Subject: Re: AIC7XXX driver - No Tape support for writing?
To: Gerald C. Simmons <firstname.lastname@example.org>
From: Jason Thorpe <email@example.com>
Date: 11/07/1997 10:34:14
On Thu, 6 Nov 1997 09:15:42 -0800 (PST)
"Gerald C. Simmons" <firstname.lastname@example.org> wrote:
> I've done some further investigating and I'm suspecting there is no "write
> support" in the Adaptec AIC7XXX drivers, or at least the 2842VL.
Um, how can there possibly be "no write support"?
> I tried the following: "tar cvf /dev/st0 <directory>" with my Archive 150
> attached to an AHA2842VL controller. The Tape LED came on, tar went about it's
> business with NO ERRORS, but the drive NEVER made a move. It was as if tar was
> dumping to /dev/null.
> I checked all the -current files for the AIC7XXX and ahc_isa.c drivers for any
> changes since 1.2.1. There were only context changes - bus_space vs. bus_io.
> Does anyone know if this is a known missing feature?
The "ahc" driver doesn't know (or care) what type of device its talking
to. That's be beauty of SCSI :-) Also, if the ISA "ahc" couldn't write
to tapes, it would be a problem for the EISA and PCI "ahc" drivers, too,
since it's really all the same driver.
> I can READ from tapes, just can't write!
I suspect it's an artifact of not using the "raw" tape. Try using /dev/rst0.
The block device interface to tapes hasn't really ever worked (the semantics
of implementing it are just too hairy, for one), and probably ought to just
Jason R. Thorpe email@example.com
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