2 * net/tipc/node.c: TIPC node management routines
4 * Copyright (c) 2000-2006, 2012 Ericsson AB
5 * Copyright (c) 2005-2006, 2010-2014, Wind River Systems
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40 #include "name_distr.h"
42 #define NODE_HTABLE_SIZE 512
44 static void node_lost_contact(struct tipc_node *n_ptr);
45 static void node_established_contact(struct tipc_node *n_ptr);
47 static struct hlist_head node_htable[NODE_HTABLE_SIZE];
48 LIST_HEAD(tipc_node_list);
49 static u32 tipc_num_nodes;
50 static u32 tipc_num_links;
51 static DEFINE_SPINLOCK(node_list_lock);
54 * A trivial power-of-two bitmask technique is used for speed, since this
55 * operation is done for every incoming TIPC packet. The number of hash table
56 * entries has been chosen so that no hash chain exceeds 8 nodes and will
57 * usually be much smaller (typically only a single node).
59 static unsigned int tipc_hashfn(u32 addr)
61 return addr & (NODE_HTABLE_SIZE - 1);
65 * tipc_node_find - locate specified node object, if it exists
67 struct tipc_node *tipc_node_find(u32 addr)
69 struct tipc_node *node;
71 if (unlikely(!in_own_cluster_exact(addr)))
75 hlist_for_each_entry_rcu(node, &node_htable[tipc_hashfn(addr)], hash) {
76 if (node->addr == addr) {
85 struct tipc_node *tipc_node_create(u32 addr)
87 struct tipc_node *n_ptr, *temp_node;
89 spin_lock_bh(&node_list_lock);
91 n_ptr = kzalloc(sizeof(*n_ptr), GFP_ATOMIC);
93 spin_unlock_bh(&node_list_lock);
94 pr_warn("Node creation failed, no memory\n");
99 spin_lock_init(&n_ptr->lock);
100 INIT_HLIST_NODE(&n_ptr->hash);
101 INIT_LIST_HEAD(&n_ptr->list);
102 INIT_LIST_HEAD(&n_ptr->nsub);
104 hlist_add_head_rcu(&n_ptr->hash, &node_htable[tipc_hashfn(addr)]);
106 list_for_each_entry_rcu(temp_node, &tipc_node_list, list) {
107 if (n_ptr->addr < temp_node->addr)
110 list_add_tail_rcu(&n_ptr->list, &temp_node->list);
111 n_ptr->flags = TIPC_NODE_DOWN;
112 n_ptr->signature = INVALID_NODE_SIG;
116 spin_unlock_bh(&node_list_lock);
120 static void tipc_node_delete(struct tipc_node *n_ptr)
122 list_del_rcu(&n_ptr->list);
123 hlist_del_rcu(&n_ptr->hash);
124 kfree_rcu(n_ptr, rcu);
129 void tipc_node_stop(void)
131 struct tipc_node *node, *t_node;
133 spin_lock_bh(&node_list_lock);
134 list_for_each_entry_safe(node, t_node, &tipc_node_list, list)
135 tipc_node_delete(node);
136 spin_unlock_bh(&node_list_lock);
140 * tipc_node_link_up - handle addition of link
142 * Link becomes active (alone or shared) or standby, depending on its priority.
144 void tipc_node_link_up(struct tipc_node *n_ptr, struct tipc_link *l_ptr)
146 struct tipc_link **active = &n_ptr->active_links[0];
147 u32 addr = n_ptr->addr;
149 n_ptr->working_links++;
150 tipc_nametbl_publish(TIPC_LINK_STATE, addr, addr, TIPC_NODE_SCOPE,
151 l_ptr->bearer_id, addr);
152 pr_info("Established link <%s> on network plane %c\n",
153 l_ptr->name, l_ptr->net_plane);
156 active[0] = active[1] = l_ptr;
157 node_established_contact(n_ptr);
160 if (l_ptr->priority < active[0]->priority) {
161 pr_info("New link <%s> becomes standby\n", l_ptr->name);
164 tipc_link_dup_queue_xmit(active[0], l_ptr);
165 if (l_ptr->priority == active[0]->priority) {
169 pr_info("Old link <%s> becomes standby\n", active[0]->name);
170 if (active[1] != active[0])
171 pr_info("Old link <%s> becomes standby\n", active[1]->name);
172 active[0] = active[1] = l_ptr;
176 * node_select_active_links - select active link
178 static void node_select_active_links(struct tipc_node *n_ptr)
180 struct tipc_link **active = &n_ptr->active_links[0];
182 u32 highest_prio = 0;
184 active[0] = active[1] = NULL;
186 for (i = 0; i < MAX_BEARERS; i++) {
187 struct tipc_link *l_ptr = n_ptr->links[i];
189 if (!l_ptr || !tipc_link_is_up(l_ptr) ||
190 (l_ptr->priority < highest_prio))
193 if (l_ptr->priority > highest_prio) {
194 highest_prio = l_ptr->priority;
195 active[0] = active[1] = l_ptr;
203 * tipc_node_link_down - handle loss of link
205 void tipc_node_link_down(struct tipc_node *n_ptr, struct tipc_link *l_ptr)
207 struct tipc_link **active;
208 u32 addr = n_ptr->addr;
210 n_ptr->working_links--;
211 tipc_nametbl_withdraw(TIPC_LINK_STATE, addr, l_ptr->bearer_id, addr);
213 if (!tipc_link_is_active(l_ptr)) {
214 pr_info("Lost standby link <%s> on network plane %c\n",
215 l_ptr->name, l_ptr->net_plane);
218 pr_info("Lost link <%s> on network plane %c\n",
219 l_ptr->name, l_ptr->net_plane);
221 active = &n_ptr->active_links[0];
222 if (active[0] == l_ptr)
223 active[0] = active[1];
224 if (active[1] == l_ptr)
225 active[1] = active[0];
226 if (active[0] == l_ptr)
227 node_select_active_links(n_ptr);
228 if (tipc_node_is_up(n_ptr))
229 tipc_link_failover_send_queue(l_ptr);
231 node_lost_contact(n_ptr);
234 int tipc_node_active_links(struct tipc_node *n_ptr)
236 return n_ptr->active_links[0] != NULL;
239 int tipc_node_is_up(struct tipc_node *n_ptr)
241 return tipc_node_active_links(n_ptr);
244 void tipc_node_attach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr)
246 n_ptr->links[l_ptr->bearer_id] = l_ptr;
247 spin_lock_bh(&node_list_lock);
249 spin_unlock_bh(&node_list_lock);
253 void tipc_node_detach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr)
257 for (i = 0; i < MAX_BEARERS; i++) {
258 if (l_ptr != n_ptr->links[i])
260 n_ptr->links[i] = NULL;
261 spin_lock_bh(&node_list_lock);
263 spin_unlock_bh(&node_list_lock);
268 static void node_established_contact(struct tipc_node *n_ptr)
270 tipc_k_signal((Handler)tipc_named_node_up, n_ptr->addr);
271 n_ptr->bclink.oos_state = 0;
272 n_ptr->bclink.acked = tipc_bclink_get_last_sent();
273 tipc_bclink_add_node(n_ptr->addr);
276 static void node_lost_contact(struct tipc_node *n_ptr)
278 char addr_string[16];
281 pr_info("Lost contact with %s\n",
282 tipc_addr_string_fill(addr_string, n_ptr->addr));
284 /* Flush broadcast link info associated with lost node */
285 if (n_ptr->bclink.recv_permitted) {
286 kfree_skb_list(n_ptr->bclink.deferred_head);
287 n_ptr->bclink.deferred_size = 0;
289 if (n_ptr->bclink.reasm_head) {
290 kfree_skb(n_ptr->bclink.reasm_head);
291 n_ptr->bclink.reasm_head = NULL;
292 n_ptr->bclink.reasm_tail = NULL;
295 tipc_bclink_remove_node(n_ptr->addr);
296 tipc_bclink_acknowledge(n_ptr, INVALID_LINK_SEQ);
298 n_ptr->bclink.recv_permitted = false;
301 /* Abort link changeover */
302 for (i = 0; i < MAX_BEARERS; i++) {
303 struct tipc_link *l_ptr = n_ptr->links[i];
306 l_ptr->reset_checkpoint = l_ptr->next_in_no;
307 l_ptr->exp_msg_count = 0;
308 tipc_link_reset_fragments(l_ptr);
311 /* Notify subscribers and prevent re-contact with node until
314 n_ptr->flags = TIPC_NODE_DOWN | TIPC_NODE_LOST;
317 struct sk_buff *tipc_node_get_nodes(const void *req_tlv_area, int req_tlv_space)
321 struct tipc_node *n_ptr;
322 struct tipc_node_info node_info;
325 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NET_ADDR))
326 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
328 domain = ntohl(*(__be32 *)TLV_DATA(req_tlv_area));
329 if (!tipc_addr_domain_valid(domain))
330 return tipc_cfg_reply_error_string(TIPC_CFG_INVALID_VALUE
331 " (network address)");
333 spin_lock_bh(&node_list_lock);
334 if (!tipc_num_nodes) {
335 spin_unlock_bh(&node_list_lock);
336 return tipc_cfg_reply_none();
339 /* For now, get space for all other nodes */
340 payload_size = TLV_SPACE(sizeof(node_info)) * tipc_num_nodes;
341 if (payload_size > 32768u) {
342 spin_unlock_bh(&node_list_lock);
343 return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
344 " (too many nodes)");
346 spin_unlock_bh(&node_list_lock);
348 buf = tipc_cfg_reply_alloc(payload_size);
352 /* Add TLVs for all nodes in scope */
354 list_for_each_entry_rcu(n_ptr, &tipc_node_list, list) {
355 if (!tipc_in_scope(domain, n_ptr->addr))
357 node_info.addr = htonl(n_ptr->addr);
358 node_info.up = htonl(tipc_node_is_up(n_ptr));
359 tipc_cfg_append_tlv(buf, TIPC_TLV_NODE_INFO,
360 &node_info, sizeof(node_info));
366 struct sk_buff *tipc_node_get_links(const void *req_tlv_area, int req_tlv_space)
370 struct tipc_node *n_ptr;
371 struct tipc_link_info link_info;
374 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NET_ADDR))
375 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
377 domain = ntohl(*(__be32 *)TLV_DATA(req_tlv_area));
378 if (!tipc_addr_domain_valid(domain))
379 return tipc_cfg_reply_error_string(TIPC_CFG_INVALID_VALUE
380 " (network address)");
383 return tipc_cfg_reply_none();
385 spin_lock_bh(&node_list_lock);
386 /* Get space for all unicast links + broadcast link */
387 payload_size = TLV_SPACE((sizeof(link_info)) * (tipc_num_links + 1));
388 if (payload_size > 32768u) {
389 spin_unlock_bh(&node_list_lock);
390 return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
391 " (too many links)");
393 spin_unlock_bh(&node_list_lock);
395 buf = tipc_cfg_reply_alloc(payload_size);
399 /* Add TLV for broadcast link */
400 link_info.dest = htonl(tipc_cluster_mask(tipc_own_addr));
401 link_info.up = htonl(1);
402 strlcpy(link_info.str, tipc_bclink_name, TIPC_MAX_LINK_NAME);
403 tipc_cfg_append_tlv(buf, TIPC_TLV_LINK_INFO, &link_info, sizeof(link_info));
405 /* Add TLVs for any other links in scope */
407 list_for_each_entry_rcu(n_ptr, &tipc_node_list, list) {
410 if (!tipc_in_scope(domain, n_ptr->addr))
412 tipc_node_lock(n_ptr);
413 for (i = 0; i < MAX_BEARERS; i++) {
414 if (!n_ptr->links[i])
416 link_info.dest = htonl(n_ptr->addr);
417 link_info.up = htonl(tipc_link_is_up(n_ptr->links[i]));
418 strcpy(link_info.str, n_ptr->links[i]->name);
419 tipc_cfg_append_tlv(buf, TIPC_TLV_LINK_INFO,
420 &link_info, sizeof(link_info));
422 tipc_node_unlock(n_ptr);
429 * tipc_node_get_linkname - get the name of a link
431 * @bearer_id: id of the bearer
432 * @node: peer node address
433 * @linkname: link name output buffer
435 * Returns 0 on success
437 int tipc_node_get_linkname(u32 bearer_id, u32 addr, char *linkname, size_t len)
439 struct tipc_link *link;
440 struct tipc_node *node = tipc_node_find(addr);
442 if ((bearer_id >= MAX_BEARERS) || !node)
444 tipc_node_lock(node);
445 link = node->links[bearer_id];
447 strncpy(linkname, link->name, len);
448 tipc_node_unlock(node);
451 tipc_node_unlock(node);
455 void tipc_node_unlock(struct tipc_node *node)
457 LIST_HEAD(nsub_list);
459 if (likely(!node->flags)) {
460 spin_unlock_bh(&node->lock);
464 if (node->flags & TIPC_NODE_LOST) {
465 list_replace_init(&node->nsub, &nsub_list);
466 node->flags &= ~TIPC_NODE_LOST;
468 spin_unlock_bh(&node->lock);
470 if (!list_empty(&nsub_list))
471 tipc_nodesub_notify(&nsub_list);