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 <[email protected]> 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 <linux/atomic.h> 29 #include <linux/workqueue.h> 30 31 #define UEVENT_HELPER_PATH_LEN 256 32 #define UEVENT_NUM_ENVP 32 /* number of env pointers */ 33 #define UEVENT_BUFFER_SIZE 2048 /* buffer for the variables */ 34 35 /* path to the userspace helper executed on an event */ 36 extern char uevent_helper[]; 37 38 /* counter to tag the uevent, read only except for the kobject core */ 39 extern u64 uevent_seqnum; 40 41 /* 42 * The actions here must match the index to the string array 43 * in lib/kobject_uevent.c 44 * 45 * Do not add new actions here without checking with the driver-core 46 * maintainers. Action strings are not meant to express subsystem 47 * or device specific properties. In most cases you want to send a 48 * kobject_uevent_env(kobj, KOBJ_CHANGE, env) with additional event 49 * specific variables added to the event environment. 50 */ 51 enum kobject_action { 52 KOBJ_ADD, 53 KOBJ_REMOVE, 54 KOBJ_CHANGE, 55 KOBJ_MOVE, 56 KOBJ_ONLINE, 57 KOBJ_OFFLINE, 58 KOBJ_MAX 59 }; 60 61 struct kobject { 62 const char *name; 63 struct list_head entry; 64 struct kobject *parent; 65 struct kset *kset; 66 struct kobj_type *ktype; 67 struct sysfs_dirent *sd; 68 struct kref kref; 69 #ifdef CONFIG_DEBUG_KOBJECT_RELEASE 70 struct delayed_work release; 71 #endif 72 unsigned int state_initialized:1; 73 unsigned int state_in_sysfs:1; 74 unsigned int state_add_uevent_sent:1; 75 unsigned int state_remove_uevent_sent:1; 76 unsigned int uevent_suppress:1; 77 }; 78 79 extern __printf(2, 3) 80 int kobject_set_name(struct kobject *kobj, const char *name, ...); 81 extern int kobject_set_name_vargs(struct kobject *kobj, const char *fmt, 82 va_list vargs); 83 84 static inline const char *kobject_name(const struct kobject *kobj) 85 { 86 return kobj->name; 87 } 88 89 extern void kobject_init(struct kobject *kobj, struct kobj_type *ktype); 90 extern __printf(3, 4) __must_check 91 int kobject_add(struct kobject *kobj, struct kobject *parent, 92 const char *fmt, ...); 93 extern __printf(4, 5) __must_check 94 int kobject_init_and_add(struct kobject *kobj, 95 struct kobj_type *ktype, struct kobject *parent, 96 const char *fmt, ...); 97 98 extern void kobject_del(struct kobject *kobj); 99 100 extern struct kobject * __must_check kobject_create(void); 101 extern struct kobject * __must_check kobject_create_and_add(const char *name, 102 struct kobject *parent); 103 104 extern int __must_check kobject_rename(struct kobject *, const char *new_name); 105 extern int __must_check kobject_move(struct kobject *, struct kobject *); 106 107 extern struct kobject *kobject_get(struct kobject *kobj); 108 extern void kobject_put(struct kobject *kobj); 109 110 extern const void *kobject_namespace(struct kobject *kobj); 111 extern char *kobject_get_path(struct kobject *kobj, gfp_t flag); 112 113 struct kobj_type { 114 void (*release)(struct kobject *kobj); 115 const struct sysfs_ops *sysfs_ops; 116 struct attribute **default_attrs; 117 const struct kobj_ns_type_operations *(*child_ns_type)(struct kobject *kobj); 118 const void *(*namespace)(struct kobject *kobj); 119 }; 120 121 struct kobj_uevent_env { 122 char *envp[UEVENT_NUM_ENVP]; 123 int envp_idx; 124 char buf[UEVENT_BUFFER_SIZE]; 125 int buflen; 126 }; 127 128 struct kset_uevent_ops { 129 int (* const filter)(struct kset *kset, struct kobject *kobj); 130 const char *(* const name)(struct kset *kset, struct kobject *kobj); 131 int (* const uevent)(struct kset *kset, struct kobject *kobj, 132 struct kobj_uevent_env *env); 133 }; 134 135 struct kobj_attribute { 136 struct attribute attr; 137 ssize_t (*show)(struct kobject *kobj, struct kobj_attribute *attr, 138 char *buf); 139 ssize_t (*store)(struct kobject *kobj, struct kobj_attribute *attr, 140 const char *buf, size_t count); 141 }; 142 143 extern const struct sysfs_ops kobj_sysfs_ops; 144 145 struct sock; 146 147 /** 148 * struct kset - a set of kobjects of a specific type, belonging to a specific subsystem. 149 * 150 * A kset defines a group of kobjects. They can be individually 151 * different "types" but overall these kobjects all want to be grouped 152 * together and operated on in the same manner. ksets are used to 153 * define the attribute callbacks and other common events that happen to 154 * a kobject. 155 * 156 * @list: the list of all kobjects for this kset 157 * @list_lock: a lock for iterating over the kobjects 158 * @kobj: the embedded kobject for this kset (recursion, isn't it fun...) 159 * @uevent_ops: the set of uevent operations for this kset. These are 160 * called whenever a kobject has something happen to it so that the kset 161 * can add new environment variables, or filter out the uevents if so 162 * desired. 163 */ 164 struct kset { 165 struct list_head list; 166 spinlock_t list_lock; 167 struct kobject kobj; 168 const struct kset_uevent_ops *uevent_ops; 169 }; 170 171 extern void kset_init(struct kset *kset); 172 extern int __must_check kset_register(struct kset *kset); 173 extern void kset_unregister(struct kset *kset); 174 extern struct kset * __must_check kset_create_and_add(const char *name, 175 const struct kset_uevent_ops *u, 176 struct kobject *parent_kobj); 177 178 static inline struct kset *to_kset(struct kobject *kobj) 179 { 180 return kobj ? container_of(kobj, struct kset, kobj) : NULL; 181 } 182 183 static inline struct kset *kset_get(struct kset *k) 184 { 185 return k ? to_kset(kobject_get(&k->kobj)) : NULL; 186 } 187 188 static inline void kset_put(struct kset *k) 189 { 190 kobject_put(&k->kobj); 191 } 192 193 static inline struct kobj_type *get_ktype(struct kobject *kobj) 194 { 195 return kobj->ktype; 196 } 197 198 extern struct kobject *kset_find_obj(struct kset *, const char *); 199 200 /* The global /sys/kernel/ kobject for people to chain off of */ 201 extern struct kobject *kernel_kobj; 202 /* The global /sys/kernel/mm/ kobject for people to chain off of */ 203 extern struct kobject *mm_kobj; 204 /* The global /sys/hypervisor/ kobject for people to chain off of */ 205 extern struct kobject *hypervisor_kobj; 206 /* The global /sys/power/ kobject for people to chain off of */ 207 extern struct kobject *power_kobj; 208 /* The global /sys/firmware/ kobject for people to chain off of */ 209 extern struct kobject *firmware_kobj; 210 211 int kobject_uevent(struct kobject *kobj, enum kobject_action action); 212 int kobject_uevent_env(struct kobject *kobj, enum kobject_action action, 213 char *envp[]); 214 215 __printf(2, 3) 216 int add_uevent_var(struct kobj_uevent_env *env, const char *format, ...); 217 218 int kobject_action_type(const char *buf, size_t count, 219 enum kobject_action *type); 220 221 #endif /* _KOBJECT_H_ */ 222