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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
44 #define 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 struct 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  */
74 struct 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  */
91 struct 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  */
107 struct name_table {
108         struct hlist_head *types;
109         u32 local_publ_count;
110 };
111
112 static struct name_table table;
113 DEFINE_RWLOCK(tipc_nametbl_lock);
114
115 static int hash(int x)
116 {
117         return x & (TIPC_NAMETBL_SIZE - 1);
118 }
119
120 /**
121  * publ_create - create a publication structure
122  */
123 static 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  */
149 static 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  */
160 static 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  */
185 static 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  */
199 static 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  */
228 static 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  */
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                 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  */
375 static 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
398 found:
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  */
442 static 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
473 static struct name_seq *nametbl_find_seq(u32 type)
474 {
475         struct hlist_head *seq_head;
476         struct name_seq *ns;
477
478         seq_head = &table.types[hash(type)];
479         hlist_for_each_entry(ns, seq_head, ns_list) {
480                 if (ns->type == type)
481                         return ns;
482         }
483
484         return NULL;
485 };
486
487 struct publication *tipc_nametbl_insert_publ(u32 type, u32 lower, u32 upper,
488                                              u32 scope, u32 node, u32 port, u32 key)
489 {
490         struct name_seq *seq = nametbl_find_seq(type);
491
492         if ((scope < TIPC_ZONE_SCOPE) || (scope > TIPC_NODE_SCOPE) ||
493             (lower > upper)) {
494                 pr_debug("Failed to publish illegal {%u,%u,%u} with scope %u\n",
495                          type, lower, upper, scope);
496                 return NULL;
497         }
498
499         if (!seq)
500                 seq = tipc_nameseq_create(type, &table.types[hash(type)]);
501         if (!seq)
502                 return NULL;
503
504         return tipc_nameseq_insert_publ(seq, type, lower, upper,
505                                         scope, node, port, key);
506 }
507
508 struct publication *tipc_nametbl_remove_publ(u32 type, u32 lower,
509                                              u32 node, u32 ref, u32 key)
510 {
511         struct publication *publ;
512         struct name_seq *seq = nametbl_find_seq(type);
513
514         if (!seq)
515                 return NULL;
516
517         publ = tipc_nameseq_remove_publ(seq, lower, node, ref, key);
518         nameseq_delete_empty(seq);
519         return publ;
520 }
521
522 /**
523  * tipc_nametbl_translate - perform name translation
524  *
525  * On entry, 'destnode' is the search domain used during translation.
526  *
527  * On exit:
528  * - if name translation is deferred to another node/cluster/zone,
529  *   leaves 'destnode' unchanged (will be non-zero) and returns 0
530  * - if name translation is attempted and succeeds, sets 'destnode'
531  *   to publishing node and returns port reference (will be non-zero)
532  * - if name translation is attempted and fails, sets 'destnode' to 0
533  *   and returns 0
534  */
535 u32 tipc_nametbl_translate(u32 type, u32 instance, u32 *destnode)
536 {
537         struct sub_seq *sseq;
538         struct name_info *info;
539         struct publication *publ;
540         struct name_seq *seq;
541         u32 ref = 0;
542         u32 node = 0;
543
544         if (!tipc_in_scope(*destnode, tipc_own_addr))
545                 return 0;
546
547         read_lock_bh(&tipc_nametbl_lock);
548         seq = nametbl_find_seq(type);
549         if (unlikely(!seq))
550                 goto not_found;
551         sseq = nameseq_find_subseq(seq, instance);
552         if (unlikely(!sseq))
553                 goto not_found;
554         spin_lock_bh(&seq->lock);
555         info = sseq->info;
556
557         /* Closest-First Algorithm */
558         if (likely(!*destnode)) {
559                 if (!list_empty(&info->node_list)) {
560                         publ = list_first_entry(&info->node_list,
561                                                 struct publication,
562                                                 node_list);
563                         list_move_tail(&publ->node_list,
564                                        &info->node_list);
565                 } else if (!list_empty(&info->cluster_list)) {
566                         publ = list_first_entry(&info->cluster_list,
567                                                 struct publication,
568                                                 cluster_list);
569                         list_move_tail(&publ->cluster_list,
570                                        &info->cluster_list);
571                 } else {
572                         publ = list_first_entry(&info->zone_list,
573                                                 struct publication,
574                                                 zone_list);
575                         list_move_tail(&publ->zone_list,
576                                        &info->zone_list);
577                 }
578         }
579
580         /* Round-Robin Algorithm */
581         else if (*destnode == tipc_own_addr) {
582                 if (list_empty(&info->node_list))
583                         goto no_match;
584                 publ = list_first_entry(&info->node_list, struct publication,
585                                         node_list);
586                 list_move_tail(&publ->node_list, &info->node_list);
587         } else if (in_own_cluster_exact(*destnode)) {
588                 if (list_empty(&info->cluster_list))
589                         goto no_match;
590                 publ = list_first_entry(&info->cluster_list, struct publication,
591                                         cluster_list);
592                 list_move_tail(&publ->cluster_list, &info->cluster_list);
593         } else {
594                 publ = list_first_entry(&info->zone_list, struct publication,
595                                         zone_list);
596                 list_move_tail(&publ->zone_list, &info->zone_list);
597         }
598
599         ref = publ->ref;
600         node = publ->node;
601 no_match:
602         spin_unlock_bh(&seq->lock);
603 not_found:
604         read_unlock_bh(&tipc_nametbl_lock);
605         *destnode = node;
606         return ref;
607 }
608
609 /**
610  * tipc_nametbl_mc_translate - find multicast destinations
611  *
612  * Creates list of all local ports that overlap the given multicast address;
613  * also determines if any off-node ports overlap.
614  *
615  * Note: Publications with a scope narrower than 'limit' are ignored.
616  * (i.e. local node-scope publications mustn't receive messages arriving
617  * from another node, even if the multcast link brought it here)
618  *
619  * Returns non-zero if any off-node ports overlap
620  */
621 int tipc_nametbl_mc_translate(u32 type, u32 lower, u32 upper, u32 limit,
622                               struct tipc_port_list *dports)
623 {
624         struct name_seq *seq;
625         struct sub_seq *sseq;
626         struct sub_seq *sseq_stop;
627         struct name_info *info;
628         int res = 0;
629
630         read_lock_bh(&tipc_nametbl_lock);
631         seq = nametbl_find_seq(type);
632         if (!seq)
633                 goto exit;
634
635         spin_lock_bh(&seq->lock);
636
637         sseq = seq->sseqs + nameseq_locate_subseq(seq, lower);
638         sseq_stop = seq->sseqs + seq->first_free;
639         for (; sseq != sseq_stop; sseq++) {
640                 struct publication *publ;
641
642                 if (sseq->lower > upper)
643                         break;
644
645                 info = sseq->info;
646                 list_for_each_entry(publ, &info->node_list, node_list) {
647                         if (publ->scope <= limit)
648                                 tipc_port_list_add(dports, publ->ref);
649                 }
650
651                 if (info->cluster_list_size != info->node_list_size)
652                         res = 1;
653         }
654
655         spin_unlock_bh(&seq->lock);
656 exit:
657         read_unlock_bh(&tipc_nametbl_lock);
658         return res;
659 }
660
661 /*
662  * tipc_nametbl_publish - add name publication to network name tables
663  */
664 struct publication *tipc_nametbl_publish(u32 type, u32 lower, u32 upper,
665                                          u32 scope, u32 port_ref, u32 key)
666 {
667         struct publication *publ;
668
669         if (table.local_publ_count >= TIPC_MAX_PUBLICATIONS) {
670                 pr_warn("Publication failed, local publication limit reached (%u)\n",
671                         TIPC_MAX_PUBLICATIONS);
672                 return NULL;
673         }
674
675         write_lock_bh(&tipc_nametbl_lock);
676         publ = tipc_nametbl_insert_publ(type, lower, upper, scope,
677                                    tipc_own_addr, port_ref, key);
678         if (likely(publ)) {
679                 table.local_publ_count++;
680                 tipc_named_publish(publ);
681         }
682         write_unlock_bh(&tipc_nametbl_lock);
683         return publ;
684 }
685
686 /**
687  * tipc_nametbl_withdraw - withdraw name publication from network name tables
688  */
689 int tipc_nametbl_withdraw(u32 type, u32 lower, u32 ref, u32 key)
690 {
691         struct publication *publ;
692
693         write_lock_bh(&tipc_nametbl_lock);
694         publ = tipc_nametbl_remove_publ(type, lower, tipc_own_addr, ref, key);
695         if (likely(publ)) {
696                 table.local_publ_count--;
697                 tipc_named_withdraw(publ);
698                 write_unlock_bh(&tipc_nametbl_lock);
699                 list_del_init(&publ->pport_list);
700                 kfree(publ);
701                 return 1;
702         }
703         write_unlock_bh(&tipc_nametbl_lock);
704         pr_err("Unable to remove local publication\n"
705                "(type=%u, lower=%u, ref=%u, key=%u)\n",
706                type, lower, ref, key);
707         return 0;
708 }
709
710 /**
711  * tipc_nametbl_subscribe - add a subscription object to the name table
712  */
713 void tipc_nametbl_subscribe(struct tipc_subscription *s)
714 {
715         u32 type = s->seq.type;
716         struct name_seq *seq;
717
718         write_lock_bh(&tipc_nametbl_lock);
719         seq = nametbl_find_seq(type);
720         if (!seq)
721                 seq = tipc_nameseq_create(type, &table.types[hash(type)]);
722         if (seq) {
723                 spin_lock_bh(&seq->lock);
724                 tipc_nameseq_subscribe(seq, s);
725                 spin_unlock_bh(&seq->lock);
726         } else {
727                 pr_warn("Failed to create subscription for {%u,%u,%u}\n",
728                         s->seq.type, s->seq.lower, s->seq.upper);
729         }
730         write_unlock_bh(&tipc_nametbl_lock);
731 }
732
733 /**
734  * tipc_nametbl_unsubscribe - remove a subscription object from name table
735  */
736 void tipc_nametbl_unsubscribe(struct tipc_subscription *s)
737 {
738         struct name_seq *seq;
739
740         write_lock_bh(&tipc_nametbl_lock);
741         seq = nametbl_find_seq(s->seq.type);
742         if (seq != NULL) {
743                 spin_lock_bh(&seq->lock);
744                 list_del_init(&s->nameseq_list);
745                 spin_unlock_bh(&seq->lock);
746                 nameseq_delete_empty(seq);
747         }
748         write_unlock_bh(&tipc_nametbl_lock);
749 }
750
751
752 /**
753  * subseq_list - print specified sub-sequence contents into the given buffer
754  */
755 static int subseq_list(struct sub_seq *sseq, char *buf, int len, u32 depth,
756                        u32 index)
757 {
758         char portIdStr[27];
759         const char *scope_str[] = {"", " zone", " cluster", " node"};
760         struct publication *publ;
761         struct name_info *info;
762         int ret;
763
764         ret = tipc_snprintf(buf, len, "%-10u %-10u ", sseq->lower, sseq->upper);
765
766         if (depth == 2) {
767                 ret += tipc_snprintf(buf - ret, len + ret, "\n");
768                 return ret;
769         }
770
771         info = sseq->info;
772
773         list_for_each_entry(publ, &info->zone_list, zone_list) {
774                 sprintf(portIdStr, "<%u.%u.%u:%u>",
775                          tipc_zone(publ->node), tipc_cluster(publ->node),
776                          tipc_node(publ->node), publ->ref);
777                 ret += tipc_snprintf(buf + ret, len - ret, "%-26s ", portIdStr);
778                 if (depth > 3) {
779                         ret += tipc_snprintf(buf + ret, len - ret, "%-10u %s",
780                                              publ->key, scope_str[publ->scope]);
781                 }
782                 if (!list_is_last(&publ->zone_list, &info->zone_list))
783                         ret += tipc_snprintf(buf + ret, len - ret,
784                                              "\n%33s", " ");
785         }
786
787         ret += tipc_snprintf(buf + ret, len - ret, "\n");
788         return ret;
789 }
790
791 /**
792  * nameseq_list - print specified name sequence contents into the given buffer
793  */
794 static int nameseq_list(struct name_seq *seq, char *buf, int len, u32 depth,
795                         u32 type, u32 lowbound, u32 upbound, u32 index)
796 {
797         struct sub_seq *sseq;
798         char typearea[11];
799         int ret = 0;
800
801         if (seq->first_free == 0)
802                 return 0;
803
804         sprintf(typearea, "%-10u", seq->type);
805
806         if (depth == 1) {
807                 ret += tipc_snprintf(buf, len, "%s\n", typearea);
808                 return ret;
809         }
810
811         for (sseq = seq->sseqs; sseq != &seq->sseqs[seq->first_free]; sseq++) {
812                 if ((lowbound <= sseq->upper) && (upbound >= sseq->lower)) {
813                         ret += tipc_snprintf(buf + ret, len - ret, "%s ",
814                                             typearea);
815                         spin_lock_bh(&seq->lock);
816                         ret += subseq_list(sseq, buf + ret, len - ret,
817                                           depth, index);
818                         spin_unlock_bh(&seq->lock);
819                         sprintf(typearea, "%10s", " ");
820                 }
821         }
822         return ret;
823 }
824
825 /**
826  * nametbl_header - print name table header into the given buffer
827  */
828 static int nametbl_header(char *buf, int len, u32 depth)
829 {
830         const char *header[] = {
831                 "Type       ",
832                 "Lower      Upper      ",
833                 "Port Identity              ",
834                 "Publication Scope"
835         };
836
837         int i;
838         int ret = 0;
839
840         if (depth > 4)
841                 depth = 4;
842         for (i = 0; i < depth; i++)
843                 ret += tipc_snprintf(buf + ret, len - ret, header[i]);
844         ret += tipc_snprintf(buf + ret, len - ret, "\n");
845         return ret;
846 }
847
848 /**
849  * nametbl_list - print specified name table contents into the given buffer
850  */
851 static int nametbl_list(char *buf, int len, u32 depth_info,
852                         u32 type, u32 lowbound, u32 upbound)
853 {
854         struct hlist_head *seq_head;
855         struct name_seq *seq;
856         int all_types;
857         int ret = 0;
858         u32 depth;
859         u32 i;
860
861         all_types = (depth_info & TIPC_NTQ_ALLTYPES);
862         depth = (depth_info & ~TIPC_NTQ_ALLTYPES);
863
864         if (depth == 0)
865                 return 0;
866
867         if (all_types) {
868                 /* display all entries in name table to specified depth */
869                 ret += nametbl_header(buf, len, depth);
870                 lowbound = 0;
871                 upbound = ~0;
872                 for (i = 0; i < TIPC_NAMETBL_SIZE; i++) {
873                         seq_head = &table.types[i];
874                         hlist_for_each_entry(seq, seq_head, ns_list) {
875                                 ret += nameseq_list(seq, buf + ret, len - ret,
876                                                    depth, seq->type,
877                                                    lowbound, upbound, i);
878                         }
879                 }
880         } else {
881                 /* display only the sequence that matches the specified type */
882                 if (upbound < lowbound) {
883                         ret += tipc_snprintf(buf + ret, len - ret,
884                                         "invalid name sequence specified\n");
885                         return ret;
886                 }
887                 ret += nametbl_header(buf + ret, len - ret, depth);
888                 i = hash(type);
889                 seq_head = &table.types[i];
890                 hlist_for_each_entry(seq, seq_head, ns_list) {
891                         if (seq->type == type) {
892                                 ret += nameseq_list(seq, buf + ret, len - ret,
893                                                    depth, type,
894                                                    lowbound, upbound, i);
895                                 break;
896                         }
897                 }
898         }
899         return ret;
900 }
901
902 struct sk_buff *tipc_nametbl_get(const void *req_tlv_area, int req_tlv_space)
903 {
904         struct sk_buff *buf;
905         struct tipc_name_table_query *argv;
906         struct tlv_desc *rep_tlv;
907         char *pb;
908         int pb_len;
909         int str_len;
910
911         if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NAME_TBL_QUERY))
912                 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
913
914         buf = tipc_cfg_reply_alloc(TLV_SPACE(ULTRA_STRING_MAX_LEN));
915         if (!buf)
916                 return NULL;
917
918         rep_tlv = (struct tlv_desc *)buf->data;
919         pb = TLV_DATA(rep_tlv);
920         pb_len = ULTRA_STRING_MAX_LEN;
921         argv = (struct tipc_name_table_query *)TLV_DATA(req_tlv_area);
922         read_lock_bh(&tipc_nametbl_lock);
923         str_len = nametbl_list(pb, pb_len, ntohl(argv->depth),
924                                ntohl(argv->type),
925                                ntohl(argv->lowbound), ntohl(argv->upbound));
926         read_unlock_bh(&tipc_nametbl_lock);
927         str_len += 1;   /* for "\0" */
928         skb_put(buf, TLV_SPACE(str_len));
929         TLV_SET(rep_tlv, TIPC_TLV_ULTRA_STRING, NULL, str_len);
930
931         return buf;
932 }
933
934 int tipc_nametbl_init(void)
935 {
936         table.types = kcalloc(TIPC_NAMETBL_SIZE, sizeof(struct hlist_head),
937                               GFP_ATOMIC);
938         if (!table.types)
939                 return -ENOMEM;
940
941         table.local_publ_count = 0;
942         return 0;
943 }
944
945 void tipc_nametbl_stop(void)
946 {
947         u32 i;
948
949         if (!table.types)
950                 return;
951
952         /* Verify name table is empty, then release it */
953         write_lock_bh(&tipc_nametbl_lock);
954         for (i = 0; i < TIPC_NAMETBL_SIZE; i++) {
955                 if (hlist_empty(&table.types[i]))
956                         continue;
957                 pr_err("nametbl_stop(): orphaned hash chain detected\n");
958                 break;
959         }
960         kfree(table.types);
961         table.types = NULL;
962         write_unlock_bh(&tipc_nametbl_lock);
963 }