412 lines
14 KiB
C
412 lines
14 KiB
C
#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))
|
|
|
|
#define ___module_cat(a,b) __mod_ ## a ## b
|
|
#define __module_cat(a,b) ___module_cat(a,b)
|
|
#ifdef MODULE
|
|
#define __MODULE_INFO(tag, name, info) \
|
|
static const char __module_cat(name,__LINE__)[] \
|
|
__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 __module_cat(name,__LINE__) {}
|
|
#endif
|
|
#define __MODULE_PARM_TYPE(name, _type) \
|
|
__MODULE_INFO(parmtype, name##type, #name ":" _type)
|
|
|
|
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);
|
|
};
|
|
|
|
/* Flag bits for kernel_param.flags */
|
|
#define KPARAM_ISBOOL 2
|
|
|
|
struct kernel_param {
|
|
const char *name;
|
|
const struct kernel_param_ops *ops;
|
|
u16 perm;
|
|
u16 flags;
|
|
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, __same_type((arg), bool *), perm)
|
|
|
|
/* 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, isbool, perm) \
|
|
/* 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, isbool ? KPARAM_ISBOOL : 0, \
|
|
{ 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, \
|
|
__same_type(arg, bool *), \
|
|
(perm) + sizeof(__check_old_set_param(set))*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;
|
|
}
|
|
|
|
/**
|
|
* 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, __same_type(var, bool), perm)
|
|
#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, 0, perm); \
|
|
__MODULE_PARM_TYPE(name, "string")
|
|
|
|
/* Called on module insert or kernel boot */
|
|
extern int parse_args(const char *name,
|
|
char *args,
|
|
const struct kernel_param *params,
|
|
unsigned num,
|
|
int (*unknown)(char *param, char *val));
|
|
|
|
/* 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_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 *)
|
|
|
|
/* For historical reasons "bool" parameters can be (unsigned) "int". */
|
|
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) \
|
|
static inline void __check_##name(void) \
|
|
{ \
|
|
BUILD_BUG_ON(!__same_type((p), bool *) && \
|
|
!__same_type((p), unsigned int *) && \
|
|
!__same_type((p), int *)); \
|
|
}
|
|
|
|
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)
|
|
|
|
/**
|
|
* 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) \
|
|
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, \
|
|
__same_type(array[0], bool), perm); \
|
|
__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 */
|