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linux/arch/mn10300/lib/checksum.c
Mark Salter d6bb7a1ad3 mn10300: add cc clobbers to asm statements
gcc 4.2.1 for MN10300 is more agressive than the older gcc in
reordering/moving other insns between an insn that sets flags and an insn
that uses those flags.  This leads to trouble with asm statements which
are missing an explicit "cc" clobber.  This patch adds the explicit "cc"
clobber to asm statements which do indeed clobber the condition flags.

Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-01-11 09:34:10 -08:00

101 lines
2.3 KiB
C

/* MN10300 Optimised checksumming wrappers
*
* Copyright (C) 2007 Matsushita Electric Industrial Co., Ltd.
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public Licence
* as published by the Free Software Foundation; either version
* 2 of the Licence, or (at your option) any later version.
*/
#include <linux/module.h>
#include <linux/errno.h>
#include <asm/byteorder.h>
#include <asm/uaccess.h>
#include <asm/checksum.h>
#include "internal.h"
static inline unsigned short from32to16(__wsum sum)
{
asm(" add %1,%0 \n"
" addc 0xffff,%0 \n"
: "=r" (sum)
: "r" (sum << 16), "0" (sum & 0xffff0000)
: "cc"
);
return sum >> 16;
}
__sum16 ip_fast_csum(const void *iph, unsigned int ihl)
{
return ~do_csum(iph, ihl * 4);
}
EXPORT_SYMBOL(ip_fast_csum);
__wsum csum_partial(const void *buff, int len, __wsum sum)
{
__wsum result;
result = do_csum(buff, len);
result += sum;
if (sum > result)
result++;
return result;
}
EXPORT_SYMBOL(csum_partial);
__sum16 ip_compute_csum(const void *buff, int len)
{
return ~from32to16(do_csum(buff, len));
}
EXPORT_SYMBOL(ip_compute_csum);
__wsum csum_partial_copy(const void *src, void *dst, int len, __wsum sum)
{
copy_from_user(dst, src, len);
return csum_partial(dst, len, sum);
}
EXPORT_SYMBOL(csum_partial_copy);
__wsum csum_partial_copy_nocheck(const void *src, void *dst,
int len, __wsum sum)
{
sum = csum_partial(src, len, sum);
memcpy(dst, src, len);
return sum;
}
EXPORT_SYMBOL(csum_partial_copy_nocheck);
__wsum csum_partial_copy_from_user(const void *src, void *dst,
int len, __wsum sum,
int *err_ptr)
{
int missing;
missing = copy_from_user(dst, src, len);
if (missing) {
memset(dst + len - missing, 0, missing);
*err_ptr = -EFAULT;
}
return csum_partial(dst, len, sum);
}
EXPORT_SYMBOL(csum_partial_copy_from_user);
__wsum csum_and_copy_to_user(const void *src, void *dst,
int len, __wsum sum,
int *err_ptr)
{
int missing;
missing = copy_to_user(dst, src, len);
if (missing) {
memset(dst + len - missing, 0, missing);
*err_ptr = -EFAULT;
}
return csum_partial(src, len, sum);
}
EXPORT_SYMBOL(csum_and_copy_to_user);