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 2C121C43334 for ; Tue, 5 Jul 2022 08:38:51 +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=JWB31PmJw69iMcUSkAYBcf6hwHi0oaY3ywspIB5IkiY=; b=r6Bd87Jxvt9UrUqAnsOIb9TvRV S6dQj31qfQ/KckA5NO1GPLeOUVpyH3ehKnEVdCfA3nGI2X1hg8iUCZ48XjwvJrq8ZR+rlT5hRbq9r PeNgDfBKel4C9ATPh6PPOY8ILtWH4kEezLfB7aORCkMSXxNtI1ESGGaRlhLFr9eiV071n2SYdQIsk mi+W/IKx70H4S6nYXu6SRz+IcWDECK16HBeUj+wW0yPVgGmR3hQm8B1UkK8rJzRxDItgJZWSz9g3E 3qI/rPMIlWJ0Zahm+UPFXXGJDRvNQYFg9Yk9WM6cxN2Ylu7EjI5FKBKUJEVvYKIks5v9qrgvGU7ao CxZYL2Iw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1o8e4z-00GGVR-PD; Tue, 05 Jul 2022 08:38:45 +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 1o8e2I-00GFEx-Ec for linux-nvme@lists.infradead.org; Tue, 05 Jul 2022 08:35:59 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 8F68468AA6; Tue, 5 Jul 2022 10:35:55 +0200 (CEST) Date: Tue, 5 Jul 2022 10:35:55 +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 4/6] nvmet: add Verify emulation support for bdev-ns Message-ID: <20220705083555.GC19123@lst.de> References: <20220630091406.19624-1-kch@nvidia.com> <20220630091406.19624-5-kch@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220630091406.19624-5-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_013558_661522_CEB3AAD0 X-CRM114-Status: GOOD ( 13.82 ) 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 02:14:04AM -0700, Chaitanya Kulkarni wrote: > Not all devices can support verify requests which can be mapped to > the controller specific command. This patch adds a way to emulate > REQ_OP_VERIFY for NVMeOF block device namespace. We add a new > workqueue to offload the emulation. How is this an "emulation"? Also why do we need the workqueue offloads? I can't see any good reason to not just simply submit the bio asynchronously like all the other bios submitted by the block device backend.