xref: /linux-6.15/include/linux/debugfs.h (revision bf070bb0)
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 <[email protected]>
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 struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
137 					struct dentry *parent,
138 					u32 *array, u32 elements);
139 
140 struct dentry *debugfs_create_devm_seqfile(struct device *dev, const char *name,
141 					   struct dentry *parent,
142 					   int (*read_fn)(struct seq_file *s,
143 							  void *data));
144 
145 bool debugfs_initialized(void);
146 
147 ssize_t debugfs_read_file_bool(struct file *file, char __user *user_buf,
148 			       size_t count, loff_t *ppos);
149 
150 ssize_t debugfs_write_file_bool(struct file *file, const char __user *user_buf,
151 				size_t count, loff_t *ppos);
152 
153 #else
154 
155 #include <linux/err.h>
156 
157 /*
158  * We do not return NULL from these functions if CONFIG_DEBUG_FS is not enabled
159  * so users have a chance to detect if there was a real error or not.  We don't
160  * want to duplicate the design decision mistakes of procfs and devfs again.
161  */
162 
163 static inline struct dentry *debugfs_lookup(const char *name,
164 					    struct dentry *parent)
165 {
166 	return ERR_PTR(-ENODEV);
167 }
168 
169 static inline struct dentry *debugfs_create_file(const char *name, umode_t mode,
170 					struct dentry *parent, void *data,
171 					const struct file_operations *fops)
172 {
173 	return ERR_PTR(-ENODEV);
174 }
175 
176 static inline struct dentry *debugfs_create_file_unsafe(const char *name,
177 					umode_t mode, struct dentry *parent,
178 					void *data,
179 					const struct file_operations *fops)
180 {
181 	return ERR_PTR(-ENODEV);
182 }
183 
184 static inline struct dentry *debugfs_create_file_size(const char *name, umode_t mode,
185 					struct dentry *parent, void *data,
186 					const struct file_operations *fops,
187 					loff_t file_size)
188 {
189 	return ERR_PTR(-ENODEV);
190 }
191 
192 static inline struct dentry *debugfs_create_dir(const char *name,
193 						struct dentry *parent)
194 {
195 	return ERR_PTR(-ENODEV);
196 }
197 
198 static inline struct dentry *debugfs_create_symlink(const char *name,
199 						    struct dentry *parent,
200 						    const char *dest)
201 {
202 	return ERR_PTR(-ENODEV);
203 }
204 
205 static inline struct dentry *debugfs_create_automount(const char *name,
206 					struct dentry *parent,
207 					struct vfsmount *(*f)(void *),
208 					void *data)
209 {
210 	return ERR_PTR(-ENODEV);
211 }
212 
213 static inline void debugfs_remove(struct dentry *dentry)
214 { }
215 
216 static inline void debugfs_remove_recursive(struct dentry *dentry)
217 { }
218 
219 static inline int debugfs_file_get(struct dentry *dentry)
220 {
221 	return 0;
222 }
223 
224 static inline void debugfs_file_put(struct dentry *dentry)
225 { }
226 
227 static inline ssize_t debugfs_attr_read(struct file *file, char __user *buf,
228 					size_t len, loff_t *ppos)
229 {
230 	return -ENODEV;
231 }
232 
233 static inline ssize_t debugfs_attr_write(struct file *file,
234 					const char __user *buf,
235 					size_t len, loff_t *ppos)
236 {
237 	return -ENODEV;
238 }
239 
240 static inline struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
241                 struct dentry *new_dir, char *new_name)
242 {
243 	return ERR_PTR(-ENODEV);
244 }
245 
246 static inline struct dentry *debugfs_create_u8(const char *name, umode_t mode,
247 					       struct dentry *parent,
248 					       u8 *value)
249 {
250 	return ERR_PTR(-ENODEV);
251 }
252 
253 static inline struct dentry *debugfs_create_u16(const char *name, umode_t mode,
254 						struct dentry *parent,
255 						u16 *value)
256 {
257 	return ERR_PTR(-ENODEV);
258 }
259 
260 static inline struct dentry *debugfs_create_u32(const char *name, umode_t mode,
261 						struct dentry *parent,
262 						u32 *value)
263 {
264 	return ERR_PTR(-ENODEV);
265 }
266 
267 static inline struct dentry *debugfs_create_u64(const char *name, umode_t mode,
268 						struct dentry *parent,
269 						u64 *value)
270 {
271 	return ERR_PTR(-ENODEV);
272 }
273 
274 static inline struct dentry *debugfs_create_ulong(const char *name,
275 						umode_t mode,
276 						struct dentry *parent,
277 						unsigned long *value)
278 {
279 	return ERR_PTR(-ENODEV);
280 }
281 
282 static inline struct dentry *debugfs_create_x8(const char *name, umode_t mode,
283 					       struct dentry *parent,
284 					       u8 *value)
285 {
286 	return ERR_PTR(-ENODEV);
287 }
288 
289 static inline struct dentry *debugfs_create_x16(const char *name, umode_t mode,
290 						struct dentry *parent,
291 						u16 *value)
292 {
293 	return ERR_PTR(-ENODEV);
294 }
295 
296 static inline struct dentry *debugfs_create_x32(const char *name, umode_t mode,
297 						struct dentry *parent,
298 						u32 *value)
299 {
300 	return ERR_PTR(-ENODEV);
301 }
302 
303 static inline struct dentry *debugfs_create_x64(const char *name, umode_t mode,
304 						struct dentry *parent,
305 						u64 *value)
306 {
307 	return ERR_PTR(-ENODEV);
308 }
309 
310 static inline struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
311 				     struct dentry *parent,
312 				     size_t *value)
313 {
314 	return ERR_PTR(-ENODEV);
315 }
316 
317 static inline struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
318 				     struct dentry *parent, atomic_t *value)
319 {
320 	return ERR_PTR(-ENODEV);
321 }
322 
323 static inline struct dentry *debugfs_create_bool(const char *name, umode_t mode,
324 						 struct dentry *parent,
325 						 bool *value)
326 {
327 	return ERR_PTR(-ENODEV);
328 }
329 
330 static inline struct dentry *debugfs_create_blob(const char *name, umode_t mode,
331 				  struct dentry *parent,
332 				  struct debugfs_blob_wrapper *blob)
333 {
334 	return ERR_PTR(-ENODEV);
335 }
336 
337 static inline struct dentry *debugfs_create_regset32(const char *name,
338 				   umode_t mode, struct dentry *parent,
339 				   struct debugfs_regset32 *regset)
340 {
341 	return ERR_PTR(-ENODEV);
342 }
343 
344 static inline void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
345 			 int nregs, void __iomem *base, char *prefix)
346 {
347 }
348 
349 static inline bool debugfs_initialized(void)
350 {
351 	return false;
352 }
353 
354 static inline struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
355 					struct dentry *parent,
356 					u32 *array, u32 elements)
357 {
358 	return ERR_PTR(-ENODEV);
359 }
360 
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 
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 
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