diff options
Diffstat (limited to 'block/nvme.c')
| -rw-r--r-- | block/nvme.c | 1182 |
1 files changed, 1182 insertions, 0 deletions
diff --git a/block/nvme.c b/block/nvme.c new file mode 100644 index 0000000000..0bae185b88 --- /dev/null +++ b/block/nvme.c @@ -0,0 +1,1182 @@ +/* + * NVMe block driver based on vfio + * + * Copyright 2016 - 2018 Red Hat, Inc. + * + * Authors: + * Fam Zheng <famz@redhat.com> + * Paolo Bonzini <pbonzini@redhat.com> + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#include "qemu/osdep.h" +#include <linux/vfio.h> +#include "qapi/error.h" +#include "qapi/qmp/qdict.h" +#include "qapi/qmp/qstring.h" +#include "qemu/error-report.h" +#include "qemu/cutils.h" +#include "qemu/vfio-helpers.h" +#include "block/block_int.h" +#include "trace.h" + +/* TODO: Move nvme spec definitions from hw/block/nvme.h into a separate file + * that doesn't depend on dma/pci headers. */ +#include "sysemu/dma.h" +#include "hw/pci/pci.h" +#include "hw/block/block.h" +#include "hw/block/nvme.h" + +#define NVME_SQ_ENTRY_BYTES 64 +#define NVME_CQ_ENTRY_BYTES 16 +#define NVME_QUEUE_SIZE 128 +#define NVME_BAR_SIZE 8192 + +typedef struct { + int32_t head, tail; + uint8_t *queue; + uint64_t iova; + /* Hardware MMIO register */ + volatile uint32_t *doorbell; +} NVMeQueue; + +typedef struct { + BlockCompletionFunc *cb; + void *opaque; + int cid; + void *prp_list_page; + uint64_t prp_list_iova; + bool busy; +} NVMeRequest; + +typedef struct { + CoQueue free_req_queue; + QemuMutex lock; + + /* Fields protected by BQL */ + int index; + uint8_t *prp_list_pages; + + /* Fields protected by @lock */ + NVMeQueue sq, cq; + int cq_phase; + NVMeRequest reqs[NVME_QUEUE_SIZE]; + bool busy; + int need_kick; + int inflight; +} NVMeQueuePair; + +/* Memory mapped registers */ +typedef volatile struct { + uint64_t cap; + uint32_t vs; + uint32_t intms; + uint32_t intmc; + uint32_t cc; + uint32_t reserved0; + uint32_t csts; + uint32_t nssr; + uint32_t aqa; + uint64_t asq; + uint64_t acq; + uint32_t cmbloc; + uint32_t cmbsz; + uint8_t reserved1[0xec0]; + uint8_t cmd_set_specfic[0x100]; + uint32_t doorbells[]; +} QEMU_PACKED NVMeRegs; + +QEMU_BUILD_BUG_ON(offsetof(NVMeRegs, doorbells) != 0x1000); + +typedef struct { + AioContext *aio_context; + QEMUVFIOState *vfio; + NVMeRegs *regs; + /* The submission/completion queue pairs. + * [0]: admin queue. + * [1..]: io queues. + */ + NVMeQueuePair **queues; + int nr_queues; + size_t page_size; + /* How many uint32_t elements does each doorbell entry take. */ + size_t doorbell_scale; + bool write_cache_supported; + EventNotifier irq_notifier; + uint64_t nsze; /* Namespace size reported by identify command */ + int nsid; /* The namespace id to read/write data. */ + uint64_t max_transfer; + int plugged; + + CoMutex dma_map_lock; + CoQueue dma_flush_queue; + + /* Total size of mapped qiov, accessed under dma_map_lock */ + int dma_map_count; +} BDRVNVMeState; + +#define NVME_BLOCK_OPT_DEVICE "device" +#define NVME_BLOCK_OPT_NAMESPACE "namespace" + +static QemuOptsList runtime_opts = { + .name = "nvme", + .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head), + .desc = { + { + .name = NVME_BLOCK_OPT_DEVICE, + .type = QEMU_OPT_STRING, + .help = "NVMe PCI device address", + }, + { + .name = NVME_BLOCK_OPT_NAMESPACE, + .type = QEMU_OPT_NUMBER, + .help = "NVMe namespace", + }, + { /* end of list */ } + }, +}; + +static void nvme_init_queue(BlockDriverState *bs, NVMeQueue *q, + int nentries, int entry_bytes, Error **errp) +{ + BDRVNVMeState *s = bs->opaque; + size_t bytes; + int r; + + bytes = ROUND_UP(nentries * entry_bytes, s->page_size); + q->head = q->tail = 0; + q->queue = qemu_try_blockalign0(bs, bytes); + + if (!q->queue) { + error_setg(errp, "Cannot allocate queue"); + return; + } + r = qemu_vfio_dma_map(s->vfio, q->queue, bytes, false, &q->iova); + if (r) { + error_setg(errp, "Cannot map queue"); + } +} + +static void nvme_free_queue_pair(BlockDriverState *bs, NVMeQueuePair *q) +{ + qemu_vfree(q->prp_list_pages); + qemu_vfree(q->sq.queue); + qemu_vfree(q->cq.queue); + qemu_mutex_destroy(&q->lock); + g_free(q); +} + +static void nvme_free_req_queue_cb(void *opaque) +{ + NVMeQueuePair *q = opaque; + + qemu_mutex_lock(&q->lock); + while (qemu_co_enter_next(&q->free_req_queue, &q->lock)) { + /* Retry all pending requests */ + } + qemu_mutex_unlock(&q->lock); +} + +static NVMeQueuePair *nvme_create_queue_pair(BlockDriverState *bs, + int idx, int size, + Error **errp) +{ + int i, r; + BDRVNVMeState *s = bs->opaque; + Error *local_err = NULL; + NVMeQueuePair *q = g_new0(NVMeQueuePair, 1); + uint64_t prp_list_iova; + + qemu_mutex_init(&q->lock); + q->index = idx; + qemu_co_queue_init(&q->free_req_queue); + q->prp_list_pages = qemu_blockalign0(bs, s->page_size * NVME_QUEUE_SIZE); + r = qemu_vfio_dma_map(s->vfio, q->prp_list_pages, + s->page_size * NVME_QUEUE_SIZE, + false, &prp_list_iova); + if (r) { + goto fail; + } + for (i = 0; i < NVME_QUEUE_SIZE; i++) { + NVMeRequest *req = &q->reqs[i]; + req->cid = i + 1; + req->prp_list_page = q->prp_list_pages + i * s->page_size; + req->prp_list_iova = prp_list_iova + i * s->page_size; + } + nvme_init_queue(bs, &q->sq, size, NVME_SQ_ENTRY_BYTES, &local_err); + if (local_err) { + error_propagate(errp, local_err); + goto fail; + } + q->sq.doorbell = &s->regs->doorbells[idx * 2 * s->doorbell_scale]; + + nvme_init_queue(bs, &q->cq, size, NVME_CQ_ENTRY_BYTES, &local_err); + if (local_err) { + error_propagate(errp, local_err); + goto fail; + } + q->cq.doorbell = &s->regs->doorbells[idx * 2 * s->doorbell_scale + 1]; + + return q; +fail: + nvme_free_queue_pair(bs, q); + return NULL; +} + +/* With q->lock */ +static void nvme_kick(BDRVNVMeState *s, NVMeQueuePair *q) +{ + if (s->plugged || !q->need_kick) { + return; + } + trace_nvme_kick(s, q->index); + assert(!(q->sq.tail & 0xFF00)); + /* Fence the write to submission queue entry before notifying the device. */ + smp_wmb(); + *q->sq.doorbell = cpu_to_le32(q->sq.tail); + q->inflight += q->need_kick; + q->need_kick = 0; +} + +/* Find a free request element if any, otherwise: + * a) if in coroutine context, try to wait for one to become available; + * b) if not in coroutine, return NULL; + */ +static NVMeRequest *nvme_get_free_req(NVMeQueuePair *q) +{ + int i; + NVMeRequest *req = NULL; + + qemu_mutex_lock(&q->lock); + while (q->inflight + q->need_kick > NVME_QUEUE_SIZE - 2) { + /* We have to leave one slot empty as that is the full queue case (head + * == tail + 1). */ + if (qemu_in_coroutine()) { + trace_nvme_free_req_queue_wait(q); + qemu_co_queue_wait(&q->free_req_queue, &q->lock); + } else { + qemu_mutex_unlock(&q->lock); + return NULL; + } + } + for (i = 0; i < NVME_QUEUE_SIZE; i++) { + if (!q->reqs[i].busy) { + q->reqs[i].busy = true; + req = &q->reqs[i]; + break; + } + } + /* We have checked inflight and need_kick while holding q->lock, so one + * free req must be available. */ + assert(req); + qemu_mutex_unlock(&q->lock); + return req; +} + +static inline int nvme_translate_error(const NvmeCqe *c) +{ + uint16_t status = (le16_to_cpu(c->status) >> 1) & 0xFF; + if (status) { + trace_nvme_error(le32_to_cpu(c->result), + le16_to_cpu(c->sq_head), + le16_to_cpu(c->sq_id), + le16_to_cpu(c->cid), + le16_to_cpu(status)); + } + switch (status) { + case 0: + return 0; + case 1: + return -ENOSYS; + case 2: + return -EINVAL; + default: + return -EIO; + } +} + +/* With q->lock */ +static bool nvme_process_completion(BDRVNVMeState *s, NVMeQueuePair *q) +{ + bool progress = false; + NVMeRequest *preq; + NVMeRequest req; + NvmeCqe *c; + + trace_nvme_process_completion(s, q->index, q->inflight); + if (q->busy || s->plugged) { + trace_nvme_process_completion_queue_busy(s, q->index); + return false; + } + q->busy = true; + assert(q->inflight >= 0); + while (q->inflight) { + int16_t cid; + c = (NvmeCqe *)&q->cq.queue[q->cq.head * NVME_CQ_ENTRY_BYTES]; + if (!c->cid || (le16_to_cpu(c->status) & 0x1) == q->cq_phase) { + break; + } + q->cq.head = (q->cq.head + 1) % NVME_QUEUE_SIZE; + if (!q->cq.head) { + q->cq_phase = !q->cq_phase; + } + cid = le16_to_cpu(c->cid); + if (cid == 0 || cid > NVME_QUEUE_SIZE) { + fprintf(stderr, "Unexpected CID in completion queue: %" PRIu32 "\n", + cid); + continue; + } + assert(cid <= NVME_QUEUE_SIZE); + trace_nvme_complete_command(s, q->index, cid); + preq = &q->reqs[cid - 1]; + req = *preq; + assert(req.cid == cid); + assert(req.cb); + preq->busy = false; + preq->cb = preq->opaque = NULL; + qemu_mutex_unlock(&q->lock); + req.cb(req.opaque, nvme_translate_error(c)); + qemu_mutex_lock(&q->lock); + c->cid = cpu_to_le16(0); + q->inflight--; + /* Flip Phase Tag bit. */ + c->status = cpu_to_le16(le16_to_cpu(c->status) ^ 0x1); + progress = true; + } + if (progress) { + /* Notify the device so it can post more completions. */ + smp_mb_release(); + *q->cq.doorbell = cpu_to_le32(q->cq.head); + if (!qemu_co_queue_empty(&q->free_req_queue)) { + aio_bh_schedule_oneshot(s->aio_context, nvme_free_req_queue_cb, q); + } + } + q->busy = false; + return progress; +} + +static void nvme_trace_command(const NvmeCmd *cmd) +{ + int i; + + for (i = 0; i < 8; ++i) { + uint8_t *cmdp = (uint8_t *)cmd + i * 8; + trace_nvme_submit_command_raw(cmdp[0], cmdp[1], cmdp[2], cmdp[3], + cmdp[4], cmdp[5], cmdp[6], cmdp[7]); + } +} + +static void nvme_submit_command(BDRVNVMeState *s, NVMeQueuePair *q, + NVMeRequest *req, + NvmeCmd *cmd, BlockCompletionFunc cb, + void *opaque) +{ + assert(!req->cb); + req->cb = cb; + req->opaque = opaque; + cmd->cid = cpu_to_le32(req->cid); + + trace_nvme_submit_command(s, q->index, req->cid); + nvme_trace_command(cmd); + qemu_mutex_lock(&q->lock); + memcpy((uint8_t *)q->sq.queue + + q->sq.tail * NVME_SQ_ENTRY_BYTES, cmd, sizeof(*cmd)); + q->sq.tail = (q->sq.tail + 1) % NVME_QUEUE_SIZE; + q->need_kick++; + nvme_kick(s, q); + nvme_process_completion(s, q); + qemu_mutex_unlock(&q->lock); +} + +static void nvme_cmd_sync_cb(void *opaque, int ret) +{ + int *pret = opaque; + *pret = ret; +} + +static int nvme_cmd_sync(BlockDriverState *bs, NVMeQueuePair *q, + NvmeCmd *cmd) +{ + NVMeRequest *req; + BDRVNVMeState *s = bs->opaque; + int ret = -EINPROGRESS; + req = nvme_get_free_req(q); + if (!req) { + return -EBUSY; + } + nvme_submit_command(s, q, req, cmd, nvme_cmd_sync_cb, &ret); + + BDRV_POLL_WHILE(bs, ret == -EINPROGRESS); + return ret; +} + +static void nvme_identify(BlockDriverState *bs, int namespace, Error **errp) +{ + BDRVNVMeState *s = bs->opaque; + NvmeIdCtrl *idctrl; + NvmeIdNs *idns; + uint8_t *resp; + int r; + uint64_t iova; + NvmeCmd cmd = { + .opcode = NVME_ADM_CMD_IDENTIFY, + .cdw10 = cpu_to_le32(0x1), + }; + + resp = qemu_try_blockalign0(bs, sizeof(NvmeIdCtrl)); + if (!resp) { + error_setg(errp, "Cannot allocate buffer for identify response"); + goto out; + } + idctrl = (NvmeIdCtrl *)resp; + idns = (NvmeIdNs *)resp; + r = qemu_vfio_dma_map(s->vfio, resp, sizeof(NvmeIdCtrl), true, &iova); + if (r) { + error_setg(errp, "Cannot map buffer for DMA"); + goto out; + } + cmd.prp1 = cpu_to_le64(iova); + + if (nvme_cmd_sync(bs, s->queues[0], &cmd)) { + error_setg(errp, "Failed to identify controller"); + goto out; + } + + if (le32_to_cpu(idctrl->nn) < namespace) { + error_setg(errp, "Invalid namespace"); + goto out; + } + s->write_cache_supported = le32_to_cpu(idctrl->vwc) & 0x1; + s->max_transfer = (idctrl->mdts ? 1 << idctrl->mdts : 0) * s->page_size; + /* For now the page list buffer per command is one page, to hold at most + * s->page_size / sizeof(uint64_t) entries. */ + s->max_transfer = MIN_NON_ZERO(s->max_transfer, + s->page_size / sizeof(uint64_t) * s->page_size); + + memset(resp, 0, 4096); + + cmd.cdw10 = 0; + cmd.nsid = cpu_to_le32(namespace); + if (nvme_cmd_sync(bs, s->queues[0], &cmd)) { + error_setg(errp, "Failed to identify namespace"); + goto out; + } + + s->nsze = le64_to_cpu(idns->nsze); + +out: + qemu_vfio_dma_unmap(s->vfio, resp); + qemu_vfree(resp); +} + +static bool nvme_poll_queues(BDRVNVMeState *s) +{ + bool progress = false; + int i; + + for (i = 0; i < s->nr_queues; i++) { + NVMeQueuePair *q = s->queues[i]; + qemu_mutex_lock(&q->lock); + while (nvme_process_completion(s, q)) { + /* Keep polling */ + progress = true; + } + qemu_mutex_unlock(&q->lock); + } + return progress; +} + +static void nvme_handle_event(EventNotifier *n) +{ + BDRVNVMeState *s = container_of(n, BDRVNVMeState, irq_notifier); + + trace_nvme_handle_event(s); + aio_context_acquire(s->aio_context); + event_notifier_test_and_clear(n); + nvme_poll_queues(s); + aio_context_release(s->aio_context); +} + +static bool nvme_add_io_queue(BlockDriverState *bs, Error **errp) +{ + BDRVNVMeState *s = bs->opaque; + int n = s->nr_queues; + NVMeQueuePair *q; + NvmeCmd cmd; + int queue_size = NVME_QUEUE_SIZE; + + q = nvme_create_queue_pair(bs, n, queue_size, errp); + if (!q) { + return false; + } + cmd = (NvmeCmd) { + .opcode = NVME_ADM_CMD_CREATE_CQ, + .prp1 = cpu_to_le64(q->cq.iova), + .cdw10 = cpu_to_le32(((queue_size - 1) << 16) | (n & 0xFFFF)), + .cdw11 = cpu_to_le32(0x3), + }; + if (nvme_cmd_sync(bs, s->queues[0], &cmd)) { + error_setg(errp, "Failed to create io queue [%d]", n); + nvme_free_queue_pair(bs, q); + return false; + } + cmd = (NvmeCmd) { + .opcode = NVME_ADM_CMD_CREATE_SQ, + .prp1 = cpu_to_le64(q->sq.iova), + .cdw10 = cpu_to_le32(((queue_size - 1) << 16) | (n & 0xFFFF)), + .cdw11 = cpu_to_le32(0x1 | (n << 16)), + }; + if (nvme_cmd_sync(bs, s->queues[0], &cmd)) { + error_setg(errp, "Failed to create io queue [%d]", n); + nvme_free_queue_pair(bs, q); + return false; + } + s->queues = g_renew(NVMeQueuePair *, s->queues, n + 1); + s->queues[n] = q; + s->nr_queues++; + return true; +} + +static bool nvme_poll_cb(void *opaque) +{ + EventNotifier *e = opaque; + BDRVNVMeState *s = container_of(e, BDRVNVMeState, irq_notifier); + bool progress = false; + + trace_nvme_poll_cb(s); + progress = nvme_poll_queues(s); + return progress; +} + +static int nvme_init(BlockDriverState *bs, const char *device, int namespace, + Error **errp) +{ + BDRVNVMeState *s = bs->opaque; + int ret; + uint64_t cap; + uint64_t timeout_ms; + uint64_t deadline, now; + Error *local_err = NULL; + + qemu_co_mutex_init(&s->dma_map_lock); + qemu_co_queue_init(&s->dma_flush_queue); + s->nsid = namespace; + s->aio_context = bdrv_get_aio_context(bs); + ret = event_notifier_init(&s->irq_notifier, 0); + if (ret) { + error_setg(errp, "Failed to init event notifier"); + return ret; + } + + s->vfio = qemu_vfio_open_pci(device, errp); + if (!s->vfio) { + ret = -EINVAL; + goto fail; + } + + s->regs = qemu_vfio_pci_map_bar(s->vfio, 0, 0, NVME_BAR_SIZE, errp); + if (!s->regs) { + ret = -EINVAL; + goto fail; + } + + /* Perform initialize sequence as described in NVMe spec "7.6.1 + * Initialization". */ + + cap = le64_to_cpu(s->regs->cap); + if (!(cap & (1ULL << 37))) { + error_setg(errp, "Device doesn't support NVMe command set"); + ret = -EINVAL; + goto fail; + } + + s->page_size = MAX(4096, 1 << (12 + ((cap >> 48) & 0xF))); + s->doorbell_scale = (4 << (((cap >> 32) & 0xF))) / sizeof(uint32_t); + bs->bl.opt_mem_alignment = s->page_size; + timeout_ms = MIN(500 * ((cap >> 24) & 0xFF), 30000); + + /* Reset device to get a clean state. */ + s->regs->cc = cpu_to_le32(le32_to_cpu(s->regs->cc) & 0xFE); + /* Wait for CSTS.RDY = 0. */ + deadline = qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + timeout_ms * 1000000ULL; + while (le32_to_cpu(s->regs->csts) & 0x1) { + if (qemu_clock_get_ns(QEMU_CLOCK_REALTIME) > deadline) { + error_setg(errp, "Timeout while waiting for device to reset (%" + PRId64 " ms)", + timeout_ms); + ret = -ETIMEDOUT; + goto fail; + } + } + + /* Set up admin queue. */ + s->queues = g_new(NVMeQueuePair *, 1); + s->nr_queues = 1; + s->queues[0] = nvme_create_queue_pair(bs, 0, NVME_QUEUE_SIZE, errp); + if (!s->queues[0]) { + ret = -EINVAL; + goto fail; + } + QEMU_BUILD_BUG_ON(NVME_QUEUE_SIZE & 0xF000); + s->regs->aqa = cpu_to_le32((NVME_QUEUE_SIZE << 16) | NVME_QUEUE_SIZE); + s->regs->asq = cpu_to_le64(s->queues[0]->sq.iova); + s->regs->acq = cpu_to_le64(s->queues[0]->cq.iova); + + /* After setting up all control registers we can enable device now. */ + s->regs->cc = cpu_to_le32((ctz32(NVME_CQ_ENTRY_BYTES) << 20) | + (ctz32(NVME_SQ_ENTRY_BYTES) << 16) | + 0x1); + /* Wait for CSTS.RDY = 1. */ + now = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); + deadline = now + timeout_ms * 1000000; + while (!(le32_to_cpu(s->regs->csts) & 0x1)) { + if (qemu_clock_get_ns(QEMU_CLOCK_REALTIME) > deadline) { + error_setg(errp, "Timeout while waiting for device to start (%" + PRId64 " ms)", + timeout_ms); + ret = -ETIMEDOUT; + goto fail_queue; + } + } + + ret = qemu_vfio_pci_init_irq(s->vfio, &s->irq_notifier, + VFIO_PCI_MSIX_IRQ_INDEX, errp); + if (ret) { + goto fail_queue; + } + aio_set_event_notifier(bdrv_get_aio_context(bs), &s->irq_notifier, + false, nvme_handle_event, nvme_poll_cb); + + nvme_identify(bs, namespace, errp); + if (local_err) { + error_propagate(errp, local_err); + ret = -EIO; + goto fail_handler; + } + + /* Set up command queues. */ + if (!nvme_add_io_queue(bs, errp)) { + ret = -EIO; + goto fail_handler; + } + return 0; + +fail_handler: + aio_set_event_notifier(bdrv_get_aio_context(bs), &s->irq_notifier, + false, NULL, NULL); +fail_queue: + nvme_free_queue_pair(bs, s->queues[0]); +fail: + g_free(s->queues); + qemu_vfio_pci_unmap_bar(s->vfio, 0, (void *)s->regs, 0, NVME_BAR_SIZE); + qemu_vfio_close(s->vfio); + event_notifier_cleanup(&s->irq_notifier); + return ret; +} + +/* Parse a filename in the format of nvme://XXXX:XX:XX.X/X. Example: + * + * nvme://0000:44:00.0/1 + * + * where the "nvme://" is a fixed form of the protocol prefix, the middle part + * is the PCI address, and the last part is the namespace number starting from + * 1 according to the NVMe spec. */ +static void nvme_parse_filename(const char *filename, QDict *options, + Error **errp) +{ + int pref = strlen("nvme://"); + + if (strlen(filename) > pref && !strncmp(filename, "nvme://", pref)) { + const char *tmp = filename + pref; + char *device; + const char *namespace; + unsigned long ns; + const char *slash = strchr(tmp, '/'); + if (!slash) { + qdict_put(options, NVME_BLOCK_OPT_DEVICE, + qstring_from_str(tmp)); + return; + } + device = g_strndup(tmp, slash - tmp); + qdict_put(options, NVME_BLOCK_OPT_DEVICE, qstring_from_str(device)); + g_free(device); + namespace = slash + 1; + if (*namespace && qemu_strtoul(namespace, NULL, 10, &ns)) { + error_setg(errp, "Invalid namespace '%s', positive number expected", + namespace); + return; + } + qdict_put(options, NVME_BLOCK_OPT_NAMESPACE, + qstring_from_str(*namespace ? namespace : "1")); + } +} + +static int nvme_enable_disable_write_cache(BlockDriverState *bs, bool enable, + Error **errp) +{ + int ret; + BDRVNVMeState *s = bs->opaque; + NvmeCmd cmd = { + .opcode = NVME_ADM_CMD_SET_FEATURES, + .nsid = cpu_to_le32(s->nsid), + .cdw10 = cpu_to_le32(0x06), + .cdw11 = cpu_to_le32(enable ? 0x01 : 0x00), + }; + + ret = nvme_cmd_sync(bs, s->queues[0], &cmd); + if (ret) { + error_setg(errp, "Failed to configure NVMe write cache"); + } + return ret; +} + +static void nvme_close(BlockDriverState *bs) +{ + int i; + BDRVNVMeState *s = bs->opaque; + + for (i = 0; i < s->nr_queues; ++i) { + nvme_free_queue_pair(bs, s->queues[i]); + } + aio_set_event_notifier(bdrv_get_aio_context(bs), &s->irq_notifier, + false, NULL, NULL); + qemu_vfio_pci_unmap_bar(s->vfio, 0, (void *)s->regs, 0, NVME_BAR_SIZE); + qemu_vfio_close(s->vfio); +} + +static int nvme_file_open(BlockDriverState *bs, QDict *options, int flags, + Error **errp) +{ + const char *device; + QemuOpts *opts; + int namespace; + int ret; + BDRVNVMeState *s = bs->opaque; + + opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort); + qemu_opts_absorb_qdict(opts, options, &error_abort); + device = qemu_opt_get(opts, NVME_BLOCK_OPT_DEVICE); + if (!device) { + error_setg(errp, "'" NVME_BLOCK_OPT_DEVICE "' option is required"); + qemu_opts_del(opts); + return -EINVAL; + } + + namespace = qemu_opt_get_number(opts, NVME_BLOCK_OPT_NAMESPACE, 1); + ret = nvme_init(bs, device, namespace, errp); + qemu_opts_del(opts); + if (ret) { + goto fail; + } + if (flags & BDRV_O_NOCACHE) { + if (!s->write_cache_supported) { + error_setg(errp, + "NVMe controller doesn't support write cache configuration"); + ret = -EINVAL; + } else { + ret = nvme_enable_disable_write_cache(bs, !(flags & BDRV_O_NOCACHE), + errp); + } + if (ret) { + goto fail; + } + } + bs->supported_write_flags = BDRV_REQ_FUA; + return 0; +fail: + nvme_close(bs); + return ret; +} + +static int64_t nvme_getlength(BlockDriverState *bs) +{ + BDRVNVMeState *s = bs->opaque; + + return s->nsze << BDRV_SECTOR_BITS; +} + +/* Called with s->dma_map_lock */ +static coroutine_fn int nvme_cmd_unmap_qiov(BlockDriverState *bs, + QEMUIOVector *qiov) +{ + int r = 0; + BDRVNVMeState *s = bs->opaque; + + s->dma_map_count -= qiov->size; + if (!s->dma_map_count && !qemu_co_queue_empty(&s->dma_flush_queue)) { + r = qemu_vfio_dma_reset_temporary(s->vfio); + if (!r) { + qemu_co_queue_restart_all(&s->dma_flush_queue); + } + } + return r; +} + +/* Called with s->dma_map_lock */ +static coroutine_fn int nvme_cmd_map_qiov(BlockDriverState *bs, NvmeCmd *cmd, + NVMeRequest *req, QEMUIOVector *qiov) +{ + BDRVNVMeState *s = bs->opaque; + uint64_t *pagelist = req->prp_list_page; + int i, j, r; + int entries = 0; + + assert(qiov->size); + assert(QEMU_IS_ALIGNED(qiov->size, s->page_size)); + assert(qiov->size / s->page_size <= s->page_size / sizeof(uint64_t)); + for (i = 0; i < qiov->niov; ++i) { + bool retry = true; + uint64_t iova; +try_map: + r = qemu_vfio_dma_map(s->vfio, + qiov->iov[i].iov_base, + qiov->iov[i].iov_len, + true, &iova); + if (r == -ENOMEM && retry) { + retry = false; + trace_nvme_dma_flush_queue_wait(s); + if (s->dma_map_count) { + trace_nvme_dma_map_flush(s); + qemu_co_queue_wait(&s->dma_flush_queue, &s->dma_map_lock); + } else { + r = qemu_vfio_dma_reset_temporary(s->vfio); + if (r) { + goto fail; + } + } + goto try_map; + } + if (r) { + goto fail; + } + + for (j = 0; j < qiov->iov[i].iov_len / s->page_size; j++) { + pagelist[entries++] = iova + j * s->page_size; + } + trace_nvme_cmd_map_qiov_iov(s, i, qiov->iov[i].iov_base, + qiov->iov[i].iov_len / s->page_size); + } + + s->dma_map_count += qiov->size; + + assert(entries <= s->page_size / sizeof(uint64_t)); + switch (entries) { + case 0: + abort(); + case 1: + cmd->prp1 = cpu_to_le64(pagelist[0]); + cmd->prp2 = 0; + break; + case 2: + cmd->prp1 = cpu_to_le64(pagelist[0]); + cmd->prp2 = cpu_to_le64(pagelist[1]);; + break; + default: + cmd->prp1 = cpu_to_le64(pagelist[0]); + cmd->prp2 = cpu_to_le64(req->prp_list_iova); + for (i = 0; i < entries - 1; ++i) { + pagelist[i] = cpu_to_le64(pagelist[i + 1]); + } + pagelist[entries - 1] = 0; + break; + } + trace_nvme_cmd_map_qiov(s, cmd, req, qiov, entries); + for (i = 0; i < entries; ++i) { + trace_nvme_cmd_map_qiov_pages(s, i, pagelist[i]); + } + return 0; +fail: + /* No need to unmap [0 - i) iovs even if we've failed, since we don't + * increment s->dma_map_count. This is okay for fixed mapping memory areas + * because they are already mapped before calling this function; for + * temporary mappings, a later nvme_cmd_(un)map_qiov will reclaim by + * calling qemu_vfio_dma_reset_temporary when necessary. */ + return r; +} + +typedef struct { + Coroutine *co; + int ret; + AioContext *ctx; +} NVMeCoData; + +static void nvme_rw_cb_bh(void *opaque) +{ + NVMeCoData *data = opaque; + qemu_coroutine_enter(data->co); +} + +static void nvme_rw_cb(void *opaque, int ret) +{ + NVMeCoData *data = opaque; + data->ret = ret; + if (!data->co) { + /* The rw coroutine hasn't yielded, don't try to enter. */ + return; + } + aio_bh_schedule_oneshot(data->ctx, nvme_rw_cb_bh, data); +} + +static coroutine_fn int nvme_co_prw_aligned(BlockDriverState *bs, + uint64_t offset, uint64_t bytes, + QEMUIOVector *qiov, + bool is_write, + int flags) +{ + int r; + BDRVNVMeState *s = bs->opaque; + NVMeQueuePair *ioq = s->queues[1]; + NVMeRequest *req; + uint32_t cdw12 = (((bytes >> BDRV_SECTOR_BITS) - 1) & 0xFFFF) | + (flags & BDRV_REQ_FUA ? 1 << 30 : 0); + NvmeCmd cmd = { + .opcode = is_write ? NVME_CMD_WRITE : NVME_CMD_READ, + .nsid = cpu_to_le32(s->nsid), + .cdw10 = cpu_to_le32((offset >> BDRV_SECTOR_BITS) & 0xFFFFFFFF), + .cdw11 = cpu_to_le32(((offset >> BDRV_SECTOR_BITS) >> 32) & 0xFFFFFFFF), + .cdw12 = cpu_to_le32(cdw12), + }; + NVMeCoData data = { + .ctx = bdrv_get_aio_context(bs), + .ret = -EINPROGRESS, + }; + + trace_nvme_prw_aligned(s, is_write, offset, bytes, flags, qiov->niov); + assert(s->nr_queues > 1); + req = nvme_get_free_req(ioq); + assert(req); + + qemu_co_mutex_lock(&s->dma_map_lock); + r = nvme_cmd_map_qiov(bs, &cmd, req, qiov); + qemu_co_mutex_unlock(&s->dma_map_lock); + if (r) { + req->busy = false; + return r; + } + nvme_submit_command(s, ioq, req, &cmd, nvme_rw_cb, &data); + + data.co = qemu_coroutine_self(); + while (data.ret == -EINPROGRESS) { + qemu_coroutine_yield(); + } + + qemu_co_mutex_lock(&s->dma_map_lock); + r = nvme_cmd_unmap_qiov(bs, qiov); + qemu_co_mutex_unlock(&s->dma_map_lock); + if (r) { + return r; + } + + trace_nvme_rw_done(s, is_write, offset, bytes, data.ret); + return data.ret; +} + +static inline bool nvme_qiov_aligned(BlockDriverState *bs, + const QEMUIOVector *qiov) +{ + int i; + BDRVNVMeState *s = bs->opaque; + + for (i = 0; i < qiov->niov; ++i) { + if (!QEMU_PTR_IS_ALIGNED(qiov->iov[i].iov_base, s->page_size) || + !QEMU_IS_ALIGNED(qiov->iov[i].iov_len, s->page_size)) { + trace_nvme_qiov_unaligned(qiov, i, qiov->iov[i].iov_base, + qiov->iov[i].iov_len, s->page_size); + return false; + } + } + return true; +} + +static int nvme_co_prw(BlockDriverState *bs, uint64_t offset, uint64_t bytes, + QEMUIOVector *qiov, bool is_write, int flags) +{ + BDRVNVMeState *s = bs->opaque; + int r; + uint8_t *buf = NULL; + QEMUIOVector local_qiov; + + assert(QEMU_IS_ALIGNED(offset, s->page_size)); + assert(QEMU_IS_ALIGNED(bytes, s->page_size)); + assert(bytes <= s->max_transfer); + if (nvme_qiov_aligned(bs, qiov)) { + return nvme_co_prw_aligned(bs, offset, bytes, qiov, is_write, flags); + } + trace_nvme_prw_buffered(s, offset, bytes, qiov->niov, is_write); + buf = qemu_try_blockalign(bs, bytes); + + if (!buf) { + return -ENOMEM; + } + qemu_iovec_init(&local_qiov, 1); + if (is_write) { + qemu_iovec_to_buf(qiov, 0, buf, bytes); + } + qemu_iovec_add(&local_qiov, buf, bytes); + r = nvme_co_prw_aligned(bs, offset, bytes, &local_qiov, is_write, flags); + qemu_iovec_destroy(&local_qiov); + if (!r && !is_write) { + qemu_iovec_from_buf(qiov, 0, buf, bytes); + } + qemu_vfree(buf); + return r; +} + +static coroutine_fn int nvme_co_preadv(BlockDriverState *bs, + uint64_t offset, uint64_t bytes, + QEMUIOVector *qiov, int flags) +{ + return nvme_co_prw(bs, offset, bytes, qiov, false, flags); +} + +static coroutine_fn int nvme_co_pwritev(BlockDriverState *bs, + uint64_t offset, uint64_t bytes, + QEMUIOVector *qiov, int flags) +{ + return nvme_co_prw(bs, offset, bytes, qiov, true, flags); +} + +static coroutine_fn int nvme_co_flush(BlockDriverState *bs) +{ + BDRVNVMeState *s = bs->opaque; + NVMeQueuePair *ioq = s->queues[1]; + NVMeRequest *req; + NvmeCmd cmd = { + .opcode = NVME_CMD_FLUSH, + .nsid = cpu_to_le32(s->nsid), + }; + NVMeCoData data = { + .ctx = bdrv_get_aio_context(bs), + .ret = -EINPROGRESS, + }; + + assert(s->nr_queues > 1); + req = nvme_get_free_req(ioq); + assert(req); + nvme_submit_command(s, ioq, req, &cmd, nvme_rw_cb, &data); + + data.co = qemu_coroutine_self(); + if (data.ret == -EINPROGRESS) { + qemu_coroutine_yield(); + } + + return data.ret; +} + + +static int nvme_reopen_prepare(BDRVReopenState *reopen_state, + BlockReopenQueue *queue, Error **errp) +{ + return 0; +} + +static int64_t coroutine_fn nvme_co_get_block_status(BlockDriverState *bs, + int64_t sector_num, + int nb_sectors, int *pnum, + BlockDriverState **file) +{ + *pnum = nb_sectors; + *file = bs; + + return BDRV_BLOCK_ALLOCATED | BDRV_BLOCK_OFFSET_VALID | + (sector_num << BDRV_SECTOR_BITS); +} + +static void nvme_refresh_filename(BlockDriverState *bs, QDict *opts) +{ + QINCREF(opts); + qdict_del(opts, "filename"); + + if (!qdict_size(opts)) { + snprintf(bs->exact_filename, sizeof(bs->exact_filename), "%s://", + bs->drv->format_name); + } + + qdict_put(opts, "driver", qstring_from_str(bs->drv->format_name)); + bs->full_open_options = opts; +} + +static void nvme_refresh_limits(BlockDriverState *bs, Error **errp) +{ + BDRVNVMeState *s = bs->opaque; + + bs->bl.opt_mem_alignment = s->page_size; + bs->bl.request_alignment = s->page_size; + bs->bl.max_transfer = s->max_transfer; +} + +static void nvme_detach_aio_context(BlockDriverState *bs) +{ + BDRVNVMeState *s = bs->opaque; + + aio_set_event_notifier(bdrv_get_aio_context(bs), &s->irq_notifier, + false, NULL, NULL); +} + +static void nvme_attach_aio_context(BlockDriverState *bs, + AioContext *new_context) +{ + BDRVNVMeState *s = bs->opaque; + + s->aio_context = new_context; + aio_set_event_notifier(new_context, &s->irq_notifier, + false, nvme_handle_event, nvme_poll_cb); +} + +static void nvme_aio_plug(BlockDriverState *bs) +{ + BDRVNVMeState *s = bs->opaque; + s->plugged++; +} + +static void nvme_aio_unplug(BlockDriverState *bs) +{ + int i; + BDRVNVMeState *s = bs->opaque; + assert(s->plugged); + if (!--s->plugged) { + for (i = 1; i < s->nr_queues; i++) { + NVMeQueuePair *q = s->queues[i]; + qemu_mutex_lock(&q->lock); + nvme_kick(s, q); + nvme_process_completion(s, q); + qemu_mutex_unlock(&q->lock); + } + } +} + +static BlockDriver bdrv_nvme = { + .format_name = "nvme", + .protocol_name = "nvme", + .instance_size = sizeof(BDRVNVMeState), + + .bdrv_parse_filename = nvme_parse_filename, + .bdrv_file_open = nvme_file_open, + .bdrv_close = nvme_close, + .bdrv_getlength = nvme_getlength, + + .bdrv_co_preadv = nvme_co_preadv, + .bdrv_co_pwritev = nvme_co_pwritev, + .bdrv_co_flush_to_disk = nvme_co_flush, + .bdrv_reopen_prepare = nvme_reopen_prepare, + + .bdrv_co_get_block_status = nvme_co_get_block_status, + + .bdrv_refresh_filename = nvme_refresh_filename, + .bdrv_refresh_limits = nvme_refresh_limits, + + .bdrv_detach_aio_context = nvme_detach_aio_context, + .bdrv_attach_aio_context = nvme_attach_aio_context, + + .bdrv_io_plug = nvme_aio_plug, + .bdrv_io_unplug = nvme_aio_unplug, +}; + +static void bdrv_nvme_init(void) +{ + bdrv_register(&bdrv_nvme); +} + +block_init(bdrv_nvme_init); |