diff options
Diffstat (limited to 'include/linux/moduleparam.h')
| -rw-r--r-- | include/linux/moduleparam.h | 184 |
1 files changed, 139 insertions, 45 deletions
diff --git a/include/linux/moduleparam.h b/include/linux/moduleparam.h index 1ee7b30dafec..915f32f7d888 100644 --- a/include/linux/moduleparam.h +++ b/include/linux/moduleparam.h @@ -1,3 +1,4 @@ +/* SPDX-License-Identifier: GPL-2.0 */ #ifndef _LINUX_MODULE_PARAMS_H #define _LINUX_MODULE_PARAMS_H /* (C) Copyright 2001, 2002 Rusty Russell IBM Corporation */ @@ -5,34 +6,40 @@ #include <linux/stringify.h> #include <linux/kernel.h> +/* + * The maximum module name length, including the NUL byte. + * Chosen so that structs with an unsigned long line up, specifically + * modversion_info. + */ +#define __MODULE_NAME_LEN (64 - sizeof(unsigned long)) + /* You can override this manually, but generally this should match the module name. */ #ifdef MODULE #define MODULE_PARAM_PREFIX /* empty */ +#define __MODULE_INFO_PREFIX /* empty */ #else #define MODULE_PARAM_PREFIX KBUILD_MODNAME "." +/* We cannot use MODULE_PARAM_PREFIX because some modules override it. */ +#define __MODULE_INFO_PREFIX KBUILD_MODNAME "." #endif -/* Chosen so that structs with an unsigned long line up. */ -#define MAX_PARAM_PREFIX_LEN (64 - sizeof(unsigned long)) +/* Generic info of form tag = "info" */ +#define MODULE_INFO(tag, info) \ + static_assert( \ + sizeof(info) - 1 == __builtin_strlen(info), \ + "MODULE_INFO(" #tag ", ...) contains embedded NUL byte"); \ + static const char __UNIQUE_ID(modinfo)[] \ + __used __section(".modinfo") __aligned(1) \ + = __MODULE_INFO_PREFIX __stringify(tag) "=" info -#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) + MODULE_INFO(parmtype, #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) + MODULE_INFO(parm, #_parm ":" desc) struct kernel_param; @@ -101,15 +108,15 @@ struct kparam_array /** * module_param - typesafe helper for a module/cmdline parameter - * @value: the variable to alter, and exposed parameter name. + * @name: 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 + * @name 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 + * @perm is 0 if 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 kernel_param_lock() around * accesses (esp. charp, which can be kfreed when it changes). @@ -119,7 +126,7 @@ struct kparam_array * you can create your own by defining those variables. * * Standard types are: - * byte, short, ushort, int, uint, long, ulong + * byte, hexint, 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). @@ -129,6 +136,9 @@ struct kparam_array /** * module_param_unsafe - same as module_param but taints kernel + * @name: the variable to alter, and exposed parameter name. + * @type: the type of the parameter + * @perm: visibility in sysfs. */ #define module_param_unsafe(name, type, perm) \ module_param_named_unsafe(name, name, type, perm) @@ -151,6 +161,10 @@ struct kparam_array /** * module_param_named_unsafe - same as module_param_named but taints kernel + * @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. */ #define module_param_named_unsafe(name, value, type, perm) \ param_check_##type(name, &(value)); \ @@ -161,6 +175,7 @@ struct kparam_array * 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. + * @arg: args for @ops * @perm: visibility in sysfs. * * The ops can have NULL set or get functions. @@ -172,36 +187,96 @@ struct kparam_array __module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, -1, \ KERNEL_PARAM_FL_UNSAFE) +#define __level_param_cb(name, ops, arg, perm, level) \ + __module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, level, 0) /** - * <level>_param_cb - general callback for a module/cmdline parameter - * to be evaluated before certain initcall level + * core_param_cb - general callback for a module/cmdline parameter + * to be evaluated before core initcall level * @name: a valid C identifier which is the parameter name. * @ops: the set & get operations for this parameter. + * @arg: args for @ops * @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, 0) - #define core_param_cb(name, ops, arg, perm) \ __level_param_cb(name, ops, arg, perm, 1) +/** + * postcore_param_cb - general callback for a module/cmdline parameter + * to be evaluated before postcore initcall level + * @name: a valid C identifier which is the parameter name. + * @ops: the set & get operations for this parameter. + * @arg: args for @ops + * @perm: visibility in sysfs. + * + * The ops can have NULL set or get functions. + */ #define postcore_param_cb(name, ops, arg, perm) \ __level_param_cb(name, ops, arg, perm, 2) +/** + * arch_param_cb - general callback for a module/cmdline parameter + * to be evaluated before arch initcall level + * @name: a valid C identifier which is the parameter name. + * @ops: the set & get operations for this parameter. + * @arg: args for @ops + * @perm: visibility in sysfs. + * + * The ops can have NULL set or get functions. + */ #define arch_param_cb(name, ops, arg, perm) \ __level_param_cb(name, ops, arg, perm, 3) +/** + * subsys_param_cb - general callback for a module/cmdline parameter + * to be evaluated before subsys initcall level + * @name: a valid C identifier which is the parameter name. + * @ops: the set & get operations for this parameter. + * @arg: args for @ops + * @perm: visibility in sysfs. + * + * The ops can have NULL set or get functions. + */ #define subsys_param_cb(name, ops, arg, perm) \ __level_param_cb(name, ops, arg, perm, 4) +/** + * fs_param_cb - general callback for a module/cmdline parameter + * to be evaluated before fs initcall level + * @name: a valid C identifier which is the parameter name. + * @ops: the set & get operations for this parameter. + * @arg: args for @ops + * @perm: visibility in sysfs. + * + * The ops can have NULL set or get functions. + */ #define fs_param_cb(name, ops, arg, perm) \ __level_param_cb(name, ops, arg, perm, 5) +/** + * device_param_cb - general callback for a module/cmdline parameter + * to be evaluated before device initcall level + * @name: a valid C identifier which is the parameter name. + * @ops: the set & get operations for this parameter. + * @arg: args for @ops + * @perm: visibility in sysfs. + * + * The ops can have NULL set or get functions. + */ #define device_param_cb(name, ops, arg, perm) \ __level_param_cb(name, ops, arg, perm, 6) +/** + * late_param_cb - general callback for a module/cmdline parameter + * to be evaluated before late initcall level + * @name: a valid C identifier which is the parameter name. + * @ops: the set & get operations for this parameter. + * @arg: args for @ops + * @perm: visibility in sysfs. + * + * The ops can have NULL set or get functions. + */ #define late_param_cb(name, ops, arg, perm) \ __level_param_cb(name, ops, arg, perm, 7) @@ -209,37 +284,32 @@ struct kparam_array 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) +#if defined(CONFIG_ALPHA) || defined(CONFIG_PPC64) #define __moduleparam_const #else #define __moduleparam_const const #endif -/* This is the fundamental function for registering boot/module - parameters. */ +/* This is the fundamental function for registering boot/module parameters. */ #define __module_param_call(prefix, name, ops, arg, perm, level, flags) \ - /* Default value instead of permissions? */ \ + static_assert(sizeof(""prefix) - 1 <= __MODULE_NAME_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 *)))) \ + __used __section("__param") \ + __aligned(__alignof__(struct kernel_param)) \ = { __param_str_##name, THIS_MODULE, ops, \ VERIFY_OCTAL_PERMISSIONS(perm), level, flags, { arg } } -/* Obsolete - use module_param_cb() */ -#define module_param_call(name, set, get, arg, perm) \ - static const struct kernel_param_ops __param_ops_##name = \ - { .flags = 0, (void *)set, (void *)get }; \ +/* + * Useful for describing a set/get pair used only once (i.e. for this + * parameter). For repeated set/get pairs (i.e. the same struct + * kernel_param_ops), use module_param_cb() instead. + */ +#define module_param_call(name, _set, _get, arg, perm) \ + static const struct kernel_param_ops __param_ops_##name = \ + { .flags = 0, .set = _set, .get = _get }; \ __module_param_call(MODULE_PARAM_PREFIX, \ - name, &__param_ops_##name, arg, \ - (perm) + sizeof(__check_old_set_param(set))*0, -1, 0) - -/* 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; -} + name, &__param_ops_##name, arg, perm, -1, 0) #ifdef CONFIG_SYSFS extern void kernel_param_lock(struct module *mod); @@ -272,12 +342,29 @@ static inline void kernel_param_unlock(struct module *mod) /** * core_param_unsafe - same as core_param but taints kernel + * @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 */ #define core_param_unsafe(name, var, type, perm) \ param_check_##type(name, &(var)); \ __module_param_call("", name, ¶m_ops_##type, &var, perm, \ -1, KERNEL_PARAM_FL_UNSAFE) +/** + * __core_param_cb - similar like core_param, with a set/get ops instead of type. + * @name: the name of the cmdline and sysfs parameter (often the same as var) + * @var: the variable + * @ops: the set & get operations for this parameter. + * @perm: visibility in sysfs + * + * Ideally this should be called 'core_param_cb', but the name has been + * used for module core parameter, so add the '__' prefix + */ +#define __core_param_cb(name, ops, arg, perm) \ + __module_param_call("", name, ops, arg, perm, -1, 0) + #endif /* !MODULE */ /** @@ -318,6 +405,8 @@ extern bool parameq(const char *name1, const char *name2); */ extern bool parameqn(const char *name1, const char *name2, size_t n); +typedef int (*parse_unknown_fn)(char *param, char *val, const char *doing, void *arg); + /* Called on module insert or kernel boot */ extern char *parse_args(const char *name, char *args, @@ -325,9 +414,7 @@ extern char *parse_args(const char *name, unsigned num, s16 level_min, s16 level_max, - void *arg, - int (*unknown)(char *param, char *val, - const char *doing, void *arg)); + void *arg, parse_unknown_fn unknown); /* Called by module remove. */ #ifdef CONFIG_SYSFS @@ -368,6 +455,8 @@ extern int param_get_int(char *buffer, const struct kernel_param *kp); extern const 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); +int param_set_uint_minmax(const char *val, const struct kernel_param *kp, + unsigned int min, unsigned int max); #define param_check_uint(name, p) __param_check(name, p, unsigned int) extern const struct kernel_param_ops param_ops_long; @@ -385,6 +474,11 @@ 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 const struct kernel_param_ops param_ops_hexint; +extern int param_set_hexint(const char *val, const struct kernel_param *kp); +extern int param_get_hexint(char *buffer, const struct kernel_param *kp); +#define param_check_hexint(name, p) param_check_uint(name, p) + extern const 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); |
