[138] in linux-scsi channel archive
BusLogic/HP-DAT Problems - Solved
daemon@ATHENA.MIT.EDU (Leonard N. Zubkoff)
Mon Apr 10 13:53:12 1995
Date: Mon, 10 Apr 1995 09:34:37 -0700
From: "Leonard N. Zubkoff" <lnz@dandelion.com>
To: eowmob@exp-math.uni-essen.de
Cc: linux-scsi@vger.rutgers.edu
In-Reply-To: Michael Weller's message of Mon, 10 Apr 1995 12:48:39 +0200 (MSZ) <Pine.3.89.9504101229.B29610-0100000@werner.exp-math.uni-essen.de>
Date: Mon, 10 Apr 1995 12:48:39 +0200 (MSZ)
From: Michael Weller <eowmob@exp-math.uni-essen.de>
IMHO in general underruns are no errors, esp. for tapes.., things are
different in some situations (like this) or for disks, for example.
However the low-level driver can't know this. So it should not report
a fatal error and give the mid-level driver a chance to check for underruns
itself instead.
I think this condition can not occur when using variable block sizes..
but making the Buslogic driver support only variable block size tapes sounds
not like a good idea to me.
I can only assume from the above comments that you've not completely understood
the effect and purpose of my patch. An underrun with respect to the byte count
or block count provided in the SCSI CDB is still handled just as it always was.
The only change my patch makes is to correctly tell the driver what the maximum
byte count you've given the device actually is. This patch should have no
effect whatsoever on cases that worked before as the device should *never* have
provided more data than allowed for in the CDB anyway. This really is an
inconsistency in the existing code, rather than a change in how things work.
Leonard
