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Date: Sun, 4 Jun 2006 03:05:23 GMT
From: Matt Jacob <mjacob@FreeBSD.org>
Message-Id: <200606040305.k5435Nm3083345@freefall.freebsd.org>
To: scsi@freebsd.org
Cc: 
Subject: changes to cam_xpt to support sequential scanning (!parallel)
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One solution that Scott suggested to some of the negotiation issues for
the MPT was to not do parallel problem, i.e., all targets in parallel.

The patch at http://people.freebsd.org/~mjacob/CAM_PATCHES_FOR_SEQSCAN

does just that and I've had quite good success with it so far. I add
a new flat, PIM_SEQSCAN, which cases xpt_scan_bus to *not* scan all
targets in parallel but rather to scan them sequentially.

Comments?

The code also does some cleanups under failure conditions.

After a bit more testing I'd like to put this in if there are no
objections so I can get the mpt U320 stuff off my back for a while.