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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 79158C43334 for ; Tue, 5 Jul 2022 08:38:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=U7BbGBqamk4i1RxeMC2zuBrRdmDZ/kxIUbhAwTpJ0Pg=; b=c3Wr7XtsEPywryM2IN8R+t3ts/ uvtoJbBz49ds7Li+Gbck9czNUVAwqDplAwxzV0kgGcnpmlX665wA+VR24V22/I26RmeCSzeBgIsKt WGhcjGtT4NyhPSF/UZKVOxw09r8X4FVKtJLMk3b5XtiTFLpDIFxUNy3dNpC/VAtPp0VTQVnIxIpUE P7ngWNa3ERz86lasBWD8J6aNSVtkCX68VH3+Mw8cQ3nLtlAw8Gf7iUCMhu9QUvZL9yTppQRwx+fL+ enpUimbpnQ2oyRCIgLkfMaMiQ85yzaZtb1w0QmHyR+4DM/s98cbAOuJ8aa7pGWoAoMq8GwelQBVAY 0TL6qfwg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1o8e4r-00GGTo-TS; Tue, 05 Jul 2022 08:38:37 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1o8e0j-00GEWl-Cj for linux-nvme@lists.infradead.org; Tue, 05 Jul 2022 08:34:22 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 521C168AA6; Tue, 5 Jul 2022 10:34:16 +0200 (CEST) Date: Tue, 5 Jul 2022 10:34:16 +0200 From: Christoph Hellwig To: Chaitanya Kulkarni Cc: linux-block@vger.kernel.org, linux-raid@vger.kernel.org, linux-nvme@lists.infradead.org, linux-fsdevel@vger.kernel.org, axboe@kernel.dk, agk@redhat.com, song@kernel.org, djwong@kernel.org, kbusch@kernel.org, hch@lst.de, sagi@grimberg.me, jejb@linux.ibm.com, martin.petersen@oracle.com, viro@zeniv.linux.org.uk, javier@javigon.com, johannes.thumshirn@wdc.com, bvanassche@acm.org, dongli.zhang@oracle.com, ming.lei@redhat.com, willy@infradead.org, jefflexu@linux.alibaba.com, josef@toxicpanda.com, clm@fb.com, dsterba@suse.com, jack@suse.com, tytso@mit.edu, adilger.kernel@dilger.ca, jlayton@kernel.org, idryomov@gmail.com, danil.kipnis@cloud.ionos.com, ebiggers@google.com, jinpu.wang@cloud.ionos.com Subject: Re: [PATCH 1/6] block: add support for REQ_OP_VERIFY Message-ID: <20220705083416.GA19123@lst.de> References: <20220630091406.19624-1-kch@nvidia.com> <20220630091406.19624-2-kch@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220630091406.19624-2-kch@nvidia.com> User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220705_013421_640898_67C1201B X-CRM114-Status: GOOD ( 15.68 ) X-Mailman-Approved-At: Tue, 05 Jul 2022 01:38:36 -0700 X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Thu, Jun 30, 2022 at 02:14:01AM -0700, Chaitanya Kulkarni wrote: > This adds a new block layer operation to offload verifying a range of > LBAs. This support is needed in order to provide file systems and > fabrics, kernel components to offload LBA verification when it is > supported by the hardware controller. In case hardware offloading is > not supported then we provide API to emulate the same. The prominent > example of that is SCSI and NVMe Verify command. We also provide > an emulation of the same operation that can be used in case H/W does > not support verify. This is still useful when block device is remotely > attached e.g. using NVMeOF. What is the point of providing the offload?