[CIFS] remove checkpatch warning
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / ipv4 / protocol.c
blobea50da0649fd4c5ed06f7f9b892b26c356ee5601
1 /*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
6 * INET protocol dispatch tables.
8 * Authors: Ross Biro
9 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
11 * Fixes:
12 * Alan Cox : Ahah! udp icmp errors don't work because
13 * udp_err is never called!
14 * Alan Cox : Added new fields for init and ready for
15 * proper fragmentation (_NO_ 4K limits!)
16 * Richard Colella : Hang on hash collision
17 * Vince Laviano : Modified inet_del_protocol() to correctly
18 * maintain copy bit.
20 * This program is free software; you can redistribute it and/or
21 * modify it under the terms of the GNU General Public License
22 * as published by the Free Software Foundation; either version
23 * 2 of the License, or (at your option) any later version.
26 #include <asm/uaccess.h>
27 #include <asm/system.h>
28 #include <linux/module.h>
29 #include <linux/types.h>
30 #include <linux/kernel.h>
31 #include <linux/string.h>
32 #include <linux/socket.h>
33 #include <linux/in.h>
34 #include <linux/inet.h>
35 #include <linux/netdevice.h>
36 #include <linux/timer.h>
37 #include <net/ip.h>
38 #include <net/protocol.h>
39 #include <linux/skbuff.h>
40 #include <net/sock.h>
41 #include <net/icmp.h>
42 #include <net/udp.h>
43 #include <net/ipip.h>
44 #include <linux/igmp.h>
46 struct net_protocol *inet_protos[MAX_INET_PROTOS] ____cacheline_aligned_in_smp;
47 static DEFINE_SPINLOCK(inet_proto_lock);
50 * Add a protocol handler to the hash tables
53 int inet_add_protocol(struct net_protocol *prot, unsigned char protocol)
55 int hash, ret;
57 hash = protocol & (MAX_INET_PROTOS - 1);
59 spin_lock_bh(&inet_proto_lock);
60 if (inet_protos[hash]) {
61 ret = -1;
62 } else {
63 inet_protos[hash] = prot;
64 ret = 0;
66 spin_unlock_bh(&inet_proto_lock);
68 return ret;
72 * Remove a protocol from the hash tables.
75 int inet_del_protocol(struct net_protocol *prot, unsigned char protocol)
77 int hash, ret;
79 hash = protocol & (MAX_INET_PROTOS - 1);
81 spin_lock_bh(&inet_proto_lock);
82 if (inet_protos[hash] == prot) {
83 inet_protos[hash] = NULL;
84 ret = 0;
85 } else {
86 ret = -1;
88 spin_unlock_bh(&inet_proto_lock);
90 synchronize_net();
92 return ret;
95 EXPORT_SYMBOL(inet_add_protocol);
96 EXPORT_SYMBOL(inet_del_protocol);