include/asm-sh64/checksum.h

   1 #ifndef __ASM_SH64_CHECKSUM_H
   2 #define __ASM_SH64_CHECKSUM_H
   3
   4 /*
   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
   7  * for more details.
   8  *
   9  * include/asm-sh64/checksum.h
  10  *
  11  * Copyright (C) 2000, 2001  Paolo Alberelli
  12  *
  13  */
  14
  15 #include <asm/registers.h>
  16
  17 /*
  18  * computes the checksum of a memory block at buff, length len,
  19  * and adds in "sum" (32-bit)
  20  *
  21  * returns a 32-bit number suitable for feeding into itself
  22  * or csum_tcpudp_magic
  23  *
  24  * this function must be called with even lengths, except
  25  * for the last fragment, which may be odd
  26  *
  27  * it's best to have buff aligned on a 32-bit boundary
  28  */
  29 asmlinkage __wsum csum_partial(const void *buff, int len, __wsum sum);
  30
  31 /*
  32  *      Note: when you get a NULL pointer exception here this means someone
  33  *      passed in an incorrect kernel address to one of these functions.
  34  *
  35  *      If you use these functions directly please don't forget the
  36  *      access_ok().
  37  */
  38
  39
  40 __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len,
  41                                        __wsum sum);
  42
  43 __wsum csum_partial_copy_from_user(const void __user *src, void *dst,
  44                                          int len, __wsum sum, int *err_ptr);
  45
  46 static inline __sum16 csum_fold(__wsum csum)
  47 {
  48         u32 sum = (__force u32)csum;
  49         sum = (sum & 0xffff) + (sum >> 16);
  50         sum = (sum & 0xffff) + (sum >> 16);
  51         return (__force __sum16)~sum;
  52 }
  53
  54 __sum16 ip_fast_csum(const void *iph, unsigned int ihl);
  55
  56 __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
  57                                  unsigned short len, unsigned short proto,
  58                                  __wsum sum);
  59
  60 /*
  61  * computes the checksum of the TCP/UDP pseudo-header
  62  * returns a 16-bit checksum, already complemented
  63  */
  64 static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
  65                                                    unsigned short len,
  66                                                    unsigned short proto,
  67                                                    __wsum sum)
  68 {
  69         return csum_fold(csum_tcpudp_nofold(saddr,daddr,len,proto,sum));
  70 }
  71
  72 /*
  73  * this routine is used for miscellaneous IP-like checksums, mainly
  74  * in icmp.c
  75  */
  76 static inline __sum16 ip_compute_csum(const void *buff, int len)
  77 {
  78         return csum_fold(csum_partial(buff, len, 0));
  79 }
  80
  81 #endif /* __ASM_SH64_CHECKSUM_H */
  82