include/asm-generic/export.h

0001 /* SPDX-License-Identifier: GPL-2.0-only */
0002 #ifndef __ASM_GENERIC_EXPORT_H
0003 #define __ASM_GENERIC_EXPORT_H
0004
0005 /*
0006  * This comment block is used by fixdep. Please do not remove.
0007  *
0008  * When CONFIG_MODVERSIONS is changed from n to y, all source files having
0009  * EXPORT_SYMBOL variants must be re-compiled because genksyms is run as a
0010  * side effect of the *.o build rule.
0011  */
0012
0013 #ifndef KSYM_FUNC
0014 #define KSYM_FUNC(x) x
0015 #endif
0016 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
0017 #define KSYM_ALIGN 4
0018 #elif defined(CONFIG_64BIT)
0019 #define KSYM_ALIGN 8
0020 #else
0021 #define KSYM_ALIGN 4
0022 #endif
0023
0024 .macro __put, val, name
0025 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
0026     .long   \val - ., \name - ., 0
0027 #elif defined(CONFIG_64BIT)
0028     .quad   \val, \name, 0
0029 #else
0030     .long   \val, \name, 0
0031 #endif
0032 .endm
0033
0034 /*
0035  * note on .section use: we specify progbits since usage of the "M" (SHF_MERGE)
0036  * section flag requires it. Use '%progbits' instead of '@progbits' since the
0037  * former apparently works on all arches according to the binutils source.
0038  */
0039
0040 .macro ___EXPORT_SYMBOL name,val,sec
0041 #if defined(CONFIG_MODULES) && !defined(__DISABLE_EXPORTS)
0042     .section ___ksymtab\sec+\name,"a"
0043     .balign KSYM_ALIGN
0044 __ksymtab_\name:
0045     __put \val, __kstrtab_\name
0046     .previous
0047     .section __ksymtab_strings,"aMS",%progbits,1
0048 __kstrtab_\name:
0049     .asciz "\name"
0050     .previous
0051 #endif
0052 .endm
0053
0054 #if defined(CONFIG_TRIM_UNUSED_KSYMS)
0055
0056 #include <linux/kconfig.h>
0057 #include <generated/autoksyms.h>
0058
0059 .macro __ksym_marker sym
0060     .section ".discard.ksym","a"
0061 __ksym_marker_\sym:
0062      .previous
0063 .endm
0064
0065 #define __EXPORT_SYMBOL(sym, val, sec)              \
0066     __ksym_marker sym;                  \
0067     __cond_export_sym(sym, val, sec, __is_defined(__KSYM_##sym))
0068 #define __cond_export_sym(sym, val, sec, conf)          \
0069     ___cond_export_sym(sym, val, sec, conf)
0070 #define ___cond_export_sym(sym, val, sec, enabled)      \
0071     __cond_export_sym_##enabled(sym, val, sec)
0072 #define __cond_export_sym_1(sym, val, sec) ___EXPORT_SYMBOL sym, val, sec
0073 #define __cond_export_sym_0(sym, val, sec) /* nothing */
0074
0075 #else
0076 #define __EXPORT_SYMBOL(sym, val, sec) ___EXPORT_SYMBOL sym, val, sec
0077 #endif
0078
0079 #define EXPORT_SYMBOL(name)                 \
0080     __EXPORT_SYMBOL(name, KSYM_FUNC(name),)
0081 #define EXPORT_SYMBOL_GPL(name)                 \
0082     __EXPORT_SYMBOL(name, KSYM_FUNC(name), _gpl)
0083 #define EXPORT_DATA_SYMBOL(name)                \
0084     __EXPORT_SYMBOL(name, name,)
0085 #define EXPORT_DATA_SYMBOL_GPL(name)                \
0086     __EXPORT_SYMBOL(name, name,_gpl)
0087
0088 #endif