/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_CHECKSUM_64_H
#define _ASM_X86_CHECKSUM_64_H



#include <linux/compiler.h>
#include <linux/uaccess.h>
#include <asm/byteorder.h>


static inline __sum16 csum_fold(__wsum sum)
{
	asm("  addl %1,%0\n"
	    "  adcl $0xffff,%0"
	    : "=r" (sum)
	    : "r" ((__force u32)sum << 16),
	      "0" ((__force u32)sum & 0xffff0000));
	return (__force __sum16)(~(__force u32)sum >> 16);
}




static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl)
{
	unsigned int sum;

	asm("  movl (%1), %0\n"
	    "  subl $4, %2\n"
	    "  jbe 2f\n"
	    "  addl 4(%1), %0\n"
	    "  adcl 8(%1), %0\n"
	    "  adcl 12(%1), %0\n"
	    "1: adcl 16(%1), %0\n"
	    "  lea 4(%1), %1\n"
	    "  decl %2\n"
	    "  jne	1b\n"
	    "  adcl $0, %0\n"
	    "  movl %0, %2\n"
	    "  shrl $16, %0\n"
	    "  addw %w2, %w0\n"
	    "  adcl $0, %0\n"
	    "  notl %0\n"
	    "2:"
	
	    : "=r" (sum), "=r" (iph), "=r" (ihl)
	    : "1" (iph), "2" (ihl)
	    : "memory");
	return (__force __sum16)sum;
}


static inline __wsum
csum_tcpudp_nofold(__be32 saddr, __be32 daddr, __u32 len,
		   __u8 proto, __wsum sum)
{
	asm("  addl %1, %0\n"
	    "  adcl %2, %0\n"
	    "  adcl %3, %0\n"
	    "  adcl $0, %0\n"
	    : "=r" (sum)
	    : "g" (daddr), "g" (saddr),
	      "g" ((len + proto)<<8), "0" (sum));
	return sum;
}



static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
					__u32 len, __u8 proto,
					__wsum sum)
{
	return csum_fold(csum_tcpudp_nofold(saddr, daddr, len, proto, sum));
}


extern __wsum csum_partial(const void *buff, int len, __wsum sum);


extern __visible __wsum csum_partial_copy_generic(const void *src, void *dst, int len);

extern __wsum csum_and_copy_from_user(const void __user *src, void *dst, int len);
extern __wsum csum_and_copy_to_user(const void *src, void __user *dst, int len);
extern __wsum csum_partial_copy_nocheck(const void *src, void *dst, int len);


extern __sum16 ip_compute_csum(const void *buff, int len);



struct in6_addr;

#define _HAVE_ARCH_IPV6_CSUM 1
extern __sum16
csum_ipv6_magic(const struct in6_addr *saddr, const struct in6_addr *daddr,
		__u32 len, __u8 proto, __wsum sum);

static inline unsigned add32_with_carry(unsigned a, unsigned b)
{
	asm("addl %2,%0\n\t"
	    "adcl $0,%0"
	    : "=r" (a)
	    : "0" (a), "rm" (b));
	return a;
}

#define HAVE_ARCH_CSUM_ADD
static inline __wsum csum_add(__wsum csum, __wsum addend)
{
	return (__force __wsum)add32_with_carry((__force unsigned)csum,
						(__force unsigned)addend);
}

#endif 
