Re: [PATCH RFC v6 10/11] vhost/vsock: switch to the buf API

[Stefano Garzarella]

On Mon, Jun 08, 2020 at 08:53:13AM -0400, Michael S. Tsirkin wrote:
> A straight-forward conversion.
> 
> Signed-off-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
> ---
>  drivers/vhost/vsock.c | 30 ++++++++++++++++++------------
>  1 file changed, 18 insertions(+), 12 deletions(-)

I ran the vsock tests again with this new series and everything seems
to go well:

Reviewed-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>
Tested-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>

Thanks,
Stefano

> 
> diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c
> index a483cec31d5c..61c6d3dd2ae3 100644
> --- a/drivers/vhost/vsock.c
> +++ b/drivers/vhost/vsock.c
> @@ -103,7 +103,8 @@ vhost_transport_do_send_pkt(struct vhost_vsock *vsock,
>  		unsigned out, in;
>  		size_t nbytes;
>  		size_t iov_len, payload_len;
> -		int head;
> +		struct vhost_buf buf;
> +		int ret;
>  
>  		spin_lock_bh(&vsock->send_pkt_list_lock);
>  		if (list_empty(&vsock->send_pkt_list)) {
> @@ -117,16 +118,17 @@ vhost_transport_do_send_pkt(struct vhost_vsock *vsock,
>  		list_del_init(&pkt->list);
>  		spin_unlock_bh(&vsock->send_pkt_list_lock);
>  
> -		head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov),
> -					 &out, &in, NULL, NULL);
> -		if (head < 0) {
> +		ret = vhost_get_avail_buf(vq, &buf,
> +					  vq->iov, ARRAY_SIZE(vq->iov),
> +					  &out, &in, NULL, NULL);
> +		if (ret < 0) {
>  			spin_lock_bh(&vsock->send_pkt_list_lock);
>  			list_add(&pkt->list, &vsock->send_pkt_list);
>  			spin_unlock_bh(&vsock->send_pkt_list_lock);
>  			break;
>  		}
>  
> -		if (head == vq->num) {
> +		if (!ret) {
>  			spin_lock_bh(&vsock->send_pkt_list_lock);
>  			list_add(&pkt->list, &vsock->send_pkt_list);
>  			spin_unlock_bh(&vsock->send_pkt_list_lock);
> @@ -186,7 +188,8 @@ vhost_transport_do_send_pkt(struct vhost_vsock *vsock,
>  		 */
>  		virtio_transport_deliver_tap_pkt(pkt);
>  
> -		vhost_add_used(vq, head, sizeof(pkt->hdr) + payload_len);
> +		buf.in_len = sizeof(pkt->hdr) + payload_len;
> +		vhost_put_used_buf(vq, &buf);
>  		added = true;
>  
>  		pkt->off += payload_len;
> @@ -440,7 +443,8 @@ static void vhost_vsock_handle_tx_kick(struct vhost_work *work)
>  	struct vhost_vsock *vsock = container_of(vq->dev, struct vhost_vsock,
>  						 dev);
>  	struct virtio_vsock_pkt *pkt;
> -	int head, pkts = 0, total_len = 0;
> +	int ret, pkts = 0, total_len = 0;
> +	struct vhost_buf buf;
>  	unsigned int out, in;
>  	bool added = false;
>  
> @@ -461,12 +465,13 @@ static void vhost_vsock_handle_tx_kick(struct vhost_work *work)
>  			goto no_more_replies;
>  		}
>  
> -		head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov),
> -					 &out, &in, NULL, NULL);
> -		if (head < 0)
> +		ret = vhost_get_avail_buf(vq, &buf,
> +					  vq->iov, ARRAY_SIZE(vq->iov),
> +					  &out, &in, NULL, NULL);
> +		if (ret < 0)
>  			break;
>  
> -		if (head == vq->num) {
> +		if (!ret) {
>  			if (unlikely(vhost_enable_notify(&vsock->dev, vq))) {
>  				vhost_disable_notify(&vsock->dev, vq);
>  				continue;
> @@ -494,7 +499,8 @@ static void vhost_vsock_handle_tx_kick(struct vhost_work *work)
>  			virtio_transport_free_pkt(pkt);
>  
>  		len += sizeof(pkt->hdr);
> -		vhost_add_used(vq, head, len);
> +		buf.in_len = len;
> +		vhost_put_used_buf(vq, &buf);
>  		total_len += len;
>  		added = true;
>  	} while(likely(!vhost_exceeds_weight(vq, ++pkts, total_len)));
> -- 
> MST
>