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 30 #define UEVENT_HELPER_PATH_LEN 256 31 #define UEVENT_NUM_ENVP 32 /* number of env pointers */ 32 #define UEVENT_BUFFER_SIZE 2048 /* buffer for the variables */ 33 34 /* path to the userspace helper executed on an event */ 35 extern char uevent_helper[]; 36 37 /* counter to tag the uevent, read only except for the kobject core */ 38 extern u64 uevent_seqnum; 39 40 /* 41 * The actions here must match the index to the string array 42 * in lib/kobject_uevent.c 43 * 44 * Do not add new actions here without checking with the driver-core 45 * maintainers. Action strings are not meant to express subsystem 46 * or device specific properties. In most cases you want to send a 47 * kobject_uevent_env(kobj, KOBJ_CHANGE, env) with additional event 48 * specific variables added to the event environment. 49 */ 50 enum kobject_action { 51 KOBJ_ADD, 52 KOBJ_REMOVE, 53 KOBJ_CHANGE, 54 KOBJ_MOVE, 55 KOBJ_ONLINE, 56 KOBJ_OFFLINE, 57 KOBJ_MAX 58 }; 59 60 struct kobject { 61 const char *name; 62 struct list_head entry; 63 struct kobject *parent; 64 struct kset *kset; 65 struct kobj_type *ktype; 66 struct sysfs_dirent *sd; 67 struct kref kref; 68 unsigned int state_initialized:1; 69 unsigned int state_in_sysfs:1; 70 unsigned int state_add_uevent_sent:1; 71 unsigned int state_remove_uevent_sent:1; 72 unsigned int uevent_suppress:1; 73 }; 74 75 extern __printf(2, 3) 76 int kobject_set_name(struct kobject *kobj, const char *name, ...); 77 extern int kobject_set_name_vargs(struct kobject *kobj, const char *fmt, 78 va_list vargs); 79 80 static inline const char *kobject_name(const struct kobject *kobj) 81 { 82 return kobj->name; 83 } 84 85 extern void kobject_init(struct kobject *kobj, struct kobj_type *ktype); 86 extern __printf(3, 4) __must_check 87 int kobject_add(struct kobject *kobj, struct kobject *parent, 88 const char *fmt, ...); 89 extern __printf(4, 5) __must_check 90 int kobject_init_and_add(struct kobject *kobj, 91 struct kobj_type *ktype, struct kobject *parent, 92 const char *fmt, ...); 93 94 extern void kobject_del(struct kobject *kobj); 95 96 extern struct kobject * __must_check kobject_create(void); 97 extern struct kobject * __must_check kobject_create_and_add(const char *name, 98 struct kobject *parent); 99 100 extern int __must_check kobject_rename(struct kobject *, const char *new_name); 101 extern int __must_check kobject_move(struct kobject *, struct kobject *); 102 103 extern struct kobject *kobject_get(struct kobject *kobj); 104 extern void kobject_put(struct kobject *kobj); 105 106 extern char *kobject_get_path(struct kobject *kobj, gfp_t flag); 107 108 struct kobj_type { 109 void (*release)(struct kobject *kobj); 110 const struct sysfs_ops *sysfs_ops; 111 struct attribute **default_attrs; 112 const struct kobj_ns_type_operations *(*child_ns_type)(struct kobject *kobj); 113 const void *(*namespace)(struct kobject *kobj); 114 }; 115 116 struct kobj_uevent_env { 117 char *envp[UEVENT_NUM_ENVP]; 118 int envp_idx; 119 char buf[UEVENT_BUFFER_SIZE]; 120 int buflen; 121 }; 122 123 struct kset_uevent_ops { 124 int (* const filter)(struct kset *kset, struct kobject *kobj); 125 const char *(* const name)(struct kset *kset, struct kobject *kobj); 126 int (* const uevent)(struct kset *kset, struct kobject *kobj, 127 struct kobj_uevent_env *env); 128 }; 129 130 struct kobj_attribute { 131 struct attribute attr; 132 ssize_t (*show)(struct kobject *kobj, struct kobj_attribute *attr, 133 char *buf); 134 ssize_t (*store)(struct kobject *kobj, struct kobj_attribute *attr, 135 const char *buf, size_t count); 136 }; 137 138 extern const struct sysfs_ops kobj_sysfs_ops; 139 140 struct sock; 141 142 /** 143 * struct kset - a set of kobjects of a specific type, belonging to a specific subsystem. 144 * 145 * A kset defines a group of kobjects. They can be individually 146 * different "types" but overall these kobjects all want to be grouped 147 * together and operated on in the same manner. ksets are used to 148 * define the attribute callbacks and other common events that happen to 149 * a kobject. 150 * 151 * @list: the list of all kobjects for this kset 152 * @list_lock: a lock for iterating over the kobjects 153 * @kobj: the embedded kobject for this kset (recursion, isn't it fun...) 154 * @uevent_ops: the set of uevent operations for this kset. These are 155 * called whenever a kobject has something happen to it so that the kset 156 * can add new environment variables, or filter out the uevents if so 157 * desired. 158 */ 159 struct kset { 160 struct list_head list; 161 spinlock_t list_lock; 162 struct kobject kobj; 163 const struct kset_uevent_ops *uevent_ops; 164 }; 165 166 extern void kset_init(struct kset *kset); 167 extern int __must_check kset_register(struct kset *kset); 168 extern void kset_unregister(struct kset *kset); 169 extern struct kset * __must_check kset_create_and_add(const char *name, 170 const struct kset_uevent_ops *u, 171 struct kobject *parent_kobj); 172 173 static inline struct kset *to_kset(struct kobject *kobj) 174 { 175 return kobj ? container_of(kobj, struct kset, kobj) : NULL; 176 } 177 178 static inline struct kset *kset_get(struct kset *k) 179 { 180 return k ? to_kset(kobject_get(&k->kobj)) : NULL; 181 } 182 183 static inline void kset_put(struct kset *k) 184 { 185 kobject_put(&k->kobj); 186 } 187 188 static inline struct kobj_type *get_ktype(struct kobject *kobj) 189 { 190 return kobj->ktype; 191 } 192 193 extern struct kobject *kset_find_obj(struct kset *, const char *); 194 195 /* The global /sys/kernel/ kobject for people to chain off of */ 196 extern struct kobject *kernel_kobj; 197 /* The global /sys/kernel/mm/ kobject for people to chain off of */ 198 extern struct kobject *mm_kobj; 199 /* The global /sys/hypervisor/ kobject for people to chain off of */ 200 extern struct kobject *hypervisor_kobj; 201 /* The global /sys/power/ kobject for people to chain off of */ 202 extern struct kobject *power_kobj; 203 /* The global /sys/firmware/ kobject for people to chain off of */ 204 extern struct kobject *firmware_kobj; 205 206 #if defined(CONFIG_HOTPLUG) 207 int kobject_uevent(struct kobject *kobj, enum kobject_action action); 208 int kobject_uevent_env(struct kobject *kobj, enum kobject_action action, 209 char *envp[]); 210 211 __printf(2, 3) 212 int add_uevent_var(struct kobj_uevent_env *env, const char *format, ...); 213 214 int kobject_action_type(const char *buf, size_t count, 215 enum kobject_action *type); 216 #else 217 static inline int kobject_uevent(struct kobject *kobj, 218 enum kobject_action action) 219 { return 0; } 220 static inline int kobject_uevent_env(struct kobject *kobj, 221 enum kobject_action action, 222 char *envp[]) 223 { return 0; } 224 225 static inline __printf(2, 3) 226 int add_uevent_var(struct kobj_uevent_env *env, const char *format, ...) 227 { return 0; } 228 229 static inline int kobject_action_type(const char *buf, size_t count, 230 enum kobject_action *type) 231 { return -EINVAL; } 232 #endif 233 234 #endif /* _KOBJECT_H_ */ 235