From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756353AbZEUCI7 (ORCPT ); Wed, 20 May 2009 22:08:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754209AbZEUCIw (ORCPT ); Wed, 20 May 2009 22:08:52 -0400 Received: from n9.bullet.mail.mud.yahoo.com ([209.191.86.157]:28402 "HELO n9.bullet.mail.mud.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1753814AbZEUCIv (ORCPT ); Wed, 20 May 2009 22:08:51 -0400 X-Greylist: delayed 360 seconds by postgrey-1.27 at vger.kernel.org; Wed, 20 May 2009 22:08:51 EDT X-Yahoo-Newman-Id: 384892.28731.bm@omp401.mail.mud.yahoo.com DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=pacbell.net; h=Received:X-YMail-OSG:X-Yahoo-Newman-Property:From:To:Subject:Date:User-Agent:Cc:References:In-Reply-To:MIME-Version:Content-Type:Content-Transfer-Encoding:Content-Disposition:Message-Id; b=GiVkGpkmpS9EbH1R7uc8IB+zqWkRPsz2249gKzVqtVB82/TtvvoHc8RsaVQr/dG99dn8xliL8q2r4toLzjCuG/O6b94ThH3IkrGtlFJgRHBwVyOQnahB4dLzQdGXBEbDcSuPmWN9YZ8NN1nc6CNniMLznQhGApNydStj2nGpDlY= ; X-YMail-OSG: 3Ew7lVoVM1mIJQgIg7jMOKEtyUBkNRlR5bFjVwoE4w2O.H_rXvjJy7Umo9KFS40gpvt46j4wl8chHi09VtGVO.ZVXrwcyZKhpUwEWb.FRHsG5sb2tD4dEx86.ilGjsMAXhKk3MPCavWzHTQvJntWOL_HpRjbRcnBlgYZlmJJL5PZtKrTUlFnT8ZnKkq.KKhgZFj2l3UH0DXMFFAwqM1ggAkZVw-- X-Yahoo-Newman-Property: ymail-3 From: David Brownell To: Pierre Ossman Subject: Re: [PATCH] mmc_spi: use EILSEQ for possible transmission errors Date: Wed, 20 May 2009 19:02:51 -0700 User-Agent: KMail/1.9.10 Cc: Wolfgang =?iso-8859-1?q?M=FCes?= , "Matt Fleming" , "Pierre Ossman" , "Andrew Morton" , "Mike Frysinger" , linux-kernel@vger.kernel.org References: <200905192149.07778.david-b@pacbell.net> <200905200220.46569.david-b@pacbell.net> <20090520120851.49783a8e@mjolnir.ossman.eu> In-Reply-To: <20090520120851.49783a8e@mjolnir.ossman.eu> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit Content-Disposition: inline Message-Id: <200905201902.51377.david-b@pacbell.net> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wednesday 20 May 2009, Pierre Ossman wrote: > > Remember that the > > firmware in the card can leverage "that's erased" knowledge for > > things like wear leveling.  SSDs and other storage devices would > > likewise benefit from such knowledge.  I'm quite certain there's > > been discussion about adding support for that in the block layer. > > It's already in AFAIK. I even had code for hooking it up to mmc_block. > But it didn't produce any measurable results so I never merged it. I'd expect the results would take time to show. As in, they would facilitate wear leveling logic, which may be difficult to measure except by testing various cards to destruction ... even for vendors that *do* have decent wear leveling. :)