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. |
5 | * |
6 | * INET protocol dispatch tables. |
7 | * |
8 | * Authors: Ross Biro |
9 | * 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 | */ |
25 | #include <linux/cache.h> |
26 | #include <linux/module.h> |
27 | #include <linux/netdevice.h> |
28 | #include <linux/spinlock.h> |
29 | #include <net/protocol.h> |
30 | |
31 | struct net_protocol __rcu *inet_protos[MAX_INET_PROTOS] __read_mostly; |
32 | const struct net_offload __rcu *inet_offloads[MAX_INET_PROTOS] __read_mostly; |
33 | EXPORT_SYMBOL(inet_offloads); |
34 | |
35 | int inet_add_protocol(const struct net_protocol *prot, unsigned char protocol) |
36 | { |
37 | if (!prot->netns_ok) { |
38 | pr_err("Protocol %u is not namespace aware, cannot register.\n" , |
39 | protocol); |
40 | return -EINVAL; |
41 | } |
42 | |
43 | return !cmpxchg((const struct net_protocol **)&inet_protos[protocol], |
44 | NULL, prot) ? 0 : -1; |
45 | } |
46 | EXPORT_SYMBOL(inet_add_protocol); |
47 | |
48 | int inet_add_offload(const struct net_offload *prot, unsigned char protocol) |
49 | { |
50 | return !cmpxchg((const struct net_offload **)&inet_offloads[protocol], |
51 | NULL, prot) ? 0 : -1; |
52 | } |
53 | EXPORT_SYMBOL(inet_add_offload); |
54 | |
55 | int inet_del_protocol(const struct net_protocol *prot, unsigned char protocol) |
56 | { |
57 | int ret; |
58 | |
59 | ret = (cmpxchg((const struct net_protocol **)&inet_protos[protocol], |
60 | prot, NULL) == prot) ? 0 : -1; |
61 | |
62 | synchronize_net(); |
63 | |
64 | return ret; |
65 | } |
66 | EXPORT_SYMBOL(inet_del_protocol); |
67 | |
68 | int inet_del_offload(const struct net_offload *prot, unsigned char protocol) |
69 | { |
70 | int ret; |
71 | |
72 | ret = (cmpxchg((const struct net_offload **)&inet_offloads[protocol], |
73 | prot, NULL) == prot) ? 0 : -1; |
74 | |
75 | synchronize_net(); |
76 | |
77 | return ret; |
78 | } |
79 | EXPORT_SYMBOL(inet_del_offload); |
80 | |