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 <asm/system.h>
  27 #include <linux/fcntl.h>
  28 #include <linux/mm.h>
  29 #include <linux/interrupt.h>
  30 #include <net/rose.h>
  31
  32 static void rose_heartbeat_expiry(unsigned long);
  33 static void rose_timer_expiry(unsigned long);
  34 static void rose_idletimer_expiry(unsigned long);
  35
  36 void rose_start_heartbeat(struct sock *sk)
  37 {
  38         del_timer(&sk->sk_timer);
  39
  40         sk->sk_timer.data     = (unsigned long)sk;
  41         sk->sk_timer.function = &rose_heartbeat_expiry;
  42         sk->sk_timer.expires  = jiffies + 5 * HZ;
  43
  44         add_timer(&sk->sk_timer);
  45 }
  46
  47 void rose_start_t1timer(struct sock *sk)
  48 {
  49         struct rose_sock *rose = rose_sk(sk);
  50
  51         del_timer(&rose->timer);
  52
  53         rose->timer.data     = (unsigned long)sk;
  54         rose->timer.function = &rose_timer_expiry;
  55         rose->timer.expires  = jiffies + rose->t1;
  56
  57         add_timer(&rose->timer);
  58 }
  59
  60 void rose_start_t2timer(struct sock *sk)
  61 {
  62         struct rose_sock *rose = rose_sk(sk);
  63
  64         del_timer(&rose->timer);
  65
  66         rose->timer.data     = (unsigned long)sk;
  67         rose->timer.function = &rose_timer_expiry;
  68         rose->timer.expires  = jiffies + rose->t2;
  69
  70         add_timer(&rose->timer);
  71 }
  72
  73 void rose_start_t3timer(struct sock *sk)
  74 {
  75         struct rose_sock *rose = rose_sk(sk);
  76
  77         del_timer(&rose->timer);
  78
  79         rose->timer.data     = (unsigned long)sk;
  80         rose->timer.function = &rose_timer_expiry;
  81         rose->timer.expires  = jiffies + rose->t3;
  82
  83         add_timer(&rose->timer);
  84 }
  85
  86 void rose_start_hbtimer(struct sock *sk)
  87 {
  88         struct rose_sock *rose = rose_sk(sk);
  89
  90         del_timer(&rose->timer);
  91
  92         rose->timer.data     = (unsigned long)sk;
  93         rose->timer.function = &rose_timer_expiry;
  94         rose->timer.expires  = jiffies + rose->hb;
  95
  96         add_timer(&rose->timer);
  97 }
  98
  99 void rose_start_idletimer(struct sock *sk)
 100 {
 101         struct rose_sock *rose = rose_sk(sk);
 102
 103         del_timer(&rose->idletimer);
 104
 105         if (rose->idle > 0) {
 106                 rose->idletimer.data     = (unsigned long)sk;
 107                 rose->idletimer.function = &rose_idletimer_expiry;
 108                 rose->idletimer.expires  = jiffies + rose->idle;
 109
 110                 add_timer(&rose->idletimer);
 111         }
 112 }
 113
 114 void rose_stop_heartbeat(struct sock *sk)
 115 {
 116         del_timer(&sk->sk_timer);
 117 }
 118
 119 void rose_stop_timer(struct sock *sk)
 120 {
 121         del_timer(&rose_sk(sk)->timer);
 122 }
 123
 124 void rose_stop_idletimer(struct sock *sk)
 125 {
 126         del_timer(&rose_sk(sk)->idletimer);
 127 }
 128
 129 static void rose_heartbeat_expiry(unsigned long param)
 130 {
 131         struct sock *sk = (struct sock *)param;
 132         struct rose_sock *rose = rose_sk(sk);
 133
 134         bh_lock_sock(sk);
 135         switch (rose->state) {
 136         case ROSE_STATE_0:
 137                 /* Magic here: If we listen() and a new link dies before it
 138                    is accepted() it isn't 'dead' so doesn't get removed. */
 139                 if (sock_flag(sk, SOCK_DESTROY) ||
 140                     (sk->sk_state == TCP_LISTEN && sock_flag(sk, SOCK_DEAD))) {
 141                         rose_destroy_socket(sk);
 142                         return;
 143                 }
 144                 break;
 145
 146         case ROSE_STATE_3:
 147                 /*
 148                  * Check for the state of the receive buffer.
 149                  */
 150                 if (atomic_read(&sk->sk_rmem_alloc) < (sk->sk_rcvbuf / 2) &&
 151                     (rose->condition & ROSE_COND_OWN_RX_BUSY)) {
 152                         rose->condition &= ~ROSE_COND_OWN_RX_BUSY;
 153                         rose->condition &= ~ROSE_COND_ACK_PENDING;
 154                         rose->vl         = rose->vr;
 155                         rose_write_internal(sk, ROSE_RR);
 156                         rose_stop_timer(sk);    /* HB */
 157                         break;
 158                 }
 159                 break;
 160         }
 161
 162         rose_start_heartbeat(sk);
 163         bh_unlock_sock(sk);
 164 }
 165
 166 static void rose_timer_expiry(unsigned long param)
 167 {
 168         struct sock *sk = (struct sock *)param;
 169         struct rose_sock *rose = rose_sk(sk);
 170
 171         bh_lock_sock(sk);
 172         switch (rose->state) {
 173         case ROSE_STATE_1:      /* T1 */
 174         case ROSE_STATE_4:      /* T2 */
 175                 rose_write_internal(sk, ROSE_CLEAR_REQUEST);
 176                 rose->state = ROSE_STATE_2;
 177                 rose_start_t3timer(sk);
 178                 break;
 179
 180         case ROSE_STATE_2:      /* T3 */
 181                 rose->neighbour->use--;
 182                 rose_disconnect(sk, ETIMEDOUT, -1, -1);
 183                 break;
 184
 185         case ROSE_STATE_3:      /* HB */
 186                 if (rose->condition & ROSE_COND_ACK_PENDING) {
 187                         rose->condition &= ~ROSE_COND_ACK_PENDING;
 188                         rose_enquiry_response(sk);
 189                 }
 190                 break;
 191         }
 192         bh_unlock_sock(sk);
 193 }
 194
 195 static void rose_idletimer_expiry(unsigned long param)
 196 {
 197         struct sock *sk = (struct sock *)param;
 198
 199         bh_lock_sock(sk);
 200         rose_clear_queues(sk);
 201
 202         rose_write_internal(sk, ROSE_CLEAR_REQUEST);
 203         rose_sk(sk)->state = ROSE_STATE_2;
 204
 205         rose_start_t3timer(sk);
 206
 207         sk->sk_state     = TCP_CLOSE;
 208         sk->sk_err       = 0;
 209         sk->sk_shutdown |= SEND_SHUTDOWN;
 210
 211         if (!sock_flag(sk, SOCK_DEAD)) {
 212                 sk->sk_state_change(sk);
 213                 sock_set_flag(sk, SOCK_DEAD);
 214         }
 215         bh_unlock_sock(sk);
 216 }