linux-hardened/include/linux/moduleparam.h
Rusty Russell 9bbb9e5a33 param: use ops in struct kernel_param, rather than get and set fns directly
This is more kernel-ish, saves some space, and also allows us to
expand the ops without breaking all the callers who are happy for the
new members to be NULL.

The few places which defined their own param types are changed to the
new scheme (more which crept in recently fixed in following patches).

Since we're touching them anyway, we change get() and set() to take a
const struct kernel_param (which they really are).  This causes some
harmless warnings until we fix them (in following patches).

To reduce churn, module_param_call creates the ops struct so the callers
don't have to change (and casts the functions to reduce warnings).
The modern version which takes an ops struct is called module_param_cb.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Phil Carmody <ext-phil.2.carmody@nokia.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Ville Syrjala <syrjala@sci.fi>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Alessandro Rubini <rubini@ipvvis.unipv.it>
Cc: Michal Januszewski <spock@gentoo.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Neil Brown <neilb@suse.de>
Cc: linux-kernel@vger.kernel.org
Cc: linux-input@vger.kernel.org
Cc: linux-fbdev-devel@lists.sourceforge.net
Cc: linux-nfs@vger.kernel.org
Cc: netdev@vger.kernel.org
2010-08-11 23:04:13 +09:30

281 lines
10 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))
#ifdef MODULE
#define ___module_cat(a,b) __mod_ ## a ## b
#define __module_cat(a,b) ___module_cat(a,b)
#define __MODULE_INFO(tag, name, info) \
static const char __module_cat(name,__LINE__)[] \
__used \
__attribute__((section(".modinfo"),unused)) = __stringify(tag) "=" info
#else /* !MODULE */
#define __MODULE_INFO(tag, name, info)
#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);
};
/* 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 *num;
const struct kernel_param_ops *ops;
unsigned int elemsize;
void *elem;
};
/* 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. perm sets the visibility in sysfs: 000 means it's
not there, read bits mean it's readable, write bits mean it's
writable. */
#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;
}
#define module_param_cb(name, ops, arg, perm) \
__module_param_call(MODULE_PARAM_PREFIX, \
name, ops, arg, __same_type(*(arg), bool), perm)
/*
* Helper functions: type is byte, short, ushort, int, uint, long,
* ulong, charp, bool or invbool, or XXX if you define param_ops_XXX
* and param_check_XXX.
*/
#define module_param_named(name, value, type, perm) \
param_check_##type(name, &(value)); \
module_param_cb(name, &param_ops_##type, &value, perm); \
__MODULE_PARM_TYPE(name, #type)
#define module_param(name, type, perm) \
module_param_named(name, name, type, perm)
#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 (for param_set_##type and param_get_##type)
* @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, &param_ops_##type, \
&var, __same_type(var, bool), perm)
#endif /* !MODULE */
/* Actually copy string: maxlen param is usually 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, \
&param_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,
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)
/* Comma-separated array: *nump is set to number they actually specified. */
#define module_param_array_named(name, array, type, nump, perm) \
static const struct kparam_array __param_arr_##name \
= { ARRAY_SIZE(array), nump, &param_ops_##type, \
sizeof(array[0]), array }; \
__module_param_call(MODULE_PARAM_PREFIX, name, \
&param_array_ops, \
.arr = &__param_arr_##name, \
__same_type(array[0], bool), perm); \
__MODULE_PARM_TYPE(name, "array of " #type)
#define module_param_array(name, type, nump, perm) \
module_param_array_named(name, name, type, nump, perm)
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 */