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