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