From mboxrd@z Thu Jan 1 00:00:00 1970 From: J Freyensee Subject: Re: bounce_sg and sg in mmc_queue Date: Thu, 22 Sep 2011 09:35:04 -0700 Message-ID: <4E7B63B8.2000100@linux.intel.com> References: <4E7A2C6E.70408@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mga03.intel.com ([143.182.124.21]:63469 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751781Ab1IVQ3O (ORCPT ); Thu, 22 Sep 2011 12:29:14 -0400 Received: from [10.7.232.151] (poundcake.jf.intel.com [10.7.232.151]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by linux.intel.com (Postfix) with ESMTP id D90016A4087 for ; Thu, 22 Sep 2011 09:29:09 -0700 (PDT) In-Reply-To: <4E7A2C6E.70408@linux.intel.com> Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: linux-mmc@vger.kernel.org On 09/21/2011 11:26 AM, J Freyensee wrote: > Hello: > > Could anyone tell me in struct mmc_queue, what is the difference between > 'struct scatterlist *bounce_sg' and 'struct scatterlist *sg' is? > > I see 'bounce_sg' get used to copy data from/to the buffer upon a host > read/write operation so I assume 'bounce_sg' points to the most recent > data from a host controller read/write operation. > If someone actually knows this, I will send up a patch documenting this in the code. I think some of the mmc code could use a little documentation?? > Thanks for the help. > -- J (James/Jay) Freyensee Storage Technology Group Intel Corporation