blob: a2e5fc0a15e15eff1abdecba3d94c870fc2054ec [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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.
5 *
6 * INET protocol dispatch tables.
7 *
Jesper Juhl02c30a82005-05-05 16:16:16 -07008 * Authors: Ross Biro
Linus Torvalds1da177e2005-04-16 15:20:36 -07009 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
10 *
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.
19 *
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.
24 */
Alexey Dobriyanfa1a9c62009-09-09 03:43:50 -070025#include <linux/cache.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070026#include <linux/module.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070027#include <linux/netdevice.h>
Alexey Dobriyanfa1a9c62009-09-09 03:43:50 -070028#include <linux/spinlock.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070029#include <net/protocol.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070030
Eric Dumazet03d4f872007-03-27 14:18:34 -070031struct net_protocol *inet_protos[MAX_INET_PROTOS] ____cacheline_aligned_in_smp;
Linus Torvalds1da177e2005-04-16 15:20:36 -070032static DEFINE_SPINLOCK(inet_proto_lock);
33
34/*
35 * Add a protocol handler to the hash tables
36 */
37
38int inet_add_protocol(struct net_protocol *prot, unsigned char protocol)
39{
40 int hash, ret;
41
42 hash = protocol & (MAX_INET_PROTOS - 1);
43
44 spin_lock_bh(&inet_proto_lock);
45 if (inet_protos[hash]) {
46 ret = -1;
47 } else {
48 inet_protos[hash] = prot;
49 ret = 0;
50 }
51 spin_unlock_bh(&inet_proto_lock);
52
53 return ret;
54}
55
56/*
57 * Remove a protocol from the hash tables.
58 */
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +090059
Linus Torvalds1da177e2005-04-16 15:20:36 -070060int inet_del_protocol(struct net_protocol *prot, unsigned char protocol)
61{
62 int hash, ret;
63
64 hash = protocol & (MAX_INET_PROTOS - 1);
65
66 spin_lock_bh(&inet_proto_lock);
67 if (inet_protos[hash] == prot) {
68 inet_protos[hash] = NULL;
69 ret = 0;
70 } else {
71 ret = -1;
72 }
73 spin_unlock_bh(&inet_proto_lock);
74
75 synchronize_net();
76
77 return ret;
78}
79
80EXPORT_SYMBOL(inet_add_protocol);
81EXPORT_SYMBOL(inet_del_protocol);