-
-/**
- * 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);
- return ret;
-}
-
-EXPORT_SYMBOL_GPL(srcu_notifier_chain_register);
-
-/**
- * srcu_notifier_chain_unregister - Remove notifier from an SRCU notifier chain
- * @nh: Pointer to head of the SRCU notifier chain
- * @n: Entry to remove from notifier chain
- *
- * Removes a notifier from an SRCU notifier chain.
- * Must be called from process context.
- *
- * Returns zero on success or %-ENOENT on failure.
- */
-int srcu_notifier_chain_unregister(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_unregister(&nh->head, n);
-
- mutex_lock(&nh->mutex);
- ret = notifier_chain_unregister(&nh->head, n);
- mutex_unlock(&nh->mutex);
- synchronize_srcu(&nh->srcu);
- return ret;
-}
-
-EXPORT_SYMBOL_GPL(srcu_notifier_chain_unregister);
-
-/**
- * srcu_notifier_call_chain - Call functions in an SRCU notifier chain
- * @nh: Pointer to head of the SRCU 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 a process context, so they are allowed to block.
- *
- * If the return value of the notifier can be and'ed
- * with %NOTIFY_STOP_MASK then srcu_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 srcu_notifier_call_chain(struct srcu_notifier_head *nh,
- unsigned long val, void *v)
-{
- int ret;
- int idx;
-
- idx = srcu_read_lock(&nh->srcu);
- ret = notifier_call_chain(&nh->head, val, v);
- srcu_read_unlock(&nh->srcu, idx);
- return ret;
-}
-
-EXPORT_SYMBOL_GPL(srcu_notifier_call_chain);
-
-/**
- * srcu_init_notifier_head - Initialize an SRCU notifier head
- * @nh: Pointer to head of the srcu notifier chain
- *
- * Unlike other sorts of notifier heads, SRCU notifier heads require
- * dynamic initialization. Be sure to call this routine before
- * calling any of the other SRCU notifier routines for this head.
- *
- * If an SRCU notifier head is deallocated, it must first be cleaned
- * up by calling srcu_cleanup_notifier_head(). Otherwise the head's
- * per-cpu data (used by the SRCU mechanism) will leak.
- */
-
-void srcu_init_notifier_head(struct srcu_notifier_head *nh)
-{
- mutex_init(&nh->mutex);
- if (init_srcu_struct(&nh->srcu) < 0)
- BUG();
- nh->head = NULL;
-}
-
-EXPORT_SYMBOL_GPL(srcu_init_notifier_head);
-
-/**
- * register_reboot_notifier - Register function to be called at reboot time
- * @nb: Info about notifier function to be called
- *
- * Registers a function with the list of functions
- * to be called at reboot time.
- *
- * Currently always returns zero, as blocking_notifier_chain_register
- * always returns zero.
- */
-
-int register_reboot_notifier(struct notifier_block * nb)
-{
- return blocking_notifier_chain_register(&reboot_notifier_list, nb);
-}
-
-EXPORT_SYMBOL(register_reboot_notifier);
-
-/**
- * unregister_reboot_notifier - Unregister previously registered reboot notifier
- * @nb: Hook to be unregistered
- *
- * Unregisters a previously registered reboot
- * notifier function.
- *
- * Returns zero on success, or %-ENOENT on failure.
- */
-
-int unregister_reboot_notifier(struct notifier_block * nb)
-{
- return blocking_notifier_chain_unregister(&reboot_notifier_list, nb);
-}
-
-EXPORT_SYMBOL(unregister_reboot_notifier);
-