virtio: move common ioeventfd handling out of virtio-pci

All transports can use the same event handler for the ioeventfd, though
the exact setup (address/memory region) will be specific.

This lets virtio use event_notifier_set_handler.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 22 insertions, 0 deletions

diff --git a/hw/virtio.c b/hw/virtio.c
index 168abe4864..197edf00f4 100644
--- a/hw/virtio.c
+++ b/hw/virtio.c
@@ -988,6 +988,28 @@ EventNotifier *virtio_queue_get_guest_notifier(VirtQueue *vq)
 {
     return &vq->guest_notifier;
 }
+
+static void virtio_queue_host_notifier_read(EventNotifier *n)
+{
+    VirtQueue *vq = container_of(n, VirtQueue, host_notifier);
+    if (event_notifier_test_and_clear(n)) {
+        virtio_queue_notify_vq(vq);
+    }
+}
+
+void virtio_queue_set_host_notifier_fd_handler(VirtQueue *vq, bool assign)
+{
+    if (assign) {
+        event_notifier_set_handler(&vq->host_notifier,
+                                   virtio_queue_host_notifier_read);
+    } else {
+        event_notifier_set_handler(&vq->host_notifier, NULL);
+        /* 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);
+    }
+}
+
 EventNotifier *virtio_queue_get_host_notifier(VirtQueue *vq)
 {
     return &vq->host_notifier;