net/rose/rose_timer.c

   1 /*
   2  * This program is free software; you can redistribute it and/or modify
   3  * it under the terms of the GNU General Public License as published by
   4  * the Free Software Foundation; either version 2 of the License, or
   5  * (at your option) any later version.
   6  *
   7  * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
   8  * Copyright (C) 2002 Ralf Baechle DO1GRB (ralf@gnu.org)
   9  */
  10 #include <linux/errno.h>
  11 #include <linux/types.h>
  12 #include <linux/socket.h>
  13 #include <linux/in.h>
  14 #include <linux/kernel.h>
  15 #include <linux/jiffies.h>
  16 #include <linux/timer.h>
  17 #include <linux/string.h>
  18 #include <linux/sockios.h>
  19 #include <linux/net.h>
  20 #include <net/ax25.h>
  21 #include <linux/inet.h>
  22 #include <linux/netdevice.h>
  23 #include <linux/skbuff.h>
  24 #include <net/sock.h>
  25 #include <net/tcp_states.h>
  26 #include <linux/fcntl.h>
  27 #include <linux/mm.h>
  28 #include <linux/interrupt.h>
  29 #include <net/rose.h>
  30
  31 static void rose_heartbeat_expiry(struct timer_list *t);
  32 static void rose_timer_expiry(struct timer_list *);
  33 static void rose_idletimer_expiry(struct timer_list *);
  34
  35 void rose_start_heartbeat(struct sock *sk)
  36 {
  37         del_timer(&sk->sk_timer);
  38
  39         sk->sk_timer.function = rose_heartbeat_expiry;
  40         sk->sk_timer.expires  = jiffies + 5 * HZ;
  41
  42         add_timer(&sk->sk_timer);
  43 }
  44
  45 void rose_start_t1timer(struct sock *sk)
  46 {
  47         struct rose_sock *rose = rose_sk(sk);
  48
  49         del_timer(&rose->timer);
  50
  51         rose->timer.function = rose_timer_expiry;
  52         rose->timer.expires  = jiffies + rose->t1;
  53
  54         add_timer(&rose->timer);
  55 }
  56
  57 void rose_start_t2timer(struct sock *sk)
  58 {
  59         struct rose_sock *rose = rose_sk(sk);
  60
  61         del_timer(&rose->timer);
  62
  63         rose->timer.function = rose_timer_expiry;
  64         rose->timer.expires  = jiffies + rose->t2;
  65
  66         add_timer(&rose->timer);
  67 }
  68
  69 void rose_start_t3timer(struct sock *sk)
  70 {
  71         struct rose_sock *rose = rose_sk(sk);
  72
  73         del_timer(&rose->timer);
  74
  75         rose->timer.function = rose_timer_expiry;
  76         rose->timer.expires  = jiffies + rose->t3;
  77
  78         add_timer(&rose->timer);
  79 }
  80
  81 void rose_start_hbtimer(struct sock *sk)
  82 {
  83         struct rose_sock *rose = rose_sk(sk);
  84
  85         del_timer(&rose->timer);
  86
  87         rose->timer.function = rose_timer_expiry;
  88         rose->timer.expires  = jiffies + rose->hb;
  89
  90         add_timer(&rose->timer);
  91 }
  92
  93 void rose_start_idletimer(struct sock *sk)
  94 {
  95         struct rose_sock *rose = rose_sk(sk);
  96
  97         del_timer(&rose->idletimer);
  98
  99         if (rose->idle > 0) {
 100                 rose->idletimer.function = rose_idletimer_expiry;
 101                 rose->idletimer.expires  = jiffies + rose->idle;
 102
 103                 add_timer(&rose->idletimer);
 104         }
 105 }
 106
 107 void rose_stop_heartbeat(struct sock *sk)
 108 {
 109         del_timer(&sk->sk_timer);
 110 }
 111
 112 void rose_stop_timer(struct sock *sk)
 113 {
 114         del_timer(&rose_sk(sk)->timer);
 115 }
 116
 117 void rose_stop_idletimer(struct sock *sk)
 118 {
 119         del_timer(&rose_sk(sk)->idletimer);
 120 }
 121
 122 static void rose_heartbeat_expiry(struct timer_list *t)
 123 {
 124         struct sock *sk = from_timer(sk, t, sk_timer);
 125         struct rose_sock *rose = rose_sk(sk);
 126
 127         bh_lock_sock(sk);
 128         switch (rose->state) {
 129         case ROSE_STATE_0:
 130                 /* Magic here: If we listen() and a new link dies before it
 131                    is accepted() it isn't 'dead' so doesn't get removed. */
 132                 if (sock_flag(sk, SOCK_DESTROY) ||
 133                     (sk->sk_state == TCP_LISTEN && sock_flag(sk, SOCK_DEAD))) {
 134                         bh_unlock_sock(sk);
 135                         rose_destroy_socket(sk);
 136                         return;
 137                 }
 138                 break;
 139
 140         case ROSE_STATE_3:
 141                 /*
 142                  * Check for the state of the receive buffer.
 143                  */
 144                 if (atomic_read(&sk->sk_rmem_alloc) < (sk->sk_rcvbuf / 2) &&
 145                     (rose->condition & ROSE_COND_OWN_RX_BUSY)) {
 146                         rose->condition &= ~ROSE_COND_OWN_RX_BUSY;
 147                         rose->condition &= ~ROSE_COND_ACK_PENDING;
 148                         rose->vl         = rose->vr;
 149                         rose_write_internal(sk, ROSE_RR);
 150                         rose_stop_timer(sk);    /* HB */
 151                         break;
 152                 }
 153                 break;
 154         }
 155
 156         rose_start_heartbeat(sk);
 157         bh_unlock_sock(sk);
 158 }
 159
 160 static void rose_timer_expiry(struct timer_list *t)
 161 {
 162         struct rose_sock *rose = from_timer(rose, t, timer);
 163         struct sock *sk = &rose->sock;
 164
 165         bh_lock_sock(sk);
 166         switch (rose->state) {
 167         case ROSE_STATE_1:      /* T1 */
 168         case ROSE_STATE_4:      /* T2 */
 169                 rose_write_internal(sk, ROSE_CLEAR_REQUEST);
 170                 rose->state = ROSE_STATE_2;
 171                 rose_start_t3timer(sk);
 172                 break;
 173
 174         case ROSE_STATE_2:      /* T3 */
 175                 rose->neighbour->use--;
 176                 rose_disconnect(sk, ETIMEDOUT, -1, -1);
 177                 break;
 178
 179         case ROSE_STATE_3:      /* HB */
 180                 if (rose->condition & ROSE_COND_ACK_PENDING) {
 181                         rose->condition &= ~ROSE_COND_ACK_PENDING;
 182                         rose_enquiry_response(sk);
 183                 }
 184                 break;
 185         }
 186         bh_unlock_sock(sk);
 187 }
 188
 189 static void rose_idletimer_expiry(struct timer_list *t)
 190 {
 191         struct rose_sock *rose = from_timer(rose, t, idletimer);
 192         struct sock *sk = &rose->sock;
 193
 194         bh_lock_sock(sk);
 195         rose_clear_queues(sk);
 196
 197         rose_write_internal(sk, ROSE_CLEAR_REQUEST);
 198         rose_sk(sk)->state = ROSE_STATE_2;
 199
 200         rose_start_t3timer(sk);
 201
 202         sk->sk_state     = TCP_CLOSE;
 203         sk->sk_err       = 0;
 204         sk->sk_shutdown |= SEND_SHUTDOWN;
 205
 206         if (!sock_flag(sk, SOCK_DEAD)) {
 207                 sk->sk_state_change(sk);
 208                 sock_set_flag(sk, SOCK_DEAD);
 209         }
 210         bh_unlock_sock(sk);
 211 }