[mirror_ubuntu-zesty-kernel.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)

/* One for each parameter, describing how to use it.  Some files do
   multiple of these per line, so can't just use MODULE_INFO. */
#define MODULE_PARM_DESC(_parm, desc) \
	__MODULE_INFO(parm, _parm, #_parm ":" desc)

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 elemsize;
	unsigned int *num;
	const struct kernel_param_ops *ops;
	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")

/**
 * parameq - checks if two parameter names match
 * @name1: parameter name 1
 * @name2: parameter name 2
 *
 * Returns true if the two parameter names are equal.
 * Dashes (-) are considered equal to underscores (_).
 */
extern bool parameq(const char *name1, const char *name2);

/**
 * parameqn - checks if two parameter names match
 * @name1: parameter name 1
 * @name2: parameter name 2
 * @n: the length to compare
 *
 * Similar to parameq(), except it compares @n characters.
 */
extern bool parameqn(const char *name1, const char *name2, size_t n);

/* 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)

/* An int, which can only be set like a bool (though it shows as an int). */
extern struct kernel_param_ops param_ops_bint;
extern int param_set_bint(const char *val, const struct kernel_param *kp);
#define param_get_bint param_get_int
#define param_check_bint param_check_int

/**
 * 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)		\
	param_check_##type(name, &(array)[0]);				\
	static const struct kparam_array __param_arr_##name		\
	= { .max = ARRAY_SIZE(array), .num = nump,                      \
	    .ops = &param_ops_##type,					\
	    .elemsize = sizeof(array[0]), .elem = 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
639938eb PG	34	/* One for each parameter, describing how to use it. Some files do
	35	multiple of these per line, so can't just use MODULE_INFO. */
	36	#define MODULE_PARM_DESC(_parm, desc) \
	37	__MODULE_INFO(parm, _parm, #_parm ":" desc)
	38
1da177e4 LT	39	struct kernel_param;
1da177e4 LT	40
9bbb9e5a RR	41	struct kernel_param_ops {
	42	/* Returns 0, or -errno. arg is in kp->arg. */
	43	int (set)(const char val, const struct kernel_param *kp);
	44	/* Returns length written or -errno. Buffer is 4k (ie. be short!) */
	45	int (get)(char buffer, const struct kernel_param *kp);
e6df34a4 RR	46	/* Optional function to free kp->arg when module unloaded. */
e6df34a4 RR	47	void (free)(void arg);
9bbb9e5a	48	};
1da177e4	49
45fcc70c	50	/* Flag bits for kernel_param.flags */
fddd5201	51	#define KPARAM_ISBOOL 2
45fcc70c	52
1da177e4 LT	53	struct kernel_param {
1da177e4 LT	54	const char *name;
9bbb9e5a	55	const struct kernel_param_ops *ops;
45fcc70c RR	56	u16 perm;
45fcc70c RR	57	u16 flags;
22e48eaf JB	58	union {
	59	void *arg;
	60	const struct kparam_string *str;
	61	const struct kparam_array *arr;
	62	};
1da177e4 LT	63	};
	64
	65	/* Special one for strings we want to copy into */
	66	struct kparam_string {
	67	unsigned int maxlen;
	68	char *string;
	69	};
	70
	71	/* Special one for arrays */
	72	struct kparam_array
	73	{
	74	unsigned int max;
c5be0b2e	75	unsigned int elemsize;
1da177e4	76	unsigned int *num;
9bbb9e5a	77	const struct kernel_param_ops *ops;
1da177e4 LT	78	void *elem;
	79	};
	80
546970bc RR	81	/**
	82	* module_param - typesafe helper for a module/cmdline parameter
	83	* @value: the variable to alter, and exposed parameter name.
	84	* @type: the type of the parameter
	85	* @perm: visibility in sysfs.
	86	*
	87	* @value becomes the module parameter, or (prefixed by KBUILD_MODNAME and a
	88	* ".") the kernel commandline parameter. Note that - is changed to _, so
	89	* the user can use "foo-bar=1" even for variable "foo_bar".
	90	*
	91	* @perm is 0 if the the variable is not to appear in sysfs, or 0444
	92	* for world-readable, 0644 for root-writable, etc. Note that if it
	93	* is writable, you may need to use kparam_block_sysfs_write() around
	94	* accesses (esp. charp, which can be kfreed when it changes).
	95	*
	96	* The @type is simply pasted to refer to a param_ops_##type and a
	97	* param_check_##type: for convenience many standard types are provided but
	98	* you can create your own by defining those variables.
	99	*
	100	* Standard types are:
	101	* byte, short, ushort, int, uint, long, ulong
	102	* charp: a character pointer
	103	* bool: a bool, values 0/1, y/n, Y/N.
	104	* invbool: the above, only sense-reversed (N = true).
	105	*/
	106	#define module_param(name, type, perm) \
	107	module_param_named(name, name, type, perm)
	108
	109	/**
	110	* module_param_named - typesafe helper for a renamed module/cmdline parameter
	111	* @name: a valid C identifier which is the parameter name.
	112	* @value: the actual lvalue to alter.
	113	* @type: the type of the parameter
	114	* @perm: visibility in sysfs.
	115	*
	116	* Usually it's a good idea to have variable names and user-exposed names the
	117	* same, but that's harder if the variable must be non-static or is inside a
	118	* structure. This allows exposure under a different name.
	119	*/
	120	#define module_param_named(name, value, type, perm) \
	121	param_check_##type(name, &(value)); \
	122	module_param_cb(name, &param_ops_##type, &value, perm); \
	123	__MODULE_PARM_TYPE(name, #type)
	124
	125	/**
	126	* module_param_cb - general callback for a module/cmdline parameter
	127	* @name: a valid C identifier which is the parameter name.
	128	* @ops: the set & get operations for this parameter.
	129	* @perm: visibility in sysfs.
	130	*
	131	* The ops can have NULL set or get functions.
	132	*/
	133	#define module_param_cb(name, ops, arg, perm) \
	134	__module_param_call(MODULE_PARAM_PREFIX, \
a6de51b2	135	name, ops, arg, __same_type((arg), bool *), perm)
546970bc	136
91d35dd9 IK	137	/* On alpha, ia64 and ppc64 relocations to global data cannot go into
	138	read-only sections (which is part of respective UNIX ABI on these
	139	platforms). So 'const' makes no sense and even causes compile failures
	140	with some compilers. */
	141	#if defined(CONFIG_ALPHA) \|\| defined(CONFIG_IA64) \|\| defined(CONFIG_PPC64)
	142	#define __moduleparam_const
	143	#else
	144	#define __moduleparam_const const
	145	#endif
	146
1da177e4	147	/* This is the fundamental function for registering boot/module
546970bc	148	parameters. */
9bbb9e5a	149	#define __module_param_call(prefix, name, ops, arg, isbool, perm) \
9774a1f5 AD	150	/* Default value instead of permissions? */ \
9774a1f5 AD	151	static int __param_perm_check_##name __attribute__((unused)) = \
730b69d2 RR	152	BUILD_BUG_ON_ZERO((perm) < 0 \|\| (perm) > 0777 \|\| ((perm) & 2)) \
730b69d2 RR	153	+ BUILD_BUG_ON_ZERO(sizeof(""prefix) > MAX_PARAM_PREFIX_LEN); \
22e48eaf	154	static const char __param_str_##name[] = prefix #name; \
91d35dd9	155	static struct kernel_param __moduleparam_const __param_##name \
3ff6eecc	156	__used \
1da177e4	157	__attribute__ ((unused,__section__ ("__param"),aligned(sizeof(void *)))) \
9bbb9e5a RR	158	= { __param_str_##name, ops, perm, isbool ? KPARAM_ISBOOL : 0, \
	159	{ arg } }
	160
	161	/* Obsolete - use module_param_cb() */
	162	#define module_param_call(name, set, get, arg, perm) \
	163	static struct kernel_param_ops __param_ops_##name = \
	164	{ (void )set, (void )get }; \
	165	__module_param_call(MODULE_PARAM_PREFIX, \
	166	name, &__param_ops_##name, arg, \
a6de51b2	167	__same_type(arg, bool *), \
9bbb9e5a RR	168	(perm) + sizeof(__check_old_set_param(set))*0)
	169
	170	/* We don't get oldget: it's often a new-style param_get_uint, etc. */
	171	static inline int
	172	__check_old_set_param(int (oldset)(const char , struct kernel_param *))
	173	{
	174	return 0;
	175	}
1da177e4	176
907b29eb RR	177	/**
	178	* kparam_block_sysfs_write - make sure a parameter isn't written via sysfs.
	179	* @name: the name of the parameter
	180	*
	181	* There's no point blocking write on a paramter that isn't writable via sysfs!
	182	*/
	183	#define kparam_block_sysfs_write(name) \
	184	do { \
	185	BUG_ON(!(__param_##name.perm & 0222)); \
	186	__kernel_param_lock(); \
	187	} while (0)
	188
	189	/**
	190	* kparam_unblock_sysfs_write - allows sysfs to write to a parameter again.
	191	* @name: the name of the parameter
	192	*/
	193	#define kparam_unblock_sysfs_write(name) \
	194	do { \
	195	BUG_ON(!(__param_##name.perm & 0222)); \
	196	__kernel_param_unlock(); \
	197	} while (0)
	198
	199	/**
	200	* kparam_block_sysfs_read - make sure a parameter isn't read via sysfs.
	201	* @name: the name of the parameter
	202	*
	203	* This also blocks sysfs writes.
	204	*/
	205	#define kparam_block_sysfs_read(name) \
	206	do { \
	207	BUG_ON(!(__param_##name.perm & 0444)); \
	208	__kernel_param_lock(); \
	209	} while (0)
	210
	211	/**
	212	* kparam_unblock_sysfs_read - allows sysfs to read a parameter again.
	213	* @name: the name of the parameter
	214	*/
	215	#define kparam_unblock_sysfs_read(name) \
	216	do { \
	217	BUG_ON(!(__param_##name.perm & 0444)); \
	218	__kernel_param_unlock(); \
	219	} while (0)
	220
	221	#ifdef CONFIG_SYSFS
	222	extern void __kernel_param_lock(void);
	223	extern void __kernel_param_unlock(void);
	224	#else
	225	static inline void __kernel_param_lock(void)
	226	{
	227	}
	228	static inline void __kernel_param_unlock(void)
	229	{
	230	}
	231	#endif
	232
67e67cea RR	233	#ifndef MODULE
	234	/**
	235	* core_param - define a historical core kernel parameter.
	236	* @name: the name of the cmdline and sysfs parameter (often the same as var)
	237	* @var: the variable
546970bc	238	* @type: the type of the parameter
67e67cea RR	239	* @perm: visibility in sysfs
	240	*
	241	* core_param is just like module_param(), but cannot be modular and
	242	* doesn't add a prefix (such as "printk."). This is for compatibility
	243	* with __setup(), and it makes sense as truly core parameters aren't
	244	* tied to the particular file they're in.
	245	*/
	246	#define core_param(name, var, type, perm) \
	247	param_check_##type(name, &(var)); \
9bbb9e5a	248	__module_param_call("", name, &param_ops_##type, \
fddd5201	249	&var, __same_type(var, bool), perm)
67e67cea RR	250	#endif /* !MODULE */
67e67cea RR	251
546970bc RR	252	/**
	253	* module_param_string - a char array parameter
	254	* @name: the name of the parameter
	255	* @string: the string variable
	256	* @len: the maximum length of the string, incl. terminator
	257	* @perm: visibility in sysfs.
	258	*
	259	* This actually copies the string when it's set (unlike type charp).
	260	* @len is usually just sizeof(string).
	261	*/
1da177e4	262	#define module_param_string(name, string, len, perm) \
22e48eaf	263	static const struct kparam_string __param_string_##name \
1da177e4	264	= { len, string }; \
fddd5201	265	__module_param_call(MODULE_PARAM_PREFIX, name, \
9bbb9e5a	266	&param_ops_string, \
fddd5201	267	.str = &__param_string_##name, 0, perm); \
1da177e4 LT	268	__MODULE_PARM_TYPE(name, "string")
1da177e4 LT	269
b1e4d20c MS	270	/**
	271	* parameq - checks if two parameter names match
	272	* @name1: parameter name 1
	273	* @name2: parameter name 2
	274	*
	275	* Returns true if the two parameter names are equal.
	276	* Dashes (-) are considered equal to underscores (_).
	277	*/
	278	extern bool parameq(const char name1, const char name2);
	279
	280	/**
	281	* parameqn - checks if two parameter names match
	282	* @name1: parameter name 1
	283	* @name2: parameter name 2
	284	* @n: the length to compare
	285	*
	286	* Similar to parameq(), except it compares @n characters.
	287	*/
	288	extern bool parameqn(const char name1, const char name2, size_t n);
	289
1da177e4 LT	290	/* Called on module insert or kernel boot */
	291	extern int parse_args(const char *name,
	292	char *args,
914dcaa8	293	const struct kernel_param *params,
1da177e4 LT	294	unsigned num,
	295	int (unknown)(char param, char *val));
	296
e180a6b7 RR	297	/* Called by module remove. */
	298	#ifdef CONFIG_SYSFS
	299	extern void destroy_params(const struct kernel_param *params, unsigned num);
	300	#else
	301	static inline void destroy_params(const struct kernel_param *params,
	302	unsigned num)
	303	{
	304	}
	305	#endif /* !CONFIG_SYSFS */
	306
1da177e4 LT	307	/* All the helper functions */
	308	/* The macros to do compile-time type checking stolen from Jakub
	309	Jelinek, who IIRC came up with this idea for the 2.4 module init code. */
	310	#define __param_check(name, p, type) \
	311	static inline type *__check_##name(void) { return(p); }
	312
9bbb9e5a RR	313	extern struct kernel_param_ops param_ops_byte;
	314	extern int param_set_byte(const char val, const struct kernel_param kp);
	315	extern int param_get_byte(char buffer, const struct kernel_param kp);
1da177e4 LT	316	#define param_check_byte(name, p) __param_check(name, p, unsigned char)
1da177e4 LT	317
9bbb9e5a RR	318	extern struct kernel_param_ops param_ops_short;
	319	extern int param_set_short(const char val, const struct kernel_param kp);
	320	extern int param_get_short(char buffer, const struct kernel_param kp);
1da177e4 LT	321	#define param_check_short(name, p) __param_check(name, p, short)
1da177e4 LT	322
9bbb9e5a RR	323	extern struct kernel_param_ops param_ops_ushort;
	324	extern int param_set_ushort(const char val, const struct kernel_param kp);
	325	extern int param_get_ushort(char buffer, const struct kernel_param kp);
1da177e4 LT	326	#define param_check_ushort(name, p) __param_check(name, p, unsigned short)
1da177e4 LT	327
9bbb9e5a RR	328	extern struct kernel_param_ops param_ops_int;
	329	extern int param_set_int(const char val, const struct kernel_param kp);
	330	extern int param_get_int(char buffer, const struct kernel_param kp);
1da177e4 LT	331	#define param_check_int(name, p) __param_check(name, p, int)
1da177e4 LT	332
9bbb9e5a RR	333	extern struct kernel_param_ops param_ops_uint;
	334	extern int param_set_uint(const char val, const struct kernel_param kp);
	335	extern int param_get_uint(char buffer, const struct kernel_param kp);
1da177e4 LT	336	#define param_check_uint(name, p) __param_check(name, p, unsigned int)
1da177e4 LT	337
9bbb9e5a RR	338	extern struct kernel_param_ops param_ops_long;
	339	extern int param_set_long(const char val, const struct kernel_param kp);
	340	extern int param_get_long(char buffer, const struct kernel_param kp);
1da177e4 LT	341	#define param_check_long(name, p) __param_check(name, p, long)
1da177e4 LT	342
9bbb9e5a RR	343	extern struct kernel_param_ops param_ops_ulong;
	344	extern int param_set_ulong(const char val, const struct kernel_param kp);
	345	extern int param_get_ulong(char buffer, const struct kernel_param kp);
1da177e4 LT	346	#define param_check_ulong(name, p) __param_check(name, p, unsigned long)
1da177e4 LT	347
9bbb9e5a RR	348	extern struct kernel_param_ops param_ops_charp;
	349	extern int param_set_charp(const char val, const struct kernel_param kp);
	350	extern int param_get_charp(char buffer, const struct kernel_param kp);
1da177e4 LT	351	#define param_check_charp(name, p) __param_check(name, p, char *)
1da177e4 LT	352
fddd5201	353	/* For historical reasons "bool" parameters can be (unsigned) "int". */
9bbb9e5a RR	354	extern struct kernel_param_ops param_ops_bool;
	355	extern int param_set_bool(const char val, const struct kernel_param kp);
	356	extern int param_get_bool(char buffer, const struct kernel_param kp);
fddd5201 RR	357	#define param_check_bool(name, p) \
	358	static inline void __check_##name(void) \
	359	{ \
a6de51b2 RR	360	BUILD_BUG_ON(!__same_type((p), bool *) && \
	361	!__same_type((p), unsigned int *) && \
	362	!__same_type((p), int *)); \
fddd5201	363	}
1da177e4	364
9bbb9e5a RR	365	extern struct kernel_param_ops param_ops_invbool;
	366	extern int param_set_invbool(const char val, const struct kernel_param kp);
	367	extern int param_get_invbool(char buffer, const struct kernel_param kp);
9a71af2c	368	#define param_check_invbool(name, p) __param_check(name, p, bool)
1da177e4	369
69116f27 RR	370	/* An int, which can only be set like a bool (though it shows as an int). */
	371	extern struct kernel_param_ops param_ops_bint;
	372	extern int param_set_bint(const char val, const struct kernel_param kp);
	373	#define param_get_bint param_get_int
	374	#define param_check_bint param_check_int
	375
546970bc RR	376	/**
	377	* module_param_array - a parameter which is an array of some type
	378	* @name: the name of the array variable
	379	* @type: the type, as per module_param()
	380	* @nump: optional pointer filled in with the number written
	381	* @perm: visibility in sysfs
	382	*
	383	* Input and output are as comma-separated values. Commas inside values
	384	* don't work properly (eg. an array of charp).
	385	*
	386	* ARRAY_SIZE(@name) is used to determine the number of elements in the
	387	* array, so the definition must be visible.
	388	*/
	389	#define module_param_array(name, type, nump, perm) \
	390	module_param_array_named(name, name, type, nump, perm)
	391
	392	/**
	393	* module_param_array_named - renamed parameter which is an array of some type
	394	* @name: a valid C identifier which is the parameter name
	395	* @array: the name of the array variable
	396	* @type: the type, as per module_param()
	397	* @nump: optional pointer filled in with the number written
	398	* @perm: visibility in sysfs
	399	*
	400	* This exposes a different name than the actual variable name. See
	401	* module_param_named() for why this might be necessary.
	402	*/
1da177e4	403	#define module_param_array_named(name, array, type, nump, perm) \
bafeafea	404	param_check_##type(name, &(array)[0]); \
22e48eaf	405	static const struct kparam_array __param_arr_##name \
c5be0b2e RK	406	= { .max = ARRAY_SIZE(array), .num = nump, \
	407	.ops = &param_ops_##type, \
	408	.elemsize = sizeof(array[0]), .elem = array }; \
fddd5201	409	__module_param_call(MODULE_PARAM_PREFIX, name, \
9bbb9e5a	410	&param_array_ops, \
fddd5201 RR	411	.arr = &__param_arr_##name, \
fddd5201 RR	412	__same_type(array[0], bool), perm); \
1da177e4 LT	413	__MODULE_PARM_TYPE(name, "array of " #type)
1da177e4 LT	414
9bbb9e5a	415	extern struct kernel_param_ops param_array_ops;
1da177e4	416
9bbb9e5a RR	417	extern struct kernel_param_ops param_ops_string;
	418	extern int param_set_copystring(const char val, const struct kernel_param );
	419	extern int param_get_string(char buffer, const struct kernel_param kp);
1da177e4	420
1da177e4 LT	421	/* for exporting parameters in /sys/parameters */
	422
	423	struct module;
	424
ef665c1a	425	#if defined(CONFIG_SYSFS) && defined(CONFIG_MODULES)
1da177e4	426	extern int module_param_sysfs_setup(struct module *mod,
9bbb9e5a	427	const struct kernel_param *kparam,
1da177e4 LT	428	unsigned int num_params);
	429
	430	extern void module_param_sysfs_remove(struct module *mod);
ef665c1a RD	431	#else
ef665c1a RD	432	static inline int module_param_sysfs_setup(struct module *mod,
9bbb9e5a	433	const struct kernel_param *kparam,
ef665c1a RD	434	unsigned int num_params)
	435	{
	436	return 0;
	437	}
	438
	439	static inline void module_param_sysfs_remove(struct module *mod)
	440	{ }
	441	#endif
1da177e4 LT	442
1da177e4 LT	443	#endif /* _LINUX_MODULE_PARAMS_H */