include/asm-generic/export.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 #ifndef __ASM_GENERIC_EXPORT_H
   3 #define __ASM_GENERIC_EXPORT_H
   4
   5 #ifndef KSYM_FUNC
   6 #define KSYM_FUNC(x) x
   7 #endif
   8 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
   9 #define KSYM_ALIGN 4
  10 #elif defined(CONFIG_64BIT)
  11 #define KSYM_ALIGN 8
  12 #else
  13 #define KSYM_ALIGN 4
  14 #endif
  15 #ifndef KCRC_ALIGN
  16 #define KCRC_ALIGN 4
  17 #endif
  18
  19 .macro __put, val, name
  20 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
  21         .long   \val - ., \name - ., 0
  22 #elif defined(CONFIG_64BIT)
  23         .quad   \val, \name, 0
  24 #else
  25         .long   \val, \name, 0
  26 #endif
  27 .endm
  28
  29 /*
  30  * note on .section use: we specify progbits since usage of the "M" (SHF_MERGE)
  31  * section flag requires it. Use '%progbits' instead of '@progbits' since the
  32  * former apparently works on all arches according to the binutils source.
  33  */
  34
  35 .macro ___EXPORT_SYMBOL name,val,sec
  36 #if defined(CONFIG_MODULES) && !defined(__DISABLE_EXPORTS)
  37         .section ___ksymtab\sec+\name,"a"
  38         .balign KSYM_ALIGN
  39 __ksymtab_\name:
  40         __put \val, __kstrtab_\name
  41         .previous
  42         .section __ksymtab_strings,"aMS",%progbits,1
  43 __kstrtab_\name:
  44         .asciz "\name"
  45         .previous
  46 #ifdef CONFIG_MODVERSIONS
  47         .section ___kcrctab\sec+\name,"a"
  48         .balign KCRC_ALIGN
  49 #if defined(CONFIG_MODULE_REL_CRCS)
  50         .long __crc_\name - .
  51 #else
  52         .long __crc_\name
  53 #endif
  54         .weak __crc_\name
  55         .previous
  56 #endif
  57 #endif
  58 .endm
  59
  60 #if defined(CONFIG_TRIM_UNUSED_KSYMS)
  61
  62 #include <linux/kconfig.h>
  63 #include <generated/autoksyms.h>
  64
  65 .macro __ksym_marker sym
  66         .section ".discard.ksym","a"
  67 __ksym_marker_\sym:
  68          .previous
  69 .endm
  70
  71 #define __EXPORT_SYMBOL(sym, val, sec)                          \
  72         __ksym_marker sym;                                      \
  73         __cond_export_sym(sym, val, sec, __is_defined(__KSYM_##sym))
  74 #define __cond_export_sym(sym, val, sec, conf)                  \
  75         ___cond_export_sym(sym, val, sec, conf)
  76 #define ___cond_export_sym(sym, val, sec, enabled)              \
  77         __cond_export_sym_##enabled(sym, val, sec)
  78 #define __cond_export_sym_1(sym, val, sec) ___EXPORT_SYMBOL sym, val, sec
  79 #define __cond_export_sym_0(sym, val, sec) /* nothing */
  80
  81 #else
  82 #define __EXPORT_SYMBOL(sym, val, sec) ___EXPORT_SYMBOL sym, val, sec
  83 #endif
  84
  85 #define EXPORT_SYMBOL(name)                                     \
  86         __EXPORT_SYMBOL(name, KSYM_FUNC(name),)
  87 #define EXPORT_SYMBOL_GPL(name)                                 \
  88         __EXPORT_SYMBOL(name, KSYM_FUNC(name), _gpl)
  89 #define EXPORT_DATA_SYMBOL(name)                                \
  90         __EXPORT_SYMBOL(name, name,)
  91 #define EXPORT_DATA_SYMBOL_GPL(name)                            \
  92         __EXPORT_SYMBOL(name, name,_gpl)
  93
  94 #endif