blob: b987ab2c1541afb1866e11949c156e6b62c9b67c (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
|
/*
* Jump label s390 support
*
* Copyright IBM Corp. 2011
* Author(s): Jan Glauber <jang@linux.vnet.ibm.com>
*/
#include <linux/module.h>
#include <linux/uaccess.h>
#include <linux/stop_machine.h>
#include <linux/jump_label.h>
#include <asm/ipl.h>
#ifdef HAVE_JUMP_LABEL
struct insn {
u16 opcode;
s32 offset;
} __packed;
struct insn_args {
struct jump_entry *entry;
enum jump_label_type type;
};
static void __jump_label_transform(struct jump_entry *entry,
enum jump_label_type type)
{
struct insn insn;
int rc;
if (type == JUMP_LABEL_ENABLE) {
/* brcl 15,offset */
insn.opcode = 0xc0f4;
insn.offset = (entry->target - entry->code) >> 1;
} else {
/* brcl 0,0 */
insn.opcode = 0xc004;
insn.offset = 0;
}
rc = probe_kernel_write((void *)entry->code, &insn, JUMP_LABEL_NOP_SIZE);
WARN_ON_ONCE(rc < 0);
}
static int __sm_arch_jump_label_transform(void *data)
{
struct insn_args *args = data;
__jump_label_transform(args->entry, args->type);
return 0;
}
void arch_jump_label_transform(struct jump_entry *entry,
enum jump_label_type type)
{
struct insn_args args;
args.entry = entry;
args.type = type;
stop_machine(__sm_arch_jump_label_transform, &args, NULL);
}
void arch_jump_label_transform_static(struct jump_entry *entry,
enum jump_label_type type)
{
__jump_label_transform(entry, type);
}
#endif
|
