kobject.h 7.3 KB

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  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/kobject_ns.h>
  24. #include <linux/kernel.h>
  25. #include <linux/wait.h>
  26. #include <asm/atomic.h>
  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 list_head entry;
  56. struct kobject *parent;
  57. struct kset *kset;
  58. struct kobj_type *ktype;
  59. struct sysfs_dirent *sd;
  60. struct kref kref;
  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. unsigned int uevent_suppress:1;
  66. };
  67. extern int kobject_set_name(struct kobject *kobj, const char *name, ...)
  68. __attribute__((format(printf, 2, 3)));
  69. extern int kobject_set_name_vargs(struct kobject *kobj, const char *fmt,
  70. va_list vargs);
  71. static inline const char *kobject_name(const struct kobject *kobj)
  72. {
  73. return kobj->name;
  74. }
  75. extern void kobject_init(struct kobject *kobj, struct kobj_type *ktype);
  76. extern int __must_check kobject_add(struct kobject *kobj,
  77. struct kobject *parent,
  78. const char *fmt, ...)
  79. __attribute__((format(printf, 3, 4)));
  80. extern int __must_check kobject_init_and_add(struct kobject *kobj,
  81. struct kobj_type *ktype,
  82. struct kobject *parent,
  83. const char *fmt, ...)
  84. __attribute__((format(printf, 4, 5)));
  85. extern void kobject_del(struct kobject *kobj);
  86. extern struct kobject * __must_check kobject_create(void);
  87. extern struct kobject * __must_check kobject_create_and_add(const char *name,
  88. struct kobject *parent);
  89. extern int __must_check kobject_rename(struct kobject *, const char *new_name);
  90. extern int __must_check kobject_move(struct kobject *, struct kobject *);
  91. extern struct kobject *kobject_get(struct kobject *kobj);
  92. extern void kobject_put(struct kobject *kobj);
  93. extern char *kobject_get_path(struct kobject *kobj, gfp_t flag);
  94. struct kobj_type {
  95. void (*release)(struct kobject *kobj);
  96. const struct sysfs_ops *sysfs_ops;
  97. struct attribute **default_attrs;
  98. const struct kobj_ns_type_operations *(*child_ns_type)(struct kobject *kobj);
  99. const void *(*namespace)(struct kobject *kobj);
  100. };
  101. struct kobj_uevent_env {
  102. char *envp[UEVENT_NUM_ENVP];
  103. int envp_idx;
  104. char buf[UEVENT_BUFFER_SIZE];
  105. int buflen;
  106. };
  107. struct kset_uevent_ops {
  108. int (* const filter)(struct kset *kset, struct kobject *kobj);
  109. const char *(* const name)(struct kset *kset, struct kobject *kobj);
  110. int (* const uevent)(struct kset *kset, struct kobject *kobj,
  111. struct kobj_uevent_env *env);
  112. };
  113. struct kobj_attribute {
  114. struct attribute attr;
  115. ssize_t (*show)(struct kobject *kobj, struct kobj_attribute *attr,
  116. char *buf);
  117. ssize_t (*store)(struct kobject *kobj, struct kobj_attribute *attr,
  118. const char *buf, size_t count);
  119. };
  120. extern const struct sysfs_ops kobj_sysfs_ops;
  121. struct sock;
  122. /**
  123. * struct kset - a set of kobjects of a specific type, belonging to a specific subsystem.
  124. *
  125. * A kset defines a group of kobjects. They can be individually
  126. * different "types" but overall these kobjects all want to be grouped
  127. * together and operated on in the same manner. ksets are used to
  128. * define the attribute callbacks and other common events that happen to
  129. * a kobject.
  130. *
  131. * @list: the list of all kobjects for this kset
  132. * @list_lock: a lock for iterating over the kobjects
  133. * @kobj: the embedded kobject for this kset (recursion, isn't it fun...)
  134. * @uevent_ops: the set of uevent operations for this kset. These are
  135. * called whenever a kobject has something happen to it so that the kset
  136. * can add new environment variables, or filter out the uevents if so
  137. * desired.
  138. */
  139. struct kset {
  140. struct list_head list;
  141. spinlock_t list_lock;
  142. struct kobject kobj;
  143. const struct kset_uevent_ops *uevent_ops;
  144. };
  145. extern void kset_init(struct kset *kset);
  146. extern int __must_check kset_register(struct kset *kset);
  147. extern void kset_unregister(struct kset *kset);
  148. extern struct kset * __must_check kset_create_and_add(const char *name,
  149. const struct kset_uevent_ops *u,
  150. struct kobject *parent_kobj);
  151. static inline struct kset *to_kset(struct kobject *kobj)
  152. {
  153. return kobj ? container_of(kobj, struct kset, kobj) : NULL;
  154. }
  155. static inline struct kset *kset_get(struct kset *k)
  156. {
  157. return k ? to_kset(kobject_get(&k->kobj)) : NULL;
  158. }
  159. static inline void kset_put(struct kset *k)
  160. {
  161. kobject_put(&k->kobj);
  162. }
  163. static inline struct kobj_type *get_ktype(struct kobject *kobj)
  164. {
  165. return kobj->ktype;
  166. }
  167. extern struct kobject *kset_find_obj(struct kset *, const char *);
  168. extern struct kobject *kset_find_obj_hinted(struct kset *, const char *,
  169. struct kobject *);
  170. /* The global /sys/kernel/ kobject for people to chain off of */
  171. extern struct kobject *kernel_kobj;
  172. /* The global /sys/kernel/mm/ kobject for people to chain off of */
  173. extern struct kobject *mm_kobj;
  174. /* The global /sys/hypervisor/ kobject for people to chain off of */
  175. extern struct kobject *hypervisor_kobj;
  176. /* The global /sys/power/ kobject for people to chain off of */
  177. extern struct kobject *power_kobj;
  178. /* The global /sys/firmware/ kobject for people to chain off of */
  179. extern struct kobject *firmware_kobj;
  180. #if defined(CONFIG_HOTPLUG)
  181. int kobject_uevent(struct kobject *kobj, enum kobject_action action);
  182. int kobject_uevent_env(struct kobject *kobj, enum kobject_action action,
  183. char *envp[]);
  184. int add_uevent_var(struct kobj_uevent_env *env, const char *format, ...)
  185. __attribute__((format (printf, 2, 3)));
  186. int kobject_action_type(const char *buf, size_t count,
  187. enum kobject_action *type);
  188. #else
  189. static inline int kobject_uevent(struct kobject *kobj,
  190. enum kobject_action action)
  191. { return 0; }
  192. static inline int kobject_uevent_env(struct kobject *kobj,
  193. enum kobject_action action,
  194. char *envp[])
  195. { return 0; }
  196. static inline __attribute__((format(printf, 2, 3)))
  197. int add_uevent_var(struct kobj_uevent_env *env, const char *format, ...)
  198. { return 0; }
  199. static inline int kobject_action_type(const char *buf, size_t count,
  200. enum kobject_action *type)
  201. { return -EINVAL; }
  202. #endif
  203. #endif /* _KOBJECT_H_ */