Linux kernel mirror (for testing)
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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
13#define MODULE_PARAM_PREFIX KBUILD_MODNAME "."
14#endif
15
16/* Chosen so that structs with an unsigned long line up. */
17#define MAX_PARAM_PREFIX_LEN (64 - sizeof(unsigned long))
18
19#ifdef MODULE
20#define ___module_cat(a,b) __mod_ ## a ## b
21#define __module_cat(a,b) ___module_cat(a,b)
22#define __MODULE_INFO(tag, name, info) \
23static const char __module_cat(name,__LINE__)[] \
24 __used \
25 __attribute__((section(".modinfo"),unused)) = __stringify(tag) "=" info
26#else /* !MODULE */
27#define __MODULE_INFO(tag, name, info)
28#endif
29#define __MODULE_PARM_TYPE(name, _type) \
30 __MODULE_INFO(parmtype, name##type, #name ":" _type)
31
32struct kernel_param;
33
34/* Returns 0, or -errno. arg is in kp->arg. */
35typedef int (*param_set_fn)(const char *val, struct kernel_param *kp);
36/* Returns length written or -errno. Buffer is 4k (ie. be short!) */
37typedef int (*param_get_fn)(char *buffer, struct kernel_param *kp);
38
39/* Flag bits for kernel_param.flags */
40#define KPARAM_KMALLOCED 1
41#define KPARAM_ISBOOL 2
42
43struct kernel_param {
44 const char *name;
45 u16 perm;
46 u16 flags;
47 param_set_fn set;
48 param_get_fn get;
49 union {
50 void *arg;
51 const struct kparam_string *str;
52 const struct kparam_array *arr;
53 };
54};
55
56/* Special one for strings we want to copy into */
57struct kparam_string {
58 unsigned int maxlen;
59 char *string;
60};
61
62/* Special one for arrays */
63struct kparam_array
64{
65 unsigned int max;
66 unsigned int *num;
67 param_set_fn set;
68 param_get_fn get;
69 unsigned int elemsize;
70 void *elem;
71};
72
73/* On alpha, ia64 and ppc64 relocations to global data cannot go into
74 read-only sections (which is part of respective UNIX ABI on these
75 platforms). So 'const' makes no sense and even causes compile failures
76 with some compilers. */
77#if defined(CONFIG_ALPHA) || defined(CONFIG_IA64) || defined(CONFIG_PPC64)
78#define __moduleparam_const
79#else
80#define __moduleparam_const const
81#endif
82
83/* This is the fundamental function for registering boot/module
84 parameters. perm sets the visibility in sysfs: 000 means it's
85 not there, read bits mean it's readable, write bits mean it's
86 writable. */
87#define __module_param_call(prefix, name, set, get, arg, isbool, perm) \
88 /* Default value instead of permissions? */ \
89 static int __param_perm_check_##name __attribute__((unused)) = \
90 BUILD_BUG_ON_ZERO((perm) < 0 || (perm) > 0777 || ((perm) & 2)) \
91 + BUILD_BUG_ON_ZERO(sizeof(""prefix) > MAX_PARAM_PREFIX_LEN); \
92 static const char __param_str_##name[] = prefix #name; \
93 static struct kernel_param __moduleparam_const __param_##name \
94 __used \
95 __attribute__ ((unused,__section__ ("__param"),aligned(sizeof(void *)))) \
96 = { __param_str_##name, perm, isbool ? KPARAM_ISBOOL : 0, \
97 set, get, { arg } }
98
99#define module_param_call(name, set, get, arg, perm) \
100 __module_param_call(MODULE_PARAM_PREFIX, \
101 name, set, get, arg, \
102 __same_type(*(arg), bool), perm)
103
104/* Helper functions: type is byte, short, ushort, int, uint, long,
105 ulong, charp, bool or invbool, or XXX if you define param_get_XXX,
106 param_set_XXX and param_check_XXX. */
107#define module_param_named(name, value, type, perm) \
108 param_check_##type(name, &(value)); \
109 module_param_call(name, param_set_##type, param_get_##type, &value, perm); \
110 __MODULE_PARM_TYPE(name, #type)
111
112#define module_param(name, type, perm) \
113 module_param_named(name, name, type, perm)
114
115#ifndef MODULE
116/**
117 * core_param - define a historical core kernel parameter.
118 * @name: the name of the cmdline and sysfs parameter (often the same as var)
119 * @var: the variable
120 * @type: the type (for param_set_##type and param_get_##type)
121 * @perm: visibility in sysfs
122 *
123 * core_param is just like module_param(), but cannot be modular and
124 * doesn't add a prefix (such as "printk."). This is for compatibility
125 * with __setup(), and it makes sense as truly core parameters aren't
126 * tied to the particular file they're in.
127 */
128#define core_param(name, var, type, perm) \
129 param_check_##type(name, &(var)); \
130 __module_param_call("", name, param_set_##type, param_get_##type, \
131 &var, __same_type(var, bool), perm)
132#endif /* !MODULE */
133
134/* Actually copy string: maxlen param is usually sizeof(string). */
135#define module_param_string(name, string, len, perm) \
136 static const struct kparam_string __param_string_##name \
137 = { len, string }; \
138 __module_param_call(MODULE_PARAM_PREFIX, name, \
139 param_set_copystring, param_get_string, \
140 .str = &__param_string_##name, 0, perm); \
141 __MODULE_PARM_TYPE(name, "string")
142
143/* Called on module insert or kernel boot */
144extern int parse_args(const char *name,
145 char *args,
146 struct kernel_param *params,
147 unsigned num,
148 int (*unknown)(char *param, char *val));
149
150/* Called by module remove. */
151#ifdef CONFIG_SYSFS
152extern void destroy_params(const struct kernel_param *params, unsigned num);
153#else
154static inline void destroy_params(const struct kernel_param *params,
155 unsigned num)
156{
157}
158#endif /* !CONFIG_SYSFS */
159
160/* All the helper functions */
161/* The macros to do compile-time type checking stolen from Jakub
162 Jelinek, who IIRC came up with this idea for the 2.4 module init code. */
163#define __param_check(name, p, type) \
164 static inline type *__check_##name(void) { return(p); }
165
166extern int param_set_byte(const char *val, struct kernel_param *kp);
167extern int param_get_byte(char *buffer, struct kernel_param *kp);
168#define param_check_byte(name, p) __param_check(name, p, unsigned char)
169
170extern int param_set_short(const char *val, struct kernel_param *kp);
171extern int param_get_short(char *buffer, struct kernel_param *kp);
172#define param_check_short(name, p) __param_check(name, p, short)
173
174extern int param_set_ushort(const char *val, struct kernel_param *kp);
175extern int param_get_ushort(char *buffer, struct kernel_param *kp);
176#define param_check_ushort(name, p) __param_check(name, p, unsigned short)
177
178extern int param_set_int(const char *val, struct kernel_param *kp);
179extern int param_get_int(char *buffer, struct kernel_param *kp);
180#define param_check_int(name, p) __param_check(name, p, int)
181
182extern int param_set_uint(const char *val, struct kernel_param *kp);
183extern int param_get_uint(char *buffer, struct kernel_param *kp);
184#define param_check_uint(name, p) __param_check(name, p, unsigned int)
185
186extern int param_set_long(const char *val, struct kernel_param *kp);
187extern int param_get_long(char *buffer, struct kernel_param *kp);
188#define param_check_long(name, p) __param_check(name, p, long)
189
190extern int param_set_ulong(const char *val, struct kernel_param *kp);
191extern int param_get_ulong(char *buffer, struct kernel_param *kp);
192#define param_check_ulong(name, p) __param_check(name, p, unsigned long)
193
194extern int param_set_charp(const char *val, struct kernel_param *kp);
195extern int param_get_charp(char *buffer, struct kernel_param *kp);
196#define param_check_charp(name, p) __param_check(name, p, char *)
197
198/* For historical reasons "bool" parameters can be (unsigned) "int". */
199extern int param_set_bool(const char *val, struct kernel_param *kp);
200extern int param_get_bool(char *buffer, struct kernel_param *kp);
201#define param_check_bool(name, p) \
202 static inline void __check_##name(void) \
203 { \
204 BUILD_BUG_ON(!__same_type(*(p), bool) && \
205 !__same_type(*(p), unsigned int) && \
206 !__same_type(*(p), int)); \
207 }
208
209extern int param_set_invbool(const char *val, struct kernel_param *kp);
210extern int param_get_invbool(char *buffer, struct kernel_param *kp);
211#define param_check_invbool(name, p) __param_check(name, p, bool)
212
213/* Comma-separated array: *nump is set to number they actually specified. */
214#define module_param_array_named(name, array, type, nump, perm) \
215 static const struct kparam_array __param_arr_##name \
216 = { ARRAY_SIZE(array), nump, param_set_##type, param_get_##type,\
217 sizeof(array[0]), array }; \
218 __module_param_call(MODULE_PARAM_PREFIX, name, \
219 param_array_set, param_array_get, \
220 .arr = &__param_arr_##name, \
221 __same_type(array[0], bool), perm); \
222 __MODULE_PARM_TYPE(name, "array of " #type)
223
224#define module_param_array(name, type, nump, perm) \
225 module_param_array_named(name, name, type, nump, perm)
226
227extern int param_array_set(const char *val, struct kernel_param *kp);
228extern int param_array_get(char *buffer, struct kernel_param *kp);
229
230extern int param_set_copystring(const char *val, struct kernel_param *kp);
231extern int param_get_string(char *buffer, struct kernel_param *kp);
232
233/* for exporting parameters in /sys/parameters */
234
235struct module;
236
237#if defined(CONFIG_SYSFS) && defined(CONFIG_MODULES)
238extern int module_param_sysfs_setup(struct module *mod,
239 struct kernel_param *kparam,
240 unsigned int num_params);
241
242extern void module_param_sysfs_remove(struct module *mod);
243#else
244static inline int module_param_sysfs_setup(struct module *mod,
245 struct kernel_param *kparam,
246 unsigned int num_params)
247{
248 return 0;
249}
250
251static inline void module_param_sysfs_remove(struct module *mod)
252{ }
253#endif
254
255#endif /* _LINUX_MODULE_PARAMS_H */