[SK_BUFF]: Introduce skb_transport_header(skb)

For the places where we need a pointer to the transport header, it is
still legal to touch skb->h.raw directly if just adding to,
subtracting from or setting it to another layer header.

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

1 files changed, 7 insertions, 6 deletions

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index c1ce36237380..9c3b4c7a50ad 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -140,7 +140,7 @@ static void tcp_measure_rcv_mss(struct sock *sk,
                  *
                  * "len" is invariant segment length, including TCP header.
                  */
-                len += skb->data - skb->h.raw;
+                len += skb->data - skb_transport_header(skb);
                 if (len >= TCP_MIN_RCVMSS + sizeof(struct tcphdr) ||
                     /* If PSH is not set, packet should be
                      * full sized, provided peer TCP is not badly broken.
@@ -940,7 +940,8 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_
 {
         const struct inet_connection_sock *icsk = inet_csk(sk);
         struct tcp_sock *tp = tcp_sk(sk);
-        unsigned char *ptr = ack_skb->h.raw + TCP_SKB_CB(ack_skb)->sacked;
+        unsigned char *ptr = (skb_transport_header(ack_skb) +
+                              TCP_SKB_CB(ack_skb)->sacked);
         struct tcp_sack_block_wire *sp = (struct tcp_sack_block_wire *)(ptr+2);
         struct sk_buff *cached_skb;
         int num_sacks = (ptr[1] - TCPOLEN_SACK_BASE)>>3;
@@ -3634,10 +3635,10 @@ tcp_collapse(struct sock *sk, struct sk_buff_head *list,
                         return;
 
                 skb_set_mac_header(nskb, skb_mac_header(skb) - skb->head);
-                skb_set_network_header(nskb,
-                                       skb_network_header(skb) - skb->head);
-                skb_set_transport_header(nskb, skb->h.raw - skb->head);
-
+                skb_set_network_header(nskb, (skb_network_header(skb) -
+                                              skb->head));
+                skb_set_transport_header(nskb, (skb_transport_header(skb) -
+                                                skb->head));
                 skb_reserve(nskb, header);
                 memcpy(nskb->head, skb->head, header);
                 memcpy(nskb->cb, skb->cb, sizeof(skb->cb));