virtio: prepare change VMSTATE_VIRTIO_DEVICE macro

In most cases the functions passed to VMSTATE_VIRTIO_DEVICE
only call the virtio_load and virtio_save wrappers. Some include some
pre- and post- massaging too. The massaging is better expressed
as such in the VMStateDescription.

Let us prepare for changing the semantic of the VMSTATE_VIRTIO_DEVICE
macro so that it is more similar to the other VMSTATE_*_DEVICE macros
in a sense that it is a field definition.

The preprocessor conditionals are going to be removed as soon as
every usage is converted to the new semantic.
Signed-off-by: NHalil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

hw/virtio/virtio.c

@@ -1645,6 +1645,27 @@ void virtio_vmstate_save(QEMUFile *f, void *opaque, size_t size)
     virtio_save(VIRTIO_DEVICE(opaque), f);
 }
 
+/* A wrapper for use as a VMState .put function */
+static void virtio_device_put(QEMUFile *f, void *opaque, size_t size)
+{
+    virtio_save(VIRTIO_DEVICE(opaque), f);
+}
+
+/* A wrapper for use as a VMState .get function */
+static int virtio_device_get(QEMUFile *f, void *opaque, size_t size)
+{
+    VirtIODevice *vdev = VIRTIO_DEVICE(opaque);
+    DeviceClass *dc = DEVICE_CLASS(VIRTIO_DEVICE_GET_CLASS(vdev));
+
+    return virtio_load(vdev, f, dc->vmsd->version_id);
+}
+
+const VMStateInfo  virtio_vmstate_info = {
+    .name = "virtio",
+    .get = virtio_device_get,
+    .put = virtio_device_put,
+};
+
 static int virtio_set_features_nocheck(VirtIODevice *vdev, uint64_t val)
 {
     VirtioDeviceClass *k = VIRTIO_DEVICE_GET_CLASS(vdev);

include/hw/virtio/virtio.h

@@ -179,6 +179,20 @@ void virtio_notify(VirtIODevice *vdev, VirtQueue *vq);
 void virtio_save(VirtIODevice *vdev, QEMUFile *f);
 void virtio_vmstate_save(QEMUFile *f, void *opaque, size_t size);
 
+extern const VMStateInfo virtio_vmstate_info;
+
+#ifdef VMSTATE_VIRTIO_DEVICE_USE_NEW
+
+#define VMSTATE_VIRTIO_DEVICE \
+    {                                         \
+        .name = "virtio",                     \
+        .info = &virtio_vmstate_info,         \
+        .flags = VMS_SINGLE,                  \
+    }
+
+#else
+/* TODO remove conditional as soon as all users are converted */
+
 #define VMSTATE_VIRTIO_DEVICE(devname, v, getf, putf) \
     static const VMStateDescription vmstate_virtio_ ## devname = { \
         .name = "virtio-" #devname ,          \
@@ -198,6 +212,8 @@ void virtio_vmstate_save(QEMUFile *f, void *opaque, size_t size);
         }                                     \
     }
 
+#endif
+
 int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id);
 
 void virtio_notify_config(VirtIODevice *vdev);