debugfs.h
// SPDX-License-Identifier: GPL-2.0
/*
* debugfs.h - a tiny little debug file system
*
* Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
* Copyright (C) 2004 IBM Inc.
*
* debugfs is for people to use instead of /proc or /sys.
* See Documentation/filesystems/ for more details.
*/
#ifndef _DEBUGFS_H_
#define _DEBUGFS_H_
#include <linux/fs.h>
#include <linux/seq_file.h>
#include <linux/types.h>
#include <linux/compiler.h>
struct device;
struct file_operations;
struct debugfs_blob_wrapper {
void *data;
unsigned long size;
};
struct debugfs_reg32 {
char *name;
unsigned long offset;
};
struct debugfs_regset32 {
const struct debugfs_reg32 *regs;
int nregs;
void __iomem *base;
struct device *dev; /* Optional device for Runtime PM */
};
struct debugfs_u32_array {
u32 *array;
u32 n_elements;
};
extern struct dentry *arch_debugfs_dir;
#define DEFINE_DEBUGFS_ATTRIBUTE(__fops, __get, __set, __fmt) \
static int __fops ## _open(struct inode *inode, struct file *file) \
{ \
__simple_attr_check_format(__fmt, 0ull); \
return simple_attr_open(inode, file, __get, __set, __fmt); \
} \
static const struct file_operations __fops = { \
.owner = THIS_MODULE, \
.open = __fops ## _open, \
.release = simple_attr_release, \
.read = debugfs_attr_read, \
.write = debugfs_attr_write, \
.llseek = no_llseek, \
}
typedef struct vfsmount *(*debugfs_automount_t)(struct dentry *, void *);
#if defined(CONFIG_DEBUG_FS)
struct dentry *debugfs_lookup(const char *name, struct dentry *parent);
struct dentry *debugfs_create_file(const char *name, umode_t mode,
struct dentry *parent, void *data,
const struct file_operations *fops);
struct dentry *debugfs_create_file_unsafe(const char *name, umode_t mode,
struct dentry *parent, void *data,
const struct file_operations *fops);
void debugfs_create_file_size(const char *name, umode_t mode,
struct dentry *parent, void *data,
const struct file_operations *fops,
loff_t file_size);
struct dentry *debugfs_create_dir(const char *name, struct dentry *parent);
struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent,
const char *dest);
struct dentry *debugfs_create_automount(const char *name,
struct dentry *parent,
debugfs_automount_t f,
void *data);
void debugfs_remove(struct dentry *dentry);
#define debugfs_remove_recursive debugfs_remove
const struct file_operations *debugfs_real_fops(const struct file *filp);
int debugfs_file_get(struct dentry *dentry);
void debugfs_file_put(struct dentry *dentry);
ssize_t debugfs_attr_read(struct file *file, char __user *buf,
size_t len, loff_t *ppos);
ssize_t debugfs_attr_write(struct file *file, const char __user *buf,
size_t len, loff_t *ppos);
struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
struct dentry *new_dir, const char *new_name);
void debugfs_create_u8(const char *name, umode_t mode, struct dentry *parent,
u8 *value);
void debugfs_create_u16(const char *name, umode_t mode, struct dentry *parent,
u16 *value);
void debugfs_create_u32(const char *name, umode_t mode, struct dentry *parent,
u32 *value);
void debugfs_create_u64(const char *name, umode_t mode, struct dentry *parent,
u64 *value);
void debugfs_create_ulong(const char *name, umode_t mode, struct dentry *parent,
unsigned long *value);
void debugfs_create_x8(const char *name, umode_t mode, struct dentry *parent,
u8 *value);
void debugfs_create_x16(const char *name, umode_t mode, struct dentry *parent,
u16 *value);
void debugfs_create_x32(const char *name, umode_t mode, struct dentry *parent,
u32 *value);
void debugfs_create_x64(const char *name, umode_t mode, struct dentry *parent,
u64 *value);
void debugfs_create_size_t(const char *name, umode_t mode,
struct dentry *parent, size_t *value);
void debugfs_create_atomic_t(const char *name, umode_t mode,
struct dentry *parent, atomic_t *value);
void debugfs_create_bool(const char *name, umode_t mode, struct dentry *parent,
bool *value);
void debugfs_create_str(const char *name, umode_t mode,
struct dentry *parent, char **value);
struct dentry *debugfs_create_blob(const char *name, umode_t mode,
struct dentry *parent,
struct debugfs_blob_wrapper *blob);
void debugfs_create_regset32(const char *name, umode_t mode,
struct dentry *parent,
struct debugfs_regset32 *regset);
void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
int nregs, void __iomem *base, char *prefix);
void debugfs_create_u32_array(const char *name, umode_t mode,
struct dentry *parent,
struct debugfs_u32_array *array);
void debugfs_create_devm_seqfile(struct device *dev, const char *name,
struct dentry *parent,
int (*read_fn)(struct seq_file *s, void *data));
bool debugfs_initialized(void);
ssize_t debugfs_read_file_bool(struct file *file, char __user *user_buf,
size_t count, loff_t *ppos);
ssize_t debugfs_write_file_bool(struct file *file, const char __user *user_buf,
size_t count, loff_t *ppos);
ssize_t debugfs_read_file_str(struct file *file, char __user *user_buf,
size_t count, loff_t *ppos);
#else
#include <linux/err.h>
/*
* We do not return NULL from these functions if CONFIG_DEBUG_FS is not enabled
* so users have a chance to detect if there was a real error or not. We don't
* want to duplicate the design decision mistakes of procfs and devfs again.
*/
static inline struct dentry *debugfs_lookup(const char *name,
struct dentry *parent)
{
return ERR_PTR(-ENODEV);
}
static inline struct dentry *debugfs_create_file(const char *name, umode_t mode,
struct dentry *parent, void *data,
const struct file_operations *fops)
{
return ERR_PTR(-ENODEV);
}
static inline struct dentry *debugfs_create_file_unsafe(const char *name,
umode_t mode, struct dentry *parent,
void *data,
const struct file_operations *fops)
{
return ERR_PTR(-ENODEV);
}
static inline void debugfs_create_file_size(const char *name, umode_t mode,
struct dentry *parent, void *data,
const struct file_operations *fops,
loff_t file_size)
{ }
static inline struct dentry *debugfs_create_dir(const char *name,
struct dentry *parent)
{
return ERR_PTR(-ENODEV);
}
static inline struct dentry *debugfs_create_symlink(const char *name,
struct dentry *parent,
const char *dest)
{
return ERR_PTR(-ENODEV);
}
static inline struct dentry *debugfs_create_automount(const char *name,
struct dentry *parent,
debugfs_automount_t f,
void *data)
{
return ERR_PTR(-ENODEV);
}
static inline void debugfs_remove(struct dentry *dentry)
{ }
static inline void debugfs_remove_recursive(struct dentry *dentry)
{ }
const struct file_operations *debugfs_real_fops(const struct file *filp);
static inline int debugfs_file_get(struct dentry *dentry)
{
return 0;
}
static inline void debugfs_file_put(struct dentry *dentry)
{ }
static inline ssize_t debugfs_attr_read(struct file *file, char __user *buf,
size_t len, loff_t *ppos)
{
return -ENODEV;
}
static inline ssize_t debugfs_attr_write(struct file *file,
const char __user *buf,
size_t len, loff_t *ppos)
{
return -ENODEV;
}
static inline struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
struct dentry *new_dir, char *new_name)
{
return ERR_PTR(-ENODEV);
}
static inline void debugfs_create_u8(const char *name, umode_t mode,
struct dentry *parent, u8 *value) { }
static inline void debugfs_create_u16(const char *name, umode_t mode,
struct dentry *parent, u16 *value) { }
static inline void debugfs_create_u32(const char *name, umode_t mode,
struct dentry *parent, u32 *value) { }
static inline void debugfs_create_u64(const char *name, umode_t mode,
struct dentry *parent, u64 *value) { }
static inline void debugfs_create_ulong(const char *name, umode_t mode,
struct dentry *parent,
unsigned long *value) { }
static inline void debugfs_create_x8(const char *name, umode_t mode,
struct dentry *parent, u8 *value) { }
static inline void debugfs_create_x16(const char *name, umode_t mode,
struct dentry *parent, u16 *value) { }
static inline void debugfs_create_x32(const char *name, umode_t mode,
struct dentry *parent, u32 *value) { }
static inline void debugfs_create_x64(const char *name, umode_t mode,
struct dentry *parent, u64 *value) { }
static inline void debugfs_create_size_t(const char *name, umode_t mode,
struct dentry *parent, size_t *value)
{ }
static inline void debugfs_create_atomic_t(const char *name, umode_t mode,
struct dentry *parent,
atomic_t *value)
{ }
static inline void debugfs_create_bool(const char *name, umode_t mode,
struct dentry *parent, bool *value) { }
static inline void debugfs_create_str(const char *name, umode_t mode,
struct dentry *parent,
char **value)
{ }
static inline struct dentry *debugfs_create_blob(const char *name, umode_t mode,
struct dentry *parent,
struct debugfs_blob_wrapper *blob)
{
return ERR_PTR(-ENODEV);
}
static inline void debugfs_create_regset32(const char *name, umode_t mode,
struct dentry *parent,
struct debugfs_regset32 *regset)
{
}
static inline void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
int nregs, void __iomem *base, char *prefix)
{
}
static inline bool debugfs_initialized(void)
{
return false;
}
static inline void debugfs_create_u32_array(const char *name, umode_t mode,
struct dentry *parent,
struct debugfs_u32_array *array)
{
}
static inline void debugfs_create_devm_seqfile(struct device *dev,
const char *name,
struct dentry *parent,
int (*read_fn)(struct seq_file *s,
void *data))
{
}
static inline ssize_t debugfs_read_file_bool(struct file *file,
char __user *user_buf,
size_t count, loff_t *ppos)
{
return -ENODEV;
}
static inline ssize_t debugfs_write_file_bool(struct file *file,
const char __user *user_buf,
size_t count, loff_t *ppos)
{
return -ENODEV;
}
static inline ssize_t debugfs_read_file_str(struct file *file,
char __user *user_buf,
size_t count, loff_t *ppos)
{
return -ENODEV;
}
#endif
/**
* debugfs_create_xul - create a debugfs file that is used to read and write an
* unsigned long value, formatted in hexadecimal
* @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.
*/
static inline void debugfs_create_xul(const char *name, umode_t mode,
struct dentry *parent,
unsigned long *value)
{
if (sizeof(*value) == sizeof(u32))
debugfs_create_x32(name, mode, parent, (u32 *)value);
else
debugfs_create_x64(name, mode, parent, (u64 *)value);
}
#endif