xref: /OK3568_Linux_fs/kernel/arch/arm64/include/asm/linkage.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun #ifndef __ASM_LINKAGE_H
2*4882a593Smuzhiyun #define __ASM_LINKAGE_H
3*4882a593Smuzhiyun 
4*4882a593Smuzhiyun #define __ALIGN		.align 2
5*4882a593Smuzhiyun #define __ALIGN_STR	".align 2"
6*4882a593Smuzhiyun 
7*4882a593Smuzhiyun #if defined(CONFIG_ARM64_BTI_KERNEL) && defined(__aarch64__)
8*4882a593Smuzhiyun 
9*4882a593Smuzhiyun /*
10*4882a593Smuzhiyun  * Since current versions of gas reject the BTI instruction unless we
11*4882a593Smuzhiyun  * set the architecture version to v8.5 we use the hint instruction
12*4882a593Smuzhiyun  * instead.
13*4882a593Smuzhiyun  */
14*4882a593Smuzhiyun #define BTI_C hint 34 ;
15*4882a593Smuzhiyun 
16*4882a593Smuzhiyun /*
17*4882a593Smuzhiyun  * When using in-kernel BTI we need to ensure that PCS-conformant assembly
18*4882a593Smuzhiyun  * functions have suitable annotations.  Override SYM_FUNC_START to insert
19*4882a593Smuzhiyun  * a BTI landing pad at the start of everything.
20*4882a593Smuzhiyun  */
21*4882a593Smuzhiyun #define SYM_FUNC_START(name)				\
22*4882a593Smuzhiyun 	SYM_START(name, SYM_L_GLOBAL, SYM_A_ALIGN)	\
23*4882a593Smuzhiyun 	BTI_C
24*4882a593Smuzhiyun 
25*4882a593Smuzhiyun #define SYM_FUNC_START_NOALIGN(name)			\
26*4882a593Smuzhiyun 	SYM_START(name, SYM_L_GLOBAL, SYM_A_NONE)	\
27*4882a593Smuzhiyun 	BTI_C
28*4882a593Smuzhiyun 
29*4882a593Smuzhiyun #define SYM_FUNC_START_LOCAL(name)			\
30*4882a593Smuzhiyun 	SYM_START(name, SYM_L_LOCAL, SYM_A_ALIGN)	\
31*4882a593Smuzhiyun 	BTI_C
32*4882a593Smuzhiyun 
33*4882a593Smuzhiyun #define SYM_FUNC_START_LOCAL_NOALIGN(name)		\
34*4882a593Smuzhiyun 	SYM_START(name, SYM_L_LOCAL, SYM_A_NONE)	\
35*4882a593Smuzhiyun 	BTI_C
36*4882a593Smuzhiyun 
37*4882a593Smuzhiyun #define SYM_FUNC_START_WEAK(name)			\
38*4882a593Smuzhiyun 	SYM_START(name, SYM_L_WEAK, SYM_A_ALIGN)	\
39*4882a593Smuzhiyun 	BTI_C
40*4882a593Smuzhiyun 
41*4882a593Smuzhiyun #define SYM_FUNC_START_WEAK_NOALIGN(name)		\
42*4882a593Smuzhiyun 	SYM_START(name, SYM_L_WEAK, SYM_A_NONE)		\
43*4882a593Smuzhiyun 	BTI_C
44*4882a593Smuzhiyun 
45*4882a593Smuzhiyun #endif
46*4882a593Smuzhiyun 
47*4882a593Smuzhiyun /*
48*4882a593Smuzhiyun  * Annotate a function as position independent, i.e., safe to be called before
49*4882a593Smuzhiyun  * the kernel virtual mapping is activated.
50*4882a593Smuzhiyun  */
51*4882a593Smuzhiyun #define SYM_FUNC_START_PI(x)			\
52*4882a593Smuzhiyun 		SYM_FUNC_START_ALIAS(__pi_##x);	\
53*4882a593Smuzhiyun 		SYM_FUNC_START(x)
54*4882a593Smuzhiyun 
55*4882a593Smuzhiyun #define SYM_FUNC_START_WEAK_PI(x)		\
56*4882a593Smuzhiyun 		SYM_FUNC_START_ALIAS(__pi_##x);	\
57*4882a593Smuzhiyun 		SYM_FUNC_START_WEAK(x)
58*4882a593Smuzhiyun 
59*4882a593Smuzhiyun #define SYM_FUNC_END_PI(x)			\
60*4882a593Smuzhiyun 		SYM_FUNC_END(x);		\
61*4882a593Smuzhiyun 		SYM_FUNC_END_ALIAS(__pi_##x)
62*4882a593Smuzhiyun 
63*4882a593Smuzhiyun #endif
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