[linux.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))

#ifdef MODULE
#define __MODULE_INFO(tag, name, info)					  \
static const char __UNIQUE_ID(name)[]					  \
  __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 __UNIQUE_ID(name) {}
#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);
};

struct kernel_param {
	const char *name;
	const struct kernel_param_ops *ops;
	u16 perm;
	s16 level;
	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, perm, -1)

/**
 * <level>_param_cb - general callback for a module/cmdline parameter
 *                    to be evaluated before certain initcall level
 * @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 __level_param_cb(name, ops, arg, perm, level)			\
	__module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, level)

#define core_param_cb(name, ops, arg, perm)		\
	__level_param_cb(name, ops, arg, perm, 1)

#define postcore_param_cb(name, ops, arg, perm)		\
	__level_param_cb(name, ops, arg, perm, 2)

#define arch_param_cb(name, ops, arg, perm)		\
	__level_param_cb(name, ops, arg, perm, 3)

#define subsys_param_cb(name, ops, arg, perm)		\
	__level_param_cb(name, ops, arg, perm, 4)

#define fs_param_cb(name, ops, arg, perm)		\
	__level_param_cb(name, ops, arg, perm, 5)

#define device_param_cb(name, ops, arg, perm)		\
	__level_param_cb(name, ops, arg, perm, 6)

#define late_param_cb(name, ops, arg, perm)		\
	__level_param_cb(name, ops, arg, perm, 7)

/* 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, perm, level)	\
	/* 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, level, { 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,		\
			    (perm) + sizeof(__check_old_set_param(set))*0, -1)

/* 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, perm, -1)
#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, perm, -1);	\
	__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,
		      s16 level_min,
		      s16 level_max,
		      int (*unknown)(char *param, char *val,
			      const char *doing));

/* 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 *)

/* We used to allow int as well as bool.  We're taking that away! */
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) __param_check(name, p, bool)

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,			\
			    perm, -1);					\
	__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/module/.../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
b75be420	19	#ifdef MODULE
1da177e4	20	#define __MODULE_INFO(tag, name, info) \
34182eea	21	static const char __UNIQUE_ID(name)[] \
b6472776 JB	22	__used __attribute__((section(".modinfo"), unused, aligned(1))) \
b6472776 JB	23	= __stringify(tag) "=" info
1da177e4	24	#else /* !MODULE */
b75be420 LW	25	/* This struct is here for syntactic coherency, it is not used */
b75be420 LW	26	#define __MODULE_INFO(tag, name, info) \
34182eea	27	struct __UNIQUE_ID(name) {}
1da177e4 LT	28	#endif
	29	#define __MODULE_PARM_TYPE(name, _type) \
	30	__MODULE_INFO(parmtype, name##type, #name ":" _type)
	31
639938eb PG	32	/* One for each parameter, describing how to use it. Some files do
	33	multiple of these per line, so can't just use MODULE_INFO. */
	34	#define MODULE_PARM_DESC(_parm, desc) \
	35	__MODULE_INFO(parm, _parm, #_parm ":" desc)
	36
1da177e4 LT	37	struct kernel_param;
1da177e4 LT	38
9bbb9e5a RR	39	struct kernel_param_ops {
	40	/* Returns 0, or -errno. arg is in kp->arg. */
	41	int (set)(const char val, const struct kernel_param *kp);
	42	/* Returns length written or -errno. Buffer is 4k (ie. be short!) */
	43	int (get)(char buffer, const struct kernel_param *kp);
e6df34a4 RR	44	/* Optional function to free kp->arg when module unloaded. */
e6df34a4 RR	45	void (free)(void arg);
9bbb9e5a	46	};
1da177e4 LT	47
	48	struct kernel_param {
	49	const char *name;
9bbb9e5a	50	const struct kernel_param_ops *ops;
45fcc70c	51	u16 perm;
026cee00	52	s16 level;
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;
c5be0b2e	70	unsigned int elemsize;
1da177e4	71	unsigned int *num;
9bbb9e5a	72	const struct kernel_param_ops *ops;
1da177e4 LT	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) \
ae82fdb1	129	__module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, -1)
026cee00 PM	130
	131	/**
	132	* <level>_param_cb - general callback for a module/cmdline parameter
	133	* to be evaluated before certain initcall level
	134	* @name: a valid C identifier which is the parameter name.
	135	* @ops: the set & get operations for this parameter.
	136	* @perm: visibility in sysfs.
	137	*
	138	* The ops can have NULL set or get functions.
	139	*/
	140	#define __level_param_cb(name, ops, arg, perm, level) \
	141	__module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, level)
	142
	143	#define core_param_cb(name, ops, arg, perm) \
	144	__level_param_cb(name, ops, arg, perm, 1)
	145
	146	#define postcore_param_cb(name, ops, arg, perm) \
	147	__level_param_cb(name, ops, arg, perm, 2)
	148
	149	#define arch_param_cb(name, ops, arg, perm) \
	150	__level_param_cb(name, ops, arg, perm, 3)
	151
	152	#define subsys_param_cb(name, ops, arg, perm) \
	153	__level_param_cb(name, ops, arg, perm, 4)
	154
	155	#define fs_param_cb(name, ops, arg, perm) \
	156	__level_param_cb(name, ops, arg, perm, 5)
	157
	158	#define device_param_cb(name, ops, arg, perm) \
	159	__level_param_cb(name, ops, arg, perm, 6)
	160
	161	#define late_param_cb(name, ops, arg, perm) \
	162	__level_param_cb(name, ops, arg, perm, 7)
546970bc	163
91d35dd9 IK	164	/* On alpha, ia64 and ppc64 relocations to global data cannot go into
	165	read-only sections (which is part of respective UNIX ABI on these
	166	platforms). So 'const' makes no sense and even causes compile failures
	167	with some compilers. */
	168	#if defined(CONFIG_ALPHA) \|\| defined(CONFIG_IA64) \|\| defined(CONFIG_PPC64)
	169	#define __moduleparam_const
	170	#else
	171	#define __moduleparam_const const
	172	#endif
	173
1da177e4	174	/* This is the fundamental function for registering boot/module
546970bc	175	parameters. */
026cee00	176	#define __module_param_call(prefix, name, ops, arg, perm, level) \
9774a1f5 AD	177	/* Default value instead of permissions? */ \
9774a1f5 AD	178	static int __param_perm_check_##name __attribute__((unused)) = \
730b69d2 RR	179	BUILD_BUG_ON_ZERO((perm) < 0 \|\| (perm) > 0777 \|\| ((perm) & 2)) \
730b69d2 RR	180	+ BUILD_BUG_ON_ZERO(sizeof(""prefix) > MAX_PARAM_PREFIX_LEN); \
22e48eaf	181	static const char __param_str_##name[] = prefix #name; \
91d35dd9	182	static struct kernel_param __moduleparam_const __param_##name \
3ff6eecc	183	__used \
1da177e4	184	__attribute__ ((unused,__section__ ("__param"),aligned(sizeof(void *)))) \
026cee00	185	= { __param_str_##name, ops, perm, level, { arg } }
9bbb9e5a RR	186
	187	/* Obsolete - use module_param_cb() */
	188	#define module_param_call(name, set, get, arg, perm) \
	189	static struct kernel_param_ops __param_ops_##name = \
	190	{ (void )set, (void )get }; \
	191	__module_param_call(MODULE_PARAM_PREFIX, \
	192	name, &__param_ops_##name, arg, \
ae82fdb1	193	(perm) + sizeof(__check_old_set_param(set))*0, -1)
9bbb9e5a RR	194
	195	/* We don't get oldget: it's often a new-style param_get_uint, etc. */
	196	static inline int
	197	__check_old_set_param(int (oldset)(const char , struct kernel_param *))
	198	{
	199	return 0;
	200	}
1da177e4	201
907b29eb RR	202	/**
	203	* kparam_block_sysfs_write - make sure a parameter isn't written via sysfs.
	204	* @name: the name of the parameter
	205	*
	206	* There's no point blocking write on a paramter that isn't writable via sysfs!
	207	*/
	208	#define kparam_block_sysfs_write(name) \
	209	do { \
	210	BUG_ON(!(__param_##name.perm & 0222)); \
	211	__kernel_param_lock(); \
	212	} while (0)
	213
	214	/**
	215	* kparam_unblock_sysfs_write - allows sysfs to write to a parameter again.
	216	* @name: the name of the parameter
	217	*/
	218	#define kparam_unblock_sysfs_write(name) \
	219	do { \
	220	BUG_ON(!(__param_##name.perm & 0222)); \
	221	__kernel_param_unlock(); \
	222	} while (0)
	223
	224	/**
	225	* kparam_block_sysfs_read - make sure a parameter isn't read via sysfs.
	226	* @name: the name of the parameter
	227	*
	228	* This also blocks sysfs writes.
	229	*/
	230	#define kparam_block_sysfs_read(name) \
	231	do { \
	232	BUG_ON(!(__param_##name.perm & 0444)); \
	233	__kernel_param_lock(); \
	234	} while (0)
	235
	236	/**
	237	* kparam_unblock_sysfs_read - allows sysfs to read a parameter again.
	238	* @name: the name of the parameter
	239	*/
	240	#define kparam_unblock_sysfs_read(name) \
	241	do { \
	242	BUG_ON(!(__param_##name.perm & 0444)); \
	243	__kernel_param_unlock(); \
	244	} while (0)
	245
	246	#ifdef CONFIG_SYSFS
	247	extern void __kernel_param_lock(void);
	248	extern void __kernel_param_unlock(void);
	249	#else
	250	static inline void __kernel_param_lock(void)
	251	{
	252	}
	253	static inline void __kernel_param_unlock(void)
	254	{
	255	}
	256	#endif
	257
67e67cea RR	258	#ifndef MODULE
	259	/**
	260	* core_param - define a historical core kernel parameter.
	261	* @name: the name of the cmdline and sysfs parameter (often the same as var)
	262	* @var: the variable
546970bc	263	* @type: the type of the parameter
67e67cea RR	264	* @perm: visibility in sysfs
	265	*
	266	* core_param is just like module_param(), but cannot be modular and
	267	* doesn't add a prefix (such as "printk."). This is for compatibility
	268	* with __setup(), and it makes sense as truly core parameters aren't
	269	* tied to the particular file they're in.
	270	*/
	271	#define core_param(name, var, type, perm) \
	272	param_check_##type(name, &(var)); \
ae82fdb1	273	__module_param_call("", name, &param_ops_##type, &var, perm, -1)
67e67cea RR	274	#endif /* !MODULE */
67e67cea RR	275
546970bc RR	276	/**
	277	* module_param_string - a char array parameter
	278	* @name: the name of the parameter
	279	* @string: the string variable
	280	* @len: the maximum length of the string, incl. terminator
	281	* @perm: visibility in sysfs.
	282	*
	283	* This actually copies the string when it's set (unlike type charp).
	284	* @len is usually just sizeof(string).
	285	*/
1da177e4	286	#define module_param_string(name, string, len, perm) \
22e48eaf	287	static const struct kparam_string __param_string_##name \
1da177e4	288	= { len, string }; \
fddd5201	289	__module_param_call(MODULE_PARAM_PREFIX, name, \
9bbb9e5a	290	&param_ops_string, \
ae82fdb1	291	.str = &__param_string_##name, perm, -1); \
1da177e4 LT	292	__MODULE_PARM_TYPE(name, "string")
1da177e4 LT	293
b1e4d20c MS	294	/**
	295	* parameq - checks if two parameter names match
	296	* @name1: parameter name 1
	297	* @name2: parameter name 2
	298	*
	299	* Returns true if the two parameter names are equal.
	300	* Dashes (-) are considered equal to underscores (_).
	301	*/
	302	extern bool parameq(const char name1, const char name2);
	303
	304	/**
	305	* parameqn - checks if two parameter names match
	306	* @name1: parameter name 1
	307	* @name2: parameter name 2
	308	* @n: the length to compare
	309	*
	310	* Similar to parameq(), except it compares @n characters.
	311	*/
	312	extern bool parameqn(const char name1, const char name2, size_t n);
	313
1da177e4 LT	314	/* Called on module insert or kernel boot */
	315	extern int parse_args(const char *name,
	316	char *args,
914dcaa8	317	const struct kernel_param *params,
1da177e4	318	unsigned num,
026cee00 PM	319	s16 level_min,
026cee00 PM	320	s16 level_max,
9fb48c74 JC	321	int (unknown)(char param, char *val,
9fb48c74 JC	322	const char *doing));
1da177e4	323
e180a6b7 RR	324	/* Called by module remove. */
	325	#ifdef CONFIG_SYSFS
	326	extern void destroy_params(const struct kernel_param *params, unsigned num);
	327	#else
	328	static inline void destroy_params(const struct kernel_param *params,
	329	unsigned num)
	330	{
	331	}
	332	#endif /* !CONFIG_SYSFS */
	333
1da177e4 LT	334	/* All the helper functions */
	335	/* The macros to do compile-time type checking stolen from Jakub
	336	Jelinek, who IIRC came up with this idea for the 2.4 module init code. */
	337	#define __param_check(name, p, type) \
	338	static inline type *__check_##name(void) { return(p); }
	339
9bbb9e5a RR	340	extern struct kernel_param_ops param_ops_byte;
	341	extern int param_set_byte(const char val, const struct kernel_param kp);
	342	extern int param_get_byte(char buffer, const struct kernel_param kp);
1da177e4 LT	343	#define param_check_byte(name, p) __param_check(name, p, unsigned char)
1da177e4 LT	344
9bbb9e5a RR	345	extern struct kernel_param_ops param_ops_short;
	346	extern int param_set_short(const char val, const struct kernel_param kp);
	347	extern int param_get_short(char buffer, const struct kernel_param kp);
1da177e4 LT	348	#define param_check_short(name, p) __param_check(name, p, short)
1da177e4 LT	349
9bbb9e5a RR	350	extern struct kernel_param_ops param_ops_ushort;
	351	extern int param_set_ushort(const char val, const struct kernel_param kp);
	352	extern int param_get_ushort(char buffer, const struct kernel_param kp);
1da177e4 LT	353	#define param_check_ushort(name, p) __param_check(name, p, unsigned short)
1da177e4 LT	354
9bbb9e5a RR	355	extern struct kernel_param_ops param_ops_int;
	356	extern int param_set_int(const char val, const struct kernel_param kp);
	357	extern int param_get_int(char buffer, const struct kernel_param kp);
1da177e4 LT	358	#define param_check_int(name, p) __param_check(name, p, int)
1da177e4 LT	359
9bbb9e5a RR	360	extern struct kernel_param_ops param_ops_uint;
	361	extern int param_set_uint(const char val, const struct kernel_param kp);
	362	extern int param_get_uint(char buffer, const struct kernel_param kp);
1da177e4 LT	363	#define param_check_uint(name, p) __param_check(name, p, unsigned int)
1da177e4 LT	364
9bbb9e5a RR	365	extern struct kernel_param_ops param_ops_long;
	366	extern int param_set_long(const char val, const struct kernel_param kp);
	367	extern int param_get_long(char buffer, const struct kernel_param kp);
1da177e4 LT	368	#define param_check_long(name, p) __param_check(name, p, long)
1da177e4 LT	369
9bbb9e5a RR	370	extern struct kernel_param_ops param_ops_ulong;
	371	extern int param_set_ulong(const char val, const struct kernel_param kp);
	372	extern int param_get_ulong(char buffer, const struct kernel_param kp);
1da177e4 LT	373	#define param_check_ulong(name, p) __param_check(name, p, unsigned long)
1da177e4 LT	374
9bbb9e5a RR	375	extern struct kernel_param_ops param_ops_charp;
	376	extern int param_set_charp(const char val, const struct kernel_param kp);
	377	extern int param_get_charp(char buffer, const struct kernel_param kp);
1da177e4 LT	378	#define param_check_charp(name, p) __param_check(name, p, char *)
1da177e4 LT	379
72db395f	380	/* We used to allow int as well as bool. We're taking that away! */
9bbb9e5a RR	381	extern struct kernel_param_ops param_ops_bool;
	382	extern int param_set_bool(const char val, const struct kernel_param kp);
	383	extern int param_get_bool(char buffer, const struct kernel_param kp);
72db395f	384	#define param_check_bool(name, p) __param_check(name, p, bool)
1da177e4	385
9bbb9e5a RR	386	extern struct kernel_param_ops param_ops_invbool;
	387	extern int param_set_invbool(const char val, const struct kernel_param kp);
	388	extern int param_get_invbool(char buffer, const struct kernel_param kp);
9a71af2c	389	#define param_check_invbool(name, p) __param_check(name, p, bool)
1da177e4	390
69116f27 RR	391	/* An int, which can only be set like a bool (though it shows as an int). */
	392	extern struct kernel_param_ops param_ops_bint;
	393	extern int param_set_bint(const char val, const struct kernel_param kp);
	394	#define param_get_bint param_get_int
	395	#define param_check_bint param_check_int
	396
546970bc RR	397	/**
	398	* module_param_array - a parameter which is an array of some type
	399	* @name: the name of the array variable
	400	* @type: the type, as per module_param()
	401	* @nump: optional pointer filled in with the number written
	402	* @perm: visibility in sysfs
	403	*
	404	* Input and output are as comma-separated values. Commas inside values
	405	* don't work properly (eg. an array of charp).
	406	*
	407	* ARRAY_SIZE(@name) is used to determine the number of elements in the
	408	* array, so the definition must be visible.
	409	*/
	410	#define module_param_array(name, type, nump, perm) \
	411	module_param_array_named(name, name, type, nump, perm)
	412
	413	/**
	414	* module_param_array_named - renamed parameter which is an array of some type
	415	* @name: a valid C identifier which is the parameter name
	416	* @array: the name of the array variable
	417	* @type: the type, as per module_param()
	418	* @nump: optional pointer filled in with the number written
	419	* @perm: visibility in sysfs
	420	*
	421	* This exposes a different name than the actual variable name. See
	422	* module_param_named() for why this might be necessary.
	423	*/
1da177e4	424	#define module_param_array_named(name, array, type, nump, perm) \
bafeafea	425	param_check_##type(name, &(array)[0]); \
22e48eaf	426	static const struct kparam_array __param_arr_##name \
c5be0b2e RK	427	= { .max = ARRAY_SIZE(array), .num = nump, \
	428	.ops = &param_ops_##type, \
	429	.elemsize = sizeof(array[0]), .elem = array }; \
fddd5201	430	__module_param_call(MODULE_PARAM_PREFIX, name, \
9bbb9e5a	431	&param_array_ops, \
fddd5201	432	.arr = &__param_arr_##name, \
ae82fdb1	433	perm, -1); \
1da177e4 LT	434	__MODULE_PARM_TYPE(name, "array of " #type)
1da177e4 LT	435
9bbb9e5a	436	extern struct kernel_param_ops param_array_ops;
1da177e4	437
9bbb9e5a RR	438	extern struct kernel_param_ops param_ops_string;
	439	extern int param_set_copystring(const char val, const struct kernel_param );
	440	extern int param_get_string(char buffer, const struct kernel_param kp);
1da177e4	441
b634d130	442	/* for exporting parameters in /sys/module/.../parameters */
1da177e4 LT	443
	444	struct module;
	445
ef665c1a	446	#if defined(CONFIG_SYSFS) && defined(CONFIG_MODULES)
1da177e4	447	extern int module_param_sysfs_setup(struct module *mod,
9bbb9e5a	448	const struct kernel_param *kparam,
1da177e4 LT	449	unsigned int num_params);
	450
	451	extern void module_param_sysfs_remove(struct module *mod);
ef665c1a RD	452	#else
ef665c1a RD	453	static inline int module_param_sysfs_setup(struct module *mod,
9bbb9e5a	454	const struct kernel_param *kparam,
ef665c1a RD	455	unsigned int num_params)
	456	{
	457	return 0;
	458	}
	459
	460	static inline void module_param_sysfs_remove(struct module *mod)
	461	{ }
	462	#endif
1da177e4 LT	463
1da177e4 LT	464	#endif /* _LINUX_MODULE_PARAMS_H */