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 610FCC4360C for ; Thu, 26 Sep 2019 15:30:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3E1B5222C6 for ; Thu, 26 Sep 2019 15:30:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727308AbfIZP37 (ORCPT ); Thu, 26 Sep 2019 11:29:59 -0400 Received: from mail-pf1-f196.google.com ([209.85.210.196]:41188 "EHLO mail-pf1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726845AbfIZP37 (ORCPT ); Thu, 26 Sep 2019 11:29:59 -0400 Received: by mail-pf1-f196.google.com with SMTP id q7so2034706pfh.8; Thu, 26 Sep 2019 08:29:57 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=3136Hn68PJl1UpcDcWTT6DU//8E+QjLu7I91jxB67dU=; b=rX7ZDLmZmrMkwPtxyl5upRUcGjtRTd8kTBOkA8O6tHB3ULvU/h2uAHff7ZnbpH8OhR vAORLMsAhvTQx1fUCCt6GQq7+NO0Y08+7QjfUv6vBq3jVh3uN/Aozb/TSk/tAGsC8iDO /eWPFDXvwNunh8KN7+d1C/o5ZcnIeu09+/nBOd/2+rAdnJrbT3WGo6PVw1ydMkvSJYLY SOgL954z9tavBJqIu+d/IsL5NVgubza+JPU/g+Rtvebjs4uvryA8axa6F94utNiCGWLf DemCjQ2+Ne6PoCERIG0arp48tmnHPthPDMKAc07DiS3+Z9fOPFp9voJ+wdkoGPuT8nMU v9GA== X-Gm-Message-State: APjAAAXZAWCRbvPJ2Pc/4ZOsaCOhT0F+3JK9i1LgI9CFohCdUPMQh8x5 IUwecaCVXy4Cli9c9ogeuds= X-Google-Smtp-Source: APXvYqy9+qQi5bwY4W/rhILB3fkfVIfYWOMEGqFaDEWnUg1W0QCEPTY7XWOXcRhT35COF/ha0cKVFQ== X-Received: by 2002:a17:90a:210b:: with SMTP id a11mr4080391pje.23.1569511797498; Thu, 26 Sep 2019 08:29:57 -0700 (PDT) Received: from desktop-bart.svl.corp.google.com ([2620:15c:2cd:202:4308:52a3:24b6:2c60]) by smtp.gmail.com with ESMTPSA id t68sm6450954pgt.61.2019.09.26.08.29.54 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 26 Sep 2019 08:29:56 -0700 (PDT) Subject: Re: [PATCH v4 21/25] ibnbd: server: functionality for IO submission to file or block dev To: Danil Kipnis Cc: Jinpu Wang , Jack Wang , linux-block@vger.kernel.org, linux-rdma@vger.kernel.org, Jens Axboe , Christoph Hellwig , Sagi Grimberg , Jason Gunthorpe , Doug Ledford , rpenyaev@suse.de References: <20190620150337.7847-1-jinpuwang@gmail.com> <20190620150337.7847-22-jinpuwang@gmail.com> From: Bart Van Assche Message-ID: <40f69402-5f38-c78b-8922-3a77babb4c6c@acm.org> Date: Thu, 26 Sep 2019 08:29:53 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 9/26/19 8:25 AM, Danil Kipnis wrote: > On Thu, Sep 26, 2019 at 5:11 PM Bart Van Assche wrote: >>>> This looks really weird. Why to call ibnbd_dev_blk_open() first for file >>>> I/O mode? Why to set dev->blk_open_flags to FMODE_READ in file I/O mode? > > Bart, would it in your opinion be OK to drop the file_io support in > IBNBD entirely? We implemented this feature in the beginning of the > project to see whether it could be beneficial in some use cases, but > never actually found any. I think that's reasonable since the loop driver can be used to convert a file into a block device. Bart.