2 * debugfs.h - a tiny little debug file system
4 * Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
5 * Copyright (C) 2004 IBM Inc.
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License version
9 * 2 as published by the Free Software Foundation.
11 * debugfs is for people to use instead of /proc or /sys.
12 * See Documentation/DocBook/filesystems for more details.
19 #include <linux/seq_file.h>
21 #include <linux/types.h>
22 #include <linux/compiler.h>
25 struct file_operations;
28 struct debugfs_blob_wrapper {
33 struct debugfs_reg32 {
38 struct debugfs_regset32 {
39 const struct debugfs_reg32 *regs;
44 extern struct dentry *arch_debugfs_dir;
46 extern struct srcu_struct debugfs_srcu;
49 * debugfs_real_fops - getter for the real file operation
50 * @filp: a pointer to a struct file
52 * Must only be called under the protection established by
53 * debugfs_use_file_start().
55 static inline const struct file_operations *debugfs_real_fops(struct file *filp)
56 __must_hold(&debugfs_srcu)
59 * Neither the pointer to the struct file_operations, nor its
60 * contents ever change -- srcu_dereference() is not needed here.
62 return filp->f_path.dentry->d_fsdata;
65 #define DEFINE_DEBUGFS_ATTRIBUTE(__fops, __get, __set, __fmt) \
66 static int __fops ## _open(struct inode *inode, struct file *file) \
68 __simple_attr_check_format(__fmt, 0ull); \
69 return simple_attr_open(inode, file, __get, __set, __fmt); \
71 static const struct file_operations __fops = { \
72 .owner = THIS_MODULE, \
73 .open = __fops ## _open, \
74 .release = simple_attr_release, \
75 .read = debugfs_attr_read, \
76 .write = debugfs_attr_write, \
77 .llseek = generic_file_llseek, \
80 typedef struct vfsmount *(*debugfs_automount_t)(struct dentry *, void *);
82 #if defined(CONFIG_DEBUG_FS)
84 struct dentry *debugfs_create_file(const char *name, umode_t mode,
85 struct dentry *parent, void *data,
86 const struct file_operations *fops);
87 struct dentry *debugfs_create_file_unsafe(const char *name, umode_t mode,
88 struct dentry *parent, void *data,
89 const struct file_operations *fops);
91 struct dentry *debugfs_create_file_size(const char *name, umode_t mode,
92 struct dentry *parent, void *data,
93 const struct file_operations *fops,
96 struct dentry *debugfs_create_dir(const char *name, struct dentry *parent);
98 struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent,
101 struct dentry *debugfs_create_automount(const char *name,
102 struct dentry *parent,
103 debugfs_automount_t f,
106 void debugfs_remove(struct dentry *dentry);
107 void debugfs_remove_recursive(struct dentry *dentry);
109 int debugfs_use_file_start(const struct dentry *dentry, int *srcu_idx)
110 __acquires(&debugfs_srcu);
112 void debugfs_use_file_finish(int srcu_idx) __releases(&debugfs_srcu);
114 ssize_t debugfs_attr_read(struct file *file, char __user *buf,
115 size_t len, loff_t *ppos);
116 ssize_t debugfs_attr_write(struct file *file, const char __user *buf,
117 size_t len, loff_t *ppos);
119 struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
120 struct dentry *new_dir, const char *new_name);
122 struct dentry *debugfs_create_u8(const char *name, umode_t mode,
123 struct dentry *parent, u8 *value);
124 struct dentry *debugfs_create_u16(const char *name, umode_t mode,
125 struct dentry *parent, u16 *value);
126 struct dentry *debugfs_create_u32(const char *name, umode_t mode,
127 struct dentry *parent, u32 *value);
128 struct dentry *debugfs_create_u64(const char *name, umode_t mode,
129 struct dentry *parent, u64 *value);
130 struct dentry *debugfs_create_ulong(const char *name, umode_t mode,
131 struct dentry *parent, unsigned long *value);
132 struct dentry *debugfs_create_x8(const char *name, umode_t mode,
133 struct dentry *parent, u8 *value);
134 struct dentry *debugfs_create_x16(const char *name, umode_t mode,
135 struct dentry *parent, u16 *value);
136 struct dentry *debugfs_create_x32(const char *name, umode_t mode,
137 struct dentry *parent, u32 *value);
138 struct dentry *debugfs_create_x64(const char *name, umode_t mode,
139 struct dentry *parent, u64 *value);
140 struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
141 struct dentry *parent, size_t *value);
142 struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
143 struct dentry *parent, atomic_t *value);
144 struct dentry *debugfs_create_bool(const char *name, umode_t mode,
145 struct dentry *parent, bool *value);
147 struct dentry *debugfs_create_blob(const char *name, umode_t mode,
148 struct dentry *parent,
149 struct debugfs_blob_wrapper *blob);
151 struct dentry *debugfs_create_regset32(const char *name, umode_t mode,
152 struct dentry *parent,
153 struct debugfs_regset32 *regset);
155 void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
156 int nregs, void __iomem *base, char *prefix);
158 struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
159 struct dentry *parent,
160 u32 *array, u32 elements);
162 struct dentry *debugfs_create_devm_seqfile(struct device *dev, const char *name,
163 struct dentry *parent,
164 int (*read_fn)(struct seq_file *s,
167 bool debugfs_initialized(void);
169 ssize_t debugfs_read_file_bool(struct file *file, char __user *user_buf,
170 size_t count, loff_t *ppos);
172 ssize_t debugfs_write_file_bool(struct file *file, const char __user *user_buf,
173 size_t count, loff_t *ppos);
177 #include <linux/err.h>
180 * We do not return NULL from these functions if CONFIG_DEBUG_FS is not enabled
181 * so users have a chance to detect if there was a real error or not. We don't
182 * want to duplicate the design decision mistakes of procfs and devfs again.
185 static inline struct dentry *debugfs_create_file(const char *name, umode_t mode,
186 struct dentry *parent, void *data,
187 const struct file_operations *fops)
189 return ERR_PTR(-ENODEV);
192 static inline struct dentry *debugfs_create_file_size(const char *name, umode_t mode,
193 struct dentry *parent, void *data,
194 const struct file_operations *fops,
197 return ERR_PTR(-ENODEV);
200 static inline struct dentry *debugfs_create_dir(const char *name,
201 struct dentry *parent)
203 return ERR_PTR(-ENODEV);
206 static inline struct dentry *debugfs_create_symlink(const char *name,
207 struct dentry *parent,
210 return ERR_PTR(-ENODEV);
213 static inline struct dentry *debugfs_create_automount(const char *name,
214 struct dentry *parent,
215 debugfs_automount_t f,
218 return ERR_PTR(-ENODEV);
221 static inline void debugfs_remove(struct dentry *dentry)
224 static inline void debugfs_remove_recursive(struct dentry *dentry)
227 static inline int debugfs_use_file_start(const struct dentry *dentry,
229 __acquires(&debugfs_srcu)
234 static inline void debugfs_use_file_finish(int srcu_idx)
235 __releases(&debugfs_srcu)
238 static inline ssize_t debugfs_attr_read(struct file *file, char __user *buf,
239 size_t len, loff_t *ppos)
244 static inline ssize_t debugfs_attr_write(struct file *file,
245 const char __user *buf,
246 size_t len, loff_t *ppos)
251 static inline struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
252 struct dentry *new_dir, char *new_name)
254 return ERR_PTR(-ENODEV);
257 static inline struct dentry *debugfs_create_u8(const char *name, umode_t mode,
258 struct dentry *parent,
261 return ERR_PTR(-ENODEV);
264 static inline struct dentry *debugfs_create_u16(const char *name, umode_t mode,
265 struct dentry *parent,
268 return ERR_PTR(-ENODEV);
271 static inline struct dentry *debugfs_create_u32(const char *name, umode_t mode,
272 struct dentry *parent,
275 return ERR_PTR(-ENODEV);
278 static inline struct dentry *debugfs_create_u64(const char *name, umode_t mode,
279 struct dentry *parent,
282 return ERR_PTR(-ENODEV);
285 static inline struct dentry *debugfs_create_x8(const char *name, umode_t mode,
286 struct dentry *parent,
289 return ERR_PTR(-ENODEV);
292 static inline struct dentry *debugfs_create_x16(const char *name, umode_t mode,
293 struct dentry *parent,
296 return ERR_PTR(-ENODEV);
299 static inline struct dentry *debugfs_create_x32(const char *name, umode_t mode,
300 struct dentry *parent,
303 return ERR_PTR(-ENODEV);
306 static inline struct dentry *debugfs_create_x64(const char *name, umode_t mode,
307 struct dentry *parent,
310 return ERR_PTR(-ENODEV);
313 static inline struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
314 struct dentry *parent,
317 return ERR_PTR(-ENODEV);
320 static inline struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
321 struct dentry *parent, atomic_t *value)
323 return ERR_PTR(-ENODEV);
326 static inline struct dentry *debugfs_create_bool(const char *name, umode_t mode,
327 struct dentry *parent,
330 return ERR_PTR(-ENODEV);
333 static inline struct dentry *debugfs_create_blob(const char *name, umode_t mode,
334 struct dentry *parent,
335 struct debugfs_blob_wrapper *blob)
337 return ERR_PTR(-ENODEV);
340 static inline struct dentry *debugfs_create_regset32(const char *name,
341 umode_t mode, struct dentry *parent,
342 struct debugfs_regset32 *regset)
344 return ERR_PTR(-ENODEV);
347 static inline void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
348 int nregs, void __iomem *base, char *prefix)
352 static inline bool debugfs_initialized(void)
357 static inline struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
358 struct dentry *parent,
359 u32 *array, u32 elements)
361 return ERR_PTR(-ENODEV);
364 static inline struct dentry *debugfs_create_devm_seqfile(struct device *dev,
366 struct dentry *parent,
367 int (*read_fn)(struct seq_file *s,
370 return ERR_PTR(-ENODEV);
373 static inline ssize_t debugfs_read_file_bool(struct file *file,
374 char __user *user_buf,
375 size_t count, loff_t *ppos)
380 static inline ssize_t debugfs_write_file_bool(struct file *file,
381 const char __user *user_buf,
382 size_t count, loff_t *ppos)