linux/net/bridge/br_stp_timer.c
stephen hemminger 1faa4356a3 bridge: control carrier based on ports online
This makes the bridge device behave like a physical device.
In earlier releases the bridge always asserted carrier. This
changes the behavior so that bridge device carrier is on only
if one or more ports are in the forwarding state. This
should help IPv6 autoconfiguration, DHCP, and routing daemons.

I did brief testing with Network and Virt manager and they
seem fine, but since this changes behavior of bridge, it should
wait until net-next (2.6.39).

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Reviewed-by: Nicolas de Pesloüan <nicolas.2p.debian@free.fr>
Tested-By: Adam Majer <adamm@zombino.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-03-14 14:29:02 -07:00

174 lines
4.4 KiB
C

/*
* Spanning tree protocol; timer-related code
* Linux ethernet bridge
*
* Authors:
* Lennert Buytenhek <buytenh@gnu.org>
*
* 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/times.h>
#include "br_private.h"
#include "br_private_stp.h"
/* called under bridge lock */
static int br_is_designated_for_some_port(const struct net_bridge *br)
{
struct net_bridge_port *p;
list_for_each_entry(p, &br->port_list, list) {
if (p->state != BR_STATE_DISABLED &&
!memcmp(&p->designated_bridge, &br->bridge_id, 8))
return 1;
}
return 0;
}
static void br_hello_timer_expired(unsigned long arg)
{
struct net_bridge *br = (struct net_bridge *)arg;
br_debug(br, "hello timer expired\n");
spin_lock(&br->lock);
if (br->dev->flags & IFF_UP) {
br_config_bpdu_generation(br);
mod_timer(&br->hello_timer, round_jiffies(jiffies + br->hello_time));
}
spin_unlock(&br->lock);
}
static void br_message_age_timer_expired(unsigned long arg)
{
struct net_bridge_port *p = (struct net_bridge_port *) arg;
struct net_bridge *br = p->br;
const bridge_id *id = &p->designated_bridge;
int was_root;
if (p->state == BR_STATE_DISABLED)
return;
br_info(br, "port %u(%s) neighbor %.2x%.2x.%pM lost\n",
(unsigned) p->port_no, p->dev->name,
id->prio[0], id->prio[1], &id->addr);
/*
* 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.
*/
spin_lock(&br->lock);
if (p->state == BR_STATE_DISABLED)
goto unlock;
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);
unlock:
spin_unlock(&br->lock);
}
static void br_forward_delay_timer_expired(unsigned long arg)
{
struct net_bridge_port *p = (struct net_bridge_port *) arg;
struct net_bridge *br = p->br;
br_debug(br, "port %u(%s) forward delay timer\n",
(unsigned) p->port_no, p->dev->name);
spin_lock(&br->lock);
if (p->state == BR_STATE_LISTENING) {
p->state = BR_STATE_LEARNING;
mod_timer(&p->forward_delay_timer,
jiffies + br->forward_delay);
} else if (p->state == BR_STATE_LEARNING) {
p->state = BR_STATE_FORWARDING;
if (br_is_designated_for_some_port(br))
br_topology_change_detection(br);
netif_carrier_on(br->dev);
}
br_log_state(p);
spin_unlock(&br->lock);
}
static void br_tcn_timer_expired(unsigned long arg)
{
struct net_bridge *br = (struct net_bridge *) arg;
br_debug(br, "tcn timer expired\n");
spin_lock(&br->lock);
if (br->dev->flags & IFF_UP) {
br_transmit_tcn(br);
mod_timer(&br->tcn_timer,jiffies + br->bridge_hello_time);
}
spin_unlock(&br->lock);
}
static void br_topology_change_timer_expired(unsigned long arg)
{
struct net_bridge *br = (struct net_bridge *) arg;
br_debug(br, "topo change timer expired\n");
spin_lock(&br->lock);
br->topology_change_detected = 0;
br->topology_change = 0;
spin_unlock(&br->lock);
}
static void br_hold_timer_expired(unsigned long arg)
{
struct net_bridge_port *p = (struct net_bridge_port *) arg;
br_debug(p->br, "port %u(%s) hold timer expired\n",
(unsigned) p->port_no, p->dev->name);
spin_lock(&p->br->lock);
if (p->config_pending)
br_transmit_config(p);
spin_unlock(&p->br->lock);
}
void br_stp_timer_init(struct net_bridge *br)
{
setup_timer(&br->hello_timer, br_hello_timer_expired,
(unsigned long) br);
setup_timer(&br->tcn_timer, br_tcn_timer_expired,
(unsigned long) br);
setup_timer(&br->topology_change_timer,
br_topology_change_timer_expired,
(unsigned long) br);
setup_timer(&br->gc_timer, br_fdb_cleanup, (unsigned long) br);
}
void br_stp_port_timer_init(struct net_bridge_port *p)
{
setup_timer(&p->message_age_timer, br_message_age_timer_expired,
(unsigned long) p);
setup_timer(&p->forward_delay_timer, br_forward_delay_timer_expired,
(unsigned long) p);
setup_timer(&p->hold_timer, br_hold_timer_expired,
(unsigned long) p);
}
/* Report ticks left (in USER_HZ) used for API */
unsigned long br_timer_value(const struct timer_list *timer)
{
return timer_pending(timer)
? jiffies_to_clock_t(timer->expires - jiffies) : 0;
}