xref: /linux/include/linux/moduleparam.h (revision fd7d598270724cc787982ea48bbe17ad383a8b7f)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_MODULE_PARAMS_H
3 #define _LINUX_MODULE_PARAMS_H
4 /* (C) Copyright 2001, 2002 Rusty Russell IBM Corporation */
5 #include <linux/init.h>
6 #include <linux/stringify.h>
7 #include <linux/kernel.h>
8 
9 /* You can override this manually, but generally this should match the
10    module name. */
11 #ifdef MODULE
12 #define MODULE_PARAM_PREFIX /* empty */
13 #define __MODULE_INFO_PREFIX /* empty */
14 #else
15 #define MODULE_PARAM_PREFIX KBUILD_MODNAME "."
16 /* We cannot use MODULE_PARAM_PREFIX because some modules override it. */
17 #define __MODULE_INFO_PREFIX KBUILD_MODNAME "."
18 #endif
19 
20 /* Chosen so that structs with an unsigned long line up. */
21 #define MAX_PARAM_PREFIX_LEN (64 - sizeof(unsigned long))
22 
23 #define __MODULE_INFO(tag, name, info)					  \
24 	static const char __UNIQUE_ID(name)[]				  \
25 		__used __section(".modinfo") __aligned(1)		  \
26 		= __MODULE_INFO_PREFIX __stringify(tag) "=" info
27 
28 #define __MODULE_PARM_TYPE(name, _type)					  \
29 	__MODULE_INFO(parmtype, name##type, #name ":" _type)
30 
31 /* One for each parameter, describing how to use it.  Some files do
32    multiple of these per line, so can't just use MODULE_INFO. */
33 #define MODULE_PARM_DESC(_parm, desc) \
34 	__MODULE_INFO(parm, _parm, #_parm ":" desc)
35 
36 struct kernel_param;
37 
38 /*
39  * Flags available for kernel_param_ops
40  *
41  * NOARG - the parameter allows for no argument (foo instead of foo=1)
42  */
43 enum {
44 	KERNEL_PARAM_OPS_FL_NOARG = (1 << 0)
45 };
46 
47 struct kernel_param_ops {
48 	/* How the ops should behave */
49 	unsigned int flags;
50 	/* Returns 0, or -errno.  arg is in kp->arg. */
51 	int (*set)(const char *val, const struct kernel_param *kp);
52 	/* Returns length written or -errno.  Buffer is 4k (ie. be short!) */
53 	int (*get)(char *buffer, const struct kernel_param *kp);
54 	/* Optional function to free kp->arg when module unloaded. */
55 	void (*free)(void *arg);
56 };
57 
58 /*
59  * Flags available for kernel_param
60  *
61  * UNSAFE - the parameter is dangerous and setting it will taint the kernel
62  * HWPARAM - Hardware param not permitted in lockdown mode
63  */
64 enum {
65 	KERNEL_PARAM_FL_UNSAFE	= (1 << 0),
66 	KERNEL_PARAM_FL_HWPARAM	= (1 << 1),
67 };
68 
69 struct kernel_param {
70 	const char *name;
71 	struct module *mod;
72 	const struct kernel_param_ops *ops;
73 	const u16 perm;
74 	s8 level;
75 	u8 flags;
76 	union {
77 		void *arg;
78 		const struct kparam_string *str;
79 		const struct kparam_array *arr;
80 	};
81 };
82 
83 extern const struct kernel_param __start___param[], __stop___param[];
84 
85 /* Special one for strings we want to copy into */
86 struct kparam_string {
87 	unsigned int maxlen;
88 	char *string;
89 };
90 
91 /* Special one for arrays */
92 struct kparam_array
93 {
94 	unsigned int max;
95 	unsigned int elemsize;
96 	unsigned int *num;
97 	const struct kernel_param_ops *ops;
98 	void *elem;
99 };
100 
101 /**
102  * module_param - typesafe helper for a module/cmdline parameter
103  * @name: the variable to alter, and exposed parameter name.
104  * @type: the type of the parameter
105  * @perm: visibility in sysfs.
106  *
107  * @name becomes the module parameter, or (prefixed by KBUILD_MODNAME and a
108  * ".") the kernel commandline parameter.  Note that - is changed to _, so
109  * the user can use "foo-bar=1" even for variable "foo_bar".
110  *
111  * @perm is 0 if the variable is not to appear in sysfs, or 0444
112  * for world-readable, 0644 for root-writable, etc.  Note that if it
113  * is writable, you may need to use kernel_param_lock() around
114  * accesses (esp. charp, which can be kfreed when it changes).
115  *
116  * The @type is simply pasted to refer to a param_ops_##type and a
117  * param_check_##type: for convenience many standard types are provided but
118  * you can create your own by defining those variables.
119  *
120  * Standard types are:
121  *	byte, hexint, short, ushort, int, uint, long, ulong
122  *	charp: a character pointer
123  *	bool: a bool, values 0/1, y/n, Y/N.
124  *	invbool: the above, only sense-reversed (N = true).
125  */
126 #define module_param(name, type, perm)				\
127 	module_param_named(name, name, type, perm)
128 
129 /**
130  * module_param_unsafe - same as module_param but taints kernel
131  * @name: the variable to alter, and exposed parameter name.
132  * @type: the type of the parameter
133  * @perm: visibility in sysfs.
134  */
135 #define module_param_unsafe(name, type, perm)			\
136 	module_param_named_unsafe(name, name, type, perm)
137 
138 /**
139  * module_param_named - typesafe helper for a renamed module/cmdline parameter
140  * @name: a valid C identifier which is the parameter name.
141  * @value: the actual lvalue to alter.
142  * @type: the type of the parameter
143  * @perm: visibility in sysfs.
144  *
145  * Usually it's a good idea to have variable names and user-exposed names the
146  * same, but that's harder if the variable must be non-static or is inside a
147  * structure.  This allows exposure under a different name.
148  */
149 #define module_param_named(name, value, type, perm)			   \
150 	param_check_##type(name, &(value));				   \
151 	module_param_cb(name, &param_ops_##type, &value, perm);		   \
152 	__MODULE_PARM_TYPE(name, #type)
153 
154 /**
155  * module_param_named_unsafe - same as module_param_named but taints kernel
156  * @name: a valid C identifier which is the parameter name.
157  * @value: the actual lvalue to alter.
158  * @type: the type of the parameter
159  * @perm: visibility in sysfs.
160  */
161 #define module_param_named_unsafe(name, value, type, perm)		\
162 	param_check_##type(name, &(value));				\
163 	module_param_cb_unsafe(name, &param_ops_##type, &value, perm);	\
164 	__MODULE_PARM_TYPE(name, #type)
165 
166 /**
167  * module_param_cb - general callback for a module/cmdline parameter
168  * @name: a valid C identifier which is the parameter name.
169  * @ops: the set & get operations for this parameter.
170  * @arg: args for @ops
171  * @perm: visibility in sysfs.
172  *
173  * The ops can have NULL set or get functions.
174  */
175 #define module_param_cb(name, ops, arg, perm)				      \
176 	__module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, -1, 0)
177 
178 #define module_param_cb_unsafe(name, ops, arg, perm)			      \
179 	__module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, -1,    \
180 			    KERNEL_PARAM_FL_UNSAFE)
181 
182 #define __level_param_cb(name, ops, arg, perm, level)			\
183 	__module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, level, 0)
184 /**
185  * core_param_cb - general callback for a module/cmdline parameter
186  *                 to be evaluated before core initcall level
187  * @name: a valid C identifier which is the parameter name.
188  * @ops: the set & get operations for this parameter.
189  * @arg: args for @ops
190  * @perm: visibility in sysfs.
191  *
192  * The ops can have NULL set or get functions.
193  */
194 #define core_param_cb(name, ops, arg, perm)		\
195 	__level_param_cb(name, ops, arg, perm, 1)
196 
197 /**
198  * postcore_param_cb - general callback for a module/cmdline parameter
199  *                     to be evaluated before postcore initcall level
200  * @name: a valid C identifier which is the parameter name.
201  * @ops: the set & get operations for this parameter.
202  * @arg: args for @ops
203  * @perm: visibility in sysfs.
204  *
205  * The ops can have NULL set or get functions.
206  */
207 #define postcore_param_cb(name, ops, arg, perm)		\
208 	__level_param_cb(name, ops, arg, perm, 2)
209 
210 /**
211  * arch_param_cb - general callback for a module/cmdline parameter
212  *                 to be evaluated before arch initcall level
213  * @name: a valid C identifier which is the parameter name.
214  * @ops: the set & get operations for this parameter.
215  * @arg: args for @ops
216  * @perm: visibility in sysfs.
217  *
218  * The ops can have NULL set or get functions.
219  */
220 #define arch_param_cb(name, ops, arg, perm)		\
221 	__level_param_cb(name, ops, arg, perm, 3)
222 
223 /**
224  * subsys_param_cb - general callback for a module/cmdline parameter
225  *                   to be evaluated before subsys initcall level
226  * @name: a valid C identifier which is the parameter name.
227  * @ops: the set & get operations for this parameter.
228  * @arg: args for @ops
229  * @perm: visibility in sysfs.
230  *
231  * The ops can have NULL set or get functions.
232  */
233 #define subsys_param_cb(name, ops, arg, perm)		\
234 	__level_param_cb(name, ops, arg, perm, 4)
235 
236 /**
237  * fs_param_cb - general callback for a module/cmdline parameter
238  *               to be evaluated before fs initcall level
239  * @name: a valid C identifier which is the parameter name.
240  * @ops: the set & get operations for this parameter.
241  * @arg: args for @ops
242  * @perm: visibility in sysfs.
243  *
244  * The ops can have NULL set or get functions.
245  */
246 #define fs_param_cb(name, ops, arg, perm)		\
247 	__level_param_cb(name, ops, arg, perm, 5)
248 
249 /**
250  * device_param_cb - general callback for a module/cmdline parameter
251  *                   to be evaluated before device initcall level
252  * @name: a valid C identifier which is the parameter name.
253  * @ops: the set & get operations for this parameter.
254  * @arg: args for @ops
255  * @perm: visibility in sysfs.
256  *
257  * The ops can have NULL set or get functions.
258  */
259 #define device_param_cb(name, ops, arg, perm)		\
260 	__level_param_cb(name, ops, arg, perm, 6)
261 
262 /**
263  * late_param_cb - general callback for a module/cmdline parameter
264  *                 to be evaluated before late initcall level
265  * @name: a valid C identifier which is the parameter name.
266  * @ops: the set & get operations for this parameter.
267  * @arg: args for @ops
268  * @perm: visibility in sysfs.
269  *
270  * The ops can have NULL set or get functions.
271  */
272 #define late_param_cb(name, ops, arg, perm)		\
273 	__level_param_cb(name, ops, arg, perm, 7)
274 
275 /* On alpha, ia64 and ppc64 relocations to global data cannot go into
276    read-only sections (which is part of respective UNIX ABI on these
277    platforms). So 'const' makes no sense and even causes compile failures
278    with some compilers. */
279 #if defined(CONFIG_ALPHA) || defined(CONFIG_IA64) || defined(CONFIG_PPC64)
280 #define __moduleparam_const
281 #else
282 #define __moduleparam_const const
283 #endif
284 
285 /* This is the fundamental function for registering boot/module
286    parameters. */
287 #define __module_param_call(prefix, name, ops, arg, perm, level, flags)	\
288 	/* Default value instead of permissions? */			\
289 	static const char __param_str_##name[] = prefix #name;		\
290 	static struct kernel_param __moduleparam_const __param_##name	\
291 	__used __section("__param")					\
292 	__aligned(__alignof__(struct kernel_param))			\
293 	= { __param_str_##name, THIS_MODULE, ops,			\
294 	    VERIFY_OCTAL_PERMISSIONS(perm), level, flags, { arg } }
295 
296 /* Obsolete - use module_param_cb() */
297 #define module_param_call(name, _set, _get, arg, perm)			\
298 	static const struct kernel_param_ops __param_ops_##name =	\
299 		{ .flags = 0, .set = _set, .get = _get };		\
300 	__module_param_call(MODULE_PARAM_PREFIX,			\
301 			    name, &__param_ops_##name, arg, perm, -1, 0)
302 
303 #ifdef CONFIG_SYSFS
304 extern void kernel_param_lock(struct module *mod);
305 extern void kernel_param_unlock(struct module *mod);
306 #else
307 static inline void kernel_param_lock(struct module *mod)
308 {
309 }
310 static inline void kernel_param_unlock(struct module *mod)
311 {
312 }
313 #endif
314 
315 #ifndef MODULE
316 /**
317  * core_param - define a historical core kernel parameter.
318  * @name: the name of the cmdline and sysfs parameter (often the same as var)
319  * @var: the variable
320  * @type: the type of the parameter
321  * @perm: visibility in sysfs
322  *
323  * core_param is just like module_param(), but cannot be modular and
324  * doesn't add a prefix (such as "printk.").  This is for compatibility
325  * with __setup(), and it makes sense as truly core parameters aren't
326  * tied to the particular file they're in.
327  */
328 #define core_param(name, var, type, perm)				\
329 	param_check_##type(name, &(var));				\
330 	__module_param_call("", name, &param_ops_##type, &var, perm, -1, 0)
331 
332 /**
333  * core_param_unsafe - same as core_param but taints kernel
334  * @name: the name of the cmdline and sysfs parameter (often the same as var)
335  * @var: the variable
336  * @type: the type of the parameter
337  * @perm: visibility in sysfs
338  */
339 #define core_param_unsafe(name, var, type, perm)		\
340 	param_check_##type(name, &(var));				\
341 	__module_param_call("", name, &param_ops_##type, &var, perm,	\
342 			    -1, KERNEL_PARAM_FL_UNSAFE)
343 
344 #endif /* !MODULE */
345 
346 /**
347  * module_param_string - a char array parameter
348  * @name: the name of the parameter
349  * @string: the string variable
350  * @len: the maximum length of the string, incl. terminator
351  * @perm: visibility in sysfs.
352  *
353  * This actually copies the string when it's set (unlike type charp).
354  * @len is usually just sizeof(string).
355  */
356 #define module_param_string(name, string, len, perm)			\
357 	static const struct kparam_string __param_string_##name		\
358 		= { len, string };					\
359 	__module_param_call(MODULE_PARAM_PREFIX, name,			\
360 			    &param_ops_string,				\
361 			    .str = &__param_string_##name, perm, -1, 0);\
362 	__MODULE_PARM_TYPE(name, "string")
363 
364 /**
365  * parameq - checks if two parameter names match
366  * @name1: parameter name 1
367  * @name2: parameter name 2
368  *
369  * Returns true if the two parameter names are equal.
370  * Dashes (-) are considered equal to underscores (_).
371  */
372 extern bool parameq(const char *name1, const char *name2);
373 
374 /**
375  * parameqn - checks if two parameter names match
376  * @name1: parameter name 1
377  * @name2: parameter name 2
378  * @n: the length to compare
379  *
380  * Similar to parameq(), except it compares @n characters.
381  */
382 extern bool parameqn(const char *name1, const char *name2, size_t n);
383 
384 /* Called on module insert or kernel boot */
385 extern char *parse_args(const char *name,
386 		      char *args,
387 		      const struct kernel_param *params,
388 		      unsigned num,
389 		      s16 level_min,
390 		      s16 level_max,
391 		      void *arg,
392 		      int (*unknown)(char *param, char *val,
393 				     const char *doing, void *arg));
394 
395 /* Called by module remove. */
396 #ifdef CONFIG_SYSFS
397 extern void destroy_params(const struct kernel_param *params, unsigned num);
398 #else
399 static inline void destroy_params(const struct kernel_param *params,
400 				  unsigned num)
401 {
402 }
403 #endif /* !CONFIG_SYSFS */
404 
405 /* All the helper functions */
406 /* The macros to do compile-time type checking stolen from Jakub
407    Jelinek, who IIRC came up with this idea for the 2.4 module init code. */
408 #define __param_check(name, p, type) \
409 	static inline type __always_unused *__check_##name(void) { return(p); }
410 
411 extern const struct kernel_param_ops param_ops_byte;
412 extern int param_set_byte(const char *val, const struct kernel_param *kp);
413 extern int param_get_byte(char *buffer, const struct kernel_param *kp);
414 #define param_check_byte(name, p) __param_check(name, p, unsigned char)
415 
416 extern const struct kernel_param_ops param_ops_short;
417 extern int param_set_short(const char *val, const struct kernel_param *kp);
418 extern int param_get_short(char *buffer, const struct kernel_param *kp);
419 #define param_check_short(name, p) __param_check(name, p, short)
420 
421 extern const struct kernel_param_ops param_ops_ushort;
422 extern int param_set_ushort(const char *val, const struct kernel_param *kp);
423 extern int param_get_ushort(char *buffer, const struct kernel_param *kp);
424 #define param_check_ushort(name, p) __param_check(name, p, unsigned short)
425 
426 extern const struct kernel_param_ops param_ops_int;
427 extern int param_set_int(const char *val, const struct kernel_param *kp);
428 extern int param_get_int(char *buffer, const struct kernel_param *kp);
429 #define param_check_int(name, p) __param_check(name, p, int)
430 
431 extern const struct kernel_param_ops param_ops_uint;
432 extern int param_set_uint(const char *val, const struct kernel_param *kp);
433 extern int param_get_uint(char *buffer, const struct kernel_param *kp);
434 int param_set_uint_minmax(const char *val, const struct kernel_param *kp,
435 		unsigned int min, unsigned int max);
436 #define param_check_uint(name, p) __param_check(name, p, unsigned int)
437 
438 extern const struct kernel_param_ops param_ops_long;
439 extern int param_set_long(const char *val, const struct kernel_param *kp);
440 extern int param_get_long(char *buffer, const struct kernel_param *kp);
441 #define param_check_long(name, p) __param_check(name, p, long)
442 
443 extern const struct kernel_param_ops param_ops_ulong;
444 extern int param_set_ulong(const char *val, const struct kernel_param *kp);
445 extern int param_get_ulong(char *buffer, const struct kernel_param *kp);
446 #define param_check_ulong(name, p) __param_check(name, p, unsigned long)
447 
448 extern const struct kernel_param_ops param_ops_ullong;
449 extern int param_set_ullong(const char *val, const struct kernel_param *kp);
450 extern int param_get_ullong(char *buffer, const struct kernel_param *kp);
451 #define param_check_ullong(name, p) __param_check(name, p, unsigned long long)
452 
453 extern const struct kernel_param_ops param_ops_hexint;
454 extern int param_set_hexint(const char *val, const struct kernel_param *kp);
455 extern int param_get_hexint(char *buffer, const struct kernel_param *kp);
456 #define param_check_hexint(name, p) param_check_uint(name, p)
457 
458 extern const struct kernel_param_ops param_ops_charp;
459 extern int param_set_charp(const char *val, const struct kernel_param *kp);
460 extern int param_get_charp(char *buffer, const struct kernel_param *kp);
461 extern void param_free_charp(void *arg);
462 #define param_check_charp(name, p) __param_check(name, p, char *)
463 
464 /* We used to allow int as well as bool.  We're taking that away! */
465 extern const struct kernel_param_ops param_ops_bool;
466 extern int param_set_bool(const char *val, const struct kernel_param *kp);
467 extern int param_get_bool(char *buffer, const struct kernel_param *kp);
468 #define param_check_bool(name, p) __param_check(name, p, bool)
469 
470 extern const struct kernel_param_ops param_ops_bool_enable_only;
471 extern int param_set_bool_enable_only(const char *val,
472 				      const struct kernel_param *kp);
473 /* getter is the same as for the regular bool */
474 #define param_check_bool_enable_only param_check_bool
475 
476 extern const struct kernel_param_ops param_ops_invbool;
477 extern int param_set_invbool(const char *val, const struct kernel_param *kp);
478 extern int param_get_invbool(char *buffer, const struct kernel_param *kp);
479 #define param_check_invbool(name, p) __param_check(name, p, bool)
480 
481 /* An int, which can only be set like a bool (though it shows as an int). */
482 extern const struct kernel_param_ops param_ops_bint;
483 extern int param_set_bint(const char *val, const struct kernel_param *kp);
484 #define param_get_bint param_get_int
485 #define param_check_bint param_check_int
486 
487 /**
488  * module_param_array - a parameter which is an array of some type
489  * @name: the name of the array variable
490  * @type: the type, as per module_param()
491  * @nump: optional pointer filled in with the number written
492  * @perm: visibility in sysfs
493  *
494  * Input and output are as comma-separated values.  Commas inside values
495  * don't work properly (eg. an array of charp).
496  *
497  * ARRAY_SIZE(@name) is used to determine the number of elements in the
498  * array, so the definition must be visible.
499  */
500 #define module_param_array(name, type, nump, perm)		\
501 	module_param_array_named(name, name, type, nump, perm)
502 
503 /**
504  * module_param_array_named - renamed parameter which is an array of some type
505  * @name: a valid C identifier which is the parameter name
506  * @array: the name of the array variable
507  * @type: the type, as per module_param()
508  * @nump: optional pointer filled in with the number written
509  * @perm: visibility in sysfs
510  *
511  * This exposes a different name than the actual variable name.  See
512  * module_param_named() for why this might be necessary.
513  */
514 #define module_param_array_named(name, array, type, nump, perm)		\
515 	param_check_##type(name, &(array)[0]);				\
516 	static const struct kparam_array __param_arr_##name		\
517 	= { .max = ARRAY_SIZE(array), .num = nump,                      \
518 	    .ops = &param_ops_##type,					\
519 	    .elemsize = sizeof(array[0]), .elem = array };		\
520 	__module_param_call(MODULE_PARAM_PREFIX, name,			\
521 			    &param_array_ops,				\
522 			    .arr = &__param_arr_##name,			\
523 			    perm, -1, 0);				\
524 	__MODULE_PARM_TYPE(name, "array of " #type)
525 
526 enum hwparam_type {
527 	hwparam_ioport,		/* Module parameter configures an I/O port */
528 	hwparam_iomem,		/* Module parameter configures an I/O mem address */
529 	hwparam_ioport_or_iomem, /* Module parameter could be either, depending on other option */
530 	hwparam_irq,		/* Module parameter configures an IRQ */
531 	hwparam_dma,		/* Module parameter configures a DMA channel */
532 	hwparam_dma_addr,	/* Module parameter configures a DMA buffer address */
533 	hwparam_other,		/* Module parameter configures some other value */
534 };
535 
536 /**
537  * module_param_hw_named - A parameter representing a hw parameters
538  * @name: a valid C identifier which is the parameter name.
539  * @value: the actual lvalue to alter.
540  * @type: the type of the parameter
541  * @hwtype: what the value represents (enum hwparam_type)
542  * @perm: visibility in sysfs.
543  *
544  * Usually it's a good idea to have variable names and user-exposed names the
545  * same, but that's harder if the variable must be non-static or is inside a
546  * structure.  This allows exposure under a different name.
547  */
548 #define module_param_hw_named(name, value, type, hwtype, perm)		\
549 	param_check_##type(name, &(value));				\
550 	__module_param_call(MODULE_PARAM_PREFIX, name,			\
551 			    &param_ops_##type, &value,			\
552 			    perm, -1,					\
553 			    KERNEL_PARAM_FL_HWPARAM | (hwparam_##hwtype & 0));	\
554 	__MODULE_PARM_TYPE(name, #type)
555 
556 #define module_param_hw(name, type, hwtype, perm)		\
557 	module_param_hw_named(name, name, type, hwtype, perm)
558 
559 /**
560  * module_param_hw_array - A parameter representing an array of hw parameters
561  * @name: the name of the array variable
562  * @type: the type, as per module_param()
563  * @hwtype: what the value represents (enum hwparam_type)
564  * @nump: optional pointer filled in with the number written
565  * @perm: visibility in sysfs
566  *
567  * Input and output are as comma-separated values.  Commas inside values
568  * don't work properly (eg. an array of charp).
569  *
570  * ARRAY_SIZE(@name) is used to determine the number of elements in the
571  * array, so the definition must be visible.
572  */
573 #define module_param_hw_array(name, type, hwtype, nump, perm)		\
574 	param_check_##type(name, &(name)[0]);				\
575 	static const struct kparam_array __param_arr_##name		\
576 	= { .max = ARRAY_SIZE(name), .num = nump,			\
577 	    .ops = &param_ops_##type,					\
578 	    .elemsize = sizeof(name[0]), .elem = name };		\
579 	__module_param_call(MODULE_PARAM_PREFIX, name,			\
580 			    &param_array_ops,				\
581 			    .arr = &__param_arr_##name,			\
582 			    perm, -1,					\
583 			    KERNEL_PARAM_FL_HWPARAM | (hwparam_##hwtype & 0));	\
584 	__MODULE_PARM_TYPE(name, "array of " #type)
585 
586 
587 extern const struct kernel_param_ops param_array_ops;
588 
589 extern const struct kernel_param_ops param_ops_string;
590 extern int param_set_copystring(const char *val, const struct kernel_param *);
591 extern int param_get_string(char *buffer, const struct kernel_param *kp);
592 
593 /* for exporting parameters in /sys/module/.../parameters */
594 
595 struct module;
596 
597 #if defined(CONFIG_SYSFS) && defined(CONFIG_MODULES)
598 extern int module_param_sysfs_setup(struct module *mod,
599 				    const struct kernel_param *kparam,
600 				    unsigned int num_params);
601 
602 extern void module_param_sysfs_remove(struct module *mod);
603 #else
604 static inline int module_param_sysfs_setup(struct module *mod,
605 			     const struct kernel_param *kparam,
606 			     unsigned int num_params)
607 {
608 	return 0;
609 }
610 
611 static inline void module_param_sysfs_remove(struct module *mod)
612 { }
613 #endif
614 
615 #endif /* _LINUX_MODULE_PARAMS_H */
616