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, htonl(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 name to port id
 617  *
 618  * Note: on entry 'destnode' is the search domain used during translation;
 619  *       on exit it passes back the node address of the matching port (if any)
 620  */
 621
 622 u32 tipc_nametbl_translate(u32 type, u32 instance, u32 *destnode)
 623 {
 624         struct sub_seq *sseq;
 625         struct publication *publ = NULL;
 626         struct name_seq *seq;
 627         u32 ref;
 628
 629         if (!tipc_in_scope(*destnode, tipc_own_addr))
 630                 return 0;
 631
 632         read_lock_bh(&tipc_nametbl_lock);
 633         seq = nametbl_find_seq(type);
 634         if (unlikely(!seq))
 635                 goto not_found;
 636         sseq = nameseq_find_subseq(seq, instance);
 637         if (unlikely(!sseq))
 638                 goto not_found;
 639         spin_lock_bh(&seq->lock);
 640
 641         /* Closest-First Algorithm: */
 642         if (likely(!*destnode)) {
 643                 publ = sseq->node_list;
 644                 if (publ) {
 645                         sseq->node_list = publ->node_list_next;
 646 found:
 647                         ref = publ->ref;
 648                         *destnode = publ->node;
 649                         spin_unlock_bh(&seq->lock);
 650                         read_unlock_bh(&tipc_nametbl_lock);
 651                         return ref;
 652                 }
 653                 publ = sseq->cluster_list;
 654                 if (publ) {
 655                         sseq->cluster_list = publ->cluster_list_next;
 656                         goto found;
 657                 }
 658                 publ = sseq->zone_list;
 659                 if (publ) {
 660                         sseq->zone_list = publ->zone_list_next;
 661                         goto found;
 662                 }
 663         }
 664
 665         /* Round-Robin Algorithm: */
 666         else if (*destnode == tipc_own_addr) {
 667                 publ = sseq->node_list;
 668                 if (publ) {
 669                         sseq->node_list = publ->node_list_next;
 670                         goto found;
 671                 }
 672         } else if (in_own_cluster(*destnode)) {
 673                 publ = sseq->cluster_list;
 674                 if (publ) {
 675                         sseq->cluster_list = publ->cluster_list_next;
 676                         goto found;
 677                 }
 678         } else {
 679                 publ = sseq->zone_list;
 680                 if (publ) {
 681                         sseq->zone_list = publ->zone_list_next;
 682                         goto found;
 683                 }
 684         }
 685         spin_unlock_bh(&seq->lock);
 686 not_found:
 687         read_unlock_bh(&tipc_nametbl_lock);
 688         return 0;
 689 }
 690
 691 /**
 692  * tipc_nametbl_mc_translate - find multicast destinations
 693  *
 694  * Creates list of all local ports that overlap the given multicast address;
 695  * also determines if any off-node ports overlap.
 696  *
 697  * Note: Publications with a scope narrower than 'limit' are ignored.
 698  * (i.e. local node-scope publications mustn't receive messages arriving
 699  * from another node, even if the multcast link brought it here)
 700  *
 701  * Returns non-zero if any off-node ports overlap
 702  */
 703
 704 int tipc_nametbl_mc_translate(u32 type, u32 lower, u32 upper, u32 limit,
 705                               struct port_list *dports)
 706 {
 707         struct name_seq *seq;
 708         struct sub_seq *sseq;
 709         struct sub_seq *sseq_stop;
 710         int res = 0;
 711
 712         read_lock_bh(&tipc_nametbl_lock);
 713         seq = nametbl_find_seq(type);
 714         if (!seq)
 715                 goto exit;
 716
 717         spin_lock_bh(&seq->lock);
 718
 719         sseq = seq->sseqs + nameseq_locate_subseq(seq, lower);
 720         sseq_stop = seq->sseqs + seq->first_free;
 721         for (; sseq != sseq_stop; sseq++) {
 722                 struct publication *publ;
 723
 724                 if (sseq->lower > upper)
 725                         break;
 726
 727                 publ = sseq->node_list;
 728                 if (publ) {
 729                         do {
 730                                 if (publ->scope <= limit)
 731                                         tipc_port_list_add(dports, publ->ref);
 732                                 publ = publ->node_list_next;
 733                         } while (publ != sseq->node_list);
 734                 }
 735
 736                 if (sseq->cluster_list_size != sseq->node_list_size)
 737                         res = 1;
 738         }
 739
 740         spin_unlock_bh(&seq->lock);
 741 exit:
 742         read_unlock_bh(&tipc_nametbl_lock);
 743         return res;
 744 }
 745
 746 /**
 747  * tipc_nametbl_publish_rsv - publish port name using a reserved name type
 748  */
 749
 750 int tipc_nametbl_publish_rsv(u32 ref, unsigned int scope,
 751                         struct tipc_name_seq const *seq)
 752 {
 753         int res;
 754
 755         atomic_inc(&rsv_publ_ok);
 756         res = tipc_publish(ref, scope, seq);
 757         atomic_dec(&rsv_publ_ok);
 758         return res;
 759 }
 760
 761 /**
 762  * tipc_nametbl_publish - add name publication to network name tables
 763  */
 764
 765 struct publication *tipc_nametbl_publish(u32 type, u32 lower, u32 upper,
 766                                     u32 scope, u32 port_ref, u32 key)
 767 {
 768         struct publication *publ;
 769
 770         if (table.local_publ_count >= tipc_max_publications) {
 771                 warn("Publication failed, local publication limit reached (%u)\n",
 772                      tipc_max_publications);
 773                 return NULL;
 774         }
 775         if ((type < TIPC_RESERVED_TYPES) && !atomic_read(&rsv_publ_ok)) {
 776                 warn("Publication failed, reserved name {%u,%u,%u}\n",
 777                      type, lower, upper);
 778                 return NULL;
 779         }
 780
 781         write_lock_bh(&tipc_nametbl_lock);
 782         table.local_publ_count++;
 783         publ = tipc_nametbl_insert_publ(type, lower, upper, scope,
 784                                    tipc_own_addr, port_ref, key);
 785         if (publ && (scope != TIPC_NODE_SCOPE)) {
 786                 tipc_named_publish(publ);
 787         }
 788         write_unlock_bh(&tipc_nametbl_lock);
 789         return publ;
 790 }
 791
 792 /**
 793  * tipc_nametbl_withdraw - withdraw name publication from network name tables
 794  */
 795
 796 int tipc_nametbl_withdraw(u32 type, u32 lower, u32 ref, u32 key)
 797 {
 798         struct publication *publ;
 799
 800         dbg("tipc_nametbl_withdraw: {%u,%u}, key=%u\n", type, lower, key);
 801         write_lock_bh(&tipc_nametbl_lock);
 802         publ = tipc_nametbl_remove_publ(type, lower, tipc_own_addr, ref, key);
 803         if (likely(publ)) {
 804                 table.local_publ_count--;
 805                 if (publ->scope != TIPC_NODE_SCOPE)
 806                         tipc_named_withdraw(publ);
 807                 write_unlock_bh(&tipc_nametbl_lock);
 808                 list_del_init(&publ->pport_list);
 809                 kfree(publ);
 810                 return 1;
 811         }
 812         write_unlock_bh(&tipc_nametbl_lock);
 813         err("Unable to remove local publication\n"
 814             "(type=%u, lower=%u, ref=%u, key=%u)\n",
 815             type, lower, ref, key);
 816         return 0;
 817 }
 818
 819 /**
 820  * tipc_nametbl_subscribe - add a subscription object to the name table
 821  */
 822
 823 void tipc_nametbl_subscribe(struct subscription *s)
 824 {
 825         u32 type = s->seq.type;
 826         struct name_seq *seq;
 827
 828         write_lock_bh(&tipc_nametbl_lock);
 829         seq = nametbl_find_seq(type);
 830         if (!seq) {
 831                 seq = tipc_nameseq_create(type, &table.types[hash(type)]);
 832         }
 833         if (seq){
 834                 spin_lock_bh(&seq->lock);
 835                 dbg("tipc_nametbl_subscribe:found %p for {%u,%u,%u}\n",
 836                     seq, type, s->seq.lower, s->seq.upper);
 837                 tipc_nameseq_subscribe(seq, s);
 838                 spin_unlock_bh(&seq->lock);
 839         } else {
 840                 warn("Failed to create subscription for {%u,%u,%u}\n",
 841                      s->seq.type, s->seq.lower, s->seq.upper);
 842         }
 843         write_unlock_bh(&tipc_nametbl_lock);
 844 }
 845
 846 /**
 847  * tipc_nametbl_unsubscribe - remove a subscription object from name table
 848  */
 849
 850 void tipc_nametbl_unsubscribe(struct subscription *s)
 851 {
 852         struct name_seq *seq;
 853
 854         write_lock_bh(&tipc_nametbl_lock);
 855         seq = nametbl_find_seq(s->seq.type);
 856         if (seq != NULL){
 857                 spin_lock_bh(&seq->lock);
 858                 list_del_init(&s->nameseq_list);
 859                 spin_unlock_bh(&seq->lock);
 860                 if ((seq->first_free == 0) && list_empty(&seq->subscriptions)) {
 861                         hlist_del_init(&seq->ns_list);
 862                         kfree(seq->sseqs);
 863                         kfree(seq);
 864                 }
 865         }
 866         write_unlock_bh(&tipc_nametbl_lock);
 867 }
 868
 869
 870 /**
 871  * subseq_list: print specified sub-sequence contents into the given buffer
 872  */
 873
 874 static void subseq_list(struct sub_seq *sseq, struct print_buf *buf, u32 depth,
 875                         u32 index)
 876 {
 877         char portIdStr[27];
 878         const char *scope_str[] = {"", " zone", " cluster", " node"};
 879         struct publication *publ = sseq->zone_list;
 880
 881         tipc_printf(buf, "%-10u %-10u ", sseq->lower, sseq->upper);
 882
 883         if (depth == 2 || !publ) {
 884                 tipc_printf(buf, "\n");
 885                 return;
 886         }
 887
 888         do {
 889                 sprintf (portIdStr, "<%u.%u.%u:%u>",
 890                          tipc_zone(publ->node), tipc_cluster(publ->node),
 891                          tipc_node(publ->node), publ->ref);
 892                 tipc_printf(buf, "%-26s ", portIdStr);
 893                 if (depth > 3) {
 894                         tipc_printf(buf, "%-10u %s", publ->key,
 895                                     scope_str[publ->scope]);
 896                 }
 897
 898                 publ = publ->zone_list_next;
 899                 if (publ == sseq->zone_list)
 900                         break;
 901
 902                 tipc_printf(buf, "\n%33s", " ");
 903         } while (1);
 904
 905         tipc_printf(buf, "\n");
 906 }
 907
 908 /**
 909  * nameseq_list: print specified name sequence contents into the given buffer
 910  */
 911
 912 static void nameseq_list(struct name_seq *seq, struct print_buf *buf, u32 depth,
 913                          u32 type, u32 lowbound, u32 upbound, u32 index)
 914 {
 915         struct sub_seq *sseq;
 916         char typearea[11];
 917
 918         if (seq->first_free == 0)
 919                 return;
 920
 921         sprintf(typearea, "%-10u", seq->type);
 922
 923         if (depth == 1) {
 924                 tipc_printf(buf, "%s\n", typearea);
 925                 return;
 926         }
 927
 928         for (sseq = seq->sseqs; sseq != &seq->sseqs[seq->first_free]; sseq++) {
 929                 if ((lowbound <= sseq->upper) && (upbound >= sseq->lower)) {
 930                         tipc_printf(buf, "%s ", typearea);
 931                         spin_lock_bh(&seq->lock);
 932                         subseq_list(sseq, buf, depth, index);
 933                         spin_unlock_bh(&seq->lock);
 934                         sprintf(typearea, "%10s", " ");
 935                 }
 936         }
 937 }
 938
 939 /**
 940  * nametbl_header - print name table header into the given buffer
 941  */
 942
 943 static void nametbl_header(struct print_buf *buf, u32 depth)
 944 {
 945         const char *header[] = {
 946                 "Type       ",
 947                 "Lower      Upper      ",
 948                 "Port Identity              ",
 949                 "Publication Scope"
 950         };
 951
 952         int i;
 953
 954         if (depth > 4)
 955                 depth = 4;
 956         for (i = 0; i < depth; i++)
 957                 tipc_printf(buf, header[i]);
 958         tipc_printf(buf, "\n");
 959 }
 960
 961 /**
 962  * nametbl_list - print specified name table contents into the given buffer
 963  */
 964
 965 static void nametbl_list(struct print_buf *buf, u32 depth_info,
 966                          u32 type, u32 lowbound, u32 upbound)
 967 {
 968         struct hlist_head *seq_head;
 969         struct hlist_node *seq_node;
 970         struct name_seq *seq;
 971         int all_types;
 972         u32 depth;
 973         u32 i;
 974
 975         all_types = (depth_info & TIPC_NTQ_ALLTYPES);
 976         depth = (depth_info & ~TIPC_NTQ_ALLTYPES);
 977
 978         if (depth == 0)
 979                 return;
 980
 981         if (all_types) {
 982                 /* display all entries in name table to specified depth */
 983                 nametbl_header(buf, depth);
 984                 lowbound = 0;
 985                 upbound = ~0;
 986                 for (i = 0; i < tipc_nametbl_size; i++) {
 987                         seq_head = &table.types[i];
 988                         hlist_for_each_entry(seq, seq_node, seq_head, ns_list) {
 989                                 nameseq_list(seq, buf, depth, seq->type,
 990                                              lowbound, upbound, i);
 991                         }
 992                 }
 993         } else {
 994                 /* display only the sequence that matches the specified type */
 995                 if (upbound < lowbound) {
 996                         tipc_printf(buf, "invalid name sequence specified\n");
 997                         return;
 998                 }
 999                 nametbl_header(buf, depth);
1000                 i = hash(type);
1001                 seq_head = &table.types[i];
1002                 hlist_for_each_entry(seq, seq_node, seq_head, ns_list) {
1003                         if (seq->type == type) {
1004                                 nameseq_list(seq, buf, depth, type,
1005                                              lowbound, upbound, i);
1006                                 break;
1007                         }
1008                 }
1009         }
1010 }
1011
1012 #define MAX_NAME_TBL_QUERY 32768
1013
1014 struct sk_buff *tipc_nametbl_get(const void *req_tlv_area, int req_tlv_space)
1015 {
1016         struct sk_buff *buf;
1017         struct tipc_name_table_query *argv;
1018         struct tlv_desc *rep_tlv;
1019         struct print_buf b;
1020         int str_len;
1021
1022         if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NAME_TBL_QUERY))
1023                 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
1024
1025         buf = tipc_cfg_reply_alloc(TLV_SPACE(MAX_NAME_TBL_QUERY));
1026         if (!buf)
1027                 return NULL;
1028
1029         rep_tlv = (struct tlv_desc *)buf->data;
1030         tipc_printbuf_init(&b, TLV_DATA(rep_tlv), MAX_NAME_TBL_QUERY);
1031         argv = (struct tipc_name_table_query *)TLV_DATA(req_tlv_area);
1032         read_lock_bh(&tipc_nametbl_lock);
1033         nametbl_list(&b, ntohl(argv->depth), ntohl(argv->type),
1034                      ntohl(argv->lowbound), ntohl(argv->upbound));
1035         read_unlock_bh(&tipc_nametbl_lock);
1036         str_len = tipc_printbuf_validate(&b);
1037
1038         skb_put(buf, TLV_SPACE(str_len));
1039         TLV_SET(rep_tlv, TIPC_TLV_ULTRA_STRING, NULL, str_len);
1040
1041         return buf;
1042 }
1043
1044 int tipc_nametbl_init(void)
1045 {
1046         table.types = kcalloc(tipc_nametbl_size, sizeof(struct hlist_head),
1047                               GFP_ATOMIC);
1048         if (!table.types)
1049                 return -ENOMEM;
1050
1051         table.local_publ_count = 0;
1052         return 0;
1053 }
1054
1055 void tipc_nametbl_stop(void)
1056 {
1057         u32 i;
1058
1059         if (!table.types)
1060                 return;
1061
1062         /* Verify name table is empty, then release it */
1063
1064         write_lock_bh(&tipc_nametbl_lock);
1065         for (i = 0; i < tipc_nametbl_size; i++) {
1066                 if (!hlist_empty(&table.types[i]))
1067                         err("tipc_nametbl_stop(): hash chain %u is non-null\n", i);
1068         }
1069         kfree(table.types);
1070         table.types = NULL;
1071         write_unlock_bh(&tipc_nametbl_lock);
1072 }
1073