net/tipc/bcast.c

   1 /*
   2  * net/tipc/bcast.c: TIPC broadcast code
   3  *
   4  * Copyright (c) 2004-2006, 2014-2017, 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 <linux/tipc_config.h>
  39 #include "socket.h"
  40 #include "msg.h"
  41 #include "bcast.h"
  42 #include "link.h"
  43 #include "name_table.h"
  44
  45 #define BCLINK_WIN_DEFAULT  50  /* bcast link window size (default) */
  46 #define BCLINK_WIN_MIN      32  /* bcast minimum link window size */
  47
  48 const char tipc_bclink_name[] = "broadcast-link";
  49 unsigned long sysctl_tipc_bc_retruni __read_mostly;
  50
  51 /**
  52  * struct tipc_bc_base - base structure for keeping broadcast send state
  53  * @link: broadcast send link structure
  54  * @inputq: data input queue; will only carry SOCK_WAKEUP messages
  55  * @dests: array keeping number of reachable destinations per bearer
  56  * @primary_bearer: a bearer having links to all broadcast destinations, if any
  57  * @bcast_support: indicates if primary bearer, if any, supports broadcast
  58  * @force_bcast: forces broadcast for multicast traffic
  59  * @rcast_support: indicates if all peer nodes support replicast
  60  * @force_rcast: forces replicast for multicast traffic
  61  * @rc_ratio: dest count as percentage of cluster size where send method changes
  62  * @bc_threshold: calculated from rc_ratio; if dests > threshold use broadcast
  63  */
  64 struct tipc_bc_base {
  65         struct tipc_link *link;
  66         struct sk_buff_head inputq;
  67         int dests[MAX_BEARERS];
  68         int primary_bearer;
  69         bool bcast_support;
  70         bool force_bcast;
  71         bool rcast_support;
  72         bool force_rcast;
  73         int rc_ratio;
  74         int bc_threshold;
  75 };
  76
  77 static struct tipc_bc_base *tipc_bc_base(struct net *net)
  78 {
  79         return tipc_net(net)->bcbase;
  80 }
  81
  82 /* tipc_bcast_get_mtu(): -get the MTU currently used by broadcast link
  83  * Note: the MTU is decremented to give room for a tunnel header, in
  84  * case the message needs to be sent as replicast
  85  */
  86 int tipc_bcast_get_mtu(struct net *net)
  87 {
  88         return tipc_link_mss(tipc_bc_sndlink(net));
  89 }
  90
  91 void tipc_bcast_toggle_rcast(struct net *net, bool supp)
  92 {
  93         tipc_bc_base(net)->rcast_support = supp;
  94 }
  95
  96 static void tipc_bcbase_calc_bc_threshold(struct net *net)
  97 {
  98         struct tipc_bc_base *bb = tipc_bc_base(net);
  99         int cluster_size = tipc_link_bc_peers(tipc_bc_sndlink(net));
 100
 101         bb->bc_threshold = 1 + (cluster_size * bb->rc_ratio / 100);
 102 }
 103
 104 /* tipc_bcbase_select_primary(): find a bearer with links to all destinations,
 105  *                               if any, and make it primary bearer
 106  */
 107 static void tipc_bcbase_select_primary(struct net *net)
 108 {
 109         struct tipc_bc_base *bb = tipc_bc_base(net);
 110         int all_dests =  tipc_link_bc_peers(bb->link);
 111         int max_win = tipc_link_max_win(bb->link);
 112         int min_win = tipc_link_min_win(bb->link);
 113         int i, mtu, prim;
 114
 115         bb->primary_bearer = INVALID_BEARER_ID;
 116         bb->bcast_support = true;
 117
 118         if (!all_dests)
 119                 return;
 120
 121         for (i = 0; i < MAX_BEARERS; i++) {
 122                 if (!bb->dests[i])
 123                         continue;
 124
 125                 mtu = tipc_bearer_mtu(net, i);
 126                 if (mtu < tipc_link_mtu(bb->link)) {
 127                         tipc_link_set_mtu(bb->link, mtu);
 128                         tipc_link_set_queue_limits(bb->link,
 129                                                    min_win,
 130                                                    max_win);
 131                 }
 132                 bb->bcast_support &= tipc_bearer_bcast_support(net, i);
 133                 if (bb->dests[i] < all_dests)
 134                         continue;
 135
 136                 bb->primary_bearer = i;
 137
 138                 /* Reduce risk that all nodes select same primary */
 139                 if ((i ^ tipc_own_addr(net)) & 1)
 140                         break;
 141         }
 142         prim = bb->primary_bearer;
 143         if (prim != INVALID_BEARER_ID)
 144                 bb->bcast_support = tipc_bearer_bcast_support(net, prim);
 145 }
 146
 147 void tipc_bcast_inc_bearer_dst_cnt(struct net *net, int bearer_id)
 148 {
 149         struct tipc_bc_base *bb = tipc_bc_base(net);
 150
 151         tipc_bcast_lock(net);
 152         bb->dests[bearer_id]++;
 153         tipc_bcbase_select_primary(net);
 154         tipc_bcast_unlock(net);
 155 }
 156
 157 void tipc_bcast_dec_bearer_dst_cnt(struct net *net, int bearer_id)
 158 {
 159         struct tipc_bc_base *bb = tipc_bc_base(net);
 160
 161         tipc_bcast_lock(net);
 162         bb->dests[bearer_id]--;
 163         tipc_bcbase_select_primary(net);
 164         tipc_bcast_unlock(net);
 165 }
 166
 167 /* tipc_bcbase_xmit - broadcast a packet queue across one or more bearers
 168  *
 169  * Note that number of reachable destinations, as indicated in the dests[]
 170  * array, may transitionally differ from the number of destinations indicated
 171  * in each sent buffer. We can sustain this. Excess destination nodes will
 172  * drop and never acknowledge the unexpected packets, and missing destinations
 173  * will either require retransmission (if they are just about to be added to
 174  * the bearer), or be removed from the buffer's 'ackers' counter (if they
 175  * just went down)
 176  */
 177 static void tipc_bcbase_xmit(struct net *net, struct sk_buff_head *xmitq)
 178 {
 179         int bearer_id;
 180         struct tipc_bc_base *bb = tipc_bc_base(net);
 181         struct sk_buff *skb, *_skb;
 182         struct sk_buff_head _xmitq;
 183
 184         if (skb_queue_empty(xmitq))
 185                 return;
 186
 187         /* The typical case: at least one bearer has links to all nodes */
 188         bearer_id = bb->primary_bearer;
 189         if (bearer_id >= 0) {
 190                 tipc_bearer_bc_xmit(net, bearer_id, xmitq);
 191                 return;
 192         }
 193
 194         /* We have to transmit across all bearers */
 195         __skb_queue_head_init(&_xmitq);
 196         for (bearer_id = 0; bearer_id < MAX_BEARERS; bearer_id++) {
 197                 if (!bb->dests[bearer_id])
 198                         continue;
 199
 200                 skb_queue_walk(xmitq, skb) {
 201                         _skb = pskb_copy_for_clone(skb, GFP_ATOMIC);
 202                         if (!_skb)
 203                                 break;
 204                         __skb_queue_tail(&_xmitq, _skb);
 205                 }
 206                 tipc_bearer_bc_xmit(net, bearer_id, &_xmitq);
 207         }
 208         __skb_queue_purge(xmitq);
 209         __skb_queue_purge(&_xmitq);
 210 }
 211
 212 static void tipc_bcast_select_xmit_method(struct net *net, int dests,
 213                                           struct tipc_mc_method *method)
 214 {
 215         struct tipc_bc_base *bb = tipc_bc_base(net);
 216         unsigned long exp = method->expires;
 217
 218         /* Broadcast supported by used bearer/bearers? */
 219         if (!bb->bcast_support) {
 220                 method->rcast = true;
 221                 return;
 222         }
 223         /* Any destinations which don't support replicast ? */
 224         if (!bb->rcast_support) {
 225                 method->rcast = false;
 226                 return;
 227         }
 228         /* Can current method be changed ? */
 229         method->expires = jiffies + TIPC_METHOD_EXPIRE;
 230         if (method->mandatory)
 231                 return;
 232
 233         if (!(tipc_net(net)->capabilities & TIPC_MCAST_RBCTL) &&
 234             time_before(jiffies, exp))
 235                 return;
 236
 237         /* Configuration as force 'broadcast' method */
 238         if (bb->force_bcast) {
 239                 method->rcast = false;
 240                 return;
 241         }
 242         /* Configuration as force 'replicast' method */
 243         if (bb->force_rcast) {
 244                 method->rcast = true;
 245                 return;
 246         }
 247         /* Configuration as 'autoselect' or default method */
 248         /* Determine method to use now */
 249         method->rcast = dests <= bb->bc_threshold;
 250 }
 251
 252 /* tipc_bcast_xmit - broadcast the buffer chain to all external nodes
 253  * @net: the applicable net namespace
 254  * @pkts: chain of buffers containing message
 255  * @cong_link_cnt: set to 1 if broadcast link is congested, otherwise 0
 256  * Consumes the buffer chain.
 257  * Returns 0 if success, otherwise errno: -EHOSTUNREACH,-EMSGSIZE
 258  */
 259 int tipc_bcast_xmit(struct net *net, struct sk_buff_head *pkts,
 260                     u16 *cong_link_cnt)
 261 {
 262         struct tipc_link *l = tipc_bc_sndlink(net);
 263         struct sk_buff_head xmitq;
 264         int rc = 0;
 265
 266         __skb_queue_head_init(&xmitq);
 267         tipc_bcast_lock(net);
 268         if (tipc_link_bc_peers(l))
 269                 rc = tipc_link_xmit(l, pkts, &xmitq);
 270         tipc_bcast_unlock(net);
 271         tipc_bcbase_xmit(net, &xmitq);
 272         __skb_queue_purge(pkts);
 273         if (rc == -ELINKCONG) {
 274                 *cong_link_cnt = 1;
 275                 rc = 0;
 276         }
 277         return rc;
 278 }
 279
 280 /* tipc_rcast_xmit - replicate and send a message to given destination nodes
 281  * @net: the applicable net namespace
 282  * @pkts: chain of buffers containing message
 283  * @dests: list of destination nodes
 284  * @cong_link_cnt: returns number of congested links
 285  * @cong_links: returns identities of congested links
 286  * Returns 0 if success, otherwise errno
 287  */
 288 static int tipc_rcast_xmit(struct net *net, struct sk_buff_head *pkts,
 289                            struct tipc_nlist *dests, u16 *cong_link_cnt)
 290 {
 291         struct tipc_dest *dst, *tmp;
 292         struct sk_buff_head _pkts;
 293         u32 dnode, selector;
 294
 295         selector = msg_link_selector(buf_msg(skb_peek(pkts)));
 296         __skb_queue_head_init(&_pkts);
 297
 298         list_for_each_entry_safe(dst, tmp, &dests->list, list) {
 299                 dnode = dst->node;
 300                 if (!tipc_msg_pskb_copy(dnode, pkts, &_pkts))
 301                         return -ENOMEM;
 302
 303                 /* Any other return value than -ELINKCONG is ignored */
 304                 if (tipc_node_xmit(net, &_pkts, dnode, selector) == -ELINKCONG)
 305                         (*cong_link_cnt)++;
 306         }
 307         return 0;
 308 }
 309
 310 /* tipc_mcast_send_sync - deliver a dummy message with SYN bit
 311  * @net: the applicable net namespace
 312  * @skb: socket buffer to copy
 313  * @method: send method to be used
 314  * @dests: destination nodes for message.
 315  * Returns 0 if success, otherwise errno
 316  */
 317 static int tipc_mcast_send_sync(struct net *net, struct sk_buff *skb,
 318                                 struct tipc_mc_method *method,
 319                                 struct tipc_nlist *dests)
 320 {
 321         struct tipc_msg *hdr, *_hdr;
 322         struct sk_buff_head tmpq;
 323         struct sk_buff *_skb;
 324         u16 cong_link_cnt;
 325         int rc = 0;
 326
 327         /* Is a cluster supporting with new capabilities ? */
 328         if (!(tipc_net(net)->capabilities & TIPC_MCAST_RBCTL))
 329                 return 0;
 330
 331         hdr = buf_msg(skb);
 332         if (msg_user(hdr) == MSG_FRAGMENTER)
 333                 hdr = msg_inner_hdr(hdr);
 334         if (msg_type(hdr) != TIPC_MCAST_MSG)
 335                 return 0;
 336
 337         /* Allocate dummy message */
 338         _skb = tipc_buf_acquire(MCAST_H_SIZE, GFP_KERNEL);
 339         if (!_skb)
 340                 return -ENOMEM;
 341
 342         /* Preparing for 'synching' header */
 343         msg_set_syn(hdr, 1);
 344
 345         /* Copy skb's header into a dummy header */
 346         skb_copy_to_linear_data(_skb, hdr, MCAST_H_SIZE);
 347         skb_orphan(_skb);
 348
 349         /* Reverse method for dummy message */
 350         _hdr = buf_msg(_skb);
 351         msg_set_size(_hdr, MCAST_H_SIZE);
 352         msg_set_is_rcast(_hdr, !msg_is_rcast(hdr));
 353         msg_set_errcode(_hdr, TIPC_ERR_NO_PORT);
 354
 355         __skb_queue_head_init(&tmpq);
 356         __skb_queue_tail(&tmpq, _skb);
 357         if (method->rcast)
 358                 rc = tipc_bcast_xmit(net, &tmpq, &cong_link_cnt);
 359         else
 360                 rc = tipc_rcast_xmit(net, &tmpq, dests, &cong_link_cnt);
 361
 362         /* This queue should normally be empty by now */
 363         __skb_queue_purge(&tmpq);
 364
 365         return rc;
 366 }
 367
 368 /* tipc_mcast_xmit - deliver message to indicated destination nodes
 369  *                   and to identified node local sockets
 370  * @net: the applicable net namespace
 371  * @pkts: chain of buffers containing message
 372  * @method: send method to be used
 373  * @dests: destination nodes for message.
 374  * @cong_link_cnt: returns number of encountered congested destination links
 375  * Consumes buffer chain.
 376  * Returns 0 if success, otherwise errno
 377  */
 378 int tipc_mcast_xmit(struct net *net, struct sk_buff_head *pkts,
 379                     struct tipc_mc_method *method, struct tipc_nlist *dests,
 380                     u16 *cong_link_cnt)
 381 {
 382         struct sk_buff_head inputq, localq;
 383         bool rcast = method->rcast;
 384         struct tipc_msg *hdr;
 385         struct sk_buff *skb;
 386         int rc = 0;
 387
 388         skb_queue_head_init(&inputq);
 389         __skb_queue_head_init(&localq);
 390
 391         /* Clone packets before they are consumed by next call */
 392         if (dests->local && !tipc_msg_reassemble(pkts, &localq)) {
 393                 rc = -ENOMEM;
 394                 goto exit;
 395         }
 396         /* Send according to determined transmit method */
 397         if (dests->remote) {
 398                 tipc_bcast_select_xmit_method(net, dests->remote, method);
 399
 400                 skb = skb_peek(pkts);
 401                 hdr = buf_msg(skb);
 402                 if (msg_user(hdr) == MSG_FRAGMENTER)
 403                         hdr = msg_inner_hdr(hdr);
 404                 msg_set_is_rcast(hdr, method->rcast);
 405
 406                 /* Switch method ? */
 407                 if (rcast != method->rcast) {
 408                         rc = tipc_mcast_send_sync(net, skb, method, dests);
 409                         if (unlikely(rc)) {
 410                                 pr_err("Unable to send SYN: method %d, rc %d\n",
 411                                        rcast, rc);
 412                                 goto exit;
 413                         }
 414                 }
 415
 416                 if (method->rcast)
 417                         rc = tipc_rcast_xmit(net, pkts, dests, cong_link_cnt);
 418                 else
 419                         rc = tipc_bcast_xmit(net, pkts, cong_link_cnt);
 420         }
 421
 422         if (dests->local) {
 423                 tipc_loopback_trace(net, &localq);
 424                 tipc_sk_mcast_rcv(net, &localq, &inputq);
 425         }
 426 exit:
 427         /* This queue should normally be empty by now */
 428         __skb_queue_purge(pkts);
 429         return rc;
 430 }
 431
 432 /* tipc_bcast_rcv - receive a broadcast packet, and deliver to rcv link
 433  *
 434  * RCU is locked, no other locks set
 435  */
 436 int tipc_bcast_rcv(struct net *net, struct tipc_link *l, struct sk_buff *skb)
 437 {
 438         struct tipc_msg *hdr = buf_msg(skb);
 439         struct sk_buff_head *inputq = &tipc_bc_base(net)->inputq;
 440         struct sk_buff_head xmitq;
 441         int rc;
 442
 443         __skb_queue_head_init(&xmitq);
 444
 445         if (msg_mc_netid(hdr) != tipc_netid(net) || !tipc_link_is_up(l)) {
 446                 kfree_skb(skb);
 447                 return 0;
 448         }
 449
 450         tipc_bcast_lock(net);
 451         if (msg_user(hdr) == BCAST_PROTOCOL)
 452                 rc = tipc_link_bc_nack_rcv(l, skb, &xmitq);
 453         else
 454                 rc = tipc_link_rcv(l, skb, NULL);
 455         tipc_bcast_unlock(net);
 456
 457         tipc_bcbase_xmit(net, &xmitq);
 458
 459         /* Any socket wakeup messages ? */
 460         if (!skb_queue_empty(inputq))
 461                 tipc_sk_rcv(net, inputq);
 462
 463         return rc;
 464 }
 465
 466 /* tipc_bcast_ack_rcv - receive and handle a broadcast acknowledge
 467  *
 468  * RCU is locked, no other locks set
 469  */
 470 void tipc_bcast_ack_rcv(struct net *net, struct tipc_link *l,
 471                         struct tipc_msg *hdr)
 472 {
 473         struct sk_buff_head *inputq = &tipc_bc_base(net)->inputq;
 474         u16 acked = msg_bcast_ack(hdr);
 475         struct sk_buff_head xmitq;
 476
 477         /* Ignore bc acks sent by peer before bcast synch point was received */
 478         if (msg_bc_ack_invalid(hdr))
 479                 return;
 480
 481         __skb_queue_head_init(&xmitq);
 482
 483         tipc_bcast_lock(net);
 484         tipc_link_bc_ack_rcv(l, acked, 0, NULL, &xmitq, NULL);
 485         tipc_bcast_unlock(net);
 486
 487         tipc_bcbase_xmit(net, &xmitq);
 488
 489         /* Any socket wakeup messages ? */
 490         if (!skb_queue_empty(inputq))
 491                 tipc_sk_rcv(net, inputq);
 492 }
 493
 494 /* tipc_bcast_synch_rcv -  check and update rcv link with peer's send state
 495  *
 496  * RCU is locked, no other locks set
 497  */
 498 int tipc_bcast_sync_rcv(struct net *net, struct tipc_link *l,
 499                         struct tipc_msg *hdr,
 500                         struct sk_buff_head *retrq)
 501 {
 502         struct sk_buff_head *inputq = &tipc_bc_base(net)->inputq;
 503         struct tipc_gap_ack_blks *ga;
 504         struct sk_buff_head xmitq;
 505         int rc = 0;
 506
 507         __skb_queue_head_init(&xmitq);
 508
 509         tipc_bcast_lock(net);
 510         if (msg_type(hdr) != STATE_MSG) {
 511                 tipc_link_bc_init_rcv(l, hdr);
 512         } else if (!msg_bc_ack_invalid(hdr)) {
 513                 tipc_get_gap_ack_blks(&ga, l, hdr, false);
 514                 if (!sysctl_tipc_bc_retruni)
 515                         retrq = &xmitq;
 516                 rc = tipc_link_bc_ack_rcv(l, msg_bcast_ack(hdr),
 517                                           msg_bc_gap(hdr), ga, &xmitq,
 518                                           retrq);
 519                 rc |= tipc_link_bc_sync_rcv(l, hdr, &xmitq);
 520         }
 521         tipc_bcast_unlock(net);
 522
 523         tipc_bcbase_xmit(net, &xmitq);
 524
 525         /* Any socket wakeup messages ? */
 526         if (!skb_queue_empty(inputq))
 527                 tipc_sk_rcv(net, inputq);
 528         return rc;
 529 }
 530
 531 /* tipc_bcast_add_peer - add a peer node to broadcast link and bearer
 532  *
 533  * RCU is locked, node lock is set
 534  */
 535 void tipc_bcast_add_peer(struct net *net, struct tipc_link *uc_l,
 536                          struct sk_buff_head *xmitq)
 537 {
 538         struct tipc_link *snd_l = tipc_bc_sndlink(net);
 539
 540         tipc_bcast_lock(net);
 541         tipc_link_add_bc_peer(snd_l, uc_l, xmitq);
 542         tipc_bcbase_select_primary(net);
 543         tipc_bcbase_calc_bc_threshold(net);
 544         tipc_bcast_unlock(net);
 545 }
 546
 547 /* tipc_bcast_remove_peer - remove a peer node from broadcast link and bearer
 548  *
 549  * RCU is locked, node lock is set
 550  */
 551 void tipc_bcast_remove_peer(struct net *net, struct tipc_link *rcv_l)
 552 {
 553         struct tipc_link *snd_l = tipc_bc_sndlink(net);
 554         struct sk_buff_head *inputq = &tipc_bc_base(net)->inputq;
 555         struct sk_buff_head xmitq;
 556
 557         __skb_queue_head_init(&xmitq);
 558
 559         tipc_bcast_lock(net);
 560         tipc_link_remove_bc_peer(snd_l, rcv_l, &xmitq);
 561         tipc_bcbase_select_primary(net);
 562         tipc_bcbase_calc_bc_threshold(net);
 563         tipc_bcast_unlock(net);
 564
 565         tipc_bcbase_xmit(net, &xmitq);
 566
 567         /* Any socket wakeup messages ? */
 568         if (!skb_queue_empty(inputq))
 569                 tipc_sk_rcv(net, inputq);
 570 }
 571
 572 int tipc_bclink_reset_stats(struct net *net, struct tipc_link *l)
 573 {
 574         if (!l)
 575                 return -ENOPROTOOPT;
 576
 577         tipc_bcast_lock(net);
 578         tipc_link_reset_stats(l);
 579         tipc_bcast_unlock(net);
 580         return 0;
 581 }
 582
 583 static int tipc_bc_link_set_queue_limits(struct net *net, u32 max_win)
 584 {
 585         struct tipc_link *l = tipc_bc_sndlink(net);
 586
 587         if (!l)
 588                 return -ENOPROTOOPT;
 589         if (max_win < BCLINK_WIN_MIN)
 590                 max_win = BCLINK_WIN_MIN;
 591         if (max_win > TIPC_MAX_LINK_WIN)
 592                 return -EINVAL;
 593         tipc_bcast_lock(net);
 594         tipc_link_set_queue_limits(l, tipc_link_min_win(l), max_win);
 595         tipc_bcast_unlock(net);
 596         return 0;
 597 }
 598
 599 static int tipc_bc_link_set_broadcast_mode(struct net *net, u32 bc_mode)
 600 {
 601         struct tipc_bc_base *bb = tipc_bc_base(net);
 602
 603         switch (bc_mode) {
 604         case BCLINK_MODE_BCAST:
 605                 if (!bb->bcast_support)
 606                         return -ENOPROTOOPT;
 607
 608                 bb->force_bcast = true;
 609                 bb->force_rcast = false;
 610                 break;
 611         case BCLINK_MODE_RCAST:
 612                 if (!bb->rcast_support)
 613                         return -ENOPROTOOPT;
 614
 615                 bb->force_bcast = false;
 616                 bb->force_rcast = true;
 617                 break;
 618         case BCLINK_MODE_SEL:
 619                 if (!bb->bcast_support || !bb->rcast_support)
 620                         return -ENOPROTOOPT;
 621
 622                 bb->force_bcast = false;
 623                 bb->force_rcast = false;
 624                 break;
 625         default:
 626                 return -EINVAL;
 627         }
 628
 629         return 0;
 630 }
 631
 632 static int tipc_bc_link_set_broadcast_ratio(struct net *net, u32 bc_ratio)
 633 {
 634         struct tipc_bc_base *bb = tipc_bc_base(net);
 635
 636         if (!bb->bcast_support || !bb->rcast_support)
 637                 return -ENOPROTOOPT;
 638
 639         if (bc_ratio > 100 || bc_ratio <= 0)
 640                 return -EINVAL;
 641
 642         bb->rc_ratio = bc_ratio;
 643         tipc_bcast_lock(net);
 644         tipc_bcbase_calc_bc_threshold(net);
 645         tipc_bcast_unlock(net);
 646
 647         return 0;
 648 }
 649
 650 int tipc_nl_bc_link_set(struct net *net, struct nlattr *attrs[])
 651 {
 652         int err;
 653         u32 win;
 654         u32 bc_mode;
 655         u32 bc_ratio;
 656         struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
 657
 658         if (!attrs[TIPC_NLA_LINK_PROP])
 659                 return -EINVAL;
 660
 661         err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP], props);
 662         if (err)
 663                 return err;
 664
 665         if (!props[TIPC_NLA_PROP_WIN] &&
 666             !props[TIPC_NLA_PROP_BROADCAST] &&
 667             !props[TIPC_NLA_PROP_BROADCAST_RATIO]) {
 668                 return -EOPNOTSUPP;
 669         }
 670
 671         if (props[TIPC_NLA_PROP_BROADCAST]) {
 672                 bc_mode = nla_get_u32(props[TIPC_NLA_PROP_BROADCAST]);
 673                 err = tipc_bc_link_set_broadcast_mode(net, bc_mode);
 674         }
 675
 676         if (!err && props[TIPC_NLA_PROP_BROADCAST_RATIO]) {
 677                 bc_ratio = nla_get_u32(props[TIPC_NLA_PROP_BROADCAST_RATIO]);
 678                 err = tipc_bc_link_set_broadcast_ratio(net, bc_ratio);
 679         }
 680
 681         if (!err && props[TIPC_NLA_PROP_WIN]) {
 682                 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
 683                 err = tipc_bc_link_set_queue_limits(net, win);
 684         }
 685
 686         return err;
 687 }
 688
 689 int tipc_bcast_init(struct net *net)
 690 {
 691         struct tipc_net *tn = tipc_net(net);
 692         struct tipc_bc_base *bb = NULL;
 693         struct tipc_link *l = NULL;
 694
 695         bb = kzalloc(sizeof(*bb), GFP_KERNEL);
 696         if (!bb)
 697                 goto enomem;
 698         tn->bcbase = bb;
 699         spin_lock_init(&tipc_net(net)->bclock);
 700
 701         if (!tipc_link_bc_create(net, 0, 0, NULL,
 702                                  FB_MTU,
 703                                  BCLINK_WIN_DEFAULT,
 704                                  BCLINK_WIN_DEFAULT,
 705                                  0,
 706                                  &bb->inputq,
 707                                  NULL,
 708                                  NULL,
 709                                  &l))
 710                 goto enomem;
 711         bb->link = l;
 712         tn->bcl = l;
 713         bb->rc_ratio = 10;
 714         bb->rcast_support = true;
 715         return 0;
 716 enomem:
 717         kfree(bb);
 718         kfree(l);
 719         return -ENOMEM;
 720 }
 721
 722 void tipc_bcast_stop(struct net *net)
 723 {
 724         struct tipc_net *tn = net_generic(net, tipc_net_id);
 725
 726         synchronize_net();
 727         kfree(tn->bcbase);
 728         kfree(tn->bcl);
 729 }
 730
 731 void tipc_nlist_init(struct tipc_nlist *nl, u32 self)
 732 {
 733         memset(nl, 0, sizeof(*nl));
 734         INIT_LIST_HEAD(&nl->list);
 735         nl->self = self;
 736 }
 737
 738 void tipc_nlist_add(struct tipc_nlist *nl, u32 node)
 739 {
 740         if (node == nl->self)
 741                 nl->local = true;
 742         else if (tipc_dest_push(&nl->list, node, 0))
 743                 nl->remote++;
 744 }
 745
 746 void tipc_nlist_del(struct tipc_nlist *nl, u32 node)
 747 {
 748         if (node == nl->self)
 749                 nl->local = false;
 750         else if (tipc_dest_del(&nl->list, node, 0))
 751                 nl->remote--;
 752 }
 753
 754 void tipc_nlist_purge(struct tipc_nlist *nl)
 755 {
 756         tipc_dest_list_purge(&nl->list);
 757         nl->remote = 0;
 758         nl->local = false;
 759 }
 760
 761 u32 tipc_bcast_get_mode(struct net *net)
 762 {
 763         struct tipc_bc_base *bb = tipc_bc_base(net);
 764
 765         if (bb->force_bcast)
 766                 return BCLINK_MODE_BCAST;
 767
 768         if (bb->force_rcast)
 769                 return BCLINK_MODE_RCAST;
 770
 771         if (bb->bcast_support && bb->rcast_support)
 772                 return BCLINK_MODE_SEL;
 773
 774         return 0;
 775 }
 776
 777 u32 tipc_bcast_get_broadcast_ratio(struct net *net)
 778 {
 779         struct tipc_bc_base *bb = tipc_bc_base(net);
 780
 781         return bb->rc_ratio;
 782 }
 783
 784 void tipc_mcast_filter_msg(struct net *net, struct sk_buff_head *defq,
 785                            struct sk_buff_head *inputq)
 786 {
 787         struct sk_buff *skb, *_skb, *tmp;
 788         struct tipc_msg *hdr, *_hdr;
 789         bool match = false;
 790         u32 node, port;
 791
 792         skb = skb_peek(inputq);
 793         if (!skb)
 794                 return;
 795
 796         hdr = buf_msg(skb);
 797
 798         if (likely(!msg_is_syn(hdr) && skb_queue_empty(defq)))
 799                 return;
 800
 801         node = msg_orignode(hdr);
 802         if (node == tipc_own_addr(net))
 803                 return;
 804
 805         port = msg_origport(hdr);
 806
 807         /* Has the twin SYN message already arrived ? */
 808         skb_queue_walk(defq, _skb) {
 809                 _hdr = buf_msg(_skb);
 810                 if (msg_orignode(_hdr) != node)
 811                         continue;
 812                 if (msg_origport(_hdr) != port)
 813                         continue;
 814                 match = true;
 815                 break;
 816         }
 817
 818         if (!match) {
 819                 if (!msg_is_syn(hdr))
 820                         return;
 821                 __skb_dequeue(inputq);
 822                 __skb_queue_tail(defq, skb);
 823                 return;
 824         }
 825
 826         /* Deliver non-SYN message from other link, otherwise queue it */
 827         if (!msg_is_syn(hdr)) {
 828                 if (msg_is_rcast(hdr) != msg_is_rcast(_hdr))
 829                         return;
 830                 __skb_dequeue(inputq);
 831                 __skb_queue_tail(defq, skb);
 832                 return;
 833         }
 834
 835         /* Queue non-SYN/SYN message from same link */
 836         if (msg_is_rcast(hdr) == msg_is_rcast(_hdr)) {
 837                 __skb_dequeue(inputq);
 838                 __skb_queue_tail(defq, skb);
 839                 return;
 840         }
 841
 842         /* Matching SYN messages => return the one with data, if any */
 843         __skb_unlink(_skb, defq);
 844         if (msg_data_sz(hdr)) {
 845                 kfree_skb(_skb);
 846         } else {
 847                 __skb_dequeue(inputq);
 848                 kfree_skb(skb);
 849                 __skb_queue_tail(inputq, _skb);
 850         }
 851
 852         /* Deliver subsequent non-SYN messages from same peer */
 853         skb_queue_walk_safe(defq, _skb, tmp) {
 854                 _hdr = buf_msg(_skb);
 855                 if (msg_orignode(_hdr) != node)
 856                         continue;
 857                 if (msg_origport(_hdr) != port)
 858                         continue;
 859                 if (msg_is_syn(_hdr))
 860                         break;
 861                 __skb_unlink(_skb, defq);
 862                 __skb_queue_tail(inputq, _skb);
 863         }
 864 }