net/tipc/core.c

   1 /*
   2  * net/tipc/core.c: TIPC module code
   3  *
   4  * Copyright (c) 2003-2006, Ericsson AB
   5  * Copyright (c) 2005-2006, 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 "ref.h"
  39 #include "name_table.h"
  40 #include "subscr.h"
  41 #include "config.h"
  42
  43 #include <linux/module.h>
  44
  45 /* global variables used by multiple sub-systems within TIPC */
  46 int tipc_random __read_mostly;
  47
  48 /* configurable TIPC parameters */
  49 u32 tipc_own_addr __read_mostly;
  50 int tipc_max_ports __read_mostly;
  51 int tipc_net_id __read_mostly;
  52 int tipc_remote_management __read_mostly;
  53
  54
  55 /**
  56  * tipc_buf_acquire - creates a TIPC message buffer
  57  * @size: message size (including TIPC header)
  58  *
  59  * Returns a new buffer with data pointers set to the specified size.
  60  *
  61  * NOTE: Headroom is reserved to allow prepending of a data link header.
  62  *       There may also be unrequested tailroom present at the buffer's end.
  63  */
  64 struct sk_buff *tipc_buf_acquire(u32 size)
  65 {
  66         struct sk_buff *skb;
  67         unsigned int buf_size = (BUF_HEADROOM + size + 3) & ~3u;
  68
  69         skb = alloc_skb_fclone(buf_size, GFP_ATOMIC);
  70         if (skb) {
  71                 skb_reserve(skb, BUF_HEADROOM);
  72                 skb_put(skb, size);
  73                 skb->next = NULL;
  74         }
  75         return skb;
  76 }
  77
  78 /**
  79  * tipc_core_stop_net - shut down TIPC networking sub-systems
  80  */
  81 static void tipc_core_stop_net(void)
  82 {
  83         tipc_net_stop();
  84         tipc_eth_media_stop();
  85 }
  86
  87 /**
  88  * start_net - start TIPC networking sub-systems
  89  */
  90 int tipc_core_start_net(unsigned long addr)
  91 {
  92         int res;
  93
  94         tipc_net_start(addr);
  95         res = tipc_eth_media_start();
  96         if (res)
  97                 tipc_core_stop_net();
  98         return res;
  99 }
 100
 101 /**
 102  * tipc_core_stop - switch TIPC from SINGLE NODE to NOT RUNNING mode
 103  */
 104 static void tipc_core_stop(void)
 105 {
 106         tipc_netlink_stop();
 107         tipc_handler_stop();
 108         tipc_cfg_stop();
 109         tipc_subscr_stop();
 110         tipc_nametbl_stop();
 111         tipc_ref_table_stop();
 112         tipc_socket_stop();
 113 }
 114
 115 /**
 116  * tipc_core_start - switch TIPC from NOT RUNNING to SINGLE NODE mode
 117  */
 118 static int tipc_core_start(void)
 119 {
 120         int res;
 121
 122         get_random_bytes(&tipc_random, sizeof(tipc_random));
 123
 124         res = tipc_handler_start();
 125         if (!res)
 126                 res = tipc_ref_table_init(tipc_max_ports, tipc_random);
 127         if (!res)
 128                 res = tipc_nametbl_init();
 129         if (!res)
 130                 res = tipc_subscr_start();
 131         if (!res)
 132                 res = tipc_cfg_init();
 133         if (!res)
 134                 res = tipc_netlink_start();
 135         if (!res)
 136                 res = tipc_socket_init();
 137         if (res)
 138                 tipc_core_stop();
 139
 140         return res;
 141 }
 142
 143
 144 static int __init tipc_init(void)
 145 {
 146         int res;
 147
 148         pr_info("Activated (version " TIPC_MOD_VER ")\n");
 149
 150         tipc_own_addr = 0;
 151         tipc_remote_management = 1;
 152         tipc_max_ports = CONFIG_TIPC_PORTS;
 153         tipc_net_id = 4711;
 154
 155         res = tipc_core_start();
 156         if (res)
 157                 pr_err("Unable to start in single node mode\n");
 158         else
 159                 pr_info("Started in single node mode\n");
 160         return res;
 161 }
 162
 163 static void __exit tipc_exit(void)
 164 {
 165         tipc_core_stop_net();
 166         tipc_core_stop();
 167         pr_info("Deactivated\n");
 168 }
 169
 170 module_init(tipc_init);
 171 module_exit(tipc_exit);
 172
 173 MODULE_DESCRIPTION("TIPC: Transparent Inter Process Communication");
 174 MODULE_LICENSE("Dual BSD/GPL");
 175 MODULE_VERSION(TIPC_MOD_VER);