ematch: Fix auto-loading of ematch modules.
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / sched / em_cmp.c
CommitLineData
1da177e4
LT
1/*
2 * net/sched/em_cmp.c Simple packet data comparison ematch
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
8 *
9 * Authors: Thomas Graf <tgraf@suug.ch>
10 */
11
1da177e4
LT
12#include <linux/module.h>
13#include <linux/types.h>
14#include <linux/kernel.h>
15#include <linux/skbuff.h>
16#include <linux/tc_ematch/tc_em_cmp.h>
d48abfec 17#include <asm/unaligned.h>
1da177e4
LT
18#include <net/pkt_cls.h>
19
20static inline int cmp_needs_transformation(struct tcf_em_cmp *cmp)
21{
22 return unlikely(cmp->flags & TCF_EM_CMP_TRANS);
23}
24
25static int em_cmp_match(struct sk_buff *skb, struct tcf_ematch *em,
26 struct tcf_pkt_info *info)
27{
28 struct tcf_em_cmp *cmp = (struct tcf_em_cmp *) em->data;
29 unsigned char *ptr = tcf_get_base_ptr(skb, cmp->layer) + cmp->off;
30 u32 val = 0;
31
32 if (!tcf_valid_offset(skb, ptr, cmp->align))
33 return 0;
34
35 switch (cmp->align) {
cc7ec456
ED
36 case TCF_EM_ALIGN_U8:
37 val = *ptr;
38 break;
1da177e4 39
cc7ec456
ED
40 case TCF_EM_ALIGN_U16:
41 val = get_unaligned_be16(ptr);
1da177e4 42
cc7ec456
ED
43 if (cmp_needs_transformation(cmp))
44 val = be16_to_cpu(val);
45 break;
1da177e4 46
cc7ec456
ED
47 case TCF_EM_ALIGN_U32:
48 /* Worth checking boundries? The branching seems
49 * to get worse. Visit again.
50 */
51 val = get_unaligned_be32(ptr);
1da177e4 52
cc7ec456
ED
53 if (cmp_needs_transformation(cmp))
54 val = be32_to_cpu(val);
55 break;
1da177e4 56
cc7ec456
ED
57 default:
58 return 0;
1da177e4
LT
59 }
60
61 if (cmp->mask)
62 val &= cmp->mask;
63
64 switch (cmp->opnd) {
cc7ec456
ED
65 case TCF_EM_OPND_EQ:
66 return val == cmp->val;
67 case TCF_EM_OPND_LT:
68 return val < cmp->val;
69 case TCF_EM_OPND_GT:
70 return val > cmp->val;
1da177e4
LT
71 }
72
73 return 0;
74}
75
76static struct tcf_ematch_ops em_cmp_ops = {
77 .kind = TCF_EM_CMP,
78 .datalen = sizeof(struct tcf_em_cmp),
79 .match = em_cmp_match,
80 .owner = THIS_MODULE,
81 .link = LIST_HEAD_INIT(em_cmp_ops.link)
82};
83
84static int __init init_em_cmp(void)
85{
86 return tcf_em_register(&em_cmp_ops);
87}
88
10297b99 89static void __exit exit_em_cmp(void)
1da177e4
LT
90{
91 tcf_em_unregister(&em_cmp_ops);
92}
93
94MODULE_LICENSE("GPL");
95
96module_init(init_em_cmp);
97module_exit(exit_em_cmp);
98
db3d99c0 99MODULE_ALIAS_TCF_EMATCH(TCF_EM_CMP);