ip4ip6: Support for GSO/GRO

Signed-off-by: Tom Herbert <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

include/net/inet_common.h

···
 int inet_recv_error(struct sock *sk, struct msghdr *msg, int len,
 		    int *addr_len);
 
+struct sk_buff **inet_gro_receive(struct sk_buff **head, struct sk_buff *skb);
+int inet_gro_complete(struct sk_buff *skb, int nhoff);
+struct sk_buff *inet_gso_segment(struct sk_buff *skb,
+				 netdev_features_t features);
+
 static inline void inet_ctl_sock_destroy(struct sock *sk)
 {
 	if (sk)

net/ipv4/af_inet.c

···
 }
 EXPORT_SYMBOL(inet_sk_rebuild_header);
 
-static struct sk_buff *inet_gso_segment(struct sk_buff *skb,
-					netdev_features_t features)
+struct sk_buff *inet_gso_segment(struct sk_buff *skb,
+				 netdev_features_t features)
 {
 	bool udpfrag = false, fixedid = false, encap;
 	struct sk_buff *segs = ERR_PTR(-EINVAL);
···
 out:
 	return segs;
 }
+EXPORT_SYMBOL(inet_gso_segment);
 
-static struct sk_buff **inet_gro_receive(struct sk_buff **head,
-					 struct sk_buff *skb)
+struct sk_buff **inet_gro_receive(struct sk_buff **head, struct sk_buff *skb)
 {
 	const struct net_offload *ops;
 	struct sk_buff **pp = NULL;
···
 
 	return pp;
 }
+EXPORT_SYMBOL(inet_gro_receive);
 
 static struct sk_buff **ipip_gro_receive(struct sk_buff **head,
 					 struct sk_buff *skb)
···
 	return -EINVAL;
 }
 
-static int inet_gro_complete(struct sk_buff *skb, int nhoff)
+int inet_gro_complete(struct sk_buff *skb, int nhoff)
 {
 	__be16 newlen = htons(skb->len - nhoff);
 	struct iphdr *iph = (struct iphdr *)(skb->data + nhoff);
···
 
 	return err;
 }
+EXPORT_SYMBOL(inet_gro_complete);
 
 static int ipip_gro_complete(struct sk_buff *skb, int nhoff)
 {

net/ipv6/ip6_offload.c

···
 
 #include <net/protocol.h>
 #include <net/ipv6.h>
+#include <net/inet_common.h>
 
 #include "ip6_offload.h"
 
···
 	return ipv6_gro_receive(head, skb);
 }
 
+static struct sk_buff **ip4ip6_gro_receive(struct sk_buff **head,
+					   struct sk_buff *skb)
+{
+	/* Common GRO receive for SIT and IP6IP6 */
+
+	if (NAPI_GRO_CB(skb)->encap_mark) {
+		NAPI_GRO_CB(skb)->flush = 1;
+		return NULL;
+	}
+
+	NAPI_GRO_CB(skb)->encap_mark = 1;
+
+	return inet_gro_receive(head, skb);
+}
+
 static int ipv6_gro_complete(struct sk_buff *skb, int nhoff)
 {
 	const struct net_offload *ops;
···
 	return ipv6_gro_complete(skb, nhoff);
 }
 
+static int ip4ip6_gro_complete(struct sk_buff *skb, int nhoff)
+{
+	skb->encapsulation = 1;
+	skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP6;
+	return inet_gro_complete(skb, nhoff);
+}
+
 static struct packet_offload ipv6_packet_offload __read_mostly = {
 	.type = cpu_to_be16(ETH_P_IPV6),
 	.callbacks = {
···
 	},
 };
 
+static const struct net_offload ip4ip6_offload = {
+	.callbacks = {
+		.gso_segment	= inet_gso_segment,
+		.gro_receive    = ip4ip6_gro_receive,
+		.gro_complete   = ip4ip6_gro_complete,
+	},
+};
+
 static const struct net_offload ip6ip6_offload = {
 	.callbacks = {
 		.gso_segment	= ipv6_gso_segment,
···
 		.gro_complete   = ip6ip6_gro_complete,
 	},
 };
-
 static int __init ipv6_offload_init(void)
 {
 
···
 
 	inet_add_offload(&sit_offload, IPPROTO_IPV6);
 	inet6_add_offload(&ip6ip6_offload, IPPROTO_IPV6);
+	inet6_add_offload(&ip4ip6_offload, IPPROTO_IPIP);
 
 	return 0;
 }

net/ipv6/ip6_tunnel.c

···
 	if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
 		fl6.flowi6_mark = skb->mark;
 
+	if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP6))
+		return -1;
+
+	skb_set_inner_ipproto(skb, IPPROTO_IPIP);
+
 	err = ip6_tnl_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu,
 			   IPPROTO_IPIP);
 	if (err != 0) {