60 lines
1.3 KiB
C
60 lines
1.3 KiB
C
/*
|
|
* jump label x86 support
|
|
*
|
|
* Copyright (C) 2009 Jason Baron <jbaron@redhat.com>
|
|
*
|
|
*/
|
|
#include <linux/jump_label.h>
|
|
#include <linux/memory.h>
|
|
#include <linux/uaccess.h>
|
|
#include <linux/module.h>
|
|
#include <linux/list.h>
|
|
#include <linux/jhash.h>
|
|
#include <linux/cpu.h>
|
|
#include <asm/kprobes.h>
|
|
#include <asm/alternative.h>
|
|
|
|
#ifdef HAVE_JUMP_LABEL
|
|
|
|
union jump_code_union {
|
|
char code[JUMP_LABEL_NOP_SIZE];
|
|
struct {
|
|
char jump;
|
|
int offset;
|
|
} __attribute__((packed));
|
|
};
|
|
|
|
static void __jump_label_transform(struct jump_entry *entry,
|
|
enum jump_label_type type,
|
|
void *(*poker)(void *, const void *, size_t))
|
|
{
|
|
union jump_code_union code;
|
|
|
|
if (type == JUMP_LABEL_ENABLE) {
|
|
code.jump = 0xe9;
|
|
code.offset = entry->target -
|
|
(entry->code + JUMP_LABEL_NOP_SIZE);
|
|
} else
|
|
memcpy(&code, ideal_nops[NOP_ATOMIC5], JUMP_LABEL_NOP_SIZE);
|
|
|
|
(*poker)((void *)entry->code, &code, JUMP_LABEL_NOP_SIZE);
|
|
}
|
|
|
|
void arch_jump_label_transform(struct jump_entry *entry,
|
|
enum jump_label_type type)
|
|
{
|
|
get_online_cpus();
|
|
mutex_lock(&text_mutex);
|
|
__jump_label_transform(entry, type, text_poke_smp);
|
|
mutex_unlock(&text_mutex);
|
|
put_online_cpus();
|
|
}
|
|
|
|
void arch_jump_label_transform_static(struct jump_entry *entry,
|
|
enum jump_label_type type)
|
|
{
|
|
__jump_label_transform(entry, type, text_poke_early);
|
|
}
|
|
|
|
#endif
|