net: gro: use cb instead of skb->network_header

This patch converts references of skb->network_header to napi_gro_cb's
network_offset and inner_network_offset.

Signed-off-by: Richard Gobert <[e-mail]>
Reviewed-by: Willem de Bruijn <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Jakub Kicinski <[e-mail]>

include/net/gro.h

···
 	return ptr;
 }
 
+static inline int skb_gro_receive_network_offset(const struct sk_buff *skb)
+{
+	return NAPI_GRO_CB(skb)->network_offsets[NAPI_GRO_CB(skb)->encap_mark];
+}
+
 static inline void *skb_gro_network_header(const struct sk_buff *skb)
 {
 	if (skb_gro_may_pull(skb, skb_gro_offset(skb)))
-		return skb_gro_header_fast(skb, skb_network_offset(skb));
+		return skb_gro_header_fast(skb, skb_gro_receive_network_offset(skb));
 
-	return skb_network_header(skb);
+	return skb->data + skb_gro_receive_network_offset(skb);
 }
 
 static inline __wsum inet_gro_compute_pseudo(const struct sk_buff *skb,

net/ipv4/af_inet.c

···
 
 	NAPI_GRO_CB(skb)->is_atomic = !!(iph->frag_off & htons(IP_DF));
 	NAPI_GRO_CB(skb)->flush |= flush;
-	skb_set_network_header(skb, off);
-	/* The above will be needed by the transport layer if there is one
-	 * immediately following this IP hdr.
-	 */
 	NAPI_GRO_CB(skb)->inner_network_offset = off;
 
 	/* Note : No need to call skb_gro_postpull_rcsum() here,

net/ipv4/tcp_offload.c

···
 
 INDIRECT_CALLABLE_SCOPE int tcp4_gro_complete(struct sk_buff *skb, int thoff)
 {
-	const struct iphdr *iph = ip_hdr(skb);
+	const u16 offset = NAPI_GRO_CB(skb)->network_offsets[skb->encapsulation];
+	const struct iphdr *iph = (struct iphdr *)(skb->data + offset);
 	struct tcphdr *th = tcp_hdr(skb);
 
 	if (unlikely(NAPI_GRO_CB(skb)->is_flist)) {

net/ipv6/ip6_offload.c

···
 		off += len;
 	}
 
-	skb_gro_pull(skb, off - skb_network_offset(skb));
+	skb_gro_pull(skb, off - skb_gro_receive_network_offset(skb));
 	return proto;
 }
 
···
 	if (unlikely(!iph))
 		goto out;
 
-	skb_set_network_header(skb, off);
 	NAPI_GRO_CB(skb)->inner_network_offset = off;
 
 	flush += ntohs(iph->payload_len) != skb->len - hlen;
···
 	NAPI_GRO_CB(skb)->proto = proto;
 
 	flush--;
-	nlen = skb_network_header_len(skb);
+	nlen = skb_gro_offset(skb) - off;
 
 	list_for_each_entry(p, head, list) {
 		const struct ipv6hdr *iph2;

net/ipv6/tcpv6_offload.c

···
 
 INDIRECT_CALLABLE_SCOPE int tcp6_gro_complete(struct sk_buff *skb, int thoff)
 {
-	const struct ipv6hdr *iph = ipv6_hdr(skb);
+	const u16 offset = NAPI_GRO_CB(skb)->network_offsets[skb->encapsulation];
+	const struct ipv6hdr *iph = (struct ipv6hdr *)(skb->data + offset);
 	struct tcphdr *th = tcp_hdr(skb);
 
 	if (unlikely(NAPI_GRO_CB(skb)->is_flist)) {