[NET]: Generalise TSO-specific bits from skb_setup_caps

This patch generalises the TSO-specific bits from sk_setup_caps by adding
the sk_gso_type member to struct sock.  This makes sk_setup_caps generic
so that it can be used by TCPv6 or UFO.

The only catch is that whoever uses this must provide a GSO implementation
for their protocol which I think is a fair deal :) For now UFO continues to
live without a GSO implementation which is OK since it doesn't use the sock
caps field at the moment.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 6 insertions, 7 deletions

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index b7cf26e0e5c2..59e30bab0606 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -643,7 +643,7 @@ static inline int select_size(struct sock *sk, struct tcp_sock *tp)
         int tmp = tp->mss_cache;
 
         if (sk->sk_route_caps & NETIF_F_SG) {
-                if (sk->sk_route_caps & NETIF_F_TSO)
+                if (sk_can_gso(sk))
                         tmp = 0;
                 else {
                         int pgbreak = SKB_MAX_HEAD(MAX_TCP_HEADER);
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 4c6ef47eb1c3..38e001076a5f 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -242,6 +242,7 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
                 goto failure;
 
         /* OK, now commit destination to socket.  */
+        sk->sk_gso_type = SKB_GSO_TCPV4;
         sk_setup_caps(sk, &rt->u.dst);
 
         if (!tp->write_seq)
@@ -884,6 +885,7 @@ struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
         if (!newsk)
                 goto exit;
 
+        newsk->sk_gso_type = SKB_GSO_TCPV4;
         sk_setup_caps(newsk, dst);
 
         newtp                 = tcp_sk(newsk);
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 5a7cb4a9c867..5c08ea20a18d 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -510,8 +510,7 @@ static void tcp_queue_skb(struct sock *sk, struct sk_buff *skb)
 
 static void tcp_set_skb_tso_segs(struct sock *sk, struct sk_buff *skb, unsigned int mss_now)
 {
-        if (skb->len <= mss_now ||
-            !(sk->sk_route_caps & NETIF_F_TSO)) {
+        if (skb->len <= mss_now || !sk_can_gso(sk)) {
                 /* Avoid the costly divide in the normal
                  * non-TSO case.
                  */
@@ -525,7 +524,7 @@ static void tcp_set_skb_tso_segs(struct sock *sk, struct sk_buff *skb, unsigned
                 factor /= mss_now;
                 skb_shinfo(skb)->gso_segs = factor;
                 skb_shinfo(skb)->gso_size = mss_now;
-                skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
+                skb_shinfo(skb)->gso_type = sk->sk_gso_type;
         }
 }
 
@@ -824,9 +823,7 @@ unsigned int tcp_current_mss(struct sock *sk, int large_allowed)
 
         mss_now = tp->mss_cache;
 
-        if (large_allowed &&
-            (sk->sk_route_caps & NETIF_F_TSO) &&
-            !tp->urg_mode)
+        if (large_allowed && sk_can_gso(sk) && !tp->urg_mode)
                 doing_tso = 1;
 
         if (dst) {