Re: Interface for SCSI transactions ?

[Svante Signell]

Hi again, a few months later.

On Sat, 2011-12-10 at 09:38 +0100, Thomas Schmitt wrote:
> Hi,
> 
> > Don't you have any time any longer for working on this? I/we understand
> > if you don't, but no reply since October 17 makes one wonder.
> 
> Well, actually i was waiting for a decision what RPC layout to use.
> 
> Meanwhile i explored the opportunities to operate a real CD drive from
> a qemu guest. With GNU/Linux it would work quite well
>   http://libburnia-project.org/wiki/QemuXorriso
>   
> But all workable device configurations deliver an SCSI drive or
> a virtio device. I understand the latter has no support in GNU/Hurd at
> all, whereas the SCSI device emulates a controller which my copy of
> GNU/Hurd does not know.
> 
> When i was up to exploring how to hack in Hurd, i got the unexpected
> opportunity to learn from libcdio mailing list how to produce, write
> and read CD-TEXT for audio CDs. That's a long standing item on my
> todo list. (Another one is UDF. Hurd has the potential to become such
> an item, too.)
> 
> I plan to revisit the CD-on-Hurd topic when i'm done with CD-TEXT.
> I could still need a tutor then, who leads me through the development
> cycle of Hurd, although i have some instructions from this list
> somewhere in my mailbox.

Are you finished with the CD-TEXT stuff by now? More hands would be
appreciated. I hope the tutors would be the people helping you out
previously, mainly Samuel and Olaf. 

> Hurd has the same strange influence on me as UDF. Whenever i begin
> to work on it, there pop up distractions. I stumbled into the test party
> of qemu 1.0, and over the ongoing work of Leon Merten Lohse in libcdio.
> So probably i would have to begin UDF again in order to induce progress
> with my Hurd plans.
> (CD-TEXT docs are proprietary but understandable, if one puts together
>  the few public snippets. UDF docs are public and free, but structured
>  to chase away the reader. There are two interleaved specs, ECMA-167 and
>  UDF-2.60.)

How much is UDF used nowadays?

> Other than with CD-TEXT and UDF, there has never been a user request for
> CD burning on Hurd. So it is a total pet project of mine, motivated
> only by me being maintainer of a GNU project that is not yet completely
> operational on the GNU operating system with GNU kernel.
> I still have to learn a lot before i can handle the whole vertical
> stack from emulated or passed-through hardware to Hurd userspace.
> (It's so dark and lonely down there in the Linux 2.0 driver dungeon.)

The network drivers are now using DDE and probably SATA soon (Samuel?).
So maybe DDE would be a way forward also for SCSI.