@@ -158,6 +158,13 @@ typedef struct VirtioDeviceClass {
void (*save)(VirtIODevice *vdev, QEMUFile *f);
int (*load)(VirtIODevice *vdev, QEMUFile *f, int version_id);
const VMStateDescription *vmsd;
+
+ /* Called when the device should start/stop running because the guest was
+ * resumed/paused. Note that this takes VIRTIO_CONFIG_S_DRIVER_OK into
+ * account so running is true iff the guest is resumed and the guest driver
+ * has already indicated it is ready.
+ */
+ void (*vmstate_change)(VirtIODevice *vdev, bool running);
} VirtioDeviceClass;
void virtio_instance_init_common(Object *proxy_obj, void *data,
@@ -2291,6 +2291,7 @@ static void virtio_vmstate_change(void *opaque, int running, RunState state)
VirtIODevice *vdev = opaque;
BusState *qbus = qdev_get_parent_bus(DEVICE(vdev));
VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
+ VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev);
bool backend_run = running && vdev->started;
vdev->vm_running = running;
@@ -2298,10 +2299,18 @@ static void virtio_vmstate_change(void *opaque, int running, RunState state)
virtio_set_status(vdev, vdev->status);
}
+ if (!backend_run && vdc->vmstate_change) {
+ vdc->vmstate_change(vdev, backend_run);
+ }
+
if (k->vmstate_change) {
k->vmstate_change(qbus->parent, backend_run);
}
+ if (backend_run && vdc->vmstate_change) {
+ vdc->vmstate_change(vdev, backend_run);
+ }
+
if (!backend_run) {
virtio_set_status(vdev, vdev->status);
}
The core virtio code invokes ->set_status() followed by ->ioeventfd_start() when the guest resumes execution. Both of these functions are also called in other cases unrelated to vm change state. This patch introduces ->vmstate_change() so that devices can act on guest pause/resume. The existing qemu_add_vm_change_state_handler() API isn't usable by virtio devices since the ordering between vm change state handlers is undefined. The new ->vmstate_change() callback is always invoked after ->set_status() and ->ioeventfd_start() when resuming a guest. A later patch makes use of this new callback. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> --- include/hw/virtio/virtio.h | 7 +++++++ hw/virtio/virtio.c | 9 +++++++++ 2 files changed, 16 insertions(+)