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