/*
   * net/tipc/core.c: TIPC module code
   *

   * Copyright (c) 2003-2006, Ericsson AB

   * Copyright (c) 2005-2006, 2010-2011, Wind River Systems

   * All rights reserved.
   *

   * Redistribution and use in source and binary forms, with or without

   * modification, are permitted provided that the following conditions are met:
   *

   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   * 3. Neither the names of the copyright holders nor the names of its
   *    contributors may be used to endorse or promote products derived from
   *    this software without specific prior written permission.

   *

   * Alternatively, this software may be distributed under the terms of the
   * GNU General Public License ("GPL") version 2 as published by the Free
   * Software Foundation.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

   * POSSIBILITY OF SUCH DAMAGE.
   */

  #include <linux/module.h>

  #include "core.h"

  #include "ref.h"

  #include "name_table.h"
  #include "subscr.h"
  #include "config.h"

  #ifndef CONFIG_TIPC_PORTS
  #define CONFIG_TIPC_PORTS 8191
  #endif
  
  #ifndef CONFIG_TIPC_LOG
  #define CONFIG_TIPC_LOG 0
  #endif
  
  /* global variables used by multiple sub-systems within TIPC */
  
  int tipc_mode = TIPC_NOT_RUNNING;
  int tipc_random;

  const char tipc_alphabet[] =

  	"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789_.";

  
  /* configurable TIPC parameters */
  
  u32 tipc_own_addr;

  int tipc_max_ports;
  int tipc_max_subscriptions;
  int tipc_max_publications;
  int tipc_net_id;
  int tipc_remote_management;

  /**

   * tipc_buf_acquire - creates a TIPC message buffer

   * @size: message size (including TIPC header)
   *
   * Returns a new buffer with data pointers set to the specified size.
   *
   * NOTE: Headroom is reserved to allow prepending of a data link header.
   *       There may also be unrequested tailroom present at the buffer's end.
   */

  struct sk_buff *tipc_buf_acquire(u32 size)

  {
  	struct sk_buff *skb;
  	unsigned int buf_size = (BUF_HEADROOM + size + 3) & ~3u;
  
  	skb = alloc_skb_fclone(buf_size, GFP_ATOMIC);
  	if (skb) {
  		skb_reserve(skb, BUF_HEADROOM);
  		skb_put(skb, size);
  		skb->next = NULL;
  	}
  	return skb;
  }
  
  /**

   * tipc_core_stop_net - shut down TIPC networking sub-systems

   */

  static void tipc_core_stop_net(void)

  {

  	tipc_net_stop();

  	tipc_eth_media_stop();

  }
  
  /**
   * start_net - start TIPC networking sub-systems
   */

  int tipc_core_start_net(unsigned long addr)

  {
  	int res;

  	res = tipc_net_start(addr);
  	if (!res)
  		res = tipc_eth_media_start();
  	if (res)

  		tipc_core_stop_net();

  	return res;
  }
  
  /**

   * tipc_core_stop - switch TIPC from SINGLE NODE to NOT RUNNING mode

   */

  static void tipc_core_stop(void)

  {
  	if (tipc_mode != TIPC_NODE_MODE)
  		return;
  
  	tipc_mode = TIPC_NOT_RUNNING;

  	tipc_netlink_stop();
  	tipc_handler_stop();
  	tipc_cfg_stop();
  	tipc_subscr_stop();

  	tipc_nametbl_stop();
  	tipc_ref_table_stop();
  	tipc_socket_stop();

  	tipc_log_resize(0);

  }
  
  /**

   * tipc_core_start - switch TIPC from NOT RUNNING to SINGLE NODE mode

   */

  static int tipc_core_start(void)

  {
  	int res;
  
  	if (tipc_mode != TIPC_NOT_RUNNING)
  		return -ENOPROTOOPT;
  
  	get_random_bytes(&tipc_random, sizeof(tipc_random));
  	tipc_mode = TIPC_NODE_MODE;

  	res = tipc_handler_start();
  	if (!res)
  		res = tipc_ref_table_init(tipc_max_ports, tipc_random);
  	if (!res)
  		res = tipc_nametbl_init();
  	if (!res)
  		res = tipc_k_signal((Handler)tipc_subscr_start, 0);
  	if (!res)
  		res = tipc_k_signal((Handler)tipc_cfg_init, 0);
  	if (!res)
  		res = tipc_netlink_start();
  	if (!res)
  		res = tipc_socket_init();
  	if (res)

  		tipc_core_stop();

  	return res;
  }
  
  
  static int __init tipc_init(void)
  {
  	int res;

  	if (tipc_log_resize(CONFIG_TIPC_LOG) != 0)
  		warn("Unable to create log buffer
  ");

  	info("Activated (version " TIPC_MOD_VER ")
  ");

  
  	tipc_own_addr = 0;
  	tipc_remote_management = 1;
  	tipc_max_publications = 10000;
  	tipc_max_subscriptions = 2000;

  	tipc_max_ports = CONFIG_TIPC_PORTS;

  	tipc_net_id = 4711;

  	res = tipc_core_start();
  	if (res)

  		err("Unable to start in single node mode
  ");

  	else

  		info("Started in single node mode
  ");

  	return res;

  }
  
  static void __exit tipc_exit(void)
  {

  	tipc_core_stop_net();
  	tipc_core_stop();

  	info("Deactivated
  ");

  }
  
  module_init(tipc_init);
  module_exit(tipc_exit);
  
  MODULE_DESCRIPTION("TIPC: Transparent Inter Process Communication");
  MODULE_LICENSE("Dual BSD/GPL");

  MODULE_VERSION(TIPC_MOD_VER);