splice: Use a folio in page_cache_pipe_buf_try_steal()

		struct pipe_buffer *buf)

{

	struct page *page = buf->page;

	struct folio *folio = page_folio(page);

	struct address_space *mapping;

	lock_page(page);

	folio_lock(folio);

	mapping = page_mapping(page);

	mapping = folio_mapping(folio);

	if (mapping) {

		WARN_ON(!PageUptodate(page));

		WARN_ON(!folio_test_uptodate(folio));

		/*

		 * At least for ext2 with nobh option, we need to wait on

		 * writeback completing on this page, since we'll remove it

		 * writeback completing on this folio, since we'll remove it

		 * from the pagecache.  Otherwise truncate wont wait on the

		 * page, allowing the disk blocks to be reused by someone else

		 * folio, allowing the disk blocks to be reused by someone else

		 * before we actually wrote our data to them. fs corruption

		 * ensues.

		 */

		wait_on_page_writeback(page);

		folio_wait_writeback(folio);

		if (page_has_private(page) &&

		    !try_to_release_page(page, GFP_KERNEL))

		if (folio_has_private(folio) &&

		    !filemap_release_folio(folio, GFP_KERNEL))

			goto out_unlock;

		/*

	}

	/*

	 * Raced with truncate or failed to remove page from current

	 * Raced with truncate or failed to remove folio from current

	 * address space, unlock and return failure.

	 */

out_unlock:

	unlock_page(page);

	folio_unlock(folio);

	return false;

}