1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _ASM_S390_JUMP_LABEL_H
3#define _ASM_S390_JUMP_LABEL_H
4
5#define HAVE_JUMP_LABEL_BATCH
6
7#ifndef __ASSEMBLY__
8
9#include <linux/types.h>
10#include <linux/stringify.h>
11
12#define JUMP_LABEL_NOP_SIZE 6
13
14#ifdef CONFIG_CC_IS_CLANG
15#define JUMP_LABEL_STATIC_KEY_CONSTRAINT "i"
16#elif __GNUC__ < 9
17#define JUMP_LABEL_STATIC_KEY_CONSTRAINT "X"
18#else
19#define JUMP_LABEL_STATIC_KEY_CONSTRAINT "jdd"
20#endif
21
22/*
23 * We use a brcl 0,<offset> instruction for jump labels so it
24 * can be easily distinguished from a hotpatch generated instruction.
25 */
26static __always_inline bool arch_static_branch(struct static_key *key, bool branch)
27{
28	asm goto("0:	brcl 0,%l[label]\n"
29			  ".pushsection __jump_table,\"aw\"\n"
30			  ".balign	8\n"
31			  ".long	0b-.,%l[label]-.\n"
32			  ".quad	%0+%1-.\n"
33			  ".popsection\n"
34			  : : JUMP_LABEL_STATIC_KEY_CONSTRAINT (key), "i" (branch) : : label);
35	return false;
36label:
37	return true;
38}
39
40static __always_inline bool arch_static_branch_jump(struct static_key *key, bool branch)
41{
42	asm goto("0:	brcl 15,%l[label]\n"
43			  ".pushsection __jump_table,\"aw\"\n"
44			  ".balign	8\n"
45			  ".long	0b-.,%l[label]-.\n"
46			  ".quad	%0+%1-.\n"
47			  ".popsection\n"
48			  : : JUMP_LABEL_STATIC_KEY_CONSTRAINT (key), "i" (branch) : : label);
49	return false;
50label:
51	return true;
52}
53
54#endif  /* __ASSEMBLY__ */
55#endif
56