lib/rstp.c

   1 /*
   2  * Copyright (c) 2011-2014 M3S, Srl - Italy
   3  *
   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:
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  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.
  15  */
  16
  17 /*
  18  * Rapid Spanning Tree Protocol (IEEE 802.1D-2004) public interface.
  19  *
  20  * Authors:
  21  *         Martino Fornasa <mf@fornasa.it>
  22  *         Daniele Venturino <daniele.venturino@m3s.it>
  23  *
  24  * References to IEEE 802.1D-2004 standard are enclosed in square brackets.
  25  * E.g. [17.3], [Table 17-1], etc.
  26  *
  27  */
  28
  29 #include <config.h>
  30
  31 #include "rstp.h"
  32 #include "rstp-common.h"
  33 #include "rstp-state-machines.h"
  34 #include <arpa/inet.h>
  35 #include <inttypes.h>
  36 #include <netinet/in.h>
  37 #include <stdlib.h>
  38 #include <sys/types.h>
  39 #include "byte-order.h"
  40 #include "connectivity.h"
  41 #include "ofpbuf.h"
  42 #include "ofproto/ofproto.h"
  43 #include "packets.h"
  44 #include "seq.h"
  45 #include "unixctl.h"
  46 #include "util.h"
  47 #include "vlog.h"
  48
  49 VLOG_DEFINE_THIS_MODULE(rstp);
  50
  51 struct ovs_mutex rstp_mutex = OVS_MUTEX_INITIALIZER;
  52
  53 static struct list all_rstps__ = LIST_INITIALIZER(&all_rstps__);
  54 static struct list *const all_rstps OVS_GUARDED_BY(rstp_mutex) = &all_rstps__;
  55
  56 /* Internal use only. */
  57 static void rstp_set_bridge_address__(struct rstp *, rstp_identifier)
  58     OVS_REQUIRES(rstp_mutex);
  59 static void rstp_set_bridge_priority__(struct rstp *, int new_priority)
  60     OVS_REQUIRES(rstp_mutex);
  61 static void rstp_set_bridge_ageing_time__(struct rstp *, int new_ageing_time)
  62     OVS_REQUIRES(rstp_mutex);
  63 static void rstp_set_bridge_force_protocol_version__(struct rstp *,
  64                                                      enum rstp_force_protocol_version)
  65     OVS_REQUIRES(rstp_mutex);
  66 static void rstp_set_bridge_hello_time__(struct rstp *)
  67     OVS_REQUIRES(rstp_mutex);
  68 static void rstp_set_bridge_max_age__(struct rstp *, int new_max_age)
  69     OVS_REQUIRES(rstp_mutex);
  70 static void rstp_set_bridge_forward_delay__(struct rstp *, int new_forward_delay)
  71     OVS_REQUIRES(rstp_mutex);
  72 static void rstp_set_bridge_transmit_hold_count__(struct rstp *,
  73                                                   int new_transmit_hold_count)
  74     OVS_REQUIRES(rstp_mutex);
  75 static void rstp_set_bridge_migrate_time__(struct rstp *)
  76     OVS_REQUIRES(rstp_mutex);
  77 static void rstp_set_bridge_times__(struct rstp *, int new_forward_delay,
  78                                     int new_hello_time, int new_max_age,
  79                                     int new_message_age)
  80     OVS_REQUIRES(rstp_mutex);
  81
  82 static struct rstp_port *rstp_get_port__(struct rstp *rstp,
  83                                          uint16_t port_number)
  84     OVS_REQUIRES(rstp_mutex);
  85 static void set_port_id__(struct rstp_port *)
  86     OVS_REQUIRES(rstp_mutex);
  87 static void update_port_enabled__(struct rstp_port *)
  88     OVS_REQUIRES(rstp_mutex);
  89 static void set_bridge_priority__(struct rstp *)
  90     OVS_REQUIRES(rstp_mutex);
  91 static void reinitialize_rstp__(struct rstp *)
  92     OVS_REQUIRES(rstp_mutex);
  93 static bool is_port_number_available__(struct rstp *, int, struct rstp_port *)
  94     OVS_REQUIRES(rstp_mutex);
  95 static uint16_t rstp_first_free_number__(struct rstp *, struct rstp_port *)
  96     OVS_REQUIRES(rstp_mutex);
  97 static void rstp_initialize_port_defaults__(struct rstp_port *)
  98     OVS_REQUIRES(rstp_mutex);
  99 static void rstp_port_set_priority__(struct rstp_port *, int priority)
 100     OVS_REQUIRES(rstp_mutex);
 101 static void rstp_port_set_port_number__(struct rstp_port *,
 102                                         uint16_t port_number)
 103     OVS_REQUIRES(rstp_mutex);
 104 static void rstp_port_set_path_cost__(struct rstp_port *, uint32_t path_cost)
 105     OVS_REQUIRES(rstp_mutex);
 106 static void rstp_port_set_administrative_bridge_port__(struct rstp_port *,
 107                                                        uint8_t admin_port_state,
 108                                                        bool initializing)
 109     OVS_REQUIRES(rstp_mutex);
 110 static void rstp_port_set_admin_edge__(struct rstp_port *, bool admin_edge)
 111     OVS_REQUIRES(rstp_mutex);
 112 static void rstp_port_set_auto_edge__(struct rstp_port *, bool auto_edge)
 113     OVS_REQUIRES(rstp_mutex);
 114 static void rstp_port_set_admin_point_to_point_mac__(struct rstp_port *,
 115         enum rstp_admin_point_to_point_mac_state admin_p2p_mac_state)
 116     OVS_REQUIRES(rstp_mutex);
 117 static void rstp_port_set_mcheck__(struct rstp_port *, bool mcheck)
 118     OVS_REQUIRES(rstp_mutex);
 119 static void reinitialize_port__(struct rstp_port *p)
 120     OVS_REQUIRES(rstp_mutex);
 121
 122 const char *
 123 rstp_state_name(enum rstp_state state)
 124 {
 125     switch (state) {
 126     case RSTP_DISABLED:
 127         return "Disabled";
 128     case RSTP_LEARNING:
 129         return "Learning";
 130     case RSTP_FORWARDING:
 131         return "Forwarding";
 132     case RSTP_DISCARDING:
 133         return "Discarding";
 134     default:
 135         return "Unknown";
 136     }
 137 }
 138
 139 const char *
 140 rstp_port_role_name(enum rstp_port_role role)
 141 {
 142     switch (role) {
 143     case ROLE_ROOT:
 144         return "Root";
 145     case ROLE_DESIGNATED:
 146         return "Designated";
 147     case ROLE_ALTERNATE:
 148         return "Alternate";
 149     case ROLE_BACKUP:
 150         return "Backup";
 151     case ROLE_DISABLED:
 152         return "Disabled";
 153     default:
 154         return "Unknown";
 155     }
 156 }
 157
 158 /* Caller has to hold a reference to prevent 'rstp' from being deleted
 159  * while taking a new reference. */
 160 struct rstp *
 161 rstp_ref(struct rstp *rstp)
 162     OVS_EXCLUDED(rstp_mutex)
 163 {
 164     if (rstp) {
 165         ovs_refcount_ref(&rstp->ref_cnt);
 166     }
 167     return rstp;
 168 }
 169
 170 /* Frees RSTP struct when reference count reaches zero. */
 171 void
 172 rstp_unref(struct rstp *rstp)
 173     OVS_EXCLUDED(rstp_mutex)
 174 {
 175     if (rstp && ovs_refcount_unref_relaxed(&rstp->ref_cnt) == 1) {
 176         ovs_mutex_lock(&rstp_mutex);
 177
 178         /* Each RSTP port points back to struct rstp without holding a
 179          * reference for that pointer.  This is OK as we never move
 180          * ports from one bridge to another, and holders always
 181          * release their ports before releasing the bridge.  This
 182          * means that there should be not ports at this time. */
 183         ovs_assert(hmap_is_empty(&rstp->ports));
 184
 185         list_remove(&rstp->node);
 186         ovs_mutex_unlock(&rstp_mutex);
 187         free(rstp->name);
 188         free(rstp);
 189     }
 190 }
 191
 192 /* Returns the port number.  Mutex is needed to guard against
 193  * concurrent reinitialization (which can temporarily clear the
 194  * port_number). */
 195 int
 196 rstp_port_get_number(const struct rstp_port *p)
 197     OVS_EXCLUDED(rstp_mutex)
 198 {
 199     int number;
 200
 201     ovs_mutex_lock(&rstp_mutex);
 202     number = p->port_number;
 203     ovs_mutex_unlock(&rstp_mutex);
 204
 205     return number;
 206 }
 207
 208 static void rstp_unixctl_tcn(struct unixctl_conn *, int argc,
 209                              const char *argv[], void *aux);
 210
 211 /* Decrements the State Machines' timers. */
 212 void
 213 rstp_tick_timers(struct rstp *rstp)
 214     OVS_EXCLUDED(rstp_mutex)
 215 {
 216     ovs_mutex_lock(&rstp_mutex);
 217     decrease_rstp_port_timers__(rstp);
 218     ovs_mutex_unlock(&rstp_mutex);
 219 }
 220
 221 /* Processes an incoming BPDU. */
 222 void
 223 rstp_port_received_bpdu(struct rstp_port *rp, const void *bpdu,
 224                         size_t bpdu_size)
 225     OVS_EXCLUDED(rstp_mutex)
 226 {
 227     ovs_mutex_lock(&rstp_mutex);
 228     /* Only process packets on ports that have RSTP enabled. */
 229     if (rp && rp->rstp_state != RSTP_DISABLED) {
 230         process_received_bpdu__(rp, bpdu, bpdu_size);
 231     }
 232     ovs_mutex_unlock(&rstp_mutex);
 233 }
 234
 235 void
 236 rstp_init(void)
 237     OVS_EXCLUDED(rstp_mutex)
 238 {
 239     unixctl_command_register("rstp/tcn", "[bridge]", 0, 1, rstp_unixctl_tcn,
 240                              NULL);
 241 }
 242
 243 /* Creates and returns a new RSTP instance that initially has no ports. */
 244 struct rstp *
 245 rstp_create(const char *name, rstp_identifier bridge_address,
 246             void (*send_bpdu)(struct ofpbuf *bpdu, void *port_aux,
 247                               void *rstp_aux),
 248             void *aux)
 249     OVS_EXCLUDED(rstp_mutex)
 250 {
 251     struct rstp *rstp;
 252
 253     VLOG_DBG("Creating RSTP instance");
 254
 255     rstp = xzalloc(sizeof *rstp);
 256     rstp->name = xstrdup(name);
 257
 258     /* Initialize the ports map before calling any setters,
 259      * so that the state machines will see an empty ports map. */
 260     hmap_init(&rstp->ports);
 261
 262     ovs_mutex_lock(&rstp_mutex);
 263     /* Set bridge address. */
 264     rstp_set_bridge_address__(rstp, bridge_address);
 265     /* Set default parameters values. */
 266     rstp_set_bridge_priority__(rstp, RSTP_DEFAULT_PRIORITY);
 267     rstp_set_bridge_ageing_time__(rstp, RSTP_DEFAULT_AGEING_TIME);
 268     rstp_set_bridge_force_protocol_version__(rstp, FPV_DEFAULT);
 269     rstp_set_bridge_forward_delay__(rstp, RSTP_DEFAULT_BRIDGE_FORWARD_DELAY);
 270     rstp_set_bridge_hello_time__(rstp);
 271     rstp_set_bridge_max_age__(rstp, RSTP_DEFAULT_BRIDGE_MAX_AGE);
 272     rstp_set_bridge_migrate_time__(rstp);
 273     rstp_set_bridge_transmit_hold_count__(rstp,
 274                                           RSTP_DEFAULT_TRANSMIT_HOLD_COUNT);
 275     rstp_set_bridge_times__(rstp, RSTP_DEFAULT_BRIDGE_FORWARD_DELAY,
 276                             RSTP_BRIDGE_HELLO_TIME,
 277                             RSTP_DEFAULT_BRIDGE_MAX_AGE, 0);
 278     rstp->send_bpdu = send_bpdu;
 279     rstp->aux = aux;
 280     rstp->changes = false;
 281     rstp->begin = true;
 282
 283     ovs_refcount_init(&rstp->ref_cnt);
 284
 285     list_push_back(all_rstps, &rstp->node);
 286     ovs_mutex_unlock(&rstp_mutex);
 287
 288     VLOG_DBG("RSTP instance creation done");
 289     return rstp;
 290 }
 291
 292 /* Called by rstp_set_bridge_address() and rstp_set_bridge_priority(),
 293  * it updates the bridge priority vector according to the values passed by
 294  * those setters.
 295  */
 296 static void
 297 set_bridge_priority__(struct rstp *rstp)
 298     OVS_REQUIRES(rstp_mutex)
 299 {
 300     struct rstp_port *p;
 301
 302     rstp->bridge_priority.root_bridge_id = rstp->bridge_identifier;
 303     rstp->bridge_priority.designated_bridge_id = rstp->bridge_identifier;
 304     VLOG_DBG("%s: new bridge identifier: "RSTP_ID_FMT"", rstp->name,
 305              RSTP_ID_ARGS(rstp->bridge_identifier));
 306
 307     /* [17.13] When the bridge address changes, recalculates all priority
 308      * vectors.
 309      */
 310     HMAP_FOR_EACH (p, node, &rstp->ports) {
 311         p->selected = false;
 312         p->reselect = true;
 313     }
 314     rstp->changes = true;
 315     updt_roles_tree__(rstp);
 316 }
 317
 318 /* Sets the bridge address. */
 319 static void
 320 rstp_set_bridge_address__(struct rstp *rstp, rstp_identifier bridge_address)
 321     OVS_REQUIRES(rstp_mutex)
 322 {
 323     VLOG_DBG("%s: set bridge address to: "RSTP_ID_FMT"", rstp->name,
 324              RSTP_ID_ARGS(bridge_address));
 325
 326     rstp->address = bridge_address;
 327     rstp->bridge_identifier = bridge_address;
 328     set_bridge_priority__(rstp);
 329 }
 330
 331 /* Sets the bridge address. */
 332 void
 333 rstp_set_bridge_address(struct rstp *rstp, rstp_identifier bridge_address)
 334     OVS_EXCLUDED(rstp_mutex)
 335 {
 336     ovs_mutex_lock(&rstp_mutex);
 337     rstp_set_bridge_address__(rstp, bridge_address);
 338     ovs_mutex_unlock(&rstp_mutex);
 339 }
 340
 341 const char *
 342 rstp_get_name(const struct rstp *rstp)
 343     OVS_EXCLUDED(rstp_mutex)
 344 {
 345     char *name;
 346
 347     ovs_mutex_lock(&rstp_mutex);
 348     name = rstp->name;
 349     ovs_mutex_unlock(&rstp_mutex);
 350     return name;
 351 }
 352
 353 rstp_identifier
 354 rstp_get_bridge_id(const struct rstp *rstp)
 355     OVS_EXCLUDED(rstp_mutex)
 356 {
 357     rstp_identifier bridge_id;
 358
 359     ovs_mutex_lock(&rstp_mutex);
 360     bridge_id = rstp->bridge_identifier;
 361     ovs_mutex_unlock(&rstp_mutex);
 362
 363     return bridge_id;
 364 }
 365
 366 /* Sets the bridge priority. */
 367 static void
 368 rstp_set_bridge_priority__(struct rstp *rstp, int new_priority)
 369     OVS_REQUIRES(rstp_mutex)
 370 {
 371     new_priority = ROUND_DOWN(new_priority, RSTP_PRIORITY_STEP);
 372
 373     if (new_priority >= RSTP_MIN_PRIORITY
 374         && new_priority <= RSTP_MAX_PRIORITY) {
 375         VLOG_DBG("%s: set bridge priority to %d", rstp->name, new_priority);
 376
 377         rstp->priority = new_priority;
 378         rstp->bridge_identifier &= 0x0000ffffffffffffULL;
 379         rstp->bridge_identifier |= (uint64_t)new_priority << 48;
 380         set_bridge_priority__(rstp);
 381     }
 382 }
 383
 384 void
 385 rstp_set_bridge_priority(struct rstp *rstp, int new_priority)
 386     OVS_EXCLUDED(rstp_mutex)
 387 {
 388     ovs_mutex_lock(&rstp_mutex);
 389     rstp_set_bridge_priority__(rstp, new_priority);
 390     ovs_mutex_unlock(&rstp_mutex);
 391 }
 392
 393 /* Sets the bridge ageing time. */
 394 static void
 395 rstp_set_bridge_ageing_time__(struct rstp *rstp, int new_ageing_time)
 396     OVS_REQUIRES(rstp_mutex)
 397 {
 398     if (new_ageing_time >= RSTP_MIN_AGEING_TIME
 399         && new_ageing_time <= RSTP_MAX_AGEING_TIME) {
 400         VLOG_DBG("%s: set ageing time to %d", rstp->name, new_ageing_time);
 401
 402         rstp->ageing_time = new_ageing_time;
 403     }
 404 }
 405
 406 void
 407 rstp_set_bridge_ageing_time(struct rstp *rstp, int new_ageing_time)
 408     OVS_EXCLUDED(rstp_mutex)
 409 {
 410     ovs_mutex_lock(&rstp_mutex);
 411     rstp_set_bridge_ageing_time__(rstp, new_ageing_time);
 412     ovs_mutex_unlock(&rstp_mutex);
 413 }
 414
 415 /* Reinitializes RSTP when switching from RSTP mode to STP mode
 416  * or vice versa.
 417  */
 418 static void
 419 reinitialize_rstp__(struct rstp *rstp)
 420     OVS_REQUIRES(rstp_mutex)
 421 {
 422     struct rstp temp;
 423     static struct hmap ports;
 424     struct rstp_port *p;
 425
 426     /* Copy rstp in temp */
 427     temp = *rstp;
 428     ports = rstp->ports;
 429
 430     /* stop and clear rstp */
 431     memset(rstp, 0, sizeof(struct rstp));
 432
 433     /* Initialize rstp. */
 434     rstp->name = temp.name;
 435
 436     /* Initialize the ports hmap before calling any setters,
 437      * so that the state machines will see an empty ports list. */
 438     hmap_init(&rstp->ports);
 439
 440     /* Set bridge address. */
 441     rstp_set_bridge_address__(rstp, temp.address);
 442     /* Set default parameters values. */
 443     rstp_set_bridge_priority__(rstp, RSTP_DEFAULT_PRIORITY);
 444     rstp_set_bridge_ageing_time__(rstp, RSTP_DEFAULT_AGEING_TIME);
 445     rstp_set_bridge_forward_delay__(rstp, RSTP_DEFAULT_BRIDGE_FORWARD_DELAY);
 446     rstp_set_bridge_hello_time__(rstp);
 447     rstp_set_bridge_max_age__(rstp, RSTP_DEFAULT_BRIDGE_MAX_AGE);
 448     rstp_set_bridge_migrate_time__(rstp);
 449     rstp_set_bridge_transmit_hold_count__(rstp,
 450                                           RSTP_DEFAULT_TRANSMIT_HOLD_COUNT);
 451     rstp_set_bridge_times__(rstp, RSTP_DEFAULT_BRIDGE_FORWARD_DELAY,
 452                             RSTP_BRIDGE_HELLO_TIME,
 453                             RSTP_DEFAULT_BRIDGE_MAX_AGE, 0);
 454
 455     rstp->send_bpdu = temp.send_bpdu;
 456     rstp->aux = temp.aux;
 457     rstp->node = temp.node;
 458     rstp->changes = false;
 459     rstp->begin = true;
 460
 461     /* Restore ports. */
 462     rstp->ports = ports;
 463
 464     HMAP_FOR_EACH (p, node, &rstp->ports) {
 465         reinitialize_port__(p);
 466     }
 467
 468     rstp->ref_cnt = temp.ref_cnt;
 469 }
 470
 471 /* Sets the force protocol version parameter. */
 472 static void
 473 rstp_set_bridge_force_protocol_version__(struct rstp *rstp,
 474                 enum rstp_force_protocol_version new_force_protocol_version)
 475     OVS_REQUIRES(rstp_mutex)
 476 {
 477     if (new_force_protocol_version != rstp->force_protocol_version &&
 478             (new_force_protocol_version == FPV_STP_COMPATIBILITY ||
 479              new_force_protocol_version == FPV_DEFAULT)) {
 480         VLOG_DBG("%s: set bridge Force Protocol Version to %d", rstp->name,
 481                  new_force_protocol_version);
 482
 483         /* [17.13] The Spanning Tree Protocol Entity shall be reinitialized,
 484          * as specified by the assertion of BEGIN (17.18.1) in the state
 485          * machine specification.
 486          */
 487         reinitialize_rstp__(rstp);
 488         rstp->force_protocol_version = new_force_protocol_version;
 489         if (rstp->force_protocol_version < 2) {
 490             rstp->stp_version = true;
 491             rstp->rstp_version = false;
 492         } else {
 493             rstp->stp_version = false;
 494             rstp->rstp_version = true;
 495         }
 496         rstp->changes = true;
 497         move_rstp__(rstp);
 498     }
 499 }
 500
 501 void
 502 rstp_set_bridge_force_protocol_version(struct rstp *rstp,
 503                 enum rstp_force_protocol_version new_force_protocol_version)
 504     OVS_EXCLUDED(rstp_mutex)
 505 {
 506     ovs_mutex_lock(&rstp_mutex);
 507     rstp_set_bridge_force_protocol_version__(rstp, new_force_protocol_version);
 508     ovs_mutex_unlock(&rstp_mutex);
 509 }
 510
 511 /* Sets the bridge Hello Time parameter. */
 512 static void
 513 rstp_set_bridge_hello_time__(struct rstp *rstp)
 514     OVS_REQUIRES(rstp_mutex)
 515 {
 516     VLOG_DBG("%s: set RSTP Hello Time to %d", rstp->name,
 517              RSTP_BRIDGE_HELLO_TIME);
 518     /* 2 is the only acceptable value. */
 519     rstp->bridge_hello_time = RSTP_BRIDGE_HELLO_TIME;
 520 }
 521
 522 /* Sets the bridge max age parameter. */
 523 static void
 524 rstp_set_bridge_max_age__(struct rstp *rstp, int new_max_age)
 525     OVS_REQUIRES(rstp_mutex)
 526 {
 527     if (rstp->bridge_max_age != new_max_age
 528         && new_max_age >= RSTP_MIN_BRIDGE_MAX_AGE
 529         && new_max_age <= RSTP_MAX_BRIDGE_MAX_AGE) {
 530         /* [17.13] */
 531         if ((2 * (rstp->bridge_forward_delay - 1) >= new_max_age)
 532             && (new_max_age >= 2 * rstp->bridge_hello_time)) {
 533             VLOG_DBG("%s: set RSTP bridge Max Age to %d", rstp->name,
 534                      new_max_age);
 535
 536             rstp->bridge_max_age = new_max_age;
 537             rstp->bridge_times.max_age = new_max_age;
 538             rstp->changes = true;
 539             updt_roles_tree__(rstp);
 540         }
 541     }
 542 }
 543
 544 void
 545 rstp_set_bridge_max_age(struct rstp *rstp, int new_max_age)
 546     OVS_EXCLUDED(rstp_mutex)
 547 {
 548     ovs_mutex_lock(&rstp_mutex);
 549     rstp_set_bridge_max_age__(rstp, new_max_age);
 550     ovs_mutex_unlock(&rstp_mutex);
 551 }
 552
 553 /* Sets the bridge forward delay parameter. */
 554 static void
 555 rstp_set_bridge_forward_delay__(struct rstp *rstp, int new_forward_delay)
 556     OVS_REQUIRES(rstp_mutex)
 557 {
 558     if (rstp->bridge_forward_delay != new_forward_delay
 559             && new_forward_delay >= RSTP_MIN_BRIDGE_FORWARD_DELAY
 560             && new_forward_delay <= RSTP_MAX_BRIDGE_FORWARD_DELAY) {
 561         if (2 * (new_forward_delay - 1) >= rstp->bridge_max_age) {
 562             VLOG_DBG("%s: set RSTP Forward Delay to %d", rstp->name,
 563                      new_forward_delay);
 564             rstp->bridge_forward_delay = new_forward_delay;
 565             rstp->bridge_times.forward_delay = new_forward_delay;
 566             rstp->changes = true;
 567             updt_roles_tree__(rstp);
 568         }
 569     }
 570 }
 571
 572 void
 573 rstp_set_bridge_forward_delay(struct rstp *rstp, int new_forward_delay)
 574     OVS_EXCLUDED(rstp_mutex)
 575 {
 576     ovs_mutex_lock(&rstp_mutex);
 577     rstp_set_bridge_forward_delay__(rstp, new_forward_delay);
 578     ovs_mutex_unlock(&rstp_mutex);
 579 }
 580
 581 /* Sets the bridge transmit hold count parameter. */
 582 static void
 583 rstp_set_bridge_transmit_hold_count__(struct rstp *rstp,
 584                                       int new_transmit_hold_count)
 585     OVS_REQUIRES(rstp_mutex)
 586 {
 587     if (new_transmit_hold_count >= RSTP_MIN_TRANSMIT_HOLD_COUNT
 588         && new_transmit_hold_count <= RSTP_MAX_TRANSMIT_HOLD_COUNT) {
 589         struct rstp_port *p;
 590
 591         VLOG_DBG("%s: set RSTP Transmit Hold Count to %d", rstp->name,
 592                  new_transmit_hold_count);
 593         /* Resetting txCount on all ports [17.13]. */
 594
 595         rstp->transmit_hold_count = new_transmit_hold_count;
 596         HMAP_FOR_EACH (p, node, &rstp->ports) {
 597             p->tx_count = 0;
 598         }
 599     }
 600 }
 601
 602 void
 603 rstp_set_bridge_transmit_hold_count(struct rstp *rstp,
 604                                     int new_transmit_hold_count)
 605     OVS_EXCLUDED(rstp_mutex)
 606 {
 607     ovs_mutex_lock(&rstp_mutex);
 608     rstp_set_bridge_transmit_hold_count__(rstp, new_transmit_hold_count);
 609     ovs_mutex_unlock(&rstp_mutex);
 610 }
 611
 612 /* Sets the bridge migrate time parameter. */
 613 static void
 614 rstp_set_bridge_migrate_time__(struct rstp *rstp)
 615     OVS_REQUIRES(rstp_mutex)
 616 {
 617     VLOG_DBG("%s: set RSTP Migrate Time to %d", rstp->name,
 618              RSTP_MIGRATE_TIME);
 619     /* 3 is the only acceptable value */
 620     rstp->migrate_time = RSTP_MIGRATE_TIME;
 621 }
 622
 623 /* Sets the bridge times. */
 624 static void
 625 rstp_set_bridge_times__(struct rstp *rstp, int new_forward_delay,
 626                         int new_hello_time, int new_max_age,
 627                         int new_message_age)
 628     OVS_REQUIRES(rstp_mutex)
 629 {
 630     VLOG_DBG("%s: set RSTP times to (%d, %d, %d, %d)", rstp->name,
 631              new_forward_delay, new_hello_time, new_max_age, new_message_age);
 632     if (new_forward_delay >= RSTP_MIN_BRIDGE_FORWARD_DELAY
 633         && new_forward_delay <= RSTP_MAX_BRIDGE_FORWARD_DELAY) {
 634         rstp->bridge_times.forward_delay = new_forward_delay;
 635     }
 636     if (new_hello_time == RSTP_BRIDGE_HELLO_TIME) {
 637         rstp->bridge_times.hello_time = new_hello_time;
 638     }
 639     if (new_max_age >= RSTP_MIN_BRIDGE_MAX_AGE
 640         && new_max_age <= RSTP_MAX_BRIDGE_MAX_AGE) {
 641         rstp->bridge_times.max_age = new_max_age;
 642     }
 643     rstp->bridge_times.message_age = new_message_age;
 644 }
 645
 646 /* Sets the port id, it is called by rstp_port_set_port_number__() or
 647  * rstp_port_set_priority__().
 648  */
 649 static void
 650 set_port_id__(struct rstp_port *p)
 651     OVS_REQUIRES(rstp_mutex)
 652 {
 653     struct rstp *rstp;
 654
 655     rstp = p->rstp;
 656     /* [9.2.7] Port identifier. */
 657     p->port_id = p->port_number | (p->priority << 8);
 658     VLOG_DBG("%s: new RSTP port id "RSTP_PORT_ID_FMT"", rstp->name,
 659              p->port_id);
 660 }
 661
 662 /* Sets the port priority. */
 663 static void
 664 rstp_port_set_priority__(struct rstp_port *port, int priority)
 665     OVS_REQUIRES(rstp_mutex)
 666 {
 667     if (priority >= RSTP_MIN_PORT_PRIORITY
 668         && priority <= RSTP_MAX_PORT_PRIORITY) {
 669         VLOG_DBG("%s, port %u: set RSTP port priority to %d", port->rstp->name,
 670                  port->port_number, priority);
 671
 672         priority -= priority % RSTP_STEP_PORT_PRIORITY;
 673         port->priority = priority;
 674         set_port_id__(port);
 675         port->selected = false;
 676         port->reselect = true;
 677     }
 678 }
 679
 680 /* Checks if a port number is available. */
 681 static bool
 682 is_port_number_available__(struct rstp *rstp, int n, struct rstp_port *port)
 683     OVS_REQUIRES(rstp_mutex)
 684 {
 685     if (n >= 1 && n <= RSTP_MAX_PORTS) {
 686         struct rstp_port *p = rstp_get_port__(rstp, n);
 687
 688         return p == NULL || p == port;
 689     }
 690     return false;
 691 }
 692
 693 static uint16_t
 694 rstp_first_free_number__(struct rstp *rstp, struct rstp_port *rstp_port)
 695     OVS_REQUIRES(rstp_mutex)
 696 {
 697     int free_number = 1;
 698
 699     while (free_number <= RSTP_MAX_PORTS) {
 700         if (is_port_number_available__(rstp, free_number, rstp_port)) {
 701             return free_number;
 702         }
 703         free_number++;
 704     }
 705     VLOG_DBG("%s, No free port number available.", rstp->name);
 706     return 0;
 707 }
 708
 709 /* Sets the port number. */
 710 static void
 711 rstp_port_set_port_number__(struct rstp_port *port, uint16_t port_number)
 712     OVS_REQUIRES(rstp_mutex)
 713 {
 714     /* If new_port_number is available, use it, otherwise use the first free
 715      * available port number. */
 716     port->port_number =
 717         is_port_number_available__(port->rstp, port_number, port)
 718         ? port_number
 719         : rstp_first_free_number__(port->rstp, port);
 720
 721     set_port_id__(port);
 722     /* [17.13] is not clear. I suppose that a port number change
 723      * should trigger reselection like a port priority change. */
 724     port->selected = false;
 725     port->reselect = true;
 726
 727     VLOG_DBG("%s: set new RSTP port number %d", port->rstp->name,
 728              port->port_number);
 729 }
 730
 731 /* Converts the link speed to a port path cost [Table 17-3]. */
 732 uint32_t
 733 rstp_convert_speed_to_cost(unsigned int speed)
 734 {
 735     uint32_t value;
 736
 737     value = speed >= 10000000 ? 2 /* 10 Tb/s. */
 738           : speed >= 1000000 ? 20 /* 1 Tb/s. */
 739           : speed >= 100000 ? 200 /* 100 Gb/s. */
 740           : speed >= 10000 ? 2000 /* 10 Gb/s. */
 741           : speed >= 1000 ? 20000 /* 1 Gb/s. */
 742           : speed >= 100 ? 200000 /* 100 Mb/s. */
 743           : speed >= 10 ? 2000000 /* 10 Mb/s. */
 744           : speed >= 1 ? 20000000 /* 1 Mb/s. */
 745           : RSTP_DEFAULT_PORT_PATH_COST; /* 100 Mb/s. */
 746
 747     return value;
 748 }
 749
 750 /* Sets the port path cost. */
 751 static void
 752 rstp_port_set_path_cost__(struct rstp_port *port, uint32_t path_cost)
 753     OVS_REQUIRES(rstp_mutex)
 754 {
 755     if (path_cost >= RSTP_MIN_PORT_PATH_COST
 756         && path_cost <= RSTP_MAX_PORT_PATH_COST) {
 757         VLOG_DBG("%s, port %u, set RSTP port path cost to %d",
 758                  port->rstp->name, port->port_number, path_cost);
 759
 760         port->port_path_cost = path_cost;
 761         port->selected = false;
 762         port->reselect = true;
 763     }
 764 }
 765
 766 /* Gets the root path cost. */
 767 uint32_t
 768 rstp_get_root_path_cost(const struct rstp *rstp)
 769     OVS_EXCLUDED(rstp_mutex)
 770 {
 771     uint32_t cost;
 772
 773     ovs_mutex_lock(&rstp_mutex);
 774     cost = rstp->root_priority.root_path_cost;
 775     ovs_mutex_unlock(&rstp_mutex);
 776     return cost;
 777 }
 778
 779 /* Finds a port which needs to flush its own MAC learning table.  A NULL
 780  * pointer is returned if no port needs to flush its MAC learning table.
 781  * '*port' needs to be NULL in the first call to start the iteration.  If
 782  * '*port' is passed as non-NULL, it must be the value set by the last
 783  * invocation of this function. */
 784 void *
 785 rstp_check_and_reset_fdb_flush(struct rstp *rstp, struct rstp_port **port)
 786     OVS_EXCLUDED(rstp_mutex)
 787 {
 788     void *aux = NULL;
 789
 790     ovs_mutex_lock(&rstp_mutex);
 791     if (*port == NULL) {
 792         struct rstp_port *p;
 793
 794         HMAP_FOR_EACH (p, node, &rstp->ports) {
 795             if (p->fdb_flush) {
 796                 aux = p->aux;
 797                 *port = p;
 798                 goto out;
 799             }
 800         }
 801     } else { /* continue */
 802         struct rstp_port *p = *port;
 803
 804         HMAP_FOR_EACH_CONTINUE (p, node, &rstp->ports) {
 805             if (p->fdb_flush) {
 806                 aux = p->aux;
 807                 *port = p;
 808                 goto out;
 809             }
 810         }
 811     }
 812     /* No port needs flushing. */
 813     *port = NULL;
 814 out:
 815     /* fdb_flush should be reset by the filtering database
 816      * once the entries are removed if rstp_version is TRUE, and
 817      * immediately if stp_version is TRUE.*/
 818     if (*port != NULL) {
 819         (*port)->fdb_flush = false;
 820     }
 821     ovs_mutex_unlock(&rstp_mutex);
 822     return aux;
 823     }
 824
 825 /* Finds a port whose state has changed, and returns the aux pointer set for
 826  * the port.  A NULL pointer is returned when no changed port is found.  On
 827  * return '*portp' contains the pointer to the rstp port that changed, or NULL
 828  * if no changed port can be found.
 829  *
 830  * If '*portp' is passed as non-NULL, it must be the value set by the last
 831  * invocation of this function.
 832  *
 833  * This function may only be called by the thread that creates and deletes
 834  * ports.  Otherwise this function is not thread safe, as the returned
 835  * '*portp' could become stale before it is used in the next invocation. */
 836 void *
 837 rstp_get_next_changed_port_aux(struct rstp *rstp, struct rstp_port **portp)
 838 {
 839     void *aux = NULL;
 840
 841     ovs_mutex_lock(&rstp_mutex);
 842     if (*portp == NULL) {
 843         struct rstp_port *p;
 844
 845         HMAP_FOR_EACH (p, node, &rstp->ports) {
 846             if (p->state_changed) {
 847                 p->state_changed = false;
 848                 aux = p->aux;
 849                 *portp = p;
 850                 goto out;
 851             }
 852         }
 853     } else { /* continue */
 854         struct rstp_port *p = *portp;
 855
 856         HMAP_FOR_EACH_CONTINUE (p, node, &rstp->ports) {
 857             if (p->state_changed) {
 858                 p->state_changed = false;
 859                 aux = p->aux;
 860                 *portp = p;
 861                 goto out;
 862             }
 863         }
 864     }
 865     /* No changed port found. */
 866     *portp = NULL;
 867 out:
 868     ovs_mutex_unlock(&rstp_mutex);
 869     return aux;
 870 }
 871
 872 /* Returns the port in 'rstp' with number 'port_number'.
 873  *
 874  * XXX: May only be called while concurrent deletion of ports is excluded. */
 875 static struct rstp_port *
 876 rstp_get_port__(struct rstp *rstp, uint16_t port_number)
 877     OVS_REQUIRES(rstp_mutex)
 878 {
 879     struct rstp_port *port;
 880
 881     ovs_assert(rstp && port_number > 0 && port_number <= RSTP_MAX_PORTS);
 882
 883     HMAP_FOR_EACH_WITH_HASH (port, node, hash_int(port_number, 0),
 884                              &rstp->ports) {
 885         if (port->port_number == port_number) {
 886             return port;
 887         }
 888     }
 889     return NULL;
 890 }
 891
 892 struct rstp_port *
 893 rstp_get_port(struct rstp *rstp, uint16_t port_number)
 894     OVS_EXCLUDED(rstp_mutex)
 895 {
 896     struct rstp_port *p;
 897
 898     ovs_mutex_lock(&rstp_mutex);
 899     p = rstp_get_port__(rstp, port_number);
 900     ovs_mutex_unlock(&rstp_mutex);
 901     return p;
 902 }
 903
 904 void *
 905 rstp_get_port_aux(struct rstp *rstp, uint16_t port_number)
 906     OVS_EXCLUDED(rstp_mutex)
 907 {
 908     struct rstp_port *p;
 909     void *aux;
 910
 911     ovs_mutex_lock(&rstp_mutex);
 912     p = rstp_get_port__(rstp, port_number);
 913     aux = p->aux;
 914     ovs_mutex_unlock(&rstp_mutex);
 915     return aux;
 916 }
 917
 918 /* Updates the port_enabled parameter. */
 919 static void
 920 update_port_enabled__(struct rstp_port *p)
 921     OVS_REQUIRES(rstp_mutex)
 922 {
 923     if (p->mac_operational && p->is_administrative_bridge_port
 924         == RSTP_ADMIN_BRIDGE_PORT_STATE_ENABLED) {
 925         p->port_enabled = true;
 926     } else {
 927         p->port_enabled = false;
 928     }
 929 }
 930
 931 /* Sets the port MAC_Operational parameter [6.4.2]. */
 932 void
 933 rstp_port_set_mac_operational(struct rstp_port *p, bool new_mac_operational)
 934     OVS_EXCLUDED(rstp_mutex)
 935 {
 936     struct rstp *rstp;
 937
 938     ovs_mutex_lock(&rstp_mutex);
 939     rstp = p->rstp;
 940     if (p->mac_operational != new_mac_operational) {
 941         p->mac_operational = new_mac_operational;
 942         update_port_enabled__(p);
 943         rstp->changes = true;
 944         move_rstp__(rstp);
 945     }
 946     ovs_mutex_unlock(&rstp_mutex);
 947 }
 948
 949 /* Sets the port Administrative Bridge Port parameter. */
 950 static void
 951 rstp_port_set_administrative_bridge_port__(struct rstp_port *p,
 952                                            uint8_t admin_port_state,
 953                                            bool initializing)
 954     OVS_REQUIRES(rstp_mutex)
 955 {
 956     VLOG_DBG("%s, port %u: set RSTP port admin-port-state to %d",
 957              p->rstp->name, p->port_number, admin_port_state);
 958
 959     if (admin_port_state == RSTP_ADMIN_BRIDGE_PORT_STATE_DISABLED
 960         || admin_port_state == RSTP_ADMIN_BRIDGE_PORT_STATE_ENABLED) {
 961
 962         p->is_administrative_bridge_port = admin_port_state;
 963         update_port_enabled__(p);
 964
 965         if (!initializing) {
 966             struct rstp *rstp = p->rstp;
 967
 968             rstp->changes = true;
 969             move_rstp__(rstp);
 970         }
 971     }
 972 }
 973
 974 /* Sets the port oper_point_to_point_mac parameter. */
 975 static void
 976 rstp_port_set_oper_point_to_point_mac__(struct rstp_port *p,
 977                                         uint8_t new_oper_p2p_mac)
 978     OVS_REQUIRES(rstp_mutex)
 979 {
 980     if (new_oper_p2p_mac == RSTP_OPER_P2P_MAC_STATE_DISABLED
 981         || new_oper_p2p_mac == RSTP_OPER_P2P_MAC_STATE_ENABLED) {
 982
 983         p->oper_point_to_point_mac = new_oper_p2p_mac;
 984         update_port_enabled__(p);
 985     }
 986 }
 987
 988 /* Initializes a port with the defaults values for its parameters. */
 989 static void
 990 rstp_initialize_port_defaults__(struct rstp_port *p)
 991     OVS_REQUIRES(rstp_mutex)
 992 {
 993     rstp_port_set_administrative_bridge_port__(p,
 994                                                RSTP_ADMIN_BRIDGE_PORT_STATE_ENABLED,
 995                                                true);
 996     rstp_port_set_oper_point_to_point_mac__(p,
 997                                          RSTP_OPER_P2P_MAC_STATE_ENABLED);
 998     rstp_port_set_path_cost__(p, RSTP_DEFAULT_PORT_PATH_COST);
 999     rstp_port_set_admin_edge__(p, false);
1000     rstp_port_set_auto_edge__(p, true);
1001     rstp_port_set_mcheck__(p, false);
1002
1003     /* Initialize state machines. */
1004     p->port_receive_sm_state = PORT_RECEIVE_SM_INIT;
1005     p->port_protocol_migration_sm_state = PORT_PROTOCOL_MIGRATION_SM_INIT;
1006     p->bridge_detection_sm_state = BRIDGE_DETECTION_SM_INIT;
1007     p->port_transmit_sm_state = PORT_TRANSMIT_SM_INIT;
1008     p->port_information_sm_state = PORT_INFORMATION_SM_INIT;
1009     p->port_role_transition_sm_state = PORT_ROLE_TRANSITION_SM_INIT;
1010     p->port_state_transition_sm_state = PORT_STATE_TRANSITION_SM_INIT;
1011     p->topology_change_sm_state = TOPOLOGY_CHANGE_SM_INIT;
1012     p->uptime = 0;
1013
1014 }
1015
1016 static void
1017 reinitialize_port__(struct rstp_port *p)
1018     OVS_REQUIRES(rstp_mutex)
1019 {
1020     struct rstp_port temp_port;
1021     struct rstp *rstp;
1022
1023     rstp = p->rstp;
1024     temp_port = *p;
1025     memset(p, 0, sizeof(struct rstp_port));
1026
1027     p->ref_cnt = temp_port.ref_cnt;
1028     p->rstp = rstp;
1029     p->node = temp_port.node;
1030     p->aux = temp_port.aux;
1031     p->port_number = temp_port.port_number;
1032     p->port_priority = temp_port.port_priority;
1033     p->port_id = temp_port.port_id;
1034     p->rstp_state = RSTP_DISCARDING;
1035
1036     rstp_initialize_port_defaults__(p);
1037
1038     VLOG_DBG("%s: RSTP port "RSTP_PORT_ID_FMT" reinitialized.", rstp->name,
1039              p->port_id);
1040 }
1041
1042 void
1043 reinitialize_port(struct rstp_port *p)
1044     OVS_EXCLUDED(rstp_mutex)
1045 {
1046     ovs_mutex_lock(&rstp_mutex);
1047     reinitialize_port__(p);
1048     ovs_mutex_unlock(&rstp_mutex);
1049 }
1050
1051 /* Sets the port state. */
1052 void
1053 rstp_port_set_state__(struct rstp_port *p, enum rstp_state state)
1054     OVS_REQUIRES(rstp_mutex)
1055 {
1056     struct rstp *rstp;
1057
1058     rstp = p->rstp;
1059     VLOG_DBG("%s, port %u: set RSTP port state %s -> %s", rstp->name,
1060              p->port_number,
1061              rstp_state_name(p->rstp_state), rstp_state_name(state));
1062
1063     if (state != p->rstp_state && !p->state_changed) {
1064         p->state_changed = true;
1065         seq_change(connectivity_seq_get());
1066     }
1067     p->rstp_state = state;
1068 }
1069
1070 void
1071 rstp_port_set_state(struct rstp_port *p, enum rstp_state state)
1072     OVS_EXCLUDED(rstp_mutex)
1073 {
1074     ovs_mutex_lock(&rstp_mutex);
1075     rstp_port_set_state__(p, state);
1076     ovs_mutex_unlock(&rstp_mutex);
1077 }
1078
1079 /* Adds a RSTP port. */
1080 struct rstp_port *
1081 rstp_add_port(struct rstp *rstp)
1082     OVS_EXCLUDED(rstp_mutex)
1083 {
1084     struct rstp_port *p = xzalloc(sizeof *p);
1085
1086     ovs_refcount_init(&p->ref_cnt);
1087
1088     ovs_mutex_lock(&rstp_mutex);
1089     p->rstp = rstp;
1090     rstp_port_set_priority__(p, RSTP_DEFAULT_PORT_PRIORITY);
1091     rstp_port_set_port_number__(p, 0);
1092     p->aux = NULL;
1093     rstp_initialize_port_defaults__(p);
1094     VLOG_DBG("%s: RSTP port "RSTP_PORT_ID_FMT" initialized.", rstp->name,
1095              p->port_id);
1096
1097     rstp_port_set_state__(p, RSTP_DISCARDING);
1098     hmap_insert(&rstp->ports, &p->node, hash_int(p->port_number, 0));
1099     rstp->changes = true;
1100     move_rstp__(rstp);
1101     VLOG_DBG("%s: added port "RSTP_PORT_ID_FMT"", rstp->name, p->port_id);
1102     ovs_mutex_unlock(&rstp_mutex);
1103     return p;
1104 }
1105
1106 /* Caller has to hold a reference to prevent 'rstp_port' from being deleted
1107  * while taking a new reference. */
1108 struct rstp_port *
1109 rstp_port_ref(const struct rstp_port *rp_)
1110     OVS_EXCLUDED(rstp_mutex)
1111 {
1112     struct rstp_port *rp = CONST_CAST(struct rstp_port *, rp_);
1113
1114     if (rp) {
1115         ovs_refcount_ref(&rp->ref_cnt);
1116     }
1117     return rp;
1118 }
1119
1120 /* Frees RSTP struct.  This can be caller by any thread. */
1121 void
1122 rstp_port_unref(struct rstp_port *rp)
1123     OVS_EXCLUDED(rstp_mutex)
1124 {
1125     if (rp && ovs_refcount_unref_relaxed(&rp->ref_cnt) == 1) {
1126         struct rstp *rstp;
1127
1128         ovs_mutex_lock(&rstp_mutex);
1129         rstp = rp->rstp;
1130         rstp_port_set_state__(rp, RSTP_DISABLED);
1131         hmap_remove(&rstp->ports, &rp->node);
1132         VLOG_DBG("%s: removed port "RSTP_PORT_ID_FMT"", rstp->name,
1133                  rp->port_id);
1134         ovs_mutex_unlock(&rstp_mutex);
1135         free(rp);
1136     }
1137 }
1138
1139 /* Sets the port Admin Edge parameter. */
1140 static void
1141 rstp_port_set_admin_edge__(struct rstp_port *port, bool admin_edge)
1142      OVS_REQUIRES(rstp_mutex)
1143 {
1144     if (port->admin_edge != admin_edge) {
1145         VLOG_DBG("%s, port %u: set RSTP Admin Edge to %d", port->rstp->name,
1146                  port->port_number, admin_edge);
1147
1148         port->admin_edge = admin_edge;
1149     }
1150 }
1151
1152 /* Sets the port Auto Edge parameter. */
1153 static void
1154 rstp_port_set_auto_edge__(struct rstp_port *port, bool auto_edge)
1155     OVS_REQUIRES(rstp_mutex)
1156 {
1157     if (port->auto_edge != auto_edge) {
1158         VLOG_DBG("%s, port %u: set RSTP Auto Edge to %d", port->rstp->name,
1159                  port->port_number, auto_edge);
1160
1161         port->auto_edge = auto_edge;
1162     }
1163 }
1164
1165 /* Sets the port admin_point_to_point_mac parameter. */
1166 static void rstp_port_set_admin_point_to_point_mac__(struct rstp_port *port,
1167         enum rstp_admin_point_to_point_mac_state admin_p2p_mac_state)
1168     OVS_REQUIRES(rstp_mutex)
1169 {
1170     VLOG_DBG("%s, port %u: set RSTP port admin-point-to-point-mac to %d",
1171             port->rstp->name, port->port_number, admin_p2p_mac_state);
1172
1173     if (admin_p2p_mac_state == RSTP_ADMIN_P2P_MAC_FORCE_TRUE) {
1174         port->admin_point_to_point_mac = admin_p2p_mac_state;
1175         rstp_port_set_oper_point_to_point_mac__(port,
1176                 RSTP_OPER_P2P_MAC_STATE_ENABLED);
1177     } else if (admin_p2p_mac_state == RSTP_ADMIN_P2P_MAC_FORCE_FALSE) {
1178         port->admin_point_to_point_mac = admin_p2p_mac_state;
1179         rstp_port_set_oper_point_to_point_mac__(port,
1180                 RSTP_OPER_P2P_MAC_STATE_DISABLED);
1181     } else if (admin_p2p_mac_state == RSTP_ADMIN_P2P_MAC_AUTO) {
1182         /* If adminPointToPointMAC is set to Auto, then the value of
1183          * operPointToPointMAC is determined in accordance with the
1184          * specific procedures defined for the MAC entity concerned, as
1185          * defined in 6.5. If these procedures determine that the MAC
1186          * entity is connected to a point-to-point LAN, then
1187          * operPointToPointMAC is set TRUE; otherwise it is set FALSE.
1188          * In the absence of a specific definition of how to determine
1189          * whether the MAC is connected to a point-to-point LAN or not,
1190          * the value of operPointToPointMAC shall be FALSE. */
1191         port->admin_point_to_point_mac = admin_p2p_mac_state;
1192         rstp_port_set_oper_point_to_point_mac__(
1193             port, RSTP_OPER_P2P_MAC_STATE_DISABLED);
1194     }
1195 }
1196
1197 /* Sets the port mcheck parameter.
1198  * [17.19.13] May be set by management to force the Port Protocol Migration
1199  * state machine to transmit RST BPDUs for a MigrateTime (17.13.9) period, to
1200  * test whether all STP Bridges (17.4) on the attached LAN have been removed
1201  * and the Port can continue to transmit RSTP BPDUs. Setting mcheck has no
1202  * effect if stpVersion (17.20.12) is TRUE, i.e., the Bridge is operating in
1203  * STP Compatibility mode.
1204  */
1205 static void
1206 rstp_port_set_mcheck__(struct rstp_port *port, bool mcheck)
1207     OVS_REQUIRES(rstp_mutex)
1208 {
1209     if (mcheck == true && port->rstp->force_protocol_version >= 2) {
1210         port->mcheck = true;
1211
1212         VLOG_DBG("%s, port %u: set RSTP mcheck to %d", port->rstp->name,
1213                  port->port_number, mcheck);
1214     }
1215 }
1216
1217 /* Returns the designated bridge id. */
1218 rstp_identifier
1219 rstp_get_designated_id(const struct rstp *rstp)
1220     OVS_EXCLUDED(rstp_mutex)
1221 {
1222     rstp_identifier designated_id;
1223
1224     ovs_mutex_lock(&rstp_mutex);
1225     designated_id = rstp->root_priority.designated_bridge_id;
1226     ovs_mutex_unlock(&rstp_mutex);
1227
1228     return designated_id;
1229 }
1230
1231 /* Returns the root bridge id. */
1232 rstp_identifier
1233 rstp_get_root_id(const struct rstp *rstp)
1234     OVS_EXCLUDED(rstp_mutex)
1235 {
1236     rstp_identifier root_id;
1237
1238     ovs_mutex_lock(&rstp_mutex);
1239     root_id = rstp->root_priority.root_bridge_id;
1240     ovs_mutex_unlock(&rstp_mutex);
1241
1242     return root_id;
1243 }
1244
1245 /* Returns the designated port id. */
1246 uint16_t
1247 rstp_get_designated_port_id(const struct rstp *rstp)
1248     OVS_EXCLUDED(rstp_mutex)
1249 {
1250     uint16_t designated_port_id;
1251
1252     ovs_mutex_lock(&rstp_mutex);
1253     designated_port_id = rstp->root_priority.designated_port_id;
1254     ovs_mutex_unlock(&rstp_mutex);
1255
1256     return designated_port_id;
1257 }
1258
1259 /* Return the bridge port id. */
1260 uint16_t
1261 rstp_get_bridge_port_id(const struct rstp *rstp)
1262     OVS_EXCLUDED(rstp_mutex)
1263 {
1264     uint16_t bridge_port_id;
1265
1266     ovs_mutex_lock(&rstp_mutex);
1267     bridge_port_id = rstp->root_priority.bridge_port_id;
1268     ovs_mutex_unlock(&rstp_mutex);
1269
1270     return bridge_port_id;
1271 }
1272
1273 /* Returns true if the bridge believes to the be root of the spanning tree,
1274  * false otherwise.
1275  */
1276 bool
1277 rstp_is_root_bridge(const struct rstp *rstp)
1278     OVS_EXCLUDED(rstp_mutex)
1279 {
1280     bool is_root;
1281
1282     ovs_mutex_lock(&rstp_mutex);
1283     is_root = rstp->bridge_identifier ==
1284                 rstp->root_priority.designated_bridge_id;
1285     ovs_mutex_unlock(&rstp_mutex);
1286
1287     return is_root;
1288 }
1289
1290 /* Returns the bridge ID of the bridge currently believed to be the root. */
1291 rstp_identifier
1292 rstp_get_designated_root(const struct rstp *rstp)
1293     OVS_EXCLUDED(rstp_mutex)
1294 {
1295     rstp_identifier designated_root;
1296
1297     ovs_mutex_lock(&rstp_mutex);
1298     designated_root = rstp->root_priority.designated_bridge_id;
1299     ovs_mutex_unlock(&rstp_mutex);
1300
1301     return designated_root;
1302 }
1303
1304 /* Returns the port connecting 'rstp' to the root bridge, or a null pointer if
1305  * there is no such port.
1306  */
1307 struct rstp_port *
1308 rstp_get_root_port(struct rstp *rstp)
1309     OVS_EXCLUDED(rstp_mutex)
1310 {
1311     struct rstp_port *p;
1312
1313     ovs_mutex_lock(&rstp_mutex);
1314     HMAP_FOR_EACH (p, node, &rstp->ports) {
1315         if (p->port_id == rstp->root_port_id) {
1316             ovs_mutex_unlock(&rstp_mutex);
1317             return p;
1318         }
1319     }
1320     ovs_mutex_unlock(&rstp_mutex);
1321     return NULL;
1322 }
1323
1324 /* Returns the state of port 'p'. */
1325 enum rstp_state
1326 rstp_port_get_state(const struct rstp_port *p)
1327 {
1328     enum rstp_state state;
1329
1330     ovs_mutex_lock(&rstp_mutex);
1331     state = p->rstp_state;
1332     ovs_mutex_unlock(&rstp_mutex);
1333
1334     return state;
1335 }
1336
1337 /* Retrieves port status. */
1338 void
1339 rstp_port_get_status(const struct rstp_port *p, uint16_t *id,
1340                      enum rstp_state *state, enum rstp_port_role *role,
1341                      rstp_identifier *designated_bridge_id,
1342                      uint16_t *designated_port_id,
1343                      uint32_t *designated_path_cost, int *tx_count,
1344                      int *rx_count, int *error_count, int *uptime)
1345     OVS_EXCLUDED(rstp_mutex)
1346 {
1347     ovs_mutex_lock(&rstp_mutex);
1348     *id = p->port_id;
1349     *state = p->rstp_state;
1350     *role = p->role;
1351
1352     *designated_bridge_id = p->port_priority.designated_bridge_id;
1353     *designated_port_id = p->port_priority.designated_port_id;
1354     *designated_path_cost = p->port_priority.root_path_cost;
1355
1356     *tx_count = p->tx_count;
1357     *rx_count = p->rx_rstp_bpdu_cnt;
1358     *error_count = p->error_count;
1359     *uptime = p->uptime;
1360     ovs_mutex_unlock(&rstp_mutex);
1361 }
1362
1363 void
1364 rstp_port_set(struct rstp_port *port, uint16_t port_num, int priority,
1365               uint32_t path_cost, bool is_admin_edge, bool is_auto_edge,
1366               enum rstp_admin_point_to_point_mac_state admin_p2p_mac_state,
1367               bool admin_port_state, bool do_mcheck, void *aux)
1368     OVS_EXCLUDED(rstp_mutex)
1369 {
1370     ovs_mutex_lock(&rstp_mutex);
1371     port->aux = aux;
1372     rstp_port_set_priority__(port, priority);
1373     rstp_port_set_port_number__(port, port_num);
1374     rstp_port_set_path_cost__(port, path_cost);
1375     rstp_port_set_admin_edge__(port, is_admin_edge);
1376     rstp_port_set_auto_edge__(port, is_auto_edge);
1377     rstp_port_set_admin_point_to_point_mac__(port, admin_p2p_mac_state);
1378     rstp_port_set_administrative_bridge_port__(port, admin_port_state, false);
1379     rstp_port_set_mcheck__(port, do_mcheck);
1380     ovs_mutex_unlock(&rstp_mutex);
1381 }
1382
1383 /* Individual setters only used by test-rstp.c. */
1384 void
1385 rstp_port_set_priority(struct rstp_port *port, int priority)
1386     OVS_EXCLUDED(rstp_mutex)
1387 {
1388     ovs_mutex_lock(&rstp_mutex);
1389     rstp_port_set_priority__(port, priority);
1390     ovs_mutex_unlock(&rstp_mutex);
1391 }
1392
1393 void
1394 rstp_port_set_path_cost(struct rstp_port *port, uint32_t path_cost)
1395     OVS_EXCLUDED(rstp_mutex)
1396 {
1397     ovs_mutex_lock(&rstp_mutex);
1398     rstp_port_set_path_cost__(port, path_cost);
1399     ovs_mutex_unlock(&rstp_mutex);
1400 }
1401
1402 void
1403 rstp_port_set_aux(struct rstp_port *port, void *aux)
1404     OVS_EXCLUDED(rstp_mutex)
1405 {
1406     ovs_mutex_lock(&rstp_mutex);
1407     port->aux = aux;
1408     ovs_mutex_unlock(&rstp_mutex);
1409 }
1410
1411 /* Unixctl. */
1412 static struct rstp *
1413 rstp_find(const char *name)
1414     OVS_REQUIRES(rstp_mutex)
1415 {
1416     struct rstp *rstp;
1417
1418     LIST_FOR_EACH (rstp, node, all_rstps) {
1419         if (!strcmp(rstp->name, name)) {
1420             return rstp;
1421         }
1422     }
1423     return NULL;
1424 }
1425
1426 static void
1427 rstp_unixctl_tcn(struct unixctl_conn *conn, int argc,
1428                  const char *argv[], void *aux OVS_UNUSED)
1429     OVS_EXCLUDED(rstp_mutex)
1430 {
1431     ovs_mutex_lock(&rstp_mutex);
1432     if (argc > 1) {
1433         struct rstp *rstp = rstp_find(argv[1]);
1434         if (!rstp) {
1435             unixctl_command_reply_error(conn, "No such RSTP object");
1436             goto out;
1437         }
1438         rstp->changes = true;
1439         move_rstp__(rstp);
1440     } else {
1441         struct rstp *rstp;
1442         LIST_FOR_EACH (rstp, node, all_rstps) {
1443             rstp->changes = true;
1444             move_rstp__(rstp);
1445         }
1446     }
1447     unixctl_command_reply(conn, "OK");
1448
1449 out:
1450     ovs_mutex_unlock(&rstp_mutex);
1451 }