net/tipc/node.h

   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
  76 struct 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
 102 extern 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  */
 110 static inline unsigned int tipc_hashfn(u32 addr)
 111 {
 112         return addr & (NODE_HTABLE_SIZE - 1);
 113 }
 114
 115 extern u32 tipc_own_tag;
 116
 117 struct tipc_node *tipc_node_find(u32 addr);
 118 struct tipc_node *tipc_node_create(u32 addr);
 119 void tipc_node_delete(struct tipc_node *n_ptr);
 120 void tipc_node_attach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr);
 121 void tipc_node_detach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr);
 122 void tipc_node_link_down(struct tipc_node *n_ptr, struct tipc_link *l_ptr);
 123 void tipc_node_link_up(struct tipc_node *n_ptr, struct tipc_link *l_ptr);
 124 int tipc_node_active_links(struct tipc_node *n_ptr);
 125 int tipc_node_redundant_links(struct tipc_node *n_ptr);
 126 int tipc_node_is_up(struct tipc_node *n_ptr);
 127 struct sk_buff *tipc_node_get_links(const void *req_tlv_area, int req_tlv_space);
 128 struct sk_buff *tipc_node_get_nodes(const void *req_tlv_area, int req_tlv_space);
 129
 130 static inline void tipc_node_lock(struct tipc_node *n_ptr)
 131 {
 132         spin_lock_bh(&n_ptr->lock);
 133 }
 134
 135 static inline void tipc_node_unlock(struct tipc_node *n_ptr)
 136 {
 137         spin_unlock_bh(&n_ptr->lock);
 138 }
 139
 140 #endif