1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * debugfs.h - a tiny little debug file system
4 *
5 * Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
6 * Copyright (C) 2004 IBM Inc.
7 *
8 * debugfs is for people to use instead of /proc or /sys.
9 * See Documentation/filesystems/ for more details.
10 */
11
12 #ifndef _DEBUGFS_H_
13 #define _DEBUGFS_H_
14
15 #include <linux/fs.h>
16 #include <linux/seq_file.h>
17
18 #include <linux/types.h>
19 #include <linux/compiler.h>
20
21 struct device;
22 struct file_operations;
23
24 struct debugfs_blob_wrapper {
25 void *data;
26 unsigned long size;
27 };
28
29 struct debugfs_reg32 {
30 char *name;
31 unsigned long offset;
32 };
33
34 struct debugfs_regset32 {
35 const struct debugfs_reg32 *regs;
36 int nregs;
37 void __iomem *base;
38 };
39
40 extern struct dentry *arch_debugfs_dir;
41
42 #define DEFINE_DEBUGFS_ATTRIBUTE(__fops, __get, __set, __fmt) \
43 static int __fops ## _open(struct inode *inode, struct file *file) \
44 { \
45 __simple_attr_check_format(__fmt, 0ull); \
46 return simple_attr_open(inode, file, __get, __set, __fmt); \
47 } \
48 static const struct file_operations __fops = { \
49 .owner = THIS_MODULE, \
50 .open = __fops ## _open, \
51 .release = simple_attr_release, \
52 .read = debugfs_attr_read, \
53 .write = debugfs_attr_write, \
54 .llseek = no_llseek, \
55 }
56
57 #if defined(CONFIG_DEBUG_FS)
58
59 struct dentry *debugfs_lookup(const char *name, struct dentry *parent);
60
61 struct dentry *debugfs_create_file(const char *name, umode_t mode,
62 struct dentry *parent, void *data,
63 const struct file_operations *fops);
64 struct dentry *debugfs_create_file_unsafe(const char *name, umode_t mode,
65 struct dentry *parent, void *data,
66 const struct file_operations *fops);
67
68 struct dentry *debugfs_create_file_size(const char *name, umode_t mode,
69 struct dentry *parent, void *data,
70 const struct file_operations *fops,
71 loff_t file_size);
72
73 struct dentry *debugfs_create_dir(const char *name, struct dentry *parent);
74
75 struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent,
76 const char *dest);
77
78 typedef struct vfsmount *(*debugfs_automount_t)(struct dentry *, void *);
79 struct dentry *debugfs_create_automount(const char *name,
80 struct dentry *parent,
81 debugfs_automount_t f,
82 void *data);
83
84 void debugfs_remove(struct dentry *dentry);
85 void debugfs_remove_recursive(struct dentry *dentry);
86
87 const struct file_operations *debugfs_real_fops(const struct file *filp);
88
89 int debugfs_file_get(struct dentry *dentry);
90 void debugfs_file_put(struct dentry *dentry);
91
92 ssize_t debugfs_attr_read(struct file *file, char __user *buf,
93 size_t len, loff_t *ppos);
94 ssize_t debugfs_attr_write(struct file *file, const char __user *buf,
95 size_t len, loff_t *ppos);
96
97 struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
98 struct dentry *new_dir, const char *new_name);
99
100 struct dentry *debugfs_create_u8(const char *name, umode_t mode,
101 struct dentry *parent, u8 *value);
102 struct dentry *debugfs_create_u16(const char *name, umode_t mode,
103 struct dentry *parent, u16 *value);
104 struct dentry *debugfs_create_u32(const char *name, umode_t mode,
105 struct dentry *parent, u32 *value);
106 struct dentry *debugfs_create_u64(const char *name, umode_t mode,
107 struct dentry *parent, u64 *value);
108 struct dentry *debugfs_create_ulong(const char *name, umode_t mode,
109 struct dentry *parent, unsigned long *value);
110 struct dentry *debugfs_create_x8(const char *name, umode_t mode,
111 struct dentry *parent, u8 *value);
112 struct dentry *debugfs_create_x16(const char *name, umode_t mode,
113 struct dentry *parent, u16 *value);
114 struct dentry *debugfs_create_x32(const char *name, umode_t mode,
115 struct dentry *parent, u32 *value);
116 struct dentry *debugfs_create_x64(const char *name, umode_t mode,
117 struct dentry *parent, u64 *value);
118 struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
119 struct dentry *parent, size_t *value);
120 struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
121 struct dentry *parent, atomic_t *value);
122 struct dentry *debugfs_create_bool(const char *name, umode_t mode,
123 struct dentry *parent, bool *value);
124
125 struct dentry *debugfs_create_blob(const char *name, umode_t mode,
126 struct dentry *parent,
127 struct debugfs_blob_wrapper *blob);
128
129 struct dentry *debugfs_create_regset32(const char *name, umode_t mode,
130 struct dentry *parent,
131 struct debugfs_regset32 *regset);
132
133 void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
134 int nregs, void __iomem *base, char *prefix);
135
136 void debugfs_create_u32_array(const char *name, umode_t mode,
137 struct dentry *parent, u32 *array, u32 elements);
138
139 struct dentry *debugfs_create_devm_seqfile(struct device *dev, const char *name,
140 struct dentry *parent,
141 int (*read_fn)(struct seq_file *s,
142 void *data));
143
144 bool debugfs_initialized(void);
145
146 ssize_t debugfs_read_file_bool(struct file *file, char __user *user_buf,
147 size_t count, loff_t *ppos);
148
149 ssize_t debugfs_write_file_bool(struct file *file, const char __user *user_buf,
150 size_t count, loff_t *ppos);
151
152 #else
153
154 #include <linux/err.h>
155
156 /*
157 * We do not return NULL from these functions if CONFIG_DEBUG_FS is not enabled
158 * so users have a chance to detect if there was a real error or not. We don't
159 * want to duplicate the design decision mistakes of procfs and devfs again.
160 */
161
debugfs_lookup(const char * name,struct dentry * parent)162 static inline struct dentry *debugfs_lookup(const char *name,
163 struct dentry *parent)
164 {
165 return ERR_PTR(-ENODEV);
166 }
167
debugfs_create_file(const char * name,umode_t mode,struct dentry * parent,void * data,const struct file_operations * fops)168 static inline struct dentry *debugfs_create_file(const char *name, umode_t mode,
169 struct dentry *parent, void *data,
170 const struct file_operations *fops)
171 {
172 return ERR_PTR(-ENODEV);
173 }
174
debugfs_create_file_unsafe(const char * name,umode_t mode,struct dentry * parent,void * data,const struct file_operations * fops)175 static inline struct dentry *debugfs_create_file_unsafe(const char *name,
176 umode_t mode, struct dentry *parent,
177 void *data,
178 const struct file_operations *fops)
179 {
180 return ERR_PTR(-ENODEV);
181 }
182
debugfs_create_file_size(const char * name,umode_t mode,struct dentry * parent,void * data,const struct file_operations * fops,loff_t file_size)183 static inline struct dentry *debugfs_create_file_size(const char *name, umode_t mode,
184 struct dentry *parent, void *data,
185 const struct file_operations *fops,
186 loff_t file_size)
187 {
188 return ERR_PTR(-ENODEV);
189 }
190
debugfs_create_dir(const char * name,struct dentry * parent)191 static inline struct dentry *debugfs_create_dir(const char *name,
192 struct dentry *parent)
193 {
194 return ERR_PTR(-ENODEV);
195 }
196
debugfs_create_symlink(const char * name,struct dentry * parent,const char * dest)197 static inline struct dentry *debugfs_create_symlink(const char *name,
198 struct dentry *parent,
199 const char *dest)
200 {
201 return ERR_PTR(-ENODEV);
202 }
203
debugfs_create_automount(const char * name,struct dentry * parent,struct vfsmount * (* f)(void *),void * data)204 static inline struct dentry *debugfs_create_automount(const char *name,
205 struct dentry *parent,
206 struct vfsmount *(*f)(void *),
207 void *data)
208 {
209 return ERR_PTR(-ENODEV);
210 }
211
debugfs_remove(struct dentry * dentry)212 static inline void debugfs_remove(struct dentry *dentry)
213 { }
214
debugfs_remove_recursive(struct dentry * dentry)215 static inline void debugfs_remove_recursive(struct dentry *dentry)
216 { }
217
218 const struct file_operations *debugfs_real_fops(const struct file *filp);
219
debugfs_file_get(struct dentry * dentry)220 static inline int debugfs_file_get(struct dentry *dentry)
221 {
222 return 0;
223 }
224
debugfs_file_put(struct dentry * dentry)225 static inline void debugfs_file_put(struct dentry *dentry)
226 { }
227
debugfs_attr_read(struct file * file,char __user * buf,size_t len,loff_t * ppos)228 static inline ssize_t debugfs_attr_read(struct file *file, char __user *buf,
229 size_t len, loff_t *ppos)
230 {
231 return -ENODEV;
232 }
233
debugfs_attr_write(struct file * file,const char __user * buf,size_t len,loff_t * ppos)234 static inline ssize_t debugfs_attr_write(struct file *file,
235 const char __user *buf,
236 size_t len, loff_t *ppos)
237 {
238 return -ENODEV;
239 }
240
debugfs_rename(struct dentry * old_dir,struct dentry * old_dentry,struct dentry * new_dir,char * new_name)241 static inline struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
242 struct dentry *new_dir, char *new_name)
243 {
244 return ERR_PTR(-ENODEV);
245 }
246
debugfs_create_u8(const char * name,umode_t mode,struct dentry * parent,u8 * value)247 static inline struct dentry *debugfs_create_u8(const char *name, umode_t mode,
248 struct dentry *parent,
249 u8 *value)
250 {
251 return ERR_PTR(-ENODEV);
252 }
253
debugfs_create_u16(const char * name,umode_t mode,struct dentry * parent,u16 * value)254 static inline struct dentry *debugfs_create_u16(const char *name, umode_t mode,
255 struct dentry *parent,
256 u16 *value)
257 {
258 return ERR_PTR(-ENODEV);
259 }
260
debugfs_create_u32(const char * name,umode_t mode,struct dentry * parent,u32 * value)261 static inline struct dentry *debugfs_create_u32(const char *name, umode_t mode,
262 struct dentry *parent,
263 u32 *value)
264 {
265 return ERR_PTR(-ENODEV);
266 }
267
debugfs_create_u64(const char * name,umode_t mode,struct dentry * parent,u64 * value)268 static inline struct dentry *debugfs_create_u64(const char *name, umode_t mode,
269 struct dentry *parent,
270 u64 *value)
271 {
272 return ERR_PTR(-ENODEV);
273 }
274
debugfs_create_ulong(const char * name,umode_t mode,struct dentry * parent,unsigned long * value)275 static inline struct dentry *debugfs_create_ulong(const char *name,
276 umode_t mode,
277 struct dentry *parent,
278 unsigned long *value)
279 {
280 return ERR_PTR(-ENODEV);
281 }
282
debugfs_create_x8(const char * name,umode_t mode,struct dentry * parent,u8 * value)283 static inline struct dentry *debugfs_create_x8(const char *name, umode_t mode,
284 struct dentry *parent,
285 u8 *value)
286 {
287 return ERR_PTR(-ENODEV);
288 }
289
debugfs_create_x16(const char * name,umode_t mode,struct dentry * parent,u16 * value)290 static inline struct dentry *debugfs_create_x16(const char *name, umode_t mode,
291 struct dentry *parent,
292 u16 *value)
293 {
294 return ERR_PTR(-ENODEV);
295 }
296
debugfs_create_x32(const char * name,umode_t mode,struct dentry * parent,u32 * value)297 static inline struct dentry *debugfs_create_x32(const char *name, umode_t mode,
298 struct dentry *parent,
299 u32 *value)
300 {
301 return ERR_PTR(-ENODEV);
302 }
303
debugfs_create_x64(const char * name,umode_t mode,struct dentry * parent,u64 * value)304 static inline struct dentry *debugfs_create_x64(const char *name, umode_t mode,
305 struct dentry *parent,
306 u64 *value)
307 {
308 return ERR_PTR(-ENODEV);
309 }
310
debugfs_create_size_t(const char * name,umode_t mode,struct dentry * parent,size_t * value)311 static inline struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
312 struct dentry *parent,
313 size_t *value)
314 {
315 return ERR_PTR(-ENODEV);
316 }
317
debugfs_create_atomic_t(const char * name,umode_t mode,struct dentry * parent,atomic_t * value)318 static inline struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
319 struct dentry *parent, atomic_t *value)
320 {
321 return ERR_PTR(-ENODEV);
322 }
323
debugfs_create_bool(const char * name,umode_t mode,struct dentry * parent,bool * value)324 static inline struct dentry *debugfs_create_bool(const char *name, umode_t mode,
325 struct dentry *parent,
326 bool *value)
327 {
328 return ERR_PTR(-ENODEV);
329 }
330
debugfs_create_blob(const char * name,umode_t mode,struct dentry * parent,struct debugfs_blob_wrapper * blob)331 static inline struct dentry *debugfs_create_blob(const char *name, umode_t mode,
332 struct dentry *parent,
333 struct debugfs_blob_wrapper *blob)
334 {
335 return ERR_PTR(-ENODEV);
336 }
337
debugfs_create_regset32(const char * name,umode_t mode,struct dentry * parent,struct debugfs_regset32 * regset)338 static inline struct dentry *debugfs_create_regset32(const char *name,
339 umode_t mode, struct dentry *parent,
340 struct debugfs_regset32 *regset)
341 {
342 return ERR_PTR(-ENODEV);
343 }
344
debugfs_print_regs32(struct seq_file * s,const struct debugfs_reg32 * regs,int nregs,void __iomem * base,char * prefix)345 static inline void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
346 int nregs, void __iomem *base, char *prefix)
347 {
348 }
349
debugfs_initialized(void)350 static inline bool debugfs_initialized(void)
351 {
352 return false;
353 }
354
debugfs_create_u32_array(const char * name,umode_t mode,struct dentry * parent,u32 * array,u32 elements)355 static inline void debugfs_create_u32_array(const char *name, umode_t mode,
356 struct dentry *parent, u32 *array,
357 u32 elements)
358 {
359 }
360
debugfs_create_devm_seqfile(struct device * dev,const char * name,struct dentry * parent,int (* read_fn)(struct seq_file * s,void * data))361 static inline struct dentry *debugfs_create_devm_seqfile(struct device *dev,
362 const char *name,
363 struct dentry *parent,
364 int (*read_fn)(struct seq_file *s,
365 void *data))
366 {
367 return ERR_PTR(-ENODEV);
368 }
369
debugfs_read_file_bool(struct file * file,char __user * user_buf,size_t count,loff_t * ppos)370 static inline ssize_t debugfs_read_file_bool(struct file *file,
371 char __user *user_buf,
372 size_t count, loff_t *ppos)
373 {
374 return -ENODEV;
375 }
376
debugfs_write_file_bool(struct file * file,const char __user * user_buf,size_t count,loff_t * ppos)377 static inline ssize_t debugfs_write_file_bool(struct file *file,
378 const char __user *user_buf,
379 size_t count, loff_t *ppos)
380 {
381 return -ENODEV;
382 }
383
384 #endif
385
386 #endif
387
