extable.c

来自「是关于linux2.5.1的完全源码」· C语言 代码 · 共 49 行

/*
 * linux/arch/ppc/mm/extable.c
 *
 * from linux/arch/i386/mm/extable.c
 *
 *      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.
 */

#include <linux/module.h>
#include <asm/uaccess.h>

extern const struct exception_table_entry __start___ex_table[];
extern const struct exception_table_entry __stop___ex_table[];

static inline unsigned long
search_one_table(const struct exception_table_entry *first,
		 const struct exception_table_entry *last,
		 unsigned long value)
{
        while (first <= last) {
		const struct exception_table_entry *mid;
		long diff;

		mid = (last - first) / 2 + first;
		diff = mid->insn - value;
                if (diff == 0)
                        return mid->fixup;
                else if (diff < 0)
                        first = mid+1;
                else
                        last = mid-1;
        }
        return 0;
}

unsigned long
search_exception_table(unsigned long addr)
{
	unsigned long ret;

	ret = search_one_table(__start___ex_table, __stop___ex_table-1, addr);
	if (ret) return ret;

	return 0;
}