From owner-freebsd-bugs Thu Jun 20 14:17:14 1996 Return-Path: owner-bugs Received: (from root@localhost) by freefall.freebsd.org (8.7.5/8.7.3) id OAA09507 for bugs-outgoing; Thu, 20 Jun 1996 14:17:14 -0700 (PDT) Received: from irz301.inf.tu-dresden.de (irz301.inf.tu-dresden.de [141.76.1.11]) by freefall.freebsd.org (8.7.5/8.7.3) with SMTP id OAA09386 for ; Thu, 20 Jun 1996 14:15:44 -0700 (PDT) Received: from sax.sax.de by irz301.inf.tu-dresden.de (8.6.12/8.6.12-s1) with ESMTP id XAA22120; Thu, 20 Jun 1996 23:10:51 +0200 Received: (from uucp@localhost) by sax.sax.de (8.6.12/8.6.12-s1) with UUCP id XAA26710; Thu, 20 Jun 1996 23:10:50 +0200 Received: (from j@localhost) by uriah.heep.sax.de (8.7.5/8.6.9) id UAA17515; Thu, 20 Jun 1996 20:48:02 +0200 (MET DST) From: J Wunsch Message-Id: <199606201848.UAA17515@uriah.heep.sax.de> Subject: Re: bin/1320: dump limits blocksize to 32K To: bde@zeta.org.au (Bruce Evans) Date: Thu, 20 Jun 1996 20:48:02 +0200 (MET DST) Cc: gwk@cray.com, bde@zeta.org.au, freebsd-bugs@freefall.freebsd.org, gpalmer@FreeBSD.org, dyson@FreeBSD.org, davidg@FreeBSD.org (David Greenman) Reply-To: joerg_wunsch@uriah.heep.sax.de (Joerg Wunsch) In-Reply-To: <199606191248.WAA16277@godzilla.zeta.org.au> from Bruce Evans at "Jun 19, 96 10:48:51 pm" X-Phone: +49-351-2012 669 X-PGP-Fingerprint: DC 47 E6 E4 FF A6 E9 8F 93 21 E0 7D F9 12 D6 4E X-Mailer: ELM [version 2.4ME+ PL17 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-bugs@FreeBSD.org X-Loop: FreeBSD.org Precedence: bulk As Bruce Evans wrote: > >It splits the request into 64 KB chunks, so it can handle them. This > >works mostly except for tapes, which are IMHO the only devices that > >might require a physical blocksize larger than 64 KB > > physio() needs to have a no-split flag that would be set by the tape > drivers. I would rather like to see the problem resolved once and for all. This will however require some ``bounce buffer'' support, at least for those controllers that can only handle 16 scatter/gather segments (thus 16 physical pages == 64 KB). David? John? Any opinion about this? -- 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. ;-)