Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/shaggy...
[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_fdb_delete_by_port(br, p, 0);
117
118         br_configuration_update(br);
119
120         br_port_state_selection(br);
121
122         if (br_is_root_bridge(br) && !wasroot)
123                 br_become_root_bridge(br);
124 }
125
126 /* called under bridge lock */
127 void br_stp_change_bridge_id(struct net_bridge *br, const unsigned char *addr)
128 {
129         unsigned char oldaddr[6];
130         struct net_bridge_port *p;
131         int wasroot;
132
133         wasroot = br_is_root_bridge(br);
134
135         memcpy(oldaddr, br->bridge_id.addr, ETH_ALEN);
136         memcpy(br->bridge_id.addr, addr, ETH_ALEN);
137         memcpy(br->dev->dev_addr, addr, ETH_ALEN);
138
139         list_for_each_entry(p, &br->port_list, list) {
140                 if (!compare_ether_addr(p->designated_bridge.addr, oldaddr))
141                         memcpy(p->designated_bridge.addr, addr, ETH_ALEN);
142
143                 if (!compare_ether_addr(p->designated_root.addr, oldaddr))
144                         memcpy(p->designated_root.addr, addr, ETH_ALEN);
145
146         }
147
148         br_configuration_update(br);
149         br_port_state_selection(br);
150         if (br_is_root_bridge(br) && !wasroot)
151                 br_become_root_bridge(br);
152 }
153
154 static const unsigned char br_mac_zero[6];
155
156 /* called under bridge lock */
157 void br_stp_recalculate_bridge_id(struct net_bridge *br)
158 {
159         const unsigned char *addr = br_mac_zero;
160         struct net_bridge_port *p;
161
162         list_for_each_entry(p, &br->port_list, list) {
163                 if (addr == br_mac_zero ||
164                     memcmp(p->dev->dev_addr, addr, ETH_ALEN) < 0)
165                         addr = p->dev->dev_addr;
166
167         }
168
169         if (compare_ether_addr(br->bridge_id.addr, addr))
170                 br_stp_change_bridge_id(br, addr);
171 }
172
173 /* called under bridge lock */
174 void br_stp_set_bridge_priority(struct net_bridge *br, u16 newprio)
175 {
176         struct net_bridge_port *p;
177         int wasroot;
178
179         wasroot = br_is_root_bridge(br);
180
181         list_for_each_entry(p, &br->port_list, list) {
182                 if (p->state != BR_STATE_DISABLED &&
183                     br_is_designated_port(p)) {
184                         p->designated_bridge.prio[0] = (newprio >> 8) & 0xFF;
185                         p->designated_bridge.prio[1] = newprio & 0xFF;
186                 }
187
188         }
189
190         br->bridge_id.prio[0] = (newprio >> 8) & 0xFF;
191         br->bridge_id.prio[1] = newprio & 0xFF;
192         br_configuration_update(br);
193         br_port_state_selection(br);
194         if (br_is_root_bridge(br) && !wasroot)
195                 br_become_root_bridge(br);
196 }
197
198 /* called under bridge lock */
199 void br_stp_set_port_priority(struct net_bridge_port *p, u8 newprio)
200 {
201         port_id new_port_id = br_make_port_id(newprio, p->port_no);
202
203         if (br_is_designated_port(p))
204                 p->designated_port = new_port_id;
205
206         p->port_id = new_port_id;
207         p->priority = newprio;
208         if (!memcmp(&p->br->bridge_id, &p->designated_bridge, 8) &&
209             p->port_id < p->designated_port) {
210                 br_become_designated_port(p);
211                 br_port_state_selection(p->br);
212         }
213 }
214
215 /* called under bridge lock */
216 void br_stp_set_path_cost(struct net_bridge_port *p, u32 path_cost)
217 {
218         p->path_cost = path_cost;
219         br_configuration_update(p->br);
220         br_port_state_selection(p->br);
221 }
222
223 ssize_t br_show_bridge_id(char *buf, const struct bridge_id *id)
224 {
225         return sprintf(buf, "%.2x%.2x.%.2x%.2x%.2x%.2x%.2x%.2x\n",
226                id->prio[0], id->prio[1],
227                id->addr[0], id->addr[1], id->addr[2],
228                id->addr[3], id->addr[4], id->addr[5]);
229 }