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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 mod_timer(&br->hello_timer, round_jiffies(jiffies + br->hello_time));
44 }
45 spin_unlock(&br->lock);
46}
47
48static void br_message_age_timer_expired(unsigned long arg)
49{
50 struct net_bridge_port *p = (struct net_bridge_port *) arg;
51 struct net_bridge *br = p->br;
52 const bridge_id *id = &p->designated_bridge;
53 int was_root;
54
55 if (p->state == BR_STATE_DISABLED)
56 return;
57
58 br_info(br, "port %u(%s) neighbor %.2x%.2x.%pM lost\n",
59 (unsigned) p->port_no, p->dev->name,
60 id->prio[0], id->prio[1], &id->addr);
61
62 /*
63 * According to the spec, the message age timer cannot be
64 * running when we are the root bridge. So.. this was_root
65 * check is redundant. I'm leaving it in for now, though.
66 */
67 spin_lock(&br->lock);
68 if (p->state == BR_STATE_DISABLED)
69 goto unlock;
70 was_root = br_is_root_bridge(br);
71
72 br_become_designated_port(p);
73 br_configuration_update(br);
74 br_port_state_selection(br);
75 if (br_is_root_bridge(br) && !was_root)
76 br_become_root_bridge(br);
77 unlock:
78 spin_unlock(&br->lock);
79}
80
81static void br_forward_delay_timer_expired(unsigned long arg)
82{
83 struct net_bridge_port *p = (struct net_bridge_port *) arg;
84 struct net_bridge *br = p->br;
85
86 br_debug(br, "port %u(%s) forward delay timer\n",
87 (unsigned) p->port_no, p->dev->name);
88 spin_lock(&br->lock);
89 if (p->state == BR_STATE_LISTENING) {
90 p->state = BR_STATE_LEARNING;
91 mod_timer(&p->forward_delay_timer,
92 jiffies + br->forward_delay);
93 } else if (p->state == BR_STATE_LEARNING) {
94 p->state = BR_STATE_FORWARDING;
95 if (br_is_designated_for_some_port(br))
96 br_topology_change_detection(br);
97 netif_carrier_on(br->dev);
98 }
99 br_log_state(p);
100 br_ifinfo_notify(RTM_NEWLINK, p);
101 spin_unlock(&br->lock);
102}
103
104static void br_tcn_timer_expired(unsigned long arg)
105{
106 struct net_bridge *br = (struct net_bridge *) arg;
107
108 br_debug(br, "tcn timer expired\n");
109 spin_lock(&br->lock);
110 if (br->dev->flags & IFF_UP) {
111 br_transmit_tcn(br);
112
113 mod_timer(&br->tcn_timer,jiffies + br->bridge_hello_time);
114 }
115 spin_unlock(&br->lock);
116}
117
118static void br_topology_change_timer_expired(unsigned long arg)
119{
120 struct net_bridge *br = (struct net_bridge *) arg;
121
122 br_debug(br, "topo change timer expired\n");
123 spin_lock(&br->lock);
124 br->topology_change_detected = 0;
125 br->topology_change = 0;
126 spin_unlock(&br->lock);
127}
128
129static void br_hold_timer_expired(unsigned long arg)
130{
131 struct net_bridge_port *p = (struct net_bridge_port *) arg;
132
133 br_debug(p->br, "port %u(%s) hold timer expired\n",
134 (unsigned) p->port_no, p->dev->name);
135
136 spin_lock(&p->br->lock);
137 if (p->config_pending)
138 br_transmit_config(p);
139 spin_unlock(&p->br->lock);
140}
141
142void br_stp_timer_init(struct net_bridge *br)
143{
144 setup_timer(&br->hello_timer, br_hello_timer_expired,
145 (unsigned long) br);
146
147 setup_timer(&br->tcn_timer, br_tcn_timer_expired,
148 (unsigned long) br);
149
150 setup_timer(&br->topology_change_timer,
151 br_topology_change_timer_expired,
152 (unsigned long) br);
153
154 setup_timer(&br->gc_timer, br_fdb_cleanup, (unsigned long) br);
155}
156
157void br_stp_port_timer_init(struct net_bridge_port *p)
158{
159 setup_timer(&p->message_age_timer, br_message_age_timer_expired,
160 (unsigned long) p);
161
162 setup_timer(&p->forward_delay_timer, br_forward_delay_timer_expired,
163 (unsigned long) p);
164
165 setup_timer(&p->hold_timer, br_hold_timer_expired,
166 (unsigned long) p);
167}
168
169/* Report ticks left (in USER_HZ) used for API */
170unsigned long br_timer_value(const struct timer_list *timer)
171{
172 return timer_pending(timer)
173 ? jiffies_to_clock_t(timer->expires - jiffies) : 0;
174}
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Spanning tree protocol; timer-related code
4 * Linux ethernet bridge
5 *
6 * Authors:
7 * Lennert Buytenhek <buytenh@gnu.org>
8 */
9
10#include <linux/kernel.h>
11#include <linux/times.h>
12
13#include "br_private.h"
14#include "br_private_stp.h"
15
16/* called under bridge lock */
17static int br_is_designated_for_some_port(const struct net_bridge *br)
18{
19 struct net_bridge_port *p;
20
21 list_for_each_entry(p, &br->port_list, list) {
22 if (p->state != BR_STATE_DISABLED &&
23 !memcmp(&p->designated_bridge, &br->bridge_id, 8))
24 return 1;
25 }
26
27 return 0;
28}
29
30static void br_hello_timer_expired(struct timer_list *t)
31{
32 struct net_bridge *br = from_timer(br, t, hello_timer);
33
34 br_debug(br, "hello timer expired\n");
35 spin_lock(&br->lock);
36 if (br->dev->flags & IFF_UP) {
37 br_config_bpdu_generation(br);
38
39 if (br->stp_enabled == BR_KERNEL_STP)
40 mod_timer(&br->hello_timer,
41 round_jiffies(jiffies + br->hello_time));
42 }
43 spin_unlock(&br->lock);
44}
45
46static void br_message_age_timer_expired(struct timer_list *t)
47{
48 struct net_bridge_port *p = from_timer(p, t, message_age_timer);
49 struct net_bridge *br = p->br;
50 const bridge_id *id = &p->designated_bridge;
51 int was_root;
52
53 if (p->state == BR_STATE_DISABLED)
54 return;
55
56 br_info(br, "port %u(%s) neighbor %.2x%.2x.%pM lost\n",
57 (unsigned int) p->port_no, p->dev->name,
58 id->prio[0], id->prio[1], &id->addr);
59
60 /*
61 * According to the spec, the message age timer cannot be
62 * running when we are the root bridge. So.. this was_root
63 * check is redundant. I'm leaving it in for now, though.
64 */
65 spin_lock(&br->lock);
66 if (p->state == BR_STATE_DISABLED)
67 goto unlock;
68 was_root = br_is_root_bridge(br);
69
70 br_become_designated_port(p);
71 br_configuration_update(br);
72 br_port_state_selection(br);
73 if (br_is_root_bridge(br) && !was_root)
74 br_become_root_bridge(br);
75 unlock:
76 spin_unlock(&br->lock);
77}
78
79static void br_forward_delay_timer_expired(struct timer_list *t)
80{
81 struct net_bridge_port *p = from_timer(p, t, forward_delay_timer);
82 struct net_bridge *br = p->br;
83
84 br_debug(br, "port %u(%s) forward delay timer\n",
85 (unsigned int) p->port_no, p->dev->name);
86 spin_lock(&br->lock);
87 if (p->state == BR_STATE_LISTENING) {
88 br_set_state(p, BR_STATE_LEARNING);
89 mod_timer(&p->forward_delay_timer,
90 jiffies + br->forward_delay);
91 } else if (p->state == BR_STATE_LEARNING) {
92 br_set_state(p, BR_STATE_FORWARDING);
93 if (br_is_designated_for_some_port(br))
94 br_topology_change_detection(br);
95 netif_carrier_on(br->dev);
96 }
97 rcu_read_lock();
98 br_ifinfo_notify(RTM_NEWLINK, NULL, p);
99 rcu_read_unlock();
100 spin_unlock(&br->lock);
101}
102
103static void br_tcn_timer_expired(struct timer_list *t)
104{
105 struct net_bridge *br = from_timer(br, t, tcn_timer);
106
107 br_debug(br, "tcn timer expired\n");
108 spin_lock(&br->lock);
109 if (!br_is_root_bridge(br) && (br->dev->flags & IFF_UP)) {
110 br_transmit_tcn(br);
111
112 mod_timer(&br->tcn_timer, jiffies + br->bridge_hello_time);
113 }
114 spin_unlock(&br->lock);
115}
116
117static void br_topology_change_timer_expired(struct timer_list *t)
118{
119 struct net_bridge *br = from_timer(br, t, topology_change_timer);
120
121 br_debug(br, "topo change timer expired\n");
122 spin_lock(&br->lock);
123 br->topology_change_detected = 0;
124 __br_set_topology_change(br, 0);
125 spin_unlock(&br->lock);
126}
127
128static void br_hold_timer_expired(struct timer_list *t)
129{
130 struct net_bridge_port *p = from_timer(p, t, hold_timer);
131
132 br_debug(p->br, "port %u(%s) hold timer expired\n",
133 (unsigned int) p->port_no, p->dev->name);
134
135 spin_lock(&p->br->lock);
136 if (p->config_pending)
137 br_transmit_config(p);
138 spin_unlock(&p->br->lock);
139}
140
141void br_stp_timer_init(struct net_bridge *br)
142{
143 timer_setup(&br->hello_timer, br_hello_timer_expired, 0);
144 timer_setup(&br->tcn_timer, br_tcn_timer_expired, 0);
145 timer_setup(&br->topology_change_timer,
146 br_topology_change_timer_expired, 0);
147}
148
149void br_stp_port_timer_init(struct net_bridge_port *p)
150{
151 timer_setup(&p->message_age_timer, br_message_age_timer_expired, 0);
152 timer_setup(&p->forward_delay_timer, br_forward_delay_timer_expired, 0);
153 timer_setup(&p->hold_timer, br_hold_timer_expired, 0);
154}
155
156/* Report ticks left (in USER_HZ) used for API */
157unsigned long br_timer_value(const struct timer_list *timer)
158{
159 return timer_pending(timer)
160 ? jiffies_delta_to_clock_t(timer->expires - jiffies) : 0;
161}