linux/include/linux/moduleparam.h
Ivan Kokshaysky 91d35dd93e moduleparam: fix alpha, ia64 and ppc64 compile failures
On alpha, ia64 and ppc64 only relocations to local data can go into
read-only sections. The vast majority of module parameters use the global
generic param_set_*/param_get_* functions, so the 'const' attribute for
struct kernel_param is not only useless, but it also causes compile
failures due to 'section type conflict' in those rare cases where
param_set/get are local functions.

This fixes http://bugzilla.kernel.org/show_bug.cgi?id=8964

Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Richard Henderson <rth@twiddle.net>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Adrian Bunk <bunk@stusta.de>
Cc: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-13 16:21:19 -08:00

205 lines
7.5 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
#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;
/* Returns 0, or -errno. arg is in kp->arg. */
typedef int (*param_set_fn)(const char *val, struct kernel_param *kp);
/* Returns length written or -errno. Buffer is 4k (ie. be short!) */
typedef int (*param_get_fn)(char *buffer, struct kernel_param *kp);
struct kernel_param {
const char *name;
unsigned int perm;
param_set_fn set;
param_get_fn get;
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;
param_set_fn set;
param_get_fn get;
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, set, get, arg, perm) \
/* Default value instead of permissions? */ \
static int __param_perm_check_##name __attribute__((unused)) = \
BUILD_BUG_ON_ZERO((perm) < 0 || (perm) > 0777 || ((perm) & 2)); \
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, perm, set, get, { arg } }
#define module_param_call(name, set, get, arg, perm) \
__module_param_call(MODULE_PARAM_PREFIX, name, set, get, arg, perm)
/* Helper functions: type is byte, short, ushort, int, uint, long,
ulong, charp, bool or invbool, or XXX if you define param_get_XXX,
param_set_XXX and param_check_XXX. */
#define module_param_named(name, value, type, perm) \
param_check_##type(name, &(value)); \
module_param_call(name, param_set_##type, param_get_##type, &value, perm); \
__MODULE_PARM_TYPE(name, #type)
#define module_param(name, type, perm) \
module_param_named(name, name, type, perm)
/* 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(name, param_set_copystring, param_get_string, \
.str = &__param_string_##name, 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));
/* 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 int param_set_byte(const char *val, struct kernel_param *kp);
extern int param_get_byte(char *buffer, struct kernel_param *kp);
#define param_check_byte(name, p) __param_check(name, p, unsigned char)
extern int param_set_short(const char *val, struct kernel_param *kp);
extern int param_get_short(char *buffer, struct kernel_param *kp);
#define param_check_short(name, p) __param_check(name, p, short)
extern int param_set_ushort(const char *val, struct kernel_param *kp);
extern int param_get_ushort(char *buffer, struct kernel_param *kp);
#define param_check_ushort(name, p) __param_check(name, p, unsigned short)
extern int param_set_int(const char *val, struct kernel_param *kp);
extern int param_get_int(char *buffer, struct kernel_param *kp);
#define param_check_int(name, p) __param_check(name, p, int)
extern int param_set_uint(const char *val, struct kernel_param *kp);
extern int param_get_uint(char *buffer, struct kernel_param *kp);
#define param_check_uint(name, p) __param_check(name, p, unsigned int)
extern int param_set_long(const char *val, struct kernel_param *kp);
extern int param_get_long(char *buffer, struct kernel_param *kp);
#define param_check_long(name, p) __param_check(name, p, long)
extern int param_set_ulong(const char *val, struct kernel_param *kp);
extern int param_get_ulong(char *buffer, struct kernel_param *kp);
#define param_check_ulong(name, p) __param_check(name, p, unsigned long)
extern int param_set_charp(const char *val, struct kernel_param *kp);
extern int param_get_charp(char *buffer, struct kernel_param *kp);
#define param_check_charp(name, p) __param_check(name, p, char *)
extern int param_set_bool(const char *val, struct kernel_param *kp);
extern int param_get_bool(char *buffer, struct kernel_param *kp);
#define param_check_bool(name, p) __param_check(name, p, int)
extern int param_set_invbool(const char *val, struct kernel_param *kp);
extern int param_get_invbool(char *buffer, struct kernel_param *kp);
#define param_check_invbool(name, p) __param_check(name, p, int)
/* 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_set_##type, param_get_##type,\
sizeof(array[0]), array }; \
module_param_call(name, param_array_set, param_array_get, \
.arr = &__param_arr_##name, 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 int param_array_set(const char *val, struct kernel_param *kp);
extern int param_array_get(char *buffer, struct kernel_param *kp);
extern int param_set_copystring(const char *val, struct kernel_param *kp);
extern int param_get_string(char *buffer, 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,
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,
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 */