From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Wilcox Subject: Re: TRIM vs UNMAP vs WRITE SAME and thin devices Date: Sat, 7 Feb 2009 15:47:22 -0700 Message-ID: <20090207224722.GA31509@parisc-linux.org> References: <20090123041558.GC24652@parisc-linux.org> <4979AF62.7070409@redhat.com> <1232721777.4430.7.camel@macbook.infradead.org> <498DA052.6090605@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: David Woodhouse , James Bottomley , "Martin K. Petersen" , Jeff Garzik , linux-scsi@vger.kernel.org, linux-fsdevel@vger.kernel.org, IDE/ATA development list To: Ric Wheeler Return-path: Content-Disposition: inline In-Reply-To: <498DA052.6090605@redhat.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Sat, Feb 07, 2009 at 09:53:06AM -0500, Ric Wheeler wrote: > I have been poked at by some vendors about the status of our support for > the virtually/thinly provisioned luns since they are getting close to > being able to test with real devices. > > My quick summary is that we most of the work so far has been done > without any real hardware to play with - in 2.6.29-rc3, I don't see any > low level ATA or SCSI bits that turn requests tagged with REQ_DISCARD > into the specific ATA or SCSI commands. Did I miss something & if not, > do we have plans to push anything upstream soonish? Bearing in mind that I'm now three weeks behind on email, you might want to look at http://git.kernel.org/?p=linux/kernel/git/willy/ssd.git;a=shortlog;h=trim-20081231 which has at least one known bug (fixed by Dave Woodhouse and Ben Herrenschmidt). I'll be able to give a more coherent answer in a few days. Or maybe Dave will beat me to it ;-) -- Matthew Wilcox Intel Open Source Technology Centre "Bill, look, we understand that you're interested in selling us this operating system, but compare it to ours. We can't possibly take such a retrograde step."