virtio: move ioeventfd_started flag to VirtioBusState

This simplifies the code and removes the ioeventfd_started
and ioeventfd_set_started callback.  The only difference is
in how virtio-ccw handles an error---it doesn't disable
ioeventfd forever anymore.  It was the only backend to do
so, and if desired this behavior should be implemented in

virtio-bus.c.

Instead of ioeventfd_started, the ioeventfd_assign callback now
determines whether the virtio bus supports host notifiers.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
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>

1 files changed, 1 insertions, 1 deletions

diff --git a/hw/scsi/virtio-scsi-dataplane.c b/hw/scsi/virtio-scsi-dataplane.c
index b173b94949..f537b4e900 100644
--- a/hw/scsi/virtio-scsi-dataplane.c
+++ b/hw/scsi/virtio-scsi-dataplane.c
@@ -31,7 +31,7 @@ void virtio_scsi_set_iothread(VirtIOSCSI *s, IOThread *iothread)
     s->ctx = iothread_get_aio_context(vs->conf.iothread);
 
     /* Don't try if transport does not support notifiers. */
-    if (!k->set_guest_notifiers || !k->ioeventfd_started) {
+    if (!k->set_guest_notifiers || !k->ioeventfd_assign) {
         fprintf(stderr, "virtio-scsi: Failed to set iothread "
                    "(transport does not support notifiers)");
         exit(1);