/*
   * INET		An implementation of the TCP/IP protocol suite for the LINUX
   *		operating system.  INET is implemented using the  BSD Socket
   *		interface as the means of communication with the user level.
   *
   *		PF_INET6 protocol dispatch tables.
   *

   * Authors:	Pedro Roque	<roque@di.fc.ul.pt>
   *
   *		This program is free software; you can redistribute it and/or
   *		modify it under the terms of the GNU General Public License
   *		as published by the Free Software Foundation; either version
   *		2 of the License, or (at your option) any later version.
   */
  
  /*
   *      Changes:
   *
   *      Vince Laviano (vince@cs.stanford.edu)       16 May 2001
   *      - Removed unused variable 'inet6_protocol_base'
   *      - Modified inet6_del_protocol() to correctly maintain copy bit.
   */

  #include <linux/module.h>

  #include <linux/netdevice.h>

  #include <linux/spinlock.h>

  #include <net/protocol.h>

  const struct inet6_protocol __rcu *inet6_protos[MAX_INET_PROTOS] __read_mostly;

  int inet6_add_protocol(const struct inet6_protocol *prot, unsigned char protocol)

  {

  	int hash = protocol & (MAX_INET_PROTOS - 1);

  	return !cmpxchg((const struct inet6_protocol **)&inet6_protos[hash],
  			NULL, prot) ? 0 : -1;

  }

  EXPORT_SYMBOL(inet6_add_protocol);

  /*
   *	Remove a protocol from the hash tables.
   */

  int inet6_del_protocol(const struct inet6_protocol *prot, unsigned char protocol)

  {
  	int ret, hash = protocol & (MAX_INET_PROTOS - 1);

  	ret = (cmpxchg((const struct inet6_protocol **)&inet6_protos[hash],
  		       prot, NULL) == prot) ? 0 : -1;

  
  	synchronize_net();
  
  	return ret;
  }

  EXPORT_SYMBOL(inet6_del_protocol);