root/arch/x86/um/asm/checksum_32.h
/*
 * Licensed under the GPL
 */

#ifndef __UM_SYSDEP_CHECKSUM_H
#define __UM_SYSDEP_CHECKSUM_H

static inline __sum16 ip_compute_csum(const void *buff, int len)
{
    return csum_fold (csum_partial(buff, len, 0));
}

#define _HAVE_ARCH_IPV6_CSUM
static __inline__ __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
                                          const struct in6_addr *daddr,
                                          __u32 len, __u8 proto,
                                          __wsum sum)
{
        __asm__(
                "addl 0(%1), %0         ;\n"
                "adcl 4(%1), %0         ;\n"
                "adcl 8(%1), %0         ;\n"
                "adcl 12(%1), %0        ;\n"
                "adcl 0(%2), %0         ;\n"
                "adcl 4(%2), %0         ;\n"
                "adcl 8(%2), %0         ;\n"
                "adcl 12(%2), %0        ;\n"
                "adcl %3, %0            ;\n"
                "adcl %4, %0            ;\n"
                "adcl $0, %0            ;\n"
                : "=&r" (sum)
                : "r" (saddr), "r" (daddr),
                  "r"(htonl(len)), "r"(htonl(proto)), "0"(sum));

        return csum_fold(sum);
}

#endif