Add module param type 'ullong'
[linux-2.6-block.git] / include / linux / moduleparam.h
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1da177e4
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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 "."
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14#endif
15
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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 21static const char __UNIQUE_ID(name)[] \
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22 __used __attribute__((section(".modinfo"), unused, aligned(1))) \
23 = __stringify(tag) "=" info
1da177e4 24#else /* !MODULE */
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25/* This struct is here for syntactic coherency, it is not used */
26#define __MODULE_INFO(tag, name, info) \
34182eea 27 struct __UNIQUE_ID(name) {}
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28#endif
29#define __MODULE_PARM_TYPE(name, _type) \
30 __MODULE_INFO(parmtype, name##type, #name ":" _type)
31
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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
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37struct kernel_param;
38
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39/*
40 * Flags available for kernel_param_ops
41 *
42 * NOARG - the parameter allows for no argument (foo instead of foo=1)
43 */
44enum {
45 KERNEL_PARAM_FL_NOARG = (1 << 0)
46};
47
9bbb9e5a 48struct kernel_param_ops {
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49 /* How the ops should behave */
50 unsigned int flags;
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51 /* Returns 0, or -errno. arg is in kp->arg. */
52 int (*set)(const char *val, const struct kernel_param *kp);
53 /* Returns length written or -errno. Buffer is 4k (ie. be short!) */
54 int (*get)(char *buffer, const struct kernel_param *kp);
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55 /* Optional function to free kp->arg when module unloaded. */
56 void (*free)(void *arg);
9bbb9e5a 57};
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58
59struct kernel_param {
60 const char *name;
9bbb9e5a 61 const struct kernel_param_ops *ops;
45fcc70c 62 u16 perm;
026cee00 63 s16 level;
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64 union {
65 void *arg;
66 const struct kparam_string *str;
67 const struct kparam_array *arr;
68 };
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69};
70
71/* Special one for strings we want to copy into */
72struct kparam_string {
73 unsigned int maxlen;
74 char *string;
75};
76
77/* Special one for arrays */
78struct kparam_array
79{
80 unsigned int max;
c5be0b2e 81 unsigned int elemsize;
1da177e4 82 unsigned int *num;
9bbb9e5a 83 const struct kernel_param_ops *ops;
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84 void *elem;
85};
86
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87/**
88 * module_param - typesafe helper for a module/cmdline parameter
89 * @value: the variable to alter, and exposed parameter name.
90 * @type: the type of the parameter
91 * @perm: visibility in sysfs.
92 *
93 * @value becomes the module parameter, or (prefixed by KBUILD_MODNAME and a
94 * ".") the kernel commandline parameter. Note that - is changed to _, so
95 * the user can use "foo-bar=1" even for variable "foo_bar".
96 *
97 * @perm is 0 if the the variable is not to appear in sysfs, or 0444
98 * for world-readable, 0644 for root-writable, etc. Note that if it
99 * is writable, you may need to use kparam_block_sysfs_write() around
100 * accesses (esp. charp, which can be kfreed when it changes).
101 *
102 * The @type is simply pasted to refer to a param_ops_##type and a
103 * param_check_##type: for convenience many standard types are provided but
104 * you can create your own by defining those variables.
105 *
106 * Standard types are:
107 * byte, short, ushort, int, uint, long, ulong
108 * charp: a character pointer
109 * bool: a bool, values 0/1, y/n, Y/N.
110 * invbool: the above, only sense-reversed (N = true).
111 */
112#define module_param(name, type, perm) \
113 module_param_named(name, name, type, perm)
114
115/**
116 * module_param_named - typesafe helper for a renamed module/cmdline parameter
117 * @name: a valid C identifier which is the parameter name.
118 * @value: the actual lvalue to alter.
119 * @type: the type of the parameter
120 * @perm: visibility in sysfs.
121 *
122 * Usually it's a good idea to have variable names and user-exposed names the
123 * same, but that's harder if the variable must be non-static or is inside a
124 * structure. This allows exposure under a different name.
125 */
126#define module_param_named(name, value, type, perm) \
127 param_check_##type(name, &(value)); \
128 module_param_cb(name, &param_ops_##type, &value, perm); \
129 __MODULE_PARM_TYPE(name, #type)
130
131/**
132 * module_param_cb - general callback for a module/cmdline parameter
133 * @name: a valid C identifier which is the parameter name.
134 * @ops: the set & get operations for this parameter.
135 * @perm: visibility in sysfs.
136 *
137 * The ops can have NULL set or get functions.
138 */
139#define module_param_cb(name, ops, arg, perm) \
ae82fdb1 140 __module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, -1)
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141
142/**
143 * <level>_param_cb - general callback for a module/cmdline parameter
144 * to be evaluated before certain initcall level
145 * @name: a valid C identifier which is the parameter name.
146 * @ops: the set & get operations for this parameter.
147 * @perm: visibility in sysfs.
148 *
149 * The ops can have NULL set or get functions.
150 */
151#define __level_param_cb(name, ops, arg, perm, level) \
152 __module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, level)
153
154#define core_param_cb(name, ops, arg, perm) \
155 __level_param_cb(name, ops, arg, perm, 1)
156
157#define postcore_param_cb(name, ops, arg, perm) \
158 __level_param_cb(name, ops, arg, perm, 2)
159
160#define arch_param_cb(name, ops, arg, perm) \
161 __level_param_cb(name, ops, arg, perm, 3)
162
163#define subsys_param_cb(name, ops, arg, perm) \
164 __level_param_cb(name, ops, arg, perm, 4)
165
166#define fs_param_cb(name, ops, arg, perm) \
167 __level_param_cb(name, ops, arg, perm, 5)
168
169#define device_param_cb(name, ops, arg, perm) \
170 __level_param_cb(name, ops, arg, perm, 6)
171
172#define late_param_cb(name, ops, arg, perm) \
173 __level_param_cb(name, ops, arg, perm, 7)
546970bc 174
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175/* On alpha, ia64 and ppc64 relocations to global data cannot go into
176 read-only sections (which is part of respective UNIX ABI on these
177 platforms). So 'const' makes no sense and even causes compile failures
178 with some compilers. */
179#if defined(CONFIG_ALPHA) || defined(CONFIG_IA64) || defined(CONFIG_PPC64)
180#define __moduleparam_const
181#else
182#define __moduleparam_const const
183#endif
184
1da177e4 185/* This is the fundamental function for registering boot/module
546970bc 186 parameters. */
026cee00 187#define __module_param_call(prefix, name, ops, arg, perm, level) \
9774a1f5 188 /* Default value instead of permissions? */ \
58f86cc8 189 static const char __param_str_##name[] = prefix #name; \
91d35dd9 190 static struct kernel_param __moduleparam_const __param_##name \
3ff6eecc 191 __used \
1da177e4 192 __attribute__ ((unused,__section__ ("__param"),aligned(sizeof(void *)))) \
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193 = { __param_str_##name, ops, VERIFY_OCTAL_PERMISSIONS(perm), \
194 level, { arg } }
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195
196/* Obsolete - use module_param_cb() */
197#define module_param_call(name, set, get, arg, perm) \
198 static struct kernel_param_ops __param_ops_##name = \
ab013c5f 199 { 0, (void *)set, (void *)get }; \
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200 __module_param_call(MODULE_PARAM_PREFIX, \
201 name, &__param_ops_##name, arg, \
ae82fdb1 202 (perm) + sizeof(__check_old_set_param(set))*0, -1)
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203
204/* We don't get oldget: it's often a new-style param_get_uint, etc. */
205static inline int
206__check_old_set_param(int (*oldset)(const char *, struct kernel_param *))
207{
208 return 0;
209}
1da177e4 210
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211/**
212 * kparam_block_sysfs_write - make sure a parameter isn't written via sysfs.
213 * @name: the name of the parameter
214 *
215 * There's no point blocking write on a paramter that isn't writable via sysfs!
216 */
217#define kparam_block_sysfs_write(name) \
218 do { \
219 BUG_ON(!(__param_##name.perm & 0222)); \
220 __kernel_param_lock(); \
221 } while (0)
222
223/**
224 * kparam_unblock_sysfs_write - allows sysfs to write to a parameter again.
225 * @name: the name of the parameter
226 */
227#define kparam_unblock_sysfs_write(name) \
228 do { \
229 BUG_ON(!(__param_##name.perm & 0222)); \
230 __kernel_param_unlock(); \
231 } while (0)
232
233/**
234 * kparam_block_sysfs_read - make sure a parameter isn't read via sysfs.
235 * @name: the name of the parameter
236 *
237 * This also blocks sysfs writes.
238 */
239#define kparam_block_sysfs_read(name) \
240 do { \
241 BUG_ON(!(__param_##name.perm & 0444)); \
242 __kernel_param_lock(); \
243 } while (0)
244
245/**
246 * kparam_unblock_sysfs_read - allows sysfs to read a parameter again.
247 * @name: the name of the parameter
248 */
249#define kparam_unblock_sysfs_read(name) \
250 do { \
251 BUG_ON(!(__param_##name.perm & 0444)); \
252 __kernel_param_unlock(); \
253 } while (0)
254
255#ifdef CONFIG_SYSFS
256extern void __kernel_param_lock(void);
257extern void __kernel_param_unlock(void);
258#else
259static inline void __kernel_param_lock(void)
260{
261}
262static inline void __kernel_param_unlock(void)
263{
264}
265#endif
266
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267#ifndef MODULE
268/**
269 * core_param - define a historical core kernel parameter.
270 * @name: the name of the cmdline and sysfs parameter (often the same as var)
271 * @var: the variable
546970bc 272 * @type: the type of the parameter
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273 * @perm: visibility in sysfs
274 *
275 * core_param is just like module_param(), but cannot be modular and
276 * doesn't add a prefix (such as "printk."). This is for compatibility
277 * with __setup(), and it makes sense as truly core parameters aren't
278 * tied to the particular file they're in.
279 */
280#define core_param(name, var, type, perm) \
281 param_check_##type(name, &(var)); \
ae82fdb1 282 __module_param_call("", name, &param_ops_##type, &var, perm, -1)
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283#endif /* !MODULE */
284
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285/**
286 * module_param_string - a char array parameter
287 * @name: the name of the parameter
288 * @string: the string variable
289 * @len: the maximum length of the string, incl. terminator
290 * @perm: visibility in sysfs.
291 *
292 * This actually copies the string when it's set (unlike type charp).
293 * @len is usually just sizeof(string).
294 */
1da177e4 295#define module_param_string(name, string, len, perm) \
22e48eaf 296 static const struct kparam_string __param_string_##name \
1da177e4 297 = { len, string }; \
fddd5201 298 __module_param_call(MODULE_PARAM_PREFIX, name, \
9bbb9e5a 299 &param_ops_string, \
ae82fdb1 300 .str = &__param_string_##name, perm, -1); \
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301 __MODULE_PARM_TYPE(name, "string")
302
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303/**
304 * parameq - checks if two parameter names match
305 * @name1: parameter name 1
306 * @name2: parameter name 2
307 *
308 * Returns true if the two parameter names are equal.
309 * Dashes (-) are considered equal to underscores (_).
310 */
311extern bool parameq(const char *name1, const char *name2);
312
313/**
314 * parameqn - checks if two parameter names match
315 * @name1: parameter name 1
316 * @name2: parameter name 2
317 * @n: the length to compare
318 *
319 * Similar to parameq(), except it compares @n characters.
320 */
321extern bool parameqn(const char *name1, const char *name2, size_t n);
322
1da177e4 323/* Called on module insert or kernel boot */
51e158c1 324extern char *parse_args(const char *name,
1da177e4 325 char *args,
914dcaa8 326 const struct kernel_param *params,
1da177e4 327 unsigned num,
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328 s16 level_min,
329 s16 level_max,
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330 int (*unknown)(char *param, char *val,
331 const char *doing));
1da177e4 332
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333/* Called by module remove. */
334#ifdef CONFIG_SYSFS
335extern void destroy_params(const struct kernel_param *params, unsigned num);
336#else
337static inline void destroy_params(const struct kernel_param *params,
338 unsigned num)
339{
340}
341#endif /* !CONFIG_SYSFS */
342
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343/* All the helper functions */
344/* The macros to do compile-time type checking stolen from Jakub
345 Jelinek, who IIRC came up with this idea for the 2.4 module init code. */
346#define __param_check(name, p, type) \
0283f9a5 347 static inline type __always_unused *__check_##name(void) { return(p); }
1da177e4 348
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349extern struct kernel_param_ops param_ops_byte;
350extern int param_set_byte(const char *val, const struct kernel_param *kp);
351extern int param_get_byte(char *buffer, const struct kernel_param *kp);
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352#define param_check_byte(name, p) __param_check(name, p, unsigned char)
353
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354extern struct kernel_param_ops param_ops_short;
355extern int param_set_short(const char *val, const struct kernel_param *kp);
356extern int param_get_short(char *buffer, const struct kernel_param *kp);
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357#define param_check_short(name, p) __param_check(name, p, short)
358
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359extern struct kernel_param_ops param_ops_ushort;
360extern int param_set_ushort(const char *val, const struct kernel_param *kp);
361extern int param_get_ushort(char *buffer, const struct kernel_param *kp);
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362#define param_check_ushort(name, p) __param_check(name, p, unsigned short)
363
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364extern struct kernel_param_ops param_ops_int;
365extern int param_set_int(const char *val, const struct kernel_param *kp);
366extern int param_get_int(char *buffer, const struct kernel_param *kp);
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367#define param_check_int(name, p) __param_check(name, p, int)
368
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369extern struct kernel_param_ops param_ops_uint;
370extern int param_set_uint(const char *val, const struct kernel_param *kp);
371extern int param_get_uint(char *buffer, const struct kernel_param *kp);
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372#define param_check_uint(name, p) __param_check(name, p, unsigned int)
373
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374extern struct kernel_param_ops param_ops_long;
375extern int param_set_long(const char *val, const struct kernel_param *kp);
376extern int param_get_long(char *buffer, const struct kernel_param *kp);
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377#define param_check_long(name, p) __param_check(name, p, long)
378
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379extern struct kernel_param_ops param_ops_ulong;
380extern int param_set_ulong(const char *val, const struct kernel_param *kp);
381extern int param_get_ulong(char *buffer, const struct kernel_param *kp);
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382#define param_check_ulong(name, p) __param_check(name, p, unsigned long)
383
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384extern struct kernel_param_ops param_ops_ullong;
385extern int param_set_ullong(const char *val, const struct kernel_param *kp);
386extern int param_get_ullong(char *buffer, const struct kernel_param *kp);
387#define param_check_ullong(name, p) __param_check(name, p, unsigned long long)
388
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389extern struct kernel_param_ops param_ops_charp;
390extern int param_set_charp(const char *val, const struct kernel_param *kp);
391extern int param_get_charp(char *buffer, const struct kernel_param *kp);
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392#define param_check_charp(name, p) __param_check(name, p, char *)
393
72db395f 394/* We used to allow int as well as bool. We're taking that away! */
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395extern struct kernel_param_ops param_ops_bool;
396extern int param_set_bool(const char *val, const struct kernel_param *kp);
397extern int param_get_bool(char *buffer, const struct kernel_param *kp);
72db395f 398#define param_check_bool(name, p) __param_check(name, p, bool)
1da177e4 399
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400extern struct kernel_param_ops param_ops_invbool;
401extern int param_set_invbool(const char *val, const struct kernel_param *kp);
402extern int param_get_invbool(char *buffer, const struct kernel_param *kp);
9a71af2c 403#define param_check_invbool(name, p) __param_check(name, p, bool)
1da177e4 404
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405/* An int, which can only be set like a bool (though it shows as an int). */
406extern struct kernel_param_ops param_ops_bint;
407extern int param_set_bint(const char *val, const struct kernel_param *kp);
408#define param_get_bint param_get_int
409#define param_check_bint param_check_int
410
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411/**
412 * module_param_array - a parameter which is an array of some type
413 * @name: the name of the array variable
414 * @type: the type, as per module_param()
415 * @nump: optional pointer filled in with the number written
416 * @perm: visibility in sysfs
417 *
418 * Input and output are as comma-separated values. Commas inside values
419 * don't work properly (eg. an array of charp).
420 *
421 * ARRAY_SIZE(@name) is used to determine the number of elements in the
422 * array, so the definition must be visible.
423 */
424#define module_param_array(name, type, nump, perm) \
425 module_param_array_named(name, name, type, nump, perm)
426
427/**
428 * module_param_array_named - renamed parameter which is an array of some type
429 * @name: a valid C identifier which is the parameter name
430 * @array: the name of the array variable
431 * @type: the type, as per module_param()
432 * @nump: optional pointer filled in with the number written
433 * @perm: visibility in sysfs
434 *
435 * This exposes a different name than the actual variable name. See
436 * module_param_named() for why this might be necessary.
437 */
1da177e4 438#define module_param_array_named(name, array, type, nump, perm) \
bafeafea 439 param_check_##type(name, &(array)[0]); \
22e48eaf 440 static const struct kparam_array __param_arr_##name \
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441 = { .max = ARRAY_SIZE(array), .num = nump, \
442 .ops = &param_ops_##type, \
443 .elemsize = sizeof(array[0]), .elem = array }; \
fddd5201 444 __module_param_call(MODULE_PARAM_PREFIX, name, \
9bbb9e5a 445 &param_array_ops, \
fddd5201 446 .arr = &__param_arr_##name, \
ae82fdb1 447 perm, -1); \
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448 __MODULE_PARM_TYPE(name, "array of " #type)
449
9bbb9e5a 450extern struct kernel_param_ops param_array_ops;
1da177e4 451
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452extern struct kernel_param_ops param_ops_string;
453extern int param_set_copystring(const char *val, const struct kernel_param *);
454extern int param_get_string(char *buffer, const struct kernel_param *kp);
1da177e4 455
b634d130 456/* for exporting parameters in /sys/module/.../parameters */
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457
458struct module;
459
ef665c1a 460#if defined(CONFIG_SYSFS) && defined(CONFIG_MODULES)
1da177e4 461extern int module_param_sysfs_setup(struct module *mod,
9bbb9e5a 462 const struct kernel_param *kparam,
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463 unsigned int num_params);
464
465extern void module_param_sysfs_remove(struct module *mod);
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466#else
467static inline int module_param_sysfs_setup(struct module *mod,
9bbb9e5a 468 const struct kernel_param *kparam,
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469 unsigned int num_params)
470{
471 return 0;
472}
473
474static inline void module_param_sysfs_remove(struct module *mod)
475{ }
476#endif
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477
478#endif /* _LINUX_MODULE_PARAMS_H */