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 	struct device *dev;	/* Optional device for Runtime PM */
39 };
40 
41 extern struct dentry *arch_debugfs_dir;
42 
43 #define DEFINE_DEBUGFS_ATTRIBUTE_XSIGNED(__fops, __get, __set, __fmt, __is_signed)	\
44 static int __fops ## _open(struct inode *inode, struct file *file)	\
45 {									\
46 	__simple_attr_check_format(__fmt, 0ull);			\
47 	return simple_attr_open(inode, file, __get, __set, __fmt);	\
48 }									\
49 static const struct file_operations __fops = {				\
50 	.owner	 = THIS_MODULE,						\
51 	.open	 = __fops ## _open,					\
52 	.release = simple_attr_release,					\
53 	.read	 = debugfs_attr_read,					\
54 	.write	 = (__is_signed) ? debugfs_attr_write_signed : debugfs_attr_write,	\
55 	.llseek  = no_llseek,						\
56 }
57 
58 #define DEFINE_DEBUGFS_ATTRIBUTE(__fops, __get, __set, __fmt)		\
59 	DEFINE_DEBUGFS_ATTRIBUTE_XSIGNED(__fops, __get, __set, __fmt, false)
60 
61 #define DEFINE_DEBUGFS_ATTRIBUTE_SIGNED(__fops, __get, __set, __fmt)	\
62 	DEFINE_DEBUGFS_ATTRIBUTE_XSIGNED(__fops, __get, __set, __fmt, true)
63 
64 typedef struct vfsmount *(*debugfs_automount_t)(struct dentry *, void *);
65 
66 #if defined(CONFIG_DEBUG_FS)
67 
68 struct dentry *debugfs_lookup(const char *name, struct dentry *parent);
69 
70 struct dentry *debugfs_create_file(const char *name, umode_t mode,
71 				   struct dentry *parent, void *data,
72 				   const struct file_operations *fops);
73 struct dentry *debugfs_create_file_unsafe(const char *name, umode_t mode,
74 				   struct dentry *parent, void *data,
75 				   const struct file_operations *fops);
76 
77 struct dentry *debugfs_create_file_size(const char *name, umode_t mode,
78 					struct dentry *parent, void *data,
79 					const struct file_operations *fops,
80 					loff_t file_size);
81 
82 struct dentry *debugfs_create_dir(const char *name, struct dentry *parent);
83 
84 struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent,
85 				      const char *dest);
86 
87 struct dentry *debugfs_create_automount(const char *name,
88 					struct dentry *parent,
89 					debugfs_automount_t f,
90 					void *data);
91 
92 void debugfs_remove(struct dentry *dentry);
93 void debugfs_remove_recursive(struct dentry *dentry);
94 
95 void debugfs_lookup_and_remove(const char *name, struct dentry *parent);
96 
97 const struct file_operations *debugfs_real_fops(const struct file *filp);
98 
99 int debugfs_file_get(struct dentry *dentry);
100 void debugfs_file_put(struct dentry *dentry);
101 
102 ssize_t debugfs_attr_read(struct file *file, char __user *buf,
103 			size_t len, loff_t *ppos);
104 ssize_t debugfs_attr_write(struct file *file, const char __user *buf,
105 			size_t len, loff_t *ppos);
106 ssize_t debugfs_attr_write_signed(struct file *file, const char __user *buf,
107 			size_t len, loff_t *ppos);
108 
109 struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
110                 struct dentry *new_dir, const char *new_name);
111 
112 struct dentry *debugfs_create_u8(const char *name, umode_t mode,
113 				 struct dentry *parent, u8 *value);
114 struct dentry *debugfs_create_u16(const char *name, umode_t mode,
115 				  struct dentry *parent, u16 *value);
116 struct dentry *debugfs_create_u32(const char *name, umode_t mode,
117 				  struct dentry *parent, u32 *value);
118 struct dentry *debugfs_create_u64(const char *name, umode_t mode,
119 				  struct dentry *parent, u64 *value);
120 struct dentry *debugfs_create_ulong(const char *name, umode_t mode,
121 				    struct dentry *parent, unsigned long *value);
122 struct dentry *debugfs_create_x8(const char *name, umode_t mode,
123 				 struct dentry *parent, u8 *value);
124 struct dentry *debugfs_create_x16(const char *name, umode_t mode,
125 				  struct dentry *parent, u16 *value);
126 struct dentry *debugfs_create_x32(const char *name, umode_t mode,
127 				  struct dentry *parent, u32 *value);
128 struct dentry *debugfs_create_x64(const char *name, umode_t mode,
129 				  struct dentry *parent, u64 *value);
130 struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
131 				     struct dentry *parent, size_t *value);
132 struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
133 				     struct dentry *parent, atomic_t *value);
134 struct dentry *debugfs_create_bool(const char *name, umode_t mode,
135 				  struct dentry *parent, bool *value);
136 
137 struct dentry *debugfs_create_blob(const char *name, umode_t mode,
138 				  struct dentry *parent,
139 				  struct debugfs_blob_wrapper *blob);
140 
141 struct dentry *debugfs_create_regset32(const char *name, umode_t mode,
142 				     struct dentry *parent,
143 				     struct debugfs_regset32 *regset);
144 
145 void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
146 			  int nregs, void __iomem *base, char *prefix);
147 
148 struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
149 					struct dentry *parent,
150 					u32 *array, u32 elements);
151 
152 struct dentry *debugfs_create_devm_seqfile(struct device *dev, const char *name,
153 					   struct dentry *parent,
154 					   int (*read_fn)(struct seq_file *s,
155 							  void *data));
156 
157 bool debugfs_initialized(void);
158 
159 ssize_t debugfs_read_file_bool(struct file *file, char __user *user_buf,
160 			       size_t count, loff_t *ppos);
161 
162 ssize_t debugfs_write_file_bool(struct file *file, const char __user *user_buf,
163 				size_t count, loff_t *ppos);
164 
165 #else
166 
167 #include <linux/err.h>
168 
169 /*
170  * We do not return NULL from these functions if CONFIG_DEBUG_FS is not enabled
171  * so users have a chance to detect if there was a real error or not.  We don't
172  * want to duplicate the design decision mistakes of procfs and devfs again.
173  */
174 
debugfs_lookup(const char * name,struct dentry * parent)175 static inline struct dentry *debugfs_lookup(const char *name,
176 					    struct dentry *parent)
177 {
178 	return ERR_PTR(-ENODEV);
179 }
180 
debugfs_create_file(const char * name,umode_t mode,struct dentry * parent,void * data,const struct file_operations * fops)181 static inline struct dentry *debugfs_create_file(const char *name, umode_t mode,
182 					struct dentry *parent, void *data,
183 					const struct file_operations *fops)
184 {
185 	return ERR_PTR(-ENODEV);
186 }
187 
debugfs_create_file_unsafe(const char * name,umode_t mode,struct dentry * parent,void * data,const struct file_operations * fops)188 static inline struct dentry *debugfs_create_file_unsafe(const char *name,
189 					umode_t mode, struct dentry *parent,
190 					void *data,
191 					const struct file_operations *fops)
192 {
193 	return ERR_PTR(-ENODEV);
194 }
195 
debugfs_create_file_size(const char * name,umode_t mode,struct dentry * parent,void * data,const struct file_operations * fops,loff_t file_size)196 static inline struct dentry *debugfs_create_file_size(const char *name, umode_t mode,
197 					struct dentry *parent, void *data,
198 					const struct file_operations *fops,
199 					loff_t file_size)
200 {
201 	return ERR_PTR(-ENODEV);
202 }
203 
debugfs_create_dir(const char * name,struct dentry * parent)204 static inline struct dentry *debugfs_create_dir(const char *name,
205 						struct dentry *parent)
206 {
207 	return ERR_PTR(-ENODEV);
208 }
209 
debugfs_create_symlink(const char * name,struct dentry * parent,const char * dest)210 static inline struct dentry *debugfs_create_symlink(const char *name,
211 						    struct dentry *parent,
212 						    const char *dest)
213 {
214 	return ERR_PTR(-ENODEV);
215 }
216 
debugfs_create_automount(const char * name,struct dentry * parent,debugfs_automount_t f,void * data)217 static inline struct dentry *debugfs_create_automount(const char *name,
218 					struct dentry *parent,
219 					debugfs_automount_t f,
220 					void *data)
221 {
222 	return ERR_PTR(-ENODEV);
223 }
224 
debugfs_remove(struct dentry * dentry)225 static inline void debugfs_remove(struct dentry *dentry)
226 { }
227 
debugfs_remove_recursive(struct dentry * dentry)228 static inline void debugfs_remove_recursive(struct dentry *dentry)
229 { }
230 
debugfs_lookup_and_remove(const char * name,struct dentry * parent)231 static inline void debugfs_lookup_and_remove(const char *name,
232 					     struct dentry *parent)
233 { }
234 
235 const struct file_operations *debugfs_real_fops(const struct file *filp);
236 
debugfs_file_get(struct dentry * dentry)237 static inline int debugfs_file_get(struct dentry *dentry)
238 {
239 	return 0;
240 }
241 
debugfs_file_put(struct dentry * dentry)242 static inline void debugfs_file_put(struct dentry *dentry)
243 { }
244 
debugfs_attr_read(struct file * file,char __user * buf,size_t len,loff_t * ppos)245 static inline ssize_t debugfs_attr_read(struct file *file, char __user *buf,
246 					size_t len, loff_t *ppos)
247 {
248 	return -ENODEV;
249 }
250 
debugfs_attr_write(struct file * file,const char __user * buf,size_t len,loff_t * ppos)251 static inline ssize_t debugfs_attr_write(struct file *file,
252 					const char __user *buf,
253 					size_t len, loff_t *ppos)
254 {
255 	return -ENODEV;
256 }
257 
debugfs_attr_write_signed(struct file * file,const char __user * buf,size_t len,loff_t * ppos)258 static inline ssize_t debugfs_attr_write_signed(struct file *file,
259 					const char __user *buf,
260 					size_t len, loff_t *ppos)
261 {
262 	return -ENODEV;
263 }
264 
debugfs_rename(struct dentry * old_dir,struct dentry * old_dentry,struct dentry * new_dir,char * new_name)265 static inline struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
266                 struct dentry *new_dir, char *new_name)
267 {
268 	return ERR_PTR(-ENODEV);
269 }
270 
debugfs_create_u8(const char * name,umode_t mode,struct dentry * parent,u8 * value)271 static inline struct dentry *debugfs_create_u8(const char *name, umode_t mode,
272 					       struct dentry *parent,
273 					       u8 *value)
274 {
275 	return ERR_PTR(-ENODEV);
276 }
277 
debugfs_create_u16(const char * name,umode_t mode,struct dentry * parent,u16 * value)278 static inline struct dentry *debugfs_create_u16(const char *name, umode_t mode,
279 						struct dentry *parent,
280 						u16 *value)
281 {
282 	return ERR_PTR(-ENODEV);
283 }
284 
debugfs_create_u32(const char * name,umode_t mode,struct dentry * parent,u32 * value)285 static inline struct dentry *debugfs_create_u32(const char *name, umode_t mode,
286 						struct dentry *parent,
287 						u32 *value)
288 {
289 	return ERR_PTR(-ENODEV);
290 }
291 
debugfs_create_u64(const char * name,umode_t mode,struct dentry * parent,u64 * value)292 static inline struct dentry *debugfs_create_u64(const char *name, umode_t mode,
293 						struct dentry *parent,
294 						u64 *value)
295 {
296 	return ERR_PTR(-ENODEV);
297 }
298 
debugfs_create_ulong(const char * name,umode_t mode,struct dentry * parent,unsigned long * value)299 static inline struct dentry *debugfs_create_ulong(const char *name,
300 						umode_t mode,
301 						struct dentry *parent,
302 						unsigned long *value)
303 {
304 	return ERR_PTR(-ENODEV);
305 }
306 
debugfs_create_x8(const char * name,umode_t mode,struct dentry * parent,u8 * value)307 static inline struct dentry *debugfs_create_x8(const char *name, umode_t mode,
308 					       struct dentry *parent,
309 					       u8 *value)
310 {
311 	return ERR_PTR(-ENODEV);
312 }
313 
debugfs_create_x16(const char * name,umode_t mode,struct dentry * parent,u16 * value)314 static inline struct dentry *debugfs_create_x16(const char *name, umode_t mode,
315 						struct dentry *parent,
316 						u16 *value)
317 {
318 	return ERR_PTR(-ENODEV);
319 }
320 
debugfs_create_x32(const char * name,umode_t mode,struct dentry * parent,u32 * value)321 static inline struct dentry *debugfs_create_x32(const char *name, umode_t mode,
322 						struct dentry *parent,
323 						u32 *value)
324 {
325 	return ERR_PTR(-ENODEV);
326 }
327 
debugfs_create_x64(const char * name,umode_t mode,struct dentry * parent,u64 * value)328 static inline struct dentry *debugfs_create_x64(const char *name, umode_t mode,
329 						struct dentry *parent,
330 						u64 *value)
331 {
332 	return ERR_PTR(-ENODEV);
333 }
334 
debugfs_create_size_t(const char * name,umode_t mode,struct dentry * parent,size_t * value)335 static inline struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
336 				     struct dentry *parent,
337 				     size_t *value)
338 {
339 	return ERR_PTR(-ENODEV);
340 }
341 
debugfs_create_atomic_t(const char * name,umode_t mode,struct dentry * parent,atomic_t * value)342 static inline struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
343 				     struct dentry *parent, atomic_t *value)
344 {
345 	return ERR_PTR(-ENODEV);
346 }
347 
debugfs_create_bool(const char * name,umode_t mode,struct dentry * parent,bool * value)348 static inline struct dentry *debugfs_create_bool(const char *name, umode_t mode,
349 						 struct dentry *parent,
350 						 bool *value)
351 {
352 	return ERR_PTR(-ENODEV);
353 }
354 
debugfs_create_blob(const char * name,umode_t mode,struct dentry * parent,struct debugfs_blob_wrapper * blob)355 static inline struct dentry *debugfs_create_blob(const char *name, umode_t mode,
356 				  struct dentry *parent,
357 				  struct debugfs_blob_wrapper *blob)
358 {
359 	return ERR_PTR(-ENODEV);
360 }
361 
debugfs_create_regset32(const char * name,umode_t mode,struct dentry * parent,struct debugfs_regset32 * regset)362 static inline struct dentry *debugfs_create_regset32(const char *name,
363 				   umode_t mode, struct dentry *parent,
364 				   struct debugfs_regset32 *regset)
365 {
366 	return ERR_PTR(-ENODEV);
367 }
368 
debugfs_print_regs32(struct seq_file * s,const struct debugfs_reg32 * regs,int nregs,void __iomem * base,char * prefix)369 static inline void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
370 			 int nregs, void __iomem *base, char *prefix)
371 {
372 }
373 
debugfs_initialized(void)374 static inline bool debugfs_initialized(void)
375 {
376 	return false;
377 }
378 
debugfs_create_u32_array(const char * name,umode_t mode,struct dentry * parent,u32 * array,u32 elements)379 static inline struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
380 					struct dentry *parent,
381 					u32 *array, u32 elements)
382 {
383 	return ERR_PTR(-ENODEV);
384 }
385 
debugfs_create_devm_seqfile(struct device * dev,const char * name,struct dentry * parent,int (* read_fn)(struct seq_file * s,void * data))386 static inline struct dentry *debugfs_create_devm_seqfile(struct device *dev,
387 							 const char *name,
388 							 struct dentry *parent,
389 					   int (*read_fn)(struct seq_file *s,
390 							  void *data))
391 {
392 	return ERR_PTR(-ENODEV);
393 }
394 
debugfs_read_file_bool(struct file * file,char __user * user_buf,size_t count,loff_t * ppos)395 static inline ssize_t debugfs_read_file_bool(struct file *file,
396 					     char __user *user_buf,
397 					     size_t count, loff_t *ppos)
398 {
399 	return -ENODEV;
400 }
401 
debugfs_write_file_bool(struct file * file,const char __user * user_buf,size_t count,loff_t * ppos)402 static inline ssize_t debugfs_write_file_bool(struct file *file,
403 					      const char __user *user_buf,
404 					      size_t count, loff_t *ppos)
405 {
406 	return -ENODEV;
407 }
408 
409 #endif
410 
411 #endif
412