[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, 12 insertions, 20 deletions

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 95528a75a63d..1745dc8d25e6 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -874,7 +874,7 @@ static struct request_sock *tcp_v4_search_req(struct tcp_sock *tp,
                                               __u16 rport,
                                               __u32 raddr, __u32 laddr)
 {
-        struct tcp_listen_opt *lopt = tp->listen_opt;
+        struct tcp_listen_opt *lopt = tp->accept_queue.listen_opt;
         struct request_sock *req, **prev;
 
         for (prev = &lopt->syn_table[tcp_v4_synq_hash(raddr, rport, lopt->hash_rnd)];
@@ -898,18 +898,10 @@ static struct request_sock *tcp_v4_search_req(struct tcp_sock *tp,
 static void tcp_v4_synq_add(struct sock *sk, struct request_sock *req)
 {
         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;
         u32 h = tcp_v4_synq_hash(inet_rsk(req)->rmt_addr, inet_rsk(req)->rmt_port, lopt->hash_rnd);
 
-        req->expires = jiffies + TCP_TIMEOUT_INIT;
-        req->retrans = 0;
-        req->sk = NULL;
-        req->dl_next = lopt->syn_table[h];
-
-        write_lock(&tp->syn_wait_lock);
-        lopt->syn_table[h] = req;
-        write_unlock(&tp->syn_wait_lock);
-
+        reqsk_queue_hash_req(&tp->accept_queue, h, req, TCP_TIMEOUT_INIT);
         tcp_synq_added(sk);
 }
 
@@ -2167,17 +2159,17 @@ static void *listening_get_next(struct seq_file *seq, void *cur)
                         if (++st->sbucket >= TCP_SYNQ_HSIZE)
                                 break;
 get_req:
-                        req = tp->listen_opt->syn_table[st->sbucket];
+                        req = tp->accept_queue.listen_opt->syn_table[st->sbucket];
                 }
                 sk        = sk_next(st->syn_wait_sk);
                 st->state = TCP_SEQ_STATE_LISTENING;
-                read_unlock_bh(&tp->syn_wait_lock);
+                read_unlock_bh(&tp->accept_queue.syn_wait_lock);
         } else {
                 tp = tcp_sk(sk);
-                read_lock_bh(&tp->syn_wait_lock);
-                if (tp->listen_opt && tp->listen_opt->qlen)
+                read_lock_bh(&tp->accept_queue.syn_wait_lock);
+                if (reqsk_queue_len(&tp->accept_queue))
                         goto start_req;
-                read_unlock_bh(&tp->syn_wait_lock);
+                read_unlock_bh(&tp->accept_queue.syn_wait_lock);
                 sk = sk_next(sk);
         }
 get_sk:
@@ -2187,8 +2179,8 @@ get_sk:
                         goto out;
                 }
                 tp = tcp_sk(sk);
-                read_lock_bh(&tp->syn_wait_lock);
-                if (tp->listen_opt && tp->listen_opt->qlen) {
+                read_lock_bh(&tp->accept_queue.syn_wait_lock);
+                if (reqsk_queue_len(&tp->accept_queue)) {
 start_req:
                         st->uid         = sock_i_uid(sk);
                         st->syn_wait_sk = sk;
@@ -2196,7 +2188,7 @@ start_req:
                         st->sbucket     = 0;
                         goto get_req;
                 }
-                read_unlock_bh(&tp->syn_wait_lock);
+                read_unlock_bh(&tp->accept_queue.syn_wait_lock);
         }
         if (++st->bucket < TCP_LHTABLE_SIZE) {
                 sk = sk_head(&tcp_listening_hash[st->bucket]);
@@ -2383,7 +2375,7 @@ static void tcp_seq_stop(struct seq_file *seq, void *v)
         case TCP_SEQ_STATE_OPENREQ:
                 if (v) {
                         struct tcp_sock *tp = tcp_sk(st->syn_wait_sk);
-                        read_unlock_bh(&tp->syn_wait_lock);
+                        read_unlock_bh(&tp->accept_queue.syn_wait_lock);
                 }
         case TCP_SEQ_STATE_LISTENING:
                 if (v != SEQ_START_TOKEN)