Fedora kernel-2.6.17-1.2142_FC4 patched with stable patch-2.6.17.4-vs2.0.2-rc26.diff
[linux-2.6.git] / net / ipv4 / tcp_timer.c
index 799ebe0..7c1bde3 100644 (file)
@@ -36,49 +36,13 @@ static void tcp_write_timer(unsigned long);
 static void tcp_delack_timer(unsigned long);
 static void tcp_keepalive_timer (unsigned long data);
 
-#ifdef TCP_DEBUG
-const char tcp_timer_bug_msg[] = KERN_DEBUG "tcpbug: unknown timer value\n";
-EXPORT_SYMBOL(tcp_timer_bug_msg);
-#endif
-
-/*
- * Using different timers for retransmit, delayed acks and probes
- * We may wish use just one timer maintaining a list of expire jiffies 
- * to optimize.
- */
-
 void tcp_init_xmit_timers(struct sock *sk)
 {
-       struct tcp_sock *tp = tcp_sk(sk);
-
-       init_timer(&tp->retransmit_timer);
-       tp->retransmit_timer.function=&tcp_write_timer;
-       tp->retransmit_timer.data = (unsigned long) sk;
-       tp->pending = 0;
-
-       init_timer(&tp->delack_timer);
-       tp->delack_timer.function=&tcp_delack_timer;
-       tp->delack_timer.data = (unsigned long) sk;
-       tp->ack.pending = 0;
-
-       init_timer(&sk->sk_timer);
-       sk->sk_timer.function   = &tcp_keepalive_timer;
-       sk->sk_timer.data       = (unsigned long)sk;
+       inet_csk_init_xmit_timers(sk, &tcp_write_timer, &tcp_delack_timer,
+                                 &tcp_keepalive_timer);
 }
 
-void tcp_clear_xmit_timers(struct sock *sk)
-{
-       struct tcp_sock *tp = tcp_sk(sk);
-
-       tp->pending = 0;
-       sk_stop_timer(sk, &tp->retransmit_timer);
-
-       tp->ack.pending = 0;
-       tp->ack.blocked = 0;
-       sk_stop_timer(sk, &tp->delack_timer);
-
-       sk_stop_timer(sk, &sk->sk_timer);
-}
+EXPORT_SYMBOL(tcp_init_xmit_timers);
 
 static void tcp_write_err(struct sock *sk)
 {
@@ -94,7 +58,7 @@ static void tcp_write_err(struct sock *sk)
  * to prevent DoS attacks. It is called when a retransmission timeout
  * or zero probe timeout occurs on orphaned socket.
  *
- * Criterium is still not confirmed experimentally and may change.
+ * Criteria is still not confirmed experimentally and may change.
  * We kill the socket, if:
  * 1. If number of orphaned sockets exceeds an administratively configured
  *    limit.
@@ -155,50 +119,46 @@ static int tcp_orphan_retries(struct sock *sk, int alive)
 /* A write timeout has occurred. Process the after effects. */
 static int tcp_write_timeout(struct sock *sk)
 {
+       struct inet_connection_sock *icsk = inet_csk(sk);
        struct tcp_sock *tp = tcp_sk(sk);
        int retry_until;
+       int mss;
 
        if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV)) {
-               if (tp->retransmits)
+               if (icsk->icsk_retransmits)
                        dst_negative_advice(&sk->sk_dst_cache);
-               retry_until = tp->syn_retries ? : sysctl_tcp_syn_retries;
+               retry_until = icsk->icsk_syn_retries ? : sysctl_tcp_syn_retries;
        } else {
-               if (tp->retransmits >= sysctl_tcp_retries1) {
-                       /* NOTE. draft-ietf-tcpimpl-pmtud-01.txt requires pmtu black
-                          hole detection. :-(
-
-                          It is place to make it. It is not made. I do not want
-                          to make it. It is disguisting. It does not work in any
-                          case. Let me to cite the same draft, which requires for
-                          us to implement this:
-
-   "The one security concern raised by this memo is that ICMP black holes
-   are often caused by over-zealous security administrators who block
-   all ICMP messages.  It is vitally important that those who design and
-   deploy security systems understand the impact of strict filtering on
-   upper-layer protocols.  The safest web site in the world is worthless
-   if most TCP implementations cannot transfer data from it.  It would
-   be far nicer to have all of the black holes fixed rather than fixing
-   all of the TCP implementations."
-
-                           Golden words :-).
-                  */
+               if (icsk->icsk_retransmits >= sysctl_tcp_retries1) {
+                       /* Black hole detection */
+                       if (sysctl_tcp_mtu_probing) {
+                               if (!icsk->icsk_mtup.enabled) {
+                                       icsk->icsk_mtup.enabled = 1;
+                                       tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);
+                               } else {
+                                       mss = min(sysctl_tcp_base_mss,
+                                                 tcp_mtu_to_mss(sk, icsk->icsk_mtup.search_low)/2);
+                                       mss = max(mss, 68 - tp->tcp_header_len);
+                                       icsk->icsk_mtup.search_low = tcp_mss_to_mtu(sk, mss);
+                                       tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);
+                               }
+                       }
 
                        dst_negative_advice(&sk->sk_dst_cache);
                }
 
                retry_until = sysctl_tcp_retries2;
                if (sock_flag(sk, SOCK_DEAD)) {
-                       int alive = (tp->rto < TCP_RTO_MAX);
+                       const int alive = (icsk->icsk_rto < TCP_RTO_MAX);
  
                        retry_until = tcp_orphan_retries(sk, alive);
 
-                       if (tcp_out_of_resources(sk, alive || tp->retransmits < retry_until))
+                       if (tcp_out_of_resources(sk, alive || icsk->icsk_retransmits < retry_until))
                                return 1;
                }
        }
 
-       if (tp->retransmits >= retry_until) {
+       if (icsk->icsk_retransmits >= retry_until) {
                /* Has it gone just too far? */
                tcp_write_err(sk);
                return 1;
@@ -210,32 +170,32 @@ static void tcp_delack_timer(unsigned long data)
 {
        struct sock *sk = (struct sock*)data;
        struct tcp_sock *tp = tcp_sk(sk);
+       struct inet_connection_sock *icsk = inet_csk(sk);
 
        bh_lock_sock(sk);
        if (sock_owned_by_user(sk)) {
                /* Try again later. */
-               tp->ack.blocked = 1;
+               icsk->icsk_ack.blocked = 1;
                NET_INC_STATS_BH(LINUX_MIB_DELAYEDACKLOCKED);
-               sk_reset_timer(sk, &tp->delack_timer, jiffies + TCP_DELACK_MIN);
+               sk_reset_timer(sk, &icsk->icsk_delack_timer, jiffies + TCP_DELACK_MIN);
                goto out_unlock;
        }
 
        sk_stream_mem_reclaim(sk);
 
-       if (sk->sk_state == TCP_CLOSE || !(tp->ack.pending & TCP_ACK_TIMER))
+       if (sk->sk_state == TCP_CLOSE || !(icsk->icsk_ack.pending & ICSK_ACK_TIMER))
                goto out;
 
-       if (time_after(tp->ack.timeout, jiffies)) {
-               sk_reset_timer(sk, &tp->delack_timer, tp->ack.timeout);
+       if (time_after(icsk->icsk_ack.timeout, jiffies)) {
+               sk_reset_timer(sk, &icsk->icsk_delack_timer, icsk->icsk_ack.timeout);
                goto out;
        }
-       tp->ack.pending &= ~TCP_ACK_TIMER;
+       icsk->icsk_ack.pending &= ~ICSK_ACK_TIMER;
 
-       if (skb_queue_len(&tp->ucopy.prequeue)) {
+       if (!skb_queue_empty(&tp->ucopy.prequeue)) {
                struct sk_buff *skb;
 
-               NET_ADD_STATS_BH(LINUX_MIB_TCPSCHEDULERFAILED, 
-                                skb_queue_len(&tp->ucopy.prequeue));
+               NET_INC_STATS_BH(LINUX_MIB_TCPSCHEDULERFAILED);
 
                while ((skb = __skb_dequeue(&tp->ucopy.prequeue)) != NULL)
                        sk->sk_backlog_rcv(sk, skb);
@@ -243,16 +203,16 @@ static void tcp_delack_timer(unsigned long data)
                tp->ucopy.memory = 0;
        }
 
-       if (tcp_ack_scheduled(tp)) {
-               if (!tp->ack.pingpong) {
+       if (inet_csk_ack_scheduled(sk)) {
+               if (!icsk->icsk_ack.pingpong) {
                        /* Delayed ACK missed: inflate ATO. */
-                       tp->ack.ato = min(tp->ack.ato << 1, tp->rto);
+                       icsk->icsk_ack.ato = min(icsk->icsk_ack.ato << 1, icsk->icsk_rto);
                } else {
                        /* Delayed ACK missed: leave pingpong mode and
                         * deflate ATO.
                         */
-                       tp->ack.pingpong = 0;
-                       tp->ack.ato = TCP_ATO_MIN;
+                       icsk->icsk_ack.pingpong = 0;
+                       icsk->icsk_ack.ato      = TCP_ATO_MIN;
                }
                tcp_send_ack(sk);
                NET_INC_STATS_BH(LINUX_MIB_DELAYEDACKS);
@@ -269,11 +229,12 @@ out_unlock:
 
 static void tcp_probe_timer(struct sock *sk)
 {
+       struct inet_connection_sock *icsk = inet_csk(sk);
        struct tcp_sock *tp = tcp_sk(sk);
        int max_probes;
 
        if (tp->packets_out || !sk->sk_send_head) {
-               tp->probes_out = 0;
+               icsk->icsk_probes_out = 0;
                return;
        }
 
@@ -284,7 +245,7 @@ static void tcp_probe_timer(struct sock *sk)
         * FIXME: We ought not to do it, Solaris 2.5 actually has fixing
         * this behaviour in Solaris down as a bug fix. [AC]
         *
-        * Let me to explain. probes_out is zeroed by incoming ACKs
+        * Let me to explain. icsk_probes_out is zeroed by incoming ACKs
         * even if they advertise zero window. Hence, connection is killed only
         * if we received no ACKs for normal connection timeout. It is not killed
         * only because window stays zero for some time, window may be zero
@@ -295,15 +256,15 @@ static void tcp_probe_timer(struct sock *sk)
        max_probes = sysctl_tcp_retries2;
 
        if (sock_flag(sk, SOCK_DEAD)) {
-               int alive = ((tp->rto<<tp->backoff) < TCP_RTO_MAX);
+               const int alive = ((icsk->icsk_rto << icsk->icsk_backoff) < TCP_RTO_MAX);
  
                max_probes = tcp_orphan_retries(sk, alive);
 
-               if (tcp_out_of_resources(sk, alive || tp->probes_out <= max_probes))
+               if (tcp_out_of_resources(sk, alive || icsk->icsk_probes_out <= max_probes))
                        return;
        }
 
-       if (tp->probes_out > max_probes) {
+       if (icsk->icsk_probes_out > max_probes) {
                tcp_write_err(sk);
        } else {
                /* Only send another probe if we didn't close things up. */
@@ -318,6 +279,7 @@ static void tcp_probe_timer(struct sock *sk)
 static void tcp_retransmit_timer(struct sock *sk)
 {
        struct tcp_sock *tp = tcp_sk(sk);
+       struct inet_connection_sock *icsk = inet_csk(sk);
 
        if (!tp->packets_out)
                goto out;
@@ -352,20 +314,21 @@ static void tcp_retransmit_timer(struct sock *sk)
        if (tcp_write_timeout(sk))
                goto out;
 
-       if (tp->retransmits == 0) {
-               if (tp->ca_state == TCP_CA_Disorder || tp->ca_state == TCP_CA_Recovery) {
+       if (icsk->icsk_retransmits == 0) {
+               if (icsk->icsk_ca_state == TCP_CA_Disorder ||
+                   icsk->icsk_ca_state == TCP_CA_Recovery) {
                        if (tp->rx_opt.sack_ok) {
-                               if (tp->ca_state == TCP_CA_Recovery)
+                               if (icsk->icsk_ca_state == TCP_CA_Recovery)
                                        NET_INC_STATS_BH(LINUX_MIB_TCPSACKRECOVERYFAIL);
                                else
                                        NET_INC_STATS_BH(LINUX_MIB_TCPSACKFAILURES);
                        } else {
-                               if (tp->ca_state == TCP_CA_Recovery)
+                               if (icsk->icsk_ca_state == TCP_CA_Recovery)
                                        NET_INC_STATS_BH(LINUX_MIB_TCPRENORECOVERYFAIL);
                                else
                                        NET_INC_STATS_BH(LINUX_MIB_TCPRENOFAILURES);
                        }
-               } else if (tp->ca_state == TCP_CA_Loss) {
+               } else if (icsk->icsk_ca_state == TCP_CA_Loss) {
                        NET_INC_STATS_BH(LINUX_MIB_TCPLOSSFAILURES);
                } else {
                        NET_INC_STATS_BH(LINUX_MIB_TCPTIMEOUTS);
@@ -382,10 +345,11 @@ static void tcp_retransmit_timer(struct sock *sk)
                /* Retransmission failed because of local congestion,
                 * do not backoff.
                 */
-               if (!tp->retransmits)
-                       tp->retransmits=1;
-               tcp_reset_xmit_timer(sk, TCP_TIME_RETRANS,
-                                    min(tp->rto, TCP_RESOURCE_PROBE_INTERVAL));
+               if (!icsk->icsk_retransmits)
+                       icsk->icsk_retransmits = 1;
+               inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
+                                         min(icsk->icsk_rto, TCP_RESOURCE_PROBE_INTERVAL),
+                                         TCP_RTO_MAX);
                goto out;
        }
 
@@ -404,13 +368,13 @@ static void tcp_retransmit_timer(struct sock *sk)
         * implemented ftp to mars will work nicely. We will have to fix
         * the 120 second clamps though!
         */
-       tp->backoff++;
-       tp->retransmits++;
+       icsk->icsk_backoff++;
+       icsk->icsk_retransmits++;
 
 out_reset_timer:
-       tp->rto = min(tp->rto << 1, TCP_RTO_MAX);
-       tcp_reset_xmit_timer(sk, TCP_TIME_RETRANS, tp->rto);
-       if (tp->retransmits > sysctl_tcp_retries1)
+       icsk->icsk_rto = min(icsk->icsk_rto << 1, TCP_RTO_MAX);
+       inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, icsk->icsk_rto, TCP_RTO_MAX);
+       if (icsk->icsk_retransmits > sysctl_tcp_retries1)
                __sk_dst_reset(sk);
 
 out:;
@@ -419,32 +383,32 @@ out:;
 static void tcp_write_timer(unsigned long data)
 {
        struct sock *sk = (struct sock*)data;
-       struct tcp_sock *tp = tcp_sk(sk);
+       struct inet_connection_sock *icsk = inet_csk(sk);
        int event;
 
        bh_lock_sock(sk);
        if (sock_owned_by_user(sk)) {
                /* Try again later */
-               sk_reset_timer(sk, &tp->retransmit_timer, jiffies + (HZ / 20));
+               sk_reset_timer(sk, &icsk->icsk_retransmit_timer, jiffies + (HZ / 20));
                goto out_unlock;
        }
 
-       if (sk->sk_state == TCP_CLOSE || !tp->pending)
+       if (sk->sk_state == TCP_CLOSE || !icsk->icsk_pending)
                goto out;
 
-       if (time_after(tp->timeout, jiffies)) {
-               sk_reset_timer(sk, &tp->retransmit_timer, tp->timeout);
+       if (time_after(icsk->icsk_timeout, jiffies)) {
+               sk_reset_timer(sk, &icsk->icsk_retransmit_timer, icsk->icsk_timeout);
                goto out;
        }
 
-       event = tp->pending;
-       tp->pending = 0;
+       event = icsk->icsk_pending;
+       icsk->icsk_pending = 0;
 
        switch (event) {
-       case TCP_TIME_RETRANS:
+       case ICSK_TIME_RETRANS:
                tcp_retransmit_timer(sk);
                break;
-       case TCP_TIME_PROBE0:
+       case ICSK_TIME_PROBE0:
                tcp_probe_timer(sk);
                break;
        }
@@ -463,100 +427,8 @@ 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;
-       int max_retries = tp->syn_retries ? : sysctl_tcp_synack_retries;
-       int thresh = max_retries;
-       unsigned long now = jiffies;
-       struct open_request **reqp, *req;
-       int i, budget;
-
-       if (lopt == NULL || lopt->qlen == 0)
-               return;
-
-       /* Normally all the openreqs are young and become mature
-        * (i.e. converted to established socket) for first timeout.
-        * If synack was not acknowledged for 3 seconds, it means
-        * one of the following things: synack was lost, ack was lost,
-        * rtt is high or nobody planned to ack (i.e. synflood).
-        * When server is a bit loaded, queue is populated with old
-        * open requests, reducing effective size of queue.
-        * When server is well loaded, queue size reduces to zero
-        * after several minutes of work. It is not synflood,
-        * it is normal operation. The solution is pruning
-        * too old entries overriding normal timeout, when
-        * situation becomes dangerous.
-        *
-        * Essentially, we reserve half of room for young
-        * embrions; and abort old ones without pity, if old
-        * ones are about to clog our table.
-        */
-       if (lopt->qlen>>(lopt->max_qlen_log-1)) {
-               int young = (lopt->qlen_young<<1);
-
-               while (thresh > 2) {
-                       if (lopt->qlen < young)
-                               break;
-                       thresh--;
-                       young <<= 1;
-               }
-       }
-
-       if (tp->defer_accept)
-               max_retries = tp->defer_accept;
-
-       budget = 2*(TCP_SYNQ_HSIZE/(TCP_TIMEOUT_INIT/TCP_SYNQ_INTERVAL));
-       i = lopt->clock_hand;
-
-       do {
-               reqp=&lopt->syn_table[i];
-               while ((req = *reqp) != NULL) {
-                       if (time_after_eq(now, req->expires)) {
-                               if ((req->retrans < thresh ||
-                                    (req->acked && req->retrans < max_retries))
-                                   && !req->class->rtx_syn_ack(sk, req, NULL)) {
-                                       unsigned long timeo;
-
-                                       if (req->retrans++ == 0)
-                                               lopt->qlen_young--;
-                                       timeo = min((TCP_TIMEOUT_INIT << req->retrans),
-                                                   TCP_RTO_MAX);
-                                       req->expires = now + timeo;
-                                       reqp = &req->dl_next;
-                                       continue;
-                               }
-
-                               /* 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_openreq_free(req);
-                               continue;
-                       }
-                       reqp = &req->dl_next;
-               }
-
-               i = (i+1)&(TCP_SYNQ_HSIZE-1);
-
-       } while (--budget > 0);
-
-       lopt->clock_hand = i;
-
-       if (lopt->qlen)
-               tcp_reset_keepalive_timer(sk, TCP_SYNQ_INTERVAL);
-}
-
-void tcp_delete_keepalive_timer (struct sock *sk)
-{
-       sk_stop_timer(sk, &sk->sk_timer);
-}
-
-void tcp_reset_keepalive_timer (struct sock *sk, unsigned long len)
-{
-       sk_reset_timer(sk, &sk->sk_timer, jiffies + len);
+       inet_csk_reqsk_queue_prune(sk, TCP_SYNQ_INTERVAL,
+                                  TCP_TIMEOUT_INIT, TCP_RTO_MAX);
 }
 
 void tcp_set_keepalive(struct sock *sk, int val)
@@ -565,15 +437,16 @@ void tcp_set_keepalive(struct sock *sk, int val)
                return;
 
        if (val && !sock_flag(sk, SOCK_KEEPOPEN))
-               tcp_reset_keepalive_timer(sk, keepalive_time_when(tcp_sk(sk)));
+               inet_csk_reset_keepalive_timer(sk, keepalive_time_when(tcp_sk(sk)));
        else if (!val)
-               tcp_delete_keepalive_timer(sk);
+               inet_csk_delete_keepalive_timer(sk);
 }
 
 
 static void tcp_keepalive_timer (unsigned long data)
 {
        struct sock *sk = (struct sock *) data;
+       struct inet_connection_sock *icsk = inet_csk(sk);
        struct tcp_sock *tp = tcp_sk(sk);
        __u32 elapsed;
 
@@ -581,7 +454,7 @@ static void tcp_keepalive_timer (unsigned long data)
        bh_lock_sock(sk);
        if (sock_owned_by_user(sk)) {
                /* Try again later. */ 
-               tcp_reset_keepalive_timer (sk, HZ/20);
+               inet_csk_reset_keepalive_timer (sk, HZ/20);
                goto out;
        }
 
@@ -592,7 +465,7 @@ static void tcp_keepalive_timer (unsigned long data)
 
        if (sk->sk_state == TCP_FIN_WAIT2 && sock_flag(sk, SOCK_DEAD)) {
                if (tp->linger2 >= 0) {
-                       int tmo = tcp_fin_time(tp) - TCP_TIMEWAIT_LEN;
+                       const int tmo = tcp_fin_time(sk) - TCP_TIMEWAIT_LEN;
 
                        if (tmo > 0) {
                                tcp_time_wait(sk, TCP_FIN_WAIT2, tmo);
@@ -615,14 +488,14 @@ static void tcp_keepalive_timer (unsigned long data)
        elapsed = tcp_time_stamp - tp->rcv_tstamp;
 
        if (elapsed >= keepalive_time_when(tp)) {
-               if ((!tp->keepalive_probes && tp->probes_out >= sysctl_tcp_keepalive_probes) ||
-                    (tp->keepalive_probes && tp->probes_out >= tp->keepalive_probes)) {
+               if ((!tp->keepalive_probes && icsk->icsk_probes_out >= sysctl_tcp_keepalive_probes) ||
+                    (tp->keepalive_probes && icsk->icsk_probes_out >= tp->keepalive_probes)) {
                        tcp_send_active_reset(sk, GFP_ATOMIC);
                        tcp_write_err(sk);
                        goto out;
                }
                if (tcp_write_wakeup(sk) <= 0) {
-                       tp->probes_out++;
+                       icsk->icsk_probes_out++;
                        elapsed = keepalive_intvl_when(tp);
                } else {
                        /* If keepalive was lost due to local congestion,
@@ -639,7 +512,7 @@ static void tcp_keepalive_timer (unsigned long data)
        sk_stream_mem_reclaim(sk);
 
 resched:
-       tcp_reset_keepalive_timer (sk, elapsed);
+       inet_csk_reset_keepalive_timer (sk, elapsed);
        goto out;
 
 death: 
@@ -649,8 +522,3 @@ out:
        bh_unlock_sock(sk);
        sock_put(sk);
 }
-
-EXPORT_SYMBOL(tcp_clear_xmit_timers);
-EXPORT_SYMBOL(tcp_delete_keepalive_timer);
-EXPORT_SYMBOL(tcp_init_xmit_timers);
-EXPORT_SYMBOL(tcp_reset_keepalive_timer);