release/src-rt-6.x.4708/linux/linux-2.6.36/arch/ia64/include/asm/checksum.h

   1 #ifndef _ASM_IA64_CHECKSUM_H
   2 #define _ASM_IA64_CHECKSUM_H
   3
   4 /*
   5  * Modified 1998, 1999
   6  *      David Mosberger-Tang <davidm@hpl.hp.com>, Hewlett-Packard Co
   7  */
   8
   9 /*
  10  * This is a version of ip_compute_csum() optimized for IP headers,
  11  * which always checksum on 4 octet boundaries.
  12  */
  13 extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl);
  14
  15 /*
  16  * Computes the checksum of the TCP/UDP pseudo-header returns a 16-bit
  17  * checksum, already complemented
  18  */
  19 extern __sum16 csum_tcpudp_magic (__be32 saddr, __be32 daddr,
  20                                              unsigned short len,
  21                                              unsigned short proto,
  22                                              __wsum sum);
  23
  24 extern __wsum csum_tcpudp_nofold (__be32 saddr, __be32 daddr,
  25                                         unsigned short len,
  26                                         unsigned short proto,
  27                                         __wsum sum);
  28
  29 /*
  30  * Computes the checksum of a memory block at buff, length len,
  31  * and adds in "sum" (32-bit)
  32  *
  33  * returns a 32-bit number suitable for feeding into itself
  34  * or csum_tcpudp_magic
  35  *
  36  * this function must be called with even lengths, except
  37  * for the last fragment, which may be odd
  38  *
  39  * it's best to have buff aligned on a 32-bit boundary
  40  */
  41 extern __wsum csum_partial(const void *buff, int len, __wsum sum);
  42
  43 /*
  44  * Same as csum_partial, but copies from src while it checksums.
  45  *
  46  * Here it is even more important to align src and dst on a 32-bit (or
  47  * even better 64-bit) boundary.
  48  */
  49 extern __wsum csum_partial_copy_from_user(const void __user *src, void *dst,
  50                                                  int len, __wsum sum,
  51                                                  int *errp);
  52
  53 extern __wsum csum_partial_copy_nocheck(const void *src, void *dst,
  54                                                int len, __wsum sum);
  55
  56 /*
  57  * This routine is used for miscellaneous IP-like checksums, mainly in
  58  * icmp.c
  59  */
  60 extern __sum16 ip_compute_csum(const void *buff, int len);
  61
  62 /*
  63  * Fold a partial checksum without adding pseudo headers.
  64  */
  65 static inline __sum16 csum_fold(__wsum csum)
  66 {
  67         u32 sum = (__force u32)csum;
  68         sum = (sum & 0xffff) + (sum >> 16);
  69         sum = (sum & 0xffff) + (sum >> 16);
  70         return (__force __sum16)~sum;
  71 }
  72
  73 #define _HAVE_ARCH_IPV6_CSUM    1
  74 struct in6_addr;
  75 extern __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
  76         const struct in6_addr *daddr, __u32 len, unsigned short proto,
  77         __wsum csum);
  78
  79 #endif /* _ASM_IA64_CHECKSUM_H */