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 *
56 debugfs_real_fops(const struct file *filp)
57 __must_hold(&debugfs_srcu)
60 * Neither the pointer to the struct file_operations, nor its
61 * contents ever change -- srcu_dereference() is not needed here.
63 return filp->f_path.dentry->d_fsdata;
66 #if defined(CONFIG_DEBUG_FS)
68 struct dentry *debugfs_create_file(const char *name, umode_t mode,
69 struct dentry *parent, void *data,
70 const struct file_operations *fops);
71 struct dentry *debugfs_create_file_unsafe(const char *name, umode_t mode,
72 struct dentry *parent, void *data,
73 const struct file_operations *fops);
75 struct dentry *debugfs_create_file_size(const char *name, umode_t mode,
76 struct dentry *parent, void *data,
77 const struct file_operations *fops,
80 struct dentry *debugfs_create_dir(const char *name, struct dentry *parent);
82 struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent,
85 struct dentry *debugfs_create_automount(const char *name,
86 struct dentry *parent,
87 struct vfsmount *(*f)(void *),
90 void debugfs_remove(struct dentry *dentry);
91 void debugfs_remove_recursive(struct dentry *dentry);
93 int debugfs_use_file_start(const struct dentry *dentry, int *srcu_idx)
94 __acquires(&debugfs_srcu);
96 void debugfs_use_file_finish(int srcu_idx) __releases(&debugfs_srcu);
98 ssize_t debugfs_attr_read(struct file *file, char __user *buf,
99 size_t len, loff_t *ppos);
100 ssize_t debugfs_attr_write(struct file *file, const char __user *buf,
101 size_t len, loff_t *ppos);
103 #define DEFINE_DEBUGFS_ATTRIBUTE(__fops, __get, __set, __fmt) \
104 static int __fops ## _open(struct inode *inode, struct file *file) \
106 __simple_attr_check_format(__fmt, 0ull); \
107 return simple_attr_open(inode, file, __get, __set, __fmt); \
109 static const struct file_operations __fops = { \
110 .owner = THIS_MODULE, \
111 .open = __fops ## _open, \
112 .release = simple_attr_release, \
113 .read = debugfs_attr_read, \
114 .write = debugfs_attr_write, \
115 .llseek = generic_file_llseek, \
118 struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
119 struct dentry *new_dir, const char *new_name);
121 struct dentry *debugfs_create_u8(const char *name, umode_t mode,
122 struct dentry *parent, u8 *value);
123 struct dentry *debugfs_create_u16(const char *name, umode_t mode,
124 struct dentry *parent, u16 *value);
125 struct dentry *debugfs_create_u32(const char *name, umode_t mode,
126 struct dentry *parent, u32 *value);
127 struct dentry *debugfs_create_u64(const char *name, umode_t mode,
128 struct dentry *parent, u64 *value);
129 struct dentry *debugfs_create_ulong(const char *name, umode_t mode,
130 struct dentry *parent, unsigned long *value);
131 struct dentry *debugfs_create_x8(const char *name, umode_t mode,
132 struct dentry *parent, u8 *value);
133 struct dentry *debugfs_create_x16(const char *name, umode_t mode,
134 struct dentry *parent, u16 *value);
135 struct dentry *debugfs_create_x32(const char *name, umode_t mode,
136 struct dentry *parent, u32 *value);
137 struct dentry *debugfs_create_x64(const char *name, umode_t mode,
138 struct dentry *parent, u64 *value);
139 struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
140 struct dentry *parent, size_t *value);
141 struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
142 struct dentry *parent, atomic_t *value);
143 struct dentry *debugfs_create_bool(const char *name, umode_t mode,
144 struct dentry *parent, bool *value);
146 struct dentry *debugfs_create_blob(const char *name, umode_t mode,
147 struct dentry *parent,
148 struct debugfs_blob_wrapper *blob);
150 struct dentry *debugfs_create_regset32(const char *name, umode_t mode,
151 struct dentry *parent,
152 struct debugfs_regset32 *regset);
154 void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
155 int nregs, void __iomem *base, char *prefix);
157 struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
158 struct dentry *parent,
159 u32 *array, u32 elements);
161 struct dentry *debugfs_create_devm_seqfile(struct device *dev, const char *name,
162 struct dentry *parent,
163 int (*read_fn)(struct seq_file *s,
166 bool debugfs_initialized(void);
168 ssize_t debugfs_read_file_bool(struct file *file, char __user *user_buf,
169 size_t count, loff_t *ppos);
171 ssize_t debugfs_write_file_bool(struct file *file, const char __user *user_buf,
172 size_t count, loff_t *ppos);
176 #include <linux/err.h>
179 * We do not return NULL from these functions if CONFIG_DEBUG_FS is not enabled
180 * so users have a chance to detect if there was a real error or not. We don't
181 * want to duplicate the design decision mistakes of procfs and devfs again.
184 static inline struct dentry *debugfs_create_file(const char *name, umode_t mode,
185 struct dentry *parent, void *data,
186 const struct file_operations *fops)
188 return ERR_PTR(-ENODEV);
191 static inline struct dentry *debugfs_create_file_size(const char *name, umode_t mode,
192 struct dentry *parent, void *data,
193 const struct file_operations *fops,
196 return ERR_PTR(-ENODEV);
199 static inline struct dentry *debugfs_create_dir(const char *name,
200 struct dentry *parent)
202 return ERR_PTR(-ENODEV);
205 static inline struct dentry *debugfs_create_symlink(const char *name,
206 struct dentry *parent,
209 return ERR_PTR(-ENODEV);
212 static inline struct dentry *debugfs_create_automount(const char *name,
213 struct dentry *parent,
214 struct vfsmount *(*f)(void *),
217 return ERR_PTR(-ENODEV);
220 static inline void debugfs_remove(struct dentry *dentry)
223 static inline void debugfs_remove_recursive(struct dentry *dentry)
226 static inline int debugfs_use_file_start(const struct dentry *dentry,
228 __acquires(&debugfs_srcu)
233 static inline void debugfs_use_file_finish(int srcu_idx)
234 __releases(&debugfs_srcu)
237 #define DEFINE_DEBUGFS_ATTRIBUTE(__fops, __get, __set, __fmt) \
238 static const struct file_operations __fops = { 0 }
240 static inline struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
241 struct dentry *new_dir, char *new_name)
243 return ERR_PTR(-ENODEV);
246 static inline struct dentry *debugfs_create_u8(const char *name, umode_t mode,
247 struct dentry *parent,
250 return ERR_PTR(-ENODEV);
253 static inline struct dentry *debugfs_create_u16(const char *name, umode_t mode,
254 struct dentry *parent,
257 return ERR_PTR(-ENODEV);
260 static inline struct dentry *debugfs_create_u32(const char *name, umode_t mode,
261 struct dentry *parent,
264 return ERR_PTR(-ENODEV);
267 static inline struct dentry *debugfs_create_u64(const char *name, umode_t mode,
268 struct dentry *parent,
271 return ERR_PTR(-ENODEV);
274 static inline struct dentry *debugfs_create_x8(const char *name, umode_t mode,
275 struct dentry *parent,
278 return ERR_PTR(-ENODEV);
281 static inline struct dentry *debugfs_create_x16(const char *name, umode_t mode,
282 struct dentry *parent,
285 return ERR_PTR(-ENODEV);
288 static inline struct dentry *debugfs_create_x32(const char *name, umode_t mode,
289 struct dentry *parent,
292 return ERR_PTR(-ENODEV);
295 static inline struct dentry *debugfs_create_x64(const char *name, umode_t mode,
296 struct dentry *parent,
299 return ERR_PTR(-ENODEV);
302 static inline struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
303 struct dentry *parent,
306 return ERR_PTR(-ENODEV);
309 static inline struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
310 struct dentry *parent, atomic_t *value)
312 return ERR_PTR(-ENODEV);
315 static inline struct dentry *debugfs_create_bool(const char *name, umode_t mode,
316 struct dentry *parent,
319 return ERR_PTR(-ENODEV);
322 static inline struct dentry *debugfs_create_blob(const char *name, umode_t mode,
323 struct dentry *parent,
324 struct debugfs_blob_wrapper *blob)
326 return ERR_PTR(-ENODEV);
329 static inline struct dentry *debugfs_create_regset32(const char *name,
330 umode_t mode, struct dentry *parent,
331 struct debugfs_regset32 *regset)
333 return ERR_PTR(-ENODEV);
336 static inline void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
337 int nregs, void __iomem *base, char *prefix)
341 static inline bool debugfs_initialized(void)
346 static inline struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
347 struct dentry *parent,
348 u32 *array, u32 elements)
350 return ERR_PTR(-ENODEV);
353 static inline struct dentry *debugfs_create_devm_seqfile(struct device *dev,
355 struct dentry *parent,
356 int (*read_fn)(struct seq_file *s,
359 return ERR_PTR(-ENODEV);
362 static inline ssize_t debugfs_read_file_bool(struct file *file,
363 char __user *user_buf,
364 size_t count, loff_t *ppos)
369 static inline ssize_t debugfs_write_file_bool(struct file *file,
370 const char __user *user_buf,
371 size_t count, loff_t *ppos)