Re: [PATCH v2 09/24] vhost: introduce vhost_dev_virtqueue_stop()

[Jason Wang]

在 2022/8/16 09:06, Kangjie Xu 写道:
> Introduce vhost_dev_virtqueue_stop(), which can ummap the
> vrings and the desc of it.
>
> Signed-off-by: Kangjie Xu <kangjie.xu@linux.alibaba.com>
> Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
> ---
>   hw/virtio/vhost.c         | 9 +++++++++
>   include/hw/virtio/vhost.h | 3 +++
>   2 files changed, 12 insertions(+)
>
> diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
> index e467dfc7bc..1bca9ff48d 100644
> --- a/hw/virtio/vhost.c
> +++ b/hw/virtio/vhost.c
> @@ -1904,3 +1904,12 @@ int vhost_net_set_backend(struct vhost_dev *hdev,
>   
>       return -ENOSYS;
>   }
> +
> +void vhost_dev_virtqueue_stop(struct vhost_dev *hdev, VirtIODevice *vdev,
> +                              int idx)
> +{
> +    vhost_virtqueue_unmap(hdev,
> +                          vdev,
> +                          hdev->vqs + idx,
> +                          idx);


So I think the unmap is not sufficient, we need backend specific 
support. E.g for vhost kernel, need a SET_BACKEND here?

Thanks


> +}
> diff --git a/include/hw/virtio/vhost.h b/include/hw/virtio/vhost.h
> index a346f23d13..574888440c 100644
> --- a/include/hw/virtio/vhost.h
> +++ b/include/hw/virtio/vhost.h
> @@ -288,4 +288,7 @@ int vhost_dev_set_inflight(struct vhost_dev *dev,
>                              struct vhost_inflight *inflight);
>   int vhost_dev_get_inflight(struct vhost_dev *dev, uint16_t queue_size,
>                              struct vhost_inflight *inflight);
> +
> +void vhost_dev_virtqueue_stop(struct vhost_dev *hdev, VirtIODevice *vdev,
> +                              int idx);
>   #endif