udp: Add GRO functions to UDP socket

This patch adds GRO functions (gro_receive and gro_complete) to UDP
sockets. udp_gro_receive is changed to perform socket lookup on a
packet. If a socket is found the related GRO functions are called.

This features obsoletes using UDP offload infrastructure for GRO
(udp_offload). This has the advantage of not being limited to provide
offload on a per port basis, GRO is now applied to whatever individual
UDP sockets are bound to.  This also allows the possbility of
"application defined GRO"-- that is we can attach something like
a BPF program to a UDP socket to perfrom GRO on an application
layer protocol.

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

5 files changed, 21 insertions, 8 deletions

diff --git a/net/ipv6/Makefile b/net/ipv6/Makefile
index 2fbd90b..5e9d6bf 100644
--- a/net/ipv6/Makefile
+++ b/net/ipv6/Makefile
@@ -8,9 +8,10 @@ ipv6-objs :=	af_inet6.o anycast.o ip6_output.o ip6_input.o addrconf.o \
 		addrlabel.o \
 		route.o ip6_fib.o ipv6_sockglue.o ndisc.o udp.o udplite.o \
 		raw.o icmp.o mcast.o reassembly.o tcp_ipv6.o ping.o \
-		exthdrs.o datagram.o ip6_flowlabel.o inet6_connection_sock.o
+		exthdrs.o datagram.o ip6_flowlabel.o inet6_connection_sock.o \
+		udp_offload.o
 
-ipv6-offload :=	ip6_offload.o tcpv6_offload.o udp_offload.o exthdrs_offload.o
+ipv6-offload :=	ip6_offload.o tcpv6_offload.o exthdrs_offload.o
 
 ipv6-$(CONFIG_SYSCTL) = sysctl_net_ipv6.o
 ipv6-$(CONFIG_IPV6_MROUTE) += ip6mr.o
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index 2b78aad..bfa86f0 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -64,6 +64,8 @@
 #include <asm/uaccess.h>
 #include <linux/mroute6.h>
 
+#include "ip6_offload.h"
+
 MODULE_AUTHOR("Cast of dozens");
 MODULE_DESCRIPTION("IPv6 protocol stack for Linux");
 MODULE_LICENSE("GPL");
@@ -959,6 +961,10 @@ static int __init inet6_init(void)
 	if (err)
 		goto udplitev6_fail;
 
+	err = udpv6_offload_init();
+	if (err)
+		goto udpv6_offload_fail;
+
 	err = tcpv6_init();
 	if (err)
 		goto tcpv6_fail;
@@ -988,6 +994,8 @@ pingv6_fail:
 ipv6_packet_fail:
 	tcpv6_exit();
 tcpv6_fail:
+	udpv6_offload_exit();
+udpv6_offload_fail:
 	udplitev6_exit();
 udplitev6_fail:
 	udpv6_exit();
diff --git a/net/ipv6/ip6_offload.c b/net/ipv6/ip6_offload.c
index 82e9f30..204af22 100644
--- a/net/ipv6/ip6_offload.c
+++ b/net/ipv6/ip6_offload.c
@@ -325,8 +325,6 @@ static int __init ipv6_offload_init(void)
 
 	if (tcpv6_offload_init() < 0)
 		pr_crit("%s: Cannot add TCP protocol offload\n", __func__);
-	if (udp_offload_init() < 0)
-		pr_crit("%s: Cannot add UDP protocol offload\n", __func__);
 	if (ipv6_exthdrs_offload_init() < 0)
 		pr_crit("%s: Cannot add EXTHDRS protocol offload\n", __func__);
 
diff --git a/net/ipv6/ip6_offload.h b/net/ipv6/ip6_offload.h
index 2e155c6..96b40e4 100644
--- a/net/ipv6/ip6_offload.h
+++ b/net/ipv6/ip6_offload.h
@@ -12,7 +12,8 @@
 #define __ip6_offload_h
 
 int ipv6_exthdrs_offload_init(void);
-int udp_offload_init(void);
+int udpv6_offload_init(void);
+int udpv6_offload_exit(void);
 int tcpv6_offload_init(void);
 
 #endif
diff --git a/net/ipv6/udp_offload.c b/net/ipv6/udp_offload.c
index 2b0fbe6..5429f6b 100644
--- a/net/ipv6/udp_offload.c
+++ b/net/ipv6/udp_offload.c
@@ -153,7 +153,7 @@ static struct sk_buff **udp6_gro_receive(struct sk_buff **head,
 
 skip:
 	NAPI_GRO_CB(skb)->is_ipv6 = 1;
-	return udp_gro_receive(head, skb, uh);
+	return udp_gro_receive(head, skb, uh, udp6_lib_lookup_skb);
 
 flush:
 	NAPI_GRO_CB(skb)->flush = 1;
@@ -173,7 +173,7 @@ static int udp6_gro_complete(struct sk_buff *skb, int nhoff)
 		skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_TUNNEL;
 	}
 
-	return udp_gro_complete(skb, nhoff);
+	return udp_gro_complete(skb, nhoff, udp6_lib_lookup_skb);
 }
 
 static const struct net_offload udpv6_offload = {
@@ -184,7 +184,12 @@ static const struct net_offload udpv6_offload = {
 	},
 };
 
-int __init udp_offload_init(void)
+int udpv6_offload_init(void)
 {
 	return inet6_add_offload(&udpv6_offload, IPPROTO_UDP);
 }
+
+int udpv6_offload_exit(void)
+{
+	return inet6_del_offload(&udpv6_offload, IPPROTO_UDP);
+}