[PATCH v11 11/40] virtio_ring: split: extract the logic of vring init

[Jason Wang]

在 2022/6/29 14:56, Xuan Zhuo 写道:
> Separate the logic of initializing vring, and subsequent patches will
> call it separately.
>
> This function completes the variable initialization of split vring. It
> together with the logic of atatch constitutes the initialization of
> vring.
>
> Signed-off-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com>


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


> ---
>   drivers/virtio/virtio_ring.c | 30 +++++++++++++++++++-----------
>   1 file changed, 19 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> index 9025bd373d3b..35540daaa1e7 100644
> --- a/drivers/virtio/virtio_ring.c
> +++ b/drivers/virtio/virtio_ring.c
> @@ -940,6 +940,24 @@ static void *virtqueue_detach_unused_buf_split(struct virtqueue *_vq)
>   	return NULL;
>   }
>   
> +static void virtqueue_vring_init_split(struct vring_virtqueue *vq)
> +{
> +	struct virtio_device *vdev;
> +
> +	vdev = vq->vq.vdev;
> +
> +	vq->split.avail_flags_shadow = 0;
> +	vq->split.avail_idx_shadow = 0;
> +
> +	/* No callback?  Tell other side not to bother us. */
> +	if (!vq->vq.callback) {
> +		vq->split.avail_flags_shadow |= VRING_AVAIL_F_NO_INTERRUPT;
> +		if (!vq->event)
> +			vq->split.vring.avail->flags = cpu_to_virtio16(vdev,
> +					vq->split.avail_flags_shadow);
> +	}
> +}
> +
>   static void virtqueue_vring_attach_split(struct vring_virtqueue *vq,
>   					 struct vring_virtqueue_split *vring)
>   {
> @@ -2299,17 +2317,6 @@ struct virtqueue *__vring_new_virtqueue(unsigned int index,
>   	vq->indirect = virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC) &&
>   		!context;
>   
> -	vq->split.avail_flags_shadow = 0;
> -	vq->split.avail_idx_shadow = 0;
> -
> -	/* No callback?  Tell other side not to bother us. */
> -	if (!callback) {
> -		vq->split.avail_flags_shadow |= VRING_AVAIL_F_NO_INTERRUPT;
> -		if (!vq->event)
> -			vq->split.vring.avail->flags = cpu_to_virtio16(vdev,
> -					vq->split.avail_flags_shadow);
> -	}
> -
>   	vring.vring = _vring;
>   
>   	err = vring_alloc_state_extra_split(&vring);
> @@ -2320,6 +2327,7 @@ struct virtqueue *__vring_new_virtqueue(unsigned int index,
>   
>   	virtqueue_init(vq, vring.vring.num);
>   	virtqueue_vring_attach_split(vq, &vring);
> +	virtqueue_vring_init_split(vq);
>   
>   	spin_lock(&vdev->vqs_list_lock);
>   	list_add_tail(&vq->vq.list, &vdev->vqs);