alistair23-linux/include/linux/debugfs.h
Frederic Weisbecker c0f92ba99b debugfs: function to know if debugfs is initialized
Impact: add new debugfs API

With ftrace, some tracers are registered in early initcalls
and attempt to create files on the debugfs filesystem.
Depending on when they are activated, they can try to create their
file at any time. Some checks can be done on the tracing area
but providing a helper to know if debugfs is registered make it
really more easy.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <1237759847-21025-2-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-23 16:25:46 +01:00

197 lines
5.2 KiB
C

/*
* debugfs.h - 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/kernel-api for more details.
*/
#ifndef _DEBUGFS_H_
#define _DEBUGFS_H_
#include <linux/fs.h>
#include <linux/types.h>
struct file_operations;
struct debugfs_blob_wrapper {
void *data;
unsigned long size;
};
extern struct dentry *arch_debugfs_dir;
#if defined(CONFIG_DEBUG_FS)
/* declared over in file.c */
extern const struct file_operations debugfs_file_operations;
extern const struct inode_operations debugfs_link_operations;
struct dentry *debugfs_create_file(const char *name, mode_t mode,
struct dentry *parent, void *data,
const struct file_operations *fops);
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);
void debugfs_remove(struct dentry *dentry);
void debugfs_remove_recursive(struct dentry *dentry);
struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
struct dentry *new_dir, const char *new_name);
struct dentry *debugfs_create_u8(const char *name, mode_t mode,
struct dentry *parent, u8 *value);
struct dentry *debugfs_create_u16(const char *name, mode_t mode,
struct dentry *parent, u16 *value);
struct dentry *debugfs_create_u32(const char *name, mode_t mode,
struct dentry *parent, u32 *value);
struct dentry *debugfs_create_u64(const char *name, mode_t mode,
struct dentry *parent, u64 *value);
struct dentry *debugfs_create_x8(const char *name, mode_t mode,
struct dentry *parent, u8 *value);
struct dentry *debugfs_create_x16(const char *name, mode_t mode,
struct dentry *parent, u16 *value);
struct dentry *debugfs_create_x32(const char *name, mode_t mode,
struct dentry *parent, u32 *value);
struct dentry *debugfs_create_size_t(const char *name, mode_t mode,
struct dentry *parent, size_t *value);
struct dentry *debugfs_create_bool(const char *name, mode_t mode,
struct dentry *parent, u32 *value);
struct dentry *debugfs_create_blob(const char *name, mode_t mode,
struct dentry *parent,
struct debugfs_blob_wrapper *blob);
bool debugfs_initialized(void);
#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_create_file(const char *name, mode_t mode,
struct dentry *parent, void *data,
const struct file_operations *fops)
{
return ERR_PTR(-ENODEV);
}
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 void debugfs_remove(struct dentry *dentry)
{ }
static inline void debugfs_remove_recursive(struct dentry *dentry)
{ }
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 struct dentry *debugfs_create_u8(const char *name, mode_t mode,
struct dentry *parent,
u8 *value)
{
return ERR_PTR(-ENODEV);
}
static inline struct dentry *debugfs_create_u16(const char *name, mode_t mode,
struct dentry *parent,
u16 *value)
{
return ERR_PTR(-ENODEV);
}
static inline struct dentry *debugfs_create_u32(const char *name, mode_t mode,
struct dentry *parent,
u32 *value)
{
return ERR_PTR(-ENODEV);
}
static inline struct dentry *debugfs_create_u64(const char *name, mode_t mode,
struct dentry *parent,
u64 *value)
{
return ERR_PTR(-ENODEV);
}
static inline struct dentry *debugfs_create_x8(const char *name, mode_t mode,
struct dentry *parent,
u8 *value)
{
return ERR_PTR(-ENODEV);
}
static inline struct dentry *debugfs_create_x16(const char *name, mode_t mode,
struct dentry *parent,
u16 *value)
{
return ERR_PTR(-ENODEV);
}
static inline struct dentry *debugfs_create_x32(const char *name, mode_t mode,
struct dentry *parent,
u32 *value)
{
return ERR_PTR(-ENODEV);
}
static inline struct dentry *debugfs_create_size_t(const char *name, mode_t mode,
struct dentry *parent,
size_t *value)
{
return ERR_PTR(-ENODEV);
}
static inline struct dentry *debugfs_create_bool(const char *name, mode_t mode,
struct dentry *parent,
u32 *value)
{
return ERR_PTR(-ENODEV);
}
static inline struct dentry *debugfs_create_blob(const char *name, mode_t mode,
struct dentry *parent,
struct debugfs_blob_wrapper *blob)
{
return ERR_PTR(-ENODEV);
}
static inline bool debugfs_initialized(void)
{
return false;
}
#endif
#endif