/* * 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. * * INET protocol dispatch tables. * * Authors: Ross Biro * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> * * Fixes: * Alan Cox : Ahah! udp icmp errors don't work because * udp_err is never called! * Alan Cox : Added new fields for init and ready for * proper fragmentation (_NO_ 4K limits!) * Richard Colella : Hang on hash collision * Vince Laviano : Modified inet_del_protocol() to correctly * maintain copy bit. * * 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. */ #include <linux/cache.h> #include <linux/module.h> #include <linux/netdevice.h> #include <linux/spinlock.h> #include <net/protocol.h> const struct net_protocol *inet_protos[MAX_INET_PROTOS] ____cacheline_aligned_in_smp; static DEFINE_SPINLOCK(inet_proto_lock); /* * Add a protocol handler to the hash tables */ int inet_add_protocol(const struct net_protocol *prot, unsigned char protocol) { int hash, ret; hash = protocol & (MAX_INET_PROTOS - 1); spin_lock_bh(&inet_proto_lock); if (inet_protos[hash]) { ret = -1; } else { inet_protos[hash] = prot; ret = 0; } spin_unlock_bh(&inet_proto_lock); return ret; } /* * Remove a protocol from the hash tables. */ int inet_del_protocol(const struct net_protocol *prot, unsigned char protocol) { int hash, ret; hash = protocol & (MAX_INET_PROTOS - 1); spin_lock_bh(&inet_proto_lock); if (inet_protos[hash] == prot) { inet_protos[hash] = NULL; ret = 0; } else { ret = -1; } spin_unlock_bh(&inet_proto_lock); synchronize_net(); return ret; } EXPORT_SYMBOL(inet_add_protocol); EXPORT_SYMBOL(inet_del_protocol);