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(unsigned long);
  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.data     = (unsigned long)sk;
  40         sk->sk_timer.function = &rose_heartbeat_expiry;
  41         sk->sk_timer.expires  = jiffies + 5 * HZ;
  42
  43         add_timer(&sk->sk_timer);
  44 }
  45
  46 void rose_start_t1timer(struct sock *sk)
  47 {
  48         struct rose_sock *rose = rose_sk(sk);
  49
  50         del_timer(&rose->timer);
  51
  52         rose->timer.function = (TIMER_FUNC_TYPE)rose_timer_expiry;
  53         rose->timer.expires  = jiffies + rose->t1;
  54
  55         add_timer(&rose->timer);
  56 }
  57
  58 void rose_start_t2timer(struct sock *sk)
  59 {
  60         struct rose_sock *rose = rose_sk(sk);
  61
  62         del_timer(&rose->timer);
  63
  64         rose->timer.function = (TIMER_FUNC_TYPE)rose_timer_expiry;
  65         rose->timer.expires  = jiffies + rose->t2;
  66
  67         add_timer(&rose->timer);
  68 }
  69
  70 void rose_start_t3timer(struct sock *sk)
  71 {
  72         struct rose_sock *rose = rose_sk(sk);
  73
  74         del_timer(&rose->timer);
  75
  76         rose->timer.function = (TIMER_FUNC_TYPE)rose_timer_expiry;
  77         rose->timer.expires  = jiffies + rose->t3;
  78
  79         add_timer(&rose->timer);
  80 }
  81
  82 void rose_start_hbtimer(struct sock *sk)
  83 {
  84         struct rose_sock *rose = rose_sk(sk);
  85
  86         del_timer(&rose->timer);
  87
  88         rose->timer.function = (TIMER_FUNC_TYPE)rose_timer_expiry;
  89         rose->timer.expires  = jiffies + rose->hb;
  90
  91         add_timer(&rose->timer);
  92 }
  93
  94 void rose_start_idletimer(struct sock *sk)
  95 {
  96         struct rose_sock *rose = rose_sk(sk);
  97
  98         del_timer(&rose->idletimer);
  99
 100         if (rose->idle > 0) {
 101                 rose->idletimer.function = (TIMER_FUNC_TYPE)rose_idletimer_expiry;
 102                 rose->idletimer.expires  = jiffies + rose->idle;
 103
 104                 add_timer(&rose->idletimer);
 105         }
 106 }
 107
 108 void rose_stop_heartbeat(struct sock *sk)
 109 {
 110         del_timer(&sk->sk_timer);
 111 }
 112
 113 void rose_stop_timer(struct sock *sk)
 114 {
 115         del_timer(&rose_sk(sk)->timer);
 116 }
 117
 118 void rose_stop_idletimer(struct sock *sk)
 119 {
 120         del_timer(&rose_sk(sk)->idletimer);
 121 }
 122
 123 static void rose_heartbeat_expiry(unsigned long param)
 124 {
 125         struct sock *sk = (struct sock *)param;
 126         struct rose_sock *rose = rose_sk(sk);
 127
 128         bh_lock_sock(sk);
 129         switch (rose->state) {
 130         case ROSE_STATE_0:
 131                 /* Magic here: If we listen() and a new link dies before it
 132                    is accepted() it isn't 'dead' so doesn't get removed. */
 133                 if (sock_flag(sk, SOCK_DESTROY) ||
 134                     (sk->sk_state == TCP_LISTEN && sock_flag(sk, SOCK_DEAD))) {
 135                         bh_unlock_sock(sk);
 136                         rose_destroy_socket(sk);
 137                         return;
 138                 }
 139                 break;
 140
 141         case ROSE_STATE_3:
 142                 /*
 143                  * Check for the state of the receive buffer.
 144                  */
 145                 if (atomic_read(&sk->sk_rmem_alloc) < (sk->sk_rcvbuf / 2) &&
 146                     (rose->condition & ROSE_COND_OWN_RX_BUSY)) {
 147                         rose->condition &= ~ROSE_COND_OWN_RX_BUSY;
 148                         rose->condition &= ~ROSE_COND_ACK_PENDING;
 149                         rose->vl         = rose->vr;
 150                         rose_write_internal(sk, ROSE_RR);
 151                         rose_stop_timer(sk);    /* HB */
 152                         break;
 153                 }
 154                 break;
 155         }
 156
 157         rose_start_heartbeat(sk);
 158         bh_unlock_sock(sk);
 159 }
 160
 161 static void rose_timer_expiry(struct timer_list *t)
 162 {
 163         struct rose_sock *rose = from_timer(rose, t, timer);
 164         struct sock *sk = &rose->sock;
 165
 166         bh_lock_sock(sk);
 167         switch (rose->state) {
 168         case ROSE_STATE_1:      /* T1 */
 169         case ROSE_STATE_4:      /* T2 */
 170                 rose_write_internal(sk, ROSE_CLEAR_REQUEST);
 171                 rose->state = ROSE_STATE_2;
 172                 rose_start_t3timer(sk);
 173                 break;
 174
 175         case ROSE_STATE_2:      /* T3 */
 176                 rose->neighbour->use--;
 177                 rose_disconnect(sk, ETIMEDOUT, -1, -1);
 178                 break;
 179
 180         case ROSE_STATE_3:      /* HB */
 181                 if (rose->condition & ROSE_COND_ACK_PENDING) {
 182                         rose->condition &= ~ROSE_COND_ACK_PENDING;
 183                         rose_enquiry_response(sk);
 184                 }
 185                 break;
 186         }
 187         bh_unlock_sock(sk);
 188 }
 189
 190 static void rose_idletimer_expiry(struct timer_list *t)
 191 {
 192         struct rose_sock *rose = from_timer(rose, t, idletimer);
 193         struct sock *sk = &rose->sock;
 194
 195         bh_lock_sock(sk);
 196         rose_clear_queues(sk);
 197
 198         rose_write_internal(sk, ROSE_CLEAR_REQUEST);
 199         rose_sk(sk)->state = ROSE_STATE_2;
 200
 201         rose_start_t3timer(sk);
 202
 203         sk->sk_state     = TCP_CLOSE;
 204         sk->sk_err       = 0;
 205         sk->sk_shutdown |= SEND_SHUTDOWN;
 206
 207         if (!sock_flag(sk, SOCK_DEAD)) {
 208                 sk->sk_state_change(sk);
 209                 sock_set_flag(sk, SOCK_DEAD);
 210         }
 211         bh_unlock_sock(sk);
 212 }