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