/* 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);
|
