1 - virtual directories, reading a directory wipes out the
2 virtual directory. virtual property in the inode.
4 - inode contains the qid, inuse, pointers, and virtual
5 property. one pointer each for 3 levels.
7 ? reserve version == -1 to mean a virtual file? makes
10 - first inode is always the root.
12 - adding any virtual entry to a directory makes the
13 whole directory virtual.
15 ? how do we keep cfs from swapping?
17 ? how do we resolve access to missing parts when running
20 ? what are default properties of files (ones we haven't