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virtio vmstatification

PATCH In review Dr. David Alan Gilbert (git) 2 participants 5 messages Oct 27, 2016 – Nov 2, 2016

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Dr. David Alan Gilbert (git)

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cover virtio vmstatification

From: "Dr. David Alan Gilbert" <[email protected]>

Hi,
This contains part of a series I previously posted as an RFC;
it contains just the code to add the vmsd hook to virtio and the simple case for balloon. The networking code will have to wait until my VMSTATE_WITH_TMP macros go in and there's some other stuff I need to figure out for the other devices. However, it seems right to get the hook in for anyone else who wants to do stuff.

Since the RFC I've added an assert to ensure that you can only have either the new vmsd hook or the old ->load/save methods.

Dave

Dr. David Alan Gilbert (2):
virtio/migration: Add VMStateDescription to VirtioDeviceClass virtio/migration: Migrate balloon to VMState

 hw/virtio/virtio-balloon.c | 31 +++++++++++++++----------------
 hw/virtio/virtio.c         | 14 ++++++++++++++
 include/hw/virtio/virtio.h |  4 ++++
 3 files changed, 33 insertions(+), 16 deletions(-)
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2.9.3
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#1 lore raw

PATCH 1/2 virtio/migration: Add VMStateDescription to VirtioDeviceClass

From: "Dr. David Alan Gilbert" <[email protected]>

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 <[email protected]>
---
 hw/virtio/virtio.c         | 14 ++++++++++++++
 include/hw/virtio/virtio.h |  4 ++++
 2 files changed, 18 insertions(+)
hw/virtio/virtio.c +14 -0
index d48d1a9..3e318e4 100644
@@ -1635,6 +1635,10 @@ 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);
 }

@@ -1781,6 +1785,13 @@ 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) {

@@ -2118,6 +2129,9 @@ static void virtio_device_realize(DeviceState *dev, Error **errp)
     VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(dev);
     Error *err = NULL;
 
+    /* Devices should either use vmsd or the load/save methods */
+    assert(!vdc->vmsd || !vdc->load);
+
     if (vdc->realize != NULL) {
         vdc->realize(dev, &err);
         if (err != NULL) {
include/hw/virtio/virtio.h +4 -0
index b913aac..52d4b55 100644
@@ -125,8 +125,12 @@ typedef struct VirtioDeviceClass {
      * must mask in frontend instead.
      */
     void (*guest_notifier_mask)(VirtIODevice *vdev, int n, bool mask);
+    /* Saving and loading of a device; trying to deprecate save/load
+     * use vmsd for new devices.
+     */
     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,
Signature · 1 line
2.9.3
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#3 lore raw

PATCH 2/2 virtio/migration: Migrate balloon to VMState

In reply to Dr. David Alan Gilbert (git)

From: "Dr. David Alan Gilbert" <[email protected]>

Replace the load/save with a vmsd.

Signed-off-by Dr. David Alan Gilbert <[email protected]>
---
 hw/virtio/virtio-balloon.c | 31 +++++++++++++++----------------
 1 file changed, 15 insertions(+), 16 deletions(-)
hw/virtio/virtio-balloon.c +15 -16
index 1d77028..cfba053 100644
@@ -394,21 +394,9 @@ static void virtio_balloon_to_target(void *opaque, ram_addr_t target)
     trace_virtio_balloon_to_target(target, dev->num_pages);
 }
 
-static void virtio_balloon_save_device(VirtIODevice *vdev, QEMUFile *f)
+static int virtio_balloon_post_load_device(void *opaque, int version_id)
 {
-    VirtIOBalloon *s = VIRTIO_BALLOON(vdev);
-
-    qemu_put_be32(f, s->num_pages);
-    qemu_put_be32(f, s->actual);
-}
-
-static int virtio_balloon_load_device(VirtIODevice *vdev, QEMUFile *f,
-                                      int version_id)
-{
-    VirtIOBalloon *s = VIRTIO_BALLOON(vdev);
-
-    s->num_pages = qemu_get_be32(f);
-    s->actual = qemu_get_be32(f);
+    VirtIOBalloon *s = VIRTIO_BALLOON(opaque);
 
     if (balloon_stats_enabled(s)) {
         balloon_stats_change_timer(s, s->stats_poll_interval);

@@ -416,6 +404,18 @@ static int virtio_balloon_load_device(VirtIODevice *vdev, QEMUFile *f,
     return 0;
 }
 
+static const VMStateDescription vmstate_virtio_balloon_device = {
+    .name = "virtio-balloon-device",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .post_load = virtio_balloon_post_load_device,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32(num_pages, VirtIOBalloon),
+        VMSTATE_UINT32(actual, VirtIOBalloon),
+        VMSTATE_END_OF_LIST()
+    },
+};
+
 static void virtio_balloon_device_realize(DeviceState *dev, Error **errp)
 {
     VirtIODevice *vdev = VIRTIO_DEVICE(dev);

@@ -517,9 +517,8 @@ static void virtio_balloon_class_init(ObjectClass *klass, void *data)
     vdc->get_config = virtio_balloon_get_config;
     vdc->set_config = virtio_balloon_set_config;
     vdc->get_features = virtio_balloon_get_features;
-    vdc->save = virtio_balloon_save_device;
-    vdc->load = virtio_balloon_load_device;
     vdc->set_status = virtio_balloon_set_status;
+    vdc->vmsd = &vmstate_virtio_balloon_device;
 }
 
 static const TypeInfo virtio_balloon_info = {
Signature · 1 line
2.9.3