+ down_read(&nh->rwsem);
+ ret = notifier_call_chain(&nh->head, val, v);
+ up_read(&nh->rwsem);
+ return ret;
+}
+
+EXPORT_SYMBOL_GPL(blocking_notifier_call_chain);
+
+/*
+ * Raw notifier chain routines. There is no protection;
+ * the caller must provide it. Use at your own risk!
+ */
+
+/**
+ * raw_notifier_chain_register - Add notifier to a raw notifier chain
+ * @nh: Pointer to head of the raw notifier chain
+ * @n: New entry in notifier chain
+ *
+ * Adds a notifier to a raw notifier chain.
+ * All locking must be provided by the caller.
+ *
+ * Currently always returns zero.
+ */
+
+int raw_notifier_chain_register(struct raw_notifier_head *nh,
+ struct notifier_block *n)
+{
+ return notifier_chain_register(&nh->head, n);
+}
+
+EXPORT_SYMBOL_GPL(raw_notifier_chain_register);
+
+/**
+ * raw_notifier_chain_unregister - Remove notifier from a raw notifier chain
+ * @nh: Pointer to head of the raw notifier chain
+ * @n: Entry to remove from notifier chain
+ *
+ * Removes a notifier from a raw notifier chain.
+ * All locking must be provided by the caller.
+ *
+ * Returns zero on success or %-ENOENT on failure.
+ */
+int raw_notifier_chain_unregister(struct raw_notifier_head *nh,
+ struct notifier_block *n)
+{
+ return notifier_chain_unregister(&nh->head, n);
+}
+
+EXPORT_SYMBOL_GPL(raw_notifier_chain_unregister);
+
+/**
+ * raw_notifier_call_chain - Call functions in a raw notifier chain
+ * @nh: Pointer to head of the raw notifier chain
+ * @val: Value passed unmodified to notifier function
+ * @v: Pointer passed unmodified to notifier function
+ *
+ * Calls each function in a notifier chain in turn. The functions
+ * run in an undefined context.
+ * All locking must be provided by the caller.
+ *
+ * If the return value of the notifier can be and'ed
+ * with %NOTIFY_STOP_MASK then raw_notifier_call_chain
+ * will return immediately, with the return value of
+ * the notifier function which halted execution.
+ * Otherwise the return value is the return value
+ * of the last notifier function called.
+ */
+
+int raw_notifier_call_chain(struct raw_notifier_head *nh,
+ unsigned long val, void *v)
+{
+ return notifier_call_chain(&nh->head, val, v);
+}
+
+EXPORT_SYMBOL_GPL(raw_notifier_call_chain);
+
+/*
+ * SRCU notifier chain routines. Registration and unregistration
+ * use a mutex, and call_chain is synchronized by SRCU (no locks).
+ */
+
+/**
+ * srcu_notifier_chain_register - Add notifier to an SRCU notifier chain
+ * @nh: Pointer to head of the SRCU notifier chain
+ * @n: New entry in notifier chain
+ *
+ * Adds a notifier to an SRCU notifier chain.
+ * Must be called in process context.
+ *
+ * Currently always returns zero.
+ */
+
+int srcu_notifier_chain_register(struct srcu_notifier_head *nh,
+ struct notifier_block *n)
+{
+ int ret;
+
+ /*
+ * This code gets used during boot-up, when task switching is
+ * not yet working and interrupts must remain disabled. At
+ * such times we must not call mutex_lock().
+ */
+ if (unlikely(system_state == SYSTEM_BOOTING))
+ return notifier_chain_register(&nh->head, n);
+
+ mutex_lock(&nh->mutex);
+ ret = notifier_chain_register(&nh->head, n);
+ mutex_unlock(&nh->mutex);