On 9/2/07, David Nicol <davidnicol@gmail.com> wrote:

My naive and ignorant presumption is that initfs sets up the file
system structure at a higher level -- perhaps the virtual file system that
linux uses to make all the file systems behave the same -- rather than
going through the whole dance of pretending that the data in question is
really on some kind of external media that has to be mounted and so on.
Not alert enough at this point to construct a nice metaphor.

VFS doesn't take away the lower level of mounting a file system, it's a layer of abstraction that hides the details of the process. (This is a Very Good Thing, because it allows the code for managing files, directories, pipes, etc. to be written once at the top layer, a second layer to handle logical representation schemes, and a lower layer to work with the physical hardware.) There's still got to be a device, a driver, and the low-level code that knows about the actual representation of the filesystems on whatever media they occupy.