void virtio_bus_stop_ioeventfd(VirtioBusState *bus)
{
VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(bus);
DeviceState *proxy = DEVICE(BUS(bus)->parent);
VirtIODevice *vdev;
int n, r;
if (!k->ioeventfd_started || !k->ioeventfd_started(proxy)) {
return;
}
vdev = virtio_bus_get_device(bus);
for (n = 0; n < VIRTIO_QUEUE_MAX; n++) {
if (!virtio_queue_get_num(vdev, n)) {
continue;
}
r = set_host_notifier_internal(proxy, bus, n, false, false);
assert(r >= 0);
}
k->ioeventfd_set_started(proxy, false, false);
}
void virtio_bus_start_ioeventfd(VirtioBusState *bus)
{
VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(bus);
DeviceState *proxy = DEVICE(BUS(bus)->parent);
VirtIODevice *vdev;
int n, r;
if (!k->ioeventfd_started || k->ioeventfd_started(proxy)) {
return;
}
if (k->ioeventfd_disabled(proxy)) {
return;
}
vdev = virtio_bus_get_device(bus);
for (n = 0; n < VIRTIO_QUEUE_MAX; n++) {
if (!virtio_queue_get_num(vdev, n)) {
continue;
}
r = set_host_notifier_internal(proxy, bus, n, true, true);
if (r < 0) {
goto assign_error;
}
}
k->ioeventfd_set_started(proxy, true, false);
return;
assign_error:
while (--n >= 0) {
if (!virtio_queue_get_num(vdev, n)) {
continue;
}
r = set_host_notifier_internal(proxy, bus, n, false, false);
assert(r >= 0);
}
k->ioeventfd_set_started(proxy, false, true);
error_report("%s: failed. Fallback to userspace (slower).", __func__);
}
