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 void debugfs_create_u8(const char *name, umode_t mode, struct dentry *parent, 101 u8 *value); 102 void debugfs_create_u16(const char *name, umode_t mode, struct dentry *parent, 103 u16 *value); 104 struct dentry *debugfs_create_u32(const char *name, umode_t mode, 105 struct dentry *parent, u32 *value); 106 void debugfs_create_u64(const char *name, umode_t mode, struct dentry *parent, 107 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 void debugfs_create_x16(const char *name, umode_t mode, struct dentry *parent, 113 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 void 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 */ 161 162 static inline struct dentry *debugfs_lookup(const char *name, 163 struct dentry *parent) 164 { 165 return ERR_PTR(-ENODEV); 166 } 167 168 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 } 174 175 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 } 182 183 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 } 190 191 static inline struct dentry *debugfs_create_dir(const char *name, 192 struct dentry *parent) 193 { 194 return ERR_PTR(-ENODEV); 195 } 196 197 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 } 203 204 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 } 211 212 static inline void debugfs_remove(struct dentry *dentry) 213 { } 214 215 static inline void debugfs_remove_recursive(struct dentry *dentry) 216 { } 217 218 const struct file_operations *debugfs_real_fops(const struct file *filp); 219 220 static inline int debugfs_file_get(struct dentry *dentry) 221 { 222 return 0; 223 } 224 225 static inline void debugfs_file_put(struct dentry *dentry) 226 { } 227 228 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 } 233 234 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 } 240 241 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 } 246 247 static inline void debugfs_create_u8(const char *name, umode_t mode, 248 struct dentry *parent, u8 *value) { } 249 250 static inline void debugfs_create_u16(const char *name, umode_t mode, 251 struct dentry *parent, u16 *value) { } 252 253 static inline struct dentry *debugfs_create_u32(const char *name, umode_t mode, 254 struct dentry *parent, 255 u32 *value) 256 { 257 return ERR_PTR(-ENODEV); 258 } 259 260 static inline void debugfs_create_u64(const char *name, umode_t mode, 261 struct dentry *parent, u64 *value) { } 262 263 static inline struct dentry *debugfs_create_ulong(const char *name, 264 umode_t mode, 265 struct dentry *parent, 266 unsigned long *value) 267 { 268 return ERR_PTR(-ENODEV); 269 } 270 271 static inline struct dentry *debugfs_create_x8(const char *name, umode_t mode, 272 struct dentry *parent, 273 u8 *value) 274 { 275 return ERR_PTR(-ENODEV); 276 } 277 278 static inline void debugfs_create_x16(const char *name, umode_t mode, 279 struct dentry *parent, u16 *value) { } 280 281 static inline struct dentry *debugfs_create_x32(const char *name, umode_t mode, 282 struct dentry *parent, 283 u32 *value) 284 { 285 return ERR_PTR(-ENODEV); 286 } 287 288 static inline struct dentry *debugfs_create_x64(const char *name, umode_t mode, 289 struct dentry *parent, 290 u64 *value) 291 { 292 return ERR_PTR(-ENODEV); 293 } 294 295 static inline void debugfs_create_size_t(const char *name, umode_t mode, 296 struct dentry *parent, size_t *value) 297 { } 298 299 static inline struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode, 300 struct dentry *parent, atomic_t *value) 301 { 302 return ERR_PTR(-ENODEV); 303 } 304 305 static inline struct dentry *debugfs_create_bool(const char *name, umode_t mode, 306 struct dentry *parent, 307 bool *value) 308 { 309 return ERR_PTR(-ENODEV); 310 } 311 312 static inline struct dentry *debugfs_create_blob(const char *name, umode_t mode, 313 struct dentry *parent, 314 struct debugfs_blob_wrapper *blob) 315 { 316 return ERR_PTR(-ENODEV); 317 } 318 319 static inline struct dentry *debugfs_create_regset32(const char *name, 320 umode_t mode, struct dentry *parent, 321 struct debugfs_regset32 *regset) 322 { 323 return ERR_PTR(-ENODEV); 324 } 325 326 static inline void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs, 327 int nregs, void __iomem *base, char *prefix) 328 { 329 } 330 331 static inline bool debugfs_initialized(void) 332 { 333 return false; 334 } 335 336 static inline void debugfs_create_u32_array(const char *name, umode_t mode, 337 struct dentry *parent, u32 *array, 338 u32 elements) 339 { 340 } 341 342 static inline struct dentry *debugfs_create_devm_seqfile(struct device *dev, 343 const char *name, 344 struct dentry *parent, 345 int (*read_fn)(struct seq_file *s, 346 void *data)) 347 { 348 return ERR_PTR(-ENODEV); 349 } 350 351 static inline ssize_t debugfs_read_file_bool(struct file *file, 352 char __user *user_buf, 353 size_t count, loff_t *ppos) 354 { 355 return -ENODEV; 356 } 357 358 static inline ssize_t debugfs_write_file_bool(struct file *file, 359 const char __user *user_buf, 360 size_t count, loff_t *ppos) 361 { 362 return -ENODEV; 363 } 364 365 #endif 366 367 #endif 368