virtio: add AioContext-specific function for host notifiers

This is used to register ioeventfd with a dataplane thread.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>

1 files changed, 16 insertions, 0 deletions

diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index e365960bd7..f419e7cb57 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -1786,6 +1786,22 @@ static void virtio_queue_host_notifier_read(EventNotifier *n)
     }
 }
 
+void virtio_queue_aio_set_host_notifier_handler(VirtQueue *vq, AioContext *ctx,
+                                                bool assign, bool set_handler)
+{
+    if (assign && set_handler) {
+        aio_set_event_notifier(ctx, &vq->host_notifier, true,
+                               virtio_queue_host_notifier_read);
+    } else {
+        aio_set_event_notifier(ctx, &vq->host_notifier, true, NULL);
+    }
+    if (!assign) {
+        /* Test and clear notifier before after disabling event,
+         * in case poll callback didn't have time to run. */
+        virtio_queue_host_notifier_read(&vq->host_notifier);
+    }
+}
+
 void virtio_queue_set_host_notifier_fd_handler(VirtQueue *vq, bool assign,
                                                bool set_handler)
 {