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/*
* linux/arch/sparc/mm/extable.c
*/
#include <linux/config.h>
#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 unsigned long
search_one_table(const struct exception_table_entry *start,
const struct exception_table_entry *end,
unsigned long value, unsigned long *g2)
{
const struct exception_table_entry *walk;
/* Single insn entries are encoded as:
* word 1: insn address
* word 2: fixup code address
*
* Range entries are encoded as:
* word 1: first insn address
* word 2: 0
* word 3: last insn address + 4 bytes
* word 4: fixup code address
*
* See asm/uaccess.h for more details.
*/
/* 1. Try to find an exact match. */
for (walk = start; walk <= end; walk++) {
if (walk->fixup == 0) {
/* A range entry, skip both parts. */
walk++;
continue;
}
if (walk->insn == value)
return walk->fixup;
}
/* 2. Try to find a range match. */
for (walk = start; walk <= (end - 1); walk++) {
if (walk->fixup)
continue;
if (walk[0].insn <= value &&
walk[1].insn > value) {
*g2 = (value - walk[0].insn) / 4;
return walk[1].fixup;
}
walk++;
}
return 0;
}
extern spinlock_t modlist_lock;
unsigned long
search_exception_table(unsigned long addr, unsigned long *g2)
{
unsigned long ret = 0, flags;
#ifndef CONFIG_MODULES
/* There is only the kernel to search. */
ret = search_one_table(__start___ex_table,
__stop___ex_table-1, addr, g2);
return ret;
#else
/* The kernel is the last "module" -- no need to treat it special. */
struct module *mp;
spin_lock_irqsave(&modlist_lock, flags);
for (mp = module_list; mp != NULL; mp = mp->next) {
if (mp->ex_table_start == NULL || !(mp->flags & (MOD_RUNNING | MOD_INITIALIZING)))
continue;
ret = search_one_table(mp->ex_table_start,
mp->ex_table_end-1, addr, g2);
if (ret)
break;
}
spin_unlock_irqrestore(&modlist_lock, flags);
return ret;
#endif
}
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