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[20/30] s390x: convert virtio-ccw to hotplug handler API

Message ID 1411559299-19042-21-git-send-email-imammedo@redhat.com
State New
Headers show

Commit Message

Igor Mammedov Sept. 24, 2014, 11:48 a.m. UTC 
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
---
 hw/s390x/virtio-ccw.c | 24 ++++++++++++++++--------
 1 file changed, 16 insertions(+), 8 deletions(-)

Comments

Cornelia Huck Sept. 25, 2014, 11:08 a.m. UTC | #1 
On Wed, 24 Sep 2014 11:48:09 +0000
Igor Mammedov <imammedo@redhat.com> wrote:

> Signed-off-by: Igor Mammedov <imammedo@redhat.com>
> ---
>  hw/s390x/virtio-ccw.c | 24 ++++++++++++++++--------
>  1 file changed, 16 insertions(+), 8 deletions(-)

Well, I think I now see what's going on here. More below...


> @@ -1620,13 +1620,13 @@ static Property virtio_ccw_properties[] = {
>  static void virtio_ccw_device_class_init(ObjectClass *klass, void *data)
>  {
>      DeviceClass *dc = DEVICE_CLASS(klass);
> +    HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass);
> 
>      dc->props = virtio_ccw_properties;
>      dc->init = virtio_ccw_busdev_init;
>      dc->exit = virtio_ccw_busdev_exit;
> -    dc->unplug = virtio_ccw_busdev_unplug;

Before, this callback was invoked when a device of the virtio-ccw class
was unplugged.

>      dc->bus_type = TYPE_VIRTUAL_CSS_BUS;
> -
> +    hc->unplug = virtio_ccw_busdev_unplug;

Now, this callback is supposed to be invoked instead. However, the
unplugging code invokes the callback for the _parent bus_, which
means...

>  }
> 
>  static const TypeInfo virtio_ccw_device_info = {

>  static void virtual_css_bridge_class_init(ObjectClass *klass, void *data)
>  {
>      SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
> +    HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass);
> 
>      k->init = virtual_css_bridge_init;
> +    hc->unplug = qdev_simple_device_unplug_cb;

...we're invoking this one, as the parent bus for virtio-ccw devices is
the virtual-css bus.

If I change this callback to the virtio-ccw one, everything works as
expected.

>  }

So, to summarize, what happened before was

bridge device              <--- (simple unplug invoked for dev)
 -> virtual bus
  -> virtio proxy device   <--- virtio unplug invoked for dev
   -> virtio bus
    -> virtio device

which your patch changed to

bridge device
 -> virtual bus            <--- simple unplug invoked for virtio proxy dev
  -> virtio proxy device
   -> virtio bus           <--- (virtio unplug invoked for virtio dev)
    -> virtio device

Am I understanding this correctly?
diff mbox

Patch

diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c
index 33a1d86..ccd6046 100644
--- a/hw/s390x/virtio-ccw.c
+++ b/hw/s390x/virtio-ccw.c
@@ -230,7 +230,7 @@  VirtualCssBus *virtual_css_bus_init(void)
     cbus = VIRTUAL_CSS_BUS(bus);
 
     /* Enable hotplugging */
-    bus->allow_hotplug = 1;
+    qbus_set_hotplug_handler(bus, dev, &error_abort);
 
     return cbus;
 }
@@ -1590,7 +1590,8 @@  static int virtio_ccw_busdev_exit(DeviceState *dev)
     return _info->exit(_dev);
 }
 
-static int virtio_ccw_busdev_unplug(DeviceState *dev)
+static void virtio_ccw_busdev_unplug(HotplugHandler *hotplug_dev,
+                                     DeviceState *dev, Error **errp)
 {
     VirtioCcwDevice *_dev = (VirtioCcwDevice *)dev;
     SubchDev *sch = _dev->sch;
@@ -1609,7 +1610,6 @@  static int virtio_ccw_busdev_unplug(DeviceState *dev)
     css_generate_sch_crws(sch->cssid, sch->ssid, sch->schid, 1, 0);
 
     object_unparent(OBJECT(dev));
-    return 0;
 }
 
 static Property virtio_ccw_properties[] = {
@@ -1620,13 +1620,13 @@  static Property virtio_ccw_properties[] = {
 static void virtio_ccw_device_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
+    HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass);
 
     dc->props = virtio_ccw_properties;
     dc->init = virtio_ccw_busdev_init;
     dc->exit = virtio_ccw_busdev_exit;
-    dc->unplug = virtio_ccw_busdev_unplug;
     dc->bus_type = TYPE_VIRTUAL_CSS_BUS;
-
+    hc->unplug = virtio_ccw_busdev_unplug;
 }
 
 static const TypeInfo virtio_ccw_device_info = {
@@ -1636,6 +1636,10 @@  static const TypeInfo virtio_ccw_device_info = {
     .class_init = virtio_ccw_device_class_init,
     .class_size = sizeof(VirtIOCCWDeviceClass),
     .abstract = true,
+    .interfaces = (InterfaceInfo[]) {
+        { TYPE_HOTPLUG_HANDLER },
+        { }
+    }
 };
 
 /***************** Virtual-css Bus Bridge Device ********************/
@@ -1650,8 +1654,10 @@  static int virtual_css_bridge_init(SysBusDevice *dev)
 static void virtual_css_bridge_class_init(ObjectClass *klass, void *data)
 {
     SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
+    HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass);
 
     k->init = virtual_css_bridge_init;
+    hc->unplug = qdev_simple_device_unplug_cb;
 }
 
 static const TypeInfo virtual_css_bridge_info = {
@@ -1659,6 +1665,10 @@  static const TypeInfo virtual_css_bridge_info = {
     .parent        = TYPE_SYS_BUS_DEVICE,
     .instance_size = sizeof(SysBusDevice),
     .class_init    = virtual_css_bridge_class_init,
+    .interfaces = (InterfaceInfo[]) {
+        { TYPE_HOTPLUG_HANDLER },
+        { }
+    }
 };
 
 /* virtio-ccw-bus */
@@ -1667,13 +1677,11 @@  static void virtio_ccw_bus_new(VirtioBusState *bus, size_t bus_size,
                                VirtioCcwDevice *dev)
 {
     DeviceState *qdev = DEVICE(dev);
-    BusState *qbus;
     char virtio_bus_name[] = "virtio-bus";
 
     qbus_create_inplace(bus, bus_size, TYPE_VIRTIO_CCW_BUS,
                         qdev, virtio_bus_name);
-    qbus = BUS(bus);
-    qbus->allow_hotplug = 1;
+    qbus_set_hotplug_handler(BUS(bus), qdev, &error_abort);
 }
 
 static void virtio_ccw_bus_class_init(ObjectClass *klass, void *data)