kobject.h 6.7 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225
  1. /*
  2. * kobject.h - generic kernel object infrastructure.
  3. *
  4. * Copyright (c) 2002-2003 Patrick Mochel
  5. * Copyright (c) 2002-2003 Open Source Development Labs
  6. * Copyright (c) 2006-2008 Greg Kroah-Hartman <greg@kroah.com>
  7. * Copyright (c) 2006-2008 Novell Inc.
  8. *
  9. * This file is released under the GPLv2.
  10. *
  11. * Please read Documentation/kobject.txt before using the kobject
  12. * interface, ESPECIALLY the parts about reference counts and object
  13. * destructors.
  14. */
  15. #ifndef _KOBJECT_H_
  16. #define _KOBJECT_H_
  17. #include <linux/types.h>
  18. #include <linux/list.h>
  19. #include <linux/sysfs.h>
  20. #include <linux/compiler.h>
  21. #include <linux/spinlock.h>
  22. #include <linux/kref.h>
  23. #include <linux/kernel.h>
  24. #include <linux/wait.h>
  25. #include <asm/atomic.h>
  26. #define KOBJ_NAME_LEN 20
  27. #define UEVENT_HELPER_PATH_LEN 256
  28. #define UEVENT_NUM_ENVP 32 /* number of env pointers */
  29. #define UEVENT_BUFFER_SIZE 2048 /* buffer for the variables */
  30. /* path to the userspace helper executed on an event */
  31. extern char uevent_helper[];
  32. /* counter to tag the uevent, read only except for the kobject core */
  33. extern u64 uevent_seqnum;
  34. /*
  35. * The actions here must match the index to the string array
  36. * in lib/kobject_uevent.c
  37. *
  38. * Do not add new actions here without checking with the driver-core
  39. * maintainers. Action strings are not meant to express subsystem
  40. * or device specific properties. In most cases you want to send a
  41. * kobject_uevent_env(kobj, KOBJ_CHANGE, env) with additional event
  42. * specific variables added to the event environment.
  43. */
  44. enum kobject_action {
  45. KOBJ_ADD,
  46. KOBJ_REMOVE,
  47. KOBJ_CHANGE,
  48. KOBJ_MOVE,
  49. KOBJ_ONLINE,
  50. KOBJ_OFFLINE,
  51. KOBJ_MAX
  52. };
  53. struct kobject {
  54. const char *name;
  55. struct kref kref;
  56. struct list_head entry;
  57. struct kobject *parent;
  58. struct kset *kset;
  59. struct kobj_type *ktype;
  60. struct sysfs_dirent *sd;
  61. unsigned int state_initialized:1;
  62. unsigned int state_in_sysfs:1;
  63. unsigned int state_add_uevent_sent:1;
  64. unsigned int state_remove_uevent_sent:1;
  65. };
  66. extern int kobject_set_name(struct kobject *kobj, const char *name, ...)
  67. __attribute__((format(printf, 2, 3)));
  68. static inline const char *kobject_name(const struct kobject *kobj)
  69. {
  70. return kobj->name;
  71. }
  72. extern void kobject_init(struct kobject *kobj, struct kobj_type *ktype);
  73. extern int __must_check kobject_add(struct kobject *kobj,
  74. struct kobject *parent,
  75. const char *fmt, ...);
  76. extern int __must_check kobject_init_and_add(struct kobject *kobj,
  77. struct kobj_type *ktype,
  78. struct kobject *parent,
  79. const char *fmt, ...);
  80. extern void kobject_del(struct kobject *kobj);
  81. extern struct kobject * __must_check kobject_create(void);
  82. extern struct kobject * __must_check kobject_create_and_add(const char *name,
  83. struct kobject *parent);
  84. extern int __must_check kobject_rename(struct kobject *, const char *new_name);
  85. extern int __must_check kobject_move(struct kobject *, struct kobject *);
  86. extern struct kobject *kobject_get(struct kobject *kobj);
  87. extern void kobject_put(struct kobject *kobj);
  88. extern char *kobject_get_path(struct kobject *kobj, gfp_t flag);
  89. struct kobj_type {
  90. void (*release)(struct kobject *kobj);
  91. struct sysfs_ops *sysfs_ops;
  92. struct attribute **default_attrs;
  93. };
  94. struct kobj_uevent_env {
  95. char *envp[UEVENT_NUM_ENVP];
  96. int envp_idx;
  97. char buf[UEVENT_BUFFER_SIZE];
  98. int buflen;
  99. };
  100. struct kset_uevent_ops {
  101. int (*filter)(struct kset *kset, struct kobject *kobj);
  102. const char *(*name)(struct kset *kset, struct kobject *kobj);
  103. int (*uevent)(struct kset *kset, struct kobject *kobj,
  104. struct kobj_uevent_env *env);
  105. };
  106. struct kobj_attribute {
  107. struct attribute attr;
  108. ssize_t (*show)(struct kobject *kobj, struct kobj_attribute *attr,
  109. char *buf);
  110. ssize_t (*store)(struct kobject *kobj, struct kobj_attribute *attr,
  111. const char *buf, size_t count);
  112. };
  113. extern struct sysfs_ops kobj_sysfs_ops;
  114. /**
  115. * struct kset - a set of kobjects of a specific type, belonging to a specific subsystem.
  116. *
  117. * A kset defines a group of kobjects. They can be individually
  118. * different "types" but overall these kobjects all want to be grouped
  119. * together and operated on in the same manner. ksets are used to
  120. * define the attribute callbacks and other common events that happen to
  121. * a kobject.
  122. *
  123. * @list: the list of all kobjects for this kset
  124. * @list_lock: a lock for iterating over the kobjects
  125. * @kobj: the embedded kobject for this kset (recursion, isn't it fun...)
  126. * @uevent_ops: the set of uevent operations for this kset. These are
  127. * called whenever a kobject has something happen to it so that the kset
  128. * can add new environment variables, or filter out the uevents if so
  129. * desired.
  130. */
  131. struct kset {
  132. struct list_head list;
  133. spinlock_t list_lock;
  134. struct kobject kobj;
  135. struct kset_uevent_ops *uevent_ops;
  136. };
  137. extern void kset_init(struct kset *kset);
  138. extern int __must_check kset_register(struct kset *kset);
  139. extern void kset_unregister(struct kset *kset);
  140. extern struct kset * __must_check kset_create_and_add(const char *name,
  141. struct kset_uevent_ops *u,
  142. struct kobject *parent_kobj);
  143. static inline struct kset *to_kset(struct kobject *kobj)
  144. {
  145. return kobj ? container_of(kobj, struct kset, kobj) : NULL;
  146. }
  147. static inline struct kset *kset_get(struct kset *k)
  148. {
  149. return k ? to_kset(kobject_get(&k->kobj)) : NULL;
  150. }
  151. static inline void kset_put(struct kset *k)
  152. {
  153. kobject_put(&k->kobj);
  154. }
  155. static inline struct kobj_type *get_ktype(struct kobject *kobj)
  156. {
  157. return kobj->ktype;
  158. }
  159. extern struct kobject *kset_find_obj(struct kset *, const char *);
  160. /* The global /sys/kernel/ kobject for people to chain off of */
  161. extern struct kobject *kernel_kobj;
  162. /* The global /sys/hypervisor/ kobject for people to chain off of */
  163. extern struct kobject *hypervisor_kobj;
  164. /* The global /sys/power/ kobject for people to chain off of */
  165. extern struct kobject *power_kobj;
  166. /* The global /sys/firmware/ kobject for people to chain off of */
  167. extern struct kobject *firmware_kobj;
  168. #if defined(CONFIG_HOTPLUG)
  169. int kobject_uevent(struct kobject *kobj, enum kobject_action action);
  170. int kobject_uevent_env(struct kobject *kobj, enum kobject_action action,
  171. char *envp[]);
  172. int add_uevent_var(struct kobj_uevent_env *env, const char *format, ...)
  173. __attribute__((format (printf, 2, 3)));
  174. int kobject_action_type(const char *buf, size_t count,
  175. enum kobject_action *type);
  176. #else
  177. static inline int kobject_uevent(struct kobject *kobj,
  178. enum kobject_action action)
  179. { return 0; }
  180. static inline int kobject_uevent_env(struct kobject *kobj,
  181. enum kobject_action action,
  182. char *envp[])
  183. { return 0; }
  184. static inline int add_uevent_var(struct kobj_uevent_env *env,
  185. const char *format, ...)
  186. { return 0; }
  187. static inline int kobject_action_type(const char *buf, size_t count,
  188. enum kobject_action *type)
  189. { return -EINVAL; }
  190. #endif
  191. #endif /* _KOBJECT_H_ */