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 #if defined(CONFIG_DEBUG_FS)
67 struct dentry *debugfs_create_file(const char *name, umode_t mode,
68 struct dentry *parent, void *data,
69 const struct file_operations *fops);
70 struct dentry *debugfs_create_file_unsafe(const char *name, umode_t mode,
71 struct dentry *parent, void *data,
72 const struct file_operations *fops);
74 struct dentry *debugfs_create_file_size(const char *name, umode_t mode,
75 struct dentry *parent, void *data,
76 const struct file_operations *fops,
79 struct dentry *debugfs_create_dir(const char *name, struct dentry *parent);
81 struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent,
84 struct dentry *debugfs_create_automount(const char *name,
85 struct dentry *parent,
86 struct vfsmount *(*f)(void *),
89 void debugfs_remove(struct dentry *dentry);
90 void debugfs_remove_recursive(struct dentry *dentry);
92 int debugfs_use_file_start(const struct dentry *dentry, int *srcu_idx)
93 __acquires(&debugfs_srcu);
95 void debugfs_use_file_finish(int srcu_idx) __releases(&debugfs_srcu);
97 ssize_t debugfs_attr_read(struct file *file, char __user *buf,
98 size_t len, loff_t *ppos);
99 ssize_t debugfs_attr_write(struct file *file, const char __user *buf,
100 size_t len, loff_t *ppos);
102 #define DEFINE_DEBUGFS_ATTRIBUTE(__fops, __get, __set, __fmt) \
103 static int __fops ## _open(struct inode *inode, struct file *file) \
105 __simple_attr_check_format(__fmt, 0ull); \
106 return simple_attr_open(inode, file, __get, __set, __fmt); \
108 static const struct file_operations __fops = { \
109 .owner = THIS_MODULE, \
110 .open = __fops ## _open, \
111 .release = simple_attr_release, \
112 .read = debugfs_attr_read, \
113 .write = debugfs_attr_write, \
114 .llseek = generic_file_llseek, \
117 struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
118 struct dentry *new_dir, const char *new_name);
120 struct dentry *debugfs_create_u8(const char *name, umode_t mode,
121 struct dentry *parent, u8 *value);
122 struct dentry *debugfs_create_u16(const char *name, umode_t mode,
123 struct dentry *parent, u16 *value);
124 struct dentry *debugfs_create_u32(const char *name, umode_t mode,
125 struct dentry *parent, u32 *value);
126 struct dentry *debugfs_create_u64(const char *name, umode_t mode,
127 struct dentry *parent, u64 *value);
128 struct dentry *debugfs_create_ulong(const char *name, umode_t mode,
129 struct dentry *parent, unsigned long *value);
130 struct dentry *debugfs_create_x8(const char *name, umode_t mode,
131 struct dentry *parent, u8 *value);
132 struct dentry *debugfs_create_x16(const char *name, umode_t mode,
133 struct dentry *parent, u16 *value);
134 struct dentry *debugfs_create_x32(const char *name, umode_t mode,
135 struct dentry *parent, u32 *value);
136 struct dentry *debugfs_create_x64(const char *name, umode_t mode,
137 struct dentry *parent, u64 *value);
138 struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
139 struct dentry *parent, size_t *value);
140 struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
141 struct dentry *parent, atomic_t *value);
142 struct dentry *debugfs_create_bool(const char *name, umode_t mode,
143 struct dentry *parent, bool *value);
145 struct dentry *debugfs_create_blob(const char *name, umode_t mode,
146 struct dentry *parent,
147 struct debugfs_blob_wrapper *blob);
149 struct dentry *debugfs_create_regset32(const char *name, umode_t mode,
150 struct dentry *parent,
151 struct debugfs_regset32 *regset);
153 void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
154 int nregs, void __iomem *base, char *prefix);
156 struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
157 struct dentry *parent,
158 u32 *array, u32 elements);
160 struct dentry *debugfs_create_devm_seqfile(struct device *dev, const char *name,
161 struct dentry *parent,
162 int (*read_fn)(struct seq_file *s,
165 bool debugfs_initialized(void);
167 ssize_t debugfs_read_file_bool(struct file *file, char __user *user_buf,
168 size_t count, loff_t *ppos);
170 ssize_t debugfs_write_file_bool(struct file *file, const char __user *user_buf,
171 size_t count, loff_t *ppos);
175 #include <linux/err.h>
178 * We do not return NULL from these functions if CONFIG_DEBUG_FS is not enabled
179 * so users have a chance to detect if there was a real error or not. We don't
180 * want to duplicate the design decision mistakes of procfs and devfs again.
183 static inline struct dentry *debugfs_create_file(const char *name, umode_t mode,
184 struct dentry *parent, void *data,
185 const struct file_operations *fops)
187 return ERR_PTR(-ENODEV);
190 static inline struct dentry *debugfs_create_file_size(const char *name, umode_t mode,
191 struct dentry *parent, void *data,
192 const struct file_operations *fops,
195 return ERR_PTR(-ENODEV);
198 static inline struct dentry *debugfs_create_dir(const char *name,
199 struct dentry *parent)
201 return ERR_PTR(-ENODEV);
204 static inline struct dentry *debugfs_create_symlink(const char *name,
205 struct dentry *parent,
208 return ERR_PTR(-ENODEV);
211 static inline struct dentry *debugfs_create_automount(const char *name,
212 struct dentry *parent,
213 struct vfsmount *(*f)(void *),
216 return ERR_PTR(-ENODEV);
219 static inline void debugfs_remove(struct dentry *dentry)
222 static inline void debugfs_remove_recursive(struct dentry *dentry)
225 static inline int debugfs_use_file_start(const struct dentry *dentry,
227 __acquires(&debugfs_srcu)
232 static inline void debugfs_use_file_finish(int srcu_idx)
233 __releases(&debugfs_srcu)
236 #define DEFINE_DEBUGFS_ATTRIBUTE(__fops, __get, __set, __fmt) \
237 static const struct file_operations __fops = { 0 }
239 static inline struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
240 struct dentry *new_dir, char *new_name)
242 return ERR_PTR(-ENODEV);
245 static inline struct dentry *debugfs_create_u8(const char *name, umode_t mode,
246 struct dentry *parent,
249 return ERR_PTR(-ENODEV);
252 static inline struct dentry *debugfs_create_u16(const char *name, umode_t mode,
253 struct dentry *parent,
256 return ERR_PTR(-ENODEV);
259 static inline struct dentry *debugfs_create_u32(const char *name, umode_t mode,
260 struct dentry *parent,
263 return ERR_PTR(-ENODEV);
266 static inline struct dentry *debugfs_create_u64(const char *name, umode_t mode,
267 struct dentry *parent,
270 return ERR_PTR(-ENODEV);
273 static inline struct dentry *debugfs_create_x8(const char *name, umode_t mode,
274 struct dentry *parent,
277 return ERR_PTR(-ENODEV);
280 static inline struct dentry *debugfs_create_x16(const char *name, umode_t mode,
281 struct dentry *parent,
284 return ERR_PTR(-ENODEV);
287 static inline struct dentry *debugfs_create_x32(const char *name, umode_t mode,
288 struct dentry *parent,
291 return ERR_PTR(-ENODEV);
294 static inline struct dentry *debugfs_create_x64(const char *name, umode_t mode,
295 struct dentry *parent,
298 return ERR_PTR(-ENODEV);
301 static inline struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
302 struct dentry *parent,
305 return ERR_PTR(-ENODEV);
308 static inline struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
309 struct dentry *parent, atomic_t *value)
311 return ERR_PTR(-ENODEV);
314 static inline struct dentry *debugfs_create_bool(const char *name, umode_t mode,
315 struct dentry *parent,
318 return ERR_PTR(-ENODEV);
321 static inline struct dentry *debugfs_create_blob(const char *name, umode_t mode,
322 struct dentry *parent,
323 struct debugfs_blob_wrapper *blob)
325 return ERR_PTR(-ENODEV);
328 static inline struct dentry *debugfs_create_regset32(const char *name,
329 umode_t mode, struct dentry *parent,
330 struct debugfs_regset32 *regset)
332 return ERR_PTR(-ENODEV);
335 static inline void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
336 int nregs, void __iomem *base, char *prefix)
340 static inline bool debugfs_initialized(void)
345 static inline struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
346 struct dentry *parent,
347 u32 *array, u32 elements)
349 return ERR_PTR(-ENODEV);
352 static inline struct dentry *debugfs_create_devm_seqfile(struct device *dev,
354 struct dentry *parent,
355 int (*read_fn)(struct seq_file *s,
358 return ERR_PTR(-ENODEV);
361 static inline ssize_t debugfs_read_file_bool(struct file *file,
362 char __user *user_buf,
363 size_t count, loff_t *ppos)
368 static inline ssize_t debugfs_write_file_bool(struct file *file,
369 const char __user *user_buf,
370 size_t count, loff_t *ppos)