virtio: introduce device specific migration calls

In order to migrate virtio subsections, they should be streamed after
the device itself. We need the device specific code to be called from
the common migration code to achieve this. This patch introduces load
and save methods for this purpose.

Suggested-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Reviewed-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

1 files changed, 12 insertions, 1 deletions

diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index c1d538c5f3..7f9ac5e0b9 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -843,6 +843,7 @@ void virtio_save(VirtIODevice *vdev, QEMUFile *f)
 {
     BusState *qbus = qdev_get_parent_bus(DEVICE(vdev));
     VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
+    VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev);
     int i;
 
     if (k->save_config) {
@@ -877,6 +878,10 @@ void virtio_save(VirtIODevice *vdev, QEMUFile *f)
             k->save_queue(qbus->parent, i, f);
         }
     }
+
+    if (vdc->save != NULL) {
+        vdc->save(vdev, f);
+    }
 }
 
 int virtio_set_features(VirtIODevice *vdev, uint32_t val)
@@ -895,7 +900,7 @@ int virtio_set_features(VirtIODevice *vdev, uint32_t val)
     return bad ? -1 : 0;
 }
 
-int virtio_load(VirtIODevice *vdev, QEMUFile *f)
+int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id)
 {
     int i, ret;
     int32_t config_len;
@@ -904,6 +909,7 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f)
     uint32_t supported_features;
     BusState *qbus = qdev_get_parent_bus(DEVICE(vdev));
     VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
+    VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev);
 
     if (k->load_config) {
         ret = k->load_config(qbus->parent, f);
@@ -983,6 +989,11 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f)
     }
 
     virtio_notify_vector(vdev, VIRTIO_NO_VECTOR);
+
+    if (vdc->load != NULL) {
+        return vdc->load(vdev, f, version_id);
+    }
+
     return 0;
 }