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