LXR linux/include/linux/moduleparam.h

   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#ifdef MODULE
  17#define ___module_cat(a,b) __mod_ ## a ## b
  18#define __module_cat(a,b) ___module_cat(a,b)
  19#define __MODULE_INFO(tag, name, info)                                    \
  20static const char __module_cat(name,__LINE__)[]                           \
  21  __attribute_used__                                                      \
  22  __attribute__((section(".modinfo"),unused)) = __stringify(tag) "=" info
  23#else  /* !MODULE */
  24#define __MODULE_INFO(tag, name, info)
  25#endif
  26#define __MODULE_PARM_TYPE(name, _type)                                   \
  27  __MODULE_INFO(parmtype, name##type, #name ":" _type)
  28
  29struct kernel_param;
  30
  31/* Returns 0, or -errno.  arg is in kp->arg. */
  32typedef int (*param_set_fn)(const char *val, struct kernel_param *kp);
  33/* Returns length written or -errno.  Buffer is 4k (ie. be short!) */
  34typedef int (*param_get_fn)(char *buffer, struct kernel_param *kp);
  35
  36struct kernel_param {
  37        const char *name;
  38        unsigned int perm;
  39        param_set_fn set;
  40        param_get_fn get;
  41        void *arg;
  42};
  43
  44/* Special one for strings we want to copy into */
  45struct kparam_string {
  46        unsigned int maxlen;
  47        char *string;
  48};
  49
  50/* Special one for arrays */
  51struct kparam_array
  52{
  53        unsigned int max;
  54        unsigned int *num;
  55        param_set_fn set;
  56        param_get_fn get;
  57        unsigned int elemsize;
  58        void *elem;
  59};
  60
  61/* This is the fundamental function for registering boot/module
  62   parameters.  perm sets the visibility in driverfs: 000 means it's
  63   not there, read bits mean it's readable, write bits mean it's
  64   writable. */
  65#define __module_param_call(prefix, name, set, get, arg, perm)          \
  66        static char __param_str_##name[] = prefix #name;                \
  67        static struct kernel_param const __param_##name                 \
  68        __attribute_used__                                              \
  69    __attribute__ ((unused,__section__ ("__param"),aligned(sizeof(void *)))) \
  70        = { __param_str_##name, perm, set, get, arg }
  71
  72#define module_param_call(name, set, get, arg, perm)                          \
  73        __module_param_call(MODULE_PARAM_PREFIX, name, set, get, arg, perm)
  74
  75/* Helper functions: type is byte, short, ushort, int, uint, long,
  76   ulong, charp, bool or invbool, or XXX if you define param_get_XXX,
  77   param_set_XXX and param_check_XXX. */
  78#define module_param_named(name, value, type, perm)                        \
  79        param_check_##type(name, &(value));                                \
  80        module_param_call(name, param_set_##type, param_get_##type, &value, perm); \
  81        __MODULE_PARM_TYPE(name, #type)
  82
  83#define module_param(name, type, perm)                          \
  84        module_param_named(name, name, type, perm)
  85
  86/* Actually copy string: maxlen param is usually sizeof(string). */
  87#define module_param_string(name, string, len, perm)                    \
  88        static struct kparam_string __param_string_##name               \
  89                = { len, string };                                      \
  90        module_param_call(name, param_set_copystring, param_get_string, \
  91                   &__param_string_##name, perm);                       \
  92        __MODULE_PARM_TYPE(name, "string")
  93
  94/* Called on module insert or kernel boot */
  95extern int parse_args(const char *name,
  96                      char *args,
  97                      struct kernel_param *params,
  98                      unsigned num,
  99                      int (*unknown)(char *param, char *val));
 100
 101/* All the helper functions */
 102/* The macros to do compile-time type checking stolen from Jakub
 103   Jelinek, who IIRC came up with this idea for the 2.4 module init code. */
 104#define __param_check(name, p, type) \
 105        static inline type *__check_##name(void) { return(p); }
 106
 107extern int param_set_byte(const char *val, struct kernel_param *kp);
 108extern int param_get_byte(char *buffer, struct kernel_param *kp);
 109#define param_check_byte(name, p) __param_check(name, p, unsigned char)
 110
 111extern int param_set_short(const char *val, struct kernel_param *kp);
 112extern int param_get_short(char *buffer, struct kernel_param *kp);
 113#define param_check_short(name, p) __param_check(name, p, short)
 114
 115extern int param_set_ushort(const char *val, struct kernel_param *kp);
 116extern int param_get_ushort(char *buffer, struct kernel_param *kp);
 117#define param_check_ushort(name, p) __param_check(name, p, unsigned short)
 118
 119extern int param_set_int(const char *val, struct kernel_param *kp);
 120extern int param_get_int(char *buffer, struct kernel_param *kp);
 121#define param_check_int(name, p) __param_check(name, p, int)
 122
 123extern int param_set_uint(const char *val, struct kernel_param *kp);
 124extern int param_get_uint(char *buffer, struct kernel_param *kp);
 125#define param_check_uint(name, p) __param_check(name, p, unsigned int)
 126
 127extern int param_set_long(const char *val, struct kernel_param *kp);
 128extern int param_get_long(char *buffer, struct kernel_param *kp);
 129#define param_check_long(name, p) __param_check(name, p, long)
 130
 131extern int param_set_ulong(const char *val, struct kernel_param *kp);
 132extern int param_get_ulong(char *buffer, struct kernel_param *kp);
 133#define param_check_ulong(name, p) __param_check(name, p, unsigned long)
 134
 135extern int param_set_charp(const char *val, struct kernel_param *kp);
 136extern int param_get_charp(char *buffer, struct kernel_param *kp);
 137#define param_check_charp(name, p) __param_check(name, p, char *)
 138
 139extern int param_set_bool(const char *val, struct kernel_param *kp);
 140extern int param_get_bool(char *buffer, struct kernel_param *kp);
 141#define param_check_bool(name, p) __param_check(name, p, int)
 142
 143extern int param_set_invbool(const char *val, struct kernel_param *kp);
 144extern int param_get_invbool(char *buffer, struct kernel_param *kp);
 145#define param_check_invbool(name, p) __param_check(name, p, int)
 146
 147/* Comma-separated array: *nump is set to number they actually specified. */
 148#define module_param_array_named(name, array, type, nump, perm)         \
 149        static struct kparam_array __param_arr_##name                   \
 150        = { ARRAY_SIZE(array), nump, param_set_##type, param_get_##type,\
 151            sizeof(array[0]), array };                                  \
 152        module_param_call(name, param_array_set, param_array_get,       \
 153                          &__param_arr_##name, perm);                   \
 154        __MODULE_PARM_TYPE(name, "array of " #type)
 155
 156#define module_param_array(name, type, nump, perm)              \
 157        module_param_array_named(name, name, type, nump, perm)
 158
 159extern int param_array_set(const char *val, struct kernel_param *kp);
 160extern int param_array_get(char *buffer, struct kernel_param *kp);
 161
 162extern int param_set_copystring(const char *val, struct kernel_param *kp);
 163extern int param_get_string(char *buffer, struct kernel_param *kp);
 164
 165/* for exporting parameters in /sys/parameters */
 166
 167struct module;
 168
 169extern int module_param_sysfs_setup(struct module *mod,
 170                                    struct kernel_param *kparam,
 171                                    unsigned int num_params);
 172
 173extern void module_param_sysfs_remove(struct module *mod);
 174
 175#endif /* _LINUX_MODULE_PARAMS_H */
 176