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