Add ext2 superblock, document file system
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+Bluejay Filesystem
+==================
+
+Filesystem drivers are still a work in progress. To test a file system you will
+want to create and mount a virtual block device. The makefile in ``src/kernel``
+will generate an ``hd0.img`` EXT2 disk image for you automatically. The default
+size is 32 megabytes, but you can create your own of any size if you want. Once
+the image has been created it will be loaded by QEMU automatically.
+
+In order to write to the virtual hard disk from your host operating system you
+should mount it. The ``make mount`` command in ``src/kernel`` mount the image to
+``$(BLUEJAY_ROOT)/mnt``. It will automatically give read and write permissions
+to the current user. This operation uses ``sudo`` internally, you will be
+prompted for your password.
+
+Virtual Filesystem
+------------------
+
+The Bluejay VFS is heavily inspired by UNIX. It relies on inodes and a tree of
+file nodes. The source can be found in ``src/kernel/vfs.c``. This also exports a
+very low-level API for dealing with files -- including the usual read(),
+write(), readdir(), etc -- but this should not be used for much longer. A high
+level API utilizing file descriptors will be implemented to make this simpler.