diff options
Diffstat (limited to 'net/bridge/br_stp_timer.c')
| -rw-r--r-- | net/bridge/br_stp_timer.c | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/net/bridge/br_stp_timer.c b/net/bridge/br_stp_timer.c new file mode 100644 index 000000000..27bf1979b --- /dev/null +++ b/net/bridge/br_stp_timer.c @@ -0,0 +1,161 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Spanning tree protocol; timer-related code + * Linux ethernet bridge + * + * Authors: + * Lennert Buytenhek <buytenh@gnu.org> + */ + +#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(struct timer_list *t) +{ + struct net_bridge *br = from_timer(br, t, hello_timer); + + br_debug(br, "hello timer expired\n"); + spin_lock(&br->lock); + if (br->dev->flags & IFF_UP) { + br_config_bpdu_generation(br); + + if (br->stp_enabled == BR_KERNEL_STP) + mod_timer(&br->hello_timer, + round_jiffies(jiffies + br->hello_time)); + } + spin_unlock(&br->lock); +} + +static void br_message_age_timer_expired(struct timer_list *t) +{ + struct net_bridge_port *p = from_timer(p, t, message_age_timer); + 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 int) 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(struct timer_list *t) +{ + struct net_bridge_port *p = from_timer(p, t, forward_delay_timer); + struct net_bridge *br = p->br; + + br_debug(br, "port %u(%s) forward delay timer\n", + (unsigned int) p->port_no, p->dev->name); + spin_lock(&br->lock); + if (p->state == BR_STATE_LISTENING) { + br_set_state(p, BR_STATE_LEARNING); + mod_timer(&p->forward_delay_timer, + jiffies + br->forward_delay); + } else if (p->state == BR_STATE_LEARNING) { + br_set_state(p, BR_STATE_FORWARDING); + if (br_is_designated_for_some_port(br)) + br_topology_change_detection(br); + netif_carrier_on(br->dev); + } + rcu_read_lock(); + br_ifinfo_notify(RTM_NEWLINK, NULL, p); + rcu_read_unlock(); + spin_unlock(&br->lock); +} + +static void br_tcn_timer_expired(struct timer_list *t) +{ + struct net_bridge *br = from_timer(br, t, tcn_timer); + + br_debug(br, "tcn timer expired\n"); + spin_lock(&br->lock); + if (!br_is_root_bridge(br) && (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(struct timer_list *t) +{ + struct net_bridge *br = from_timer(br, t, topology_change_timer); + + br_debug(br, "topo change timer expired\n"); + spin_lock(&br->lock); + br->topology_change_detected = 0; + __br_set_topology_change(br, 0); + spin_unlock(&br->lock); +} + +static void br_hold_timer_expired(struct timer_list *t) +{ + struct net_bridge_port *p = from_timer(p, t, hold_timer); + + br_debug(p->br, "port %u(%s) hold timer expired\n", + (unsigned int) 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) +{ + timer_setup(&br->hello_timer, br_hello_timer_expired, 0); + timer_setup(&br->tcn_timer, br_tcn_timer_expired, 0); + timer_setup(&br->topology_change_timer, + br_topology_change_timer_expired, 0); +} + +void br_stp_port_timer_init(struct net_bridge_port *p) +{ + timer_setup(&p->message_age_timer, br_message_age_timer_expired, 0); + timer_setup(&p->forward_delay_timer, br_forward_delay_timer_expired, 0); + timer_setup(&p->hold_timer, br_hold_timer_expired, 0); +} + +/* Report ticks left (in USER_HZ) used for API */ +unsigned long br_timer_value(const struct timer_list *timer) +{ + return timer_pending(timer) + ? jiffies_delta_to_clock_t(timer->expires - jiffies) : 0; +} |