+struct atomic_notifier_head {
+ spinlock_t lock;
+ struct notifier_block *head;
+};
+
+struct blocking_notifier_head {
+ struct rw_semaphore rwsem;
+ struct notifier_block *head;
+};
+
+struct raw_notifier_head {
+ struct notifier_block *head;
+};
+
+struct srcu_notifier_head {
+ struct mutex mutex;
+ struct srcu_struct srcu;
+ struct notifier_block *head;
+};
+
+#define ATOMIC_INIT_NOTIFIER_HEAD(name) do { \
+ spin_lock_init(&(name)->lock); \
+ (name)->head = NULL; \
+ } while (0)
+#define BLOCKING_INIT_NOTIFIER_HEAD(name) do { \
+ init_rwsem(&(name)->rwsem); \
+ (name)->head = NULL; \
+ } while (0)
+#define RAW_INIT_NOTIFIER_HEAD(name) do { \
+ (name)->head = NULL; \
+ } while (0)
+
+/* srcu_notifier_heads must be initialized and cleaned up dynamically */
+extern void srcu_init_notifier_head(struct srcu_notifier_head *nh);
+#define srcu_cleanup_notifier_head(name) \
+ cleanup_srcu_struct(&(name)->srcu);
+
+#define ATOMIC_NOTIFIER_INIT(name) { \
+ .lock = __SPIN_LOCK_UNLOCKED(name.lock), \
+ .head = NULL }
+#define BLOCKING_NOTIFIER_INIT(name) { \
+ .rwsem = __RWSEM_INITIALIZER((name).rwsem), \
+ .head = NULL }
+#define RAW_NOTIFIER_INIT(name) { \
+ .head = NULL }
+/* srcu_notifier_heads cannot be initialized statically */
+
+#define ATOMIC_NOTIFIER_HEAD(name) \
+ struct atomic_notifier_head name = \
+ ATOMIC_NOTIFIER_INIT(name)
+#define BLOCKING_NOTIFIER_HEAD(name) \
+ struct blocking_notifier_head name = \
+ BLOCKING_NOTIFIER_INIT(name)
+#define RAW_NOTIFIER_HEAD(name) \
+ struct raw_notifier_head name = \
+ RAW_NOTIFIER_INIT(name)