diff options
Diffstat (limited to 'include/linux/export.h')
| -rw-r--r-- | include/linux/export.h | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/include/linux/export.h b/include/linux/export.h new file mode 100644 index 000000000..a686fd0ba --- /dev/null +++ b/include/linux/export.h @@ -0,0 +1,96 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +#ifndef _LINUX_EXPORT_H +#define _LINUX_EXPORT_H + +#include <linux/compiler.h> +#include <linux/linkage.h> +#include <linux/stringify.h> + +/* + * This comment block is used by fixdep. Please do not remove. + * + * When CONFIG_MODVERSIONS is changed from n to y, all source files having + * EXPORT_SYMBOL variants must be re-compiled because genksyms is run as a + * side effect of the *.o build rule. + */ + +#ifdef CONFIG_64BIT +#define __EXPORT_SYMBOL_REF(sym) \ + .balign 8 ASM_NL \ + .quad sym +#else +#define __EXPORT_SYMBOL_REF(sym) \ + .balign 4 ASM_NL \ + .long sym +#endif + +/* + * LLVM integrated assembler cam merge adjacent string literals (like + * C and GNU-as) passed to '.ascii', but not to '.asciz' and chokes on: + * + * .asciz "MODULE_" "kvm" ; + */ +#define ___EXPORT_SYMBOL(sym, license, ns...) \ + .section ".export_symbol","a" ASM_NL \ + __export_symbol_##sym: ASM_NL \ + .asciz license ASM_NL \ + .ascii ns "\0" ASM_NL \ + __EXPORT_SYMBOL_REF(sym) ASM_NL \ + .previous + +#if defined(__DISABLE_EXPORTS) + +/* + * Allow symbol exports to be disabled completely so that C code may + * be reused in other execution contexts such as the UEFI stub or the + * decompressor. + */ +#define __EXPORT_SYMBOL(sym, license, ns) + +#elif defined(__GENKSYMS__) + +#define __EXPORT_SYMBOL(sym, license, ns) __GENKSYMS_EXPORT_SYMBOL(sym) + +#elif defined(__ASSEMBLY__) + +#define __EXPORT_SYMBOL(sym, license, ns) \ + ___EXPORT_SYMBOL(sym, license, ns) + +#else + +#ifdef CONFIG_GENDWARFKSYMS +/* + * With CONFIG_GENDWARFKSYMS, ensure the compiler emits debugging + * information for all exported symbols, including those defined in + * different TUs, by adding a __gendwarfksyms_ptr_<symbol> pointer + * that's discarded during the final link. + */ +#define __GENDWARFKSYMS_EXPORT(sym) \ + static typeof(sym) *__gendwarfksyms_ptr_##sym __used \ + __section(".discard.gendwarfksyms") = &sym; +#else +#define __GENDWARFKSYMS_EXPORT(sym) +#endif + +#define __EXPORT_SYMBOL(sym, license, ns) \ + extern typeof(sym) sym; \ + __ADDRESSABLE(sym) \ + __GENDWARFKSYMS_EXPORT(sym) \ + asm(__stringify(___EXPORT_SYMBOL(sym, license, ns))) + +#endif + +#ifdef DEFAULT_SYMBOL_NAMESPACE +#define _EXPORT_SYMBOL(sym, license) __EXPORT_SYMBOL(sym, license, DEFAULT_SYMBOL_NAMESPACE) +#else +#define _EXPORT_SYMBOL(sym, license) __EXPORT_SYMBOL(sym, license, "") +#endif + +#define EXPORT_SYMBOL(sym) _EXPORT_SYMBOL(sym, "") +#define EXPORT_SYMBOL_GPL(sym) _EXPORT_SYMBOL(sym, "GPL") +#define EXPORT_SYMBOL_NS(sym, ns) __EXPORT_SYMBOL(sym, "", ns) +#define EXPORT_SYMBOL_NS_GPL(sym, ns) __EXPORT_SYMBOL(sym, "GPL", ns) + +#define EXPORT_SYMBOL_FOR_MODULES(sym, mods) __EXPORT_SYMBOL(sym, "GPL", "module:" mods) + +#endif /* _LINUX_EXPORT_H */ |
