From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matias Bjorling Subject: Re: [dm-devel] [PATCH RFC v1 01/01] dm-lightnvm: An open FTL for open firmware SSDs Date: Mon, 24 Mar 2014 20:45:25 -0700 Message-ID: <5330FBD5.5000103@bjorling.me> References: <1395383538-18019-1-git-send-email-m@bjorling.me> <1395383538-18019-2-git-send-email-m@bjorling.me> <20140321153749.GA17155@infradead.org> <532C67D0.4020501@bjorling.me> <20140325112217.a3d34601d745ace3fbc07c0f@valinux.co.jp> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Christoph Hellwig , snitzer@redhat.com, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, agk@redhat.com To: Akira Hayakawa , device-mapper development Return-path: In-Reply-To: <20140325112217.a3d34601d745ace3fbc07c0f@valinux.co.jp> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On 03/24/2014 07:22 PM, Akira Hayakawa wrote: > Hi, Matias, > > Sorry for jumping in. I am interested in this new feature, too. > >>> Does it even make sense to expose the underlying devices as block >>> devices? It surely would help to send this together with a driver >>> that you plan to use it on top of. >>> >> >> Agree, an underlying driver is missing. My first plan is to get a draft >> firmware for the OpenSSD to be stable and expose its primitives >> (read/write/erase) up through the ATA/SCSI stack. Communicating using >> vendor specific codes. > Hi Akira, Indeed. Most of Mohit's work can be applied with this layer. In the same breath we could also look into nameless writes. It would up open for a new design for co-operating file systems. > Exposing FTL to the host layer has potential to share mapping in cache software (or driver) and the device. > The "Unified Address Space" in the slides below addresses the problem of two levels of indirection. > http://www1.unine.ch/eurosys2012/posters/saxena.pdf > > Developing API to share mapping between driver and the device sounds interesting, too. > > -- > Akira > -- > To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >