2 * net/tipc/bearer.c: TIPC bearer code
4 * Copyright (c) 1996-2006, Ericsson AB
5 * Copyright (c) 2004-2005, Wind River Systems
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21 * GNU General Public License ("GPL") version 2 as published by the Free
22 * Software Foundation.
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46 #define MAX_ADDR_STR 32
48 static struct media *media_list = NULL;
49 static u32 media_count = 0;
51 struct bearer *tipc_bearers = NULL;
54 * media_name_valid - validate media name
56 * Returns 1 if media name is valid, otherwise 0.
59 static int media_name_valid(const char *name)
64 if ((len + 1) > TIPC_MAX_MEDIA_NAME)
66 return (strspn(name, tipc_alphabet) == len);
70 * media_find - locates specified media object by name
73 static struct media *media_find(const char *name)
78 for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
79 if (!strcmp(m_ptr->name, name))
86 * tipc_register_media - register a media type
88 * Bearers for this media type must be activated separately at a later stage.
91 int tipc_register_media(u32 media_type,
93 int (*enable)(struct tipc_bearer *),
94 void (*disable)(struct tipc_bearer *),
95 int (*send_msg)(struct sk_buff *,
97 struct tipc_media_addr *),
98 char *(*addr2str)(struct tipc_media_addr *a,
99 char *str_buf, int str_size),
100 struct tipc_media_addr *bcast_addr,
101 const u32 bearer_priority,
102 const u32 link_tolerance, /* [ms] */
103 const u32 send_window_limit)
110 write_lock_bh(&tipc_net_lock);
114 if (!media_name_valid(name)) {
115 warn("Media registration error: illegal name <%s>\n", name);
119 warn("Media registration error: no broadcast address supplied\n");
122 if ((bearer_priority < TIPC_MIN_LINK_PRI) &&
123 (bearer_priority > TIPC_MAX_LINK_PRI)) {
124 warn("Media registration error: priority %u\n", bearer_priority);
127 if ((link_tolerance < TIPC_MIN_LINK_TOL) ||
128 (link_tolerance > TIPC_MAX_LINK_TOL)) {
129 warn("Media registration error: tolerance %u\n", link_tolerance);
133 media_id = media_count++;
134 if (media_id >= MAX_MEDIA) {
135 warn("Attempt to register more than %u media\n", MAX_MEDIA);
139 for (i = 0; i < media_id; i++) {
140 if (media_list[i].type_id == media_type) {
141 warn("Attempt to register second media with type %u\n",
146 if (!strcmp(name, media_list[i].name)) {
147 warn("Attempt to re-register media name <%s>\n", name);
153 m_ptr = &media_list[media_id];
154 m_ptr->type_id = media_type;
155 m_ptr->send_msg = send_msg;
156 m_ptr->enable_bearer = enable;
157 m_ptr->disable_bearer = disable;
158 m_ptr->addr2str = addr2str;
159 memcpy(&m_ptr->bcast_addr, bcast_addr, sizeof(*bcast_addr));
161 strcpy(m_ptr->name, name);
162 m_ptr->priority = bearer_priority;
163 m_ptr->tolerance = link_tolerance;
164 m_ptr->window = send_window_limit;
165 dbg("Media <%s> registered\n", name);
168 write_unlock_bh(&tipc_net_lock);
173 * tipc_media_addr_printf - record media address in print buffer
176 void tipc_media_addr_printf(struct print_buf *pb, struct tipc_media_addr *a)
182 media_type = ntohl(a->type);
183 for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
184 if (m_ptr->type_id == media_type)
188 if ((i < media_count) && (m_ptr->addr2str != NULL)) {
189 char addr_str[MAX_ADDR_STR];
191 tipc_printf(pb, "%s(%s) ", m_ptr->name,
192 m_ptr->addr2str(a, addr_str, sizeof(addr_str)));
194 unchar *addr = (unchar *)&a->dev_addr;
196 tipc_printf(pb, "UNKNOWN(%u):", media_type);
197 for (i = 0; i < (sizeof(*a) - sizeof(a->type)); i++) {
198 tipc_printf(pb, "%02x ", addr[i]);
204 * tipc_media_get_names - record names of registered media in buffer
207 struct sk_buff *tipc_media_get_names(void)
213 buf = tipc_cfg_reply_alloc(MAX_MEDIA * TLV_SPACE(TIPC_MAX_MEDIA_NAME));
217 read_lock_bh(&tipc_net_lock);
218 for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
219 tipc_cfg_append_tlv(buf, TIPC_TLV_MEDIA_NAME, m_ptr->name,
220 strlen(m_ptr->name) + 1);
222 read_unlock_bh(&tipc_net_lock);
227 * bearer_name_validate - validate & (optionally) deconstruct bearer name
228 * @name - ptr to bearer name string
229 * @name_parts - ptr to area for bearer name components (or NULL if not needed)
231 * Returns 1 if bearer name is valid, otherwise 0.
234 static int bearer_name_validate(const char *name,
235 struct bearer_name *name_parts)
237 char name_copy[TIPC_MAX_BEARER_NAME];
243 /* copy bearer name & ensure length is OK */
245 name_copy[TIPC_MAX_BEARER_NAME - 1] = 0;
246 /* need above in case non-Posix strncpy() doesn't pad with nulls */
247 strncpy(name_copy, name, TIPC_MAX_BEARER_NAME);
248 if (name_copy[TIPC_MAX_BEARER_NAME - 1] != 0)
251 /* ensure all component parts of bearer name are present */
253 media_name = name_copy;
254 if ((if_name = strchr(media_name, ':')) == NULL)
257 media_len = if_name - media_name;
258 if_len = strlen(if_name) + 1;
260 /* validate component parts of bearer name */
262 if ((media_len <= 1) || (media_len > TIPC_MAX_MEDIA_NAME) ||
263 (if_len <= 1) || (if_len > TIPC_MAX_IF_NAME) ||
264 (strspn(media_name, tipc_alphabet) != (media_len - 1)) ||
265 (strspn(if_name, tipc_alphabet) != (if_len - 1)))
268 /* return bearer name components, if necessary */
271 strcpy(name_parts->media_name, media_name);
272 strcpy(name_parts->if_name, if_name);
278 * bearer_find - locates bearer object with matching bearer name
281 static struct bearer *bearer_find(const char *name)
283 struct bearer *b_ptr;
286 for (i = 0, b_ptr = tipc_bearers; i < MAX_BEARERS; i++, b_ptr++) {
287 if (b_ptr->active && (!strcmp(b_ptr->publ.name, name)))
294 * tipc_bearer_find_interface - locates bearer object with matching interface name
297 struct bearer *tipc_bearer_find_interface(const char *if_name)
299 struct bearer *b_ptr;
303 for (i = 0, b_ptr = tipc_bearers; i < MAX_BEARERS; i++, b_ptr++) {
306 b_if_name = strchr(b_ptr->publ.name, ':') + 1;
307 if (!strcmp(b_if_name, if_name))
314 * tipc_bearer_get_names - record names of bearers in buffer
317 struct sk_buff *tipc_bearer_get_names(void)
321 struct bearer *b_ptr;
324 buf = tipc_cfg_reply_alloc(MAX_BEARERS * TLV_SPACE(TIPC_MAX_BEARER_NAME));
328 read_lock_bh(&tipc_net_lock);
329 for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
330 for (j = 0; j < MAX_BEARERS; j++) {
331 b_ptr = &tipc_bearers[j];
332 if (b_ptr->active && (b_ptr->media == m_ptr)) {
333 tipc_cfg_append_tlv(buf, TIPC_TLV_BEARER_NAME,
335 strlen(b_ptr->publ.name) + 1);
339 read_unlock_bh(&tipc_net_lock);
343 void tipc_bearer_add_dest(struct bearer *b_ptr, u32 dest)
345 tipc_nmap_add(&b_ptr->nodes, dest);
346 tipc_disc_update_link_req(b_ptr->link_req);
347 tipc_bcbearer_sort();
350 void tipc_bearer_remove_dest(struct bearer *b_ptr, u32 dest)
352 tipc_nmap_remove(&b_ptr->nodes, dest);
353 tipc_disc_update_link_req(b_ptr->link_req);
354 tipc_bcbearer_sort();
358 * bearer_push(): Resolve bearer congestion. Force the waiting
359 * links to push out their unsent packets, one packet per link
360 * per iteration, until all packets are gone or congestion reoccurs.
361 * 'tipc_net_lock' is read_locked when this function is called
362 * bearer.lock must be taken before calling
363 * Returns binary true(1) ore false(0)
365 static int bearer_push(struct bearer *b_ptr)
368 struct link *ln, *tln;
370 if (b_ptr->publ.blocked)
373 while (!list_empty(&b_ptr->cong_links) && (res != PUSH_FAILED)) {
374 list_for_each_entry_safe(ln, tln, &b_ptr->cong_links, link_list) {
375 res = tipc_link_push_packet(ln);
376 if (res == PUSH_FAILED)
378 if (res == PUSH_FINISHED)
379 list_move_tail(&ln->link_list, &b_ptr->links);
382 return list_empty(&b_ptr->cong_links);
385 void tipc_bearer_lock_push(struct bearer *b_ptr)
389 spin_lock_bh(&b_ptr->publ.lock);
390 res = bearer_push(b_ptr);
391 spin_unlock_bh(&b_ptr->publ.lock);
393 tipc_bcbearer_push();
398 * Interrupt enabling new requests after bearer congestion or blocking:
401 void tipc_continue(struct tipc_bearer *tb_ptr)
403 struct bearer *b_ptr = (struct bearer *)tb_ptr;
405 spin_lock_bh(&b_ptr->publ.lock);
406 b_ptr->continue_count++;
407 if (!list_empty(&b_ptr->cong_links))
408 tipc_k_signal((Handler)tipc_bearer_lock_push, (unsigned long)b_ptr);
409 b_ptr->publ.blocked = 0;
410 spin_unlock_bh(&b_ptr->publ.lock);
414 * Schedule link for sending of messages after the bearer
415 * has been deblocked by 'continue()'. This method is called
416 * when somebody tries to send a message via this link while
417 * the bearer is congested. 'tipc_net_lock' is in read_lock here
418 * bearer.lock is busy
421 static void tipc_bearer_schedule_unlocked(struct bearer *b_ptr, struct link *l_ptr)
423 list_move_tail(&l_ptr->link_list, &b_ptr->cong_links);
427 * Schedule link for sending of messages after the bearer
428 * has been deblocked by 'continue()'. This method is called
429 * when somebody tries to send a message via this link while
430 * the bearer is congested. 'tipc_net_lock' is in read_lock here,
431 * bearer.lock is free
434 void tipc_bearer_schedule(struct bearer *b_ptr, struct link *l_ptr)
436 spin_lock_bh(&b_ptr->publ.lock);
437 tipc_bearer_schedule_unlocked(b_ptr, l_ptr);
438 spin_unlock_bh(&b_ptr->publ.lock);
443 * tipc_bearer_resolve_congestion(): Check if there is bearer congestion,
444 * and if there is, try to resolve it before returning.
445 * 'tipc_net_lock' is read_locked when this function is called
447 int tipc_bearer_resolve_congestion(struct bearer *b_ptr, struct link *l_ptr)
451 if (list_empty(&b_ptr->cong_links))
453 spin_lock_bh(&b_ptr->publ.lock);
454 if (!bearer_push(b_ptr)) {
455 tipc_bearer_schedule_unlocked(b_ptr, l_ptr);
458 spin_unlock_bh(&b_ptr->publ.lock);
464 * tipc_enable_bearer - enable bearer with the given name
467 int tipc_enable_bearer(const char *name, u32 bcast_scope, u32 priority)
469 struct bearer *b_ptr;
471 struct bearer_name b_name;
472 char addr_string[16];
478 if (tipc_mode != TIPC_NET_MODE)
481 if (!bearer_name_validate(name, &b_name) ||
482 !tipc_addr_domain_valid(bcast_scope) ||
483 !in_scope(bcast_scope, tipc_own_addr))
486 if ((priority < TIPC_MIN_LINK_PRI ||
487 priority > TIPC_MAX_LINK_PRI) &&
488 (priority != TIPC_MEDIA_LINK_PRI))
491 write_lock_bh(&tipc_net_lock);
495 m_ptr = media_find(b_name.media_name);
497 warn("No media <%s>\n", b_name.media_name);
501 if (priority == TIPC_MEDIA_LINK_PRI)
502 priority = m_ptr->priority;
505 bearer_id = MAX_BEARERS;
507 for (i = MAX_BEARERS; i-- != 0; ) {
508 if (!tipc_bearers[i].active) {
512 if (!strcmp(name, tipc_bearers[i].publ.name)) {
513 warn("Bearer <%s> already enabled\n", name);
516 if ((tipc_bearers[i].priority == priority) &&
517 (++with_this_prio > 2)) {
518 if (priority-- == 0) {
519 warn("Third bearer <%s> with priority %u, unable to lower to %u\n",
520 name, priority + 1, priority);
523 warn("Third bearer <%s> with priority %u, lowering to %u\n",
524 name, priority + 1, priority);
528 if (bearer_id >= MAX_BEARERS) {
529 warn("Attempt to enable more than %d bearers\n", MAX_BEARERS);
533 b_ptr = &tipc_bearers[bearer_id];
534 memset(b_ptr, 0, sizeof(struct bearer));
536 strcpy(b_ptr->publ.name, name);
537 res = m_ptr->enable_bearer(&b_ptr->publ);
539 warn("Failed to enable bearer <%s>\n", name);
543 b_ptr->identity = bearer_id;
544 b_ptr->media = m_ptr;
545 b_ptr->net_plane = bearer_id + 'A';
547 b_ptr->detect_scope = bcast_scope;
548 b_ptr->priority = priority;
549 INIT_LIST_HEAD(&b_ptr->cong_links);
550 INIT_LIST_HEAD(&b_ptr->links);
552 b_ptr->link_req = tipc_disc_init_link_req(b_ptr, &m_ptr->bcast_addr,
555 b_ptr->publ.lock = SPIN_LOCK_UNLOCKED;
556 write_unlock_bh(&tipc_net_lock);
557 info("Enabled bearer <%s>, discovery domain %s, priority %u\n",
558 name, addr_string_fill(addr_string, bcast_scope), priority);
561 write_unlock_bh(&tipc_net_lock);
566 * tipc_block_bearer(): Block the bearer with the given name,
567 * and reset all its links
570 int tipc_block_bearer(const char *name)
572 struct bearer *b_ptr = NULL;
574 struct link *temp_l_ptr;
576 if (tipc_mode != TIPC_NET_MODE)
579 read_lock_bh(&tipc_net_lock);
580 b_ptr = bearer_find(name);
582 warn("Attempt to block unknown bearer <%s>\n", name);
583 read_unlock_bh(&tipc_net_lock);
587 spin_lock_bh(&b_ptr->publ.lock);
588 b_ptr->publ.blocked = 1;
589 list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) {
590 struct node *n_ptr = l_ptr->owner;
592 spin_lock_bh(&n_ptr->lock);
593 tipc_link_reset(l_ptr);
594 spin_unlock_bh(&n_ptr->lock);
596 spin_unlock_bh(&b_ptr->publ.lock);
597 read_unlock_bh(&tipc_net_lock);
598 info("Blocked bearer <%s>\n", name);
605 * Note: This routine assumes caller holds tipc_net_lock.
608 static int bearer_disable(const char *name)
610 struct bearer *b_ptr;
612 struct link *temp_l_ptr;
614 if (tipc_mode != TIPC_NET_MODE)
617 b_ptr = bearer_find(name);
619 warn("Attempt to disable unknown bearer <%s>\n", name);
623 tipc_disc_stop_link_req(b_ptr->link_req);
624 spin_lock_bh(&b_ptr->publ.lock);
625 b_ptr->link_req = NULL;
626 b_ptr->publ.blocked = 1;
627 if (b_ptr->media->disable_bearer) {
628 spin_unlock_bh(&b_ptr->publ.lock);
629 write_unlock_bh(&tipc_net_lock);
630 b_ptr->media->disable_bearer(&b_ptr->publ);
631 write_lock_bh(&tipc_net_lock);
632 spin_lock_bh(&b_ptr->publ.lock);
634 list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) {
635 tipc_link_delete(l_ptr);
637 spin_unlock_bh(&b_ptr->publ.lock);
638 info("Disabled bearer <%s>\n", name);
639 memset(b_ptr, 0, sizeof(struct bearer));
643 int tipc_disable_bearer(const char *name)
647 write_lock_bh(&tipc_net_lock);
648 res = bearer_disable(name);
649 write_unlock_bh(&tipc_net_lock);
655 int tipc_bearer_init(void)
659 write_lock_bh(&tipc_net_lock);
660 tipc_bearers = kmalloc(MAX_BEARERS * sizeof(struct bearer), GFP_ATOMIC);
661 media_list = kmalloc(MAX_MEDIA * sizeof(struct media), GFP_ATOMIC);
662 if (tipc_bearers && media_list) {
663 memset(tipc_bearers, 0, MAX_BEARERS * sizeof(struct bearer));
664 memset(media_list, 0, MAX_MEDIA * sizeof(struct media));
673 write_unlock_bh(&tipc_net_lock);
677 void tipc_bearer_stop(void)
684 for (i = 0; i < MAX_BEARERS; i++) {
685 if (tipc_bearers[i].active)
686 tipc_bearers[i].publ.blocked = 1;
688 for (i = 0; i < MAX_BEARERS; i++) {
689 if (tipc_bearers[i].active)
690 bearer_disable(tipc_bearers[i].publ.name);