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         umode_t                 mode;
  29 #ifdef CONFIG_DEBUG_LOCK_ALLOC
  30         bool                    ignore_lockdep:1;
  31         struct lock_class_key   *key;
  32         struct lock_class_key   skey;
  33 #endif
  34 };
  35
  36 /**
  37  *      sysfs_attr_init - initialize a dynamically allocated sysfs attribute
  38  *      @attr: struct attribute to initialize
  39  *
  40  *      Initialize a dynamically allocated struct attribute so we can
  41  *      make lockdep happy.  This is a new requirement for attributes
  42  *      and initially this is only needed when lockdep is enabled.
  43  *      Lockdep gives a nice error when your attribute is added to
  44  *      sysfs if you don't have this.
  45  */
  46 #ifdef CONFIG_DEBUG_LOCK_ALLOC
  47 #define sysfs_attr_init(attr)                           \
  48 do {                                                    \
  49         static struct lock_class_key __key;             \
  50                                                         \
  51         (attr)->key = &__key;                           \
  52 } while(0)
  53 #else
  54 #define sysfs_attr_init(attr) do {} while(0)
  55 #endif
  56
  57 struct attribute_group {
  58         const char              *name;
  59         umode_t                 (*is_visible)(struct kobject *,
  60                                               struct attribute *, int);
  61         struct attribute        **attrs;
  62 };
  63
  64
  65
  66 /**
  67  * Use these macros to make defining attributes easier. See include/linux/device.h
  68  * for examples..
  69  */
  70
  71 #define __ATTR(_name,_mode,_show,_store) { \
  72         .attr = {.name = __stringify(_name), .mode = _mode },   \
  73         .show   = _show,                                        \
  74         .store  = _store,                                       \
  75 }
  76
  77 #define __ATTR_RO(_name) { \
  78         .attr   = { .name = __stringify(_name), .mode = 0444 }, \
  79         .show   = _name##_show,                                 \
  80 }
  81
  82 #define __ATTR_NULL { .attr = { .name = NULL } }
  83
  84 #ifdef CONFIG_DEBUG_LOCK_ALLOC
  85 #define __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) {    \
  86         .attr = {.name = __stringify(_name), .mode = _mode,     \
  87                         .ignore_lockdep = true },               \
  88         .show           = _show,                                \
  89         .store          = _store,                               \
  90 }
  91 #else
  92 #define __ATTR_IGNORE_LOCKDEP   __ATTR
  93 #endif
  94
  95 #define attr_name(_attr) (_attr).attr.name
  96
  97 struct file;
  98 struct vm_area_struct;
  99
 100 struct bin_attribute {
 101         struct attribute        attr;
 102         size_t                  size;
 103         void                    *private;
 104         ssize_t (*read)(struct file *, struct kobject *, struct bin_attribute *,
 105                         char *, loff_t, size_t);
 106         ssize_t (*write)(struct file *,struct kobject *, struct bin_attribute *,
 107                          char *, loff_t, size_t);
 108         int (*mmap)(struct file *, struct kobject *, struct bin_attribute *attr,
 109                     struct vm_area_struct *vma);
 110 };
 111
 112 /**
 113  *      sysfs_bin_attr_init - initialize a dynamically allocated bin_attribute
 114  *      @attr: struct bin_attribute to initialize
 115  *
 116  *      Initialize a dynamically allocated struct bin_attribute so we
 117  *      can make lockdep happy.  This is a new requirement for
 118  *      attributes and initially this is only needed when lockdep is
 119  *      enabled.  Lockdep gives a nice error when your attribute is
 120  *      added to sysfs if you don't have this.
 121  */
 122 #define sysfs_bin_attr_init(bin_attr) sysfs_attr_init(&(bin_attr)->attr)
 123
 124 struct sysfs_ops {
 125         ssize_t (*show)(struct kobject *, struct attribute *,char *);
 126         ssize_t (*store)(struct kobject *,struct attribute *,const char *, size_t);
 127         const void *(*namespace)(struct kobject *, const struct attribute *);
 128 };
 129
 130 struct sysfs_dirent;
 131
 132 #ifdef CONFIG_SYSFS
 133
 134 int sysfs_schedule_callback(struct kobject *kobj, void (*func)(void *),
 135                             void *data, struct module *owner);
 136
 137 int __must_check sysfs_create_dir(struct kobject *kobj);
 138 void sysfs_remove_dir(struct kobject *kobj);
 139 int __must_check sysfs_rename_dir(struct kobject *kobj, const char *new_name);
 140 int __must_check sysfs_move_dir(struct kobject *kobj,
 141                                 struct kobject *new_parent_kobj);
 142
 143 int __must_check sysfs_create_file(struct kobject *kobj,
 144                                    const struct attribute *attr);
 145 int __must_check sysfs_create_files(struct kobject *kobj,
 146                                    const struct attribute **attr);
 147 int __must_check sysfs_chmod_file(struct kobject *kobj,
 148                                   const struct attribute *attr, umode_t mode);
 149 void sysfs_remove_file(struct kobject *kobj, const struct attribute *attr);
 150 void sysfs_remove_files(struct kobject *kobj, const struct attribute **attr);
 151
 152 int __must_check sysfs_create_bin_file(struct kobject *kobj,
 153                                        const struct bin_attribute *attr);
 154 void sysfs_remove_bin_file(struct kobject *kobj,
 155                            const struct bin_attribute *attr);
 156
 157 int __must_check sysfs_create_link(struct kobject *kobj, struct kobject *target,
 158                                    const char *name);
 159 int __must_check sysfs_create_link_nowarn(struct kobject *kobj,
 160                                           struct kobject *target,
 161                                           const char *name);
 162 void sysfs_remove_link(struct kobject *kobj, const char *name);
 163
 164 int sysfs_rename_link(struct kobject *kobj, struct kobject *target,
 165                         const char *old_name, const char *new_name);
 166
 167 void sysfs_delete_link(struct kobject *dir, struct kobject *targ,
 168                         const char *name);
 169
 170 int __must_check sysfs_create_group(struct kobject *kobj,
 171                                     const struct attribute_group *grp);
 172 int sysfs_update_group(struct kobject *kobj,
 173                        const struct attribute_group *grp);
 174 void sysfs_remove_group(struct kobject *kobj,
 175                         const struct attribute_group *grp);
 176 int sysfs_add_file_to_group(struct kobject *kobj,
 177                         const struct attribute *attr, const char *group);
 178 void sysfs_remove_file_from_group(struct kobject *kobj,
 179                         const struct attribute *attr, const char *group);
 180 int sysfs_merge_group(struct kobject *kobj,
 181                        const struct attribute_group *grp);
 182 void sysfs_unmerge_group(struct kobject *kobj,
 183                        const struct attribute_group *grp);
 184 int sysfs_add_link_to_group(struct kobject *kobj, const char *group_name,
 185                             struct kobject *target, const char *link_name);
 186 void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name,
 187                                   const char *link_name);
 188
 189 void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr);
 190 void sysfs_notify_dirent(struct sysfs_dirent *sd);
 191 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
 192                                       const void *ns,
 193                                       const unsigned char *name);
 194 struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd);
 195 void sysfs_put(struct sysfs_dirent *sd);
 196
 197 int __must_check sysfs_init(void);
 198
 199 #else /* CONFIG_SYSFS */
 200
 201 static inline int sysfs_schedule_callback(struct kobject *kobj,
 202                 void (*func)(void *), void *data, struct module *owner)
 203 {
 204         return -ENOSYS;
 205 }
 206
 207 static inline int sysfs_create_dir(struct kobject *kobj)
 208 {
 209         return 0;
 210 }
 211
 212 static inline void sysfs_remove_dir(struct kobject *kobj)
 213 {
 214 }
 215
 216 static inline int sysfs_rename_dir(struct kobject *kobj, const char *new_name)
 217 {
 218         return 0;
 219 }
 220
 221 static inline int sysfs_move_dir(struct kobject *kobj,
 222                                  struct kobject *new_parent_kobj)
 223 {
 224         return 0;
 225 }
 226
 227 static inline int sysfs_create_file(struct kobject *kobj,
 228                                     const struct attribute *attr)
 229 {
 230         return 0;
 231 }
 232
 233 static inline int sysfs_create_files(struct kobject *kobj,
 234                                     const struct attribute **attr)
 235 {
 236         return 0;
 237 }
 238
 239 static inline int sysfs_chmod_file(struct kobject *kobj,
 240                                    const struct attribute *attr, umode_t mode)
 241 {
 242         return 0;
 243 }
 244
 245 static inline void sysfs_remove_file(struct kobject *kobj,
 246                                      const struct attribute *attr)
 247 {
 248 }
 249
 250 static inline void sysfs_remove_files(struct kobject *kobj,
 251                                      const struct attribute **attr)
 252 {
 253 }
 254
 255 static inline int sysfs_create_bin_file(struct kobject *kobj,
 256                                         const struct bin_attribute *attr)
 257 {
 258         return 0;
 259 }
 260
 261 static inline void sysfs_remove_bin_file(struct kobject *kobj,
 262                                          const struct bin_attribute *attr)
 263 {
 264 }
 265
 266 static inline int sysfs_create_link(struct kobject *kobj,
 267                                     struct kobject *target, const char *name)
 268 {
 269         return 0;
 270 }
 271
 272 static inline int sysfs_create_link_nowarn(struct kobject *kobj,
 273                                            struct kobject *target,
 274                                            const char *name)
 275 {
 276         return 0;
 277 }
 278
 279 static inline void sysfs_remove_link(struct kobject *kobj, const char *name)
 280 {
 281 }
 282
 283 static inline int sysfs_rename_link(struct kobject *k, struct kobject *t,
 284                                     const char *old_name, const char *new_name)
 285 {
 286         return 0;
 287 }
 288
 289 static inline void sysfs_delete_link(struct kobject *k, struct kobject *t,
 290                                      const char *name)
 291 {
 292 }
 293
 294 static inline int sysfs_create_group(struct kobject *kobj,
 295                                      const struct attribute_group *grp)
 296 {
 297         return 0;
 298 }
 299
 300 static inline int sysfs_update_group(struct kobject *kobj,
 301                                 const struct attribute_group *grp)
 302 {
 303         return 0;
 304 }
 305
 306 static inline void sysfs_remove_group(struct kobject *kobj,
 307                                       const struct attribute_group *grp)
 308 {
 309 }
 310
 311 static inline int sysfs_add_file_to_group(struct kobject *kobj,
 312                 const struct attribute *attr, const char *group)
 313 {
 314         return 0;
 315 }
 316
 317 static inline void sysfs_remove_file_from_group(struct kobject *kobj,
 318                 const struct attribute *attr, const char *group)
 319 {
 320 }
 321
 322 static inline int sysfs_merge_group(struct kobject *kobj,
 323                        const struct attribute_group *grp)
 324 {
 325         return 0;
 326 }
 327
 328 static inline void sysfs_unmerge_group(struct kobject *kobj,
 329                        const struct attribute_group *grp)
 330 {
 331 }
 332
 333 static inline int sysfs_add_link_to_group(struct kobject *kobj,
 334                 const char *group_name, struct kobject *target,
 335                 const char *link_name)
 336 {
 337         return 0;
 338 }
 339
 340 static inline void sysfs_remove_link_from_group(struct kobject *kobj,
 341                 const char *group_name, const char *link_name)
 342 {
 343 }
 344
 345 static inline void sysfs_notify(struct kobject *kobj, const char *dir,
 346                                 const char *attr)
 347 {
 348 }
 349 static inline void sysfs_notify_dirent(struct sysfs_dirent *sd)
 350 {
 351 }
 352 static inline
 353 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
 354                                       const void *ns,
 355                                       const unsigned char *name)
 356 {
 357         return NULL;
 358 }
 359 static inline struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd)
 360 {
 361         return NULL;
 362 }
 363 static inline void sysfs_put(struct sysfs_dirent *sd)
 364 {
 365 }
 366
 367 static inline int __must_check sysfs_init(void)
 368 {
 369         return 0;
 370 }
 371
 372 #endif /* CONFIG_SYSFS */
 373
 374 #endif /* _SYSFS_H_ */