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 __stringify(KBUILD_MODNAME) "."
  14 #endif
  15
  16 struct kernel_param;
  17
  18 /* Returns 0, or -errno.  arg is in kp->arg. */
  19 typedef int (*param_set_fn)(const char *val, struct kernel_param *kp);
  20 /* Returns length written or -errno.  Buffer is 4k (ie. be short!) */
  21 typedef int (*param_get_fn)(char *buffer, struct kernel_param *kp);
  22
  23 struct kernel_param {
  24         const char *name;
  25         unsigned int perm;
  26         param_set_fn set;
  27         param_get_fn get;
  28         void *arg;
  29 };
  30
  31 /* Special one for strings we want to copy into */
  32 struct kparam_string {
  33         unsigned int maxlen;
  34         char *string;
  35 };
  36
  37 /* Special one for arrays */
  38 struct kparam_array
  39 {
  40         unsigned int max;
  41         unsigned int *num;
  42         param_set_fn set;
  43         param_get_fn get;
  44         unsigned int elemsize;
  45         void *elem;
  46 };
  47
  48 /* This is the fundamental function for registering boot/module
  49    parameters.  perm sets the visibility in driverfs: 000 means it's
  50    not there, read bits mean it's readable, write bits mean it's
  51    writable. */
  52 #define __module_param_call(prefix, name, set, get, arg, perm)          \
  53         static char __param_str_##name[] __initdata = prefix #name;     \
  54         static struct kernel_param const __param_##name                 \
  55         __attribute_used__                                              \
  56     __attribute__ ((unused,__section__ ("__param"),aligned(sizeof(void *)))) \
  57         = { __param_str_##name, perm, set, get, arg }
  58
  59 #define module_param_call(name, set, get, arg, perm)                          \
  60         __module_param_call(MODULE_PARAM_PREFIX, name, set, get, arg, perm)
  61
  62 /* Helper functions: type is byte, short, ushort, int, uint, long,
  63    ulong, charp, bool or invbool, or XXX if you define param_get_XXX,
  64    param_set_XXX and param_check_XXX. */
  65 #define module_param_named(name, value, type, perm)                        \
  66         param_check_##type(name, &(value));                                \
  67         module_param_call(name, param_set_##type, param_get_##type, &value, perm)
  68
  69 #define module_param(name, type, perm)                          \
  70         module_param_named(name, name, type, perm)
  71
  72 /* Actually copy string: maxlen param is usually sizeof(string). */
  73 #define module_param_string(name, string, len, perm)                    \
  74         static struct kparam_string __param_string_##name __initdata    \
  75                 = { len, string };                                      \
  76         module_param_call(name, param_set_copystring, param_get_charp,  \
  77                    &__param_string_##name, perm)
  78
  79 /* Called on module insert or kernel boot */
  80 extern int parse_args(const char *name,
  81                       char *args,
  82                       struct kernel_param *params,
  83                       unsigned num,
  84                       int (*unknown)(char *param, char *val));
  85
  86 /* All the helper functions */
  87 /* The macros to do compile-time type checking stolen from Jakub
  88    Jelinek, who IIRC came up with this idea for the 2.4 module init code. */
  89 #define __param_check(name, p, type) \
  90         static inline type *__check_##name(void) { return(p); }
  91
  92 extern int param_set_short(const char *val, struct kernel_param *kp);
  93 extern int param_get_short(char *buffer, struct kernel_param *kp);
  94 #define param_check_short(name, p) __param_check(name, p, short)
  95
  96 extern int param_set_ushort(const char *val, struct kernel_param *kp);
  97 extern int param_get_ushort(char *buffer, struct kernel_param *kp);
  98 #define param_check_ushort(name, p) __param_check(name, p, unsigned short)
  99
 100 extern int param_set_int(const char *val, struct kernel_param *kp);
 101 extern int param_get_int(char *buffer, struct kernel_param *kp);
 102 #define param_check_int(name, p) __param_check(name, p, int)
 103
 104 extern int param_set_uint(const char *val, struct kernel_param *kp);
 105 extern int param_get_uint(char *buffer, struct kernel_param *kp);
 106 #define param_check_uint(name, p) __param_check(name, p, unsigned int)
 107
 108 extern int param_set_long(const char *val, struct kernel_param *kp);
 109 extern int param_get_long(char *buffer, struct kernel_param *kp);
 110 #define param_check_long(name, p) __param_check(name, p, long)
 111
 112 extern int param_set_ulong(const char *val, struct kernel_param *kp);
 113 extern int param_get_ulong(char *buffer, struct kernel_param *kp);
 114 #define param_check_ulong(name, p) __param_check(name, p, unsigned long)
 115
 116 extern int param_set_charp(const char *val, struct kernel_param *kp);
 117 extern int param_get_charp(char *buffer, struct kernel_param *kp);
 118 #define param_check_charp(name, p) __param_check(name, p, char *)
 119
 120 extern int param_set_bool(const char *val, struct kernel_param *kp);
 121 extern int param_get_bool(char *buffer, struct kernel_param *kp);
 122 #define param_check_bool(name, p) __param_check(name, p, int)
 123
 124 extern int param_set_invbool(const char *val, struct kernel_param *kp);
 125 extern int param_get_invbool(char *buffer, struct kernel_param *kp);
 126 #define param_check_invbool(name, p) __param_check(name, p, int)
 127
 128 /* Comma-separated array: num is set to number they actually specified. */
 129 #define module_param_array_named(name, array, type, num, perm)          \
 130         static struct kparam_array __param_arr_##name                   \
 131         = { ARRAY_SIZE(array), &num, param_set_##type, param_get_##type,\
 132             sizeof(array[0]), array };                                  \
 133         module_param_call(name, param_array_set, param_array_get,       \
 134                           &__param_arr_##name, perm)
 135
 136 #define module_param_array(name, type, num, perm)               \
 137         module_param_array_named(name, name, type, num, perm)
 138
 139 extern int param_array_set(const char *val, struct kernel_param *kp);
 140 extern int param_array_get(char *buffer, struct kernel_param *kp);
 141
 142 extern int param_set_copystring(const char *val, struct kernel_param *kp);
 143
 144 int param_array(const char *name,
 145                 const char *val,
 146                 unsigned int min, unsigned int max,
 147                 void *elem, int elemsize,
 148                 int (*set)(const char *, struct kernel_param *kp),
 149                 int *num);
 150 #endif /* _LINUX_MODULE_PARAM_TYPES_H */