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 | EXPORT_SYMBOL(inet_protos); |
33 | const struct net_offload __rcu *inet_offloads[MAX_INET_PROTOS] __read_mostly; |
34 | EXPORT_SYMBOL(inet_offloads); |
35 | |
36 | int inet_add_protocol(const struct net_protocol *prot, unsigned char protocol) |
37 | { |
38 | if (!prot->netns_ok) { |
39 | pr_err("Protocol %u is not namespace aware, cannot register.\n" , |
40 | protocol); |
41 | return -EINVAL; |
42 | } |
43 | |
44 | return !cmpxchg((const struct net_protocol **)&inet_protos[protocol], |
45 | NULL, prot) ? 0 : -1; |
46 | } |
47 | EXPORT_SYMBOL(inet_add_protocol); |
48 | |
49 | int inet_add_offload(const struct net_offload *prot, unsigned char protocol) |
50 | { |
51 | return !cmpxchg((const struct net_offload **)&inet_offloads[protocol], |
52 | NULL, prot) ? 0 : -1; |
53 | } |
54 | EXPORT_SYMBOL(inet_add_offload); |
55 | |
56 | int inet_del_protocol(const struct net_protocol *prot, unsigned char protocol) |
57 | { |
58 | int ret; |
59 | |
60 | ret = (cmpxchg((const struct net_protocol **)&inet_protos[protocol], |
61 | prot, NULL) == prot) ? 0 : -1; |
62 | |
63 | synchronize_net(); |
64 | |
65 | return ret; |
66 | } |
67 | EXPORT_SYMBOL(inet_del_protocol); |
68 | |
69 | int inet_del_offload(const struct net_offload *prot, unsigned char protocol) |
70 | { |
71 | int ret; |
72 | |
73 | ret = (cmpxchg((const struct net_offload **)&inet_offloads[protocol], |
74 | prot, NULL) == prot) ? 0 : -1; |
75 | |
76 | synchronize_net(); |
77 | |
78 | return ret; |
79 | } |
80 | EXPORT_SYMBOL(inet_del_offload); |
81 | |