Device interfaces (was: USB Mass Storage with rump)

[Olaf Buddenhagen]

Hi,

On Thu, Sep 24, 2015 at 09:30:17AM +0200, Samuel Thibault wrote:
> Olaf Buddenhagen, le Thu 24 Sep 2015 00:11:26 +0200, a écrit :

> > As I already mentioned on IRC, I don't think we should emulate Mach
> > device nodes at all here. Rather, the USB mass storage server(s) would
> > export UNIX device nodes, which ext2fs/libstore can already deal with
> > AFAIK.
> 
> But the fs RPC interface is much more involved to implement than the
> device RPC interface.

Is it really? While I haven't implemented a trivfs translator doing
actual file I/O yet, they do seem simple enough to me... Or am I missing
something?

Also, it's a one-time effort. And it avoids the need to modify
libstore/storeio.

> Storeio already does the conversion nicely, why not reusing it?

Why introduce an unnecessary indirection, which makes things more
confusing and harder to use, if we can just use the standard Hurd I/O
interface directly?

The point of the store infrastructure is to abstract different backends,
so we are not bound to Mach devices only...

-antrik-