From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 27 Aug 2002 12:10:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 27 Aug 2002 12:10:25 -0400 Received: from smtp02.uc3m.es ([163.117.136.122]:19467 "HELO smtp.uc3m.es") by vger.kernel.org with SMTP id ; Tue, 27 Aug 2002 12:10:25 -0400 From: "Peter T. Breuer" Message-Id: <200208271614.g7RGEhe27614@oboe.it.uc3m.es> Subject: Re: block device/VM question In-Reply-To: from Thunder from the hill at "Aug 27, 2002 10:06:50 am" To: Thunder from the hill Date: Tue, 27 Aug 2002 18:14:43 +0200 (MET DST) Cc: linux kernel X-Anonymously-To: Reply-To: ptb@it.uc3m.es X-Mailer: ELM [version 2.4ME+ PL66 (25)] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org "A month of sundays ago Thunder from the hill wrote:" > Hi, > On Tue, 27 Aug 2002, Peter T. Breuer wrote: > > Is there any way of turning off VMS caching for a block device? > O_DIRECT, or easily set the buffer to zero... Thanks! Yes, I've noticed this in the 2.5.31 kernel. This is something to be done on open by the overlying fs or userspace utility, or should I set the flag on the inode->filp (or whatever) myself in the drivers open function? And do I need to define inode->mapping->a_ops->direct_IO()? (sorry - but I haven't had time to experiment yet today!). It looks like the 2.5 kernel has this pathway, but what about the 2.4 kernel? Nothing. Peter