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
  24 /* FIXME
  25  * The *owner field is no longer used.
  26  * x86 tree has been cleaned up. The owner
  27  * attribute is still left for other arches.
  28  */
  29 struct attribute {
  30         const char              *name;
  31         struct module           *owner;
  32         mode_t                  mode;
  33 #ifdef CONFIG_DEBUG_LOCK_ALLOC
  34         struct lock_class_key   *key;
  35         struct lock_class_key   skey;
  36 #endif
  37 };
  38
  39 /**
  40  *      sysfs_attr_init - initialize a dynamically allocated sysfs attribute
  41  *      @attr: struct attribute to initialize
  42  *
  43  *      Initialize a dynamically allocated struct attribute so we can
  44  *      make lockdep happy.  This is a new requirement for attributes
  45  *      and initially this is only needed when lockdep is enabled.
  46  *      Lockdep gives a nice error when your attribute is added to
  47  *      sysfs if you don't have this.
  48  */
  49 #ifdef CONFIG_DEBUG_LOCK_ALLOC
  50 #define sysfs_attr_init(attr)                           \
  51 do {                                                    \
  52         static struct lock_class_key __key;             \
  53                                                         \
  54         (attr)->key = &__key;                           \
  55 } while(0)
  56 #else
  57 #define sysfs_attr_init(attr) do {} while(0)
  58 #endif
  59
  60 struct attribute_group {
  61         const char              *name;
  62         mode_t                  (*is_visible)(struct kobject *,
  63                                               struct attribute *, int);
  64         struct attribute        **attrs;
  65 };
  66
  67
  68
  69 /**
  70  * Use these macros to make defining attributes easier. See include/linux/device.h
  71  * for examples..
  72  */
  73
  74 #define __ATTR(_name,_mode,_show,_store) { \
  75         .attr = {.name = __stringify(_name), .mode = _mode },   \
  76         .show   = _show,                                        \
  77         .store  = _store,                                       \
  78 }
  79
  80 #define __ATTR_RO(_name) { \
  81         .attr   = { .name = __stringify(_name), .mode = 0444 }, \
  82         .show   = _name##_show,                                 \
  83 }
  84
  85 #define __ATTR_NULL { .attr = { .name = NULL } }
  86
  87 #define attr_name(_attr) (_attr).attr.name
  88
  89 struct vm_area_struct;
  90
  91 struct bin_attribute {
  92         struct attribute        attr;
  93         size_t                  size;
  94         void                    *private;
  95         ssize_t (*read)(struct kobject *, struct bin_attribute *,
  96                         char *, loff_t, size_t);
  97         ssize_t (*write)(struct kobject *, struct bin_attribute *,
  98                          char *, loff_t, size_t);
  99         int (*mmap)(struct kobject *, struct bin_attribute *attr,
 100                     struct vm_area_struct *vma);
 101 };
 102
 103 /**
 104  *      sysfs_bin_attr_init - initialize a dynamically allocated bin_attribute
 105  *      @attr: struct bin_attribute to initialize
 106  *
 107  *      Initialize a dynamically allocated struct bin_attribute so we
 108  *      can make lockdep happy.  This is a new requirement for
 109  *      attributes and initially this is only needed when lockdep is
 110  *      enabled.  Lockdep gives a nice error when your attribute is
 111  *      added to sysfs if you don't have this.
 112  */
 113 #define sysfs_bin_attr_init(bin_attr) sysfs_attr_init(&(bin_attr)->attr)
 114
 115 struct sysfs_ops {
 116         ssize_t (*show)(struct kobject *, struct attribute *,char *);
 117         ssize_t (*store)(struct kobject *,struct attribute *,const char *, size_t);
 118 };
 119
 120 struct sysfs_dirent;
 121
 122 #ifdef CONFIG_SYSFS
 123
 124 int sysfs_schedule_callback(struct kobject *kobj, void (*func)(void *),
 125                             void *data, struct module *owner);
 126
 127 int __must_check sysfs_create_dir(struct kobject *kobj);
 128 void sysfs_remove_dir(struct kobject *kobj);
 129 int __must_check sysfs_rename_dir(struct kobject *kobj, const char *new_name);
 130 int __must_check sysfs_move_dir(struct kobject *kobj,
 131                                 struct kobject *new_parent_kobj);
 132
 133 int __must_check sysfs_create_file(struct kobject *kobj,
 134                                    const struct attribute *attr);
 135 int __must_check sysfs_create_files(struct kobject *kobj,
 136                                    const struct attribute **attr);
 137 int __must_check sysfs_chmod_file(struct kobject *kobj, struct attribute *attr,
 138                                   mode_t mode);
 139 void sysfs_remove_file(struct kobject *kobj, const struct attribute *attr);
 140 void sysfs_remove_files(struct kobject *kobj, const struct attribute **attr);
 141
 142 int __must_check sysfs_create_bin_file(struct kobject *kobj,
 143                                        const struct bin_attribute *attr);
 144 void sysfs_remove_bin_file(struct kobject *kobj,
 145                            const struct bin_attribute *attr);
 146
 147 int __must_check sysfs_create_link(struct kobject *kobj, struct kobject *target,
 148                                    const char *name);
 149 int __must_check sysfs_create_link_nowarn(struct kobject *kobj,
 150                                           struct kobject *target,
 151                                           const char *name);
 152 void sysfs_remove_link(struct kobject *kobj, const char *name);
 153
 154 int sysfs_rename_link(struct kobject *kobj, struct kobject *target,
 155                         const char *old_name, const char *new_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
 168 void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr);
 169 void sysfs_notify_dirent(struct sysfs_dirent *sd);
 170 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
 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 int __must_check sysfs_init(void);
 176
 177 #else /* CONFIG_SYSFS */
 178
 179 static inline int sysfs_schedule_callback(struct kobject *kobj,
 180                 void (*func)(void *), void *data, struct module *owner)
 181 {
 182         return -ENOSYS;
 183 }
 184
 185 static inline int sysfs_create_dir(struct kobject *kobj)
 186 {
 187         return 0;
 188 }
 189
 190 static inline void sysfs_remove_dir(struct kobject *kobj)
 191 {
 192 }
 193
 194 static inline int sysfs_rename_dir(struct kobject *kobj, const char *new_name)
 195 {
 196         return 0;
 197 }
 198
 199 static inline int sysfs_move_dir(struct kobject *kobj,
 200                                  struct kobject *new_parent_kobj)
 201 {
 202         return 0;
 203 }
 204
 205 static inline int sysfs_create_file(struct kobject *kobj,
 206                                     const struct attribute *attr)
 207 {
 208         return 0;
 209 }
 210
 211 static inline int sysfs_create_files(struct kobject *kobj,
 212                                     const struct attribute **attr)
 213 {
 214         return 0;
 215 }
 216
 217 static inline int sysfs_chmod_file(struct kobject *kobj,
 218                                    struct attribute *attr, mode_t mode)
 219 {
 220         return 0;
 221 }
 222
 223 static inline void sysfs_remove_file(struct kobject *kobj,
 224                                      const struct attribute *attr)
 225 {
 226 }
 227
 228 static inline void sysfs_remove_files(struct kobject *kobj,
 229                                      const struct attribute **attr)
 230 {
 231 }
 232
 233 static inline int sysfs_create_bin_file(struct kobject *kobj,
 234                                         const struct bin_attribute *attr)
 235 {
 236         return 0;
 237 }
 238
 239 static inline void sysfs_remove_bin_file(struct kobject *kobj,
 240                                          const struct bin_attribute *attr)
 241 {
 242 }
 243
 244 static inline int sysfs_create_link(struct kobject *kobj,
 245                                     struct kobject *target, const char *name)
 246 {
 247         return 0;
 248 }
 249
 250 static inline int sysfs_create_link_nowarn(struct kobject *kobj,
 251                                            struct kobject *target,
 252                                            const char *name)
 253 {
 254         return 0;
 255 }
 256
 257 static inline void sysfs_remove_link(struct kobject *kobj, const char *name)
 258 {
 259 }
 260
 261 static inline int sysfs_rename_link(struct kobject *k, struct kobject *t,
 262                                     const char *old_name, const char *new_name)
 263 {
 264         return 0;
 265 }
 266
 267 static inline int sysfs_create_group(struct kobject *kobj,
 268                                      const struct attribute_group *grp)
 269 {
 270         return 0;
 271 }
 272
 273 static inline int sysfs_update_group(struct kobject *kobj,
 274                                 const struct attribute_group *grp)
 275 {
 276         return 0;
 277 }
 278
 279 static inline void sysfs_remove_group(struct kobject *kobj,
 280                                       const struct attribute_group *grp)
 281 {
 282 }
 283
 284 static inline int sysfs_add_file_to_group(struct kobject *kobj,
 285                 const struct attribute *attr, const char *group)
 286 {
 287         return 0;
 288 }
 289
 290 static inline void sysfs_remove_file_from_group(struct kobject *kobj,
 291                 const struct attribute *attr, const char *group)
 292 {
 293 }
 294
 295 static inline void sysfs_notify(struct kobject *kobj, const char *dir,
 296                                 const char *attr)
 297 {
 298 }
 299 static inline void sysfs_notify_dirent(struct sysfs_dirent *sd)
 300 {
 301 }
 302 static inline
 303 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
 304                                       const unsigned char *name)
 305 {
 306         return NULL;
 307 }
 308 static inline struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd)
 309 {
 310         return NULL;
 311 }
 312 static inline void sysfs_put(struct sysfs_dirent *sd)
 313 {
 314 }
 315
 316 static inline int __must_check sysfs_init(void)
 317 {
 318         return 0;
 319 }
 320
 321 static inline void sysfs_printk_last_file(void)
 322 {
 323 }
 324
 325 #endif /* CONFIG_SYSFS */
 326
 327 #endif /* _SYSFS_H_ */