#ifndef _LINUX_INIT_H
  #define _LINUX_INIT_H
  
  #include <linux/compiler.h>
  #include <linux/types.h>
  
  /* These macros are used to mark some functions or 
   * initialized data (doesn't apply to uninitialized data)
   * as `initialization' functions. The kernel can take this
   * as hint that the function is used only during the initialization
   * phase and free up used memory resources after
   *
   * Usage:
   * For functions:
   * 
   * You should add __init immediately before the function name, like:
   *
   * static void __init initme(int x, int y)
   * {
   *    extern int z; z = x * y;
   * }
   *
   * If the function has a prototype somewhere, you can also add
   * __init between closing brace of the prototype and semicolon:
   *
   * extern int initialize_foobar_device(int, int, int) __init;
   *
   * For initialized data:
   * You should insert __initdata or __initconst between the variable name
   * and equal sign followed by value, e.g.:
   *
   * static int init_variable __initdata = 0;
   * static const char linux_logo[] __initconst = { 0x32, 0x36, ... };
   *
   * Don't forget to initialize data not at file scope, i.e. within a function,
   * as gcc otherwise puts the data into the bss section and not into the init
   * section.
   */
  
  /* These are for everybody (although not all archs will actually
     discard it in modules) */
  #define __init		__section(.init.text) __cold notrace
  #define __initdata	__section(.init.data)
  #define __initconst	__constsection(.init.rodata)
  #define __exitdata	__section(.exit.data)
  #define __exit_call	__used __section(.exitcall.exit)
  
  /*
   * Some architecture have tool chains which do not handle rodata attributes
   * correctly. For those disable special sections for const, so that other
   * architectures can annotate correctly.
   */
  #ifdef CONFIG_BROKEN_RODATA
  #define __constsection(x)
  #else
  #define __constsection(x) __section(x)
  #endif
  
  /*
   * modpost check for section mismatches during the kernel build.
   * A section mismatch happens when there are references from a
   * code or data section to an init section (both code or data).
   * The init sections are (for most archs) discarded by the kernel
   * when early init has completed so all such references are potential bugs.
   * For exit sections the same issue exists.
   *
   * The following markers are used for the cases where the reference to
   * the *init / *exit section (code or data) is valid and will teach
   * modpost not to issue a warning.  Intended semantics is that a code or
   * data tagged __ref* can reference code or data from init section without
   * producing a warning (of course, no warning does not mean code is
   * correct, so optimally document why the __ref is needed and why it's OK).
   *
   * The markers follow same syntax rules as __init / __initdata.
   */
  #define __ref            __section(.ref.text) noinline
  #define __refdata        __section(.ref.data)
  #define __refconst       __constsection(.ref.rodata)
  
  /* compatibility defines */
  #define __init_refok     __ref
  #define __initdata_refok __refdata
  #define __exit_refok     __ref
  
  
  #ifdef MODULE
  #define __exitused
  #else
  #define __exitused  __used
  #endif
  
  #define __exit          __section(.exit.text) __exitused __cold notrace
  
  /* temporary, until all users are removed */
  #define __cpuinit
  #define __cpuinitdata
  #define __cpuinitconst
  #define __cpuexit
  #define __cpuexitdata
  #define __cpuexitconst
  
  /* Used for MEMORY_HOTPLUG */
  #define __meminit        __section(.meminit.text) __cold notrace
  #define __meminitdata    __section(.meminit.data)
  #define __meminitconst   __constsection(.meminit.rodata)
  #define __memexit        __section(.memexit.text) __exitused __cold notrace
  #define __memexitdata    __section(.memexit.data)
  #define __memexitconst   __constsection(.memexit.rodata)
  
  /* For assembly routines */
  #define __HEAD		.section	".head.text","ax"
  #define __INIT		.section	".init.text","ax"
  #define __FINIT		.previous
  
  #define __INITDATA	.section	".init.data","aw",%progbits
  #define __INITRODATA	.section	".init.rodata","a",%progbits
  #define __FINITDATA	.previous
  
  /* temporary, until all users are removed */
  #define __CPUINIT
  
  #define __MEMINIT        .section	".meminit.text", "ax"
  #define __MEMINITDATA    .section	".meminit.data", "aw"
  #define __MEMINITRODATA  .section	".meminit.rodata", "a"
  
  /* silence warnings when references are OK */
  #define __REF            .section       ".ref.text", "ax"
  #define __REFDATA        .section       ".ref.data", "aw"
  #define __REFCONST       .section       ".ref.rodata", "a"
  
  #ifndef __ASSEMBLY__
  /*
   * Used for initialization calls..
   */
  typedef int (*initcall_t)(void);
  typedef void (*exitcall_t)(void);
  
  extern initcall_t __con_initcall_start[], __con_initcall_end[];
  extern initcall_t __security_initcall_start[], __security_initcall_end[];
  
  /* Used for contructor calls. */
  typedef void (*ctor_fn_t)(void);
  
  /* Defined in init/main.c */
  extern int do_one_initcall(initcall_t fn);
  extern char __initdata boot_command_line[];
  extern char *saved_command_line;
  extern unsigned int reset_devices;
  
  /* used by init/main.c */
  void setup_arch(char **);
  void prepare_namespace(void);
  void __init load_default_modules(void);
  int __init init_rootfs(void);
  
  extern void (*late_time_init)(void);
  
  extern bool initcall_debug;
  
  #endif
    
  #ifndef MODULE
  
  #ifndef __ASSEMBLY__
  
  /* initcalls are now grouped by functionality into separate 
   * subsections. Ordering inside the subsections is determined
   * by link order. 
   * For backwards compatibility, initcall() puts the call in 
   * the device init subsection.
   *
   * The `id' arg to __define_initcall() is needed so that multiple initcalls
   * can point at the same handler without causing duplicate-symbol build errors.
   */
  
  #define __define_initcall(fn, id) \
  	static initcall_t __initcall_##fn##id __used \
  	__attribute__((__section__(".initcall" #id ".init"))) = fn
  
  /*
   * Early initcalls run before initializing SMP.
   *
   * Only for built-in code, not modules.
   */
  #define early_initcall(fn)		__define_initcall(fn, early)
  
  /*
   * A "pure" initcall has no dependencies on anything else, and purely
   * initializes variables that couldn't be statically initialized.
   *
   * This only exists for built-in code, not for modules.
   * Keep main.c:initcall_level_names[] in sync.
   */
  #define pure_initcall(fn)		__define_initcall(fn, 0)
  
  #define core_initcall(fn)		__define_initcall(fn, 1)
  #define core_initcall_sync(fn)		__define_initcall(fn, 1s)
  #define postcore_initcall(fn)		__define_initcall(fn, 2)
  #define postcore_initcall_sync(fn)	__define_initcall(fn, 2s)
  #define arch_initcall(fn)		__define_initcall(fn, 3)
  #define arch_initcall_sync(fn)		__define_initcall(fn, 3s)
  #define subsys_initcall(fn)		__define_initcall(fn, 4)
  #define subsys_initcall_sync(fn)	__define_initcall(fn, 4s)
  #define fs_initcall(fn)			__define_initcall(fn, 5)
  #define fs_initcall_sync(fn)		__define_initcall(fn, 5s)
  #define rootfs_initcall(fn)		__define_initcall(fn, rootfs)
  #define device_initcall(fn)		__define_initcall(fn, 6)
  #define device_initcall_sync(fn)	__define_initcall(fn, 6s)
  #define late_initcall(fn)		__define_initcall(fn, 7)
  #define late_initcall_sync(fn)		__define_initcall(fn, 7s)
  
  #define __initcall(fn) device_initcall(fn)
  
  #define __exitcall(fn) \
  	static exitcall_t __exitcall_##fn __exit_call = fn
  
  #define console_initcall(fn) \
  	static initcall_t __initcall_##fn \
  	__used __section(.con_initcall.init) = fn
  
  #define security_initcall(fn) \
  	static initcall_t __initcall_##fn \
  	__used __section(.security_initcall.init) = fn
  
  struct obs_kernel_param {
  	const char *str;
  	int (*setup_func)(char *);
  	int early;
  };
  
  /*
   * Only for really core code.  See moduleparam.h for the normal way.
   *
   * Force the alignment so the compiler doesn't space elements of the
   * obs_kernel_param "array" too far apart in .init.setup.
   */
  #define __setup_param(str, unique_id, fn, early)			\
  	static const char __setup_str_##unique_id[] __initconst	\
  		__aligned(1) = str; \
  	static struct obs_kernel_param __setup_##unique_id	\
  		__used __section(.init.setup)			\
  		__attribute__((aligned((sizeof(long)))))	\
  		= { __setup_str_##unique_id, fn, early }
  
  #define __setup(str, fn)					\
  	__setup_param(str, fn, fn, 0)
  
  /* NOTE: fn is as per module_param, not __setup!  Emits warning if fn
   * returns non-zero. */
  #define early_param(str, fn)					\
  	__setup_param(str, fn, fn, 1)
  
  /* Relies on boot_command_line being set */
  void __init parse_early_param(void);
  void __init parse_early_options(char *cmdline);
  #endif /* __ASSEMBLY__ */
  
  /**
   * module_init() - driver initialization entry point
   * @x: function to be run at kernel boot time or module insertion
   * 
   * module_init() will either be called during do_initcalls() (if
   * builtin) or at module insertion time (if a module).  There can only
   * be one per module.
   */
  #define module_init(x)	__initcall(x);
  
  /**
   * module_exit() - driver exit entry point
   * @x: function to be run when driver is removed
   * 
   * module_exit() will wrap the driver clean-up code
   * with cleanup_module() when used with rmmod when
   * the driver is a module.  If the driver is statically
   * compiled into the kernel, module_exit() has no effect.
   * There can only be one per module.
   */
  #define module_exit(x)	__exitcall(x);
  
  #else /* MODULE */
  
  /* Don't use these in loadable modules, but some people do... */
  #define early_initcall(fn)		module_init(fn)
  #define core_initcall(fn)		module_init(fn)
  #define postcore_initcall(fn)		module_init(fn)
  #define arch_initcall(fn)		module_init(fn)
  #define subsys_initcall(fn)		module_init(fn)
  #define fs_initcall(fn)			module_init(fn)
  #define rootfs_initcall(fn)		module_init(fn)
  #define device_initcall(fn)		module_init(fn)
  #define late_initcall(fn)		module_init(fn)
  
  #define console_initcall(fn)		module_init(fn)
  #define security_initcall(fn)		module_init(fn)
  
  /* Each module must use one module_init(). */
  #define module_init(initfn)					\
  	static inline initcall_t __inittest(void)		\
  	{ return initfn; }					\
  	int init_module(void) __attribute__((alias(#initfn)));
  
  /* This is only required if you want to be unloadable. */
  #define module_exit(exitfn)					\
  	static inline exitcall_t __exittest(void)		\
  	{ return exitfn; }					\
  	void cleanup_module(void) __attribute__((alias(#exitfn)));
  
  #define __setup_param(str, unique_id, fn)	/* nothing */
  #define __setup(str, func) 			/* nothing */
  #endif
  
  /* Data marked not to be saved by software suspend */
  #define __nosavedata __section(.data..nosave)
  
  /* This means "can be init if no module support, otherwise module load
     may call it." */
  #ifdef CONFIG_MODULES
  #define __init_or_module
  #define __initdata_or_module
  #define __initconst_or_module
  #define __INIT_OR_MODULE	.text
  #define __INITDATA_OR_MODULE	.data
  #define __INITRODATA_OR_MODULE	.section ".rodata","a",%progbits
  #else
  #define __init_or_module __init
  #define __initdata_or_module __initdata
  #define __initconst_or_module __initconst
  #define __INIT_OR_MODULE __INIT
  #define __INITDATA_OR_MODULE __INITDATA
  #define __INITRODATA_OR_MODULE __INITRODATA
  #endif /*CONFIG_MODULES*/
  
  #ifdef MODULE
  #define __exit_p(x) x
  #else
  #define __exit_p(x) NULL
  #endif
  
  #endif /* _LINUX_INIT_H */