Re: [RFC PATCH 3/8] virtio-pci: save/restore config space across S4

["Michael S. Tsirkin" <mst@redhat.com>]

On Thu, Jul 28, 2011 at 08:05:08PM +0530, Amit Shah wrote:
> The virtio config space doesn't get saved across hibernation; we save it
> locally and update it after restore.
> 
> Signed-off-by: Amit Shah <amit.shah@redhat.com>
> ---
>  drivers/virtio/virtio_pci.c |    6 ++++++
>  1 files changed, 6 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
> index 579681f..9c37561 100644
> --- a/drivers/virtio/virtio_pci.c
> +++ b/drivers/virtio/virtio_pci.c
> @@ -56,6 +56,10 @@ struct virtio_pci_device
>  	unsigned msix_vectors;
>  	/* Vectors allocated, excluding per-vq vectors if any */
>  	unsigned msix_used_vectors;
> +
> +	/* Status saved during hibernate/restore */
> +	u8 saved_status;
> +
>  	/* Whether we have vector per vq */
>  	bool per_vq_vectors;
>  };
> @@ -713,6 +717,7 @@ static int virtio_pci_freeze(struct device *dev)
>  	drv = container_of(vp_dev->vdev.dev.driver,
>  			   struct virtio_driver, driver);
>  
> +	vp_dev->saved_status = vp_get_status(&vp_dev->vdev);
>  	if (drv && drv->freeze)
>  		return drv->freeze(&vp_dev->vdev);
>  
> @@ -728,6 +733,7 @@ static int virtio_pci_restore(struct device *dev)
>  	drv = container_of(vp_dev->vdev.dev.driver,
>  			   struct virtio_driver, driver);
>  
> +	vp_set_status(&vp_dev->vdev, vp_dev->saved_status);
>  	if (drv && drv->restore)
>  		return drv->restore(&vp_dev->vdev);

Yes, this looks wrong. Status would typically be DRIVER_OK,
and it needs to be set after vq setup.
It also needs to match current state I think:
e.g. if restore failed we want to set it to FAILED.
So why not do it more or less the way probe does it?


> -- 
> 1.7.6