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, 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 "msg.h"
  40 #include "dbg.h"
  41 #include "link.h"
  42 #include "net.h"
  43 #include "node.h"
  44 #include "port.h"
  45 #include "addr.h"
  46 #include "node_subscr.h"
  47 #include "name_distr.h"
  48 #include "bearer.h"
  49 #include "name_table.h"
  50 #include "bcast.h"
  51
  52 #define MAX_PKT_DEFAULT_MCAST 1500      /* bcast link max packet size (fixed) */
  53
  54 #define BCLINK_WIN_DEFAULT 20           /* bcast link window size (default) */
  55
  56 #define BCLINK_LOG_BUF_SIZE 0
  57
  58 /*
  59  * Loss rate for incoming broadcast frames; used to test retransmission code.
  60  * Set to N to cause every N'th frame to be discarded; 0 => don't discard any.
  61  */
  62
  63 #define TIPC_BCAST_LOSS_RATE 0
  64
  65 /**
  66  * struct bcbearer_pair - a pair of bearers used by broadcast link
  67  * @primary: pointer to primary bearer
  68  * @secondary: pointer to secondary bearer
  69  *
  70  * Bearers must have same priority and same set of reachable destinations
  71  * to be paired.
  72  */
  73
  74 struct bcbearer_pair {
  75         struct bearer *primary;
  76         struct bearer *secondary;
  77 };
  78
  79 /**
  80  * struct bcbearer - bearer used by broadcast link
  81  * @bearer: (non-standard) broadcast bearer structure
  82  * @media: (non-standard) broadcast media structure
  83  * @bpairs: array of bearer pairs
  84  * @bpairs_temp: array of bearer pairs used during creation of "bpairs"
  85  */
  86
  87 struct bcbearer {
  88         struct bearer bearer;
  89         struct media media;
  90         struct bcbearer_pair bpairs[MAX_BEARERS];
  91         struct bcbearer_pair bpairs_temp[TIPC_MAX_LINK_PRI + 1];
  92 };
  93
  94 /**
  95  * struct bclink - link used for broadcast messages
  96  * @link: (non-standard) broadcast link structure
  97  * @node: (non-standard) node structure representing b'cast link's peer node
  98  *
  99  * Handles sequence numbering, fragmentation, bundling, etc.
 100  */
 101
 102 struct bclink {
 103         struct link link;
 104         struct node node;
 105 };
 106
 107
 108 static struct bcbearer *bcbearer = NULL;
 109 static struct bclink *bclink = NULL;
 110 static struct link *bcl = NULL;
 111 static spinlock_t bc_lock = SPIN_LOCK_UNLOCKED;
 112
 113 char tipc_bclink_name[] = "multicast-link";
 114
 115
 116 static u32 buf_seqno(struct sk_buff *buf)
 117 {
 118         return msg_seqno(buf_msg(buf));
 119 }
 120
 121 static u32 bcbuf_acks(struct sk_buff *buf)
 122 {
 123         return (u32)(unsigned long)TIPC_SKB_CB(buf)->handle;
 124 }
 125
 126 static void bcbuf_set_acks(struct sk_buff *buf, u32 acks)
 127 {
 128         TIPC_SKB_CB(buf)->handle = (void *)(unsigned long)acks;
 129 }
 130
 131 static void bcbuf_decr_acks(struct sk_buff *buf)
 132 {
 133         bcbuf_set_acks(buf, bcbuf_acks(buf) - 1);
 134 }
 135
 136
 137 /**
 138  * bclink_set_gap - set gap according to contents of current deferred pkt queue
 139  *
 140  * Called with 'node' locked, bc_lock unlocked
 141  */
 142
 143 static void bclink_set_gap(struct node *n_ptr)
 144 {
 145         struct sk_buff *buf = n_ptr->bclink.deferred_head;
 146
 147         n_ptr->bclink.gap_after = n_ptr->bclink.gap_to =
 148                 mod(n_ptr->bclink.last_in);
 149         if (unlikely(buf != NULL))
 150                 n_ptr->bclink.gap_to = mod(buf_seqno(buf) - 1);
 151 }
 152
 153 /**
 154  * bclink_ack_allowed - test if ACK or NACK message can be sent at this moment
 155  *
 156  * This mechanism endeavours to prevent all nodes in network from trying
 157  * to ACK or NACK at the same time.
 158  *
 159  * Note: TIPC uses a different trigger to distribute ACKs than it does to
 160  *       distribute NACKs, but tries to use the same spacing (divide by 16).
 161  */
 162
 163 static int bclink_ack_allowed(u32 n)
 164 {
 165         return((n % TIPC_MIN_LINK_WIN) == tipc_own_tag);
 166 }
 167
 168
 169 /**
 170  * bclink_retransmit_pkt - retransmit broadcast packets
 171  * @after: sequence number of last packet to *not* retransmit
 172  * @to: sequence number of last packet to retransmit
 173  *
 174  * Called with bc_lock locked
 175  */
 176
 177 static void bclink_retransmit_pkt(u32 after, u32 to)
 178 {
 179         struct sk_buff *buf;
 180
 181         buf = bcl->first_out;
 182         while (buf && less_eq(buf_seqno(buf), after)) {
 183                 buf = buf->next;
 184         }
 185         tipc_link_retransmit(bcl, buf, mod(to - after));
 186 }
 187
 188 /**
 189  * tipc_bclink_acknowledge - handle acknowledgement of broadcast packets
 190  * @n_ptr: node that sent acknowledgement info
 191  * @acked: broadcast sequence # that has been acknowledged
 192  *
 193  * Node is locked, bc_lock unlocked.
 194  */
 195
 196 void tipc_bclink_acknowledge(struct node *n_ptr, u32 acked)
 197 {
 198         struct sk_buff *crs;
 199         struct sk_buff *next;
 200         unsigned int released = 0;
 201
 202         if (less_eq(acked, n_ptr->bclink.acked))
 203                 return;
 204
 205         spin_lock_bh(&bc_lock);
 206
 207         /* Skip over packets that node has previously acknowledged */
 208
 209         crs = bcl->first_out;
 210         while (crs && less_eq(buf_seqno(crs), n_ptr->bclink.acked)) {
 211                 crs = crs->next;
 212         }
 213
 214         /* Update packets that node is now acknowledging */
 215
 216         while (crs && less_eq(buf_seqno(crs), acked)) {
 217                 next = crs->next;
 218                 bcbuf_decr_acks(crs);
 219                 if (bcbuf_acks(crs) == 0) {
 220                         bcl->first_out = next;
 221                         bcl->out_queue_size--;
 222                         buf_discard(crs);
 223                         released = 1;
 224                 }
 225                 crs = next;
 226         }
 227         n_ptr->bclink.acked = acked;
 228
 229         /* Try resolving broadcast link congestion, if necessary */
 230
 231         if (unlikely(bcl->next_out))
 232                 tipc_link_push_queue(bcl);
 233         if (unlikely(released && !list_empty(&bcl->waiting_ports)))
 234                 tipc_link_wakeup_ports(bcl, 0);
 235         spin_unlock_bh(&bc_lock);
 236 }
 237
 238 /**
 239  * bclink_send_ack - unicast an ACK msg
 240  *
 241  * tipc_net_lock and node lock set
 242  */
 243
 244 static void bclink_send_ack(struct node *n_ptr)
 245 {
 246         struct link *l_ptr = n_ptr->active_links[n_ptr->addr & 1];
 247
 248         if (l_ptr != NULL)
 249                 tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
 250 }
 251
 252 /**
 253  * bclink_send_nack- broadcast a NACK msg
 254  *
 255  * tipc_net_lock and node lock set
 256  */
 257
 258 static void bclink_send_nack(struct node *n_ptr)
 259 {
 260         struct sk_buff *buf;
 261         struct tipc_msg *msg;
 262
 263         if (!less(n_ptr->bclink.gap_after, n_ptr->bclink.gap_to))
 264                 return;
 265
 266         buf = buf_acquire(INT_H_SIZE);
 267         if (buf) {
 268                 msg = buf_msg(buf);
 269                 msg_init(msg, BCAST_PROTOCOL, STATE_MSG,
 270                          TIPC_OK, INT_H_SIZE, n_ptr->addr);
 271                 msg_set_mc_netid(msg, tipc_net_id);
 272                 msg_set_bcast_ack(msg, mod(n_ptr->bclink.last_in));
 273                 msg_set_bcgap_after(msg, n_ptr->bclink.gap_after);
 274                 msg_set_bcgap_to(msg, n_ptr->bclink.gap_to);
 275                 msg_set_bcast_tag(msg, tipc_own_tag);
 276
 277                 if (tipc_bearer_send(&bcbearer->bearer, buf, NULL)) {
 278                         bcl->stats.sent_nacks++;
 279                         buf_discard(buf);
 280                 } else {
 281                         tipc_bearer_schedule(bcl->b_ptr, bcl);
 282                         bcl->proto_msg_queue = buf;
 283                         bcl->stats.bearer_congs++;
 284                 }
 285
 286                 /*
 287                  * Ensure we doesn't send another NACK msg to the node
 288                  * until 16 more deferred messages arrive from it
 289                  * (i.e. helps prevent all nodes from NACK'ing at same time)
 290                  */
 291
 292                 n_ptr->bclink.nack_sync = tipc_own_tag;
 293         }
 294 }
 295
 296 /**
 297  * tipc_bclink_check_gap - send a NACK if a sequence gap exists
 298  *
 299  * tipc_net_lock and node lock set
 300  */
 301
 302 void tipc_bclink_check_gap(struct node *n_ptr, u32 last_sent)
 303 {
 304         if (!n_ptr->bclink.supported ||
 305             less_eq(last_sent, mod(n_ptr->bclink.last_in)))
 306                 return;
 307
 308         bclink_set_gap(n_ptr);
 309         if (n_ptr->bclink.gap_after == n_ptr->bclink.gap_to)
 310                 n_ptr->bclink.gap_to = last_sent;
 311         bclink_send_nack(n_ptr);
 312 }
 313
 314 /**
 315  * tipc_bclink_peek_nack - process a NACK msg meant for another node
 316  *
 317  * Only tipc_net_lock set.
 318  */
 319
 320 static void tipc_bclink_peek_nack(u32 dest, u32 sender_tag, u32 gap_after, u32 gap_to)
 321 {
 322         struct node *n_ptr = tipc_node_find(dest);
 323         u32 my_after, my_to;
 324
 325         if (unlikely(!n_ptr || !tipc_node_is_up(n_ptr)))
 326                 return;
 327         tipc_node_lock(n_ptr);
 328         /*
 329          * Modify gap to suppress unnecessary NACKs from this node
 330          */
 331         my_after = n_ptr->bclink.gap_after;
 332         my_to = n_ptr->bclink.gap_to;
 333
 334         if (less_eq(gap_after, my_after)) {
 335                 if (less(my_after, gap_to) && less(gap_to, my_to))
 336                         n_ptr->bclink.gap_after = gap_to;
 337                 else if (less_eq(my_to, gap_to))
 338                         n_ptr->bclink.gap_to = n_ptr->bclink.gap_after;
 339         } else if (less_eq(gap_after, my_to)) {
 340                 if (less_eq(my_to, gap_to))
 341                         n_ptr->bclink.gap_to = gap_after;
 342         } else {
 343                 /*
 344                  * Expand gap if missing bufs not in deferred queue:
 345                  */
 346                 struct sk_buff *buf = n_ptr->bclink.deferred_head;
 347                 u32 prev = n_ptr->bclink.gap_to;
 348
 349                 for (; buf; buf = buf->next) {
 350                         u32 seqno = buf_seqno(buf);
 351
 352                         if (mod(seqno - prev) != 1) {
 353                                 buf = NULL;
 354                                 break;
 355                         }
 356                         if (seqno == gap_after)
 357                                 break;
 358                         prev = seqno;
 359                 }
 360                 if (buf == NULL)
 361                         n_ptr->bclink.gap_to = gap_after;
 362         }
 363         /*
 364          * Some nodes may send a complementary NACK now:
 365          */
 366         if (bclink_ack_allowed(sender_tag + 1)) {
 367                 if (n_ptr->bclink.gap_to != n_ptr->bclink.gap_after) {
 368                         bclink_send_nack(n_ptr);
 369                         bclink_set_gap(n_ptr);
 370                 }
 371         }
 372         tipc_node_unlock(n_ptr);
 373 }
 374
 375 /**
 376  * tipc_bclink_send_msg - broadcast a packet to all nodes in cluster
 377  */
 378
 379 int tipc_bclink_send_msg(struct sk_buff *buf)
 380 {
 381         int res;
 382
 383         spin_lock_bh(&bc_lock);
 384
 385         res = tipc_link_send_buf(bcl, buf);
 386         if (unlikely(res == -ELINKCONG))
 387                 buf_discard(buf);
 388         else
 389                 bcl->stats.sent_info++;
 390
 391         if (bcl->out_queue_size > bcl->stats.max_queue_sz)
 392                 bcl->stats.max_queue_sz = bcl->out_queue_size;
 393         bcl->stats.queue_sz_counts++;
 394         bcl->stats.accu_queue_sz += bcl->out_queue_size;
 395
 396         spin_unlock_bh(&bc_lock);
 397         return res;
 398 }
 399
 400 /**
 401  * tipc_bclink_recv_pkt - receive a broadcast packet, and deliver upwards
 402  *
 403  * tipc_net_lock is read_locked, no other locks set
 404  */
 405
 406 void tipc_bclink_recv_pkt(struct sk_buff *buf)
 407 {
 408 #if (TIPC_BCAST_LOSS_RATE)
 409         static int rx_count = 0;
 410 #endif
 411         struct tipc_msg *msg = buf_msg(buf);
 412         struct node* node = tipc_node_find(msg_prevnode(msg));
 413         u32 next_in;
 414         u32 seqno;
 415         struct sk_buff *deferred;
 416
 417         msg_dbg(msg, "<BC<<<");
 418
 419         if (unlikely(!node || !tipc_node_is_up(node) || !node->bclink.supported ||
 420                      (msg_mc_netid(msg) != tipc_net_id))) {
 421                 buf_discard(buf);
 422                 return;
 423         }
 424
 425         if (unlikely(msg_user(msg) == BCAST_PROTOCOL)) {
 426                 msg_dbg(msg, "<BCNACK<<<");
 427                 if (msg_destnode(msg) == tipc_own_addr) {
 428                         tipc_node_lock(node);
 429                         tipc_bclink_acknowledge(node, msg_bcast_ack(msg));
 430                         tipc_node_unlock(node);
 431                         spin_lock_bh(&bc_lock);
 432                         bcl->stats.recv_nacks++;
 433                         bcl->owner->next = node;   /* remember requestor */
 434                         bclink_retransmit_pkt(msg_bcgap_after(msg),
 435                                               msg_bcgap_to(msg));
 436                         bcl->owner->next = NULL;
 437                         spin_unlock_bh(&bc_lock);
 438                 } else {
 439                         tipc_bclink_peek_nack(msg_destnode(msg),
 440                                               msg_bcast_tag(msg),
 441                                               msg_bcgap_after(msg),
 442                                               msg_bcgap_to(msg));
 443                 }
 444                 buf_discard(buf);
 445                 return;
 446         }
 447
 448 #if (TIPC_BCAST_LOSS_RATE)
 449         if (++rx_count == TIPC_BCAST_LOSS_RATE) {
 450                 rx_count = 0;
 451                 buf_discard(buf);
 452                 return;
 453         }
 454 #endif
 455
 456         tipc_node_lock(node);
 457 receive:
 458         deferred = node->bclink.deferred_head;
 459         next_in = mod(node->bclink.last_in + 1);
 460         seqno = msg_seqno(msg);
 461
 462         if (likely(seqno == next_in)) {
 463                 bcl->stats.recv_info++;
 464                 node->bclink.last_in++;
 465                 bclink_set_gap(node);
 466                 if (unlikely(bclink_ack_allowed(seqno))) {
 467                         bclink_send_ack(node);
 468                         bcl->stats.sent_acks++;
 469                 }
 470                 if (likely(msg_isdata(msg))) {
 471                         tipc_node_unlock(node);
 472                         tipc_port_recv_mcast(buf, NULL);
 473                 } else if (msg_user(msg) == MSG_BUNDLER) {
 474                         bcl->stats.recv_bundles++;
 475                         bcl->stats.recv_bundled += msg_msgcnt(msg);
 476                         tipc_node_unlock(node);
 477                         tipc_link_recv_bundle(buf);
 478                 } else if (msg_user(msg) == MSG_FRAGMENTER) {
 479                         bcl->stats.recv_fragments++;
 480                         if (tipc_link_recv_fragment(&node->bclink.defragm,
 481                                                     &buf, &msg))
 482                                 bcl->stats.recv_fragmented++;
 483                         tipc_node_unlock(node);
 484                         tipc_net_route_msg(buf);
 485                 } else {
 486                         tipc_node_unlock(node);
 487                         tipc_net_route_msg(buf);
 488                 }
 489                 if (deferred && (buf_seqno(deferred) == mod(next_in + 1))) {
 490                         tipc_node_lock(node);
 491                         buf = deferred;
 492                         msg = buf_msg(buf);
 493                         node->bclink.deferred_head = deferred->next;
 494                         goto receive;
 495                 }
 496                 return;
 497         } else if (less(next_in, seqno)) {
 498                 u32 gap_after = node->bclink.gap_after;
 499                 u32 gap_to = node->bclink.gap_to;
 500
 501                 if (tipc_link_defer_pkt(&node->bclink.deferred_head,
 502                                         &node->bclink.deferred_tail,
 503                                         buf)) {
 504                         node->bclink.nack_sync++;
 505                         bcl->stats.deferred_recv++;
 506                         if (seqno == mod(gap_after + 1))
 507                                 node->bclink.gap_after = seqno;
 508                         else if (less(gap_after, seqno) && less(seqno, gap_to))
 509                                 node->bclink.gap_to = seqno;
 510                 }
 511                 if (bclink_ack_allowed(node->bclink.nack_sync)) {
 512                         if (gap_to != gap_after)
 513                                 bclink_send_nack(node);
 514                         bclink_set_gap(node);
 515                 }
 516         } else {
 517                 bcl->stats.duplicates++;
 518                 buf_discard(buf);
 519         }
 520         tipc_node_unlock(node);
 521 }
 522
 523 u32 tipc_bclink_get_last_sent(void)
 524 {
 525         u32 last_sent = mod(bcl->next_out_no - 1);
 526
 527         if (bcl->next_out)
 528                 last_sent = mod(buf_seqno(bcl->next_out) - 1);
 529         return last_sent;
 530 }
 531
 532 u32 tipc_bclink_acks_missing(struct node *n_ptr)
 533 {
 534         return (n_ptr->bclink.supported &&
 535                 (tipc_bclink_get_last_sent() != n_ptr->bclink.acked));
 536 }
 537
 538
 539 /**
 540  * tipc_bcbearer_send - send a packet through the broadcast pseudo-bearer
 541  *
 542  * Send through as many bearers as necessary to reach all nodes
 543  * that support TIPC multicasting.
 544  *
 545  * Returns 0 if packet sent successfully, non-zero if not
 546  */
 547
 548 static int tipc_bcbearer_send(struct sk_buff *buf,
 549                               struct tipc_bearer *unused1,
 550                               struct tipc_media_addr *unused2)
 551 {
 552         static int send_count = 0;
 553
 554         struct node_map *remains;
 555         struct node_map *remains_new;
 556         struct node_map *remains_tmp;
 557         int bp_index;
 558         int swap_time;
 559         int err;
 560
 561         /* Prepare buffer for broadcasting (if first time trying to send it) */
 562
 563         if (likely(!msg_non_seq(buf_msg(buf)))) {
 564                 struct tipc_msg *msg;
 565
 566                 assert(tipc_cltr_bcast_nodes.count != 0);
 567                 bcbuf_set_acks(buf, tipc_cltr_bcast_nodes.count);
 568                 msg = buf_msg(buf);
 569                 msg_set_non_seq(msg);
 570                 msg_set_mc_netid(msg, tipc_net_id);
 571         }
 572
 573         /* Determine if bearer pairs should be swapped following this attempt */
 574
 575         if ((swap_time = (++send_count >= 10)))
 576                 send_count = 0;
 577
 578         /* Send buffer over bearers until all targets reached */
 579
 580         remains = kmalloc(sizeof(struct node_map), GFP_ATOMIC);
 581         remains_new = kmalloc(sizeof(struct node_map), GFP_ATOMIC);
 582         *remains = tipc_cltr_bcast_nodes;
 583
 584         for (bp_index = 0; bp_index < MAX_BEARERS; bp_index++) {
 585                 struct bearer *p = bcbearer->bpairs[bp_index].primary;
 586                 struct bearer *s = bcbearer->bpairs[bp_index].secondary;
 587
 588                 if (!p)
 589                         break;  /* no more bearers to try */
 590
 591                 tipc_nmap_diff(remains, &p->nodes, remains_new);
 592                 if (remains_new->count == remains->count)
 593                         continue;       /* bearer pair doesn't add anything */
 594
 595                 if (!p->publ.blocked &&
 596                     !p->media->send_msg(buf, &p->publ, &p->media->bcast_addr)) {
 597                         if (swap_time && s && !s->publ.blocked)
 598                                 goto swap;
 599                         else
 600                                 goto update;
 601                 }
 602
 603                 if (!s || s->publ.blocked ||
 604                     s->media->send_msg(buf, &s->publ, &s->media->bcast_addr))
 605                         continue;       /* unable to send using bearer pair */
 606 swap:
 607                 bcbearer->bpairs[bp_index].primary = s;
 608                 bcbearer->bpairs[bp_index].secondary = p;
 609 update:
 610                 if (remains_new->count == 0) {
 611                         err = TIPC_OK;
 612                         goto out;
 613                 }
 614
 615                 /* swap map */
 616                 remains_tmp = remains;
 617                 remains = remains_new;
 618                 remains_new = remains_tmp;
 619         }
 620
 621         /* Unable to reach all targets */
 622
 623         bcbearer->bearer.publ.blocked = 1;
 624         bcl->stats.bearer_congs++;
 625         err = ~TIPC_OK;
 626
 627  out:
 628         kfree(remains_new);
 629         kfree(remains);
 630         return err;
 631 }
 632
 633 /**
 634  * tipc_bcbearer_sort - create sets of bearer pairs used by broadcast bearer
 635  */
 636
 637 void tipc_bcbearer_sort(void)
 638 {
 639         struct bcbearer_pair *bp_temp = bcbearer->bpairs_temp;
 640         struct bcbearer_pair *bp_curr;
 641         int b_index;
 642         int pri;
 643
 644         spin_lock_bh(&bc_lock);
 645
 646         /* Group bearers by priority (can assume max of two per priority) */
 647
 648         memset(bp_temp, 0, sizeof(bcbearer->bpairs_temp));
 649
 650         for (b_index = 0; b_index < MAX_BEARERS; b_index++) {
 651                 struct bearer *b = &tipc_bearers[b_index];
 652
 653                 if (!b->active || !b->nodes.count)
 654                         continue;
 655
 656                 if (!bp_temp[b->priority].primary)
 657                         bp_temp[b->priority].primary = b;
 658                 else
 659                         bp_temp[b->priority].secondary = b;
 660         }
 661
 662         /* Create array of bearer pairs for broadcasting */
 663
 664         bp_curr = bcbearer->bpairs;
 665         memset(bcbearer->bpairs, 0, sizeof(bcbearer->bpairs));
 666
 667         for (pri = TIPC_MAX_LINK_PRI; pri >= 0; pri--) {
 668
 669                 if (!bp_temp[pri].primary)
 670                         continue;
 671
 672                 bp_curr->primary = bp_temp[pri].primary;
 673
 674                 if (bp_temp[pri].secondary) {
 675                         if (tipc_nmap_equal(&bp_temp[pri].primary->nodes,
 676                                             &bp_temp[pri].secondary->nodes)) {
 677                                 bp_curr->secondary = bp_temp[pri].secondary;
 678                         } else {
 679                                 bp_curr++;
 680                                 bp_curr->primary = bp_temp[pri].secondary;
 681                         }
 682                 }
 683
 684                 bp_curr++;
 685         }
 686
 687         spin_unlock_bh(&bc_lock);
 688 }
 689
 690 /**
 691  * tipc_bcbearer_push - resolve bearer congestion
 692  *
 693  * Forces bclink to push out any unsent packets, until all packets are gone
 694  * or congestion reoccurs.
 695  * No locks set when function called
 696  */
 697
 698 void tipc_bcbearer_push(void)
 699 {
 700         struct bearer *b_ptr;
 701
 702         spin_lock_bh(&bc_lock);
 703         b_ptr = &bcbearer->bearer;
 704         if (b_ptr->publ.blocked) {
 705                 b_ptr->publ.blocked = 0;
 706                 tipc_bearer_lock_push(b_ptr);
 707         }
 708         spin_unlock_bh(&bc_lock);
 709 }
 710
 711
 712 int tipc_bclink_stats(char *buf, const u32 buf_size)
 713 {
 714         struct print_buf pb;
 715
 716         if (!bcl)
 717                 return 0;
 718
 719         tipc_printbuf_init(&pb, buf, buf_size);
 720
 721         spin_lock_bh(&bc_lock);
 722
 723         tipc_printf(&pb, "Link <%s>\n"
 724                          "  Window:%u packets\n",
 725                     bcl->name, bcl->queue_limit[0]);
 726         tipc_printf(&pb, "  RX packets:%u fragments:%u/%u bundles:%u/%u\n",
 727                     bcl->stats.recv_info,
 728                     bcl->stats.recv_fragments,
 729                     bcl->stats.recv_fragmented,
 730                     bcl->stats.recv_bundles,
 731                     bcl->stats.recv_bundled);
 732         tipc_printf(&pb, "  TX packets:%u fragments:%u/%u bundles:%u/%u\n",
 733                     bcl->stats.sent_info,
 734                     bcl->stats.sent_fragments,
 735                     bcl->stats.sent_fragmented,
 736                     bcl->stats.sent_bundles,
 737                     bcl->stats.sent_bundled);
 738         tipc_printf(&pb, "  RX naks:%u defs:%u dups:%u\n",
 739                     bcl->stats.recv_nacks,
 740                     bcl->stats.deferred_recv,
 741                     bcl->stats.duplicates);
 742         tipc_printf(&pb, "  TX naks:%u acks:%u dups:%u\n",
 743                     bcl->stats.sent_nacks,
 744                     bcl->stats.sent_acks,
 745                     bcl->stats.retransmitted);
 746         tipc_printf(&pb, "  Congestion bearer:%u link:%u  Send queue max:%u avg:%u\n",
 747                     bcl->stats.bearer_congs,
 748                     bcl->stats.link_congs,
 749                     bcl->stats.max_queue_sz,
 750                     bcl->stats.queue_sz_counts
 751                     ? (bcl->stats.accu_queue_sz / bcl->stats.queue_sz_counts)
 752                     : 0);
 753
 754         spin_unlock_bh(&bc_lock);
 755         return tipc_printbuf_validate(&pb);
 756 }
 757
 758 int tipc_bclink_reset_stats(void)
 759 {
 760         if (!bcl)
 761                 return -ENOPROTOOPT;
 762
 763         spin_lock_bh(&bc_lock);
 764         memset(&bcl->stats, 0, sizeof(bcl->stats));
 765         spin_unlock_bh(&bc_lock);
 766         return TIPC_OK;
 767 }
 768
 769 int tipc_bclink_set_queue_limits(u32 limit)
 770 {
 771         if (!bcl)
 772                 return -ENOPROTOOPT;
 773         if ((limit < TIPC_MIN_LINK_WIN) || (limit > TIPC_MAX_LINK_WIN))
 774                 return -EINVAL;
 775
 776         spin_lock_bh(&bc_lock);
 777         tipc_link_set_queue_limits(bcl, limit);
 778         spin_unlock_bh(&bc_lock);
 779         return TIPC_OK;
 780 }
 781
 782 int tipc_bclink_init(void)
 783 {
 784         bcbearer = kmalloc(sizeof(*bcbearer), GFP_ATOMIC);
 785         bclink = kmalloc(sizeof(*bclink), GFP_ATOMIC);
 786         if (!bcbearer || !bclink) {
 787  nomem:
 788                 warn("Memory squeeze; Failed to create multicast link\n");
 789                 kfree(bcbearer);
 790                 bcbearer = NULL;
 791                 kfree(bclink);
 792                 bclink = NULL;
 793                 return -ENOMEM;
 794         }
 795
 796         memset(bcbearer, 0, sizeof(struct bcbearer));
 797         INIT_LIST_HEAD(&bcbearer->bearer.cong_links);
 798         bcbearer->bearer.media = &bcbearer->media;
 799         bcbearer->media.send_msg = tipc_bcbearer_send;
 800         sprintf(bcbearer->media.name, "tipc-multicast");
 801
 802         bcl = &bclink->link;
 803         memset(bclink, 0, sizeof(struct bclink));
 804         INIT_LIST_HEAD(&bcl->waiting_ports);
 805         bcl->next_out_no = 1;
 806         bclink->node.lock =  SPIN_LOCK_UNLOCKED;
 807         bcl->owner = &bclink->node;
 808         bcl->max_pkt = MAX_PKT_DEFAULT_MCAST;
 809         tipc_link_set_queue_limits(bcl, BCLINK_WIN_DEFAULT);
 810         bcl->b_ptr = &bcbearer->bearer;
 811         bcl->state = WORKING_WORKING;
 812         sprintf(bcl->name, tipc_bclink_name);
 813
 814         if (BCLINK_LOG_BUF_SIZE) {
 815                 char *pb = kmalloc(BCLINK_LOG_BUF_SIZE, GFP_ATOMIC);
 816
 817                 if (!pb)
 818                         goto nomem;
 819                 tipc_printbuf_init(&bcl->print_buf, pb, BCLINK_LOG_BUF_SIZE);
 820         }
 821
 822         return TIPC_OK;
 823 }
 824
 825 void tipc_bclink_stop(void)
 826 {
 827         spin_lock_bh(&bc_lock);
 828         if (bcbearer) {
 829                 tipc_link_stop(bcl);
 830                 if (BCLINK_LOG_BUF_SIZE)
 831                         kfree(bcl->print_buf.buf);
 832                 bcl = NULL;
 833                 kfree(bclink);
 834                 bclink = NULL;
 835                 kfree(bcbearer);
 836                 bcbearer = NULL;
 837         }
 838         spin_unlock_bh(&bc_lock);
 839 }
 840