1 files changed, 112 insertions, 1 deletions

diff --git a/hw/nvme/ctrl.c b/hw/nvme/ctrl.c
index 55cb0ba1d5..533ad14e7a 100644
--- a/hw/nvme/ctrl.c
+++ b/hw/nvme/ctrl.c
@@ -1400,7 +1400,14 @@ static void nvme_enqueue_req_completion(NvmeCQueue *cq, NvmeRequest *req)
 
     QTAILQ_REMOVE(&req->sq->out_req_list, req, entry);
     QTAILQ_INSERT_TAIL(&cq->req_list, req, entry);
-    timer_mod(cq->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + 500);
+
+    if (req->sq->ioeventfd_enabled) {
+        /* Post CQE directly since we are in main loop thread */
+        nvme_post_cqes(cq);
+    } else {
+        /* Schedule the timer to post CQE later since we are in vcpu thread */
+        timer_mod(cq->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + 500);
+    }
 }
 
 static void nvme_process_aers(void *opaque)
@@ -4226,10 +4233,82 @@ static uint16_t nvme_io_cmd(NvmeCtrl *n, NvmeRequest *req)
     return NVME_INVALID_OPCODE | NVME_DNR;
 }
 
+static void nvme_cq_notifier(EventNotifier *e)
+{
+    NvmeCQueue *cq = container_of(e, NvmeCQueue, notifier);
+    NvmeCtrl *n = cq->ctrl;
+
+    event_notifier_test_and_clear(&cq->notifier);
+
+    nvme_update_cq_head(cq);
+
+    if (cq->tail == cq->head) {
+        if (cq->irq_enabled) {
+            n->cq_pending--;
+        }
+
+        nvme_irq_deassert(n, cq);
+    }
+
+    nvme_post_cqes(cq);
+}
+
+static int nvme_init_cq_ioeventfd(NvmeCQueue *cq)
+{
+    NvmeCtrl *n = cq->ctrl;
+    uint16_t offset = (cq->cqid << 3) + (1 << 2);
+    int ret;
+
+    ret = event_notifier_init(&cq->notifier, 0);
+    if (ret < 0) {
+        return ret;
+    }
+
+    event_notifier_set_handler(&cq->notifier, nvme_cq_notifier);
+    memory_region_add_eventfd(&n->iomem,
+                              0x1000 + offset, 4, false, 0, &cq->notifier);
+
+    return 0;
+}
+
+static void nvme_sq_notifier(EventNotifier *e)
+{
+    NvmeSQueue *sq = container_of(e, NvmeSQueue, notifier);
+
+    event_notifier_test_and_clear(&sq->notifier);
+
+    nvme_process_sq(sq);
+}
+
+static int nvme_init_sq_ioeventfd(NvmeSQueue *sq)
+{
+    NvmeCtrl *n = sq->ctrl;
+    uint16_t offset = sq->sqid << 3;
+    int ret;
+
+    ret = event_notifier_init(&sq->notifier, 0);
+    if (ret < 0) {
+        return ret;
+    }
+
+    event_notifier_set_handler(&sq->notifier, nvme_sq_notifier);
+    memory_region_add_eventfd(&n->iomem,
+                              0x1000 + offset, 4, false, 0, &sq->notifier);
+
+    return 0;
+}
+
 static void nvme_free_sq(NvmeSQueue *sq, NvmeCtrl *n)
 {
+    uint16_t offset = sq->sqid << 3;
+
     n->sq[sq->sqid] = NULL;
     timer_free(sq->timer);
+    if (sq->ioeventfd_enabled) {
+        memory_region_del_eventfd(&n->iomem,
+                                  0x1000 + offset, 4, false, 0, &sq->notifier);
+        event_notifier_cleanup(&sq->notifier);
+    }
     g_free(sq->io_req);
     if (sq->sqid) {
         g_free(sq);
@@ -4302,6 +4381,12 @@ static void nvme_init_sq(NvmeSQueue *sq, NvmeCtrl *n, uint64_t dma_addr,
     if (n->dbbuf_enabled) {
         sq->db_addr = n->dbbuf_dbs + (sqid << 3);
         sq->ei_addr = n->dbbuf_eis + (sqid << 3);
+
+        if (n->params.ioeventfd && sq->sqid != 0) {
+            if (!nvme_init_sq_ioeventfd(sq)) {
+                sq->ioeventfd_enabled = true;
+            }
+        }
     }
 
     assert(n->cq[cqid]);
@@ -4605,8 +4690,15 @@ static uint16_t nvme_get_log(NvmeCtrl *n, NvmeRequest *req)
 
 static void nvme_free_cq(NvmeCQueue *cq, NvmeCtrl *n)
 {
+    uint16_t offset = (cq->cqid << 3) + (1 << 2);
+
     n->cq[cq->cqid] = NULL;
     timer_free(cq->timer);
+    if (cq->ioeventfd_enabled) {
+        memory_region_del_eventfd(&n->iomem,
+                                  0x1000 + offset, 4, false, 0, &cq->notifier);
+        event_notifier_cleanup(&cq->notifier);
+    }
     if (msix_enabled(&n->parent_obj)) {
         msix_vector_unuse(&n->parent_obj, cq->vector);
     }
@@ -4665,6 +4757,12 @@ static void nvme_init_cq(NvmeCQueue *cq, NvmeCtrl *n, uint64_t dma_addr,
     if (n->dbbuf_enabled) {
         cq->db_addr = n->dbbuf_dbs + (cqid << 3) + (1 << 2);
         cq->ei_addr = n->dbbuf_eis + (cqid << 3) + (1 << 2);
+
+        if (n->params.ioeventfd && cqid != 0) {
+            if (!nvme_init_cq_ioeventfd(cq)) {
+                cq->ioeventfd_enabled = true;
+            }
+        }
     }
     n->cq[cqid] = cq;
     cq->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, nvme_post_cqes, cq);
@@ -6039,6 +6137,12 @@ static uint16_t nvme_dbbuf_config(NvmeCtrl *n, const NvmeRequest *req)
             sq->ei_addr = eis_addr + (i << 3);
             pci_dma_write(&n->parent_obj, sq->db_addr, &sq->tail,
                     sizeof(sq->tail));
+
+            if (n->params.ioeventfd && sq->sqid != 0) {
+                if (!nvme_init_sq_ioeventfd(sq)) {
+                    sq->ioeventfd_enabled = true;
+                }
+            }
         }
 
         if (cq) {
@@ -6047,6 +6151,12 @@ static uint16_t nvme_dbbuf_config(NvmeCtrl *n, const NvmeRequest *req)
             cq->ei_addr = eis_addr + (i << 3) + (1 << 2);
             pci_dma_write(&n->parent_obj, cq->db_addr, &cq->head,
                     sizeof(cq->head));
+
+            if (n->params.ioeventfd && cq->cqid != 0) {
+                if (!nvme_init_cq_ioeventfd(cq)) {
+                    cq->ioeventfd_enabled = true;
+                }
+            }
         }
     }
 
@@ -7554,6 +7664,7 @@ static Property nvme_props[] = {
     DEFINE_PROP_UINT8("vsl", NvmeCtrl, params.vsl, 7),
     DEFINE_PROP_BOOL("use-intel-id", NvmeCtrl, params.use_intel_id, false),
     DEFINE_PROP_BOOL("legacy-cmb", NvmeCtrl, params.legacy_cmb, false),
+    DEFINE_PROP_BOOL("ioeventfd", NvmeCtrl, params.ioeventfd, true),
     DEFINE_PROP_UINT8("zoned.zasl", NvmeCtrl, params.zasl, 0),
     DEFINE_PROP_BOOL("zoned.auto_transition", NvmeCtrl,
                      params.auto_transition_zones, true),