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 X-Spam-Level: X-Spam-Status: No, score=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 65CC4C2BA1A for ; Fri, 24 Apr 2020 07:54:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 42EE620704 for ; Fri, 24 Apr 2020 07:54:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726298AbgDXHyH (ORCPT ); Fri, 24 Apr 2020 03:54:07 -0400 Received: from verein.lst.de ([213.95.11.211]:33702 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726056AbgDXHyH (ORCPT ); Fri, 24 Apr 2020 03:54:07 -0400 Received: by verein.lst.de (Postfix, from userid 2407) id C99B568CEE; Fri, 24 Apr 2020 09:54:03 +0200 (CEST) Date: Fri, 24 Apr 2020 09:54:03 +0200 From: Christoph Hellwig To: Max Gurtovoy Cc: Christoph Hellwig , linux-nvme@lists.infradead.org, kbusch@kernel.org, sagi@grimberg.me, martin.petersen@oracle.com, jsmart2021@gmail.com, linux-rdma@vger.kernel.org, idanb@mellanox.com, axboe@kernel.dk, vladimirk@mellanox.com, oren@mellanox.com, shlomin@mellanox.com, israelr@mellanox.com, jgg@mellanox.com Subject: Re: [PATCH 15/17] nvmet: Add metadata support for block devices Message-ID: <20200424075403.GA24906@lst.de> References: <20200327171545.98970-1-maxg@mellanox.com> <20200327171545.98970-17-maxg@mellanox.com> <20200421153339.GF10837@lst.de> <3992e1fd-efad-0679-7817-f004b40cdc76@mellanox.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <3992e1fd-efad-0679-7817-f004b40cdc76@mellanox.com> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Thu, Apr 23, 2020 at 08:25:24PM +0300, Max Gurtovoy wrote: > > On 4/21/2020 6:33 PM, Christoph Hellwig wrote: >> On Fri, Mar 27, 2020 at 08:15:43PM +0300, Max Gurtovoy wrote: >>> - if (!nvmet_check_transfer_len(req, nvmet_rw_data_len(req))) >>> + if (!nvmet_check_transfer_len(req, >>> + nvmet_rw_data_len(req) + req->md_len)) >> Shouldn't we also calculate the actual metadata length on the fly here? > > we calculate it during nvmet_init_req. Indeed. > >> >>> blk_start_plug(&plug); >>> + if (req->use_md) >> Can't we use a non-NULL req->md_sg or non-null req->md_sg_cnt as a >> metadata supported indicator and remove the use_md flag? Maybe wrap >> them in a helper function that also checks for blk integrity support >> using IS_ENABLED and we can skip the stubs as well. > > I'll replace it with: > > static inline bool nvmet_req_has_pi(struct nvmet_req *req) > { >         return req->sq->ctrl->pi_support && nvmet_ns_has_pi(req->ns); > } Actually I think you can simply check for a non-0 md_len, as we always set them at the same time.