[net-next-2.6.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 */
#define __INIT		.section	".init.text","ax"
#define __FINIT		.previous
#define __INITDATA	.section	".init.data","aw"

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