mirror of
https://github.com/torvalds/linux.git
synced 2024-11-25 13:41:51 +00:00
883ce42ec4
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
420 lines
15 KiB
C
420 lines
15 KiB
C
/*
|
|
* file.c - part of debugfs, a tiny little debug file system
|
|
*
|
|
* Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
|
|
* Copyright (C) 2004 IBM Inc.
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License version
|
|
* 2 as published by the Free Software Foundation.
|
|
*
|
|
* debugfs is for people to use instead of /proc or /sys.
|
|
* See Documentation/DocBook/filesystems for more details.
|
|
*
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/pagemap.h>
|
|
#include <linux/namei.h>
|
|
#include <linux/debugfs.h>
|
|
|
|
static ssize_t default_read_file(struct file *file, char __user *buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static ssize_t default_write_file(struct file *file, const char __user *buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
return count;
|
|
}
|
|
|
|
static int default_open(struct inode *inode, struct file *file)
|
|
{
|
|
if (inode->i_private)
|
|
file->private_data = inode->i_private;
|
|
|
|
return 0;
|
|
}
|
|
|
|
const struct file_operations debugfs_file_operations = {
|
|
.read = default_read_file,
|
|
.write = default_write_file,
|
|
.open = default_open,
|
|
};
|
|
|
|
static void *debugfs_follow_link(struct dentry *dentry, struct nameidata *nd)
|
|
{
|
|
nd_set_link(nd, dentry->d_inode->i_private);
|
|
return NULL;
|
|
}
|
|
|
|
const struct inode_operations debugfs_link_operations = {
|
|
.readlink = generic_readlink,
|
|
.follow_link = debugfs_follow_link,
|
|
};
|
|
|
|
static int debugfs_u8_set(void *data, u64 val)
|
|
{
|
|
*(u8 *)data = val;
|
|
return 0;
|
|
}
|
|
static int debugfs_u8_get(void *data, u64 *val)
|
|
{
|
|
*val = *(u8 *)data;
|
|
return 0;
|
|
}
|
|
DEFINE_SIMPLE_ATTRIBUTE(fops_u8, debugfs_u8_get, debugfs_u8_set, "%llu\n");
|
|
|
|
/**
|
|
* debugfs_create_u8 - create a debugfs file that is used to read and write an unsigned 8-bit value
|
|
* @name: a pointer to a string containing the name of the file to create.
|
|
* @mode: the permission that the file should have
|
|
* @parent: a pointer to the parent dentry for this file. This should be a
|
|
* directory dentry if set. If this parameter is %NULL, then the
|
|
* file will be created in the root of the debugfs filesystem.
|
|
* @value: a pointer to the variable that the file should read to and write
|
|
* from.
|
|
*
|
|
* This function creates a file in debugfs with the given name that
|
|
* contains the value of the variable @value. If the @mode variable is so
|
|
* set, it can be read from, and written to.
|
|
*
|
|
* This function will return a pointer to a dentry if it succeeds. This
|
|
* pointer must be passed to the debugfs_remove() function when the file is
|
|
* to be removed (no automatic cleanup happens if your module is unloaded,
|
|
* you are responsible here.) If an error occurs, %NULL will be returned.
|
|
*
|
|
* If debugfs is not enabled in the kernel, the value -%ENODEV will be
|
|
* returned. It is not wise to check for this value, but rather, check for
|
|
* %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
|
|
* code.
|
|
*/
|
|
struct dentry *debugfs_create_u8(const char *name, mode_t mode,
|
|
struct dentry *parent, u8 *value)
|
|
{
|
|
return debugfs_create_file(name, mode, parent, value, &fops_u8);
|
|
}
|
|
EXPORT_SYMBOL_GPL(debugfs_create_u8);
|
|
|
|
static int debugfs_u16_set(void *data, u64 val)
|
|
{
|
|
*(u16 *)data = val;
|
|
return 0;
|
|
}
|
|
static int debugfs_u16_get(void *data, u64 *val)
|
|
{
|
|
*val = *(u16 *)data;
|
|
return 0;
|
|
}
|
|
DEFINE_SIMPLE_ATTRIBUTE(fops_u16, debugfs_u16_get, debugfs_u16_set, "%llu\n");
|
|
|
|
/**
|
|
* debugfs_create_u16 - create a debugfs file that is used to read and write an unsigned 16-bit value
|
|
* @name: a pointer to a string containing the name of the file to create.
|
|
* @mode: the permission that the file should have
|
|
* @parent: a pointer to the parent dentry for this file. This should be a
|
|
* directory dentry if set. If this parameter is %NULL, then the
|
|
* file will be created in the root of the debugfs filesystem.
|
|
* @value: a pointer to the variable that the file should read to and write
|
|
* from.
|
|
*
|
|
* This function creates a file in debugfs with the given name that
|
|
* contains the value of the variable @value. If the @mode variable is so
|
|
* set, it can be read from, and written to.
|
|
*
|
|
* This function will return a pointer to a dentry if it succeeds. This
|
|
* pointer must be passed to the debugfs_remove() function when the file is
|
|
* to be removed (no automatic cleanup happens if your module is unloaded,
|
|
* you are responsible here.) If an error occurs, %NULL will be returned.
|
|
*
|
|
* If debugfs is not enabled in the kernel, the value -%ENODEV will be
|
|
* returned. It is not wise to check for this value, but rather, check for
|
|
* %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
|
|
* code.
|
|
*/
|
|
struct dentry *debugfs_create_u16(const char *name, mode_t mode,
|
|
struct dentry *parent, u16 *value)
|
|
{
|
|
return debugfs_create_file(name, mode, parent, value, &fops_u16);
|
|
}
|
|
EXPORT_SYMBOL_GPL(debugfs_create_u16);
|
|
|
|
static int debugfs_u32_set(void *data, u64 val)
|
|
{
|
|
*(u32 *)data = val;
|
|
return 0;
|
|
}
|
|
static int debugfs_u32_get(void *data, u64 *val)
|
|
{
|
|
*val = *(u32 *)data;
|
|
return 0;
|
|
}
|
|
DEFINE_SIMPLE_ATTRIBUTE(fops_u32, debugfs_u32_get, debugfs_u32_set, "%llu\n");
|
|
|
|
/**
|
|
* debugfs_create_u32 - create a debugfs file that is used to read and write an unsigned 32-bit value
|
|
* @name: a pointer to a string containing the name of the file to create.
|
|
* @mode: the permission that the file should have
|
|
* @parent: a pointer to the parent dentry for this file. This should be a
|
|
* directory dentry if set. If this parameter is %NULL, then the
|
|
* file will be created in the root of the debugfs filesystem.
|
|
* @value: a pointer to the variable that the file should read to and write
|
|
* from.
|
|
*
|
|
* This function creates a file in debugfs with the given name that
|
|
* contains the value of the variable @value. If the @mode variable is so
|
|
* set, it can be read from, and written to.
|
|
*
|
|
* This function will return a pointer to a dentry if it succeeds. This
|
|
* pointer must be passed to the debugfs_remove() function when the file is
|
|
* to be removed (no automatic cleanup happens if your module is unloaded,
|
|
* you are responsible here.) If an error occurs, %NULL will be returned.
|
|
*
|
|
* If debugfs is not enabled in the kernel, the value -%ENODEV will be
|
|
* returned. It is not wise to check for this value, but rather, check for
|
|
* %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
|
|
* code.
|
|
*/
|
|
struct dentry *debugfs_create_u32(const char *name, mode_t mode,
|
|
struct dentry *parent, u32 *value)
|
|
{
|
|
return debugfs_create_file(name, mode, parent, value, &fops_u32);
|
|
}
|
|
EXPORT_SYMBOL_GPL(debugfs_create_u32);
|
|
|
|
static int debugfs_u64_set(void *data, u64 val)
|
|
{
|
|
*(u64 *)data = val;
|
|
return 0;
|
|
}
|
|
|
|
static int debugfs_u64_get(void *data, u64 *val)
|
|
{
|
|
*val = *(u64 *)data;
|
|
return 0;
|
|
}
|
|
DEFINE_SIMPLE_ATTRIBUTE(fops_u64, debugfs_u64_get, debugfs_u64_set, "%llu\n");
|
|
|
|
/**
|
|
* debugfs_create_u64 - create a debugfs file that is used to read and write an unsigned 64-bit value
|
|
* @name: a pointer to a string containing the name of the file to create.
|
|
* @mode: the permission that the file should have
|
|
* @parent: a pointer to the parent dentry for this file. This should be a
|
|
* directory dentry if set. If this parameter is %NULL, then the
|
|
* file will be created in the root of the debugfs filesystem.
|
|
* @value: a pointer to the variable that the file should read to and write
|
|
* from.
|
|
*
|
|
* This function creates a file in debugfs with the given name that
|
|
* contains the value of the variable @value. If the @mode variable is so
|
|
* set, it can be read from, and written to.
|
|
*
|
|
* This function will return a pointer to a dentry if it succeeds. This
|
|
* pointer must be passed to the debugfs_remove() function when the file is
|
|
* to be removed (no automatic cleanup happens if your module is unloaded,
|
|
* you are responsible here.) If an error occurs, %NULL will be returned.
|
|
*
|
|
* If debugfs is not enabled in the kernel, the value -%ENODEV will be
|
|
* returned. It is not wise to check for this value, but rather, check for
|
|
* %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
|
|
* code.
|
|
*/
|
|
struct dentry *debugfs_create_u64(const char *name, mode_t mode,
|
|
struct dentry *parent, u64 *value)
|
|
{
|
|
return debugfs_create_file(name, mode, parent, value, &fops_u64);
|
|
}
|
|
EXPORT_SYMBOL_GPL(debugfs_create_u64);
|
|
|
|
DEFINE_SIMPLE_ATTRIBUTE(fops_x8, debugfs_u8_get, debugfs_u8_set, "0x%02llx\n");
|
|
|
|
DEFINE_SIMPLE_ATTRIBUTE(fops_x16, debugfs_u16_get, debugfs_u16_set, "0x%04llx\n");
|
|
|
|
DEFINE_SIMPLE_ATTRIBUTE(fops_x32, debugfs_u32_get, debugfs_u32_set, "0x%08llx\n");
|
|
|
|
/*
|
|
* debugfs_create_x{8,16,32} - create a debugfs file that is used to read and write an unsigned {8,16,32}-bit value
|
|
*
|
|
* These functions are exactly the same as the above functions (but use a hex
|
|
* output for the decimal challenged). For details look at the above unsigned
|
|
* decimal functions.
|
|
*/
|
|
|
|
/**
|
|
* debugfs_create_x8 - create a debugfs file that is used to read and write an unsigned 8-bit value
|
|
* @name: a pointer to a string containing the name of the file to create.
|
|
* @mode: the permission that the file should have
|
|
* @parent: a pointer to the parent dentry for this file. This should be a
|
|
* directory dentry if set. If this parameter is %NULL, then the
|
|
* file will be created in the root of the debugfs filesystem.
|
|
* @value: a pointer to the variable that the file should read to and write
|
|
* from.
|
|
*/
|
|
struct dentry *debugfs_create_x8(const char *name, mode_t mode,
|
|
struct dentry *parent, u8 *value)
|
|
{
|
|
return debugfs_create_file(name, mode, parent, value, &fops_x8);
|
|
}
|
|
EXPORT_SYMBOL_GPL(debugfs_create_x8);
|
|
|
|
/**
|
|
* debugfs_create_x16 - create a debugfs file that is used to read and write an unsigned 16-bit value
|
|
* @name: a pointer to a string containing the name of the file to create.
|
|
* @mode: the permission that the file should have
|
|
* @parent: a pointer to the parent dentry for this file. This should be a
|
|
* directory dentry if set. If this parameter is %NULL, then the
|
|
* file will be created in the root of the debugfs filesystem.
|
|
* @value: a pointer to the variable that the file should read to and write
|
|
* from.
|
|
*/
|
|
struct dentry *debugfs_create_x16(const char *name, mode_t mode,
|
|
struct dentry *parent, u16 *value)
|
|
{
|
|
return debugfs_create_file(name, mode, parent, value, &fops_x16);
|
|
}
|
|
EXPORT_SYMBOL_GPL(debugfs_create_x16);
|
|
|
|
/**
|
|
* debugfs_create_x32 - create a debugfs file that is used to read and write an unsigned 32-bit value
|
|
* @name: a pointer to a string containing the name of the file to create.
|
|
* @mode: the permission that the file should have
|
|
* @parent: a pointer to the parent dentry for this file. This should be a
|
|
* directory dentry if set. If this parameter is %NULL, then the
|
|
* file will be created in the root of the debugfs filesystem.
|
|
* @value: a pointer to the variable that the file should read to and write
|
|
* from.
|
|
*/
|
|
struct dentry *debugfs_create_x32(const char *name, mode_t mode,
|
|
struct dentry *parent, u32 *value)
|
|
{
|
|
return debugfs_create_file(name, mode, parent, value, &fops_x32);
|
|
}
|
|
EXPORT_SYMBOL_GPL(debugfs_create_x32);
|
|
|
|
static ssize_t read_file_bool(struct file *file, char __user *user_buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
char buf[3];
|
|
u32 *val = file->private_data;
|
|
|
|
if (*val)
|
|
buf[0] = 'Y';
|
|
else
|
|
buf[0] = 'N';
|
|
buf[1] = '\n';
|
|
buf[2] = 0x00;
|
|
return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
|
|
}
|
|
|
|
static ssize_t write_file_bool(struct file *file, const char __user *user_buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
char buf[32];
|
|
int buf_size;
|
|
u32 *val = file->private_data;
|
|
|
|
buf_size = min(count, (sizeof(buf)-1));
|
|
if (copy_from_user(buf, user_buf, buf_size))
|
|
return -EFAULT;
|
|
|
|
switch (buf[0]) {
|
|
case 'y':
|
|
case 'Y':
|
|
case '1':
|
|
*val = 1;
|
|
break;
|
|
case 'n':
|
|
case 'N':
|
|
case '0':
|
|
*val = 0;
|
|
break;
|
|
}
|
|
|
|
return count;
|
|
}
|
|
|
|
static const struct file_operations fops_bool = {
|
|
.read = read_file_bool,
|
|
.write = write_file_bool,
|
|
.open = default_open,
|
|
};
|
|
|
|
/**
|
|
* debugfs_create_bool - create a debugfs file that is used to read and write a boolean value
|
|
* @name: a pointer to a string containing the name of the file to create.
|
|
* @mode: the permission that the file should have
|
|
* @parent: a pointer to the parent dentry for this file. This should be a
|
|
* directory dentry if set. If this parameter is %NULL, then the
|
|
* file will be created in the root of the debugfs filesystem.
|
|
* @value: a pointer to the variable that the file should read to and write
|
|
* from.
|
|
*
|
|
* This function creates a file in debugfs with the given name that
|
|
* contains the value of the variable @value. If the @mode variable is so
|
|
* set, it can be read from, and written to.
|
|
*
|
|
* This function will return a pointer to a dentry if it succeeds. This
|
|
* pointer must be passed to the debugfs_remove() function when the file is
|
|
* to be removed (no automatic cleanup happens if your module is unloaded,
|
|
* you are responsible here.) If an error occurs, %NULL will be returned.
|
|
*
|
|
* If debugfs is not enabled in the kernel, the value -%ENODEV will be
|
|
* returned. It is not wise to check for this value, but rather, check for
|
|
* %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
|
|
* code.
|
|
*/
|
|
struct dentry *debugfs_create_bool(const char *name, mode_t mode,
|
|
struct dentry *parent, u32 *value)
|
|
{
|
|
return debugfs_create_file(name, mode, parent, value, &fops_bool);
|
|
}
|
|
EXPORT_SYMBOL_GPL(debugfs_create_bool);
|
|
|
|
static ssize_t read_file_blob(struct file *file, char __user *user_buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
struct debugfs_blob_wrapper *blob = file->private_data;
|
|
return simple_read_from_buffer(user_buf, count, ppos, blob->data,
|
|
blob->size);
|
|
}
|
|
|
|
static const struct file_operations fops_blob = {
|
|
.read = read_file_blob,
|
|
.open = default_open,
|
|
};
|
|
|
|
/**
|
|
* debugfs_create_blob - create a debugfs file that is used to read and write a binary blob
|
|
* @name: a pointer to a string containing the name of the file to create.
|
|
* @mode: the permission that the file should have
|
|
* @parent: a pointer to the parent dentry for this file. This should be a
|
|
* directory dentry if set. If this parameter is %NULL, then the
|
|
* file will be created in the root of the debugfs filesystem.
|
|
* @blob: a pointer to a struct debugfs_blob_wrapper which contains a pointer
|
|
* to the blob data and the size of the data.
|
|
*
|
|
* This function creates a file in debugfs with the given name that exports
|
|
* @blob->data as a binary blob. If the @mode variable is so set it can be
|
|
* read from. Writing is not supported.
|
|
*
|
|
* This function will return a pointer to a dentry if it succeeds. This
|
|
* pointer must be passed to the debugfs_remove() function when the file is
|
|
* to be removed (no automatic cleanup happens if your module is unloaded,
|
|
* you are responsible here.) If an error occurs, %NULL will be returned.
|
|
*
|
|
* If debugfs is not enabled in the kernel, the value -%ENODEV will be
|
|
* returned. It is not wise to check for this value, but rather, check for
|
|
* %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
|
|
* code.
|
|
*/
|
|
struct dentry *debugfs_create_blob(const char *name, mode_t mode,
|
|
struct dentry *parent,
|
|
struct debugfs_blob_wrapper *blob)
|
|
{
|
|
return debugfs_create_file(name, mode, parent, blob, &fops_blob);
|
|
}
|
|
EXPORT_SYMBOL_GPL(debugfs_create_blob);
|