1 /* SPDX-License-Identifier: GPL-2.0-only */
2 #ifndef __ASM_GENERIC_EXPORT_H
3 #define __ASM_GENERIC_EXPORT_H
4 
5 /*
6  * This comment block is used by fixdep. Please do not remove.
7  *
8  * When CONFIG_MODVERSIONS is changed from n to y, all source files having
9  * EXPORT_SYMBOL variants must be re-compiled because genksyms is run as a
10  * side effect of the *.o build rule.
11  */
12 
13 #ifndef KSYM_FUNC
14 #define KSYM_FUNC(x) x
15 #endif
16 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
17 #define KSYM_ALIGN 4
18 #elif defined(CONFIG_64BIT)
19 #define KSYM_ALIGN 8
20 #else
21 #define KSYM_ALIGN 4
22 #endif
23 
24 .macro __put, val, name
25 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
26 	.long	\val - ., \name - ., 0
27 #elif defined(CONFIG_64BIT)
28 	.quad	\val, \name, 0
29 #else
30 	.long	\val, \name, 0
31 #endif
32 .endm
33 
34 /*
35  * note on .section use: we specify progbits since usage of the "M" (SHF_MERGE)
36  * section flag requires it. Use '%progbits' instead of '@progbits' since the
37  * former apparently works on all arches according to the binutils source.
38  */
39 
40 .macro ___EXPORT_SYMBOL name,val,sec
41 #if defined(CONFIG_MODULES) && !defined(__DISABLE_EXPORTS)
42 	.section ___ksymtab\sec+\name,"a"
43 	.balign KSYM_ALIGN
44 __ksymtab_\name:
45 	__put \val, __kstrtab_\name
46 	.previous
47 	.section __ksymtab_strings,"aMS",%progbits,1
48 __kstrtab_\name:
49 	.asciz "\name"
50 	.previous
51 #endif
52 .endm
53 
54 #if defined(CONFIG_TRIM_UNUSED_KSYMS)
55 
56 #include <linux/kconfig.h>
57 #include <generated/autoksyms.h>
58 
59 .macro __ksym_marker sym
60 	.section ".discard.ksym","a"
61 __ksym_marker_\sym:
62 	 .previous
63 .endm
64 
65 #define __EXPORT_SYMBOL(sym, val, sec)				\
66 	__ksym_marker sym;					\
67 	__cond_export_sym(sym, val, sec, __is_defined(__KSYM_##sym))
68 #define __cond_export_sym(sym, val, sec, conf)			\
69 	___cond_export_sym(sym, val, sec, conf)
70 #define ___cond_export_sym(sym, val, sec, enabled)		\
71 	__cond_export_sym_##enabled(sym, val, sec)
72 #define __cond_export_sym_1(sym, val, sec) ___EXPORT_SYMBOL sym, val, sec
73 #define __cond_export_sym_0(sym, val, sec) /* nothing */
74 
75 #else
76 #define __EXPORT_SYMBOL(sym, val, sec) ___EXPORT_SYMBOL sym, val, sec
77 #endif
78 
79 #define EXPORT_SYMBOL(name)					\
80 	__EXPORT_SYMBOL(name, KSYM_FUNC(name),)
81 #define EXPORT_SYMBOL_GPL(name) 				\
82 	__EXPORT_SYMBOL(name, KSYM_FUNC(name), _gpl)
83 #define EXPORT_DATA_SYMBOL(name)				\
84 	__EXPORT_SYMBOL(name, name,)
85 #define EXPORT_DATA_SYMBOL_GPL(name)				\
86 	__EXPORT_SYMBOL(name, name,_gpl)
87 
88 #endif
89