net/tipc/bcast.c

   1 /*
   2  * net/tipc/bcast.c: TIPC broadcast code
   3  *
   4  * Copyright (c) 2004-2006, 2014-2015, 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 "name_distr.h"
  43 #include "link.h"
  44 #include "node.h"
  45
  46 #define BCLINK_WIN_DEFAULT      50      /* bcast link window size (default) */
  47 #define BCLINK_WIN_MIN          32      /* bcast minimum link window size */
  48
  49 const char tipc_bclink_name[] = "broadcast-link";
  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  * @dest: array keeping number of reachable destinations per bearer
  56  * @primary_bearer: a bearer having links to all broadcast destinations, if any
  57  */
  58 struct tipc_bc_base {
  59         struct tipc_link *link;
  60         struct sk_buff_head inputq;
  61         int dests[MAX_BEARERS];
  62         int primary_bearer;
  63 };
  64
  65 static struct tipc_bc_base *tipc_bc_base(struct net *net)
  66 {
  67         return tipc_net(net)->bcbase;
  68 }
  69
  70 int tipc_bcast_get_mtu(struct net *net)
  71 {
  72         return tipc_link_mtu(tipc_bc_sndlink(net));
  73 }
  74
  75 /* tipc_bcbase_select_primary(): find a bearer with links to all destinations,
  76  *                               if any, and make it primary bearer
  77  */
  78 static void tipc_bcbase_select_primary(struct net *net)
  79 {
  80         struct tipc_bc_base *bb = tipc_bc_base(net);
  81         int all_dests =  tipc_link_bc_peers(bb->link);
  82         int i, mtu;
  83
  84         bb->primary_bearer = INVALID_BEARER_ID;
  85
  86         if (!all_dests)
  87                 return;
  88
  89         for (i = 0; i < MAX_BEARERS; i++) {
  90                 if (!bb->dests[i])
  91                         continue;
  92
  93                 mtu = tipc_bearer_mtu(net, i);
  94                 if (mtu < tipc_link_mtu(bb->link))
  95                         tipc_link_set_mtu(bb->link, mtu);
  96
  97                 if (bb->dests[i] < all_dests)
  98                         continue;
  99
 100                 bb->primary_bearer = i;
 101
 102                 /* Reduce risk that all nodes select same primary */
 103                 if ((i ^ tipc_own_addr(net)) & 1)
 104                         break;
 105         }
 106 }
 107
 108 void tipc_bcast_inc_bearer_dst_cnt(struct net *net, int bearer_id)
 109 {
 110         struct tipc_bc_base *bb = tipc_bc_base(net);
 111
 112         tipc_bcast_lock(net);
 113         bb->dests[bearer_id]++;
 114         tipc_bcbase_select_primary(net);
 115         tipc_bcast_unlock(net);
 116 }
 117
 118 void tipc_bcast_dec_bearer_dst_cnt(struct net *net, int bearer_id)
 119 {
 120         struct tipc_bc_base *bb = tipc_bc_base(net);
 121
 122         tipc_bcast_lock(net);
 123         bb->dests[bearer_id]--;
 124         tipc_bcbase_select_primary(net);
 125         tipc_bcast_unlock(net);
 126 }
 127
 128 /* tipc_bcbase_xmit - broadcast a packet queue across one or more bearers
 129  *
 130  * Note that number of reachable destinations, as indicated in the dests[]
 131  * array, may transitionally differ from the number of destinations indicated
 132  * in each sent buffer. We can sustain this. Excess destination nodes will
 133  * drop and never acknowledge the unexpected packets, and missing destinations
 134  * will either require retransmission (if they are just about to be added to
 135  * the bearer), or be removed from the buffer's 'ackers' counter (if they
 136  * just went down)
 137  */
 138 static void tipc_bcbase_xmit(struct net *net, struct sk_buff_head *xmitq)
 139 {
 140         int bearer_id;
 141         struct tipc_bc_base *bb = tipc_bc_base(net);
 142         struct sk_buff *skb, *_skb;
 143         struct sk_buff_head _xmitq;
 144
 145         if (skb_queue_empty(xmitq))
 146                 return;
 147
 148         /* The typical case: at least one bearer has links to all nodes */
 149         bearer_id = bb->primary_bearer;
 150         if (bearer_id >= 0) {
 151                 tipc_bearer_bc_xmit(net, bearer_id, xmitq);
 152                 return;
 153         }
 154
 155         /* We have to transmit across all bearers */
 156         skb_queue_head_init(&_xmitq);
 157         for (bearer_id = 0; bearer_id < MAX_BEARERS; bearer_id++) {
 158                 if (!bb->dests[bearer_id])
 159                         continue;
 160
 161                 skb_queue_walk(xmitq, skb) {
 162                         _skb = pskb_copy_for_clone(skb, GFP_ATOMIC);
 163                         if (!_skb)
 164                                 break;
 165                         __skb_queue_tail(&_xmitq, _skb);
 166                 }
 167                 tipc_bearer_bc_xmit(net, bearer_id, &_xmitq);
 168         }
 169         __skb_queue_purge(xmitq);
 170         __skb_queue_purge(&_xmitq);
 171 }
 172
 173 /* tipc_bcast_xmit - deliver buffer chain to all nodes in cluster
 174  *                    and to identified node local sockets
 175  * @net: the applicable net namespace
 176  * @list: chain of buffers containing message
 177  * Consumes the buffer chain, except when returning -ELINKCONG
 178  * Returns 0 if success, otherwise errno: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE
 179  */
 180 int tipc_bcast_xmit(struct net *net, struct sk_buff_head *list)
 181 {
 182         struct tipc_link *l = tipc_bc_sndlink(net);
 183         struct sk_buff_head xmitq, inputq, rcvq;
 184         int rc = 0;
 185
 186         __skb_queue_head_init(&rcvq);
 187         __skb_queue_head_init(&xmitq);
 188         skb_queue_head_init(&inputq);
 189
 190         /* Prepare message clone for local node */
 191         if (unlikely(!tipc_msg_reassemble(list, &rcvq)))
 192                 return -EHOSTUNREACH;
 193
 194         tipc_bcast_lock(net);
 195         if (tipc_link_bc_peers(l))
 196                 rc = tipc_link_xmit(l, list, &xmitq);
 197         tipc_bcast_unlock(net);
 198
 199         /* Don't send to local node if adding to link failed */
 200         if (unlikely(rc)) {
 201                 __skb_queue_purge(&rcvq);
 202                 return rc;
 203         }
 204
 205         /* Broadcast to all nodes, inluding local node */
 206         tipc_bcbase_xmit(net, &xmitq);
 207         tipc_sk_mcast_rcv(net, &rcvq, &inputq);
 208         __skb_queue_purge(list);
 209         return 0;
 210 }
 211
 212 /* tipc_bcast_rcv - receive a broadcast packet, and deliver to rcv link
 213  *
 214  * RCU is locked, no other locks set
 215  */
 216 int tipc_bcast_rcv(struct net *net, struct tipc_link *l, struct sk_buff *skb)
 217 {
 218         struct tipc_msg *hdr = buf_msg(skb);
 219         struct sk_buff_head *inputq = &tipc_bc_base(net)->inputq;
 220         struct sk_buff_head xmitq;
 221         int rc;
 222
 223         __skb_queue_head_init(&xmitq);
 224
 225         if (msg_mc_netid(hdr) != tipc_netid(net) || !tipc_link_is_up(l)) {
 226                 kfree_skb(skb);
 227                 return 0;
 228         }
 229
 230         tipc_bcast_lock(net);
 231         if (msg_user(hdr) == BCAST_PROTOCOL)
 232                 rc = tipc_link_bc_nack_rcv(l, skb, &xmitq);
 233         else
 234                 rc = tipc_link_rcv(l, skb, NULL);
 235         tipc_bcast_unlock(net);
 236
 237         tipc_bcbase_xmit(net, &xmitq);
 238
 239         /* Any socket wakeup messages ? */
 240         if (!skb_queue_empty(inputq))
 241                 tipc_sk_rcv(net, inputq);
 242
 243         return rc;
 244 }
 245
 246 /* tipc_bcast_ack_rcv - receive and handle a broadcast acknowledge
 247  *
 248  * RCU is locked, no other locks set
 249  */
 250 void tipc_bcast_ack_rcv(struct net *net, struct tipc_link *l, u32 acked)
 251 {
 252         struct sk_buff_head *inputq = &tipc_bc_base(net)->inputq;
 253         struct sk_buff_head xmitq;
 254
 255         __skb_queue_head_init(&xmitq);
 256
 257         tipc_bcast_lock(net);
 258         tipc_link_bc_ack_rcv(l, acked, &xmitq);
 259         tipc_bcast_unlock(net);
 260
 261         tipc_bcbase_xmit(net, &xmitq);
 262
 263         /* Any socket wakeup messages ? */
 264         if (!skb_queue_empty(inputq))
 265                 tipc_sk_rcv(net, inputq);
 266 }
 267
 268 /* tipc_bcast_synch_rcv -  check and update rcv link with peer's send state
 269  *
 270  * RCU is locked, no other locks set
 271  */
 272 void tipc_bcast_sync_rcv(struct net *net, struct tipc_link *l,
 273                          struct tipc_msg *hdr)
 274 {
 275         struct sk_buff_head *inputq = &tipc_bc_base(net)->inputq;
 276         struct sk_buff_head xmitq;
 277
 278         __skb_queue_head_init(&xmitq);
 279
 280         tipc_bcast_lock(net);
 281         if (msg_type(hdr) == STATE_MSG) {
 282                 tipc_link_bc_ack_rcv(l, msg_bcast_ack(hdr), &xmitq);
 283                 tipc_link_bc_sync_rcv(l, hdr, &xmitq);
 284         } else {
 285                 tipc_link_bc_init_rcv(l, hdr);
 286         }
 287         tipc_bcast_unlock(net);
 288
 289         tipc_bcbase_xmit(net, &xmitq);
 290
 291         /* Any socket wakeup messages ? */
 292         if (!skb_queue_empty(inputq))
 293                 tipc_sk_rcv(net, inputq);
 294 }
 295
 296 /* tipc_bcast_add_peer - add a peer node to broadcast link and bearer
 297  *
 298  * RCU is locked, node lock is set
 299  */
 300 void tipc_bcast_add_peer(struct net *net, struct tipc_link *uc_l,
 301                          struct sk_buff_head *xmitq)
 302 {
 303         struct tipc_link *snd_l = tipc_bc_sndlink(net);
 304
 305         tipc_bcast_lock(net);
 306         tipc_link_add_bc_peer(snd_l, uc_l, xmitq);
 307         tipc_bcbase_select_primary(net);
 308         tipc_bcast_unlock(net);
 309 }
 310
 311 /* tipc_bcast_remove_peer - remove a peer node from broadcast link and bearer
 312  *
 313  * RCU is locked, node lock is set
 314  */
 315 void tipc_bcast_remove_peer(struct net *net, struct tipc_link *rcv_l)
 316 {
 317         struct tipc_link *snd_l = tipc_bc_sndlink(net);
 318         struct sk_buff_head *inputq = &tipc_bc_base(net)->inputq;
 319         struct sk_buff_head xmitq;
 320
 321         __skb_queue_head_init(&xmitq);
 322
 323         tipc_bcast_lock(net);
 324         tipc_link_remove_bc_peer(snd_l, rcv_l, &xmitq);
 325         tipc_bcbase_select_primary(net);
 326         tipc_bcast_unlock(net);
 327
 328         tipc_bcbase_xmit(net, &xmitq);
 329
 330         /* Any socket wakeup messages ? */
 331         if (!skb_queue_empty(inputq))
 332                 tipc_sk_rcv(net, inputq);
 333 }
 334
 335 static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb,
 336                                       struct tipc_stats *stats)
 337 {
 338         int i;
 339         struct nlattr *nest;
 340
 341         struct nla_map {
 342                 __u32 key;
 343                 __u32 val;
 344         };
 345
 346         struct nla_map map[] = {
 347                 {TIPC_NLA_STATS_RX_INFO, stats->recv_info},
 348                 {TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments},
 349                 {TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented},
 350                 {TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles},
 351                 {TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled},
 352                 {TIPC_NLA_STATS_TX_INFO, stats->sent_info},
 353                 {TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments},
 354                 {TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented},
 355                 {TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles},
 356                 {TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled},
 357                 {TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks},
 358                 {TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv},
 359                 {TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks},
 360                 {TIPC_NLA_STATS_TX_ACKS, stats->sent_acks},
 361                 {TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted},
 362                 {TIPC_NLA_STATS_DUPLICATES, stats->duplicates},
 363                 {TIPC_NLA_STATS_LINK_CONGS, stats->link_congs},
 364                 {TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz},
 365                 {TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ?
 366                         (stats->accu_queue_sz / stats->queue_sz_counts) : 0}
 367         };
 368
 369         nest = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
 370         if (!nest)
 371                 return -EMSGSIZE;
 372
 373         for (i = 0; i <  ARRAY_SIZE(map); i++)
 374                 if (nla_put_u32(skb, map[i].key, map[i].val))
 375                         goto msg_full;
 376
 377         nla_nest_end(skb, nest);
 378
 379         return 0;
 380 msg_full:
 381         nla_nest_cancel(skb, nest);
 382
 383         return -EMSGSIZE;
 384 }
 385
 386 int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg)
 387 {
 388         int err;
 389         void *hdr;
 390         struct nlattr *attrs;
 391         struct nlattr *prop;
 392         struct tipc_net *tn = net_generic(net, tipc_net_id);
 393         struct tipc_link *bcl = tn->bcl;
 394
 395         if (!bcl)
 396                 return 0;
 397
 398         tipc_bcast_lock(net);
 399
 400         hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
 401                           NLM_F_MULTI, TIPC_NL_LINK_GET);
 402         if (!hdr)
 403                 return -EMSGSIZE;
 404
 405         attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
 406         if (!attrs)
 407                 goto msg_full;
 408
 409         /* The broadcast link is always up */
 410         if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
 411                 goto attr_msg_full;
 412
 413         if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST))
 414                 goto attr_msg_full;
 415         if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name))
 416                 goto attr_msg_full;
 417         if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, bcl->rcv_nxt))
 418                 goto attr_msg_full;
 419         if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, bcl->snd_nxt))
 420                 goto attr_msg_full;
 421
 422         prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
 423         if (!prop)
 424                 goto attr_msg_full;
 425         if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->window))
 426                 goto prop_msg_full;
 427         nla_nest_end(msg->skb, prop);
 428
 429         err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats);
 430         if (err)
 431                 goto attr_msg_full;
 432
 433         tipc_bcast_unlock(net);
 434         nla_nest_end(msg->skb, attrs);
 435         genlmsg_end(msg->skb, hdr);
 436
 437         return 0;
 438
 439 prop_msg_full:
 440         nla_nest_cancel(msg->skb, prop);
 441 attr_msg_full:
 442         nla_nest_cancel(msg->skb, attrs);
 443 msg_full:
 444         tipc_bcast_unlock(net);
 445         genlmsg_cancel(msg->skb, hdr);
 446
 447         return -EMSGSIZE;
 448 }
 449
 450 int tipc_bclink_reset_stats(struct net *net)
 451 {
 452         struct tipc_net *tn = net_generic(net, tipc_net_id);
 453         struct tipc_link *bcl = tn->bcl;
 454
 455         if (!bcl)
 456                 return -ENOPROTOOPT;
 457
 458         tipc_bcast_lock(net);
 459         memset(&bcl->stats, 0, sizeof(bcl->stats));
 460         tipc_bcast_unlock(net);
 461         return 0;
 462 }
 463
 464 static int tipc_bc_link_set_queue_limits(struct net *net, u32 limit)
 465 {
 466         struct tipc_link *l = tipc_bc_sndlink(net);
 467
 468         if (!l)
 469                 return -ENOPROTOOPT;
 470         if (limit < BCLINK_WIN_MIN)
 471                 limit = BCLINK_WIN_MIN;
 472         if (limit > TIPC_MAX_LINK_WIN)
 473                 return -EINVAL;
 474         tipc_bcast_lock(net);
 475         tipc_link_set_queue_limits(l, limit);
 476         tipc_bcast_unlock(net);
 477         return 0;
 478 }
 479
 480 int tipc_nl_bc_link_set(struct net *net, struct nlattr *attrs[])
 481 {
 482         int err;
 483         u32 win;
 484         struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
 485
 486         if (!attrs[TIPC_NLA_LINK_PROP])
 487                 return -EINVAL;
 488
 489         err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP], props);
 490         if (err)
 491                 return err;
 492
 493         if (!props[TIPC_NLA_PROP_WIN])
 494                 return -EOPNOTSUPP;
 495
 496         win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
 497
 498         return tipc_bc_link_set_queue_limits(net, win);
 499 }
 500
 501 int tipc_bcast_init(struct net *net)
 502 {
 503         struct tipc_net *tn = tipc_net(net);
 504         struct tipc_bc_base *bb = NULL;
 505         struct tipc_link *l = NULL;
 506
 507         bb = kzalloc(sizeof(*bb), GFP_ATOMIC);
 508         if (!bb)
 509                 goto enomem;
 510         tn->bcbase = bb;
 511         spin_lock_init(&tipc_net(net)->bclock);
 512
 513         if (!tipc_link_bc_create(net, 0, 0,
 514                                  U16_MAX,
 515                                  BCLINK_WIN_DEFAULT,
 516                                  0,
 517                                  &bb->inputq,
 518                                  NULL,
 519                                  NULL,
 520                                  &l))
 521                 goto enomem;
 522         bb->link = l;
 523         tn->bcl = l;
 524         return 0;
 525 enomem:
 526         kfree(bb);
 527         kfree(l);
 528         return -ENOMEM;
 529 }
 530
 531 void tipc_bcast_reinit(struct net *net)
 532 {
 533         struct tipc_bc_base *b = tipc_bc_base(net);
 534
 535         msg_set_prevnode(b->link->pmsg, tipc_own_addr(net));
 536 }
 537
 538 void tipc_bcast_stop(struct net *net)
 539 {
 540         struct tipc_net *tn = net_generic(net, tipc_net_id);
 541
 542         synchronize_net();
 543         kfree(tn->bcbase);
 544         kfree(tn->bcl);
 545 }