Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261650AbVCIVTt (ORCPT ); Wed, 9 Mar 2005 16:19:49 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261589AbVCIVTr (ORCPT ); Wed, 9 Mar 2005 16:19:47 -0500 Received: from parcelfarce.linux.theplanet.co.uk ([195.92.249.252]:24301 "EHLO parcelfarce.linux.theplanet.co.uk") by vger.kernel.org with ESMTP id S261552AbVCIVSs (ORCPT ); Wed, 9 Mar 2005 16:18:48 -0500 Date: Wed, 9 Mar 2005 21:18:44 +0000 From: Joel Becker To: Andrew Morton Cc: suparna@in.ibm.com, pbadari@us.ibm.com, daniel@osdl.org, sebastien.dugue@bull.net, linux-aio@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] 2.6.10 - direct-io async short read bug Message-ID: <20050309211844.GC2076@parcelfarce.linux.theplanet.co.uk> Mail-Followup-To: Joel Becker , Andrew Morton , suparna@in.ibm.com, pbadari@us.ibm.com, daniel@osdl.org, sebastien.dugue@bull.net, linux-aio@kvack.org, linux-kernel@vger.kernel.org References: <1110189607.11938.14.camel@frecb000686> <20050307223917.1e800784.akpm@osdl.org> <20050308090946.GA4100@in.ibm.com> <1110302614.24286.61.camel@dyn318077bld.beaverton.ibm.com> <1110309508.24286.74.camel@dyn318077bld.beaverton.ibm.com> <1110324434.6521.23.camel@ibm-c.pdx.osdl.net> <1110326043.24286.134.camel@dyn318077bld.beaverton.ibm.com> <20050309040757.GY27331@ca-server1.us.oracle.com> <20050309152047.GA4588@in.ibm.com> <20050309115348.2b86b765.akpm@osdl.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20050309115348.2b86b765.akpm@osdl.org> User-Agent: Mutt/1.4.1i X-Burt-Line: Trees are cool. X-Red-Smith: Ninety feet between bases is perhaps as close as man has ever come to perfection. Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1088 Lines: 30 On Wed, Mar 09, 2005 at 11:53:48AM -0800, Andrew Morton wrote: > Suparna Bhattacharya wrote: > > If writes/truncates take care of zeroing out the rest of the sector > > on disk, might we still be OK without having to do the bounce buffer > > thing ? > > We can probably rely on the rest of the sector outside i_size being zeroed > anyway. Because if it contains non-zero gunk then the fs already has a > problem, and the user can get at that gunk with an expanding truncate and > mmap() anyway. Actually, yeah, even today we rely on block_prepare_write and friends to handle that trail zeroing. That all happens after the sector has been read from disk. So this should be analogous. Joel -- Life's Little Instruction Book #396 "Never give anyone a fruitcake." http://www.jlbec.org/ jlbec@evilplan.org - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/