Date: Sun, 12 Jan 1997 23:20:09 +0100 From: j@uriah.heep.sax.de (J Wunsch) To: freebsd-hackers@freebsd.org Subject: Re: mount -o async on a news servre Message-ID: <Mutt.19970112232009.j@uriah.heep.sax.de> In-Reply-To: <199701122138.OAA26359@phaeton.artisoft.com>; from Terry Lambert on Jan 12, 1997 14:38:08 -0700 References: <Mutt.19970112214715.j@uriah.heep.sax.de> <199701122138.OAA26359@phaeton.artisoft.com>
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As Terry Lambert wrote:
> > You simply can't do this. Either, the drive reports a medium size, or
> > it doesn't. If it doesn't, you're at wits end: the drive could
> > support differently sized media as well, so you can't even guess which
> > one Terry will insert next. ;-)
>
> Oh?
>
> So then why is the OS even looking until it gets an insertion event?
Since you misinterpreting it. It doesn't wait for an `insertion
event' (since this doesn't exist at all).
> If the media isn't present, it has no business making observations
> about geometry in the first place.
Yes, that's an error.
> > > (ncr0:1:0): "iomega jaz 1GB G.60" type 0 removable SCSI 2
> > > sd1(ncr0:1:0): Direct-Access
> > > sd1(ncr0:1:0): FAST SCSI-2 100ns (10 Mb/sec) offset 8.
> > >
> > > sd1(ncr0:1:0): ILLEGAL REQUEST asc:24,0 Invalid field in CDB
> >
> > This one might be a FreeBSD driver problem. You can compile your
> > kernel with SCSIDEBUG enabled, to learn which SCSI command triggered
> > that problem.
>
> Mode sense on a drive it knows to (1) be removable and (2) to not have
> media inserted.
No. That doesn't make in invalid CDB, only a command returning with
an error status. Please, don't guess, but have a look. Or send me
the drive, so i can have a look. SCSIDEBUG is really your friend,
even though the flood of data is hard to read.
> > > (yes, the drive was spun up at the time, so you can't blame that).
> >
> > The drive was not read. It claimed the medium being not present. How
(ready)
> > should the driver know that there really was a medium in the drive, if
> > it claims wrong? (FreeBSD had a problem with devices saying ``Device
> > is in the process of becoming ready'', but i fixed this recently.)
>
> You are confusing the error on boot without media inserted with me
> explaining that the delay on umount was not the driver waiting for
> the drive to spin up.
No. I am not. The drive said ``Media not present''. That's it. It
didn't say ``...is in the process of becoming ready'' (which used to
be fatal in FreeBSD but is no longer).
> > (It doesn't even announce the arrival of a new medium unless you ask
> > for it, sadly.)
>
> I think you can have a request outstanding with a long timeout, which will
> be satisfied by insertion...
No. It will be aborted by the drive with a ``Device not ready'' (or
``Media not present'') error before. You either need that click click
click, or you have to live as it is. I prefer the latter.
--
cheers, J"org
joerg_wunsch@uriah.heep.sax.de -- http://www.sax.de/~joerg/ -- NIC: JW11-RIPE
Never trust an operating system you don't have sources for. ;-)
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