Re: [PATCH 09/31] vhost-vdpa: Take into account SVQ in vhost_vdpa_set_vring_call

[Jason Wang <jasowang@redhat.com>]

在 2022/1/22 上午4:27, Eugenio Pérez 写道:
> Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
> ---
>   hw/virtio/vhost-vdpa.c | 20 ++++++++++++++++++--
>   1 file changed, 18 insertions(+), 2 deletions(-)
>
> diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
> index 18de14f0fb..029f98feee 100644
> --- a/hw/virtio/vhost-vdpa.c
> +++ b/hw/virtio/vhost-vdpa.c
> @@ -687,13 +687,29 @@ static int vhost_vdpa_set_vring_kick(struct vhost_dev *dev,
>       }
>   }
>   
> -static int vhost_vdpa_set_vring_call(struct vhost_dev *dev,
> -                                       struct vhost_vring_file *file)
> +static int vhost_vdpa_set_vring_dev_call(struct vhost_dev *dev,
> +                                         struct vhost_vring_file *file)
>   {
>       trace_vhost_vdpa_set_vring_call(dev, file->index, file->fd);
>       return vhost_vdpa_call(dev, VHOST_SET_VRING_CALL, file);
>   }
>   
> +static int vhost_vdpa_set_vring_call(struct vhost_dev *dev,
> +                                     struct vhost_vring_file *file)
> +{
> +    struct vhost_vdpa *v = dev->opaque;
> +
> +    if (v->shadow_vqs_enabled) {
> +        int vdpa_idx = vhost_vdpa_get_vq_index(dev, file->index);
> +        VhostShadowVirtqueue *svq = g_ptr_array_index(v->shadow_vqs, vdpa_idx);
> +
> +        vhost_svq_set_guest_call_notifier(svq, file->fd);


Two questions here (had similar questions for vring kick):

1) Any reason that we setup the eventfd for vhost-vdpa in 
vhost_vdpa_svq_setup() not here?

2) The call could be disabled by using -1 as the fd, I don't see any 
code to deal with that.

Thanks


> +        return 0;
> +    } else {
> +        return vhost_vdpa_set_vring_dev_call(dev, file);
> +    }
> +}
> +
>   /**
>    * Set shadow virtqueue descriptors to the device
>    *