tcp: add send_synack method to tcp_request_sock_ops

Create a new tcp_request_sock_ops method to unify the IPv4/IPv6
signature for tcp_v[46]_send_synack. This allows us to later unify
tcp_v4_rtx_synack with tcp_v6_rtx_synack and tcp_v4_conn_request with
tcp_v4_conn_request.

Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 8 insertions, 6 deletions

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 2fd886fe8340..210b6105afed 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -470,13 +470,14 @@ out:
 
 
 static int tcp_v6_send_synack(struct sock *sk, struct dst_entry *dst,
-                              struct flowi6 *fl6,
+                              struct flowi *fl,
                               struct request_sock *req,
                               u16 queue_mapping,
                               struct tcp_fastopen_cookie *foc)
 {
         struct inet_request_sock *ireq = inet_rsk(req);
         struct ipv6_pinfo *np = inet6_sk(sk);
+        struct flowi6 *fl6 = &fl->u.ip6;
         struct sk_buff *skb;
         int err = -ENOMEM;
 
@@ -507,10 +508,11 @@ done:
 
 static int tcp_v6_rtx_synack(struct sock *sk, struct request_sock *req)
 {
-        struct flowi6 fl6;
+        const struct tcp_request_sock_ops *af_ops = tcp_rsk(req)->af_specific;
+        struct flowi fl;
         int res;
 
-        res = tcp_v6_send_synack(sk, NULL, &fl6, req, 0, NULL);
+        res = af_ops->send_synack(sk, NULL, &fl, req, 0, NULL);
         if (!res) {
                 TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_RETRANSSEGS);
                 NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPSYNRETRANS);
@@ -754,7 +756,6 @@ static struct dst_entry *tcp_v6_route_req(struct sock *sk, struct flowi *fl,
         return inet6_csk_route_req(sk, &fl->u.ip6, req);
 }
 
-
 struct request_sock_ops tcp6_request_sock_ops __read_mostly = {
         .family         =       AF_INET6,
         .obj_size       =       sizeof(struct tcp6_request_sock),
@@ -776,6 +777,7 @@ static const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = {
 #endif
         .route_req      =       tcp_v6_route_req,
         .init_seq       =       tcp_v6_init_sequence,
+        .send_synack    =       tcp_v6_send_synack,
 };
 
 static void tcp_v6_send_response(struct sk_buff *skb, u32 seq, u32 ack, u32 win,
@@ -1128,8 +1130,8 @@ static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
         tcp_openreq_init_rwin(req, sk, dst);
         fastopen = !want_cookie &&
                    tcp_try_fastopen(sk, skb, req, &foc, dst);
-        err = tcp_v6_send_synack(sk, dst, &fl6, req,
-                                 skb_get_queue_mapping(skb), &foc);
+        err = af_ops->send_synack(sk, dst, (struct flowi *)&fl6, req,
+                                  skb_get_queue_mapping(skb), &foc);
         if (!fastopen) {
                 if (err || want_cookie)
                         goto drop_and_free;