From owner-freebsd-current Fri May 29 13:21:48 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id NAA29797 for freebsd-current-outgoing; Fri, 29 May 1998 13:21:48 -0700 (PDT) (envelope-from owner-freebsd-current@FreeBSD.ORG) Received: from dingo.cdrom.com (dingo.cdrom.com [204.216.28.145]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id NAA29784 for ; Fri, 29 May 1998 13:21:46 -0700 (PDT) (envelope-from mike@dingo.cdrom.com) Received: from dingo.cdrom.com (localhost [127.0.0.1]) by dingo.cdrom.com (8.8.8/8.8.5) with ESMTP id MAA00509; Fri, 29 May 1998 12:15:53 -0700 (PDT) Message-Id: <199805291915.MAA00509@dingo.cdrom.com> X-Mailer: exmh version 2.0zeta 7/24/97 To: Joerg Schilling cc: mike@smith.net.au, freebsd-current@FreeBSD.ORG Subject: Re: cdrecord trouble on currnet / SCSI ABI test In-reply-to: Your message of "Fri, 29 May 1998 19:20:10 +0200." <199805291720.TAA15036@sherwood.gmd.de> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Date: Fri, 29 May 1998 12:15:53 -0700 From: Mike Smith Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by hub.freebsd.org id NAA29787 Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > >> The scg drvier which I wrote in 1986 is based on this interface and > >> itself is the base for my portable SCSI user-level command transport > >> system. It should be faily easy to make a CAM adoption layer for scg. > > >It was. The real problems with scg have to do with the lack of visible > >documentation. It is unclear how to do any sort of meaningful error > >handling, or whether this should be managed at a lower level. Again, > >this is an issue I was postponing until I had established that > >everything else was going to behave and the interface had stabilised. > > The main problem with this documentation is that a hacker who wants to > contribute code must have thorough knowledge on the SCSI protocol to > understand what to do from reading simply a API doc. Actually, they shouldn't. Your scg stack passes SCSI commands down, and expects them to be handled according to a set of rules. The interface shim has to provide a translation between those rules and the rules that the host system advertises. > For this reason, I prefer to have some ABI checker software. Alan Turing. > But for timeout tests not every CD-ROM drive is usable because the only > idea I currently have to force a SCSI timeout is to do one very big > SCSi-VERIFY on a disk with > 400MB data on it. This is because not all > timeout implementations catch timeouts fast (< 1 minute). Build a small board containing a 5380 and a microcontroller. Write some minimal SCSI target software, and put a console on it. You could probably sell 5-10 of these to SCSI driver authors. -- \\ Sometimes you're ahead, \\ Mike Smith \\ sometimes you're behind. \\ mike@smith.net.au \\ The race is long, and in the \\ msmith@freebsd.org \\ end it's only with yourself. \\ msmith@cdrom.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message