[PATCH v9 10/32] virtio_ring: split: introduce virtqueue_reinit_split()

[Jason Wang]

在 2022/4/6 上午11:43, Xuan Zhuo 写道:
> Introduce a function to initialize vq without allocating new ring,
> desc_state, desc_extra.
>
> Subsequent patches will call this function after reset vq to
> reinitialize vq.
>
> Signed-off-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com>


Acked-by: Jason Wang <jasowang at redhat.com>


> ---
>   drivers/virtio/virtio_ring.c | 19 +++++++++++++++++++
>   1 file changed, 19 insertions(+)
>
> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> index 874f878087a3..3dc6ace2ba7a 100644
> --- a/drivers/virtio/virtio_ring.c
> +++ b/drivers/virtio/virtio_ring.c
> @@ -953,6 +953,25 @@ static void vring_virtqueue_init_split(struct vring_virtqueue *vq,
>   	vq->free_head = 0;
>   }
>   
> +static void virtqueue_reinit_split(struct vring_virtqueue *vq)
> +{
> +	struct virtio_device *vdev = vq->vq.vdev;
> +	int size, i;
> +
> +	memset(vq->split.vring.desc, 0, vq->split.queue_size_in_bytes);
> +
> +	size = sizeof(struct vring_desc_state_split) * vq->split.vring.num;
> +	memset(vq->split.desc_state, 0, size);
> +
> +	size = sizeof(struct vring_desc_extra) * vq->split.vring.num;
> +	memset(vq->split.desc_extra, 0, size);
> +
> +	for (i = 0; i < vq->split.vring.num - 1; i++)
> +		vq->split.desc_extra[i].next = i + 1;
> +
> +	vring_virtqueue_init_split(vq, vdev, true);
> +}
> +
>   static void vring_virtqueue_attach_split(struct vring_virtqueue *vq,
>   					 struct vring vring,
>   					 struct vring_desc_state_split *desc_state,