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