From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8FDA4C433F5 for ; Fri, 20 May 2022 03:47:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345200AbiETDrP (ORCPT ); Thu, 19 May 2022 23:47:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48710 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345199AbiETDrM (ORCPT ); Thu, 19 May 2022 23:47:12 -0400 Received: from esa2.hgst.iphmx.com (esa2.hgst.iphmx.com [68.232.143.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 55A0630543 for ; Thu, 19 May 2022 20:47:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=wdc.com; i=@wdc.com; q=dns/txt; s=dkim.wdc.com; t=1653018430; x=1684554430; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=6lc1EXDyRH/qdIBQrgfdid5K6UO5RT0eqtEDiI6MCtI=; b=b1V610WnM6PI9vkwIr9SXIPDEAlmxIzBJcxjChVsZy+TGTvq4wSwjljf muGlWVCwOCBusSaLxcM4F5DgRGpYe908tfnbKqUzZSWpes6lml3c1ObrH 6CVr7CV9Zm1HVjnv3Z9QHQPRt36wLh9oHpJCWenqeAxer2HFhqCl82z3y 335Rr3unxQJHPq9I2cm6BosSP/hDVHCIJYAmvC6Xemg1lUJDXQLEfTfVm S7hmlZQJXgcSveviX20PHee5/F1CVLU9upRE6fl5/ieLP+dDM1v7mXsUj ishMPvp5B8c3jjmZ82M5qRw6PuNk7/0j/GqYpYe6E/LG7vneEUZQ6ZnXq A==; X-IronPort-AV: E=Sophos;i="5.91,238,1647273600"; d="scan'208";a="305089249" Received: from uls-op-cesaip01.wdc.com (HELO uls-op-cesaep01.wdc.com) ([199.255.45.14]) by ob1.hgst.iphmx.com with ESMTP; 20 May 2022 11:47:08 +0800 IronPort-SDR: VV/kQBbMCkn10PT6L4nlhOgyMReIDdW4dxSC9L7ZfKRkG9QKnPf/BbJFSv24155V23nY3kad1X lHCx3umiPPKi6Z655J0AxWr+UG/cG+JbmRnfQF/lh2uICltz9hPNU5do8OU83MypRvJdHsniUR Bl2onS0g5AEBJRG058DDLiHdXkUIWTcFlDRyN0Nx4Yg2AYZO63vQp4/kM3b0qG7rJ4pCCI1Cy+ EDOHo2X1thtQcCw6FO0O1PFbCIc7WYvMu8RaSrRai1Z2mzkgjR5HBi1mB1oPHVayTkEajjn8G2 tZFiyyRUH1qa9pjx/KC4QkUa Received: from uls-op-cesaip02.wdc.com ([10.248.3.37]) by uls-op-cesaep01.wdc.com with ESMTP/TLS/ECDHE-RSA-AES128-GCM-SHA256; 19 May 2022 20:12:32 -0700 IronPort-SDR: lgP++SubnHr/6Zx0yCaI8Cw9iZetknnEcUOMe6tRdim/I8r45qSWLkP4AOwJHZnILwp9HAwb5E VDPIz9TpUEGmTslXYFPQb00uK0YbKJWHvFtk/74fEkF9uZEhZ2SF4rtH3pWEsnP1hiNgsfV7BS LkrDwCMFhriDdvMKPZuqXqPLl/DVcOxsyMdOz/si0vABUFf4TdyuHV5uEozJILxg2tSYnbniD9 IozaOzI9AsRdwt6G+FAsKz4Jynbfx7WvBtxSup3mwzt6cHnlR5yWcHGeUBZHsSZ0LJcjOCbXPk 02A= WDCIronportException: Internal Received: from usg-ed-osssrv.wdc.com ([10.3.10.180]) by uls-op-cesaip02.wdc.com with ESMTP/TLS/ECDHE-RSA-AES128-GCM-SHA256; 19 May 2022 20:47:09 -0700 Received: from usg-ed-osssrv.wdc.com (usg-ed-osssrv.wdc.com [127.0.0.1]) by usg-ed-osssrv.wdc.com (Postfix) with ESMTP id 4L4CMw4JcRz1SVp3 for ; Thu, 19 May 2022 20:47:08 -0700 (PDT) Authentication-Results: usg-ed-osssrv.wdc.com (amavisd-new); dkim=pass reason="pass (just generated, assumed good)" header.d=opensource.wdc.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d= opensource.wdc.com; h=content-transfer-encoding:content-type :in-reply-to:organization:from:references:to:content-language :subject:user-agent:mime-version:date:message-id; s=dkim; t= 1653018427; x=1655610428; bh=6lc1EXDyRH/qdIBQrgfdid5K6UO5RT0eqtE DiI6MCtI=; b=Qs9M+NujlyY8B4k/o4j7hSbfG13ti0oADtMb/umY3xRCYTQNY3J T2xdFmUh9CSB7RfRlgugV018loJtAR0z9EGT0S58D6UYUFDTmHf8P8VRWqemnD12 hS5OmTUPjVTzO+ZX5W6IdWB0kk6jh2k0nN3xK9Z0v3wpoOMnabK1LKBbkgGTqBxf z7r3LFquTotFb5ib6u0lxv3Tw3J3qHygfRYrez3CbkQ5MZOQjEIeRlWkIKwHWt+R TYFK2ggtvkfb8RaQH6RyquQyFCRfVmNQe16t3cZb3xRBq3AUFjgPefGP0/pWMal0 Ic2RxZWrwEWckGJNSitECSJ/V7Iv8+V+Fqg== X-Virus-Scanned: amavisd-new at usg-ed-osssrv.wdc.com Received: from usg-ed-osssrv.wdc.com ([127.0.0.1]) by usg-ed-osssrv.wdc.com (usg-ed-osssrv.wdc.com [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id toMqm-8IwTVC for ; Thu, 19 May 2022 20:47:07 -0700 (PDT) Received: from [10.225.163.45] (unknown [10.225.163.45]) by usg-ed-osssrv.wdc.com (Postfix) with ESMTPSA id 4L4CMr5cBWz1Rvlc; Thu, 19 May 2022 20:47:04 -0700 (PDT) Message-ID: <4a8f0e1b-0acb-1ed4-8d7a-c9ba93fcfd02@opensource.wdc.com> Date: Fri, 20 May 2022 12:47:03 +0900 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.9.0 Subject: Re: [dm-devel] [PATCH v4 00/13] support non power of 2 zoned devices Content-Language: en-US To: Johannes Thumshirn , Luis Chamberlain Cc: Theodore Ts'o , Christoph Hellwig , Pankaj Raghav , "axboe@kernel.dk" , "pankydev8@gmail.com" , "gost.dev@samsung.com" , "jiangbo.365@bytedance.com" , "linux-nvme@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "linux-block@vger.kernel.org" , "linux-fsdevel@vger.kernel.org" , "dm-devel@redhat.com" , "dsterba@suse.com" , "linux-btrfs@vger.kernel.org" References: <20220516165416.171196-1-p.raghav@samsung.com> <20220517081048.GA13947@lst.de> <7f9cb19b-621b-75ea-7273-2d2769237851@opensource.wdc.com> <20220519031237.sw45lvzrydrm7fpb@garbanzo> <69f06f90-d31b-620b-9009-188d1d641562@opensource.wdc.com> From: Damien Le Moal Organization: Western Digital Research In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 5/19/22 16:34, Johannes Thumshirn wrote: > On 19/05/2022 05:19, Damien Le Moal wrote: >> On 5/19/22 12:12, Luis Chamberlain wrote: >>> On Thu, May 19, 2022 at 12:08:26PM +0900, Damien Le Moal wrote: >>>> On 5/18/22 00:34, Theodore Ts'o wrote: >>>>> On Tue, May 17, 2022 at 10:10:48AM +0200, Christoph Hellwig wrote: >>>>>> I'm a little surprised about all this activity. >>>>>> >>>>>> I though the conclusion at LSF/MM was that for Linux itself there >>>>>> is very little benefit in supporting this scheme. It will massively >>>>>> fragment the supported based of devices and applications, while only >>>>>> having the benefit of supporting some Samsung legacy devices. >>>>> >>>>> FWIW, >>>>> >>>>> That wasn't my impression from that LSF/MM session, but once the >>>>> videos become available, folks can decide for themselves. >>>> >>>> There was no real discussion about zone size constraint on the zone >>>> storage BoF. Many discussions happened in the hallway track though. >>> >>> Right so no direct clear blockers mentioned at all during the BoF. >> >> Nor any clear OK. > > So what about creating a device-mapper target, that's taking npo2 drives and > makes them po2 drives for the FS layers? It will be very similar code to > dm-linear. +1 This will simplify the support for FSes, at least for the initial drop (if accepted). And more importantly, this will also allow addressing any potential problem with user space breaking because of the non power of 2 zone size. > > After all zoned support for FSes started with a device-mapper (dm-zoned) and > as the need for a more integrated solution arose, it changed into natiive > support. > > And all that is there is simple arithmetic and a bio_clone(), if this is the > slowest part of the stack involving a FS like f2fs or btrfs I'm throwing a > round of anyone's favorite beverage at next year's LSFMM. > > Byte, > Johannes > -- Damien Le Moal Western Digital Research