From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Subject: Re: [PATCH 0/2] MMC discard support (was [PATCH 0/7] Discard requests, v2) Date: Fri, 22 Aug 2008 12:50:40 +0200 Message-ID: <20080822105039.GG20055@kernel.dk> References: <1218299181.26926.88.camel@pmac.infradead.org> <20080816190858.4d150ea1@mjolnir.drzeus.cx> <20080822092448.GC20055@kernel.dk> <1219398302.9583.21.camel@pmac.infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Pierre Ossman , linux-fsdevel@vger.kernel.org To: David Woodhouse Return-path: Received: from [93.163.65.50] ([93.163.65.50]:18543 "EHLO kernel.dk" rhost-flags-FAIL-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1753288AbYHVKun (ORCPT ); Fri, 22 Aug 2008 06:50:43 -0400 Content-Disposition: inline In-Reply-To: <1219398302.9583.21.camel@pmac.infradead.org> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Fri, Aug 22 2008, David Woodhouse wrote: > On Fri, 2008-08-22 at 11:24 +0200, Jens Axboe wrote: > > I agree with that, the thought did cross my mind earlier as well. I > > committed something like the below (in two patches). > > But there _are_ limits on how many sectors can be discarded in a single > operation. For ATA 'Trim' I think it's 65536? Do we want to force the > drivers to translate a single request into multiple actual commands? Hmm right, I guess the sector limit in the command of course still applies. > I suspect we need a separate 'max_discard_sectors' field. No, that is what max_hw_sectors is for. -- Jens Axboe