xref: /openbmc/linux/net/tipc/name_table.c (revision 22246614)
1 /*
2  * net/tipc/name_table.c: TIPC name table code
3  *
4  * Copyright (c) 2000-2006, Ericsson AB
5  * Copyright (c) 2004-2005, 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 "dbg.h"
40 #include "name_table.h"
41 #include "name_distr.h"
42 #include "addr.h"
43 #include "node_subscr.h"
44 #include "subscr.h"
45 #include "port.h"
46 #include "cluster.h"
47 #include "bcast.h"
48 
49 static int tipc_nametbl_size = 1024;		/* must be a power of 2 */
50 
51 /**
52  * struct sub_seq - container for all published instances of a name sequence
53  * @lower: name sequence lower bound
54  * @upper: name sequence upper bound
55  * @node_list: circular list of matching publications with >= node scope
56  * @cluster_list: circular list of matching publications with >= cluster scope
57  * @zone_list: circular list of matching publications with >= zone scope
58  */
59 
60 struct sub_seq {
61 	u32 lower;
62 	u32 upper;
63 	struct publication *node_list;
64 	struct publication *cluster_list;
65 	struct publication *zone_list;
66 };
67 
68 /**
69  * struct name_seq - container for all published instances of a name type
70  * @type: 32 bit 'type' value for name sequence
71  * @sseq: pointer to dynamically-sized array of sub-sequences of this 'type';
72  *        sub-sequences are sorted in ascending order
73  * @alloc: number of sub-sequences currently in array
74  * @first_free: array index of first unused sub-sequence entry
75  * @ns_list: links to adjacent name sequences in hash chain
76  * @subscriptions: list of subscriptions for this 'type'
77  * @lock: spinlock controlling access to name sequence structure
78  */
79 
80 struct name_seq {
81 	u32 type;
82 	struct sub_seq *sseqs;
83 	u32 alloc;
84 	u32 first_free;
85 	struct hlist_node ns_list;
86 	struct list_head subscriptions;
87 	spinlock_t lock;
88 };
89 
90 /**
91  * struct name_table - table containing all existing port name publications
92  * @types: pointer to fixed-sized array of name sequence lists,
93  *         accessed via hashing on 'type'; name sequence lists are *not* sorted
94  * @local_publ_count: number of publications issued by this node
95  */
96 
97 struct name_table {
98 	struct hlist_head *types;
99 	u32 local_publ_count;
100 };
101 
102 static struct name_table table = { NULL } ;
103 static atomic_t rsv_publ_ok = ATOMIC_INIT(0);
104 DEFINE_RWLOCK(tipc_nametbl_lock);
105 
106 
107 static int hash(int x)
108 {
109 	return(x & (tipc_nametbl_size - 1));
110 }
111 
112 /**
113  * publ_create - create a publication structure
114  */
115 
116 static struct publication *publ_create(u32 type, u32 lower, u32 upper,
117 				       u32 scope, u32 node, u32 port_ref,
118 				       u32 key)
119 {
120 	struct publication *publ = kzalloc(sizeof(*publ), GFP_ATOMIC);
121 	if (publ == NULL) {
122 		warn("Publication creation failure, no memory\n");
123 		return NULL;
124 	}
125 
126 	publ->type = type;
127 	publ->lower = lower;
128 	publ->upper = upper;
129 	publ->scope = scope;
130 	publ->node = node;
131 	publ->ref = port_ref;
132 	publ->key = key;
133 	INIT_LIST_HEAD(&publ->local_list);
134 	INIT_LIST_HEAD(&publ->pport_list);
135 	INIT_LIST_HEAD(&publ->subscr.nodesub_list);
136 	return publ;
137 }
138 
139 /**
140  * tipc_subseq_alloc - allocate a specified number of sub-sequence structures
141  */
142 
143 static struct sub_seq *tipc_subseq_alloc(u32 cnt)
144 {
145 	struct sub_seq *sseq = kcalloc(cnt, sizeof(struct sub_seq), GFP_ATOMIC);
146 	return sseq;
147 }
148 
149 /**
150  * tipc_nameseq_create - create a name sequence structure for the specified 'type'
151  *
152  * Allocates a single sub-sequence structure and sets it to all 0's.
153  */
154 
155 static struct name_seq *tipc_nameseq_create(u32 type, struct hlist_head *seq_head)
156 {
157 	struct name_seq *nseq = kzalloc(sizeof(*nseq), GFP_ATOMIC);
158 	struct sub_seq *sseq = tipc_subseq_alloc(1);
159 
160 	if (!nseq || !sseq) {
161 		warn("Name sequence creation failed, no memory\n");
162 		kfree(nseq);
163 		kfree(sseq);
164 		return NULL;
165 	}
166 
167 	spin_lock_init(&nseq->lock);
168 	nseq->type = type;
169 	nseq->sseqs = sseq;
170 	dbg("tipc_nameseq_create(): nseq = %p, type %u, ssseqs %p, ff: %u\n",
171 	    nseq, type, nseq->sseqs, nseq->first_free);
172 	nseq->alloc = 1;
173 	INIT_HLIST_NODE(&nseq->ns_list);
174 	INIT_LIST_HEAD(&nseq->subscriptions);
175 	hlist_add_head(&nseq->ns_list, seq_head);
176 	return nseq;
177 }
178 
179 /**
180  * nameseq_find_subseq - find sub-sequence (if any) matching a name instance
181  *
182  * Very time-critical, so binary searches through sub-sequence array.
183  */
184 
185 static struct sub_seq *nameseq_find_subseq(struct name_seq *nseq,
186 					   u32 instance)
187 {
188 	struct sub_seq *sseqs = nseq->sseqs;
189 	int low = 0;
190 	int high = nseq->first_free - 1;
191 	int mid;
192 
193 	while (low <= high) {
194 		mid = (low + high) / 2;
195 		if (instance < sseqs[mid].lower)
196 			high = mid - 1;
197 		else if (instance > sseqs[mid].upper)
198 			low = mid + 1;
199 		else
200 			return &sseqs[mid];
201 	}
202 	return NULL;
203 }
204 
205 /**
206  * nameseq_locate_subseq - determine position of name instance in sub-sequence
207  *
208  * Returns index in sub-sequence array of the entry that contains the specified
209  * instance value; if no entry contains that value, returns the position
210  * where a new entry for it would be inserted in the array.
211  *
212  * Note: Similar to binary search code for locating a sub-sequence.
213  */
214 
215 static u32 nameseq_locate_subseq(struct name_seq *nseq, u32 instance)
216 {
217 	struct sub_seq *sseqs = nseq->sseqs;
218 	int low = 0;
219 	int high = nseq->first_free - 1;
220 	int mid;
221 
222 	while (low <= high) {
223 		mid = (low + high) / 2;
224 		if (instance < sseqs[mid].lower)
225 			high = mid - 1;
226 		else if (instance > sseqs[mid].upper)
227 			low = mid + 1;
228 		else
229 			return mid;
230 	}
231 	return low;
232 }
233 
234 /**
235  * tipc_nameseq_insert_publ -
236  */
237 
238 static struct publication *tipc_nameseq_insert_publ(struct name_seq *nseq,
239 						    u32 type, u32 lower, u32 upper,
240 						    u32 scope, u32 node, u32 port, u32 key)
241 {
242 	struct subscription *s;
243 	struct subscription *st;
244 	struct publication *publ;
245 	struct sub_seq *sseq;
246 	int created_subseq = 0;
247 
248 	sseq = nameseq_find_subseq(nseq, lower);
249 	dbg("nameseq_ins: for seq %p, {%u,%u}, found sseq %p\n",
250 	    nseq, type, lower, sseq);
251 	if (sseq) {
252 
253 		/* Lower end overlaps existing entry => need an exact match */
254 
255 		if ((sseq->lower != lower) || (sseq->upper != upper)) {
256 			warn("Cannot publish {%u,%u,%u}, overlap error\n",
257 			     type, lower, upper);
258 			return NULL;
259 		}
260 	} else {
261 		u32 inspos;
262 		struct sub_seq *freesseq;
263 
264 		/* Find where lower end should be inserted */
265 
266 		inspos = nameseq_locate_subseq(nseq, lower);
267 
268 		/* Fail if upper end overlaps into an existing entry */
269 
270 		if ((inspos < nseq->first_free) &&
271 		    (upper >= nseq->sseqs[inspos].lower)) {
272 			warn("Cannot publish {%u,%u,%u}, overlap error\n",
273 			     type, lower, upper);
274 			return NULL;
275 		}
276 
277 		/* Ensure there is space for new sub-sequence */
278 
279 		if (nseq->first_free == nseq->alloc) {
280 			struct sub_seq *sseqs = tipc_subseq_alloc(nseq->alloc * 2);
281 
282 			if (!sseqs) {
283 				warn("Cannot publish {%u,%u,%u}, no memory\n",
284 				     type, lower, upper);
285 				return NULL;
286 			}
287 			dbg("Allocated %u more sseqs\n", nseq->alloc);
288 			memcpy(sseqs, nseq->sseqs,
289 			       nseq->alloc * sizeof(struct sub_seq));
290 			kfree(nseq->sseqs);
291 			nseq->sseqs = sseqs;
292 			nseq->alloc *= 2;
293 		}
294 		dbg("Have %u sseqs for type %u\n", nseq->alloc, type);
295 
296 		/* Insert new sub-sequence */
297 
298 		dbg("ins in pos %u, ff = %u\n", inspos, nseq->first_free);
299 		sseq = &nseq->sseqs[inspos];
300 		freesseq = &nseq->sseqs[nseq->first_free];
301 		memmove(sseq + 1, sseq, (freesseq - sseq) * sizeof (*sseq));
302 		memset(sseq, 0, sizeof (*sseq));
303 		nseq->first_free++;
304 		sseq->lower = lower;
305 		sseq->upper = upper;
306 		created_subseq = 1;
307 	}
308 	dbg("inserting {%u,%u,%u} from <0x%x:%u> into sseq %p(%u,%u) of seq %p\n",
309 	    type, lower, upper, node, port, sseq,
310 	    sseq->lower, sseq->upper, nseq);
311 
312 	/* Insert a publication: */
313 
314 	publ = publ_create(type, lower, upper, scope, node, port, key);
315 	if (!publ)
316 		return NULL;
317 	dbg("inserting publ %p, node=0x%x publ->node=0x%x, subscr->node=%p\n",
318 	    publ, node, publ->node, publ->subscr.node);
319 
320 	if (!sseq->zone_list)
321 		sseq->zone_list = publ->zone_list_next = publ;
322 	else {
323 		publ->zone_list_next = sseq->zone_list->zone_list_next;
324 		sseq->zone_list->zone_list_next = publ;
325 	}
326 
327 	if (in_own_cluster(node)) {
328 		if (!sseq->cluster_list)
329 			sseq->cluster_list = publ->cluster_list_next = publ;
330 		else {
331 			publ->cluster_list_next =
332 			sseq->cluster_list->cluster_list_next;
333 			sseq->cluster_list->cluster_list_next = publ;
334 		}
335 	}
336 
337 	if (node == tipc_own_addr) {
338 		if (!sseq->node_list)
339 			sseq->node_list = publ->node_list_next = publ;
340 		else {
341 			publ->node_list_next = sseq->node_list->node_list_next;
342 			sseq->node_list->node_list_next = publ;
343 		}
344 	}
345 
346 	/*
347 	 * Any subscriptions waiting for notification?
348 	 */
349 	list_for_each_entry_safe(s, st, &nseq->subscriptions, nameseq_list) {
350 		dbg("calling report_overlap()\n");
351 		tipc_subscr_report_overlap(s,
352 					   publ->lower,
353 					   publ->upper,
354 					   TIPC_PUBLISHED,
355 					   publ->ref,
356 					   publ->node,
357 					   created_subseq);
358 	}
359 	return publ;
360 }
361 
362 /**
363  * tipc_nameseq_remove_publ -
364  *
365  * NOTE: There may be cases where TIPC is asked to remove a publication
366  * that is not in the name table.  For example, if another node issues a
367  * publication for a name sequence that overlaps an existing name sequence
368  * the publication will not be recorded, which means the publication won't
369  * be found when the name sequence is later withdrawn by that node.
370  * A failed withdraw request simply returns a failure indication and lets the
371  * caller issue any error or warning messages associated with such a problem.
372  */
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 publication *curr;
379 	struct publication *prev;
380 	struct sub_seq *sseq = nameseq_find_subseq(nseq, inst);
381 	struct sub_seq *free;
382 	struct subscription *s, *st;
383 	int removed_subseq = 0;
384 
385 	if (!sseq)
386 		return NULL;
387 
388 	dbg("tipc_nameseq_remove_publ: seq: %p, sseq %p, {%u,%u}, key %u\n",
389 	    nseq, sseq, nseq->type, inst, key);
390 
391 	/* Remove publication from zone scope list */
392 
393 	prev = sseq->zone_list;
394 	publ = sseq->zone_list->zone_list_next;
395 	while ((publ->key != key) || (publ->ref != ref) ||
396 	       (publ->node && (publ->node != node))) {
397 		prev = publ;
398 		publ = publ->zone_list_next;
399 		if (prev == sseq->zone_list) {
400 
401 			/* Prevent endless loop if publication not found */
402 
403 			return NULL;
404 		}
405 	}
406 	if (publ != sseq->zone_list)
407 		prev->zone_list_next = publ->zone_list_next;
408 	else if (publ->zone_list_next != publ) {
409 		prev->zone_list_next = publ->zone_list_next;
410 		sseq->zone_list = publ->zone_list_next;
411 	} else {
412 		sseq->zone_list = NULL;
413 	}
414 
415 	/* Remove publication from cluster scope list, if present */
416 
417 	if (in_own_cluster(node)) {
418 		prev = sseq->cluster_list;
419 		curr = sseq->cluster_list->cluster_list_next;
420 		while (curr != publ) {
421 			prev = curr;
422 			curr = curr->cluster_list_next;
423 			if (prev == sseq->cluster_list) {
424 
425 				/* Prevent endless loop for malformed list */
426 
427 				err("Unable to de-list cluster publication\n"
428 				    "{%u%u}, node=0x%x, ref=%u, key=%u)\n",
429 				    publ->type, publ->lower, publ->node,
430 				    publ->ref, publ->key);
431 				goto end_cluster;
432 			}
433 		}
434 		if (publ != sseq->cluster_list)
435 			prev->cluster_list_next = publ->cluster_list_next;
436 		else if (publ->cluster_list_next != publ) {
437 			prev->cluster_list_next = publ->cluster_list_next;
438 			sseq->cluster_list = publ->cluster_list_next;
439 		} else {
440 			sseq->cluster_list = NULL;
441 		}
442 	}
443 end_cluster:
444 
445 	/* Remove publication from node scope list, if present */
446 
447 	if (node == tipc_own_addr) {
448 		prev = sseq->node_list;
449 		curr = sseq->node_list->node_list_next;
450 		while (curr != publ) {
451 			prev = curr;
452 			curr = curr->node_list_next;
453 			if (prev == sseq->node_list) {
454 
455 				/* Prevent endless loop for malformed list */
456 
457 				err("Unable to de-list node publication\n"
458 				    "{%u%u}, node=0x%x, ref=%u, key=%u)\n",
459 				    publ->type, publ->lower, publ->node,
460 				    publ->ref, publ->key);
461 				goto end_node;
462 			}
463 		}
464 		if (publ != sseq->node_list)
465 			prev->node_list_next = publ->node_list_next;
466 		else if (publ->node_list_next != publ) {
467 			prev->node_list_next = publ->node_list_next;
468 			sseq->node_list = publ->node_list_next;
469 		} else {
470 			sseq->node_list = NULL;
471 		}
472 	}
473 end_node:
474 
475 	/* Contract subseq list if no more publications for that subseq */
476 
477 	if (!sseq->zone_list) {
478 		free = &nseq->sseqs[nseq->first_free--];
479 		memmove(sseq, sseq + 1, (free - (sseq + 1)) * sizeof (*sseq));
480 		removed_subseq = 1;
481 	}
482 
483 	/* Notify any waiting subscriptions */
484 
485 	list_for_each_entry_safe(s, st, &nseq->subscriptions, nameseq_list) {
486 		tipc_subscr_report_overlap(s,
487 					   publ->lower,
488 					   publ->upper,
489 					   TIPC_WITHDRAWN,
490 					   publ->ref,
491 					   publ->node,
492 					   removed_subseq);
493 	}
494 
495 	return publ;
496 }
497 
498 /**
499  * tipc_nameseq_subscribe: attach a subscription, and issue
500  * the prescribed number of events if there is any sub-
501  * sequence overlapping with the requested sequence
502  */
503 
504 static void tipc_nameseq_subscribe(struct name_seq *nseq, struct subscription *s)
505 {
506 	struct sub_seq *sseq = nseq->sseqs;
507 
508 	list_add(&s->nameseq_list, &nseq->subscriptions);
509 
510 	if (!sseq)
511 		return;
512 
513 	while (sseq != &nseq->sseqs[nseq->first_free]) {
514 		struct publication *zl = sseq->zone_list;
515 		if (zl && tipc_subscr_overlap(s,sseq->lower,sseq->upper)) {
516 			struct publication *crs = zl;
517 			int must_report = 1;
518 
519 			do {
520 				tipc_subscr_report_overlap(s,
521 							   sseq->lower,
522 							   sseq->upper,
523 							   TIPC_PUBLISHED,
524 							   crs->ref,
525 							   crs->node,
526 							   must_report);
527 				must_report = 0;
528 				crs = crs->zone_list_next;
529 			} while (crs != zl);
530 		}
531 		sseq++;
532 	}
533 }
534 
535 static struct name_seq *nametbl_find_seq(u32 type)
536 {
537 	struct hlist_head *seq_head;
538 	struct hlist_node *seq_node;
539 	struct name_seq *ns;
540 
541 	dbg("find_seq %u,(%u,0x%x) table = %p, hash[type] = %u\n",
542 	    type, ntohl(type), type, table.types, hash(type));
543 
544 	seq_head = &table.types[hash(type)];
545 	hlist_for_each_entry(ns, seq_node, seq_head, ns_list) {
546 		if (ns->type == type) {
547 			dbg("found %p\n", ns);
548 			return ns;
549 		}
550 	}
551 
552 	return NULL;
553 };
554 
555 struct publication *tipc_nametbl_insert_publ(u32 type, u32 lower, u32 upper,
556 					     u32 scope, u32 node, u32 port, u32 key)
557 {
558 	struct name_seq *seq = nametbl_find_seq(type);
559 
560 	dbg("tipc_nametbl_insert_publ: {%u,%u,%u} found %p\n", type, lower, upper, seq);
561 	if (lower > upper) {
562 		warn("Failed to publish illegal {%u,%u,%u}\n",
563 		     type, lower, upper);
564 		return NULL;
565 	}
566 
567 	dbg("Publishing {%u,%u,%u} from 0x%x\n", type, lower, upper, node);
568 	if (!seq) {
569 		seq = tipc_nameseq_create(type, &table.types[hash(type)]);
570 		dbg("tipc_nametbl_insert_publ: created %p\n", seq);
571 	}
572 	if (!seq)
573 		return NULL;
574 
575 	return tipc_nameseq_insert_publ(seq, type, lower, upper,
576 					scope, node, port, key);
577 }
578 
579 struct publication *tipc_nametbl_remove_publ(u32 type, u32 lower,
580 					     u32 node, u32 ref, u32 key)
581 {
582 	struct publication *publ;
583 	struct name_seq *seq = nametbl_find_seq(type);
584 
585 	if (!seq)
586 		return NULL;
587 
588 	dbg("Withdrawing {%u,%u} from 0x%x\n", type, lower, node);
589 	publ = tipc_nameseq_remove_publ(seq, lower, node, ref, key);
590 
591 	if (!seq->first_free && list_empty(&seq->subscriptions)) {
592 		hlist_del_init(&seq->ns_list);
593 		kfree(seq->sseqs);
594 		kfree(seq);
595 	}
596 	return publ;
597 }
598 
599 /*
600  * tipc_nametbl_translate(): Translate tipc_name -> tipc_portid.
601  *                      Very time-critical.
602  *
603  * Note: on entry 'destnode' is the search domain used during translation;
604  *       on exit it passes back the node address of the matching port (if any)
605  */
606 
607 u32 tipc_nametbl_translate(u32 type, u32 instance, u32 *destnode)
608 {
609 	struct sub_seq *sseq;
610 	struct publication *publ = NULL;
611 	struct name_seq *seq;
612 	u32 ref;
613 
614 	if (!in_scope(*destnode, tipc_own_addr))
615 		return 0;
616 
617 	read_lock_bh(&tipc_nametbl_lock);
618 	seq = nametbl_find_seq(type);
619 	if (unlikely(!seq))
620 		goto not_found;
621 	sseq = nameseq_find_subseq(seq, instance);
622 	if (unlikely(!sseq))
623 		goto not_found;
624 	spin_lock_bh(&seq->lock);
625 
626 	/* Closest-First Algorithm: */
627 	if (likely(!*destnode)) {
628 		publ = sseq->node_list;
629 		if (publ) {
630 			sseq->node_list = publ->node_list_next;
631 found:
632 			ref = publ->ref;
633 			*destnode = publ->node;
634 			spin_unlock_bh(&seq->lock);
635 			read_unlock_bh(&tipc_nametbl_lock);
636 			return ref;
637 		}
638 		publ = sseq->cluster_list;
639 		if (publ) {
640 			sseq->cluster_list = publ->cluster_list_next;
641 			goto found;
642 		}
643 		publ = sseq->zone_list;
644 		if (publ) {
645 			sseq->zone_list = publ->zone_list_next;
646 			goto found;
647 		}
648 	}
649 
650 	/* Round-Robin Algorithm: */
651 	else if (*destnode == tipc_own_addr) {
652 		publ = sseq->node_list;
653 		if (publ) {
654 			sseq->node_list = publ->node_list_next;
655 			goto found;
656 		}
657 	} else if (in_own_cluster(*destnode)) {
658 		publ = sseq->cluster_list;
659 		if (publ) {
660 			sseq->cluster_list = publ->cluster_list_next;
661 			goto found;
662 		}
663 	} else {
664 		publ = sseq->zone_list;
665 		if (publ) {
666 			sseq->zone_list = publ->zone_list_next;
667 			goto found;
668 		}
669 	}
670 	spin_unlock_bh(&seq->lock);
671 not_found:
672 	*destnode = 0;
673 	read_unlock_bh(&tipc_nametbl_lock);
674 	return 0;
675 }
676 
677 /**
678  * tipc_nametbl_mc_translate - find multicast destinations
679  *
680  * Creates list of all local ports that overlap the given multicast address;
681  * also determines if any off-node ports overlap.
682  *
683  * Note: Publications with a scope narrower than 'limit' are ignored.
684  * (i.e. local node-scope publications mustn't receive messages arriving
685  * from another node, even if the multcast link brought it here)
686  *
687  * Returns non-zero if any off-node ports overlap
688  */
689 
690 int tipc_nametbl_mc_translate(u32 type, u32 lower, u32 upper, u32 limit,
691 			      struct port_list *dports)
692 {
693 	struct name_seq *seq;
694 	struct sub_seq *sseq;
695 	struct sub_seq *sseq_stop;
696 	int res = 0;
697 
698 	read_lock_bh(&tipc_nametbl_lock);
699 	seq = nametbl_find_seq(type);
700 	if (!seq)
701 		goto exit;
702 
703 	spin_lock_bh(&seq->lock);
704 
705 	sseq = seq->sseqs + nameseq_locate_subseq(seq, lower);
706 	sseq_stop = seq->sseqs + seq->first_free;
707 	for (; sseq != sseq_stop; sseq++) {
708 		struct publication *publ;
709 
710 		if (sseq->lower > upper)
711 			break;
712 		publ = sseq->cluster_list;
713 		if (publ && (publ->scope <= limit))
714 			do {
715 				if (publ->node == tipc_own_addr)
716 					tipc_port_list_add(dports, publ->ref);
717 				else
718 					res = 1;
719 				publ = publ->cluster_list_next;
720 			} while (publ != sseq->cluster_list);
721 	}
722 
723 	spin_unlock_bh(&seq->lock);
724 exit:
725 	read_unlock_bh(&tipc_nametbl_lock);
726 	return res;
727 }
728 
729 /**
730  * tipc_nametbl_publish_rsv - publish port name using a reserved name type
731  */
732 
733 int tipc_nametbl_publish_rsv(u32 ref, unsigned int scope,
734 			struct tipc_name_seq const *seq)
735 {
736 	int res;
737 
738 	atomic_inc(&rsv_publ_ok);
739 	res = tipc_publish(ref, scope, seq);
740 	atomic_dec(&rsv_publ_ok);
741 	return res;
742 }
743 
744 /**
745  * tipc_nametbl_publish - add name publication to network name tables
746  */
747 
748 struct publication *tipc_nametbl_publish(u32 type, u32 lower, u32 upper,
749 				    u32 scope, u32 port_ref, u32 key)
750 {
751 	struct publication *publ;
752 
753 	if (table.local_publ_count >= tipc_max_publications) {
754 		warn("Publication failed, local publication limit reached (%u)\n",
755 		     tipc_max_publications);
756 		return NULL;
757 	}
758 	if ((type < TIPC_RESERVED_TYPES) && !atomic_read(&rsv_publ_ok)) {
759 		warn("Publication failed, reserved name {%u,%u,%u}\n",
760 		     type, lower, upper);
761 		return NULL;
762 	}
763 
764 	write_lock_bh(&tipc_nametbl_lock);
765 	table.local_publ_count++;
766 	publ = tipc_nametbl_insert_publ(type, lower, upper, scope,
767 				   tipc_own_addr, port_ref, key);
768 	if (publ && (scope != TIPC_NODE_SCOPE)) {
769 		tipc_named_publish(publ);
770 	}
771 	write_unlock_bh(&tipc_nametbl_lock);
772 	return publ;
773 }
774 
775 /**
776  * tipc_nametbl_withdraw - withdraw name publication from network name tables
777  */
778 
779 int tipc_nametbl_withdraw(u32 type, u32 lower, u32 ref, u32 key)
780 {
781 	struct publication *publ;
782 
783 	dbg("tipc_nametbl_withdraw: {%u,%u}, key=%u\n", type, lower, key);
784 	write_lock_bh(&tipc_nametbl_lock);
785 	publ = tipc_nametbl_remove_publ(type, lower, tipc_own_addr, ref, key);
786 	if (likely(publ)) {
787 		table.local_publ_count--;
788 		if (publ->scope != TIPC_NODE_SCOPE)
789 			tipc_named_withdraw(publ);
790 		write_unlock_bh(&tipc_nametbl_lock);
791 		list_del_init(&publ->pport_list);
792 		kfree(publ);
793 		return 1;
794 	}
795 	write_unlock_bh(&tipc_nametbl_lock);
796 	err("Unable to remove local publication\n"
797 	    "(type=%u, lower=%u, ref=%u, key=%u)\n",
798 	    type, lower, ref, key);
799 	return 0;
800 }
801 
802 /**
803  * tipc_nametbl_subscribe - add a subscription object to the name table
804  */
805 
806 void tipc_nametbl_subscribe(struct subscription *s)
807 {
808 	u32 type = s->seq.type;
809 	struct name_seq *seq;
810 
811 	write_lock_bh(&tipc_nametbl_lock);
812 	seq = nametbl_find_seq(type);
813 	if (!seq) {
814 		seq = tipc_nameseq_create(type, &table.types[hash(type)]);
815 	}
816 	if (seq){
817 		spin_lock_bh(&seq->lock);
818 		dbg("tipc_nametbl_subscribe:found %p for {%u,%u,%u}\n",
819 		    seq, type, s->seq.lower, s->seq.upper);
820 		tipc_nameseq_subscribe(seq, s);
821 		spin_unlock_bh(&seq->lock);
822 	} else {
823 		warn("Failed to create subscription for {%u,%u,%u}\n",
824 		     s->seq.type, s->seq.lower, s->seq.upper);
825 	}
826 	write_unlock_bh(&tipc_nametbl_lock);
827 }
828 
829 /**
830  * tipc_nametbl_unsubscribe - remove a subscription object from name table
831  */
832 
833 void tipc_nametbl_unsubscribe(struct subscription *s)
834 {
835 	struct name_seq *seq;
836 
837 	write_lock_bh(&tipc_nametbl_lock);
838 	seq = nametbl_find_seq(s->seq.type);
839 	if (seq != NULL){
840 		spin_lock_bh(&seq->lock);
841 		list_del_init(&s->nameseq_list);
842 		spin_unlock_bh(&seq->lock);
843 		if ((seq->first_free == 0) && list_empty(&seq->subscriptions)) {
844 			hlist_del_init(&seq->ns_list);
845 			kfree(seq->sseqs);
846 			kfree(seq);
847 		}
848 	}
849 	write_unlock_bh(&tipc_nametbl_lock);
850 }
851 
852 
853 /**
854  * subseq_list: print specified sub-sequence contents into the given buffer
855  */
856 
857 static void subseq_list(struct sub_seq *sseq, struct print_buf *buf, u32 depth,
858 			u32 index)
859 {
860 	char portIdStr[27];
861 	char *scopeStr;
862 	struct publication *publ = sseq->zone_list;
863 
864 	tipc_printf(buf, "%-10u %-10u ", sseq->lower, sseq->upper);
865 
866 	if (depth == 2 || !publ) {
867 		tipc_printf(buf, "\n");
868 		return;
869 	}
870 
871 	do {
872 		sprintf (portIdStr, "<%u.%u.%u:%u>",
873 			 tipc_zone(publ->node), tipc_cluster(publ->node),
874 			 tipc_node(publ->node), publ->ref);
875 		tipc_printf(buf, "%-26s ", portIdStr);
876 		if (depth > 3) {
877 			if (publ->node != tipc_own_addr)
878 				scopeStr = "";
879 			else if (publ->scope == TIPC_NODE_SCOPE)
880 				scopeStr = "node";
881 			else if (publ->scope == TIPC_CLUSTER_SCOPE)
882 				scopeStr = "cluster";
883 			else
884 				scopeStr = "zone";
885 			tipc_printf(buf, "%-10u %s", publ->key, scopeStr);
886 		}
887 
888 		publ = publ->zone_list_next;
889 		if (publ == sseq->zone_list)
890 			break;
891 
892 		tipc_printf(buf, "\n%33s", " ");
893 	} while (1);
894 
895 	tipc_printf(buf, "\n");
896 }
897 
898 /**
899  * nameseq_list: print specified name sequence contents into the given buffer
900  */
901 
902 static void nameseq_list(struct name_seq *seq, struct print_buf *buf, u32 depth,
903 			 u32 type, u32 lowbound, u32 upbound, u32 index)
904 {
905 	struct sub_seq *sseq;
906 	char typearea[11];
907 
908 	sprintf(typearea, "%-10u", seq->type);
909 
910 	if (depth == 1) {
911 		tipc_printf(buf, "%s\n", typearea);
912 		return;
913 	}
914 
915 	for (sseq = seq->sseqs; sseq != &seq->sseqs[seq->first_free]; sseq++) {
916 		if ((lowbound <= sseq->upper) && (upbound >= sseq->lower)) {
917 			tipc_printf(buf, "%s ", typearea);
918 			subseq_list(sseq, buf, depth, index);
919 			sprintf(typearea, "%10s", " ");
920 		}
921 	}
922 }
923 
924 /**
925  * nametbl_header - print name table header into the given buffer
926  */
927 
928 static void nametbl_header(struct print_buf *buf, u32 depth)
929 {
930 	tipc_printf(buf, "Type       ");
931 
932 	if (depth > 1)
933 		tipc_printf(buf, "Lower      Upper      ");
934 	if (depth > 2)
935 		tipc_printf(buf, "Port Identity              ");
936 	if (depth > 3)
937 		tipc_printf(buf, "Publication");
938 
939 	tipc_printf(buf, "\n-----------");
940 
941 	if (depth > 1)
942 		tipc_printf(buf, "--------------------- ");
943 	if (depth > 2)
944 		tipc_printf(buf, "-------------------------- ");
945 	if (depth > 3)
946 		tipc_printf(buf, "------------------");
947 
948 	tipc_printf(buf, "\n");
949 }
950 
951 /**
952  * nametbl_list - print specified name table contents into the given buffer
953  */
954 
955 static void nametbl_list(struct print_buf *buf, u32 depth_info,
956 			 u32 type, u32 lowbound, u32 upbound)
957 {
958 	struct hlist_head *seq_head;
959 	struct hlist_node *seq_node;
960 	struct name_seq *seq;
961 	int all_types;
962 	u32 depth;
963 	u32 i;
964 
965 	all_types = (depth_info & TIPC_NTQ_ALLTYPES);
966 	depth = (depth_info & ~TIPC_NTQ_ALLTYPES);
967 
968 	if (depth == 0)
969 		return;
970 
971 	if (all_types) {
972 		/* display all entries in name table to specified depth */
973 		nametbl_header(buf, depth);
974 		lowbound = 0;
975 		upbound = ~0;
976 		for (i = 0; i < tipc_nametbl_size; i++) {
977 			seq_head = &table.types[i];
978 			hlist_for_each_entry(seq, seq_node, seq_head, ns_list) {
979 				nameseq_list(seq, buf, depth, seq->type,
980 					     lowbound, upbound, i);
981 			}
982 		}
983 	} else {
984 		/* display only the sequence that matches the specified type */
985 		if (upbound < lowbound) {
986 			tipc_printf(buf, "invalid name sequence specified\n");
987 			return;
988 		}
989 		nametbl_header(buf, depth);
990 		i = hash(type);
991 		seq_head = &table.types[i];
992 		hlist_for_each_entry(seq, seq_node, seq_head, ns_list) {
993 			if (seq->type == type) {
994 				nameseq_list(seq, buf, depth, type,
995 					     lowbound, upbound, i);
996 				break;
997 			}
998 		}
999 	}
1000 }
1001 
1002 #if 0
1003 void tipc_nametbl_print(struct print_buf *buf, const char *str)
1004 {
1005 	tipc_printf(buf, str);
1006 	read_lock_bh(&tipc_nametbl_lock);
1007 	nametbl_list(buf, 0, 0, 0, 0);
1008 	read_unlock_bh(&tipc_nametbl_lock);
1009 }
1010 #endif
1011 
1012 #define MAX_NAME_TBL_QUERY 32768
1013 
1014 struct sk_buff *tipc_nametbl_get(const void *req_tlv_area, int req_tlv_space)
1015 {
1016 	struct sk_buff *buf;
1017 	struct tipc_name_table_query *argv;
1018 	struct tlv_desc *rep_tlv;
1019 	struct print_buf b;
1020 	int str_len;
1021 
1022 	if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NAME_TBL_QUERY))
1023 		return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
1024 
1025 	buf = tipc_cfg_reply_alloc(TLV_SPACE(MAX_NAME_TBL_QUERY));
1026 	if (!buf)
1027 		return NULL;
1028 
1029 	rep_tlv = (struct tlv_desc *)buf->data;
1030 	tipc_printbuf_init(&b, TLV_DATA(rep_tlv), MAX_NAME_TBL_QUERY);
1031 	argv = (struct tipc_name_table_query *)TLV_DATA(req_tlv_area);
1032 	read_lock_bh(&tipc_nametbl_lock);
1033 	nametbl_list(&b, ntohl(argv->depth), ntohl(argv->type),
1034 		     ntohl(argv->lowbound), ntohl(argv->upbound));
1035 	read_unlock_bh(&tipc_nametbl_lock);
1036 	str_len = tipc_printbuf_validate(&b);
1037 
1038 	skb_put(buf, TLV_SPACE(str_len));
1039 	TLV_SET(rep_tlv, TIPC_TLV_ULTRA_STRING, NULL, str_len);
1040 
1041 	return buf;
1042 }
1043 
1044 #if 0
1045 void tipc_nametbl_dump(void)
1046 {
1047 	nametbl_list(TIPC_CONS, 0, 0, 0, 0);
1048 }
1049 #endif
1050 
1051 int tipc_nametbl_init(void)
1052 {
1053 	int array_size = sizeof(struct hlist_head) * tipc_nametbl_size;
1054 
1055 	table.types = kzalloc(array_size, GFP_ATOMIC);
1056 	if (!table.types)
1057 		return -ENOMEM;
1058 
1059 	write_lock_bh(&tipc_nametbl_lock);
1060 	table.local_publ_count = 0;
1061 	write_unlock_bh(&tipc_nametbl_lock);
1062 	return 0;
1063 }
1064 
1065 void tipc_nametbl_stop(void)
1066 {
1067 	u32 i;
1068 
1069 	if (!table.types)
1070 		return;
1071 
1072 	/* Verify name table is empty, then release it */
1073 
1074 	write_lock_bh(&tipc_nametbl_lock);
1075 	for (i = 0; i < tipc_nametbl_size; i++) {
1076 		if (!hlist_empty(&table.types[i]))
1077 			err("tipc_nametbl_stop(): hash chain %u is non-null\n", i);
1078 	}
1079 	kfree(table.types);
1080 	table.types = NULL;
1081 	write_unlock_bh(&tipc_nametbl_lock);
1082 }
1083 
1084