2 * net/tipc/node.c: TIPC node management routines
4 * Copyright (c) 2000-2006, Ericsson AB
5 * Copyright (c) 2005, 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
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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 #include "node_subscr.h"
47 #include "name_distr.h"
49 void node_print(struct print_buf *buf, struct node *n_ptr, char *str);
50 static void node_lost_contact(struct node *n_ptr);
51 static void node_established_contact(struct node *n_ptr);
53 struct node *tipc_nodes = NULL; /* sorted list of nodes within cluster */
57 struct node *tipc_node_create(u32 addr)
59 struct cluster *c_ptr;
61 struct node **curr_node;
63 n_ptr = kmalloc(sizeof(*n_ptr),GFP_ATOMIC);
65 warn("Node creation failed, no memory\n");
69 c_ptr = tipc_cltr_find(addr);
71 c_ptr = tipc_cltr_create(addr);
78 memset(n_ptr, 0, sizeof(*n_ptr));
80 n_ptr->lock = SPIN_LOCK_UNLOCKED;
81 INIT_LIST_HEAD(&n_ptr->nsub);
83 tipc_cltr_attach_node(c_ptr, n_ptr);
84 n_ptr->last_router = -1;
86 /* Insert node into ordered list */
87 for (curr_node = &tipc_nodes; *curr_node;
88 curr_node = &(*curr_node)->next) {
89 if (addr < (*curr_node)->addr) {
90 n_ptr->next = *curr_node;
98 void tipc_node_delete(struct node *n_ptr)
104 /* Not needed because links are already deleted via tipc_bearer_stop() */
108 for (l_num = 0; l_num < MAX_BEARERS; l_num++) {
109 link_delete(n_ptr->links[l_num]);
113 dbg("node %x deleted\n", n_ptr->addr);
119 * tipc_node_link_up - handle addition of link
121 * Link becomes active (alone or shared) or standby, depending on its priority.
124 void tipc_node_link_up(struct node *n_ptr, struct link *l_ptr)
126 struct link **active = &n_ptr->active_links[0];
128 info("Established link <%s> on network plane %c\n",
129 l_ptr->name, l_ptr->b_ptr->net_plane);
132 dbg(" link %x into %x/%x\n", l_ptr, &active[0], &active[1]);
133 active[0] = active[1] = l_ptr;
134 node_established_contact(n_ptr);
137 if (l_ptr->priority < active[0]->priority) {
138 info("New link <%s> becomes standby\n", l_ptr->name);
141 tipc_link_send_duplicate(active[0], l_ptr);
142 if (l_ptr->priority == active[0]->priority) {
146 info("Old link <%s> becomes standby\n", active[0]->name);
147 if (active[1] != active[0])
148 info("Old link <%s> becomes standby\n", active[1]->name);
149 active[0] = active[1] = l_ptr;
153 * node_select_active_links - select active link
156 static void node_select_active_links(struct node *n_ptr)
158 struct link **active = &n_ptr->active_links[0];
160 u32 highest_prio = 0;
162 active[0] = active[1] = NULL;
164 for (i = 0; i < MAX_BEARERS; i++) {
165 struct link *l_ptr = n_ptr->links[i];
167 if (!l_ptr || !tipc_link_is_up(l_ptr) ||
168 (l_ptr->priority < highest_prio))
171 if (l_ptr->priority > highest_prio) {
172 highest_prio = l_ptr->priority;
173 active[0] = active[1] = l_ptr;
181 * tipc_node_link_down - handle loss of link
184 void tipc_node_link_down(struct node *n_ptr, struct link *l_ptr)
186 struct link **active;
188 if (!tipc_link_is_active(l_ptr)) {
189 info("Lost standby link <%s> on network plane %c\n",
190 l_ptr->name, l_ptr->b_ptr->net_plane);
193 info("Lost link <%s> on network plane %c\n",
194 l_ptr->name, l_ptr->b_ptr->net_plane);
196 active = &n_ptr->active_links[0];
197 if (active[0] == l_ptr)
198 active[0] = active[1];
199 if (active[1] == l_ptr)
200 active[1] = active[0];
201 if (active[0] == l_ptr)
202 node_select_active_links(n_ptr);
203 if (tipc_node_is_up(n_ptr))
204 tipc_link_changeover(l_ptr);
206 node_lost_contact(n_ptr);
209 int tipc_node_has_active_links(struct node *n_ptr)
212 ((n_ptr->active_links[0]) || (n_ptr->active_links[1])));
215 int tipc_node_has_redundant_links(struct node *n_ptr)
217 return (tipc_node_has_active_links(n_ptr) &&
218 (n_ptr->active_links[0] != n_ptr->active_links[1]));
221 static int tipc_node_has_active_routes(struct node *n_ptr)
223 return (n_ptr && (n_ptr->last_router >= 0));
226 int tipc_node_is_up(struct node *n_ptr)
228 return (tipc_node_has_active_links(n_ptr) || tipc_node_has_active_routes(n_ptr));
231 struct node *tipc_node_attach_link(struct link *l_ptr)
233 struct node *n_ptr = tipc_node_find(l_ptr->addr);
236 n_ptr = tipc_node_create(l_ptr->addr);
238 u32 bearer_id = l_ptr->b_ptr->identity;
239 char addr_string[16];
241 if (n_ptr->link_cnt >= 2) {
242 char addr_string[16];
244 err("Attempt to create third link to %s\n",
245 addr_string_fill(addr_string, n_ptr->addr));
249 if (!n_ptr->links[bearer_id]) {
250 n_ptr->links[bearer_id] = l_ptr;
251 tipc_net.zones[tipc_zone(l_ptr->addr)]->links++;
255 err("Attempt to establish second link on <%s> to %s \n",
256 l_ptr->b_ptr->publ.name,
257 addr_string_fill(addr_string, l_ptr->addr));
262 void tipc_node_detach_link(struct node *n_ptr, struct link *l_ptr)
264 n_ptr->links[l_ptr->b_ptr->identity] = NULL;
265 tipc_net.zones[tipc_zone(l_ptr->addr)]->links--;
270 * Routing table management - five cases to handle:
272 * 1: A link towards a zone/cluster external node comes up.
273 * => Send a multicast message updating routing tables of all
274 * system nodes within own cluster that the new destination
275 * can be reached via this node.
276 * (node.establishedContact()=>cluster.multicastNewRoute())
278 * 2: A link towards a slave node comes up.
279 * => Send a multicast message updating routing tables of all
280 * system nodes within own cluster that the new destination
281 * can be reached via this node.
282 * (node.establishedContact()=>cluster.multicastNewRoute())
283 * => Send a message to the slave node about existence
284 * of all system nodes within cluster:
285 * (node.establishedContact()=>cluster.sendLocalRoutes())
287 * 3: A new cluster local system node becomes available.
288 * => Send message(s) to this particular node containing
289 * information about all cluster external and slave
290 * nodes which can be reached via this node.
291 * (node.establishedContact()==>network.sendExternalRoutes())
292 * (node.establishedContact()==>network.sendSlaveRoutes())
293 * => Send messages to all directly connected slave nodes
294 * containing information about the existence of the new node
295 * (node.establishedContact()=>cluster.multicastNewRoute())
297 * 4: The link towards a zone/cluster external node or slave
299 * => Send a multcast message updating routing tables of all
300 * nodes within cluster that the new destination can not any
301 * longer be reached via this node.
302 * (node.lostAllLinks()=>cluster.bcastLostRoute())
304 * 5: A cluster local system node becomes unavailable.
305 * => Remove all references to this node from the local
306 * routing tables. Note: This is a completely node
308 * (node.lostAllLinks()=>network.removeAsRouter())
309 * => Send messages to all directly connected slave nodes
310 * containing information about loss of the node
311 * (node.establishedContact()=>cluster.multicastLostRoute())
315 static void node_established_contact(struct node *n_ptr)
317 struct cluster *c_ptr;
319 dbg("node_established_contact:-> %x\n", n_ptr->addr);
320 if (!tipc_node_has_active_routes(n_ptr) && in_own_cluster(n_ptr->addr)) {
321 tipc_k_signal((Handler)tipc_named_node_up, n_ptr->addr);
324 /* Syncronize broadcast acks */
325 n_ptr->bclink.acked = tipc_bclink_get_last_sent();
327 if (is_slave(tipc_own_addr))
329 if (!in_own_cluster(n_ptr->addr)) {
330 /* Usage case 1 (see above) */
331 c_ptr = tipc_cltr_find(tipc_own_addr);
333 c_ptr = tipc_cltr_create(tipc_own_addr);
335 tipc_cltr_bcast_new_route(c_ptr, n_ptr->addr, 1,
340 c_ptr = n_ptr->owner;
341 if (is_slave(n_ptr->addr)) {
342 /* Usage case 2 (see above) */
343 tipc_cltr_bcast_new_route(c_ptr, n_ptr->addr, 1, tipc_max_nodes);
344 tipc_cltr_send_local_routes(c_ptr, n_ptr->addr);
348 if (n_ptr->bclink.supported) {
349 tipc_nmap_add(&tipc_cltr_bcast_nodes, n_ptr->addr);
350 if (n_ptr->addr < tipc_own_addr)
354 /* Case 3 (see above) */
355 tipc_net_send_external_routes(n_ptr->addr);
356 tipc_cltr_send_slave_routes(c_ptr, n_ptr->addr);
357 tipc_cltr_bcast_new_route(c_ptr, n_ptr->addr, LOWEST_SLAVE,
358 tipc_highest_allowed_slave);
361 static void node_lost_contact(struct node *n_ptr)
363 struct cluster *c_ptr;
364 struct node_subscr *ns, *tns;
365 char addr_string[16];
368 /* Clean up broadcast reception remains */
369 n_ptr->bclink.gap_after = n_ptr->bclink.gap_to = 0;
370 while (n_ptr->bclink.deferred_head) {
371 struct sk_buff* buf = n_ptr->bclink.deferred_head;
372 n_ptr->bclink.deferred_head = buf->next;
375 if (n_ptr->bclink.defragm) {
376 buf_discard(n_ptr->bclink.defragm);
377 n_ptr->bclink.defragm = NULL;
379 if (in_own_cluster(n_ptr->addr) && n_ptr->bclink.supported) {
380 tipc_bclink_acknowledge(n_ptr, mod(n_ptr->bclink.acked + 10000));
383 /* Update routing tables */
384 if (is_slave(tipc_own_addr)) {
385 tipc_net_remove_as_router(n_ptr->addr);
387 if (!in_own_cluster(n_ptr->addr)) {
388 /* Case 4 (see above) */
389 c_ptr = tipc_cltr_find(tipc_own_addr);
390 tipc_cltr_bcast_lost_route(c_ptr, n_ptr->addr, 1,
393 /* Case 5 (see above) */
394 c_ptr = tipc_cltr_find(n_ptr->addr);
395 if (is_slave(n_ptr->addr)) {
396 tipc_cltr_bcast_lost_route(c_ptr, n_ptr->addr, 1,
399 if (n_ptr->bclink.supported) {
400 tipc_nmap_remove(&tipc_cltr_bcast_nodes,
402 if (n_ptr->addr < tipc_own_addr)
405 tipc_net_remove_as_router(n_ptr->addr);
406 tipc_cltr_bcast_lost_route(c_ptr, n_ptr->addr,
408 tipc_highest_allowed_slave);
412 if (tipc_node_has_active_routes(n_ptr))
415 info("Lost contact with %s\n",
416 addr_string_fill(addr_string, n_ptr->addr));
418 /* Abort link changeover */
419 for (i = 0; i < MAX_BEARERS; i++) {
420 struct link *l_ptr = n_ptr->links[i];
423 l_ptr->reset_checkpoint = l_ptr->next_in_no;
424 l_ptr->exp_msg_count = 0;
425 tipc_link_reset_fragments(l_ptr);
428 /* Notify subscribers */
429 list_for_each_entry_safe(ns, tns, &n_ptr->nsub, nodesub_list) {
431 list_del_init(&ns->nodesub_list);
432 tipc_k_signal((Handler)ns->handle_node_down,
433 (unsigned long)ns->usr_handle);
438 * tipc_node_select_next_hop - find the next-hop node for a message
440 * Called by when cluster local lookup has failed.
443 struct node *tipc_node_select_next_hop(u32 addr, u32 selector)
448 if (!tipc_addr_domain_valid(addr))
451 /* Look for direct link to destination processsor */
452 n_ptr = tipc_node_find(addr);
453 if (n_ptr && tipc_node_has_active_links(n_ptr))
456 /* Cluster local system nodes *must* have direct links */
457 if (!is_slave(addr) && in_own_cluster(addr))
460 /* Look for cluster local router with direct link to node */
461 router_addr = tipc_node_select_router(n_ptr, selector);
463 return tipc_node_select(router_addr, selector);
465 /* Slave nodes can only be accessed within own cluster via a
466 known router with direct link -- if no router was found,give up */
470 /* Inter zone/cluster -- find any direct link to remote cluster */
471 addr = tipc_addr(tipc_zone(addr), tipc_cluster(addr), 0);
472 n_ptr = tipc_net_select_remote_node(addr, selector);
473 if (n_ptr && tipc_node_has_active_links(n_ptr))
476 /* Last resort -- look for any router to anywhere in remote zone */
477 router_addr = tipc_net_select_router(addr, selector);
479 return tipc_node_select(router_addr, selector);
485 * tipc_node_select_router - select router to reach specified node
487 * Uses a deterministic and fair algorithm for selecting router node.
490 u32 tipc_node_select_router(struct node *n_ptr, u32 ref)
500 if (n_ptr->last_router < 0)
502 ulim = ((n_ptr->last_router + 1) * 32) - 1;
504 /* Start entry must be random */
505 mask = tipc_max_nodes;
511 /* Lookup upwards with wrap-around */
513 if (((n_ptr->routers[r / 32]) >> (r % 32)) & 1)
515 } while (++r <= ulim);
519 if (((n_ptr->routers[r / 32]) >> (r % 32)) & 1)
521 } while (++r < start);
524 assert(r && (r <= ulim));
525 return tipc_addr(own_zone(), own_cluster(), r);
528 void tipc_node_add_router(struct node *n_ptr, u32 router)
530 u32 r_num = tipc_node(router);
532 n_ptr->routers[r_num / 32] =
533 ((1 << (r_num % 32)) | n_ptr->routers[r_num / 32]);
534 n_ptr->last_router = tipc_max_nodes / 32;
535 while ((--n_ptr->last_router >= 0) &&
536 !n_ptr->routers[n_ptr->last_router]);
539 void tipc_node_remove_router(struct node *n_ptr, u32 router)
541 u32 r_num = tipc_node(router);
543 if (n_ptr->last_router < 0)
544 return; /* No routes */
546 n_ptr->routers[r_num / 32] =
547 ((~(1 << (r_num % 32))) & (n_ptr->routers[r_num / 32]));
548 n_ptr->last_router = tipc_max_nodes / 32;
549 while ((--n_ptr->last_router >= 0) &&
550 !n_ptr->routers[n_ptr->last_router]);
552 if (!tipc_node_is_up(n_ptr))
553 node_lost_contact(n_ptr);
557 void node_print(struct print_buf *buf, struct node *n_ptr, char *str)
561 tipc_printf(buf, "\n\n%s", str);
562 for (i = 0; i < MAX_BEARERS; i++) {
563 if (!n_ptr->links[i])
565 tipc_printf(buf, "Links[%u]: %x, ", i, n_ptr->links[i]);
567 tipc_printf(buf, "Active links: [%x,%x]\n",
568 n_ptr->active_links[0], n_ptr->active_links[1]);
572 u32 tipc_available_nodes(const u32 domain)
577 for (n_ptr = tipc_nodes; n_ptr; n_ptr = n_ptr->next) {
578 if (!in_scope(domain, n_ptr->addr))
580 if (tipc_node_is_up(n_ptr))
586 struct sk_buff *tipc_node_get_nodes(const void *req_tlv_area, int req_tlv_space)
591 struct tipc_node_info node_info;
593 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NET_ADDR))
594 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
596 domain = *(u32 *)TLV_DATA(req_tlv_area);
597 domain = ntohl(domain);
598 if (!tipc_addr_domain_valid(domain))
599 return tipc_cfg_reply_error_string(TIPC_CFG_INVALID_VALUE
600 " (network address)");
603 return tipc_cfg_reply_none();
605 /* For now, get space for all other nodes
606 (will need to modify this when slave nodes are supported */
608 buf = tipc_cfg_reply_alloc(TLV_SPACE(sizeof(node_info)) *
609 (tipc_max_nodes - 1));
613 /* Add TLVs for all nodes in scope */
615 for (n_ptr = tipc_nodes; n_ptr; n_ptr = n_ptr->next) {
616 if (!in_scope(domain, n_ptr->addr))
618 node_info.addr = htonl(n_ptr->addr);
619 node_info.up = htonl(tipc_node_is_up(n_ptr));
620 tipc_cfg_append_tlv(buf, TIPC_TLV_NODE_INFO,
621 &node_info, sizeof(node_info));
627 struct sk_buff *tipc_node_get_links(const void *req_tlv_area, int req_tlv_space)
632 struct tipc_link_info link_info;
634 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NET_ADDR))
635 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
637 domain = *(u32 *)TLV_DATA(req_tlv_area);
638 domain = ntohl(domain);
639 if (!tipc_addr_domain_valid(domain))
640 return tipc_cfg_reply_error_string(TIPC_CFG_INVALID_VALUE
641 " (network address)");
644 return tipc_cfg_reply_none();
646 /* For now, get space for 2 links to all other nodes + bcast link
647 (will need to modify this when slave nodes are supported */
649 buf = tipc_cfg_reply_alloc(TLV_SPACE(sizeof(link_info)) *
650 (2 * (tipc_max_nodes - 1) + 1));
654 /* Add TLV for broadcast link */
656 link_info.dest = tipc_own_addr & 0xfffff00;
657 link_info.dest = htonl(link_info.dest);
658 link_info.up = htonl(1);
659 sprintf(link_info.str, tipc_bclink_name);
660 tipc_cfg_append_tlv(buf, TIPC_TLV_LINK_INFO, &link_info, sizeof(link_info));
662 /* Add TLVs for any other links in scope */
664 for (n_ptr = tipc_nodes; n_ptr; n_ptr = n_ptr->next) {
667 if (!in_scope(domain, n_ptr->addr))
669 for (i = 0; i < MAX_BEARERS; i++) {
670 if (!n_ptr->links[i])
672 link_info.dest = htonl(n_ptr->addr);
673 link_info.up = htonl(tipc_link_is_up(n_ptr->links[i]));
674 strcpy(link_info.str, n_ptr->links[i]->name);
675 tipc_cfg_append_tlv(buf, TIPC_TLV_LINK_INFO,
676 &link_info, sizeof(link_info));