From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Bottomley Subject: Re: [PATCH] ieee1394: sbp2: lower block queue alignment requirement Date: Sun, 14 Jan 2007 13:19:47 -0600 Message-ID: <1168802387.2780.1.camel@mulgrave.il.steeleye.com> References: Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: Received: from hancock.steeleye.com ([71.30.118.248]:33896 "EHLO hancock.sc.steeleye.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751631AbXANTT6 (ORCPT ); Sun, 14 Jan 2007 14:19:58 -0500 In-Reply-To: Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Stefan Richter Cc: linux1394-devel@lists.sourceforge.net, linux-scsi@vger.kernel.org On Sun, 2007-01-14 at 19:45 +0100, Stefan Richter wrote: > I wonder, do we need this call to blk_queue_dma_alignment() at all? > Does the block layer perhaps provide sufficient alignment guarantees? The block layer currently provides sector (512) byte alignment guarantees. However, there has been talk in SCSI of reducing that to word (4) since that's what most intelligent PCI controllers can cope with. If you have any alignment constraints, they should be expressed in the slave configure. James