commit 57c67ff4bd92af634f7c91c40eb02a96dd785dda
author Tom Herbert <therbert@google.com> Fri Aug 22 13:34:44 2014 -0700
committer David S. Miller <davem@davemloft.net> Sun Aug 24 18:09:24 2014 -0700
tree f10aac8b764b6254075ebcba255285140d1cabea
parent 149d0774a729497c6a876260d3884826088724b6

udp: additional GRO support

Implement GRO for UDPv6. Add UDP checksum verification in gro_receive
for both UDP4 and UDP6 calling skb_gro_checksum_validate_zero_check.

Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv6/udp_offload.c

diff --git a/net/ipv6/udp_offload.c b/net/ipv6/udp_offload.c
index 0ae3d98..b13e377 100644
--- a/net/ipv6/udp_offload.c
+++ b/net/ipv6/udp_offload.c
@@ -10,6 +10,7 @@
  *      UDPv6 GSO support
  */
 #include <linux/skbuff.h>
+#include <linux/netdevice.h>
 #include <net/protocol.h>
 #include <net/ipv6.h>
 #include <net/udp.h>
@@ -127,10 +128,42 @@
 out:
 	return segs;
 }
+
+static struct sk_buff **udp6_gro_receive(struct sk_buff **head,
+					 struct sk_buff *skb)
+{
+	struct udphdr *uh = udp_gro_udphdr(skb);
+
+	/* Don't bother verifying checksum if we're going to flush anyway. */
+	if (unlikely(!uh) ||
+	    (!NAPI_GRO_CB(skb)->flush &&
+	     skb_gro_checksum_validate_zero_check(skb, IPPROTO_UDP, uh->check,
+						  ip6_gro_compute_pseudo))) {
+		NAPI_GRO_CB(skb)->flush = 1;
+		return NULL;
+	}
+
+	return udp_gro_receive(head, skb, uh);
+}
+
+int udp6_gro_complete(struct sk_buff *skb, int nhoff)
+{
+	const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
+	struct udphdr *uh = (struct udphdr *)(skb->data + nhoff);
+
+	if (uh->check)
+		uh->check = ~udp_v6_check(skb->len - nhoff, &ipv6h->saddr,
+					  &ipv6h->daddr, 0);
+
+	return udp_gro_complete(skb, nhoff);
+}
+
 static const struct net_offload udpv6_offload = {
 	.callbacks = {
 		.gso_send_check =	udp6_ufo_send_check,
 		.gso_segment	=	udp6_ufo_fragment,
+		.gro_receive	=	udp6_gro_receive,
+		.gro_complete	=	udp6_gro_complete,
 	},
 };