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=-0.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS autolearn=ham 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 6EFF5C10F13 for ; Tue, 16 Apr 2019 21:30:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3CFB92075B for ; Tue, 16 Apr 2019 21:30:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=web.de header.i=@web.de header.b="h+FK1dML" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729771AbfDPVa4 (ORCPT ); Tue, 16 Apr 2019 17:30:56 -0400 Received: from mout.web.de ([217.72.192.78]:35427 "EHLO mout.web.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726986AbfDPVaz (ORCPT ); Tue, 16 Apr 2019 17:30:55 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=web.de; s=dbaedf251592; t=1555450252; bh=czUW8TU9BfEC93l5PDH4u0516PkET3OYl375+ABECn0=; h=X-UI-Sender-Class:To:From:Subject:Date; b=h+FK1dMLArCZaZXgrO7xllMetwGauE2zgcw5yikrfoOUZTkZEeAk3Z00MKHaaPiQ6 wCldo8Io4qYEiEGuqbsRJ0QgWE5tD004dfnAKqf+u+aP+u4lyySsoLGURNqLnm3oym nbAHAuxWnOuQ1B28aRp3QXGRLIow3K+Lp/HuzsnA= X-UI-Sender-Class: c548c8c5-30a9-4db5-a2e7-cb6cb037b8f9 Received: from laptop.manuel.cli.intranet ([109.192.218.194]) by smtp.web.de (mrweb102 [213.165.67.124]) with ESMTPSA (Nemesis) id 0MMmx9-1hCwtg42Pf-008eRy for ; Tue, 16 Apr 2019 23:30:52 +0200 To: linux-block@vger.kernel.org From: Manuel Bentele Subject: Adding QCOW2 reading/writing support Openpgp: id=5260D26DAE5C7FDF3113C572EC7CB9F864CA371E Autocrypt: addr=manuel-bentele@web.de; prefer-encrypt=mutual; keydata= mQINBFRuF5QBEADSKWiJGL8clIeZM8RloahGhed7PsZF8xSVUF+XdnW3ETvethmgUyZvCgll eWpnVTJ/+kvqQ06PAEvpdEKYG8aIwpXyC3WzZVuuCRJrKRRfEGcCTX7dl0qPYqAUCy3XA1fL Bp67CjmyhiNUUigqjGaN4Frce7QIZaxO0DWFDK/6V7hQG+MKFTMYKEBmHjxPjnVAOQTsb862 CvitiysI8eSpICmBvRF8yOYT535RZ16FGx9Ny5HqLaPYqXeyXhAIlAJuREQI68nh7ZiiAkLE c11AanWBWwd8y8oMr9f4aPU+pTh1IkZ3fTZJa4jK9H2BDlk811In3Ig3tqFNJSZbv5BJ505f GeHP4+MANIQmk/Li0+xrjGyCFisFyVE/KZGRqirLKgr66ydYTj3RZh5AFa3g0hp/gXqEy1Vo UwV1sxKpGhwtOLr7sGADVL6S+Se/v63Wcpce2Yp8AIWQS8GiqH8ozBcNfgBD9Ku4hzedsEq4 kJqBIT4+mAg4OBkI4a8NYMVLyAQdgnjUliSEMGLM/rFBbAx26JoXL6b1dE2mjNV110OEpus8 7TsydJnCtryFVGZ2PtgCmupVySdIIfndMK4ExOe0/MndbhVott5Dsdr77EU5Z3LVSuRrr2T5 oDIPQrU5gjjjWzG8yo/6B4jkp/pa5dfcayOXvk9kN8WOzSAHLQARAQABtCZNYW51ZWwgQmVu dGVsZSA8bWFudWVsLWJlbnRlbGVAd2ViLmRlPokCOAQTAQIAIgUCVG4XlAIbAwYLCQgHAwIG FQgCCQoLBBYCAwECHgECF4AACgkQ7Hy5+GTKNx5qnQ/+OzXlc+CjHh7zhyEiYNqyXHynph1L XdpWDZho2UOzA5aRR6IpmvYNNWsJ9KKq/HQaH4DZrsKkYodMuDPChJI1pZPoeXEaFWNvw+bD vuSL2f8jwA0nccYe7pr7qpK0Dn+0wSAWBK1hBhg00KylVj6wBLMro3ZSETi3bQJ+dOWUqawT dPKT2InMIdh32BEQ8ozgb5LEIwNIVzPrJwM2vvO3Ssv7MfgM2WCw8SOjsLZXMHZV+uGqvtie 3WENd9CgkLqBpIDGo30SqUThAwdlPPdLCVuQ8CXw1VMANAYFmAOvhGgm/iP7bjZBBfsc6J3N gcncuMj3ULuF3o0OdNwAJTffO6HmAbYEbUJqy7p8YlaPCesZVaEV1EZhPkEG0ABlv5NotJzI COKd2mS+RVg/FrjskuaUELbU/wqv8c5uyc4isScqmQY/xRGibeCFvYien1TbzoZGUnxeXr3H RKVhNPZ2zkcmrybHwUQ0M30D94OWc4v0M/gO6IXBGUOFWk3eAAxTlHM4HG5o2cu4Qu86T4QK fNHQURTYh7t/SDEHtMWjJz+EFqzrAgkMbOvFFQHlLqJcWOgoWRxTH0BBkYtrSdasIpkb65Ke SoBIYBQbQkesowYvIKJ+Z1RdV3HoBgvaj0qCzYorwdb0LZ3BRXGoQNsqqWk1MuOxi3SVHOGQ dvTdMcW5Ag0EVG4XlAEQALgpoTS9qJv65lEjlngeDX71eF5zjmZMdZYqtlrfEiipsoYUM/8c MGY6v2Mz/ZmWxLdKD/u9AtcTvikzOr0JyWsRlaGesnsyaSzYMBhbTkI6yLJL0qSQsedet4HK LXOerBmMxWhmzjlnmlf/xDDfn5dm3CJfes6Q3/WVCGAhcWMizWExLhopw58idmLDdk0xQ7+n KdCMTYY0lZr4Hq34/nRVLc+umJzKB7QrCK3otOefl8APjsMdi+Od4m64Fq8ofELvR1VIhlKG ljINWw1qO4JvmHimYSAX/iB46Mi6j5uq+yQytRqvDAiYS0F9gd0vPVnHj1iB/MZ9GmX+4pdd 9g5aSPK7M4wiNiwBjRHDZxQNe/V6vq7z0xmHK5pTUIB39Fq1McJNNT/zaACQieQOe7BFSI83 vQTcihA5pJMyltbir8rzlQskX6hLxe4VYgvhsddzl9GBK03FK2FR8QVxHF7XxorzTT+sBO1n 1j9w2s8shnVn4A/shfCCROa11XjPpaoVVk57CRfhjtweDbZobppWenLntYcyxQPaUQbLJau4 1rUqvJBjyTNZq+GdLe74wvw70JVjHfEJ8mWMeUU7zFlGiNONi8itDTunHVqUcYolWc9uZL3M BN+AbeEpunORj6c961tznlYenDvXWdegQfXp7XE5TuHIMsWduwIIdb8PABEBAAGJAh8EGAEC AAkFAlRuF5QCGwwACgkQ7Hy5+GTKNx4dRw//UTFwzwyUBDgim8AVuWvEKO3dbdzeqOJpcRKz QLU/e4GmUpFoExCPk4mriIeeTXet3zMlDjGeHYv6eJ/OEtq8fIY0289kogOXpJD+95ap9mbU 7ngviMA9NA477zSfzMtnmJNnI2JNdHspFOH5CC1pMb5WRjC4gfpZqqWdWaZn4E3PNkhGtStY C7t7XPOd1jIBMqwtOvu3x2/F42zZoUWYKsJH0EmDCX+35x5Ltk15CI0AXRm+3ioAwenBlgqO F/6DVPMnJzhr83W6eGtH8lHpnwm5Pburp6M5G5k27pFgl43odOsPdg5/zVPHu8l8vtN2aKUi IU15IJvgpYoTUlDQuGiQXJvsLMllYUb9QRFKPQZaO/Y1kDSRyOoqOCRwBtopBP2b5OT+0yHx V1pqrxWv2IeYKqZBsVHEt3I5S7htNNI8Gfe1qRzW6z9Zel3USKfONPNdfXEWJabmUmYqN8LU l6CLC1wCCAKS501ZWA67kavA4y8nwNclx5tH7XjfUM5/MXGZhHFPAwTGM4Dx0i/WAXtLm194 9OqL4oczsIrWUxhPn0ThhmLs83yq5KnSVAk6QJ33pBeqjhv/ldnkdjdNRndK2nQVlUY3YTKU 6RyAs7xxGfGXYzE+ilN0+lyynMdxmv7GqZIQo+EiAk7ZfvCx4kB5Jp3+eREFBxStrEjz3Lo= Message-ID: <60bbe5e0-317d-8ead-0eb8-d1dc79927bc8@web.de> Date: Tue, 16 Apr 2019 23:30:51 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Content-Language: en-US X-Provags-ID: V03:K1:dWxNGanJqt38yRPjouHSINLSxd6mjUPFOTxYZpewEmWBixxn/lI r4fYOG437KsDG0NxJ6BaWFkXvcmmrEKRnJOoh8ZTtSQF9xMIeQm4Sbb7UuZ+w7KPDG+2RKd Lu13/v7sdLaqo3r+eTqXmtqmg/IG6ZteGiv01W7ou1U8e9mNG95N7VgdzxZVYEBUhoxCf9U a5938L9eJmRb2Ji4Wfe3w== X-UI-Out-Filterresults: notjunk:1;V03:K0:4BC4lKF/pSQ=:8kwGuWw/GWA2YLMfLrPfzK OYJ6dyixY+37ULFsSmeRHVUKj/t+BoYuKzeX0DUuTi/QIlIgkH14RKEBw7BDwerbotK0vuk9d HkKWuePX2UmsOmdW2NRT39uTl8gtybsQDk1dwzd7fyj2a9Oo8Ecxt6dVryWMkT11c+s1ARGRO xB77oJJ0v8Lzt4UDnSUSBtOnYNuzeWwRQvoil53n4w8H65kK2a4llhvILbFbd0Q9X7HJegadt +fgiSONVF7nprsTzala7GsgSToMkigaPmnGuBzR+tn4rYcLiOiy54M6Zt+R6pfeVOblsdjRTM VKjCwcA+VaWITB8IKOTcVi7Q8k1DE9t1v62EmDW9jmUjVFr5iKwC4JDG7vnrKDetnlm0Gi/8r uMa14fGd+0P730JNnGb3Vz3sZW+SJuW4X2eBzU2iEFcwf2g0AJMHUrSuahU8Ytno5cqboJt0D 9p6PmUDdGcc076kVGgkBvNVEKofLefCxZ+iPryy5XSC/y0Yo4tq8K4lCrRmxsZRMvhTkV0u2j B1N00pxWTeyf6qJYA3wPPnASPBxl6QBnqpe7Cn9Yk0sV98ZeP0ZYVyAjYVDQsfbfwdUHh0SDt f4d7Mc+QfDNgd/YqjMaiOaeHz+URref1EHvquiUF5VoVQm5/IBvFGbejDDvJEAHpQaNlDm3Wp RFcEyv7jmOI0xkNJuE3wdTFOyDM748XJUjjWUp+9mC8fUQl/UZNPc4+ap/scqdof+VWhZpbkH bAyXyI2ydc0nb56NsBeLnl83Qf6K5eUUftwGF+ASMDdFor5SwwAFX0CjkCjIEv+7Y2LW8zZFg QX22ray8Xl8plmhDjyiKCiFtNqTiiv7qA8DpmKvFam7AWvspde9rN1eljWuCIohaY7njrlkFz cQVIRc3w9xPIAz97+XJ4uOdgdoUWHIUC5c0mnoG/ma+mo4i3NM0opmckBLEvRUj05jv3ycOtQ OapwhykuLUw== Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Hi everyone I'm going to implement an in-kernel reading of QCOW2 images. In the project, I only need the reading of QCOW2 images, but it's essential to make thoughts for the implementation of the writing, too. One of the difficulties seems to be the support of making an image sparse (resizing the disk image). Now, I want to ask you for advice: What is the best approach to achieve this? =C2=A0 * Implement the reading/writing in the device mapper? =C2=A0 * Extend the loop device? =C2=A0 * Create a new subsystem for the processing of sparse devices or im= ages? Or do you have any other idea? Regards, Manuel Bentele