Date: Fri, 5 May 1995 17:28:13 -0700 (PDT) From: Julian Elischer <julian@ref.tfs.com> To: fredriks@mcs.com (Lars Fredriksen) Cc: dufault@hda.com, bde@zeta.org.au, hackers@FreeBSD.org, julian@FreeBSD.org Subject: Re: SLICES and bits in the device numbers Message-ID: <199505060028.RAA04681@ref.tfs.com> In-Reply-To: <m0s7Q1e-0003kwC@mercury.mcs.com> from "Lars Fredriksen" at May 5, 95 11:14:46 am
next in thread | previous in thread | raw e-mail | index | archive | help
> > Couldn't we use the "bus" device for all lowlevel stuff like formatting, > tuning, tape fixing etc? What I mean is that we open /dev/scsi0 and > blast the scsi request straight in that way. It does mean some code > duplication between the different drivers and the "control" program, > but if we are running out of bits, it might be worth it. but you couldn't blast a format at sd0 but at sb0t0l0 or whatever, which might be easier to get wrong? my own suggestion is that slice1 (presently whole disk slice) be divided into a couple of sub-devices.. 0: whole disk 1: MBR block (if it exists) 2: control (ioctl only) device the st driver already has a control device.. What a control device actually means is dependent on the kind of device, (setting modes permanently on tapes is one example) so I see no reason to not make it's definition device specific, unless you want to make teh SCSI code define this.. (which may not be what we want) julian
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199505060028.RAA04681>