/* * 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. * * Version:	$Id: protocol.c,v 1.10 2001/05/18 02:25:49 davem Exp $ * * 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/errno.h>#include <linux/types.h>#include <linux/socket.h>#include <linux/sockios.h>#include <linux/net.h>#include <linux/in6.h>#include <linux/netdevice.h>#include <linux/if_arp.h> #include <net/sock.h>#include <net/snmp.h> #include <net/ipv6.h>#include <net/protocol.h> struct inet6_protocol *inet6_protos[MAX_INET_PROTOS];static DEFINE_SPINLOCK(inet6_proto_lock);  int inet6_add_protocol(struct inet6_protocol *prot, unsigned char protocol){	int ret, hash = protocol & (MAX_INET_PROTOS - 1); 	spin_lock_bh(&inet6_proto_lock); 	if (inet6_protos[hash]) {		ret = -1;	} else {		inet6_protos[hash] = prot;		ret = 0;	} 	spin_unlock_bh(&inet6_proto_lock); 	return ret;} /* *	Remove a protocol from the hash tables. */ int inet6_del_protocol(struct inet6_protocol *prot, unsigned char protocol){	int ret, hash = protocol & (MAX_INET_PROTOS - 1); 	spin_lock_bh(&inet6_proto_lock); 	if (inet6_protos[hash] != prot) {		ret = -1;	} else {		inet6_protos[hash] = NULL;		ret = 0;	} 	spin_unlock_bh(&inet6_proto_lock); 	synchronize_net(); 	return ret;}