Commit | Line | Data |
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1da177e4 LT |
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 <asm/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 | */ | |
3532010b | 20 | __wsum csum_partial(const void *buff, int len, __wsum sum); |
1da177e4 LT |
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 | ||
3532010b AV |
30 | __wsum csum_partial_copy_nocheck(const void *src, void *dst, |
31 | int len, __wsum sum); | |
1da177e4 LT |
32 | |
33 | /* | |
34 | * Fold a partial checksum into a word | |
35 | */ | |
36 | ||
3532010b | 37 | static inline __sum16 csum_fold(__wsum csum) |
1da177e4 | 38 | { |
3532010b AV |
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; | |
1da177e4 LT |
43 | } |
44 | ||
3532010b AV |
45 | extern __wsum csum_partial_copy_from_user(const void __user *src, void *dst, |
46 | int len, __wsum sum, | |
1da177e4 LT |
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 | ||
3532010b | 55 | static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl) |
1da177e4 LT |
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 | ||
b9569471 | 65 | static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr, |
1da177e4 LT |
66 | unsigned short len, |
67 | unsigned short proto, | |
3532010b | 68 | __wsum sum) |
1da177e4 LT |
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 | ||
3532010b AV |
78 | static inline __sum16 ip_compute_csum(const void *buff, int len) |
79 | { | |
1da177e4 LT |
80 | return csum_fold (csum_partial(buff, len, 0)); |
81 | } | |
82 | ||
83 | #endif |