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/*
* linux/arch/ppc/mm/extable.c
*
* from linux/arch/i386/mm/extable.c
*/
#include <linux/config.h>
#include <linux/module.h>
#include <asm/uaccess.h>
extern struct exception_table_entry __start___ex_table[];
extern struct exception_table_entry __stop___ex_table[];
/*
* The exception table needs to be sorted because we use the macros
* which put things into the exception table in a variety of segments
* such as the prep, pmac, chrp, etc. segments as well as the init
* segment and the main kernel text segment.
*/
static inline void
sort_ex_table(struct exception_table_entry *start,
struct exception_table_entry *finish)
{
struct exception_table_entry el, *p, *q;
/* insertion sort */
for (p = start + 1; p < finish; ++p) {
/* start .. p-1 is sorted */
if (p[0].insn < p[-1].insn) {
/* move element p down to its right place */
el = *p;
q = p;
do {
/* el comes before q[-1], move q[-1] up one */
q[0] = q[-1];
--q;
} while (q > start && el.insn < q[-1].insn);
*q = el;
}
}
}
void
sort_exception_table(void)
{
sort_ex_table(__start___ex_table, __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;
#ifndef CONFIG_MODULES
/* There is only the kernel to search. */
ret = search_one_table(__start___ex_table, __stop___ex_table-1, addr);
if (ret) return ret;
#else
/* The kernel is the last "module" -- no need to treat it special. */
struct module *mp;
for (mp = module_list; mp != NULL; mp = mp->next) {
if (mp->ex_table_start == NULL)
continue;
ret = search_one_table(mp->ex_table_start,
mp->ex_table_end - 1, addr);
if (ret)
return ret;
}
#endif
return 0;
}
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