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