qemu-kvm/kvm-virtio-pci-add-support-for-configure-interrupt.patch

From 61ac1476d3820c97e1cc103af422b17bc94c6ca5 Mon Sep 17 00:00:00 2001
From: Cindy Lu <lulu@redhat.com>
Date: Thu, 22 Dec 2022 15:04:51 +0800
Subject: [PATCH 10/31] virtio-pci: add support for configure interrupt
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RH-Author: Cindy Lu <lulu@redhat.com>
RH-MergeRequest: 132: vhost-vdpa: support config interrupt in vhost-vdpa
RH-Bugzilla: 1905805
RH-Acked-by: Laurent Vivier <lvivier@redhat.com>
RH-Acked-by: Eugenio Pérez <eperezma@redhat.com>
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Commit: [10/10] ebd6a11d7699660d8ac5a4e44a790f823daea57c (lulu6/qemu-kvm3)

https://bugzilla.redhat.com/show_bug.cgi?id=1905805
Add process to handle the configure interrupt, The function's
logic is the same with vq interrupt.Add extra process to check
the configure interrupt

Signed-off-by: Cindy Lu <lulu@redhat.com>
Message-Id: <20221222070451.936503-11-lulu@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
(cherry picked from commit 1680542862edd963e6380dd4121a5e85df55581f)
Signed-off-by: Cindy Lu <lulu@redhat.com>
---
 hw/virtio/virtio-pci.c         | 118 +++++++++++++++++++++++++++------
 include/hw/virtio/virtio-pci.h |   4 +-
 2 files changed, 102 insertions(+), 20 deletions(-)

diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
index ec816ea367..3f00e91718 100644
--- a/hw/virtio/virtio-pci.c
+++ b/hw/virtio/virtio-pci.c
@@ -751,7 +751,8 @@ static int virtio_pci_get_notifier(VirtIOPCIProxy *proxy, int queue_no,
     VirtQueue *vq;
 
     if (queue_no == VIRTIO_CONFIG_IRQ_IDX) {
-        return -1;
+        *n = virtio_config_get_guest_notifier(vdev);
+        *vector = vdev->config_vector;
     } else {
         if (!virtio_queue_get_num(vdev, queue_no)) {
             return -1;
@@ -811,7 +812,7 @@ undo:
     }
     return ret;
 }
-static int kvm_virtio_pci_vector_use(VirtIOPCIProxy *proxy, int nvqs)
+static int kvm_virtio_pci_vector_vq_use(VirtIOPCIProxy *proxy, int nvqs)
 {
     int queue_no;
     int ret = 0;
@@ -826,6 +827,10 @@ static int kvm_virtio_pci_vector_use(VirtIOPCIProxy *proxy, int nvqs)
     return ret;
 }
 
+static int kvm_virtio_pci_vector_config_use(VirtIOPCIProxy *proxy)
+{
+    return kvm_virtio_pci_vector_use_one(proxy, VIRTIO_CONFIG_IRQ_IDX);
+}
 
 static void kvm_virtio_pci_vector_release_one(VirtIOPCIProxy *proxy,
                                               int queue_no)
@@ -850,7 +855,7 @@ static void kvm_virtio_pci_vector_release_one(VirtIOPCIProxy *proxy,
     kvm_virtio_pci_vq_vector_release(proxy, vector);
 }
 
-static void kvm_virtio_pci_vector_release(VirtIOPCIProxy *proxy, int nvqs)
+static void kvm_virtio_pci_vector_vq_release(VirtIOPCIProxy *proxy, int nvqs)
 {
     int queue_no;
     VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
@@ -863,6 +868,11 @@ static void kvm_virtio_pci_vector_release(VirtIOPCIProxy *proxy, int nvqs)
     }
 }
 
+static void kvm_virtio_pci_vector_config_release(VirtIOPCIProxy *proxy)
+{
+    kvm_virtio_pci_vector_release_one(proxy, VIRTIO_CONFIG_IRQ_IDX);
+}
+
 static int virtio_pci_one_vector_unmask(VirtIOPCIProxy *proxy,
                                        unsigned int queue_no,
                                        unsigned int vector,
@@ -944,9 +954,19 @@ static int virtio_pci_vector_unmask(PCIDevice *dev, unsigned vector,
         }
         vq = virtio_vector_next_queue(vq);
     }
-
+    /* unmask config intr */
+    if (vector == vdev->config_vector) {
+        n = virtio_config_get_guest_notifier(vdev);
+        ret = virtio_pci_one_vector_unmask(proxy, VIRTIO_CONFIG_IRQ_IDX, vector,
+                                           msg, n);
+        if (ret < 0) {
+            goto undo_config;
+        }
+    }
     return 0;
-
+undo_config:
+    n = virtio_config_get_guest_notifier(vdev);
+    virtio_pci_one_vector_mask(proxy, VIRTIO_CONFIG_IRQ_IDX, vector, n);
 undo:
     vq = virtio_vector_first_queue(vdev, vector);
     while (vq && unmasked >= 0) {
@@ -980,6 +1000,11 @@ static void virtio_pci_vector_mask(PCIDevice *dev, unsigned vector)
         }
         vq = virtio_vector_next_queue(vq);
     }
+
+    if (vector == vdev->config_vector) {
+        n = virtio_config_get_guest_notifier(vdev);
+        virtio_pci_one_vector_mask(proxy, VIRTIO_CONFIG_IRQ_IDX, vector, n);
+    }
 }
 
 static void virtio_pci_vector_poll(PCIDevice *dev,
@@ -1011,6 +1036,34 @@ static void virtio_pci_vector_poll(PCIDevice *dev,
             msix_set_pending(dev, vector);
         }
     }
+    /* poll the config intr */
+    ret = virtio_pci_get_notifier(proxy, VIRTIO_CONFIG_IRQ_IDX, &notifier,
+                                  &vector);
+    if (ret < 0) {
+        return;
+    }
+    if (vector < vector_start || vector >= vector_end ||
+        !msix_is_masked(dev, vector)) {
+        return;
+    }
+    if (k->guest_notifier_pending) {
+        if (k->guest_notifier_pending(vdev, VIRTIO_CONFIG_IRQ_IDX)) {
+            msix_set_pending(dev, vector);
+        }
+    } else if (event_notifier_test_and_clear(notifier)) {
+        msix_set_pending(dev, vector);
+    }
+}
+
+void virtio_pci_set_guest_notifier_fd_handler(VirtIODevice *vdev, VirtQueue *vq,
+                                              int n, bool assign,
+                                              bool with_irqfd)
+{
+    if (n == VIRTIO_CONFIG_IRQ_IDX) {
+        virtio_config_set_guest_notifier_fd_handler(vdev, assign, with_irqfd);
+    } else {
+        virtio_queue_set_guest_notifier_fd_handler(vq, assign, with_irqfd);
+    }
 }
 
 static int virtio_pci_set_guest_notifier(DeviceState *d, int n, bool assign,
@@ -1019,17 +1072,25 @@ static int virtio_pci_set_guest_notifier(DeviceState *d, int n, bool assign,
     VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);
     VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
     VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev);
-    VirtQueue *vq = virtio_get_queue(vdev, n);
-    EventNotifier *notifier = virtio_queue_get_guest_notifier(vq);
+    VirtQueue *vq = NULL;
+    EventNotifier *notifier = NULL;
+
+    if (n == VIRTIO_CONFIG_IRQ_IDX) {
+        notifier = virtio_config_get_guest_notifier(vdev);
+    } else {
+        vq = virtio_get_queue(vdev, n);
+        notifier = virtio_queue_get_guest_notifier(vq);
+    }
 
     if (assign) {
         int r = event_notifier_init(notifier, 0);
         if (r < 0) {
             return r;
         }
-        virtio_queue_set_guest_notifier_fd_handler(vq, true, with_irqfd);
+        virtio_pci_set_guest_notifier_fd_handler(vdev, vq, n, true, with_irqfd);
     } else {
-        virtio_queue_set_guest_notifier_fd_handler(vq, false, with_irqfd);
+        virtio_pci_set_guest_notifier_fd_handler(vdev, vq, n, false,
+                                                 with_irqfd);
         event_notifier_cleanup(notifier);
     }
 
@@ -1072,10 +1133,13 @@ static int virtio_pci_set_guest_notifiers(DeviceState *d, int nvqs, bool assign)
     proxy->nvqs_with_notifiers = nvqs;
 
     /* Must unset vector notifier while guest notifier is still assigned */
-    if ((proxy->vector_irqfd || k->guest_notifier_mask) && !assign) {
+    if ((proxy->vector_irqfd ||
+         (vdev->use_guest_notifier_mask && k->guest_notifier_mask)) &&
+        !assign) {
         msix_unset_vector_notifiers(&proxy->pci_dev);
         if (proxy->vector_irqfd) {
-            kvm_virtio_pci_vector_release(proxy, nvqs);
+            kvm_virtio_pci_vector_vq_release(proxy, nvqs);
+            kvm_virtio_pci_vector_config_release(proxy);
             g_free(proxy->vector_irqfd);
             proxy->vector_irqfd = NULL;
         }
@@ -1091,20 +1155,30 @@ static int virtio_pci_set_guest_notifiers(DeviceState *d, int nvqs, bool assign)
             goto assign_error;
         }
     }
-
+    r = virtio_pci_set_guest_notifier(d, VIRTIO_CONFIG_IRQ_IDX, assign,
+                                      with_irqfd);
+    if (r < 0) {
+        goto config_assign_error;
+    }
     /* Must set vector notifier after guest notifier has been assigned */
-    if ((with_irqfd || k->guest_notifier_mask) && assign) {
+    if ((with_irqfd ||
+         (vdev->use_guest_notifier_mask && k->guest_notifier_mask)) &&
+        assign) {
         if (with_irqfd) {
             proxy->vector_irqfd =
                 g_malloc0(sizeof(*proxy->vector_irqfd) *
                           msix_nr_vectors_allocated(&proxy->pci_dev));
-            r = kvm_virtio_pci_vector_use(proxy, nvqs);
+            r = kvm_virtio_pci_vector_vq_use(proxy, nvqs);
+            if (r < 0) {
+                goto config_assign_error;
+            }
+            r = kvm_virtio_pci_vector_config_use(proxy);
             if (r < 0) {
-                goto assign_error;
+                goto config_error;
             }
         }
-        r = msix_set_vector_notifiers(&proxy->pci_dev,
-                                      virtio_pci_vector_unmask,
+
+        r = msix_set_vector_notifiers(&proxy->pci_dev, virtio_pci_vector_unmask,
                                       virtio_pci_vector_mask,
                                       virtio_pci_vector_poll);
         if (r < 0) {
@@ -1117,9 +1191,15 @@ static int virtio_pci_set_guest_notifiers(DeviceState *d, int nvqs, bool assign)
 notifiers_error:
     if (with_irqfd) {
         assert(assign);
-        kvm_virtio_pci_vector_release(proxy, nvqs);
+        kvm_virtio_pci_vector_vq_release(proxy, nvqs);
     }
-
+config_error:
+    if (with_irqfd) {
+        kvm_virtio_pci_vector_config_release(proxy);
+    }
+config_assign_error:
+    virtio_pci_set_guest_notifier(d, VIRTIO_CONFIG_IRQ_IDX, !assign,
+                                  with_irqfd);
 assign_error:
     /* We get here on assignment failure. Recover by undoing for VQs 0 .. n. */
     assert(assign);
diff --git a/include/hw/virtio/virtio-pci.h b/include/hw/virtio/virtio-pci.h
index 938799e8f6..c02e278f46 100644
--- a/include/hw/virtio/virtio-pci.h
+++ b/include/hw/virtio/virtio-pci.h
@@ -256,5 +256,7 @@ void virtio_pci_types_register(const VirtioPCIDeviceTypeInfo *t);
  * @fixed_queues.
  */
 unsigned virtio_pci_optimal_num_queues(unsigned fixed_queues);
-
+void virtio_pci_set_guest_notifier_fd_handler(VirtIODevice *vdev, VirtQueue *vq,
+                                              int n, bool assign,
+                                              bool with_irqfd);
 #endif
-- 
2.31.1