ipv4: generalize gre_handle_offloads

This patch makes gre_handle_offloads() more generic
and rename it to iptunnel_handle_offloads()

This will be used to add GSO/TSO support to IPIP tunnels.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/gre.h

@@ -38,7 +38,13 @@ void gre_offload_exit(void);
 
 void gre_build_header(struct sk_buff *skb, const struct tnl_ptk_info *tpi,
 		      int hdr_len);
-struct sk_buff *gre_handle_offloads(struct sk_buff *skb, bool gre_csum);
+
+static inline struct sk_buff *gre_handle_offloads(struct sk_buff *skb,
+						  bool gre_csum)
+{
+	return iptunnel_handle_offloads(skb, gre_csum, SKB_GSO_GRE);
+}
+
 
 static inline int ip_gre_calc_hlen(__be16 o_flags)
 {

include/net/ip_tunnels.h

@@ -150,6 +150,9 @@ int iptunnel_xmit(struct rtable *rt, struct sk_buff *skb,
 		  __be32 src, __be32 dst, __u8 proto,
 		  __u8 tos, __u8 ttl, __be16 df, bool xnet);
 
+struct sk_buff *iptunnel_handle_offloads(struct sk_buff *skb, bool gre_csum,
+					 int gso_type_mask);
+
 static inline void iptunnel_xmit_stats(int err,
 				       struct net_device_stats *err_stats,
 				       struct pcpu_tstats __percpu *stats)

net/ipv4/gre_demux.c

@@ -93,35 +93,6 @@ void gre_build_header(struct sk_buff *skb, const struct tnl_ptk_info *tpi,
 }
 EXPORT_SYMBOL_GPL(gre_build_header);
 
-struct sk_buff *gre_handle_offloads(struct sk_buff *skb, bool gre_csum)
-{
-	int err;
-
-	if (likely(!skb->encapsulation)) {
-		skb_reset_inner_headers(skb);
-		skb->encapsulation = 1;
-	}
-
-	if (skb_is_gso(skb)) {
-		err = skb_unclone(skb, GFP_ATOMIC);
-		if (unlikely(err))
-			goto error;
-		skb_shinfo(skb)->gso_type |= SKB_GSO_GRE;
-		return skb;
-	} else if (skb->ip_summed == CHECKSUM_PARTIAL && gre_csum) {
-		err = skb_checksum_help(skb);
-		if (unlikely(err))
-			goto error;
-	} else if (skb->ip_summed != CHECKSUM_PARTIAL)
-		skb->ip_summed = CHECKSUM_NONE;
-
-	return skb;
-error:
-	kfree_skb(skb);
-	return ERR_PTR(err);
-}
-EXPORT_SYMBOL_GPL(gre_handle_offloads);
-
 static __sum16 check_checksum(struct sk_buff *skb)
 {
 	__sum16 csum = 0;

net/ipv4/ip_tunnel_core.c

@@ -116,3 +116,36 @@ int iptunnel_pull_header(struct sk_buff *skb, int hdr_len, __be16 inner_proto)
 	return 0;
 }
 EXPORT_SYMBOL_GPL(iptunnel_pull_header);
+
+struct sk_buff *iptunnel_handle_offloads(struct sk_buff *skb,
+					 bool csum_help,
+					 int gso_type_mask)
+{
+	int err;
+
+	if (likely(!skb->encapsulation)) {
+		skb_reset_inner_headers(skb);
+		skb->encapsulation = 1;
+	}
+
+	if (skb_is_gso(skb)) {
+		err = skb_unclone(skb, GFP_ATOMIC);
+		if (unlikely(err))
+			goto error;
+		skb_shinfo(skb)->gso_type |= gso_type_mask;
+		return skb;
+	}
+
+	if (skb->ip_summed == CHECKSUM_PARTIAL && csum_help) {
+		err = skb_checksum_help(skb);
+		if (unlikely(err))
+			goto error;
+	} else if (skb->ip_summed != CHECKSUM_PARTIAL)
+		skb->ip_summed = CHECKSUM_NONE;
+
+	return skb;
+error:
+	kfree_skb(skb);
+	return ERR_PTR(err);
+}
+EXPORT_SYMBOL_GPL(iptunnel_handle_offloads);