node.h revision a18c4bc3ea3c23f658655b1eee4f62cb71d51efd 
1/*
2 * net/tipc/node.h: Include file for TIPC node management routines
3 *
4 * Copyright (c) 2000-2006, 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#ifndef _TIPC_NODE_H
38#define _TIPC_NODE_H
39
40#include "node_subscr.h"
41#include "addr.h"
42#include "net.h"
43#include "bearer.h"
44
45/* Flags used to block (re)establishment of contact with a neighboring node */
46
47#define WAIT_PEER_DOWN	0x0001	/* wait to see that peer's links are down */
48#define WAIT_NAMES_GONE	0x0002	/* wait for peer's publications to be purged */
49#define WAIT_NODE_DOWN	0x0004	/* wait until peer node is declared down */
50
51/**
52 * struct tipc_node - TIPC node structure
53 * @addr: network address of node
54 * @lock: spinlock governing access to structure
55 * @hash: links to adjacent nodes in unsorted hash chain
56 * @list: links to adjacent nodes in sorted list of cluster's nodes
57 * @nsub: list of "node down" subscriptions monitoring node
58 * @active_links: pointers to active links to node
59 * @links: pointers to all links to node
60 * @working_links: number of working links to node (both active and standby)
61 * @block_setup: bit mask of conditions preventing link establishment to node
62 * @link_cnt: number of links to node
63 * @permit_changeover: non-zero if node has redundant links to this system
64 * @bclink: broadcast-related info
65 *    @supported: non-zero if node supports TIPC b'cast capability
66 *    @acked: sequence # of last outbound b'cast message acknowledged by node
67 *    @last_in: sequence # of last in-sequence b'cast message received from node
68 *    @gap_after: sequence # of last message not requiring a NAK request
69 *    @gap_to: sequence # of last message requiring a NAK request
70 *    @nack_sync: counter that determines when NAK requests should be sent
71 *    @deferred_head: oldest OOS b'cast message received from node
72 *    @deferred_tail: newest OOS b'cast message received from node
73 *    @defragm: list of partially reassembled b'cast message fragments from node
74 */
75
76struct tipc_node {
77	u32 addr;
78	spinlock_t lock;
79	struct hlist_node hash;
80	struct list_head list;
81	struct list_head nsub;
82	struct tipc_link *active_links[2];
83	struct tipc_link *links[MAX_BEARERS];
84	int link_cnt;
85	int working_links;
86	int block_setup;
87	int permit_changeover;
88	struct {
89		int supported;
90		u32 acked;
91		u32 last_in;
92		u32 gap_after;
93		u32 gap_to;
94		u32 nack_sync;
95		struct sk_buff *deferred_head;
96		struct sk_buff *deferred_tail;
97		struct sk_buff *defragm;
98	} bclink;
99};
100
101#define NODE_HTABLE_SIZE 512
102extern struct list_head tipc_node_list;
103
104/*
105 * A trivial power-of-two bitmask technique is used for speed, since this
106 * operation is done for every incoming TIPC packet. The number of hash table
107 * entries has been chosen so that no hash chain exceeds 8 nodes and will
108 * usually be much smaller (typically only a single node).
109 */
110static inline unsigned int tipc_hashfn(u32 addr)
111{
112	return addr & (NODE_HTABLE_SIZE - 1);
113}
114
115extern u32 tipc_own_tag;
116
117struct tipc_node *tipc_node_find(u32 addr);
118struct tipc_node *tipc_node_create(u32 addr);
119void tipc_node_delete(struct tipc_node *n_ptr);
120void tipc_node_attach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr);
121void tipc_node_detach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr);
122void tipc_node_link_down(struct tipc_node *n_ptr, struct tipc_link *l_ptr);
123void tipc_node_link_up(struct tipc_node *n_ptr, struct tipc_link *l_ptr);
124int tipc_node_active_links(struct tipc_node *n_ptr);
125int tipc_node_redundant_links(struct tipc_node *n_ptr);
126int tipc_node_is_up(struct tipc_node *n_ptr);
127struct sk_buff *tipc_node_get_links(const void *req_tlv_area, int req_tlv_space);
128struct sk_buff *tipc_node_get_nodes(const void *req_tlv_area, int req_tlv_space);
129
130static inline void tipc_node_lock(struct tipc_node *n_ptr)
131{
132	spin_lock_bh(&n_ptr->lock);
133}
134
135static inline void tipc_node_unlock(struct tipc_node *n_ptr)
136{
137	spin_unlock_bh(&n_ptr->lock);
138}
139
140#endif
141