[Qemu-devel] [RFC 4/6] virtio/migration: Add VMStateDescription to VirtioDeviceClass

["Dr. David Alan Gilbert (git)" <dgilbert@redhat.com>]

From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>

Provide a vmsd pointer for VirtIO devices to use instead of the
load/save methods.

We'll eventually kill off the load/save methods.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
 hw/virtio/virtio.c         | 11 +++++++++++
 include/hw/virtio/virtio.h |  2 ++
 2 files changed, 13 insertions(+)

diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index 15ee3a7..3a4fa93 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -1470,6 +1470,10 @@ void virtio_save(VirtIODevice *vdev, QEMUFile *f)
         vdc->save(vdev, f);
     }
 
+    if (vdc->vmsd) {
+        vmstate_save_state(f, vdc->vmsd, vdev, NULL);
+    }
+
     /* Subsections */
     vmstate_save_state(f, &vmstate_virtio, vdev, NULL);
 }
@@ -1601,6 +1605,13 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id)
         }
     }
 
+    if (vdc->vmsd) {
+        ret = vmstate_load_state(f, vdc->vmsd, vdev, version_id);
+        if (ret) {
+            return ret;
+        }
+    }
+
     /* Subsections */
     ret = vmstate_load_state(f, &vmstate_virtio, vdev, 1);
     if (ret) {
diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h
index d2490c1..fd386ac 100644
--- a/include/hw/virtio/virtio.h
+++ b/include/hw/virtio/virtio.h
@@ -124,8 +124,10 @@ typedef struct VirtioDeviceClass {
      * must mask in frontend instead.
      */
     void (*guest_notifier_mask)(VirtIODevice *vdev, int n, bool mask);
+    /* Saving and loading of a device; use *either* save/load OR vmsd */
     void (*save)(VirtIODevice *vdev, QEMUFile *f);
     int (*load)(VirtIODevice *vdev, QEMUFile *f, int version_id);
+    const VMStateDescription *vmsd;
 } VirtioDeviceClass;
 
 void virtio_instance_init_common(Object *proxy_obj, void *data,
-- 
2.7.4