From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756264Ab0EGJzk (ORCPT ); Fri, 7 May 2010 05:55:40 -0400 Received: from mail2.shareable.org ([80.68.89.115]:53809 "EHLO mail2.shareable.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755670Ab0EGJzi (ORCPT ); Fri, 7 May 2010 05:55:38 -0400 Date: Fri, 7 May 2010 10:55:37 +0100 From: Jamie Lokier To: Josef Bacik Cc: linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 3/3] Btrfs: add basic DIO read support Message-ID: <20100507095537.GD19699@shareable.org> References: <20100506190101.GD13974@dhcp231-156.rdu.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100506190101.GD13974@dhcp231-156.rdu.redhat.com> User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Josef Bacik wrote: > 3) Lock the entire range during DIO. I originally had it so we would lock the > extents as get_block was called, and then unlock them as the endio function was > called, which worked great, but if we ever had an error in the submit_io hook, > we could have locked an extent that would never be submitted for IO, so we > wouldn't be able to unlock it, so this solution fixed that problem and made it a > bit cleaner. Does this prevent concurrent DIOs to overlapping or nearby ranges? Thanks, -- Jamie