xref: /OK3568_Linux_fs/kernel/arch/arm64/include/asm/jump_label.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0-only */
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * Copyright (C) 2013 Huawei Ltd.
4*4882a593Smuzhiyun  * Author: Jiang Liu <liuj97@gmail.com>
5*4882a593Smuzhiyun  *
6*4882a593Smuzhiyun  * Based on arch/arm/include/asm/jump_label.h
7*4882a593Smuzhiyun  */
8*4882a593Smuzhiyun #ifndef __ASM_JUMP_LABEL_H
9*4882a593Smuzhiyun #define __ASM_JUMP_LABEL_H
10*4882a593Smuzhiyun 
11*4882a593Smuzhiyun #ifndef __ASSEMBLY__
12*4882a593Smuzhiyun 
13*4882a593Smuzhiyun #include <linux/types.h>
14*4882a593Smuzhiyun #include <asm/insn.h>
15*4882a593Smuzhiyun 
16*4882a593Smuzhiyun #define JUMP_LABEL_NOP_SIZE		AARCH64_INSN_SIZE
17*4882a593Smuzhiyun 
arch_static_branch(struct static_key * key,bool branch)18*4882a593Smuzhiyun static __always_inline bool arch_static_branch(struct static_key *key,
19*4882a593Smuzhiyun 					       bool branch)
20*4882a593Smuzhiyun {
21*4882a593Smuzhiyun 	asm_volatile_goto(
22*4882a593Smuzhiyun 		"1:	nop					\n\t"
23*4882a593Smuzhiyun 		 "	.pushsection	__jump_table, \"aw\"	\n\t"
24*4882a593Smuzhiyun 		 "	.align		3			\n\t"
25*4882a593Smuzhiyun 		 "	.long		1b - ., %l[l_yes] - .	\n\t"
26*4882a593Smuzhiyun 		 "	.quad		%c0 - .			\n\t"
27*4882a593Smuzhiyun 		 "	.popsection				\n\t"
28*4882a593Smuzhiyun 		 :  :  "i"(&((char *)key)[branch]) :  : l_yes);
29*4882a593Smuzhiyun 
30*4882a593Smuzhiyun 	return false;
31*4882a593Smuzhiyun l_yes:
32*4882a593Smuzhiyun 	return true;
33*4882a593Smuzhiyun }
34*4882a593Smuzhiyun 
arch_static_branch_jump(struct static_key * key,bool branch)35*4882a593Smuzhiyun static __always_inline bool arch_static_branch_jump(struct static_key *key,
36*4882a593Smuzhiyun 						    bool branch)
37*4882a593Smuzhiyun {
38*4882a593Smuzhiyun 	asm_volatile_goto(
39*4882a593Smuzhiyun 		"1:	b		%l[l_yes]		\n\t"
40*4882a593Smuzhiyun 		 "	.pushsection	__jump_table, \"aw\"	\n\t"
41*4882a593Smuzhiyun 		 "	.align		3			\n\t"
42*4882a593Smuzhiyun 		 "	.long		1b - ., %l[l_yes] - .	\n\t"
43*4882a593Smuzhiyun 		 "	.quad		%c0 - .			\n\t"
44*4882a593Smuzhiyun 		 "	.popsection				\n\t"
45*4882a593Smuzhiyun 		 :  :  "i"(&((char *)key)[branch]) :  : l_yes);
46*4882a593Smuzhiyun 
47*4882a593Smuzhiyun 	return false;
48*4882a593Smuzhiyun l_yes:
49*4882a593Smuzhiyun 	return true;
50*4882a593Smuzhiyun }
51*4882a593Smuzhiyun 
52*4882a593Smuzhiyun #endif  /* __ASSEMBLY__ */
53*4882a593Smuzhiyun #endif	/* __ASM_JUMP_LABEL_H */
54