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 #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 int kobject_set_name_vargs(struct kobject *kobj, const char *fmt, 84 va_list vargs); 85 86 static inline const char *kobject_name(const struct kobject *kobj) 87 { 88 return kobj->name; 89 } 90 91 extern void kobject_init(struct kobject *kobj, struct kobj_type *ktype); 92 extern __printf(3, 4) __must_check 93 int kobject_add(struct kobject *kobj, struct kobject *parent, 94 const char *fmt, ...); 95 extern __printf(4, 5) __must_check 96 int kobject_init_and_add(struct kobject *kobj, 97 struct kobj_type *ktype, struct kobject *parent, 98 const char *fmt, ...); 99 100 extern void kobject_del(struct kobject *kobj); 101 102 extern struct kobject * __must_check kobject_create(void); 103 extern struct kobject * __must_check kobject_create_and_add(const char *name, 104 struct kobject *parent); 105 106 extern int __must_check kobject_rename(struct kobject *, const char *new_name); 107 extern int __must_check kobject_move(struct kobject *, struct kobject *); 108 109 extern struct kobject *kobject_get(struct kobject *kobj); 110 extern void kobject_put(struct kobject *kobj); 111 112 extern const void *kobject_namespace(struct kobject *kobj); 113 extern char *kobject_get_path(struct kobject *kobj, gfp_t flag); 114 115 struct kobj_type { 116 void (*release)(struct kobject *kobj); 117 const struct sysfs_ops *sysfs_ops; 118 struct attribute **default_attrs; 119 const struct kobj_ns_type_operations *(*child_ns_type)(struct kobject *kobj); 120 const void *(*namespace)(struct kobject *kobj); 121 }; 122 123 struct kobj_uevent_env { 124 char *argv[3]; 125 char *envp[UEVENT_NUM_ENVP]; 126 int envp_idx; 127 char buf[UEVENT_BUFFER_SIZE]; 128 int buflen; 129 }; 130 131 struct kset_uevent_ops { 132 int (* const filter)(struct kset *kset, struct kobject *kobj); 133 const char *(* const name)(struct kset *kset, struct kobject *kobj); 134 int (* const uevent)(struct kset *kset, struct kobject *kobj, 135 struct kobj_uevent_env *env); 136 }; 137 138 struct kobj_attribute { 139 struct attribute attr; 140 ssize_t (*show)(struct kobject *kobj, struct kobj_attribute *attr, 141 char *buf); 142 ssize_t (*store)(struct kobject *kobj, struct kobj_attribute *attr, 143 const char *buf, size_t count); 144 }; 145 146 extern const struct sysfs_ops kobj_sysfs_ops; 147 148 struct sock; 149 150 /** 151 * struct kset - a set of kobjects of a specific type, belonging to a specific subsystem. 152 * 153 * A kset defines a group of kobjects. They can be individually 154 * different "types" but overall these kobjects all want to be grouped 155 * together and operated on in the same manner. ksets are used to 156 * define the attribute callbacks and other common events that happen to 157 * a kobject. 158 * 159 * @list: the list of all kobjects for this kset 160 * @list_lock: a lock for iterating over the kobjects 161 * @kobj: the embedded kobject for this kset (recursion, isn't it fun...) 162 * @uevent_ops: the set of uevent operations for this kset. These are 163 * called whenever a kobject has something happen to it so that the kset 164 * can add new environment variables, or filter out the uevents if so 165 * desired. 166 */ 167 struct kset { 168 struct list_head list; 169 spinlock_t list_lock; 170 struct kobject kobj; 171 const struct kset_uevent_ops *uevent_ops; 172 }; 173 174 extern void kset_init(struct kset *kset); 175 extern int __must_check kset_register(struct kset *kset); 176 extern void kset_unregister(struct kset *kset); 177 extern struct kset * __must_check kset_create_and_add(const char *name, 178 const struct kset_uevent_ops *u, 179 struct kobject *parent_kobj); 180 181 static inline struct kset *to_kset(struct kobject *kobj) 182 { 183 return kobj ? container_of(kobj, struct kset, kobj) : NULL; 184 } 185 186 static inline struct kset *kset_get(struct kset *k) 187 { 188 return k ? to_kset(kobject_get(&k->kobj)) : NULL; 189 } 190 191 static inline void kset_put(struct kset *k) 192 { 193 kobject_put(&k->kobj); 194 } 195 196 static inline struct kobj_type *get_ktype(struct kobject *kobj) 197 { 198 return kobj->ktype; 199 } 200 201 extern struct kobject *kset_find_obj(struct kset *, const char *); 202 203 /* The global /sys/kernel/ kobject for people to chain off of */ 204 extern struct kobject *kernel_kobj; 205 /* The global /sys/kernel/mm/ kobject for people to chain off of */ 206 extern struct kobject *mm_kobj; 207 /* The global /sys/hypervisor/ kobject for people to chain off of */ 208 extern struct kobject *hypervisor_kobj; 209 /* The global /sys/power/ kobject for people to chain off of */ 210 extern struct kobject *power_kobj; 211 /* The global /sys/firmware/ kobject for people to chain off of */ 212 extern struct kobject *firmware_kobj; 213 214 int kobject_uevent(struct kobject *kobj, enum kobject_action action); 215 int kobject_uevent_env(struct kobject *kobj, enum kobject_action action, 216 char *envp[]); 217 218 __printf(2, 3) 219 int add_uevent_var(struct kobj_uevent_env *env, const char *format, ...); 220 221 int kobject_action_type(const char *buf, size_t count, 222 enum kobject_action *type); 223 224 #endif /* _KOBJECT_H_ */ 225