net/tipc/bcast.c

   1 /*
   2  * net/tipc/bcast.c: TIPC broadcast code
   3  *
   4  * Copyright (c) 2004-2006, Ericsson AB
   5  * Copyright (c) 2004, Intel Corporation.
   6  * Copyright (c) 2005, 2010-2011, Wind River Systems
   7  * All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions are met:
  11  *
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. Neither the names of the copyright holders nor the names of its
  18  *    contributors may be used to endorse or promote products derived from
  19  *    this software without specific prior written permission.
  20  *
  21  * Alternatively, this software may be distributed under the terms of the
  22  * GNU General Public License ("GPL") version 2 as published by the Free
  23  * Software Foundation.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  26  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  28  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  29  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  35  * POSSIBILITY OF SUCH DAMAGE.
  36  */
  37
  38 #include "core.h"
  39 #include "link.h"
  40 #include "port.h"
  41 #include "bcast.h"
  42 #include "name_distr.h"
  43
  44 #define MAX_PKT_DEFAULT_MCAST 1500      /* bcast link max packet size (fixed) */
  45
  46 #define BCLINK_WIN_DEFAULT 20           /* bcast link window size (default) */
  47
  48 /**
  49  * struct tipc_bcbearer_pair - a pair of bearers used by broadcast link
  50  * @primary: pointer to primary bearer
  51  * @secondary: pointer to secondary bearer
  52  *
  53  * Bearers must have same priority and same set of reachable destinations
  54  * to be paired.
  55  */
  56
  57 struct tipc_bcbearer_pair {
  58         struct tipc_bearer *primary;
  59         struct tipc_bearer *secondary;
  60 };
  61
  62 /**
  63  * struct tipc_bcbearer - bearer used by broadcast link
  64  * @bearer: (non-standard) broadcast bearer structure
  65  * @media: (non-standard) broadcast media structure
  66  * @bpairs: array of bearer pairs
  67  * @bpairs_temp: temporary array of bearer pairs used by tipc_bcbearer_sort()
  68  * @remains: temporary node map used by tipc_bcbearer_send()
  69  * @remains_new: temporary node map used tipc_bcbearer_send()
  70  *
  71  * Note: The fields labelled "temporary" are incorporated into the bearer
  72  * to avoid consuming potentially limited stack space through the use of
  73  * large local variables within multicast routines.  Concurrent access is
  74  * prevented through use of the spinlock "bc_lock".
  75  */
  76
  77 struct tipc_bcbearer {
  78         struct tipc_bearer bearer;
  79         struct tipc_media media;
  80         struct tipc_bcbearer_pair bpairs[MAX_BEARERS];
  81         struct tipc_bcbearer_pair bpairs_temp[TIPC_MAX_LINK_PRI + 1];
  82         struct tipc_node_map remains;
  83         struct tipc_node_map remains_new;
  84 };
  85
  86 /**
  87  * struct tipc_bclink - link used for broadcast messages
  88  * @link: (non-standard) broadcast link structure
  89  * @node: (non-standard) node structure representing b'cast link's peer node
  90  * @bcast_nodes: map of broadcast-capable nodes
  91  * @retransmit_to: node that most recently requested a retransmit
  92  *
  93  * Handles sequence numbering, fragmentation, bundling, etc.
  94  */
  95
  96 struct tipc_bclink {
  97         struct tipc_link link;
  98         struct tipc_node node;
  99         struct tipc_node_map bcast_nodes;
 100         struct tipc_node *retransmit_to;
 101 };
 102
 103 static struct tipc_bcbearer bcast_bearer;
 104 static struct tipc_bclink bcast_link;
 105
 106 static struct tipc_bcbearer *bcbearer = &bcast_bearer;
 107 static struct tipc_bclink *bclink = &bcast_link;
 108 static struct tipc_link *bcl = &bcast_link.link;
 109
 110 static DEFINE_SPINLOCK(bc_lock);
 111
 112 const char tipc_bclink_name[] = "broadcast-link";
 113
 114 static void tipc_nmap_diff(struct tipc_node_map *nm_a,
 115                            struct tipc_node_map *nm_b,
 116                            struct tipc_node_map *nm_diff);
 117
 118 static u32 bcbuf_acks(struct sk_buff *buf)
 119 {
 120         return (u32)(unsigned long)TIPC_SKB_CB(buf)->handle;
 121 }
 122
 123 static void bcbuf_set_acks(struct sk_buff *buf, u32 acks)
 124 {
 125         TIPC_SKB_CB(buf)->handle = (void *)(unsigned long)acks;
 126 }
 127
 128 static void bcbuf_decr_acks(struct sk_buff *buf)
 129 {
 130         bcbuf_set_acks(buf, bcbuf_acks(buf) - 1);
 131 }
 132
 133 void tipc_bclink_add_node(u32 addr)
 134 {
 135         spin_lock_bh(&bc_lock);
 136         tipc_nmap_add(&bclink->bcast_nodes, addr);
 137         spin_unlock_bh(&bc_lock);
 138 }
 139
 140 void tipc_bclink_remove_node(u32 addr)
 141 {
 142         spin_lock_bh(&bc_lock);
 143         tipc_nmap_remove(&bclink->bcast_nodes, addr);
 144         spin_unlock_bh(&bc_lock);
 145 }
 146
 147 static void bclink_set_last_sent(void)
 148 {
 149         if (bcl->next_out)
 150                 bcl->fsm_msg_cnt = mod(buf_seqno(bcl->next_out) - 1);
 151         else
 152                 bcl->fsm_msg_cnt = mod(bcl->next_out_no - 1);
 153 }
 154
 155 u32 tipc_bclink_get_last_sent(void)
 156 {
 157         return bcl->fsm_msg_cnt;
 158 }
 159
 160 static void bclink_update_last_sent(struct tipc_node *node, u32 seqno)
 161 {
 162         node->bclink.last_sent = less_eq(node->bclink.last_sent, seqno) ?
 163                                                 seqno : node->bclink.last_sent;
 164 }
 165
 166
 167 /*
 168  * tipc_bclink_retransmit_to - get most recent node to request retransmission
 169  *
 170  * Called with bc_lock locked
 171  */
 172
 173 struct tipc_node *tipc_bclink_retransmit_to(void)
 174 {
 175         return bclink->retransmit_to;
 176 }
 177
 178 /**
 179  * bclink_retransmit_pkt - retransmit broadcast packets
 180  * @after: sequence number of last packet to *not* retransmit
 181  * @to: sequence number of last packet to retransmit
 182  *
 183  * Called with bc_lock locked
 184  */
 185
 186 static void bclink_retransmit_pkt(u32 after, u32 to)
 187 {
 188         struct sk_buff *buf;
 189
 190         buf = bcl->first_out;
 191         while (buf && less_eq(buf_seqno(buf), after))
 192                 buf = buf->next;
 193         tipc_link_retransmit(bcl, buf, mod(to - after));
 194 }
 195
 196 /**
 197  * tipc_bclink_acknowledge - handle acknowledgement of broadcast packets
 198  * @n_ptr: node that sent acknowledgement info
 199  * @acked: broadcast sequence # that has been acknowledged
 200  *
 201  * Node is locked, bc_lock unlocked.
 202  */
 203
 204 void tipc_bclink_acknowledge(struct tipc_node *n_ptr, u32 acked)
 205 {
 206         struct sk_buff *crs;
 207         struct sk_buff *next;
 208         unsigned int released = 0;
 209
 210         spin_lock_bh(&bc_lock);
 211
 212         /* Bail out if tx queue is empty (no clean up is required) */
 213         crs = bcl->first_out;
 214         if (!crs)
 215                 goto exit;
 216
 217         /* Determine which messages need to be acknowledged */
 218         if (acked == INVALID_LINK_SEQ) {
 219                 /*
 220                  * Contact with specified node has been lost, so need to
 221                  * acknowledge sent messages only (if other nodes still exist)
 222                  * or both sent and unsent messages (otherwise)
 223                  */
 224                 if (bclink->bcast_nodes.count)
 225                         acked = bcl->fsm_msg_cnt;
 226                 else
 227                         acked = bcl->next_out_no;
 228         } else {
 229                 /*
 230                  * Bail out if specified sequence number does not correspond
 231                  * to a message that has been sent and not yet acknowledged
 232                  */
 233                 if (less(acked, buf_seqno(crs)) ||
 234                     less(bcl->fsm_msg_cnt, acked) ||
 235                     less_eq(acked, n_ptr->bclink.acked))
 236                         goto exit;
 237         }
 238
 239         /* Skip over packets that node has previously acknowledged */
 240         while (crs && less_eq(buf_seqno(crs), n_ptr->bclink.acked))
 241                 crs = crs->next;
 242
 243         /* Update packets that node is now acknowledging */
 244
 245         while (crs && less_eq(buf_seqno(crs), acked)) {
 246                 next = crs->next;
 247
 248                 if (crs != bcl->next_out)
 249                         bcbuf_decr_acks(crs);
 250                 else {
 251                         bcbuf_set_acks(crs, 0);
 252                         bcl->next_out = next;
 253                         bclink_set_last_sent();
 254                 }
 255
 256                 if (bcbuf_acks(crs) == 0) {
 257                         bcl->first_out = next;
 258                         bcl->out_queue_size--;
 259                         kfree_skb(crs);
 260                         released = 1;
 261                 }
 262                 crs = next;
 263         }
 264         n_ptr->bclink.acked = acked;
 265
 266         /* Try resolving broadcast link congestion, if necessary */
 267
 268         if (unlikely(bcl->next_out)) {
 269                 tipc_link_push_queue(bcl);
 270                 bclink_set_last_sent();
 271         }
 272         if (unlikely(released && !list_empty(&bcl->waiting_ports)))
 273                 tipc_link_wakeup_ports(bcl, 0);
 274 exit:
 275         spin_unlock_bh(&bc_lock);
 276 }
 277
 278 /*
 279  * tipc_bclink_update_link_state - update broadcast link state
 280  *
 281  * tipc_net_lock and node lock set
 282  */
 283
 284 void tipc_bclink_update_link_state(struct tipc_node *n_ptr, u32 last_sent)
 285 {
 286         struct sk_buff *buf;
 287
 288         /* Ignore "stale" link state info */
 289
 290         if (less_eq(last_sent, n_ptr->bclink.last_in))
 291                 return;
 292
 293         /* Update link synchronization state; quit if in sync */
 294
 295         bclink_update_last_sent(n_ptr, last_sent);
 296
 297         if (n_ptr->bclink.last_sent == n_ptr->bclink.last_in)
 298                 return;
 299
 300         /* Update out-of-sync state; quit if loss is still unconfirmed */
 301
 302         if ((++n_ptr->bclink.oos_state) == 1) {
 303                 if (n_ptr->bclink.deferred_size < (TIPC_MIN_LINK_WIN / 2))
 304                         return;
 305                 n_ptr->bclink.oos_state++;
 306         }
 307
 308         /* Don't NACK if one has been recently sent (or seen) */
 309
 310         if (n_ptr->bclink.oos_state & 0x1)
 311                 return;
 312
 313         /* Send NACK */
 314
 315         buf = tipc_buf_acquire(INT_H_SIZE);
 316         if (buf) {
 317                 struct tipc_msg *msg = buf_msg(buf);
 318
 319                 tipc_msg_init(msg, BCAST_PROTOCOL, STATE_MSG,
 320                               INT_H_SIZE, n_ptr->addr);
 321                 msg_set_non_seq(msg, 1);
 322                 msg_set_mc_netid(msg, tipc_net_id);
 323                 msg_set_bcast_ack(msg, n_ptr->bclink.last_in);
 324                 msg_set_bcgap_after(msg, n_ptr->bclink.last_in);
 325                 msg_set_bcgap_to(msg, n_ptr->bclink.deferred_head
 326                                  ? buf_seqno(n_ptr->bclink.deferred_head) - 1
 327                                  : n_ptr->bclink.last_sent);
 328
 329                 spin_lock_bh(&bc_lock);
 330                 tipc_bearer_send(&bcbearer->bearer, buf, NULL);
 331                 bcl->stats.sent_nacks++;
 332                 spin_unlock_bh(&bc_lock);
 333                 kfree_skb(buf);
 334
 335                 n_ptr->bclink.oos_state++;
 336         }
 337 }
 338
 339 /*
 340  * bclink_peek_nack - monitor retransmission requests sent by other nodes
 341  *
 342  * Delay any upcoming NACK by this node if another node has already
 343  * requested the first message this node is going to ask for.
 344  *
 345  * Only tipc_net_lock set.
 346  */
 347
 348 static void bclink_peek_nack(struct tipc_msg *msg)
 349 {
 350         struct tipc_node *n_ptr = tipc_node_find(msg_destnode(msg));
 351
 352         if (unlikely(!n_ptr))
 353                 return;
 354
 355         tipc_node_lock(n_ptr);
 356
 357         if (n_ptr->bclink.supported &&
 358             (n_ptr->bclink.last_in != n_ptr->bclink.last_sent) &&
 359             (n_ptr->bclink.last_in == msg_bcgap_after(msg)))
 360                 n_ptr->bclink.oos_state = 2;
 361
 362         tipc_node_unlock(n_ptr);
 363 }
 364
 365 /*
 366  * tipc_bclink_send_msg - broadcast a packet to all nodes in cluster
 367  */
 368
 369 int tipc_bclink_send_msg(struct sk_buff *buf)
 370 {
 371         int res;
 372
 373         spin_lock_bh(&bc_lock);
 374
 375         if (!bclink->bcast_nodes.count) {
 376                 res = msg_data_sz(buf_msg(buf));
 377                 kfree_skb(buf);
 378                 goto exit;
 379         }
 380
 381         res = tipc_link_send_buf(bcl, buf);
 382         if (likely(res >= 0)) {
 383                 bclink_set_last_sent();
 384                 bcl->stats.queue_sz_counts++;
 385                 bcl->stats.accu_queue_sz += bcl->out_queue_size;
 386         }
 387 exit:
 388         spin_unlock_bh(&bc_lock);
 389         return res;
 390 }
 391
 392 /*
 393  * bclink_accept_pkt - accept an incoming, in-sequence broadcast packet
 394  *
 395  * Called with both sending node's lock and bc_lock taken.
 396  */
 397
 398 static void bclink_accept_pkt(struct tipc_node *node, u32 seqno)
 399 {
 400         bclink_update_last_sent(node, seqno);
 401         node->bclink.last_in = seqno;
 402         node->bclink.oos_state = 0;
 403         bcl->stats.recv_info++;
 404
 405         /*
 406          * Unicast an ACK periodically, ensuring that
 407          * all nodes in the cluster don't ACK at the same time
 408          */
 409
 410         if (((seqno - tipc_own_addr) % TIPC_MIN_LINK_WIN) == 0) {
 411                 tipc_link_send_proto_msg(
 412                         node->active_links[node->addr & 1],
 413                         STATE_MSG, 0, 0, 0, 0, 0);
 414                 bcl->stats.sent_acks++;
 415         }
 416 }
 417
 418 /*
 419  * tipc_bclink_recv_pkt - receive a broadcast packet, and deliver upwards
 420  *
 421  * tipc_net_lock is read_locked, no other locks set
 422  */
 423
 424 void tipc_bclink_recv_pkt(struct sk_buff *buf)
 425 {
 426         struct tipc_msg *msg = buf_msg(buf);
 427         struct tipc_node *node;
 428         u32 next_in;
 429         u32 seqno;
 430         int deferred;
 431
 432         /* Screen out unwanted broadcast messages */
 433
 434         if (msg_mc_netid(msg) != tipc_net_id)
 435                 goto exit;
 436
 437         node = tipc_node_find(msg_prevnode(msg));
 438         if (unlikely(!node))
 439                 goto exit;
 440
 441         tipc_node_lock(node);
 442         if (unlikely(!node->bclink.supported))
 443                 goto unlock;
 444
 445         /* Handle broadcast protocol message */
 446
 447         if (unlikely(msg_user(msg) == BCAST_PROTOCOL)) {
 448                 if (msg_type(msg) != STATE_MSG)
 449                         goto unlock;
 450                 if (msg_destnode(msg) == tipc_own_addr) {
 451                         tipc_bclink_acknowledge(node, msg_bcast_ack(msg));
 452                         tipc_node_unlock(node);
 453                         spin_lock_bh(&bc_lock);
 454                         bcl->stats.recv_nacks++;
 455                         bclink->retransmit_to = node;
 456                         bclink_retransmit_pkt(msg_bcgap_after(msg),
 457                                               msg_bcgap_to(msg));
 458                         spin_unlock_bh(&bc_lock);
 459                 } else {
 460                         tipc_node_unlock(node);
 461                         bclink_peek_nack(msg);
 462                 }
 463                 goto exit;
 464         }
 465
 466         /* Handle in-sequence broadcast message */
 467
 468         seqno = msg_seqno(msg);
 469         next_in = mod(node->bclink.last_in + 1);
 470
 471         if (likely(seqno == next_in)) {
 472 receive:
 473                 /* Deliver message to destination */
 474
 475                 if (likely(msg_isdata(msg))) {
 476                         spin_lock_bh(&bc_lock);
 477                         bclink_accept_pkt(node, seqno);
 478                         spin_unlock_bh(&bc_lock);
 479                         tipc_node_unlock(node);
 480                         if (likely(msg_mcast(msg)))
 481                                 tipc_port_recv_mcast(buf, NULL);
 482                         else
 483                                 kfree_skb(buf);
 484                 } else if (msg_user(msg) == MSG_BUNDLER) {
 485                         spin_lock_bh(&bc_lock);
 486                         bclink_accept_pkt(node, seqno);
 487                         bcl->stats.recv_bundles++;
 488                         bcl->stats.recv_bundled += msg_msgcnt(msg);
 489                         spin_unlock_bh(&bc_lock);
 490                         tipc_node_unlock(node);
 491                         tipc_link_recv_bundle(buf);
 492                 } else if (msg_user(msg) == MSG_FRAGMENTER) {
 493                         int ret = tipc_link_recv_fragment(&node->bclink.defragm,
 494                                                       &buf, &msg);
 495                         if (ret < 0)
 496                                 goto unlock;
 497                         spin_lock_bh(&bc_lock);
 498                         bclink_accept_pkt(node, seqno);
 499                         bcl->stats.recv_fragments++;
 500                         if (ret > 0)
 501                                 bcl->stats.recv_fragmented++;
 502                         spin_unlock_bh(&bc_lock);
 503                         tipc_node_unlock(node);
 504                         tipc_net_route_msg(buf);
 505                 } else if (msg_user(msg) == NAME_DISTRIBUTOR) {
 506                         spin_lock_bh(&bc_lock);
 507                         bclink_accept_pkt(node, seqno);
 508                         spin_unlock_bh(&bc_lock);
 509                         tipc_node_unlock(node);
 510                         tipc_named_recv(buf);
 511                 } else {
 512                         spin_lock_bh(&bc_lock);
 513                         bclink_accept_pkt(node, seqno);
 514                         spin_unlock_bh(&bc_lock);
 515                         tipc_node_unlock(node);
 516                         kfree_skb(buf);
 517                 }
 518                 buf = NULL;
 519
 520                 /* Determine new synchronization state */
 521
 522                 tipc_node_lock(node);
 523                 if (unlikely(!tipc_node_is_up(node)))
 524                         goto unlock;
 525
 526                 if (node->bclink.last_in == node->bclink.last_sent)
 527                         goto unlock;
 528
 529                 if (!node->bclink.deferred_head) {
 530                         node->bclink.oos_state = 1;
 531                         goto unlock;
 532                 }
 533
 534                 msg = buf_msg(node->bclink.deferred_head);
 535                 seqno = msg_seqno(msg);
 536                 next_in = mod(next_in + 1);
 537                 if (seqno != next_in)
 538                         goto unlock;
 539
 540                 /* Take in-sequence message from deferred queue & deliver it */
 541
 542                 buf = node->bclink.deferred_head;
 543                 node->bclink.deferred_head = buf->next;
 544                 node->bclink.deferred_size--;
 545                 goto receive;
 546         }
 547
 548         /* Handle out-of-sequence broadcast message */
 549
 550         if (less(next_in, seqno)) {
 551                 deferred = tipc_link_defer_pkt(&node->bclink.deferred_head,
 552                                                &node->bclink.deferred_tail,
 553                                                buf);
 554                 node->bclink.deferred_size += deferred;
 555                 bclink_update_last_sent(node, seqno);
 556                 buf = NULL;
 557         } else
 558                 deferred = 0;
 559
 560         spin_lock_bh(&bc_lock);
 561
 562         if (deferred)
 563                 bcl->stats.deferred_recv++;
 564         else
 565                 bcl->stats.duplicates++;
 566
 567         spin_unlock_bh(&bc_lock);
 568
 569 unlock:
 570         tipc_node_unlock(node);
 571 exit:
 572         kfree_skb(buf);
 573 }
 574
 575 u32 tipc_bclink_acks_missing(struct tipc_node *n_ptr)
 576 {
 577         return (n_ptr->bclink.supported &&
 578                 (tipc_bclink_get_last_sent() != n_ptr->bclink.acked));
 579 }
 580
 581
 582 /**
 583  * tipc_bcbearer_send - send a packet through the broadcast pseudo-bearer
 584  *
 585  * Send packet over as many bearers as necessary to reach all nodes
 586  * that have joined the broadcast link.
 587  *
 588  * Returns 0 (packet sent successfully) under all circumstances,
 589  * since the broadcast link's pseudo-bearer never blocks
 590  */
 591
 592 static int tipc_bcbearer_send(struct sk_buff *buf,
 593                               struct tipc_bearer *unused1,
 594                               struct tipc_media_addr *unused2)
 595 {
 596         int bp_index;
 597
 598         /*
 599          * Prepare broadcast link message for reliable transmission,
 600          * if first time trying to send it;
 601          * preparation is skipped for broadcast link protocol messages
 602          * since they are sent in an unreliable manner and don't need it
 603          */
 604
 605         if (likely(!msg_non_seq(buf_msg(buf)))) {
 606                 struct tipc_msg *msg;
 607
 608                 bcbuf_set_acks(buf, bclink->bcast_nodes.count);
 609                 msg = buf_msg(buf);
 610                 msg_set_non_seq(msg, 1);
 611                 msg_set_mc_netid(msg, tipc_net_id);
 612                 bcl->stats.sent_info++;
 613
 614                 if (WARN_ON(!bclink->bcast_nodes.count)) {
 615                         dump_stack();
 616                         return 0;
 617                 }
 618         }
 619
 620         /* Send buffer over bearers until all targets reached */
 621
 622         bcbearer->remains = bclink->bcast_nodes;
 623
 624         for (bp_index = 0; bp_index < MAX_BEARERS; bp_index++) {
 625                 struct tipc_bearer *p = bcbearer->bpairs[bp_index].primary;
 626                 struct tipc_bearer *s = bcbearer->bpairs[bp_index].secondary;
 627
 628                 if (!p)
 629                         break;  /* no more bearers to try */
 630
 631                 tipc_nmap_diff(&bcbearer->remains, &p->nodes, &bcbearer->remains_new);
 632                 if (bcbearer->remains_new.count == bcbearer->remains.count)
 633                         continue;       /* bearer pair doesn't add anything */
 634
 635                 if (p->blocked ||
 636                     p->media->send_msg(buf, p, &p->media->bcast_addr)) {
 637                         /* unable to send on primary bearer */
 638                         if (!s || s->blocked ||
 639                             s->media->send_msg(buf, s,
 640                                                &s->media->bcast_addr)) {
 641                                 /* unable to send on either bearer */
 642                                 continue;
 643                         }
 644                 }
 645
 646                 if (s) {
 647                         bcbearer->bpairs[bp_index].primary = s;
 648                         bcbearer->bpairs[bp_index].secondary = p;
 649                 }
 650
 651                 if (bcbearer->remains_new.count == 0)
 652                         break;  /* all targets reached */
 653
 654                 bcbearer->remains = bcbearer->remains_new;
 655         }
 656
 657         return 0;
 658 }
 659
 660 /**
 661  * tipc_bcbearer_sort - create sets of bearer pairs used by broadcast bearer
 662  */
 663
 664 void tipc_bcbearer_sort(void)
 665 {
 666         struct tipc_bcbearer_pair *bp_temp = bcbearer->bpairs_temp;
 667         struct tipc_bcbearer_pair *bp_curr;
 668         int b_index;
 669         int pri;
 670
 671         spin_lock_bh(&bc_lock);
 672
 673         /* Group bearers by priority (can assume max of two per priority) */
 674
 675         memset(bp_temp, 0, sizeof(bcbearer->bpairs_temp));
 676
 677         for (b_index = 0; b_index < MAX_BEARERS; b_index++) {
 678                 struct tipc_bearer *b = &tipc_bearers[b_index];
 679
 680                 if (!b->active || !b->nodes.count)
 681                         continue;
 682
 683                 if (!bp_temp[b->priority].primary)
 684                         bp_temp[b->priority].primary = b;
 685                 else
 686                         bp_temp[b->priority].secondary = b;
 687         }
 688
 689         /* Create array of bearer pairs for broadcasting */
 690
 691         bp_curr = bcbearer->bpairs;
 692         memset(bcbearer->bpairs, 0, sizeof(bcbearer->bpairs));
 693
 694         for (pri = TIPC_MAX_LINK_PRI; pri >= 0; pri--) {
 695
 696                 if (!bp_temp[pri].primary)
 697                         continue;
 698
 699                 bp_curr->primary = bp_temp[pri].primary;
 700
 701                 if (bp_temp[pri].secondary) {
 702                         if (tipc_nmap_equal(&bp_temp[pri].primary->nodes,
 703                                             &bp_temp[pri].secondary->nodes)) {
 704                                 bp_curr->secondary = bp_temp[pri].secondary;
 705                         } else {
 706                                 bp_curr++;
 707                                 bp_curr->primary = bp_temp[pri].secondary;
 708                         }
 709                 }
 710
 711                 bp_curr++;
 712         }
 713
 714         spin_unlock_bh(&bc_lock);
 715 }
 716
 717
 718 int tipc_bclink_stats(char *buf, const u32 buf_size)
 719 {
 720         struct print_buf pb;
 721
 722         if (!bcl)
 723                 return 0;
 724
 725         tipc_printbuf_init(&pb, buf, buf_size);
 726
 727         spin_lock_bh(&bc_lock);
 728
 729         tipc_printf(&pb, "Link <%s>\n"
 730                          "  Window:%u packets\n",
 731                     bcl->name, bcl->queue_limit[0]);
 732         tipc_printf(&pb, "  RX packets:%u fragments:%u/%u bundles:%u/%u\n",
 733                     bcl->stats.recv_info,
 734                     bcl->stats.recv_fragments,
 735                     bcl->stats.recv_fragmented,
 736                     bcl->stats.recv_bundles,
 737                     bcl->stats.recv_bundled);
 738         tipc_printf(&pb, "  TX packets:%u fragments:%u/%u bundles:%u/%u\n",
 739                     bcl->stats.sent_info,
 740                     bcl->stats.sent_fragments,
 741                     bcl->stats.sent_fragmented,
 742                     bcl->stats.sent_bundles,
 743                     bcl->stats.sent_bundled);
 744         tipc_printf(&pb, "  RX naks:%u defs:%u dups:%u\n",
 745                     bcl->stats.recv_nacks,
 746                     bcl->stats.deferred_recv,
 747                     bcl->stats.duplicates);
 748         tipc_printf(&pb, "  TX naks:%u acks:%u dups:%u\n",
 749                     bcl->stats.sent_nacks,
 750                     bcl->stats.sent_acks,
 751                     bcl->stats.retransmitted);
 752         tipc_printf(&pb, "  Congestion bearer:%u link:%u  Send queue max:%u avg:%u\n",
 753                     bcl->stats.bearer_congs,
 754                     bcl->stats.link_congs,
 755                     bcl->stats.max_queue_sz,
 756                     bcl->stats.queue_sz_counts
 757                     ? (bcl->stats.accu_queue_sz / bcl->stats.queue_sz_counts)
 758                     : 0);
 759
 760         spin_unlock_bh(&bc_lock);
 761         return tipc_printbuf_validate(&pb);
 762 }
 763
 764 int tipc_bclink_reset_stats(void)
 765 {
 766         if (!bcl)
 767                 return -ENOPROTOOPT;
 768
 769         spin_lock_bh(&bc_lock);
 770         memset(&bcl->stats, 0, sizeof(bcl->stats));
 771         spin_unlock_bh(&bc_lock);
 772         return 0;
 773 }
 774
 775 int tipc_bclink_set_queue_limits(u32 limit)
 776 {
 777         if (!bcl)
 778                 return -ENOPROTOOPT;
 779         if ((limit < TIPC_MIN_LINK_WIN) || (limit > TIPC_MAX_LINK_WIN))
 780                 return -EINVAL;
 781
 782         spin_lock_bh(&bc_lock);
 783         tipc_link_set_queue_limits(bcl, limit);
 784         spin_unlock_bh(&bc_lock);
 785         return 0;
 786 }
 787
 788 void tipc_bclink_init(void)
 789 {
 790         INIT_LIST_HEAD(&bcbearer->bearer.cong_links);
 791         bcbearer->bearer.media = &bcbearer->media;
 792         bcbearer->media.send_msg = tipc_bcbearer_send;
 793         sprintf(bcbearer->media.name, "tipc-broadcast");
 794
 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         strlcpy(bcl->name, tipc_bclink_name, TIPC_MAX_LINK_NAME);
 804 }
 805
 806 void tipc_bclink_stop(void)
 807 {
 808         spin_lock_bh(&bc_lock);
 809         tipc_link_stop(bcl);
 810         spin_unlock_bh(&bc_lock);
 811
 812         memset(bclink, 0, sizeof(*bclink));
 813         memset(bcbearer, 0, sizeof(*bcbearer));
 814 }
 815
 816
 817 /**
 818  * tipc_nmap_add - add a node to a node map
 819  */
 820
 821 void tipc_nmap_add(struct tipc_node_map *nm_ptr, u32 node)
 822 {
 823         int n = tipc_node(node);
 824         int w = n / WSIZE;
 825         u32 mask = (1 << (n % WSIZE));
 826
 827         if ((nm_ptr->map[w] & mask) == 0) {
 828                 nm_ptr->count++;
 829                 nm_ptr->map[w] |= mask;
 830         }
 831 }
 832
 833 /**
 834  * tipc_nmap_remove - remove a node from a node map
 835  */
 836
 837 void tipc_nmap_remove(struct tipc_node_map *nm_ptr, u32 node)
 838 {
 839         int n = tipc_node(node);
 840         int w = n / WSIZE;
 841         u32 mask = (1 << (n % WSIZE));
 842
 843         if ((nm_ptr->map[w] & mask) != 0) {
 844                 nm_ptr->map[w] &= ~mask;
 845                 nm_ptr->count--;
 846         }
 847 }
 848
 849 /**
 850  * tipc_nmap_diff - find differences between node maps
 851  * @nm_a: input node map A
 852  * @nm_b: input node map B
 853  * @nm_diff: output node map A-B (i.e. nodes of A that are not in B)
 854  */
 855
 856 static void tipc_nmap_diff(struct tipc_node_map *nm_a,
 857                            struct tipc_node_map *nm_b,
 858                            struct tipc_node_map *nm_diff)
 859 {
 860         int stop = ARRAY_SIZE(nm_a->map);
 861         int w;
 862         int b;
 863         u32 map;
 864
 865         memset(nm_diff, 0, sizeof(*nm_diff));
 866         for (w = 0; w < stop; w++) {
 867                 map = nm_a->map[w] ^ (nm_a->map[w] & nm_b->map[w]);
 868                 nm_diff->map[w] = map;
 869                 if (map != 0) {
 870                         for (b = 0 ; b < WSIZE; b++) {
 871                                 if (map & (1 << b))
 872                                         nm_diff->count++;
 873                         }
 874                 }
 875         }
 876 }
 877
 878 /**
 879  * tipc_port_list_add - add a port to a port list, ensuring no duplicates
 880  */
 881
 882 void tipc_port_list_add(struct tipc_port_list *pl_ptr, u32 port)
 883 {
 884         struct tipc_port_list *item = pl_ptr;
 885         int i;
 886         int item_sz = PLSIZE;
 887         int cnt = pl_ptr->count;
 888
 889         for (; ; cnt -= item_sz, item = item->next) {
 890                 if (cnt < PLSIZE)
 891                         item_sz = cnt;
 892                 for (i = 0; i < item_sz; i++)
 893                         if (item->ports[i] == port)
 894                                 return;
 895                 if (i < PLSIZE) {
 896                         item->ports[i] = port;
 897                         pl_ptr->count++;
 898                         return;
 899                 }
 900                 if (!item->next) {
 901                         item->next = kmalloc(sizeof(*item), GFP_ATOMIC);
 902                         if (!item->next) {
 903                                 warn("Incomplete multicast delivery, no memory\n");
 904                                 return;
 905                         }
 906                         item->next->next = NULL;
 907                 }
 908         }
 909 }
 910
 911 /**
 912  * tipc_port_list_free - free dynamically created entries in port_list chain
 913  *
 914  */
 915
 916 void tipc_port_list_free(struct tipc_port_list *pl_ptr)
 917 {
 918         struct tipc_port_list *item;
 919         struct tipc_port_list *next;
 920
 921         for (item = pl_ptr->next; item; item = next) {
 922                 next = item->next;
 923                 kfree(item);
 924         }
 925 }
 926