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/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(const 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 = no_llseek, \
80 typedef struct vfsmount *(*debugfs_automount_t)(struct dentry *, void *);
82 #if defined(CONFIG_DEBUG_FS)
84 struct dentry *debugfs_lookup(const char *name, struct dentry *parent);
86 struct dentry *debugfs_create_file(const char *name, umode_t mode,
87 struct dentry *parent, void *data,
88 const struct file_operations *fops);
89 struct dentry *debugfs_create_file_unsafe(const char *name, umode_t mode,
90 struct dentry *parent, void *data,
91 const struct file_operations *fops);
93 struct dentry *debugfs_create_file_size(const char *name, umode_t mode,
94 struct dentry *parent, void *data,
95 const struct file_operations *fops,
98 struct dentry *debugfs_create_dir(const char *name, struct dentry *parent);
100 struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent,
103 struct dentry *debugfs_create_automount(const char *name,
104 struct dentry *parent,
105 debugfs_automount_t f,
108 void debugfs_remove(struct dentry *dentry);
109 void debugfs_remove_recursive(struct dentry *dentry);
111 int debugfs_use_file_start(const struct dentry *dentry, int *srcu_idx)
112 __acquires(&debugfs_srcu);
114 void debugfs_use_file_finish(int srcu_idx) __releases(&debugfs_srcu);
116 ssize_t debugfs_attr_read(struct file *file, char __user *buf,
117 size_t len, loff_t *ppos);
118 ssize_t debugfs_attr_write(struct file *file, const char __user *buf,
119 size_t len, loff_t *ppos);
121 struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
122 struct dentry *new_dir, const char *new_name);
124 struct dentry *debugfs_create_u8(const char *name, umode_t mode,
125 struct dentry *parent, u8 *value);
126 struct dentry *debugfs_create_u16(const char *name, umode_t mode,
127 struct dentry *parent, u16 *value);
128 struct dentry *debugfs_create_u32(const char *name, umode_t mode,
129 struct dentry *parent, u32 *value);
130 struct dentry *debugfs_create_u64(const char *name, umode_t mode,
131 struct dentry *parent, u64 *value);
132 struct dentry *debugfs_create_ulong(const char *name, umode_t mode,
133 struct dentry *parent, unsigned long *value);
134 struct dentry *debugfs_create_x8(const char *name, umode_t mode,
135 struct dentry *parent, u8 *value);
136 struct dentry *debugfs_create_x16(const char *name, umode_t mode,
137 struct dentry *parent, u16 *value);
138 struct dentry *debugfs_create_x32(const char *name, umode_t mode,
139 struct dentry *parent, u32 *value);
140 struct dentry *debugfs_create_x64(const char *name, umode_t mode,
141 struct dentry *parent, u64 *value);
142 struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
143 struct dentry *parent, size_t *value);
144 struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
145 struct dentry *parent, atomic_t *value);
146 struct dentry *debugfs_create_bool(const char *name, umode_t mode,
147 struct dentry *parent, bool *value);
149 struct dentry *debugfs_create_blob(const char *name, umode_t mode,
150 struct dentry *parent,
151 struct debugfs_blob_wrapper *blob);
153 struct dentry *debugfs_create_regset32(const char *name, umode_t mode,
154 struct dentry *parent,
155 struct debugfs_regset32 *regset);
157 void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
158 int nregs, void __iomem *base, char *prefix);
160 struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
161 struct dentry *parent,
162 u32 *array, u32 elements);
164 struct dentry *debugfs_create_devm_seqfile(struct device *dev, const char *name,
165 struct dentry *parent,
166 int (*read_fn)(struct seq_file *s,
169 bool debugfs_initialized(void);
171 ssize_t debugfs_read_file_bool(struct file *file, char __user *user_buf,
172 size_t count, loff_t *ppos);
174 ssize_t debugfs_write_file_bool(struct file *file, const char __user *user_buf,
175 size_t count, loff_t *ppos);
179 #include <linux/err.h>
182 * We do not return NULL from these functions if CONFIG_DEBUG_FS is not enabled
183 * so users have a chance to detect if there was a real error or not. We don't
184 * want to duplicate the design decision mistakes of procfs and devfs again.
187 static inline struct dentry *debugfs_lookup(const char *name,
188 struct dentry *parent)
190 return ERR_PTR(-ENODEV);
193 static inline struct dentry *debugfs_create_file(const char *name, umode_t mode,
194 struct dentry *parent, void *data,
195 const struct file_operations *fops)
197 return ERR_PTR(-ENODEV);
200 static inline struct dentry *debugfs_create_file_unsafe(const char *name,
201 umode_t mode, struct dentry *parent,
203 const struct file_operations *fops)
205 return ERR_PTR(-ENODEV);
208 static inline struct dentry *debugfs_create_file_size(const char *name, umode_t mode,
209 struct dentry *parent, void *data,
210 const struct file_operations *fops,
213 return ERR_PTR(-ENODEV);
216 static inline struct dentry *debugfs_create_dir(const char *name,
217 struct dentry *parent)
219 return ERR_PTR(-ENODEV);
222 static inline struct dentry *debugfs_create_symlink(const char *name,
223 struct dentry *parent,
226 return ERR_PTR(-ENODEV);
229 static inline struct dentry *debugfs_create_automount(const char *name,
230 struct dentry *parent,
231 debugfs_automount_t f,
234 return ERR_PTR(-ENODEV);
237 static inline void debugfs_remove(struct dentry *dentry)
240 static inline void debugfs_remove_recursive(struct dentry *dentry)
243 static inline int debugfs_use_file_start(const struct dentry *dentry,
245 __acquires(&debugfs_srcu)
250 static inline void debugfs_use_file_finish(int srcu_idx)
251 __releases(&debugfs_srcu)
254 static inline ssize_t debugfs_attr_read(struct file *file, char __user *buf,
255 size_t len, loff_t *ppos)
260 static inline ssize_t debugfs_attr_write(struct file *file,
261 const char __user *buf,
262 size_t len, loff_t *ppos)
267 static inline struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
268 struct dentry *new_dir, char *new_name)
270 return ERR_PTR(-ENODEV);
273 static inline struct dentry *debugfs_create_u8(const char *name, umode_t mode,
274 struct dentry *parent,
277 return ERR_PTR(-ENODEV);
280 static inline struct dentry *debugfs_create_u16(const char *name, umode_t mode,
281 struct dentry *parent,
284 return ERR_PTR(-ENODEV);
287 static inline struct dentry *debugfs_create_u32(const char *name, umode_t mode,
288 struct dentry *parent,
291 return ERR_PTR(-ENODEV);
294 static inline struct dentry *debugfs_create_u64(const char *name, umode_t mode,
295 struct dentry *parent,
298 return ERR_PTR(-ENODEV);
301 static inline struct dentry *debugfs_create_ulong(const char *name,
303 struct dentry *parent,
304 unsigned long *value)
306 return ERR_PTR(-ENODEV);
309 static inline struct dentry *debugfs_create_x8(const char *name, umode_t mode,
310 struct dentry *parent,
313 return ERR_PTR(-ENODEV);
316 static inline struct dentry *debugfs_create_x16(const char *name, umode_t mode,
317 struct dentry *parent,
320 return ERR_PTR(-ENODEV);
323 static inline struct dentry *debugfs_create_x32(const char *name, umode_t mode,
324 struct dentry *parent,
327 return ERR_PTR(-ENODEV);
330 static inline struct dentry *debugfs_create_x64(const char *name, umode_t mode,
331 struct dentry *parent,
334 return ERR_PTR(-ENODEV);
337 static inline struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
338 struct dentry *parent,
341 return ERR_PTR(-ENODEV);
344 static inline struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
345 struct dentry *parent, atomic_t *value)
347 return ERR_PTR(-ENODEV);
350 static inline struct dentry *debugfs_create_bool(const char *name, umode_t mode,
351 struct dentry *parent,
354 return ERR_PTR(-ENODEV);
357 static inline struct dentry *debugfs_create_blob(const char *name, umode_t mode,
358 struct dentry *parent,
359 struct debugfs_blob_wrapper *blob)
361 return ERR_PTR(-ENODEV);
364 static inline struct dentry *debugfs_create_regset32(const char *name,
365 umode_t mode, struct dentry *parent,
366 struct debugfs_regset32 *regset)
368 return ERR_PTR(-ENODEV);
371 static inline void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
372 int nregs, void __iomem *base, char *prefix)
376 static inline bool debugfs_initialized(void)
381 static inline struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
382 struct dentry *parent,
383 u32 *array, u32 elements)
385 return ERR_PTR(-ENODEV);
388 static inline struct dentry *debugfs_create_devm_seqfile(struct device *dev,
390 struct dentry *parent,
391 int (*read_fn)(struct seq_file *s,
394 return ERR_PTR(-ENODEV);
397 static inline ssize_t debugfs_read_file_bool(struct file *file,
398 char __user *user_buf,
399 size_t count, loff_t *ppos)
404 static inline ssize_t debugfs_write_file_bool(struct file *file,
405 const char __user *user_buf,
406 size_t count, loff_t *ppos)