1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Spanning tree protocol; generic parts |
4 | * Linux ethernet bridge |
5 | * |
6 | * Authors: |
7 | * Lennert Buytenhek <buytenh@gnu.org> |
8 | */ |
9 | #include <linux/kernel.h> |
10 | #include <linux/rculist.h> |
11 | #include <net/switchdev.h> |
12 | |
13 | #include "br_private.h" |
14 | #include "br_private_stp.h" |
15 | |
16 | /* since time values in bpdu are in jiffies and then scaled (1/256) |
17 | * before sending, make sure that is at least one STP tick. |
18 | */ |
19 | #define MESSAGE_AGE_INCR ((HZ / 256) + 1) |
20 | |
21 | static const char *const br_port_state_names[] = { |
22 | [BR_STATE_DISABLED] = "disabled" , |
23 | [BR_STATE_LISTENING] = "listening" , |
24 | [BR_STATE_LEARNING] = "learning" , |
25 | [BR_STATE_FORWARDING] = "forwarding" , |
26 | [BR_STATE_BLOCKING] = "blocking" , |
27 | }; |
28 | |
29 | void br_set_state(struct net_bridge_port *p, unsigned int state) |
30 | { |
31 | struct switchdev_attr attr = { |
32 | .orig_dev = p->dev, |
33 | .id = SWITCHDEV_ATTR_ID_PORT_STP_STATE, |
34 | .flags = SWITCHDEV_F_DEFER, |
35 | .u.stp_state = state, |
36 | }; |
37 | int err; |
38 | |
39 | /* Don't change the state of the ports if they are driven by a different |
40 | * protocol. |
41 | */ |
42 | if (p->flags & BR_MRP_AWARE) |
43 | return; |
44 | |
45 | p->state = state; |
46 | if (br_opt_get(br: p->br, opt: BROPT_MST_ENABLED)) { |
47 | err = br_mst_set_state(p, msti: 0, state, NULL); |
48 | if (err) |
49 | br_warn(p->br, "error setting MST state on port %u(%s)\n" , |
50 | p->port_no, netdev_name(p->dev)); |
51 | } |
52 | err = switchdev_port_attr_set(dev: p->dev, attr: &attr, NULL); |
53 | if (err && err != -EOPNOTSUPP) |
54 | br_warn(p->br, "error setting offload STP state on port %u(%s)\n" , |
55 | (unsigned int) p->port_no, p->dev->name); |
56 | else |
57 | br_info(p->br, "port %u(%s) entered %s state\n" , |
58 | (unsigned int) p->port_no, p->dev->name, |
59 | br_port_state_names[p->state]); |
60 | |
61 | if (p->br->stp_enabled == BR_KERNEL_STP) { |
62 | switch (p->state) { |
63 | case BR_STATE_BLOCKING: |
64 | p->stp_xstats.transition_blk++; |
65 | break; |
66 | case BR_STATE_FORWARDING: |
67 | p->stp_xstats.transition_fwd++; |
68 | break; |
69 | } |
70 | } |
71 | } |
72 | |
73 | u8 br_port_get_stp_state(const struct net_device *dev) |
74 | { |
75 | struct net_bridge_port *p; |
76 | |
77 | ASSERT_RTNL(); |
78 | |
79 | p = br_port_get_rtnl(dev); |
80 | if (!p) |
81 | return BR_STATE_DISABLED; |
82 | |
83 | return p->state; |
84 | } |
85 | EXPORT_SYMBOL_GPL(br_port_get_stp_state); |
86 | |
87 | /* called under bridge lock */ |
88 | struct net_bridge_port *br_get_port(struct net_bridge *br, u16 port_no) |
89 | { |
90 | struct net_bridge_port *p; |
91 | |
92 | list_for_each_entry_rcu(p, &br->port_list, list, |
93 | lockdep_is_held(&br->lock)) { |
94 | if (p->port_no == port_no) |
95 | return p; |
96 | } |
97 | |
98 | return NULL; |
99 | } |
100 | |
101 | /* called under bridge lock */ |
102 | static int br_should_become_root_port(const struct net_bridge_port *p, |
103 | u16 root_port) |
104 | { |
105 | struct net_bridge *br; |
106 | struct net_bridge_port *rp; |
107 | int t; |
108 | |
109 | br = p->br; |
110 | if (p->state == BR_STATE_DISABLED || |
111 | br_is_designated_port(p)) |
112 | return 0; |
113 | |
114 | if (memcmp(p: &br->bridge_id, q: &p->designated_root, size: 8) <= 0) |
115 | return 0; |
116 | |
117 | if (!root_port) |
118 | return 1; |
119 | |
120 | rp = br_get_port(br, port_no: root_port); |
121 | |
122 | t = memcmp(p: &p->designated_root, q: &rp->designated_root, size: 8); |
123 | if (t < 0) |
124 | return 1; |
125 | else if (t > 0) |
126 | return 0; |
127 | |
128 | if (p->designated_cost + p->path_cost < |
129 | rp->designated_cost + rp->path_cost) |
130 | return 1; |
131 | else if (p->designated_cost + p->path_cost > |
132 | rp->designated_cost + rp->path_cost) |
133 | return 0; |
134 | |
135 | t = memcmp(p: &p->designated_bridge, q: &rp->designated_bridge, size: 8); |
136 | if (t < 0) |
137 | return 1; |
138 | else if (t > 0) |
139 | return 0; |
140 | |
141 | if (p->designated_port < rp->designated_port) |
142 | return 1; |
143 | else if (p->designated_port > rp->designated_port) |
144 | return 0; |
145 | |
146 | if (p->port_id < rp->port_id) |
147 | return 1; |
148 | |
149 | return 0; |
150 | } |
151 | |
152 | static void br_root_port_block(const struct net_bridge *br, |
153 | struct net_bridge_port *p) |
154 | { |
155 | |
156 | br_notice(br, "port %u(%s) tried to become root port (blocked)" , |
157 | (unsigned int) p->port_no, p->dev->name); |
158 | |
159 | br_set_state(p, BR_STATE_LISTENING); |
160 | br_ifinfo_notify(RTM_NEWLINK, NULL, port: p); |
161 | |
162 | if (br->forward_delay > 0) |
163 | mod_timer(timer: &p->forward_delay_timer, expires: jiffies + br->forward_delay); |
164 | } |
165 | |
166 | /* called under bridge lock */ |
167 | static void br_root_selection(struct net_bridge *br) |
168 | { |
169 | struct net_bridge_port *p; |
170 | u16 root_port = 0; |
171 | |
172 | list_for_each_entry(p, &br->port_list, list) { |
173 | if (!br_should_become_root_port(p, root_port)) |
174 | continue; |
175 | |
176 | if (p->flags & BR_ROOT_BLOCK) |
177 | br_root_port_block(br, p); |
178 | else |
179 | root_port = p->port_no; |
180 | } |
181 | |
182 | br->root_port = root_port; |
183 | |
184 | if (!root_port) { |
185 | br->designated_root = br->bridge_id; |
186 | br->root_path_cost = 0; |
187 | } else { |
188 | p = br_get_port(br, port_no: root_port); |
189 | br->designated_root = p->designated_root; |
190 | br->root_path_cost = p->designated_cost + p->path_cost; |
191 | } |
192 | } |
193 | |
194 | /* called under bridge lock */ |
195 | void br_become_root_bridge(struct net_bridge *br) |
196 | { |
197 | br->max_age = br->bridge_max_age; |
198 | br->hello_time = br->bridge_hello_time; |
199 | br->forward_delay = br->bridge_forward_delay; |
200 | br_topology_change_detection(br); |
201 | del_timer(timer: &br->tcn_timer); |
202 | |
203 | if (br->dev->flags & IFF_UP) { |
204 | br_config_bpdu_generation(br); |
205 | mod_timer(timer: &br->hello_timer, expires: jiffies + br->hello_time); |
206 | } |
207 | } |
208 | |
209 | /* called under bridge lock */ |
210 | void br_transmit_config(struct net_bridge_port *p) |
211 | { |
212 | struct br_config_bpdu bpdu; |
213 | struct net_bridge *br; |
214 | |
215 | if (timer_pending(timer: &p->hold_timer)) { |
216 | p->config_pending = 1; |
217 | return; |
218 | } |
219 | |
220 | br = p->br; |
221 | |
222 | bpdu.topology_change = br->topology_change; |
223 | bpdu.topology_change_ack = p->topology_change_ack; |
224 | bpdu.root = br->designated_root; |
225 | bpdu.root_path_cost = br->root_path_cost; |
226 | bpdu.bridge_id = br->bridge_id; |
227 | bpdu.port_id = p->port_id; |
228 | if (br_is_root_bridge(br)) |
229 | bpdu.message_age = 0; |
230 | else { |
231 | struct net_bridge_port *root |
232 | = br_get_port(br, port_no: br->root_port); |
233 | bpdu.message_age = (jiffies - root->designated_age) |
234 | + MESSAGE_AGE_INCR; |
235 | } |
236 | bpdu.max_age = br->max_age; |
237 | bpdu.hello_time = br->hello_time; |
238 | bpdu.forward_delay = br->forward_delay; |
239 | |
240 | if (bpdu.message_age < br->max_age) { |
241 | br_send_config_bpdu(p, &bpdu); |
242 | p->topology_change_ack = 0; |
243 | p->config_pending = 0; |
244 | if (p->br->stp_enabled == BR_KERNEL_STP) |
245 | mod_timer(timer: &p->hold_timer, |
246 | expires: round_jiffies(j: jiffies + BR_HOLD_TIME)); |
247 | } |
248 | } |
249 | |
250 | /* called under bridge lock */ |
251 | static void br_record_config_information(struct net_bridge_port *p, |
252 | const struct br_config_bpdu *bpdu) |
253 | { |
254 | p->designated_root = bpdu->root; |
255 | p->designated_cost = bpdu->root_path_cost; |
256 | p->designated_bridge = bpdu->bridge_id; |
257 | p->designated_port = bpdu->port_id; |
258 | p->designated_age = jiffies - bpdu->message_age; |
259 | |
260 | mod_timer(timer: &p->message_age_timer, expires: jiffies |
261 | + (bpdu->max_age - bpdu->message_age)); |
262 | } |
263 | |
264 | /* called under bridge lock */ |
265 | static void br_record_config_timeout_values(struct net_bridge *br, |
266 | const struct br_config_bpdu *bpdu) |
267 | { |
268 | br->max_age = bpdu->max_age; |
269 | br->hello_time = bpdu->hello_time; |
270 | br->forward_delay = bpdu->forward_delay; |
271 | __br_set_topology_change(br, val: bpdu->topology_change); |
272 | } |
273 | |
274 | /* called under bridge lock */ |
275 | void br_transmit_tcn(struct net_bridge *br) |
276 | { |
277 | struct net_bridge_port *p; |
278 | |
279 | p = br_get_port(br, port_no: br->root_port); |
280 | if (p) |
281 | br_send_tcn_bpdu(p); |
282 | else |
283 | br_notice(br, "root port %u not found for topology notice\n" , |
284 | br->root_port); |
285 | } |
286 | |
287 | /* called under bridge lock */ |
288 | static int br_should_become_designated_port(const struct net_bridge_port *p) |
289 | { |
290 | struct net_bridge *br; |
291 | int t; |
292 | |
293 | br = p->br; |
294 | if (br_is_designated_port(p)) |
295 | return 1; |
296 | |
297 | if (memcmp(p: &p->designated_root, q: &br->designated_root, size: 8)) |
298 | return 1; |
299 | |
300 | if (br->root_path_cost < p->designated_cost) |
301 | return 1; |
302 | else if (br->root_path_cost > p->designated_cost) |
303 | return 0; |
304 | |
305 | t = memcmp(p: &br->bridge_id, q: &p->designated_bridge, size: 8); |
306 | if (t < 0) |
307 | return 1; |
308 | else if (t > 0) |
309 | return 0; |
310 | |
311 | if (p->port_id < p->designated_port) |
312 | return 1; |
313 | |
314 | return 0; |
315 | } |
316 | |
317 | /* called under bridge lock */ |
318 | static void br_designated_port_selection(struct net_bridge *br) |
319 | { |
320 | struct net_bridge_port *p; |
321 | |
322 | list_for_each_entry(p, &br->port_list, list) { |
323 | if (p->state != BR_STATE_DISABLED && |
324 | br_should_become_designated_port(p)) |
325 | br_become_designated_port(p); |
326 | |
327 | } |
328 | } |
329 | |
330 | /* called under bridge lock */ |
331 | static int br_supersedes_port_info(const struct net_bridge_port *p, |
332 | const struct br_config_bpdu *bpdu) |
333 | { |
334 | int t; |
335 | |
336 | t = memcmp(p: &bpdu->root, q: &p->designated_root, size: 8); |
337 | if (t < 0) |
338 | return 1; |
339 | else if (t > 0) |
340 | return 0; |
341 | |
342 | if (bpdu->root_path_cost < p->designated_cost) |
343 | return 1; |
344 | else if (bpdu->root_path_cost > p->designated_cost) |
345 | return 0; |
346 | |
347 | t = memcmp(p: &bpdu->bridge_id, q: &p->designated_bridge, size: 8); |
348 | if (t < 0) |
349 | return 1; |
350 | else if (t > 0) |
351 | return 0; |
352 | |
353 | if (memcmp(p: &bpdu->bridge_id, q: &p->br->bridge_id, size: 8)) |
354 | return 1; |
355 | |
356 | if (bpdu->port_id <= p->designated_port) |
357 | return 1; |
358 | |
359 | return 0; |
360 | } |
361 | |
362 | /* called under bridge lock */ |
363 | static void br_topology_change_acknowledged(struct net_bridge *br) |
364 | { |
365 | br->topology_change_detected = 0; |
366 | del_timer(timer: &br->tcn_timer); |
367 | } |
368 | |
369 | /* called under bridge lock */ |
370 | void br_topology_change_detection(struct net_bridge *br) |
371 | { |
372 | int isroot = br_is_root_bridge(br); |
373 | |
374 | if (br->stp_enabled != BR_KERNEL_STP) |
375 | return; |
376 | |
377 | br_info(br, "topology change detected, %s\n" , |
378 | isroot ? "propagating" : "sending tcn bpdu" ); |
379 | |
380 | if (isroot) { |
381 | __br_set_topology_change(br, val: 1); |
382 | mod_timer(timer: &br->topology_change_timer, expires: jiffies |
383 | + br->bridge_forward_delay + br->bridge_max_age); |
384 | } else if (!br->topology_change_detected) { |
385 | br_transmit_tcn(br); |
386 | mod_timer(timer: &br->tcn_timer, expires: jiffies + br->bridge_hello_time); |
387 | } |
388 | |
389 | br->topology_change_detected = 1; |
390 | } |
391 | |
392 | /* called under bridge lock */ |
393 | void br_config_bpdu_generation(struct net_bridge *br) |
394 | { |
395 | struct net_bridge_port *p; |
396 | |
397 | list_for_each_entry(p, &br->port_list, list) { |
398 | if (p->state != BR_STATE_DISABLED && |
399 | br_is_designated_port(p)) |
400 | br_transmit_config(p); |
401 | } |
402 | } |
403 | |
404 | /* called under bridge lock */ |
405 | static void br_reply(struct net_bridge_port *p) |
406 | { |
407 | br_transmit_config(p); |
408 | } |
409 | |
410 | /* called under bridge lock */ |
411 | void br_configuration_update(struct net_bridge *br) |
412 | { |
413 | br_root_selection(br); |
414 | br_designated_port_selection(br); |
415 | } |
416 | |
417 | /* called under bridge lock */ |
418 | void br_become_designated_port(struct net_bridge_port *p) |
419 | { |
420 | struct net_bridge *br; |
421 | |
422 | br = p->br; |
423 | p->designated_root = br->designated_root; |
424 | p->designated_cost = br->root_path_cost; |
425 | p->designated_bridge = br->bridge_id; |
426 | p->designated_port = p->port_id; |
427 | } |
428 | |
429 | |
430 | /* called under bridge lock */ |
431 | static void br_make_blocking(struct net_bridge_port *p) |
432 | { |
433 | if (p->state != BR_STATE_DISABLED && |
434 | p->state != BR_STATE_BLOCKING) { |
435 | if (p->state == BR_STATE_FORWARDING || |
436 | p->state == BR_STATE_LEARNING) |
437 | br_topology_change_detection(br: p->br); |
438 | |
439 | br_set_state(p, BR_STATE_BLOCKING); |
440 | br_ifinfo_notify(RTM_NEWLINK, NULL, port: p); |
441 | |
442 | del_timer(timer: &p->forward_delay_timer); |
443 | } |
444 | } |
445 | |
446 | /* called under bridge lock */ |
447 | static void br_make_forwarding(struct net_bridge_port *p) |
448 | { |
449 | struct net_bridge *br = p->br; |
450 | |
451 | if (p->state != BR_STATE_BLOCKING) |
452 | return; |
453 | |
454 | if (br->stp_enabled == BR_NO_STP || br->forward_delay == 0) { |
455 | br_set_state(p, BR_STATE_FORWARDING); |
456 | br_topology_change_detection(br); |
457 | del_timer(timer: &p->forward_delay_timer); |
458 | } else if (br->stp_enabled == BR_KERNEL_STP) |
459 | br_set_state(p, BR_STATE_LISTENING); |
460 | else |
461 | br_set_state(p, BR_STATE_LEARNING); |
462 | |
463 | br_ifinfo_notify(RTM_NEWLINK, NULL, port: p); |
464 | |
465 | if (br->forward_delay != 0) |
466 | mod_timer(timer: &p->forward_delay_timer, expires: jiffies + br->forward_delay); |
467 | } |
468 | |
469 | /* called under bridge lock */ |
470 | void br_port_state_selection(struct net_bridge *br) |
471 | { |
472 | struct net_bridge_port *p; |
473 | unsigned int liveports = 0; |
474 | |
475 | list_for_each_entry(p, &br->port_list, list) { |
476 | if (p->state == BR_STATE_DISABLED) |
477 | continue; |
478 | |
479 | /* Don't change port states if userspace is handling STP */ |
480 | if (br->stp_enabled != BR_USER_STP) { |
481 | if (p->port_no == br->root_port) { |
482 | p->config_pending = 0; |
483 | p->topology_change_ack = 0; |
484 | br_make_forwarding(p); |
485 | } else if (br_is_designated_port(p)) { |
486 | del_timer(timer: &p->message_age_timer); |
487 | br_make_forwarding(p); |
488 | } else { |
489 | p->config_pending = 0; |
490 | p->topology_change_ack = 0; |
491 | br_make_blocking(p); |
492 | } |
493 | } |
494 | |
495 | if (p->state != BR_STATE_BLOCKING) |
496 | br_multicast_enable_port(port: p); |
497 | /* Multicast is not disabled for the port when it goes in |
498 | * blocking state because the timers will expire and stop by |
499 | * themselves without sending more queries. |
500 | */ |
501 | if (p->state == BR_STATE_FORWARDING) |
502 | ++liveports; |
503 | } |
504 | |
505 | if (liveports == 0) |
506 | netif_carrier_off(dev: br->dev); |
507 | else |
508 | netif_carrier_on(dev: br->dev); |
509 | } |
510 | |
511 | /* called under bridge lock */ |
512 | static void br_topology_change_acknowledge(struct net_bridge_port *p) |
513 | { |
514 | p->topology_change_ack = 1; |
515 | br_transmit_config(p); |
516 | } |
517 | |
518 | /* called under bridge lock */ |
519 | void br_received_config_bpdu(struct net_bridge_port *p, |
520 | const struct br_config_bpdu *bpdu) |
521 | { |
522 | struct net_bridge *br; |
523 | int was_root; |
524 | |
525 | p->stp_xstats.rx_bpdu++; |
526 | |
527 | br = p->br; |
528 | was_root = br_is_root_bridge(br); |
529 | |
530 | if (br_supersedes_port_info(p, bpdu)) { |
531 | br_record_config_information(p, bpdu); |
532 | br_configuration_update(br); |
533 | br_port_state_selection(br); |
534 | |
535 | if (!br_is_root_bridge(br) && was_root) { |
536 | del_timer(timer: &br->hello_timer); |
537 | if (br->topology_change_detected) { |
538 | del_timer(timer: &br->topology_change_timer); |
539 | br_transmit_tcn(br); |
540 | |
541 | mod_timer(timer: &br->tcn_timer, |
542 | expires: jiffies + br->bridge_hello_time); |
543 | } |
544 | } |
545 | |
546 | if (p->port_no == br->root_port) { |
547 | br_record_config_timeout_values(br, bpdu); |
548 | br_config_bpdu_generation(br); |
549 | if (bpdu->topology_change_ack) |
550 | br_topology_change_acknowledged(br); |
551 | } |
552 | } else if (br_is_designated_port(p)) { |
553 | br_reply(p); |
554 | } |
555 | } |
556 | |
557 | /* called under bridge lock */ |
558 | void br_received_tcn_bpdu(struct net_bridge_port *p) |
559 | { |
560 | p->stp_xstats.rx_tcn++; |
561 | |
562 | if (br_is_designated_port(p)) { |
563 | br_info(p->br, "port %u(%s) received tcn bpdu\n" , |
564 | (unsigned int) p->port_no, p->dev->name); |
565 | |
566 | br_topology_change_detection(br: p->br); |
567 | br_topology_change_acknowledge(p); |
568 | } |
569 | } |
570 | |
571 | /* Change bridge STP parameter */ |
572 | int br_set_hello_time(struct net_bridge *br, unsigned long val) |
573 | { |
574 | unsigned long t = clock_t_to_jiffies(x: val); |
575 | |
576 | if (t < BR_MIN_HELLO_TIME || t > BR_MAX_HELLO_TIME) |
577 | return -ERANGE; |
578 | |
579 | spin_lock_bh(lock: &br->lock); |
580 | br->bridge_hello_time = t; |
581 | if (br_is_root_bridge(br)) |
582 | br->hello_time = br->bridge_hello_time; |
583 | spin_unlock_bh(lock: &br->lock); |
584 | return 0; |
585 | } |
586 | |
587 | int br_set_max_age(struct net_bridge *br, unsigned long val) |
588 | { |
589 | unsigned long t = clock_t_to_jiffies(x: val); |
590 | |
591 | if (t < BR_MIN_MAX_AGE || t > BR_MAX_MAX_AGE) |
592 | return -ERANGE; |
593 | |
594 | spin_lock_bh(lock: &br->lock); |
595 | br->bridge_max_age = t; |
596 | if (br_is_root_bridge(br)) |
597 | br->max_age = br->bridge_max_age; |
598 | spin_unlock_bh(lock: &br->lock); |
599 | return 0; |
600 | |
601 | } |
602 | |
603 | /* called under bridge lock */ |
604 | int __set_ageing_time(struct net_device *dev, unsigned long t) |
605 | { |
606 | struct switchdev_attr attr = { |
607 | .orig_dev = dev, |
608 | .id = SWITCHDEV_ATTR_ID_BRIDGE_AGEING_TIME, |
609 | .flags = SWITCHDEV_F_SKIP_EOPNOTSUPP | SWITCHDEV_F_DEFER, |
610 | .u.ageing_time = jiffies_to_clock_t(x: t), |
611 | }; |
612 | int err; |
613 | |
614 | err = switchdev_port_attr_set(dev, attr: &attr, NULL); |
615 | if (err && err != -EOPNOTSUPP) |
616 | return err; |
617 | |
618 | return 0; |
619 | } |
620 | |
621 | /* Set time interval that dynamic forwarding entries live |
622 | * For pure software bridge, allow values outside the 802.1 |
623 | * standard specification for special cases: |
624 | * 0 - entry never ages (all permanent) |
625 | * 1 - entry disappears (no persistence) |
626 | * |
627 | * Offloaded switch entries maybe more restrictive |
628 | */ |
629 | int br_set_ageing_time(struct net_bridge *br, clock_t ageing_time) |
630 | { |
631 | unsigned long t = clock_t_to_jiffies(x: ageing_time); |
632 | int err; |
633 | |
634 | err = __set_ageing_time(dev: br->dev, t); |
635 | if (err) |
636 | return err; |
637 | |
638 | spin_lock_bh(lock: &br->lock); |
639 | br->bridge_ageing_time = t; |
640 | br->ageing_time = t; |
641 | spin_unlock_bh(lock: &br->lock); |
642 | |
643 | mod_delayed_work(wq: system_long_wq, dwork: &br->gc_work, delay: 0); |
644 | |
645 | return 0; |
646 | } |
647 | |
648 | clock_t br_get_ageing_time(const struct net_device *br_dev) |
649 | { |
650 | const struct net_bridge *br; |
651 | |
652 | if (!netif_is_bridge_master(dev: br_dev)) |
653 | return 0; |
654 | |
655 | br = netdev_priv(dev: br_dev); |
656 | |
657 | return jiffies_to_clock_t(x: br->ageing_time); |
658 | } |
659 | EXPORT_SYMBOL_GPL(br_get_ageing_time); |
660 | |
661 | /* called under bridge lock */ |
662 | void __br_set_topology_change(struct net_bridge *br, unsigned char val) |
663 | { |
664 | unsigned long t; |
665 | int err; |
666 | |
667 | if (br->stp_enabled == BR_KERNEL_STP && br->topology_change != val) { |
668 | /* On topology change, set the bridge ageing time to twice the |
669 | * forward delay. Otherwise, restore its default ageing time. |
670 | */ |
671 | |
672 | if (val) { |
673 | t = 2 * br->forward_delay; |
674 | br_debug(br, "decreasing ageing time to %lu\n" , t); |
675 | } else { |
676 | t = br->bridge_ageing_time; |
677 | br_debug(br, "restoring ageing time to %lu\n" , t); |
678 | } |
679 | |
680 | err = __set_ageing_time(dev: br->dev, t); |
681 | if (err) |
682 | br_warn(br, "error offloading ageing time\n" ); |
683 | else |
684 | br->ageing_time = t; |
685 | } |
686 | |
687 | br->topology_change = val; |
688 | } |
689 | |
690 | void __br_set_forward_delay(struct net_bridge *br, unsigned long t) |
691 | { |
692 | br->bridge_forward_delay = t; |
693 | if (br_is_root_bridge(br)) |
694 | br->forward_delay = br->bridge_forward_delay; |
695 | } |
696 | |
697 | int br_set_forward_delay(struct net_bridge *br, unsigned long val) |
698 | { |
699 | unsigned long t = clock_t_to_jiffies(x: val); |
700 | int err = -ERANGE; |
701 | |
702 | spin_lock_bh(lock: &br->lock); |
703 | if (br->stp_enabled != BR_NO_STP && |
704 | (t < BR_MIN_FORWARD_DELAY || t > BR_MAX_FORWARD_DELAY)) |
705 | goto unlock; |
706 | |
707 | __br_set_forward_delay(br, t); |
708 | err = 0; |
709 | |
710 | unlock: |
711 | spin_unlock_bh(lock: &br->lock); |
712 | return err; |
713 | } |
714 | |