dax: Reinstate RCU protection of inode

	return NULL;

}

/*

 * dax_lock_mapping_entry - Lock the DAX entry corresponding to a page

 * @page: The page whose entry we want to lock

 *

 * Context: Process context.

 * Return: %true if the entry was locked or does not need to be locked.

 */

bool dax_lock_mapping_entry(struct page *page)

{

	XA_STATE(xas, NULL, 0);

	void *entry;

	bool locked;

	/* Ensure page->mapping isn't freed while we look at it */

	rcu_read_lock();

	for (;;) {

		struct address_space *mapping = READ_ONCE(page->mapping);

		locked = false;

		if (!dax_mapping(mapping))

			return false;

			break;

		/*

		 * In the device-dax case there's no need to lock, a

		 * otherwise we would not have a valid pfn_to_page()

		 * translation.

		 */

		locked = true;

		if (S_ISCHR(mapping->host->i_mode))

			return true;

			break;

		xas.xa = &mapping->i_pages;

		xas_lock_irq(&xas);

		xas_set(&xas, page->index);

		entry = xas_load(&xas);

		if (dax_is_locked(entry)) {

			rcu_read_unlock();

			entry = get_unlocked_entry(&xas);

			xas_unlock_irq(&xas);

			rcu_read_lock();

			continue;

		}

		dax_lock_entry(&xas, entry);

		xas_unlock_irq(&xas);

		return true;

		break;

	}

	rcu_read_unlock();

	return locked;

}

void dax_unlock_mapping_entry(struct page *page)