C++ (Cpp) vnet_hdr_to_sg Examples

Example #1

File: virtio_net.c Project: Tigrouzen/k1099

static void try_fill_recv(struct virtnet_info *vi)
{
	struct sk_buff *skb;
	struct scatterlist sg[1+MAX_SKB_FRAGS];
	int num, err;

	sg_init_table(sg, 1+MAX_SKB_FRAGS);
	for (;;) {
		skb = netdev_alloc_skb(vi->dev, MAX_PACKET_LEN);
		if (unlikely(!skb))
			break;

		skb_put(skb, MAX_PACKET_LEN);
		vnet_hdr_to_sg(sg, skb);
		num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1;
		skb_queue_head(&vi->recv, skb);

		err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, num, skb);
		if (err) {
			skb_unlink(skb, &vi->recv);
			kfree_skb(skb);
			break;
		}
		vi->num++;
	}
	if (unlikely(vi->num > vi->max))
		vi->max = vi->num;
	vi->rvq->vq_ops->kick(vi->rvq);
}

Example #2

File: virtio_net.c Project: PennPanda/linux-repo

static int start_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct virtnet_info *vi = netdev_priv(dev);
	int num, err;
	struct scatterlist sg[1+MAX_SKB_FRAGS];
	struct virtio_net_hdr *hdr;
	const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
	DECLARE_MAC_BUF(mac);

	sg_init_table(sg, 1+MAX_SKB_FRAGS);

	pr_debug("%s: xmit %p %s\n", dev->name, skb, print_mac(mac, dest));

	free_old_xmit_skbs(vi);

	/* Encode metadata header at front. */
	hdr = skb_vnet_hdr(skb);
	if (skb->ip_summed == CHECKSUM_PARTIAL) {
		hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
		hdr->csum_start = skb->csum_start - skb_headroom(skb);
		hdr->csum_offset = skb->csum_offset;
	} else {
		hdr->flags = 0;
		hdr->csum_offset = hdr->csum_start = 0;
	}

	if (skb_is_gso(skb)) {
		hdr->gso_size = skb_shinfo(skb)->gso_size;
		if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN)
			hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4_ECN;
		else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
			hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
		else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
			hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
		else if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
			hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP;
		else
			BUG();
	} else {
		hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
		hdr->gso_size = 0;
	}

	vnet_hdr_to_sg(sg, skb);
	num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1;
	__skb_queue_head(&vi->send, skb);
	err = vi->svq->vq_ops->add_buf(vi->svq, sg, num, 0, skb);
	if (err) {
		pr_debug("%s: virtio not prepared to send\n", dev->name);
		skb_unlink(skb, &vi->send);
		netif_stop_queue(dev);
		return NETDEV_TX_BUSY;
	}
	vi->svq->vq_ops->kick(vi->svq);

	return 0;
}

Example #3

File: virtio_net.c Project: Tigrouzen/k1099

static int start_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct virtnet_info *vi = netdev_priv(dev);
	int num, err;
	struct scatterlist sg[1+MAX_SKB_FRAGS];
	struct virtio_net_hdr *hdr;
	const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;

	sg_init_table(sg, 1+MAX_SKB_FRAGS);

	pr_debug("%s: xmit %p " MAC_FMT "\n", dev->name, skb,
		 dest[0], dest[1], dest[2],
		 dest[3], dest[4], dest[5]);

	/* Encode metadata header at front. */
	hdr = skb_vnet_hdr(skb);
	if (skb->ip_summed == CHECKSUM_PARTIAL) {
		hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
		hdr->csum_start = skb->csum_start - skb_headroom(skb);
		hdr->csum_offset = skb->csum_offset;
	} else {
		hdr->flags = 0;
		hdr->csum_offset = hdr->csum_start = 0;
	}

	if (skb_is_gso(skb)) {
		hdr->hdr_len = skb_transport_header(skb) - skb->data;
		hdr->gso_size = skb_shinfo(skb)->gso_size;
		if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
			hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
		else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
			hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
		else if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
			hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP;
		else
			BUG();
		if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN)
			hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN;
	} else {
		hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
		hdr->gso_size = hdr->hdr_len = 0;
	}

	vnet_hdr_to_sg(sg, skb);
	num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1;
	__skb_queue_head(&vi->send, skb);

again:
	/* Free up any pending old buffers before queueing new ones. */
	free_old_xmit_skbs(vi);
	err = vi->svq->vq_ops->add_buf(vi->svq, sg, num, 0, skb);
	if (err) {
		pr_debug("%s: virtio not prepared to send\n", dev->name);
		netif_stop_queue(dev);

		/* Activate callback for using skbs: if this returns false it
		 * means some were used in the meantime. */
		if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) {
			vi->svq->vq_ops->disable_cb(vi->svq);
			netif_start_queue(dev);
			goto again;
		}
		__skb_unlink(skb, &vi->send);

		return NETDEV_TX_BUSY;
	}
	vi->svq->vq_ops->kick(vi->svq);

	return 0;
}