/* * NVMe block driver based on vfio * * Copyright 2016 - 2018 Red Hat, Inc. * * Authors: * Fam Zheng * Paolo Bonzini * * 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 #include "qapi/error.h" #include "qapi/qmp/qdict.h" #include "qapi/qmp/qstring.h" #include "qemu/error-report.h" #include "qemu/main-loop.h" #include "qemu/module.h" #include "qemu/cutils.h" #include "qemu/option.h" #include "qemu/vfio-helpers.h" #include "block/block_int.h" #include "sysemu/replay.h" #include "trace.h" #include "block/nvme.h" #define NVME_SQ_ENTRY_BYTES 64 #define NVME_CQ_ENTRY_BYTES 16 #define NVME_QUEUE_SIZE 128 #define NVME_DOORBELL_SIZE 4096 /* * We have to leave one slot empty as that is the full queue case where * head == tail + 1. */ #define NVME_NUM_REQS (NVME_QUEUE_SIZE - 1) typedef struct BDRVNVMeState BDRVNVMeState; /* Same index is used for queues and IRQs */ #define INDEX_ADMIN 0 #define INDEX_IO(n) (1 + n) /* This driver shares a single MSIX IRQ for the admin and I/O queues */ enum { MSIX_SHARED_IRQ_IDX = 0, MSIX_IRQ_COUNT = 1 }; 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; int free_req_next; /* q->reqs[] index of next free req */ } NVMeRequest; typedef struct { QemuMutex lock; /* Read from I/O code path, initialized under BQL */ BDRVNVMeState *s; int index; /* Fields protected by BQL */ uint8_t *prp_list_pages; /* Fields protected by @lock */ CoQueue free_req_queue; NVMeQueue sq, cq; int cq_phase; int free_req_head; NVMeRequest reqs[NVME_NUM_REQS]; int need_kick; int inflight; /* Thread-safe, no lock necessary */ QEMUBH *completion_bh; } NVMeQueuePair; struct BDRVNVMeState { AioContext *aio_context; QEMUVFIOState *vfio; /* Memory mapped registers */ volatile struct { uint32_t sq_tail; uint32_t cq_head; } *doorbells; /* The submission/completion queue pairs. * [0]: admin queue. * [1..]: io queues. */ NVMeQueuePair **queues; unsigned queue_count; 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[MSIX_IRQ_COUNT]; uint64_t nsze; /* Namespace size reported by identify command */ int nsid; /* The namespace id to read/write data. */ int blkshift; uint64_t max_transfer; bool plugged; bool supports_write_zeroes; bool supports_discard; CoMutex dma_map_lock; CoQueue dma_flush_queue; /* Total size of mapped qiov, accessed under dma_map_lock */ int dma_map_count; /* PCI address (required for nvme_refresh_filename()) */ char *device; struct { uint64_t completion_errors; uint64_t aligned_accesses; uint64_t unaligned_accesses; } stats; }; #define NVME_BLOCK_OPT_DEVICE "device" #define NVME_BLOCK_OPT_NAMESPACE "namespace" static void nvme_process_completion_bh(void *opaque); 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 */ } }, }; /* Returns true on success, false on failure. */ static bool nvme_init_queue(BDRVNVMeState *s, NVMeQueue *q, unsigned nentries, size_t entry_bytes, Error **errp) { size_t bytes; int r; bytes = ROUND_UP(nentries * entry_bytes, qemu_real_host_page_size); q->head = q->tail = 0; q->queue = qemu_try_memalign(qemu_real_host_page_size, bytes); if (!q->queue) { error_setg(errp, "Cannot allocate queue"); return false; } memset(q->queue, 0, bytes); r = qemu_vfio_dma_map(s->vfio, q->queue, bytes, false, &q->iova); if (r) { error_setg(errp, "Cannot map queue"); return false; } return true; } static void nvme_free_queue_pair(NVMeQueuePair *q) { trace_nvme_free_queue_pair(q->index, q); if (q->completion_bh) { qemu_bh_delete(q->completion_bh); } 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(BDRVNVMeState *s, AioContext *aio_context, unsigned idx, size_t size, Error **errp) { int i, r; NVMeQueuePair *q; uint64_t prp_list_iova; size_t bytes; q = g_try_new0(NVMeQueuePair, 1); if (!q) { return NULL; } trace_nvme_create_queue_pair(idx, q, size, aio_context, event_notifier_get_fd(s->irq_notifier)); bytes = QEMU_ALIGN_UP(s->page_size * NVME_NUM_REQS, qemu_real_host_page_size); q->prp_list_pages = qemu_try_memalign(qemu_real_host_page_size, bytes); if (!q->prp_list_pages) { goto fail; } memset(q->prp_list_pages, 0, bytes); qemu_mutex_init(&q->lock); q->s = s; q->index = idx; qemu_co_queue_init(&q->free_req_queue); q->completion_bh = aio_bh_new(aio_context, nvme_process_completion_bh, q); r = qemu_vfio_dma_map(s->vfio, q->prp_list_pages, bytes, false, &prp_list_iova); if (r) { goto fail; } q->free_req_head = -1; for (i = 0; i < NVME_NUM_REQS; i++) { NVMeRequest *req = &q->reqs[i]; req->cid = i + 1; req->free_req_next = q->free_req_head; q->free_req_head = i; req->prp_list_page = q->prp_list_pages + i * s->page_size; req->prp_list_iova = prp_list_iova + i * s->page_size; } if (!nvme_init_queue(s, &q->sq, size, NVME_SQ_ENTRY_BYTES, errp)) { goto fail; } q->sq.doorbell = &s->doorbells[idx * s->doorbell_scale].sq_tail; if (!nvme_init_queue(s, &q->cq, size, NVME_CQ_ENTRY_BYTES, errp)) { goto fail; } q->cq.doorbell = &s->doorbells[idx * s->doorbell_scale].cq_head; return q; fail: nvme_free_queue_pair(q); return NULL; } /* With q->lock */ static void nvme_kick(NVMeQueuePair *q) { BDRVNVMeState *s = q->s; 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) { NVMeRequest *req; qemu_mutex_lock(&q->lock); while (q->free_req_head == -1) { if (qemu_in_coroutine()) { trace_nvme_free_req_queue_wait(q->s, q->index); qemu_co_queue_wait(&q->free_req_queue, &q->lock); } else { qemu_mutex_unlock(&q->lock); return NULL; } } req = &q->reqs[q->free_req_head]; q->free_req_head = req->free_req_next; req->free_req_next = -1; qemu_mutex_unlock(&q->lock); return req; } /* With q->lock */ static void nvme_put_free_req_locked(NVMeQueuePair *q, NVMeRequest *req) { req->free_req_next = q->free_req_head; q->free_req_head = req - q->reqs; } /* With q->lock */ static void nvme_wake_free_req_locked(NVMeQueuePair *q) { if (!qemu_co_queue_empty(&q->free_req_queue)) { replay_bh_schedule_oneshot_event(q->s->aio_context, nvme_free_req_queue_cb, q); } } /* Insert a request in the freelist and wake waiters */ static void nvme_put_free_req_and_wake(NVMeQueuePair *q, NVMeRequest *req) { qemu_mutex_lock(&q->lock); nvme_put_free_req_locked(q, req); nvme_wake_free_req_locked(q); qemu_mutex_unlock(&q->lock); } 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(NVMeQueuePair *q) { BDRVNVMeState *s = q->s; bool progress = false; NVMeRequest *preq; NVMeRequest req; NvmeCqe *c; trace_nvme_process_completion(s, q->index, q->inflight); if (s->plugged) { trace_nvme_process_completion_queue_plugged(s, q->index); return false; } /* * Support re-entrancy when a request cb() function invokes aio_poll(). * Pending completions must be visible to aio_poll() so that a cb() * function can wait for the completion of another request. * * The aio_poll() loop will execute our BH and we'll resume completion * processing there. */ qemu_bh_schedule(q->completion_bh); assert(q->inflight >= 0); while (q->inflight) { int ret; int16_t cid; c = (NvmeCqe *)&q->cq.queue[q->cq.head * NVME_CQ_ENTRY_BYTES]; if ((le16_to_cpu(c->status) & 0x1) == q->cq_phase) { break; } ret = nvme_translate_error(c); if (ret) { s->stats.completion_errors++; } 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) { warn_report("NVMe: Unexpected CID in completion queue: %"PRIu32", " "queue size: %u", cid, NVME_QUEUE_SIZE); continue; } trace_nvme_complete_command(s, q->index, cid); preq = &q->reqs[cid - 1]; req = *preq; assert(req.cid == cid); assert(req.cb); nvme_put_free_req_locked(q, preq); preq->cb = preq->opaque = NULL; q->inflight--; qemu_mutex_unlock(&q->lock); req.cb(req.opaque, ret); qemu_mutex_lock(&q->lock); 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); nvme_wake_free_req_locked(q); } qemu_bh_cancel(q->completion_bh); return progress; } static void nvme_process_completion_bh(void *opaque) { NVMeQueuePair *q = opaque; /* * We're being invoked because a nvme_process_completion() cb() function * called aio_poll(). The callback may be waiting for further completions * so notify the device that it has space to fill in more completions now. */ smp_mb_release(); *q->cq.doorbell = cpu_to_le32(q->cq.head); nvme_wake_free_req_locked(q); nvme_process_completion(q); } static void nvme_trace_command(const NvmeCmd *cmd) { int i; if (!trace_event_get_state_backends(TRACE_NVME_SUBMIT_COMMAND_RAW)) { return; } 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(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(q->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(q); nvme_process_completion(q); qemu_mutex_unlock(&q->lock); } static void nvme_admin_cmd_sync_cb(void *opaque, int ret) { int *pret = opaque; *pret = ret; aio_wait_kick(); } static int nvme_admin_cmd_sync(BlockDriverState *bs, NvmeCmd *cmd) { BDRVNVMeState *s = bs->opaque; NVMeQueuePair *q = s->queues[INDEX_ADMIN]; AioContext *aio_context = bdrv_get_aio_context(bs); NVMeRequest *req; int ret = -EINPROGRESS; req = nvme_get_free_req(q); if (!req) { return -EBUSY; } nvme_submit_command(q, req, cmd, nvme_admin_cmd_sync_cb, &ret); AIO_WAIT_WHILE(aio_context, ret == -EINPROGRESS); return ret; } /* Returns true on success, false on failure. */ static bool nvme_identify(BlockDriverState *bs, int namespace, Error **errp) { BDRVNVMeState *s = bs->opaque; bool ret = false; union { NvmeIdCtrl ctrl; NvmeIdNs ns; } *id; NvmeLBAF *lbaf; uint16_t oncs; int r; uint64_t iova; NvmeCmd cmd = { .opcode = NVME_ADM_CMD_IDENTIFY, .cdw10 = cpu_to_le32(0x1), }; size_t id_size = QEMU_ALIGN_UP(sizeof(*id), qemu_real_host_page_size); id = qemu_try_memalign(qemu_real_host_page_size, id_size); if (!id) { error_setg(errp, "Cannot allocate buffer for identify response"); goto out; } r = qemu_vfio_dma_map(s->vfio, id, id_size, true, &iova); if (r) { error_setg(errp, "Cannot map buffer for DMA"); goto out; } memset(id, 0, id_size); cmd.dptr.prp1 = cpu_to_le64(iova); if (nvme_admin_cmd_sync(bs, &cmd)) { error_setg(errp, "Failed to identify controller"); goto out; } if (le32_to_cpu(id->ctrl.nn) < namespace) { error_setg(errp, "Invalid namespace"); goto out; } s->write_cache_supported = le32_to_cpu(id->ctrl.vwc) & 0x1; s->max_transfer = (id->ctrl.mdts ? 1 << id->ctrl.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); oncs = le16_to_cpu(id->ctrl.oncs); s->supports_write_zeroes = !!(oncs & NVME_ONCS_WRITE_ZEROES); s->supports_discard = !!(oncs & NVME_ONCS_DSM); memset(id, 0, id_size); cmd.cdw10 = 0; cmd.nsid = cpu_to_le32(namespace); if (nvme_admin_cmd_sync(bs, &cmd)) { error_setg(errp, "Failed to identify namespace"); goto out; } s->nsze = le64_to_cpu(id->ns.nsze); lbaf = &id->ns.lbaf[NVME_ID_NS_FLBAS_INDEX(id->ns.flbas)]; if (NVME_ID_NS_DLFEAT_WRITE_ZEROES(id->ns.dlfeat) && NVME_ID_NS_DLFEAT_READ_BEHAVIOR(id->ns.dlfeat) == NVME_ID_NS_DLFEAT_READ_BEHAVIOR_ZEROES) { bs->supported_write_flags |= BDRV_REQ_MAY_UNMAP; } if (lbaf->ms) { error_setg(errp, "Namespaces with metadata are not yet supported"); goto out; } if (lbaf->ds < BDRV_SECTOR_BITS || lbaf->ds > 12 || (1 << lbaf->ds) > s->page_size) { error_setg(errp, "Namespace has unsupported block size (2^%d)", lbaf->ds); goto out; } ret = true; s->blkshift = lbaf->ds; out: qemu_vfio_dma_unmap(s->vfio, id); qemu_vfree(id); return ret; } static bool nvme_poll_queue(NVMeQueuePair *q) { bool progress = false; const size_t cqe_offset = q->cq.head * NVME_CQ_ENTRY_BYTES; NvmeCqe *cqe = (NvmeCqe *)&q->cq.queue[cqe_offset]; trace_nvme_poll_queue(q->s, q->index); /* * Do an early check for completions. q->lock isn't needed because * nvme_process_completion() only runs in the event loop thread and * cannot race with itself. */ if ((le16_to_cpu(cqe->status) & 0x1) == q->cq_phase) { return false; } qemu_mutex_lock(&q->lock); while (nvme_process_completion(q)) { /* Keep polling */ progress = true; } qemu_mutex_unlock(&q->lock); return progress; } static bool nvme_poll_queues(BDRVNVMeState *s) { bool progress = false; int i; for (i = 0; i < s->queue_count; i++) { if (nvme_poll_queue(s->queues[i])) { progress = true; } } return progress; } static void nvme_handle_event(EventNotifier *n) { BDRVNVMeState *s = container_of(n, BDRVNVMeState, irq_notifier[MSIX_SHARED_IRQ_IDX]); trace_nvme_handle_event(s); event_notifier_test_and_clear(n); nvme_poll_queues(s); } static bool nvme_add_io_queue(BlockDriverState *bs, Error **errp) { BDRVNVMeState *s = bs->opaque; unsigned n = s->queue_count; NVMeQueuePair *q; NvmeCmd cmd; unsigned queue_size = NVME_QUEUE_SIZE; assert(n <= UINT16_MAX); q = nvme_create_queue_pair(s, bdrv_get_aio_context(bs), n, queue_size, errp); if (!q) { return false; } cmd = (NvmeCmd) { .opcode = NVME_ADM_CMD_CREATE_CQ, .dptr.prp1 = cpu_to_le64(q->cq.iova), .cdw10 = cpu_to_le32(((queue_size - 1) << 16) | n), .cdw11 = cpu_to_le32(NVME_CQ_IEN | NVME_CQ_PC), }; if (nvme_admin_cmd_sync(bs, &cmd)) { error_setg(errp, "Failed to create CQ io queue [%u]", n); goto out_error; } cmd = (NvmeCmd) { .opcode = NVME_ADM_CMD_CREATE_SQ, .dptr.prp1 = cpu_to_le64(q->sq.iova), .cdw10 = cpu_to_le32(((queue_size - 1) << 16) | n), .cdw11 = cpu_to_le32(NVME_SQ_PC | (n << 16)), }; if (nvme_admin_cmd_sync(bs, &cmd)) { error_setg(errp, "Failed to create SQ io queue [%u]", n); goto out_error; } s->queues = g_renew(NVMeQueuePair *, s->queues, n + 1); s->queues[n] = q; s->queue_count++; return true; out_error: nvme_free_queue_pair(q); return false; } static bool nvme_poll_cb(void *opaque) { EventNotifier *e = opaque; BDRVNVMeState *s = container_of(e, BDRVNVMeState, irq_notifier[MSIX_SHARED_IRQ_IDX]); return nvme_poll_queues(s); } static int nvme_init(BlockDriverState *bs, const char *device, int namespace, Error **errp) { BDRVNVMeState *s = bs->opaque; NVMeQueuePair *q; AioContext *aio_context = bdrv_get_aio_context(bs); int ret; uint64_t cap; uint64_t timeout_ms; uint64_t deadline, now; volatile NvmeBar *regs = NULL; qemu_co_mutex_init(&s->dma_map_lock); qemu_co_queue_init(&s->dma_flush_queue); s->device = g_strdup(device); s->nsid = namespace; s->aio_context = bdrv_get_aio_context(bs); ret = event_notifier_init(&s->irq_notifier[MSIX_SHARED_IRQ_IDX], 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 out; } regs = qemu_vfio_pci_map_bar(s->vfio, 0, 0, sizeof(NvmeBar), PROT_READ | PROT_WRITE, errp); if (!regs) { ret = -EINVAL; goto out; } /* Perform initialize sequence as described in NVMe spec "7.6.1 * Initialization". */ cap = le64_to_cpu(regs->cap); trace_nvme_controller_capability_raw(cap); trace_nvme_controller_capability("Maximum Queue Entries Supported", 1 + NVME_CAP_MQES(cap)); trace_nvme_controller_capability("Contiguous Queues Required", NVME_CAP_CQR(cap)); trace_nvme_controller_capability("Doorbell Stride", 2 << (2 + NVME_CAP_DSTRD(cap))); trace_nvme_controller_capability("Subsystem Reset Supported", NVME_CAP_NSSRS(cap)); trace_nvme_controller_capability("Memory Page Size Minimum", 1 << (12 + NVME_CAP_MPSMIN(cap))); trace_nvme_controller_capability("Memory Page Size Maximum", 1 << (12 + NVME_CAP_MPSMAX(cap))); if (!NVME_CAP_CSS(cap)) { error_setg(errp, "Device doesn't support NVMe command set"); ret = -EINVAL; goto out; } s->page_size = 1u << (12 + NVME_CAP_MPSMIN(cap)); s->doorbell_scale = (4 << NVME_CAP_DSTRD(cap)) / sizeof(uint32_t); bs->bl.opt_mem_alignment = s->page_size; bs->bl.request_alignment = s->page_size; timeout_ms = MIN(500 * NVME_CAP_TO(cap), 30000); /* Reset device to get a clean state. */ regs->cc = cpu_to_le32(le32_to_cpu(regs->cc) & 0xFE); /* Wait for CSTS.RDY = 0. */ deadline = qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + timeout_ms * SCALE_MS; while (NVME_CSTS_RDY(le32_to_cpu(regs->csts))) { 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 out; } } s->doorbells = qemu_vfio_pci_map_bar(s->vfio, 0, sizeof(NvmeBar), NVME_DOORBELL_SIZE, PROT_WRITE, errp); if (!s->doorbells) { ret = -EINVAL; goto out; } /* Set up admin queue. */ s->queues = g_new(NVMeQueuePair *, 1); q = nvme_create_queue_pair(s, aio_context, 0, NVME_QUEUE_SIZE, errp); if (!q) { ret = -EINVAL; goto out; } s->queues[INDEX_ADMIN] = q; s->queue_count = 1; QEMU_BUILD_BUG_ON((NVME_QUEUE_SIZE - 1) & 0xF000); regs->aqa = cpu_to_le32(((NVME_QUEUE_SIZE - 1) << AQA_ACQS_SHIFT) | ((NVME_QUEUE_SIZE - 1) << AQA_ASQS_SHIFT)); regs->asq = cpu_to_le64(q->sq.iova); regs->acq = cpu_to_le64(q->cq.iova); /* After setting up all control registers we can enable device now. */ regs->cc = cpu_to_le32((ctz32(NVME_CQ_ENTRY_BYTES) << CC_IOCQES_SHIFT) | (ctz32(NVME_SQ_ENTRY_BYTES) << CC_IOSQES_SHIFT) | CC_EN_MASK); /* Wait for CSTS.RDY = 1. */ now = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); deadline = now + timeout_ms * SCALE_MS; while (!NVME_CSTS_RDY(le32_to_cpu(regs->csts))) { 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 out; } } ret = qemu_vfio_pci_init_irq(s->vfio, s->irq_notifier, VFIO_PCI_MSIX_IRQ_INDEX, errp); if (ret) { goto out; } aio_set_event_notifier(bdrv_get_aio_context(bs), &s->irq_notifier[MSIX_SHARED_IRQ_IDX], false, nvme_handle_event, nvme_poll_cb); if (!nvme_identify(bs, namespace, errp)) { ret = -EIO; goto out; } /* Set up command queues. */ if (!nvme_add_io_queue(bs, errp)) { ret = -EIO; } out: if (regs) { qemu_vfio_pci_unmap_bar(s->vfio, 0, (void *)regs, 0, sizeof(NvmeBar)); } /* Cleaning up is done in nvme_file_open() upon error. */ 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_str(options, NVME_BLOCK_OPT_DEVICE, tmp); return; } device = g_strndup(tmp, slash - tmp); qdict_put_str(options, NVME_BLOCK_OPT_DEVICE, 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_str(options, NVME_BLOCK_OPT_NAMESPACE, *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_admin_cmd_sync(bs, &cmd); if (ret) { error_setg(errp, "Failed to configure NVMe write cache"); } return ret; } static void nvme_close(BlockDriverState *bs) { BDRVNVMeState *s = bs->opaque; for (unsigned i = 0; i < s->queue_count; ++i) { nvme_free_queue_pair(s->queues[i]); } g_free(s->queues); aio_set_event_notifier(bdrv_get_aio_context(bs), &s->irq_notifier[MSIX_SHARED_IRQ_IDX], false, NULL, NULL); event_notifier_cleanup(&s->irq_notifier[MSIX_SHARED_IRQ_IDX]); qemu_vfio_pci_unmap_bar(s->vfio, 0, (void *)s->doorbells, sizeof(NvmeBar), NVME_DOORBELL_SIZE); qemu_vfio_close(s->vfio); g_free(s->device); } 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; bs->supported_write_flags = BDRV_REQ_FUA; 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; } } return 0; fail: nvme_close(bs); return ret; } static int64_t nvme_getlength(BlockDriverState *bs) { BDRVNVMeState *s = bs->opaque; return s->nsze << s->blkshift; } static uint32_t nvme_get_blocksize(BlockDriverState *bs) { BDRVNVMeState *s = bs->opaque; assert(s->blkshift >= BDRV_SECTOR_BITS && s->blkshift <= 12); return UINT32_C(1) << s->blkshift; } static int nvme_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz) { uint32_t blocksize = nvme_get_blocksize(bs); bsz->phys = blocksize; bsz->log = blocksize; return 0; } /* 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; size_t len = QEMU_ALIGN_UP(qiov->iov[i].iov_len, qemu_real_host_page_size); try_map: r = qemu_vfio_dma_map(s->vfio, qiov->iov[i].iov_base, 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++] = cpu_to_le64(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->dptr.prp1 = pagelist[0]; cmd->dptr.prp2 = 0; break; case 2: cmd->dptr.prp1 = pagelist[0]; cmd->dptr.prp2 = pagelist[1]; break; default: cmd->dptr.prp1 = pagelist[0]; cmd->dptr.prp2 = cpu_to_le64(req->prp_list_iova + sizeof(uint64_t)); 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; } replay_bh_schedule_oneshot_event(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[INDEX_IO(0)]; NVMeRequest *req; uint32_t cdw12 = (((bytes >> s->blkshift) - 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 >> s->blkshift) & 0xFFFFFFFF), .cdw11 = cpu_to_le32(((offset >> s->blkshift) >> 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->queue_count > 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) { nvme_put_free_req_and_wake(ioq, req); return r; } nvme_submit_command(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, qemu_real_host_page_size) || !QEMU_IS_ALIGNED(qiov->iov[i].iov_len, qemu_real_host_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; size_t len = QEMU_ALIGN_UP(bytes, qemu_real_host_page_size); 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)) { s->stats.aligned_accesses++; return nvme_co_prw_aligned(bs, offset, bytes, qiov, is_write, flags); } s->stats.unaligned_accesses++; trace_nvme_prw_buffered(s, offset, bytes, qiov->niov, is_write); buf = qemu_try_memalign(qemu_real_host_page_size, len); 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[INDEX_IO(0)]; 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->queue_count > 1); req = nvme_get_free_req(ioq); assert(req); nvme_submit_command(ioq, req, &cmd, nvme_rw_cb, &data); data.co = qemu_coroutine_self(); if (data.ret == -EINPROGRESS) { qemu_coroutine_yield(); } return data.ret; } static coroutine_fn int nvme_co_pwrite_zeroes(BlockDriverState *bs, int64_t offset, int bytes, BdrvRequestFlags flags) { BDRVNVMeState *s = bs->opaque; NVMeQueuePair *ioq = s->queues[INDEX_IO(0)]; NVMeRequest *req; uint32_t cdw12 = ((bytes >> s->blkshift) - 1) & 0xFFFF; if (!s->supports_write_zeroes) { return -ENOTSUP; } NvmeCmd cmd = { .opcode = NVME_CMD_WRITE_ZEROES, .nsid = cpu_to_le32(s->nsid), .cdw10 = cpu_to_le32((offset >> s->blkshift) & 0xFFFFFFFF), .cdw11 = cpu_to_le32(((offset >> s->blkshift) >> 32) & 0xFFFFFFFF), }; NVMeCoData data = { .ctx = bdrv_get_aio_context(bs), .ret = -EINPROGRESS, }; if (flags & BDRV_REQ_MAY_UNMAP) { cdw12 |= (1 << 25); } if (flags & BDRV_REQ_FUA) { cdw12 |= (1 << 30); } cmd.cdw12 = cpu_to_le32(cdw12); trace_nvme_write_zeroes(s, offset, bytes, flags); assert(s->queue_count > 1); req = nvme_get_free_req(ioq); assert(req); nvme_submit_command(ioq, req, &cmd, nvme_rw_cb, &data); data.co = qemu_coroutine_self(); while (data.ret == -EINPROGRESS) { qemu_coroutine_yield(); } trace_nvme_rw_done(s, true, offset, bytes, data.ret); return data.ret; } static int coroutine_fn nvme_co_pdiscard(BlockDriverState *bs, int64_t offset, int bytes) { BDRVNVMeState *s = bs->opaque; NVMeQueuePair *ioq = s->queues[INDEX_IO(0)]; NVMeRequest *req; NvmeDsmRange *buf; QEMUIOVector local_qiov; int ret; NvmeCmd cmd = { .opcode = NVME_CMD_DSM, .nsid = cpu_to_le32(s->nsid), .cdw10 = cpu_to_le32(0), /*number of ranges - 0 based*/ .cdw11 = cpu_to_le32(1 << 2), /*deallocate bit*/ }; NVMeCoData data = { .ctx = bdrv_get_aio_context(bs), .ret = -EINPROGRESS, }; if (!s->supports_discard) { return -ENOTSUP; } assert(s->queue_count > 1); buf = qemu_try_memalign(s->page_size, s->page_size); if (!buf) { return -ENOMEM; } memset(buf, 0, s->page_size); buf->nlb = cpu_to_le32(bytes >> s->blkshift); buf->slba = cpu_to_le64(offset >> s->blkshift); buf->cattr = 0; qemu_iovec_init(&local_qiov, 1); qemu_iovec_add(&local_qiov, buf, 4096); req = nvme_get_free_req(ioq); assert(req); qemu_co_mutex_lock(&s->dma_map_lock); ret = nvme_cmd_map_qiov(bs, &cmd, req, &local_qiov); qemu_co_mutex_unlock(&s->dma_map_lock); if (ret) { nvme_put_free_req_and_wake(ioq, req); goto out; } trace_nvme_dsm(s, offset, bytes); nvme_submit_command(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); ret = nvme_cmd_unmap_qiov(bs, &local_qiov); qemu_co_mutex_unlock(&s->dma_map_lock); if (ret) { goto out; } ret = data.ret; trace_nvme_dsm_done(s, offset, bytes, ret); out: qemu_iovec_destroy(&local_qiov); qemu_vfree(buf); return ret; } static int nvme_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue, Error **errp) { return 0; } static void nvme_refresh_filename(BlockDriverState *bs) { BDRVNVMeState *s = bs->opaque; snprintf(bs->exact_filename, sizeof(bs->exact_filename), "nvme://%s/%i", s->device, s->nsid); } 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; for (unsigned i = 0; i < s->queue_count; i++) { NVMeQueuePair *q = s->queues[i]; qemu_bh_delete(q->completion_bh); q->completion_bh = NULL; } aio_set_event_notifier(bdrv_get_aio_context(bs), &s->irq_notifier[MSIX_SHARED_IRQ_IDX], 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[MSIX_SHARED_IRQ_IDX], false, nvme_handle_event, nvme_poll_cb); for (unsigned i = 0; i < s->queue_count; i++) { NVMeQueuePair *q = s->queues[i]; q->completion_bh = aio_bh_new(new_context, nvme_process_completion_bh, q); } } static void nvme_aio_plug(BlockDriverState *bs) { BDRVNVMeState *s = bs->opaque; assert(!s->plugged); s->plugged = true; } static void nvme_aio_unplug(BlockDriverState *bs) { BDRVNVMeState *s = bs->opaque; assert(s->plugged); s->plugged = false; for (unsigned i = INDEX_IO(0); i < s->queue_count; i++) { NVMeQueuePair *q = s->queues[i]; qemu_mutex_lock(&q->lock); nvme_kick(q); nvme_process_completion(q); qemu_mutex_unlock(&q->lock); } } static void nvme_register_buf(BlockDriverState *bs, void *host, size_t size) { int ret; BDRVNVMeState *s = bs->opaque; ret = qemu_vfio_dma_map(s->vfio, host, size, false, NULL); if (ret) { /* FIXME: we may run out of IOVA addresses after repeated * bdrv_register_buf/bdrv_unregister_buf, because nvme_vfio_dma_unmap * doesn't reclaim addresses for fixed mappings. */ error_report("nvme_register_buf failed: %s", strerror(-ret)); } } static void nvme_unregister_buf(BlockDriverState *bs, void *host) { BDRVNVMeState *s = bs->opaque; qemu_vfio_dma_unmap(s->vfio, host); } static BlockStatsSpecific *nvme_get_specific_stats(BlockDriverState *bs) { BlockStatsSpecific *stats = g_new(BlockStatsSpecific, 1); BDRVNVMeState *s = bs->opaque; stats->driver = BLOCKDEV_DRIVER_NVME; stats->u.nvme = (BlockStatsSpecificNvme) { .completion_errors = s->stats.completion_errors, .aligned_accesses = s->stats.aligned_accesses, .unaligned_accesses = s->stats.unaligned_accesses, }; return stats; } static const char *const nvme_strong_runtime_opts[] = { NVME_BLOCK_OPT_DEVICE, NVME_BLOCK_OPT_NAMESPACE, NULL }; static BlockDriver bdrv_nvme = { .format_name = "nvme", .protocol_name = "nvme", .instance_size = sizeof(BDRVNVMeState), .bdrv_co_create_opts = bdrv_co_create_opts_simple, .create_opts = &bdrv_create_opts_simple, .bdrv_parse_filename = nvme_parse_filename, .bdrv_file_open = nvme_file_open, .bdrv_close = nvme_close, .bdrv_getlength = nvme_getlength, .bdrv_probe_blocksizes = nvme_probe_blocksizes, .bdrv_co_preadv = nvme_co_preadv, .bdrv_co_pwritev = nvme_co_pwritev, .bdrv_co_pwrite_zeroes = nvme_co_pwrite_zeroes, .bdrv_co_pdiscard = nvme_co_pdiscard, .bdrv_co_flush_to_disk = nvme_co_flush, .bdrv_reopen_prepare = nvme_reopen_prepare, .bdrv_refresh_filename = nvme_refresh_filename, .bdrv_refresh_limits = nvme_refresh_limits, .strong_runtime_opts = nvme_strong_runtime_opts, .bdrv_get_specific_stats = nvme_get_specific_stats, .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, .bdrv_register_buf = nvme_register_buf, .bdrv_unregister_buf = nvme_unregister_buf, }; static void bdrv_nvme_init(void) { bdrv_register(&bdrv_nvme); } block_init(bdrv_nvme_init);