[1/2] ipv6: Add GRO support

[1/2] ipv6: Add GRO support

[Herbert Xu]

Hi Dave:

Give an inch and take a mile, parity with LRO just isn't enough :)
I've tested it locally and it does work.

ipv6: Add GRO support

This patch adds GRO support for IPv6.  IPv6 GRO supports extension
headers in the same way as GSO (by using the same infrastructure).
It's also simpler compared to IPv4 since we no longer have to worry
about fragmentation attributes or header checksums.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/include/net/protocol.h b/include/net/protocol.h
index cb2965a..ffa5b8b 100644
--- a/include/net/protocol.h
+++ b/include/net/protocol.h
@@ -59,6 +59,9 @@ struct inet6_protocol
 	int	(*gso_send_check)(struct sk_buff *skb);
 	struct sk_buff *(*gso_segment)(struct sk_buff *skb,
 				       int features);
+	struct sk_buff **(*gro_receive)(struct sk_buff **head,
+					struct sk_buff *skb);
+	int	(*gro_complete)(struct sk_buff *skb);
 
 	unsigned int	flags;	/* INET6_PROTO_xxx */
 };
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index 437b750..94f74f5 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -672,8 +672,7 @@ int ipv6_opt_accepted(struct sock *sk, struct sk_buff *skb)
 
 EXPORT_SYMBOL_GPL(ipv6_opt_accepted);
 
-static struct inet6_protocol *ipv6_gso_pull_exthdrs(struct sk_buff *skb,
-						    int proto)
+static int ipv6_gso_pull_exthdrs(struct sk_buff *skb, int proto)
 {
 	struct inet6_protocol *ops = NULL;
 
@@ -704,7 +703,7 @@ static struct inet6_protocol *ipv6_gso_pull_exthdrs(struct sk_buff *skb,
 		__skb_pull(skb, len);
 	}
 
-	return ops;
+	return proto;
 }
 
 static int ipv6_gso_send_check(struct sk_buff *skb)
@@ -721,7 +720,9 @@ static int ipv6_gso_send_check(struct sk_buff *skb)
 	err = -EPROTONOSUPPORT;
 
 	rcu_read_lock();
-	ops = ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr);
+	ops = rcu_dereference(inet6_protos[
+		ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr)]);
+
 	if (likely(ops && ops->gso_send_check)) {
 		skb_reset_transport_header(skb);
 		err = ops->gso_send_check(skb);
@@ -757,7 +758,9 @@ static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb, int features)
 	segs = ERR_PTR(-EPROTONOSUPPORT);
 
 	rcu_read_lock();
-	ops = ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr);
+	ops = rcu_dereference(inet6_protos[
+		ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr)]);
+
 	if (likely(ops && ops->gso_segment)) {
 		skb_reset_transport_header(skb);
 		segs = ops->gso_segment(skb, features);
@@ -777,11 +780,105 @@ out:
 	return segs;
 }
 
+struct ipv6_gro_cb {
+	struct napi_gro_cb napi;
+	int proto;
+};
+
+#define IPV6_GRO_CB(skb) ((struct ipv6_gro_cb *)(skb)->cb)
+
+static struct sk_buff **ipv6_gro_receive(struct sk_buff **head,
+					 struct sk_buff *skb)
+{
+	struct inet6_protocol *ops;
+	struct sk_buff **pp = NULL;
+	struct sk_buff *p;
+	struct ipv6hdr *iph;
+	unsigned int nlen;
+	int flush = 1;
+	int proto;
+
+	if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
+		goto out;
+
+	iph = ipv6_hdr(skb);
+	__skb_pull(skb, sizeof(*iph));
+
+	flush += ntohs(iph->payload_len) != skb->len;
+
+	rcu_read_lock();
+	proto = ipv6_gso_pull_exthdrs(skb, iph->nexthdr);
+	IPV6_GRO_CB(skb)->proto = proto;
+	ops = rcu_dereference(inet6_protos[proto]);
+	if (!ops || !ops->gro_receive)
+		goto out_unlock;
+
+	flush--;
+	skb_reset_transport_header(skb);
+	nlen = skb_network_header_len(skb);
+
+	for (p = *head; p; p = p->next) {
+		struct ipv6hdr *iph2;
+
+		if (!NAPI_GRO_CB(p)->same_flow)
+			continue;
+
+		iph2 = ipv6_hdr(p);
+
+		/* All fields must match except length. */
+		if (nlen != skb_network_header_len(p) ||
+		    memcmp(iph, iph2, offsetof(struct ipv6hdr, payload_len)) ||
+		    memcmp(&iph->nexthdr, &iph2->nexthdr,
+			   nlen - offsetof(struct ipv6hdr, nexthdr))) {
+			NAPI_GRO_CB(p)->same_flow = 0;
+			continue;
+		}
+
+		NAPI_GRO_CB(p)->flush |= flush;
+	}
+
+	NAPI_GRO_CB(skb)->flush |= flush;
+
+	pp = ops->gro_receive(head, skb);
+
+out_unlock:
+	rcu_read_unlock();
+
+out:
+	NAPI_GRO_CB(skb)->flush |= flush;
+
+	return pp;
+}
+
+static int ipv6_gro_complete(struct sk_buff *skb)
+{
+	struct inet6_protocol *ops;
+	struct ipv6hdr *iph = ipv6_hdr(skb);
+	int err = -ENOSYS;
+
+	iph->payload_len = htons(skb->len - skb_network_offset(skb) -
+				 sizeof(*iph));
+
+	rcu_read_lock();
+	ops = rcu_dereference(inet6_protos[IPV6_GRO_CB(skb)->proto]);
+	if (WARN_ON(!ops || !ops->gro_complete))
+		goto out_unlock;
+
+	err = ops->gro_complete(skb);
+
+out_unlock:
+	rcu_read_unlock();
+
+	return err;
+}
+
 static struct packet_type ipv6_packet_type = {
 	.type = __constant_htons(ETH_P_IPV6),
 	.func = ipv6_rcv,
 	.gso_send_check = ipv6_gso_send_check,
 	.gso_segment = ipv6_gso_segment,
+	.gro_receive = ipv6_gro_receive,
+	.gro_complete = ipv6_gro_complete,
 };
 
 static int __init ipv6_packet_init(void)

Cheers,
-- 
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

[2/2] tcp6: Add GRO support

[Herbert Xu]

tcp6: Add GRO support

This patch adds GRO support for TCP over IPv6.  The code is exactly
the same as the IPv4 version except for the pseudo-header checksum
computation.

Note that I've removed the unused tcphdr argument from tcp_v6_check
rather than invent a bogus value for GRO.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 218a6e5..e23bbb6 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -2545,6 +2545,7 @@ out:
 
 	return pp;
 }
+EXPORT_SYMBOL(tcp_gro_receive);
 
 int tcp_gro_complete(struct sk_buff *skb)
 {
@@ -2561,6 +2562,7 @@ int tcp_gro_complete(struct sk_buff *skb)
 
 	return 0;
 }
+EXPORT_SYMBOL(tcp_gro_complete);
 
 #ifdef CONFIG_TCP_MD5SIG
 static unsigned long tcp_md5sig_users;
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 8702b06..be668ac 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -100,7 +100,7 @@ static void tcp_v6_hash(struct sock *sk)
 	}
 }
 
-static __inline__ __sum16 tcp_v6_check(struct tcphdr *th, int len,
+static __inline__ __sum16 tcp_v6_check(int len,
 				   struct in6_addr *saddr,
 				   struct in6_addr *daddr,
 				   __wsum base)
@@ -500,7 +500,7 @@ static int tcp_v6_send_synack(struct sock *sk, struct request_sock *req)
 	if (skb) {
 		struct tcphdr *th = tcp_hdr(skb);
 
-		th->check = tcp_v6_check(th, skb->len,
+		th->check = tcp_v6_check(skb->len,
 					 &treq->loc_addr, &treq->rmt_addr,
 					 csum_partial(th, skb->len, skb->csum));
 
@@ -941,6 +941,41 @@ static int tcp_v6_gso_send_check(struct sk_buff *skb)
 	return 0;
 }
 
+struct sk_buff **tcp6_gro_receive(struct sk_buff **head, struct sk_buff *skb)
+{
+	struct ipv6hdr *iph = ipv6_hdr(skb);
+
+	switch (skb->ip_summed) {
+	case CHECKSUM_COMPLETE:
+		if (!tcp_v6_check(skb->len, &iph->saddr, &iph->daddr,
+				  skb->csum)) {
+			skb->ip_summed = CHECKSUM_UNNECESSARY;
+			break;
+		}
+
+		/* fall through */
+	case CHECKSUM_NONE:
+		NAPI_GRO_CB(skb)->flush = 1;
+		return NULL;
+	}
+
+	return tcp_gro_receive(head, skb);
+}
+EXPORT_SYMBOL(tcp6_gro_receive);
+
+int tcp6_gro_complete(struct sk_buff *skb)
+{
+	struct ipv6hdr *iph = ipv6_hdr(skb);
+	struct tcphdr *th = tcp_hdr(skb);
+
+	th->check = ~tcp_v6_check(skb->len - skb_transport_offset(skb),
+				  &iph->saddr, &iph->daddr, 0);
+	skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
+
+	return tcp_gro_complete(skb);
+}
+EXPORT_SYMBOL(tcp6_gro_complete);
+
 static void tcp_v6_send_response(struct sk_buff *skb, u32 seq, u32 ack, u32 win,
 				 u32 ts, struct tcp_md5sig_key *key, int rst)
 {
@@ -1428,14 +1463,14 @@ out:
 static __sum16 tcp_v6_checksum_init(struct sk_buff *skb)
 {
 	if (skb->ip_summed == CHECKSUM_COMPLETE) {
-		if (!tcp_v6_check(tcp_hdr(skb), skb->len, &ipv6_hdr(skb)->saddr,
+		if (!tcp_v6_check(skb->len, &ipv6_hdr(skb)->saddr,
 				  &ipv6_hdr(skb)->daddr, skb->csum)) {
 			skb->ip_summed = CHECKSUM_UNNECESSARY;
 			return 0;
 		}
 	}
 
-	skb->csum = ~csum_unfold(tcp_v6_check(tcp_hdr(skb), skb->len,
+	skb->csum = ~csum_unfold(tcp_v6_check(skb->len,
 					      &ipv6_hdr(skb)->saddr,
 					      &ipv6_hdr(skb)->daddr, 0));
 
@@ -2059,6 +2094,8 @@ static struct inet6_protocol tcpv6_protocol = {
 	.err_handler	=	tcp_v6_err,
 	.gso_send_check	=	tcp_v6_gso_send_check,
 	.gso_segment	=	tcp_tso_segment,
+	.gro_receive	=	tcp6_gro_receive,
+	.gro_complete	=	tcp6_gro_complete,
 	.flags		=	INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
 };

Cheers,
-- 
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

Re: [2/2] tcp6: Add GRO support

[David Miller]

From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Wed, 7 Jan 2009 14:15:36 +1100

> tcp6: Add GRO support
> 
> This patch adds GRO support for TCP over IPv6.  The code is exactly
> the same as the IPv4 version except for the pseudo-header checksum
> computation.
> 
> Note that I've removed the unused tcphdr argument from tcp_v6_check
> rather than invent a bogus value for GRO.
> 
> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Applied.

Re: [1/2] ipv6: Add GRO support

[David Miller]

From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Wed, 7 Jan 2009 14:14:04 +1100

> ipv6: Add GRO support
> 
> This patch adds GRO support for IPv6.  IPv6 GRO supports extension
> headers in the same way as GSO (by using the same infrastructure).
> It's also simpler compared to IPv4 since we no longer have to worry
> about fragmentation attributes or header checksums.
> 
> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Applied.