davidlt/kernel-ark
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity
0538421343
kernel-ark/include/linux/moduleparam.h
David Howells bf616d21f4 Annotate module params that specify hardware parameters (eg. ioport) 
Provided an annotation for module parameters that specify hardware
parameters (such as io ports, iomem addresses, irqs, dma channels, fixed
dma buffers and other types).

This will enable such parameters to be locked down in the core parameter
parser for secure boot support.

I've also included annotations as to what sort of hardware configuration
each module is dealing with for future use.  Some of these are
straightforward (ioport, iomem, irq, dma), but there are also:

 (1) drivers that switch the semantics of a parameter between ioport and
     iomem depending on a second parameter,

 (2) drivers that appear to reserve a CPU memory buffer at a fixed address,

 (3) other parameters, such as bus types and irq selection bitmasks.

For the moment, the hardware configuration type isn't actually stored,
though its validity is checked.

Signed-off-by: David Howells <dhowells@redhat.com>
2017-04-04 16:54:21 +01:00

546 lines
20 KiB
C
Raw Blame History

#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;
/*
* Flags available for kernel_param_ops
*
* NOARG - the parameter allows for no argument (foo instead of foo=1)
*/
enum {
KERNEL_PARAM_OPS_FL_NOARG = (1 << 0)
};
struct kernel_param_ops {
/* How the ops should behave */
unsigned int flags;
/* 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);
};
/*
* Flags available for kernel_param
*
* UNSAFE - the parameter is dangerous and setting it will taint the kernel
* HWPARAM - Hardware param not permitted in lockdown mode
*/
enum {
KERNEL_PARAM_FL_UNSAFE = (1 << 0),
KERNEL_PARAM_FL_HWPARAM = (1 << 1),
};
struct kernel_param {
const char *name;
struct module *mod;
const struct kernel_param_ops *ops;
const u16 perm;
s8 level;
u8 flags;
union {
void *arg;
const struct kparam_string *str;
const struct kparam_array *arr;
};
};
extern const struct kernel_param __start___param[], __stop___param[];
/* 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 kernel_param_lock() 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_unsafe - same as module_param but taints kernel
*/
#define module_param_unsafe(name, type, perm) \
module_param_named_unsafe(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, &param_ops_##type, &value, perm); \
__MODULE_PARM_TYPE(name, #type)
/**
* module_param_named_unsafe - same as module_param_named but taints kernel
*/
#define module_param_named_unsafe(name, value, type, perm) \
param_check_##type(name, &(value)); \
module_param_cb_unsafe(name, &param_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, 0)
#define module_param_cb_unsafe(name, ops, arg, perm) \
__module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, -1, \
KERNEL_PARAM_FL_UNSAFE)
/**
* <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, 0)
#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, flags) \
/* Default value instead of permissions? */ \
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, 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 }; \
__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;
}
#ifdef CONFIG_SYSFS
extern void kernel_param_lock(struct module *mod);
extern void kernel_param_unlock(struct module *mod);
#else
static inline void kernel_param_lock(struct module *mod)
{
}
static inline void kernel_param_unlock(struct module *mod)
{
}
#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, &param_ops_##type, &var, perm, -1, 0)
/**
* core_param_unsafe - same as core_param but taints kernel
*/
#define core_param_unsafe(name, var, type, perm) \
param_check_##type(name, &(var)); \
__module_param_call("", name, &param_ops_##type, &var, perm, \
-1, KERNEL_PARAM_FL_UNSAFE)
#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, \
&param_ops_string, \
.str = &__param_string_##name, perm, -1, 0);\
__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 char *parse_args(const char *name,
char *args,
const struct kernel_param *params,
unsigned num,
s16 level_min,
s16 level_max,
void *arg,
int (*unknown)(char *param, char *val,
const char *doing, void *arg));
/* 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 __always_unused *__check_##name(void) { return(p); }
extern const 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 const 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 const 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 const 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 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);
#define param_check_uint(name, p) __param_check(name, p, unsigned int)
extern const 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 const 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 const 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 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);
extern void param_free_charp(void *arg);
#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 const 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 const struct kernel_param_ops param_ops_bool_enable_only;
extern int param_set_bool_enable_only(const char *val,
const struct kernel_param *kp);
/* getter is the same as for the regular bool */
#define param_check_bool_enable_only param_check_bool
extern const 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 const 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 = &param_ops_##type, \
.elemsize = sizeof(array[0]), .elem = array }; \
__module_param_call(MODULE_PARAM_PREFIX, name, \
&param_array_ops, \
.arr = &__param_arr_##name, \
perm, -1, 0); \
__MODULE_PARM_TYPE(name, "array of " #type)
enum hwparam_type {
hwparam_ioport, /* Module parameter configures an I/O port */
hwparam_iomem, /* Module parameter configures an I/O mem address */
hwparam_ioport_or_iomem, /* Module parameter could be either, depending on other option */
hwparam_irq, /* Module parameter configures an I/O port */
hwparam_dma, /* Module parameter configures a DMA channel */
hwparam_dma_addr, /* Module parameter configures a DMA buffer address */
hwparam_other, /* Module parameter configures some other value */
};
/**
* module_param_hw_named - A parameter representing a hw parameters
* @name: a valid C identifier which is the parameter name.
* @value: the actual lvalue to alter.
* @type: the type of the parameter
* @hwtype: what the value represents (enum hwparam_type)
* @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_hw_named(name, value, type, hwtype, perm) \
param_check_##type(name, &(value)); \
__module_param_call(MODULE_PARAM_PREFIX, name, \
&param_ops_##type, &value, \
perm, -1, \
KERNEL_PARAM_FL_HWPARAM | (hwparam_##hwtype & 0)); \
__MODULE_PARM_TYPE(name, #type)
#define module_param_hw(name, type, hwtype, perm) \
module_param_hw_named(name, name, type, hwtype, perm)
/**
* module_param_hw_array - A parameter representing an array of hw parameters
* @name: the name of the array variable
* @type: the type, as per module_param()
* @hwtype: what the value represents (enum hwparam_type)
* @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_hw_array(name, type, hwtype, nump, perm) \
param_check_##type(name, &(name)[0]); \
static const struct kparam_array __param_arr_##name \
= { .max = ARRAY_SIZE(name), .num = nump, \
.ops = &param_ops_##type, \
.elemsize = sizeof(name[0]), .elem = name }; \
__module_param_call(MODULE_PARAM_PREFIX, name, \
&param_array_ops, \
.arr = &__param_arr_##name, \
perm, -1, \
KERNEL_PARAM_FL_HWPARAM | (hwparam_##hwtype & 0)); \
__MODULE_PARM_TYPE(name, "array of " #type)
extern const struct kernel_param_ops param_array_ops;
extern const 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/module/.../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 */
Reference in New Issue View Git Blame Copy Permalink