Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1/* SPDX-License-Identifier: GPL-2.0-only */
2#ifndef _LINUX_EXPORT_H
3#define _LINUX_EXPORT_H
4
5#include <linux/compiler.h>
6#include <linux/linkage.h>
7#include <linux/stringify.h>
8
9/*
10 * This comment block is used by fixdep. Please do not remove.
11 *
12 * When CONFIG_MODVERSIONS is changed from n to y, all source files having
13 * EXPORT_SYMBOL variants must be re-compiled because genksyms is run as a
14 * side effect of the *.o build rule.
15 */
16
17#ifdef CONFIG_64BIT
18#define __EXPORT_SYMBOL_REF(sym) \
19 .balign 8 ASM_NL \
20 .quad sym
21#else
22#define __EXPORT_SYMBOL_REF(sym) \
23 .balign 4 ASM_NL \
24 .long sym
25#endif
26
27#define ___EXPORT_SYMBOL(sym, license, ns) \
28 .section ".export_symbol","a" ASM_NL \
29 __export_symbol_##sym: ASM_NL \
30 .asciz license ASM_NL \
31 .asciz ns ASM_NL \
32 __EXPORT_SYMBOL_REF(sym) ASM_NL \
33 .previous
34
35#if defined(__DISABLE_EXPORTS)
36
37/*
38 * Allow symbol exports to be disabled completely so that C code may
39 * be reused in other execution contexts such as the UEFI stub or the
40 * decompressor.
41 */
42#define __EXPORT_SYMBOL(sym, license, ns)
43
44#elif defined(__GENKSYMS__)
45
46#define __EXPORT_SYMBOL(sym, license, ns) __GENKSYMS_EXPORT_SYMBOL(sym)
47
48#elif defined(__ASSEMBLY__)
49
50#define __EXPORT_SYMBOL(sym, license, ns) \
51 ___EXPORT_SYMBOL(sym, license, ns)
52
53#else
54
55#ifdef CONFIG_GENDWARFKSYMS
56/*
57 * With CONFIG_GENDWARFKSYMS, ensure the compiler emits debugging
58 * information for all exported symbols, including those defined in
59 * different TUs, by adding a __gendwarfksyms_ptr_<symbol> pointer
60 * that's discarded during the final link.
61 */
62#define __GENDWARFKSYMS_EXPORT(sym) \
63 static typeof(sym) *__gendwarfksyms_ptr_##sym __used \
64 __section(".discard.gendwarfksyms") = &sym;
65#else
66#define __GENDWARFKSYMS_EXPORT(sym)
67#endif
68
69#define __EXPORT_SYMBOL(sym, license, ns) \
70 extern typeof(sym) sym; \
71 __ADDRESSABLE(sym) \
72 __GENDWARFKSYMS_EXPORT(sym) \
73 asm(__stringify(___EXPORT_SYMBOL(sym, license, ns)))
74
75#endif
76
77#ifdef DEFAULT_SYMBOL_NAMESPACE
78#define _EXPORT_SYMBOL(sym, license) __EXPORT_SYMBOL(sym, license, DEFAULT_SYMBOL_NAMESPACE)
79#else
80#define _EXPORT_SYMBOL(sym, license) __EXPORT_SYMBOL(sym, license, "")
81#endif
82
83#define EXPORT_SYMBOL(sym) _EXPORT_SYMBOL(sym, "")
84#define EXPORT_SYMBOL_GPL(sym) _EXPORT_SYMBOL(sym, "GPL")
85#define EXPORT_SYMBOL_NS(sym, ns) __EXPORT_SYMBOL(sym, "", ns)
86#define EXPORT_SYMBOL_NS_GPL(sym, ns) __EXPORT_SYMBOL(sym, "GPL", ns)
87
88#endif /* _LINUX_EXPORT_H */