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=-2.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, 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 77AF0C433DF for ; Thu, 21 May 2020 14:21:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 47B5920748 for ; Thu, 21 May 2020 14:21:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=kernel-dk.20150623.gappssmtp.com header.i=@kernel-dk.20150623.gappssmtp.com header.b="IubiXOXx" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728077AbgEUOVH (ORCPT ); Thu, 21 May 2020 10:21:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53472 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727985AbgEUOVH (ORCPT ); Thu, 21 May 2020 10:21:07 -0400 Received: from mail-pj1-x1042.google.com (mail-pj1-x1042.google.com [IPv6:2607:f8b0:4864:20::1042]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 071E5C061A0E for ; Thu, 21 May 2020 07:21:05 -0700 (PDT) Received: by mail-pj1-x1042.google.com with SMTP id s69so3134012pjb.4 for ; Thu, 21 May 2020 07:21:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20150623.gappssmtp.com; s=20150623; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=tqWT/aJMqjQS/LwwIzDw5vVtbTuX7+bbQKCciE383sc=; b=IubiXOXxF2nL7YfH5AF2oZumoIioFJkh2cyMRIZp0jsTtdJTU6sm5tTkN3HB9KSqpr BtfBrkxRHj9emgX0ItTzLqrFslEgmDV5pO1oagyiFOJUdNGqmgdWCpF92vGx8KmQIdr8 FTDpUs3OaOO5TVWe6ABfw+7ANd0xGdrP5T9kYTlX81C50wZB5HxY+ZNlwgC4QnTvB4YM i1IqzwpR0hiihyC8n83UH2C42t418sA/KbyBT2urJw8cwaWySpd+n+xOxbR6Lzi9J9IL K8VxDTfFDp42DN/+XuQKeLell9ggOV648PoVukEpAqYDM5Peiu2huxXaw3PifSu6hRYg TaIg== 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=tqWT/aJMqjQS/LwwIzDw5vVtbTuX7+bbQKCciE383sc=; b=iqyAAkinSX5UNUwdkK8Mp7SDiQgGMfnn6QT5c5rCSxQGb5W+gc2vFvu1wyzR5lGAEH Cej6pIERsXwmA8EbEN7Du4Oi5x2WTSrLfM91H3d9/sAXgqCeyxtQGtN0c7D1X50c4mIc ROMHOOv6iyRSBu9ThdPk4xQJFszTW7kG5SRz6aQ1BhxawzmCQWMMUrAx0jsDk/CshuBL 21Zys9ptOQgJAlF6yja8nDJTo6XqAlOyEQ3CBormB+06DiuU1kf1WQXoa4kXv1w2zG5X 7MjDSbJFgDRqIvsMujgLHgauRPq5oQFwULPkETkFGdim7uNDXAP3cdQX/zduQcgHTxID HCdg== X-Gm-Message-State: AOAM532I860qldVV3SpWIZye7QpOOmvzagW2V+SkleG3BRLmhoCYrqWp fSmbY4EFM68GmZ33Mxy/SV9lMA== X-Google-Smtp-Source: ABdhPJwJWiF05G52IFW9R5Nmw5veE7Mlw/Rui0UPeykYh3HiKu3fnjOBS9uNDK1RBAVTK+i14VNZqg== X-Received: by 2002:a17:902:7047:: with SMTP id h7mr10219648plt.9.1590070864321; Thu, 21 May 2020 07:21:04 -0700 (PDT) Received: from ?IPv6:2605:e000:100e:8c61:c00a:8fd2:4246:efbe? ([2605:e000:100e:8c61:c00a:8fd2:4246:efbe]) by smtp.gmail.com with ESMTPSA id k65sm4703876pfd.156.2020.05.21.07.21.02 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 21 May 2020 07:21:03 -0700 (PDT) Subject: Re: [PATCH v5 00/11] Add a new LOOP_CONFIGURE ioctl To: Martijn Coenen , hch@lst.de, ming.lei@redhat.com Cc: narayan@google.com, zezeozue@google.com, maco@google.com, kernel-team@android.com, bvanassche@acm.org, Chaitanya.Kulkarni@wdc.com, jaegeuk@kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org References: <20200513133845.244903-1-maco@android.com> From: Jens Axboe Message-ID: Date: Thu, 21 May 2020 08:21:01 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: <20200513133845.244903-1-maco@android.com> Content-Type: text/plain; charset=utf-8 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 5/13/20 7:38 AM, Martijn Coenen wrote: > This series introduces a new ioctl that makes it possible to atomically > configure a loop device. Previously, if you wanted to set parameters > such as the offset on a loop device, this required calling LOOP_SET_FD > to set the backing file, and then LOOP_SET_STATUS to set the offset. > However, in between these two calls, the loop device is available and > would accept requests, which is generally not desirable. Similar issues > exist around setting the block size (LOOP_SET_BLOCK_SIZE) and requesting > direct I/O mode (LOOP_SET_DIRECT_IO). > > There are also performance benefits with combining these ioctls into > one, which are described in more detail in the last change in the > series. Thanks, applied for 5.8. -- Jens Axboe