1 /* 2 * LAPB release 002 3 * 4 * This code REQUIRES 2.1.15 or higher/ NET3.038 5 * 6 * This module: 7 * This module is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License 9 * as published by the Free Software Foundation; either version 10 * 2 of the License, or (at your option) any later version. 11 * 12 * History 13 * LAPB 001 Jonathan Naylor Started Coding 14 * LAPB 002 Jonathan Naylor New timer architecture. 15 */ 16 17 #include <linux/errno.h> 18 #include <linux/types.h> 19 #include <linux/socket.h> 20 #include <linux/in.h> 21 #include <linux/kernel.h> 22 #include <linux/jiffies.h> 23 #include <linux/timer.h> 24 #include <linux/string.h> 25 #include <linux/sockios.h> 26 #include <linux/net.h> 27 #include <linux/inet.h> 28 #include <linux/skbuff.h> 29 #include <net/sock.h> 30 #include <asm/uaccess.h> 31 #include <asm/system.h> 32 #include <linux/fcntl.h> 33 #include <linux/mm.h> 34 #include <linux/interrupt.h> 35 #include <net/lapb.h> 36 37 static void lapb_t1timer_expiry(unsigned long); 38 static void lapb_t2timer_expiry(unsigned long); 39 40 void lapb_start_t1timer(struct lapb_cb *lapb) 41 { 42 del_timer(&lapb->t1timer); 43 44 lapb->t1timer.data = (unsigned long)lapb; 45 lapb->t1timer.function = &lapb_t1timer_expiry; 46 lapb->t1timer.expires = jiffies + lapb->t1; 47 48 add_timer(&lapb->t1timer); 49 } 50 51 void lapb_start_t2timer(struct lapb_cb *lapb) 52 { 53 del_timer(&lapb->t2timer); 54 55 lapb->t2timer.data = (unsigned long)lapb; 56 lapb->t2timer.function = &lapb_t2timer_expiry; 57 lapb->t2timer.expires = jiffies + lapb->t2; 58 59 add_timer(&lapb->t2timer); 60 } 61 62 void lapb_stop_t1timer(struct lapb_cb *lapb) 63 { 64 del_timer(&lapb->t1timer); 65 } 66 67 void lapb_stop_t2timer(struct lapb_cb *lapb) 68 { 69 del_timer(&lapb->t2timer); 70 } 71 72 int lapb_t1timer_running(struct lapb_cb *lapb) 73 { 74 return timer_pending(&lapb->t1timer); 75 } 76 77 static void lapb_t2timer_expiry(unsigned long param) 78 { 79 struct lapb_cb *lapb = (struct lapb_cb *)param; 80 81 if (lapb->condition & LAPB_ACK_PENDING_CONDITION) { 82 lapb->condition &= ~LAPB_ACK_PENDING_CONDITION; 83 lapb_timeout_response(lapb); 84 } 85 } 86 87 static void lapb_t1timer_expiry(unsigned long param) 88 { 89 struct lapb_cb *lapb = (struct lapb_cb *)param; 90 91 switch (lapb->state) { 92 93 /* 94 * If we are a DCE, keep going DM .. DM .. DM 95 */ 96 case LAPB_STATE_0: 97 if (lapb->mode & LAPB_DCE) 98 lapb_send_control(lapb, LAPB_DM, LAPB_POLLOFF, LAPB_RESPONSE); 99 break; 100 101 /* 102 * Awaiting connection state, send SABM(E), up to N2 times. 103 */ 104 case LAPB_STATE_1: 105 if (lapb->n2count == lapb->n2) { 106 lapb_clear_queues(lapb); 107 lapb->state = LAPB_STATE_0; 108 lapb_disconnect_indication(lapb, LAPB_TIMEDOUT); 109 #if LAPB_DEBUG > 0 110 printk(KERN_DEBUG "lapb: (%p) S1 -> S0\n", lapb->dev); 111 #endif 112 return; 113 } else { 114 lapb->n2count++; 115 if (lapb->mode & LAPB_EXTENDED) { 116 #if LAPB_DEBUG > 1 117 printk(KERN_DEBUG "lapb: (%p) S1 TX SABME(1)\n", lapb->dev); 118 #endif 119 lapb_send_control(lapb, LAPB_SABME, LAPB_POLLON, LAPB_COMMAND); 120 } else { 121 #if LAPB_DEBUG > 1 122 printk(KERN_DEBUG "lapb: (%p) S1 TX SABM(1)\n", lapb->dev); 123 #endif 124 lapb_send_control(lapb, LAPB_SABM, LAPB_POLLON, LAPB_COMMAND); 125 } 126 } 127 break; 128 129 /* 130 * Awaiting disconnection state, send DISC, up to N2 times. 131 */ 132 case LAPB_STATE_2: 133 if (lapb->n2count == lapb->n2) { 134 lapb_clear_queues(lapb); 135 lapb->state = LAPB_STATE_0; 136 lapb_disconnect_confirmation(lapb, LAPB_TIMEDOUT); 137 #if LAPB_DEBUG > 0 138 printk(KERN_DEBUG "lapb: (%p) S2 -> S0\n", lapb->dev); 139 #endif 140 return; 141 } else { 142 lapb->n2count++; 143 #if LAPB_DEBUG > 1 144 printk(KERN_DEBUG "lapb: (%p) S2 TX DISC(1)\n", lapb->dev); 145 #endif 146 lapb_send_control(lapb, LAPB_DISC, LAPB_POLLON, LAPB_COMMAND); 147 } 148 break; 149 150 /* 151 * Data transfer state, restransmit I frames, up to N2 times. 152 */ 153 case LAPB_STATE_3: 154 if (lapb->n2count == lapb->n2) { 155 lapb_clear_queues(lapb); 156 lapb->state = LAPB_STATE_0; 157 lapb_stop_t2timer(lapb); 158 lapb_disconnect_indication(lapb, LAPB_TIMEDOUT); 159 #if LAPB_DEBUG > 0 160 printk(KERN_DEBUG "lapb: (%p) S3 -> S0\n", lapb->dev); 161 #endif 162 return; 163 } else { 164 lapb->n2count++; 165 lapb_requeue_frames(lapb); 166 } 167 break; 168 169 /* 170 * Frame reject state, restransmit FRMR frames, up to N2 times. 171 */ 172 case LAPB_STATE_4: 173 if (lapb->n2count == lapb->n2) { 174 lapb_clear_queues(lapb); 175 lapb->state = LAPB_STATE_0; 176 lapb_disconnect_indication(lapb, LAPB_TIMEDOUT); 177 #if LAPB_DEBUG > 0 178 printk(KERN_DEBUG "lapb: (%p) S4 -> S0\n", lapb->dev); 179 #endif 180 return; 181 } else { 182 lapb->n2count++; 183 lapb_transmit_frmr(lapb); 184 } 185 break; 186 } 187 188 lapb_start_t1timer(lapb); 189 } 190