Re: [Qemu-devel] [PATCH 00/15] qdev: make reset semantics more clear and consistent, reset qbuses under virtio devices

[Paolo Bonzini <pbonzini@redhat.com>]

Il 17/12/2012 22:43, Michael S. Tsirkin ha scritto:
> On Mon, Dec 17, 2012 at 05:24:35PM +0100, Paolo Bonzini wrote:
>> After discussion with mst on the topic of resetting virtio devices,
>> here is a series that hopefully clarifies the semantics of bus and
>> device resets.
>>
>> After this series, there are two kinds of resets:
> 
> So just to clarify, what I proposed was this
> (on top of my type safety patch). Then
> all transports can call virtio_config_reset
> when appropriate (e.g. when PA is set to 0).
> 
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> 
> diff --git a/hw/virtio.c b/hw/virtio.c
> index f40a8c5..e65d7c8 100644
> --- a/hw/virtio.c
> +++ b/hw/virtio.c
> @@ -554,6 +554,14 @@ void virtio_reset(void *opaque)
>      }
>  }
>  
> +/* Device-specific reset through virtio config space.
> + * Reset virtio config and backend child devices if any.
> + */
> +void virtio_config_reset(VirtIODevice *vdev)
> +{
> +    qdev_reset_all(vdev->binding_opaque);
> +}

Yes, I had understood.  As I said, this is the wrong direction.
Resetting happens from vdev->binding_opaque, it can just do
qdev_reset_all(myself).

Paolo

>  uint32_t virtio_config_readb(VirtIODevice *vdev, uint32_t addr)
>  {
>      uint8_t val;
> diff --git a/hw/virtio.h b/hw/virtio.h
> index 7c17f7b..e2e57a4 100644
> --- a/hw/virtio.h
> +++ b/hw/virtio.h
> @@ -187,11 +187,12 @@ uint16_t virtio_queue_vector(VirtIODevice *vdev, int n);
>  void virtio_queue_set_vector(VirtIODevice *vdev, int n, uint16_t vector);
>  void virtio_set_status(VirtIODevice *vdev, uint8_t val);
>  void virtio_reset(void *opaque);
> +void virtio_config_reset(VirtIODevice *vdev);
>  void virtio_update_irq(VirtIODevice *vdev);
>  int virtio_set_features(VirtIODevice *vdev, uint32_t val);
>  
>  void virtio_bind_device(VirtIODevice *vdev, const VirtIOBindings *binding,
>                          DeviceState *opaque);
>  
>  /* Base devices.  */
>  typedef struct VirtIOBlkConf VirtIOBlkConf;
> 
>