1 /*
2 * net/tipc/node_subscr.c: TIPC "node down" subscription handling
3 *
4 * Copyright (c) 1995-2006, Ericsson AB
5 * Copyright (c) 2005, 2010-2011, Wind River Systems
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
10 *
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.
19 *
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.
23 *
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.
35 */
36
37 #include "core.h"
38 #include "node_subscr.h"
39 #include "node.h"
40
41 /**
42 * tipc_nodesub_subscribe - create "node down" subscription for specified node
43 */
44
tipc_nodesub_subscribe(struct tipc_node_subscr * node_sub,u32 addr,void * usr_handle,net_ev_handler handle_down)45 void tipc_nodesub_subscribe(struct tipc_node_subscr *node_sub, u32 addr,
46 void *usr_handle, net_ev_handler handle_down)
47 {
48 if (addr == tipc_own_addr) {
49 node_sub->node = NULL;
50 return;
51 }
52
53 node_sub->node = tipc_node_find(addr);
54 if (!node_sub->node) {
55 warn("Node subscription rejected, unknown node 0x%x\n", addr);
56 return;
57 }
58 node_sub->handle_node_down = handle_down;
59 node_sub->usr_handle = usr_handle;
60
61 tipc_node_lock(node_sub->node);
62 list_add_tail(&node_sub->nodesub_list, &node_sub->node->nsub);
63 tipc_node_unlock(node_sub->node);
64 }
65
66 /**
67 * tipc_nodesub_unsubscribe - cancel "node down" subscription (if any)
68 */
69
tipc_nodesub_unsubscribe(struct tipc_node_subscr * node_sub)70 void tipc_nodesub_unsubscribe(struct tipc_node_subscr *node_sub)
71 {
72 if (!node_sub->node)
73 return;
74
75 tipc_node_lock(node_sub->node);
76 list_del_init(&node_sub->nodesub_list);
77 tipc_node_unlock(node_sub->node);
78 }
79
80 /**
81 * tipc_nodesub_notify - notify subscribers that a node is unreachable
82 *
83 * Note: node is locked by caller
84 */
85
tipc_nodesub_notify(struct tipc_node * node)86 void tipc_nodesub_notify(struct tipc_node *node)
87 {
88 struct tipc_node_subscr *ns;
89
90 list_for_each_entry(ns, &node->nsub, nodesub_list) {
91 if (ns->handle_node_down) {
92 tipc_k_signal((Handler)ns->handle_node_down,
93 (unsigned long)ns->usr_handle);
94 ns->handle_node_down = NULL;
95 }
96 }
97 }
98