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 struct debugfs_u32_array {
42 u32 *array;
43 u32 n_elements;
44 };
45
46 extern struct dentry *arch_debugfs_dir;
47
48 #define DEFINE_DEBUGFS_ATTRIBUTE_XSIGNED(__fops, __get, __set, __fmt, __is_signed) \
49 static int __fops ## _open(struct inode *inode, struct file *file) \
50 { \
51 __simple_attr_check_format(__fmt, 0ull); \
52 return simple_attr_open(inode, file, __get, __set, __fmt); \
53 } \
54 static const struct file_operations __fops = { \
55 .owner = THIS_MODULE, \
56 .open = __fops ## _open, \
57 .release = simple_attr_release, \
58 .read = debugfs_attr_read, \
59 .write = (__is_signed) ? debugfs_attr_write_signed : debugfs_attr_write, \
60 .llseek = no_llseek, \
61 }
62
63 #define DEFINE_DEBUGFS_ATTRIBUTE(__fops, __get, __set, __fmt) \
64 DEFINE_DEBUGFS_ATTRIBUTE_XSIGNED(__fops, __get, __set, __fmt, false)
65
66 #define DEFINE_DEBUGFS_ATTRIBUTE_SIGNED(__fops, __get, __set, __fmt) \
67 DEFINE_DEBUGFS_ATTRIBUTE_XSIGNED(__fops, __get, __set, __fmt, true)
68
69 typedef struct vfsmount *(*debugfs_automount_t)(struct dentry *, void *);
70
71 #if defined(CONFIG_DEBUG_FS)
72
73 struct dentry *debugfs_lookup(const char *name, struct dentry *parent);
74
75 struct dentry *debugfs_create_file(const char *name, umode_t mode,
76 struct dentry *parent, void *data,
77 const struct file_operations *fops);
78 struct dentry *debugfs_create_file_unsafe(const char *name, umode_t mode,
79 struct dentry *parent, void *data,
80 const struct file_operations *fops);
81
82 void debugfs_create_file_size(const char *name, umode_t mode,
83 struct dentry *parent, void *data,
84 const struct file_operations *fops,
85 loff_t file_size);
86
87 struct dentry *debugfs_create_dir(const char *name, struct dentry *parent);
88
89 struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent,
90 const char *dest);
91
92 struct dentry *debugfs_create_automount(const char *name,
93 struct dentry *parent,
94 debugfs_automount_t f,
95 void *data);
96
97 void debugfs_remove(struct dentry *dentry);
98 #define debugfs_remove_recursive debugfs_remove
99
100 void debugfs_lookup_and_remove(const char *name, struct dentry *parent);
101
102 const struct file_operations *debugfs_real_fops(const struct file *filp);
103
104 int debugfs_file_get(struct dentry *dentry);
105 void debugfs_file_put(struct dentry *dentry);
106
107 ssize_t debugfs_attr_read(struct file *file, char __user *buf,
108 size_t len, loff_t *ppos);
109 ssize_t debugfs_attr_write(struct file *file, const char __user *buf,
110 size_t len, loff_t *ppos);
111 ssize_t debugfs_attr_write_signed(struct file *file, const char __user *buf,
112 size_t len, loff_t *ppos);
113
114 struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
115 struct dentry *new_dir, const char *new_name);
116
117 void debugfs_create_u8(const char *name, umode_t mode, struct dentry *parent,
118 u8 *value);
119 void debugfs_create_u16(const char *name, umode_t mode, struct dentry *parent,
120 u16 *value);
121 void debugfs_create_u32(const char *name, umode_t mode, struct dentry *parent,
122 u32 *value);
123 void debugfs_create_u64(const char *name, umode_t mode, struct dentry *parent,
124 u64 *value);
125 struct dentry *debugfs_create_ulong(const char *name, umode_t mode,
126 struct dentry *parent, unsigned long *value);
127 void debugfs_create_x8(const char *name, umode_t mode, struct dentry *parent,
128 u8 *value);
129 void debugfs_create_x16(const char *name, umode_t mode, struct dentry *parent,
130 u16 *value);
131 void debugfs_create_x32(const char *name, umode_t mode, struct dentry *parent,
132 u32 *value);
133 void debugfs_create_x64(const char *name, umode_t mode, struct dentry *parent,
134 u64 *value);
135 void debugfs_create_size_t(const char *name, umode_t mode,
136 struct dentry *parent, size_t *value);
137 void debugfs_create_atomic_t(const char *name, umode_t mode,
138 struct dentry *parent, atomic_t *value);
139 struct dentry *debugfs_create_bool(const char *name, umode_t mode,
140 struct dentry *parent, bool *value);
141
142 struct dentry *debugfs_create_blob(const char *name, umode_t mode,
143 struct dentry *parent,
144 struct debugfs_blob_wrapper *blob);
145
146 void debugfs_create_regset32(const char *name, umode_t mode,
147 struct dentry *parent,
148 struct debugfs_regset32 *regset);
149
150 void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
151 int nregs, void __iomem *base, char *prefix);
152
153 void debugfs_create_u32_array(const char *name, umode_t mode,
154 struct dentry *parent,
155 struct debugfs_u32_array *array);
156
157 void debugfs_create_devm_seqfile(struct device *dev, const char *name,
158 struct dentry *parent,
159 int (*read_fn)(struct seq_file *s, void *data));
160
161 bool debugfs_initialized(void);
162
163 ssize_t debugfs_read_file_bool(struct file *file, char __user *user_buf,
164 size_t count, loff_t *ppos);
165
166 ssize_t debugfs_write_file_bool(struct file *file, const char __user *user_buf,
167 size_t count, loff_t *ppos);
168
169 #else
170
171 #include <linux/err.h>
172
173 /*
174 * We do not return NULL from these functions if CONFIG_DEBUG_FS is not enabled
175 * so users have a chance to detect if there was a real error or not. We don't
176 * want to duplicate the design decision mistakes of procfs and devfs again.
177 */
178
debugfs_lookup(const char * name,struct dentry * parent)179 static inline struct dentry *debugfs_lookup(const char *name,
180 struct dentry *parent)
181 {
182 return ERR_PTR(-ENODEV);
183 }
184
debugfs_create_file(const char * name,umode_t mode,struct dentry * parent,void * data,const struct file_operations * fops)185 static inline struct dentry *debugfs_create_file(const char *name, umode_t mode,
186 struct dentry *parent, void *data,
187 const struct file_operations *fops)
188 {
189 return ERR_PTR(-ENODEV);
190 }
191
debugfs_create_file_unsafe(const char * name,umode_t mode,struct dentry * parent,void * data,const struct file_operations * fops)192 static inline struct dentry *debugfs_create_file_unsafe(const char *name,
193 umode_t mode, struct dentry *parent,
194 void *data,
195 const struct file_operations *fops)
196 {
197 return ERR_PTR(-ENODEV);
198 }
199
debugfs_create_file_size(const char * name,umode_t mode,struct dentry * parent,void * data,const struct file_operations * fops,loff_t file_size)200 static inline void debugfs_create_file_size(const char *name, umode_t mode,
201 struct dentry *parent, void *data,
202 const struct file_operations *fops,
203 loff_t file_size)
204 { }
205
debugfs_create_dir(const char * name,struct dentry * parent)206 static inline struct dentry *debugfs_create_dir(const char *name,
207 struct dentry *parent)
208 {
209 return ERR_PTR(-ENODEV);
210 }
211
debugfs_create_symlink(const char * name,struct dentry * parent,const char * dest)212 static inline struct dentry *debugfs_create_symlink(const char *name,
213 struct dentry *parent,
214 const char *dest)
215 {
216 return ERR_PTR(-ENODEV);
217 }
218
debugfs_create_automount(const char * name,struct dentry * parent,debugfs_automount_t f,void * data)219 static inline struct dentry *debugfs_create_automount(const char *name,
220 struct dentry *parent,
221 debugfs_automount_t f,
222 void *data)
223 {
224 return ERR_PTR(-ENODEV);
225 }
226
debugfs_remove(struct dentry * dentry)227 static inline void debugfs_remove(struct dentry *dentry)
228 { }
229
debugfs_remove_recursive(struct dentry * dentry)230 static inline void debugfs_remove_recursive(struct dentry *dentry)
231 { }
232
debugfs_lookup_and_remove(const char * name,struct dentry * parent)233 static inline void debugfs_lookup_and_remove(const char *name,
234 struct dentry *parent)
235 { }
236
237 const struct file_operations *debugfs_real_fops(const struct file *filp);
238
debugfs_file_get(struct dentry * dentry)239 static inline int debugfs_file_get(struct dentry *dentry)
240 {
241 return 0;
242 }
243
debugfs_file_put(struct dentry * dentry)244 static inline void debugfs_file_put(struct dentry *dentry)
245 { }
246
debugfs_attr_read(struct file * file,char __user * buf,size_t len,loff_t * ppos)247 static inline ssize_t debugfs_attr_read(struct file *file, char __user *buf,
248 size_t len, loff_t *ppos)
249 {
250 return -ENODEV;
251 }
252
debugfs_attr_write(struct file * file,const char __user * buf,size_t len,loff_t * ppos)253 static inline ssize_t debugfs_attr_write(struct file *file,
254 const char __user *buf,
255 size_t len, loff_t *ppos)
256 {
257 return -ENODEV;
258 }
259
debugfs_attr_write_signed(struct file * file,const char __user * buf,size_t len,loff_t * ppos)260 static inline ssize_t debugfs_attr_write_signed(struct file *file,
261 const char __user *buf,
262 size_t len, loff_t *ppos)
263 {
264 return -ENODEV;
265 }
266
debugfs_rename(struct dentry * old_dir,struct dentry * old_dentry,struct dentry * new_dir,char * new_name)267 static inline struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
268 struct dentry *new_dir, char *new_name)
269 {
270 return ERR_PTR(-ENODEV);
271 }
272
debugfs_create_u8(const char * name,umode_t mode,struct dentry * parent,u8 * value)273 static inline void debugfs_create_u8(const char *name, umode_t mode,
274 struct dentry *parent, u8 *value) { }
275
debugfs_create_u16(const char * name,umode_t mode,struct dentry * parent,u16 * value)276 static inline void debugfs_create_u16(const char *name, umode_t mode,
277 struct dentry *parent, u16 *value) { }
278
debugfs_create_u32(const char * name,umode_t mode,struct dentry * parent,u32 * value)279 static inline void debugfs_create_u32(const char *name, umode_t mode,
280 struct dentry *parent, u32 *value) { }
281
debugfs_create_u64(const char * name,umode_t mode,struct dentry * parent,u64 * value)282 static inline void debugfs_create_u64(const char *name, umode_t mode,
283 struct dentry *parent, u64 *value) { }
284
debugfs_create_ulong(const char * name,umode_t mode,struct dentry * parent,unsigned long * value)285 static inline struct dentry *debugfs_create_ulong(const char *name,
286 umode_t mode,
287 struct dentry *parent,
288 unsigned long *value)
289 {
290 return ERR_PTR(-ENODEV);
291 }
292
debugfs_create_x8(const char * name,umode_t mode,struct dentry * parent,u8 * value)293 static inline void debugfs_create_x8(const char *name, umode_t mode,
294 struct dentry *parent, u8 *value) { }
295
debugfs_create_x16(const char * name,umode_t mode,struct dentry * parent,u16 * value)296 static inline void debugfs_create_x16(const char *name, umode_t mode,
297 struct dentry *parent, u16 *value) { }
298
debugfs_create_x32(const char * name,umode_t mode,struct dentry * parent,u32 * value)299 static inline void debugfs_create_x32(const char *name, umode_t mode,
300 struct dentry *parent, u32 *value) { }
301
debugfs_create_x64(const char * name,umode_t mode,struct dentry * parent,u64 * value)302 static inline void debugfs_create_x64(const char *name, umode_t mode,
303 struct dentry *parent, u64 *value) { }
304
debugfs_create_size_t(const char * name,umode_t mode,struct dentry * parent,size_t * value)305 static inline void debugfs_create_size_t(const char *name, umode_t mode,
306 struct dentry *parent, size_t *value)
307 { }
308
debugfs_create_atomic_t(const char * name,umode_t mode,struct dentry * parent,atomic_t * value)309 static inline void debugfs_create_atomic_t(const char *name, umode_t mode,
310 struct dentry *parent,
311 atomic_t *value)
312 { }
313
debugfs_create_bool(const char * name,umode_t mode,struct dentry * parent,bool * value)314 static inline struct dentry *debugfs_create_bool(const char *name, umode_t mode,
315 struct dentry *parent,
316 bool *value)
317 {
318 return ERR_PTR(-ENODEV);
319 }
320
debugfs_create_blob(const char * name,umode_t mode,struct dentry * parent,struct debugfs_blob_wrapper * blob)321 static inline struct dentry *debugfs_create_blob(const char *name, umode_t mode,
322 struct dentry *parent,
323 struct debugfs_blob_wrapper *blob)
324 {
325 return ERR_PTR(-ENODEV);
326 }
327
debugfs_create_regset32(const char * name,umode_t mode,struct dentry * parent,struct debugfs_regset32 * regset)328 static inline void debugfs_create_regset32(const char *name, umode_t mode,
329 struct dentry *parent,
330 struct debugfs_regset32 *regset)
331 {
332 }
333
debugfs_print_regs32(struct seq_file * s,const struct debugfs_reg32 * regs,int nregs,void __iomem * base,char * prefix)334 static inline void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
335 int nregs, void __iomem *base, char *prefix)
336 {
337 }
338
debugfs_initialized(void)339 static inline bool debugfs_initialized(void)
340 {
341 return false;
342 }
343
debugfs_create_u32_array(const char * name,umode_t mode,struct dentry * parent,struct debugfs_u32_array * array)344 static inline void debugfs_create_u32_array(const char *name, umode_t mode,
345 struct dentry *parent,
346 struct debugfs_u32_array *array)
347 {
348 }
349
debugfs_create_devm_seqfile(struct device * dev,const char * name,struct dentry * parent,int (* read_fn)(struct seq_file * s,void * data))350 static inline void debugfs_create_devm_seqfile(struct device *dev,
351 const char *name,
352 struct dentry *parent,
353 int (*read_fn)(struct seq_file *s,
354 void *data))
355 {
356 }
357
debugfs_read_file_bool(struct file * file,char __user * user_buf,size_t count,loff_t * ppos)358 static inline ssize_t debugfs_read_file_bool(struct file *file,
359 char __user *user_buf,
360 size_t count, loff_t *ppos)
361 {
362 return -ENODEV;
363 }
364
debugfs_write_file_bool(struct file * file,const char __user * user_buf,size_t count,loff_t * ppos)365 static inline ssize_t debugfs_write_file_bool(struct file *file,
366 const char __user *user_buf,
367 size_t count, loff_t *ppos)
368 {
369 return -ENODEV;
370 }
371
372 #endif
373
374 /**
375 * debugfs_create_xul - create a debugfs file that is used to read and write an
376 * unsigned long value, formatted in hexadecimal
377 * @name: a pointer to a string containing the name of the file to create.
378 * @mode: the permission that the file should have
379 * @parent: a pointer to the parent dentry for this file. This should be a
380 * directory dentry if set. If this parameter is %NULL, then the
381 * file will be created in the root of the debugfs filesystem.
382 * @value: a pointer to the variable that the file should read to and write
383 * from.
384 */
debugfs_create_xul(const char * name,umode_t mode,struct dentry * parent,unsigned long * value)385 static inline void debugfs_create_xul(const char *name, umode_t mode,
386 struct dentry *parent,
387 unsigned long *value)
388 {
389 if (sizeof(*value) == sizeof(u32))
390 debugfs_create_x32(name, mode, parent, (u32 *)value);
391 else
392 debugfs_create_x64(name, mode, parent, (u64 *)value);
393 }
394
395 #endif
396