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Diffstat (limited to 'arch/cris/include/asm/checksum.h')
-rw-r--r-- | arch/cris/include/asm/checksum.h | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/arch/cris/include/asm/checksum.h b/arch/cris/include/asm/checksum.h new file mode 100644 index 000000000000..75dcb77d6cb0 --- /dev/null +++ b/arch/cris/include/asm/checksum.h | |||
@@ -0,0 +1,83 @@ | |||
1 | /* TODO: csum_tcpudp_magic could be speeded up, and csum_fold as well */ | ||
2 | |||
3 | #ifndef _CRIS_CHECKSUM_H | ||
4 | #define _CRIS_CHECKSUM_H | ||
5 | |||
6 | #include <arch/checksum.h> | ||
7 | |||
8 | /* | ||
9 | * computes the checksum of a memory block at buff, length len, | ||
10 | * and adds in "sum" (32-bit) | ||
11 | * | ||
12 | * returns a 32-bit number suitable for feeding into itself | ||
13 | * or csum_tcpudp_magic | ||
14 | * | ||
15 | * this function must be called with even lengths, except | ||
16 | * for the last fragment, which may be odd | ||
17 | * | ||
18 | * it's best to have buff aligned on a 32-bit boundary | ||
19 | */ | ||
20 | __wsum csum_partial(const void *buff, int len, __wsum sum); | ||
21 | |||
22 | /* | ||
23 | * the same as csum_partial, but copies from src while it | ||
24 | * checksums | ||
25 | * | ||
26 | * here even more important to align src and dst on a 32-bit (or even | ||
27 | * better 64-bit) boundary | ||
28 | */ | ||
29 | |||
30 | __wsum csum_partial_copy_nocheck(const void *src, void *dst, | ||
31 | int len, __wsum sum); | ||
32 | |||
33 | /* | ||
34 | * Fold a partial checksum into a word | ||
35 | */ | ||
36 | |||
37 | static inline __sum16 csum_fold(__wsum csum) | ||
38 | { | ||
39 | u32 sum = (__force u32)csum; | ||
40 | sum = (sum & 0xffff) + (sum >> 16); /* add in end-around carry */ | ||
41 | sum = (sum & 0xffff) + (sum >> 16); /* add in end-around carry */ | ||
42 | return (__force __sum16)~sum; | ||
43 | } | ||
44 | |||
45 | extern __wsum csum_partial_copy_from_user(const void __user *src, void *dst, | ||
46 | int len, __wsum sum, | ||
47 | int *errptr); | ||
48 | |||
49 | /* | ||
50 | * This is a version of ip_compute_csum() optimized for IP headers, | ||
51 | * which always checksum on 4 octet boundaries. | ||
52 | * | ||
53 | */ | ||
54 | |||
55 | static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl) | ||
56 | { | ||
57 | return csum_fold(csum_partial(iph, ihl * 4, 0)); | ||
58 | } | ||
59 | |||
60 | /* | ||
61 | * computes the checksum of the TCP/UDP pseudo-header | ||
62 | * returns a 16-bit checksum, already complemented | ||
63 | */ | ||
64 | |||
65 | static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr, | ||
66 | unsigned short len, | ||
67 | unsigned short proto, | ||
68 | __wsum sum) | ||
69 | { | ||
70 | return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum)); | ||
71 | } | ||
72 | |||
73 | /* | ||
74 | * this routine is used for miscellaneous IP-like checksums, mainly | ||
75 | * in icmp.c | ||
76 | */ | ||
77 | |||
78 | static inline __sum16 ip_compute_csum(const void *buff, int len) | ||
79 | { | ||
80 | return csum_fold (csum_partial(buff, len, 0)); | ||
81 | } | ||
82 | |||
83 | #endif | ||