These modules provide interfaces to be used directly from userspace : raw character access , raw block access , ftl flash transition layer - a type of filesystem used on flash , and jfs or journaled file system - which provides a filesystem directly on the flash rather than emulating a block device 這些模塊提供從用戶空間直接使用的接口:原始字符訪問、原始塊訪問、 ftl (閃存轉(zhuǎn)換層, flash transition layer用在閃存上的一種文件系統(tǒng))和jfs (即日志文件系統(tǒng), journaled file system在閃存上直接提供文件系統(tǒng)而不是模擬塊設(shè)備) 。