linux/net/tipc/bcast.c
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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, 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
  57struct 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
  77struct 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
  96struct 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
 103static struct tipc_bcbearer bcast_bearer;
 104static struct tipc_bclink bcast_link;
 105
 106static struct tipc_bcbearer *bcbearer = &bcast_bearer;
 107static struct tipc_bclink *bclink = &bcast_link;
 108static struct tipc_link *bcl = &bcast_link.link;
 109
 110static DEFINE_SPINLOCK(bc_lock);
 111
 112const char tipc_bclink_name[] = "broadcast-link";
 113
 114static 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
 118static u32 bcbuf_acks(struct sk_buff *buf)
 119{
 120        return (u32)(unsigned long)TIPC_SKB_CB(buf)->handle;
 121}
 122
 123static void bcbuf_set_acks(struct sk_buff *buf, u32 acks)
 124{
 125        TIPC_SKB_CB(buf)->handle = (void *)(unsigned long)acks;
 126}
 127
 128static void bcbuf_decr_acks(struct sk_buff *buf)
 129{
 130        bcbuf_set_acks(buf, bcbuf_acks(buf) - 1);
 131}
 132
 133void 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
 140void 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
 147static 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
 155u32 tipc_bclink_get_last_sent(void)
 156{
 157        return bcl->fsm_msg_cnt;
 158}
 159
 160/**
 161 * bclink_set_gap - set gap according to contents of current deferred pkt queue
 162 *
 163 * Called with 'node' locked, bc_lock unlocked
 164 */
 165
 166static void bclink_set_gap(struct tipc_node *n_ptr)
 167{
 168        struct sk_buff *buf = n_ptr->bclink.deferred_head;
 169
 170        n_ptr->bclink.gap_after = n_ptr->bclink.gap_to =
 171                mod(n_ptr->bclink.last_in);
 172        if (unlikely(buf != NULL))
 173                n_ptr->bclink.gap_to = mod(buf_seqno(buf) - 1);
 174}
 175
 176/**
 177 * bclink_ack_allowed - test if ACK or NACK message can be sent at this moment
 178 *
 179 * This mechanism endeavours to prevent all nodes in network from trying
 180 * to ACK or NACK at the same time.
 181 *
 182 * Note: TIPC uses a different trigger to distribute ACKs than it does to
 183 *       distribute NACKs, but tries to use the same spacing (divide by 16).
 184 */
 185
 186static int bclink_ack_allowed(u32 n)
 187{
 188        return (n % TIPC_MIN_LINK_WIN) == tipc_own_tag;
 189}
 190
 191
 192/**
 193 * tipc_bclink_retransmit_to - get most recent node to request retransmission
 194 *
 195 * Called with bc_lock locked
 196 */
 197
 198struct tipc_node *tipc_bclink_retransmit_to(void)
 199{
 200        return bclink->retransmit_to;
 201}
 202
 203/**
 204 * bclink_retransmit_pkt - retransmit broadcast packets
 205 * @after: sequence number of last packet to *not* retransmit
 206 * @to: sequence number of last packet to retransmit
 207 *
 208 * Called with bc_lock locked
 209 */
 210
 211static void bclink_retransmit_pkt(u32 after, u32 to)
 212{
 213        struct sk_buff *buf;
 214
 215        buf = bcl->first_out;
 216        while (buf && less_eq(buf_seqno(buf), after))
 217                buf = buf->next;
 218        tipc_link_retransmit(bcl, buf, mod(to - after));
 219}
 220
 221/**
 222 * tipc_bclink_acknowledge - handle acknowledgement of broadcast packets
 223 * @n_ptr: node that sent acknowledgement info
 224 * @acked: broadcast sequence # that has been acknowledged
 225 *
 226 * Node is locked, bc_lock unlocked.
 227 */
 228
 229void tipc_bclink_acknowledge(struct tipc_node *n_ptr, u32 acked)
 230{
 231        struct sk_buff *crs;
 232        struct sk_buff *next;
 233        unsigned int released = 0;
 234
 235        spin_lock_bh(&bc_lock);
 236
 237        /* Bail out if tx queue is empty (no clean up is required) */
 238        crs = bcl->first_out;
 239        if (!crs)
 240                goto exit;
 241
 242        /* Determine which messages need to be acknowledged */
 243        if (acked == INVALID_LINK_SEQ) {
 244                /*
 245                 * Contact with specified node has been lost, so need to
 246                 * acknowledge sent messages only (if other nodes still exist)
 247                 * or both sent and unsent messages (otherwise)
 248                 */
 249                if (bclink->bcast_nodes.count)
 250                        acked = bcl->fsm_msg_cnt;
 251                else
 252                        acked = bcl->next_out_no;
 253        } else {
 254                /*
 255                 * Bail out if specified sequence number does not correspond
 256                 * to a message that has been sent and not yet acknowledged
 257                 */
 258                if (less(acked, buf_seqno(crs)) ||
 259                    less(bcl->fsm_msg_cnt, acked) ||
 260                    less_eq(acked, n_ptr->bclink.acked))
 261                        goto exit;
 262        }
 263
 264        /* Skip over packets that node has previously acknowledged */
 265        while (crs && less_eq(buf_seqno(crs), n_ptr->bclink.acked))
 266                crs = crs->next;
 267
 268        /* Update packets that node is now acknowledging */
 269
 270        while (crs && less_eq(buf_seqno(crs), acked)) {
 271                next = crs->next;
 272
 273                if (crs != bcl->next_out)
 274                        bcbuf_decr_acks(crs);
 275                else {
 276                        bcbuf_set_acks(crs, 0);
 277                        bcl->next_out = next;
 278                        bclink_set_last_sent();
 279                }
 280
 281                if (bcbuf_acks(crs) == 0) {
 282                        bcl->first_out = next;
 283                        bcl->out_queue_size--;
 284                        buf_discard(crs);
 285                        released = 1;
 286                }
 287                crs = next;
 288        }
 289        n_ptr->bclink.acked = acked;
 290
 291        /* Try resolving broadcast link congestion, if necessary */
 292
 293        if (unlikely(bcl->next_out)) {
 294                tipc_link_push_queue(bcl);
 295                bclink_set_last_sent();
 296        }
 297        if (unlikely(released && !list_empty(&bcl->waiting_ports)))
 298                tipc_link_wakeup_ports(bcl, 0);
 299exit:
 300        spin_unlock_bh(&bc_lock);
 301}
 302
 303/**
 304 * bclink_send_ack - unicast an ACK msg
 305 *
 306 * tipc_net_lock and node lock set
 307 */
 308
 309static void bclink_send_ack(struct tipc_node *n_ptr)
 310{
 311        struct tipc_link *l_ptr = n_ptr->active_links[n_ptr->addr & 1];
 312
 313        if (l_ptr != NULL)
 314                tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
 315}
 316
 317/**
 318 * bclink_send_nack- broadcast a NACK msg
 319 *
 320 * tipc_net_lock and node lock set
 321 */
 322
 323static void bclink_send_nack(struct tipc_node *n_ptr)
 324{
 325        struct sk_buff *buf;
 326        struct tipc_msg *msg;
 327
 328        if (!less(n_ptr->bclink.gap_after, n_ptr->bclink.gap_to))
 329                return;
 330
 331        buf = tipc_buf_acquire(INT_H_SIZE);
 332        if (buf) {
 333                msg = buf_msg(buf);
 334                tipc_msg_init(msg, BCAST_PROTOCOL, STATE_MSG,
 335                         INT_H_SIZE, n_ptr->addr);
 336                msg_set_non_seq(msg, 1);
 337                msg_set_mc_netid(msg, tipc_net_id);
 338                msg_set_bcast_ack(msg, mod(n_ptr->bclink.last_in));
 339                msg_set_bcgap_after(msg, n_ptr->bclink.gap_after);
 340                msg_set_bcgap_to(msg, n_ptr->bclink.gap_to);
 341                msg_set_bcast_tag(msg, tipc_own_tag);
 342
 343                tipc_bearer_send(&bcbearer->bearer, buf, NULL);
 344                bcl->stats.sent_nacks++;
 345                buf_discard(buf);
 346
 347                /*
 348                 * Ensure we doesn't send another NACK msg to the node
 349                 * until 16 more deferred messages arrive from it
 350                 * (i.e. helps prevent all nodes from NACK'ing at same time)
 351                 */
 352
 353                n_ptr->bclink.nack_sync = tipc_own_tag;
 354        }
 355}
 356
 357/**
 358 * tipc_bclink_check_gap - send a NACK if a sequence gap exists
 359 *
 360 * tipc_net_lock and node lock set
 361 */
 362
 363void tipc_bclink_check_gap(struct tipc_node *n_ptr, u32 last_sent)
 364{
 365        if (!n_ptr->bclink.supported ||
 366            less_eq(last_sent, mod(n_ptr->bclink.last_in)))
 367                return;
 368
 369        bclink_set_gap(n_ptr);
 370        if (n_ptr->bclink.gap_after == n_ptr->bclink.gap_to)
 371                n_ptr->bclink.gap_to = last_sent;
 372        bclink_send_nack(n_ptr);
 373}
 374
 375/**
 376 * tipc_bclink_peek_nack - process a NACK msg meant for another node
 377 *
 378 * Only tipc_net_lock set.
 379 */
 380
 381static void tipc_bclink_peek_nack(u32 dest, u32 sender_tag, u32 gap_after, u32 gap_to)
 382{
 383        struct tipc_node *n_ptr = tipc_node_find(dest);
 384        u32 my_after, my_to;
 385
 386        if (unlikely(!n_ptr || !tipc_node_is_up(n_ptr)))
 387                return;
 388        tipc_node_lock(n_ptr);
 389        /*
 390         * Modify gap to suppress unnecessary NACKs from this node
 391         */
 392        my_after = n_ptr->bclink.gap_after;
 393        my_to = n_ptr->bclink.gap_to;
 394
 395        if (less_eq(gap_after, my_after)) {
 396                if (less(my_after, gap_to) && less(gap_to, my_to))
 397                        n_ptr->bclink.gap_after = gap_to;
 398                else if (less_eq(my_to, gap_to))
 399                        n_ptr->bclink.gap_to = n_ptr->bclink.gap_after;
 400        } else if (less_eq(gap_after, my_to)) {
 401                if (less_eq(my_to, gap_to))
 402                        n_ptr->bclink.gap_to = gap_after;
 403        } else {
 404                /*
 405                 * Expand gap if missing bufs not in deferred queue:
 406                 */
 407                struct sk_buff *buf = n_ptr->bclink.deferred_head;
 408                u32 prev = n_ptr->bclink.gap_to;
 409
 410                for (; buf; buf = buf->next) {
 411                        u32 seqno = buf_seqno(buf);
 412
 413                        if (mod(seqno - prev) != 1) {
 414                                buf = NULL;
 415                                break;
 416                        }
 417                        if (seqno == gap_after)
 418                                break;
 419                        prev = seqno;
 420                }
 421                if (buf == NULL)
 422                        n_ptr->bclink.gap_to = gap_after;
 423        }
 424        /*
 425         * Some nodes may send a complementary NACK now:
 426         */
 427        if (bclink_ack_allowed(sender_tag + 1)) {
 428                if (n_ptr->bclink.gap_to != n_ptr->bclink.gap_after) {
 429                        bclink_send_nack(n_ptr);
 430                        bclink_set_gap(n_ptr);
 431                }
 432        }
 433        tipc_node_unlock(n_ptr);
 434}
 435
 436/**
 437 * tipc_bclink_send_msg - broadcast a packet to all nodes in cluster
 438 */
 439
 440int tipc_bclink_send_msg(struct sk_buff *buf)
 441{
 442        int res;
 443
 444        spin_lock_bh(&bc_lock);
 445
 446        if (!bclink->bcast_nodes.count) {
 447                res = msg_data_sz(buf_msg(buf));
 448                buf_discard(buf);
 449                goto exit;
 450        }
 451
 452        res = tipc_link_send_buf(bcl, buf);
 453        if (likely(res >= 0)) {
 454                bclink_set_last_sent();
 455                bcl->stats.queue_sz_counts++;
 456                bcl->stats.accu_queue_sz += bcl->out_queue_size;
 457        }
 458exit:
 459        spin_unlock_bh(&bc_lock);
 460        return res;
 461}
 462
 463/**
 464 * tipc_bclink_recv_pkt - receive a broadcast packet, and deliver upwards
 465 *
 466 * tipc_net_lock is read_locked, no other locks set
 467 */
 468
 469void tipc_bclink_recv_pkt(struct sk_buff *buf)
 470{
 471        struct tipc_msg *msg = buf_msg(buf);
 472        struct tipc_node *node;
 473        u32 next_in;
 474        u32 seqno;
 475        struct sk_buff *deferred;
 476
 477        /* Screen out unwanted broadcast messages */
 478
 479        if (msg_mc_netid(msg) != tipc_net_id)
 480                goto exit;
 481
 482        node = tipc_node_find(msg_prevnode(msg));
 483        if (unlikely(!node))
 484                goto exit;
 485
 486        tipc_node_lock(node);
 487        if (unlikely(!node->bclink.supported))
 488                goto unlock;
 489
 490        if (unlikely(msg_user(msg) == BCAST_PROTOCOL)) {
 491                if (msg_type(msg) != STATE_MSG)
 492                        goto unlock;
 493                if (msg_destnode(msg) == tipc_own_addr) {
 494                        tipc_bclink_acknowledge(node, msg_bcast_ack(msg));
 495                        tipc_node_unlock(node);
 496                        spin_lock_bh(&bc_lock);
 497                        bcl->stats.recv_nacks++;
 498                        bclink->retransmit_to = node;
 499                        bclink_retransmit_pkt(msg_bcgap_after(msg),
 500                                              msg_bcgap_to(msg));
 501                        spin_unlock_bh(&bc_lock);
 502                } else {
 503                        tipc_node_unlock(node);
 504                        tipc_bclink_peek_nack(msg_destnode(msg),
 505                                              msg_bcast_tag(msg),
 506                                              msg_bcgap_after(msg),
 507                                              msg_bcgap_to(msg));
 508                }
 509                goto exit;
 510        }
 511
 512        /* Handle in-sequence broadcast message */
 513
 514receive:
 515        next_in = mod(node->bclink.last_in + 1);
 516        seqno = msg_seqno(msg);
 517
 518        if (likely(seqno == next_in)) {
 519                bcl->stats.recv_info++;
 520                node->bclink.last_in++;
 521                bclink_set_gap(node);
 522                if (unlikely(bclink_ack_allowed(seqno))) {
 523                        bclink_send_ack(node);
 524                        bcl->stats.sent_acks++;
 525                }
 526                if (likely(msg_isdata(msg))) {
 527                        tipc_node_unlock(node);
 528                        if (likely(msg_mcast(msg)))
 529                                tipc_port_recv_mcast(buf, NULL);
 530                        else
 531                                buf_discard(buf);
 532                } else if (msg_user(msg) == MSG_BUNDLER) {
 533                        bcl->stats.recv_bundles++;
 534                        bcl->stats.recv_bundled += msg_msgcnt(msg);
 535                        tipc_node_unlock(node);
 536                        tipc_link_recv_bundle(buf);
 537                } else if (msg_user(msg) == MSG_FRAGMENTER) {
 538                        bcl->stats.recv_fragments++;
 539                        if (tipc_link_recv_fragment(&node->bclink.defragm,
 540                                                    &buf, &msg))
 541                                bcl->stats.recv_fragmented++;
 542                        tipc_node_unlock(node);
 543                        tipc_net_route_msg(buf);
 544                } else if (msg_user(msg) == NAME_DISTRIBUTOR) {
 545                        tipc_node_unlock(node);
 546                        tipc_named_recv(buf);
 547                } else {
 548                        tipc_node_unlock(node);
 549                        buf_discard(buf);
 550                }
 551                buf = NULL;
 552                tipc_node_lock(node);
 553                deferred = node->bclink.deferred_head;
 554                if (deferred && (buf_seqno(deferred) == mod(next_in + 1))) {
 555                        buf = deferred;
 556                        msg = buf_msg(buf);
 557                        node->bclink.deferred_head = deferred->next;
 558                        goto receive;
 559                }
 560        } else if (less(next_in, seqno)) {
 561                u32 gap_after = node->bclink.gap_after;
 562                u32 gap_to = node->bclink.gap_to;
 563
 564                if (tipc_link_defer_pkt(&node->bclink.deferred_head,
 565                                        &node->bclink.deferred_tail,
 566                                        buf)) {
 567                        node->bclink.nack_sync++;
 568                        bcl->stats.deferred_recv++;
 569                        if (seqno == mod(gap_after + 1))
 570                                node->bclink.gap_after = seqno;
 571                        else if (less(gap_after, seqno) && less(seqno, gap_to))
 572                                node->bclink.gap_to = seqno;
 573                }
 574                buf = NULL;
 575                if (bclink_ack_allowed(node->bclink.nack_sync)) {
 576                        if (gap_to != gap_after)
 577                                bclink_send_nack(node);
 578                        bclink_set_gap(node);
 579                }
 580        } else {
 581                bcl->stats.duplicates++;
 582        }
 583unlock:
 584        tipc_node_unlock(node);
 585exit:
 586        buf_discard(buf);
 587}
 588
 589u32 tipc_bclink_acks_missing(struct tipc_node *n_ptr)
 590{
 591        return (n_ptr->bclink.supported &&
 592                (tipc_bclink_get_last_sent() != n_ptr->bclink.acked));
 593}
 594
 595
 596/**
 597 * tipc_bcbearer_send - send a packet through the broadcast pseudo-bearer
 598 *
 599 * Send packet over as many bearers as necessary to reach all nodes
 600 * that have joined the broadcast link.
 601 *
 602 * Returns 0 (packet sent successfully) under all circumstances,
 603 * since the broadcast link's pseudo-bearer never blocks
 604 */
 605
 606static int tipc_bcbearer_send(struct sk_buff *buf,
 607                              struct tipc_bearer *unused1,
 608                              struct tipc_media_addr *unused2)
 609{
 610        int bp_index;
 611
 612        /*
 613         * Prepare broadcast link message for reliable transmission,
 614         * if first time trying to send it;
 615         * preparation is skipped for broadcast link protocol messages
 616         * since they are sent in an unreliable manner and don't need it
 617         */
 618
 619        if (likely(!msg_non_seq(buf_msg(buf)))) {
 620                struct tipc_msg *msg;
 621
 622                bcbuf_set_acks(buf, bclink->bcast_nodes.count);
 623                msg = buf_msg(buf);
 624                msg_set_non_seq(msg, 1);
 625                msg_set_mc_netid(msg, tipc_net_id);
 626                bcl->stats.sent_info++;
 627
 628                if (WARN_ON(!bclink->bcast_nodes.count)) {
 629                        dump_stack();
 630                        return 0;
 631                }
 632        }
 633
 634        /* Send buffer over bearers until all targets reached */
 635
 636        bcbearer->remains = bclink->bcast_nodes;
 637
 638        for (bp_index = 0; bp_index < MAX_BEARERS; bp_index++) {
 639                struct tipc_bearer *p = bcbearer->bpairs[bp_index].primary;
 640                struct tipc_bearer *s = bcbearer->bpairs[bp_index].secondary;
 641
 642                if (!p)
 643                        break;  /* no more bearers to try */
 644
 645                tipc_nmap_diff(&bcbearer->remains, &p->nodes, &bcbearer->remains_new);
 646                if (bcbearer->remains_new.count == bcbearer->remains.count)
 647                        continue;       /* bearer pair doesn't add anything */
 648
 649                if (p->blocked ||
 650                    p->media->send_msg(buf, p, &p->media->bcast_addr)) {
 651                        /* unable to send on primary bearer */
 652                        if (!s || s->blocked ||
 653                            s->media->send_msg(buf, s,
 654                                               &s->media->bcast_addr)) {
 655                                /* unable to send on either bearer */
 656                                continue;
 657                        }
 658                }
 659
 660                if (s) {
 661                        bcbearer->bpairs[bp_index].primary = s;
 662                        bcbearer->bpairs[bp_index].secondary = p;
 663                }
 664
 665                if (bcbearer->remains_new.count == 0)
 666                        break;  /* all targets reached */
 667
 668                bcbearer->remains = bcbearer->remains_new;
 669        }
 670
 671        return 0;
 672}
 673
 674/**
 675 * tipc_bcbearer_sort - create sets of bearer pairs used by broadcast bearer
 676 */
 677
 678void tipc_bcbearer_sort(void)
 679{
 680        struct tipc_bcbearer_pair *bp_temp = bcbearer->bpairs_temp;
 681        struct tipc_bcbearer_pair *bp_curr;
 682        int b_index;
 683        int pri;
 684
 685        spin_lock_bh(&bc_lock);
 686
 687        /* Group bearers by priority (can assume max of two per priority) */
 688
 689        memset(bp_temp, 0, sizeof(bcbearer->bpairs_temp));
 690
 691        for (b_index = 0; b_index < MAX_BEARERS; b_index++) {
 692                struct tipc_bearer *b = &tipc_bearers[b_index];
 693
 694                if (!b->active || !b->nodes.count)
 695                        continue;
 696
 697                if (!bp_temp[b->priority].primary)
 698                        bp_temp[b->priority].primary = b;
 699                else
 700                        bp_temp[b->priority].secondary = b;
 701        }
 702
 703        /* Create array of bearer pairs for broadcasting */
 704
 705        bp_curr = bcbearer->bpairs;
 706        memset(bcbearer->bpairs, 0, sizeof(bcbearer->bpairs));
 707
 708        for (pri = TIPC_MAX_LINK_PRI; pri >= 0; pri--) {
 709
 710                if (!bp_temp[pri].primary)
 711                        continue;
 712
 713                bp_curr->primary = bp_temp[pri].primary;
 714
 715                if (bp_temp[pri].secondary) {
 716                        if (tipc_nmap_equal(&bp_temp[pri].primary->nodes,
 717                                            &bp_temp[pri].secondary->nodes)) {
 718                                bp_curr->secondary = bp_temp[pri].secondary;
 719                        } else {
 720                                bp_curr++;
 721                                bp_curr->primary = bp_temp[pri].secondary;
 722                        }
 723                }
 724
 725                bp_curr++;
 726        }
 727
 728        spin_unlock_bh(&bc_lock);
 729}
 730
 731
 732int tipc_bclink_stats(char *buf, const u32 buf_size)
 733{
 734        struct print_buf pb;
 735
 736        if (!bcl)
 737                return 0;
 738
 739        tipc_printbuf_init(&pb, buf, buf_size);
 740
 741        spin_lock_bh(&bc_lock);
 742
 743        tipc_printf(&pb, "Link <%s>\n"
 744                         "  Window:%u packets\n",
 745                    bcl->name, bcl->queue_limit[0]);
 746        tipc_printf(&pb, "  RX packets:%u fragments:%u/%u bundles:%u/%u\n",
 747                    bcl->stats.recv_info,
 748                    bcl->stats.recv_fragments,
 749                    bcl->stats.recv_fragmented,
 750                    bcl->stats.recv_bundles,
 751                    bcl->stats.recv_bundled);
 752        tipc_printf(&pb, "  TX packets:%u fragments:%u/%u bundles:%u/%u\n",
 753                    bcl->stats.sent_info,
 754                    bcl->stats.sent_fragments,
 755                    bcl->stats.sent_fragmented,
 756                    bcl->stats.sent_bundles,
 757                    bcl->stats.sent_bundled);
 758        tipc_printf(&pb, "  RX naks:%u defs:%u dups:%u\n",
 759                    bcl->stats.recv_nacks,
 760                    bcl->stats.deferred_recv,
 761                    bcl->stats.duplicates);
 762        tipc_printf(&pb, "  TX naks:%u acks:%u dups:%u\n",
 763                    bcl->stats.sent_nacks,
 764                    bcl->stats.sent_acks,
 765                    bcl->stats.retransmitted);
 766        tipc_printf(&pb, "  Congestion bearer:%u link:%u  Send queue max:%u avg:%u\n",
 767                    bcl->stats.bearer_congs,
 768                    bcl->stats.link_congs,
 769                    bcl->stats.max_queue_sz,
 770                    bcl->stats.queue_sz_counts
 771                    ? (bcl->stats.accu_queue_sz / bcl->stats.queue_sz_counts)
 772                    : 0);
 773
 774        spin_unlock_bh(&bc_lock);
 775        return tipc_printbuf_validate(&pb);
 776}
 777
 778int tipc_bclink_reset_stats(void)
 779{
 780        if (!bcl)
 781                return -ENOPROTOOPT;
 782
 783        spin_lock_bh(&bc_lock);
 784        memset(&bcl->stats, 0, sizeof(bcl->stats));
 785        spin_unlock_bh(&bc_lock);
 786        return 0;
 787}
 788
 789int tipc_bclink_set_queue_limits(u32 limit)
 790{
 791        if (!bcl)
 792                return -ENOPROTOOPT;
 793        if ((limit < TIPC_MIN_LINK_WIN) || (limit > TIPC_MAX_LINK_WIN))
 794                return -EINVAL;
 795
 796        spin_lock_bh(&bc_lock);
 797        tipc_link_set_queue_limits(bcl, limit);
 798        spin_unlock_bh(&bc_lock);
 799        return 0;
 800}
 801
 802void tipc_bclink_init(void)
 803{
 804        INIT_LIST_HEAD(&bcbearer->bearer.cong_links);
 805        bcbearer->bearer.media = &bcbearer->media;
 806        bcbearer->media.send_msg = tipc_bcbearer_send;
 807        sprintf(bcbearer->media.name, "tipc-broadcast");
 808
 809        INIT_LIST_HEAD(&bcl->waiting_ports);
 810        bcl->next_out_no = 1;
 811        spin_lock_init(&bclink->node.lock);
 812        bcl->owner = &bclink->node;
 813        bcl->max_pkt = MAX_PKT_DEFAULT_MCAST;
 814        tipc_link_set_queue_limits(bcl, BCLINK_WIN_DEFAULT);
 815        bcl->b_ptr = &bcbearer->bearer;
 816        bcl->state = WORKING_WORKING;
 817        strlcpy(bcl->name, tipc_bclink_name, TIPC_MAX_LINK_NAME);
 818}
 819
 820void tipc_bclink_stop(void)
 821{
 822        spin_lock_bh(&bc_lock);
 823        tipc_link_stop(bcl);
 824        spin_unlock_bh(&bc_lock);
 825
 826        memset(bclink, 0, sizeof(*bclink));
 827        memset(bcbearer, 0, sizeof(*bcbearer));
 828}
 829
 830
 831/**
 832 * tipc_nmap_add - add a node to a node map
 833 */
 834
 835void tipc_nmap_add(struct tipc_node_map *nm_ptr, u32 node)
 836{
 837        int n = tipc_node(node);
 838        int w = n / WSIZE;
 839        u32 mask = (1 << (n % WSIZE));
 840
 841        if ((nm_ptr->map[w] & mask) == 0) {
 842                nm_ptr->count++;
 843                nm_ptr->map[w] |= mask;
 844        }
 845}
 846
 847/**
 848 * tipc_nmap_remove - remove a node from a node map
 849 */
 850
 851void tipc_nmap_remove(struct tipc_node_map *nm_ptr, u32 node)
 852{
 853        int n = tipc_node(node);
 854        int w = n / WSIZE;
 855        u32 mask = (1 << (n % WSIZE));
 856
 857        if ((nm_ptr->map[w] & mask) != 0) {
 858                nm_ptr->map[w] &= ~mask;
 859                nm_ptr->count--;
 860        }
 861}
 862
 863/**
 864 * tipc_nmap_diff - find differences between node maps
 865 * @nm_a: input node map A
 866 * @nm_b: input node map B
 867 * @nm_diff: output node map A-B (i.e. nodes of A that are not in B)
 868 */
 869
 870static void tipc_nmap_diff(struct tipc_node_map *nm_a,
 871                           struct tipc_node_map *nm_b,
 872                           struct tipc_node_map *nm_diff)
 873{
 874        int stop = ARRAY_SIZE(nm_a->map);
 875        int w;
 876        int b;
 877        u32 map;
 878
 879        memset(nm_diff, 0, sizeof(*nm_diff));
 880        for (w = 0; w < stop; w++) {
 881                map = nm_a->map[w] ^ (nm_a->map[w] & nm_b->map[w]);
 882                nm_diff->map[w] = map;
 883                if (map != 0) {
 884                        for (b = 0 ; b < WSIZE; b++) {
 885                                if (map & (1 << b))
 886                                        nm_diff->count++;
 887                        }
 888                }
 889        }
 890}
 891
 892/**
 893 * tipc_port_list_add - add a port to a port list, ensuring no duplicates
 894 */
 895
 896void tipc_port_list_add(struct tipc_port_list *pl_ptr, u32 port)
 897{
 898        struct tipc_port_list *item = pl_ptr;
 899        int i;
 900        int item_sz = PLSIZE;
 901        int cnt = pl_ptr->count;
 902
 903        for (; ; cnt -= item_sz, item = item->next) {
 904                if (cnt < PLSIZE)
 905                        item_sz = cnt;
 906                for (i = 0; i < item_sz; i++)
 907                        if (item->ports[i] == port)
 908                                return;
 909                if (i < PLSIZE) {
 910                        item->ports[i] = port;
 911                        pl_ptr->count++;
 912                        return;
 913                }
 914                if (!item->next) {
 915                        item->next = kmalloc(sizeof(*item), GFP_ATOMIC);
 916                        if (!item->next) {
 917                                warn("Incomplete multicast delivery, no memory\n");
 918                                return;
 919                        }
 920                        item->next->next = NULL;
 921                }
 922        }
 923}
 924
 925/**
 926 * tipc_port_list_free - free dynamically created entries in port_list chain
 927 *
 928 */
 929
 930void tipc_port_list_free(struct tipc_port_list *pl_ptr)
 931{
 932        struct tipc_port_list *item;
 933        struct tipc_port_list *next;
 934
 935        for (item = pl_ptr->next; item; item = next) {
 936                next = item->next;
 937                kfree(item);
 938        }
 939}
 940
 941