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 kernfs_node *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 *argv[3]; 123 char *envp[UEVENT_NUM_ENVP]; 124 int envp_idx; 125 char buf[UEVENT_BUFFER_SIZE]; 126 int buflen; 127 }; 128 129 struct kset_uevent_ops { 130 int (* const filter)(struct kset *kset, struct kobject *kobj); 131 const char *(* const name)(struct kset *kset, struct kobject *kobj); 132 int (* const uevent)(struct kset *kset, struct kobject *kobj, 133 struct kobj_uevent_env *env); 134 }; 135 136 struct kobj_attribute { 137 struct attribute attr; 138 ssize_t (*show)(struct kobject *kobj, struct kobj_attribute *attr, 139 char *buf); 140 ssize_t (*store)(struct kobject *kobj, struct kobj_attribute *attr, 141 const char *buf, size_t count); 142 }; 143 144 extern const struct sysfs_ops kobj_sysfs_ops; 145 146 struct sock; 147 148 /** 149 * struct kset - a set of kobjects of a specific type, belonging to a specific subsystem. 150 * 151 * A kset defines a group of kobjects. They can be individually 152 * different "types" but overall these kobjects all want to be grouped 153 * together and operated on in the same manner. ksets are used to 154 * define the attribute callbacks and other common events that happen to 155 * a kobject. 156 * 157 * @list: the list of all kobjects for this kset 158 * @list_lock: a lock for iterating over the kobjects 159 * @kobj: the embedded kobject for this kset (recursion, isn't it fun...) 160 * @uevent_ops: the set of uevent operations for this kset. These are 161 * called whenever a kobject has something happen to it so that the kset 162 * can add new environment variables, or filter out the uevents if so 163 * desired. 164 */ 165 struct kset { 166 struct list_head list; 167 spinlock_t list_lock; 168 struct kobject kobj; 169 const struct kset_uevent_ops *uevent_ops; 170 }; 171 172 extern void kset_init(struct kset *kset); 173 extern int __must_check kset_register(struct kset *kset); 174 extern void kset_unregister(struct kset *kset); 175 extern struct kset * __must_check kset_create_and_add(const char *name, 176 const struct kset_uevent_ops *u, 177 struct kobject *parent_kobj); 178 179 static inline struct kset *to_kset(struct kobject *kobj) 180 { 181 return kobj ? container_of(kobj, struct kset, kobj) : NULL; 182 } 183 184 static inline struct kset *kset_get(struct kset *k) 185 { 186 return k ? to_kset(kobject_get(&k->kobj)) : NULL; 187 } 188 189 static inline void kset_put(struct kset *k) 190 { 191 kobject_put(&k->kobj); 192 } 193 194 static inline struct kobj_type *get_ktype(struct kobject *kobj) 195 { 196 return kobj->ktype; 197 } 198 199 extern struct kobject *kset_find_obj(struct kset *, const char *); 200 201 /* The global /sys/kernel/ kobject for people to chain off of */ 202 extern struct kobject *kernel_kobj; 203 /* The global /sys/kernel/mm/ kobject for people to chain off of */ 204 extern struct kobject *mm_kobj; 205 /* The global /sys/hypervisor/ kobject for people to chain off of */ 206 extern struct kobject *hypervisor_kobj; 207 /* The global /sys/power/ kobject for people to chain off of */ 208 extern struct kobject *power_kobj; 209 /* The global /sys/firmware/ kobject for people to chain off of */ 210 extern struct kobject *firmware_kobj; 211 212 int kobject_uevent(struct kobject *kobj, enum kobject_action action); 213 int kobject_uevent_env(struct kobject *kobj, enum kobject_action action, 214 char *envp[]); 215 216 __printf(2, 3) 217 int add_uevent_var(struct kobj_uevent_env *env, const char *format, ...); 218 219 int kobject_action_type(const char *buf, size_t count, 220 enum kobject_action *type); 221 222 #endif /* _KOBJECT_H_ */ 223