1 /* 2 * Spanning tree protocol; timer-related code 3 * Linux ethernet bridge 4 * 5 * Authors: 6 * Lennert Buytenhek <buytenh@gnu.org> 7 * 8 * $Id: br_stp_timer.c,v 1.3 2000/05/05 02:17:17 davem Exp $ 9 * 10 * This program is free software; you can redistribute it and/or 11 * modify it under the terms of the GNU General Public License 12 * as published by the Free Software Foundation; either version 13 * 2 of the License, or (at your option) any later version. 14 */ 15 16 #include <linux/kernel.h> 17 #include <linux/times.h> 18 #include <linux/smp_lock.h> 19 20 #include "br_private.h" 21 #include "br_private_stp.h" 22 23 /* called under bridge lock */ 24 static int br_is_designated_for_some_port(const struct net_bridge *br) 25 { 26 struct net_bridge_port *p; 27 28 list_for_each_entry(p, &br->port_list, list) { 29 if (p->state != BR_STATE_DISABLED && 30 !memcmp(&p->designated_bridge, &br->bridge_id, 8)) 31 return 1; 32 } 33 34 return 0; 35 } 36 37 static void br_hello_timer_expired(unsigned long arg) 38 { 39 struct net_bridge *br = (struct net_bridge *)arg; 40 41 pr_debug("%s: hello timer expired\n", br->dev->name); 42 spin_lock_bh(&br->lock); 43 if (br->dev->flags & IFF_UP) { 44 br_config_bpdu_generation(br); 45 46 mod_timer(&br->hello_timer, jiffies + br->hello_time); 47 } 48 spin_unlock_bh(&br->lock); 49 } 50 51 static void br_message_age_timer_expired(unsigned long arg) 52 { 53 struct net_bridge_port *p = (struct net_bridge_port *) arg; 54 struct net_bridge *br = p->br; 55 const bridge_id *id = &p->designated_bridge; 56 int was_root; 57 58 if (p->state == BR_STATE_DISABLED) 59 return; 60 61 62 pr_info("%s: neighbor %.2x%.2x.%.2x:%.2x:%.2x:%.2x:%.2x:%.2x lost on port %d(%s)\n", 63 br->dev->name, 64 id->prio[0], id->prio[1], 65 id->addr[0], id->addr[1], id->addr[2], 66 id->addr[3], id->addr[4], id->addr[5], 67 p->port_no, p->dev->name); 68 69 /* 70 * According to the spec, the message age timer cannot be 71 * running when we are the root bridge. So.. this was_root 72 * check is redundant. I'm leaving it in for now, though. 73 */ 74 spin_lock_bh(&br->lock); 75 if (p->state == BR_STATE_DISABLED) 76 goto unlock; 77 was_root = br_is_root_bridge(br); 78 79 br_become_designated_port(p); 80 br_configuration_update(br); 81 br_port_state_selection(br); 82 if (br_is_root_bridge(br) && !was_root) 83 br_become_root_bridge(br); 84 unlock: 85 spin_unlock_bh(&br->lock); 86 } 87 88 static void br_forward_delay_timer_expired(unsigned long arg) 89 { 90 struct net_bridge_port *p = (struct net_bridge_port *) arg; 91 struct net_bridge *br = p->br; 92 93 pr_debug("%s: %d(%s) forward delay timer\n", 94 br->dev->name, p->port_no, p->dev->name); 95 spin_lock_bh(&br->lock); 96 if (p->state == BR_STATE_LISTENING) { 97 p->state = BR_STATE_LEARNING; 98 mod_timer(&p->forward_delay_timer, 99 jiffies + br->forward_delay); 100 } else if (p->state == BR_STATE_LEARNING) { 101 p->state = BR_STATE_FORWARDING; 102 if (br_is_designated_for_some_port(br)) 103 br_topology_change_detection(br); 104 } 105 br_log_state(p); 106 spin_unlock_bh(&br->lock); 107 } 108 109 static void br_tcn_timer_expired(unsigned long arg) 110 { 111 struct net_bridge *br = (struct net_bridge *) arg; 112 113 pr_debug("%s: tcn timer expired\n", br->dev->name); 114 spin_lock_bh(&br->lock); 115 if (br->dev->flags & IFF_UP) { 116 br_transmit_tcn(br); 117 118 mod_timer(&br->tcn_timer,jiffies + br->bridge_hello_time); 119 } 120 spin_unlock_bh(&br->lock); 121 } 122 123 static void br_topology_change_timer_expired(unsigned long arg) 124 { 125 struct net_bridge *br = (struct net_bridge *) arg; 126 127 pr_debug("%s: topo change timer expired\n", br->dev->name); 128 spin_lock_bh(&br->lock); 129 br->topology_change_detected = 0; 130 br->topology_change = 0; 131 spin_unlock_bh(&br->lock); 132 } 133 134 static void br_hold_timer_expired(unsigned long arg) 135 { 136 struct net_bridge_port *p = (struct net_bridge_port *) arg; 137 138 pr_debug("%s: %d(%s) hold timer expired\n", 139 p->br->dev->name, p->port_no, p->dev->name); 140 141 spin_lock_bh(&p->br->lock); 142 if (p->config_pending) 143 br_transmit_config(p); 144 spin_unlock_bh(&p->br->lock); 145 } 146 147 static inline void br_timer_init(struct timer_list *timer, 148 void (*_function)(unsigned long), 149 unsigned long _data) 150 { 151 init_timer(timer); 152 timer->function = _function; 153 timer->data = _data; 154 } 155 156 void br_stp_timer_init(struct net_bridge *br) 157 { 158 br_timer_init(&br->hello_timer, br_hello_timer_expired, 159 (unsigned long) br); 160 161 br_timer_init(&br->tcn_timer, br_tcn_timer_expired, 162 (unsigned long) br); 163 164 br_timer_init(&br->topology_change_timer, 165 br_topology_change_timer_expired, 166 (unsigned long) br); 167 168 br_timer_init(&br->gc_timer, br_fdb_cleanup, (unsigned long) br); 169 } 170 171 void br_stp_port_timer_init(struct net_bridge_port *p) 172 { 173 br_timer_init(&p->message_age_timer, br_message_age_timer_expired, 174 (unsigned long) p); 175 176 br_timer_init(&p->forward_delay_timer, br_forward_delay_timer_expired, 177 (unsigned long) p); 178 179 br_timer_init(&p->hold_timer, br_hold_timer_expired, 180 (unsigned long) p); 181 } 182 183 /* Report ticks left (in USER_HZ) used for API */ 184 unsigned long br_timer_value(const struct timer_list *timer) 185 { 186 return timer_pending(timer) 187 ? jiffies_to_clock_t(timer->expires - jiffies) : 0; 188 } 189