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, 2010-2011, 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 "name_table.h"
  40 #include "name_distr.h"
  41 #include "subscr.h"
  42 #include "port.h"
  43
  44 static int tipc_nametbl_size = 1024;            /* must be a power of 2 */
  45
  46 /**
  47  * struct name_info - name sequence publication info
  48  * @node_list: circular list of publications made by own node
  49  * @cluster_list: circular list of publications made by own cluster
  50  * @zone_list: circular list of publications made by own zone
  51  * @node_list_size: number of entries in "node_list"
  52  * @cluster_list_size: number of entries in "cluster_list"
  53  * @zone_list_size: number of entries in "zone_list"
  54  *
  55  * Note: The zone list always contains at least one entry, since all
  56  *       publications of the associated name sequence belong to it.
  57  *       (The cluster and node lists may be empty.)
  58  */
  59
  60 struct name_info {
  61         struct list_head node_list;
  62         struct list_head cluster_list;
  63         struct list_head zone_list;
  64         u32 node_list_size;
  65         u32 cluster_list_size;
  66         u32 zone_list_size;
  67 };
  68
  69 /**
  70  * struct sub_seq - container for all published instances of a name sequence
  71  * @lower: name sequence lower bound
  72  * @upper: name sequence upper bound
  73  * @info: pointer to name sequence publication info
  74  */
  75
  76 struct sub_seq {
  77         u32 lower;
  78         u32 upper;
  79         struct name_info *info;
  80 };
  81
  82 /**
  83  * struct name_seq - container for all published instances of a name type
  84  * @type: 32 bit 'type' value for name sequence
  85  * @sseq: pointer to dynamically-sized array of sub-sequences of this 'type';
  86  *        sub-sequences are sorted in ascending order
  87  * @alloc: number of sub-sequences currently in array
  88  * @first_free: array index of first unused sub-sequence entry
  89  * @ns_list: links to adjacent name sequences in hash chain
  90  * @subscriptions: list of subscriptions for this 'type'
  91  * @lock: spinlock controlling access to publication lists of all sub-sequences
  92  */
  93
  94 struct name_seq {
  95         u32 type;
  96         struct sub_seq *sseqs;
  97         u32 alloc;
  98         u32 first_free;
  99         struct hlist_node ns_list;
 100         struct list_head subscriptions;
 101         spinlock_t lock;
 102 };
 103
 104 /**
 105  * struct name_table - table containing all existing port name publications
 106  * @types: pointer to fixed-sized array of name sequence lists,
 107  *         accessed via hashing on 'type'; name sequence lists are *not* sorted
 108  * @local_publ_count: number of publications issued by this node
 109  */
 110
 111 struct name_table {
 112         struct hlist_head *types;
 113         u32 local_publ_count;
 114 };
 115
 116 static struct name_table table;
 117 static atomic_t rsv_publ_ok = ATOMIC_INIT(0);
 118 DEFINE_RWLOCK(tipc_nametbl_lock);
 119
 120
 121 static int hash(int x)
 122 {
 123         return x & (tipc_nametbl_size - 1);
 124 }
 125
 126 /**
 127  * publ_create - create a publication structure
 128  */
 129
 130 static struct publication *publ_create(u32 type, u32 lower, u32 upper,
 131                                        u32 scope, u32 node, u32 port_ref,
 132                                        u32 key)
 133 {
 134         struct publication *publ = kzalloc(sizeof(*publ), GFP_ATOMIC);
 135         if (publ == NULL) {
 136                 warn("Publication creation failure, no memory\n");
 137                 return NULL;
 138         }
 139
 140         publ->type = type;
 141         publ->lower = lower;
 142         publ->upper = upper;
 143         publ->scope = scope;
 144         publ->node = node;
 145         publ->ref = port_ref;
 146         publ->key = key;
 147         INIT_LIST_HEAD(&publ->local_list);
 148         INIT_LIST_HEAD(&publ->pport_list);
 149         INIT_LIST_HEAD(&publ->subscr.nodesub_list);
 150         return publ;
 151 }
 152
 153 /**
 154  * tipc_subseq_alloc - allocate a specified number of sub-sequence structures
 155  */
 156
 157 static struct sub_seq *tipc_subseq_alloc(u32 cnt)
 158 {
 159         struct sub_seq *sseq = kcalloc(cnt, sizeof(struct sub_seq), GFP_ATOMIC);
 160         return sseq;
 161 }
 162
 163 /**
 164  * tipc_nameseq_create - create a name sequence structure for the specified 'type'
 165  *
 166  * Allocates a single sub-sequence structure and sets it to all 0's.
 167  */
 168
 169 static struct name_seq *tipc_nameseq_create(u32 type, struct hlist_head *seq_head)
 170 {
 171         struct name_seq *nseq = kzalloc(sizeof(*nseq), GFP_ATOMIC);
 172         struct sub_seq *sseq = tipc_subseq_alloc(1);
 173
 174         if (!nseq || !sseq) {
 175                 warn("Name sequence creation failed, no memory\n");
 176                 kfree(nseq);
 177                 kfree(sseq);
 178                 return NULL;
 179         }
 180
 181         spin_lock_init(&nseq->lock);
 182         nseq->type = type;
 183         nseq->sseqs = sseq;
 184         nseq->alloc = 1;
 185         INIT_HLIST_NODE(&nseq->ns_list);
 186         INIT_LIST_HEAD(&nseq->subscriptions);
 187         hlist_add_head(&nseq->ns_list, seq_head);
 188         return nseq;
 189 }
 190
 191 /**
 192  * nameseq_find_subseq - find sub-sequence (if any) matching a name instance
 193  *
 194  * Very time-critical, so binary searches through sub-sequence array.
 195  */
 196
 197 static struct sub_seq *nameseq_find_subseq(struct name_seq *nseq,
 198                                            u32 instance)
 199 {
 200         struct sub_seq *sseqs = nseq->sseqs;
 201         int low = 0;
 202         int high = nseq->first_free - 1;
 203         int mid;
 204
 205         while (low <= high) {
 206                 mid = (low + high) / 2;
 207                 if (instance < sseqs[mid].lower)
 208                         high = mid - 1;
 209                 else if (instance > sseqs[mid].upper)
 210                         low = mid + 1;
 211                 else
 212                         return &sseqs[mid];
 213         }
 214         return NULL;
 215 }
 216
 217 /**
 218  * nameseq_locate_subseq - determine position of name instance in sub-sequence
 219  *
 220  * Returns index in sub-sequence array of the entry that contains the specified
 221  * instance value; if no entry contains that value, returns the position
 222  * where a new entry for it would be inserted in the array.
 223  *
 224  * Note: Similar to binary search code for locating a sub-sequence.
 225  */
 226
 227 static u32 nameseq_locate_subseq(struct name_seq *nseq, u32 instance)
 228 {
 229         struct sub_seq *sseqs = nseq->sseqs;
 230         int low = 0;
 231         int high = nseq->first_free - 1;
 232         int mid;
 233
 234         while (low <= high) {
 235                 mid = (low + high) / 2;
 236                 if (instance < sseqs[mid].lower)
 237                         high = mid - 1;
 238                 else if (instance > sseqs[mid].upper)
 239                         low = mid + 1;
 240                 else
 241                         return mid;
 242         }
 243         return low;
 244 }
 245
 246 /**
 247  * tipc_nameseq_insert_publ -
 248  */
 249
 250 static struct publication *tipc_nameseq_insert_publ(struct name_seq *nseq,
 251                                                     u32 type, u32 lower, u32 upper,
 252                                                     u32 scope, u32 node, u32 port, u32 key)
 253 {
 254         struct tipc_subscription *s;
 255         struct tipc_subscription *st;
 256         struct publication *publ;
 257         struct sub_seq *sseq;
 258         struct name_info *info;
 259         int created_subseq = 0;
 260
 261         sseq = nameseq_find_subseq(nseq, lower);
 262         if (sseq) {
 263
 264                 /* Lower end overlaps existing entry => need an exact match */
 265
 266                 if ((sseq->lower != lower) || (sseq->upper != upper)) {
 267                         warn("Cannot publish {%u,%u,%u}, overlap error\n",
 268                              type, lower, upper);
 269                         return NULL;
 270                 }
 271
 272                 info = sseq->info;
 273         } else {
 274                 u32 inspos;
 275                 struct sub_seq *freesseq;
 276
 277                 /* Find where lower end should be inserted */
 278
 279                 inspos = nameseq_locate_subseq(nseq, lower);
 280
 281                 /* Fail if upper end overlaps into an existing entry */
 282
 283                 if ((inspos < nseq->first_free) &&
 284                     (upper >= nseq->sseqs[inspos].lower)) {
 285                         warn("Cannot publish {%u,%u,%u}, overlap error\n",
 286                              type, lower, upper);
 287                         return NULL;
 288                 }
 289
 290                 /* Ensure there is space for new sub-sequence */
 291
 292                 if (nseq->first_free == nseq->alloc) {
 293                         struct sub_seq *sseqs = tipc_subseq_alloc(nseq->alloc * 2);
 294
 295                         if (!sseqs) {
 296                                 warn("Cannot publish {%u,%u,%u}, no memory\n",
 297                                      type, lower, upper);
 298                                 return NULL;
 299                         }
 300                         memcpy(sseqs, nseq->sseqs,
 301                                nseq->alloc * sizeof(struct sub_seq));
 302                         kfree(nseq->sseqs);
 303                         nseq->sseqs = sseqs;
 304                         nseq->alloc *= 2;
 305                 }
 306
 307                 info = kzalloc(sizeof(*info), GFP_ATOMIC);
 308                 if (!info) {
 309                         warn("Cannot publish {%u,%u,%u}, no memory\n",
 310                              type, lower, upper);
 311                         return NULL;
 312                 }
 313
 314                 INIT_LIST_HEAD(&info->node_list);
 315                 INIT_LIST_HEAD(&info->cluster_list);
 316                 INIT_LIST_HEAD(&info->zone_list);
 317
 318                 /* Insert new sub-sequence */
 319
 320                 sseq = &nseq->sseqs[inspos];
 321                 freesseq = &nseq->sseqs[nseq->first_free];
 322                 memmove(sseq + 1, sseq, (freesseq - sseq) * sizeof(*sseq));
 323                 memset(sseq, 0, sizeof(*sseq));
 324                 nseq->first_free++;
 325                 sseq->lower = lower;
 326                 sseq->upper = upper;
 327                 sseq->info = info;
 328                 created_subseq = 1;
 329         }
 330
 331         /* Insert a publication: */
 332
 333         publ = publ_create(type, lower, upper, scope, node, port, key);
 334         if (!publ)
 335                 return NULL;
 336
 337         list_add(&publ->zone_list, &info->zone_list);
 338         info->zone_list_size++;
 339
 340         if (in_own_cluster(node)) {
 341                 list_add(&publ->cluster_list, &info->cluster_list);
 342                 info->cluster_list_size++;
 343         }
 344
 345         if (node == tipc_own_addr) {
 346                 list_add(&publ->node_list, &info->node_list);
 347                 info->node_list_size++;
 348         }
 349
 350         /*
 351          * Any subscriptions waiting for notification?
 352          */
 353         list_for_each_entry_safe(s, st, &nseq->subscriptions, nameseq_list) {
 354                 tipc_subscr_report_overlap(s,
 355                                            publ->lower,
 356                                            publ->upper,
 357                                            TIPC_PUBLISHED,
 358                                            publ->ref,
 359                                            publ->node,
 360                                            created_subseq);
 361         }
 362         return publ;
 363 }
 364
 365 /**
 366  * tipc_nameseq_remove_publ -
 367  *
 368  * NOTE: There may be cases where TIPC is asked to remove a publication
 369  * that is not in the name table.  For example, if another node issues a
 370  * publication for a name sequence that overlaps an existing name sequence
 371  * the publication will not be recorded, which means the publication won't
 372  * be found when the name sequence is later withdrawn by that node.
 373  * A failed withdraw request simply returns a failure indication and lets the
 374  * caller issue any error or warning messages associated with such a problem.
 375  */
 376
 377 static struct publication *tipc_nameseq_remove_publ(struct name_seq *nseq, u32 inst,
 378                                                     u32 node, u32 ref, u32 key)
 379 {
 380         struct publication *publ;
 381         struct sub_seq *sseq = nameseq_find_subseq(nseq, inst);
 382         struct name_info *info;
 383         struct sub_seq *free;
 384         struct tipc_subscription *s, *st;
 385         int removed_subseq = 0;
 386
 387         if (!sseq)
 388                 return NULL;
 389
 390         info = sseq->info;
 391
 392         /* Locate publication, if it exists */
 393
 394         list_for_each_entry(publ, &info->zone_list, zone_list) {
 395                 if ((publ->key == key) && (publ->ref == ref) &&
 396                     (!publ->node || (publ->node == node)))
 397                         goto found;
 398         }
 399         return NULL;
 400
 401 found:
 402         /* Remove publication from zone scope list */
 403
 404         list_del(&publ->zone_list);
 405         info->zone_list_size--;
 406
 407         /* Remove publication from cluster scope list, if present */
 408
 409         if (in_own_cluster(node)) {
 410                 list_del(&publ->cluster_list);
 411                 info->cluster_list_size--;
 412         }
 413
 414         /* Remove publication from node scope list, if present */
 415
 416         if (node == tipc_own_addr) {
 417                 list_del(&publ->node_list);
 418                 info->node_list_size--;
 419         }
 420
 421         /* Contract subseq list if no more publications for that subseq */
 422
 423         if (list_empty(&info->zone_list)) {
 424                 kfree(info);
 425                 free = &nseq->sseqs[nseq->first_free--];
 426                 memmove(sseq, sseq + 1, (free - (sseq + 1)) * sizeof(*sseq));
 427                 removed_subseq = 1;
 428         }
 429
 430         /* Notify any waiting subscriptions */
 431
 432         list_for_each_entry_safe(s, st, &nseq->subscriptions, nameseq_list) {
 433                 tipc_subscr_report_overlap(s,
 434                                            publ->lower,
 435                                            publ->upper,
 436                                            TIPC_WITHDRAWN,
 437                                            publ->ref,
 438                                            publ->node,
 439                                            removed_subseq);
 440         }
 441
 442         return publ;
 443 }
 444
 445 /**
 446  * tipc_nameseq_subscribe: attach a subscription, and issue
 447  * the prescribed number of events if there is any sub-
 448  * sequence overlapping with the requested sequence
 449  */
 450
 451 static void tipc_nameseq_subscribe(struct name_seq *nseq,
 452                                         struct tipc_subscription *s)
 453 {
 454         struct sub_seq *sseq = nseq->sseqs;
 455
 456         list_add(&s->nameseq_list, &nseq->subscriptions);
 457
 458         if (!sseq)
 459                 return;
 460
 461         while (sseq != &nseq->sseqs[nseq->first_free]) {
 462                 if (tipc_subscr_overlap(s, sseq->lower, sseq->upper)) {
 463                         struct publication *crs;
 464                         struct name_info *info = sseq->info;
 465                         int must_report = 1;
 466
 467                         list_for_each_entry(crs, &info->zone_list, zone_list) {
 468                                 tipc_subscr_report_overlap(s,
 469                                                            sseq->lower,
 470                                                            sseq->upper,
 471                                                            TIPC_PUBLISHED,
 472                                                            crs->ref,
 473                                                            crs->node,
 474                                                            must_report);
 475                                 must_report = 0;
 476                         }
 477                 }
 478                 sseq++;
 479         }
 480 }
 481
 482 static struct name_seq *nametbl_find_seq(u32 type)
 483 {
 484         struct hlist_head *seq_head;
 485         struct hlist_node *seq_node;
 486         struct name_seq *ns;
 487
 488         seq_head = &table.types[hash(type)];
 489         hlist_for_each_entry(ns, seq_node, seq_head, ns_list) {
 490                 if (ns->type == type)
 491                         return ns;
 492         }
 493
 494         return NULL;
 495 };
 496
 497 struct publication *tipc_nametbl_insert_publ(u32 type, u32 lower, u32 upper,
 498                                              u32 scope, u32 node, u32 port, u32 key)
 499 {
 500         struct name_seq *seq = nametbl_find_seq(type);
 501
 502         if (lower > upper) {
 503                 warn("Failed to publish illegal {%u,%u,%u}\n",
 504                      type, lower, upper);
 505                 return NULL;
 506         }
 507
 508         if (!seq)
 509                 seq = tipc_nameseq_create(type, &table.types[hash(type)]);
 510         if (!seq)
 511                 return NULL;
 512
 513         return tipc_nameseq_insert_publ(seq, type, lower, upper,
 514                                         scope, node, port, key);
 515 }
 516
 517 struct publication *tipc_nametbl_remove_publ(u32 type, u32 lower,
 518                                              u32 node, u32 ref, u32 key)
 519 {
 520         struct publication *publ;
 521         struct name_seq *seq = nametbl_find_seq(type);
 522
 523         if (!seq)
 524                 return NULL;
 525
 526         publ = tipc_nameseq_remove_publ(seq, lower, node, ref, key);
 527
 528         if (!seq->first_free && list_empty(&seq->subscriptions)) {
 529                 hlist_del_init(&seq->ns_list);
 530                 kfree(seq->sseqs);
 531                 kfree(seq);
 532         }
 533         return publ;
 534 }
 535
 536 /*
 537  * tipc_nametbl_translate - translate name to port id
 538  *
 539  * Note: on entry 'destnode' is the search domain used during translation;
 540  *       on exit it passes back the node address of the matching port (if any)
 541  */
 542
 543 u32 tipc_nametbl_translate(u32 type, u32 instance, u32 *destnode)
 544 {
 545         struct sub_seq *sseq;
 546         struct name_info *info;
 547         struct publication *publ;
 548         struct name_seq *seq;
 549         u32 ref = 0;
 550
 551         if (!tipc_in_scope(*destnode, tipc_own_addr))
 552                 return 0;
 553
 554         read_lock_bh(&tipc_nametbl_lock);
 555         seq = nametbl_find_seq(type);
 556         if (unlikely(!seq))
 557                 goto not_found;
 558         sseq = nameseq_find_subseq(seq, instance);
 559         if (unlikely(!sseq))
 560                 goto not_found;
 561         spin_lock_bh(&seq->lock);
 562         info = sseq->info;
 563
 564         /* Closest-First Algorithm: */
 565         if (likely(!*destnode)) {
 566                 if (!list_empty(&info->node_list)) {
 567                         publ = list_first_entry(&info->node_list,
 568                                                 struct publication,
 569                                                 node_list);
 570                         list_move_tail(&publ->node_list,
 571                                        &info->node_list);
 572                 } else if (!list_empty(&info->cluster_list)) {
 573                         publ = list_first_entry(&info->cluster_list,
 574                                                 struct publication,
 575                                                 cluster_list);
 576                         list_move_tail(&publ->cluster_list,
 577                                        &info->cluster_list);
 578                 } else {
 579                         publ = list_first_entry(&info->zone_list,
 580                                                 struct publication,
 581                                                 zone_list);
 582                         list_move_tail(&publ->zone_list,
 583                                        &info->zone_list);
 584                 }
 585         }
 586
 587         /* Round-Robin Algorithm: */
 588         else if (*destnode == tipc_own_addr) {
 589                 if (list_empty(&info->node_list))
 590                         goto no_match;
 591                 publ = list_first_entry(&info->node_list, struct publication,
 592                                         node_list);
 593                 list_move_tail(&publ->node_list, &info->node_list);
 594         } else if (in_own_cluster(*destnode)) {
 595                 if (list_empty(&info->cluster_list))
 596                         goto no_match;
 597                 publ = list_first_entry(&info->cluster_list, struct publication,
 598                                         cluster_list);
 599                 list_move_tail(&publ->cluster_list, &info->cluster_list);
 600         } else {
 601                 publ = list_first_entry(&info->zone_list, struct publication,
 602                                         zone_list);
 603                 list_move_tail(&publ->zone_list, &info->zone_list);
 604         }
 605
 606         ref = publ->ref;
 607         *destnode = publ->node;
 608 no_match:
 609         spin_unlock_bh(&seq->lock);
 610 not_found:
 611         read_unlock_bh(&tipc_nametbl_lock);
 612         return ref;
 613 }
 614
 615 /**
 616  * tipc_nametbl_mc_translate - find multicast destinations
 617  *
 618  * Creates list of all local ports that overlap the given multicast address;
 619  * also determines if any off-node ports overlap.
 620  *
 621  * Note: Publications with a scope narrower than 'limit' are ignored.
 622  * (i.e. local node-scope publications mustn't receive messages arriving
 623  * from another node, even if the multcast link brought it here)
 624  *
 625  * Returns non-zero if any off-node ports overlap
 626  */
 627
 628 int tipc_nametbl_mc_translate(u32 type, u32 lower, u32 upper, u32 limit,
 629                               struct tipc_port_list *dports)
 630 {
 631         struct name_seq *seq;
 632         struct sub_seq *sseq;
 633         struct sub_seq *sseq_stop;
 634         struct name_info *info;
 635         int res = 0;
 636
 637         read_lock_bh(&tipc_nametbl_lock);
 638         seq = nametbl_find_seq(type);
 639         if (!seq)
 640                 goto exit;
 641
 642         spin_lock_bh(&seq->lock);
 643
 644         sseq = seq->sseqs + nameseq_locate_subseq(seq, lower);
 645         sseq_stop = seq->sseqs + seq->first_free;
 646         for (; sseq != sseq_stop; sseq++) {
 647                 struct publication *publ;
 648
 649                 if (sseq->lower > upper)
 650                         break;
 651
 652                 info = sseq->info;
 653                 list_for_each_entry(publ, &info->node_list, node_list) {
 654                         if (publ->scope <= limit)
 655                                 tipc_port_list_add(dports, publ->ref);
 656                 }
 657
 658                 if (info->cluster_list_size != info->node_list_size)
 659                         res = 1;
 660         }
 661
 662         spin_unlock_bh(&seq->lock);
 663 exit:
 664         read_unlock_bh(&tipc_nametbl_lock);
 665         return res;
 666 }
 667
 668 /**
 669  * tipc_nametbl_publish_rsv - publish port name using a reserved name type
 670  */
 671
 672 int tipc_nametbl_publish_rsv(u32 ref, unsigned int scope,
 673                         struct tipc_name_seq const *seq)
 674 {
 675         int res;
 676
 677         atomic_inc(&rsv_publ_ok);
 678         res = tipc_publish(ref, scope, seq);
 679         atomic_dec(&rsv_publ_ok);
 680         return res;
 681 }
 682
 683 /**
 684  * tipc_nametbl_publish - add name publication to network name tables
 685  */
 686
 687 struct publication *tipc_nametbl_publish(u32 type, u32 lower, u32 upper,
 688                                     u32 scope, u32 port_ref, u32 key)
 689 {
 690         struct publication *publ;
 691
 692         if (table.local_publ_count >= tipc_max_publications) {
 693                 warn("Publication failed, local publication limit reached (%u)\n",
 694                      tipc_max_publications);
 695                 return NULL;
 696         }
 697         if ((type < TIPC_RESERVED_TYPES) && !atomic_read(&rsv_publ_ok)) {
 698                 warn("Publication failed, reserved name {%u,%u,%u}\n",
 699                      type, lower, upper);
 700                 return NULL;
 701         }
 702
 703         write_lock_bh(&tipc_nametbl_lock);
 704         table.local_publ_count++;
 705         publ = tipc_nametbl_insert_publ(type, lower, upper, scope,
 706                                    tipc_own_addr, port_ref, key);
 707         if (publ && (scope != TIPC_NODE_SCOPE))
 708                 tipc_named_publish(publ);
 709         write_unlock_bh(&tipc_nametbl_lock);
 710         return publ;
 711 }
 712
 713 /**
 714  * tipc_nametbl_withdraw - withdraw name publication from network name tables
 715  */
 716
 717 int tipc_nametbl_withdraw(u32 type, u32 lower, u32 ref, u32 key)
 718 {
 719         struct publication *publ;
 720
 721         write_lock_bh(&tipc_nametbl_lock);
 722         publ = tipc_nametbl_remove_publ(type, lower, tipc_own_addr, ref, key);
 723         if (likely(publ)) {
 724                 table.local_publ_count--;
 725                 if (publ->scope != TIPC_NODE_SCOPE)
 726                         tipc_named_withdraw(publ);
 727                 write_unlock_bh(&tipc_nametbl_lock);
 728                 list_del_init(&publ->pport_list);
 729                 kfree(publ);
 730                 return 1;
 731         }
 732         write_unlock_bh(&tipc_nametbl_lock);
 733         err("Unable to remove local publication\n"
 734             "(type=%u, lower=%u, ref=%u, key=%u)\n",
 735             type, lower, ref, key);
 736         return 0;
 737 }
 738
 739 /**
 740  * tipc_nametbl_subscribe - add a subscription object to the name table
 741  */
 742
 743 void tipc_nametbl_subscribe(struct tipc_subscription *s)
 744 {
 745         u32 type = s->seq.type;
 746         struct name_seq *seq;
 747
 748         write_lock_bh(&tipc_nametbl_lock);
 749         seq = nametbl_find_seq(type);
 750         if (!seq)
 751                 seq = tipc_nameseq_create(type, &table.types[hash(type)]);
 752         if (seq) {
 753                 spin_lock_bh(&seq->lock);
 754                 tipc_nameseq_subscribe(seq, s);
 755                 spin_unlock_bh(&seq->lock);
 756         } else {
 757                 warn("Failed to create subscription for {%u,%u,%u}\n",
 758                      s->seq.type, s->seq.lower, s->seq.upper);
 759         }
 760         write_unlock_bh(&tipc_nametbl_lock);
 761 }
 762
 763 /**
 764  * tipc_nametbl_unsubscribe - remove a subscription object from name table
 765  */
 766
 767 void tipc_nametbl_unsubscribe(struct tipc_subscription *s)
 768 {
 769         struct name_seq *seq;
 770
 771         write_lock_bh(&tipc_nametbl_lock);
 772         seq = nametbl_find_seq(s->seq.type);
 773         if (seq != NULL) {
 774                 spin_lock_bh(&seq->lock);
 775                 list_del_init(&s->nameseq_list);
 776                 spin_unlock_bh(&seq->lock);
 777                 if ((seq->first_free == 0) && list_empty(&seq->subscriptions)) {
 778                         hlist_del_init(&seq->ns_list);
 779                         kfree(seq->sseqs);
 780                         kfree(seq);
 781                 }
 782         }
 783         write_unlock_bh(&tipc_nametbl_lock);
 784 }
 785
 786
 787 /**
 788  * subseq_list: print specified sub-sequence contents into the given buffer
 789  */
 790
 791 static void subseq_list(struct sub_seq *sseq, struct print_buf *buf, u32 depth,
 792                         u32 index)
 793 {
 794         char portIdStr[27];
 795         const char *scope_str[] = {"", " zone", " cluster", " node"};
 796         struct publication *publ;
 797         struct name_info *info;
 798
 799         tipc_printf(buf, "%-10u %-10u ", sseq->lower, sseq->upper);
 800
 801         if (depth == 2) {
 802                 tipc_printf(buf, "\n");
 803                 return;
 804         }
 805
 806         info = sseq->info;
 807
 808         list_for_each_entry(publ, &info->zone_list, zone_list) {
 809                 sprintf(portIdStr, "<%u.%u.%u:%u>",
 810                          tipc_zone(publ->node), tipc_cluster(publ->node),
 811                          tipc_node(publ->node), publ->ref);
 812                 tipc_printf(buf, "%-26s ", portIdStr);
 813                 if (depth > 3) {
 814                         tipc_printf(buf, "%-10u %s", publ->key,
 815                                     scope_str[publ->scope]);
 816                 }
 817                 if (!list_is_last(&publ->zone_list, &info->zone_list))
 818                         tipc_printf(buf, "\n%33s", " ");
 819         };
 820
 821         tipc_printf(buf, "\n");
 822 }
 823
 824 /**
 825  * nameseq_list: print specified name sequence contents into the given buffer
 826  */
 827
 828 static void nameseq_list(struct name_seq *seq, struct print_buf *buf, u32 depth,
 829                          u32 type, u32 lowbound, u32 upbound, u32 index)
 830 {
 831         struct sub_seq *sseq;
 832         char typearea[11];
 833
 834         if (seq->first_free == 0)
 835                 return;
 836
 837         sprintf(typearea, "%-10u", seq->type);
 838
 839         if (depth == 1) {
 840                 tipc_printf(buf, "%s\n", typearea);
 841                 return;
 842         }
 843
 844         for (sseq = seq->sseqs; sseq != &seq->sseqs[seq->first_free]; sseq++) {
 845                 if ((lowbound <= sseq->upper) && (upbound >= sseq->lower)) {
 846                         tipc_printf(buf, "%s ", typearea);
 847                         spin_lock_bh(&seq->lock);
 848                         subseq_list(sseq, buf, depth, index);
 849                         spin_unlock_bh(&seq->lock);
 850                         sprintf(typearea, "%10s", " ");
 851                 }
 852         }
 853 }
 854
 855 /**
 856  * nametbl_header - print name table header into the given buffer
 857  */
 858
 859 static void nametbl_header(struct print_buf *buf, u32 depth)
 860 {
 861         const char *header[] = {
 862                 "Type       ",
 863                 "Lower      Upper      ",
 864                 "Port Identity              ",
 865                 "Publication Scope"
 866         };
 867
 868         int i;
 869
 870         if (depth > 4)
 871                 depth = 4;
 872         for (i = 0; i < depth; i++)
 873                 tipc_printf(buf, header[i]);
 874         tipc_printf(buf, "\n");
 875 }
 876
 877 /**
 878  * nametbl_list - print specified name table contents into the given buffer
 879  */
 880
 881 static void nametbl_list(struct print_buf *buf, u32 depth_info,
 882                          u32 type, u32 lowbound, u32 upbound)
 883 {
 884         struct hlist_head *seq_head;
 885         struct hlist_node *seq_node;
 886         struct name_seq *seq;
 887         int all_types;
 888         u32 depth;
 889         u32 i;
 890
 891         all_types = (depth_info & TIPC_NTQ_ALLTYPES);
 892         depth = (depth_info & ~TIPC_NTQ_ALLTYPES);
 893
 894         if (depth == 0)
 895                 return;
 896
 897         if (all_types) {
 898                 /* display all entries in name table to specified depth */
 899                 nametbl_header(buf, depth);
 900                 lowbound = 0;
 901                 upbound = ~0;
 902                 for (i = 0; i < tipc_nametbl_size; i++) {
 903                         seq_head = &table.types[i];
 904                         hlist_for_each_entry(seq, seq_node, seq_head, ns_list) {
 905                                 nameseq_list(seq, buf, depth, seq->type,
 906                                              lowbound, upbound, i);
 907                         }
 908                 }
 909         } else {
 910                 /* display only the sequence that matches the specified type */
 911                 if (upbound < lowbound) {
 912                         tipc_printf(buf, "invalid name sequence specified\n");
 913                         return;
 914                 }
 915                 nametbl_header(buf, depth);
 916                 i = hash(type);
 917                 seq_head = &table.types[i];
 918                 hlist_for_each_entry(seq, seq_node, seq_head, ns_list) {
 919                         if (seq->type == type) {
 920                                 nameseq_list(seq, buf, depth, type,
 921                                              lowbound, upbound, i);
 922                                 break;
 923                         }
 924                 }
 925         }
 926 }
 927
 928 #define MAX_NAME_TBL_QUERY 32768
 929
 930 struct sk_buff *tipc_nametbl_get(const void *req_tlv_area, int req_tlv_space)
 931 {
 932         struct sk_buff *buf;
 933         struct tipc_name_table_query *argv;
 934         struct tlv_desc *rep_tlv;
 935         struct print_buf b;
 936         int str_len;
 937
 938         if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NAME_TBL_QUERY))
 939                 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
 940
 941         buf = tipc_cfg_reply_alloc(TLV_SPACE(MAX_NAME_TBL_QUERY));
 942         if (!buf)
 943                 return NULL;
 944
 945         rep_tlv = (struct tlv_desc *)buf->data;
 946         tipc_printbuf_init(&b, TLV_DATA(rep_tlv), MAX_NAME_TBL_QUERY);
 947         argv = (struct tipc_name_table_query *)TLV_DATA(req_tlv_area);
 948         read_lock_bh(&tipc_nametbl_lock);
 949         nametbl_list(&b, ntohl(argv->depth), ntohl(argv->type),
 950                      ntohl(argv->lowbound), ntohl(argv->upbound));
 951         read_unlock_bh(&tipc_nametbl_lock);
 952         str_len = tipc_printbuf_validate(&b);
 953
 954         skb_put(buf, TLV_SPACE(str_len));
 955         TLV_SET(rep_tlv, TIPC_TLV_ULTRA_STRING, NULL, str_len);
 956
 957         return buf;
 958 }
 959
 960 int tipc_nametbl_init(void)
 961 {
 962         table.types = kcalloc(tipc_nametbl_size, sizeof(struct hlist_head),
 963                               GFP_ATOMIC);
 964         if (!table.types)
 965                 return -ENOMEM;
 966
 967         table.local_publ_count = 0;
 968         return 0;
 969 }
 970
 971 void tipc_nametbl_stop(void)
 972 {
 973         u32 i;
 974
 975         if (!table.types)
 976                 return;
 977
 978         /* Verify name table is empty, then release it */
 979
 980         write_lock_bh(&tipc_nametbl_lock);
 981         for (i = 0; i < tipc_nametbl_size; i++) {
 982                 if (!hlist_empty(&table.types[i]))
 983                         err("tipc_nametbl_stop(): hash chain %u is non-null\n", i);
 984         }
 985         kfree(table.types);
 986         table.types = NULL;
 987         write_unlock_bh(&tipc_nametbl_lock);
 988 }
 989