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 char *kobject_get_path(struct kobject *kobj, gfp_t flag); 111 112 struct kobj_type { 113 void (*release)(struct kobject *kobj); 114 const struct sysfs_ops *sysfs_ops; 115 struct attribute **default_attrs; 116 const struct kobj_ns_type_operations *(*child_ns_type)(struct kobject *kobj); 117 const void *(*namespace)(struct kobject *kobj); 118 }; 119 120 struct kobj_uevent_env { 121 char *envp[UEVENT_NUM_ENVP]; 122 int envp_idx; 123 char buf[UEVENT_BUFFER_SIZE]; 124 int buflen; 125 }; 126 127 struct kset_uevent_ops { 128 int (* const filter)(struct kset *kset, struct kobject *kobj); 129 const char *(* const name)(struct kset *kset, struct kobject *kobj); 130 int (* const uevent)(struct kset *kset, struct kobject *kobj, 131 struct kobj_uevent_env *env); 132 }; 133 134 struct kobj_attribute { 135 struct attribute attr; 136 ssize_t (*show)(struct kobject *kobj, struct kobj_attribute *attr, 137 char *buf); 138 ssize_t (*store)(struct kobject *kobj, struct kobj_attribute *attr, 139 const char *buf, size_t count); 140 }; 141 142 extern const struct sysfs_ops kobj_sysfs_ops; 143 144 struct sock; 145 146 /** 147 * struct kset - a set of kobjects of a specific type, belonging to a specific subsystem. 148 * 149 * A kset defines a group of kobjects. They can be individually 150 * different "types" but overall these kobjects all want to be grouped 151 * together and operated on in the same manner. ksets are used to 152 * define the attribute callbacks and other common events that happen to 153 * a kobject. 154 * 155 * @list: the list of all kobjects for this kset 156 * @list_lock: a lock for iterating over the kobjects 157 * @kobj: the embedded kobject for this kset (recursion, isn't it fun...) 158 * @uevent_ops: the set of uevent operations for this kset. These are 159 * called whenever a kobject has something happen to it so that the kset 160 * can add new environment variables, or filter out the uevents if so 161 * desired. 162 */ 163 struct kset { 164 struct list_head list; 165 spinlock_t list_lock; 166 struct kobject kobj; 167 const struct kset_uevent_ops *uevent_ops; 168 }; 169 170 extern void kset_init(struct kset *kset); 171 extern int __must_check kset_register(struct kset *kset); 172 extern void kset_unregister(struct kset *kset); 173 extern struct kset * __must_check kset_create_and_add(const char *name, 174 const struct kset_uevent_ops *u, 175 struct kobject *parent_kobj); 176 177 static inline struct kset *to_kset(struct kobject *kobj) 178 { 179 return kobj ? container_of(kobj, struct kset, kobj) : NULL; 180 } 181 182 static inline struct kset *kset_get(struct kset *k) 183 { 184 return k ? to_kset(kobject_get(&k->kobj)) : NULL; 185 } 186 187 static inline void kset_put(struct kset *k) 188 { 189 kobject_put(&k->kobj); 190 } 191 192 static inline struct kobj_type *get_ktype(struct kobject *kobj) 193 { 194 return kobj->ktype; 195 } 196 197 extern struct kobject *kset_find_obj(struct kset *, const char *); 198 199 /* The global /sys/kernel/ kobject for people to chain off of */ 200 extern struct kobject *kernel_kobj; 201 /* The global /sys/kernel/mm/ kobject for people to chain off of */ 202 extern struct kobject *mm_kobj; 203 /* The global /sys/hypervisor/ kobject for people to chain off of */ 204 extern struct kobject *hypervisor_kobj; 205 /* The global /sys/power/ kobject for people to chain off of */ 206 extern struct kobject *power_kobj; 207 /* The global /sys/firmware/ kobject for people to chain off of */ 208 extern struct kobject *firmware_kobj; 209 210 int kobject_uevent(struct kobject *kobj, enum kobject_action action); 211 int kobject_uevent_env(struct kobject *kobj, enum kobject_action action, 212 char *envp[]); 213 214 __printf(2, 3) 215 int add_uevent_var(struct kobj_uevent_env *env, const char *format, ...); 216 217 int kobject_action_type(const char *buf, size_t count, 218 enum kobject_action *type); 219 220 #endif /* _KOBJECT_H_ */ 221