2 * net/tipc/node.c: TIPC node management routines
4 * Copyright (c) 2000-2006, 2012-2015, Ericsson AB
5 * Copyright (c) 2005-2006, 2010-2014, Wind River Systems
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21 * GNU General Public License ("GPL") version 2 as published by the Free
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40 #include "name_distr.h"
44 static void node_lost_contact(struct tipc_node *n_ptr);
45 static void node_established_contact(struct tipc_node *n_ptr);
46 static void tipc_node_delete(struct tipc_node *node);
48 struct tipc_sock_conn {
52 struct list_head list;
55 static const struct nla_policy tipc_nl_node_policy[TIPC_NLA_NODE_MAX + 1] = {
56 [TIPC_NLA_NODE_UNSPEC] = { .type = NLA_UNSPEC },
57 [TIPC_NLA_NODE_ADDR] = { .type = NLA_U32 },
58 [TIPC_NLA_NODE_UP] = { .type = NLA_FLAG }
62 * A trivial power-of-two bitmask technique is used for speed, since this
63 * operation is done for every incoming TIPC packet. The number of hash table
64 * entries has been chosen so that no hash chain exceeds 8 nodes and will
65 * usually be much smaller (typically only a single node).
67 static unsigned int tipc_hashfn(u32 addr)
69 return addr & (NODE_HTABLE_SIZE - 1);
72 static void tipc_node_kref_release(struct kref *kref)
74 struct tipc_node *node = container_of(kref, struct tipc_node, kref);
76 tipc_node_delete(node);
79 void tipc_node_put(struct tipc_node *node)
81 kref_put(&node->kref, tipc_node_kref_release);
84 static void tipc_node_get(struct tipc_node *node)
86 kref_get(&node->kref);
90 * tipc_node_find - locate specified node object, if it exists
92 struct tipc_node *tipc_node_find(struct net *net, u32 addr)
94 struct tipc_net *tn = net_generic(net, tipc_net_id);
95 struct tipc_node *node;
97 if (unlikely(!in_own_cluster_exact(net, addr)))
101 hlist_for_each_entry_rcu(node, &tn->node_htable[tipc_hashfn(addr)],
103 if (node->addr == addr) {
113 struct tipc_node *tipc_node_create(struct net *net, u32 addr)
115 struct tipc_net *tn = net_generic(net, tipc_net_id);
116 struct tipc_node *n_ptr, *temp_node;
118 spin_lock_bh(&tn->node_list_lock);
119 n_ptr = tipc_node_find(net, addr);
122 n_ptr = kzalloc(sizeof(*n_ptr), GFP_ATOMIC);
124 pr_warn("Node creation failed, no memory\n");
129 kref_init(&n_ptr->kref);
130 spin_lock_init(&n_ptr->lock);
131 INIT_HLIST_NODE(&n_ptr->hash);
132 INIT_LIST_HEAD(&n_ptr->list);
133 INIT_LIST_HEAD(&n_ptr->publ_list);
134 INIT_LIST_HEAD(&n_ptr->conn_sks);
135 skb_queue_head_init(&n_ptr->bclink.namedq);
136 __skb_queue_head_init(&n_ptr->bclink.deferdq);
137 hlist_add_head_rcu(&n_ptr->hash, &tn->node_htable[tipc_hashfn(addr)]);
138 list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
139 if (n_ptr->addr < temp_node->addr)
142 list_add_tail_rcu(&n_ptr->list, &temp_node->list);
143 n_ptr->action_flags = TIPC_WAIT_PEER_LINKS_DOWN;
144 n_ptr->signature = INVALID_NODE_SIG;
145 n_ptr->active_links[0] = INVALID_BEARER_ID;
146 n_ptr->active_links[1] = INVALID_BEARER_ID;
147 tipc_node_get(n_ptr);
149 spin_unlock_bh(&tn->node_list_lock);
153 static void tipc_node_delete(struct tipc_node *node)
155 list_del_rcu(&node->list);
156 hlist_del_rcu(&node->hash);
157 kfree_rcu(node, rcu);
160 void tipc_node_stop(struct net *net)
162 struct tipc_net *tn = net_generic(net, tipc_net_id);
163 struct tipc_node *node, *t_node;
165 spin_lock_bh(&tn->node_list_lock);
166 list_for_each_entry_safe(node, t_node, &tn->node_list, list)
168 spin_unlock_bh(&tn->node_list_lock);
171 int tipc_node_add_conn(struct net *net, u32 dnode, u32 port, u32 peer_port)
173 struct tipc_node *node;
174 struct tipc_sock_conn *conn;
177 if (in_own_node(net, dnode))
180 node = tipc_node_find(net, dnode);
182 pr_warn("Connecting sock to node 0x%x failed\n", dnode);
183 return -EHOSTUNREACH;
185 conn = kmalloc(sizeof(*conn), GFP_ATOMIC);
190 conn->peer_node = dnode;
192 conn->peer_port = peer_port;
194 tipc_node_lock(node);
195 list_add_tail(&conn->list, &node->conn_sks);
196 tipc_node_unlock(node);
202 void tipc_node_remove_conn(struct net *net, u32 dnode, u32 port)
204 struct tipc_node *node;
205 struct tipc_sock_conn *conn, *safe;
207 if (in_own_node(net, dnode))
210 node = tipc_node_find(net, dnode);
214 tipc_node_lock(node);
215 list_for_each_entry_safe(conn, safe, &node->conn_sks, list) {
216 if (port != conn->port)
218 list_del(&conn->list);
221 tipc_node_unlock(node);
226 * tipc_node_link_up - handle addition of link
228 * Link becomes active (alone or shared) or standby, depending on its priority.
230 void tipc_node_link_up(struct tipc_node *n, int bearer_id)
232 int *slot0 = &n->active_links[0];
233 int *slot1 = &n->active_links[1];
234 struct tipc_link_entry *links = n->links;
235 struct tipc_link *l = n->links[bearer_id].link;
237 /* Leave room for tunnel header when returning 'mtu' to users: */
238 links[bearer_id].mtu = l->mtu - INT_H_SIZE;
241 n->action_flags |= TIPC_NOTIFY_LINK_UP;
242 n->link_id = l->peer_bearer_id << 16 | l->bearer_id;
244 pr_debug("Established link <%s> on network plane %c\n",
245 l->name, l->net_plane);
247 /* No active links ? => take both active slots */
251 node_established_contact(n);
255 /* Lower prio than current active ? => no slot */
256 if (l->priority < links[*slot0].link->priority) {
257 pr_debug("New link <%s> becomes standby\n", l->name);
260 tipc_link_dup_queue_xmit(links[*slot0].link, l);
262 /* Same prio as current active ? => take one slot */
263 if (l->priority == links[*slot0].link->priority) {
268 /* Higher prio than current active => take both active slots */
269 pr_debug("Old link <%s> now standby\n", links[*slot0].link->name);
275 * tipc_node_link_down - handle loss of link
277 void tipc_node_link_down(struct tipc_node *n, int bearer_id)
279 int *slot0 = &n->active_links[0];
280 int *slot1 = &n->active_links[1];
282 struct tipc_link *l, *_l;
284 l = n->links[bearer_id].link;
286 n->action_flags |= TIPC_NOTIFY_LINK_DOWN;
287 n->link_id = l->peer_bearer_id << 16 | l->bearer_id;
289 pr_debug("Lost link <%s> on network plane %c\n",
290 l->name, l->net_plane);
292 /* Select new active link if any available */
293 *slot0 = INVALID_BEARER_ID;
294 *slot1 = INVALID_BEARER_ID;
295 for (i = 0; i < MAX_BEARERS; i++) {
296 _l = n->links[i].link;
297 if (!_l || !tipc_link_is_up(_l))
299 if (_l->priority < highest)
301 if (_l->priority > highest) {
302 highest = _l->priority;
309 if (tipc_node_is_up(n))
310 tipc_link_failover_send_queue(l);
312 node_lost_contact(n);
315 bool tipc_node_is_up(struct tipc_node *n)
317 return n->active_links[0] != INVALID_BEARER_ID;
320 void tipc_node_check_dest(struct tipc_node *n, struct tipc_bearer *b,
321 bool *link_up, bool *addr_match,
322 struct tipc_media_addr *maddr)
324 struct tipc_link *l = n->links[b->identity].link;
325 struct tipc_media_addr *curr = &n->links[b->identity].maddr;
327 *link_up = l && tipc_link_is_up(l);
328 *addr_match = l && !memcmp(curr, maddr, sizeof(*maddr));
331 bool tipc_node_update_dest(struct tipc_node *n, struct tipc_bearer *b,
332 struct tipc_media_addr *maddr)
334 struct tipc_link *l = n->links[b->identity].link;
335 struct tipc_media_addr *curr = &n->links[b->identity].maddr;
336 struct sk_buff_head *inputq = &n->links[b->identity].inputq;
339 l = tipc_link_create(n, b, maddr, inputq, &n->bclink.namedq);
342 memcpy(&l->media_addr, maddr, sizeof(*maddr));
343 memcpy(curr, maddr, sizeof(*maddr));
348 void tipc_node_attach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr)
350 n_ptr->links[l_ptr->bearer_id].link = l_ptr;
354 void tipc_node_detach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr)
358 for (i = 0; i < MAX_BEARERS; i++) {
359 if (l_ptr != n_ptr->links[i].link)
361 n_ptr->links[i].link = NULL;
366 static void node_established_contact(struct tipc_node *n_ptr)
368 n_ptr->action_flags |= TIPC_NOTIFY_NODE_UP;
369 n_ptr->bclink.oos_state = 0;
370 n_ptr->bclink.acked = tipc_bclink_get_last_sent(n_ptr->net);
371 tipc_bclink_add_node(n_ptr->net, n_ptr->addr);
374 static void node_lost_contact(struct tipc_node *n_ptr)
376 char addr_string[16];
377 struct tipc_sock_conn *conn, *safe;
378 struct list_head *conns = &n_ptr->conn_sks;
380 struct tipc_net *tn = net_generic(n_ptr->net, tipc_net_id);
383 pr_debug("Lost contact with %s\n",
384 tipc_addr_string_fill(addr_string, n_ptr->addr));
386 /* Flush broadcast link info associated with lost node */
387 if (n_ptr->bclink.recv_permitted) {
388 __skb_queue_purge(&n_ptr->bclink.deferdq);
390 if (n_ptr->bclink.reasm_buf) {
391 kfree_skb(n_ptr->bclink.reasm_buf);
392 n_ptr->bclink.reasm_buf = NULL;
395 tipc_bclink_remove_node(n_ptr->net, n_ptr->addr);
396 tipc_bclink_acknowledge(n_ptr, INVALID_LINK_SEQ);
398 n_ptr->bclink.recv_permitted = false;
401 /* Abort any ongoing link failover */
402 for (i = 0; i < MAX_BEARERS; i++) {
403 struct tipc_link *l_ptr = n_ptr->links[i].link;
406 l_ptr->flags &= ~LINK_FAILINGOVER;
407 l_ptr->failover_checkpt = 0;
408 l_ptr->failover_pkts = 0;
409 kfree_skb(l_ptr->failover_skb);
410 l_ptr->failover_skb = NULL;
411 tipc_link_reset_fragments(l_ptr);
414 n_ptr->action_flags &= ~TIPC_WAIT_OWN_LINKS_DOWN;
416 /* Prevent re-contact with node until cleanup is done */
417 n_ptr->action_flags |= TIPC_WAIT_PEER_LINKS_DOWN;
419 /* Notify publications from this node */
420 n_ptr->action_flags |= TIPC_NOTIFY_NODE_DOWN;
422 /* Notify sockets connected to node */
423 list_for_each_entry_safe(conn, safe, conns, list) {
424 skb = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE, TIPC_CONN_MSG,
425 SHORT_H_SIZE, 0, tn->own_addr,
426 conn->peer_node, conn->port,
427 conn->peer_port, TIPC_ERR_NO_NODE);
429 skb_queue_tail(n_ptr->inputq, skb);
430 n_ptr->action_flags |= TIPC_MSG_EVT;
432 list_del(&conn->list);
438 * tipc_node_get_linkname - get the name of a link
440 * @bearer_id: id of the bearer
441 * @node: peer node address
442 * @linkname: link name output buffer
444 * Returns 0 on success
446 int tipc_node_get_linkname(struct net *net, u32 bearer_id, u32 addr,
447 char *linkname, size_t len)
449 struct tipc_link *link;
451 struct tipc_node *node = tipc_node_find(net, addr);
456 if (bearer_id >= MAX_BEARERS)
459 tipc_node_lock(node);
460 link = node->links[bearer_id].link;
462 strncpy(linkname, link->name, len);
466 tipc_node_unlock(node);
471 void tipc_node_unlock(struct tipc_node *node)
473 struct net *net = node->net;
475 u32 flags = node->action_flags;
477 struct list_head *publ_list;
478 struct sk_buff_head *inputq = node->inputq;
479 struct sk_buff_head *namedq;
481 if (likely(!flags || (flags == TIPC_MSG_EVT))) {
482 node->action_flags = 0;
483 spin_unlock_bh(&node->lock);
484 if (flags == TIPC_MSG_EVT)
485 tipc_sk_rcv(net, inputq);
490 link_id = node->link_id;
491 namedq = node->namedq;
492 publ_list = &node->publ_list;
494 node->action_flags &= ~(TIPC_MSG_EVT |
495 TIPC_NOTIFY_NODE_DOWN | TIPC_NOTIFY_NODE_UP |
496 TIPC_NOTIFY_LINK_DOWN | TIPC_NOTIFY_LINK_UP |
497 TIPC_WAKEUP_BCAST_USERS | TIPC_BCAST_MSG_EVT |
498 TIPC_NAMED_MSG_EVT | TIPC_BCAST_RESET);
500 spin_unlock_bh(&node->lock);
502 if (flags & TIPC_NOTIFY_NODE_DOWN)
503 tipc_publ_notify(net, publ_list, addr);
505 if (flags & TIPC_WAKEUP_BCAST_USERS)
506 tipc_bclink_wakeup_users(net);
508 if (flags & TIPC_NOTIFY_NODE_UP)
509 tipc_named_node_up(net, addr);
511 if (flags & TIPC_NOTIFY_LINK_UP)
512 tipc_nametbl_publish(net, TIPC_LINK_STATE, addr, addr,
513 TIPC_NODE_SCOPE, link_id, addr);
515 if (flags & TIPC_NOTIFY_LINK_DOWN)
516 tipc_nametbl_withdraw(net, TIPC_LINK_STATE, addr,
519 if (flags & TIPC_MSG_EVT)
520 tipc_sk_rcv(net, inputq);
522 if (flags & TIPC_NAMED_MSG_EVT)
523 tipc_named_rcv(net, namedq);
525 if (flags & TIPC_BCAST_MSG_EVT)
526 tipc_bclink_input(net);
528 if (flags & TIPC_BCAST_RESET)
529 tipc_link_reset_all(node);
532 /* Caller should hold node lock for the passed node */
533 static int __tipc_nl_add_node(struct tipc_nl_msg *msg, struct tipc_node *node)
536 struct nlattr *attrs;
538 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
539 NLM_F_MULTI, TIPC_NL_NODE_GET);
543 attrs = nla_nest_start(msg->skb, TIPC_NLA_NODE);
547 if (nla_put_u32(msg->skb, TIPC_NLA_NODE_ADDR, node->addr))
549 if (tipc_node_is_up(node))
550 if (nla_put_flag(msg->skb, TIPC_NLA_NODE_UP))
553 nla_nest_end(msg->skb, attrs);
554 genlmsg_end(msg->skb, hdr);
559 nla_nest_cancel(msg->skb, attrs);
561 genlmsg_cancel(msg->skb, hdr);
566 static struct tipc_link *tipc_node_select_link(struct tipc_node *n, int sel,
568 struct tipc_media_addr **maddr)
570 int id = n->active_links[sel & 1];
572 if (unlikely(id < 0))
576 *maddr = &n->links[id].maddr;
577 return n->links[id].link;
581 * tipc_node_xmit() is the general link level function for message sending
582 * @net: the applicable net namespace
583 * @list: chain of buffers containing message
584 * @dnode: address of destination node
585 * @selector: a number used for deterministic link selection
586 * Consumes the buffer chain, except when returning -ELINKCONG
587 * Returns 0 if success, otherwise errno: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE
589 int tipc_node_xmit(struct net *net, struct sk_buff_head *list,
590 u32 dnode, int selector)
592 struct tipc_link *l = NULL;
594 struct sk_buff_head xmitq;
595 struct tipc_media_addr *maddr;
597 int rc = -EHOSTUNREACH;
599 __skb_queue_head_init(&xmitq);
600 n = tipc_node_find(net, dnode);
603 l = tipc_node_select_link(n, selector, &bearer_id, &maddr);
605 rc = tipc_link_xmit(l, list, &xmitq);
606 if (unlikely(rc == -ENOBUFS))
612 tipc_bearer_xmit(net, bearer_id, &xmitq, maddr);
615 if (likely(in_own_node(net, dnode))) {
616 tipc_sk_rcv(net, list);
622 /* tipc_node_xmit_skb(): send single buffer to destination
623 * Buffers sent via this functon are generally TIPC_SYSTEM_IMPORTANCE
624 * messages, which will not be rejected
625 * The only exception is datagram messages rerouted after secondary
626 * lookup, which are rare and safe to dispose of anyway.
627 * TODO: Return real return value, and let callers use
628 * tipc_wait_for_sendpkt() where applicable
630 int tipc_node_xmit_skb(struct net *net, struct sk_buff *skb, u32 dnode,
633 struct sk_buff_head head;
636 skb_queue_head_init(&head);
637 __skb_queue_tail(&head, skb);
638 rc = tipc_node_xmit(net, &head, dnode, selector);
639 if (rc == -ELINKCONG)
644 int tipc_nl_node_dump(struct sk_buff *skb, struct netlink_callback *cb)
647 struct net *net = sock_net(skb->sk);
648 struct tipc_net *tn = net_generic(net, tipc_net_id);
649 int done = cb->args[0];
650 int last_addr = cb->args[1];
651 struct tipc_node *node;
652 struct tipc_nl_msg msg;
658 msg.portid = NETLINK_CB(cb->skb).portid;
659 msg.seq = cb->nlh->nlmsg_seq;
663 node = tipc_node_find(net, last_addr);
666 /* We never set seq or call nl_dump_check_consistent()
667 * this means that setting prev_seq here will cause the
668 * consistence check to fail in the netlink callback
669 * handler. Resulting in the NLMSG_DONE message having
670 * the NLM_F_DUMP_INTR flag set if the node state
671 * changed while we released the lock.
679 list_for_each_entry_rcu(node, &tn->node_list, list) {
681 if (node->addr == last_addr)
687 tipc_node_lock(node);
688 err = __tipc_nl_add_node(&msg, node);
690 last_addr = node->addr;
691 tipc_node_unlock(node);
695 tipc_node_unlock(node);
700 cb->args[1] = last_addr;