2 * net/tipc/node.c: TIPC node management routines
4 * Copyright (c) 2000-2006, Ericsson AB
5 * Copyright (c) 2005-2006, Wind River Systems
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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
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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 tipc_node *n_ptr, char *str);
50 static void node_lost_contact(struct tipc_node *n_ptr);
51 static void node_established_contact(struct tipc_node *n_ptr);
53 struct tipc_node *tipc_nodes = NULL; /* sorted list of nodes within cluster */
55 static DEFINE_SPINLOCK(node_create_lock);
60 * tipc_node_create - create neighboring node
62 * Currently, this routine is called by neighbor discovery code, which holds
63 * net_lock for reading only. We must take node_create_lock to ensure a node
64 * isn't created twice if two different bearers discover the node at the same
65 * time. (It would be preferable to switch to holding net_lock in write mode,
66 * but this is a non-trivial change.)
69 struct tipc_node *tipc_node_create(u32 addr)
71 struct cluster *c_ptr;
72 struct tipc_node *n_ptr;
73 struct tipc_node **curr_node;
75 spin_lock_bh(&node_create_lock);
77 for (n_ptr = tipc_nodes; n_ptr; n_ptr = n_ptr->next) {
78 if (addr < n_ptr->addr)
80 if (addr == n_ptr->addr) {
81 spin_unlock_bh(&node_create_lock);
86 n_ptr = kzalloc(sizeof(*n_ptr),GFP_ATOMIC);
88 spin_unlock_bh(&node_create_lock);
89 warn("Node creation failed, no memory\n");
93 c_ptr = tipc_cltr_find(addr);
95 c_ptr = tipc_cltr_create(addr);
98 spin_unlock_bh(&node_create_lock);
104 spin_lock_init(&n_ptr->lock);
105 INIT_LIST_HEAD(&n_ptr->nsub);
106 n_ptr->owner = c_ptr;
107 tipc_cltr_attach_node(c_ptr, n_ptr);
108 n_ptr->last_router = -1;
110 /* Insert node into ordered list */
111 for (curr_node = &tipc_nodes; *curr_node;
112 curr_node = &(*curr_node)->next) {
113 if (addr < (*curr_node)->addr) {
114 n_ptr->next = *curr_node;
118 (*curr_node) = n_ptr;
119 spin_unlock_bh(&node_create_lock);
123 void tipc_node_delete(struct tipc_node *n_ptr)
129 /* Not needed because links are already deleted via tipc_bearer_stop() */
133 for (l_num = 0; l_num < MAX_BEARERS; l_num++) {
134 link_delete(n_ptr->links[l_num]);
138 dbg("node %x deleted\n", n_ptr->addr);
144 * tipc_node_link_up - handle addition of link
146 * Link becomes active (alone or shared) or standby, depending on its priority.
149 void tipc_node_link_up(struct tipc_node *n_ptr, struct link *l_ptr)
151 struct link **active = &n_ptr->active_links[0];
153 n_ptr->working_links++;
155 info("Established link <%s> on network plane %c\n",
156 l_ptr->name, l_ptr->b_ptr->net_plane);
159 dbg(" link %x into %x/%x\n", l_ptr, &active[0], &active[1]);
160 active[0] = active[1] = l_ptr;
161 node_established_contact(n_ptr);
164 if (l_ptr->priority < active[0]->priority) {
165 info("New link <%s> becomes standby\n", l_ptr->name);
168 tipc_link_send_duplicate(active[0], l_ptr);
169 if (l_ptr->priority == active[0]->priority) {
173 info("Old link <%s> becomes standby\n", active[0]->name);
174 if (active[1] != active[0])
175 info("Old link <%s> becomes standby\n", active[1]->name);
176 active[0] = active[1] = l_ptr;
180 * node_select_active_links - select active link
183 static void node_select_active_links(struct tipc_node *n_ptr)
185 struct link **active = &n_ptr->active_links[0];
187 u32 highest_prio = 0;
189 active[0] = active[1] = NULL;
191 for (i = 0; i < MAX_BEARERS; i++) {
192 struct link *l_ptr = n_ptr->links[i];
194 if (!l_ptr || !tipc_link_is_up(l_ptr) ||
195 (l_ptr->priority < highest_prio))
198 if (l_ptr->priority > highest_prio) {
199 highest_prio = l_ptr->priority;
200 active[0] = active[1] = l_ptr;
208 * tipc_node_link_down - handle loss of link
211 void tipc_node_link_down(struct tipc_node *n_ptr, struct link *l_ptr)
213 struct link **active;
215 n_ptr->working_links--;
217 if (!tipc_link_is_active(l_ptr)) {
218 info("Lost standby link <%s> on network plane %c\n",
219 l_ptr->name, l_ptr->b_ptr->net_plane);
222 info("Lost link <%s> on network plane %c\n",
223 l_ptr->name, l_ptr->b_ptr->net_plane);
225 active = &n_ptr->active_links[0];
226 if (active[0] == l_ptr)
227 active[0] = active[1];
228 if (active[1] == l_ptr)
229 active[1] = active[0];
230 if (active[0] == l_ptr)
231 node_select_active_links(n_ptr);
232 if (tipc_node_is_up(n_ptr))
233 tipc_link_changeover(l_ptr);
235 node_lost_contact(n_ptr);
238 int tipc_node_has_active_links(struct tipc_node *n_ptr)
240 return n_ptr->active_links[0] != NULL;
243 int tipc_node_has_redundant_links(struct tipc_node *n_ptr)
245 return n_ptr->working_links > 1;
248 static int tipc_node_has_active_routes(struct tipc_node *n_ptr)
250 return n_ptr && (n_ptr->last_router >= 0);
253 int tipc_node_is_up(struct tipc_node *n_ptr)
255 return tipc_node_has_active_links(n_ptr) || tipc_node_has_active_routes(n_ptr);
258 struct tipc_node *tipc_node_attach_link(struct link *l_ptr)
260 struct tipc_node *n_ptr = tipc_node_find(l_ptr->addr);
263 n_ptr = tipc_node_create(l_ptr->addr);
265 u32 bearer_id = l_ptr->b_ptr->identity;
266 char addr_string[16];
268 if (n_ptr->link_cnt >= 2) {
269 err("Attempt to create third link to %s\n",
270 tipc_addr_string_fill(addr_string, n_ptr->addr));
274 if (!n_ptr->links[bearer_id]) {
275 n_ptr->links[bearer_id] = l_ptr;
276 tipc_net.zones[tipc_zone(l_ptr->addr)]->links++;
280 err("Attempt to establish second link on <%s> to %s\n",
281 l_ptr->b_ptr->publ.name,
282 tipc_addr_string_fill(addr_string, l_ptr->addr));
287 void tipc_node_detach_link(struct tipc_node *n_ptr, struct link *l_ptr)
289 n_ptr->links[l_ptr->b_ptr->identity] = NULL;
290 tipc_net.zones[tipc_zone(l_ptr->addr)]->links--;
295 * Routing table management - five cases to handle:
297 * 1: A link towards a zone/cluster external node comes up.
298 * => Send a multicast message updating routing tables of all
299 * system nodes within own cluster that the new destination
300 * can be reached via this node.
301 * (node.establishedContact()=>cluster.multicastNewRoute())
303 * 2: A link towards a slave node comes up.
304 * => Send a multicast message updating routing tables of all
305 * system nodes within own cluster that the new destination
306 * can be reached via this node.
307 * (node.establishedContact()=>cluster.multicastNewRoute())
308 * => Send a message to the slave node about existence
309 * of all system nodes within cluster:
310 * (node.establishedContact()=>cluster.sendLocalRoutes())
312 * 3: A new cluster local system node becomes available.
313 * => Send message(s) to this particular node containing
314 * information about all cluster external and slave
315 * nodes which can be reached via this node.
316 * (node.establishedContact()==>network.sendExternalRoutes())
317 * (node.establishedContact()==>network.sendSlaveRoutes())
318 * => Send messages to all directly connected slave nodes
319 * containing information about the existence of the new node
320 * (node.establishedContact()=>cluster.multicastNewRoute())
322 * 4: The link towards a zone/cluster external node or slave
324 * => Send a multcast message updating routing tables of all
325 * nodes within cluster that the new destination can not any
326 * longer be reached via this node.
327 * (node.lostAllLinks()=>cluster.bcastLostRoute())
329 * 5: A cluster local system node becomes unavailable.
330 * => Remove all references to this node from the local
331 * routing tables. Note: This is a completely node
333 * (node.lostAllLinks()=>network.removeAsRouter())
334 * => Send messages to all directly connected slave nodes
335 * containing information about loss of the node
336 * (node.establishedContact()=>cluster.multicastLostRoute())
340 static void node_established_contact(struct tipc_node *n_ptr)
342 struct cluster *c_ptr;
344 dbg("node_established_contact:-> %x\n", n_ptr->addr);
345 if (!tipc_node_has_active_routes(n_ptr) && in_own_cluster(n_ptr->addr)) {
346 tipc_k_signal((Handler)tipc_named_node_up, n_ptr->addr);
349 /* Syncronize broadcast acks */
350 n_ptr->bclink.acked = tipc_bclink_get_last_sent();
352 if (is_slave(tipc_own_addr))
354 if (!in_own_cluster(n_ptr->addr)) {
355 /* Usage case 1 (see above) */
356 c_ptr = tipc_cltr_find(tipc_own_addr);
358 c_ptr = tipc_cltr_create(tipc_own_addr);
360 tipc_cltr_bcast_new_route(c_ptr, n_ptr->addr, 1,
365 c_ptr = n_ptr->owner;
366 if (is_slave(n_ptr->addr)) {
367 /* Usage case 2 (see above) */
368 tipc_cltr_bcast_new_route(c_ptr, n_ptr->addr, 1, tipc_max_nodes);
369 tipc_cltr_send_local_routes(c_ptr, n_ptr->addr);
373 if (n_ptr->bclink.supported) {
374 tipc_nmap_add(&tipc_cltr_bcast_nodes, n_ptr->addr);
375 if (n_ptr->addr < tipc_own_addr)
379 /* Case 3 (see above) */
380 tipc_net_send_external_routes(n_ptr->addr);
381 tipc_cltr_send_slave_routes(c_ptr, n_ptr->addr);
382 tipc_cltr_bcast_new_route(c_ptr, n_ptr->addr, LOWEST_SLAVE,
383 tipc_highest_allowed_slave);
386 static void node_cleanup_finished(unsigned long node_addr)
388 struct tipc_node *n_ptr;
390 read_lock_bh(&tipc_net_lock);
391 n_ptr = tipc_node_find(node_addr);
393 tipc_node_lock(n_ptr);
394 n_ptr->cleanup_required = 0;
395 tipc_node_unlock(n_ptr);
397 read_unlock_bh(&tipc_net_lock);
400 static void node_lost_contact(struct tipc_node *n_ptr)
402 struct cluster *c_ptr;
403 struct tipc_node_subscr *ns, *tns;
404 char addr_string[16];
407 /* Clean up broadcast reception remains */
408 n_ptr->bclink.gap_after = n_ptr->bclink.gap_to = 0;
409 while (n_ptr->bclink.deferred_head) {
410 struct sk_buff* buf = n_ptr->bclink.deferred_head;
411 n_ptr->bclink.deferred_head = buf->next;
414 if (n_ptr->bclink.defragm) {
415 buf_discard(n_ptr->bclink.defragm);
416 n_ptr->bclink.defragm = NULL;
418 if (in_own_cluster(n_ptr->addr) && n_ptr->bclink.supported) {
419 tipc_bclink_acknowledge(n_ptr, mod(n_ptr->bclink.acked + 10000));
422 /* Update routing tables */
423 if (is_slave(tipc_own_addr)) {
424 tipc_net_remove_as_router(n_ptr->addr);
426 if (!in_own_cluster(n_ptr->addr)) {
427 /* Case 4 (see above) */
428 c_ptr = tipc_cltr_find(tipc_own_addr);
429 tipc_cltr_bcast_lost_route(c_ptr, n_ptr->addr, 1,
432 /* Case 5 (see above) */
433 c_ptr = tipc_cltr_find(n_ptr->addr);
434 if (is_slave(n_ptr->addr)) {
435 tipc_cltr_bcast_lost_route(c_ptr, n_ptr->addr, 1,
438 if (n_ptr->bclink.supported) {
439 tipc_nmap_remove(&tipc_cltr_bcast_nodes,
441 if (n_ptr->addr < tipc_own_addr)
444 tipc_net_remove_as_router(n_ptr->addr);
445 tipc_cltr_bcast_lost_route(c_ptr, n_ptr->addr,
447 tipc_highest_allowed_slave);
451 if (tipc_node_has_active_routes(n_ptr))
454 info("Lost contact with %s\n",
455 tipc_addr_string_fill(addr_string, n_ptr->addr));
457 /* Abort link changeover */
458 for (i = 0; i < MAX_BEARERS; i++) {
459 struct link *l_ptr = n_ptr->links[i];
462 l_ptr->reset_checkpoint = l_ptr->next_in_no;
463 l_ptr->exp_msg_count = 0;
464 tipc_link_reset_fragments(l_ptr);
467 /* Notify subscribers */
468 list_for_each_entry_safe(ns, tns, &n_ptr->nsub, nodesub_list) {
470 list_del_init(&ns->nodesub_list);
471 tipc_k_signal((Handler)ns->handle_node_down,
472 (unsigned long)ns->usr_handle);
475 /* Prevent re-contact with node until all cleanup is done */
477 n_ptr->cleanup_required = 1;
478 tipc_k_signal((Handler)node_cleanup_finished, n_ptr->addr);
482 * tipc_node_select_next_hop - find the next-hop node for a message
484 * Called by when cluster local lookup has failed.
487 struct tipc_node *tipc_node_select_next_hop(u32 addr, u32 selector)
489 struct tipc_node *n_ptr;
492 if (!tipc_addr_domain_valid(addr))
495 /* Look for direct link to destination processsor */
496 n_ptr = tipc_node_find(addr);
497 if (n_ptr && tipc_node_has_active_links(n_ptr))
500 /* Cluster local system nodes *must* have direct links */
501 if (!is_slave(addr) && in_own_cluster(addr))
504 /* Look for cluster local router with direct link to node */
505 router_addr = tipc_node_select_router(n_ptr, selector);
507 return tipc_node_select(router_addr, selector);
509 /* Slave nodes can only be accessed within own cluster via a
510 known router with direct link -- if no router was found,give up */
514 /* Inter zone/cluster -- find any direct link to remote cluster */
515 addr = tipc_addr(tipc_zone(addr), tipc_cluster(addr), 0);
516 n_ptr = tipc_net_select_remote_node(addr, selector);
517 if (n_ptr && tipc_node_has_active_links(n_ptr))
520 /* Last resort -- look for any router to anywhere in remote zone */
521 router_addr = tipc_net_select_router(addr, selector);
523 return tipc_node_select(router_addr, selector);
529 * tipc_node_select_router - select router to reach specified node
531 * Uses a deterministic and fair algorithm for selecting router node.
534 u32 tipc_node_select_router(struct tipc_node *n_ptr, u32 ref)
544 if (n_ptr->last_router < 0)
546 ulim = ((n_ptr->last_router + 1) * 32) - 1;
548 /* Start entry must be random */
549 mask = tipc_max_nodes;
555 /* Lookup upwards with wrap-around */
557 if (((n_ptr->routers[r / 32]) >> (r % 32)) & 1)
559 } while (++r <= ulim);
563 if (((n_ptr->routers[r / 32]) >> (r % 32)) & 1)
565 } while (++r < start);
568 assert(r && (r <= ulim));
569 return tipc_addr(own_zone(), own_cluster(), r);
572 void tipc_node_add_router(struct tipc_node *n_ptr, u32 router)
574 u32 r_num = tipc_node(router);
576 n_ptr->routers[r_num / 32] =
577 ((1 << (r_num % 32)) | n_ptr->routers[r_num / 32]);
578 n_ptr->last_router = tipc_max_nodes / 32;
579 while ((--n_ptr->last_router >= 0) &&
580 !n_ptr->routers[n_ptr->last_router]);
583 void tipc_node_remove_router(struct tipc_node *n_ptr, u32 router)
585 u32 r_num = tipc_node(router);
587 if (n_ptr->last_router < 0)
588 return; /* No routes */
590 n_ptr->routers[r_num / 32] =
591 ((~(1 << (r_num % 32))) & (n_ptr->routers[r_num / 32]));
592 n_ptr->last_router = tipc_max_nodes / 32;
593 while ((--n_ptr->last_router >= 0) &&
594 !n_ptr->routers[n_ptr->last_router]);
596 if (!tipc_node_is_up(n_ptr))
597 node_lost_contact(n_ptr);
601 void node_print(struct print_buf *buf, struct tipc_node *n_ptr, char *str)
605 tipc_printf(buf, "\n\n%s", str);
606 for (i = 0; i < MAX_BEARERS; i++) {
607 if (!n_ptr->links[i])
609 tipc_printf(buf, "Links[%u]: %x, ", i, n_ptr->links[i]);
611 tipc_printf(buf, "Active links: [%x,%x]\n",
612 n_ptr->active_links[0], n_ptr->active_links[1]);
616 u32 tipc_available_nodes(const u32 domain)
618 struct tipc_node *n_ptr;
621 read_lock_bh(&tipc_net_lock);
622 for (n_ptr = tipc_nodes; n_ptr; n_ptr = n_ptr->next) {
623 if (!tipc_in_scope(domain, n_ptr->addr))
625 if (tipc_node_is_up(n_ptr))
628 read_unlock_bh(&tipc_net_lock);
632 struct sk_buff *tipc_node_get_nodes(const void *req_tlv_area, int req_tlv_space)
636 struct tipc_node *n_ptr;
637 struct tipc_node_info node_info;
640 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NET_ADDR))
641 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
643 domain = ntohl(*(__be32 *)TLV_DATA(req_tlv_area));
644 if (!tipc_addr_domain_valid(domain))
645 return tipc_cfg_reply_error_string(TIPC_CFG_INVALID_VALUE
646 " (network address)");
648 read_lock_bh(&tipc_net_lock);
650 read_unlock_bh(&tipc_net_lock);
651 return tipc_cfg_reply_none();
654 /* For now, get space for all other nodes
655 (will need to modify this when slave nodes are supported */
657 payload_size = TLV_SPACE(sizeof(node_info)) * (tipc_max_nodes - 1);
658 if (payload_size > 32768u) {
659 read_unlock_bh(&tipc_net_lock);
660 return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
661 " (too many nodes)");
663 buf = tipc_cfg_reply_alloc(payload_size);
665 read_unlock_bh(&tipc_net_lock);
669 /* Add TLVs for all nodes in scope */
671 for (n_ptr = tipc_nodes; n_ptr; n_ptr = n_ptr->next) {
672 if (!tipc_in_scope(domain, n_ptr->addr))
674 node_info.addr = htonl(n_ptr->addr);
675 node_info.up = htonl(tipc_node_is_up(n_ptr));
676 tipc_cfg_append_tlv(buf, TIPC_TLV_NODE_INFO,
677 &node_info, sizeof(node_info));
680 read_unlock_bh(&tipc_net_lock);
684 struct sk_buff *tipc_node_get_links(const void *req_tlv_area, int req_tlv_space)
688 struct tipc_node *n_ptr;
689 struct tipc_link_info link_info;
692 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NET_ADDR))
693 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
695 domain = ntohl(*(__be32 *)TLV_DATA(req_tlv_area));
696 if (!tipc_addr_domain_valid(domain))
697 return tipc_cfg_reply_error_string(TIPC_CFG_INVALID_VALUE
698 " (network address)");
700 if (tipc_mode != TIPC_NET_MODE)
701 return tipc_cfg_reply_none();
703 read_lock_bh(&tipc_net_lock);
705 /* Get space for all unicast links + multicast link */
707 payload_size = TLV_SPACE(sizeof(link_info)) *
708 (tipc_net.zones[tipc_zone(tipc_own_addr)]->links + 1);
709 if (payload_size > 32768u) {
710 read_unlock_bh(&tipc_net_lock);
711 return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
712 " (too many links)");
714 buf = tipc_cfg_reply_alloc(payload_size);
716 read_unlock_bh(&tipc_net_lock);
720 /* Add TLV for broadcast link */
722 link_info.dest = htonl(tipc_own_addr & 0xfffff00);
723 link_info.up = htonl(1);
724 strlcpy(link_info.str, tipc_bclink_name, TIPC_MAX_LINK_NAME);
725 tipc_cfg_append_tlv(buf, TIPC_TLV_LINK_INFO, &link_info, sizeof(link_info));
727 /* Add TLVs for any other links in scope */
729 for (n_ptr = tipc_nodes; n_ptr; n_ptr = n_ptr->next) {
732 if (!tipc_in_scope(domain, n_ptr->addr))
734 tipc_node_lock(n_ptr);
735 for (i = 0; i < MAX_BEARERS; i++) {
736 if (!n_ptr->links[i])
738 link_info.dest = htonl(n_ptr->addr);
739 link_info.up = htonl(tipc_link_is_up(n_ptr->links[i]));
740 strcpy(link_info.str, n_ptr->links[i]->name);
741 tipc_cfg_append_tlv(buf, TIPC_TLV_LINK_INFO,
742 &link_info, sizeof(link_info));
744 tipc_node_unlock(n_ptr);
747 read_unlock_bh(&tipc_net_lock);