the DragonFly VFS

[evs]

Filesystems are largely self-contained however, porting them from one
OS to another is not easy because even if the source OS has a VFS, the
interface may be very different from the target OSs VFS, such as the
differences between the Linux VFS and the FreeBSD VFS. 

What if DragonFly had a VFS for the VFS? A virtual-virtual
filesystem? Its purpose would be to support multiple VFS interfaces:
Linux, FreeBSD, others, and it's own. The goal of this would be to
make the porting of filesystems to Dragonfly as trivial as possible
and allow the comparison of different filesystem implementations on a
level playing field.

Any comments are welcome.