Commit 81fbc812 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

ipv6/gro: insert temporary HBH/jumbo header 



Following patch will add GRO_IPV6_MAX_SIZE, allowing gro to build
BIG TCP ipv6 packets (bigger than 64K).

This patch changes ipv6_gro_complete() to insert a HBH/jumbo header
so that resulting packet can go through IPv6/TCP stacks.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Acked-by: default avatarAlexander Duyck <alexanderduyck@fb.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 09f3d1a3

net/ipv6/ip6_offload.c

+30 −2
Original line number Diff line number Diff line
@@ -342,15 +342,43 @@ static struct sk_buff *ip4ip6_gro_receive(struct list_head *head, 
INDIRECT_CALLABLE_SCOPE int ipv6_gro_complete(struct sk_buff *skb, int nhoff)

{

	const struct net_offload *ops;

	struct ipv6hdr *iph = (struct ipv6hdr *)(skb->data + nhoff);

	struct ipv6hdr *iph;

	int err = -ENOSYS;

	u32 payload_len;



	if (skb->encapsulation) {

		skb_set_inner_protocol(skb, cpu_to_be16(ETH_P_IPV6));

		skb_set_inner_network_header(skb, nhoff);

	}



	iph->payload_len = htons(skb->len - nhoff - sizeof(*iph));

	payload_len = skb->len - nhoff - sizeof(*iph);

	if (unlikely(payload_len > IPV6_MAXPLEN)) {

		struct hop_jumbo_hdr *hop_jumbo;

		int hoplen = sizeof(*hop_jumbo);



		/* Move network header left */

		memmove(skb_mac_header(skb) - hoplen, skb_mac_header(skb),

			skb->transport_header - skb->mac_header);

		skb->data -= hoplen;

		skb->len += hoplen;

		skb->mac_header -= hoplen;

		skb->network_header -= hoplen;

		iph = (struct ipv6hdr *)(skb->data + nhoff);

		hop_jumbo = (struct hop_jumbo_hdr *)(iph + 1);



		/* Build hop-by-hop options */

		hop_jumbo->nexthdr = iph->nexthdr;

		hop_jumbo->hdrlen = 0;

		hop_jumbo->tlv_type = IPV6_TLV_JUMBO;

		hop_jumbo->tlv_len = 4;

		hop_jumbo->jumbo_payload_len = htonl(payload_len + hoplen);



		iph->nexthdr = NEXTHDR_HOP;

		iph->payload_len = 0;

	} else {

		iph = (struct ipv6hdr *)(skb->data + nhoff);

		iph->payload_len = htons(payload_len);

	}



	nhoff += sizeof(*iph) + ipv6_exthdrs_len(iph, &ops);

	if (WARN_ON(!ops || !ops->callbacks.gro_complete))