1 /* 2 * debugfs.h - a tiny little debug file system 3 * 4 * Copyright (C) 2004 Greg Kroah-Hartman <[email protected]> 5 * Copyright (C) 2004 IBM Inc. 6 * 7 * This program is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License version 9 * 2 as published by the Free Software Foundation. 10 * 11 * debugfs is for people to use instead of /proc or /sys. 12 * See Documentation/DocBook/filesystems for more details. 13 */ 14 15 #ifndef _DEBUGFS_H_ 16 #define _DEBUGFS_H_ 17 18 #include <linux/fs.h> 19 #include <linux/seq_file.h> 20 21 #include <linux/types.h> 22 #include <linux/compiler.h> 23 24 struct device; 25 struct file_operations; 26 struct srcu_struct; 27 28 struct debugfs_blob_wrapper { 29 void *data; 30 unsigned long size; 31 }; 32 33 struct debugfs_reg32 { 34 char *name; 35 unsigned long offset; 36 }; 37 38 struct debugfs_regset32 { 39 const struct debugfs_reg32 *regs; 40 int nregs; 41 void __iomem *base; 42 }; 43 44 extern struct dentry *arch_debugfs_dir; 45 46 extern struct srcu_struct debugfs_srcu; 47 48 #if defined(CONFIG_DEBUG_FS) 49 50 struct dentry *debugfs_create_file(const char *name, umode_t mode, 51 struct dentry *parent, void *data, 52 const struct file_operations *fops); 53 struct dentry *debugfs_create_file_unsafe(const char *name, umode_t mode, 54 struct dentry *parent, void *data, 55 const struct file_operations *fops); 56 57 struct dentry *debugfs_create_file_size(const char *name, umode_t mode, 58 struct dentry *parent, void *data, 59 const struct file_operations *fops, 60 loff_t file_size); 61 62 struct dentry *debugfs_create_dir(const char *name, struct dentry *parent); 63 64 struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent, 65 const char *dest); 66 67 struct dentry *debugfs_create_automount(const char *name, 68 struct dentry *parent, 69 struct vfsmount *(*f)(void *), 70 void *data); 71 72 void debugfs_remove(struct dentry *dentry); 73 void debugfs_remove_recursive(struct dentry *dentry); 74 75 int debugfs_use_file_start(const struct dentry *dentry, int *srcu_idx) 76 __acquires(&debugfs_srcu); 77 78 void debugfs_use_file_finish(int srcu_idx) __releases(&debugfs_srcu); 79 80 ssize_t debugfs_attr_read(struct file *file, char __user *buf, 81 size_t len, loff_t *ppos); 82 ssize_t debugfs_attr_write(struct file *file, const char __user *buf, 83 size_t len, loff_t *ppos); 84 85 #define DEFINE_DEBUGFS_ATTRIBUTE(__fops, __get, __set, __fmt) \ 86 static int __fops ## _open(struct inode *inode, struct file *file) \ 87 { \ 88 __simple_attr_check_format(__fmt, 0ull); \ 89 return simple_attr_open(inode, file, __get, __set, __fmt); \ 90 } \ 91 static const struct file_operations __fops = { \ 92 .owner = THIS_MODULE, \ 93 .open = __fops ## _open, \ 94 .release = simple_attr_release, \ 95 .read = debugfs_attr_read, \ 96 .write = debugfs_attr_write, \ 97 .llseek = generic_file_llseek, \ 98 } 99 100 struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry, 101 struct dentry *new_dir, const char *new_name); 102 103 struct dentry *debugfs_create_u8(const char *name, umode_t mode, 104 struct dentry *parent, u8 *value); 105 struct dentry *debugfs_create_u16(const char *name, umode_t mode, 106 struct dentry *parent, u16 *value); 107 struct dentry *debugfs_create_u32(const char *name, umode_t mode, 108 struct dentry *parent, u32 *value); 109 struct dentry *debugfs_create_u64(const char *name, umode_t mode, 110 struct dentry *parent, u64 *value); 111 struct dentry *debugfs_create_ulong(const char *name, umode_t mode, 112 struct dentry *parent, unsigned long *value); 113 struct dentry *debugfs_create_x8(const char *name, umode_t mode, 114 struct dentry *parent, u8 *value); 115 struct dentry *debugfs_create_x16(const char *name, umode_t mode, 116 struct dentry *parent, u16 *value); 117 struct dentry *debugfs_create_x32(const char *name, umode_t mode, 118 struct dentry *parent, u32 *value); 119 struct dentry *debugfs_create_x64(const char *name, umode_t mode, 120 struct dentry *parent, u64 *value); 121 struct dentry *debugfs_create_size_t(const char *name, umode_t mode, 122 struct dentry *parent, size_t *value); 123 struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode, 124 struct dentry *parent, atomic_t *value); 125 struct dentry *debugfs_create_bool(const char *name, umode_t mode, 126 struct dentry *parent, bool *value); 127 128 struct dentry *debugfs_create_blob(const char *name, umode_t mode, 129 struct dentry *parent, 130 struct debugfs_blob_wrapper *blob); 131 132 struct dentry *debugfs_create_regset32(const char *name, umode_t mode, 133 struct dentry *parent, 134 struct debugfs_regset32 *regset); 135 136 void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs, 137 int nregs, void __iomem *base, char *prefix); 138 139 struct dentry *debugfs_create_u32_array(const char *name, umode_t mode, 140 struct dentry *parent, 141 u32 *array, u32 elements); 142 143 struct dentry *debugfs_create_devm_seqfile(struct device *dev, const char *name, 144 struct dentry *parent, 145 int (*read_fn)(struct seq_file *s, 146 void *data)); 147 148 bool debugfs_initialized(void); 149 150 ssize_t debugfs_read_file_bool(struct file *file, char __user *user_buf, 151 size_t count, loff_t *ppos); 152 153 ssize_t debugfs_write_file_bool(struct file *file, const char __user *user_buf, 154 size_t count, loff_t *ppos); 155 156 #else 157 158 #include <linux/err.h> 159 160 /* 161 * We do not return NULL from these functions if CONFIG_DEBUG_FS is not enabled 162 * so users have a chance to detect if there was a real error or not. We don't 163 * want to duplicate the design decision mistakes of procfs and devfs again. 164 */ 165 166 static inline struct dentry *debugfs_create_file(const char *name, umode_t mode, 167 struct dentry *parent, void *data, 168 const struct file_operations *fops) 169 { 170 return ERR_PTR(-ENODEV); 171 } 172 173 static inline struct dentry *debugfs_create_file_size(const char *name, umode_t mode, 174 struct dentry *parent, void *data, 175 const struct file_operations *fops, 176 loff_t file_size) 177 { 178 return ERR_PTR(-ENODEV); 179 } 180 181 static inline struct dentry *debugfs_create_dir(const char *name, 182 struct dentry *parent) 183 { 184 return ERR_PTR(-ENODEV); 185 } 186 187 static inline struct dentry *debugfs_create_symlink(const char *name, 188 struct dentry *parent, 189 const char *dest) 190 { 191 return ERR_PTR(-ENODEV); 192 } 193 194 static inline struct dentry *debugfs_create_automount(const char *name, 195 struct dentry *parent, 196 struct vfsmount *(*f)(void *), 197 void *data) 198 { 199 return ERR_PTR(-ENODEV); 200 } 201 202 static inline void debugfs_remove(struct dentry *dentry) 203 { } 204 205 static inline void debugfs_remove_recursive(struct dentry *dentry) 206 { } 207 208 static inline int debugfs_use_file_start(const struct dentry *dentry, 209 int *srcu_idx) 210 __acquires(&debugfs_srcu) 211 { 212 return 0; 213 } 214 215 static inline void debugfs_use_file_finish(int srcu_idx) 216 __releases(&debugfs_srcu) 217 { } 218 219 #define DEFINE_DEBUGFS_ATTRIBUTE(__fops, __get, __set, __fmt) \ 220 static const struct file_operations __fops = { 0 } 221 222 static inline struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry, 223 struct dentry *new_dir, char *new_name) 224 { 225 return ERR_PTR(-ENODEV); 226 } 227 228 static inline struct dentry *debugfs_create_u8(const char *name, umode_t mode, 229 struct dentry *parent, 230 u8 *value) 231 { 232 return ERR_PTR(-ENODEV); 233 } 234 235 static inline struct dentry *debugfs_create_u16(const char *name, umode_t mode, 236 struct dentry *parent, 237 u16 *value) 238 { 239 return ERR_PTR(-ENODEV); 240 } 241 242 static inline struct dentry *debugfs_create_u32(const char *name, umode_t mode, 243 struct dentry *parent, 244 u32 *value) 245 { 246 return ERR_PTR(-ENODEV); 247 } 248 249 static inline struct dentry *debugfs_create_u64(const char *name, umode_t mode, 250 struct dentry *parent, 251 u64 *value) 252 { 253 return ERR_PTR(-ENODEV); 254 } 255 256 static inline struct dentry *debugfs_create_x8(const char *name, umode_t mode, 257 struct dentry *parent, 258 u8 *value) 259 { 260 return ERR_PTR(-ENODEV); 261 } 262 263 static inline struct dentry *debugfs_create_x16(const char *name, umode_t mode, 264 struct dentry *parent, 265 u16 *value) 266 { 267 return ERR_PTR(-ENODEV); 268 } 269 270 static inline struct dentry *debugfs_create_x32(const char *name, umode_t mode, 271 struct dentry *parent, 272 u32 *value) 273 { 274 return ERR_PTR(-ENODEV); 275 } 276 277 static inline struct dentry *debugfs_create_x64(const char *name, umode_t mode, 278 struct dentry *parent, 279 u64 *value) 280 { 281 return ERR_PTR(-ENODEV); 282 } 283 284 static inline struct dentry *debugfs_create_size_t(const char *name, umode_t mode, 285 struct dentry *parent, 286 size_t *value) 287 { 288 return ERR_PTR(-ENODEV); 289 } 290 291 static inline struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode, 292 struct dentry *parent, atomic_t *value) 293 { 294 return ERR_PTR(-ENODEV); 295 } 296 297 static inline struct dentry *debugfs_create_bool(const char *name, umode_t mode, 298 struct dentry *parent, 299 bool *value) 300 { 301 return ERR_PTR(-ENODEV); 302 } 303 304 static inline struct dentry *debugfs_create_blob(const char *name, umode_t mode, 305 struct dentry *parent, 306 struct debugfs_blob_wrapper *blob) 307 { 308 return ERR_PTR(-ENODEV); 309 } 310 311 static inline struct dentry *debugfs_create_regset32(const char *name, 312 umode_t mode, struct dentry *parent, 313 struct debugfs_regset32 *regset) 314 { 315 return ERR_PTR(-ENODEV); 316 } 317 318 static inline void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs, 319 int nregs, void __iomem *base, char *prefix) 320 { 321 } 322 323 static inline bool debugfs_initialized(void) 324 { 325 return false; 326 } 327 328 static inline struct dentry *debugfs_create_u32_array(const char *name, umode_t mode, 329 struct dentry *parent, 330 u32 *array, u32 elements) 331 { 332 return ERR_PTR(-ENODEV); 333 } 334 335 static inline struct dentry *debugfs_create_devm_seqfile(struct device *dev, 336 const char *name, 337 struct dentry *parent, 338 int (*read_fn)(struct seq_file *s, 339 void *data)) 340 { 341 return ERR_PTR(-ENODEV); 342 } 343 344 static inline ssize_t debugfs_read_file_bool(struct file *file, 345 char __user *user_buf, 346 size_t count, loff_t *ppos) 347 { 348 return -ENODEV; 349 } 350 351 static inline ssize_t debugfs_write_file_bool(struct file *file, 352 const char __user *user_buf, 353 size_t count, loff_t *ppos) 354 { 355 return -ENODEV; 356 } 357 358 #endif 359 360 #endif 361