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, 2010-2013, 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 #include "port.h"
  43
  44 #include <linux/module.h>
  45
  46 /* global variables used by multiple sub-systems within TIPC */
  47 int tipc_random __read_mostly;
  48
  49 /* configurable TIPC parameters */
  50 u32 tipc_own_addr __read_mostly;
  51 int tipc_max_ports __read_mostly;
  52 int tipc_net_id __read_mostly;
  53 int tipc_remote_management __read_mostly;
  54 int sysctl_tipc_rmem[3] __read_mostly;  /* min/default/max */
  55
  56 /**
  57  * tipc_buf_acquire - creates a TIPC message buffer
  58  * @size: message size (including TIPC header)
  59  *
  60  * Returns a new buffer with data pointers set to the specified size.
  61  *
  62  * NOTE: Headroom is reserved to allow prepending of a data link header.
  63  *       There may also be unrequested tailroom present at the buffer's end.
  64  */
  65 struct sk_buff *tipc_buf_acquire(u32 size)
  66 {
  67         struct sk_buff *skb;
  68         unsigned int buf_size = (BUF_HEADROOM + size + 3) & ~3u;
  69
  70         skb = alloc_skb_fclone(buf_size, GFP_ATOMIC);
  71         if (skb) {
  72                 skb_reserve(skb, BUF_HEADROOM);
  73                 skb_put(skb, size);
  74                 skb->next = NULL;
  75         }
  76         return skb;
  77 }
  78
  79 /**
  80  * tipc_core_stop_net - shut down TIPC networking sub-systems
  81  */
  82 static void tipc_core_stop_net(void)
  83 {
  84         tipc_net_stop();
  85         tipc_bearer_cleanup();
  86 }
  87
  88 /**
  89  * start_net - start TIPC networking sub-systems
  90  */
  91 int tipc_core_start_net(unsigned long addr)
  92 {
  93         int res;
  94
  95         tipc_net_start(addr);
  96         res = tipc_bearer_setup();
  97         if (res < 0)
  98                 goto err;
  99         return res;
 100
 101 err:
 102         tipc_core_stop_net();
 103         return res;
 104 }
 105
 106 /**
 107  * tipc_core_stop - switch TIPC from SINGLE NODE to NOT RUNNING mode
 108  */
 109 static void tipc_core_stop(void)
 110 {
 111         tipc_netlink_stop();
 112         tipc_cfg_stop();
 113         tipc_subscr_stop();
 114         tipc_nametbl_stop();
 115         tipc_ref_table_stop();
 116         tipc_socket_stop();
 117         tipc_unregister_sysctl();
 118 }
 119
 120 /**
 121  * tipc_core_start - switch TIPC from NOT RUNNING to SINGLE NODE mode
 122  */
 123 static int tipc_core_start(void)
 124 {
 125         int res;
 126
 127         get_random_bytes(&tipc_random, sizeof(tipc_random));
 128
 129         res = tipc_handler_start();
 130         if (!res)
 131                 res = tipc_ref_table_init(tipc_max_ports, tipc_random);
 132         if (!res)
 133                 res = tipc_nametbl_init();
 134         if (!res)
 135                 res = tipc_netlink_start();
 136         if (!res)
 137                 res = tipc_socket_init();
 138         if (!res)
 139                 res = tipc_register_sysctl();
 140         if (!res)
 141                 res = tipc_subscr_start();
 142         if (!res)
 143                 res = tipc_cfg_init();
 144         if (res) {
 145                 tipc_handler_stop();
 146                 tipc_core_stop();
 147         }
 148         return res;
 149 }
 150
 151 static int __init tipc_init(void)
 152 {
 153         int res;
 154
 155         pr_info("Activated (version " TIPC_MOD_VER ")\n");
 156
 157         tipc_own_addr = 0;
 158         tipc_remote_management = 1;
 159         tipc_max_ports = CONFIG_TIPC_PORTS;
 160         tipc_net_id = 4711;
 161
 162         sysctl_tipc_rmem[0] = CONN_OVERLOAD_LIMIT >> 4 << TIPC_LOW_IMPORTANCE;
 163         sysctl_tipc_rmem[1] = CONN_OVERLOAD_LIMIT >> 4 <<
 164                               TIPC_CRITICAL_IMPORTANCE;
 165         sysctl_tipc_rmem[2] = CONN_OVERLOAD_LIMIT;
 166
 167         res = tipc_core_start();
 168         if (res)
 169                 pr_err("Unable to start in single node mode\n");
 170         else
 171                 pr_info("Started in single node mode\n");
 172         return res;
 173 }
 174
 175 static void __exit tipc_exit(void)
 176 {
 177         tipc_handler_stop();
 178         tipc_core_stop_net();
 179         tipc_core_stop();
 180         pr_info("Deactivated\n");
 181 }
 182
 183 module_init(tipc_init);
 184 module_exit(tipc_exit);
 185
 186 MODULE_DESCRIPTION("TIPC: Transparent Inter Process Communication");
 187 MODULE_LICENSE("Dual BSD/GPL");
 188 MODULE_VERSION(TIPC_MOD_VER);