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[karo-tx-linux.git] / 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 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 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
488 struct 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
509 struct 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  */
536 u32 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;
602 no_match:
603         spin_unlock_bh(&seq->lock);
604 not_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  */
622 int 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);
657 exit:
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  */
665 struct 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  */
690 int 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  */
714 void 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  */
737 void 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  */
756 static 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  */
795 static 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  */
829 static 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  */
852 static 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
904 struct 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
936 int 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
947 void 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 }