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 void sysfs_printk_last_file(void);
 180
 181 /* Called to clear a ns tag when it is no longer valid */
 182 void sysfs_exit_ns(enum kobj_ns_type type, const void *tag);
 183
 184 int __must_check sysfs_init(void);
 185
 186 #else /* CONFIG_SYSFS */
 187
 188 static inline int sysfs_schedule_callback(struct kobject *kobj,
 189                 void (*func)(void *), void *data, struct module *owner)
 190 {
 191         return -ENOSYS;
 192 }
 193
 194 static inline int sysfs_create_dir(struct kobject *kobj)
 195 {
 196         return 0;
 197 }
 198
 199 static inline void sysfs_remove_dir(struct kobject *kobj)
 200 {
 201 }
 202
 203 static inline int sysfs_rename_dir(struct kobject *kobj, const char *new_name)
 204 {
 205         return 0;
 206 }
 207
 208 static inline int sysfs_move_dir(struct kobject *kobj,
 209                                  struct kobject *new_parent_kobj)
 210 {
 211         return 0;
 212 }
 213
 214 static inline int sysfs_create_file(struct kobject *kobj,
 215                                     const struct attribute *attr)
 216 {
 217         return 0;
 218 }
 219
 220 static inline int sysfs_create_files(struct kobject *kobj,
 221                                     const struct attribute **attr)
 222 {
 223         return 0;
 224 }
 225
 226 static inline int sysfs_chmod_file(struct kobject *kobj,
 227                                    const struct attribute *attr, mode_t mode)
 228 {
 229         return 0;
 230 }
 231
 232 static inline void sysfs_remove_file(struct kobject *kobj,
 233                                      const struct attribute *attr)
 234 {
 235 }
 236
 237 static inline void sysfs_remove_files(struct kobject *kobj,
 238                                      const struct attribute **attr)
 239 {
 240 }
 241
 242 static inline int sysfs_create_bin_file(struct kobject *kobj,
 243                                         const struct bin_attribute *attr)
 244 {
 245         return 0;
 246 }
 247
 248 static inline void sysfs_remove_bin_file(struct kobject *kobj,
 249                                          const struct bin_attribute *attr)
 250 {
 251 }
 252
 253 static inline int sysfs_create_link(struct kobject *kobj,
 254                                     struct kobject *target, const char *name)
 255 {
 256         return 0;
 257 }
 258
 259 static inline int sysfs_create_link_nowarn(struct kobject *kobj,
 260                                            struct kobject *target,
 261                                            const char *name)
 262 {
 263         return 0;
 264 }
 265
 266 static inline void sysfs_remove_link(struct kobject *kobj, const char *name)
 267 {
 268 }
 269
 270 static inline int sysfs_rename_link(struct kobject *k, struct kobject *t,
 271                                     const char *old_name, const char *new_name)
 272 {
 273         return 0;
 274 }
 275
 276 static inline void sysfs_delete_link(struct kobject *k, struct kobject *t,
 277                                      const char *name)
 278 {
 279 }
 280
 281 static inline int sysfs_create_group(struct kobject *kobj,
 282                                      const struct attribute_group *grp)
 283 {
 284         return 0;
 285 }
 286
 287 static inline int sysfs_update_group(struct kobject *kobj,
 288                                 const struct attribute_group *grp)
 289 {
 290         return 0;
 291 }
 292
 293 static inline void sysfs_remove_group(struct kobject *kobj,
 294                                       const struct attribute_group *grp)
 295 {
 296 }
 297
 298 static inline int sysfs_add_file_to_group(struct kobject *kobj,
 299                 const struct attribute *attr, const char *group)
 300 {
 301         return 0;
 302 }
 303
 304 static inline void sysfs_remove_file_from_group(struct kobject *kobj,
 305                 const struct attribute *attr, const char *group)
 306 {
 307 }
 308
 309 static inline int sysfs_merge_group(struct kobject *kobj,
 310                        const struct attribute_group *grp)
 311 {
 312         return 0;
 313 }
 314
 315 static inline void sysfs_unmerge_group(struct kobject *kobj,
 316                        const struct attribute_group *grp)
 317 {
 318 }
 319
 320 static inline void sysfs_notify(struct kobject *kobj, const char *dir,
 321                                 const char *attr)
 322 {
 323 }
 324 static inline void sysfs_notify_dirent(struct sysfs_dirent *sd)
 325 {
 326 }
 327 static inline
 328 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
 329                                       const void *ns,
 330                                       const unsigned char *name)
 331 {
 332         return NULL;
 333 }
 334 static inline struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd)
 335 {
 336         return NULL;
 337 }
 338 static inline void sysfs_put(struct sysfs_dirent *sd)
 339 {
 340 }
 341
 342 static inline void sysfs_exit_ns(int type, const void *tag)
 343 {
 344 }
 345
 346 static inline int __must_check sysfs_init(void)
 347 {
 348         return 0;
 349 }
 350
 351 static inline void sysfs_printk_last_file(void)
 352 {
 353 }
 354
 355 #endif /* CONFIG_SYSFS */
 356
 357 #endif /* _SYSFS_H_ */