ipv4: Use universal hash for ARP.
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / tipc / bearer.c
blob85eba9c08ee9667e978d548c0aaea4d7506b2e5f
1 /*
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
6 * All rights reserved.
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.
37 #include "core.h"
38 #include "config.h"
39 #include "bearer.h"
40 #include "discover.h"
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);
51 /**
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)
59 u32 len;
61 len = strlen(name);
62 if ((len + 1) > TIPC_MAX_MEDIA_NAME)
63 return 0;
64 return strspn(name, tipc_alphabet) == len;
67 /**
68 * media_find - locates specified media object by name
71 static struct media *media_find(const char *name)
73 struct media *m_ptr;
74 u32 i;
76 for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
77 if (!strcmp(m_ptr->name, name))
78 return m_ptr;
80 return NULL;
83 /**
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,
90 char *name,
91 int (*enable)(struct tipc_bearer *),
92 void (*disable)(struct tipc_bearer *),
93 int (*send_msg)(struct sk_buff *,
94 struct tipc_bearer *,
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)
103 struct media *m_ptr;
104 u32 media_id;
105 u32 i;
106 int res = -EINVAL;
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);
112 goto exit;
114 if (!media_name_valid(name)) {
115 warn("Media <%s> rejected, illegal name\n", name);
116 goto exit;
118 if (!bcast_addr) {
119 warn("Media <%s> rejected, no broadcast address\n", name);
120 goto exit;
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,
125 bearer_priority);
126 goto exit;
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,
131 link_tolerance);
132 goto exit;
135 media_id = media_count++;
136 if (media_id >= MAX_MEDIA) {
137 warn("Media <%s> rejected, media limit reached (%u)\n", name,
138 MAX_MEDIA);
139 media_count--;
140 goto exit;
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,
145 media_type);
146 media_count--;
147 goto exit;
149 if (!strcmp(name, media_list[i].name)) {
150 warn("Media <%s> rejected, duplicate name\n", name);
151 media_count--;
152 goto exit;
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;
167 res = 0;
168 exit:
169 write_unlock_bh(&tipc_net_lock);
170 return res;
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)
179 struct media *m_ptr;
180 u32 media_type;
181 u32 i;
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)
186 break;
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)));
194 } else {
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)
209 struct sk_buff *buf;
210 struct media *m_ptr;
211 int i;
213 buf = tipc_cfg_reply_alloc(MAX_MEDIA * TLV_SPACE(TIPC_MAX_MEDIA_NAME));
214 if (!buf)
215 return NULL;
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);
223 return buf;
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];
238 char *media_name;
239 char *if_name;
240 u32 media_len;
241 u32 if_len;
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)
249 return 0;
251 /* ensure all component parts of bearer name are present */
253 media_name = name_copy;
254 if_name = strchr(media_name, ':');
255 if (if_name == NULL)
256 return 0;
257 *(if_name++) = 0;
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)))
267 return 0;
269 /* return bearer name components, if necessary */
271 if (name_parts) {
272 strcpy(name_parts->media_name, media_name);
273 strcpy(name_parts->if_name, if_name);
275 return 1;
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;
285 u32 i;
287 for (i = 0, b_ptr = tipc_bearers; i < MAX_BEARERS; i++, b_ptr++) {
288 if (b_ptr->active && (!strcmp(b_ptr->name, name)))
289 return b_ptr;
291 return NULL;
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;
301 char *b_if_name;
302 u32 i;
304 for (i = 0, b_ptr = tipc_bearers; i < MAX_BEARERS; i++, b_ptr++) {
305 if (!b_ptr->active)
306 continue;
307 b_if_name = strchr(b_ptr->name, ':') + 1;
308 if (!strcmp(b_if_name, if_name))
309 return b_ptr;
311 return NULL;
315 * tipc_bearer_get_names - record names of bearers in buffer
318 struct sk_buff *tipc_bearer_get_names(void)
320 struct sk_buff *buf;
321 struct media *m_ptr;
322 struct tipc_bearer *b_ptr;
323 int i, j;
325 buf = tipc_cfg_reply_alloc(MAX_BEARERS * TLV_SPACE(TIPC_MAX_BEARER_NAME));
326 if (!buf)
327 return NULL;
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,
335 b_ptr->name,
336 strlen(b_ptr->name) + 1);
340 read_unlock_bh(&tipc_net_lock);
341 return buf;
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)
368 u32 res = 0;
369 struct link *ln, *tln;
371 if (b_ptr->blocked)
372 return 0;
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)
378 break;
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)
388 int res;
390 spin_lock_bh(&b_ptr->lock);
391 res = bearer_push(b_ptr);
392 spin_unlock_bh(&b_ptr->lock);
393 if (res)
394 tipc_bcbearer_push();
399 * Interrupt enabling new requests after bearer congestion or blocking:
400 * See bearer_send().
402 void tipc_continue(struct tipc_bearer *b_ptr)
404 spin_lock_bh(&b_ptr->lock);
405 if (!list_empty(&b_ptr->cong_links))
406 tipc_k_signal((Handler)tipc_bearer_lock_push, (unsigned long)b_ptr);
407 b_ptr->blocked = 0;
408 spin_unlock_bh(&b_ptr->lock);
412 * Schedule link for sending of messages after the bearer
413 * has been deblocked by 'continue()'. This method is called
414 * when somebody tries to send a message via this link while
415 * the bearer is congested. 'tipc_net_lock' is in read_lock here
416 * bearer.lock is busy
419 static void tipc_bearer_schedule_unlocked(struct tipc_bearer *b_ptr, struct link *l_ptr)
421 list_move_tail(&l_ptr->link_list, &b_ptr->cong_links);
425 * Schedule link for sending of messages after the bearer
426 * has been deblocked by 'continue()'. This method is called
427 * when somebody tries to send a message via this link while
428 * the bearer is congested. 'tipc_net_lock' is in read_lock here,
429 * bearer.lock is free
432 void tipc_bearer_schedule(struct tipc_bearer *b_ptr, struct link *l_ptr)
434 spin_lock_bh(&b_ptr->lock);
435 tipc_bearer_schedule_unlocked(b_ptr, l_ptr);
436 spin_unlock_bh(&b_ptr->lock);
441 * tipc_bearer_resolve_congestion(): Check if there is bearer congestion,
442 * and if there is, try to resolve it before returning.
443 * 'tipc_net_lock' is read_locked when this function is called
445 int tipc_bearer_resolve_congestion(struct tipc_bearer *b_ptr, struct link *l_ptr)
447 int res = 1;
449 if (list_empty(&b_ptr->cong_links))
450 return 1;
451 spin_lock_bh(&b_ptr->lock);
452 if (!bearer_push(b_ptr)) {
453 tipc_bearer_schedule_unlocked(b_ptr, l_ptr);
454 res = 0;
456 spin_unlock_bh(&b_ptr->lock);
457 return res;
461 * tipc_bearer_congested - determines if bearer is currently congested
464 int tipc_bearer_congested(struct tipc_bearer *b_ptr, struct link *l_ptr)
466 if (unlikely(b_ptr->blocked))
467 return 1;
468 if (likely(list_empty(&b_ptr->cong_links)))
469 return 0;
470 return !tipc_bearer_resolve_congestion(b_ptr, l_ptr);
474 * tipc_enable_bearer - enable bearer with the given name
477 int tipc_enable_bearer(const char *name, u32 disc_domain, u32 priority)
479 struct tipc_bearer *b_ptr;
480 struct media *m_ptr;
481 struct bearer_name b_name;
482 char addr_string[16];
483 u32 bearer_id;
484 u32 with_this_prio;
485 u32 i;
486 int res = -EINVAL;
488 if (tipc_mode != TIPC_NET_MODE) {
489 warn("Bearer <%s> rejected, not supported in standalone mode\n",
490 name);
491 return -ENOPROTOOPT;
493 if (!bearer_name_validate(name, &b_name)) {
494 warn("Bearer <%s> rejected, illegal name\n", name);
495 return -EINVAL;
497 if (tipc_addr_domain_valid(disc_domain) &&
498 (disc_domain != tipc_own_addr)) {
499 if (tipc_in_scope(disc_domain, tipc_own_addr)) {
500 disc_domain = tipc_own_addr & TIPC_CLUSTER_MASK;
501 res = 0; /* accept any node in own cluster */
502 } else if (in_own_cluster(disc_domain))
503 res = 0; /* accept specified node in own cluster */
505 if (res) {
506 warn("Bearer <%s> rejected, illegal discovery domain\n", name);
507 return -EINVAL;
509 if ((priority < TIPC_MIN_LINK_PRI ||
510 priority > TIPC_MAX_LINK_PRI) &&
511 (priority != TIPC_MEDIA_LINK_PRI)) {
512 warn("Bearer <%s> rejected, illegal priority\n", name);
513 return -EINVAL;
516 write_lock_bh(&tipc_net_lock);
518 m_ptr = media_find(b_name.media_name);
519 if (!m_ptr) {
520 warn("Bearer <%s> rejected, media <%s> not registered\n", name,
521 b_name.media_name);
522 goto exit;
525 if (priority == TIPC_MEDIA_LINK_PRI)
526 priority = m_ptr->priority;
528 restart:
529 bearer_id = MAX_BEARERS;
530 with_this_prio = 1;
531 for (i = MAX_BEARERS; i-- != 0; ) {
532 if (!tipc_bearers[i].active) {
533 bearer_id = i;
534 continue;
536 if (!strcmp(name, tipc_bearers[i].name)) {
537 warn("Bearer <%s> rejected, already enabled\n", name);
538 goto exit;
540 if ((tipc_bearers[i].priority == priority) &&
541 (++with_this_prio > 2)) {
542 if (priority-- == 0) {
543 warn("Bearer <%s> rejected, duplicate priority\n",
544 name);
545 goto exit;
547 warn("Bearer <%s> priority adjustment required %u->%u\n",
548 name, priority + 1, priority);
549 goto restart;
552 if (bearer_id >= MAX_BEARERS) {
553 warn("Bearer <%s> rejected, bearer limit reached (%u)\n",
554 name, MAX_BEARERS);
555 goto exit;
558 b_ptr = &tipc_bearers[bearer_id];
559 strcpy(b_ptr->name, name);
560 res = m_ptr->enable_bearer(b_ptr);
561 if (res) {
562 warn("Bearer <%s> rejected, enable failure (%d)\n", name, -res);
563 goto exit;
566 b_ptr->identity = bearer_id;
567 b_ptr->media = m_ptr;
568 b_ptr->net_plane = bearer_id + 'A';
569 b_ptr->active = 1;
570 b_ptr->priority = priority;
571 INIT_LIST_HEAD(&b_ptr->cong_links);
572 INIT_LIST_HEAD(&b_ptr->links);
573 spin_lock_init(&b_ptr->lock);
575 res = tipc_disc_create(b_ptr, &m_ptr->bcast_addr, disc_domain);
576 if (res) {
577 bearer_disable(b_ptr);
578 warn("Bearer <%s> rejected, discovery object creation failed\n",
579 name);
580 goto exit;
582 info("Enabled bearer <%s>, discovery domain %s, priority %u\n",
583 name, tipc_addr_string_fill(addr_string, disc_domain), priority);
584 exit:
585 write_unlock_bh(&tipc_net_lock);
586 return res;
590 * tipc_block_bearer(): Block the bearer with the given name,
591 * and reset all its links
594 int tipc_block_bearer(const char *name)
596 struct tipc_bearer *b_ptr = NULL;
597 struct link *l_ptr;
598 struct link *temp_l_ptr;
600 read_lock_bh(&tipc_net_lock);
601 b_ptr = bearer_find(name);
602 if (!b_ptr) {
603 warn("Attempt to block unknown bearer <%s>\n", name);
604 read_unlock_bh(&tipc_net_lock);
605 return -EINVAL;
608 info("Blocking bearer <%s>\n", name);
609 spin_lock_bh(&b_ptr->lock);
610 b_ptr->blocked = 1;
611 list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) {
612 struct tipc_node *n_ptr = l_ptr->owner;
614 spin_lock_bh(&n_ptr->lock);
615 tipc_link_reset(l_ptr);
616 spin_unlock_bh(&n_ptr->lock);
618 spin_unlock_bh(&b_ptr->lock);
619 read_unlock_bh(&tipc_net_lock);
620 return 0;
624 * bearer_disable -
626 * Note: This routine assumes caller holds tipc_net_lock.
629 static void bearer_disable(struct tipc_bearer *b_ptr)
631 struct link *l_ptr;
632 struct link *temp_l_ptr;
634 info("Disabling bearer <%s>\n", b_ptr->name);
635 spin_lock_bh(&b_ptr->lock);
636 b_ptr->blocked = 1;
637 b_ptr->media->disable_bearer(b_ptr);
638 list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) {
639 tipc_link_delete(l_ptr);
641 if (b_ptr->link_req)
642 tipc_disc_delete(b_ptr->link_req);
643 spin_unlock_bh(&b_ptr->lock);
644 memset(b_ptr, 0, sizeof(struct tipc_bearer));
647 int tipc_disable_bearer(const char *name)
649 struct tipc_bearer *b_ptr;
650 int res;
652 write_lock_bh(&tipc_net_lock);
653 b_ptr = bearer_find(name);
654 if (b_ptr == NULL) {
655 warn("Attempt to disable unknown bearer <%s>\n", name);
656 res = -EINVAL;
657 } else {
658 bearer_disable(b_ptr);
659 res = 0;
661 write_unlock_bh(&tipc_net_lock);
662 return res;
667 void tipc_bearer_stop(void)
669 u32 i;
671 for (i = 0; i < MAX_BEARERS; i++) {
672 if (tipc_bearers[i].active)
673 bearer_disable(&tipc_bearers[i]);
675 media_count = 0;