Edit File: moduleparam.h
#ifndef _LINUX_MODULE_PARAMS_H #define _LINUX_MODULE_PARAMS_H /* (C) Copyright 2001, 2002 Rusty Russell IBM Corporation */ #include <linux/init.h> #include <linux/stringify.h> #include <linux/kernel.h> /* You can override this manually, but generally this should match the module name. */ #ifdef MODULE #define MODULE_PARAM_PREFIX /* empty */ #else #define MODULE_PARAM_PREFIX KBUILD_MODNAME "." #endif /* Chosen so that structs with an unsigned long line up. */ #define MAX_PARAM_PREFIX_LEN (64 - sizeof(unsigned long)) #ifdef MODULE #define __MODULE_INFO(tag, name, info) \ static const char __UNIQUE_ID(name)[] \ __used __attribute__((section(".modinfo"), unused, aligned(1))) \ = __stringify(tag) "=" info #else /* !MODULE */ /* This struct is here for syntactic coherency, it is not used */ #define __MODULE_INFO(tag, name, info) \ struct __UNIQUE_ID(name) {} #endif #define __MODULE_PARM_TYPE(name, _type) \ __MODULE_INFO(parmtype, name##type, #name ":" _type) /* One for each parameter, describing how to use it. Some files do multiple of these per line, so can't just use MODULE_INFO. */ #define MODULE_PARM_DESC(_parm, desc) \ __MODULE_INFO(parm, _parm, #_parm ":" desc) struct kernel_param; struct kernel_param_ops { /* Returns 0, or -errno. arg is in kp->arg. */ int (*set)(const char *val, const struct kernel_param *kp); /* Returns length written or -errno. Buffer is 4k (ie. be short!) */ int (*get)(char *buffer, const struct kernel_param *kp); /* Optional function to free kp->arg when module unloaded. */ void (*free)(void *arg); }; struct kernel_param { const char *name; const struct kernel_param_ops *ops; u16 perm; s16 level; union { void *arg; const struct kparam_string *str; const struct kparam_array *arr; }; }; /* Special one for strings we want to copy into */ struct kparam_string { unsigned int maxlen; char *string; }; /* Special one for arrays */ struct kparam_array { unsigned int max; unsigned int elemsize; unsigned int *num; const struct kernel_param_ops *ops; void *elem; }; /** * module_param - typesafe helper for a module/cmdline parameter * @value: the variable to alter, and exposed parameter name. * @type: the type of the parameter * @perm: visibility in sysfs. * * @value becomes the module parameter, or (prefixed by KBUILD_MODNAME and a * ".") the kernel commandline parameter. Note that - is changed to _, so * the user can use "foo-bar=1" even for variable "foo_bar". * * @perm is 0 if the the variable is not to appear in sysfs, or 0444 * for world-readable, 0644 for root-writable, etc. Note that if it * is writable, you may need to use kparam_block_sysfs_write() around * accesses (esp. charp, which can be kfreed when it changes). * * The @type is simply pasted to refer to a param_ops_##type and a * param_check_##type: for convenience many standard types are provided but * you can create your own by defining those variables. * * Standard types are: * byte, short, ushort, int, uint, long, ulong * charp: a character pointer * bool: a bool, values 0/1, y/n, Y/N. * invbool: the above, only sense-reversed (N = true). */ #define module_param(name, type, perm) \ module_param_named(name, name, type, perm) /** * module_param_named - typesafe helper for a renamed module/cmdline parameter * @name: a valid C identifier which is the parameter name. * @value: the actual lvalue to alter. * @type: the type of the parameter * @perm: visibility in sysfs. * * Usually it's a good idea to have variable names and user-exposed names the * same, but that's harder if the variable must be non-static or is inside a * structure. This allows exposure under a different name. */ #define module_param_named(name, value, type, perm) \ param_check_##type(name, &(value)); \ module_param_cb(name, ¶m_ops_##type, &value, perm); \ __MODULE_PARM_TYPE(name, #type) /** * module_param_cb - general callback for a module/cmdline parameter * @name: a valid C identifier which is the parameter name. * @ops: the set & get operations for this parameter. * @perm: visibility in sysfs. * * The ops can have NULL set or get functions. */ #define module_param_cb(name, ops, arg, perm) \ __module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, -1) /** * <level>_param_cb - general callback for a module/cmdline parameter * to be evaluated before certain initcall level * @name: a valid C identifier which is the parameter name. * @ops: the set & get operations for this parameter. * @perm: visibility in sysfs. * * The ops can have NULL set or get functions. */ #define __level_param_cb(name, ops, arg, perm, level) \ __module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, level) #define core_param_cb(name, ops, arg, perm) \ __level_param_cb(name, ops, arg, perm, 1) #define postcore_param_cb(name, ops, arg, perm) \ __level_param_cb(name, ops, arg, perm, 2) #define arch_param_cb(name, ops, arg, perm) \ __level_param_cb(name, ops, arg, perm, 3) #define subsys_param_cb(name, ops, arg, perm) \ __level_param_cb(name, ops, arg, perm, 4) #define fs_param_cb(name, ops, arg, perm) \ __level_param_cb(name, ops, arg, perm, 5) #define device_param_cb(name, ops, arg, perm) \ __level_param_cb(name, ops, arg, perm, 6) #define late_param_cb(name, ops, arg, perm) \ __level_param_cb(name, ops, arg, perm, 7) /* On alpha, ia64 and ppc64 relocations to global data cannot go into read-only sections (which is part of respective UNIX ABI on these platforms). So 'const' makes no sense and even causes compile failures with some compilers. */ #if defined(CONFIG_ALPHA) || defined(CONFIG_IA64) || defined(CONFIG_PPC64) #define __moduleparam_const #else #define __moduleparam_const const #endif /* This is the fundamental function for registering boot/module parameters. */ #define __module_param_call(prefix, name, ops, arg, perm, level) \ /* Default value instead of permissions? */ \ static int __param_perm_check_##name __attribute__((unused)) = \ BUILD_BUG_ON_ZERO((perm) < 0 || (perm) > 0777 || ((perm) & 2)) \ + BUILD_BUG_ON_ZERO(sizeof(""prefix) > MAX_PARAM_PREFIX_LEN); \ static const char __param_str_##name[] = prefix #name; \ static struct kernel_param __moduleparam_const __param_##name \ __used \ __attribute__ ((unused,__section__ ("__param"),aligned(sizeof(void *)))) \ = { __param_str_##name, ops, perm, level, { arg } } /* Obsolete - use module_param_cb() */ #define module_param_call(name, set, get, arg, perm) \ static struct kernel_param_ops __param_ops_##name = \ { (void *)set, (void *)get }; \ __module_param_call(MODULE_PARAM_PREFIX, \ name, &__param_ops_##name, arg, \ (perm) + sizeof(__check_old_set_param(set))*0, -1) /* We don't get oldget: it's often a new-style param_get_uint, etc. */ static inline int __check_old_set_param(int (*oldset)(const char *, struct kernel_param *)) { return 0; } /** * kparam_block_sysfs_write - make sure a parameter isn't written via sysfs. * @name: the name of the parameter * * There's no point blocking write on a paramter that isn't writable via sysfs! */ #define kparam_block_sysfs_write(name) \ do { \ BUG_ON(!(__param_##name.perm & 0222)); \ __kernel_param_lock(); \ } while (0) /** * kparam_unblock_sysfs_write - allows sysfs to write to a parameter again. * @name: the name of the parameter */ #define kparam_unblock_sysfs_write(name) \ do { \ BUG_ON(!(__param_##name.perm & 0222)); \ __kernel_param_unlock(); \ } while (0) /** * kparam_block_sysfs_read - make sure a parameter isn't read via sysfs. * @name: the name of the parameter * * This also blocks sysfs writes. */ #define kparam_block_sysfs_read(name) \ do { \ BUG_ON(!(__param_##name.perm & 0444)); \ __kernel_param_lock(); \ } while (0) /** * kparam_unblock_sysfs_read - allows sysfs to read a parameter again. * @name: the name of the parameter */ #define kparam_unblock_sysfs_read(name) \ do { \ BUG_ON(!(__param_##name.perm & 0444)); \ __kernel_param_unlock(); \ } while (0) #ifdef CONFIG_SYSFS extern void __kernel_param_lock(void); extern void __kernel_param_unlock(void); #else static inline void __kernel_param_lock(void) { } static inline void __kernel_param_unlock(void) { } #endif #ifndef MODULE /** * core_param - define a historical core kernel parameter. * @name: the name of the cmdline and sysfs parameter (often the same as var) * @var: the variable * @type: the type of the parameter * @perm: visibility in sysfs * * core_param is just like module_param(), but cannot be modular and * doesn't add a prefix (such as "printk."). This is for compatibility * with __setup(), and it makes sense as truly core parameters aren't * tied to the particular file they're in. */ #define core_param(name, var, type, perm) \ param_check_##type(name, &(var)); \ __module_param_call("", name, ¶m_ops_##type, &var, perm, -1) #endif /* !MODULE */ /** * module_param_string - a char array parameter * @name: the name of the parameter * @string: the string variable * @len: the maximum length of the string, incl. terminator * @perm: visibility in sysfs. * * This actually copies the string when it's set (unlike type charp). * @len is usually just sizeof(string). */ #define module_param_string(name, string, len, perm) \ static const struct kparam_string __param_string_##name \ = { len, string }; \ __module_param_call(MODULE_PARAM_PREFIX, name, \ ¶m_ops_string, \ .str = &__param_string_##name, perm, -1); \ __MODULE_PARM_TYPE(name, "string") /** * parameq - checks if two parameter names match * @name1: parameter name 1 * @name2: parameter name 2 * * Returns true if the two parameter names are equal. * Dashes (-) are considered equal to underscores (_). */ extern bool parameq(const char *name1, const char *name2); /** * parameqn - checks if two parameter names match * @name1: parameter name 1 * @name2: parameter name 2 * @n: the length to compare * * Similar to parameq(), except it compares @n characters. */ extern bool parameqn(const char *name1, const char *name2, size_t n); /* Called on module insert or kernel boot */ extern int parse_args(const char *name, char *args, const struct kernel_param *params, unsigned num, s16 level_min, s16 level_max, int (*unknown)(char *param, char *val, const char *doing)); /* Called by module remove. */ #ifdef CONFIG_SYSFS extern void destroy_params(const struct kernel_param *params, unsigned num); #else static inline void destroy_params(const struct kernel_param *params, unsigned num) { } #endif /* !CONFIG_SYSFS */ /* All the helper functions */ /* The macros to do compile-time type checking stolen from Jakub Jelinek, who IIRC came up with this idea for the 2.4 module init code. */ #define __param_check(name, p, type) \ static inline type *__check_##name(void) { return(p); } extern struct kernel_param_ops param_ops_byte; extern int param_set_byte(const char *val, const struct kernel_param *kp); extern int param_get_byte(char *buffer, const struct kernel_param *kp); #define param_check_byte(name, p) __param_check(name, p, unsigned char) extern struct kernel_param_ops param_ops_short; extern int param_set_short(const char *val, const struct kernel_param *kp); extern int param_get_short(char *buffer, const struct kernel_param *kp); #define param_check_short(name, p) __param_check(name, p, short) extern struct kernel_param_ops param_ops_ushort; extern int param_set_ushort(const char *val, const struct kernel_param *kp); extern int param_get_ushort(char *buffer, const struct kernel_param *kp); #define param_check_ushort(name, p) __param_check(name, p, unsigned short) extern struct kernel_param_ops param_ops_int; extern int param_set_int(const char *val, const struct kernel_param *kp); extern int param_get_int(char *buffer, const struct kernel_param *kp); #define param_check_int(name, p) __param_check(name, p, int) extern struct kernel_param_ops param_ops_uint; extern int param_set_uint(const char *val, const struct kernel_param *kp); extern int param_get_uint(char *buffer, const struct kernel_param *kp); #define param_check_uint(name, p) __param_check(name, p, unsigned int) extern struct kernel_param_ops param_ops_long; extern int param_set_long(const char *val, const struct kernel_param *kp); extern int param_get_long(char *buffer, const struct kernel_param *kp); #define param_check_long(name, p) __param_check(name, p, long) extern struct kernel_param_ops param_ops_ulong; extern int param_set_ulong(const char *val, const struct kernel_param *kp); extern int param_get_ulong(char *buffer, const struct kernel_param *kp); #define param_check_ulong(name, p) __param_check(name, p, unsigned long) extern struct kernel_param_ops param_ops_ullong; extern int param_set_ullong(const char *val, const struct kernel_param *kp); extern int param_get_ullong(char *buffer, const struct kernel_param *kp); #define param_check_ullong(name, p) __param_check(name, p, unsigned long long) extern struct kernel_param_ops param_ops_charp; extern int param_set_charp(const char *val, const struct kernel_param *kp); extern int param_get_charp(char *buffer, const struct kernel_param *kp); #define param_check_charp(name, p) __param_check(name, p, char *) /* We used to allow int as well as bool. We're taking that away! */ extern struct kernel_param_ops param_ops_bool; extern int param_set_bool(const char *val, const struct kernel_param *kp); extern int param_get_bool(char *buffer, const struct kernel_param *kp); #define param_check_bool(name, p) __param_check(name, p, bool) extern struct kernel_param_ops param_ops_invbool; extern int param_set_invbool(const char *val, const struct kernel_param *kp); extern int param_get_invbool(char *buffer, const struct kernel_param *kp); #define param_check_invbool(name, p) __param_check(name, p, bool) /* An int, which can only be set like a bool (though it shows as an int). */ extern struct kernel_param_ops param_ops_bint; extern int param_set_bint(const char *val, const struct kernel_param *kp); #define param_get_bint param_get_int #define param_check_bint param_check_int /** * module_param_array - a parameter which is an array of some type * @name: the name of the array variable * @type: the type, as per module_param() * @nump: optional pointer filled in with the number written * @perm: visibility in sysfs * * Input and output are as comma-separated values. Commas inside values * don't work properly (eg. an array of charp). * * ARRAY_SIZE(@name) is used to determine the number of elements in the * array, so the definition must be visible. */ #define module_param_array(name, type, nump, perm) \ module_param_array_named(name, name, type, nump, perm) /** * module_param_array_named - renamed parameter which is an array of some type * @name: a valid C identifier which is the parameter name * @array: the name of the array variable * @type: the type, as per module_param() * @nump: optional pointer filled in with the number written * @perm: visibility in sysfs * * This exposes a different name than the actual variable name. See * module_param_named() for why this might be necessary. */ #define module_param_array_named(name, array, type, nump, perm) \ param_check_##type(name, &(array)[0]); \ static const struct kparam_array __param_arr_##name \ = { .max = ARRAY_SIZE(array), .num = nump, \ .ops = ¶m_ops_##type, \ .elemsize = sizeof(array[0]), .elem = array }; \ __module_param_call(MODULE_PARAM_PREFIX, name, \ ¶m_array_ops, \ .arr = &__param_arr_##name, \ perm, -1); \ __MODULE_PARM_TYPE(name, "array of " #type) extern struct kernel_param_ops param_array_ops; extern struct kernel_param_ops param_ops_string; extern int param_set_copystring(const char *val, const struct kernel_param *); extern int param_get_string(char *buffer, const struct kernel_param *kp); /* for exporting parameters in /sys/parameters */ struct module; #if defined(CONFIG_SYSFS) && defined(CONFIG_MODULES) extern int module_param_sysfs_setup(struct module *mod, const struct kernel_param *kparam, unsigned int num_params); extern void module_param_sysfs_remove(struct module *mod); #else static inline int module_param_sysfs_setup(struct module *mod, const struct kernel_param *kparam, unsigned int num_params) { return 0; } static inline void module_param_sysfs_remove(struct module *mod) { } #endif #endif /* _LINUX_MODULE_PARAMS_H */