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 16#ifndef _KOBJECT_H_ 17#define _KOBJECT_H_ 18 19#include <linux/types.h> 20#include <linux/list.h> 21#include <linux/sysfs.h> 22#include <linux/compiler.h> 23#include <linux/spinlock.h> 24#include <linux/kref.h> 25#include <linux/kobject_ns.h> 26#include <linux/kernel.h> 27#include <linux/wait.h> 28#include <asm/atomic.h> 29 30#define UEVENT_HELPER_PATH_LEN 256 31#define UEVENT_NUM_ENVP 32 /* number of env pointers */ 32#define UEVENT_BUFFER_SIZE 2048 /* buffer for the variables */ 33 34/* path to the userspace helper executed on an event */ 35extern char uevent_helper[]; 36 37/* counter to tag the uevent, read only except for the kobject core */ 38extern u64 uevent_seqnum; 39 40/* 41 * The actions here must match the index to the string array 42 * in lib/kobject_uevent.c 43 * 44 * Do not add new actions here without checking with the driver-core 45 * maintainers. Action strings are not meant to express subsystem 46 * or device specific properties. In most cases you want to send a 47 * kobject_uevent_env(kobj, KOBJ_CHANGE, env) with additional event 48 * specific variables added to the event environment. 49 */ 50enum kobject_action { 51 KOBJ_ADD, 52 KOBJ_REMOVE, 53 KOBJ_CHANGE, 54 KOBJ_MOVE, 55 KOBJ_ONLINE, 56 KOBJ_OFFLINE, 57 KOBJ_MAX 58}; 59 60struct kobject { 61 const char *name; 62 struct list_head entry; 63 struct kobject *parent; 64 struct kset *kset; 65 struct kobj_type *ktype; 66 struct sysfs_dirent *sd; 67 struct kref kref; 68 unsigned int state_initialized:1; 69 unsigned int state_in_sysfs:1; 70 unsigned int state_add_uevent_sent:1; 71 unsigned int state_remove_uevent_sent:1; 72 unsigned int uevent_suppress:1; 73}; 74 75extern int kobject_set_name(struct kobject *kobj, const char *name, ...) 76 __attribute__((format(printf, 2, 3))); 77extern int kobject_set_name_vargs(struct kobject *kobj, const char *fmt, 78 va_list vargs); 79 80static inline const char *kobject_name(const struct kobject *kobj) 81{ 82 return kobj->name; 83} 84 85extern void kobject_init(struct kobject *kobj, struct kobj_type *ktype); 86extern int __must_check kobject_add(struct kobject *kobj, 87 struct kobject *parent, 88 const char *fmt, ...); 89extern int __must_check kobject_init_and_add(struct kobject *kobj, 90 struct kobj_type *ktype, 91 struct kobject *parent, 92 const char *fmt, ...); 93 94extern void kobject_del(struct kobject *kobj); 95 96extern struct kobject * __must_check kobject_create(void); 97extern struct kobject * __must_check kobject_create_and_add(const char *name, 98 struct kobject *parent); 99 100extern int __must_check kobject_rename(struct kobject *, const char *new_name); 101extern int __must_check kobject_move(struct kobject *, struct kobject *); 102 103extern struct kobject *kobject_get(struct kobject *kobj); 104extern void kobject_put(struct kobject *kobj); 105 106extern char *kobject_get_path(struct kobject *kobj, gfp_t flag); 107 108struct kobj_type { 109 void (*release)(struct kobject *kobj); 110 const struct sysfs_ops *sysfs_ops; 111 struct attribute **default_attrs; 112 const struct kobj_ns_type_operations *(*child_ns_type)(struct kobject *kobj); 113 const void *(*namespace)(struct kobject *kobj); 114}; 115 116struct kobj_uevent_env { 117 char *envp[UEVENT_NUM_ENVP]; 118 int envp_idx; 119 char buf[UEVENT_BUFFER_SIZE]; 120 int buflen; 121}; 122 123struct kset_uevent_ops { 124 int (* const filter)(struct kset *kset, struct kobject *kobj); 125 const char *(* const name)(struct kset *kset, struct kobject *kobj); 126 int (* const uevent)(struct kset *kset, struct kobject *kobj, 127 struct kobj_uevent_env *env); 128}; 129 130struct kobj_attribute { 131 struct attribute attr; 132 ssize_t (*show)(struct kobject *kobj, struct kobj_attribute *attr, 133 char *buf); 134 ssize_t (*store)(struct kobject *kobj, struct kobj_attribute *attr, 135 const char *buf, size_t count); 136}; 137 138extern const struct sysfs_ops kobj_sysfs_ops; 139 140struct sock; 141 142/** 143 * struct kset - a set of kobjects of a specific type, belonging to a specific subsystem. 144 * 145 * A kset defines a group of kobjects. They can be individually 146 * different "types" but overall these kobjects all want to be grouped 147 * together and operated on in the same manner. ksets are used to 148 * define the attribute callbacks and other common events that happen to 149 * a kobject. 150 * 151 * @list: the list of all kobjects for this kset 152 * @list_lock: a lock for iterating over the kobjects 153 * @kobj: the embedded kobject for this kset (recursion, isn't it fun...) 154 * @uevent_ops: the set of uevent operations for this kset. These are 155 * called whenever a kobject has something happen to it so that the kset 156 * can add new environment variables, or filter out the uevents if so 157 * desired. 158 */ 159struct kset { 160 struct list_head list; 161 spinlock_t list_lock; 162 struct kobject kobj; 163 const struct kset_uevent_ops *uevent_ops; 164}; 165 166extern void kset_init(struct kset *kset); 167extern int __must_check kset_register(struct kset *kset); 168extern void kset_unregister(struct kset *kset); 169extern struct kset * __must_check kset_create_and_add(const char *name, 170 const struct kset_uevent_ops *u, 171 struct kobject *parent_kobj); 172 173static inline struct kset *to_kset(struct kobject *kobj) 174{ 175 return kobj ? container_of(kobj, struct kset, kobj) : NULL; 176} 177 178static inline struct kset *kset_get(struct kset *k) 179{ 180 return k ? to_kset(kobject_get(&k->kobj)) : NULL; 181} 182 183static inline void kset_put(struct kset *k) 184{ 185 kobject_put(&k->kobj); 186} 187 188static inline struct kobj_type *get_ktype(struct kobject *kobj) 189{ 190 return kobj->ktype; 191} 192 193extern struct kobject *kset_find_obj(struct kset *, const char *); 194 195/* The global /sys/kernel/ kobject for people to chain off of */ 196extern struct kobject *kernel_kobj; 197/* The global /sys/kernel/mm/ kobject for people to chain off of */ 198extern struct kobject *mm_kobj; 199/* The global /sys/hypervisor/ kobject for people to chain off of */ 200extern struct kobject *hypervisor_kobj; 201/* The global /sys/power/ kobject for people to chain off of */ 202extern struct kobject *power_kobj; 203/* The global /sys/firmware/ kobject for people to chain off of */ 204extern struct kobject *firmware_kobj; 205 206#if defined(CONFIG_HOTPLUG) 207int kobject_uevent(struct kobject *kobj, enum kobject_action action); 208int kobject_uevent_env(struct kobject *kobj, enum kobject_action action, 209 char *envp[]); 210 211int add_uevent_var(struct kobj_uevent_env *env, const char *format, ...) 212 __attribute__((format (printf, 2, 3))); 213 214int kobject_action_type(const char *buf, size_t count, 215 enum kobject_action *type); 216#else 217static inline int kobject_uevent(struct kobject *kobj, 218 enum kobject_action action) 219{ return 0; } 220static inline int kobject_uevent_env(struct kobject *kobj, 221 enum kobject_action action, 222 char *envp[]) 223{ return 0; } 224 225static inline int add_uevent_var(struct kobj_uevent_env *env, 226 const char *format, ...) 227{ return 0; } 228 229static inline int kobject_action_type(const char *buf, size_t count, 230 enum kobject_action *type) 231{ return -EINVAL; } 232#endif 233 234#endif /* _KOBJECT_H_ */ 235