2 * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014 Nicira, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
17 /* Based on sample implementation in 802.1D-1998. Above copyright and license
18 * applies to all modifications. */
23 #include <sys/types.h>
24 #include <netinet/in.h>
25 #include <arpa/inet.h>
28 #include "byte-order.h"
29 #include "connectivity.h"
31 #include "ovs-atomic.h"
36 #include "openvswitch/vlog.h"
38 VLOG_DEFINE_THIS_MODULE(stp);
40 static struct vlog_rate_limit stp_rl = VLOG_RATE_LIMIT_INIT(60, 60);
42 #define STP_PROTOCOL_ID 0x0000
43 #define STP_PROTOCOL_VERSION 0x00
44 #define STP_TYPE_CONFIG 0x00
45 #define STP_TYPE_TCN 0x80
48 struct stp_bpdu_header {
49 ovs_be16 protocol_id; /* STP_PROTOCOL_ID. */
50 uint8_t protocol_version; /* STP_PROTOCOL_VERSION. */
51 uint8_t bpdu_type; /* One of STP_TYPE_*. */
53 BUILD_ASSERT_DECL(sizeof(struct stp_bpdu_header) == 4);
55 enum stp_config_bpdu_flags {
56 STP_CONFIG_TOPOLOGY_CHANGE_ACK = 0x80,
57 STP_CONFIG_TOPOLOGY_CHANGE = 0x01
61 struct stp_config_bpdu {
62 struct stp_bpdu_header header; /* Type STP_TYPE_CONFIG. */
63 uint8_t flags; /* STP_CONFIG_* flags. */
64 ovs_be64 root_id; /* 8.5.1.1: Bridge believed to be root. */
65 ovs_be32 root_path_cost; /* 8.5.1.2: Cost of path to root. */
66 ovs_be64 bridge_id; /* 8.5.1.3: ID of transmitting bridge. */
67 ovs_be16 port_id; /* 8.5.1.4: Port transmitting the BPDU. */
68 ovs_be16 message_age; /* 8.5.1.5: Age of BPDU at tx time. */
69 ovs_be16 max_age; /* 8.5.1.6: Timeout for received data. */
70 ovs_be16 hello_time; /* 8.5.1.7: Time between BPDU generation. */
71 ovs_be16 forward_delay; /* 8.5.1.8: State progression delay. */
73 BUILD_ASSERT_DECL(sizeof(struct stp_config_bpdu) == 35);
77 struct stp_bpdu_header header; /* Type STP_TYPE_TCN. */
79 BUILD_ASSERT_DECL(sizeof(struct stp_tcn_bpdu) == 4);
82 bool active; /* Timer in use? */
83 int value; /* Current value of timer, counting up. */
88 char *port_name; /* Human-readable name for log messages. */
89 void *aux; /* Auxiliary data the user may retrieve. */
90 int port_id; /* 8.5.5.1: Unique port identifier. */
91 enum stp_state state; /* 8.5.5.2: Current state. */
92 int path_cost; /* 8.5.5.3: Cost of tx/rx on this port. */
93 stp_identifier designated_root; /* 8.5.5.4. */
94 int designated_cost; /* 8.5.5.5: Path cost to root on port. */
95 stp_identifier designated_bridge; /* 8.5.5.6. */
96 int designated_port; /* 8.5.5.7: Port to send config msgs on. */
97 bool topology_change_ack; /* 8.5.5.8: Flag for next config BPDU. */
98 bool config_pending; /* 8.5.5.9: Send BPDU when hold expires? */
99 bool change_detection_enabled; /* 8.5.5.10: Detect topology changes? */
101 struct stp_timer message_age_timer; /* 8.5.6.1: Age of received info. */
102 struct stp_timer forward_delay_timer; /* 8.5.6.2: State change timer. */
103 struct stp_timer hold_timer; /* 8.5.6.3: BPDU rate limit timer. */
105 int tx_count; /* Number of BPDUs transmitted. */
106 int rx_count; /* Number of valid BPDUs received. */
107 int error_count; /* Number of bad BPDUs received. */
113 struct ovs_list node; /* Node in all_stps list. */
115 /* Static bridge data. */
116 char *name; /* Human-readable name for log messages. */
117 stp_identifier bridge_id; /* 8.5.3.7: This bridge. */
118 int max_age; /* 8.5.3.4: Time to drop received data. */
119 int hello_time; /* 8.5.3.5: Time between sending BPDUs. */
120 int forward_delay; /* 8.5.3.6: Delay between state changes. */
121 int bridge_max_age; /* 8.5.3.8: max_age when we're root. */
122 int bridge_hello_time; /* 8.5.3.9: hello_time as root. */
123 int bridge_forward_delay; /* 8.5.3.10: forward_delay as root. */
124 int rq_max_age; /* User-requested max age, in ms. */
125 int rq_hello_time; /* User-requested hello time, in ms. */
126 int rq_forward_delay; /* User-requested forward delay, in ms. */
127 int elapsed_remainder; /* Left-over msecs from last stp_tick(). */
129 /* Dynamic bridge data. */
130 stp_identifier designated_root; /* 8.5.3.1: Bridge believed to be root. */
131 unsigned int root_path_cost; /* 8.5.3.2: Cost of path to root. */
132 struct stp_port *root_port; /* 8.5.3.3: Lowest cost port to root. */
133 bool topology_change_detected; /* 8.5.3.11: Detected a topology change? */
134 bool topology_change; /* 8.5.3.12: Received topology change? */
137 struct stp_timer hello_timer; /* 8.5.4.1: Hello timer. */
138 struct stp_timer tcn_timer; /* 8.5.4.2: Topology change timer. */
139 struct stp_timer topology_change_timer; /* 8.5.4.3. */
142 struct stp_port ports[STP_MAX_PORTS];
144 /* Interface to client. */
145 bool fdb_needs_flush; /* MAC learning tables needs flushing. */
146 struct stp_port *first_changed_port;
147 void (*send_bpdu)(struct ofpbuf *bpdu, int port_no, void *aux);
150 struct ovs_refcount ref_cnt;
153 static struct ovs_mutex mutex;
154 static struct ovs_list all_stps__ = OVS_LIST_INITIALIZER(&all_stps__);
155 static struct ovs_list *const all_stps OVS_GUARDED_BY(mutex) = &all_stps__;
157 #define FOR_EACH_ENABLED_PORT(PORT, STP) \
158 for ((PORT) = stp_next_enabled_port((STP), (STP)->ports); \
160 (PORT) = stp_next_enabled_port((STP), (PORT) + 1))
161 static struct stp_port *
162 stp_next_enabled_port(const struct stp *stp, const struct stp_port *port)
165 for (; port < &stp->ports[ARRAY_SIZE(stp->ports)]; port++) {
166 if (port->state != STP_DISABLED) {
167 return CONST_CAST(struct stp_port *, port);
173 #define MESSAGE_AGE_INCREMENT 1
175 static void stp_transmit_config(struct stp_port *) OVS_REQUIRES(mutex);
176 static bool stp_supersedes_port_info(const struct stp_port *,
177 const struct stp_config_bpdu *)
179 static void stp_record_config_information(struct stp_port *,
180 const struct stp_config_bpdu *)
182 static void stp_record_config_timeout_values(struct stp *,
183 const struct stp_config_bpdu *)
185 static bool stp_is_designated_port(const struct stp_port *)
187 static void stp_config_bpdu_generation(struct stp *) OVS_REQUIRES(mutex);
188 static void stp_transmit_tcn(struct stp *) OVS_REQUIRES(mutex);
189 static void stp_configuration_update(struct stp *) OVS_REQUIRES(mutex);
190 static bool stp_supersedes_root(const struct stp_port *root,
191 const struct stp_port *) OVS_REQUIRES(mutex);
192 static void stp_root_selection(struct stp *) OVS_REQUIRES(mutex);
193 static void stp_designated_port_selection(struct stp *) OVS_REQUIRES(mutex);
194 static void stp_become_designated_port(struct stp_port *)
196 static void stp_port_state_selection(struct stp *) OVS_REQUIRES(mutex);
197 static void stp_make_forwarding(struct stp_port *) OVS_REQUIRES(mutex);
198 static void stp_make_blocking(struct stp_port *) OVS_REQUIRES(mutex);
199 static void stp_set_port_state(struct stp_port *, enum stp_state)
201 static void stp_topology_change_detection(struct stp *) OVS_REQUIRES(mutex);
202 static void stp_topology_change_acknowledged(struct stp *)
204 static void stp_acknowledge_topology_change(struct stp_port *)
206 static void stp_received_config_bpdu(struct stp *, struct stp_port *,
207 const struct stp_config_bpdu *)
209 static void stp_received_tcn_bpdu(struct stp *, struct stp_port *)
211 static void stp_hello_timer_expiry(struct stp *) OVS_REQUIRES(mutex);
212 static void stp_message_age_timer_expiry(struct stp_port *)
214 static bool stp_is_designated_for_some_port(const struct stp *)
216 static void stp_forward_delay_timer_expiry(struct stp_port *)
218 static void stp_tcn_timer_expiry(struct stp *) OVS_REQUIRES(mutex);
219 static void stp_topology_change_timer_expiry(struct stp *)
221 static void stp_hold_timer_expiry(struct stp_port *) OVS_REQUIRES(mutex);
222 static void stp_initialize_port(struct stp_port *, enum stp_state)
224 static void stp_become_root_bridge(struct stp *) OVS_REQUIRES(mutex);
225 static void stp_update_bridge_timers(struct stp *) OVS_REQUIRES(mutex);
227 static int clamp(int x, int min, int max);
228 static int ms_to_timer(int ms);
229 static int timer_to_ms(int timer);
230 static void stp_start_timer(struct stp_timer *, int value);
231 static void stp_stop_timer(struct stp_timer *);
232 static bool stp_timer_expired(struct stp_timer *, int elapsed, int timeout);
234 static void stp_send_bpdu(struct stp_port *, const void *, size_t)
236 static void stp_unixctl_tcn(struct unixctl_conn *, int argc,
237 const char *argv[], void *aux);
242 unixctl_command_register("stp/tcn", "[bridge]", 0, 1, stp_unixctl_tcn,
246 /* Creates and returns a new STP instance that initially has no ports enabled.
248 * 'bridge_id' should be a 48-bit MAC address as returned by
249 * eth_addr_to_uint64(). 'bridge_id' may also have a priority value in its top
250 * 16 bits; if those bits are set to 0, STP_DEFAULT_BRIDGE_PRIORITY is used.
251 * (This priority may be changed with stp_set_bridge_priority().)
253 * When the bridge needs to send out a BPDU, it calls 'send_bpdu'. This
254 * callback may be called from stp_tick() or stp_received_bpdu(). The
255 * arguments to 'send_bpdu' are an STP BPDU encapsulated in 'bpdu',
256 * the spanning tree port number 'port_no' that should transmit the
257 * packet, and auxiliary data to be passed to the callback in 'aux'.
260 stp_create(const char *name, stp_identifier bridge_id,
261 void (*send_bpdu)(struct ofpbuf *bpdu, int port_no, void *aux),
264 static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER;
268 if (ovsthread_once_start(&once)) {
269 /* We need a recursive mutex because stp_send_bpdu() could loop back
270 * into the stp module through a patch port. This happens
271 * intentionally as part of the unit tests. Ideally we'd ditch
272 * the call back function, but for now this is what we have. */
273 ovs_mutex_init_recursive(&mutex);
274 ovsthread_once_done(&once);
277 ovs_mutex_lock(&mutex);
278 stp = xzalloc(sizeof *stp);
279 stp->name = xstrdup(name);
280 stp->bridge_id = bridge_id;
281 if (!(stp->bridge_id >> 48)) {
282 stp->bridge_id |= (uint64_t) STP_DEFAULT_BRIDGE_PRIORITY << 48;
285 stp->rq_max_age = STP_DEFAULT_MAX_AGE;
286 stp->rq_hello_time = STP_DEFAULT_HELLO_TIME;
287 stp->rq_forward_delay = STP_DEFAULT_FWD_DELAY;
288 stp_update_bridge_timers(stp);
289 stp->max_age = stp->bridge_max_age;
290 stp->hello_time = stp->bridge_hello_time;
291 stp->forward_delay = stp->bridge_forward_delay;
293 stp->designated_root = stp->bridge_id;
294 stp->root_path_cost = 0;
295 stp->root_port = NULL;
296 stp->topology_change_detected = false;
297 stp->topology_change = false;
299 stp_stop_timer(&stp->tcn_timer);
300 stp_stop_timer(&stp->topology_change_timer);
301 stp_start_timer(&stp->hello_timer, 0);
303 stp->send_bpdu = send_bpdu;
306 stp->first_changed_port = &stp->ports[ARRAY_SIZE(stp->ports)];
307 for (p = stp->ports; p < &stp->ports[ARRAY_SIZE(stp->ports)]; p++) {
309 p->port_id = (stp_port_no(p) + 1) | (STP_DEFAULT_PORT_PRIORITY << 8);
310 p->path_cost = 19; /* Recommended default for 100 Mb/s link. */
311 stp_initialize_port(p, STP_DISABLED);
313 ovs_refcount_init(&stp->ref_cnt);
315 list_push_back(all_stps, &stp->node);
316 ovs_mutex_unlock(&mutex);
321 stp_ref(const struct stp *stp_)
323 struct stp *stp = CONST_CAST(struct stp *, stp_);
325 ovs_refcount_ref(&stp->ref_cnt);
330 /* Destroys 'stp'. */
332 stp_unref(struct stp *stp)
334 if (stp && ovs_refcount_unref_relaxed(&stp->ref_cnt) == 1) {
337 ovs_mutex_lock(&mutex);
338 list_remove(&stp->node);
339 ovs_mutex_unlock(&mutex);
342 for (i = 0; i < STP_MAX_PORTS; i++) {
343 free(stp->ports[i].port_name);
349 /* Runs 'stp' given that 'ms' milliseconds have passed. */
351 stp_tick(struct stp *stp, int ms)
356 ovs_mutex_lock(&mutex);
357 /* Convert 'ms' to STP timer ticks. Preserve any leftover milliseconds
358 * from previous stp_tick() calls so that we don't lose STP ticks when we
359 * are called too frequently. */
360 ms = clamp(ms, 0, INT_MAX - 1000) + stp->elapsed_remainder;
361 elapsed = ms_to_timer(ms);
362 stp->elapsed_remainder = ms - timer_to_ms(elapsed);
367 if (stp_timer_expired(&stp->hello_timer, elapsed, stp->hello_time)) {
368 stp_hello_timer_expiry(stp);
370 if (stp_timer_expired(&stp->tcn_timer, elapsed, stp->bridge_hello_time)) {
371 stp_tcn_timer_expiry(stp);
373 if (stp_timer_expired(&stp->topology_change_timer, elapsed,
374 stp->max_age + stp->forward_delay)) {
375 stp_topology_change_timer_expiry(stp);
377 FOR_EACH_ENABLED_PORT (p, stp) {
378 if (stp_timer_expired(&p->message_age_timer, elapsed, stp->max_age)) {
379 stp_message_age_timer_expiry(p);
382 FOR_EACH_ENABLED_PORT (p, stp) {
383 if (stp_timer_expired(&p->forward_delay_timer, elapsed,
384 stp->forward_delay)) {
385 stp_forward_delay_timer_expiry(p);
387 if (stp_timer_expired(&p->hold_timer, elapsed, ms_to_timer(1000))) {
388 stp_hold_timer_expiry(p);
393 ovs_mutex_unlock(&mutex);
397 set_bridge_id(struct stp *stp, stp_identifier new_bridge_id)
400 if (new_bridge_id != stp->bridge_id) {
404 root = stp_is_root_bridge(stp);
405 FOR_EACH_ENABLED_PORT (p, stp) {
406 if (stp_is_designated_port(p)) {
407 p->designated_bridge = new_bridge_id;
410 stp->bridge_id = new_bridge_id;
411 stp_configuration_update(stp);
412 stp_port_state_selection(stp);
413 if (stp_is_root_bridge(stp) && !root) {
414 stp_become_root_bridge(stp);
420 stp_set_bridge_id(struct stp *stp, stp_identifier bridge_id)
422 const uint64_t mac_bits = (UINT64_C(1) << 48) - 1;
423 const uint64_t pri_bits = ~mac_bits;
424 ovs_mutex_lock(&mutex);
425 set_bridge_id(stp, (stp->bridge_id & pri_bits) | (bridge_id & mac_bits));
426 ovs_mutex_unlock(&mutex);
430 stp_set_bridge_priority(struct stp *stp, uint16_t new_priority)
432 const uint64_t mac_bits = (UINT64_C(1) << 48) - 1;
433 ovs_mutex_lock(&mutex);
434 set_bridge_id(stp, ((stp->bridge_id & mac_bits)
435 | ((uint64_t) new_priority << 48)));
436 ovs_mutex_unlock(&mutex);
439 /* Sets the desired hello time for 'stp' to 'ms', in milliseconds. The actual
440 * hello time is clamped to the range of 1 to 10 seconds and subject to the
441 * relationship (bridge_max_age >= 2 * (bridge_hello_time + 1 s)). The bridge
442 * hello time is only used when 'stp' is the root bridge. */
444 stp_set_hello_time(struct stp *stp, int ms)
446 ovs_mutex_lock(&mutex);
447 stp->rq_hello_time = ms;
448 stp_update_bridge_timers(stp);
449 ovs_mutex_unlock(&mutex);
452 /* Sets the desired max age for 'stp' to 'ms', in milliseconds. The actual max
453 * age is clamped to the range of 6 to 40 seconds and subject to the
454 * relationships (2 * (bridge_forward_delay - 1 s) >= bridge_max_age) and
455 * (bridge_max_age >= 2 * (bridge_hello_time + 1 s)). The bridge max age is
456 * only used when 'stp' is the root bridge. */
458 stp_set_max_age(struct stp *stp, int ms)
460 ovs_mutex_lock(&mutex);
461 stp->rq_max_age = ms;
462 stp_update_bridge_timers(stp);
463 ovs_mutex_unlock(&mutex);
466 /* Sets the desired forward delay for 'stp' to 'ms', in milliseconds. The
467 * actual forward delay is clamped to the range of 4 to 30 seconds and subject
468 * to the relationship (2 * (bridge_forward_delay - 1 s) >= bridge_max_age).
469 * The bridge forward delay is only used when 'stp' is the root bridge. */
471 stp_set_forward_delay(struct stp *stp, int ms)
473 ovs_mutex_lock(&mutex);
474 stp->rq_forward_delay = ms;
475 stp_update_bridge_timers(stp);
476 ovs_mutex_unlock(&mutex);
479 /* Returns the name given to 'stp' in the call to stp_create(). */
481 stp_get_name(const struct stp *stp)
485 ovs_mutex_lock(&mutex);
487 ovs_mutex_unlock(&mutex);
491 /* Returns the bridge ID for 'stp'. */
493 stp_get_bridge_id(const struct stp *stp)
495 stp_identifier bridge_id;
497 ovs_mutex_lock(&mutex);
498 bridge_id = stp->bridge_id;
499 ovs_mutex_unlock(&mutex);
503 /* Returns the bridge ID of the bridge currently believed to be the root. */
505 stp_get_designated_root(const struct stp *stp)
507 stp_identifier designated_root;
509 ovs_mutex_lock(&mutex);
510 designated_root = stp->designated_root;
511 ovs_mutex_unlock(&mutex);
512 return designated_root;
515 /* Returns true if 'stp' believes itself to the be root of the spanning tree,
516 * false otherwise. */
518 stp_is_root_bridge(const struct stp *stp)
522 ovs_mutex_lock(&mutex);
523 is_root = stp->bridge_id == stp->designated_root;
524 ovs_mutex_unlock(&mutex);
528 /* Returns the cost of the path from 'stp' to the root of the spanning tree. */
530 stp_get_root_path_cost(const struct stp *stp)
534 ovs_mutex_lock(&mutex);
535 cost = stp->root_path_cost;
536 ovs_mutex_unlock(&mutex);
540 /* Returns the bridge hello time, in ms. The returned value is not necessarily
541 * the value passed to stp_set_hello_time(): it is clamped to the valid range
542 * and quantized to the STP timer resolution. */
544 stp_get_hello_time(const struct stp *stp)
548 ovs_mutex_lock(&mutex);
549 time = timer_to_ms(stp->bridge_hello_time);
550 ovs_mutex_unlock(&mutex);
554 /* Returns the bridge max age, in ms. The returned value is not necessarily
555 * the value passed to stp_set_max_age(): it is clamped to the valid range,
556 * quantized to the STP timer resolution, and adjusted to match the constraints
557 * due to the hello time. */
559 stp_get_max_age(const struct stp *stp)
563 ovs_mutex_lock(&mutex);
564 time = timer_to_ms(stp->bridge_max_age);
565 ovs_mutex_unlock(&mutex);
569 /* Returns the bridge forward delay, in ms. The returned value is not
570 * necessarily the value passed to stp_set_forward_delay(): it is clamped to
571 * the valid range, quantized to the STP timer resolution, and adjusted to
572 * match the constraints due to the forward delay. */
574 stp_get_forward_delay(const struct stp *stp)
578 ovs_mutex_lock(&mutex);
579 time = timer_to_ms(stp->bridge_forward_delay);
580 ovs_mutex_unlock(&mutex);
584 /* Returns true if something has happened to 'stp' which necessitates flushing
585 * the client's MAC learning table. Calling this function resets 'stp' so that
586 * future calls will return false until flushing is required again. */
588 stp_check_and_reset_fdb_flush(struct stp *stp)
592 ovs_mutex_lock(&mutex);
593 needs_flush = stp->fdb_needs_flush;
594 stp->fdb_needs_flush = false;
595 ovs_mutex_unlock(&mutex);
599 /* Returns the port in 'stp' with index 'port_no', which must be between 0 and
602 stp_get_port(struct stp *stp, int port_no)
604 struct stp_port *port;
606 ovs_mutex_lock(&mutex);
607 ovs_assert(port_no >= 0 && port_no < ARRAY_SIZE(stp->ports));
608 port = &stp->ports[port_no];
609 ovs_mutex_unlock(&mutex);
613 /* Returns the port connecting 'stp' to the root bridge, or a null pointer if
614 * there is no such port. */
616 stp_get_root_port(struct stp *stp)
618 struct stp_port *port;
620 ovs_mutex_lock(&mutex);
621 port = stp->root_port;
622 ovs_mutex_unlock(&mutex);
626 /* Finds a port whose state has changed. If successful, stores the port whose
627 * state changed in '*portp' and returns true. If no port has changed, stores
628 * NULL in '*portp' and returns false. */
630 stp_get_changed_port(struct stp *stp, struct stp_port **portp)
632 struct stp_port *end, *p;
633 bool changed = false;
635 ovs_mutex_lock(&mutex);
636 end = &stp->ports[ARRAY_SIZE(stp->ports)];
637 for (p = stp->first_changed_port; p < end; p++) {
638 if (p->state_changed) {
639 p->state_changed = false;
640 stp->first_changed_port = p + 1;
646 stp->first_changed_port = end;
650 ovs_mutex_unlock(&mutex);
654 /* Returns the name for the given 'state' (for use in debugging and log
657 stp_state_name(enum stp_state state)
675 /* Returns true if 'state' is one in which packets received on a port should
676 * be forwarded, false otherwise.
679 stp_forward_in_state(enum stp_state state)
681 return (state & STP_FORWARDING) != 0;
684 /* Returns true if 'state' is one in which MAC learning should be done on
685 * packets received on a port, false otherwise.
688 stp_learn_in_state(enum stp_state state)
690 return (state & (STP_LEARNING | STP_FORWARDING)) != 0;
693 /* Returns true if 'state' is one in which bpdus should be forwarded on a
694 * port, false otherwise.
696 * Returns true if 'state' is STP_DISABLED, since in that case the port does
697 * not generate the bpdu and should just forward it (e.g. patch port on pif
700 stp_should_forward_bpdu(enum stp_state state)
703 ( STP_DISABLED | STP_LISTENING | STP_LEARNING
704 | STP_FORWARDING)) != 0;
707 /* Returns the name for the given 'role' (for use in debugging and log
710 stp_role_name(enum stp_role role)
715 case STP_ROLE_DESIGNATED:
717 case STP_ROLE_ALTERNATE:
719 case STP_ROLE_DISABLED:
726 /* Notifies the STP entity that bridge protocol data unit 'bpdu', which is
727 * 'bpdu_size' bytes in length, was received on port 'p'.
729 * This function may call the 'send_bpdu' function provided to stp_create(). */
731 stp_received_bpdu(struct stp_port *p, const void *bpdu, size_t bpdu_size)
733 struct stp *stp = p->stp;
734 const struct stp_bpdu_header *header;
736 ovs_mutex_lock(&mutex);
737 if (p->state == STP_DISABLED) {
741 if (bpdu_size < sizeof(struct stp_bpdu_header)) {
742 VLOG_WARN("%s: received runt %"PRIuSIZE"-byte BPDU", stp->name, bpdu_size);
748 if (header->protocol_id != htons(STP_PROTOCOL_ID)) {
749 VLOG_WARN("%s: received BPDU with unexpected protocol ID %"PRIu16,
750 stp->name, ntohs(header->protocol_id));
754 if (header->protocol_version != STP_PROTOCOL_VERSION) {
755 VLOG_DBG("%s: received BPDU with unexpected protocol version %"PRIu8,
756 stp->name, header->protocol_version);
759 switch (header->bpdu_type) {
760 case STP_TYPE_CONFIG:
761 if (bpdu_size < sizeof(struct stp_config_bpdu)) {
762 VLOG_WARN("%s: received config BPDU with invalid size %"PRIuSIZE,
763 stp->name, bpdu_size);
767 stp_received_config_bpdu(stp, p, bpdu);
771 if (bpdu_size != sizeof(struct stp_tcn_bpdu)) {
772 VLOG_WARN("%s: received TCN BPDU with invalid size %"PRIuSIZE,
773 stp->name, bpdu_size);
777 stp_received_tcn_bpdu(stp, p);
781 VLOG_WARN("%s: received BPDU of unexpected type %"PRIu8,
782 stp->name, header->bpdu_type);
789 ovs_mutex_unlock(&mutex);
792 /* Returns the STP entity in which 'p' is nested. */
794 stp_port_get_stp(struct stp_port *p)
798 ovs_mutex_lock(&mutex);
800 ovs_mutex_unlock(&mutex);
805 stp_port_set_name(struct stp_port *p, const char *name)
809 ovs_mutex_lock(&mutex);
811 p->port_name = xstrdup(name);
813 ovs_mutex_unlock(&mutex);
816 /* Sets the 'aux' member of 'p'.
818 * The 'aux' member will be reset to NULL when stp_port_disable() is
819 * called or stp_port_enable() is called when the port is in a Disabled
822 stp_port_set_aux(struct stp_port *p, void *aux)
824 ovs_mutex_lock(&mutex);
826 ovs_mutex_unlock(&mutex);
829 /* Returns the 'aux' member of 'p'. */
831 stp_port_get_aux(struct stp_port *p)
835 ovs_mutex_lock(&mutex);
837 ovs_mutex_unlock(&mutex);
841 /* Returns the index of port 'p' within its bridge. */
843 stp_port_no(const struct stp_port *p)
848 ovs_mutex_lock(&mutex);
850 ovs_assert(p >= stp->ports && p < &stp->ports[ARRAY_SIZE(stp->ports)]);
851 index = p - p->stp->ports;
852 ovs_mutex_unlock(&mutex);
856 /* Returns the port ID for 'p'. */
858 stp_port_get_id(const struct stp_port *p)
862 ovs_mutex_lock(&mutex);
863 port_id = p->port_id;
864 ovs_mutex_unlock(&mutex);
868 /* Returns the state of port 'p'. */
870 stp_port_get_state(const struct stp_port *p)
872 enum stp_state state;
874 ovs_mutex_lock(&mutex);
876 ovs_mutex_unlock(&mutex);
880 /* Returns the role of port 'p'. */
882 stp_port_get_role(const struct stp_port *p)
884 struct stp_port *root_port;
887 ovs_mutex_lock(&mutex);
888 root_port = p->stp->root_port;
889 if (root_port && root_port->port_id == p->port_id) {
890 role = STP_ROLE_ROOT;
891 } else if (stp_is_designated_port(p)) {
892 role = STP_ROLE_DESIGNATED;
893 } else if (p->state == STP_DISABLED) {
894 role = STP_ROLE_DISABLED;
896 role = STP_ROLE_ALTERNATE;
898 ovs_mutex_unlock(&mutex);
902 /* Retrieves BPDU transmit and receive counts for 'p'. */
904 stp_port_get_counts(const struct stp_port *p,
905 int *tx_count, int *rx_count, int *error_count)
907 ovs_mutex_lock(&mutex);
908 *tx_count = p->tx_count;
909 *rx_count = p->rx_count;
910 *error_count = p->error_count;
911 ovs_mutex_unlock(&mutex);
914 /* Disables STP on port 'p'. */
916 stp_port_disable(struct stp_port *p)
920 ovs_mutex_lock(&mutex);
922 if (p->state != STP_DISABLED) {
923 bool root = stp_is_root_bridge(stp);
924 stp_become_designated_port(p);
925 stp_set_port_state(p, STP_DISABLED);
926 p->topology_change_ack = false;
927 p->config_pending = false;
928 stp_stop_timer(&p->message_age_timer);
929 stp_stop_timer(&p->forward_delay_timer);
930 stp_configuration_update(stp);
931 stp_port_state_selection(stp);
932 if (stp_is_root_bridge(stp) && !root) {
933 stp_become_root_bridge(stp);
937 ovs_mutex_unlock(&mutex);
940 /* Enables STP on port 'p'. The port will initially be in "blocking" state. */
942 stp_port_enable(struct stp_port *p)
944 ovs_mutex_lock(&mutex);
945 if (p->state == STP_DISABLED) {
946 stp_initialize_port(p, STP_BLOCKING);
947 stp_port_state_selection(p->stp);
949 ovs_mutex_unlock(&mutex);
952 /* Sets the priority of port 'p' to 'new_priority'. Lower numerical values
953 * are interpreted as higher priorities. */
955 stp_port_set_priority(struct stp_port *p, uint8_t new_priority)
957 uint16_t new_port_id;
959 ovs_mutex_lock(&mutex);
960 new_port_id = (p->port_id & 0xff) | (new_priority << 8);
961 if (p->port_id != new_port_id) {
962 struct stp *stp = p->stp;
963 if (stp_is_designated_port(p)) {
964 p->designated_port = new_port_id;
966 p->port_id = new_port_id;
967 if (stp->bridge_id == p->designated_bridge
968 && p->port_id < p->designated_port) {
969 stp_become_designated_port(p);
970 stp_port_state_selection(stp);
973 ovs_mutex_unlock(&mutex);
976 /* Convert 'speed' (measured in Mb/s) into the path cost. */
978 stp_convert_speed_to_cost(unsigned int speed)
982 ovs_mutex_lock(&mutex);
983 ret = speed >= 10000 ? 2 /* 10 Gb/s. */
984 : speed >= 1000 ? 4 /* 1 Gb/s. */
985 : speed >= 100 ? 19 /* 100 Mb/s. */
986 : speed >= 16 ? 62 /* 16 Mb/s. */
987 : speed >= 10 ? 100 /* 10 Mb/s. */
988 : speed >= 4 ? 250 /* 4 Mb/s. */
989 : 19; /* 100 Mb/s (guess). */
990 ovs_mutex_unlock(&mutex);
994 /* Sets the path cost of port 'p' to 'path_cost'. Lower values are generally
995 * used to indicate faster links. Use stp_port_set_speed() to automatically
996 * generate a default path cost from a link speed. */
998 stp_port_set_path_cost(struct stp_port *p, uint16_t path_cost)
1000 ovs_mutex_lock(&mutex);
1001 if (p->path_cost != path_cost) {
1002 struct stp *stp = p->stp;
1003 p->path_cost = path_cost;
1004 stp_configuration_update(stp);
1005 stp_port_state_selection(stp);
1007 ovs_mutex_unlock(&mutex);
1010 /* Sets the path cost of port 'p' based on 'speed' (measured in Mb/s). */
1012 stp_port_set_speed(struct stp_port *p, unsigned int speed)
1014 stp_port_set_path_cost(p, stp_convert_speed_to_cost(speed));
1017 /* Enables topology change detection on port 'p'. */
1019 stp_port_enable_change_detection(struct stp_port *p)
1021 p->change_detection_enabled = true;
1024 /* Disables topology change detection on port 'p'. */
1026 stp_port_disable_change_detection(struct stp_port *p)
1028 p->change_detection_enabled = false;
1032 stp_transmit_config(struct stp_port *p) OVS_REQUIRES(mutex)
1034 struct stp *stp = p->stp;
1035 bool root = stp_is_root_bridge(stp);
1036 if (!root && !stp->root_port) {
1039 if (p->hold_timer.active) {
1040 VLOG_DBG_RL(&stp_rl, "bridge: %s, port: %s, transmit config bpdu pending",
1041 stp->name, p->port_name);
1042 p->config_pending = true;
1044 struct stp_config_bpdu config;
1045 memset(&config, 0, sizeof config);
1046 config.header.protocol_id = htons(STP_PROTOCOL_ID);
1047 config.header.protocol_version = STP_PROTOCOL_VERSION;
1048 config.header.bpdu_type = STP_TYPE_CONFIG;
1050 if (p->topology_change_ack) {
1051 config.flags |= STP_CONFIG_TOPOLOGY_CHANGE_ACK;
1053 if (stp->topology_change) {
1054 config.flags |= STP_CONFIG_TOPOLOGY_CHANGE;
1056 config.root_id = htonll(stp->designated_root);
1057 config.root_path_cost = htonl(stp->root_path_cost);
1058 config.bridge_id = htonll(stp->bridge_id);
1059 config.port_id = htons(p->port_id);
1061 config.message_age = htons(0);
1063 config.message_age = htons(stp->root_port->message_age_timer.value
1064 + MESSAGE_AGE_INCREMENT);
1066 config.max_age = htons(stp->max_age);
1067 config.hello_time = htons(stp->hello_time);
1068 config.forward_delay = htons(stp->forward_delay);
1069 if (ntohs(config.message_age) < stp->max_age) {
1070 p->topology_change_ack = false;
1071 p->config_pending = false;
1072 VLOG_DBG_RL(&stp_rl, "bridge: %s, port: %s, transmit config bpdu",
1073 stp->name, p->port_name);
1074 stp_send_bpdu(p, &config, sizeof config);
1075 stp_start_timer(&p->hold_timer, 0);
1081 stp_supersedes_port_info(const struct stp_port *p,
1082 const struct stp_config_bpdu *config)
1085 if (ntohll(config->root_id) != p->designated_root) {
1086 return ntohll(config->root_id) < p->designated_root;
1087 } else if (ntohl(config->root_path_cost) != p->designated_cost) {
1088 return ntohl(config->root_path_cost) < p->designated_cost;
1089 } else if (ntohll(config->bridge_id) != p->designated_bridge) {
1090 return ntohll(config->bridge_id) < p->designated_bridge;
1092 return (ntohll(config->bridge_id) != p->stp->bridge_id
1093 || ntohs(config->port_id) <= p->designated_port);
1098 stp_record_config_information(struct stp_port *p,
1099 const struct stp_config_bpdu *config)
1102 p->designated_root = ntohll(config->root_id);
1103 p->designated_cost = ntohl(config->root_path_cost);
1104 p->designated_bridge = ntohll(config->bridge_id);
1105 p->designated_port = ntohs(config->port_id);
1106 stp_start_timer(&p->message_age_timer, ntohs(config->message_age));
1110 stp_record_config_timeout_values(struct stp *stp,
1111 const struct stp_config_bpdu *config)
1114 stp->max_age = ntohs(config->max_age);
1115 stp->hello_time = ntohs(config->hello_time);
1116 stp->forward_delay = ntohs(config->forward_delay);
1117 stp->topology_change = config->flags & STP_CONFIG_TOPOLOGY_CHANGE;
1121 stp_is_designated_port(const struct stp_port *p) OVS_REQUIRES(mutex)
1123 return (p->designated_bridge == p->stp->bridge_id
1124 && p->designated_port == p->port_id);
1128 stp_config_bpdu_generation(struct stp *stp) OVS_REQUIRES(mutex)
1132 FOR_EACH_ENABLED_PORT (p, stp) {
1133 if (stp_is_designated_port(p)) {
1134 stp_transmit_config(p);
1140 stp_transmit_tcn(struct stp *stp) OVS_REQUIRES(mutex)
1142 struct stp_port *p = stp->root_port;
1143 struct stp_tcn_bpdu tcn_bpdu;
1148 VLOG_DBG_RL(&stp_rl, "bridge: %s, root port: %s, transmit tcn", stp->name,
1150 tcn_bpdu.header.protocol_id = htons(STP_PROTOCOL_ID);
1151 tcn_bpdu.header.protocol_version = STP_PROTOCOL_VERSION;
1152 tcn_bpdu.header.bpdu_type = STP_TYPE_TCN;
1153 stp_send_bpdu(p, &tcn_bpdu, sizeof tcn_bpdu);
1157 stp_configuration_update(struct stp *stp) OVS_REQUIRES(mutex)
1159 stp_root_selection(stp);
1160 stp_designated_port_selection(stp);
1161 seq_change(connectivity_seq_get());
1165 stp_supersedes_root(const struct stp_port *root, const struct stp_port *p)
1168 int p_cost = p->designated_cost + p->path_cost;
1169 int root_cost = root->designated_cost + root->path_cost;
1171 if (p->designated_root != root->designated_root) {
1172 return p->designated_root < root->designated_root;
1173 } else if (p_cost != root_cost) {
1174 return p_cost < root_cost;
1175 } else if (p->designated_bridge != root->designated_bridge) {
1176 return p->designated_bridge < root->designated_bridge;
1177 } else if (p->designated_port != root->designated_port) {
1178 return p->designated_port < root->designated_port;
1180 return p->port_id < root->port_id;
1185 stp_root_selection(struct stp *stp) OVS_REQUIRES(mutex)
1187 struct stp_port *p, *root;
1190 FOR_EACH_ENABLED_PORT (p, stp) {
1191 if (stp_is_designated_port(p)
1192 || p->designated_root >= stp->bridge_id) {
1195 if (root && !stp_supersedes_root(root, p)) {
1200 stp->root_port = root;
1202 stp->designated_root = stp->bridge_id;
1203 stp->root_path_cost = 0;
1205 stp->designated_root = root->designated_root;
1206 stp->root_path_cost = root->designated_cost + root->path_cost;
1211 stp_designated_port_selection(struct stp *stp) OVS_REQUIRES(mutex)
1215 FOR_EACH_ENABLED_PORT (p, stp) {
1216 if (stp_is_designated_port(p)
1217 || p->designated_root != stp->designated_root
1218 || stp->root_path_cost < p->designated_cost
1219 || (stp->root_path_cost == p->designated_cost
1220 && (stp->bridge_id < p->designated_bridge
1221 || (stp->bridge_id == p->designated_bridge
1222 && p->port_id <= p->designated_port))))
1224 stp_become_designated_port(p);
1230 stp_become_designated_port(struct stp_port *p) OVS_REQUIRES(mutex)
1232 struct stp *stp = p->stp;
1233 p->designated_root = stp->designated_root;
1234 p->designated_cost = stp->root_path_cost;
1235 p->designated_bridge = stp->bridge_id;
1236 p->designated_port = p->port_id;
1240 stp_port_state_selection(struct stp *stp) OVS_REQUIRES(mutex)
1244 FOR_EACH_ENABLED_PORT (p, stp) {
1245 if (p == stp->root_port) {
1246 p->config_pending = false;
1247 p->topology_change_ack = false;
1248 stp_make_forwarding(p);
1249 } else if (stp_is_designated_port(p)) {
1250 stp_stop_timer(&p->message_age_timer);
1251 stp_make_forwarding(p);
1253 p->config_pending = false;
1254 p->topology_change_ack = false;
1255 stp_make_blocking(p);
1261 stp_make_forwarding(struct stp_port *p) OVS_REQUIRES(mutex)
1263 if (p->state == STP_BLOCKING) {
1264 stp_set_port_state(p, STP_LISTENING);
1265 stp_start_timer(&p->forward_delay_timer, 0);
1270 stp_make_blocking(struct stp_port *p) OVS_REQUIRES(mutex)
1272 if (!(p->state & (STP_DISABLED | STP_BLOCKING))) {
1273 if (p->state & (STP_FORWARDING | STP_LEARNING)) {
1274 if (p->change_detection_enabled) {
1275 stp_topology_change_detection(p->stp);
1278 stp_set_port_state(p, STP_BLOCKING);
1279 stp_stop_timer(&p->forward_delay_timer);
1284 stp_set_port_state(struct stp_port *p, enum stp_state state)
1287 if (state != p->state && !p->state_changed) {
1288 p->state_changed = true;
1289 if (p < p->stp->first_changed_port) {
1290 p->stp->first_changed_port = p;
1292 seq_change(connectivity_seq_get());
1298 stp_topology_change_detection(struct stp *stp) OVS_REQUIRES(mutex)
1300 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
1302 if (stp_is_root_bridge(stp)) {
1303 stp->topology_change = true;
1304 stp_start_timer(&stp->topology_change_timer, 0);
1305 } else if (!stp->topology_change_detected) {
1306 stp_transmit_tcn(stp);
1307 stp_start_timer(&stp->tcn_timer, 0);
1309 stp->fdb_needs_flush = true;
1310 stp->topology_change_detected = true;
1311 seq_change(connectivity_seq_get());
1312 VLOG_INFO_RL(&rl, "%s: detected topology change.", stp->name);
1316 stp_topology_change_acknowledged(struct stp *stp) OVS_REQUIRES(mutex)
1318 stp->topology_change_detected = false;
1319 stp_stop_timer(&stp->tcn_timer);
1323 stp_acknowledge_topology_change(struct stp_port *p) OVS_REQUIRES(mutex)
1325 p->topology_change_ack = true;
1326 stp_transmit_config(p);
1330 stp_received_config_bpdu(struct stp *stp, struct stp_port *p,
1331 const struct stp_config_bpdu *config)
1334 if (ntohs(config->message_age) >= ntohs(config->max_age)) {
1335 VLOG_WARN("%s: received config BPDU with message age (%u) greater "
1336 "than max age (%u)",
1338 ntohs(config->message_age), ntohs(config->max_age));
1341 if (p->state != STP_DISABLED) {
1342 bool root = stp_is_root_bridge(stp);
1343 if (stp_supersedes_port_info(p, config)) {
1344 stp_record_config_information(p, config);
1345 stp_configuration_update(stp);
1346 stp_port_state_selection(stp);
1347 if (!stp_is_root_bridge(stp) && root) {
1348 stp_stop_timer(&stp->hello_timer);
1349 if (stp->topology_change_detected) {
1350 stp_stop_timer(&stp->topology_change_timer);
1351 stp_transmit_tcn(stp);
1352 stp_start_timer(&stp->tcn_timer, 0);
1355 if (p == stp->root_port) {
1356 stp_record_config_timeout_values(stp, config);
1357 stp_config_bpdu_generation(stp);
1358 if (config->flags & STP_CONFIG_TOPOLOGY_CHANGE_ACK) {
1359 stp_topology_change_acknowledged(stp);
1361 if (config->flags & STP_CONFIG_TOPOLOGY_CHANGE) {
1362 stp->fdb_needs_flush = true;
1365 } else if (stp_is_designated_port(p)) {
1366 stp_transmit_config(p);
1372 stp_received_tcn_bpdu(struct stp *stp, struct stp_port *p)
1375 if (p->state != STP_DISABLED) {
1376 if (stp_is_designated_port(p)) {
1377 stp_topology_change_detection(stp);
1378 stp_acknowledge_topology_change(p);
1384 stp_hello_timer_expiry(struct stp *stp) OVS_REQUIRES(mutex)
1386 stp_config_bpdu_generation(stp);
1387 stp_start_timer(&stp->hello_timer, 0);
1391 stp_message_age_timer_expiry(struct stp_port *p) OVS_REQUIRES(mutex)
1393 struct stp *stp = p->stp;
1394 bool root = stp_is_root_bridge(stp);
1396 VLOG_DBG_RL(&stp_rl, "bridge: %s, port: %s, message age timer expired",
1397 stp->name, p->port_name);
1398 stp_become_designated_port(p);
1399 stp_configuration_update(stp);
1400 stp_port_state_selection(stp);
1401 if (stp_is_root_bridge(stp) && !root) {
1402 stp->max_age = stp->bridge_max_age;
1403 stp->hello_time = stp->bridge_hello_time;
1404 stp->forward_delay = stp->bridge_forward_delay;
1405 stp_topology_change_detection(stp);
1406 stp_stop_timer(&stp->tcn_timer);
1407 stp_config_bpdu_generation(stp);
1408 stp_start_timer(&stp->hello_timer, 0);
1413 stp_is_designated_for_some_port(const struct stp *stp) OVS_REQUIRES(mutex)
1415 const struct stp_port *p;
1417 FOR_EACH_ENABLED_PORT (p, stp) {
1418 if (p->designated_bridge == stp->bridge_id) {
1426 stp_forward_delay_timer_expiry(struct stp_port *p) OVS_REQUIRES(mutex)
1428 if (p->state == STP_LISTENING) {
1429 stp_set_port_state(p, STP_LEARNING);
1430 stp_start_timer(&p->forward_delay_timer, 0);
1431 } else if (p->state == STP_LEARNING) {
1432 stp_set_port_state(p, STP_FORWARDING);
1433 if (stp_is_designated_for_some_port(p->stp)) {
1434 if (p->change_detection_enabled) {
1435 stp_topology_change_detection(p->stp);
1442 stp_tcn_timer_expiry(struct stp *stp) OVS_REQUIRES(mutex)
1444 stp_transmit_tcn(stp);
1445 stp_start_timer(&stp->tcn_timer, 0);
1449 stp_topology_change_timer_expiry(struct stp *stp) OVS_REQUIRES(mutex)
1451 stp->topology_change_detected = false;
1452 stp->topology_change = false;
1456 stp_hold_timer_expiry(struct stp_port *p) OVS_REQUIRES(mutex)
1458 if (p->config_pending) {
1459 stp_transmit_config(p);
1464 stp_initialize_port(struct stp_port *p, enum stp_state state)
1467 ovs_assert(state & (STP_DISABLED | STP_BLOCKING));
1468 stp_become_designated_port(p);
1470 if (!p->state && state == STP_DISABLED) {
1471 p->state = state; /* Do not trigger state change when initializing. */
1473 stp_set_port_state(p, state);
1475 p->topology_change_ack = false;
1476 p->config_pending = false;
1477 p->change_detection_enabled = true;
1479 stp_stop_timer(&p->message_age_timer);
1480 stp_stop_timer(&p->forward_delay_timer);
1481 stp_stop_timer(&p->hold_timer);
1482 p->tx_count = p->rx_count = p->error_count = 0;
1486 stp_become_root_bridge(struct stp *stp) OVS_REQUIRES(mutex)
1488 stp->max_age = stp->bridge_max_age;
1489 stp->hello_time = stp->bridge_hello_time;
1490 stp->forward_delay = stp->bridge_forward_delay;
1491 stp_topology_change_detection(stp);
1492 stp_stop_timer(&stp->tcn_timer);
1493 stp_config_bpdu_generation(stp);
1494 stp_start_timer(&stp->hello_timer, 0);
1498 stp_start_timer(struct stp_timer *timer, int value) OVS_REQUIRES(mutex)
1500 timer->value = value;
1501 timer->active = true;
1505 stp_stop_timer(struct stp_timer *timer) OVS_REQUIRES(mutex)
1507 timer->active = false;
1511 stp_timer_expired(struct stp_timer *timer, int elapsed, int timeout)
1514 if (timer->active) {
1515 timer->value += elapsed;
1516 if (timer->value >= timeout) {
1517 timer->active = false;
1524 /* Returns the number of whole STP timer ticks in 'ms' milliseconds. There
1525 * are 256 STP timer ticks per second. */
1529 return ms * 0x100 / 1000;
1532 /* Returns the number of whole milliseconds in 'timer' STP timer ticks. There
1533 * are 256 STP timer ticks per second. */
1535 timer_to_ms(int timer)
1537 return timer * 1000 / 0x100;
1541 clamp(int x, int min, int max)
1543 return x < min ? min : x > max ? max : x;
1547 stp_update_bridge_timers(struct stp *stp) OVS_REQUIRES(mutex)
1551 ht = clamp(stp->rq_hello_time, 1000, 10000);
1552 ma = clamp(stp->rq_max_age, MAX(2 * (ht + 1000), 6000), 40000);
1553 fd = clamp(stp->rq_forward_delay, ma / 2 + 1000, 30000);
1555 stp->bridge_hello_time = ms_to_timer(ht);
1556 stp->bridge_max_age = ms_to_timer(ma);
1557 stp->bridge_forward_delay = ms_to_timer(fd);
1559 if (stp_is_root_bridge(stp)) {
1560 stp->max_age = stp->bridge_max_age;
1561 stp->hello_time = stp->bridge_hello_time;
1562 stp->forward_delay = stp->bridge_forward_delay;
1567 stp_send_bpdu(struct stp_port *p, const void *bpdu, size_t bpdu_size)
1570 struct eth_header *eth;
1571 struct llc_header *llc;
1575 pkt = ofpbuf_new(ETH_HEADER_LEN + LLC_HEADER_LEN + bpdu_size);
1576 eth = ofpbuf_put_zeros(pkt, sizeof *eth);
1577 llc = ofpbuf_put_zeros(pkt, sizeof *llc);
1578 ofpbuf_set_frame(pkt, eth);
1579 ofpbuf_set_l3(pkt, ofpbuf_put(pkt, bpdu, bpdu_size));
1582 memcpy(eth->eth_dst, eth_addr_stp, ETH_ADDR_LEN);
1583 /* p->stp->send_bpdu() must fill in source address. */
1584 eth->eth_type = htons(ofpbuf_size(pkt) - ETH_HEADER_LEN);
1587 llc->llc_dsap = STP_LLC_DSAP;
1588 llc->llc_ssap = STP_LLC_SSAP;
1589 llc->llc_cntl = STP_LLC_CNTL;
1591 p->stp->send_bpdu(pkt, stp_port_no(p), p->stp->aux);
1598 stp_find(const char *name) OVS_REQUIRES(mutex)
1602 LIST_FOR_EACH (stp, node, all_stps) {
1603 if (!strcmp(stp->name, name)) {
1611 stp_unixctl_tcn(struct unixctl_conn *conn, int argc,
1612 const char *argv[], void *aux OVS_UNUSED)
1614 ovs_mutex_lock(&mutex);
1616 struct stp *stp = stp_find(argv[1]);
1619 unixctl_command_reply_error(conn, "no such stp object");
1622 stp_topology_change_detection(stp);
1626 LIST_FOR_EACH (stp, node, all_stps) {
1627 stp_topology_change_detection(stp);
1631 unixctl_command_reply(conn, "OK");
1634 ovs_mutex_unlock(&mutex);