106 lines
2.2 KiB
C
106 lines
2.2 KiB
C
/*
|
|
* linux/arch/sparc/mm/extable.c
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <asm/uaccess.h>
|
|
|
|
void sort_extable(struct exception_table_entry *start,
|
|
struct exception_table_entry *finish)
|
|
{
|
|
}
|
|
|
|
/* Caller knows they are in a range if ret->fixup == 0 */
|
|
const struct exception_table_entry *
|
|
search_extable(const struct exception_table_entry *start,
|
|
const struct exception_table_entry *last,
|
|
unsigned long value)
|
|
{
|
|
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
|
|
*
|
|
* Deleted entries are encoded as:
|
|
* word 1: unused
|
|
* word 2: -1
|
|
*
|
|
* See asm/uaccess.h for more details.
|
|
*/
|
|
|
|
/* 1. Try to find an exact match. */
|
|
for (walk = start; walk <= last; walk++) {
|
|
if (walk->fixup == 0) {
|
|
/* A range entry, skip both parts. */
|
|
walk++;
|
|
continue;
|
|
}
|
|
|
|
/* A deleted entry; see trim_init_extable */
|
|
if (walk->fixup == -1)
|
|
continue;
|
|
|
|
if (walk->insn == value)
|
|
return walk;
|
|
}
|
|
|
|
/* 2. Try to find a range match. */
|
|
for (walk = start; walk <= (last - 1); walk++) {
|
|
if (walk->fixup)
|
|
continue;
|
|
|
|
if (walk[0].insn <= value && walk[1].insn > value)
|
|
return walk;
|
|
|
|
walk++;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
#ifdef CONFIG_MODULES
|
|
/* We could memmove them around; easier to mark the trimmed ones. */
|
|
void trim_init_extable(struct module *m)
|
|
{
|
|
unsigned int i;
|
|
bool range;
|
|
|
|
for (i = 0; i < m->num_exentries; i += range ? 2 : 1) {
|
|
range = m->extable[i].fixup == 0;
|
|
|
|
if (within_module_init(m->extable[i].insn, m)) {
|
|
m->extable[i].fixup = -1;
|
|
if (range)
|
|
m->extable[i+1].fixup = -1;
|
|
}
|
|
if (range)
|
|
i++;
|
|
}
|
|
}
|
|
#endif /* CONFIG_MODULES */
|
|
|
|
/* Special extable search, which handles ranges. Returns fixup */
|
|
unsigned long search_extables_range(unsigned long addr, unsigned long *g2)
|
|
{
|
|
const struct exception_table_entry *entry;
|
|
|
|
entry = search_exception_tables(addr);
|
|
if (!entry)
|
|
return 0;
|
|
|
|
/* Inside range? Fix g2 and return correct fixup */
|
|
if (!entry->fixup) {
|
|
*g2 = (addr - entry->insn) / 4;
|
|
return (entry + 1)->fixup;
|
|
}
|
|
|
|
return entry->fixup;
|
|
}
|