| 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 | void tipc_nodesub_subscribe(struct tipc_node_subscr *node_sub, u32 addr, |
| 45 | void *usr_handle, net_ev_handler handle_down) |
| 46 | { |
| 47 | if (in_own_node(addr)) { |
| 48 | node_sub->node = NULL; |
| 49 | return; |
| 50 | } |
| 51 | |
| 52 | node_sub->node = tipc_node_find(addr); |
| 53 | if (!node_sub->node) { |
| 54 | pr_warn("Node subscription rejected, unknown node 0x%x\n", |
| 55 | 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 | void tipc_nodesub_unsubscribe(struct tipc_node_subscr *node_sub) |
| 70 | { |
| 71 | if (!node_sub->node) |
| 72 | return; |
| 73 | |
| 74 | tipc_node_lock(node_sub->node); |
| 75 | list_del_init(&node_sub->nodesub_list); |
| 76 | tipc_node_unlock(node_sub->node); |
| 77 | } |
| 78 | |
| 79 | /** |
| 80 | * tipc_nodesub_notify - notify subscribers that a node is unreachable |
| 81 | * |
| 82 | * Note: node is locked by caller |
| 83 | */ |
| 84 | void tipc_nodesub_notify(struct list_head *nsub_list) |
| 85 | { |
| 86 | struct tipc_node_subscr *ns, *safe; |
| 87 | net_ev_handler handle_node_down; |
| 88 | |
| 89 | list_for_each_entry_safe(ns, safe, nsub_list, nodesub_list) { |
| 90 | handle_node_down = ns->handle_node_down; |
| 91 | if (handle_node_down) { |
| 92 | ns->handle_node_down = NULL; |
| 93 | handle_node_down(ns->usr_handle); |
| 94 | } |
| 95 | } |
| 96 | } |