[PATCH v3 4/5] virtio-mmio: add support for configure interrupt

[Cindy Lu <lulu@redhat.com>]

add configure interrupt support for virtio-mmio bus. This
interrupt will working while backend is vhost-vdpa

Signed-off-by: Cindy Lu <lulu@redhat.com>
---
 hw/virtio/virtio-mmio.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/hw/virtio/virtio-mmio.c b/hw/virtio/virtio-mmio.c
index e1b5c3b81e..d580f1ea9a 100644
--- a/hw/virtio/virtio-mmio.c
+++ b/hw/virtio/virtio-mmio.c
@@ -666,6 +666,21 @@ assign_error:
     return r;
 }
 
+static int virtio_mmio_set_config_notifier(DeviceState *d,  bool assign)
+{
+    VirtIOMMIOProxy *proxy = VIRTIO_MMIO(d);
+    VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
+    EventNotifier *notifier = virtio_get_config_notifier(vdev);
+    int r = 0;
+    if (assign) {
+        r = event_notifier_init(notifier, 0);
+        virtio_set_config_notifier_fd_handler(vdev, true, false);
+    } else {
+        virtio_set_config_notifier_fd_handler(vdev, false, false);
+        event_notifier_cleanup(notifier);
+    }
+    return r;
+}
 static void virtio_mmio_pre_plugged(DeviceState *d, Error **errp)
 {
     VirtIOMMIOProxy *proxy = VIRTIO_MMIO(d);
@@ -780,6 +795,7 @@ static void virtio_mmio_bus_class_init(ObjectClass *klass, void *data)
     k->ioeventfd_assign = virtio_mmio_ioeventfd_assign;
     k->pre_plugged = virtio_mmio_pre_plugged;
     k->has_variable_vring_alignment = true;
+    k->set_config_notifiers = virtio_mmio_set_config_notifier;
     bus_class->max_dev = 1;
     bus_class->get_dev_path = virtio_mmio_bus_get_dev_path;
 }
-- 
2.21.3