[PATCH v13 20/42] virtio_ring: packed: extract the logic of vring init

[Jason Wang]

在 2022/7/26 15:22, Xuan Zhuo 写道:
> Separate the logic of initializing vring, and subsequent patches will
> call it separately.
>
> This function completes the variable initialization of packed 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 | 28 +++++++++++++++++-----------
>   1 file changed, 17 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> index 32590d763c3b..fc4e3db9f93b 100644
> --- a/drivers/virtio/virtio_ring.c
> +++ b/drivers/virtio/virtio_ring.c
> @@ -1935,6 +1935,22 @@ static int vring_alloc_state_extra_packed(struct vring_virtqueue_packed *vring_p
>   	return -ENOMEM;
>   }
>   
> +static void virtqueue_vring_init_packed(struct vring_virtqueue_packed *vring_packed,
> +					bool callback)
> +{
> +	vring_packed->next_avail_idx = 0;
> +	vring_packed->avail_wrap_counter = 1;
> +	vring_packed->event_flags_shadow = 0;
> +	vring_packed->avail_used_flags = 1 << VRING_PACKED_DESC_F_AVAIL;
> +
> +	/* No callback?  Tell other side not to bother us. */
> +	if (!callback) {
> +		vring_packed->event_flags_shadow = VRING_PACKED_EVENT_FLAG_DISABLE;
> +		vring_packed->vring.driver->flags =
> +			cpu_to_le16(vring_packed->event_flags_shadow);
> +	}
> +}
> +
>   static struct virtqueue *vring_create_virtqueue_packed(
>   	unsigned int index,
>   	unsigned int num,
> @@ -1984,11 +2000,6 @@ static struct virtqueue *vring_create_virtqueue_packed(
>   
>   	vq->packed.vring = vring_packed.vring;
>   
> -	vq->packed.next_avail_idx = 0;
> -	vq->packed.avail_wrap_counter = 1;
> -	vq->packed.event_flags_shadow = 0;
> -	vq->packed.avail_used_flags = 1 << VRING_PACKED_DESC_F_AVAIL;
> -
>   	err = vring_alloc_state_extra_packed(&vring_packed);
>   	if (err)
>   		goto err_state_extra;
> @@ -1996,12 +2007,7 @@ static struct virtqueue *vring_create_virtqueue_packed(
>   	vq->packed.desc_state = vring_packed.desc_state;
>   	vq->packed.desc_extra = vring_packed.desc_extra;
>   
> -	/* No callback?  Tell other side not to bother us. */
> -	if (!callback) {
> -		vq->packed.event_flags_shadow = VRING_PACKED_EVENT_FLAG_DISABLE;
> -		vq->packed.vring.driver->flags =
> -			cpu_to_le16(vq->packed.event_flags_shadow);
> -	}
> +	virtqueue_vring_init_packed(&vring_packed, !!callback);
>   
>   	virtqueue_init(vq, num);
>