// 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 = timer_container_of(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 = timer_container_of(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 = timer_container_of(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 = timer_container_of(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 = timer_container_of(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 = timer_container_of(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(READ_ONCE(timer->expires) - jiffies) : 0;}