virtio-bus: have callers tolerate new host notifier api

Have vhost and dataplane use the new api for transports that
have been converted.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

1 files changed, 11 insertions, 3 deletions

diff --git a/hw/block/dataplane/virtio-blk.c b/hw/block/dataplane/virtio-blk.c
index 2073f9a270..fdf5fd1190 100644
--- a/hw/block/dataplane/virtio-blk.c
+++ b/hw/block/dataplane/virtio-blk.c
@@ -79,7 +79,8 @@ void virtio_blk_data_plane_create(VirtIODevice *vdev, VirtIOBlkConf *conf,
     }
 
     /* Don't try if transport does not support notifiers. */
-    if (!k->set_guest_notifiers || !k->set_host_notifier) {
+    if (!k->set_guest_notifiers ||
+        (!k->set_host_notifier && !k->ioeventfd_started)) {
         error_setg(errp,
                    "device is incompatible with dataplane "
                    "(transport does not support notifiers)");
@@ -157,7 +158,10 @@ void virtio_blk_data_plane_start(VirtIOBlockDataPlane *s)
     s->guest_notifier = virtio_queue_get_guest_notifier(s->vq);
 
     /* Set up virtqueue notify */
-    r = k->set_host_notifier(qbus->parent, 0, true);
+    r = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), 0, true);
+    if (r == -ENOSYS) {
+        r = k->set_host_notifier(qbus->parent, 0, true);
+    }
     if (r != 0) {
         fprintf(stderr, "virtio-blk failed to set host notifier (%d)\n", r);
         goto fail_host_notifier;
@@ -193,6 +197,7 @@ void virtio_blk_data_plane_stop(VirtIOBlockDataPlane *s)
     BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(s->vdev)));
     VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
     VirtIOBlock *vblk = VIRTIO_BLK(s->vdev);
+    int r;
 
     if (!vblk->dataplane_started || s->stopping) {
         return;
@@ -217,7 +222,10 @@ void virtio_blk_data_plane_stop(VirtIOBlockDataPlane *s)
 
     aio_context_release(s->ctx);
 
-    k->set_host_notifier(qbus->parent, 0, false);
+    r = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), 0, false);
+    if (r == -ENOSYS) {
+        k->set_host_notifier(qbus->parent, 0, false);
+    }
 
     /* Clean up guest notifier (irq) */
     k->set_guest_notifiers(qbus->parent, 1, false);