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/*
* linux/arch/sparc/mm/extable.c
*/
#include <linux/module.h>
#include <linux/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;
}
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