, sq);
+
+    assert(n->cq[cqid]);
+    cq = n->cq[cqid];
+    QTAILQ_INSERT_TAIL(&(cq->sq_list), sq, entry);
+
+    n->sq[sqid] = sq;
+}
+
+static uint16_t nvme_create_sq(NvmeCtrl *n, NvmeCmd *cmd)
+{
+    NvmeSQueue *sq;
+    NvmeCreateSq *c = (NvmeCreateSq *)cmd;
+
+    uint16_t cqid = le16_to_cpu(c->cqid);
+    uint16_t sqid = le16_to_cpu(c->sqid);
+    uint16_t qsize = le16_to_cpu(c->qsize);
+    uint16_t qflags = le16_to_cpu(c->sq_flags);
+    uint64_t prp1 = le64_to_cpu(c->prp1);
+
+    if (!cqid || nvme_check_cqid(n, cqid)) {
+        return NVME_INVALID_CQID | NVME_DNR;
+    }
+    if (!sqid || (sqid && !nvme_check_sqid(n, sqid))) {
+        return NVME_INVALID_QID | NVME_DNR;
+    }
+    if (!qsize || qsize > NVME_CAP_MQES(n->bar.cap)) {
+        return NVME_MAX_QSIZE_EXCEEDED | NVME_DNR;
+    }
+    if (!prp1 || prp1 & (n->page_size - 1)) {
+        return NVME_INVALID_FIELD | NVME_DNR;
+    }
+    if (!(NVME_SQ_FLAGS_PC(qflags))) {
+        return NVME_INVALID_FIELD | NVME_DNR;
+    }
+    sq = g_malloc0(sizeof(*sq));
+    nvme_init_sq(sq, n, prp1, sqid, cqid, qsize + 1);
+    return NVME_SUCCESS;
+}
+
+static void nvme_free_cq(NvmeCQueue *cq, NvmeCtrl *n)
+{
+    n->cq[cq->cqid] = NULL;
+    qemu_del_timer(cq->timer);
+    qemu_free_timer(cq->timer);
+    msix_vector_unuse(&n->parent_obj, cq->vector);
+    if (cq->cqid) {
+        g_free(cq);
+    }
+}
+
+static uint16_t nvme_del_cq(NvmeCtrl *n, NvmeCmd *cmd)
+{
+    NvmeDeleteQ *c = (NvmeDeleteQ *)cmd;
+    NvmeCQueue *cq;
+    uint16_t qid = le16_to_cpu(c->qid);
+
+    if (!qid || nvme_check_cqid(n, qid)) {
+        return NVME_INVALID_CQID | NVME_DNR;
+    }
+
+    cq = n->cq[qid];
+    if (!QTAILQ_EMPTY(&cq->sq_list)) {
+        return NVME_INVALID_QUEUE_DEL;
+    }
+    nvme_free_cq(cq, n);
+    return NVME_SUCCESS;
+}
+
+static void nvme_init_cq(NvmeCQueue *cq, NvmeCtrl *n, uint64_t dma_addr,
+    uint16_t cqid, uint16_t vector, uint16_t size, uint16_t irq_enabled)
+{
+    cq->ctrl = n;
+    cq->cqid = cqid;
+    cq->size = size;
+    cq->dma_addr = dma_addr;
+    cq->phase = 1;
+    cq->irq_enabled = irq_enabled;
+    cq->vector = vector;
+    cq->head = cq->tail = 0;
+    QTAILQ_INIT(&cq->req_list);
+    QTAILQ_INIT(&cq->sq_list);
+    msix_vector_use(&n->parent_obj, cq->vector);
+    n->cq[cqid] = cq;
+    cq->timer = qemu_new_timer_ns(vm_clock, nvme_post_cqes, cq);
+}
+
+static uint16_t nvme_create_cq(NvmeCtrl *n, NvmeCmd *cmd)
+{
+    NvmeCQueue *cq;
+    NvmeCreateCq *c = (NvmeCreateCq *)cmd;
+    uint16_t cqid = le16_to_cpu(c->cqid);
+    uint16_t vector = le16_to_cpu(c->irq_vector);
+    uint16_t qsize = le16_to_cpu(c->qsize);
+    uint16_t qflags = le16_to_cpu(c->cq_flags);
+    uint64_t prp1 = le64_to_cpu(c->prp1);
+
+    if (!cqid || (cqid && !nvme_check_cqid(n, cqid))) {
+        return NVME_INVALID_CQID | NVME_DNR;
+    }
+    if (!qsize || qsize > NVME_CAP_MQES(n->bar.cap)) {
+        return NVME_MAX_QSIZE_EXCEEDED | NVME_DNR;
+    }
+    if (!prp1) {
+        return NVME_INVALID_FIELD | NVME_DNR;
+    }
+    if (vector > n->num_queues) {
+        return NVME_INVALID_IRQ_VECTOR;
+    }
+    if (!(NVME_CQ_FLAGS_PC(qflags))) {
+        return NVME_INVALID_FIELD | NVME_DNR;
+    }
+
+    cq = g_malloc0(sizeof(*cq));
+    nvme_init_cq(cq, n, prp1, cqid, vector, qsize + 1,
+        NVME_CQ_FLAGS_IEN(qflags));
+    return NVME_SUCCESS;
+}
+
+static uint16_t nvme_identify(NvmeCtrl *n, NvmeCmd *cmd)
+{
+    NvmeNamespace *ns;
+    NvmeIdentify *c = (NvmeIdentify *)cmd;
+    uint32_t cns  = le32_to_cpu(c->cns);
+    uint32_t nsid = le32_to_cpu(c->nsid);
+    uint64_t prp1 = le64_to_cpu(c->prp1);
+    uint64_t prp2 = le64_to_cpu(c->prp2);
+
+    if (cns) {
+        return nvme_dma_read_prp(n, (uint8_t *)&n->id_ctrl, sizeof(n->id_ctrl),
+            prp1, prp2);
+    }
+
+    if (nsid == 0 || nsid > n->num_namespaces) {
+        return NVME_INVALID_NSID | NVME_DNR;
+    }
+    ns = &n->namespaces[nsid - 1];
+    return nvme_dma_read_prp(n, (uint8_t *)&ns->id_ns, sizeof(ns->id_ns),
+        prp1, prp2);
+}
+
+static uint16_t nvme_get_feature(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
+{
+    NvmeRangeType *rt;
+    uint32_t dw10 = le32_to_cpu(cmd->cdw10);
+    uint32_t dw11 = le32_to_cpu(cmd->cdw11);
+    uint32_t nsid = le32_to_cpu(cmd->nsid);
+    uint64_t prp1 = le64_to_cpu(cmd->prp1);
+    uint64_t prp2 = le64_to_cpu(cmd->prp2);
+
+    switch (dw10) {
+    case NVME_LBA_RANGE_TYPE:
+        if (nsid == 0 || nsid > n->num_namespaces) {
+            return NVME_INVALID_NSID | NVME_DNR;
+        }
+        rt = n->namespaces[nsid - 1].lba_range;
+        return nvme_dma_read_prp(n, (uint8_t *)rt,
+            MIN(sizeof(*rt), (dw11 & 0x3f) * sizeof(*rt)),
+            prp1, prp2);
+    case NVME_NUMBER_OF_QUEUES:
+        req->cqe.result = cpu_to_le32(n->num_queues);
+        break;
+    default:
+        return NVME_INVALID_FIELD | NVME_DNR;
+    }
+    return NVME_SUCCESS;
+}
+
+static uint16_t nvme_set_feature(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
+{
+    NvmeRangeType *rt;
+    uint32_t dw10 = le32_to_cpu(cmd->cdw10);
+    uint32_t dw11 = le32_to_cpu(cmd->cdw11);
+    uint32_t nsid = le32_to_cpu(cmd->nsid);
+    uint64_t prp1 = le64_to_cpu(cmd->prp1);
+    uint64_t prp2 = le64_to_cpu(cmd->prp2);
+
+    switch (dw10) {
+    case NVME_LBA_RANGE_TYPE:
+        if (nsid == 0 || nsid > n->num_namespaces) {
+            return NVME_INVALID_NSID | NVME_DNR;
+        }
+        rt = n->namespaces[nsid - 1].lba_range;
+        return nvme_dma_write_prp(n, (uint8_t *)rt,
+            MIN(sizeof(*rt), (dw11 & 0x3f) * sizeof(*rt)),
+            prp1, prp2);
+    case NVME_NUMBER_OF_QUEUES:
+        req->cqe.result = cpu_to_le32(n->num_queues);
+        break;
+    default:
+        return NVME_INVALID_FIELD | NVME_DNR;
+    }
+    return NVME_SUCCESS;
+}
+
+static uint16_t nvme_admin_cmd(NvmeCtrl *n, NvmeCmd *cmd, NvmeRequest *req)
+{
+    switch (cmd->opcode) {
+    case NVME_ADM_CMD_DELETE_SQ:
+        return nvme_del_sq(n, cmd);
+    case NVME_ADM_CMD_CREATE_SQ:
+        return nvme_create_sq(n, cmd);
+    case NVME_ADM_CMD_DELETE_CQ:
+        return nvme_del_cq(n, cmd);
+    case NVME_ADM_CMD_CREATE_CQ:
+        return nvme_create_cq(n, cmd);
+    case NVME_ADM_CMD_IDENTIFY:
+        return nvme_identify(n, cmd);
+    case NVME_ADM_CMD_SET_FEATURES:
+        return nvme_set_feature(n, cmd, req);
+    case NVME_ADM_CMD_GET_FEATURES:
+        return nvme_get_feature(n, cmd, req);
+    default:
+        return NVME_INVALID_OPCODE | NVME_DNR;
+    }
+}
+
+static void nvme_sq_process(void *opaque)
+{
+    uint16_t status;
+    hwaddr addr;
+    NvmeCmd cmd;
+    NvmeRequest *req;
+    NvmeSQueue *sq = opaque;
+    NvmeCtrl *n = sq->ctrl;
+    NvmeCQueue *cq = n->cq[sq->cqid];
+
+    while (!(nvme_sq_empty(sq) || QTAILQ_EMPTY(&sq->req_list))) {
+        addr = sq->dma_addr + sq->head * n->sqe_size;
+        pci_dma_read(&n->parent_obj, addr, (void *)&cmd, sizeof(cmd));
+        nvme_inc_sq_head(sq);
+
+        req = QTAILQ_FIRST(&sq->req_list);
+        QTAILQ_REMOVE(&sq->req_list, req, entry);
+        QTAILQ_INSERT_TAIL(&sq->out_req_list, req, entry);
+        memset(&req->cqe, 0, sizeof(req->cqe));
+        req->cqe.cid = cmd.cid;
+
+        status = sq->sqid ? nvme_io_cmd(n, &cmd, req) :
+            nvme_admin_cmd(n, &cmd, req);
+        if (status != NVME_NO_COMPLETE) {
+            req->status = status;
+            nvme_enqueue_req_completion(cq, req);
+        }
+    }
+}
+
+static void nvme_clear_ctrl(NvmeCtrl *n)
+{
+    int i;
+
+    for (i = 0; i < n->num_queues; i++) {
+        if (n->sq[i] != NULL) {
+            nvme_free_sq(n->sq[i], n);
+        }
+    }
+    for (i = 0; i < n->num_queues; i++) {
+        if (n->cq[i] != NULL) {
+            nvme_free_cq(n->cq[i], n);
+        }
+    }
+    n->bar.cc = 0;
+}
+
+static int nvme_start_ctrl(NvmeCtrl *n)
+{
+    uint32_t page_bits = NVME_CC_MPS(n->bar.cc) + 12;
+    uint32_t page_size = 1 << page_bits;
+
+    if (n->cq[0] || n->sq[0] || !n->bar.asq || !n->bar.acq ||
+            n->bar.asq & (page_size - 1) || n->bar.acq & (page_size - 1) ||
+            NVME_CC_MPS(n->bar.cc) < NVME_CAP_MPSMIN(n->bar.cap) ||
+            NVME_CC_MPS(n->bar.cc) > NVME_CAP_MPSMAX(n->bar.cap) ||
+            NVME_CC_IOCQES(n->bar.cc) < NVME_CTRL_CQES_MIN(n->id_ctrl.cqes) ||
+            NVME_CC_IOCQES(n->bar.cc) > NVME_CTRL_CQES_MAX(n->id_ctrl.cqes) ||
+            NVME_CC_IOSQES(n->bar.cc) < NVME_CTRL_SQES_MIN(n->id_ctrl.sqes) ||
+            NVME_CC_IOSQES(n->bar.cc) > NVME_CTRL_SQES_MAX(n->id_ctrl.sqes) ||
+            !NVME_AQA_ASQS(n->bar.aqa) || NVME_AQA_ASQS(n->bar.aqa) > 4095 ||
+            !NVME_AQA_ACQS(n->bar.aqa) || NVME_AQA_ACQS(n->bar.aqa) > 4095) {
+        return -1;
+    }
+
+    n->page_bits = NVME_CC_MPS(n->bar.cc) + 12;
+    n->page_size = 1 << n->page_bits;
+    n->max_prp_ents = n->page_size / sizeof(uint64_t);
+    n->cqe_size = 1 << NVME_CC_IOCQES(n->bar.cc);
+    n->sqe_size = 1 << NVME_CC_IOSQES(n->bar.cc);
+    nvme_init_cq(&n->admin_cq, n, n->bar.acq, 0, 0,
+        NVME_AQA_ACQS(n->bar.aqa) + 1, 1);
+    nvme_init_sq(&n->admin_sq, n, n->bar.asq, 0, 0,
+        NVME_AQA_ASQS(n->bar.aqa) + 1);
+
+    return 0;
+}
+
+static void nvme_write_bar(NvmeCtrl *n, hwaddr offset, uint64_t data,
+    unsigned size)
+{
+    switch (offset) {
+    case 0xc:
+        n->bar.intms |= data & 0xffffffff;
+        n->bar.intmc = n->bar.intms;
+        break;
+    case 0x10:
+        n->bar.intms &= ~(data & 0xffffffff);
+        n->bar.intmc = n->bar.intms;
+        break;
+    case 0x14:
+        if (NVME_CC_EN(data) && !NVME_CC_EN(n->bar.cc)) {
+            n->bar.cc = data;
+            if (nvme_start_ctrl(n)) {
+                n->bar.csts = NVME_CSTS_FAILED;
+            } else {
+                n->bar.csts = NVME_CSTS_READY;
+            }
+        } else if (!NVME_CC_EN(data) && NVME_CC_EN(n->bar.cc)) {
+            nvme_clear_ctrl(n);
+            n->bar.csts &= ~NVME_CSTS_READY;
+        }
+        if (NVME_CC_SHN(data) && !(NVME_CC_SHN(n->bar.cc))) {
+                nvme_clear_ctrl(n);
+                n->bar.cc = data;
+                n->bar.csts |= NVME_CSTS_SHST_COMPLETE;
+        } else if (!NVME_CC_SHN(data) && NVME_CC_SHN(n->bar.cc)) {
+                n->bar.csts &= ~NVME_CSTS_SHST_COMPLETE;
+                n->bar.cc = data;
+        }
+        break;
+    case 0x24:
+        n->bar.aqa = data & 0xffffffff;
+        break;
+    case 0x28:
+        n->bar.asq = data;
+        break;
+    case 0x2c:
+        n->bar.asq |= data << 32;
+        break;
+    case 0x30:
+        n->bar.acq = data;
+        break;
+    case 0x34:
+        n->bar.acq |= data << 32;
+        break;
+    }
+}
+
+static uint64_t nvme_mmio_read(void *opaque, hwaddr addr, unsigned size)
+{
+    NvmeCtrl *n = (NvmeCtrl *)opaque;
+    uint8_t *ptr = (uint8_t *)&n->bar;
+    uint64_t val = 0;
+
+    if (addr < sizeof(n->bar)) {
+        memcpy(&val, ptr + addr, size);
+    }
+    return val;
+}
+
+static void nvme_process_db(NvmeCtrl *n, hwaddr addr, int val)
+{
+    uint32_t qid;
+
+    if (addr & ((1 << 2) - 1)) {
+        return;
+    }
+
+    if (((addr - 0x1000) >> 2) & 1) {
+        uint16_t new_head = val & 0xffff;
+        NvmeCQueue *cq;
+        int start_sqs;
+
+        qid = (addr - (0x1000 + (1 << 2))) >> 3;
+        if (nvme_check_cqid(n, qid)) {
+            return;
+        }
+
+        cq = n->cq[qid];
+        if (new_head >= cq->size) {
+            return;
+        }
+
+        start_sqs = nvme_cq_full(cq) ? 1 : 0;
+        cq->head = new_head;
+        if (start_sqs) {
+            NvmeSQueue *sq;
+            QTAILQ_FOREACH(sq, &cq->sq_list, entry) {
+                qemu_mod_timer(sq->timer, qemu_get_clock_ns(vm_clock) + 500);
+            }
+            qemu_mod_timer(cq->timer, qemu_get_clock_ns(vm_clock) + 500);
+        }
+
+        if (cq->tail != cq->head) {
+            nvme_isr_notify(n, cq);
+        }
+    } else {
+        uint16_t new_tail = val & 0xffff;
+        NvmeSQueue *sq;
+
+        qid = (addr - 0x1000) >> 3;
+        if (nvme_check_sqid(n, qid)) {
+            return;
+        }
+
+        sq = n->sq[qid];
+        if (new_tail >= sq->size) {
+            return;
+        }
+
+        sq->tail = new_tail;
+        qemu_mod_timer(sq->timer, qemu_get_clock_ns(vm_clock) + 500);
+    }
+}
+
+static void nvme_mmio_write(void *opaque, hwaddr addr, uint64_t data,
+    unsigned size)
+{
+    NvmeCtrl *n = (NvmeCtrl *)opaque;
+    if (addr < sizeof(n->bar)) {
+        nvme_write_bar(n, addr, data, size);
+    } else if (addr >= 0x1000) {
+        nvme_process_db(n, addr, data);
+    }
+}
+
+static const MemoryRegionOps nvme_mmio_ops = {
+    .read = nvme_mmio_read,
+    .write = nvme_mmio_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .impl = {
+        .min_access_size = 2,
+        .max_access_size = 8,
+    },
+};
+
+static int nvme_init(PCIDevice *pci_dev)
+{
+    NvmeCtrl *n = NVME(pci_dev);
+    NvmeIdCtrl *id = &n->id_ctrl;
+
+    int i;
+    int64_t bs_size;
+    char serial[sizeof(id->sn)];
+    uint8_t *pci_conf;
+
+    if (!(n->conf.bs)) {
+        return -1;
+    }
+
+    bs_size =  bdrv_getlength(n->conf.bs);
+    if (bs_size <= 0) {
+        return -1;
+    }
+
+    n->instance = instance++;
+    blkconf_serial(&n->conf, &n->serial);
+    if (!n->serial) {
+        snprintf((char *)serial, sizeof(serial), "NVMeQx10%02x", n->instance);
+    }
+
+    pci_conf = pci_dev->config;
+    pci_conf[PCI_INTERRUPT_PIN] = 1;
+    pci_config_set_prog_interface(pci_dev->config, 0x2);
+    pci_config_set_class(pci_dev->config, PCI_CLASS_STORAGE_EXPRESS);
+
+    n->num_namespaces = 1;
+    n->num_queues = 64;
+    n->reg_size = 1 << qemu_fls(0x1004 + 2 * (n->num_queues + 1) * 4);
+    n->ns_size = bs_size / n->num_namespaces;
+
+    n->namespaces = g_malloc0(sizeof(*n->namespaces)*n->num_namespaces);
+    n->sq = g_malloc0(sizeof(*n->sq)*n->num_queues);
+    n->cq = g_malloc0(sizeof(*n->cq)*n->num_queues);
+
+    memory_region_init_io(&n->iomem, &nvme_mmio_ops, n, "nvme", n->reg_size);
+    pci_register_bar(&n->parent_obj, 0,
+        PCI_BASE_ADDRESS_SPACE_MEMORY | PCI_BASE_ADDRESS_MEM_TYPE_64,
+        &n->iomem);
+    msix_init_exclusive_bar(&n->parent_obj, n->num_queues, 4);
+
+    id->vid = cpu_to_le16(pci_get_word(pci_conf + PCI_VENDOR_ID));
+    id->ssvid = cpu_to_le16(pci_get_word(pci_conf + PCI_SUBSYSTEM_VENDOR_ID));
+
+    strpadcpy((char *)id->mn, sizeof(id->mn), "QEMU NVMe Ctrl", ' ');
+    strpadcpy((char *)id->fr, sizeof(id->fr), "1.0", ' ');
+    strpadcpy((char *)id->sn, sizeof(id->sn),
+            n->serial ? n->serial : serial, ' ');
+
+    id->rab = 6;
+    id->ieee[0] = 0x00;
+    id->ieee[1] = 0x02;
+    id->ieee[2] = 0xb3;
+    id->oacs = cpu_to_le16(0);
+    id->frmw = 7 << 1;
+    id->sqes = (0x6 << 4) | 0x6;
+    id->cqes = (0x4 << 4) | 0x4;
+    id->nn = cpu_to_le32(n->num_namespaces);
+    id->psd[0].mp = cpu_to_le16(0x9c4);
+    id->psd[0].enlat = cpu_to_le32(0x10);
+    id->psd[0].exlat = cpu_to_le32(0x4);
+
+    NVME_CAP_SET_MQES(n->bar.cap, 0x7ff);
+    NVME_CAP_SET_CQR(n->bar.cap, 1);
+    NVME_CAP_SET_AMS(n->bar.cap, 1);
+    NVME_CAP_SET_TO(n->bar.cap, 0xf);
+    NVME_CAP_SET_DSTRD(n->bar.cap, 0);
+    NVME_CAP_SET_NSSRS(n->bar.cap, 0);
+    NVME_CAP_SET_CSS(n->bar.cap, 1);
+    NVME_CAP_SET_MPSMIN(n->bar.cap, 0);
+    NVME_CAP_SET_MPSMAX(n->bar.cap, 0);
+
+    n->bar.vs = 0x00010001;
+
+    for (i = 0; i < n->num_namespaces; i++) {
+        NvmeNamespace *ns = &n->namespaces[i];
+        NvmeIdNs *id_ns = &ns->id_ns;
+        id_ns->lbaf[0].ds = BDRV_SECTOR_BITS;
+        id_ns->ncap  = id_ns->nuse = id_ns->nsze =
+            cpu_to_le64(n->ns_size >>
+                id_ns->lbaf[NVME_ID_NS_FLBAS_INDEX(ns->id_ns.flbas)].ds);
+        ns->start_block = (n->ns_size >> BDRV_SECTOR_BITS) * i;
+    }
+
+    return 0;
+}
+
+static void nvme_exit(PCIDevice *pci_dev)
+{
+    NvmeCtrl *n = NVME(pci_dev);
+
+    nvme_clear_ctrl(n);
+    g_free(n->namespaces);
+    g_free(n->cq);
+    g_free(n->sq);
+    msix_uninit_exclusive_bar(pci_dev);
+    memory_region_destroy(&n->iomem);
+}
+
+static Property nvme_props[] = {
+    DEFINE_BLOCK_PROPERTIES(NvmeCtrl, conf),
+    DEFINE_PROP_STRING("serial", NvmeCtrl, serial),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static const VMStateDescription nvme_vmstate = {
+    .name = "nvme",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .minimum_version_id_old = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_PCI_DEVICE(parent_obj, NvmeCtrl),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static void nvme_class_init(ObjectClass *oc, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(oc);
+    PCIDeviceClass *pc = PCI_DEVICE_CLASS(oc);
+
+    pc->init = nvme_init;
+    pc->exit = nvme_exit;
+    pc->class_id = PCI_CLASS_STORAGE_EXPRESS;
+    pc->vendor_id = PCI_VENDOR_ID_INTEL;
+    pc->device_id = 0x5845;
+    pc->subsystem_vendor_id = PCI_VENDOR_ID_INTEL;
+    pc->subsystem_id = 0x1234;
+    pc->revision = 1;
+
+    dc->desc = "Non-Volatile Memory Express";
+    dc->props = nvme_props;
+    dc->vmsd = &nvme_vmstate;
+}
+
+static const TypeInfo nvme_info = {
+    .name          = TYPE_NVME,
+    .parent        = TYPE_PCI_DEVICE,
+    .instance_size = sizeof(NvmeCtrl),
+    .class_init    = nvme_class_init,
+};
+
+static void nvme_register_types(void)
+{
+    type_register_static(&nvme_info);
+}
+
+type_init(nvme_register_types)
diff --git a/hw/nvme.h b/hw/nvme.h
new file mode 100644
index 0000000..3cf22f9
--- /dev/null
+++ b/hw/nvme.h
@@ -0,0 +1,713 @@ 
+#ifndef HW_NVME_H
+#define HW_NVME_H
+
+typedef struct NvmeBar {
+    uint64_t    cap;
+    uint32_t    vs;
+    uint32_t    intms;
+    uint32_t    intmc;
+    uint32_t    cc;
+    uint32_t    rsvd1;
+    uint32_t    csts;
+    uint32_t    nssrc;
+    uint32_t    aqa;
+    uint64_t    asq;
+    uint64_t    acq;
+} NvmeBar;
+
+enum NvmeCapShift {
+    CAP_MQES_SHIFT     = 0,
+    CAP_CQR_SHIFT      = 16,
+    CAP_AMS_SHIFT      = 17,
+    CAP_TO_SHIFT       = 24,
+    CAP_DSTRD_SHIFT    = 32,
+    CAP_NSSRS_SHIFT    = 33,
+    CAP_CSS_SHIFT      = 37,
+    CAP_MPSMIN_SHIFT   = 48,
+    CAP_MPSMAX_SHIFT   = 52,
+};
+
+enum NvmeCapMask {
+    CAP_MQES_MASK      = 0xffff,
+    CAP_CQR_MASK       = 0x1,
+    CAP_AMS_MASK       = 0x3,
+    CAP_TO_MASK        = 0xff,
+    CAP_DSTRD_MASK     = 0xf,
+    CAP_NSSRS_MASK     = 0x1,
+    CAP_CSS_MASK       = 0xff,
+    CAP_MPSMIN_MASK    = 0xf,
+    CAP_MPSMAX_MASK    = 0xf,
+};
+
+#define NVME_CAP_MQES(cap)  (((cap) >> CAP_MQES_SHIFT)   & CAP_MQES_MASK)
+#define NVME_CAP_CQR(cap)   (((cap) >> CAP_CQR_SHIFT)    & CAP_CQR_MASK)
+#define NVME_CAP_AMS(cap)   (((cap) >> CAP_AMS_SHIFT)    & CAP_AMS_MASK)
+#define NVME_CAP_TO(cap)    (((cap) >> CAP_TO_SHIFT)     & CAP_TO_MASK)
+#define NVME_CAP_DSTRD(cap) (((cap) >> CAP_DSTRD_SHIFT)  & CAP_DSTRD_MASK)
+#define NVME_CAP_NSSRS(cap) (((cap) >> CAP_NSSRS_SHIFT)  & CAP_NSSRS_MASK)
+#define NVME_CAP_CSS(cap)   (((cap) >> CAP_CSS_SHIFT)    & CAP_CSS_MASK)
+#define NVME_CAP_MPSMIN(cap)(((cap) >> CAP_MPSMIN_SHIFT) & CAP_MPSMIN_MASK)
+#define NVME_CAP_MPSMAX(cap)(((cap) >> CAP_MPSMAX_SHIFT) & CAP_MPSMAX_MASK)
+
+#define NVME_CAP_SET_MQES(cap, val) \
+    (cap |= (uint64_t)(val & CAP_MQES_MASK) << CAP_MQES_SHIFT)
+#define NVME_CAP_SET_CQR(cap, val) \
+    (cap |= (uint64_t)(val & CAP_CQR_MASK) << CAP_CQR_SHIFT)
+#define NVME_CAP_SET_AMS(cap, val) \
+    (cap |= (uint64_t)(val & CAP_AMS_MASK) << CAP_AMS_SHIFT)
+#define NVME_CAP_SET_TO(cap, val) \
+    (cap |= (uint64_t)(val & CAP_TO_MASK) << CAP_TO_SHIFT)
+#define NVME_CAP_SET_DSTRD(cap, val) \
+    (cap |= (uint64_t)(val & CAP_DSTRD_MASK) << CAP_DSTRD_SHIFT)
+#define NVME_CAP_SET_NSSRS(cap, val) \
+    (cap |= (uint64_t)(val & CAP_NSSRS_MASK) << CAP_NSSRS_SHIFT)
+#define NVME_CAP_SET_CSS(cap, val) \
+    (cap |= (uint64_t)(val & CAP_CSS_MASK) << CAP_CSS_SHIFT)
+#define NVME_CAP_SET_MPSMIN(cap, val) \
+    (cap |= (uint64_t)(val & CAP_MPSMIN_MASK) << CAP_MPSMIN_SHIFT)
+#define NVME_CAP_SET_MPSMAX(cap, val) \
+    (cap |= (uint64_t)(val & CAP_MPSMAX_MASK) << CAP_MPSMAX_SHIFT)
+
+enum NvmeCcShift {
+    CC_EN_SHIFT     = 0,
+    CC_CSS_SHIFT    = 4,
+    CC_MPS_SHIFT    = 7,
+    CC_AMS_SHIFT    = 11,
+    CC_SHN_SHIFT    = 14,
+    CC_IOSQES_SHIFT = 16,
+    CC_IOCQES_SHIFT = 20,
+};
+
+enum NvmeCcMask {
+    CC_EN_MASK      = 0x1,
+    CC_CSS_MASK     = 0x7,
+    CC_MPS_MASK     = 0xf,
+    CC_AMS_MASK     = 0x7,
+    CC_SHN_MASK     = 0x3,
+    CC_IOSQES_MASK  = 0xf,
+    CC_IOCQES_MASK  = 0xf,
+};
+
+#define NVME_CC_EN(cc)     ((cc >> CC_EN_SHIFT)     & CC_EN_MASK)
+#define NVME_CC_CSS(cc)    ((cc >> CC_CSS_SHIFT)    & CC_CSS_MASK)
+#define NVME_CC_MPS(cc)    ((cc >> CC_MPS_SHIFT)    & CC_MPS_MASK)
+#define NVME_CC_AMS(cc)    ((cc >> CC_AMS_SHIFT)    & CC_AMS_MASK)
+#define NVME_CC_SHN(cc)    ((cc >> CC_SHN_SHIFT)    & CC_SHN_MASK)
+#define NVME_CC_IOSQES(cc) ((cc >> CC_IOSQES_SHIFT) & CC_IOSQES_MASK)
+#define NVME_CC_IOCQES(cc) ((cc >> CC_IOCQES_SHIFT) & CC_IOCQES_MASK)
+
+enum NvmeCstsShift {
+    CSTS_RDY_SHIFT      = 0,
+    CSTS_CFS_SHIFT      = 1,
+    CSTS_SHST_SHIFT     = 2,
+    CSTS_NSSRO_SHIFT    = 4,
+};
+
+enum NvmeCstsMask {
+    CSTS_RDY_MASK   = 0x1,
+    CSTS_CFS_MASK   = 0x1,
+    CSTS_SHST_MASK  = 0x3,
+    CSTS_NSSRO_MASK = 0x1,
+};
+
+enum NvmeCsts {
+    NVME_CSTS_READY         = 1 << CSTS_RDY_SHIFT,
+    NVME_CSTS_FAILED        = 1 << CSTS_CFS_SHIFT,
+    NVME_CSTS_SHST_NORMAL   = 0 << CSTS_SHST_SHIFT,
+    NVME_CSTS_SHST_PROGRESS = 1 << CSTS_SHST_SHIFT,
+    NVME_CSTS_SHST_COMPLETE = 2 << CSTS_SHST_SHIFT,
+    NVME_CSTS_NSSRO         = 1 << CSTS_NSSRO_SHIFT,
+};
+
+#define NVME_CSTS_RDY(csts)     ((csts >> CSTS_RDY_SHIFT)   & CSTS_RDY_MASK)
+#define NVME_CSTS_CFS(csts)     ((csts >> CSTS_CFS_SHIFT)   & CSTS_CFS_MASK)
+#define NVME_CSTS_SHST(csts)    ((csts >> CSTS_SHST_SHIFT)  & CSTS_SHST_MASK)
+#define NVME_CSTS_NSSRO(csts)   ((csts >> CSTS_NSSRO_SHIFT) & CSTS_NSSRO_MASK)
+
+enum NvmeAqaShift {
+    AQA_ASQS_SHIFT  = 0,
+    AQA_ACQS_SHIFT  = 16,
+};
+
+enum NvmeAqaMask {
+    AQA_ASQS_MASK   = 0xfff,
+    AQA_ACQS_MASK   = 0xfff,
+};
+
+#define NVME_AQA_ASQS(aqa) ((aqa >> AQA_ASQS_SHIFT) & AQA_ASQS_MASK)
+#define NVME_AQA_ACQS(aqa) ((aqa >> AQA_ACQS_SHIFT) & AQA_ACQS_MASK)
+
+typedef struct NvmeCmd {
+    uint8_t     opcode;
+    uint8_t     fuse;
+    uint16_t    cid;
+    uint32_t    nsid;
+    uint64_t    res1;
+    uint64_t    mptr;
+    uint64_t    prp1;
+    uint64_t    prp2;
+    uint32_t    cdw10;
+    uint32_t    cdw11;
+    uint32_t    cdw12;
+    uint32_t    cdw13;
+    uint32_t    cdw14;
+    uint32_t    cdw15;
+} NvmeCmd;
+
+enum NvmeAdminCommands {
+    NVME_ADM_CMD_DELETE_SQ      = 0x00,
+    NVME_ADM_CMD_CREATE_SQ      = 0x01,
+    NVME_ADM_CMD_GET_LOG_PAGE   = 0x02,
+    NVME_ADM_CMD_DELETE_CQ      = 0x04,
+    NVME_ADM_CMD_CREATE_CQ      = 0x05,
+    NVME_ADM_CMD_IDENTIFY       = 0x06,
+    NVME_ADM_CMD_ABORT          = 0x08,
+    NVME_ADM_CMD_SET_FEATURES   = 0x09,
+    NVME_ADM_CMD_GET_FEATURES   = 0x0a,
+    NVME_ADM_CMD_ASYNC_EV_REQ   = 0x0c,
+    NVME_ADM_CMD_ACTIVATE_FW    = 0x10,
+    NVME_ADM_CMD_DOWNLOAD_FW    = 0x11,
+    NVME_ADM_CMD_FORMAT_NVM     = 0x80,
+    NVME_ADM_CMD_SECURITY_SEND  = 0x81,
+    NVME_ADM_CMD_SECURITY_RECV  = 0x82,
+};
+
+enum NvmeIoCommands {
+    NVME_CMD_FLUSH              = 0x00,
+    NVME_CMD_WRITE              = 0x01,
+    NVME_CMD_READ               = 0x02,
+    NVME_CMD_WRITE_UNCOR        = 0x04,
+    NVME_CMD_COMPARE            = 0x05,
+    NVME_CMD_DSM                = 0x09,
+};
+
+typedef struct NvmeDeleteQ {
+    uint8_t     opcode;
+    uint8_t     flags;
+    uint16_t    cid;
+    uint32_t    rsvd1[9];
+    uint16_t    qid;
+    uint16_t    rsvd10;
+    uint32_t    rsvd11[5];
+} NvmeDeleteQ;
+
+typedef struct NvmeCreateCq {
+    uint8_t     opcode;
+    uint8_t     flags;
+    uint16_t    cid;
+    uint32_t    rsvd1[5];
+    uint64_t    prp1;
+    uint64_t    rsvd8;
+    uint16_t    cqid;
+    uint16_t    qsize;
+    uint16_t    cq_flags;
+    uint16_t    irq_vector;
+    uint32_t    rsvd12[4];
+} NvmeCreateCq;
+
+#define NVME_CQ_FLAGS_PC(cq_flags)  (cq_flags & 0x1)
+#define NVME_CQ_FLAGS_IEN(cq_flags) ((cq_flags >> 1) & 0x1)
+
+typedef struct NvmeCreateSq {
+    uint8_t     opcode;
+    uint8_t     flags;
+    uint16_t    cid;
+    uint32_t    rsvd1[5];
+    uint64_t    prp1;
+    uint64_t    rsvd8;
+    uint16_t    sqid;
+    uint16_t    qsize;
+    uint16_t    sq_flags;
+    uint16_t    cqid;
+    uint32_t    rsvd12[4];
+} NvmeCreateSq;
+
+#define NVME_SQ_FLAGS_PC(sq_flags)      (sq_flags & 0x1)
+#define NVME_SQ_FLAGS_QPRIO(sq_flags)   ((sq_flags >> 1) & 0x3)
+
+enum NvmeQueueFlags {
+    NVME_Q_PC           = 1,
+    NVME_Q_PRIO_URGENT  = 0,
+    NVME_Q_PRIO_HIGH    = 1,
+    NVME_Q_PRIO_NORMAL  = 2,
+    NVME_Q_PRIO_LOW     = 3,
+};
+
+typedef struct NvmeIdentify {
+    uint8_t     opcode;
+    uint8_t     flags;
+    uint16_t    cid;
+    uint32_t    nsid;
+    uint64_t    rsvd2[2];
+    uint64_t    prp1;
+    uint64_t    prp2;
+    uint32_t    cns;
+    uint32_t    rsvd11[5];
+} NvmeIdentify;
+
+typedef struct NvmeRwCmd {
+    uint8_t     opcode;
+    uint8_t     flags;
+    uint16_t    cid;
+    uint32_t    nsid;
+    uint64_t    rsvd2;
+    uint64_t    mptr;
+    uint64_t    prp1;
+    uint64_t    prp2;
+    uint64_t    slba;
+    uint16_t    nlb;
+    uint16_t    control;
+    uint32_t    dsmgmt;
+    uint32_t    reftag;
+    uint16_t    apptag;
+    uint16_t    appmask;
+} NvmeRwCmd;
+
+enum {
+    NVME_RW_LR                  = 1 << 15,
+    NVME_RW_FUA                 = 1 << 14,
+    NVME_RW_DSM_FREQ_UNSPEC     = 0,
+    NVME_RW_DSM_FREQ_TYPICAL    = 1,
+    NVME_RW_DSM_FREQ_RARE       = 2,
+    NVME_RW_DSM_FREQ_READS      = 3,
+    NVME_RW_DSM_FREQ_WRITES     = 4,
+    NVME_RW_DSM_FREQ_RW         = 5,
+    NVME_RW_DSM_FREQ_ONCE       = 6,
+    NVME_RW_DSM_FREQ_PREFETCH   = 7,
+    NVME_RW_DSM_FREQ_TEMP       = 8,
+    NVME_RW_DSM_LATENCY_NONE    = 0 << 4,
+    NVME_RW_DSM_LATENCY_IDLE    = 1 << 4,
+    NVME_RW_DSM_LATENCY_NORM    = 2 << 4,
+    NVME_RW_DSM_LATENCY_LOW     = 3 << 4,
+    NVME_RW_DSM_SEQ_REQ         = 1 << 6,
+    NVME_RW_DSM_COMPRESSED      = 1 << 7,
+    NVME_RW_PRINFO_PRACT        = 1 << 13,
+    NVME_RW_PRINFO_PRCHK_GUARD  = 1 << 12,
+    NVME_RW_PRINFO_PRCHK_APP    = 1 << 11,
+    NVME_RW_PRINFO_PRCHK_REF    = 1 << 10,
+};
+
+typedef struct NvmeDsmCmd {
+    uint8_t     opcode;
+    uint8_t     flags;
+    uint16_t    cid;
+    uint32_t    nsid;
+    uint64_t    rsvd2[2];
+    uint64_t    prp1;
+    uint64_t    prp2;
+    uint32_t    nr;
+    uint32_t    attributes;
+    uint32_t    rsvd12[4];
+} NvmeDsmCmd;
+
+enum {
+    NVME_DSMGMT_IDR = 1 << 0,
+    NVME_DSMGMT_IDW = 1 << 1,
+    NVME_DSMGMT_AD  = 1 << 2,
+};
+
+typedef struct NvmeDsmRange {
+    uint32_t    cattr;
+    uint32_t    nlb;
+    uint64_t    slba;
+} NvmeDsmRange;
+
+enum NvmeAsyncEventRequest {
+    NVME_AER_TYPE_ERROR                     = 0,
+    NVME_AER_TYPE_SMART                     = 1,
+    NVME_AER_TYPE_IO_SPECIFIC               = 6,
+    NVME_AER_TYPE_VENDOR_SPECIFIC           = 7,
+    NVME_AER_INFO_ERR_INVALID_SQ            = 0,
+    NVME_AER_INFO_ERR_INVALID_DB            = 1,
+    NVME_AER_INFO_ERR_DIAG_FAIL             = 2,
+    NVME_AER_INFO_ERR_PERS_INTERNAL_ERR     = 3,
+    NVME_AER_INFO_ERR_TRANS_INTERNAL_ERR    = 4,
+    NVME_AER_INFO_ERR_FW_IMG_LOAD_ERR       = 5,
+    NVME_AER_INFO_SMART_RELIABILITY         = 0,
+    NVME_AER_INFO_SMART_TEMP_THRESH         = 1,
+    NVME_AER_INFO_SMART_SPARE_THRESH        = 2,
+};
+
+typedef struct NvmeAerResult {
+    uint8_t event_type;
+    uint8_t event_info;
+    uint8_t log_page;
+    uint8_t resv;
+} NvmeAerResult;
+
+typedef struct NvmeCqe {
+    uint32_t    result;
+    uint32_t    rsvd;
+    uint16_t    sq_head;
+    uint16_t    sq_id;
+    uint16_t    cid;
+    uint16_t    status;
+} NvmeCqe;
+
+enum NvmeStatusCodes {
+    NVME_SUCCESS                = 0x0000,
+    NVME_INVALID_OPCODE         = 0x0001,
+    NVME_INVALID_FIELD          = 0x0002,
+    NVME_CID_CONFLICT           = 0x0003,
+    NVME_DATA_TRAS_ERROR        = 0x0004,
+    NVME_POWER_LOSS_ABORT       = 0x0005,
+    NVME_INTERNAL_DEV_ERROR     = 0x0006,
+    NVME_CMD_ABORT_REQ          = 0x0007,
+    NVME_CMD_ABORT_SQ_DEL       = 0x0008,
+    NVME_CMD_ABORT_FAILED_FUSE  = 0x0009,
+    NVME_CMD_ABORT_MISSING_FUSE = 0x000a,
+    NVME_INVALID_NSID           = 0x000b,
+    NVME_CMD_SEQ_ERROR          = 0x000c,
+    NVME_LBA_RANGE              = 0x0080,
+    NVME_CAP_EXCEEDED           = 0x0081,
+    NVME_NS_NOT_READY           = 0x0082,
+    NVME_NS_RESV_CONFLICT       = 0x0083,
+    NVME_INVALID_CQID           = 0x0100,
+    NVME_INVALID_QID            = 0x0101,
+    NVME_MAX_QSIZE_EXCEEDED     = 0x0102,
+    NVME_ACL_EXCEEDED           = 0x0103,
+    NVME_RESERVED               = 0x0104,
+    NVME_AER_LIMIT_EXCEEDED     = 0x0105,
+    NVME_INVALID_FW_SLOT        = 0x0106,
+    NVME_INVALID_FW_IMAGE       = 0x0107,
+    NVME_INVALID_IRQ_VECTOR     = 0x0108,
+    NVME_INVALID_LOG_ID         = 0x0109,
+    NVME_INVALID_FORMAT         = 0x010a,
+    NVME_FW_REQ_RESET           = 0x010b,
+    NVME_INVALID_QUEUE_DEL      = 0x010c,
+    NVME_FID_NOT_SAVEABLE       = 0x010d,
+    NVME_FID_NOT_NSID_SPEC      = 0x010f,
+    NVME_FW_REQ_SUSYSTEM_RESET  = 0x0110,
+    NVME_CONFLICTING_ATTRS      = 0x0180,
+    NVME_INVALID_PROT_INFO      = 0x0181,
+    NVME_WRITE_TO_RO            = 0x0182,
+    NVME_WRITE_FAULT            = 0x0280,
+    NVME_UNRECOVERED_READ       = 0x0281,
+    NVME_E2E_GUARD_ERROR        = 0x0282,
+    NVME_E2E_APP_ERROR          = 0x0283,
+    NVME_E2E_REF_ERROR          = 0x0284,
+    NVME_CMP_FAILURE            = 0x0285,
+    NVME_ACCESS_DENIED          = 0x0286,
+    NVME_MORE                   = 0x2000,
+    NVME_DNR                    = 0x4000,
+    NVME_NO_COMPLETE            = 0xffff,
+};
+
+typedef struct NvmeFwSlotInfoLog {
+    uint8_t     afi;
+    uint8_t     reserved1[7];
+    uint8_t     frs1[8];
+    uint8_t     frs2[8];
+    uint8_t     frs3[8];
+    uint8_t     frs4[8];
+    uint8_t     frs5[8];
+    uint8_t     frs6[8];
+    uint8_t     frs7[8];
+    uint8_t     reserved2[448];
+} NvmeFwSlotInfoLog;
+
+typedef struct NvmeErrorLog {
+    uint64_t    error_count;
+    uint16_t    sqid;
+    uint16_t    cid;
+    uint16_t    status_field;
+    uint16_t    param_error_location;
+    uint64_t    lba;
+    uint32_t    nsid;
+    uint8_t     vs;
+    uint8_t     resv[35];
+} NvmeErrorLog;
+
+typedef struct NvmeSmartLog {
+    uint8_t     critical_warning;
+    uint8_t     temperature[2];
+    uint8_t     available_spare;
+    uint8_t     available_spare_threshold;
+    uint8_t     percentage_used;
+    uint8_t     reserved1[26];
+    uint64_t    data_units_read[2];
+    uint64_t    data_units_written[2];
+    uint64_t    host_read_commands[2];
+    uint64_t    host_write_commands[2];
+    uint64_t    controller_busy_time[2];
+    uint64_t    power_cycles[2];
+    uint64_t    power_on_hours[2];
+    uint64_t    unsafe_shutdowns[2];
+    uint64_t    media_errors[2];
+    uint64_t    number_of_error_log_entries[2];
+    uint8_t     reserved2[320];
+} NvmeSmartLog;
+
+enum NvmeSmartWarn {
+    NVME_SMART_SPARE                  = 1 << 0,
+    NVME_SMART_TEMPERATURE            = 1 << 1,
+    NVME_SMART_RELIABILITY            = 1 << 2,
+    NVME_SMART_MEDIA_READ_ONLY        = 1 << 3,
+    NVME_SMART_FAILED_VOLATILE_MEDIA  = 1 << 4,
+};
+
+enum LogIdentifier {
+    NVME_LOG_ERROR_INFO     = 0x01,
+    NVME_LOG_SMART_INFO     = 0x02,
+    NVME_LOG_FW_SLOT_INFO   = 0x03,
+};
+
+typedef struct NvmePSD {
+    uint16_t    mp;
+    uint16_t    reserved;
+    uint32_t    enlat;
+    uint32_t    exlat;
+    uint8_t     rrt;
+    uint8_t     rrl;
+    uint8_t     rwt;
+    uint8_t     rwl;
+    uint8_t     resv[16];
+} NvmePSD;
+
+typedef struct NvmeIdCtrl {
+    uint16_t    vid;
+    uint16_t    ssvid;
+    uint8_t     sn[20];
+    uint8_t     mn[40];
+    uint8_t     fr[8];
+    uint8_t     rab;
+    uint8_t     ieee[3];
+    uint8_t     cmic;
+    uint8_t     mdts;
+    uint8_t     rsvd255[178];
+    uint16_t    oacs;
+    uint8_t     acl;
+    uint8_t     aerl;
+    uint8_t     frmw;
+    uint8_t     lpa;
+    uint8_t     elpe;
+    uint8_t     npss;
+    uint8_t     rsvd511[248];
+    uint8_t     sqes;
+    uint8_t     cqes;
+    uint16_t    rsvd515;
+    uint32_t    nn;
+    uint16_t    oncs;
+    uint16_t    fuses;
+    uint8_t     fna;
+    uint8_t     vwc;
+    uint16_t    awun;
+    uint16_t    awupf;
+    uint8_t     rsvd703[174];
+    uint8_t     rsvd2047[1344];
+    NvmePSD     psd[32];
+    uint8_t     vs[1024];
+} NvmeIdCtrl;
+
+enum NvmeIdCtrlOacs {
+    NVME_OACS_SECURITY  = 1 << 0,
+    NVME_OACS_FORMAT    = 1 << 1,
+    NVME_OACS_FW        = 1 << 2,
+};
+
+enum NvmeIdCtrlOncs {
+    NVME_ONCS_COMPARE       = 1 << 0,
+    NVME_ONCS_WRITE_UNCORR  = 1 << 1,
+    NVME_ONCS_DSM           = 1 << 2,
+    NVME_ONCS_WRITE_ZEROS   = 1 << 3,
+    NVME_ONCS_FEATURES      = 1 << 4,
+    NVME_ONCS_RESRVATIONS   = 1 << 5,
+};
+
+#define NVME_CTRL_SQES_MIN(sqes) ((sqes) & 0xf)
+#define NVME_CTRL_SQES_MAX(sqes) (((sqes) >> 4) & 0xf)
+#define NVME_CTRL_CQES_MIN(cqes) ((cqes) & 0xf)
+#define NVME_CTRL_CQES_MAX(cqes) (((cqes) >> 4) & 0xf)
+
+typedef struct NvmeFeatureVal {
+    uint32_t    arbitration;
+    uint32_t    power_mgmt;
+    uint32_t    temp_thresh;
+    uint32_t    err_rec;
+    uint32_t    volatile_wc;
+    uint32_t    num_queues;
+    uint32_t    int_coalescing;
+    uint32_t    *int_vector_config;
+    uint32_t    write_atomicity;
+    uint32_t    async_config;
+    uint32_t    sw_prog_marker;
+} NvmeFeatureVal;
+
+#define NVME_ARB_AB(arb)    (arb & 0x7)
+#define NVME_ARB_LPW(arb)   ((arb >> 8) & 0xff)
+#define NVME_ARB_MPW(arb)   ((arb >> 16) & 0xff)
+#define NVME_ARB_HPW(arb)   ((arb >> 24) & 0xff)
+
+#define NVME_INTC_THR(intc)     (intc & 0xff)
+#define NVME_INTC_TIME(intc)    ((intc >> 8) & 0xff)
+
+enum NvmeFeatureIds {
+    NVME_ARBITRATION                = 0x1,
+    NVME_POWER_MANAGEMENT           = 0x2,
+    NVME_LBA_RANGE_TYPE             = 0x3,
+    NVME_TEMPERATURE_THRESHOLD      = 0x4,
+    NVME_ERROR_RECOVERY             = 0x5,
+    NVME_VOLATILE_WRITE_CACHE       = 0x6,
+    NVME_NUMBER_OF_QUEUES           = 0x7,
+    NVME_INTERRUPT_COALESCING       = 0x8,
+    NVME_INTERRUPT_VECTOR_CONF      = 0x9,
+    NVME_WRITE_ATOMICITY            = 0xa,
+    NVME_ASYNCHRONOUS_EVENT_CONF    = 0xb,
+    NVME_SOFTWARE_PROGRESS_MARKER   = 0x80
+};
+
+typedef struct NvmeRangeType {
+    uint8_t     type;
+    uint8_t     attributes;
+    uint8_t     rsvd2[14];
+    uint64_t    slba;
+    uint64_t    nlb;
+    uint8_t     guid[16];
+    uint8_t     rsvd48[16];
+} NvmeRangeType;
+
+typedef struct NvmeLBAF {
+    uint16_t    ms;
+    uint8_t     ds;
+    uint8_t     rp;
+} NvmeLBAF;
+
+typedef struct NvmeIdNs {
+    uint64_t    nsze;
+    uint64_t    ncap;
+    uint64_t    nuse;
+    uint8_t     nsfeat;
+    uint8_t     nlbaf;
+    uint8_t     flbas;
+    uint8_t     mc;
+    uint8_t     dpc;
+    uint8_t     dps;
+    uint8_t     res30[98];
+    NvmeLBAF    lbaf[16];
+    uint8_t     res192[192];
+    uint8_t     vs[3712];
+} NvmeIdNs;
+
+#define NVME_ID_NS_NSFEAT_THIN(nsfeat)      ((nsfeat & 0x1))
+#define NVME_ID_NS_FLBAS_EXTENDED(flbas)    ((flbas >> 4) & 0x1)
+#define NVME_ID_NS_FLBAS_INDEX(flbas)       ((flbas & 0xf))
+#define NVME_ID_NS_MC_SEPARATE(mc)          ((mc >> 1) & 0x1)
+#define NVME_ID_NS_MC_EXTENDED(mc)          ((mc & 0x1))
+#define NVME_ID_NS_DPC_LAST_EIGHT(dpc)      ((dpc >> 4) & 0x1)
+#define NVME_ID_NS_DPC_FIRST_EIGHT(dpc)     ((dpc >> 3) & 0x1)
+#define NVME_ID_NS_DPC_TYPE_3(dpc)          ((dpc >> 2) & 0x1)
+#define NVME_ID_NS_DPC_TYPE_2(dpc)          ((dpc >> 1) & 0x1)
+#define NVME_ID_NS_DPC_TYPE_1(dpc)          ((dpc & 0x1))
+
+enum NvmeIdNsDps {
+    DPS_TYPE_NONE   = 0,
+    DPS_TYPE_0      = 1,
+    DPS_TYPE_1      = 2,
+    DPS_TYPE_2      = 3,
+    DPS_TYPE_3      = 4,
+    DPS_TYPE_MASK   = 0x7,
+    DPS_FIRST_EIGHT = 8,
+};
+
+static inline void _nvme_check_size(void)
+{
+    QEMU_BUILD_BUG_ON(sizeof(NvmeAerResult) != 4);
+    QEMU_BUILD_BUG_ON(sizeof(NvmeCqe) != 16);
+    QEMU_BUILD_BUG_ON(sizeof(NvmeDsmRange) != 16);
+    QEMU_BUILD_BUG_ON(sizeof(NvmeCmd) != 64);
+    QEMU_BUILD_BUG_ON(sizeof(NvmeDeleteQ) != 64);
+    QEMU_BUILD_BUG_ON(sizeof(NvmeCreateCq) != 64);
+    QEMU_BUILD_BUG_ON(sizeof(NvmeCreateSq) != 64);
+    QEMU_BUILD_BUG_ON(sizeof(NvmeIdentify) != 64);
+    QEMU_BUILD_BUG_ON(sizeof(NvmeRwCmd) != 64);
+    QEMU_BUILD_BUG_ON(sizeof(NvmeDsmCmd) != 64);
+    QEMU_BUILD_BUG_ON(sizeof(NvmeRangeType) != 64);
+    QEMU_BUILD_BUG_ON(sizeof(NvmeErrorLog) != 64);
+    QEMU_BUILD_BUG_ON(sizeof(NvmeFwSlotInfoLog) != 512);
+    QEMU_BUILD_BUG_ON(sizeof(NvmeSmartLog) != 512);
+    QEMU_BUILD_BUG_ON(sizeof(NvmeIdCtrl) != 4096);
+    QEMU_BUILD_BUG_ON(sizeof(NvmeIdNs) != 4096);
+}
+
+typedef struct NvmeAsyncEvent {
+    QSIMPLEQ_ENTRY(NvmeAsyncEvent) entry;
+    NvmeAerResult result;
+} NvmeAsyncEvent;
+
+typedef struct NvmeRequest {
+    struct NvmeSQueue       *sq;
+    BlockDriverAIOCB        *aiocb;
+    uint16_t                status;
+    NvmeCqe                 cqe;
+    QEMUSGList              qsg;
+    QTAILQ_ENTRY(NvmeRequest)entry;
+} NvmeRequest;
+
+typedef struct NvmeSQueue {
+    struct NvmeCtrl *ctrl;
+    uint16_t    sqid;
+    uint16_t    cqid;
+    uint32_t    head;
+    uint32_t    tail;
+    uint32_t    size;
+    uint64_t    dma_addr;
+    QEMUTimer   *timer;
+    NvmeRequest *io_req;
+    QTAILQ_HEAD(sq_req_list, NvmeRequest) req_list;
+    QTAILQ_HEAD(out_req_list, NvmeRequest) out_req_list;
+    QTAILQ_ENTRY(NvmeSQueue) entry;
+} NvmeSQueue;
+
+typedef struct NvmeCQueue {
+    struct NvmeCtrl *ctrl;
+    uint8_t     phase;
+    uint16_t    cqid;
+    uint16_t    irq_enabled;
+    uint32_t    head;
+    uint32_t    tail;
+    uint32_t    vector;
+    uint32_t    size;
+    uint64_t    dma_addr;
+    QEMUTimer   *timer;
+    QTAILQ_HEAD(sq_list, NvmeSQueue) sq_list;
+    QTAILQ_HEAD(cq_req_list, NvmeRequest) req_list;
+} NvmeCQueue;
+
+typedef struct NvmeNamespace {
+    NvmeIdNs        id_ns;
+    NvmeRangeType   lba_range[64];
+    uint64_t        start_block;
+} NvmeNamespace;
+
+#define TYPE_NVME "nvme"
+#define NVME(obj) \
+        OBJECT_CHECK(NvmeCtrl, (obj), TYPE_NVME)
+
+typedef struct NvmeCtrl {
+    PCIDevice       parent_obj;
+
+    MemoryRegion iomem;
+    NvmeBar      bar;
+    BlockConf    conf;
+
+    int         instance;
+    uint16_t    page_size;
+    uint16_t    page_bits;
+    uint16_t    max_prp_ents;
+    uint16_t    cqe_size;
+    uint16_t    sqe_size;
+    uint32_t    reg_size;
+    uint32_t    num_namespaces;
+    uint32_t    ns_size;
+    uint32_t    num_queues;
+
+    char            *serial;
+    NvmeNamespace   *namespaces;
+    NvmeSQueue      **sq;
+    NvmeCQueue      **cq;
+    NvmeSQueue      admin_sq;
+    NvmeCQueue      admin_cq;
+    NvmeIdCtrl      id_ctrl;
+} NvmeCtrl;
+
+#endif /* HW_NVME_H */
diff --git a/hw/pci/pci_ids.h b/hw/pci/pci_ids.h
index d8dc2f1..08f8161 100644
--- a/hw/pci/pci_ids.h
+++ b/hw/pci/pci_ids.h
@@ -19,6 +19,7 @@ 
 #define PCI_CLASS_STORAGE_IDE            0x0101
 #define PCI_CLASS_STORAGE_RAID           0x0104
 #define PCI_CLASS_STORAGE_SATA           0x0106
+#define PCI_CLASS_STORAGE_EXPRESS        0x0108
 #define PCI_CLASS_STORAGE_OTHER          0x0180
 
 #define PCI_CLASS_NETWORK_ETHERNET       0x0200