Viewing file:  ax25_ds_timer.c (5.67 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
/*
* AX.25 release 037
*
* This code REQUIRES 2.1.15 or higher/ NET3.038
*
* This module:
* This module is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
* History
* AX.25 036 Jonathan(G4KLX) Cloned from ax25_timer.c.
* Joerg(DL1BKE) Added DAMA Slave Timeout timer
* AX.25 037 Jonathan(G4KLX) New timer architecture.
*/
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/timer.h>
#include <linux/string.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <net/ax25.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <linux/fcntl.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
static void ax25_ds_timeout(unsigned long);
/*
* Add DAMA slave timeout timer to timer list.
* Unlike the connection based timers the timeout function gets
* triggered every second. Please note that NET_AX25_DAMA_SLAVE_TIMEOUT
* (aka /proc/sys/net/ax25/{dev}/dama_slave_timeout) is still in
* 1/10th of a second.
*/
static void ax25_ds_add_timer(ax25_dev *ax25_dev)
{
struct timer_list *t = &ax25_dev->dama.slave_timer;
t->data = (unsigned long) ax25_dev;
t->function = &ax25_ds_timeout;
t->expires = jiffies + HZ;
add_timer(t);
}
void ax25_ds_del_timer(ax25_dev *ax25_dev)
{
if (ax25_dev) del_timer(&ax25_dev->dama.slave_timer);
}
void ax25_ds_set_timer(ax25_dev *ax25_dev)
{
if (ax25_dev == NULL) /* paranoia */
return;
del_timer(&ax25_dev->dama.slave_timer);
ax25_dev->dama.slave_timeout = ax25_dev->values[AX25_VALUES_DS_TIMEOUT] / 10;
ax25_ds_add_timer(ax25_dev);
}
/*
* DAMA Slave Timeout
* Silently discard all (slave) connections in case our master forgot us...
*/
static void ax25_ds_timeout(unsigned long arg)
{
ax25_dev *ax25_dev = (struct ax25_dev *) arg;
ax25_cb *ax25;
if (ax25_dev == NULL || !ax25_dev->dama.slave)
return; /* Yikes! */
if (!ax25_dev->dama.slave_timeout || --ax25_dev->dama.slave_timeout) {
ax25_ds_set_timer(ax25_dev);
return;
}
for (ax25=ax25_list; ax25 != NULL; ax25 = ax25->next) {
if (ax25->ax25_dev != ax25_dev || !(ax25->condition & AX25_COND_DAMA_MODE))
continue;
ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
ax25_disconnect(ax25, ETIMEDOUT);
}
ax25_dev_dama_off(ax25_dev);
}
void ax25_ds_heartbeat_expiry(ax25_cb *ax25)
{
switch (ax25->state) {
case AX25_STATE_0:
/* Magic here: If we listen() and a new link dies before it
is accepted() it isn't 'dead' so doesn't get removed. */
if (ax25->sk == NULL || ax25->sk->destroy || (ax25->sk->state == TCP_LISTEN && ax25->sk->dead)) {
ax25_destroy_socket(ax25);
return;
}
break;
case AX25_STATE_3:
/*
* Check the state of the receive buffer.
*/
if (ax25->sk != NULL) {
if (atomic_read(&ax25->sk->rmem_alloc) < (ax25->sk->rcvbuf / 2) &&
(ax25->condition & AX25_COND_OWN_RX_BUSY)) {
ax25->condition &= ~AX25_COND_OWN_RX_BUSY;
ax25->condition &= ~AX25_COND_ACK_PENDING;
break;
}
}
break;
}
ax25_start_heartbeat(ax25);
}
/* dl1bke 960114: T3 works much like the IDLE timeout, but
* gets reloaded with every frame for this
* connection.
*/
void ax25_ds_t3timer_expiry(ax25_cb *ax25)
{
ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
ax25_dama_off(ax25);
ax25_disconnect(ax25, ETIMEDOUT);
}
/* dl1bke 960228: close the connection when IDLE expires.
* unlike T3 this timer gets reloaded only on
* I frames.
*/
void ax25_ds_idletimer_expiry(ax25_cb *ax25)
{
ax25_clear_queues(ax25);
ax25->n2count = 0;
ax25->state = AX25_STATE_2;
ax25_calculate_t1(ax25);
ax25_start_t1timer(ax25);
ax25_stop_t3timer(ax25);
if (ax25->sk != NULL) {
ax25->sk->state = TCP_CLOSE;
ax25->sk->err = 0;
ax25->sk->shutdown |= SEND_SHUTDOWN;
if (!ax25->sk->dead)
ax25->sk->state_change(ax25->sk);
ax25->sk->dead = 1;
}
}
/* dl1bke 960114: The DAMA protocol requires to send data and SABM/DISC
* within the poll of any connected channel. Remember
* that we are not allowed to send anything unless we
* get polled by the Master.
*
* Thus we'll have to do parts of our T1 handling in
* ax25_enquiry_response().
*/
void ax25_ds_t1_timeout(ax25_cb *ax25)
{
switch (ax25->state) {
case AX25_STATE_1:
if (ax25->n2count == ax25->n2) {
if (ax25->modulus == AX25_MODULUS) {
ax25_disconnect(ax25, ETIMEDOUT);
return;
} else {
ax25->modulus = AX25_MODULUS;
ax25->window = ax25->ax25_dev->values[AX25_VALUES_WINDOW];
ax25->n2count = 0;
ax25_send_control(ax25, AX25_SABM, AX25_POLLOFF, AX25_COMMAND);
}
} else {
ax25->n2count++;
if (ax25->modulus == AX25_MODULUS)
ax25_send_control(ax25, AX25_SABM, AX25_POLLOFF, AX25_COMMAND);
else
ax25_send_control(ax25, AX25_SABME, AX25_POLLOFF, AX25_COMMAND);
}
break;
case AX25_STATE_2:
if (ax25->n2count == ax25->n2) {
ax25_send_control(ax25, AX25_DISC, AX25_POLLON, AX25_COMMAND);
ax25_disconnect(ax25, ETIMEDOUT);
return;
} else {
ax25->n2count++;
}
break;
case AX25_STATE_3:
if (ax25->n2count == ax25->n2) {
ax25_send_control(ax25, AX25_DM, AX25_POLLON, AX25_RESPONSE);
ax25_disconnect(ax25, ETIMEDOUT);
return;
} else {
ax25->n2count++;
}
break;
}
ax25_calculate_t1(ax25);
ax25_start_t1timer(ax25);
}
|