Commit d8f2835a authored by Xuan Zhuo's avatar Xuan Zhuo Committed by Jakub Kicinski
Browse files

virtio_net: introduce receive_mergeable_xdp() 



The purpose of this patch is to simplify the receive_mergeable().
Separate all the logic of XDP into a function.

Signed-off-by: default avatarXuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: default avatarJason Wang <jasowang@redhat.com>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 4cb00b13

drivers/net/virtio_net.c

+64 −41
Original line number Diff line number Diff line
@@ -1308,6 +1308,66 @@ static void *mergeable_xdp_get_buf(struct virtnet_info *vi, 
	return page_address(*page) + VIRTIO_XDP_HEADROOM;

}



static struct sk_buff *receive_mergeable_xdp(struct net_device *dev,

					     struct virtnet_info *vi,

					     struct receive_queue *rq,

					     struct bpf_prog *xdp_prog,

					     void *buf,

					     void *ctx,

					     unsigned int len,

					     unsigned int *xdp_xmit,

					     struct virtnet_rq_stats *stats)

{

	struct virtio_net_hdr_mrg_rxbuf *hdr = buf;

	int num_buf = virtio16_to_cpu(vi->vdev, hdr->num_buffers);

	struct page *page = virt_to_head_page(buf);

	int offset = buf - page_address(page);

	unsigned int xdp_frags_truesz = 0;

	struct sk_buff *head_skb;

	unsigned int frame_sz;

	struct xdp_buff xdp;

	void *data;

	u32 act;

	int err;



	data = mergeable_xdp_get_buf(vi, rq, xdp_prog, ctx, &frame_sz, &num_buf, &page,

				     offset, &len, hdr);

	if (unlikely(!data))

		goto err_xdp;



	err = virtnet_build_xdp_buff_mrg(dev, vi, rq, &xdp, data, len, frame_sz,

					 &num_buf, &xdp_frags_truesz, stats);

	if (unlikely(err))

		goto err_xdp;



	act = virtnet_xdp_handler(xdp_prog, &xdp, dev, xdp_xmit, stats);



	switch (act) {

	case XDP_PASS:

		head_skb = build_skb_from_xdp_buff(dev, vi, &xdp, xdp_frags_truesz);

		if (unlikely(!head_skb))

			break;

		return head_skb;



	case XDP_TX:

	case XDP_REDIRECT:

		return NULL;



	default:

		break;

	}



	put_xdp_frags(&xdp);



err_xdp:

	put_page(page);

	mergeable_buf_free(rq, num_buf, dev, stats);



	stats->xdp_drops++;

	stats->drops++;

	return NULL;

}



static struct sk_buff *receive_mergeable(struct net_device *dev,

					 struct virtnet_info *vi,

					 struct receive_queue *rq,
@@ -1327,8 +1387,6 @@ static struct sk_buff *receive_mergeable(struct net_device *dev, 
	unsigned int headroom = mergeable_ctx_to_headroom(ctx);

	unsigned int tailroom = headroom ? sizeof(struct skb_shared_info) : 0;

	unsigned int room = SKB_DATA_ALIGN(headroom + tailroom);

	unsigned int frame_sz;

	int err;



	head_skb = NULL;

	stats->bytes += len - vi->hdr_len;
@@ -1348,41 +1406,10 @@ static struct sk_buff *receive_mergeable(struct net_device *dev, 
	rcu_read_lock();

	xdp_prog = rcu_dereference(rq->xdp_prog);

	if (xdp_prog) {

		unsigned int xdp_frags_truesz = 0;

		struct xdp_buff xdp;

		void *data;

		u32 act;



		data = mergeable_xdp_get_buf(vi, rq, xdp_prog, ctx, &frame_sz,

					     &num_buf, &page, offset, &len, hdr);

		if (unlikely(!data))

			goto err_xdp;



		err = virtnet_build_xdp_buff_mrg(dev, vi, rq, &xdp, data, len, frame_sz,

						 &num_buf, &xdp_frags_truesz, stats);

		if (unlikely(err))

			goto err_xdp;



		act = virtnet_xdp_handler(xdp_prog, &xdp, dev, xdp_xmit, stats);



		switch (act) {

		case XDP_PASS:

			head_skb = build_skb_from_xdp_buff(dev, vi, &xdp, xdp_frags_truesz);

			if (unlikely(!head_skb))

				goto err_xdp_frags;



		head_skb = receive_mergeable_xdp(dev, vi, rq, xdp_prog, buf, ctx,

						 len, xdp_xmit, stats);

		rcu_read_unlock();

		return head_skb;

		case XDP_TX:

		case XDP_REDIRECT:

			rcu_read_unlock();

			goto xdp_xmit;

		default:

			break;

		}

err_xdp_frags:

		put_xdp_frags(&xdp);

		goto err_xdp;

	}

	rcu_read_unlock();
@@ -1452,9 +1479,6 @@ static struct sk_buff *receive_mergeable(struct net_device *dev, 
	ewma_pkt_len_add(&rq->mrg_avg_pkt_len, head_skb->len);

	return head_skb;



err_xdp:

	rcu_read_unlock();

	stats->xdp_drops++;

err_skb:

	put_page(page);

	mergeable_buf_free(rq, num_buf, dev, stats);
@@ -1462,7 +1486,6 @@ static struct sk_buff *receive_mergeable(struct net_device *dev, 
err_buf:

	stats->drops++;

	dev_kfree_skb(head_skb);

xdp_xmit:

	return NULL;

}