Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-serial
[linux-2.6] / net / bridge / br_stp_if.c
1 /*
2  *      Spanning tree protocol; interface code
3  *      Linux ethernet bridge
4  *
5  *      Authors:
6  *      Lennert Buytenhek               <buytenh@gnu.org>
7  *
8  *      $Id: br_stp_if.c,v 1.4 2001/04/14 21:14:39 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/smp_lock.h>
18 #include <linux/etherdevice.h>
19 #include <linux/rtnetlink.h>
20
21 #include "br_private.h"
22 #include "br_private_stp.h"
23
24
25 /* Port id is composed of priority and port number.
26  * NB: least significant bits of priority are dropped to
27  *     make room for more ports.
28  */
29 static inline port_id br_make_port_id(__u8 priority, __u16 port_no)
30 {
31         return ((u16)priority << BR_PORT_BITS) 
32                 | (port_no & ((1<<BR_PORT_BITS)-1));
33 }
34
35 /* called under bridge lock */
36 void br_init_port(struct net_bridge_port *p)
37 {
38         p->port_id = br_make_port_id(p->priority, p->port_no);
39         br_become_designated_port(p);
40         p->state = BR_STATE_BLOCKING;
41         p->topology_change_ack = 0;
42         p->config_pending = 0;
43 }
44
45 /* called under bridge lock */
46 void br_stp_enable_bridge(struct net_bridge *br)
47 {
48         struct net_bridge_port *p;
49
50         spin_lock_bh(&br->lock);
51         mod_timer(&br->hello_timer, jiffies + br->hello_time);
52         mod_timer(&br->gc_timer, jiffies + HZ/10);
53         
54         br_config_bpdu_generation(br);
55
56         list_for_each_entry(p, &br->port_list, list) {
57                 if ((p->dev->flags & IFF_UP) && netif_carrier_ok(p->dev))
58                         br_stp_enable_port(p);
59
60         }
61         spin_unlock_bh(&br->lock);
62 }
63
64 /* NO locks held */
65 void br_stp_disable_bridge(struct net_bridge *br)
66 {
67         struct net_bridge_port *p;
68
69         spin_lock_bh(&br->lock);
70         list_for_each_entry(p, &br->port_list, list) {
71                 if (p->state != BR_STATE_DISABLED)
72                         br_stp_disable_port(p);
73
74         }
75
76         br->topology_change = 0;
77         br->topology_change_detected = 0;
78         spin_unlock_bh(&br->lock);
79
80         del_timer_sync(&br->hello_timer);
81         del_timer_sync(&br->topology_change_timer);
82         del_timer_sync(&br->tcn_timer);
83         del_timer_sync(&br->gc_timer);
84 }
85
86 /* called under bridge lock */
87 void br_stp_enable_port(struct net_bridge_port *p)
88 {
89         br_init_port(p);
90         br_ifinfo_notify(RTM_NEWLINK, p);
91         br_port_state_selection(p->br);
92 }
93
94 /* called under bridge lock */
95 void br_stp_disable_port(struct net_bridge_port *p)
96 {
97         struct net_bridge *br;
98         int wasroot;
99
100         br = p->br;
101         printk(KERN_INFO "%s: port %i(%s) entering %s state\n",
102                br->dev->name, p->port_no, p->dev->name, "disabled");
103
104         br_ifinfo_notify(RTM_DELLINK, p);
105
106         wasroot = br_is_root_bridge(br);
107         br_become_designated_port(p);
108         p->state = BR_STATE_DISABLED;
109         p->topology_change_ack = 0;
110         p->config_pending = 0;
111
112         del_timer(&p->message_age_timer);
113         del_timer(&p->forward_delay_timer);
114         del_timer(&p->hold_timer);
115
116         br_configuration_update(br);
117
118         br_port_state_selection(br);
119
120         if (br_is_root_bridge(br) && !wasroot)
121                 br_become_root_bridge(br);
122 }
123
124 /* called under bridge lock */
125 void br_stp_change_bridge_id(struct net_bridge *br, const unsigned char *addr)
126 {
127         unsigned char oldaddr[6];
128         struct net_bridge_port *p;
129         int wasroot;
130
131         wasroot = br_is_root_bridge(br);
132
133         memcpy(oldaddr, br->bridge_id.addr, ETH_ALEN);
134         memcpy(br->bridge_id.addr, addr, ETH_ALEN);
135         memcpy(br->dev->dev_addr, addr, ETH_ALEN);
136
137         list_for_each_entry(p, &br->port_list, list) {
138                 if (!compare_ether_addr(p->designated_bridge.addr, oldaddr))
139                         memcpy(p->designated_bridge.addr, addr, ETH_ALEN);
140
141                 if (!compare_ether_addr(p->designated_root.addr, oldaddr))
142                         memcpy(p->designated_root.addr, addr, ETH_ALEN);
143
144         }
145
146         br_configuration_update(br);
147         br_port_state_selection(br);
148         if (br_is_root_bridge(br) && !wasroot)
149                 br_become_root_bridge(br);
150 }
151
152 static const unsigned char br_mac_zero[6];
153
154 /* called under bridge lock */
155 void br_stp_recalculate_bridge_id(struct net_bridge *br)
156 {
157         const unsigned char *addr = br_mac_zero;
158         struct net_bridge_port *p;
159
160         list_for_each_entry(p, &br->port_list, list) {
161                 if (addr == br_mac_zero ||
162                     memcmp(p->dev->dev_addr, addr, ETH_ALEN) < 0)
163                         addr = p->dev->dev_addr;
164
165         }
166
167         if (compare_ether_addr(br->bridge_id.addr, addr))
168                 br_stp_change_bridge_id(br, addr);
169 }
170
171 /* called under bridge lock */
172 void br_stp_set_bridge_priority(struct net_bridge *br, u16 newprio)
173 {
174         struct net_bridge_port *p;
175         int wasroot;
176
177         wasroot = br_is_root_bridge(br);
178
179         list_for_each_entry(p, &br->port_list, list) {
180                 if (p->state != BR_STATE_DISABLED &&
181                     br_is_designated_port(p)) {
182                         p->designated_bridge.prio[0] = (newprio >> 8) & 0xFF;
183                         p->designated_bridge.prio[1] = newprio & 0xFF;
184                 }
185
186         }
187
188         br->bridge_id.prio[0] = (newprio >> 8) & 0xFF;
189         br->bridge_id.prio[1] = newprio & 0xFF;
190         br_configuration_update(br);
191         br_port_state_selection(br);
192         if (br_is_root_bridge(br) && !wasroot)
193                 br_become_root_bridge(br);
194 }
195
196 /* called under bridge lock */
197 void br_stp_set_port_priority(struct net_bridge_port *p, u8 newprio)
198 {
199         port_id new_port_id = br_make_port_id(newprio, p->port_no);
200
201         if (br_is_designated_port(p))
202                 p->designated_port = new_port_id;
203
204         p->port_id = new_port_id;
205         p->priority = newprio;
206         if (!memcmp(&p->br->bridge_id, &p->designated_bridge, 8) &&
207             p->port_id < p->designated_port) {
208                 br_become_designated_port(p);
209                 br_port_state_selection(p->br);
210         }
211 }
212
213 /* called under bridge lock */
214 void br_stp_set_path_cost(struct net_bridge_port *p, u32 path_cost)
215 {
216         p->path_cost = path_cost;
217         br_configuration_update(p->br);
218         br_port_state_selection(p->br);
219 }
220
221 ssize_t br_show_bridge_id(char *buf, const struct bridge_id *id)
222 {
223         return sprintf(buf, "%.2x%.2x.%.2x%.2x%.2x%.2x%.2x%.2x\n",
224                id->prio[0], id->prio[1],
225                id->addr[0], id->addr[1], id->addr[2],
226                id->addr[3], id->addr[4], id->addr[5]);
227 }