[SK_BUFF]: Introduce skb_network_header_len

For the common sequence "skb->h.raw - skb->nh.raw", similar to skb->mac_len,
that is precalculated tho, don't think we need to bloat skb with one more
member, so just use this new helper, reducing the number of non-skbuff.h
references to the layer headers even more.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

14 files changed, 27 insertions, 21 deletions

diff --git a/drivers/net/gianfar.c b/drivers/net/gianfar.c
index b9f44602c5e1..b666a0cc0642 100644
--- a/drivers/net/gianfar.c
+++ b/drivers/net/gianfar.c
@@ -953,7 +953,7 @@ static inline void gfar_tx_checksum(struct sk_buff *skb, struct txfcb *fcb)
          * l4os is the distance between the start of the
          * l3 hdr and the l4 hdr */
         fcb->l3os = (u16)(skb_network_offset(skb) - GMAC_FCB_LEN);
-        fcb->l4os = (u16)(skb->h.raw - skb->nh.raw);
+        fcb->l4os = skb_network_header_len(skb);
 
         fcb->flags = flags;
 }
diff --git a/drivers/net/pasemi_mac.c b/drivers/net/pasemi_mac.c
index 1d8129986cc5..76fe9dd8e841 100644
--- a/drivers/net/pasemi_mac.c
+++ b/drivers/net/pasemi_mac.c
@@ -734,12 +734,12 @@ static int pasemi_mac_start_tx(struct sk_buff *skb, struct net_device *dev)
                 switch (ip_hdr(skb)->protocol) {
                 case IPPROTO_TCP:
                         dflags |= XCT_MACTX_CSUM_TCP;
-                        dflags |= XCT_MACTX_IPH((skb->h.raw - skb->nh.raw) >> 2);
+                        dflags |= XCT_MACTX_IPH(skb_network_header_len(skb) >> 2);
                         dflags |= XCT_MACTX_IPO(nh - skb->data);
                         break;
                 case IPPROTO_UDP:
                         dflags |= XCT_MACTX_CSUM_UDP;
-                        dflags |= XCT_MACTX_IPH((skb->h.raw - skb->nh.raw) >> 2);
+                        dflags |= XCT_MACTX_IPH(skb_network_header_len(skb) >> 2);
                         dflags |= XCT_MACTX_IPO(nh - skb->data);
                         break;
                 }
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 47c57be97d43..230dd43fc9b3 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -992,6 +992,11 @@ static inline int skb_network_offset(const struct sk_buff *skb)
         return skb->nh.raw - skb->data;
 }
 
+static inline u32 skb_network_header_len(const struct sk_buff *skb)
+{
+        return skb->h.raw - skb->nh.raw;
+}
+
 static inline unsigned char *skb_mac_header(const struct sk_buff *skb)
 {
         return skb->mac.raw;
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 87e000633f41..f38af6c01b12 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -1906,7 +1906,7 @@ struct sk_buff *skb_segment(struct sk_buff *skb, int features)
                 skb_reserve(nskb, headroom);
                 skb_reset_mac_header(nskb);
                 skb_set_network_header(nskb, skb->mac_len);
-                nskb->h.raw = nskb->nh.raw + (skb->h.raw - skb->nh.raw);
+                nskb->h.raw = nskb->nh.raw + skb_network_header_len(skb);
                 memcpy(skb_put(nskb, doffset), skb->data, doffset);
 
                 if (!sg) {
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 11a6ac756f8c..02988fb262d6 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -1187,7 +1187,7 @@ int ip_push_pending_frames(struct sock *sk)
         if (skb->data < skb_network_header(skb))
                 __skb_pull(skb, skb_network_offset(skb));
         while ((tmp_skb = __skb_dequeue(&sk->sk_write_queue)) != NULL) {
-                __skb_pull(tmp_skb, skb->h.raw - skb->nh.raw);
+                __skb_pull(tmp_skb, skb_network_header_len(skb));
                 *tail_skb = tmp_skb;
                 tail_skb = &(tmp_skb->next);
                 skb->len += tmp_skb->len;
diff --git a/net/ipv6/esp6.c b/net/ipv6/esp6.c
index 436eb9e6a6cf..7fdf84dee73f 100644
--- a/net/ipv6/esp6.c
+++ b/net/ipv6/esp6.c
@@ -147,8 +147,7 @@ static int esp6_input(struct xfrm_state *x, struct sk_buff *skb)
         int blksize = ALIGN(crypto_blkcipher_blocksize(tfm), 4);
         int alen = esp->auth.icv_trunc_len;
         int elen = skb->len - sizeof(struct ipv6_esp_hdr) - esp->conf.ivlen - alen;
-
-        int hdr_len = skb->h.raw - skb->nh.raw;
+        int hdr_len = skb_network_header_len(skb);
         int nfrags;
         int ret = 0;
 
diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c
index f763409ea740..f34cc2bd489a 100644
--- a/net/ipv6/exthdrs.c
+++ b/net/ipv6/exthdrs.c
@@ -143,7 +143,7 @@ static int ip6_parse_tlv(struct tlvtype_proc *procs, struct sk_buff **skbp)
         struct sk_buff *skb = *skbp;
         struct tlvtype_proc *curr;
         const unsigned char *nh = skb_network_header(skb);
-        int off = skb->h.raw - skb->nh.raw;
+        int off = skb_network_header_len(skb);
         int len = (skb_transport_header(skb)[1] + 1) << 3;
 
         if (skb_transport_offset(skb) + len > skb_headlen(skb))
@@ -297,7 +297,7 @@ static int ipv6_destopt_rcv(struct sk_buff **skbp)
                 return -1;
         }
 
-        opt->lastopt = opt->dst1 = skb->h.raw - skb->nh.raw;
+        opt->lastopt = opt->dst1 = skb_network_header_len(skb);
 #ifdef CONFIG_IPV6_MIP6
         dstbuf = opt->dst1;
 #endif
@@ -443,7 +443,7 @@ looped_back:
                         break;
                 }
 
-                opt->lastopt = opt->srcrt = skb->h.raw - skb->nh.raw;
+                opt->lastopt = opt->srcrt = skb_network_header_len(skb);
                 skb->h.raw += (hdr->hdrlen + 1) << 3;
                 opt->dst0 = opt->dst1;
                 opt->dst1 = 0;
@@ -738,7 +738,7 @@ int ipv6_parse_hopopts(struct sk_buff **skbp)
 
         /*
          * skb_network_header(skb) is equal to skb->data, and
-         * skb->h.raw - skb->nh.raw is always equal to
+         * skb_network_header_len(skb) is always equal to
          * sizeof(struct ipv6hdr) by definition of
          * hop-by-hop options.
          */
diff --git a/net/ipv6/ip6_input.c b/net/ipv6/ip6_input.c
index 44275411d1a8..cf0c4406b59e 100644
--- a/net/ipv6/ip6_input.c
+++ b/net/ipv6/ip6_input.c
@@ -182,7 +182,7 @@ resubmit:
                         nf_reset(skb);
 
                         skb_postpull_rcsum(skb, skb_network_header(skb),
-                                           skb->h.raw - skb->nh.raw);
+                                           skb_network_header_len(skb));
                         hdr = ipv6_hdr(skb);
                         if (ipv6_addr_is_multicast(&hdr->daddr) &&
                             !ipv6_chk_mcast_addr(skb->dev, &hdr->daddr,
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 32e8c3f73c79..57a326080757 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -1325,7 +1325,7 @@ int ip6_push_pending_frames(struct sock *sk)
         if (skb->data < skb_network_header(skb))
                 __skb_pull(skb, skb_network_offset(skb));
         while ((tmp_skb = __skb_dequeue(&sk->sk_write_queue)) != NULL) {
-                __skb_pull(tmp_skb, skb->h.raw - skb->nh.raw);
+                __skb_pull(tmp_skb, skb_network_header_len(skb));
                 *tail_skb = tmp_skb;
                 tail_skb = &(tmp_skb->next);
                 skb->len += tmp_skb->len;
@@ -1337,7 +1337,7 @@ int ip6_push_pending_frames(struct sock *sk)
         }
 
         ipv6_addr_copy(final_dst, &fl->fl6_dst);
-        __skb_pull(skb, skb->h.raw - skb->nh.raw);
+        __skb_pull(skb, skb_network_header_len(skb));
         if (opt && opt->opt_flen)
                 ipv6_push_frag_opts(skb, opt, &proto);
         if (opt && opt->opt_nflen)
diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c
index 07e86ebb46b8..4c45bcce75e8 100644
--- a/net/ipv6/mcast.c
+++ b/net/ipv6/mcast.c
@@ -1168,7 +1168,7 @@ int igmp6_event_query(struct sk_buff *skb)
 
         /* compute payload length excluding extension headers */
         len = ntohs(ipv6_hdr(skb)->payload_len) + sizeof(struct ipv6hdr);
-        len -= skb->h.raw - skb->nh.raw;
+        len -= skb_network_header_len(skb);
 
         /* Drop queries with not link local source */
         if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL))
diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c
index 84ce5b3c4b21..490e7e151f2d 100644
--- a/net/ipv6/netfilter/nf_conntrack_reasm.c
+++ b/net/ipv6/netfilter/nf_conntrack_reasm.c
@@ -657,7 +657,7 @@ nf_ct_frag6_reasm(struct nf_ct_frag6_queue *fq, struct net_device *dev)
         /* Yes, and fold redundant checksum back. 8) */
         if (head->ip_summed == CHECKSUM_COMPLETE)
                 head->csum = csum_partial(skb_network_header(head),
-                                          head->h.raw - head->nh.raw,
+                                          skb_network_header_len(head),
                                           head->csum);
 
         fq->fragments = NULL;
diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index 116257d59a36..f925ca7c1a50 100644
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -362,7 +362,7 @@ int rawv6_rcv(struct sock *sk, struct sk_buff *skb)
 
         if (skb->ip_summed == CHECKSUM_COMPLETE) {
                 skb_postpull_rcsum(skb, skb_network_header(skb),
-                                   skb->h.raw - skb->nh.raw);
+                                   skb_network_header_len(skb));
                 if (!csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
                                      &ipv6_hdr(skb)->daddr,
                                      skb->len, inet->num, skb->csum))
diff --git a/net/ipv6/reassembly.c b/net/ipv6/reassembly.c
index 31d4271ea540..6dfacfa7a599 100644
--- a/net/ipv6/reassembly.c
+++ b/net/ipv6/reassembly.c
@@ -679,7 +679,7 @@ static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff **skb_in,
         /* Yes, and fold redundant checksum back. 8) */
         if (head->ip_summed == CHECKSUM_COMPLETE)
                 head->csum = csum_partial(skb_network_header(head),
-                                          head->h.raw - head->nh.raw,
+                                          skb_network_header_len(head),
                                           head->csum);
 
         rcu_read_lock();
@@ -715,13 +715,15 @@ static int ipv6_frag_rcv(struct sk_buff **skbp)
         /* Jumbo payload inhibits frag. header */
         if (hdr->payload_len==0) {
                 IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_INHDRERRORS);
-                icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, skb->h.raw-skb->nh.raw);
+                icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
+                                  skb_network_header_len(skb));
                 return -1;
         }
         if (!pskb_may_pull(skb, (skb_transport_offset(skb) +
                                  sizeof(struct frag_hdr)))) {
                 IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_INHDRERRORS);
-                icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, skb->h.raw-skb->nh.raw);
+                icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
+                                  skb_network_header_len(skb));
                 return -1;
         }
 
diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c
index b93bfb87f494..ef746d4f3131 100644
--- a/net/ipv6/xfrm6_policy.c
+++ b/net/ipv6/xfrm6_policy.c
@@ -270,7 +270,7 @@ error:
 static inline void
 _decode_session6(struct sk_buff *skb, struct flowi *fl)
 {
-        u16 offset = skb->h.raw - skb->nh.raw;
+        u16 offset = skb_network_header_len(skb);
         struct ipv6hdr *hdr = ipv6_hdr(skb);
         struct ipv6_opt_hdr *exthdr;
         const unsigned char *nh = skb_network_header(skb);