1#ifndef _ASM_X86_JUMP_LABEL_H
2#define _ASM_X86_JUMP_LABEL_H
3
4#ifndef __ASSEMBLY__
5
6#include <linux/stringify.h>
7#include <linux/types.h>
8#include <asm/nops.h>
9#include <asm/asm.h>
10
11#define JUMP_LABEL_NOP_SIZE 5
12
13#ifdef CONFIG_X86_64
14# define STATIC_KEY_INIT_NOP P6_NOP5_ATOMIC
15#else
16# define STATIC_KEY_INIT_NOP GENERIC_NOP5_ATOMIC
17#endif
18
19static __always_inline bool arch_static_branch(struct static_key *key)
20{
21	asm_volatile_goto("1:"
22		".byte " __stringify(STATIC_KEY_INIT_NOP) "\n\t"
23		".pushsection __jump_table,  \"aw\" \n\t"
24		_ASM_ALIGN "\n\t"
25		_ASM_PTR "1b, %l[l_yes], %c0 \n\t"
26		".popsection \n\t"
27		: :  "i" (key) : : l_yes);
28	return false;
29l_yes:
30	return true;
31}
32
33#ifdef CONFIG_X86_64
34typedef u64 jump_label_t;
35#else
36typedef u32 jump_label_t;
37#endif
38
39struct jump_entry {
40	jump_label_t code;
41	jump_label_t target;
42	jump_label_t key;
43};
44
45#endif  /* __ASSEMBLY__ */
46#endif
47