539 lines
19 KiB
C
539 lines
19 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef _LINUX_MODULE_PARAMS_H
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#define _LINUX_MODULE_PARAMS_H
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/* (C) Copyright 2001, 2002 Rusty Russell IBM Corporation */
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#include <linux/init.h>
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#include <linux/stringify.h>
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#include <linux/kernel.h>
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/* You can override this manually, but generally this should match the
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module name. */
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#ifdef MODULE
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#define MODULE_PARAM_PREFIX /* empty */
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#else
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#define MODULE_PARAM_PREFIX KBUILD_MODNAME "."
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#endif
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/* Chosen so that structs with an unsigned long line up. */
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#define MAX_PARAM_PREFIX_LEN (64 - sizeof(unsigned long))
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#ifdef MODULE
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#define __MODULE_INFO(tag, name, info) \
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static const char __UNIQUE_ID(name)[] \
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__used __attribute__((section(".modinfo"), unused, aligned(1))) \
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= __stringify(tag) "=" info
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#else /* !MODULE */
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/* This struct is here for syntactic coherency, it is not used */
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#define __MODULE_INFO(tag, name, info) \
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struct __UNIQUE_ID(name) {}
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#endif
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#define __MODULE_PARM_TYPE(name, _type) \
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__MODULE_INFO(parmtype, name##type, #name ":" _type)
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/* One for each parameter, describing how to use it. Some files do
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multiple of these per line, so can't just use MODULE_INFO. */
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#define MODULE_PARM_DESC(_parm, desc) \
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__MODULE_INFO(parm, _parm, #_parm ":" desc)
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struct kernel_param;
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/*
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* Flags available for kernel_param_ops
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*
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* NOARG - the parameter allows for no argument (foo instead of foo=1)
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*/
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enum {
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KERNEL_PARAM_OPS_FL_NOARG = (1 << 0)
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};
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struct kernel_param_ops {
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/* How the ops should behave */
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unsigned int flags;
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/* Returns 0, or -errno. arg is in kp->arg. */
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int (*set)(const char *val, const struct kernel_param *kp);
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/* Returns length written or -errno. Buffer is 4k (ie. be short!) */
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int (*get)(char *buffer, const struct kernel_param *kp);
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/* Optional function to free kp->arg when module unloaded. */
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void (*free)(void *arg);
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};
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/*
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* Flags available for kernel_param
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*
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* UNSAFE - the parameter is dangerous and setting it will taint the kernel
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* HWPARAM - Hardware param not permitted in lockdown mode
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*/
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enum {
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KERNEL_PARAM_FL_UNSAFE = (1 << 0),
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KERNEL_PARAM_FL_HWPARAM = (1 << 1),
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};
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struct kernel_param {
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const char *name;
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struct module *mod;
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const struct kernel_param_ops *ops;
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const u16 perm;
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s8 level;
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u8 flags;
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union {
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void *arg;
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const struct kparam_string *str;
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const struct kparam_array *arr;
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};
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};
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extern const struct kernel_param __start___param[], __stop___param[];
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/* Special one for strings we want to copy into */
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struct kparam_string {
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unsigned int maxlen;
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char *string;
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};
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/* Special one for arrays */
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struct kparam_array
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{
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unsigned int max;
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unsigned int elemsize;
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unsigned int *num;
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const struct kernel_param_ops *ops;
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void *elem;
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};
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/**
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* module_param - typesafe helper for a module/cmdline parameter
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* @value: the variable to alter, and exposed parameter name.
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* @type: the type of the parameter
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* @perm: visibility in sysfs.
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*
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* @value becomes the module parameter, or (prefixed by KBUILD_MODNAME and a
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* ".") the kernel commandline parameter. Note that - is changed to _, so
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* the user can use "foo-bar=1" even for variable "foo_bar".
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*
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* @perm is 0 if the the variable is not to appear in sysfs, or 0444
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* for world-readable, 0644 for root-writable, etc. Note that if it
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* is writable, you may need to use kernel_param_lock() around
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* accesses (esp. charp, which can be kfreed when it changes).
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*
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* The @type is simply pasted to refer to a param_ops_##type and a
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* param_check_##type: for convenience many standard types are provided but
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* you can create your own by defining those variables.
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*
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* Standard types are:
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* byte, short, ushort, int, uint, long, ulong
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* charp: a character pointer
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* bool: a bool, values 0/1, y/n, Y/N.
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* invbool: the above, only sense-reversed (N = true).
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*/
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#define module_param(name, type, perm) \
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module_param_named(name, name, type, perm)
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/**
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* module_param_unsafe - same as module_param but taints kernel
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*/
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#define module_param_unsafe(name, type, perm) \
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module_param_named_unsafe(name, name, type, perm)
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/**
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* module_param_named - typesafe helper for a renamed module/cmdline parameter
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* @name: a valid C identifier which is the parameter name.
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* @value: the actual lvalue to alter.
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* @type: the type of the parameter
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* @perm: visibility in sysfs.
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*
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* Usually it's a good idea to have variable names and user-exposed names the
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* same, but that's harder if the variable must be non-static or is inside a
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* structure. This allows exposure under a different name.
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*/
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#define module_param_named(name, value, type, perm) \
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param_check_##type(name, &(value)); \
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module_param_cb(name, ¶m_ops_##type, &value, perm); \
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__MODULE_PARM_TYPE(name, #type)
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/**
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* module_param_named_unsafe - same as module_param_named but taints kernel
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*/
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#define module_param_named_unsafe(name, value, type, perm) \
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param_check_##type(name, &(value)); \
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module_param_cb_unsafe(name, ¶m_ops_##type, &value, perm); \
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__MODULE_PARM_TYPE(name, #type)
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/**
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* module_param_cb - general callback for a module/cmdline parameter
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* @name: a valid C identifier which is the parameter name.
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* @ops: the set & get operations for this parameter.
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* @perm: visibility in sysfs.
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*
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* The ops can have NULL set or get functions.
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*/
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#define module_param_cb(name, ops, arg, perm) \
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__module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, -1, 0)
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#define module_param_cb_unsafe(name, ops, arg, perm) \
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__module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, -1, \
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KERNEL_PARAM_FL_UNSAFE)
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/**
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* <level>_param_cb - general callback for a module/cmdline parameter
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* to be evaluated before certain initcall level
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* @name: a valid C identifier which is the parameter name.
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* @ops: the set & get operations for this parameter.
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* @perm: visibility in sysfs.
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*
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* The ops can have NULL set or get functions.
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*/
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#define __level_param_cb(name, ops, arg, perm, level) \
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__module_param_call(MODULE_PARAM_PREFIX, name, ops, arg, perm, level, 0)
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#define core_param_cb(name, ops, arg, perm) \
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__level_param_cb(name, ops, arg, perm, 1)
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#define postcore_param_cb(name, ops, arg, perm) \
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__level_param_cb(name, ops, arg, perm, 2)
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#define arch_param_cb(name, ops, arg, perm) \
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__level_param_cb(name, ops, arg, perm, 3)
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#define subsys_param_cb(name, ops, arg, perm) \
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__level_param_cb(name, ops, arg, perm, 4)
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#define fs_param_cb(name, ops, arg, perm) \
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__level_param_cb(name, ops, arg, perm, 5)
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#define device_param_cb(name, ops, arg, perm) \
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__level_param_cb(name, ops, arg, perm, 6)
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#define late_param_cb(name, ops, arg, perm) \
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__level_param_cb(name, ops, arg, perm, 7)
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/* On alpha, ia64 and ppc64 relocations to global data cannot go into
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read-only sections (which is part of respective UNIX ABI on these
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platforms). So 'const' makes no sense and even causes compile failures
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with some compilers. */
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#if defined(CONFIG_ALPHA) || defined(CONFIG_IA64) || defined(CONFIG_PPC64)
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#define __moduleparam_const
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#else
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#define __moduleparam_const const
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#endif
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/* This is the fundamental function for registering boot/module
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parameters. */
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#define __module_param_call(prefix, name, ops, arg, perm, level, flags) \
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/* Default value instead of permissions? */ \
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static const char __param_str_##name[] = prefix #name; \
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static struct kernel_param __moduleparam_const __param_##name \
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__used \
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__attribute__ ((unused,__section__ ("__param"),aligned(sizeof(void *)))) \
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= { __param_str_##name, THIS_MODULE, ops, \
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VERIFY_OCTAL_PERMISSIONS(perm), level, flags, { arg } }
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/* Obsolete - use module_param_cb() */
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#define module_param_call(name, _set, _get, arg, perm) \
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static const struct kernel_param_ops __param_ops_##name = \
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{ .flags = 0, .set = _set, .get = _get }; \
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__module_param_call(MODULE_PARAM_PREFIX, \
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name, &__param_ops_##name, arg, perm, -1, 0)
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#ifdef CONFIG_SYSFS
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extern void kernel_param_lock(struct module *mod);
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extern void kernel_param_unlock(struct module *mod);
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#else
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static inline void kernel_param_lock(struct module *mod)
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{
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}
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static inline void kernel_param_unlock(struct module *mod)
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{
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}
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#endif
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#ifndef MODULE
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/**
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* core_param - define a historical core kernel parameter.
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* @name: the name of the cmdline and sysfs parameter (often the same as var)
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* @var: the variable
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* @type: the type of the parameter
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* @perm: visibility in sysfs
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*
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* core_param is just like module_param(), but cannot be modular and
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* doesn't add a prefix (such as "printk."). This is for compatibility
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* with __setup(), and it makes sense as truly core parameters aren't
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* tied to the particular file they're in.
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*/
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#define core_param(name, var, type, perm) \
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param_check_##type(name, &(var)); \
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__module_param_call("", name, ¶m_ops_##type, &var, perm, -1, 0)
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/**
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* core_param_unsafe - same as core_param but taints kernel
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*/
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#define core_param_unsafe(name, var, type, perm) \
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param_check_##type(name, &(var)); \
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__module_param_call("", name, ¶m_ops_##type, &var, perm, \
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-1, KERNEL_PARAM_FL_UNSAFE)
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#endif /* !MODULE */
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/**
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* module_param_string - a char array parameter
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* @name: the name of the parameter
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* @string: the string variable
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* @len: the maximum length of the string, incl. terminator
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* @perm: visibility in sysfs.
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*
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* This actually copies the string when it's set (unlike type charp).
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* @len is usually just sizeof(string).
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*/
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#define module_param_string(name, string, len, perm) \
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static const struct kparam_string __param_string_##name \
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= { len, string }; \
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__module_param_call(MODULE_PARAM_PREFIX, name, \
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¶m_ops_string, \
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.str = &__param_string_##name, perm, -1, 0);\
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__MODULE_PARM_TYPE(name, "string")
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/**
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* parameq - checks if two parameter names match
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* @name1: parameter name 1
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* @name2: parameter name 2
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*
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* Returns true if the two parameter names are equal.
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* Dashes (-) are considered equal to underscores (_).
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*/
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extern bool parameq(const char *name1, const char *name2);
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/**
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* parameqn - checks if two parameter names match
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* @name1: parameter name 1
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* @name2: parameter name 2
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* @n: the length to compare
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*
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* Similar to parameq(), except it compares @n characters.
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*/
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extern bool parameqn(const char *name1, const char *name2, size_t n);
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/* Called on module insert or kernel boot */
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extern char *parse_args(const char *name,
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char *args,
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const struct kernel_param *params,
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unsigned num,
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s16 level_min,
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s16 level_max,
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void *arg,
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int (*unknown)(char *param, char *val,
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const char *doing, void *arg));
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/* Called by module remove. */
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#ifdef CONFIG_SYSFS
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extern void destroy_params(const struct kernel_param *params, unsigned num);
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#else
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static inline void destroy_params(const struct kernel_param *params,
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unsigned num)
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{
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}
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#endif /* !CONFIG_SYSFS */
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/* All the helper functions */
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/* The macros to do compile-time type checking stolen from Jakub
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Jelinek, who IIRC came up with this idea for the 2.4 module init code. */
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#define __param_check(name, p, type) \
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static inline type __always_unused *__check_##name(void) { return(p); }
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extern const struct kernel_param_ops param_ops_byte;
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extern int param_set_byte(const char *val, const struct kernel_param *kp);
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extern int param_get_byte(char *buffer, const struct kernel_param *kp);
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#define param_check_byte(name, p) __param_check(name, p, unsigned char)
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extern const struct kernel_param_ops param_ops_short;
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extern int param_set_short(const char *val, const struct kernel_param *kp);
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extern int param_get_short(char *buffer, const struct kernel_param *kp);
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#define param_check_short(name, p) __param_check(name, p, short)
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extern const struct kernel_param_ops param_ops_ushort;
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extern int param_set_ushort(const char *val, const struct kernel_param *kp);
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extern int param_get_ushort(char *buffer, const struct kernel_param *kp);
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#define param_check_ushort(name, p) __param_check(name, p, unsigned short)
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extern const struct kernel_param_ops param_ops_int;
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extern int param_set_int(const char *val, const struct kernel_param *kp);
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extern int param_get_int(char *buffer, const struct kernel_param *kp);
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#define param_check_int(name, p) __param_check(name, p, int)
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extern const struct kernel_param_ops param_ops_uint;
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extern int param_set_uint(const char *val, const struct kernel_param *kp);
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extern int param_get_uint(char *buffer, const struct kernel_param *kp);
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#define param_check_uint(name, p) __param_check(name, p, unsigned int)
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extern const struct kernel_param_ops param_ops_long;
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extern int param_set_long(const char *val, const struct kernel_param *kp);
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extern int param_get_long(char *buffer, const struct kernel_param *kp);
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#define param_check_long(name, p) __param_check(name, p, long)
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extern const struct kernel_param_ops param_ops_ulong;
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extern int param_set_ulong(const char *val, const struct kernel_param *kp);
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extern int param_get_ulong(char *buffer, const struct kernel_param *kp);
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#define param_check_ulong(name, p) __param_check(name, p, unsigned long)
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extern const struct kernel_param_ops param_ops_ullong;
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extern int param_set_ullong(const char *val, const struct kernel_param *kp);
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extern int param_get_ullong(char *buffer, const struct kernel_param *kp);
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#define param_check_ullong(name, p) __param_check(name, p, unsigned long long)
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extern const struct kernel_param_ops param_ops_charp;
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extern int param_set_charp(const char *val, const struct kernel_param *kp);
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extern int param_get_charp(char *buffer, const struct kernel_param *kp);
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extern void param_free_charp(void *arg);
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#define param_check_charp(name, p) __param_check(name, p, char *)
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/* We used to allow int as well as bool. We're taking that away! */
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extern const struct kernel_param_ops param_ops_bool;
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extern int param_set_bool(const char *val, const struct kernel_param *kp);
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extern int param_get_bool(char *buffer, const struct kernel_param *kp);
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#define param_check_bool(name, p) __param_check(name, p, bool)
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extern const struct kernel_param_ops param_ops_bool_enable_only;
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extern int param_set_bool_enable_only(const char *val,
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const struct kernel_param *kp);
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/* getter is the same as for the regular bool */
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#define param_check_bool_enable_only param_check_bool
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extern const struct kernel_param_ops param_ops_invbool;
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extern int param_set_invbool(const char *val, const struct kernel_param *kp);
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extern int param_get_invbool(char *buffer, const struct kernel_param *kp);
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#define param_check_invbool(name, p) __param_check(name, p, bool)
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/* An int, which can only be set like a bool (though it shows as an int). */
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extern const struct kernel_param_ops param_ops_bint;
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extern int param_set_bint(const char *val, const struct kernel_param *kp);
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#define param_get_bint param_get_int
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#define param_check_bint param_check_int
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/**
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* module_param_array - a parameter which is an array of some type
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* @name: the name of the array variable
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* @type: the type, as per module_param()
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* @nump: optional pointer filled in with the number written
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* @perm: visibility in sysfs
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*
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* Input and output are as comma-separated values. Commas inside values
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* don't work properly (eg. an array of charp).
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*
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* ARRAY_SIZE(@name) is used to determine the number of elements in the
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* array, so the definition must be visible.
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*/
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#define module_param_array(name, type, nump, perm) \
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module_param_array_named(name, name, type, nump, perm)
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/**
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* module_param_array_named - renamed parameter which is an array of some type
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* @name: a valid C identifier which is the parameter name
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* @array: the name of the array variable
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* @type: the type, as per module_param()
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* @nump: optional pointer filled in with the number written
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* @perm: visibility in sysfs
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*
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* This exposes a different name than the actual variable name. See
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* module_param_named() for why this might be necessary.
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*/
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#define module_param_array_named(name, array, type, nump, perm) \
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param_check_##type(name, &(array)[0]); \
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static const struct kparam_array __param_arr_##name \
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= { .max = ARRAY_SIZE(array), .num = nump, \
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.ops = ¶m_ops_##type, \
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.elemsize = sizeof(array[0]), .elem = array }; \
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__module_param_call(MODULE_PARAM_PREFIX, name, \
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¶m_array_ops, \
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.arr = &__param_arr_##name, \
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perm, -1, 0); \
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__MODULE_PARM_TYPE(name, "array of " #type)
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enum hwparam_type {
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hwparam_ioport, /* Module parameter configures an I/O port */
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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 IRQ */
|
|
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, \
|
|
¶m_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 = ¶m_ops_##type, \
|
|
.elemsize = sizeof(name[0]), .elem = name }; \
|
|
__module_param_call(MODULE_PARAM_PREFIX, name, \
|
|
¶m_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 */
|