1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
|
/*
* Spanning tree protocol; timer-related code
* Linux ethernet bridge
*
* Authors:
* Lennert Buytenhek <buytenh@gnu.org>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#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;
}
|
