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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         return kcalloc(cnt, sizeof(struct sub_seq), GFP_ATOMIC);
152 }
153
154 /**
155  * tipc_nameseq_create - create a name sequence structure for the specified 'type'
156  *
157  * Allocates a single sub-sequence structure and sets it to all 0's.
158  */
159 static struct name_seq *tipc_nameseq_create(u32 type, struct hlist_head *seq_head)
160 {
161         struct name_seq *nseq = kzalloc(sizeof(*nseq), GFP_ATOMIC);
162         struct sub_seq *sseq = tipc_subseq_alloc(1);
163
164         if (!nseq || !sseq) {
165                 pr_warn("Name sequence creation failed, no memory\n");
166                 kfree(nseq);
167                 kfree(sseq);
168                 return NULL;
169         }
170
171         spin_lock_init(&nseq->lock);
172         nseq->type = type;
173         nseq->sseqs = sseq;
174         nseq->alloc = 1;
175         INIT_HLIST_NODE(&nseq->ns_list);
176         INIT_LIST_HEAD(&nseq->subscriptions);
177         hlist_add_head(&nseq->ns_list, seq_head);
178         return nseq;
179 }
180
181 /*
182  * nameseq_delete_empty - deletes a name sequence structure if now unused
183  */
184 static void nameseq_delete_empty(struct name_seq *seq)
185 {
186         if (!seq->first_free && list_empty(&seq->subscriptions)) {
187                 hlist_del_init(&seq->ns_list);
188                 kfree(seq->sseqs);
189                 kfree(seq);
190         }
191 }
192
193 /**
194  * nameseq_find_subseq - find sub-sequence (if any) matching a name instance
195  *
196  * Very time-critical, so binary searches through sub-sequence array.
197  */
198 static struct sub_seq *nameseq_find_subseq(struct name_seq *nseq,
199                                            u32 instance)
200 {
201         struct sub_seq *sseqs = nseq->sseqs;
202         int low = 0;
203         int high = nseq->first_free - 1;
204         int mid;
205
206         while (low <= high) {
207                 mid = (low + high) / 2;
208                 if (instance < sseqs[mid].lower)
209                         high = mid - 1;
210                 else if (instance > sseqs[mid].upper)
211                         low = mid + 1;
212                 else
213                         return &sseqs[mid];
214         }
215         return NULL;
216 }
217
218 /**
219  * nameseq_locate_subseq - determine position of name instance in sub-sequence
220  *
221  * Returns index in sub-sequence array of the entry that contains the specified
222  * instance value; if no entry contains that value, returns the position
223  * where a new entry for it would be inserted in the array.
224  *
225  * Note: Similar to binary search code for locating a sub-sequence.
226  */
227 static u32 nameseq_locate_subseq(struct name_seq *nseq, u32 instance)
228 {
229         struct sub_seq *sseqs = nseq->sseqs;
230         int low = 0;
231         int high = nseq->first_free - 1;
232         int mid;
233
234         while (low <= high) {
235                 mid = (low + high) / 2;
236                 if (instance < sseqs[mid].lower)
237                         high = mid - 1;
238                 else if (instance > sseqs[mid].upper)
239                         low = mid + 1;
240                 else
241                         return mid;
242         }
243         return low;
244 }
245
246 /**
247  * tipc_nameseq_insert_publ
248  */
249 static struct publication *tipc_nameseq_insert_publ(struct name_seq *nseq,
250                                                     u32 type, u32 lower, u32 upper,
251                                                     u32 scope, u32 node, u32 port, u32 key)
252 {
253         struct tipc_subscription *s;
254         struct tipc_subscription *st;
255         struct publication *publ;
256         struct sub_seq *sseq;
257         struct name_info *info;
258         int created_subseq = 0;
259
260         sseq = nameseq_find_subseq(nseq, lower);
261         if (sseq) {
262
263                 /* Lower end overlaps existing entry => need an exact match */
264                 if ((sseq->lower != lower) || (sseq->upper != upper)) {
265                         pr_warn("Cannot publish {%u,%u,%u}, overlap error\n",
266                                 type, lower, upper);
267                         return NULL;
268                 }
269
270                 info = sseq->info;
271
272                 /* Check if an identical publication already exists */
273                 list_for_each_entry(publ, &info->zone_list, zone_list) {
274                         if ((publ->ref == port) && (publ->key == key) &&
275                             (!publ->node || (publ->node == node)))
276                                 return NULL;
277                 }
278         } else {
279                 u32 inspos;
280                 struct sub_seq *freesseq;
281
282                 /* Find where lower end should be inserted */
283                 inspos = nameseq_locate_subseq(nseq, lower);
284
285                 /* Fail if upper end overlaps into an existing entry */
286                 if ((inspos < nseq->first_free) &&
287                     (upper >= nseq->sseqs[inspos].lower)) {
288                         pr_warn("Cannot publish {%u,%u,%u}, overlap error\n",
289                                 type, lower, upper);
290                         return NULL;
291                 }
292
293                 /* Ensure there is space for new sub-sequence */
294                 if (nseq->first_free == nseq->alloc) {
295                         struct sub_seq *sseqs = tipc_subseq_alloc(nseq->alloc * 2);
296
297                         if (!sseqs) {
298                                 pr_warn("Cannot publish {%u,%u,%u}, no memory\n",
299                                         type, lower, upper);
300                                 return NULL;
301                         }
302                         memcpy(sseqs, nseq->sseqs,
303                                nseq->alloc * sizeof(struct sub_seq));
304                         kfree(nseq->sseqs);
305                         nseq->sseqs = sseqs;
306                         nseq->alloc *= 2;
307                 }
308
309                 info = kzalloc(sizeof(*info), GFP_ATOMIC);
310                 if (!info) {
311                         pr_warn("Cannot publish {%u,%u,%u}, no memory\n",
312                                 type, lower, upper);
313                         return NULL;
314                 }
315
316                 INIT_LIST_HEAD(&info->node_list);
317                 INIT_LIST_HEAD(&info->cluster_list);
318                 INIT_LIST_HEAD(&info->zone_list);
319
320                 /* Insert new sub-sequence */
321                 sseq = &nseq->sseqs[inspos];
322                 freesseq = &nseq->sseqs[nseq->first_free];
323                 memmove(sseq + 1, sseq, (freesseq - sseq) * sizeof(*sseq));
324                 memset(sseq, 0, sizeof(*sseq));
325                 nseq->first_free++;
326                 sseq->lower = lower;
327                 sseq->upper = upper;
328                 sseq->info = info;
329                 created_subseq = 1;
330         }
331
332         /* Insert a publication */
333         publ = publ_create(type, lower, upper, scope, node, port, key);
334         if (!publ)
335                 return NULL;
336
337         list_add(&publ->zone_list, &info->zone_list);
338         info->zone_list_size++;
339
340         if (in_own_cluster(node)) {
341                 list_add(&publ->cluster_list, &info->cluster_list);
342                 info->cluster_list_size++;
343         }
344
345         if (in_own_node(node)) {
346                 list_add(&publ->node_list, &info->node_list);
347                 info->node_list_size++;
348         }
349
350         /* Any subscriptions waiting for notification?  */
351         list_for_each_entry_safe(s, st, &nseq->subscriptions, nameseq_list) {
352                 tipc_subscr_report_overlap(s,
353                                            publ->lower,
354                                            publ->upper,
355                                            TIPC_PUBLISHED,
356                                            publ->ref,
357                                            publ->node,
358                                            created_subseq);
359         }
360         return publ;
361 }
362
363 /**
364  * tipc_nameseq_remove_publ
365  *
366  * NOTE: There may be cases where TIPC is asked to remove a publication
367  * that is not in the name table.  For example, if another node issues a
368  * publication for a name sequence that overlaps an existing name sequence
369  * the publication will not be recorded, which means the publication won't
370  * be found when the name sequence is later withdrawn by that node.
371  * A failed withdraw request simply returns a failure indication and lets the
372  * caller issue any error or warning messages associated with such a problem.
373  */
374 static struct publication *tipc_nameseq_remove_publ(struct name_seq *nseq, u32 inst,
375                                                     u32 node, u32 ref, u32 key)
376 {
377         struct publication *publ;
378         struct sub_seq *sseq = nameseq_find_subseq(nseq, inst);
379         struct name_info *info;
380         struct sub_seq *free;
381         struct tipc_subscription *s, *st;
382         int removed_subseq = 0;
383
384         if (!sseq)
385                 return NULL;
386
387         info = sseq->info;
388
389         /* Locate publication, if it exists */
390         list_for_each_entry(publ, &info->zone_list, zone_list) {
391                 if ((publ->key == key) && (publ->ref == ref) &&
392                     (!publ->node || (publ->node == node)))
393                         goto found;
394         }
395         return NULL;
396
397 found:
398         /* Remove publication from zone scope list */
399         list_del(&publ->zone_list);
400         info->zone_list_size--;
401
402         /* Remove publication from cluster scope list, if present */
403         if (in_own_cluster(node)) {
404                 list_del(&publ->cluster_list);
405                 info->cluster_list_size--;
406         }
407
408         /* Remove publication from node scope list, if present */
409         if (in_own_node(node)) {
410                 list_del(&publ->node_list);
411                 info->node_list_size--;
412         }
413
414         /* Contract subseq list if no more publications for that subseq */
415         if (list_empty(&info->zone_list)) {
416                 kfree(info);
417                 free = &nseq->sseqs[nseq->first_free--];
418                 memmove(sseq, sseq + 1, (free - (sseq + 1)) * sizeof(*sseq));
419                 removed_subseq = 1;
420         }
421
422         /* Notify any waiting subscriptions */
423         list_for_each_entry_safe(s, st, &nseq->subscriptions, nameseq_list) {
424                 tipc_subscr_report_overlap(s,
425                                            publ->lower,
426                                            publ->upper,
427                                            TIPC_WITHDRAWN,
428                                            publ->ref,
429                                            publ->node,
430                                            removed_subseq);
431         }
432
433         return publ;
434 }
435
436 /**
437  * tipc_nameseq_subscribe - attach a subscription, and issue
438  * the prescribed number of events if there is any sub-
439  * sequence overlapping with the requested sequence
440  */
441 static void tipc_nameseq_subscribe(struct name_seq *nseq,
442                                    struct tipc_subscription *s)
443 {
444         struct sub_seq *sseq = nseq->sseqs;
445
446         list_add(&s->nameseq_list, &nseq->subscriptions);
447
448         if (!sseq)
449                 return;
450
451         while (sseq != &nseq->sseqs[nseq->first_free]) {
452                 if (tipc_subscr_overlap(s, sseq->lower, sseq->upper)) {
453                         struct publication *crs;
454                         struct name_info *info = sseq->info;
455                         int must_report = 1;
456
457                         list_for_each_entry(crs, &info->zone_list, zone_list) {
458                                 tipc_subscr_report_overlap(s,
459                                                            sseq->lower,
460                                                            sseq->upper,
461                                                            TIPC_PUBLISHED,
462                                                            crs->ref,
463                                                            crs->node,
464                                                            must_report);
465                                 must_report = 0;
466                         }
467                 }
468                 sseq++;
469         }
470 }
471
472 static struct name_seq *nametbl_find_seq(u32 type)
473 {
474         struct hlist_head *seq_head;
475         struct name_seq *ns;
476
477         seq_head = &table.types[hash(type)];
478         hlist_for_each_entry(ns, seq_head, ns_list) {
479                 if (ns->type == type)
480                         return ns;
481         }
482
483         return NULL;
484 };
485
486 struct publication *tipc_nametbl_insert_publ(u32 type, u32 lower, u32 upper,
487                                              u32 scope, u32 node, u32 port, u32 key)
488 {
489         struct name_seq *seq = nametbl_find_seq(type);
490
491         if ((scope < TIPC_ZONE_SCOPE) || (scope > TIPC_NODE_SCOPE) ||
492             (lower > upper)) {
493                 pr_debug("Failed to publish illegal {%u,%u,%u} with scope %u\n",
494                          type, lower, upper, scope);
495                 return NULL;
496         }
497
498         if (!seq)
499                 seq = tipc_nameseq_create(type, &table.types[hash(type)]);
500         if (!seq)
501                 return NULL;
502
503         return tipc_nameseq_insert_publ(seq, type, lower, upper,
504                                         scope, node, port, key);
505 }
506
507 struct publication *tipc_nametbl_remove_publ(u32 type, u32 lower,
508                                              u32 node, u32 ref, u32 key)
509 {
510         struct publication *publ;
511         struct name_seq *seq = nametbl_find_seq(type);
512
513         if (!seq)
514                 return NULL;
515
516         publ = tipc_nameseq_remove_publ(seq, lower, node, ref, key);
517         nameseq_delete_empty(seq);
518         return publ;
519 }
520
521 /**
522  * tipc_nametbl_translate - perform name translation
523  *
524  * On entry, 'destnode' is the search domain used during translation.
525  *
526  * On exit:
527  * - if name translation is deferred to another node/cluster/zone,
528  *   leaves 'destnode' unchanged (will be non-zero) and returns 0
529  * - if name translation is attempted and succeeds, sets 'destnode'
530  *   to publishing node and returns port reference (will be non-zero)
531  * - if name translation is attempted and fails, sets 'destnode' to 0
532  *   and returns 0
533  */
534 u32 tipc_nametbl_translate(u32 type, u32 instance, u32 *destnode)
535 {
536         struct sub_seq *sseq;
537         struct name_info *info;
538         struct publication *publ;
539         struct name_seq *seq;
540         u32 ref = 0;
541         u32 node = 0;
542
543         if (!tipc_in_scope(*destnode, tipc_own_addr))
544                 return 0;
545
546         read_lock_bh(&tipc_nametbl_lock);
547         seq = nametbl_find_seq(type);
548         if (unlikely(!seq))
549                 goto not_found;
550         sseq = nameseq_find_subseq(seq, instance);
551         if (unlikely(!sseq))
552                 goto not_found;
553         spin_lock_bh(&seq->lock);
554         info = sseq->info;
555
556         /* Closest-First Algorithm */
557         if (likely(!*destnode)) {
558                 if (!list_empty(&info->node_list)) {
559                         publ = list_first_entry(&info->node_list,
560                                                 struct publication,
561                                                 node_list);
562                         list_move_tail(&publ->node_list,
563                                        &info->node_list);
564                 } else if (!list_empty(&info->cluster_list)) {
565                         publ = list_first_entry(&info->cluster_list,
566                                                 struct publication,
567                                                 cluster_list);
568                         list_move_tail(&publ->cluster_list,
569                                        &info->cluster_list);
570                 } else {
571                         publ = list_first_entry(&info->zone_list,
572                                                 struct publication,
573                                                 zone_list);
574                         list_move_tail(&publ->zone_list,
575                                        &info->zone_list);
576                 }
577         }
578
579         /* Round-Robin Algorithm */
580         else if (*destnode == tipc_own_addr) {
581                 if (list_empty(&info->node_list))
582                         goto no_match;
583                 publ = list_first_entry(&info->node_list, struct publication,
584                                         node_list);
585                 list_move_tail(&publ->node_list, &info->node_list);
586         } else if (in_own_cluster_exact(*destnode)) {
587                 if (list_empty(&info->cluster_list))
588                         goto no_match;
589                 publ = list_first_entry(&info->cluster_list, struct publication,
590                                         cluster_list);
591                 list_move_tail(&publ->cluster_list, &info->cluster_list);
592         } else {
593                 publ = list_first_entry(&info->zone_list, struct publication,
594                                         zone_list);
595                 list_move_tail(&publ->zone_list, &info->zone_list);
596         }
597
598         ref = publ->ref;
599         node = publ->node;
600 no_match:
601         spin_unlock_bh(&seq->lock);
602 not_found:
603         read_unlock_bh(&tipc_nametbl_lock);
604         *destnode = node;
605         return ref;
606 }
607
608 /**
609  * tipc_nametbl_mc_translate - find multicast destinations
610  *
611  * Creates list of all local ports that overlap the given multicast address;
612  * also determines if any off-node ports overlap.
613  *
614  * Note: Publications with a scope narrower than 'limit' are ignored.
615  * (i.e. local node-scope publications mustn't receive messages arriving
616  * from another node, even if the multcast link brought it here)
617  *
618  * Returns non-zero if any off-node ports overlap
619  */
620 int tipc_nametbl_mc_translate(u32 type, u32 lower, u32 upper, u32 limit,
621                               struct tipc_port_list *dports)
622 {
623         struct name_seq *seq;
624         struct sub_seq *sseq;
625         struct sub_seq *sseq_stop;
626         struct name_info *info;
627         int res = 0;
628
629         read_lock_bh(&tipc_nametbl_lock);
630         seq = nametbl_find_seq(type);
631         if (!seq)
632                 goto exit;
633
634         spin_lock_bh(&seq->lock);
635
636         sseq = seq->sseqs + nameseq_locate_subseq(seq, lower);
637         sseq_stop = seq->sseqs + seq->first_free;
638         for (; sseq != sseq_stop; sseq++) {
639                 struct publication *publ;
640
641                 if (sseq->lower > upper)
642                         break;
643
644                 info = sseq->info;
645                 list_for_each_entry(publ, &info->node_list, node_list) {
646                         if (publ->scope <= limit)
647                                 tipc_port_list_add(dports, publ->ref);
648                 }
649
650                 if (info->cluster_list_size != info->node_list_size)
651                         res = 1;
652         }
653
654         spin_unlock_bh(&seq->lock);
655 exit:
656         read_unlock_bh(&tipc_nametbl_lock);
657         return res;
658 }
659
660 /*
661  * tipc_nametbl_publish - add name publication to network name tables
662  */
663 struct publication *tipc_nametbl_publish(u32 type, u32 lower, u32 upper,
664                                          u32 scope, u32 port_ref, u32 key)
665 {
666         struct publication *publ;
667         struct sk_buff *buf = NULL;
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                 buf = tipc_named_publish(publ);
681         }
682         write_unlock_bh(&tipc_nametbl_lock);
683
684         if (buf)
685                 named_cluster_distribute(buf);
686         return publ;
687 }
688
689 /**
690  * tipc_nametbl_withdraw - withdraw name publication from network name tables
691  */
692 int tipc_nametbl_withdraw(u32 type, u32 lower, u32 ref, u32 key)
693 {
694         struct publication *publ;
695         struct sk_buff *buf;
696
697         write_lock_bh(&tipc_nametbl_lock);
698         publ = tipc_nametbl_remove_publ(type, lower, tipc_own_addr, ref, key);
699         if (likely(publ)) {
700                 table.local_publ_count--;
701                 buf = tipc_named_withdraw(publ);
702                 write_unlock_bh(&tipc_nametbl_lock);
703                 list_del_init(&publ->pport_list);
704                 kfree(publ);
705
706                 if (buf)
707                         named_cluster_distribute(buf);
708                 return 1;
709         }
710         write_unlock_bh(&tipc_nametbl_lock);
711         pr_err("Unable to remove local publication\n"
712                "(type=%u, lower=%u, ref=%u, key=%u)\n",
713                type, lower, ref, key);
714         return 0;
715 }
716
717 /**
718  * tipc_nametbl_subscribe - add a subscription object to the name table
719  */
720 void tipc_nametbl_subscribe(struct tipc_subscription *s)
721 {
722         u32 type = s->seq.type;
723         struct name_seq *seq;
724
725         write_lock_bh(&tipc_nametbl_lock);
726         seq = nametbl_find_seq(type);
727         if (!seq)
728                 seq = tipc_nameseq_create(type, &table.types[hash(type)]);
729         if (seq) {
730                 spin_lock_bh(&seq->lock);
731                 tipc_nameseq_subscribe(seq, s);
732                 spin_unlock_bh(&seq->lock);
733         } else {
734                 pr_warn("Failed to create subscription for {%u,%u,%u}\n",
735                         s->seq.type, s->seq.lower, s->seq.upper);
736         }
737         write_unlock_bh(&tipc_nametbl_lock);
738 }
739
740 /**
741  * tipc_nametbl_unsubscribe - remove a subscription object from name table
742  */
743 void tipc_nametbl_unsubscribe(struct tipc_subscription *s)
744 {
745         struct name_seq *seq;
746
747         write_lock_bh(&tipc_nametbl_lock);
748         seq = nametbl_find_seq(s->seq.type);
749         if (seq != NULL) {
750                 spin_lock_bh(&seq->lock);
751                 list_del_init(&s->nameseq_list);
752                 spin_unlock_bh(&seq->lock);
753                 nameseq_delete_empty(seq);
754         }
755         write_unlock_bh(&tipc_nametbl_lock);
756 }
757
758
759 /**
760  * subseq_list - print specified sub-sequence contents into the given buffer
761  */
762 static int subseq_list(struct sub_seq *sseq, char *buf, int len, u32 depth,
763                        u32 index)
764 {
765         char portIdStr[27];
766         const char *scope_str[] = {"", " zone", " cluster", " node"};
767         struct publication *publ;
768         struct name_info *info;
769         int ret;
770
771         ret = tipc_snprintf(buf, len, "%-10u %-10u ", sseq->lower, sseq->upper);
772
773         if (depth == 2) {
774                 ret += tipc_snprintf(buf - ret, len + ret, "\n");
775                 return ret;
776         }
777
778         info = sseq->info;
779
780         list_for_each_entry(publ, &info->zone_list, zone_list) {
781                 sprintf(portIdStr, "<%u.%u.%u:%u>",
782                          tipc_zone(publ->node), tipc_cluster(publ->node),
783                          tipc_node(publ->node), publ->ref);
784                 ret += tipc_snprintf(buf + ret, len - ret, "%-26s ", portIdStr);
785                 if (depth > 3) {
786                         ret += tipc_snprintf(buf + ret, len - ret, "%-10u %s",
787                                              publ->key, scope_str[publ->scope]);
788                 }
789                 if (!list_is_last(&publ->zone_list, &info->zone_list))
790                         ret += tipc_snprintf(buf + ret, len - ret,
791                                              "\n%33s", " ");
792         }
793
794         ret += tipc_snprintf(buf + ret, len - ret, "\n");
795         return ret;
796 }
797
798 /**
799  * nameseq_list - print specified name sequence contents into the given buffer
800  */
801 static int nameseq_list(struct name_seq *seq, char *buf, int len, u32 depth,
802                         u32 type, u32 lowbound, u32 upbound, u32 index)
803 {
804         struct sub_seq *sseq;
805         char typearea[11];
806         int ret = 0;
807
808         if (seq->first_free == 0)
809                 return 0;
810
811         sprintf(typearea, "%-10u", seq->type);
812
813         if (depth == 1) {
814                 ret += tipc_snprintf(buf, len, "%s\n", typearea);
815                 return ret;
816         }
817
818         for (sseq = seq->sseqs; sseq != &seq->sseqs[seq->first_free]; sseq++) {
819                 if ((lowbound <= sseq->upper) && (upbound >= sseq->lower)) {
820                         ret += tipc_snprintf(buf + ret, len - ret, "%s ",
821                                             typearea);
822                         spin_lock_bh(&seq->lock);
823                         ret += subseq_list(sseq, buf + ret, len - ret,
824                                           depth, index);
825                         spin_unlock_bh(&seq->lock);
826                         sprintf(typearea, "%10s", " ");
827                 }
828         }
829         return ret;
830 }
831
832 /**
833  * nametbl_header - print name table header into the given buffer
834  */
835 static int nametbl_header(char *buf, int len, u32 depth)
836 {
837         const char *header[] = {
838                 "Type       ",
839                 "Lower      Upper      ",
840                 "Port Identity              ",
841                 "Publication Scope"
842         };
843
844         int i;
845         int ret = 0;
846
847         if (depth > 4)
848                 depth = 4;
849         for (i = 0; i < depth; i++)
850                 ret += tipc_snprintf(buf + ret, len - ret, header[i]);
851         ret += tipc_snprintf(buf + ret, len - ret, "\n");
852         return ret;
853 }
854
855 /**
856  * nametbl_list - print specified name table contents into the given buffer
857  */
858 static int nametbl_list(char *buf, int len, u32 depth_info,
859                         u32 type, u32 lowbound, u32 upbound)
860 {
861         struct hlist_head *seq_head;
862         struct name_seq *seq;
863         int all_types;
864         int ret = 0;
865         u32 depth;
866         u32 i;
867
868         all_types = (depth_info & TIPC_NTQ_ALLTYPES);
869         depth = (depth_info & ~TIPC_NTQ_ALLTYPES);
870
871         if (depth == 0)
872                 return 0;
873
874         if (all_types) {
875                 /* display all entries in name table to specified depth */
876                 ret += nametbl_header(buf, len, depth);
877                 lowbound = 0;
878                 upbound = ~0;
879                 for (i = 0; i < TIPC_NAMETBL_SIZE; i++) {
880                         seq_head = &table.types[i];
881                         hlist_for_each_entry(seq, seq_head, ns_list) {
882                                 ret += nameseq_list(seq, buf + ret, len - ret,
883                                                    depth, seq->type,
884                                                    lowbound, upbound, i);
885                         }
886                 }
887         } else {
888                 /* display only the sequence that matches the specified type */
889                 if (upbound < lowbound) {
890                         ret += tipc_snprintf(buf + ret, len - ret,
891                                         "invalid name sequence specified\n");
892                         return ret;
893                 }
894                 ret += nametbl_header(buf + ret, len - ret, depth);
895                 i = hash(type);
896                 seq_head = &table.types[i];
897                 hlist_for_each_entry(seq, seq_head, ns_list) {
898                         if (seq->type == type) {
899                                 ret += nameseq_list(seq, buf + ret, len - ret,
900                                                    depth, type,
901                                                    lowbound, upbound, i);
902                                 break;
903                         }
904                 }
905         }
906         return ret;
907 }
908
909 struct sk_buff *tipc_nametbl_get(const void *req_tlv_area, int req_tlv_space)
910 {
911         struct sk_buff *buf;
912         struct tipc_name_table_query *argv;
913         struct tlv_desc *rep_tlv;
914         char *pb;
915         int pb_len;
916         int str_len;
917
918         if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NAME_TBL_QUERY))
919                 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
920
921         buf = tipc_cfg_reply_alloc(TLV_SPACE(ULTRA_STRING_MAX_LEN));
922         if (!buf)
923                 return NULL;
924
925         rep_tlv = (struct tlv_desc *)buf->data;
926         pb = TLV_DATA(rep_tlv);
927         pb_len = ULTRA_STRING_MAX_LEN;
928         argv = (struct tipc_name_table_query *)TLV_DATA(req_tlv_area);
929         read_lock_bh(&tipc_nametbl_lock);
930         str_len = nametbl_list(pb, pb_len, ntohl(argv->depth),
931                                ntohl(argv->type),
932                                ntohl(argv->lowbound), ntohl(argv->upbound));
933         read_unlock_bh(&tipc_nametbl_lock);
934         str_len += 1;   /* for "\0" */
935         skb_put(buf, TLV_SPACE(str_len));
936         TLV_SET(rep_tlv, TIPC_TLV_ULTRA_STRING, NULL, str_len);
937
938         return buf;
939 }
940
941 int tipc_nametbl_init(void)
942 {
943         table.types = kcalloc(TIPC_NAMETBL_SIZE, sizeof(struct hlist_head),
944                               GFP_ATOMIC);
945         if (!table.types)
946                 return -ENOMEM;
947
948         table.local_publ_count = 0;
949         return 0;
950 }
951
952 /**
953  * tipc_purge_publications - remove all publications for a given type
954  *
955  * tipc_nametbl_lock must be held when calling this function
956  */
957 static void tipc_purge_publications(struct name_seq *seq)
958 {
959         struct publication *publ, *safe;
960         struct sub_seq *sseq;
961         struct name_info *info;
962
963         if (!seq->sseqs) {
964                 nameseq_delete_empty(seq);
965                 return;
966         }
967         sseq = seq->sseqs;
968         info = sseq->info;
969         list_for_each_entry_safe(publ, safe, &info->zone_list, zone_list) {
970                 tipc_nametbl_remove_publ(publ->type, publ->lower, publ->node,
971                                          publ->ref, publ->key);
972                 kfree(publ);
973         }
974 }
975
976 void tipc_nametbl_stop(void)
977 {
978         u32 i;
979         struct name_seq *seq;
980         struct hlist_head *seq_head;
981         struct hlist_node *safe;
982
983         /* Verify name table is empty and purge any lingering
984          * publications, then release the name table
985          */
986         write_lock_bh(&tipc_nametbl_lock);
987         for (i = 0; i < TIPC_NAMETBL_SIZE; i++) {
988                 if (hlist_empty(&table.types[i]))
989                         continue;
990                 seq_head = &table.types[i];
991                 hlist_for_each_entry_safe(seq, safe, seq_head, ns_list) {
992                         tipc_purge_publications(seq);
993                 }
994         }
995         kfree(table.types);
996         table.types = NULL;
997         write_unlock_bh(&tipc_nametbl_lock);
998 }