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/*
* Spanning tree protocol; timer-related code
* Linux ethernet bridge
*
* Authors:
* Lennert Buytenhek <buytenh@gnu.org>
*
* $Id: br_stp_timer.c,v 1.3 2000/05/05 02:17:17 davem Exp $
*
* This program 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.
*/
#include <linux/kernel.h>
#include <linux/if_bridge.h>
#include <linux/smp_lock.h>
#include <asm/uaccess.h>
#include "br_private.h"
#include "br_private_stp.h"
static void dump_bridge_id(bridge_id *id)
{
printk("%.2x%.2x.%.2x:%.2x:%.2x:%.2x:%.2x:%.2x", id->prio[0],
id->prio[1], id->addr[0], id->addr[1], id->addr[2], id->addr[3],
id->addr[4], id->addr[5]);
}
/* called under bridge lock */
static int br_is_designated_for_some_port(struct net_bridge *br)
{
struct net_bridge_port *p;
p = br->port_list;
while (p != NULL) {
if (p->state != BR_STATE_DISABLED &&
!memcmp(&p->designated_bridge, &br->bridge_id, 8))
return 1;
p = p->next;
}
return 0;
}
/* called under bridge lock */
static void br_hello_timer_expired(struct net_bridge *br)
{
br_config_bpdu_generation(br);
br_timer_set(&br->hello_timer, jiffies);
}
/* called under bridge lock */
static void br_message_age_timer_expired(struct net_bridge_port *p)
{
struct net_bridge *br;
int was_root;
br = p->br;
printk(KERN_INFO "%s: ", br->dev.name);
printk("neighbour ");
dump_bridge_id(&p->designated_bridge);
printk(" lost on port %i(%s)\n", p->port_no, p->dev->name);
/*
* According to the spec, the message age timer cannot be
* running when we are the root bridge. So.. this was_root
* check is redundant. I'm leaving it in for now, though.
*/
was_root = br_is_root_bridge(br);
br_become_designated_port(p);
br_configuration_update(br);
br_port_state_selection(br);
if (br_is_root_bridge(br) && !was_root)
br_become_root_bridge(br);
}
/* called under bridge lock */
static void br_forward_delay_timer_expired(struct net_bridge_port *p)
{
if (p->state == BR_STATE_LISTENING) {
printk(KERN_INFO "%s: port %i(%s) entering %s state\n",
p->br->dev.name, p->port_no, p->dev->name, "learning");
p->state = BR_STATE_LEARNING;
br_timer_set(&p->forward_delay_timer, jiffies);
} else if (p->state == BR_STATE_LEARNING) {
printk(KERN_INFO "%s: port %i(%s) entering %s state\n",
p->br->dev.name, p->port_no, p->dev->name, "forwarding");
p->state = BR_STATE_FORWARDING;
if (br_is_designated_for_some_port(p->br))
br_topology_change_detection(p->br);
}
}
/* called under bridge lock */
static void br_tcn_timer_expired(struct net_bridge *br)
{
printk(KERN_INFO "%s: retransmitting tcn bpdu\n", br->dev.name);
br_transmit_tcn(br);
br_timer_set(&br->tcn_timer, jiffies);
}
/* called under bridge lock */
static void br_topology_change_timer_expired(struct net_bridge *br)
{
br->topology_change_detected = 0;
br->topology_change = 0;
}
/* called under bridge lock */
static void br_hold_timer_expired(struct net_bridge_port *p)
{
if (p->config_pending)
br_transmit_config(p);
}
/* called under bridge lock */
static void br_check_port_timers(struct net_bridge_port *p)
{
if (br_timer_has_expired(&p->message_age_timer, p->br->max_age)) {
br_timer_clear(&p->message_age_timer);
br_message_age_timer_expired(p);
}
if (br_timer_has_expired(&p->forward_delay_timer, p->br->forward_delay)) {
br_timer_clear(&p->forward_delay_timer);
br_forward_delay_timer_expired(p);
}
if (br_timer_has_expired(&p->hold_timer, BR_HOLD_TIME)) {
br_timer_clear(&p->hold_timer);
br_hold_timer_expired(p);
}
}
/* called under bridge lock */
static void br_check_timers(struct net_bridge *br)
{
struct net_bridge_port *p;
if (br_timer_has_expired(&br->gc_timer, br->gc_interval)) {
br_timer_set(&br->gc_timer, jiffies);
br_fdb_cleanup(br);
}
if (br_timer_has_expired(&br->hello_timer, br->hello_time)) {
br_timer_clear(&br->hello_timer);
br_hello_timer_expired(br);
}
if (br_timer_has_expired(&br->tcn_timer, br->bridge_hello_time)) {
br_timer_clear(&br->tcn_timer);
br_tcn_timer_expired(br);
}
if (br_timer_has_expired(&br->topology_change_timer, br->bridge_forward_delay + br->bridge_max_age)) {
br_timer_clear(&br->topology_change_timer);
br_topology_change_timer_expired(br);
}
p = br->port_list;
while (p != NULL) {
if (p->state != BR_STATE_DISABLED)
br_check_port_timers(p);
p = p->next;
}
}
void br_tick(unsigned long __data)
{
struct net_bridge *br = (struct net_bridge *)__data;
read_lock(&br->lock);
br_check_timers(br);
read_unlock(&br->lock);
br->tick.expires = jiffies + 1;
add_timer(&br->tick);
}
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