From owner-freebsd-scsi Thu Dec 2 10:35:21 1999 Delivered-To: freebsd-scsi@freebsd.org Received: from panzer.kdm.org (panzer.kdm.org [216.160.178.169]) by hub.freebsd.org (Postfix) with ESMTP id A909314DA5 for ; Thu, 2 Dec 1999 10:35:14 -0800 (PST) (envelope-from ken@panzer.kdm.org) Received: (from ken@localhost) by panzer.kdm.org (8.9.3/8.9.1) id LAA50772; Thu, 2 Dec 1999 11:34:45 -0700 (MST) (envelope-from ken) Message-Id: <199912021834.LAA50772@panzer.kdm.org> Subject: Re: Tape driver problems In-Reply-To: from Matthew Jacob at "Dec 2, 1999 10:20:19 am" To: mjacob@feral.com Date: Thu, 2 Dec 1999 11:34:45 -0700 (MST) Cc: syssgm@detir.qld.gov.au (Stephen McKay), freebsd-scsi@FreeBSD.ORG From: "Kenneth D. Merry" X-Mailer: ELM [version 2.4ME+ PL54 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-scsi@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org Matthew Jacob wrote... > > > > > This is an "old" problem, ie more than 2 weeks, at least. :-) > > > > > > > > "mt status" with a tape loaded gives the correct values (including density), > > > > but the kernel spits out: > > > > > > > > Dec 3 00:44:36 bucket /kernel: bus_dmamap_load: Too many segs! buf_len = 0x3000 > > > > > > > > The last bit changes. I've seen 0xb000 or 0xd000 or 0xe000 or 0xf000 also. > > > > This is a new problem related to the density autodetection read. I expect > > > > that an aha1542B just can't read MAXPHYS bytes from anything. > > > > > > Hmm, indeed. The density determining code does indeed issue a read of > > > MAXPHYS bytes. It seems to me that all HBA's should at least support that! > > > The maintainer for the 1542X will have to speak to this tho... > > > > I'm not the aha maintainer (Warner is), but I do know that it cannot do > > I didn't say you were. I know you didn't. But if I didn't make that qualification, from previous experience I can guess that I would get mail from a few people complaining about some problem they have with their aha board. I was just trying to take some preventative action. > > more than 64K at a time. So you shouldn't be using any more than that. > > Nonsense. That's what bounce buffers can or *should* be used for too. Well, talk to Warner about it. You could probably use bounce buffers to handle the problem. For now, though, I think 64K is the lowest common denominator. Ken -- Kenneth Merry ken@kdm.org To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-scsi" in the body of the message