net/tipc/name_table.c

   1 /*
   2  * net/tipc/name_table.c: TIPC name table code
   3  *
   4  * Copyright (c) 2000-2006, Ericsson AB
   5  * Copyright (c) 2004-2008, Wind River Systems
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. Neither the names of the copyright holders nor the names of its
  17  *    contributors may be used to endorse or promote products derived from
  18  *    this software without specific prior written permission.
  19  *
  20  * Alternatively, this software may be distributed under the terms of the
  21  * GNU General Public License ("GPL") version 2 as published by the Free
  22  * Software Foundation.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  25  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  28  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  29  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  30  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  31  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  32  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  33  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  34  * POSSIBILITY OF SUCH DAMAGE.
  35  */
  36
  37 #include "core.h"
  38 #include "config.h"
  39 #include "dbg.h"
  40 #include "name_table.h"
  41 #include "name_distr.h"
  42 #include "addr.h"
  43 #include "node_subscr.h"
  44 #include "subscr.h"
  45 #include "port.h"
  46 #include "cluster.h"
  47 #include "bcast.h"
  48
  49 static int tipc_nametbl_size = 1024;            /* must be a power of 2 */
  50
  51 /**
  52  * struct sub_seq - container for all published instances of a name sequence
  53  * @lower: name sequence lower bound
  54  * @upper: name sequence upper bound
  55  * @node_list: circular list of publications made by own node
  56  * @cluster_list: circular list of publications made by own cluster
  57  * @zone_list: circular list of publications made by own zone
  58  * @node_list_size: number of entries in "node_list"
  59  * @cluster_list_size: number of entries in "cluster_list"
  60  * @zone_list_size: number of entries in "zone_list"
  61  *
  62  * Note: The zone list always contains at least one entry, since all
  63  *       publications of the associated name sequence belong to it.
  64  *       (The cluster and node lists may be empty.)
  65  */
  66
  67 struct sub_seq {
  68         u32 lower;
  69         u32 upper;
  70         struct publication *node_list;
  71         struct publication *cluster_list;
  72         struct publication *zone_list;
  73         u32 node_list_size;
  74         u32 cluster_list_size;
  75         u32 zone_list_size;
  76 };
  77
  78 /**
  79  * struct name_seq - container for all published instances of a name type
  80  * @type: 32 bit 'type' value for name sequence
  81  * @sseq: pointer to dynamically-sized array of sub-sequences of this 'type';
  82  *        sub-sequences are sorted in ascending order
  83  * @alloc: number of sub-sequences currently in array
  84  * @first_free: array index of first unused sub-sequence entry
  85  * @ns_list: links to adjacent name sequences in hash chain
  86  * @subscriptions: list of subscriptions for this 'type'
  87  * @lock: spinlock controlling access to publication lists of all sub-sequences
  88  */
  89
  90 struct name_seq {
  91         u32 type;
  92         struct sub_seq *sseqs;
  93         u32 alloc;
  94         u32 first_free;
  95         struct hlist_node ns_list;
  96         struct list_head subscriptions;
  97         spinlock_t lock;
  98 };
  99
 100 /**
 101  * struct name_table - table containing all existing port name publications
 102  * @types: pointer to fixed-sized array of name sequence lists,
 103  *         accessed via hashing on 'type'; name sequence lists are *not* sorted
 104  * @local_publ_count: number of publications issued by this node
 105  */
 106
 107 struct name_table {
 108         struct hlist_head *types;
 109         u32 local_publ_count;
 110 };
 111
 112 static struct name_table table = { NULL } ;
 113 static atomic_t rsv_publ_ok = ATOMIC_INIT(0);
 114 DEFINE_RWLOCK(tipc_nametbl_lock);
 115
 116
 117 static int hash(int x)
 118 {
 119         return(x & (tipc_nametbl_size - 1));
 120 }
 121
 122 /**
 123  * publ_create - create a publication structure
 124  */
 125
 126 static struct publication *publ_create(u32 type, u32 lower, u32 upper,
 127                                        u32 scope, u32 node, u32 port_ref,
 128                                        u32 key)
 129 {
 130         struct publication *publ = kzalloc(sizeof(*publ), GFP_ATOMIC);
 131         if (publ == NULL) {
 132                 warn("Publication creation failure, no memory\n");
 133                 return NULL;
 134         }
 135
 136         publ->type = type;
 137         publ->lower = lower;
 138         publ->upper = upper;
 139         publ->scope = scope;
 140         publ->node = node;
 141         publ->ref = port_ref;
 142         publ->key = key;
 143         INIT_LIST_HEAD(&publ->local_list);
 144         INIT_LIST_HEAD(&publ->pport_list);
 145         INIT_LIST_HEAD(&publ->subscr.nodesub_list);
 146         return publ;
 147 }
 148
 149 /**
 150  * tipc_subseq_alloc - allocate a specified number of sub-sequence structures
 151  */
 152
 153 static struct sub_seq *tipc_subseq_alloc(u32 cnt)
 154 {
 155         struct sub_seq *sseq = kcalloc(cnt, sizeof(struct sub_seq), GFP_ATOMIC);
 156         return sseq;
 157 }
 158
 159 /**
 160  * tipc_nameseq_create - create a name sequence structure for the specified 'type'
 161  *
 162  * Allocates a single sub-sequence structure and sets it to all 0's.
 163  */
 164
 165 static struct name_seq *tipc_nameseq_create(u32 type, struct hlist_head *seq_head)
 166 {
 167         struct name_seq *nseq = kzalloc(sizeof(*nseq), GFP_ATOMIC);
 168         struct sub_seq *sseq = tipc_subseq_alloc(1);
 169
 170         if (!nseq || !sseq) {
 171                 warn("Name sequence creation failed, no memory\n");
 172                 kfree(nseq);
 173                 kfree(sseq);
 174                 return NULL;
 175         }
 176
 177         spin_lock_init(&nseq->lock);
 178         nseq->type = type;
 179         nseq->sseqs = sseq;
 180         dbg("tipc_nameseq_create(): nseq = %p, type %u, ssseqs %p, ff: %u\n",
 181             nseq, type, nseq->sseqs, nseq->first_free);
 182         nseq->alloc = 1;
 183         INIT_HLIST_NODE(&nseq->ns_list);
 184         INIT_LIST_HEAD(&nseq->subscriptions);
 185         hlist_add_head(&nseq->ns_list, seq_head);
 186         return nseq;
 187 }
 188
 189 /**
 190  * nameseq_find_subseq - find sub-sequence (if any) matching a name instance
 191  *
 192  * Very time-critical, so binary searches through sub-sequence array.
 193  */
 194
 195 static struct sub_seq *nameseq_find_subseq(struct name_seq *nseq,
 196                                            u32 instance)
 197 {
 198         struct sub_seq *sseqs = nseq->sseqs;
 199         int low = 0;
 200         int high = nseq->first_free - 1;
 201         int mid;
 202
 203         while (low <= high) {
 204                 mid = (low + high) / 2;
 205                 if (instance < sseqs[mid].lower)
 206                         high = mid - 1;
 207                 else if (instance > sseqs[mid].upper)
 208                         low = mid + 1;
 209                 else
 210                         return &sseqs[mid];
 211         }
 212         return NULL;
 213 }
 214
 215 /**
 216  * nameseq_locate_subseq - determine position of name instance in sub-sequence
 217  *
 218  * Returns index in sub-sequence array of the entry that contains the specified
 219  * instance value; if no entry contains that value, returns the position
 220  * where a new entry for it would be inserted in the array.
 221  *
 222  * Note: Similar to binary search code for locating a sub-sequence.
 223  */
 224
 225 static u32 nameseq_locate_subseq(struct name_seq *nseq, u32 instance)
 226 {
 227         struct sub_seq *sseqs = nseq->sseqs;
 228         int low = 0;
 229         int high = nseq->first_free - 1;
 230         int mid;
 231
 232         while (low <= high) {
 233                 mid = (low + high) / 2;
 234                 if (instance < sseqs[mid].lower)
 235                         high = mid - 1;
 236                 else if (instance > sseqs[mid].upper)
 237                         low = mid + 1;
 238                 else
 239                         return mid;
 240         }
 241         return low;
 242 }
 243
 244 /**
 245  * tipc_nameseq_insert_publ -
 246  */
 247
 248 static struct publication *tipc_nameseq_insert_publ(struct name_seq *nseq,
 249                                                     u32 type, u32 lower, u32 upper,
 250                                                     u32 scope, u32 node, u32 port, u32 key)
 251 {
 252         struct subscription *s;
 253         struct subscription *st;
 254         struct publication *publ;
 255         struct sub_seq *sseq;
 256         int created_subseq = 0;
 257
 258         sseq = nameseq_find_subseq(nseq, lower);
 259         dbg("nameseq_ins: for seq %p, {%u,%u}, found sseq %p\n",
 260             nseq, type, lower, sseq);
 261         if (sseq) {
 262
 263                 /* Lower end overlaps existing entry => need an exact match */
 264
 265                 if ((sseq->lower != lower) || (sseq->upper != upper)) {
 266                         warn("Cannot publish {%u,%u,%u}, overlap error\n",
 267                              type, lower, upper);
 268                         return NULL;
 269                 }
 270         } else {
 271                 u32 inspos;
 272                 struct sub_seq *freesseq;
 273
 274                 /* Find where lower end should be inserted */
 275
 276                 inspos = nameseq_locate_subseq(nseq, lower);
 277
 278                 /* Fail if upper end overlaps into an existing entry */
 279
 280                 if ((inspos < nseq->first_free) &&
 281                     (upper >= nseq->sseqs[inspos].lower)) {
 282                         warn("Cannot publish {%u,%u,%u}, overlap error\n",
 283                              type, lower, upper);
 284                         return NULL;
 285                 }
 286
 287                 /* Ensure there is space for new sub-sequence */
 288
 289                 if (nseq->first_free == nseq->alloc) {
 290                         struct sub_seq *sseqs = tipc_subseq_alloc(nseq->alloc * 2);
 291
 292                         if (!sseqs) {
 293                                 warn("Cannot publish {%u,%u,%u}, no memory\n",
 294                                      type, lower, upper);
 295                                 return NULL;
 296                         }
 297                         dbg("Allocated %u more sseqs\n", nseq->alloc);
 298                         memcpy(sseqs, nseq->sseqs,
 299                                nseq->alloc * sizeof(struct sub_seq));
 300                         kfree(nseq->sseqs);
 301                         nseq->sseqs = sseqs;
 302                         nseq->alloc *= 2;
 303                 }
 304                 dbg("Have %u sseqs for type %u\n", nseq->alloc, type);
 305
 306                 /* Insert new sub-sequence */
 307
 308                 dbg("ins in pos %u, ff = %u\n", inspos, nseq->first_free);
 309                 sseq = &nseq->sseqs[inspos];
 310                 freesseq = &nseq->sseqs[nseq->first_free];
 311                 memmove(sseq + 1, sseq, (freesseq - sseq) * sizeof (*sseq));
 312                 memset(sseq, 0, sizeof (*sseq));
 313                 nseq->first_free++;
 314                 sseq->lower = lower;
 315                 sseq->upper = upper;
 316                 created_subseq = 1;
 317         }
 318         dbg("inserting {%u,%u,%u} from <0x%x:%u> into sseq %p(%u,%u) of seq %p\n",
 319             type, lower, upper, node, port, sseq,
 320             sseq->lower, sseq->upper, nseq);
 321
 322         /* Insert a publication: */
 323
 324         publ = publ_create(type, lower, upper, scope, node, port, key);
 325         if (!publ)
 326                 return NULL;
 327         dbg("inserting publ %p, node=0x%x publ->node=0x%x, subscr->node=%p\n",
 328             publ, node, publ->node, publ->subscr.node);
 329
 330         sseq->zone_list_size++;
 331         if (!sseq->zone_list)
 332                 sseq->zone_list = publ->zone_list_next = publ;
 333         else {
 334                 publ->zone_list_next = sseq->zone_list->zone_list_next;
 335                 sseq->zone_list->zone_list_next = publ;
 336         }
 337
 338         if (in_own_cluster(node)) {
 339                 sseq->cluster_list_size++;
 340                 if (!sseq->cluster_list)
 341                         sseq->cluster_list = publ->cluster_list_next = publ;
 342                 else {
 343                         publ->cluster_list_next =
 344                         sseq->cluster_list->cluster_list_next;
 345                         sseq->cluster_list->cluster_list_next = publ;
 346                 }
 347         }
 348
 349         if (node == tipc_own_addr) {
 350                 sseq->node_list_size++;
 351                 if (!sseq->node_list)
 352                         sseq->node_list = publ->node_list_next = publ;
 353                 else {
 354                         publ->node_list_next = sseq->node_list->node_list_next;
 355                         sseq->node_list->node_list_next = publ;
 356                 }
 357         }
 358
 359         /*
 360          * Any subscriptions waiting for notification?
 361          */
 362         list_for_each_entry_safe(s, st, &nseq->subscriptions, nameseq_list) {
 363                 dbg("calling report_overlap()\n");
 364                 tipc_subscr_report_overlap(s,
 365                                            publ->lower,
 366                                            publ->upper,
 367                                            TIPC_PUBLISHED,
 368                                            publ->ref,
 369                                            publ->node,
 370                                            created_subseq);
 371         }
 372         return publ;
 373 }
 374
 375 /**
 376  * tipc_nameseq_remove_publ -
 377  *
 378  * NOTE: There may be cases where TIPC is asked to remove a publication
 379  * that is not in the name table.  For example, if another node issues a
 380  * publication for a name sequence that overlaps an existing name sequence
 381  * the publication will not be recorded, which means the publication won't
 382  * be found when the name sequence is later withdrawn by that node.
 383  * A failed withdraw request simply returns a failure indication and lets the
 384  * caller issue any error or warning messages associated with such a problem.
 385  */
 386
 387 static struct publication *tipc_nameseq_remove_publ(struct name_seq *nseq, u32 inst,
 388                                                     u32 node, u32 ref, u32 key)
 389 {
 390         struct publication *publ;
 391         struct publication *curr;
 392         struct publication *prev;
 393         struct sub_seq *sseq = nameseq_find_subseq(nseq, inst);
 394         struct sub_seq *free;
 395         struct subscription *s, *st;
 396         int removed_subseq = 0;
 397
 398         if (!sseq)
 399                 return NULL;
 400
 401         dbg("tipc_nameseq_remove_publ: seq: %p, sseq %p, {%u,%u}, key %u\n",
 402             nseq, sseq, nseq->type, inst, key);
 403
 404         /* Remove publication from zone scope list */
 405
 406         prev = sseq->zone_list;
 407         publ = sseq->zone_list->zone_list_next;
 408         while ((publ->key != key) || (publ->ref != ref) ||
 409                (publ->node && (publ->node != node))) {
 410                 prev = publ;
 411                 publ = publ->zone_list_next;
 412                 if (prev == sseq->zone_list) {
 413
 414                         /* Prevent endless loop if publication not found */
 415
 416                         return NULL;
 417                 }
 418         }
 419         if (publ != sseq->zone_list)
 420                 prev->zone_list_next = publ->zone_list_next;
 421         else if (publ->zone_list_next != publ) {
 422                 prev->zone_list_next = publ->zone_list_next;
 423                 sseq->zone_list = publ->zone_list_next;
 424         } else {
 425                 sseq->zone_list = NULL;
 426         }
 427         sseq->zone_list_size--;
 428
 429         /* Remove publication from cluster scope list, if present */
 430
 431         if (in_own_cluster(node)) {
 432                 prev = sseq->cluster_list;
 433                 curr = sseq->cluster_list->cluster_list_next;
 434                 while (curr != publ) {
 435                         prev = curr;
 436                         curr = curr->cluster_list_next;
 437                         if (prev == sseq->cluster_list) {
 438
 439                                 /* Prevent endless loop for malformed list */
 440
 441                                 err("Unable to de-list cluster publication\n"
 442                                     "{%u%u}, node=0x%x, ref=%u, key=%u)\n",
 443                                     publ->type, publ->lower, publ->node,
 444                                     publ->ref, publ->key);
 445                                 goto end_cluster;
 446                         }
 447                 }
 448                 if (publ != sseq->cluster_list)
 449                         prev->cluster_list_next = publ->cluster_list_next;
 450                 else if (publ->cluster_list_next != publ) {
 451                         prev->cluster_list_next = publ->cluster_list_next;
 452                         sseq->cluster_list = publ->cluster_list_next;
 453                 } else {
 454                         sseq->cluster_list = NULL;
 455                 }
 456                 sseq->cluster_list_size--;
 457         }
 458 end_cluster:
 459
 460         /* Remove publication from node scope list, if present */
 461
 462         if (node == tipc_own_addr) {
 463                 prev = sseq->node_list;
 464                 curr = sseq->node_list->node_list_next;
 465                 while (curr != publ) {
 466                         prev = curr;
 467                         curr = curr->node_list_next;
 468                         if (prev == sseq->node_list) {
 469
 470                                 /* Prevent endless loop for malformed list */
 471
 472                                 err("Unable to de-list node publication\n"
 473                                     "{%u%u}, node=0x%x, ref=%u, key=%u)\n",
 474                                     publ->type, publ->lower, publ->node,
 475                                     publ->ref, publ->key);
 476                                 goto end_node;
 477                         }
 478                 }
 479                 if (publ != sseq->node_list)
 480                         prev->node_list_next = publ->node_list_next;
 481                 else if (publ->node_list_next != publ) {
 482                         prev->node_list_next = publ->node_list_next;
 483                         sseq->node_list = publ->node_list_next;
 484                 } else {
 485                         sseq->node_list = NULL;
 486                 }
 487                 sseq->node_list_size--;
 488         }
 489 end_node:
 490
 491         /* Contract subseq list if no more publications for that subseq */
 492
 493         if (!sseq->zone_list) {
 494                 free = &nseq->sseqs[nseq->first_free--];
 495                 memmove(sseq, sseq + 1, (free - (sseq + 1)) * sizeof (*sseq));
 496                 removed_subseq = 1;
 497         }
 498
 499         /* Notify any waiting subscriptions */
 500
 501         list_for_each_entry_safe(s, st, &nseq->subscriptions, nameseq_list) {
 502                 tipc_subscr_report_overlap(s,
 503                                            publ->lower,
 504                                            publ->upper,
 505                                            TIPC_WITHDRAWN,
 506                                            publ->ref,
 507                                            publ->node,
 508                                            removed_subseq);
 509         }
 510
 511         return publ;
 512 }
 513
 514 /**
 515  * tipc_nameseq_subscribe: attach a subscription, and issue
 516  * the prescribed number of events if there is any sub-
 517  * sequence overlapping with the requested sequence
 518  */
 519
 520 static void tipc_nameseq_subscribe(struct name_seq *nseq, struct subscription *s)
 521 {
 522         struct sub_seq *sseq = nseq->sseqs;
 523
 524         list_add(&s->nameseq_list, &nseq->subscriptions);
 525
 526         if (!sseq)
 527                 return;
 528
 529         while (sseq != &nseq->sseqs[nseq->first_free]) {
 530                 struct publication *zl = sseq->zone_list;
 531                 if (zl && tipc_subscr_overlap(s,sseq->lower,sseq->upper)) {
 532                         struct publication *crs = zl;
 533                         int must_report = 1;
 534
 535                         do {
 536                                 tipc_subscr_report_overlap(s,
 537                                                            sseq->lower,
 538                                                            sseq->upper,
 539                                                            TIPC_PUBLISHED,
 540                                                            crs->ref,
 541                                                            crs->node,
 542                                                            must_report);
 543                                 must_report = 0;
 544                                 crs = crs->zone_list_next;
 545                         } while (crs != zl);
 546                 }
 547                 sseq++;
 548         }
 549 }
 550
 551 static struct name_seq *nametbl_find_seq(u32 type)
 552 {
 553         struct hlist_head *seq_head;
 554         struct hlist_node *seq_node;
 555         struct name_seq *ns;
 556
 557         dbg("find_seq %u,(%u,0x%x) table = %p, hash[type] = %u\n",
 558             type, ntohl(type), type, table.types, hash(type));
 559
 560         seq_head = &table.types[hash(type)];
 561         hlist_for_each_entry(ns, seq_node, seq_head, ns_list) {
 562                 if (ns->type == type) {
 563                         dbg("found %p\n", ns);
 564                         return ns;
 565                 }
 566         }
 567
 568         return NULL;
 569 };
 570
 571 struct publication *tipc_nametbl_insert_publ(u32 type, u32 lower, u32 upper,
 572                                              u32 scope, u32 node, u32 port, u32 key)
 573 {
 574         struct name_seq *seq = nametbl_find_seq(type);
 575
 576         dbg("tipc_nametbl_insert_publ: {%u,%u,%u} found %p\n", type, lower, upper, seq);
 577         if (lower > upper) {
 578                 warn("Failed to publish illegal {%u,%u,%u}\n",
 579                      type, lower, upper);
 580                 return NULL;
 581         }
 582
 583         dbg("Publishing {%u,%u,%u} from 0x%x\n", type, lower, upper, node);
 584         if (!seq) {
 585                 seq = tipc_nameseq_create(type, &table.types[hash(type)]);
 586                 dbg("tipc_nametbl_insert_publ: created %p\n", seq);
 587         }
 588         if (!seq)
 589                 return NULL;
 590
 591         return tipc_nameseq_insert_publ(seq, type, lower, upper,
 592                                         scope, node, port, key);
 593 }
 594
 595 struct publication *tipc_nametbl_remove_publ(u32 type, u32 lower,
 596                                              u32 node, u32 ref, u32 key)
 597 {
 598         struct publication *publ;
 599         struct name_seq *seq = nametbl_find_seq(type);
 600
 601         if (!seq)
 602                 return NULL;
 603
 604         dbg("Withdrawing {%u,%u} from 0x%x\n", type, lower, node);
 605         publ = tipc_nameseq_remove_publ(seq, lower, node, ref, key);
 606
 607         if (!seq->first_free && list_empty(&seq->subscriptions)) {
 608                 hlist_del_init(&seq->ns_list);
 609                 kfree(seq->sseqs);
 610                 kfree(seq);
 611         }
 612         return publ;
 613 }
 614
 615 /*
 616  * tipc_nametbl_translate(): Translate tipc_name -> tipc_portid.
 617  *                      Very time-critical.
 618  *
 619  * Note: on entry 'destnode' is the search domain used during translation;
 620  *       on exit it passes back the node address of the matching port (if any)
 621  */
 622
 623 u32 tipc_nametbl_translate(u32 type, u32 instance, u32 *destnode)
 624 {
 625         struct sub_seq *sseq;
 626         struct publication *publ = NULL;
 627         struct name_seq *seq;
 628         u32 ref;
 629
 630         if (!in_scope(*destnode, tipc_own_addr))
 631                 return 0;
 632
 633         read_lock_bh(&tipc_nametbl_lock);
 634         seq = nametbl_find_seq(type);
 635         if (unlikely(!seq))
 636                 goto not_found;
 637         sseq = nameseq_find_subseq(seq, instance);
 638         if (unlikely(!sseq))
 639                 goto not_found;
 640         spin_lock_bh(&seq->lock);
 641
 642         /* Closest-First Algorithm: */
 643         if (likely(!*destnode)) {
 644                 publ = sseq->node_list;
 645                 if (publ) {
 646                         sseq->node_list = publ->node_list_next;
 647 found:
 648                         ref = publ->ref;
 649                         *destnode = publ->node;
 650                         spin_unlock_bh(&seq->lock);
 651                         read_unlock_bh(&tipc_nametbl_lock);
 652                         return ref;
 653                 }
 654                 publ = sseq->cluster_list;
 655                 if (publ) {
 656                         sseq->cluster_list = publ->cluster_list_next;
 657                         goto found;
 658                 }
 659                 publ = sseq->zone_list;
 660                 if (publ) {
 661                         sseq->zone_list = publ->zone_list_next;
 662                         goto found;
 663                 }
 664         }
 665
 666         /* Round-Robin Algorithm: */
 667         else if (*destnode == tipc_own_addr) {
 668                 publ = sseq->node_list;
 669                 if (publ) {
 670                         sseq->node_list = publ->node_list_next;
 671                         goto found;
 672                 }
 673         } else if (in_own_cluster(*destnode)) {
 674                 publ = sseq->cluster_list;
 675                 if (publ) {
 676                         sseq->cluster_list = publ->cluster_list_next;
 677                         goto found;
 678                 }
 679         } else {
 680                 publ = sseq->zone_list;
 681                 if (publ) {
 682                         sseq->zone_list = publ->zone_list_next;
 683                         goto found;
 684                 }
 685         }
 686         spin_unlock_bh(&seq->lock);
 687 not_found:
 688         *destnode = 0;
 689         read_unlock_bh(&tipc_nametbl_lock);
 690         return 0;
 691 }
 692
 693 /**
 694  * tipc_nametbl_mc_translate - find multicast destinations
 695  *
 696  * Creates list of all local ports that overlap the given multicast address;
 697  * also determines if any off-node ports overlap.
 698  *
 699  * Note: Publications with a scope narrower than 'limit' are ignored.
 700  * (i.e. local node-scope publications mustn't receive messages arriving
 701  * from another node, even if the multcast link brought it here)
 702  *
 703  * Returns non-zero if any off-node ports overlap
 704  */
 705
 706 int tipc_nametbl_mc_translate(u32 type, u32 lower, u32 upper, u32 limit,
 707                               struct port_list *dports)
 708 {
 709         struct name_seq *seq;
 710         struct sub_seq *sseq;
 711         struct sub_seq *sseq_stop;
 712         int res = 0;
 713
 714         read_lock_bh(&tipc_nametbl_lock);
 715         seq = nametbl_find_seq(type);
 716         if (!seq)
 717                 goto exit;
 718
 719         spin_lock_bh(&seq->lock);
 720
 721         sseq = seq->sseqs + nameseq_locate_subseq(seq, lower);
 722         sseq_stop = seq->sseqs + seq->first_free;
 723         for (; sseq != sseq_stop; sseq++) {
 724                 struct publication *publ;
 725
 726                 if (sseq->lower > upper)
 727                         break;
 728
 729                 publ = sseq->node_list;
 730                 if (publ) {
 731                         do {
 732                                 if (publ->scope <= limit)
 733                                         tipc_port_list_add(dports, publ->ref);
 734                                 publ = publ->node_list_next;
 735                         } while (publ != sseq->node_list);
 736                 }
 737
 738                 if (sseq->cluster_list_size != sseq->node_list_size)
 739                         res = 1;
 740         }
 741
 742         spin_unlock_bh(&seq->lock);
 743 exit:
 744         read_unlock_bh(&tipc_nametbl_lock);
 745         return res;
 746 }
 747
 748 /**
 749  * tipc_nametbl_publish_rsv - publish port name using a reserved name type
 750  */
 751
 752 int tipc_nametbl_publish_rsv(u32 ref, unsigned int scope,
 753                         struct tipc_name_seq const *seq)
 754 {
 755         int res;
 756
 757         atomic_inc(&rsv_publ_ok);
 758         res = tipc_publish(ref, scope, seq);
 759         atomic_dec(&rsv_publ_ok);
 760         return res;
 761 }
 762
 763 /**
 764  * tipc_nametbl_publish - add name publication to network name tables
 765  */
 766
 767 struct publication *tipc_nametbl_publish(u32 type, u32 lower, u32 upper,
 768                                     u32 scope, u32 port_ref, u32 key)
 769 {
 770         struct publication *publ;
 771
 772         if (table.local_publ_count >= tipc_max_publications) {
 773                 warn("Publication failed, local publication limit reached (%u)\n",
 774                      tipc_max_publications);
 775                 return NULL;
 776         }
 777         if ((type < TIPC_RESERVED_TYPES) && !atomic_read(&rsv_publ_ok)) {
 778                 warn("Publication failed, reserved name {%u,%u,%u}\n",
 779                      type, lower, upper);
 780                 return NULL;
 781         }
 782
 783         write_lock_bh(&tipc_nametbl_lock);
 784         table.local_publ_count++;
 785         publ = tipc_nametbl_insert_publ(type, lower, upper, scope,
 786                                    tipc_own_addr, port_ref, key);
 787         if (publ && (scope != TIPC_NODE_SCOPE)) {
 788                 tipc_named_publish(publ);
 789         }
 790         write_unlock_bh(&tipc_nametbl_lock);
 791         return publ;
 792 }
 793
 794 /**
 795  * tipc_nametbl_withdraw - withdraw name publication from network name tables
 796  */
 797
 798 int tipc_nametbl_withdraw(u32 type, u32 lower, u32 ref, u32 key)
 799 {
 800         struct publication *publ;
 801
 802         dbg("tipc_nametbl_withdraw: {%u,%u}, key=%u\n", type, lower, key);
 803         write_lock_bh(&tipc_nametbl_lock);
 804         publ = tipc_nametbl_remove_publ(type, lower, tipc_own_addr, ref, key);
 805         if (likely(publ)) {
 806                 table.local_publ_count--;
 807                 if (publ->scope != TIPC_NODE_SCOPE)
 808                         tipc_named_withdraw(publ);
 809                 write_unlock_bh(&tipc_nametbl_lock);
 810                 list_del_init(&publ->pport_list);
 811                 kfree(publ);
 812                 return 1;
 813         }
 814         write_unlock_bh(&tipc_nametbl_lock);
 815         err("Unable to remove local publication\n"
 816             "(type=%u, lower=%u, ref=%u, key=%u)\n",
 817             type, lower, ref, key);
 818         return 0;
 819 }
 820
 821 /**
 822  * tipc_nametbl_subscribe - add a subscription object to the name table
 823  */
 824
 825 void tipc_nametbl_subscribe(struct subscription *s)
 826 {
 827         u32 type = s->seq.type;
 828         struct name_seq *seq;
 829
 830         write_lock_bh(&tipc_nametbl_lock);
 831         seq = nametbl_find_seq(type);
 832         if (!seq) {
 833                 seq = tipc_nameseq_create(type, &table.types[hash(type)]);
 834         }
 835         if (seq){
 836                 spin_lock_bh(&seq->lock);
 837                 dbg("tipc_nametbl_subscribe:found %p for {%u,%u,%u}\n",
 838                     seq, type, s->seq.lower, s->seq.upper);
 839                 tipc_nameseq_subscribe(seq, s);
 840                 spin_unlock_bh(&seq->lock);
 841         } else {
 842                 warn("Failed to create subscription for {%u,%u,%u}\n",
 843                      s->seq.type, s->seq.lower, s->seq.upper);
 844         }
 845         write_unlock_bh(&tipc_nametbl_lock);
 846 }
 847
 848 /**
 849  * tipc_nametbl_unsubscribe - remove a subscription object from name table
 850  */
 851
 852 void tipc_nametbl_unsubscribe(struct subscription *s)
 853 {
 854         struct name_seq *seq;
 855
 856         write_lock_bh(&tipc_nametbl_lock);
 857         seq = nametbl_find_seq(s->seq.type);
 858         if (seq != NULL){
 859                 spin_lock_bh(&seq->lock);
 860                 list_del_init(&s->nameseq_list);
 861                 spin_unlock_bh(&seq->lock);
 862                 if ((seq->first_free == 0) && list_empty(&seq->subscriptions)) {
 863                         hlist_del_init(&seq->ns_list);
 864                         kfree(seq->sseqs);
 865                         kfree(seq);
 866                 }
 867         }
 868         write_unlock_bh(&tipc_nametbl_lock);
 869 }
 870
 871
 872 /**
 873  * subseq_list: print specified sub-sequence contents into the given buffer
 874  */
 875
 876 static void subseq_list(struct sub_seq *sseq, struct print_buf *buf, u32 depth,
 877                         u32 index)
 878 {
 879         char portIdStr[27];
 880         char *scopeStr;
 881         struct publication *publ = sseq->zone_list;
 882
 883         tipc_printf(buf, "%-10u %-10u ", sseq->lower, sseq->upper);
 884
 885         if (depth == 2 || !publ) {
 886                 tipc_printf(buf, "\n");
 887                 return;
 888         }
 889
 890         do {
 891                 sprintf (portIdStr, "<%u.%u.%u:%u>",
 892                          tipc_zone(publ->node), tipc_cluster(publ->node),
 893                          tipc_node(publ->node), publ->ref);
 894                 tipc_printf(buf, "%-26s ", portIdStr);
 895                 if (depth > 3) {
 896                         if (publ->node != tipc_own_addr)
 897                                 scopeStr = "";
 898                         else if (publ->scope == TIPC_NODE_SCOPE)
 899                                 scopeStr = "node";
 900                         else if (publ->scope == TIPC_CLUSTER_SCOPE)
 901                                 scopeStr = "cluster";
 902                         else
 903                                 scopeStr = "zone";
 904                         tipc_printf(buf, "%-10u %s", publ->key, scopeStr);
 905                 }
 906
 907                 publ = publ->zone_list_next;
 908                 if (publ == sseq->zone_list)
 909                         break;
 910
 911                 tipc_printf(buf, "\n%33s", " ");
 912         } while (1);
 913
 914         tipc_printf(buf, "\n");
 915 }
 916
 917 /**
 918  * nameseq_list: print specified name sequence contents into the given buffer
 919  */
 920
 921 static void nameseq_list(struct name_seq *seq, struct print_buf *buf, u32 depth,
 922                          u32 type, u32 lowbound, u32 upbound, u32 index)
 923 {
 924         struct sub_seq *sseq;
 925         char typearea[11];
 926
 927         if (seq->first_free == 0)
 928                 return;
 929
 930         sprintf(typearea, "%-10u", seq->type);
 931
 932         if (depth == 1) {
 933                 tipc_printf(buf, "%s\n", typearea);
 934                 return;
 935         }
 936
 937         for (sseq = seq->sseqs; sseq != &seq->sseqs[seq->first_free]; sseq++) {
 938                 if ((lowbound <= sseq->upper) && (upbound >= sseq->lower)) {
 939                         tipc_printf(buf, "%s ", typearea);
 940                         spin_lock_bh(&seq->lock);
 941                         subseq_list(sseq, buf, depth, index);
 942                         spin_unlock_bh(&seq->lock);
 943                         sprintf(typearea, "%10s", " ");
 944                 }
 945         }
 946 }
 947
 948 /**
 949  * nametbl_header - print name table header into the given buffer
 950  */
 951
 952 static void nametbl_header(struct print_buf *buf, u32 depth)
 953 {
 954         tipc_printf(buf, "Type       ");
 955
 956         if (depth > 1)
 957                 tipc_printf(buf, "Lower      Upper      ");
 958         if (depth > 2)
 959                 tipc_printf(buf, "Port Identity              ");
 960         if (depth > 3)
 961                 tipc_printf(buf, "Publication");
 962
 963         tipc_printf(buf, "\n-----------");
 964
 965         if (depth > 1)
 966                 tipc_printf(buf, "--------------------- ");
 967         if (depth > 2)
 968                 tipc_printf(buf, "-------------------------- ");
 969         if (depth > 3)
 970                 tipc_printf(buf, "------------------");
 971
 972         tipc_printf(buf, "\n");
 973 }
 974
 975 /**
 976  * nametbl_list - print specified name table contents into the given buffer
 977  */
 978
 979 static void nametbl_list(struct print_buf *buf, u32 depth_info,
 980                          u32 type, u32 lowbound, u32 upbound)
 981 {
 982         struct hlist_head *seq_head;
 983         struct hlist_node *seq_node;
 984         struct name_seq *seq;
 985         int all_types;
 986         u32 depth;
 987         u32 i;
 988
 989         all_types = (depth_info & TIPC_NTQ_ALLTYPES);
 990         depth = (depth_info & ~TIPC_NTQ_ALLTYPES);
 991
 992         if (depth == 0)
 993                 return;
 994
 995         if (all_types) {
 996                 /* display all entries in name table to specified depth */
 997                 nametbl_header(buf, depth);
 998                 lowbound = 0;
 999                 upbound = ~0;
1000                 for (i = 0; i < tipc_nametbl_size; i++) {
1001                         seq_head = &table.types[i];
1002                         hlist_for_each_entry(seq, seq_node, seq_head, ns_list) {
1003                                 nameseq_list(seq, buf, depth, seq->type,
1004                                              lowbound, upbound, i);
1005                         }
1006                 }
1007         } else {
1008                 /* display only the sequence that matches the specified type */
1009                 if (upbound < lowbound) {
1010                         tipc_printf(buf, "invalid name sequence specified\n");
1011                         return;
1012                 }
1013                 nametbl_header(buf, depth);
1014                 i = hash(type);
1015                 seq_head = &table.types[i];
1016                 hlist_for_each_entry(seq, seq_node, seq_head, ns_list) {
1017                         if (seq->type == type) {
1018                                 nameseq_list(seq, buf, depth, type,
1019                                              lowbound, upbound, i);
1020                                 break;
1021                         }
1022                 }
1023         }
1024 }
1025
1026 #if 0
1027 void tipc_nametbl_print(struct print_buf *buf, const char *str)
1028 {
1029         tipc_printf(buf, str);
1030         read_lock_bh(&tipc_nametbl_lock);
1031         nametbl_list(buf, 0, 0, 0, 0);
1032         read_unlock_bh(&tipc_nametbl_lock);
1033 }
1034 #endif
1035
1036 #define MAX_NAME_TBL_QUERY 32768
1037
1038 struct sk_buff *tipc_nametbl_get(const void *req_tlv_area, int req_tlv_space)
1039 {
1040         struct sk_buff *buf;
1041         struct tipc_name_table_query *argv;
1042         struct tlv_desc *rep_tlv;
1043         struct print_buf b;
1044         int str_len;
1045
1046         if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NAME_TBL_QUERY))
1047                 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
1048
1049         buf = tipc_cfg_reply_alloc(TLV_SPACE(MAX_NAME_TBL_QUERY));
1050         if (!buf)
1051                 return NULL;
1052
1053         rep_tlv = (struct tlv_desc *)buf->data;
1054         tipc_printbuf_init(&b, TLV_DATA(rep_tlv), MAX_NAME_TBL_QUERY);
1055         argv = (struct tipc_name_table_query *)TLV_DATA(req_tlv_area);
1056         read_lock_bh(&tipc_nametbl_lock);
1057         nametbl_list(&b, ntohl(argv->depth), ntohl(argv->type),
1058                      ntohl(argv->lowbound), ntohl(argv->upbound));
1059         read_unlock_bh(&tipc_nametbl_lock);
1060         str_len = tipc_printbuf_validate(&b);
1061
1062         skb_put(buf, TLV_SPACE(str_len));
1063         TLV_SET(rep_tlv, TIPC_TLV_ULTRA_STRING, NULL, str_len);
1064
1065         return buf;
1066 }
1067
1068 #if 0
1069 void tipc_nametbl_dump(void)
1070 {
1071         nametbl_list(TIPC_CONS, 0, 0, 0, 0);
1072 }
1073 #endif
1074
1075 int tipc_nametbl_init(void)
1076 {
1077         table.types = kcalloc(tipc_nametbl_size, sizeof(struct hlist_head),
1078                               GFP_ATOMIC);
1079         if (!table.types)
1080                 return -ENOMEM;
1081
1082         table.local_publ_count = 0;
1083         return 0;
1084 }
1085
1086 void tipc_nametbl_stop(void)
1087 {
1088         u32 i;
1089
1090         if (!table.types)
1091                 return;
1092
1093         /* Verify name table is empty, then release it */
1094
1095         write_lock_bh(&tipc_nametbl_lock);
1096         for (i = 0; i < tipc_nametbl_size; i++) {
1097                 if (!hlist_empty(&table.types[i]))
1098                         err("tipc_nametbl_stop(): hash chain %u is non-null\n", i);
1099         }
1100         kfree(table.types);
1101         table.types = NULL;
1102         write_unlock_bh(&tipc_nametbl_lock);
1103 }
1104