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
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.
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)
76 for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
77 if (!strcmp(m_ptr->name, name))
84 * tipc_register_media - register a media type
86 * Bearers for this media type must be activated separately at a later stage.
89 int tipc_register_media(u32 media_type,
91 int (*enable)(struct tipc_bearer *),
92 void (*disable)(struct tipc_bearer *),
93 int (*send_msg)(struct sk_buff *,
95 struct tipc_media_addr *),
96 char *(*addr2str)(struct tipc_media_addr *a,
97 char *str_buf, int str_size),
98 struct tipc_media_addr *bcast_addr,
99 const u32 bearer_priority,
100 const u32 link_tolerance, /* [ms] */
101 const u32 send_window_limit)
108 write_lock_bh(&tipc_net_lock);
110 if (tipc_mode != TIPC_NET_MODE) {
111 warn("Media <%s> rejected, not in networked mode yet\n", name);
114 if (!media_name_valid(name)) {
115 warn("Media <%s> rejected, illegal name\n", name);
119 warn("Media <%s> rejected, no broadcast address\n", name);
122 if ((bearer_priority < TIPC_MIN_LINK_PRI) ||
123 (bearer_priority > TIPC_MAX_LINK_PRI)) {
124 warn("Media <%s> rejected, illegal priority (%u)\n", name,
128 if ((link_tolerance < TIPC_MIN_LINK_TOL) ||
129 (link_tolerance > TIPC_MAX_LINK_TOL)) {
130 warn("Media <%s> rejected, illegal tolerance (%u)\n", name,
135 media_id = media_count++;
136 if (media_id >= MAX_MEDIA) {
137 warn("Media <%s> rejected, media limit reached (%u)\n", name,
142 for (i = 0; i < media_id; i++) {
143 if (media_list[i].type_id == media_type) {
144 warn("Media <%s> rejected, duplicate type (%u)\n", name,
149 if (!strcmp(name, media_list[i].name)) {
150 warn("Media <%s> rejected, duplicate name\n", name);
156 m_ptr = &media_list[media_id];
157 m_ptr->type_id = media_type;
158 m_ptr->send_msg = send_msg;
159 m_ptr->enable_bearer = enable;
160 m_ptr->disable_bearer = disable;
161 m_ptr->addr2str = addr2str;
162 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;
169 write_unlock_bh(&tipc_net_lock);
174 * tipc_media_addr_printf - record media address in print buffer
177 void tipc_media_addr_printf(struct print_buf *pb, struct tipc_media_addr *a)
183 media_type = ntohl(a->type);
184 for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
185 if (m_ptr->type_id == media_type)
189 if ((i < media_count) && (m_ptr->addr2str != NULL)) {
190 char addr_str[MAX_ADDR_STR];
192 tipc_printf(pb, "%s(%s)", m_ptr->name,
193 m_ptr->addr2str(a, addr_str, sizeof(addr_str)));
195 unchar *addr = (unchar *)&a->dev_addr;
197 tipc_printf(pb, "UNKNOWN(%u)", media_type);
198 for (i = 0; i < (sizeof(*a) - sizeof(a->type)); i++)
199 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_name = strchr(media_name, ':');
258 media_len = if_name - media_name;
259 if_len = strlen(if_name) + 1;
261 /* validate component parts of bearer name */
263 if ((media_len <= 1) || (media_len > TIPC_MAX_MEDIA_NAME) ||
264 (if_len <= 1) || (if_len > TIPC_MAX_IF_NAME) ||
265 (strspn(media_name, tipc_alphabet) != (media_len - 1)) ||
266 (strspn(if_name, tipc_alphabet) != (if_len - 1)))
269 /* return bearer name components, if necessary */
272 strcpy(name_parts->media_name, media_name);
273 strcpy(name_parts->if_name, if_name);
279 * bearer_find - locates bearer object with matching bearer name
282 static struct tipc_bearer *bearer_find(const char *name)
284 struct tipc_bearer *b_ptr;
287 for (i = 0, b_ptr = tipc_bearers; i < MAX_BEARERS; i++, b_ptr++) {
288 if (b_ptr->active && (!strcmp(b_ptr->name, name)))
295 * tipc_bearer_find_interface - locates bearer object with matching interface name
298 struct tipc_bearer *tipc_bearer_find_interface(const char *if_name)
300 struct tipc_bearer *b_ptr;
304 for (i = 0, b_ptr = tipc_bearers; i < MAX_BEARERS; i++, b_ptr++) {
307 b_if_name = strchr(b_ptr->name, ':') + 1;
308 if (!strcmp(b_if_name, if_name))
315 * tipc_bearer_get_names - record names of bearers in buffer
318 struct sk_buff *tipc_bearer_get_names(void)
322 struct tipc_bearer *b_ptr;
325 buf = tipc_cfg_reply_alloc(MAX_BEARERS * TLV_SPACE(TIPC_MAX_BEARER_NAME));
329 read_lock_bh(&tipc_net_lock);
330 for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
331 for (j = 0; j < MAX_BEARERS; j++) {
332 b_ptr = &tipc_bearers[j];
333 if (b_ptr->active && (b_ptr->media == m_ptr)) {
334 tipc_cfg_append_tlv(buf, TIPC_TLV_BEARER_NAME,
336 strlen(b_ptr->name) + 1);
340 read_unlock_bh(&tipc_net_lock);
344 void tipc_bearer_add_dest(struct tipc_bearer *b_ptr, u32 dest)
346 tipc_nmap_add(&b_ptr->nodes, dest);
347 tipc_bcbearer_sort();
348 tipc_disc_add_dest(b_ptr->link_req);
351 void tipc_bearer_remove_dest(struct tipc_bearer *b_ptr, u32 dest)
353 tipc_nmap_remove(&b_ptr->nodes, dest);
354 tipc_bcbearer_sort();
355 tipc_disc_remove_dest(b_ptr->link_req);
359 * bearer_push(): Resolve bearer congestion. Force the waiting
360 * links to push out their unsent packets, one packet per link
361 * per iteration, until all packets are gone or congestion reoccurs.
362 * 'tipc_net_lock' is read_locked when this function is called
363 * bearer.lock must be taken before calling
364 * Returns binary true(1) ore false(0)
366 static int bearer_push(struct tipc_bearer *b_ptr)
369 struct link *ln, *tln;
374 while (!list_empty(&b_ptr->cong_links) && (res != PUSH_FAILED)) {
375 list_for_each_entry_safe(ln, tln, &b_ptr->cong_links, link_list) {
376 res = tipc_link_push_packet(ln);
377 if (res == PUSH_FAILED)
379 if (res == PUSH_FINISHED)
380 list_move_tail(&ln->link_list, &b_ptr->links);
383 return list_empty(&b_ptr->cong_links);
386 void tipc_bearer_lock_push(struct tipc_bearer *b_ptr)
390 spin_lock_bh(&b_ptr->lock);
391 res = bearer_push(b_ptr);
392 spin_unlock_bh(&b_ptr->lock);
394 tipc_bcbearer_push();
399 * Interrupt enabling new requests after bearer congestion or blocking:
402 void tipc_continue(struct tipc_bearer *b_ptr)
404 spin_lock_bh(&b_ptr->lock);
405 b_ptr->continue_count++;
406 if (!list_empty(&b_ptr->cong_links))
407 tipc_k_signal((Handler)tipc_bearer_lock_push, (unsigned long)b_ptr);
409 spin_unlock_bh(&b_ptr->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. 'tipc_net_lock' is in read_lock here
417 * bearer.lock is busy
420 static void tipc_bearer_schedule_unlocked(struct tipc_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. 'tipc_net_lock' is in read_lock here,
430 * bearer.lock is free
433 void tipc_bearer_schedule(struct tipc_bearer *b_ptr, struct link *l_ptr)
435 spin_lock_bh(&b_ptr->lock);
436 tipc_bearer_schedule_unlocked(b_ptr, l_ptr);
437 spin_unlock_bh(&b_ptr->lock);
442 * tipc_bearer_resolve_congestion(): Check if there is bearer congestion,
443 * and if there is, try to resolve it before returning.
444 * 'tipc_net_lock' is read_locked when this function is called
446 int tipc_bearer_resolve_congestion(struct tipc_bearer *b_ptr, struct link *l_ptr)
450 if (list_empty(&b_ptr->cong_links))
452 spin_lock_bh(&b_ptr->lock);
453 if (!bearer_push(b_ptr)) {
454 tipc_bearer_schedule_unlocked(b_ptr, l_ptr);
457 spin_unlock_bh(&b_ptr->lock);
462 * tipc_bearer_congested - determines if bearer is currently congested
465 int tipc_bearer_congested(struct tipc_bearer *b_ptr, struct link *l_ptr)
467 if (unlikely(b_ptr->blocked))
469 if (likely(list_empty(&b_ptr->cong_links)))
471 return !tipc_bearer_resolve_congestion(b_ptr, l_ptr);
475 * tipc_enable_bearer - enable bearer with the given name
478 int tipc_enable_bearer(const char *name, u32 disc_domain, u32 priority)
480 struct tipc_bearer *b_ptr;
482 struct bearer_name b_name;
483 char addr_string[16];
489 if (tipc_mode != TIPC_NET_MODE) {
490 warn("Bearer <%s> rejected, not supported in standalone mode\n",
494 if (!bearer_name_validate(name, &b_name)) {
495 warn("Bearer <%s> rejected, illegal name\n", name);
498 if (tipc_addr_domain_valid(disc_domain) &&
499 (disc_domain != tipc_own_addr)) {
500 if (tipc_in_scope(disc_domain, tipc_own_addr)) {
501 disc_domain = tipc_own_addr & TIPC_CLUSTER_MASK;
502 res = 0; /* accept any node in own cluster */
503 } else if (in_own_cluster(disc_domain))
504 res = 0; /* accept specified node in own cluster */
507 warn("Bearer <%s> rejected, illegal discovery domain\n", name);
510 if ((priority < TIPC_MIN_LINK_PRI ||
511 priority > TIPC_MAX_LINK_PRI) &&
512 (priority != TIPC_MEDIA_LINK_PRI)) {
513 warn("Bearer <%s> rejected, illegal priority\n", name);
517 write_lock_bh(&tipc_net_lock);
519 m_ptr = media_find(b_name.media_name);
521 warn("Bearer <%s> rejected, media <%s> not registered\n", name,
526 if (priority == TIPC_MEDIA_LINK_PRI)
527 priority = m_ptr->priority;
530 bearer_id = MAX_BEARERS;
532 for (i = MAX_BEARERS; i-- != 0; ) {
533 if (!tipc_bearers[i].active) {
537 if (!strcmp(name, tipc_bearers[i].name)) {
538 warn("Bearer <%s> rejected, already enabled\n", name);
541 if ((tipc_bearers[i].priority == priority) &&
542 (++with_this_prio > 2)) {
543 if (priority-- == 0) {
544 warn("Bearer <%s> rejected, duplicate priority\n",
548 warn("Bearer <%s> priority adjustment required %u->%u\n",
549 name, priority + 1, priority);
553 if (bearer_id >= MAX_BEARERS) {
554 warn("Bearer <%s> rejected, bearer limit reached (%u)\n",
559 b_ptr = &tipc_bearers[bearer_id];
560 strcpy(b_ptr->name, name);
561 res = m_ptr->enable_bearer(b_ptr);
563 warn("Bearer <%s> rejected, enable failure (%d)\n", name, -res);
567 b_ptr->identity = bearer_id;
568 b_ptr->media = m_ptr;
569 b_ptr->net_plane = bearer_id + 'A';
571 b_ptr->priority = priority;
572 INIT_LIST_HEAD(&b_ptr->cong_links);
573 INIT_LIST_HEAD(&b_ptr->links);
574 spin_lock_init(&b_ptr->lock);
576 res = tipc_disc_create(b_ptr, &m_ptr->bcast_addr, disc_domain);
578 bearer_disable(b_ptr);
579 warn("Bearer <%s> rejected, discovery object creation failed\n",
583 info("Enabled bearer <%s>, discovery domain %s, priority %u\n",
584 name, tipc_addr_string_fill(addr_string, disc_domain), priority);
586 write_unlock_bh(&tipc_net_lock);
591 * tipc_block_bearer(): Block the bearer with the given name,
592 * and reset all its links
595 int tipc_block_bearer(const char *name)
597 struct tipc_bearer *b_ptr = NULL;
599 struct link *temp_l_ptr;
601 read_lock_bh(&tipc_net_lock);
602 b_ptr = bearer_find(name);
604 warn("Attempt to block unknown bearer <%s>\n", name);
605 read_unlock_bh(&tipc_net_lock);
609 info("Blocking bearer <%s>\n", name);
610 spin_lock_bh(&b_ptr->lock);
612 list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) {
613 struct tipc_node *n_ptr = l_ptr->owner;
615 spin_lock_bh(&n_ptr->lock);
616 tipc_link_reset(l_ptr);
617 spin_unlock_bh(&n_ptr->lock);
619 spin_unlock_bh(&b_ptr->lock);
620 read_unlock_bh(&tipc_net_lock);
627 * Note: This routine assumes caller holds tipc_net_lock.
630 static void bearer_disable(struct tipc_bearer *b_ptr)
633 struct link *temp_l_ptr;
635 info("Disabling bearer <%s>\n", b_ptr->name);
636 spin_lock_bh(&b_ptr->lock);
638 b_ptr->media->disable_bearer(b_ptr);
639 list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) {
640 tipc_link_delete(l_ptr);
643 tipc_disc_delete(b_ptr->link_req);
644 spin_unlock_bh(&b_ptr->lock);
645 memset(b_ptr, 0, sizeof(struct tipc_bearer));
648 int tipc_disable_bearer(const char *name)
650 struct tipc_bearer *b_ptr;
653 write_lock_bh(&tipc_net_lock);
654 b_ptr = bearer_find(name);
656 warn("Attempt to disable unknown bearer <%s>\n", name);
659 bearer_disable(b_ptr);
662 write_unlock_bh(&tipc_net_lock);
668 void tipc_bearer_stop(void)
672 for (i = 0; i < MAX_BEARERS; i++) {
673 if (tipc_bearers[i].active)
674 bearer_disable(&tipc_bearers[i]);