include/linux/linkage.h

   1 #ifndef _LINUX_LINKAGE_H
   2 #define _LINUX_LINKAGE_H
   3
   4 #include <linux/compiler.h>
   5 #include <linux/stringify.h>
   6 #include <asm/linkage.h>
   7
   8 #ifdef __cplusplus
   9 #define CPP_ASMLINKAGE extern "C"
  10 #else
  11 #define CPP_ASMLINKAGE
  12 #endif
  13
  14 #ifndef asmlinkage
  15 #define asmlinkage CPP_ASMLINKAGE
  16 #endif
  17
  18 #ifdef CONFIG_SYMBOL_PREFIX
  19 #define __SYMBOL_NAME(x) CONFIG_SYMBOL_PREFIX __stringify(x)
  20 #else
  21 #define __SYMBOL_NAME(x) __stringify(x)
  22 #endif
  23
  24 #ifndef cond_syscall
  25 #define cond_syscall(x) asm(".weak\t" __SYMBOL_NAME(x) \
  26         "\n\t.set\t" __SYMBOL_NAME(x) "," __SYMBOL_NAME(sys_ni_syscall));
  27 #endif
  28
  29 #ifndef SYSCALL_ALIAS
  30 #define SYSCALL_ALIAS(alias, name)                              \
  31         asm ("\t.globl " __SYMBOL_NAME(alias)                   \
  32         "\n\t.set\t" __SYMBOL_NAME(alias) "," __SYMBOL_NAME(name))
  33 #endif
  34
  35 #define __page_aligned_data     __section(.data..page_aligned) __aligned(PAGE_SIZE)
  36 #define __page_aligned_bss      __section(.bss..page_aligned) __aligned(PAGE_SIZE)
  37
  38 /*
  39  * For assembly routines.
  40  *
  41  * Note when using these that you must specify the appropriate
  42  * alignment directives yourself
  43  */
  44 #define __PAGE_ALIGNED_DATA     .section ".data..page_aligned", "aw"
  45 #define __PAGE_ALIGNED_BSS      .section ".bss..page_aligned", "aw"
  46
  47 /*
  48  * This is used by architectures to keep arguments on the stack
  49  * untouched by the compiler by keeping them live until the end.
  50  * The argument stack may be owned by the assembly-language
  51  * caller, not the callee, and gcc doesn't always understand
  52  * that.
  53  *
  54  * We have the return value, and a maximum of six arguments.
  55  *
  56  * This should always be followed by a "return ret" for the
  57  * protection to work (ie no more work that the compiler might
  58  * end up needing stack temporaries for).
  59  */
  60 /* Assembly files may be compiled with -traditional .. */
  61 #ifndef __ASSEMBLY__
  62 #ifndef asmlinkage_protect
  63 # define asmlinkage_protect(n, ret, args...)    do { } while (0)
  64 #endif
  65 #endif
  66
  67 #ifndef __ALIGN
  68 #define __ALIGN         .align 4,0x90
  69 #define __ALIGN_STR     ".align 4,0x90"
  70 #endif
  71
  72 #ifdef __ASSEMBLY__
  73
  74 #ifndef LINKER_SCRIPT
  75 #define ALIGN __ALIGN
  76 #define ALIGN_STR __ALIGN_STR
  77
  78 #ifndef ENTRY
  79 #define ENTRY(name) \
  80   .globl name; \
  81   ALIGN; \
  82   name:
  83 #endif
  84 #endif /* LINKER_SCRIPT */
  85
  86 #ifndef WEAK
  87 #define WEAK(name)         \
  88         .weak name;        \
  89         name:
  90 #endif
  91
  92 #ifndef END
  93 #define END(name) \
  94   .size name, .-name
  95 #endif
  96
  97 /* If symbol 'name' is treated as a subroutine (gets called, and returns)
  98  * then please use ENDPROC to mark 'name' as STT_FUNC for the benefit of
  99  * static analysis tools such as stack depth analyzer.
 100  */
 101 #ifndef ENDPROC
 102 #define ENDPROC(name) \
 103   .type name, @function; \
 104   END(name)
 105 #endif
 106
 107 #endif
 108
 109 #endif