net/tipc/bcast.c

   1 /*
   2  * net/tipc/bcast.c: TIPC broadcast code
   3  *
   4  * Copyright (c) 2004-2006, Ericsson AB
   5  * Copyright (c) 2004, Intel Corporation.
   6  * Copyright (c) 2005, 2010-2011, Wind River Systems
   7  * All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions are met:
  11  *
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. Neither the names of the copyright holders nor the names of its
  18  *    contributors may be used to endorse or promote products derived from
  19  *    this software without specific prior written permission.
  20  *
  21  * Alternatively, this software may be distributed under the terms of the
  22  * GNU General Public License ("GPL") version 2 as published by the Free
  23  * Software Foundation.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  26  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  28  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  29  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  35  * POSSIBILITY OF SUCH DAMAGE.
  36  */
  37
  38 #include "core.h"
  39 #include "link.h"
  40 #include "port.h"
  41 #include "bcast.h"
  42 #include "name_distr.h"
  43
  44 #define MAX_PKT_DEFAULT_MCAST 1500      /* bcast link max packet size (fixed) */
  45
  46 #define BCLINK_WIN_DEFAULT 20           /* bcast link window size (default) */
  47
  48 /**
  49  * struct tipc_bcbearer_pair - a pair of bearers used by broadcast link
  50  * @primary: pointer to primary bearer
  51  * @secondary: pointer to secondary bearer
  52  *
  53  * Bearers must have same priority and same set of reachable destinations
  54  * to be paired.
  55  */
  56
  57 struct tipc_bcbearer_pair {
  58         struct tipc_bearer *primary;
  59         struct tipc_bearer *secondary;
  60 };
  61
  62 /**
  63  * struct tipc_bcbearer - bearer used by broadcast link
  64  * @bearer: (non-standard) broadcast bearer structure
  65  * @media: (non-standard) broadcast media structure
  66  * @bpairs: array of bearer pairs
  67  * @bpairs_temp: temporary array of bearer pairs used by tipc_bcbearer_sort()
  68  * @remains: temporary node map used by tipc_bcbearer_send()
  69  * @remains_new: temporary node map used tipc_bcbearer_send()
  70  *
  71  * Note: The fields labelled "temporary" are incorporated into the bearer
  72  * to avoid consuming potentially limited stack space through the use of
  73  * large local variables within multicast routines.  Concurrent access is
  74  * prevented through use of the spinlock "bc_lock".
  75  */
  76
  77 struct tipc_bcbearer {
  78         struct tipc_bearer bearer;
  79         struct tipc_media media;
  80         struct tipc_bcbearer_pair bpairs[MAX_BEARERS];
  81         struct tipc_bcbearer_pair bpairs_temp[TIPC_MAX_LINK_PRI + 1];
  82         struct tipc_node_map remains;
  83         struct tipc_node_map remains_new;
  84 };
  85
  86 /**
  87  * struct tipc_bclink - link used for broadcast messages
  88  * @link: (non-standard) broadcast link structure
  89  * @node: (non-standard) node structure representing b'cast link's peer node
  90  * @bcast_nodes: map of broadcast-capable nodes
  91  * @retransmit_to: node that most recently requested a retransmit
  92  *
  93  * Handles sequence numbering, fragmentation, bundling, etc.
  94  */
  95
  96 struct tipc_bclink {
  97         struct tipc_link link;
  98         struct tipc_node node;
  99         struct tipc_node_map bcast_nodes;
 100         struct tipc_node *retransmit_to;
 101 };
 102
 103 static struct tipc_bcbearer bcast_bearer;
 104 static struct tipc_bclink bcast_link;
 105
 106 static struct tipc_bcbearer *bcbearer = &bcast_bearer;
 107 static struct tipc_bclink *bclink = &bcast_link;
 108 static struct tipc_link *bcl = &bcast_link.link;
 109
 110 static DEFINE_SPINLOCK(bc_lock);
 111
 112 const char tipc_bclink_name[] = "broadcast-link";
 113
 114 static void tipc_nmap_diff(struct tipc_node_map *nm_a,
 115                            struct tipc_node_map *nm_b,
 116                            struct tipc_node_map *nm_diff);
 117
 118 static u32 bcbuf_acks(struct sk_buff *buf)
 119 {
 120         return (u32)(unsigned long)TIPC_SKB_CB(buf)->handle;
 121 }
 122
 123 static void bcbuf_set_acks(struct sk_buff *buf, u32 acks)
 124 {
 125         TIPC_SKB_CB(buf)->handle = (void *)(unsigned long)acks;
 126 }
 127
 128 static void bcbuf_decr_acks(struct sk_buff *buf)
 129 {
 130         bcbuf_set_acks(buf, bcbuf_acks(buf) - 1);
 131 }
 132
 133 void tipc_bclink_add_node(u32 addr)
 134 {
 135         spin_lock_bh(&bc_lock);
 136         tipc_nmap_add(&bclink->bcast_nodes, addr);
 137         spin_unlock_bh(&bc_lock);
 138 }
 139
 140 void tipc_bclink_remove_node(u32 addr)
 141 {
 142         spin_lock_bh(&bc_lock);
 143         tipc_nmap_remove(&bclink->bcast_nodes, addr);
 144         spin_unlock_bh(&bc_lock);
 145 }
 146
 147 static void bclink_set_last_sent(void)
 148 {
 149         if (bcl->next_out)
 150                 bcl->fsm_msg_cnt = mod(buf_seqno(bcl->next_out) - 1);
 151         else
 152                 bcl->fsm_msg_cnt = mod(bcl->next_out_no - 1);
 153 }
 154
 155 u32 tipc_bclink_get_last_sent(void)
 156 {
 157         return bcl->fsm_msg_cnt;
 158 }
 159
 160 static void bclink_update_last_sent(struct tipc_node *node, u32 seqno)
 161 {
 162         node->bclink.last_sent = less_eq(node->bclink.last_sent, seqno) ?
 163                                                 seqno : node->bclink.last_sent;
 164 }
 165
 166
 167 /*
 168  * tipc_bclink_retransmit_to - get most recent node to request retransmission
 169  *
 170  * Called with bc_lock locked
 171  */
 172
 173 struct tipc_node *tipc_bclink_retransmit_to(void)
 174 {
 175         return bclink->retransmit_to;
 176 }
 177
 178 /**
 179  * bclink_retransmit_pkt - retransmit broadcast packets
 180  * @after: sequence number of last packet to *not* retransmit
 181  * @to: sequence number of last packet to retransmit
 182  *
 183  * Called with bc_lock locked
 184  */
 185
 186 static void bclink_retransmit_pkt(u32 after, u32 to)
 187 {
 188         struct sk_buff *buf;
 189
 190         buf = bcl->first_out;
 191         while (buf && less_eq(buf_seqno(buf), after))
 192                 buf = buf->next;
 193         tipc_link_retransmit(bcl, buf, mod(to - after));
 194 }
 195
 196 /**
 197  * tipc_bclink_acknowledge - handle acknowledgement of broadcast packets
 198  * @n_ptr: node that sent acknowledgement info
 199  * @acked: broadcast sequence # that has been acknowledged
 200  *
 201  * Node is locked, bc_lock unlocked.
 202  */
 203
 204 void tipc_bclink_acknowledge(struct tipc_node *n_ptr, u32 acked)
 205 {
 206         struct sk_buff *crs;
 207         struct sk_buff *next;
 208         unsigned int released = 0;
 209
 210         spin_lock_bh(&bc_lock);
 211
 212         /* Bail out if tx queue is empty (no clean up is required) */
 213         crs = bcl->first_out;
 214         if (!crs)
 215                 goto exit;
 216
 217         /* Determine which messages need to be acknowledged */
 218         if (acked == INVALID_LINK_SEQ) {
 219                 /*
 220                  * Contact with specified node has been lost, so need to
 221                  * acknowledge sent messages only (if other nodes still exist)
 222                  * or both sent and unsent messages (otherwise)
 223                  */
 224                 if (bclink->bcast_nodes.count)
 225                         acked = bcl->fsm_msg_cnt;
 226                 else
 227                         acked = bcl->next_out_no;
 228         } else {
 229                 /*
 230                  * Bail out if specified sequence number does not correspond
 231                  * to a message that has been sent and not yet acknowledged
 232                  */
 233                 if (less(acked, buf_seqno(crs)) ||
 234                     less(bcl->fsm_msg_cnt, acked) ||
 235                     less_eq(acked, n_ptr->bclink.acked))
 236                         goto exit;
 237         }
 238
 239         /* Skip over packets that node has previously acknowledged */
 240         while (crs && less_eq(buf_seqno(crs), n_ptr->bclink.acked))
 241                 crs = crs->next;
 242
 243         /* Update packets that node is now acknowledging */
 244
 245         while (crs && less_eq(buf_seqno(crs), acked)) {
 246                 next = crs->next;
 247
 248                 if (crs != bcl->next_out)
 249                         bcbuf_decr_acks(crs);
 250                 else {
 251                         bcbuf_set_acks(crs, 0);
 252                         bcl->next_out = next;
 253                         bclink_set_last_sent();
 254                 }
 255
 256                 if (bcbuf_acks(crs) == 0) {
 257                         bcl->first_out = next;
 258                         bcl->out_queue_size--;
 259                         buf_discard(crs);
 260                         released = 1;
 261                 }
 262                 crs = next;
 263         }
 264         n_ptr->bclink.acked = acked;
 265
 266         /* Try resolving broadcast link congestion, if necessary */
 267
 268         if (unlikely(bcl->next_out)) {
 269                 tipc_link_push_queue(bcl);
 270                 bclink_set_last_sent();
 271         }
 272         if (unlikely(released && !list_empty(&bcl->waiting_ports)))
 273                 tipc_link_wakeup_ports(bcl, 0);
 274 exit:
 275         spin_unlock_bh(&bc_lock);
 276 }
 277
 278 /*
 279  * tipc_bclink_update_link_state - update broadcast link state
 280  *
 281  * tipc_net_lock and node lock set
 282  */
 283
 284 void tipc_bclink_update_link_state(struct tipc_node *n_ptr, u32 last_sent)
 285 {
 286         struct sk_buff *buf;
 287
 288         /* Ignore "stale" link state info */
 289
 290         if (less_eq(last_sent, n_ptr->bclink.last_in))
 291                 return;
 292
 293         /* Update link synchronization state; quit if in sync */
 294
 295         bclink_update_last_sent(n_ptr, last_sent);
 296
 297         if (n_ptr->bclink.last_sent == n_ptr->bclink.last_in)
 298                 return;
 299
 300         /* Update out-of-sync state; quit if loss is still unconfirmed */
 301
 302         if ((++n_ptr->bclink.oos_state) == 1) {
 303                 if (n_ptr->bclink.deferred_size < (TIPC_MIN_LINK_WIN / 2))
 304                         return;
 305                 n_ptr->bclink.oos_state++;
 306         }
 307
 308         /* Don't NACK if one has been recently sent (or seen) */
 309
 310         if (n_ptr->bclink.oos_state & 0x1)
 311                 return;
 312
 313         /* Send NACK */
 314
 315         buf = tipc_buf_acquire(INT_H_SIZE);
 316         if (buf) {
 317                 struct tipc_msg *msg = buf_msg(buf);
 318
 319                 tipc_msg_init(msg, BCAST_PROTOCOL, STATE_MSG,
 320                               INT_H_SIZE, n_ptr->addr);
 321                 msg_set_non_seq(msg, 1);
 322                 msg_set_mc_netid(msg, tipc_net_id);
 323                 msg_set_bcast_ack(msg, n_ptr->bclink.last_in);
 324                 msg_set_bcgap_after(msg, n_ptr->bclink.last_in);
 325                 msg_set_bcgap_to(msg, n_ptr->bclink.deferred_head
 326                                  ? buf_seqno(n_ptr->bclink.deferred_head) - 1
 327                                  : n_ptr->bclink.last_sent);
 328                 msg_set_bcast_tag(msg, tipc_own_tag);
 329
 330                 spin_lock_bh(&bc_lock);
 331                 tipc_bearer_send(&bcbearer->bearer, buf, NULL);
 332                 bcl->stats.sent_nacks++;
 333                 spin_unlock_bh(&bc_lock);
 334                 buf_discard(buf);
 335
 336                 n_ptr->bclink.oos_state++;
 337         }
 338 }
 339
 340 /*
 341  * bclink_peek_nack - monitor retransmission requests sent by other nodes
 342  *
 343  * Delay any upcoming NACK by this node if another node has already
 344  * requested the first message this node is going to ask for.
 345  *
 346  * Only tipc_net_lock set.
 347  */
 348
 349 static void bclink_peek_nack(struct tipc_msg *msg)
 350 {
 351         struct tipc_node *n_ptr = tipc_node_find(msg_destnode(msg));
 352
 353         if (unlikely(!n_ptr))
 354                 return;
 355
 356         tipc_node_lock(n_ptr);
 357
 358         if (n_ptr->bclink.supported &&
 359             (n_ptr->bclink.last_in != n_ptr->bclink.last_sent) &&
 360             (n_ptr->bclink.last_in == msg_bcgap_after(msg)))
 361                 n_ptr->bclink.oos_state = 2;
 362
 363         tipc_node_unlock(n_ptr);
 364 }
 365
 366 /*
 367  * tipc_bclink_send_msg - broadcast a packet to all nodes in cluster
 368  */
 369
 370 int tipc_bclink_send_msg(struct sk_buff *buf)
 371 {
 372         int res;
 373
 374         spin_lock_bh(&bc_lock);
 375
 376         if (!bclink->bcast_nodes.count) {
 377                 res = msg_data_sz(buf_msg(buf));
 378                 buf_discard(buf);
 379                 goto exit;
 380         }
 381
 382         res = tipc_link_send_buf(bcl, buf);
 383         if (likely(res >= 0)) {
 384                 bclink_set_last_sent();
 385                 bcl->stats.queue_sz_counts++;
 386                 bcl->stats.accu_queue_sz += bcl->out_queue_size;
 387         }
 388 exit:
 389         spin_unlock_bh(&bc_lock);
 390         return res;
 391 }
 392
 393 /**
 394  * tipc_bclink_recv_pkt - receive a broadcast packet, and deliver upwards
 395  *
 396  * tipc_net_lock is read_locked, no other locks set
 397  */
 398
 399 void tipc_bclink_recv_pkt(struct sk_buff *buf)
 400 {
 401         struct tipc_msg *msg = buf_msg(buf);
 402         struct tipc_node *node;
 403         u32 next_in;
 404         u32 seqno;
 405         int deferred;
 406
 407         /* Screen out unwanted broadcast messages */
 408
 409         if (msg_mc_netid(msg) != tipc_net_id)
 410                 goto exit;
 411
 412         node = tipc_node_find(msg_prevnode(msg));
 413         if (unlikely(!node))
 414                 goto exit;
 415
 416         tipc_node_lock(node);
 417         if (unlikely(!node->bclink.supported))
 418                 goto unlock;
 419
 420         /* Handle broadcast protocol message */
 421
 422         if (unlikely(msg_user(msg) == BCAST_PROTOCOL)) {
 423                 if (msg_type(msg) != STATE_MSG)
 424                         goto unlock;
 425                 if (msg_destnode(msg) == tipc_own_addr) {
 426                         tipc_bclink_acknowledge(node, msg_bcast_ack(msg));
 427                         tipc_node_unlock(node);
 428                         spin_lock_bh(&bc_lock);
 429                         bcl->stats.recv_nacks++;
 430                         bclink->retransmit_to = node;
 431                         bclink_retransmit_pkt(msg_bcgap_after(msg),
 432                                               msg_bcgap_to(msg));
 433                         spin_unlock_bh(&bc_lock);
 434                 } else {
 435                         tipc_node_unlock(node);
 436                         bclink_peek_nack(msg);
 437                 }
 438                 goto exit;
 439         }
 440
 441         /* Handle in-sequence broadcast message */
 442
 443         seqno = msg_seqno(msg);
 444         next_in = mod(node->bclink.last_in + 1);
 445
 446         if (likely(seqno == next_in)) {
 447                 bclink_update_last_sent(node, seqno);
 448 receive:
 449                 node->bclink.last_in = seqno;
 450                 node->bclink.oos_state = 0;
 451
 452                 spin_lock_bh(&bc_lock);
 453                 bcl->stats.recv_info++;
 454
 455                 /*
 456                  * Unicast an ACK periodically, ensuring that
 457                  * all nodes in the cluster don't ACK at the same time
 458                  */
 459
 460                 if (((seqno - tipc_own_addr) % TIPC_MIN_LINK_WIN) == 0) {
 461                         tipc_link_send_proto_msg(
 462                                 node->active_links[node->addr & 1],
 463                                 STATE_MSG, 0, 0, 0, 0, 0);
 464                         bcl->stats.sent_acks++;
 465                 }
 466
 467                 /* Deliver message to destination */
 468
 469                 if (likely(msg_isdata(msg))) {
 470                         spin_unlock_bh(&bc_lock);
 471                         tipc_node_unlock(node);
 472                         if (likely(msg_mcast(msg)))
 473                                 tipc_port_recv_mcast(buf, NULL);
 474                         else
 475                                 buf_discard(buf);
 476                 } else if (msg_user(msg) == MSG_BUNDLER) {
 477                         bcl->stats.recv_bundles++;
 478                         bcl->stats.recv_bundled += msg_msgcnt(msg);
 479                         spin_unlock_bh(&bc_lock);
 480                         tipc_node_unlock(node);
 481                         tipc_link_recv_bundle(buf);
 482                 } else if (msg_user(msg) == MSG_FRAGMENTER) {
 483                         bcl->stats.recv_fragments++;
 484                         if (tipc_link_recv_fragment(&node->bclink.defragm,
 485                                                     &buf, &msg))
 486                                 bcl->stats.recv_fragmented++;
 487                         spin_unlock_bh(&bc_lock);
 488                         tipc_node_unlock(node);
 489                         tipc_net_route_msg(buf);
 490                 } else if (msg_user(msg) == NAME_DISTRIBUTOR) {
 491                         spin_unlock_bh(&bc_lock);
 492                         tipc_node_unlock(node);
 493                         tipc_named_recv(buf);
 494                 } else {
 495                         spin_unlock_bh(&bc_lock);
 496                         tipc_node_unlock(node);
 497                         buf_discard(buf);
 498                 }
 499                 buf = NULL;
 500
 501                 /* Determine new synchronization state */
 502
 503                 tipc_node_lock(node);
 504                 if (unlikely(!tipc_node_is_up(node)))
 505                         goto unlock;
 506
 507                 if (node->bclink.last_in == node->bclink.last_sent)
 508                         goto unlock;
 509
 510                 if (!node->bclink.deferred_head) {
 511                         node->bclink.oos_state = 1;
 512                         goto unlock;
 513                 }
 514
 515                 msg = buf_msg(node->bclink.deferred_head);
 516                 seqno = msg_seqno(msg);
 517                 next_in = mod(next_in + 1);
 518                 if (seqno != next_in)
 519                         goto unlock;
 520
 521                 /* Take in-sequence message from deferred queue & deliver it */
 522
 523                 buf = node->bclink.deferred_head;
 524                 node->bclink.deferred_head = buf->next;
 525                 node->bclink.deferred_size--;
 526                 goto receive;
 527         }
 528
 529         /* Handle out-of-sequence broadcast message */
 530
 531         if (less(next_in, seqno)) {
 532                 deferred = tipc_link_defer_pkt(&node->bclink.deferred_head,
 533                                                &node->bclink.deferred_tail,
 534                                                buf);
 535                 node->bclink.deferred_size += deferred;
 536                 bclink_update_last_sent(node, seqno);
 537                 buf = NULL;
 538         } else
 539                 deferred = 0;
 540
 541         spin_lock_bh(&bc_lock);
 542
 543         if (deferred)
 544                 bcl->stats.deferred_recv++;
 545         else
 546                 bcl->stats.duplicates++;
 547
 548         spin_unlock_bh(&bc_lock);
 549
 550 unlock:
 551         tipc_node_unlock(node);
 552 exit:
 553         buf_discard(buf);
 554 }
 555
 556 u32 tipc_bclink_acks_missing(struct tipc_node *n_ptr)
 557 {
 558         return (n_ptr->bclink.supported &&
 559                 (tipc_bclink_get_last_sent() != n_ptr->bclink.acked));
 560 }
 561
 562
 563 /**
 564  * tipc_bcbearer_send - send a packet through the broadcast pseudo-bearer
 565  *
 566  * Send packet over as many bearers as necessary to reach all nodes
 567  * that have joined the broadcast link.
 568  *
 569  * Returns 0 (packet sent successfully) under all circumstances,
 570  * since the broadcast link's pseudo-bearer never blocks
 571  */
 572
 573 static int tipc_bcbearer_send(struct sk_buff *buf,
 574                               struct tipc_bearer *unused1,
 575                               struct tipc_media_addr *unused2)
 576 {
 577         int bp_index;
 578
 579         /*
 580          * Prepare broadcast link message for reliable transmission,
 581          * if first time trying to send it;
 582          * preparation is skipped for broadcast link protocol messages
 583          * since they are sent in an unreliable manner and don't need it
 584          */
 585
 586         if (likely(!msg_non_seq(buf_msg(buf)))) {
 587                 struct tipc_msg *msg;
 588
 589                 bcbuf_set_acks(buf, bclink->bcast_nodes.count);
 590                 msg = buf_msg(buf);
 591                 msg_set_non_seq(msg, 1);
 592                 msg_set_mc_netid(msg, tipc_net_id);
 593                 bcl->stats.sent_info++;
 594
 595                 if (WARN_ON(!bclink->bcast_nodes.count)) {
 596                         dump_stack();
 597                         return 0;
 598                 }
 599         }
 600
 601         /* Send buffer over bearers until all targets reached */
 602
 603         bcbearer->remains = bclink->bcast_nodes;
 604
 605         for (bp_index = 0; bp_index < MAX_BEARERS; bp_index++) {
 606                 struct tipc_bearer *p = bcbearer->bpairs[bp_index].primary;
 607                 struct tipc_bearer *s = bcbearer->bpairs[bp_index].secondary;
 608
 609                 if (!p)
 610                         break;  /* no more bearers to try */
 611
 612                 tipc_nmap_diff(&bcbearer->remains, &p->nodes, &bcbearer->remains_new);
 613                 if (bcbearer->remains_new.count == bcbearer->remains.count)
 614                         continue;       /* bearer pair doesn't add anything */
 615
 616                 if (p->blocked ||
 617                     p->media->send_msg(buf, p, &p->media->bcast_addr)) {
 618                         /* unable to send on primary bearer */
 619                         if (!s || s->blocked ||
 620                             s->media->send_msg(buf, s,
 621                                                &s->media->bcast_addr)) {
 622                                 /* unable to send on either bearer */
 623                                 continue;
 624                         }
 625                 }
 626
 627                 if (s) {
 628                         bcbearer->bpairs[bp_index].primary = s;
 629                         bcbearer->bpairs[bp_index].secondary = p;
 630                 }
 631
 632                 if (bcbearer->remains_new.count == 0)
 633                         break;  /* all targets reached */
 634
 635                 bcbearer->remains = bcbearer->remains_new;
 636         }
 637
 638         return 0;
 639 }
 640
 641 /**
 642  * tipc_bcbearer_sort - create sets of bearer pairs used by broadcast bearer
 643  */
 644
 645 void tipc_bcbearer_sort(void)
 646 {
 647         struct tipc_bcbearer_pair *bp_temp = bcbearer->bpairs_temp;
 648         struct tipc_bcbearer_pair *bp_curr;
 649         int b_index;
 650         int pri;
 651
 652         spin_lock_bh(&bc_lock);
 653
 654         /* Group bearers by priority (can assume max of two per priority) */
 655
 656         memset(bp_temp, 0, sizeof(bcbearer->bpairs_temp));
 657
 658         for (b_index = 0; b_index < MAX_BEARERS; b_index++) {
 659                 struct tipc_bearer *b = &tipc_bearers[b_index];
 660
 661                 if (!b->active || !b->nodes.count)
 662                         continue;
 663
 664                 if (!bp_temp[b->priority].primary)
 665                         bp_temp[b->priority].primary = b;
 666                 else
 667                         bp_temp[b->priority].secondary = b;
 668         }
 669
 670         /* Create array of bearer pairs for broadcasting */
 671
 672         bp_curr = bcbearer->bpairs;
 673         memset(bcbearer->bpairs, 0, sizeof(bcbearer->bpairs));
 674
 675         for (pri = TIPC_MAX_LINK_PRI; pri >= 0; pri--) {
 676
 677                 if (!bp_temp[pri].primary)
 678                         continue;
 679
 680                 bp_curr->primary = bp_temp[pri].primary;
 681
 682                 if (bp_temp[pri].secondary) {
 683                         if (tipc_nmap_equal(&bp_temp[pri].primary->nodes,
 684                                             &bp_temp[pri].secondary->nodes)) {
 685                                 bp_curr->secondary = bp_temp[pri].secondary;
 686                         } else {
 687                                 bp_curr++;
 688                                 bp_curr->primary = bp_temp[pri].secondary;
 689                         }
 690                 }
 691
 692                 bp_curr++;
 693         }
 694
 695         spin_unlock_bh(&bc_lock);
 696 }
 697
 698
 699 int tipc_bclink_stats(char *buf, const u32 buf_size)
 700 {
 701         struct print_buf pb;
 702
 703         if (!bcl)
 704                 return 0;
 705
 706         tipc_printbuf_init(&pb, buf, buf_size);
 707
 708         spin_lock_bh(&bc_lock);
 709
 710         tipc_printf(&pb, "Link <%s>\n"
 711                          "  Window:%u packets\n",
 712                     bcl->name, bcl->queue_limit[0]);
 713         tipc_printf(&pb, "  RX packets:%u fragments:%u/%u bundles:%u/%u\n",
 714                     bcl->stats.recv_info,
 715                     bcl->stats.recv_fragments,
 716                     bcl->stats.recv_fragmented,
 717                     bcl->stats.recv_bundles,
 718                     bcl->stats.recv_bundled);
 719         tipc_printf(&pb, "  TX packets:%u fragments:%u/%u bundles:%u/%u\n",
 720                     bcl->stats.sent_info,
 721                     bcl->stats.sent_fragments,
 722                     bcl->stats.sent_fragmented,
 723                     bcl->stats.sent_bundles,
 724                     bcl->stats.sent_bundled);
 725         tipc_printf(&pb, "  RX naks:%u defs:%u dups:%u\n",
 726                     bcl->stats.recv_nacks,
 727                     bcl->stats.deferred_recv,
 728                     bcl->stats.duplicates);
 729         tipc_printf(&pb, "  TX naks:%u acks:%u dups:%u\n",
 730                     bcl->stats.sent_nacks,
 731                     bcl->stats.sent_acks,
 732                     bcl->stats.retransmitted);
 733         tipc_printf(&pb, "  Congestion bearer:%u link:%u  Send queue max:%u avg:%u\n",
 734                     bcl->stats.bearer_congs,
 735                     bcl->stats.link_congs,
 736                     bcl->stats.max_queue_sz,
 737                     bcl->stats.queue_sz_counts
 738                     ? (bcl->stats.accu_queue_sz / bcl->stats.queue_sz_counts)
 739                     : 0);
 740
 741         spin_unlock_bh(&bc_lock);
 742         return tipc_printbuf_validate(&pb);
 743 }
 744
 745 int tipc_bclink_reset_stats(void)
 746 {
 747         if (!bcl)
 748                 return -ENOPROTOOPT;
 749
 750         spin_lock_bh(&bc_lock);
 751         memset(&bcl->stats, 0, sizeof(bcl->stats));
 752         spin_unlock_bh(&bc_lock);
 753         return 0;
 754 }
 755
 756 int tipc_bclink_set_queue_limits(u32 limit)
 757 {
 758         if (!bcl)
 759                 return -ENOPROTOOPT;
 760         if ((limit < TIPC_MIN_LINK_WIN) || (limit > TIPC_MAX_LINK_WIN))
 761                 return -EINVAL;
 762
 763         spin_lock_bh(&bc_lock);
 764         tipc_link_set_queue_limits(bcl, limit);
 765         spin_unlock_bh(&bc_lock);
 766         return 0;
 767 }
 768
 769 void tipc_bclink_init(void)
 770 {
 771         INIT_LIST_HEAD(&bcbearer->bearer.cong_links);
 772         bcbearer->bearer.media = &bcbearer->media;
 773         bcbearer->media.send_msg = tipc_bcbearer_send;
 774         sprintf(bcbearer->media.name, "tipc-broadcast");
 775
 776         INIT_LIST_HEAD(&bcl->waiting_ports);
 777         bcl->next_out_no = 1;
 778         spin_lock_init(&bclink->node.lock);
 779         bcl->owner = &bclink->node;
 780         bcl->max_pkt = MAX_PKT_DEFAULT_MCAST;
 781         tipc_link_set_queue_limits(bcl, BCLINK_WIN_DEFAULT);
 782         bcl->b_ptr = &bcbearer->bearer;
 783         bcl->state = WORKING_WORKING;
 784         strlcpy(bcl->name, tipc_bclink_name, TIPC_MAX_LINK_NAME);
 785 }
 786
 787 void tipc_bclink_stop(void)
 788 {
 789         spin_lock_bh(&bc_lock);
 790         tipc_link_stop(bcl);
 791         spin_unlock_bh(&bc_lock);
 792
 793         memset(bclink, 0, sizeof(*bclink));
 794         memset(bcbearer, 0, sizeof(*bcbearer));
 795 }
 796
 797
 798 /**
 799  * tipc_nmap_add - add a node to a node map
 800  */
 801
 802 void tipc_nmap_add(struct tipc_node_map *nm_ptr, u32 node)
 803 {
 804         int n = tipc_node(node);
 805         int w = n / WSIZE;
 806         u32 mask = (1 << (n % WSIZE));
 807
 808         if ((nm_ptr->map[w] & mask) == 0) {
 809                 nm_ptr->count++;
 810                 nm_ptr->map[w] |= mask;
 811         }
 812 }
 813
 814 /**
 815  * tipc_nmap_remove - remove a node from a node map
 816  */
 817
 818 void tipc_nmap_remove(struct tipc_node_map *nm_ptr, u32 node)
 819 {
 820         int n = tipc_node(node);
 821         int w = n / WSIZE;
 822         u32 mask = (1 << (n % WSIZE));
 823
 824         if ((nm_ptr->map[w] & mask) != 0) {
 825                 nm_ptr->map[w] &= ~mask;
 826                 nm_ptr->count--;
 827         }
 828 }
 829
 830 /**
 831  * tipc_nmap_diff - find differences between node maps
 832  * @nm_a: input node map A
 833  * @nm_b: input node map B
 834  * @nm_diff: output node map A-B (i.e. nodes of A that are not in B)
 835  */
 836
 837 static void tipc_nmap_diff(struct tipc_node_map *nm_a,
 838                            struct tipc_node_map *nm_b,
 839                            struct tipc_node_map *nm_diff)
 840 {
 841         int stop = ARRAY_SIZE(nm_a->map);
 842         int w;
 843         int b;
 844         u32 map;
 845
 846         memset(nm_diff, 0, sizeof(*nm_diff));
 847         for (w = 0; w < stop; w++) {
 848                 map = nm_a->map[w] ^ (nm_a->map[w] & nm_b->map[w]);
 849                 nm_diff->map[w] = map;
 850                 if (map != 0) {
 851                         for (b = 0 ; b < WSIZE; b++) {
 852                                 if (map & (1 << b))
 853                                         nm_diff->count++;
 854                         }
 855                 }
 856         }
 857 }
 858
 859 /**
 860  * tipc_port_list_add - add a port to a port list, ensuring no duplicates
 861  */
 862
 863 void tipc_port_list_add(struct tipc_port_list *pl_ptr, u32 port)
 864 {
 865         struct tipc_port_list *item = pl_ptr;
 866         int i;
 867         int item_sz = PLSIZE;
 868         int cnt = pl_ptr->count;
 869
 870         for (; ; cnt -= item_sz, item = item->next) {
 871                 if (cnt < PLSIZE)
 872                         item_sz = cnt;
 873                 for (i = 0; i < item_sz; i++)
 874                         if (item->ports[i] == port)
 875                                 return;
 876                 if (i < PLSIZE) {
 877                         item->ports[i] = port;
 878                         pl_ptr->count++;
 879                         return;
 880                 }
 881                 if (!item->next) {
 882                         item->next = kmalloc(sizeof(*item), GFP_ATOMIC);
 883                         if (!item->next) {
 884                                 warn("Incomplete multicast delivery, no memory\n");
 885                                 return;
 886                         }
 887                         item->next->next = NULL;
 888                 }
 889         }
 890 }
 891
 892 /**
 893  * tipc_port_list_free - free dynamically created entries in port_list chain
 894  *
 895  */
 896
 897 void tipc_port_list_free(struct tipc_port_list *pl_ptr)
 898 {
 899         struct tipc_port_list *item;
 900         struct tipc_port_list *next;
 901
 902         for (item = pl_ptr->next; item; item = next) {
 903                 next = item->next;
 904                 kfree(item);
 905         }
 906 }
 907