CooCenter-System-kernel/arch/score/lib/checksum_copy.c

/*
 * arch/score/lib/csum_partial_copy.c
 *
 * Score Processor version.
 *
 * Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
 *  Lennox Wu <lennox.wu@sunplusct.com>
 *  Chen Liqin <liqin.chen@sunplusct.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see the file COPYING, or write
 * to the Free Software Foundation, Inc.,
 * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include <net/checksum.h>

#include <asm/uaccess.h>

unsigned int csum_partial_copy(const char *src, char *dst,
				int len, unsigned int sum)
{
	sum = csum_partial(src, len, sum);
	memcpy(dst, src, len);

	return sum;
}

unsigned int csum_partial_copy_from_user(const char *src, char *dst,
					int len, unsigned int 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);