include/linux/debugfs.h

   1 /*
   2  *  debugfs.h - a tiny little debug file system
   3  *
   4  *  Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
   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
  23 struct device;
  24 struct file_operations;
  25
  26 struct debugfs_blob_wrapper {
  27         void *data;
  28         unsigned long size;
  29 };
  30
  31 struct debugfs_reg32 {
  32         char *name;
  33         unsigned long offset;
  34 };
  35
  36 struct debugfs_regset32 {
  37         const struct debugfs_reg32 *regs;
  38         int nregs;
  39         void __iomem *base;
  40 };
  41
  42 extern struct dentry *arch_debugfs_dir;
  43
  44 #if defined(CONFIG_DEBUG_FS)
  45
  46 /* declared over in file.c */
  47 extern const struct file_operations debugfs_file_operations;
  48
  49 struct dentry *debugfs_create_file(const char *name, umode_t mode,
  50                                    struct dentry *parent, void *data,
  51                                    const struct file_operations *fops);
  52
  53 struct dentry *debugfs_create_file_size(const char *name, umode_t mode,
  54                                         struct dentry *parent, void *data,
  55                                         const struct file_operations *fops,
  56                                         loff_t file_size);
  57
  58 struct dentry *debugfs_create_dir(const char *name, struct dentry *parent);
  59
  60 struct dentry *debugfs_create_symlink(const char *name, struct dentry *parent,
  61                                       const char *dest);
  62
  63 struct dentry *debugfs_create_automount(const char *name,
  64                                         struct dentry *parent,
  65                                         struct vfsmount *(*f)(void *),
  66                                         void *data);
  67
  68 void debugfs_remove(struct dentry *dentry);
  69 void debugfs_remove_recursive(struct dentry *dentry);
  70
  71 struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
  72                 struct dentry *new_dir, const char *new_name);
  73
  74 struct dentry *debugfs_create_u8(const char *name, umode_t mode,
  75                                  struct dentry *parent, u8 *value);
  76 struct dentry *debugfs_create_u16(const char *name, umode_t mode,
  77                                   struct dentry *parent, u16 *value);
  78 struct dentry *debugfs_create_u32(const char *name, umode_t mode,
  79                                   struct dentry *parent, u32 *value);
  80 struct dentry *debugfs_create_u64(const char *name, umode_t mode,
  81                                   struct dentry *parent, u64 *value);
  82 struct dentry *debugfs_create_x8(const char *name, umode_t mode,
  83                                  struct dentry *parent, u8 *value);
  84 struct dentry *debugfs_create_x16(const char *name, umode_t mode,
  85                                   struct dentry *parent, u16 *value);
  86 struct dentry *debugfs_create_x32(const char *name, umode_t mode,
  87                                   struct dentry *parent, u32 *value);
  88 struct dentry *debugfs_create_x64(const char *name, umode_t mode,
  89                                   struct dentry *parent, u64 *value);
  90 struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
  91                                      struct dentry *parent, size_t *value);
  92 struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
  93                                      struct dentry *parent, atomic_t *value);
  94 struct dentry *debugfs_create_bool(const char *name, umode_t mode,
  95                                   struct dentry *parent, u32 *value);
  96
  97 struct dentry *debugfs_create_blob(const char *name, umode_t mode,
  98                                   struct dentry *parent,
  99                                   struct debugfs_blob_wrapper *blob);
 100
 101 struct dentry *debugfs_create_regset32(const char *name, umode_t mode,
 102                                      struct dentry *parent,
 103                                      struct debugfs_regset32 *regset);
 104
 105 void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
 106                           int nregs, void __iomem *base, char *prefix);
 107
 108 struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
 109                                         struct dentry *parent,
 110                                         u32 *array, u32 elements);
 111
 112 struct dentry *debugfs_create_devm_seqfile(struct device *dev, const char *name,
 113                                            struct dentry *parent,
 114                                            int (*read_fn)(struct seq_file *s,
 115                                                           void *data));
 116
 117 bool debugfs_initialized(void);
 118
 119 ssize_t debugfs_read_file_bool(struct file *file, char __user *user_buf,
 120                                size_t count, loff_t *ppos);
 121
 122 ssize_t debugfs_write_file_bool(struct file *file, const char __user *user_buf,
 123                                 size_t count, loff_t *ppos);
 124
 125 #else
 126
 127 #include <linux/err.h>
 128
 129 /*
 130  * We do not return NULL from these functions if CONFIG_DEBUG_FS is not enabled
 131  * so users have a chance to detect if there was a real error or not.  We don't
 132  * want to duplicate the design decision mistakes of procfs and devfs again.
 133  */
 134
 135 static inline struct dentry *debugfs_create_file(const char *name, umode_t mode,
 136                                         struct dentry *parent, void *data,
 137                                         const struct file_operations *fops)
 138 {
 139         return ERR_PTR(-ENODEV);
 140 }
 141
 142 static inline struct dentry *debugfs_create_file_size(const char *name, umode_t mode,
 143                                         struct dentry *parent, void *data,
 144                                         const struct file_operations *fops,
 145                                         loff_t file_size)
 146 {
 147         return ERR_PTR(-ENODEV);
 148 }
 149
 150 static inline struct dentry *debugfs_create_dir(const char *name,
 151                                                 struct dentry *parent)
 152 {
 153         return ERR_PTR(-ENODEV);
 154 }
 155
 156 static inline struct dentry *debugfs_create_symlink(const char *name,
 157                                                     struct dentry *parent,
 158                                                     const char *dest)
 159 {
 160         return ERR_PTR(-ENODEV);
 161 }
 162
 163 static inline void debugfs_remove(struct dentry *dentry)
 164 { }
 165
 166 static inline void debugfs_remove_recursive(struct dentry *dentry)
 167 { }
 168
 169 static inline struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
 170                 struct dentry *new_dir, char *new_name)
 171 {
 172         return ERR_PTR(-ENODEV);
 173 }
 174
 175 static inline struct dentry *debugfs_create_u8(const char *name, umode_t mode,
 176                                                struct dentry *parent,
 177                                                u8 *value)
 178 {
 179         return ERR_PTR(-ENODEV);
 180 }
 181
 182 static inline struct dentry *debugfs_create_u16(const char *name, umode_t mode,
 183                                                 struct dentry *parent,
 184                                                 u16 *value)
 185 {
 186         return ERR_PTR(-ENODEV);
 187 }
 188
 189 static inline struct dentry *debugfs_create_u32(const char *name, umode_t mode,
 190                                                 struct dentry *parent,
 191                                                 u32 *value)
 192 {
 193         return ERR_PTR(-ENODEV);
 194 }
 195
 196 static inline struct dentry *debugfs_create_u64(const char *name, umode_t mode,
 197                                                 struct dentry *parent,
 198                                                 u64 *value)
 199 {
 200         return ERR_PTR(-ENODEV);
 201 }
 202
 203 static inline struct dentry *debugfs_create_x8(const char *name, umode_t mode,
 204                                                struct dentry *parent,
 205                                                u8 *value)
 206 {
 207         return ERR_PTR(-ENODEV);
 208 }
 209
 210 static inline struct dentry *debugfs_create_x16(const char *name, umode_t mode,
 211                                                 struct dentry *parent,
 212                                                 u16 *value)
 213 {
 214         return ERR_PTR(-ENODEV);
 215 }
 216
 217 static inline struct dentry *debugfs_create_x32(const char *name, umode_t mode,
 218                                                 struct dentry *parent,
 219                                                 u32 *value)
 220 {
 221         return ERR_PTR(-ENODEV);
 222 }
 223
 224 static inline struct dentry *debugfs_create_x64(const char *name, umode_t mode,
 225                                                 struct dentry *parent,
 226                                                 u64 *value)
 227 {
 228         return ERR_PTR(-ENODEV);
 229 }
 230
 231 static inline struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
 232                                      struct dentry *parent,
 233                                      size_t *value)
 234 {
 235         return ERR_PTR(-ENODEV);
 236 }
 237
 238 static inline struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
 239                                      struct dentry *parent, atomic_t *value)
 240 {
 241         return ERR_PTR(-ENODEV);
 242 }
 243
 244 static inline struct dentry *debugfs_create_bool(const char *name, umode_t mode,
 245                                                  struct dentry *parent,
 246                                                  u32 *value)
 247 {
 248         return ERR_PTR(-ENODEV);
 249 }
 250
 251 static inline struct dentry *debugfs_create_blob(const char *name, umode_t mode,
 252                                   struct dentry *parent,
 253                                   struct debugfs_blob_wrapper *blob)
 254 {
 255         return ERR_PTR(-ENODEV);
 256 }
 257
 258 static inline struct dentry *debugfs_create_regset32(const char *name,
 259                                    umode_t mode, struct dentry *parent,
 260                                    struct debugfs_regset32 *regset)
 261 {
 262         return ERR_PTR(-ENODEV);
 263 }
 264
 265 static inline void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
 266                          int nregs, void __iomem *base, char *prefix)
 267 {
 268 }
 269
 270 static inline bool debugfs_initialized(void)
 271 {
 272         return false;
 273 }
 274
 275 static inline struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
 276                                         struct dentry *parent,
 277                                         u32 *array, u32 elements)
 278 {
 279         return ERR_PTR(-ENODEV);
 280 }
 281
 282 static inline struct dentry *debugfs_create_devm_seqfile(struct device *dev,
 283                                                          const char *name,
 284                                                          struct dentry *parent,
 285                                            int (*read_fn)(struct seq_file *s,
 286                                                           void *data))
 287 {
 288         return ERR_PTR(-ENODEV);
 289 }
 290
 291 static inline ssize_t debugfs_read_file_bool(struct file *file,
 292                                              char __user *user_buf,
 293                                              size_t count, loff_t *ppos)
 294 {
 295         return -ENODEV;
 296 }
 297
 298 static inline ssize_t debugfs_write_file_bool(struct file *file,
 299                                               const char __user *user_buf,
 300                                               size_t count, loff_t *ppos)
 301 {
 302         return -ENODEV;
 303 }
 304
 305 #endif
 306
 307 #endif