[NET] Generalise tcp_listen_opt

This chunks out the accept_queue and tcp_listen_opt code and moves
them to net/core/request_sock.c and include/net/request_sock.h, to
make it useful for other transport protocols, DCCP being the first one
to use it.

Next patches will rename tcp_listen_opt to accept_sock and remove the
inline tcp functions that just call a reqsk_queue_ function.

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

1 files changed, 3 insertions, 7 deletions

diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c
index f03efe5fb76a..d97d191149c1 100644
--- a/net/ipv4/tcp_timer.c
+++ b/net/ipv4/tcp_timer.c
@@ -464,7 +464,7 @@ out_unlock:
 static void tcp_synack_timer(struct sock *sk)
 {
         struct tcp_sock *tp = tcp_sk(sk);
-        struct tcp_listen_opt *lopt = tp->listen_opt;
+        struct tcp_listen_opt *lopt = tp->accept_queue.listen_opt;
         int max_retries = tp->syn_retries ? : sysctl_tcp_synack_retries;
         int thresh = max_retries;
         unsigned long now = jiffies;
@@ -527,12 +527,8 @@ static void tcp_synack_timer(struct sock *sk)
                                 }
 
                                 /* Drop this request */
-                                write_lock(&tp->syn_wait_lock);
-                                *reqp = req->dl_next;
-                                write_unlock(&tp->syn_wait_lock);
-                                lopt->qlen--;
-                                if (req->retrans == 0)
-                                        lopt->qlen_young--;
+                                tcp_synq_unlink(tp, req, reqp);
+                                reqsk_queue_removed(&tp->accept_queue, req);
                                 reqsk_free(req);
                                 continue;
                         }