[linux-2.6-block.git] / include / linux / init.h

#ifndef _LINUX_INIT_H
#define _LINUX_INIT_H

#include <linux/compiler.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 between the variable name and equal
 * sign followed by value, e.g.:
 *
 * static int init_variable __initdata = 0;
 * static char linux_logo[] __initdata = { 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.
 * 
 * Also note, that this data cannot be "const".
 */

/* These are for everybody (although not all archs will actually
   discard it in modules) */
#define __init		__attribute__ ((__section__ (".init.text")))
#define __initdata	__attribute__ ((__section__ (".init.data")))
#define __exitdata	__attribute__ ((__section__(".exit.data")))
#define __exit_call	__attribute_used__ __attribute__ ((__section__ (".exitcall.exit")))

#ifdef MODULE
#define __exit		__attribute__ ((__section__(".exit.text")))
#else
#define __exit		__attribute_used__ __attribute__ ((__section__(".exit.text")))
#endif

/* For assembly routines */
#ifdef CONFIG_HOTPLUG_CPU
#define __INIT		.section	".text","ax"
#define __INITDATA	.section	".data","aw"
#else
#define __INIT		.section	".init.text","ax"
#define __INITDATA	.section	".init.data","aw"
#endif
#define __FINIT		.previous

#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[];

/* Defined in init/main.c */
extern char __initdata boot_command_line[];
extern char *saved_command_line;
extern unsigned int reset_devices;

/* used by init/main.c */
extern void setup_arch(char **);

#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(level,fn,id) \
	static initcall_t __initcall_##fn##id __attribute_used__ \
	__attribute__((__section__(".initcall" level ".init"))) = fn

/*
 * 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.
 */
#define pure_initcall(fn)		__define_initcall("0",fn,1)

#define core_initcall(fn)		__define_initcall("1",fn,1)
#define core_initcall_sync(fn)		__define_initcall("1s",fn,1s)
#define postcore_initcall(fn)		__define_initcall("2",fn,2)
#define postcore_initcall_sync(fn)	__define_initcall("2s",fn,2s)
#define arch_initcall(fn)		__define_initcall("3",fn,3)
#define arch_initcall_sync(fn)		__define_initcall("3s",fn,3s)
#define subsys_initcall(fn)		__define_initcall("4",fn,4)
#define subsys_initcall_sync(fn)	__define_initcall("4s",fn,4s)
#define fs_initcall(fn)			__define_initcall("5",fn,5)
#define fs_initcall_sync(fn)		__define_initcall("5s",fn,5s)
#define rootfs_initcall(fn)		__define_initcall("rootfs",fn,rootfs)
#define device_initcall(fn)		__define_initcall("6",fn,6)
#define device_initcall_sync(fn)	__define_initcall("6s",fn,6s)
#define late_initcall(fn)		__define_initcall("7",fn,7)
#define late_initcall_sync(fn)		__define_initcall("7s",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 \
	__attribute_used__ __attribute__((__section__(".con_initcall.init")))=fn

#define security_initcall(fn) \
	static initcall_t __initcall_##fn \
	__attribute_used__ __attribute__((__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 char __setup_str_##unique_id[] __initdata = str;	\
	static struct obs_kernel_param __setup_##unique_id	\
		__attribute_used__				\
		__attribute__((__section__(".init.setup")))	\
		__attribute__((aligned((sizeof(long)))))	\
		= { __setup_str_##unique_id, fn, early }

#define __setup_null_param(str, unique_id)			\
	__setup_param(str, unique_id, NULL, 0)

#define __setup(str, fn)					\
	__setup_param(str, fn, fn, 0)

#define __obsolete_setup(str)					\
	__setup_null_param(str, __LINE__)

/* 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);
#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 modules, but some people do... */
#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 device_initcall(fn)		module_init(fn)
#define late_initcall(fn)		module_init(fn)

#define security_initcall(fn)		module_init(fn)

/* These macros create a dummy inline: gcc 2.9x does not count alias
 as usage, hence the `unused function' warning when __init functions
 are declared static. We use the dummy __*_module_inline functions
 both to kill the warning and check the type of the init/cleanup
 function. */

/* Each module must use one module_init(), or one no_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_null_param(str, unique_id) 	/* nothing */
#define __setup(str, func) 			/* nothing */
#define __obsolete_setup(str) 			/* nothing */
#endif

/* Data marked not to be saved by software_suspend() */
#define __nosavedata __attribute__ ((__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
#else
#define __init_or_module __init
#define __initdata_or_module __initdata
#endif /*CONFIG_MODULES*/

#ifdef CONFIG_HOTPLUG
#define __devinit
#define __devinitdata
#define __devexit
#define __devexitdata
#else
#define __devinit __init
#define __devinitdata __initdata
#define __devexit __exit
#define __devexitdata __exitdata
#endif

#ifdef CONFIG_HOTPLUG_CPU
#define __cpuinit
#define __cpuinitdata
#define __cpuexit
#define __cpuexitdata
#else
#define __cpuinit	__init
#define __cpuinitdata __initdata
#define __cpuexit __exit
#define __cpuexitdata	__exitdata
#endif

#if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_ACPI_HOTPLUG_MEMORY) \
	|| defined(CONFIG_ACPI_HOTPLUG_MEMORY_MODULE)
#define __meminit
#define __meminitdata
#define __memexit
#define __memexitdata
#else
#define __meminit	__init
#define __meminitdata __initdata
#define __memexit __exit
#define __memexitdata	__exitdata
#endif

/* Functions marked as __devexit may be discarded at kernel link time, depending
   on config options.  Newer versions of binutils detect references from
   retained sections to discarded sections and flag an error.  Pointers to
   __devexit functions must use __devexit_p(function_name), the wrapper will
   insert either the function_name or NULL, depending on the config options.
 */
#if defined(MODULE) || defined(CONFIG_HOTPLUG)
#define __devexit_p(x) x
#else
#define __devexit_p(x) NULL
#endif

#ifdef MODULE
#define __exit_p(x) x
#else
#define __exit_p(x) NULL
#endif

#endif /* _LINUX_INIT_H */
Commit	Line	Data
1da177e4 LT	1	#ifndef _LINUX_INIT_H
	2	#define _LINUX_INIT_H
	3
1da177e4 LT	4	#include <linux/compiler.h>
	5
	6	/* These macros are used to mark some functions or
	7	* initialized data (doesn't apply to uninitialized data)
	8	* as `initialization' functions. The kernel can take this
	9	* as hint that the function is used only during the initialization
	10	* phase and free up used memory resources after
	11	*
	12	* Usage:
	13	* For functions:
	14	*
	15	* You should add __init immediately before the function name, like:
	16	*
	17	* static void __init initme(int x, int y)
	18	* {
	19	* extern int z; z = x * y;
	20	* }
	21	*
	22	* If the function has a prototype somewhere, you can also add
	23	* __init between closing brace of the prototype and semicolon:
	24	*
	25	* extern int initialize_foobar_device(int, int, int) __init;
	26	*
	27	* For initialized data:
	28	* You should insert __initdata between the variable name and equal
	29	* sign followed by value, e.g.:
	30	*
	31	* static int init_variable __initdata = 0;
	32	* static char linux_logo[] __initdata = { 0x32, 0x36, ... };
	33	*
	34	* Don't forget to initialize data not at file scope, i.e. within a function,
	35	* as gcc otherwise puts the data into the bss section and not into the init
	36	* section.
	37	*
	38	* Also note, that this data cannot be "const".
	39	*/
	40
	41	/* These are for everybody (although not all archs will actually
	42	discard it in modules) */
	43	#define __init __attribute__ ((__section__ (".init.text")))
	44	#define __initdata __attribute__ ((__section__ (".init.data")))
	45	#define __exitdata __attribute__ ((__section__(".exit.data")))
	46	#define __exit_call __attribute_used__ __attribute__ ((__section__ (".exitcall.exit")))
	47
	48	#ifdef MODULE
	49	#define __exit __attribute__ ((__section__(".exit.text")))
	50	#else
	51	#define __exit __attribute_used__ __attribute__ ((__section__(".exit.text")))
	52	#endif
	53
	54	/* For assembly routines */
86c0baf1 PB	55	#ifdef CONFIG_HOTPLUG_CPU
	56	#define __INIT .section ".text","ax"
	57	#define __INITDATA .section ".data","aw"
	58	#else
1da177e4	59	#define __INIT .section ".init.text","ax"
1da177e4	60	#define __INITDATA .section ".init.data","aw"
86c0baf1 PB	61	#endif
86c0baf1 PB	62	#define __FINIT .previous
1da177e4 LT	63
	64	#ifndef __ASSEMBLY__
	65	/*
	66	* Used for initialization calls..
	67	*/
	68	typedef int (*initcall_t)(void);
	69	typedef void (*exitcall_t)(void);
	70
	71	extern initcall_t __con_initcall_start[], __con_initcall_end[];
	72	extern initcall_t __security_initcall_start[], __security_initcall_end[];
	73
	74	/* Defined in init/main.c */
30d7e0d4 ABL	75	extern char __initdata boot_command_line[];
30d7e0d4 ABL	76	extern char *saved_command_line;
7e96287d	77	extern unsigned int reset_devices;
77d47582 AB	78
	79	/* used by init/main.c */
	80	extern void setup_arch(char **);
	81
1da177e4 LT	82	#endif
	83
	84	#ifndef MODULE
	85
	86	#ifndef __ASSEMBLY__
	87
	88	/* initcalls are now grouped by functionality into separate
	89	* subsections. Ordering inside the subsections is determined
	90	* by link order.
	91	* For backwards compatibility, initcall() puts the call in
	92	* the device init subsection.
735a7ffb AM	93	*
	94	* The `id' arg to __define_initcall() is needed so that multiple initcalls
	95	* can point at the same handler without causing duplicate-symbol build errors.
1da177e4 LT	96	*/
1da177e4 LT	97
735a7ffb AM	98	#define __define_initcall(level,fn,id) \
735a7ffb AM	99	static initcall_t __initcall_##fn##id __attribute_used__ \
1da177e4 LT	100	__attribute__((__section__(".initcall" level ".init"))) = fn
1da177e4 LT	101
b3438f82 LT	102	/*
	103	* A "pure" initcall has no dependencies on anything else, and purely
	104	* initializes variables that couldn't be statically initialized.
	105	*
	106	* This only exists for built-in code, not for modules.
	107	*/
	108	#define pure_initcall(fn) __define_initcall("0",fn,1)
	109
735a7ffb AM	110	#define core_initcall(fn) __define_initcall("1",fn,1)
	111	#define core_initcall_sync(fn) __define_initcall("1s",fn,1s)
	112	#define postcore_initcall(fn) __define_initcall("2",fn,2)
	113	#define postcore_initcall_sync(fn) __define_initcall("2s",fn,2s)
	114	#define arch_initcall(fn) __define_initcall("3",fn,3)
	115	#define arch_initcall_sync(fn) __define_initcall("3s",fn,3s)
	116	#define subsys_initcall(fn) __define_initcall("4",fn,4)
	117	#define subsys_initcall_sync(fn) __define_initcall("4s",fn,4s)
	118	#define fs_initcall(fn) __define_initcall("5",fn,5)
	119	#define fs_initcall_sync(fn) __define_initcall("5s",fn,5s)
8d610dd5	120	#define rootfs_initcall(fn) __define_initcall("rootfs",fn,rootfs)
735a7ffb AM	121	#define device_initcall(fn) __define_initcall("6",fn,6)
	122	#define device_initcall_sync(fn) __define_initcall("6s",fn,6s)
	123	#define late_initcall(fn) __define_initcall("7",fn,7)
	124	#define late_initcall_sync(fn) __define_initcall("7s",fn,7s)
1da177e4 LT	125
	126	#define __initcall(fn) device_initcall(fn)
	127
	128	#define __exitcall(fn) \
	129	static exitcall_t __exitcall_##fn __exit_call = fn
	130
	131	#define console_initcall(fn) \
	132	static initcall_t __initcall_##fn \
	133	__attribute_used__ __attribute__((__section__(".con_initcall.init")))=fn
	134
	135	#define security_initcall(fn) \
	136	static initcall_t __initcall_##fn \
	137	__attribute_used__ __attribute__((__section__(".security_initcall.init"))) = fn
	138
	139	struct obs_kernel_param {
	140	const char *str;
	141	int (setup_func)(char );
	142	int early;
	143	};
	144
	145	/*
	146	* Only for really core code. See moduleparam.h for the normal way.
	147	*
	148	* Force the alignment so the compiler doesn't space elements of the
	149	* obs_kernel_param "array" too far apart in .init.setup.
	150	*/
	151	#define __setup_param(str, unique_id, fn, early) \
	152	static char __setup_str_##unique_id[] __initdata = str; \
	153	static struct obs_kernel_param __setup_##unique_id \
	154	__attribute_used__ \
	155	__attribute__((__section__(".init.setup"))) \
	156	__attribute__((aligned((sizeof(long))))) \
	157	= { __setup_str_##unique_id, fn, early }
	158
	159	#define __setup_null_param(str, unique_id) \
	160	__setup_param(str, unique_id, NULL, 0)
	161
	162	#define __setup(str, fn) \
	163	__setup_param(str, fn, fn, 0)
	164
	165	#define __obsolete_setup(str) \
	166	__setup_null_param(str, __LINE__)
	167
	168	/* NOTE: fn is as per module_param, not __setup! Emits warning if fn
	169	* returns non-zero. */
	170	#define early_param(str, fn) \
	171	__setup_param(str, fn, fn, 1)
	172
30d7e0d4	173	/* Relies on boot_command_line being set */
1da177e4 LT	174	void __init parse_early_param(void);
	175	#endif /* __ASSEMBLY__ */
	176
	177	/**
	178	* module_init() - driver initialization entry point
	179	* @x: function to be run at kernel boot time or module insertion
	180	*
72fd4a35	181	* module_init() will either be called during do_initcalls() (if
1da177e4 LT	182	* builtin) or at module insertion time (if a module). There can only
	183	* be one per module.
	184	*/
	185	#define module_init(x) __initcall(x);
	186
	187	/**
	188	* module_exit() - driver exit entry point
	189	* @x: function to be run when driver is removed
	190	*
	191	* module_exit() will wrap the driver clean-up code
	192	* with cleanup_module() when used with rmmod when
	193	* the driver is a module. If the driver is statically
	194	* compiled into the kernel, module_exit() has no effect.
	195	* There can only be one per module.
	196	*/
	197	#define module_exit(x) __exitcall(x);
	198
	199	#else /* MODULE */
	200
	201	/* Don't use these in modules, but some people do... */
	202	#define core_initcall(fn) module_init(fn)
	203	#define postcore_initcall(fn) module_init(fn)
	204	#define arch_initcall(fn) module_init(fn)
	205	#define subsys_initcall(fn) module_init(fn)
	206	#define fs_initcall(fn) module_init(fn)
	207	#define device_initcall(fn) module_init(fn)
	208	#define late_initcall(fn) module_init(fn)
	209
	210	#define security_initcall(fn) module_init(fn)
	211
	212	/* These macros create a dummy inline: gcc 2.9x does not count alias
	213	as usage, hence the `unused function' warning when __init functions
	214	are declared static. We use the dummy __*_module_inline functions
	215	both to kill the warning and check the type of the init/cleanup
	216	function. */
	217
	218	/* Each module must use one module_init(), or one no_module_init */
	219	#define module_init(initfn) \
	220	static inline initcall_t __inittest(void) \
	221	{ return initfn; } \
	222	int init_module(void) __attribute__((alias(#initfn)));
	223
	224	/* This is only required if you want to be unloadable. */
	225	#define module_exit(exitfn) \
	226	static inline exitcall_t __exittest(void) \
	227	{ return exitfn; } \
	228	void cleanup_module(void) __attribute__((alias(#exitfn)));
	229
	230	#define __setup_param(str, unique_id, fn) /* nothing */
	231	#define __setup_null_param(str, unique_id) /* nothing */
	232	#define __setup(str, func) /* nothing */
	233	#define __obsolete_setup(str) /* nothing */
	234	#endif
	235
	236	/* Data marked not to be saved by software_suspend() */
	237	#define __nosavedata __attribute__ ((__section__ (".data.nosave")))
	238
	239	/* This means "can be init if no module support, otherwise module load
	240	may call it." */
	241	#ifdef CONFIG_MODULES
	242	#define __init_or_module
	243	#define __initdata_or_module
	244	#else
	245	#define __init_or_module __init
246	#define __initdata_or_module __initdata
247	#endif /CONFIG_MODULES/
248
249	#ifdef CONFIG_HOTPLUG
250	#define __devinit
251	#define __devinitdata
252	#define __devexit
253	#define __devexitdata
254	#else
255	#define __devinit __init
256	#define __devinitdata __initdata
257	#define __devexit __exit
258	#define __devexitdata __exitdata
259	#endif
260
e6982c67 AR	261	#ifdef CONFIG_HOTPLUG_CPU
	262	#define __cpuinit
	263	#define __cpuinitdata
	264	#define __cpuexit
	265	#define __cpuexitdata
	266	#else
	267	#define __cpuinit __init
	268	#define __cpuinitdata __initdata
	269	#define __cpuexit __exit
	270	#define __cpuexitdata __exitdata
	271	#endif
	272
9d99aaa3 AK	273	#if defined(CONFIG_MEMORY_HOTPLUG) \|\| defined(CONFIG_ACPI_HOTPLUG_MEMORY) \
9d99aaa3 AK	274	\|\| defined(CONFIG_ACPI_HOTPLUG_MEMORY_MODULE)
c09b4240 MT	275	#define __meminit
	276	#define __meminitdata
	277	#define __memexit
	278	#define __memexitdata
	279	#else
	280	#define __meminit __init
	281	#define __meminitdata __initdata
	282	#define __memexit __exit
	283	#define __memexitdata __exitdata
	284	#endif
	285
1da177e4 LT	286	/* Functions marked as __devexit may be discarded at kernel link time, depending
	287	on config options. Newer versions of binutils detect references from
	288	retained sections to discarded sections and flag an error. Pointers to
	289	__devexit functions must use __devexit_p(function_name), the wrapper will
	290	insert either the function_name or NULL, depending on the config options.
	291	*/
	292	#if defined(MODULE) \|\| defined(CONFIG_HOTPLUG)
	293	#define __devexit_p(x) x
	294	#else
	295	#define __devexit_p(x) NULL
	296	#endif
	297
	298	#ifdef MODULE
	299	#define __exit_p(x) x
	300	#else
	301	#define __exit_p(x) NULL
	302	#endif
	303
	304	#endif /* _LINUX_INIT_H */