2 * net/tipc/bearer.c: TIPC bearer code
4 * Copyright (c) 1996-2006, Ericsson AB
5 * Copyright (c) 2004-2006, Wind River Systems
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
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.
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.
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.
43 #define MAX_ADDR_STR 32
45 static struct media media_list[MAX_MEDIA];
46 static u32 media_count = 0;
48 struct bearer tipc_bearers[MAX_BEARERS];
51 * media_name_valid - validate media name
53 * Returns 1 if media name is valid, otherwise 0.
56 static int media_name_valid(const char *name)
61 if ((len + 1) > TIPC_MAX_MEDIA_NAME)
63 return strspn(name, tipc_alphabet) == len;
67 * media_find - locates specified media object by name
70 static struct media *media_find(const char *name)
75 for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
76 if (!strcmp(m_ptr->name, name))
83 * tipc_register_media - register a media type
85 * Bearers for this media type must be activated separately at a later stage.
88 int tipc_register_media(u32 media_type,
90 int (*enable)(struct tipc_bearer *),
91 void (*disable)(struct tipc_bearer *),
92 int (*send_msg)(struct sk_buff *,
94 struct tipc_media_addr *),
95 char *(*addr2str)(struct tipc_media_addr *a,
96 char *str_buf, int str_size),
97 struct tipc_media_addr *bcast_addr,
98 const u32 bearer_priority,
99 const u32 link_tolerance, /* [ms] */
100 const u32 send_window_limit)
107 write_lock_bh(&tipc_net_lock);
109 if (tipc_mode != TIPC_NET_MODE) {
110 warn("Media <%s> rejected, not in networked mode yet\n", name);
113 if (!media_name_valid(name)) {
114 warn("Media <%s> rejected, illegal name\n", name);
118 warn("Media <%s> rejected, no broadcast address\n", name);
121 if ((bearer_priority < TIPC_MIN_LINK_PRI) ||
122 (bearer_priority > TIPC_MAX_LINK_PRI)) {
123 warn("Media <%s> rejected, illegal priority (%u)\n", name,
127 if ((link_tolerance < TIPC_MIN_LINK_TOL) ||
128 (link_tolerance > TIPC_MAX_LINK_TOL)) {
129 warn("Media <%s> rejected, illegal tolerance (%u)\n", name,
134 media_id = media_count++;
135 if (media_id >= MAX_MEDIA) {
136 warn("Media <%s> rejected, media limit reached (%u)\n", name,
141 for (i = 0; i < media_id; i++) {
142 if (media_list[i].type_id == media_type) {
143 warn("Media <%s> rejected, duplicate type (%u)\n", name,
148 if (!strcmp(name, media_list[i].name)) {
149 warn("Media <%s> rejected, duplicate name\n", name);
155 m_ptr = &media_list[media_id];
156 m_ptr->type_id = media_type;
157 m_ptr->send_msg = send_msg;
158 m_ptr->enable_bearer = enable;
159 m_ptr->disable_bearer = disable;
160 m_ptr->addr2str = addr2str;
161 memcpy(&m_ptr->bcast_addr, bcast_addr, sizeof(*bcast_addr));
163 strcpy(m_ptr->name, name);
164 m_ptr->priority = bearer_priority;
165 m_ptr->tolerance = link_tolerance;
166 m_ptr->window = send_window_limit;
167 dbg("Media <%s> registered\n", name);
170 write_unlock_bh(&tipc_net_lock);
175 * tipc_media_addr_printf - record media address in print buffer
178 void tipc_media_addr_printf(struct print_buf *pb, struct tipc_media_addr *a)
184 media_type = ntohl(a->type);
185 for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
186 if (m_ptr->type_id == media_type)
190 if ((i < media_count) && (m_ptr->addr2str != NULL)) {
191 char addr_str[MAX_ADDR_STR];
193 tipc_printf(pb, "%s(%s)", m_ptr->name,
194 m_ptr->addr2str(a, addr_str, sizeof(addr_str)));
196 unchar *addr = (unchar *)&a->dev_addr;
198 tipc_printf(pb, "UNKNOWN(%u)", media_type);
199 for (i = 0; i < (sizeof(*a) - sizeof(a->type)); i++) {
200 tipc_printf(pb, "-%02x", addr[i]);
206 * tipc_media_get_names - record names of registered media in buffer
209 struct sk_buff *tipc_media_get_names(void)
215 buf = tipc_cfg_reply_alloc(MAX_MEDIA * TLV_SPACE(TIPC_MAX_MEDIA_NAME));
219 read_lock_bh(&tipc_net_lock);
220 for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
221 tipc_cfg_append_tlv(buf, TIPC_TLV_MEDIA_NAME, m_ptr->name,
222 strlen(m_ptr->name) + 1);
224 read_unlock_bh(&tipc_net_lock);
229 * bearer_name_validate - validate & (optionally) deconstruct bearer name
230 * @name - ptr to bearer name string
231 * @name_parts - ptr to area for bearer name components (or NULL if not needed)
233 * Returns 1 if bearer name is valid, otherwise 0.
236 static int bearer_name_validate(const char *name,
237 struct bearer_name *name_parts)
239 char name_copy[TIPC_MAX_BEARER_NAME];
245 /* copy bearer name & ensure length is OK */
247 name_copy[TIPC_MAX_BEARER_NAME - 1] = 0;
248 /* need above in case non-Posix strncpy() doesn't pad with nulls */
249 strncpy(name_copy, name, TIPC_MAX_BEARER_NAME);
250 if (name_copy[TIPC_MAX_BEARER_NAME - 1] != 0)
253 /* ensure all component parts of bearer name are present */
255 media_name = name_copy;
256 if ((if_name = strchr(media_name, ':')) == NULL)
259 media_len = if_name - media_name;
260 if_len = strlen(if_name) + 1;
262 /* validate component parts of bearer name */
264 if ((media_len <= 1) || (media_len > TIPC_MAX_MEDIA_NAME) ||
265 (if_len <= 1) || (if_len > TIPC_MAX_IF_NAME) ||
266 (strspn(media_name, tipc_alphabet) != (media_len - 1)) ||
267 (strspn(if_name, tipc_alphabet) != (if_len - 1)))
270 /* return bearer name components, if necessary */
273 strcpy(name_parts->media_name, media_name);
274 strcpy(name_parts->if_name, if_name);
280 * bearer_find - locates bearer object with matching bearer name
283 static struct bearer *bearer_find(const char *name)
285 struct bearer *b_ptr;
288 for (i = 0, b_ptr = tipc_bearers; i < MAX_BEARERS; i++, b_ptr++) {
289 if (b_ptr->active && (!strcmp(b_ptr->publ.name, name)))
296 * tipc_bearer_find_interface - locates bearer object with matching interface name
299 struct bearer *tipc_bearer_find_interface(const char *if_name)
301 struct bearer *b_ptr;
305 for (i = 0, b_ptr = tipc_bearers; i < MAX_BEARERS; i++, b_ptr++) {
308 b_if_name = strchr(b_ptr->publ.name, ':') + 1;
309 if (!strcmp(b_if_name, if_name))
316 * tipc_bearer_get_names - record names of bearers in buffer
319 struct sk_buff *tipc_bearer_get_names(void)
323 struct bearer *b_ptr;
326 buf = tipc_cfg_reply_alloc(MAX_BEARERS * TLV_SPACE(TIPC_MAX_BEARER_NAME));
330 read_lock_bh(&tipc_net_lock);
331 for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
332 for (j = 0; j < MAX_BEARERS; j++) {
333 b_ptr = &tipc_bearers[j];
334 if (b_ptr->active && (b_ptr->media == m_ptr)) {
335 tipc_cfg_append_tlv(buf, TIPC_TLV_BEARER_NAME,
337 strlen(b_ptr->publ.name) + 1);
341 read_unlock_bh(&tipc_net_lock);
345 void tipc_bearer_add_dest(struct bearer *b_ptr, u32 dest)
347 tipc_nmap_add(&b_ptr->nodes, dest);
348 tipc_disc_update_link_req(b_ptr->link_req);
349 tipc_bcbearer_sort();
352 void tipc_bearer_remove_dest(struct bearer *b_ptr, u32 dest)
354 tipc_nmap_remove(&b_ptr->nodes, dest);
355 tipc_disc_update_link_req(b_ptr->link_req);
356 tipc_bcbearer_sort();
360 * bearer_push(): Resolve bearer congestion. Force the waiting
361 * links to push out their unsent packets, one packet per link
362 * per iteration, until all packets are gone or congestion reoccurs.
363 * 'tipc_net_lock' is read_locked when this function is called
364 * bearer.lock must be taken before calling
365 * Returns binary true(1) ore false(0)
367 static int bearer_push(struct bearer *b_ptr)
370 struct link *ln, *tln;
372 if (b_ptr->publ.blocked)
375 while (!list_empty(&b_ptr->cong_links) && (res != PUSH_FAILED)) {
376 list_for_each_entry_safe(ln, tln, &b_ptr->cong_links, link_list) {
377 res = tipc_link_push_packet(ln);
378 if (res == PUSH_FAILED)
380 if (res == PUSH_FINISHED)
381 list_move_tail(&ln->link_list, &b_ptr->links);
384 return list_empty(&b_ptr->cong_links);
387 void tipc_bearer_lock_push(struct bearer *b_ptr)
391 spin_lock_bh(&b_ptr->publ.lock);
392 res = bearer_push(b_ptr);
393 spin_unlock_bh(&b_ptr->publ.lock);
395 tipc_bcbearer_push();
400 * Interrupt enabling new requests after bearer congestion or blocking:
403 void tipc_continue(struct tipc_bearer *tb_ptr)
405 struct bearer *b_ptr = (struct bearer *)tb_ptr;
407 spin_lock_bh(&b_ptr->publ.lock);
408 b_ptr->continue_count++;
409 if (!list_empty(&b_ptr->cong_links))
410 tipc_k_signal((Handler)tipc_bearer_lock_push, (unsigned long)b_ptr);
411 b_ptr->publ.blocked = 0;
412 spin_unlock_bh(&b_ptr->publ.lock);
416 * Schedule link for sending of messages after the bearer
417 * has been deblocked by 'continue()'. This method is called
418 * when somebody tries to send a message via this link while
419 * the bearer is congested. 'tipc_net_lock' is in read_lock here
420 * bearer.lock is busy
423 static void tipc_bearer_schedule_unlocked(struct bearer *b_ptr, struct link *l_ptr)
425 list_move_tail(&l_ptr->link_list, &b_ptr->cong_links);
429 * Schedule link for sending of messages after the bearer
430 * has been deblocked by 'continue()'. This method is called
431 * when somebody tries to send a message via this link while
432 * the bearer is congested. 'tipc_net_lock' is in read_lock here,
433 * bearer.lock is free
436 void tipc_bearer_schedule(struct bearer *b_ptr, struct link *l_ptr)
438 spin_lock_bh(&b_ptr->publ.lock);
439 tipc_bearer_schedule_unlocked(b_ptr, l_ptr);
440 spin_unlock_bh(&b_ptr->publ.lock);
445 * tipc_bearer_resolve_congestion(): Check if there is bearer congestion,
446 * and if there is, try to resolve it before returning.
447 * 'tipc_net_lock' is read_locked when this function is called
449 int tipc_bearer_resolve_congestion(struct bearer *b_ptr, struct link *l_ptr)
453 if (list_empty(&b_ptr->cong_links))
455 spin_lock_bh(&b_ptr->publ.lock);
456 if (!bearer_push(b_ptr)) {
457 tipc_bearer_schedule_unlocked(b_ptr, l_ptr);
460 spin_unlock_bh(&b_ptr->publ.lock);
465 * tipc_bearer_congested - determines if bearer is currently congested
468 int tipc_bearer_congested(struct bearer *b_ptr, struct link *l_ptr)
470 if (unlikely(b_ptr->publ.blocked))
472 if (likely(list_empty(&b_ptr->cong_links)))
474 return !tipc_bearer_resolve_congestion(b_ptr, l_ptr);
478 * tipc_enable_bearer - enable bearer with the given name
481 int tipc_enable_bearer(const char *name, u32 bcast_scope, u32 priority)
483 struct bearer *b_ptr;
485 struct bearer_name b_name;
486 char addr_string[16];
492 if (tipc_mode != TIPC_NET_MODE) {
493 warn("Bearer <%s> rejected, not supported in standalone mode\n",
497 if (!bearer_name_validate(name, &b_name)) {
498 warn("Bearer <%s> rejected, illegal name\n", name);
501 if (!tipc_addr_domain_valid(bcast_scope) ||
502 !tipc_in_scope(bcast_scope, tipc_own_addr)) {
503 warn("Bearer <%s> rejected, illegal broadcast scope\n", name);
506 if ((priority < TIPC_MIN_LINK_PRI ||
507 priority > TIPC_MAX_LINK_PRI) &&
508 (priority != TIPC_MEDIA_LINK_PRI)) {
509 warn("Bearer <%s> rejected, illegal priority\n", name);
513 write_lock_bh(&tipc_net_lock);
515 m_ptr = media_find(b_name.media_name);
517 warn("Bearer <%s> rejected, media <%s> not registered\n", name,
522 if (priority == TIPC_MEDIA_LINK_PRI)
523 priority = m_ptr->priority;
526 bearer_id = MAX_BEARERS;
528 for (i = MAX_BEARERS; i-- != 0; ) {
529 if (!tipc_bearers[i].active) {
533 if (!strcmp(name, tipc_bearers[i].publ.name)) {
534 warn("Bearer <%s> rejected, already enabled\n", name);
537 if ((tipc_bearers[i].priority == priority) &&
538 (++with_this_prio > 2)) {
539 if (priority-- == 0) {
540 warn("Bearer <%s> rejected, duplicate priority\n",
544 warn("Bearer <%s> priority adjustment required %u->%u\n",
545 name, priority + 1, priority);
549 if (bearer_id >= MAX_BEARERS) {
550 warn("Bearer <%s> rejected, bearer limit reached (%u)\n",
555 b_ptr = &tipc_bearers[bearer_id];
556 strcpy(b_ptr->publ.name, name);
557 res = m_ptr->enable_bearer(&b_ptr->publ);
559 warn("Bearer <%s> rejected, enable failure (%d)\n", name, -res);
563 b_ptr->identity = bearer_id;
564 b_ptr->media = m_ptr;
565 b_ptr->net_plane = bearer_id + 'A';
567 b_ptr->detect_scope = bcast_scope;
568 b_ptr->priority = priority;
569 INIT_LIST_HEAD(&b_ptr->cong_links);
570 INIT_LIST_HEAD(&b_ptr->links);
572 b_ptr->link_req = tipc_disc_init_link_req(b_ptr, &m_ptr->bcast_addr,
575 spin_lock_init(&b_ptr->publ.lock);
576 write_unlock_bh(&tipc_net_lock);
577 info("Enabled bearer <%s>, discovery domain %s, priority %u\n",
578 name, tipc_addr_string_fill(addr_string, bcast_scope), priority);
581 write_unlock_bh(&tipc_net_lock);
586 * tipc_block_bearer(): Block the bearer with the given name,
587 * and reset all its links
590 int tipc_block_bearer(const char *name)
592 struct bearer *b_ptr = NULL;
594 struct link *temp_l_ptr;
596 read_lock_bh(&tipc_net_lock);
597 b_ptr = bearer_find(name);
599 warn("Attempt to block unknown bearer <%s>\n", name);
600 read_unlock_bh(&tipc_net_lock);
604 info("Blocking bearer <%s>\n", name);
605 spin_lock_bh(&b_ptr->publ.lock);
606 b_ptr->publ.blocked = 1;
607 list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) {
608 struct tipc_node *n_ptr = l_ptr->owner;
610 spin_lock_bh(&n_ptr->lock);
611 tipc_link_reset(l_ptr);
612 spin_unlock_bh(&n_ptr->lock);
614 spin_unlock_bh(&b_ptr->publ.lock);
615 read_unlock_bh(&tipc_net_lock);
622 * Note: This routine assumes caller holds tipc_net_lock.
625 static void bearer_disable(struct bearer *b_ptr)
628 struct link *temp_l_ptr;
630 info("Disabling bearer <%s>\n", b_ptr->publ.name);
631 tipc_disc_stop_link_req(b_ptr->link_req);
632 spin_lock_bh(&b_ptr->publ.lock);
633 b_ptr->link_req = NULL;
634 b_ptr->publ.blocked = 1;
635 b_ptr->media->disable_bearer(&b_ptr->publ);
636 list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) {
637 tipc_link_delete(l_ptr);
639 spin_unlock_bh(&b_ptr->publ.lock);
640 memset(b_ptr, 0, sizeof(struct bearer));
643 int tipc_disable_bearer(const char *name)
645 struct bearer *b_ptr;
648 write_lock_bh(&tipc_net_lock);
649 b_ptr = bearer_find(name);
651 warn("Attempt to disable unknown bearer <%s>\n", name);
654 bearer_disable(b_ptr);
657 write_unlock_bh(&tipc_net_lock);
663 void tipc_bearer_stop(void)
667 for (i = 0; i < MAX_BEARERS; i++) {
668 if (tipc_bearers[i].active)
669 bearer_disable(&tipc_bearers[i]);