From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759024Ab0EMPXR (ORCPT ); Thu, 13 May 2010 11:23:17 -0400 Received: from mx1.redhat.com ([209.132.183.28]:15026 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753784Ab0EMPXP (ORCPT ); Thu, 13 May 2010 11:23:15 -0400 Date: Thu, 13 May 2010 11:31:45 -0400 From: Josef Bacik To: Christoph Hellwig Cc: Josef Bacik , linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, akpm@linux-foundation.org Subject: Re: [PATCH 4/4] Btrfs: add basic DIO read/write support V3 Message-ID: <20100513153145.GE27011@dhcp231-156.rdu.redhat.com> References: <20100512204052.GD3597@localhost.localdomain> <20100513151429.GA16916@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100513151429.GA16916@infradead.org> User-Agent: Mutt/1.5.19 (2009-01-05) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 13, 2010 at 11:14:30AM -0400, Christoph Hellwig wrote: > On Wed, May 12, 2010 at 04:40:53PM -0400, Josef Bacik wrote: > > V1->V2 > > -Use __blockdev_direct_IO instead of helper > > -Use KM_IRQ0 for kmap instead of KM_USER0 > > I still don't think this is correct. The completion can come from > softirq and hardirq context, and possibly even normal process context. > You either need to check for all these, or you need to use the generic > complete in user context helper btrfs has available for other types > of I/O. > AIO's aio_complete does kmap with KM_IRQ0/1 and it gets called in the same context as the btrfs completion handler, so if it's ok for aio_complete it should be ok for btrfs right? Thanks, Josef