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 <linux/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         const void *(*namespace)(struct kobject *, const struct attribute *);
 116 };
 117
 118 struct sysfs_dirent;
 119
 120 #ifdef CONFIG_SYSFS
 121
 122 int sysfs_schedule_callback(struct kobject *kobj, void (*func)(void *),
 123                             void *data, struct module *owner);
 124
 125 int __must_check sysfs_create_dir(struct kobject *kobj);
 126 void sysfs_remove_dir(struct kobject *kobj);
 127 int __must_check sysfs_rename_dir(struct kobject *kobj, const char *new_name);
 128 int __must_check sysfs_move_dir(struct kobject *kobj,
 129                                 struct kobject *new_parent_kobj);
 130
 131 int __must_check sysfs_create_file(struct kobject *kobj,
 132                                    const struct attribute *attr);
 133 int __must_check sysfs_create_files(struct kobject *kobj,
 134                                    const struct attribute **attr);
 135 int __must_check sysfs_chmod_file(struct kobject *kobj,
 136                                   const struct attribute *attr, mode_t mode);
 137 void sysfs_remove_file(struct kobject *kobj, const struct attribute *attr);
 138 void sysfs_remove_files(struct kobject *kobj, const struct attribute **attr);
 139
 140 int __must_check sysfs_create_bin_file(struct kobject *kobj,
 141                                        const struct bin_attribute *attr);
 142 void sysfs_remove_bin_file(struct kobject *kobj,
 143                            const struct bin_attribute *attr);
 144
 145 int __must_check sysfs_create_link(struct kobject *kobj, struct kobject *target,
 146                                    const char *name);
 147 int __must_check sysfs_create_link_nowarn(struct kobject *kobj,
 148                                           struct kobject *target,
 149                                           const char *name);
 150 void sysfs_remove_link(struct kobject *kobj, const char *name);
 151
 152 int sysfs_rename_link(struct kobject *kobj, struct kobject *target,
 153                         const char *old_name, const char *new_name);
 154
 155 void sysfs_delete_link(struct kobject *dir, struct kobject *targ,
 156                         const char *name);
 157
 158 int __must_check sysfs_create_group(struct kobject *kobj,
 159                                     const struct attribute_group *grp);
 160 int sysfs_update_group(struct kobject *kobj,
 161                        const struct attribute_group *grp);
 162 void sysfs_remove_group(struct kobject *kobj,
 163                         const struct attribute_group *grp);
 164 int sysfs_add_file_to_group(struct kobject *kobj,
 165                         const struct attribute *attr, const char *group);
 166 void sysfs_remove_file_from_group(struct kobject *kobj,
 167                         const struct attribute *attr, const char *group);
 168 int sysfs_merge_group(struct kobject *kobj,
 169                        const struct attribute_group *grp);
 170 void sysfs_unmerge_group(struct kobject *kobj,
 171                        const struct attribute_group *grp);
 172
 173 void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr);
 174 void sysfs_notify_dirent(struct sysfs_dirent *sd);
 175 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
 176                                       const void *ns,
 177                                       const unsigned char *name);
 178 struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd);
 179 void sysfs_put(struct sysfs_dirent *sd);
 180
 181 int __must_check sysfs_init(void);
 182
 183 #else /* CONFIG_SYSFS */
 184
 185 static inline int sysfs_schedule_callback(struct kobject *kobj,
 186                 void (*func)(void *), void *data, struct module *owner)
 187 {
 188         return -ENOSYS;
 189 }
 190
 191 static inline int sysfs_create_dir(struct kobject *kobj)
 192 {
 193         return 0;
 194 }
 195
 196 static inline void sysfs_remove_dir(struct kobject *kobj)
 197 {
 198 }
 199
 200 static inline int sysfs_rename_dir(struct kobject *kobj, const char *new_name)
 201 {
 202         return 0;
 203 }
 204
 205 static inline int sysfs_move_dir(struct kobject *kobj,
 206                                  struct kobject *new_parent_kobj)
 207 {
 208         return 0;
 209 }
 210
 211 static inline int sysfs_create_file(struct kobject *kobj,
 212                                     const struct attribute *attr)
 213 {
 214         return 0;
 215 }
 216
 217 static inline int sysfs_create_files(struct kobject *kobj,
 218                                     const struct attribute **attr)
 219 {
 220         return 0;
 221 }
 222
 223 static inline int sysfs_chmod_file(struct kobject *kobj,
 224                                    const struct attribute *attr, mode_t mode)
 225 {
 226         return 0;
 227 }
 228
 229 static inline void sysfs_remove_file(struct kobject *kobj,
 230                                      const struct attribute *attr)
 231 {
 232 }
 233
 234 static inline void sysfs_remove_files(struct kobject *kobj,
 235                                      const struct attribute **attr)
 236 {
 237 }
 238
 239 static inline int sysfs_create_bin_file(struct kobject *kobj,
 240                                         const struct bin_attribute *attr)
 241 {
 242         return 0;
 243 }
 244
 245 static inline void sysfs_remove_bin_file(struct kobject *kobj,
 246                                          const struct bin_attribute *attr)
 247 {
 248 }
 249
 250 static inline int sysfs_create_link(struct kobject *kobj,
 251                                     struct kobject *target, const char *name)
 252 {
 253         return 0;
 254 }
 255
 256 static inline int sysfs_create_link_nowarn(struct kobject *kobj,
 257                                            struct kobject *target,
 258                                            const char *name)
 259 {
 260         return 0;
 261 }
 262
 263 static inline void sysfs_remove_link(struct kobject *kobj, const char *name)
 264 {
 265 }
 266
 267 static inline int sysfs_rename_link(struct kobject *k, struct kobject *t,
 268                                     const char *old_name, const char *new_name)
 269 {
 270         return 0;
 271 }
 272
 273 static inline void sysfs_delete_link(struct kobject *k, struct kobject *t,
 274                                      const char *name)
 275 {
 276 }
 277
 278 static inline int sysfs_create_group(struct kobject *kobj,
 279                                      const struct attribute_group *grp)
 280 {
 281         return 0;
 282 }
 283
 284 static inline int sysfs_update_group(struct kobject *kobj,
 285                                 const struct attribute_group *grp)
 286 {
 287         return 0;
 288 }
 289
 290 static inline void sysfs_remove_group(struct kobject *kobj,
 291                                       const struct attribute_group *grp)
 292 {
 293 }
 294
 295 static inline int sysfs_add_file_to_group(struct kobject *kobj,
 296                 const struct attribute *attr, const char *group)
 297 {
 298         return 0;
 299 }
 300
 301 static inline void sysfs_remove_file_from_group(struct kobject *kobj,
 302                 const struct attribute *attr, const char *group)
 303 {
 304 }
 305
 306 static inline int sysfs_merge_group(struct kobject *kobj,
 307                        const struct attribute_group *grp)
 308 {
 309         return 0;
 310 }
 311
 312 static inline void sysfs_unmerge_group(struct kobject *kobj,
 313                        const struct attribute_group *grp)
 314 {
 315 }
 316
 317 static inline void sysfs_notify(struct kobject *kobj, const char *dir,
 318                                 const char *attr)
 319 {
 320 }
 321 static inline void sysfs_notify_dirent(struct sysfs_dirent *sd)
 322 {
 323 }
 324 static inline
 325 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
 326                                       const void *ns,
 327                                       const unsigned char *name)
 328 {
 329         return NULL;
 330 }
 331 static inline struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd)
 332 {
 333         return NULL;
 334 }
 335 static inline void sysfs_put(struct sysfs_dirent *sd)
 336 {
 337 }
 338
 339 static inline int __must_check sysfs_init(void)
 340 {
 341         return 0;
 342 }
 343
 344 #endif /* CONFIG_SYSFS */
 345
 346 #endif /* _SYSFS_H_ */