1#ifndef _ASM_S390_JUMP_LABEL_H
2#define _ASM_S390_JUMP_LABEL_H
3
4#ifndef __ASSEMBLY__
5
6#include <linux/types.h>
7
8#define JUMP_LABEL_NOP_SIZE 6
9#define JUMP_LABEL_NOP_OFFSET 2
10
11/*
12 * We use a brcl 0,2 instruction for jump labels at compile time so it
13 * can be easily distinguished from a hotpatch generated instruction.
14 */
15static __always_inline bool arch_static_branch(struct static_key *key, bool branch)
16{
17	asm_volatile_goto("0:	brcl 0,"__stringify(JUMP_LABEL_NOP_OFFSET)"\n"
18		".pushsection __jump_table, \"aw\"\n"
19		".balign 8\n"
20		".quad 0b, %l[label], %0\n"
21		".popsection\n"
22		: : "X" (&((char *)key)[branch]) : : label);
23
24	return false;
25label:
26	return true;
27}
28
29static __always_inline bool arch_static_branch_jump(struct static_key *key, bool branch)
30{
31	asm_volatile_goto("0:	brcl 15, %l[label]\n"
32		".pushsection __jump_table, \"aw\"\n"
33		".balign 8\n"
34		".quad 0b, %l[label], %0\n"
35		".popsection\n"
36		: : "X" (&((char *)key)[branch]) : : label);
37
38	return false;
39label:
40	return true;
41}
42
43typedef unsigned long jump_label_t;
44
45struct jump_entry {
46	jump_label_t code;
47	jump_label_t target;
48	jump_label_t key;
49};
50
51#endif  /* __ASSEMBLY__ */
52#endif
53