From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Garzik Subject: Re: [PATCH] libata: initialize qc->dma_dir to DMA_NONE Date: Fri, 19 Jan 2007 19:19:23 -0500 Message-ID: <45B1600B.4000806@pobox.com> References: <45AD50AD.2040700@linux.vnet.ibm.com> <20070116224115.50d29cf7@localhost.localdomain> <45AD55A4.50208@pobox.com> <1168989094.2789.20.camel@mulgrave.il.steeleye.com> <45AD5D27.8020004@linux.vnet.ibm.com> <45AD60B9.3030501@linux.vnet.ibm.com> <20070117023402.GP10987@htj.dyndns.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from srv5.dvmed.net ([207.36.208.214]:53788 "EHLO mail.dvmed.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964930AbXATAT2 (ORCPT ); Fri, 19 Jan 2007 19:19:28 -0500 In-Reply-To: <20070117023402.GP10987@htj.dyndns.org> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Tejun Heo Cc: Brian King , James Bottomley , Alan , linux-scsi@vger.kernel.org, "linux-ide@vger.kernel.org" Tejun Heo wrote: > libata didn't used to init qc->dma_dir to any specific value on qc > initialization and command translation path didn't set qc->dma_dir if > the command doesn't need data transfer. This made non-data commands > to have random qc->dma_dir. > > This usually doesn't cause problem because LLDs usually check > qc->protocol first and look at qc->dma_dir iff the command needs data > transfer but this doesn't hold for all LLDs. > > It might be worthwhile to rename qc->dma_dir to qc->data_dir as we use > the field to tag data direction for both PIO and DMA protocols. > > This problem has been spotted by James Bottomley. > > Signed-off-by: Tejun Heo > Cc: James Bottomley applied to #upstream-fixes