projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 26a28fa4 AB |
1 | #ifndef __ASM_GENERIC_CHECKSUM_H |
| 2 | #define __ASM_GENERIC_CHECKSUM_H | |
| 3 | ||
| 4 | /* | |
| 5 | * computes the checksum of a memory block at buff, length len, | |
| 6 | * and adds in "sum" (32-bit) | |
| 7 | * | |
| 8 | * returns a 32-bit number suitable for feeding into itself | |
| 9 | * or csum_tcpudp_magic | |
| 10 | * | |
| 11 | * this function must be called with even lengths, except | |
| 12 | * for the last fragment, which may be odd | |
| 13 | * | |
| 14 | * it's best to have buff aligned on a 32-bit boundary | |
| 15 | */ | |
| 16 | extern __wsum csum_partial(const void *buff, int len, __wsum sum); | |
| 17 | ||
| 18 | /* | |
| 19 | * the same as csum_partial, but copies from src while it | |
| 20 | * checksums | |
| 21 | * | |
| 22 | * here even more important to align src and dst on a 32-bit (or even | |
| 23 | * better 64-bit) boundary | |
| 24 | */ | |
| 25 | extern __wsum csum_partial_copy(const void *src, void *dst, int len, __wsum sum); | |
| 26 | ||
| 27 | /* | |
| 28 | * the same as csum_partial_copy, but copies from user space. | |
| 29 | * | |
| 30 | * here even more important to align src and dst on a 32-bit (or even | |
| 31 | * better 64-bit) boundary | |
| 32 | */ | |
| 33 | extern __wsum csum_partial_copy_from_user(const void __user *src, void *dst, | |
| 34 | int len, __wsum sum, int *csum_err); | |
| 35 | ||
| 4e29198e | 36 | #ifndef csum_partial_copy_nocheck |
| 26a28fa4 AB |
37 | #define csum_partial_copy_nocheck(src, dst, len, sum) \ |
| 38 | csum_partial_copy((src), (dst), (len), (sum)) | |
| 4e29198e | 39 | #endif |
| 26a28fa4 | 40 | |
| 64e69073 | 41 | #ifndef ip_fast_csum |
| 26a28fa4 AB |
42 | /* |
| 43 | * This is a version of ip_compute_csum() optimized for IP headers, | |
| 44 | * which always checksum on 4 octet boundaries. | |
| 45 | */ | |
| 46 | extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl); | |
| 64e69073 | 47 | #endif |
| 26a28fa4 | 48 | |
| 64e69073 | 49 | #ifndef csum_fold |
| 26a28fa4 AB |
50 | /* |
| 51 | * Fold a partial checksum | |
| 52 | */ | |
| 53 | static inline __sum16 csum_fold(__wsum csum) | |
| 54 | { | |
| 55 | u32 sum = (__force u32)csum; | |
| 56 | sum = (sum & 0xffff) + (sum >> 16); | |
| 57 | sum = (sum & 0xffff) + (sum >> 16); | |
| 58 | return (__force __sum16)~sum; | |
| 59 | } | |
| 64e69073 | 60 | #endif |
| 26a28fa4 AB |
61 | |
| 62 | #ifndef csum_tcpudp_nofold | |
| 63 | /* | |
| 64 | * computes the checksum of the TCP/UDP pseudo-header | |
| 65 | * returns a 16-bit checksum, already complemented | |
| 66 | */ | |
| 67 | extern __wsum | |
| 01cfbad7 AD |
68 | csum_tcpudp_nofold(__be32 saddr, __be32 daddr, __u32 len, |
| 69 | __u8 proto, __wsum sum); | |
| 26a28fa4 AB |
70 | #endif |
| 71 | ||
| 4e29198e | 72 | #ifndef csum_tcpudp_magic |
| 26a28fa4 | 73 | static inline __sum16 |
| 01cfbad7 AD |
74 | csum_tcpudp_magic(__be32 saddr, __be32 daddr, __u32 len, |
| 75 | __u8 proto, __wsum sum) | |
| 26a28fa4 AB |
76 | { |
| 77 | return csum_fold(csum_tcpudp_nofold(saddr, daddr, len, proto, sum)); | |
| 78 | } | |
| 4e29198e | 79 | #endif |
| 26a28fa4 AB |
80 | |
| 81 | /* | |
| 82 | * this routine is used for miscellaneous IP-like checksums, mainly | |
| 83 | * in icmp.c | |
| 84 | */ | |
| 85 | extern __sum16 ip_compute_csum(const void *buff, int len); | |
| 86 | ||
| 87 | #endif /* __ASM_GENERIC_CHECKSUM_H */ |