????????VFS????
????1??VFS
????????????????????????????????????????????????з???vfs???????????????????????y?????open??read??write??????o??????????????????????read??write??????????????????????????

????2??VFS???????
????VFS?????????????????????????????????????????VFS????????????????????Щ???????????????????????????????????????У?vfs?????????????????????????????linux????ò??÷?????????????vfs????????ε??????????????vfs????????????Щ???豸???????????????vfs???????
????3??VFS????
????3.1??procfs
????3.2??sysfs
????3.3??cpusetfs
????3.4??ntfs
????3.5??extX
????3.6???????????????
???????????????????????????switch??????????????????????????????file_operations?????????????????linux?У??????洢??б??????????????в??????????????linux?е?????е????????洢?????proc??????е????????????????read???????????????????????????????????????????????????仯??linux??????б???????????????洢????
????4????????????
????????linux?????????????????????????????????????????а?????????????????У??????????????????????????????????????????????????????linux?????????????????????????????????????????????????????????linux?????initrd?й?????????????????????????????????????????????????????????????????????????