include/linux/sysfs.h

   1 /*
   2  * sysfs.h - definitions for the device driver filesystem
   3  *
   4  * Copyright (c) 2001,2002 Patrick Mochel
   5  * Copyright (c) 2004 Silicon Graphics, Inc.
   6  * Copyright (c) 2007 SUSE Linux Products GmbH
   7  * Copyright (c) 2007 Tejun Heo <teheo@suse.de>
   8  *
   9  * Please see Documentation/filesystems/sysfs.txt for more information.
  10  */
  11
  12 #ifndef _SYSFS_H_
  13 #define _SYSFS_H_
  14
  15 #include <linux/compiler.h>
  16 #include <linux/errno.h>
  17 #include <linux/list.h>
  18 #include <linux/lockdep.h>
  19 #include <linux/kobject_ns.h>
  20 #include <asm/atomic.h>
  21
  22 struct kobject;
  23 struct module;
  24 enum kobj_ns_type;
  25
  26 struct attribute {
  27         const char              *name;
  28         mode_t                  mode;
  29 #ifdef CONFIG_DEBUG_LOCK_ALLOC
  30         struct lock_class_key   *key;
  31         struct lock_class_key   skey;
  32 #endif
  33 };
  34
  35 /**
  36  *      sysfs_attr_init - initialize a dynamically allocated sysfs attribute
  37  *      @attr: struct attribute to initialize
  38  *
  39  *      Initialize a dynamically allocated struct attribute so we can
  40  *      make lockdep happy.  This is a new requirement for attributes
  41  *      and initially this is only needed when lockdep is enabled.
  42  *      Lockdep gives a nice error when your attribute is added to
  43  *      sysfs if you don't have this.
  44  */
  45 #ifdef CONFIG_DEBUG_LOCK_ALLOC
  46 #define sysfs_attr_init(attr)                           \
  47 do {                                                    \
  48         static struct lock_class_key __key;             \
  49                                                         \
  50         (attr)->key = &__key;                           \
  51 } while(0)
  52 #else
  53 #define sysfs_attr_init(attr) do {} while(0)
  54 #endif
  55
  56 struct attribute_group {
  57         const char              *name;
  58         mode_t                  (*is_visible)(struct kobject *,
  59                                               struct attribute *, int);
  60         struct attribute        **attrs;
  61 };
  62
  63
  64
  65 /**
  66  * Use these macros to make defining attributes easier. See include/linux/device.h
  67  * for examples..
  68  */
  69
  70 #define __ATTR(_name,_mode,_show,_store) { \
  71         .attr = {.name = __stringify(_name), .mode = _mode },   \
  72         .show   = _show,                                        \
  73         .store  = _store,                                       \
  74 }
  75
  76 #define __ATTR_RO(_name) { \
  77         .attr   = { .name = __stringify(_name), .mode = 0444 }, \
  78         .show   = _name##_show,                                 \
  79 }
  80
  81 #define __ATTR_NULL { .attr = { .name = NULL } }
  82
  83 #define attr_name(_attr) (_attr).attr.name
  84
  85 struct file;
  86 struct vm_area_struct;
  87
  88 struct bin_attribute {
  89         struct attribute        attr;
  90         size_t                  size;
  91         void                    *private;
  92         ssize_t (*read)(struct file *, struct kobject *, struct bin_attribute *,
  93                         char *, loff_t, size_t);
  94         ssize_t (*write)(struct file *,struct kobject *, struct bin_attribute *,
  95                          char *, loff_t, size_t);
  96         int (*mmap)(struct file *, struct kobject *, struct bin_attribute *attr,
  97                     struct vm_area_struct *vma);
  98 };
  99
 100 /**
 101  *      sysfs_bin_attr_init - initialize a dynamically allocated bin_attribute
 102  *      @attr: struct bin_attribute to initialize
 103  *
 104  *      Initialize a dynamically allocated struct bin_attribute so we
 105  *      can make lockdep happy.  This is a new requirement for
 106  *      attributes and initially this is only needed when lockdep is
 107  *      enabled.  Lockdep gives a nice error when your attribute is
 108  *      added to sysfs if you don't have this.
 109  */
 110 #define sysfs_bin_attr_init(bin_attr) sysfs_attr_init(&(bin_attr)->attr)
 111
 112 struct sysfs_ops {
 113         ssize_t (*show)(struct kobject *, struct attribute *,char *);
 114         ssize_t (*store)(struct kobject *,struct attribute *,const char *, size_t);
 115 };
 116
 117 struct sysfs_dirent;
 118
 119 #ifdef CONFIG_SYSFS
 120
 121 int sysfs_schedule_callback(struct kobject *kobj, void (*func)(void *),
 122                             void *data, struct module *owner);
 123
 124 int __must_check sysfs_create_dir(struct kobject *kobj);
 125 void sysfs_remove_dir(struct kobject *kobj);
 126 int __must_check sysfs_rename_dir(struct kobject *kobj, const char *new_name);
 127 int __must_check sysfs_move_dir(struct kobject *kobj,
 128                                 struct kobject *new_parent_kobj);
 129
 130 int __must_check sysfs_create_file(struct kobject *kobj,
 131                                    const struct attribute *attr);
 132 int __must_check sysfs_create_files(struct kobject *kobj,
 133                                    const struct attribute **attr);
 134 int __must_check sysfs_chmod_file(struct kobject *kobj,
 135                                   const struct attribute *attr, mode_t mode);
 136 void sysfs_remove_file(struct kobject *kobj, const struct attribute *attr);
 137 void sysfs_remove_files(struct kobject *kobj, const struct attribute **attr);
 138
 139 int __must_check sysfs_create_bin_file(struct kobject *kobj,
 140                                        const struct bin_attribute *attr);
 141 void sysfs_remove_bin_file(struct kobject *kobj,
 142                            const struct bin_attribute *attr);
 143
 144 int __must_check sysfs_create_link(struct kobject *kobj, struct kobject *target,
 145                                    const char *name);
 146 int __must_check sysfs_create_link_nowarn(struct kobject *kobj,
 147                                           struct kobject *target,
 148                                           const char *name);
 149 void sysfs_remove_link(struct kobject *kobj, const char *name);
 150
 151 int sysfs_rename_link(struct kobject *kobj, struct kobject *target,
 152                         const char *old_name, const char *new_name);
 153
 154 void sysfs_delete_link(struct kobject *dir, struct kobject *targ,
 155                         const char *name);
 156
 157 int __must_check sysfs_create_group(struct kobject *kobj,
 158                                     const struct attribute_group *grp);
 159 int sysfs_update_group(struct kobject *kobj,
 160                        const struct attribute_group *grp);
 161 void sysfs_remove_group(struct kobject *kobj,
 162                         const struct attribute_group *grp);
 163 int sysfs_add_file_to_group(struct kobject *kobj,
 164                         const struct attribute *attr, const char *group);
 165 void sysfs_remove_file_from_group(struct kobject *kobj,
 166                         const struct attribute *attr, const char *group);
 167 int sysfs_merge_group(struct kobject *kobj,
 168                        const struct attribute_group *grp);
 169 void sysfs_unmerge_group(struct kobject *kobj,
 170                        const struct attribute_group *grp);
 171
 172 void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr);
 173 void sysfs_notify_dirent(struct sysfs_dirent *sd);
 174 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
 175                                       const void *ns,
 176                                       const unsigned char *name);
 177 struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd);
 178 void sysfs_put(struct sysfs_dirent *sd);
 179
 180 /* Called to clear a ns tag when it is no longer valid */
 181 void sysfs_exit_ns(enum kobj_ns_type type, const void *tag);
 182
 183 int __must_check sysfs_init(void);
 184
 185 #else /* CONFIG_SYSFS */
 186
 187 static inline int sysfs_schedule_callback(struct kobject *kobj,
 188                 void (*func)(void *), void *data, struct module *owner)
 189 {
 190         return -ENOSYS;
 191 }
 192
 193 static inline int sysfs_create_dir(struct kobject *kobj)
 194 {
 195         return 0;
 196 }
 197
 198 static inline void sysfs_remove_dir(struct kobject *kobj)
 199 {
 200 }
 201
 202 static inline int sysfs_rename_dir(struct kobject *kobj, const char *new_name)
 203 {
 204         return 0;
 205 }
 206
 207 static inline int sysfs_move_dir(struct kobject *kobj,
 208                                  struct kobject *new_parent_kobj)
 209 {
 210         return 0;
 211 }
 212
 213 static inline int sysfs_create_file(struct kobject *kobj,
 214                                     const struct attribute *attr)
 215 {
 216         return 0;
 217 }
 218
 219 static inline int sysfs_create_files(struct kobject *kobj,
 220                                     const struct attribute **attr)
 221 {
 222         return 0;
 223 }
 224
 225 static inline int sysfs_chmod_file(struct kobject *kobj,
 226                                    const struct attribute *attr, mode_t mode)
 227 {
 228         return 0;
 229 }
 230
 231 static inline void sysfs_remove_file(struct kobject *kobj,
 232                                      const struct attribute *attr)
 233 {
 234 }
 235
 236 static inline void sysfs_remove_files(struct kobject *kobj,
 237                                      const struct attribute **attr)
 238 {
 239 }
 240
 241 static inline int sysfs_create_bin_file(struct kobject *kobj,
 242                                         const struct bin_attribute *attr)
 243 {
 244         return 0;
 245 }
 246
 247 static inline void sysfs_remove_bin_file(struct kobject *kobj,
 248                                          const struct bin_attribute *attr)
 249 {
 250 }
 251
 252 static inline int sysfs_create_link(struct kobject *kobj,
 253                                     struct kobject *target, const char *name)
 254 {
 255         return 0;
 256 }
 257
 258 static inline int sysfs_create_link_nowarn(struct kobject *kobj,
 259                                            struct kobject *target,
 260                                            const char *name)
 261 {
 262         return 0;
 263 }
 264
 265 static inline void sysfs_remove_link(struct kobject *kobj, const char *name)
 266 {
 267 }
 268
 269 static inline int sysfs_rename_link(struct kobject *k, struct kobject *t,
 270                                     const char *old_name, const char *new_name)
 271 {
 272         return 0;
 273 }
 274
 275 static inline void sysfs_delete_link(struct kobject *k, struct kobject *t,
 276                                      const char *name)
 277 {
 278 }
 279
 280 static inline int sysfs_create_group(struct kobject *kobj,
 281                                      const struct attribute_group *grp)
 282 {
 283         return 0;
 284 }
 285
 286 static inline int sysfs_update_group(struct kobject *kobj,
 287                                 const struct attribute_group *grp)
 288 {
 289         return 0;
 290 }
 291
 292 static inline void sysfs_remove_group(struct kobject *kobj,
 293                                       const struct attribute_group *grp)
 294 {
 295 }
 296
 297 static inline int sysfs_add_file_to_group(struct kobject *kobj,
 298                 const struct attribute *attr, const char *group)
 299 {
 300         return 0;
 301 }
 302
 303 static inline void sysfs_remove_file_from_group(struct kobject *kobj,
 304                 const struct attribute *attr, const char *group)
 305 {
 306 }
 307
 308 static inline int sysfs_merge_group(struct kobject *kobj,
 309                        const struct attribute_group *grp)
 310 {
 311         return 0;
 312 }
 313
 314 static inline void sysfs_unmerge_group(struct kobject *kobj,
 315                        const struct attribute_group *grp)
 316 {
 317 }
 318
 319 static inline void sysfs_notify(struct kobject *kobj, const char *dir,
 320                                 const char *attr)
 321 {
 322 }
 323 static inline void sysfs_notify_dirent(struct sysfs_dirent *sd)
 324 {
 325 }
 326 static inline
 327 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
 328                                       const void *ns,
 329                                       const unsigned char *name)
 330 {
 331         return NULL;
 332 }
 333 static inline struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd)
 334 {
 335         return NULL;
 336 }
 337 static inline void sysfs_put(struct sysfs_dirent *sd)
 338 {
 339 }
 340
 341 static inline void sysfs_exit_ns(int type, const void *tag)
 342 {
 343 }
 344
 345 static inline int __must_check sysfs_init(void)
 346 {
 347         return 0;
 348 }
 349
 350 #endif /* CONFIG_SYSFS */
 351
 352 #endif /* _SYSFS_H_ */