LXR linux/arch/um/include/init.h

   1#ifndef _LINUX_UML_INIT_H
   2#define _LINUX_UML_INIT_H
   3
   4/* These macros are used to mark some functions or
   5 * initialized data (doesn't apply to uninitialized data)
   6 * as `initialization' functions. The kernel can take this
   7 * as hint that the function is used only during the initialization
   8 * phase and free up used memory resources after
   9 *
  10 * Usage:
  11 * For functions:
  12 *
  13 * You should add __init immediately before the function name, like:
  14 *
  15 * static void __init initme(int x, int y)
  16 * {
  17 *    extern int z; z = x * y;
  18 * }
  19 *
  20 * If the function has a prototype somewhere, you can also add
  21 * __init between closing brace of the prototype and semicolon:
  22 *
  23 * extern int initialize_foobar_device(int, int, int) __init;
  24 *
  25 * For initialized data:
  26 * You should insert __initdata between the variable name and equal
  27 * sign followed by value, e.g.:
  28 *
  29 * static int init_variable __initdata = 0;
  30 * static char linux_logo[] __initdata = { 0x32, 0x36, ... };
  31 *
  32 * Don't forget to initialize data not at file scope, i.e. within a function,
  33 * as gcc otherwise puts the data into the bss section and not into the init
  34 * section.
  35 *
  36 * Also note, that this data cannot be "const".
  37 */
  38
  39#ifndef _LINUX_INIT_H
  40typedef int (*initcall_t)(void);
  41typedef void (*exitcall_t)(void);
  42
  43/* These are for everybody (although not all archs will actually
  44   discard it in modules) */
  45#define __init          __attribute__ ((__section__ (".init.text")))
  46#define __initdata      __attribute__ ((__section__ (".init.data")))
  47#define __exitdata      __attribute__ ((__section__(".exit.data")))
  48#define __exit_call     __attribute_used__ __attribute__ ((__section__ (".exitcall.exit")))
  49
  50#ifdef MODULE
  51#define __exit          __attribute__ ((__section__(".exit.text")))
  52#else
  53#define __exit          __attribute_used__ __attribute__ ((__section__(".exit.text")))
  54#endif
  55
  56#endif
  57
  58#ifndef MODULE
  59struct uml_param {
  60        const char *str;
  61        int (*setup_func)(char *, int *);
  62};
  63
  64extern initcall_t __uml_initcall_start, __uml_initcall_end;
  65extern initcall_t __uml_postsetup_start, __uml_postsetup_end;
  66extern const char *__uml_help_start, *__uml_help_end;
  67#endif
  68
  69#define __uml_initcall(fn)                                              \
  70        static initcall_t __uml_initcall_##fn __uml_init_call = fn
  71
  72#define __uml_exitcall(fn)                                              \
  73        static exitcall_t __uml_exitcall_##fn __uml_exit_call = fn
  74
  75extern struct uml_param __uml_setup_start, __uml_setup_end;
  76
  77#define __uml_postsetup(fn)                                             \
  78        static initcall_t __uml_postsetup_##fn __uml_postsetup_call = fn
  79
  80#define __non_empty_string(dummyname,string)                            \
  81        struct __uml_non_empty_string_struct_##dummyname                \
  82        {                                                               \
  83                char _string[sizeof(string)-2];                         \
  84        }
  85
  86#ifndef MODULE
  87#define __uml_setup(str, fn, help...)                                   \
  88        __non_empty_string(fn ##_setup, str);                           \
  89        __uml_help(fn, help);                                           \
  90        static char __uml_setup_str_##fn[] __initdata = str;            \
  91        static struct uml_param __uml_setup_##fn __uml_init_setup = { __uml_setup_str_##fn, fn }
  92#else
  93#define __uml_setup(str, fn, help...)                                   \
  94
  95#endif
  96
  97#define __uml_help(fn, help...)                                         \
  98        __non_empty_string(fn ##__help, help);                          \
  99        static char __uml_help_str_##fn[] __initdata = help;            \
 100        static const char *__uml_help_##fn __uml_setup_help = __uml_help_str_##fn
 101
 102/*
 103 * Mark functions and data as being only used at initialization
 104 * or exit time.
 105 */
 106#define __uml_init_setup        __attribute_used__ __attribute__ ((__section__ (".uml.setup.init")))
 107#define __uml_setup_help        __attribute_used__ __attribute__ ((__section__ (".uml.help.init")))
 108#define __uml_init_call         __attribute_used__ __attribute__ ((__section__ (".uml.initcall.init")))
 109#define __uml_postsetup_call    __attribute_used__ __attribute__ ((__section__ (".uml.postsetup.init")))
 110#define __uml_exit_call         __attribute_used__ __attribute__ ((__section__ (".uml.exitcall.exit")))
 111
 112#ifndef __KERNEL__
 113
 114#define __define_initcall(level,fn) \
 115        static initcall_t __initcall_##fn __attribute_used__ \
 116        __attribute__((__section__(".initcall" level ".init"))) = fn
 117
 118/* Userspace initcalls shouldn't depend on anything in the kernel, so we'll
 119 * make them run first.
 120 */
 121#define __initcall(fn) __define_initcall("1", fn)
 122
 123#define __exitcall(fn) static exitcall_t __exitcall_##fn __exit_call = fn
 124
 125#define __init_call     __attribute_used__ __attribute__ ((__section__ (".initcall.init")))
 126
 127#endif
 128
 129#endif /* _LINUX_UML_INIT_H */
 130
 131/*
 132 * Overrides for Emacs so that we follow Linus's tabbing style.
 133 * Emacs will notice this stuff at the end of the file and automatically
 134 * adjust the settings for this buffer only.  This must remain at the end
 135 * of the file.
 136 * ---------------------------------------------------------------------------
 137 * Local variables:
 138 * c-file-style: "linux"
 139 * End:
 140 */
 141