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