2 * net/tipc/bearer.c: TIPC bearer code
4 * Copyright (c) 1996-2006, Ericsson AB
5 * Copyright (c) 2004-2006, 2010-2011, Wind River Systems
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42 #define MAX_ADDR_STR 32
44 static struct media *media_list[MAX_MEDIA];
45 static u32 media_count;
47 struct tipc_bearer tipc_bearers[MAX_BEARERS];
49 static void bearer_disable(struct tipc_bearer *b_ptr);
52 * media_name_valid - validate media name
54 * Returns 1 if media name is valid, otherwise 0.
57 static int media_name_valid(const char *name)
62 if ((len + 1) > TIPC_MAX_MEDIA_NAME)
64 return strspn(name, tipc_alphabet) == len;
68 * media_find - locates specified media object by name
71 static struct media *media_find(const char *name)
75 for (i = 0; i < media_count; i++) {
76 if (!strcmp(media_list[i]->name, name))
83 * media_find_id - locates specified media object by type identifier
86 static struct media *media_find_id(u8 type)
90 for (i = 0; i < media_count; i++) {
91 if (media_list[i]->type_id == type)
98 * tipc_register_media - register a media type
100 * Bearers for this media type must be activated separately at a later stage.
103 int tipc_register_media(struct media *m_ptr)
107 write_lock_bh(&tipc_net_lock);
109 if (!media_name_valid(m_ptr->name))
111 if (m_ptr->bcast_addr.type != htonl(m_ptr->type_id))
113 if (m_ptr->priority > TIPC_MAX_LINK_PRI)
115 if ((m_ptr->tolerance < TIPC_MIN_LINK_TOL) ||
116 (m_ptr->tolerance > TIPC_MAX_LINK_TOL))
118 if (media_count >= MAX_MEDIA)
120 if (media_find(m_ptr->name) || media_find_id(m_ptr->type_id))
123 media_list[media_count] = m_ptr;
127 write_unlock_bh(&tipc_net_lock);
129 warn("Media <%s> registration error\n", m_ptr->name);
134 * tipc_media_addr_printf - record media address in print buffer
137 void tipc_media_addr_printf(struct print_buf *pb, struct tipc_media_addr *a)
139 char addr_str[MAX_ADDR_STR];
143 media_type = ntohl(a->type);
144 m_ptr = media_find_id(media_type);
146 if (m_ptr && !m_ptr->addr2str(a, addr_str, sizeof(addr_str)))
147 tipc_printf(pb, "%s(%s)", m_ptr->name, addr_str);
149 unchar *addr = (unchar *)&a->dev_addr;
152 tipc_printf(pb, "UNKNOWN(%u)", media_type);
153 for (i = 0; i < (sizeof(*a) - sizeof(a->type)); i++)
154 tipc_printf(pb, "-%02x", addr[i]);
159 * tipc_media_get_names - record names of registered media in buffer
162 struct sk_buff *tipc_media_get_names(void)
167 buf = tipc_cfg_reply_alloc(MAX_MEDIA * TLV_SPACE(TIPC_MAX_MEDIA_NAME));
171 read_lock_bh(&tipc_net_lock);
172 for (i = 0; i < media_count; i++) {
173 tipc_cfg_append_tlv(buf, TIPC_TLV_MEDIA_NAME,
175 strlen(media_list[i]->name) + 1);
177 read_unlock_bh(&tipc_net_lock);
182 * bearer_name_validate - validate & (optionally) deconstruct bearer name
183 * @name - ptr to bearer name string
184 * @name_parts - ptr to area for bearer name components (or NULL if not needed)
186 * Returns 1 if bearer name is valid, otherwise 0.
189 static int bearer_name_validate(const char *name,
190 struct bearer_name *name_parts)
192 char name_copy[TIPC_MAX_BEARER_NAME];
198 /* copy bearer name & ensure length is OK */
200 name_copy[TIPC_MAX_BEARER_NAME - 1] = 0;
201 /* need above in case non-Posix strncpy() doesn't pad with nulls */
202 strncpy(name_copy, name, TIPC_MAX_BEARER_NAME);
203 if (name_copy[TIPC_MAX_BEARER_NAME - 1] != 0)
206 /* ensure all component parts of bearer name are present */
208 media_name = name_copy;
209 if_name = strchr(media_name, ':');
213 media_len = if_name - media_name;
214 if_len = strlen(if_name) + 1;
216 /* validate component parts of bearer name */
218 if ((media_len <= 1) || (media_len > TIPC_MAX_MEDIA_NAME) ||
219 (if_len <= 1) || (if_len > TIPC_MAX_IF_NAME) ||
220 (strspn(media_name, tipc_alphabet) != (media_len - 1)) ||
221 (strspn(if_name, tipc_alphabet) != (if_len - 1)))
224 /* return bearer name components, if necessary */
227 strcpy(name_parts->media_name, media_name);
228 strcpy(name_parts->if_name, if_name);
234 * bearer_find - locates bearer object with matching bearer name
237 static struct tipc_bearer *bearer_find(const char *name)
239 struct tipc_bearer *b_ptr;
242 for (i = 0, b_ptr = tipc_bearers; i < MAX_BEARERS; i++, b_ptr++) {
243 if (b_ptr->active && (!strcmp(b_ptr->name, name)))
250 * tipc_bearer_find_interface - locates bearer object with matching interface name
253 struct tipc_bearer *tipc_bearer_find_interface(const char *if_name)
255 struct tipc_bearer *b_ptr;
259 for (i = 0, b_ptr = tipc_bearers; i < MAX_BEARERS; i++, b_ptr++) {
262 b_if_name = strchr(b_ptr->name, ':') + 1;
263 if (!strcmp(b_if_name, if_name))
270 * tipc_bearer_get_names - record names of bearers in buffer
273 struct sk_buff *tipc_bearer_get_names(void)
276 struct tipc_bearer *b_ptr;
279 buf = tipc_cfg_reply_alloc(MAX_BEARERS * TLV_SPACE(TIPC_MAX_BEARER_NAME));
283 read_lock_bh(&tipc_net_lock);
284 for (i = 0; i < media_count; i++) {
285 for (j = 0; j < MAX_BEARERS; j++) {
286 b_ptr = &tipc_bearers[j];
287 if (b_ptr->active && (b_ptr->media == media_list[i])) {
288 tipc_cfg_append_tlv(buf, TIPC_TLV_BEARER_NAME,
290 strlen(b_ptr->name) + 1);
294 read_unlock_bh(&tipc_net_lock);
298 void tipc_bearer_add_dest(struct tipc_bearer *b_ptr, u32 dest)
300 tipc_nmap_add(&b_ptr->nodes, dest);
301 tipc_bcbearer_sort();
302 tipc_disc_add_dest(b_ptr->link_req);
305 void tipc_bearer_remove_dest(struct tipc_bearer *b_ptr, u32 dest)
307 tipc_nmap_remove(&b_ptr->nodes, dest);
308 tipc_bcbearer_sort();
309 tipc_disc_remove_dest(b_ptr->link_req);
313 * bearer_push(): Resolve bearer congestion. Force the waiting
314 * links to push out their unsent packets, one packet per link
315 * per iteration, until all packets are gone or congestion reoccurs.
316 * 'tipc_net_lock' is read_locked when this function is called
317 * bearer.lock must be taken before calling
318 * Returns binary true(1) ore false(0)
320 static int bearer_push(struct tipc_bearer *b_ptr)
323 struct link *ln, *tln;
328 while (!list_empty(&b_ptr->cong_links) && (res != PUSH_FAILED)) {
329 list_for_each_entry_safe(ln, tln, &b_ptr->cong_links, link_list) {
330 res = tipc_link_push_packet(ln);
331 if (res == PUSH_FAILED)
333 if (res == PUSH_FINISHED)
334 list_move_tail(&ln->link_list, &b_ptr->links);
337 return list_empty(&b_ptr->cong_links);
340 void tipc_bearer_lock_push(struct tipc_bearer *b_ptr)
342 spin_lock_bh(&b_ptr->lock);
344 spin_unlock_bh(&b_ptr->lock);
349 * Interrupt enabling new requests after bearer congestion or blocking:
352 void tipc_continue(struct tipc_bearer *b_ptr)
354 spin_lock_bh(&b_ptr->lock);
355 if (!list_empty(&b_ptr->cong_links))
356 tipc_k_signal((Handler)tipc_bearer_lock_push, (unsigned long)b_ptr);
358 spin_unlock_bh(&b_ptr->lock);
362 * Schedule link for sending of messages after the bearer
363 * has been deblocked by 'continue()'. This method is called
364 * when somebody tries to send a message via this link while
365 * the bearer is congested. 'tipc_net_lock' is in read_lock here
366 * bearer.lock is busy
369 static void tipc_bearer_schedule_unlocked(struct tipc_bearer *b_ptr, struct link *l_ptr)
371 list_move_tail(&l_ptr->link_list, &b_ptr->cong_links);
375 * Schedule link for sending of messages after the bearer
376 * has been deblocked by 'continue()'. This method is called
377 * when somebody tries to send a message via this link while
378 * the bearer is congested. 'tipc_net_lock' is in read_lock here,
379 * bearer.lock is free
382 void tipc_bearer_schedule(struct tipc_bearer *b_ptr, struct link *l_ptr)
384 spin_lock_bh(&b_ptr->lock);
385 tipc_bearer_schedule_unlocked(b_ptr, l_ptr);
386 spin_unlock_bh(&b_ptr->lock);
391 * tipc_bearer_resolve_congestion(): Check if there is bearer congestion,
392 * and if there is, try to resolve it before returning.
393 * 'tipc_net_lock' is read_locked when this function is called
395 int tipc_bearer_resolve_congestion(struct tipc_bearer *b_ptr, struct link *l_ptr)
399 if (list_empty(&b_ptr->cong_links))
401 spin_lock_bh(&b_ptr->lock);
402 if (!bearer_push(b_ptr)) {
403 tipc_bearer_schedule_unlocked(b_ptr, l_ptr);
406 spin_unlock_bh(&b_ptr->lock);
411 * tipc_bearer_congested - determines if bearer is currently congested
414 int tipc_bearer_congested(struct tipc_bearer *b_ptr, struct link *l_ptr)
416 if (unlikely(b_ptr->blocked))
418 if (likely(list_empty(&b_ptr->cong_links)))
420 return !tipc_bearer_resolve_congestion(b_ptr, l_ptr);
424 * tipc_enable_bearer - enable bearer with the given name
427 int tipc_enable_bearer(const char *name, u32 disc_domain, u32 priority)
429 struct tipc_bearer *b_ptr;
431 struct bearer_name b_name;
432 char addr_string[16];
438 if (tipc_mode != TIPC_NET_MODE) {
439 warn("Bearer <%s> rejected, not supported in standalone mode\n",
443 if (!bearer_name_validate(name, &b_name)) {
444 warn("Bearer <%s> rejected, illegal name\n", name);
447 if (tipc_addr_domain_valid(disc_domain) &&
448 (disc_domain != tipc_own_addr)) {
449 if (tipc_in_scope(disc_domain, tipc_own_addr)) {
450 disc_domain = tipc_own_addr & TIPC_CLUSTER_MASK;
451 res = 0; /* accept any node in own cluster */
452 } else if (in_own_cluster(disc_domain))
453 res = 0; /* accept specified node in own cluster */
456 warn("Bearer <%s> rejected, illegal discovery domain\n", name);
459 if ((priority < TIPC_MIN_LINK_PRI ||
460 priority > TIPC_MAX_LINK_PRI) &&
461 (priority != TIPC_MEDIA_LINK_PRI)) {
462 warn("Bearer <%s> rejected, illegal priority\n", name);
466 write_lock_bh(&tipc_net_lock);
468 m_ptr = media_find(b_name.media_name);
470 warn("Bearer <%s> rejected, media <%s> not registered\n", name,
475 if (priority == TIPC_MEDIA_LINK_PRI)
476 priority = m_ptr->priority;
479 bearer_id = MAX_BEARERS;
481 for (i = MAX_BEARERS; i-- != 0; ) {
482 if (!tipc_bearers[i].active) {
486 if (!strcmp(name, tipc_bearers[i].name)) {
487 warn("Bearer <%s> rejected, already enabled\n", name);
490 if ((tipc_bearers[i].priority == priority) &&
491 (++with_this_prio > 2)) {
492 if (priority-- == 0) {
493 warn("Bearer <%s> rejected, duplicate priority\n",
497 warn("Bearer <%s> priority adjustment required %u->%u\n",
498 name, priority + 1, priority);
502 if (bearer_id >= MAX_BEARERS) {
503 warn("Bearer <%s> rejected, bearer limit reached (%u)\n",
508 b_ptr = &tipc_bearers[bearer_id];
509 strcpy(b_ptr->name, name);
510 res = m_ptr->enable_bearer(b_ptr);
512 warn("Bearer <%s> rejected, enable failure (%d)\n", name, -res);
516 b_ptr->identity = bearer_id;
517 b_ptr->media = m_ptr;
518 b_ptr->net_plane = bearer_id + 'A';
520 b_ptr->priority = priority;
521 INIT_LIST_HEAD(&b_ptr->cong_links);
522 INIT_LIST_HEAD(&b_ptr->links);
523 spin_lock_init(&b_ptr->lock);
525 res = tipc_disc_create(b_ptr, &m_ptr->bcast_addr, disc_domain);
527 bearer_disable(b_ptr);
528 warn("Bearer <%s> rejected, discovery object creation failed\n",
532 info("Enabled bearer <%s>, discovery domain %s, priority %u\n",
533 name, tipc_addr_string_fill(addr_string, disc_domain), priority);
535 write_unlock_bh(&tipc_net_lock);
540 * tipc_block_bearer(): Block the bearer with the given name,
541 * and reset all its links
544 int tipc_block_bearer(const char *name)
546 struct tipc_bearer *b_ptr = NULL;
548 struct link *temp_l_ptr;
550 read_lock_bh(&tipc_net_lock);
551 b_ptr = bearer_find(name);
553 warn("Attempt to block unknown bearer <%s>\n", name);
554 read_unlock_bh(&tipc_net_lock);
558 info("Blocking bearer <%s>\n", name);
559 spin_lock_bh(&b_ptr->lock);
561 list_splice_init(&b_ptr->cong_links, &b_ptr->links);
562 list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) {
563 struct tipc_node *n_ptr = l_ptr->owner;
565 spin_lock_bh(&n_ptr->lock);
566 tipc_link_reset(l_ptr);
567 spin_unlock_bh(&n_ptr->lock);
569 spin_unlock_bh(&b_ptr->lock);
570 read_unlock_bh(&tipc_net_lock);
577 * Note: This routine assumes caller holds tipc_net_lock.
580 static void bearer_disable(struct tipc_bearer *b_ptr)
583 struct link *temp_l_ptr;
585 info("Disabling bearer <%s>\n", b_ptr->name);
586 spin_lock_bh(&b_ptr->lock);
588 b_ptr->media->disable_bearer(b_ptr);
589 list_splice_init(&b_ptr->cong_links, &b_ptr->links);
590 list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) {
591 tipc_link_delete(l_ptr);
594 tipc_disc_delete(b_ptr->link_req);
595 spin_unlock_bh(&b_ptr->lock);
596 memset(b_ptr, 0, sizeof(struct tipc_bearer));
599 int tipc_disable_bearer(const char *name)
601 struct tipc_bearer *b_ptr;
604 write_lock_bh(&tipc_net_lock);
605 b_ptr = bearer_find(name);
607 warn("Attempt to disable unknown bearer <%s>\n", name);
610 bearer_disable(b_ptr);
613 write_unlock_bh(&tipc_net_lock);
619 void tipc_bearer_stop(void)
623 for (i = 0; i < MAX_BEARERS; i++) {
624 if (tipc_bearers[i].active)
625 bearer_disable(&tipc_bearers[i]);