LXR linux/arch/ia64/include/asm/checksum.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef _ASM_IA64_CHECKSUM_H
   3#define _ASM_IA64_CHECKSUM_H
   4
   5/*
   6 * Modified 1998, 1999
   7 *      David Mosberger-Tang <davidm@hpl.hp.com>, Hewlett-Packard Co
   8 */
   9
  10/*
  11 * This is a version of ip_compute_csum() optimized for IP headers,
  12 * which always checksum on 4 octet boundaries.
  13 */
  14extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl);
  15
  16/*
  17 * Computes the checksum of the TCP/UDP pseudo-header returns a 16-bit
  18 * checksum, already complemented
  19 */
  20extern __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
  21                                 __u32 len, __u8 proto, __wsum sum);
  22
  23extern __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
  24                                 __u32 len, __u8 proto, __wsum sum);
  25
  26/*
  27 * Computes the checksum of a memory block at buff, length len,
  28 * and adds in "sum" (32-bit)
  29 *
  30 * returns a 32-bit number suitable for feeding into itself
  31 * or csum_tcpudp_magic
  32 *
  33 * this function must be called with even lengths, except
  34 * for the last fragment, which may be odd
  35 *
  36 * it's best to have buff aligned on a 32-bit boundary
  37 */
  38extern __wsum csum_partial(const void *buff, int len, __wsum sum);
  39
  40/*
  41 * This routine is used for miscellaneous IP-like checksums, mainly in
  42 * icmp.c
  43 */
  44extern __sum16 ip_compute_csum(const void *buff, int len);
  45
  46/*
  47 * Fold a partial checksum without adding pseudo headers.
  48 */
  49static inline __sum16 csum_fold(__wsum csum)
  50{
  51        u32 sum = (__force u32)csum;
  52        sum = (sum & 0xffff) + (sum >> 16);
  53        sum = (sum & 0xffff) + (sum >> 16);
  54        return (__force __sum16)~sum;
  55}
  56
  57#define _HAVE_ARCH_IPV6_CSUM    1
  58struct in6_addr;
  59extern __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
  60                               const struct in6_addr *daddr,
  61                               __u32 len, __u8 proto, __wsum csum);
  62
  63#endif /* _ASM_IA64_CHECKSUM_H */
  64