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awilliam
GitHub Repository: awilliam/linux-vfio
 Path: blob/master/arch/mn10300/include/asm/checksum.h
15126 views
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/* MN10300 Optimised checksumming code

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 *

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 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.

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 * Written by David Howells ([email protected])

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 *

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 * This program is free software; you can redistribute it and/or

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 * modify it under the terms of the GNU General Public Licence

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 * as published by the Free Software Foundation; either version

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 * 2 of the Licence, or (at your option) any later version.

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 */

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#ifndef _ASM_CHECKSUM_H

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#define _ASM_CHECKSUM_H

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

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extern __wsum csum_partial_copy_nocheck(const void *src, void *dst,

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					int len, __wsum sum);

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extern __wsum csum_partial_copy_from_user(const void *src, void *dst,

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					  int len, __wsum sum,

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					  int *err_ptr);

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extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl);

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

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

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#define csum_partial_copy_fromuser csum_partial_copy

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extern __wsum csum_partial_copy(const void *src, void *dst, int len,

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				__wsum sum);

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static inline __sum16 csum_fold(__wsum sum)

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{

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	asm(

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		"	add	%1,%0		\n"

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		"	addc	0xffff,%0	\n"

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		: "=r" (sum)

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		: "r" (sum << 16), "0" (sum & 0xffff0000)

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		: "cc"

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	    );

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	return (~sum) >> 16;

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}

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static inline __wsum csum_tcpudp_nofold(unsigned long saddr,

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					unsigned long daddr,

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					unsigned short len,

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					unsigned short proto,

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					__wsum sum)

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{

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	__wsum tmp;

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	tmp = (__wsum) ntohs(len) << 16;

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	tmp += (__wsum) proto << 8;

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	asm(

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		"	add	%1,%0		\n"

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		"	addc	%2,%0		\n"

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		"	addc	%3,%0		\n"

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		"	addc	0,%0		\n"

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		: "=r" (sum)

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		: "r" (daddr), "r"(saddr), "r"(tmp), "0"(sum)

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		: "cc"

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	    );

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	return sum;

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}

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/*

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 * computes the checksum of the TCP/UDP pseudo-header

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 * returns a 16-bit checksum, already complemented

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 */

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static inline __sum16 csum_tcpudp_magic(unsigned long saddr,

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					unsigned long daddr,

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					unsigned short len,

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					unsigned short proto,

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					__wsum sum)

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{

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	return csum_fold(csum_tcpudp_nofold(saddr, daddr, len, proto, sum));

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}

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#undef _HAVE_ARCH_IPV6_CSUM

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/*

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 *	Copy and checksum to user

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 */

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#define HAVE_CSUM_COPY_USER

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extern __wsum csum_and_copy_to_user(const void *src, void *dst, int len,

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				    __wsum sum, int *err_ptr);

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#endif /* _ASM_CHECKSUM_H */

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