1 #ifndef __ASM_SH64_CHECKSUM_H
2 #define __ASM_SH64_CHECKSUM_H
5 * This file is subject to the terms and conditions of the GNU General Public
6 * License. See the file "COPYING" in the main directory of this archive
9 * include/asm-sh64/checksum.h
11 * Copyright (C) 2000, 2001 Paolo Alberelli
16 * computes the checksum of a memory block at buff, length len,
17 * and adds in "sum" (32-bit)
19 * returns a 32-bit number suitable for feeding into itself
20 * or csum_tcpudp_magic
22 * this function must be called with even lengths, except
23 * for the last fragment, which may be odd
25 * it's best to have buff aligned on a 32-bit boundary
27 asmlinkage __wsum csum_partial(const void *buff, int len, __wsum sum);
30 * Note: when you get a NULL pointer exception here this means someone
31 * passed in an incorrect kernel address to one of these functions.
33 * If you use these functions directly please don't forget the
38 __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len,
41 __wsum csum_partial_copy_from_user(const void __user *src, void *dst,
42 int len, __wsum sum, int *err_ptr);
44 static inline __sum16 csum_fold(__wsum csum)
46 u32 sum = (__force u32)csum;
47 sum = (sum & 0xffff) + (sum >> 16);
48 sum = (sum & 0xffff) + (sum >> 16);
49 return (__force __sum16)~sum;
52 __sum16 ip_fast_csum(const void *iph, unsigned int ihl);
54 __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
55 unsigned short len, unsigned short proto,
59 * computes the checksum of the TCP/UDP pseudo-header
60 * returns a 16-bit checksum, already complemented
62 static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
67 return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
71 * this routine is used for miscellaneous IP-like checksums, mainly
74 static inline __sum16 ip_compute_csum(const void *buff, int len)
76 return csum_fold(csum_partial(buff, len, 0));
79 #endif /* __ASM_SH64_CHECKSUM_H */