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 <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 #ifdef CONFIG_UEVENT_HELPER 36 /* path to the userspace helper executed on an event */ 37 extern char uevent_helper[]; 38 #endif 39 40 /* counter to tag the uevent, read only except for the kobject core */ 41 extern u64 uevent_seqnum; 42 43 /* 44 * The actions here must match the index to the string array 45 * in lib/kobject_uevent.c 46 * 47 * Do not add new actions here without checking with the driver-core 48 * maintainers. Action strings are not meant to express subsystem 49 * or device specific properties. In most cases you want to send a 50 * kobject_uevent_env(kobj, KOBJ_CHANGE, env) with additional event 51 * specific variables added to the event environment. 52 */ 53 enum kobject_action { 54 KOBJ_ADD, 55 KOBJ_REMOVE, 56 KOBJ_CHANGE, 57 KOBJ_MOVE, 58 KOBJ_ONLINE, 59 KOBJ_OFFLINE, 60 KOBJ_MAX 61 }; 62 63 struct kobject { 64 const char *name; 65 struct list_head entry; 66 struct kobject *parent; 67 struct kset *kset; 68 struct kobj_type *ktype; 69 struct kernfs_node *sd; 70 struct kref kref; 71 #ifdef CONFIG_DEBUG_KOBJECT_RELEASE 72 struct delayed_work release; 73 #endif 74 unsigned int state_initialized:1; 75 unsigned int state_in_sysfs:1; 76 unsigned int state_add_uevent_sent:1; 77 unsigned int state_remove_uevent_sent:1; 78 unsigned int uevent_suppress:1; 79 }; 80 81 extern __printf(2, 3) 82 int kobject_set_name(struct kobject *kobj, const char *name, ...); 83 extern __printf(2, 0) 84 int kobject_set_name_vargs(struct kobject *kobj, const char *fmt, 85 va_list vargs); 86 87 static inline const char *kobject_name(const struct kobject *kobj) 88 { 89 return kobj->name; 90 } 91 92 extern void kobject_init(struct kobject *kobj, struct kobj_type *ktype); 93 extern __printf(3, 4) __must_check 94 int kobject_add(struct kobject *kobj, struct kobject *parent, 95 const char *fmt, ...); 96 extern __printf(4, 5) __must_check 97 int kobject_init_and_add(struct kobject *kobj, 98 struct kobj_type *ktype, struct kobject *parent, 99 const char *fmt, ...); 100 101 extern void kobject_del(struct kobject *kobj); 102 103 extern struct kobject * __must_check kobject_create(void); 104 extern struct kobject * __must_check kobject_create_and_add(const char *name, 105 struct kobject *parent); 106 107 extern int __must_check kobject_rename(struct kobject *, const char *new_name); 108 extern int __must_check kobject_move(struct kobject *, struct kobject *); 109 110 extern struct kobject *kobject_get(struct kobject *kobj); 111 extern void kobject_put(struct kobject *kobj); 112 113 extern const void *kobject_namespace(struct kobject *kobj); 114 extern char *kobject_get_path(struct kobject *kobj, gfp_t flag); 115 116 struct kobj_type { 117 void (*release)(struct kobject *kobj); 118 const struct sysfs_ops *sysfs_ops; 119 struct attribute **default_attrs; 120 const struct kobj_ns_type_operations *(*child_ns_type)(struct kobject *kobj); 121 const void *(*namespace)(struct kobject *kobj); 122 }; 123 124 struct kobj_uevent_env { 125 char *argv[3]; 126 char *envp[UEVENT_NUM_ENVP]; 127 int envp_idx; 128 char buf[UEVENT_BUFFER_SIZE]; 129 int buflen; 130 }; 131 132 struct kset_uevent_ops { 133 int (* const filter)(struct kset *kset, struct kobject *kobj); 134 const char *(* const name)(struct kset *kset, struct kobject *kobj); 135 int (* const uevent)(struct kset *kset, struct kobject *kobj, 136 struct kobj_uevent_env *env); 137 }; 138 139 struct kobj_attribute { 140 struct attribute attr; 141 ssize_t (*show)(struct kobject *kobj, struct kobj_attribute *attr, 142 char *buf); 143 ssize_t (*store)(struct kobject *kobj, struct kobj_attribute *attr, 144 const char *buf, size_t count); 145 }; 146 147 extern const struct sysfs_ops kobj_sysfs_ops; 148 149 struct sock; 150 151 /** 152 * struct kset - a set of kobjects of a specific type, belonging to a specific subsystem. 153 * 154 * A kset defines a group of kobjects. They can be individually 155 * different "types" but overall these kobjects all want to be grouped 156 * together and operated on in the same manner. ksets are used to 157 * define the attribute callbacks and other common events that happen to 158 * a kobject. 159 * 160 * @list: the list of all kobjects for this kset 161 * @list_lock: a lock for iterating over the kobjects 162 * @kobj: the embedded kobject for this kset (recursion, isn't it fun...) 163 * @uevent_ops: the set of uevent operations for this kset. These are 164 * called whenever a kobject has something happen to it so that the kset 165 * can add new environment variables, or filter out the uevents if so 166 * desired. 167 */ 168 struct kset { 169 struct list_head list; 170 spinlock_t list_lock; 171 struct kobject kobj; 172 const struct kset_uevent_ops *uevent_ops; 173 }; 174 175 extern void kset_init(struct kset *kset); 176 extern int __must_check kset_register(struct kset *kset); 177 extern void kset_unregister(struct kset *kset); 178 extern struct kset * __must_check kset_create_and_add(const char *name, 179 const struct kset_uevent_ops *u, 180 struct kobject *parent_kobj); 181 182 static inline struct kset *to_kset(struct kobject *kobj) 183 { 184 return kobj ? container_of(kobj, struct kset, kobj) : NULL; 185 } 186 187 static inline struct kset *kset_get(struct kset *k) 188 { 189 return k ? to_kset(kobject_get(&k->kobj)) : NULL; 190 } 191 192 static inline void kset_put(struct kset *k) 193 { 194 kobject_put(&k->kobj); 195 } 196 197 static inline struct kobj_type *get_ktype(struct kobject *kobj) 198 { 199 return kobj->ktype; 200 } 201 202 extern struct kobject *kset_find_obj(struct kset *, const char *); 203 204 /* The global /sys/kernel/ kobject for people to chain off of */ 205 extern struct kobject *kernel_kobj; 206 /* The global /sys/kernel/mm/ kobject for people to chain off of */ 207 extern struct kobject *mm_kobj; 208 /* The global /sys/hypervisor/ kobject for people to chain off of */ 209 extern struct kobject *hypervisor_kobj; 210 /* The global /sys/power/ kobject for people to chain off of */ 211 extern struct kobject *power_kobj; 212 /* The global /sys/firmware/ kobject for people to chain off of */ 213 extern struct kobject *firmware_kobj; 214 215 int kobject_uevent(struct kobject *kobj, enum kobject_action action); 216 int kobject_uevent_env(struct kobject *kobj, enum kobject_action action, 217 char *envp[]); 218 219 __printf(2, 3) 220 int add_uevent_var(struct kobj_uevent_env *env, const char *format, ...); 221 222 int kobject_action_type(const char *buf, size_t count, 223 enum kobject_action *type); 224 225 #endif /* _KOBJECT_H_ */ 226