[linux-block.git] / include / linux / moduleparam.h

#ifndef _LINUX_MODULE_PARAMS_H
#define _LINUX_MODULE_PARAMS_H
/* (C) Copyright 2001, 2002 Rusty Russell IBM Corporation */
#include <linux/init.h>
#include <linux/stringify.h>
#include <linux/kernel.h>

/* You can override this manually, but generally this should match the
   module name. */
#ifdef MODULE
#define MODULE_PARAM_PREFIX /* empty */
#else
#define MODULE_PARAM_PREFIX KBUILD_MODNAME "."
#endif

/* Chosen so that structs with an unsigned long line up. */
#define MAX_PARAM_PREFIX_LEN (64 - sizeof(unsigned long))

#define ___module_cat(a,b) __mod_ ## a ## b
#define __module_cat(a,b) ___module_cat(a,b)
#ifdef MODULE
#define __MODULE_INFO(tag, name, info)					  \
static const char __module_cat(name,__LINE__)[]				  \
  __used __attribute__((section(".modinfo"), unused, aligned(1)))	  \
  = __stringify(tag) "=" info
#else  /* !MODULE */
/* This struct is here for syntactic coherency, it is not used */
#define __MODULE_INFO(tag, name, info)					  \
  struct __module_cat(name,__LINE__) {}
#endif
#define __MODULE_PARM_TYPE(name, _type)					  \
  __MODULE_INFO(parmtype, name##type, #name ":" _type)

struct kernel_param;

struct kernel_param_ops {
	/* Returns 0, or -errno.  arg is in kp->arg. */
	int (*set)(const char *val, const struct kernel_param *kp);
	/* Returns length written or -errno.  Buffer is 4k (ie. be short!) */
	int (*get)(char *buffer, const struct kernel_param *kp);
	/* Optional function to free kp->arg when module unloaded. */
	void (*free)(void *arg);
};

/* Flag bits for kernel_param.flags */
#define KPARAM_ISBOOL		2

struct kernel_param {
	const char *name;
	const struct kernel_param_ops *ops;
	u16 perm;
	u16 flags;
	union {
		void *arg;
		const struct kparam_string *str;
		const struct kparam_array *arr;
	};
};

/* Special one for strings we want to copy into */
struct kparam_string {
	unsigned int maxlen;
	char *string;
};

/* Special one for arrays */
struct kparam_array
{
	unsigned int max;
	unsigned int *num;
	const struct kernel_param_ops *ops;
	unsigned int elemsize;
	void *elem;
};

/**
 * module_param - typesafe helper for a module/cmdline parameter
 * @value: the variable to alter, and exposed parameter name.
 * @type: the type of the parameter
 * @perm: visibility in sysfs.
 *
 * @value becomes the module parameter, or (prefixed by KBUILD_MODNAME and a
 * ".") the kernel commandline parameter.  Note that - is changed to _, so
 * the user can use "foo-bar=1" even for variable "foo_bar".
 *
 * @perm is 0 if the the variable is not to appear in sysfs, or 0444
 * for world-readable, 0644 for root-writable, etc.  Note that if it
 * is writable, you may need to use kparam_block_sysfs_write() around
 * accesses (esp. charp, which can be kfreed when it changes).
 *
 * The @type is simply pasted to refer to a param_ops_##type and a
 * param_check_##type: for convenience many standard types are provided but
 * you can create your own by defining those variables.
 *
 * Standard types are:
 *	byte, short, ushort, int, uint, long, ulong
 *	charp: a character pointer
 *	bool: a bool, values 0/1, y/n, Y/N.
 *	invbool: the above, only sense-reversed (N = true).
 */
#define module_param(name, type, perm)				\
	module_param_named(name, name, type, perm)

/**
 * module_param_named - typesafe helper for a renamed module/cmdline parameter
 * @name: a valid C identifier which is the parameter name.
 * @value: the actual lvalue to alter.
 * @type: the type of the parameter
 * @perm: visibility in sysfs.
 *
 * Usually it's a good idea to have variable names and user-exposed names the
 * same, but that's harder if the variable must be non-static or is inside a
 * structure.  This allows exposure under a different name.
 */
#define module_param_named(name, value, type, perm)			   \
	param_check_##type(name, &(value));				   \
	module_param_cb(name, &param_ops_##type, &value, perm);		   \
	__MODULE_PARM_TYPE(name, #type)

/**
 * module_param_cb - general callback for a module/cmdline parameter
 * @name: a valid C identifier which is the parameter name.
 * @ops: the set & get operations for this parameter.
 * @perm: visibility in sysfs.
 *
 * The ops can have NULL set or get functions.
 */
#define module_param_cb(name, ops, arg, perm)				      \
	__module_param_call(MODULE_PARAM_PREFIX,			      \
			    name, ops, arg, __same_type((arg), bool *), perm)

/* On alpha, ia64 and ppc64 relocations to global data cannot go into
   read-only sections (which is part of respective UNIX ABI on these
   platforms). So 'const' makes no sense and even causes compile failures
   with some compilers. */
#if defined(CONFIG_ALPHA) || defined(CONFIG_IA64) || defined(CONFIG_PPC64)
#define __moduleparam_const
#else
#define __moduleparam_const const
#endif

/* This is the fundamental function for registering boot/module
   parameters. */
#define __module_param_call(prefix, name, ops, arg, isbool, perm)	\
	/* Default value instead of permissions? */			\
	static int __param_perm_check_##name __attribute__((unused)) =	\
	BUILD_BUG_ON_ZERO((perm) < 0 || (perm) > 0777 || ((perm) & 2))	\
	+ BUILD_BUG_ON_ZERO(sizeof(""prefix) > MAX_PARAM_PREFIX_LEN);	\
	static const char __param_str_##name[] = prefix #name;		\
	static struct kernel_param __moduleparam_const __param_##name	\
	__used								\
    __attribute__ ((unused,__section__ ("__param"),aligned(sizeof(void *)))) \
	= { __param_str_##name, ops, perm, isbool ? KPARAM_ISBOOL : 0,	\
	    { arg } }

/* Obsolete - use module_param_cb() */
#define module_param_call(name, set, get, arg, perm)			\
	static struct kernel_param_ops __param_ops_##name =		\
		 { (void *)set, (void *)get };				\
	__module_param_call(MODULE_PARAM_PREFIX,			\
			    name, &__param_ops_##name, arg,		\
			    __same_type(arg, bool *),			\
			    (perm) + sizeof(__check_old_set_param(set))*0)

/* We don't get oldget: it's often a new-style param_get_uint, etc. */
static inline int
__check_old_set_param(int (*oldset)(const char *, struct kernel_param *))
{
	return 0;
}

/**
 * kparam_block_sysfs_write - make sure a parameter isn't written via sysfs.
 * @name: the name of the parameter
 *
 * There's no point blocking write on a paramter that isn't writable via sysfs!
 */
#define kparam_block_sysfs_write(name)			\
	do {						\
		BUG_ON(!(__param_##name.perm & 0222));	\
		__kernel_param_lock();			\
	} while (0)

/**
 * kparam_unblock_sysfs_write - allows sysfs to write to a parameter again.
 * @name: the name of the parameter
 */
#define kparam_unblock_sysfs_write(name)		\
	do {						\
		BUG_ON(!(__param_##name.perm & 0222));	\
		__kernel_param_unlock();		\
	} while (0)

/**
 * kparam_block_sysfs_read - make sure a parameter isn't read via sysfs.
 * @name: the name of the parameter
 *
 * This also blocks sysfs writes.
 */
#define kparam_block_sysfs_read(name)			\
	do {						\
		BUG_ON(!(__param_##name.perm & 0444));	\
		__kernel_param_lock();			\
	} while (0)

/**
 * kparam_unblock_sysfs_read - allows sysfs to read a parameter again.
 * @name: the name of the parameter
 */
#define kparam_unblock_sysfs_read(name)			\
	do {						\
		BUG_ON(!(__param_##name.perm & 0444));	\
		__kernel_param_unlock();		\
	} while (0)

#ifdef CONFIG_SYSFS
extern void __kernel_param_lock(void);
extern void __kernel_param_unlock(void);
#else
static inline void __kernel_param_lock(void)
{
}
static inline void __kernel_param_unlock(void)
{
}
#endif

#ifndef MODULE
/**
 * core_param - define a historical core kernel parameter.
 * @name: the name of the cmdline and sysfs parameter (often the same as var)
 * @var: the variable
 * @type: the type of the parameter
 * @perm: visibility in sysfs
 *
 * core_param is just like module_param(), but cannot be modular and
 * doesn't add a prefix (such as "printk.").  This is for compatibility
 * with __setup(), and it makes sense as truly core parameters aren't
 * tied to the particular file they're in.
 */
#define core_param(name, var, type, perm)				\
	param_check_##type(name, &(var));				\
	__module_param_call("", name, &param_ops_##type,		\
			    &var, __same_type(var, bool), perm)
#endif /* !MODULE */

/**
 * module_param_string - a char array parameter
 * @name: the name of the parameter
 * @string: the string variable
 * @len: the maximum length of the string, incl. terminator
 * @perm: visibility in sysfs.
 *
 * This actually copies the string when it's set (unlike type charp).
 * @len is usually just sizeof(string).
 */
#define module_param_string(name, string, len, perm)			\
	static const struct kparam_string __param_string_##name		\
		= { len, string };					\
	__module_param_call(MODULE_PARAM_PREFIX, name,			\
			    &param_ops_string,				\
			    .str = &__param_string_##name, 0, perm);	\
	__MODULE_PARM_TYPE(name, "string")

/* Called on module insert or kernel boot */
extern int parse_args(const char *name,
		      char *args,
		      const struct kernel_param *params,
		      unsigned num,
		      int (*unknown)(char *param, char *val));

/* Called by module remove. */
#ifdef CONFIG_SYSFS
extern void destroy_params(const struct kernel_param *params, unsigned num);
#else
static inline void destroy_params(const struct kernel_param *params,
				  unsigned num)
{
}
#endif /* !CONFIG_SYSFS */

/* All the helper functions */
/* The macros to do compile-time type checking stolen from Jakub
   Jelinek, who IIRC came up with this idea for the 2.4 module init code. */
#define __param_check(name, p, type) \
	static inline type *__check_##name(void) { return(p); }

extern struct kernel_param_ops param_ops_byte;
extern int param_set_byte(const char *val, const struct kernel_param *kp);
extern int param_get_byte(char *buffer, const struct kernel_param *kp);
#define param_check_byte(name, p) __param_check(name, p, unsigned char)

extern struct kernel_param_ops param_ops_short;
extern int param_set_short(const char *val, const struct kernel_param *kp);
extern int param_get_short(char *buffer, const struct kernel_param *kp);
#define param_check_short(name, p) __param_check(name, p, short)

extern struct kernel_param_ops param_ops_ushort;
extern int param_set_ushort(const char *val, const struct kernel_param *kp);
extern int param_get_ushort(char *buffer, const struct kernel_param *kp);
#define param_check_ushort(name, p) __param_check(name, p, unsigned short)

extern struct kernel_param_ops param_ops_int;
extern int param_set_int(const char *val, const struct kernel_param *kp);
extern int param_get_int(char *buffer, const struct kernel_param *kp);
#define param_check_int(name, p) __param_check(name, p, int)

extern struct kernel_param_ops param_ops_uint;
extern int param_set_uint(const char *val, const struct kernel_param *kp);
extern int param_get_uint(char *buffer, const struct kernel_param *kp);
#define param_check_uint(name, p) __param_check(name, p, unsigned int)

extern struct kernel_param_ops param_ops_long;
extern int param_set_long(const char *val, const struct kernel_param *kp);
extern int param_get_long(char *buffer, const struct kernel_param *kp);
#define param_check_long(name, p) __param_check(name, p, long)

extern struct kernel_param_ops param_ops_ulong;
extern int param_set_ulong(const char *val, const struct kernel_param *kp);
extern int param_get_ulong(char *buffer, const struct kernel_param *kp);
#define param_check_ulong(name, p) __param_check(name, p, unsigned long)

extern struct kernel_param_ops param_ops_charp;
extern int param_set_charp(const char *val, const struct kernel_param *kp);
extern int param_get_charp(char *buffer, const struct kernel_param *kp);
#define param_check_charp(name, p) __param_check(name, p, char *)

/* For historical reasons "bool" parameters can be (unsigned) "int". */
extern struct kernel_param_ops param_ops_bool;
extern int param_set_bool(const char *val, const struct kernel_param *kp);
extern int param_get_bool(char *buffer, const struct kernel_param *kp);
#define param_check_bool(name, p)					\
	static inline void __check_##name(void)				\
	{								\
		BUILD_BUG_ON(!__same_type((p), bool *) &&		\
			     !__same_type((p), unsigned int *) &&	\
			     !__same_type((p), int *));			\
	}

extern struct kernel_param_ops param_ops_invbool;
extern int param_set_invbool(const char *val, const struct kernel_param *kp);
extern int param_get_invbool(char *buffer, const struct kernel_param *kp);
#define param_check_invbool(name, p) __param_check(name, p, bool)

/**
 * module_param_array - a parameter which is an array of some type
 * @name: the name of the array variable
 * @type: the type, as per module_param()
 * @nump: optional pointer filled in with the number written
 * @perm: visibility in sysfs
 *
 * Input and output are as comma-separated values.  Commas inside values
 * don't work properly (eg. an array of charp).
 *
 * ARRAY_SIZE(@name) is used to determine the number of elements in the
 * array, so the definition must be visible.
 */
#define module_param_array(name, type, nump, perm)		\
	module_param_array_named(name, name, type, nump, perm)

/**
 * module_param_array_named - renamed parameter which is an array of some type
 * @name: a valid C identifier which is the parameter name
 * @array: the name of the array variable
 * @type: the type, as per module_param()
 * @nump: optional pointer filled in with the number written
 * @perm: visibility in sysfs
 *
 * This exposes a different name than the actual variable name.  See
 * module_param_named() for why this might be necessary.
 */
#define module_param_array_named(name, array, type, nump, perm)		\
	static const struct kparam_array __param_arr_##name		\
	= { ARRAY_SIZE(array), nump, &param_ops_##type,			\
	    sizeof(array[0]), array };					\
	__module_param_call(MODULE_PARAM_PREFIX, name,			\
			    &param_array_ops,				\
			    .arr = &__param_arr_##name,			\
			    __same_type(array[0], bool), perm);		\
	__MODULE_PARM_TYPE(name, "array of " #type)

extern struct kernel_param_ops param_array_ops;

extern struct kernel_param_ops param_ops_string;
extern int param_set_copystring(const char *val, const struct kernel_param *);
extern int param_get_string(char *buffer, const struct kernel_param *kp);

/* for exporting parameters in /sys/parameters */

struct module;

#if defined(CONFIG_SYSFS) && defined(CONFIG_MODULES)
extern int module_param_sysfs_setup(struct module *mod,
				    const struct kernel_param *kparam,
				    unsigned int num_params);

extern void module_param_sysfs_remove(struct module *mod);
#else
static inline int module_param_sysfs_setup(struct module *mod,
			     const struct kernel_param *kparam,
			     unsigned int num_params)
{
	return 0;
}

static inline void module_param_sysfs_remove(struct module *mod)
{ }
#endif

#endif /* _LINUX_MODULE_PARAMS_H */
Commit	Line	Data
1da177e4 LT	1	#ifndef _LINUX_MODULE_PARAMS_H
	2	#define _LINUX_MODULE_PARAMS_H
	3	/* (C) Copyright 2001, 2002 Rusty Russell IBM Corporation */
	4	#include <linux/init.h>
	5	#include <linux/stringify.h>
	6	#include <linux/kernel.h>
	7
	8	/* You can override this manually, but generally this should match the
	9	module name. */
	10	#ifdef MODULE
	11	#define MODULE_PARAM_PREFIX /* empty */
	12	#else
367cb704	13	#define MODULE_PARAM_PREFIX KBUILD_MODNAME "."
1da177e4 LT	14	#endif
1da177e4 LT	15
730b69d2 RR	16	/* Chosen so that structs with an unsigned long line up. */
	17	#define MAX_PARAM_PREFIX_LEN (64 - sizeof(unsigned long))
	18
1da177e4 LT	19	#define ___module_cat(a,b) __mod_ ## a ## b
1da177e4 LT	20	#define __module_cat(a,b) ___module_cat(a,b)
b75be420	21	#ifdef MODULE
1da177e4 LT	22	#define __MODULE_INFO(tag, name, info) \
1da177e4 LT	23	static const char __module_cat(name,__LINE__)[] \
b6472776 JB	24	__used __attribute__((section(".modinfo"), unused, aligned(1))) \
b6472776 JB	25	= __stringify(tag) "=" info
1da177e4	26	#else /* !MODULE */
b75be420 LW	27	/* This struct is here for syntactic coherency, it is not used */
	28	#define __MODULE_INFO(tag, name, info) \
	29	struct __module_cat(name,__LINE__) {}
1da177e4 LT	30	#endif
	31	#define __MODULE_PARM_TYPE(name, _type) \
	32	__MODULE_INFO(parmtype, name##type, #name ":" _type)
	33
	34	struct kernel_param;
	35
9bbb9e5a RR	36	struct kernel_param_ops {
	37	/* Returns 0, or -errno. arg is in kp->arg. */
	38	int (set)(const char val, const struct kernel_param *kp);
	39	/* Returns length written or -errno. Buffer is 4k (ie. be short!) */
	40	int (get)(char buffer, const struct kernel_param *kp);
e6df34a4 RR	41	/* Optional function to free kp->arg when module unloaded. */
e6df34a4 RR	42	void (free)(void arg);
9bbb9e5a	43	};
1da177e4	44
45fcc70c	45	/* Flag bits for kernel_param.flags */
fddd5201	46	#define KPARAM_ISBOOL 2
45fcc70c	47
1da177e4 LT	48	struct kernel_param {
1da177e4 LT	49	const char *name;
9bbb9e5a	50	const struct kernel_param_ops *ops;
45fcc70c RR	51	u16 perm;
45fcc70c RR	52	u16 flags;
22e48eaf JB	53	union {
	54	void *arg;
	55	const struct kparam_string *str;
	56	const struct kparam_array *arr;
	57	};
1da177e4 LT	58	};
	59
	60	/* Special one for strings we want to copy into */
	61	struct kparam_string {
	62	unsigned int maxlen;
	63	char *string;
	64	};
	65
	66	/* Special one for arrays */
	67	struct kparam_array
	68	{
	69	unsigned int max;
	70	unsigned int *num;
9bbb9e5a	71	const struct kernel_param_ops *ops;
1da177e4 LT	72	unsigned int elemsize;
	73	void *elem;
	74	};
	75
546970bc RR	76	/**
	77	* module_param - typesafe helper for a module/cmdline parameter
	78	* @value: the variable to alter, and exposed parameter name.
	79	* @type: the type of the parameter
	80	* @perm: visibility in sysfs.
	81	*
	82	* @value becomes the module parameter, or (prefixed by KBUILD_MODNAME and a
	83	* ".") the kernel commandline parameter. Note that - is changed to _, so
	84	* the user can use "foo-bar=1" even for variable "foo_bar".
	85	*
	86	* @perm is 0 if the the variable is not to appear in sysfs, or 0444
	87	* for world-readable, 0644 for root-writable, etc. Note that if it
	88	* is writable, you may need to use kparam_block_sysfs_write() around
	89	* accesses (esp. charp, which can be kfreed when it changes).
	90	*
	91	* The @type is simply pasted to refer to a param_ops_##type and a
	92	* param_check_##type: for convenience many standard types are provided but
	93	* you can create your own by defining those variables.
	94	*
	95	* Standard types are:
	96	* byte, short, ushort, int, uint, long, ulong
	97	* charp: a character pointer
	98	* bool: a bool, values 0/1, y/n, Y/N.
	99	* invbool: the above, only sense-reversed (N = true).
	100	*/
	101	#define module_param(name, type, perm) \
	102	module_param_named(name, name, type, perm)
	103
	104	/**
	105	* module_param_named - typesafe helper for a renamed module/cmdline parameter
	106	* @name: a valid C identifier which is the parameter name.
	107	* @value: the actual lvalue to alter.
	108	* @type: the type of the parameter
	109	* @perm: visibility in sysfs.
	110	*
	111	* Usually it's a good idea to have variable names and user-exposed names the
	112	* same, but that's harder if the variable must be non-static or is inside a
	113	* structure. This allows exposure under a different name.
	114	*/
	115	#define module_param_named(name, value, type, perm) \
	116	param_check_##type(name, &(value)); \
	117	module_param_cb(name, &param_ops_##type, &value, perm); \
	118	__MODULE_PARM_TYPE(name, #type)
	119
	120	/**
	121	* module_param_cb - general callback for a module/cmdline parameter
	122	* @name: a valid C identifier which is the parameter name.
	123	* @ops: the set & get operations for this parameter.
	124	* @perm: visibility in sysfs.
	125	*
	126	* The ops can have NULL set or get functions.
	127	*/
	128	#define module_param_cb(name, ops, arg, perm) \
	129	__module_param_call(MODULE_PARAM_PREFIX, \
a6de51b2	130	name, ops, arg, __same_type((arg), bool *), perm)
546970bc	131
91d35dd9 IK	132	/* On alpha, ia64 and ppc64 relocations to global data cannot go into
	133	read-only sections (which is part of respective UNIX ABI on these
	134	platforms). So 'const' makes no sense and even causes compile failures
	135	with some compilers. */
	136	#if defined(CONFIG_ALPHA) \|\| defined(CONFIG_IA64) \|\| defined(CONFIG_PPC64)
	137	#define __moduleparam_const
	138	#else
	139	#define __moduleparam_const const
	140	#endif
	141
1da177e4	142	/* This is the fundamental function for registering boot/module
546970bc	143	parameters. */
9bbb9e5a	144	#define __module_param_call(prefix, name, ops, arg, isbool, perm) \
9774a1f5 AD	145	/* Default value instead of permissions? */ \
9774a1f5 AD	146	static int __param_perm_check_##name __attribute__((unused)) = \
730b69d2 RR	147	BUILD_BUG_ON_ZERO((perm) < 0 \|\| (perm) > 0777 \|\| ((perm) & 2)) \
730b69d2 RR	148	+ BUILD_BUG_ON_ZERO(sizeof(""prefix) > MAX_PARAM_PREFIX_LEN); \
22e48eaf	149	static const char __param_str_##name[] = prefix #name; \
91d35dd9	150	static struct kernel_param __moduleparam_const __param_##name \
3ff6eecc	151	__used \
1da177e4	152	__attribute__ ((unused,__section__ ("__param"),aligned(sizeof(void *)))) \
9bbb9e5a RR	153	= { __param_str_##name, ops, perm, isbool ? KPARAM_ISBOOL : 0, \
	154	{ arg } }
	155
	156	/* Obsolete - use module_param_cb() */
	157	#define module_param_call(name, set, get, arg, perm) \
	158	static struct kernel_param_ops __param_ops_##name = \
	159	{ (void )set, (void )get }; \
	160	__module_param_call(MODULE_PARAM_PREFIX, \
	161	name, &__param_ops_##name, arg, \
a6de51b2	162	__same_type(arg, bool *), \
9bbb9e5a RR	163	(perm) + sizeof(__check_old_set_param(set))*0)
	164
	165	/* We don't get oldget: it's often a new-style param_get_uint, etc. */
	166	static inline int
	167	__check_old_set_param(int (oldset)(const char , struct kernel_param *))
	168	{
	169	return 0;
	170	}
1da177e4	171
907b29eb RR	172	/**
	173	* kparam_block_sysfs_write - make sure a parameter isn't written via sysfs.
	174	* @name: the name of the parameter
	175	*
	176	* There's no point blocking write on a paramter that isn't writable via sysfs!
	177	*/
	178	#define kparam_block_sysfs_write(name) \
	179	do { \
	180	BUG_ON(!(__param_##name.perm & 0222)); \
	181	__kernel_param_lock(); \
	182	} while (0)
	183
	184	/**
	185	* kparam_unblock_sysfs_write - allows sysfs to write to a parameter again.
	186	* @name: the name of the parameter
	187	*/
	188	#define kparam_unblock_sysfs_write(name) \
	189	do { \
	190	BUG_ON(!(__param_##name.perm & 0222)); \
	191	__kernel_param_unlock(); \
	192	} while (0)
	193
	194	/**
	195	* kparam_block_sysfs_read - make sure a parameter isn't read via sysfs.
	196	* @name: the name of the parameter
	197	*
	198	* This also blocks sysfs writes.
	199	*/
	200	#define kparam_block_sysfs_read(name) \
	201	do { \
	202	BUG_ON(!(__param_##name.perm & 0444)); \
	203	__kernel_param_lock(); \
	204	} while (0)
	205
	206	/**
	207	* kparam_unblock_sysfs_read - allows sysfs to read a parameter again.
	208	* @name: the name of the parameter
	209	*/
	210	#define kparam_unblock_sysfs_read(name) \
	211	do { \
	212	BUG_ON(!(__param_##name.perm & 0444)); \
	213	__kernel_param_unlock(); \
	214	} while (0)
	215
	216	#ifdef CONFIG_SYSFS
	217	extern void __kernel_param_lock(void);
	218	extern void __kernel_param_unlock(void);
	219	#else
	220	static inline void __kernel_param_lock(void)
	221	{
	222	}
	223	static inline void __kernel_param_unlock(void)
	224	{
	225	}
	226	#endif
	227
67e67cea RR	228	#ifndef MODULE
	229	/**
	230	* core_param - define a historical core kernel parameter.
	231	* @name: the name of the cmdline and sysfs parameter (often the same as var)
	232	* @var: the variable
546970bc	233	* @type: the type of the parameter
67e67cea RR	234	* @perm: visibility in sysfs
	235	*
	236	* core_param is just like module_param(), but cannot be modular and
	237	* doesn't add a prefix (such as "printk."). This is for compatibility
	238	* with __setup(), and it makes sense as truly core parameters aren't
	239	* tied to the particular file they're in.
	240	*/
	241	#define core_param(name, var, type, perm) \
	242	param_check_##type(name, &(var)); \
9bbb9e5a	243	__module_param_call("", name, &param_ops_##type, \
fddd5201	244	&var, __same_type(var, bool), perm)
67e67cea RR	245	#endif /* !MODULE */
67e67cea RR	246
546970bc RR	247	/**
	248	* module_param_string - a char array parameter
	249	* @name: the name of the parameter
	250	* @string: the string variable
	251	* @len: the maximum length of the string, incl. terminator
	252	* @perm: visibility in sysfs.
	253	*
	254	* This actually copies the string when it's set (unlike type charp).
	255	* @len is usually just sizeof(string).
	256	*/
1da177e4	257	#define module_param_string(name, string, len, perm) \
22e48eaf	258	static const struct kparam_string __param_string_##name \
1da177e4	259	= { len, string }; \
fddd5201	260	__module_param_call(MODULE_PARAM_PREFIX, name, \
9bbb9e5a	261	&param_ops_string, \
fddd5201	262	.str = &__param_string_##name, 0, perm); \
1da177e4 LT	263	__MODULE_PARM_TYPE(name, "string")
	264
	265	/* Called on module insert or kernel boot */
	266	extern int parse_args(const char *name,
	267	char *args,
914dcaa8	268	const struct kernel_param *params,
1da177e4 LT	269	unsigned num,
	270	int (unknown)(char param, char *val));
	271
e180a6b7 RR	272	/* Called by module remove. */
	273	#ifdef CONFIG_SYSFS
	274	extern void destroy_params(const struct kernel_param *params, unsigned num);
	275	#else
	276	static inline void destroy_params(const struct kernel_param *params,
	277	unsigned num)
	278	{
	279	}
	280	#endif /* !CONFIG_SYSFS */
	281
1da177e4 LT	282	/* All the helper functions */
	283	/* The macros to do compile-time type checking stolen from Jakub
	284	Jelinek, who IIRC came up with this idea for the 2.4 module init code. */
	285	#define __param_check(name, p, type) \
	286	static inline type *__check_##name(void) { return(p); }
	287
9bbb9e5a RR	288	extern struct kernel_param_ops param_ops_byte;
	289	extern int param_set_byte(const char val, const struct kernel_param kp);
	290	extern int param_get_byte(char buffer, const struct kernel_param kp);
1da177e4 LT	291	#define param_check_byte(name, p) __param_check(name, p, unsigned char)
1da177e4 LT	292
9bbb9e5a RR	293	extern struct kernel_param_ops param_ops_short;
	294	extern int param_set_short(const char val, const struct kernel_param kp);
	295	extern int param_get_short(char buffer, const struct kernel_param kp);
1da177e4 LT	296	#define param_check_short(name, p) __param_check(name, p, short)
1da177e4 LT	297
9bbb9e5a RR	298	extern struct kernel_param_ops param_ops_ushort;
	299	extern int param_set_ushort(const char val, const struct kernel_param kp);
	300	extern int param_get_ushort(char buffer, const struct kernel_param kp);
1da177e4 LT	301	#define param_check_ushort(name, p) __param_check(name, p, unsigned short)
1da177e4 LT	302
9bbb9e5a RR	303	extern struct kernel_param_ops param_ops_int;
	304	extern int param_set_int(const char val, const struct kernel_param kp);
	305	extern int param_get_int(char buffer, const struct kernel_param kp);
1da177e4 LT	306	#define param_check_int(name, p) __param_check(name, p, int)
1da177e4 LT	307
9bbb9e5a RR	308	extern struct kernel_param_ops param_ops_uint;
	309	extern int param_set_uint(const char val, const struct kernel_param kp);
	310	extern int param_get_uint(char buffer, const struct kernel_param kp);
1da177e4 LT	311	#define param_check_uint(name, p) __param_check(name, p, unsigned int)
1da177e4 LT	312
9bbb9e5a RR	313	extern struct kernel_param_ops param_ops_long;
	314	extern int param_set_long(const char val, const struct kernel_param kp);
	315	extern int param_get_long(char buffer, const struct kernel_param kp);
1da177e4 LT	316	#define param_check_long(name, p) __param_check(name, p, long)
1da177e4 LT	317
9bbb9e5a RR	318	extern struct kernel_param_ops param_ops_ulong;
	319	extern int param_set_ulong(const char val, const struct kernel_param kp);
	320	extern int param_get_ulong(char buffer, const struct kernel_param kp);
1da177e4 LT	321	#define param_check_ulong(name, p) __param_check(name, p, unsigned long)
1da177e4 LT	322
9bbb9e5a RR	323	extern struct kernel_param_ops param_ops_charp;
	324	extern int param_set_charp(const char val, const struct kernel_param kp);
	325	extern int param_get_charp(char buffer, const struct kernel_param kp);
1da177e4 LT	326	#define param_check_charp(name, p) __param_check(name, p, char *)
1da177e4 LT	327
fddd5201	328	/* For historical reasons "bool" parameters can be (unsigned) "int". */
9bbb9e5a RR	329	extern struct kernel_param_ops param_ops_bool;
	330	extern int param_set_bool(const char val, const struct kernel_param kp);
	331	extern int param_get_bool(char buffer, const struct kernel_param kp);
fddd5201 RR	332	#define param_check_bool(name, p) \
	333	static inline void __check_##name(void) \
	334	{ \
a6de51b2 RR	335	BUILD_BUG_ON(!__same_type((p), bool *) && \
	336	!__same_type((p), unsigned int *) && \
	337	!__same_type((p), int *)); \
fddd5201	338	}
1da177e4	339
9bbb9e5a RR	340	extern struct kernel_param_ops param_ops_invbool;
	341	extern int param_set_invbool(const char val, const struct kernel_param kp);
	342	extern int param_get_invbool(char buffer, const struct kernel_param kp);
9a71af2c	343	#define param_check_invbool(name, p) __param_check(name, p, bool)
1da177e4	344
546970bc RR	345	/**
	346	* module_param_array - a parameter which is an array of some type
	347	* @name: the name of the array variable
	348	* @type: the type, as per module_param()
	349	* @nump: optional pointer filled in with the number written
	350	* @perm: visibility in sysfs
	351	*
	352	* Input and output are as comma-separated values. Commas inside values
	353	* don't work properly (eg. an array of charp).
	354	*
	355	* ARRAY_SIZE(@name) is used to determine the number of elements in the
	356	* array, so the definition must be visible.
	357	*/
	358	#define module_param_array(name, type, nump, perm) \
	359	module_param_array_named(name, name, type, nump, perm)
	360
	361	/**
	362	* module_param_array_named - renamed parameter which is an array of some type
	363	* @name: a valid C identifier which is the parameter name
	364	* @array: the name of the array variable
	365	* @type: the type, as per module_param()
	366	* @nump: optional pointer filled in with the number written
	367	* @perm: visibility in sysfs
	368	*
	369	* This exposes a different name than the actual variable name. See
	370	* module_param_named() for why this might be necessary.
	371	*/
1da177e4	372	#define module_param_array_named(name, array, type, nump, perm) \
22e48eaf	373	static const struct kparam_array __param_arr_##name \
9bbb9e5a	374	= { ARRAY_SIZE(array), nump, &param_ops_##type, \
1da177e4	375	sizeof(array[0]), array }; \
fddd5201	376	__module_param_call(MODULE_PARAM_PREFIX, name, \
9bbb9e5a	377	&param_array_ops, \
fddd5201 RR	378	.arr = &__param_arr_##name, \
fddd5201 RR	379	__same_type(array[0], bool), perm); \
1da177e4 LT	380	__MODULE_PARM_TYPE(name, "array of " #type)
1da177e4 LT	381
9bbb9e5a	382	extern struct kernel_param_ops param_array_ops;
1da177e4	383
9bbb9e5a RR	384	extern struct kernel_param_ops param_ops_string;
	385	extern int param_set_copystring(const char val, const struct kernel_param );
	386	extern int param_get_string(char buffer, const struct kernel_param kp);
1da177e4	387
1da177e4 LT	388	/* for exporting parameters in /sys/parameters */
	389
	390	struct module;
	391
ef665c1a	392	#if defined(CONFIG_SYSFS) && defined(CONFIG_MODULES)
1da177e4	393	extern int module_param_sysfs_setup(struct module *mod,
9bbb9e5a	394	const struct kernel_param *kparam,
1da177e4 LT	395	unsigned int num_params);
	396
	397	extern void module_param_sysfs_remove(struct module *mod);
ef665c1a RD	398	#else
ef665c1a RD	399	static inline int module_param_sysfs_setup(struct module *mod,
9bbb9e5a	400	const struct kernel_param *kparam,
ef665c1a RD	401	unsigned int num_params)
	402	{
	403	return 0;
	404	}
	405
	406	static inline void module_param_sysfs_remove(struct module *mod)
	407	{ }
	408	#endif
1da177e4 LT	409
1da177e4 LT	410	#endif /* _LINUX_MODULE_PARAMS_H */