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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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
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46 #define MAX_ADDR_STR 32
48 static struct media *media_list = 0;
49 static u32 media_count = 0;
51 struct bearer *bearers = 0;
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(&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_NUM_LINK_PRI) {
123 warn("Media registration error: priority %u\n", bearer_priority);
126 if ((link_tolerance < TIPC_MIN_LINK_TOL) ||
127 (link_tolerance > TIPC_MAX_LINK_TOL)) {
128 warn("Media registration error: tolerance %u\n", link_tolerance);
132 media_id = media_count++;
133 if (media_id >= MAX_MEDIA) {
134 warn("Attempt to register more than %u media\n", MAX_MEDIA);
138 for (i = 0; i < media_id; i++) {
139 if (media_list[i].type_id == media_type) {
140 warn("Attempt to register second media with type %u\n",
145 if (!strcmp(name, media_list[i].name)) {
146 warn("Attempt to re-register media name <%s>\n", name);
152 m_ptr = &media_list[media_id];
153 m_ptr->type_id = media_type;
154 m_ptr->send_msg = send_msg;
155 m_ptr->enable_bearer = enable;
156 m_ptr->disable_bearer = disable;
157 m_ptr->addr2str = addr2str;
158 memcpy(&m_ptr->bcast_addr, bcast_addr, sizeof(*bcast_addr));
160 strcpy(m_ptr->name, name);
161 m_ptr->priority = bearer_priority;
162 m_ptr->tolerance = link_tolerance;
163 m_ptr->window = send_window_limit;
164 dbg("Media <%s> registered\n", name);
167 write_unlock_bh(&net_lock);
172 * media_addr_printf - record media address in print buffer
175 void media_addr_printf(struct print_buf *pb, struct tipc_media_addr *a)
181 media_type = ntohl(a->type);
182 for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
183 if (m_ptr->type_id == media_type)
187 if ((i < media_count) && (m_ptr->addr2str != NULL)) {
188 char addr_str[MAX_ADDR_STR];
190 tipc_printf(pb, "%s(%s) ", m_ptr->name,
191 m_ptr->addr2str(a, addr_str, sizeof(addr_str)));
193 unchar *addr = (unchar *)&a->dev_addr;
195 tipc_printf(pb, "UNKNOWN(%u):", media_type);
196 for (i = 0; i < (sizeof(*a) - sizeof(a->type)); i++) {
197 tipc_printf(pb, "%02x ", addr[i]);
203 * media_get_names - record names of registered media in buffer
206 struct sk_buff *media_get_names(void)
212 buf = cfg_reply_alloc(MAX_MEDIA * TLV_SPACE(TIPC_MAX_MEDIA_NAME));
216 read_lock_bh(&net_lock);
217 for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
218 cfg_append_tlv(buf, TIPC_TLV_MEDIA_NAME, m_ptr->name,
219 strlen(m_ptr->name) + 1);
221 read_unlock_bh(&net_lock);
226 * bearer_name_validate - validate & (optionally) deconstruct bearer name
227 * @name - ptr to bearer name string
228 * @name_parts - ptr to area for bearer name components (or NULL if not needed)
230 * Returns 1 if bearer name is valid, otherwise 0.
233 static int bearer_name_validate(const char *name,
234 struct bearer_name *name_parts)
236 char name_copy[TIPC_MAX_BEARER_NAME];
242 /* copy bearer name & ensure length is OK */
244 name_copy[TIPC_MAX_BEARER_NAME - 1] = 0;
245 /* need above in case non-Posix strncpy() doesn't pad with nulls */
246 strncpy(name_copy, name, TIPC_MAX_BEARER_NAME);
247 if (name_copy[TIPC_MAX_BEARER_NAME - 1] != 0)
250 /* ensure all component parts of bearer name are present */
252 media_name = name_copy;
253 if ((if_name = strchr(media_name, ':')) == NULL)
256 media_len = if_name - media_name;
257 if_len = strlen(if_name) + 1;
259 /* validate component parts of bearer name */
261 if ((media_len <= 1) || (media_len > TIPC_MAX_MEDIA_NAME) ||
262 (if_len <= 1) || (if_len > TIPC_MAX_IF_NAME) ||
263 (strspn(media_name, tipc_alphabet) != (media_len - 1)) ||
264 (strspn(if_name, tipc_alphabet) != (if_len - 1)))
267 /* return bearer name components, if necessary */
270 strcpy(name_parts->media_name, media_name);
271 strcpy(name_parts->if_name, if_name);
277 * bearer_find - locates bearer object with matching bearer name
280 static struct bearer *bearer_find(const char *name)
282 struct bearer *b_ptr;
285 for (i = 0, b_ptr = bearers; i < MAX_BEARERS; i++, b_ptr++) {
286 if (b_ptr->active && (!strcmp(b_ptr->publ.name, name)))
293 * bearer_find - locates bearer object with matching interface name
296 struct bearer *bearer_find_interface(const char *if_name)
298 struct bearer *b_ptr;
302 for (i = 0, b_ptr = bearers; i < MAX_BEARERS; i++, b_ptr++) {
305 b_if_name = strchr(b_ptr->publ.name, ':') + 1;
306 if (!strcmp(b_if_name, if_name))
313 * bearer_get_names - record names of bearers in buffer
316 struct sk_buff *bearer_get_names(void)
320 struct bearer *b_ptr;
323 buf = cfg_reply_alloc(MAX_BEARERS * TLV_SPACE(TIPC_MAX_BEARER_NAME));
327 read_lock_bh(&net_lock);
328 for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
329 for (j = 0; j < MAX_BEARERS; j++) {
331 if (b_ptr->active && (b_ptr->media == m_ptr)) {
332 cfg_append_tlv(buf, TIPC_TLV_BEARER_NAME,
334 strlen(b_ptr->publ.name) + 1);
338 read_unlock_bh(&net_lock);
342 void bearer_add_dest(struct bearer *b_ptr, u32 dest)
344 nmap_add(&b_ptr->nodes, dest);
345 disc_update_link_req(b_ptr->link_req);
349 void bearer_remove_dest(struct bearer *b_ptr, u32 dest)
351 nmap_remove(&b_ptr->nodes, dest);
352 disc_update_link_req(b_ptr->link_req);
357 * bearer_push(): Resolve bearer congestion. Force the waiting
358 * links to push out their unsent packets, one packet per link
359 * per iteration, until all packets are gone or congestion reoccurs.
360 * 'net_lock' is read_locked when this function is called
361 * bearer.lock must be taken before calling
362 * Returns binary true(1) ore false(0)
364 static int bearer_push(struct bearer *b_ptr)
367 struct link *ln, *tln;
369 if (b_ptr->publ.blocked)
372 while (!list_empty(&b_ptr->cong_links) && (res != PUSH_FAILED)) {
373 list_for_each_entry_safe(ln, tln, &b_ptr->cong_links, link_list) {
374 res = link_push_packet(ln);
375 if (res == PUSH_FAILED)
377 if (res == PUSH_FINISHED)
378 list_move_tail(&ln->link_list, &b_ptr->links);
381 return list_empty(&b_ptr->cong_links);
384 void bearer_lock_push(struct bearer *b_ptr)
388 spin_lock_bh(&b_ptr->publ.lock);
389 res = bearer_push(b_ptr);
390 spin_unlock_bh(&b_ptr->publ.lock);
397 * Interrupt enabling new requests after bearer congestion or blocking:
400 void tipc_continue(struct tipc_bearer *tb_ptr)
402 struct bearer *b_ptr = (struct bearer *)tb_ptr;
404 spin_lock_bh(&b_ptr->publ.lock);
405 b_ptr->continue_count++;
406 if (!list_empty(&b_ptr->cong_links))
407 k_signal((Handler)bearer_lock_push, (unsigned long)b_ptr);
408 b_ptr->publ.blocked = 0;
409 spin_unlock_bh(&b_ptr->publ.lock);
413 * Schedule link for sending of messages after the bearer
414 * has been deblocked by 'continue()'. This method is called
415 * when somebody tries to send a message via this link while
416 * the bearer is congested. 'net_lock' is in read_lock here
417 * bearer.lock is busy
420 static void bearer_schedule_unlocked(struct bearer *b_ptr, struct link *l_ptr)
422 list_move_tail(&l_ptr->link_list, &b_ptr->cong_links);
426 * Schedule link for sending of messages after the bearer
427 * has been deblocked by 'continue()'. This method is called
428 * when somebody tries to send a message via this link while
429 * the bearer is congested. 'net_lock' is in read_lock here,
430 * bearer.lock is free
433 void bearer_schedule(struct bearer *b_ptr, struct link *l_ptr)
435 spin_lock_bh(&b_ptr->publ.lock);
436 bearer_schedule_unlocked(b_ptr, l_ptr);
437 spin_unlock_bh(&b_ptr->publ.lock);
442 * bearer_resolve_congestion(): Check if there is bearer congestion,
443 * and if there is, try to resolve it before returning.
444 * 'net_lock' is read_locked when this function is called
446 int bearer_resolve_congestion(struct bearer *b_ptr, struct link *l_ptr)
450 if (list_empty(&b_ptr->cong_links))
452 spin_lock_bh(&b_ptr->publ.lock);
453 if (!bearer_push(b_ptr)) {
454 bearer_schedule_unlocked(b_ptr, l_ptr);
457 spin_unlock_bh(&b_ptr->publ.lock);
463 * tipc_enable_bearer - enable bearer with the given name
466 int tipc_enable_bearer(const char *name, u32 bcast_scope, u32 priority)
468 struct bearer *b_ptr;
470 struct bearer_name b_name;
471 char addr_string[16];
477 if (tipc_mode != TIPC_NET_MODE)
479 if (!bearer_name_validate(name, &b_name) ||
480 !addr_domain_valid(bcast_scope) ||
481 !in_scope(bcast_scope, tipc_own_addr) ||
482 (priority > TIPC_NUM_LINK_PRI))
485 write_lock_bh(&net_lock);
489 m_ptr = media_find(b_name.media_name);
491 warn("No media <%s>\n", b_name.media_name);
494 if (priority == TIPC_NUM_LINK_PRI)
495 priority = m_ptr->priority;
498 bearer_id = MAX_BEARERS;
500 for (i = MAX_BEARERS; i-- != 0; ) {
501 if (!bearers[i].active) {
505 if (!strcmp(name, bearers[i].publ.name)) {
506 warn("Bearer <%s> already enabled\n", name);
509 if ((bearers[i].priority == priority) &&
510 (++with_this_prio > 2)) {
511 if (priority-- == 0) {
512 warn("Third bearer <%s> with priority %u, unable to lower to %u\n",
513 name, priority + 1, priority);
516 warn("Third bearer <%s> with priority %u, lowering to %u\n",
517 name, priority + 1, priority);
521 if (bearer_id >= MAX_BEARERS) {
522 warn("Attempt to enable more than %d bearers\n", MAX_BEARERS);
526 b_ptr = &bearers[bearer_id];
527 memset(b_ptr, 0, sizeof(struct bearer));
529 strcpy(b_ptr->publ.name, name);
530 res = m_ptr->enable_bearer(&b_ptr->publ);
532 warn("Failed to enable bearer <%s>\n", name);
536 b_ptr->identity = bearer_id;
537 b_ptr->media = m_ptr;
538 b_ptr->net_plane = bearer_id + 'A';
540 b_ptr->detect_scope = bcast_scope;
541 b_ptr->priority = priority;
542 INIT_LIST_HEAD(&b_ptr->cong_links);
543 INIT_LIST_HEAD(&b_ptr->links);
545 b_ptr->link_req = disc_init_link_req(b_ptr, &m_ptr->bcast_addr,
548 b_ptr->publ.lock = SPIN_LOCK_UNLOCKED;
549 write_unlock_bh(&net_lock);
550 info("Enabled bearer <%s>, discovery domain %s\n",
551 name, addr_string_fill(addr_string, bcast_scope));
554 write_unlock_bh(&net_lock);
559 * tipc_block_bearer(): Block the bearer with the given name,
560 * and reset all its links
563 int tipc_block_bearer(const char *name)
565 struct bearer *b_ptr = 0;
567 struct link *temp_l_ptr;
569 if (tipc_mode != TIPC_NET_MODE)
572 read_lock_bh(&net_lock);
573 b_ptr = bearer_find(name);
575 warn("Attempt to block unknown bearer <%s>\n", name);
576 read_unlock_bh(&net_lock);
580 spin_lock_bh(&b_ptr->publ.lock);
581 b_ptr->publ.blocked = 1;
582 list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) {
583 struct node *n_ptr = l_ptr->owner;
585 spin_lock_bh(&n_ptr->lock);
587 spin_unlock_bh(&n_ptr->lock);
589 spin_unlock_bh(&b_ptr->publ.lock);
590 read_unlock_bh(&net_lock);
591 info("Blocked bearer <%s>\n", name);
598 * Note: This routine assumes caller holds net_lock.
601 static int bearer_disable(const char *name)
603 struct bearer *b_ptr;
605 struct link *temp_l_ptr;
607 if (tipc_mode != TIPC_NET_MODE)
610 b_ptr = bearer_find(name);
612 warn("Attempt to disable unknown bearer <%s>\n", name);
616 disc_stop_link_req(b_ptr->link_req);
617 spin_lock_bh(&b_ptr->publ.lock);
618 b_ptr->link_req = NULL;
619 b_ptr->publ.blocked = 1;
620 if (b_ptr->media->disable_bearer) {
621 spin_unlock_bh(&b_ptr->publ.lock);
622 write_unlock_bh(&net_lock);
623 b_ptr->media->disable_bearer(&b_ptr->publ);
624 write_lock_bh(&net_lock);
625 spin_lock_bh(&b_ptr->publ.lock);
627 list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) {
630 spin_unlock_bh(&b_ptr->publ.lock);
631 info("Disabled bearer <%s>\n", name);
632 memset(b_ptr, 0, sizeof(struct bearer));
636 int tipc_disable_bearer(const char *name)
640 write_lock_bh(&net_lock);
641 res = bearer_disable(name);
642 write_unlock_bh(&net_lock);
648 int bearer_init(void)
652 write_lock_bh(&net_lock);
653 bearers = kmalloc(MAX_BEARERS * sizeof(struct bearer), GFP_ATOMIC);
654 media_list = kmalloc(MAX_MEDIA * sizeof(struct media), GFP_ATOMIC);
655 if (bearers && media_list) {
656 memset(bearers, 0, MAX_BEARERS * sizeof(struct bearer));
657 memset(media_list, 0, MAX_MEDIA * sizeof(struct media));
666 write_unlock_bh(&net_lock);
670 void bearer_stop(void)
677 for (i = 0; i < MAX_BEARERS; i++) {
678 if (bearers[i].active)
679 bearers[i].publ.blocked = 1;
681 for (i = 0; i < MAX_BEARERS; i++) {
682 if (bearers[i].active)
683 bearer_disable(bearers[i].publ.name);