[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, 8 insertions, 38 deletions

diff --git a/include/net/tcp.h b/include/net/tcp.h
index 6663086a5e35..a2e323c54457 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -1686,71 +1686,41 @@ static inline int tcp_full_space(const struct sock *sk)
 static inline void tcp_acceptq_queue(struct sock *sk, struct request_sock *req,
                                          struct sock *child)
 {
-        struct tcp_sock *tp = tcp_sk(sk);
-
-        req->sk = child;
-        sk_acceptq_added(sk);
-
-        if (!tp->accept_queue_tail) {
-                tp->accept_queue = req;
-        } else {
-                tp->accept_queue_tail->dl_next = req;
-        }
-        tp->accept_queue_tail = req;
-        req->dl_next = NULL;
+        reqsk_queue_add(&tcp_sk(sk)->accept_queue, req, sk, child);
 }
 
-struct tcp_listen_opt
-{
-        u8                      max_qlen_log;   /* log_2 of maximal queued SYNs */
-        int                     qlen;
-        int                     qlen_young;
-        int                     clock_hand;
-        u32                     hash_rnd;
-        struct request_sock     *syn_table[TCP_SYNQ_HSIZE];
-};
-
 static inline void
 tcp_synq_removed(struct sock *sk, struct request_sock *req)
 {
-        struct tcp_listen_opt *lopt = tcp_sk(sk)->listen_opt;
-
-        if (--lopt->qlen == 0)
+        if (reqsk_queue_removed(&tcp_sk(sk)->accept_queue, req) == 0)
                 tcp_delete_keepalive_timer(sk);
-        if (req->retrans == 0)
-                lopt->qlen_young--;
 }
 
 static inline void tcp_synq_added(struct sock *sk)
 {
-        struct tcp_listen_opt *lopt = tcp_sk(sk)->listen_opt;
-
-        if (lopt->qlen++ == 0)
+        if (reqsk_queue_added(&tcp_sk(sk)->accept_queue) == 0)
                 tcp_reset_keepalive_timer(sk, TCP_TIMEOUT_INIT);
-        lopt->qlen_young++;
 }
 
 static inline int tcp_synq_len(struct sock *sk)
 {
-        return tcp_sk(sk)->listen_opt->qlen;
+        return reqsk_queue_len(&tcp_sk(sk)->accept_queue);
 }
 
 static inline int tcp_synq_young(struct sock *sk)
 {
-        return tcp_sk(sk)->listen_opt->qlen_young;
+        return reqsk_queue_len_young(&tcp_sk(sk)->accept_queue);
 }
 
 static inline int tcp_synq_is_full(struct sock *sk)
 {
-        return tcp_synq_len(sk) >> tcp_sk(sk)->listen_opt->max_qlen_log;
+        return reqsk_queue_is_full(&tcp_sk(sk)->accept_queue);
 }
 
 static inline void tcp_synq_unlink(struct tcp_sock *tp, struct request_sock *req,
-                                       struct request_sock **prev)
+                                   struct request_sock **prev)
 {
-        write_lock(&tp->syn_wait_lock);
-        *prev = req->dl_next;
-        write_unlock(&tp->syn_wait_lock);
+        reqsk_queue_unlink(&tp->accept_queue, req, prev);
 }
 
 static inline void tcp_synq_drop(struct sock *sk, struct request_sock *req,