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=-9.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 84218C433DB for ; Mon, 4 Jan 2021 17:27:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3EAB8224F4 for ; Mon, 4 Jan 2021 17:27:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726418AbhADR1g (ORCPT ); Mon, 4 Jan 2021 12:27:36 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59296 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726189AbhADR1g (ORCPT ); Mon, 4 Jan 2021 12:27:36 -0500 Received: from mail-wm1-x329.google.com (mail-wm1-x329.google.com [IPv6:2a00:1450:4864:20::329]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E257BC061574; Mon, 4 Jan 2021 09:26:55 -0800 (PST) Received: by mail-wm1-x329.google.com with SMTP id c133so19190460wme.4; Mon, 04 Jan 2021 09:26:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=to:cc:references:from:autocrypt:subject:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=vhZcYxw85hQr217njjB88qNCX1pBfOIpilSgl/Wkqsk=; b=lIvmXiWTK3tUPBqWNrMOzheIsKhz7ZK+Gj2aSDsVfam72rOuxAWCFOkzIuJi0UsLxv xkwkBKgOZrfHKM85yWWIlww4h1ZvB7yUwzfOAux3kdtbgfSf7h8ivjwrcNh0p7y4HdNn 8itAJ2XuJmi6vDeWNuCqW8VYRh4gv8hdJgmnQoEqKbIWb+Z4KEXZAwuMyoNLr4IZR8jI aTmi9sZmmEOpaM0ggqRxS6kazZP8OR3uyS96Lq6tPI2PfijJtUEAo1vQIINoegC9aWFy S6BEMFntgGhUvDevrkxH3KYGt7t5GANVjxTQL/cE9qrO2Ya1x8yU1lytKf1xWEgbON8c rbyA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:to:cc:references:from:autocrypt:subject :message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=vhZcYxw85hQr217njjB88qNCX1pBfOIpilSgl/Wkqsk=; b=R89yQVPBe9zPNaNQl9mzlOv6HbF/VlmlsMsVggmBS7xVQH/bKDC1G+tB1m6bRG/5Ro 1aMbVgv/mIHDR2qyfroYXiu/G4Ehe1xSoFe8KTs1JZ28phRzLYTBgyDdjiu91HtSjSa4 0H5SnLu62t91zlRxs0sq+R6vPhu6eWwSYWS34zjQ98Ag28bNLZsfLmE7F5F1RSNhtdrR 6XggWy2CI+dZLI3DwbGgNXhhKWnVquN9wXcL9SNrdXTQ89GIdOPfOPDoEWuXWNr3bTVs BB+Ot7Q6/LESowPwk/25+6swQLHIh4mrRsikx3dRngz195xeUHVTAEDxlUhdyPYc0Q4Q qTdw== X-Gm-Message-State: AOAM530gbRC2rybgYFCurWYF3oyFzyJSEi67AzJLEgxT/KrsgegYR3gA ZkSguTF79uIQd183DS4EAV0eSW+uqZSQr7w0 X-Google-Smtp-Source: ABdhPJwKi+A2PZ7gJsqOn5Ymq1PeYPvYx8txZ71YhsB/T4YTc39zWcuXj3Vp193rQV2REjlyyPEgXQ== X-Received: by 2002:a7b:cf30:: with SMTP id m16mr27225859wmg.145.1609781214488; Mon, 04 Jan 2021 09:26:54 -0800 (PST) Received: from [192.168.8.190] ([85.255.233.205]) by smtp.gmail.com with ESMTPSA id n14sm5213wmi.1.2021.01.04.09.26.53 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 04 Jan 2021 09:26:54 -0800 (PST) To: Matthew Wilcox Cc: linux-block@vger.kernel.org, Jens Axboe , Christoph Hellwig , Ming Lei , Johannes Weiner , Alexander Viro , "Darrick J . Wong" , "Martin K . Petersen" , Jonathan Corbet , linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, io-uring@vger.kernel.org, linux-kernel@vger.kernel.org, target-devel@vger.kernel.org, linux-scsi@vger.kernel.org, linux-doc@vger.kernel.org References: <20210104163755.GA22407@casper.infradead.org> From: Pavel Begunkov Autocrypt: addr=asml.silence@gmail.com; prefer-encrypt=mutual; keydata= mQINBFmKBOQBEAC76ZFxLAKpDw0bKQ8CEiYJRGn8MHTUhURL02/7n1t0HkKQx2K1fCXClbps bdwSHrhOWdW61pmfMbDYbTj6ZvGRvhoLWfGkzujB2wjNcbNTXIoOzJEGISHaPf6E2IQx1ik9 6uqVkK1OMb7qRvKH0i7HYP4WJzYbEWVyLiAxUj611mC9tgd73oqZ2pLYzGTqF2j6a/obaqha +hXuWTvpDQXqcOZJXIW43atprH03G1tQs7VwR21Q1eq6Yvy2ESLdc38EqCszBfQRMmKy+cfp W3U9Mb1w0L680pXrONcnlDBCN7/sghGeMHjGKfNANjPc+0hzz3rApPxpoE7HC1uRiwC4et83 CKnncH1l7zgeBT9Oa3qEiBlaa1ZCBqrA4dY+z5fWJYjMpwI1SNp37RtF8fKXbKQg+JuUjAa9 Y6oXeyEvDHMyJYMcinl6xCqCBAXPHnHmawkMMgjr3BBRzODmMr+CPVvnYe7BFYfoajzqzq+h EyXSl3aBf0IDPTqSUrhbmjj5OEOYgRW5p+mdYtY1cXeK8copmd+fd/eTkghok5li58AojCba jRjp7zVOLOjDlpxxiKhuFmpV4yWNh5JJaTbwCRSd04sCcDNlJj+TehTr+o1QiORzc2t+N5iJ NbILft19Izdn8U39T5oWiynqa1qCLgbuFtnYx1HlUq/HvAm+kwARAQABtDFQYXZlbCBCZWd1 bmtvdiAoc2lsZW5jZSkgPGFzbWwuc2lsZW5jZUBnbWFpbC5jb20+iQJOBBMBCAA4FiEE+6Ju PTjTbx479o3OWt5b1Glr+6UFAlmKBOQCGwMFCwkIBwIGFQgJCgsCBBYCAwECHgECF4AACgkQ Wt5b1Glr+6WxZA//QueaKHzgdnOikJ7NA/Vq8FmhRlwgtP0+E+w93kL+ZGLzS/cUCIjn2f4Q Mcutj2Neg0CcYPX3b2nJiKr5Vn0rjJ/suiaOa1h1KzyNTOmxnsqE5fmxOf6C6x+NKE18I5Jy xzLQoktbdDVA7JfB1itt6iWSNoOTVcvFyvfe5ggy6FSCcP+m1RlR58XxVLH+qlAvxxOeEr/e aQfUzrs7gqdSd9zQGEZo0jtuBiB7k98t9y0oC9Jz0PJdvaj1NZUgtXG9pEtww3LdeXP/TkFl HBSxVflzeoFaj4UAuy8+uve7ya/ECNCc8kk0VYaEjoVrzJcYdKP583iRhOLlZA6HEmn/+Gh9 4orG67HNiJlbFiW3whxGizWsrtFNLsSP1YrEReYk9j1SoUHHzsu+ZtNfKuHIhK0sU07G1OPN 2rDLlzUWR9Jc22INAkhVHOogOcc5ajMGhgWcBJMLCoi219HlX69LIDu3Y34uIg9QPZIC2jwr 24W0kxmK6avJr7+n4o8m6sOJvhlumSp5TSNhRiKvAHB1I2JB8Q1yZCIPzx+w1ALxuoWiCdwV M/azguU42R17IuBzK0S3hPjXpEi2sK/k4pEPnHVUv9Cu09HCNnd6BRfFGjo8M9kZvw360gC1 reeMdqGjwQ68o9x0R7NBRrtUOh48TDLXCANAg97wjPoy37dQE7e5Ag0EWYoE5AEQAMWS+aBV IJtCjwtfCOV98NamFpDEjBMrCAfLm7wZlmXy5I6o7nzzCxEw06P2rhzp1hIqkaab1kHySU7g dkpjmQ7Jjlrf6KdMP87mC/Hx4+zgVCkTQCKkIxNE76Ff3O9uTvkWCspSh9J0qPYyCaVta2D1 Sq5HZ8WFcap71iVO1f2/FEHKJNz/YTSOS/W7dxJdXl2eoj3gYX2UZNfoaVv8OXKaWslZlgqN jSg9wsTv1K73AnQKt4fFhscN9YFxhtgD/SQuOldE5Ws4UlJoaFX/yCoJL3ky2kC0WFngzwRF Yo6u/KON/o28yyP+alYRMBrN0Dm60FuVSIFafSqXoJTIjSZ6olbEoT0u17Rag8BxnxryMrgR dkccq272MaSS0eOC9K2rtvxzddohRFPcy/8bkX+t2iukTDz75KSTKO+chce62Xxdg62dpkZX xK+HeDCZ7gRNZvAbDETr6XI63hPKi891GeZqvqQVYR8e+V2725w+H1iv3THiB1tx4L2bXZDI DtMKQ5D2RvCHNdPNcZeldEoJwKoA60yg6tuUquvsLvfCwtrmVI2rL2djYxRfGNmFMrUDN1Xq F3xozA91q3iZd9OYi9G+M/OA01husBdcIzj1hu0aL+MGg4Gqk6XwjoSxVd4YT41kTU7Kk+/I 5/Nf+i88ULt6HanBYcY/+Daeo/XFABEBAAGJAjYEGAEIACAWIQT7om49ONNvHjv2jc5a3lvU aWv7pQUCWYoE5AIbDAAKCRBa3lvUaWv7pfmcEACKTRQ28b1y5ztKuLdLr79+T+LwZKHjX++P 4wKjEOECCcB6KCv3hP+J2GCXDOPZvdg/ZYZafqP68Yy8AZqkfa4qPYHmIdpODtRzZSL48kM8 LRzV8Rl7J3ItvzdBRxf4T/Zseu5U6ELiQdCUkPGsJcPIJkgPjO2ROG/ZtYa9DvnShNWPlp+R uPwPccEQPWO/NP4fJl2zwC6byjljZhW5kxYswGMLBwb5cDUZAisIukyAa8Xshdan6C2RZcNs rB3L7vsg/R8UCehxOH0C+NypG2GqjVejNZsc7bgV49EOVltS+GmGyY+moIzxsuLmT93rqyII 5rSbbcTLe6KBYcs24XEoo49Zm9oDA3jYvNpeYD8rDcnNbuZh9kTgBwFN41JHOPv0W2FEEWqe JsCwQdcOQ56rtezdCJUYmRAt3BsfjN3Jn3N6rpodi4Dkdli8HylM5iq4ooeb5VkQ7UZxbCWt UVMKkOCdFhutRmYp0mbv2e87IK4erwNHQRkHUkzbsuym8RVpAZbLzLPIYK/J3RTErL6Z99N2 m3J6pjwSJY/zNwuFPs9zGEnRO4g0BUbwGdbuvDzaq6/3OJLKohr5eLXNU3JkT+3HezydWm3W OPhauth7W0db74Qd49HXK0xe/aPrK+Cp+kU1HRactyNtF8jZQbhMCC8vMGukZtWaAwpjWiiH bA== Subject: Re: [PATCH v2 2/7] bvec/iter: disallow zero-length segment bvecs Message-ID: Date: Mon, 4 Jan 2021 17:23:24 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.3.0 MIME-Version: 1.0 In-Reply-To: <20210104163755.GA22407@casper.infradead.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 04/01/2021 16:37, Matthew Wilcox wrote: > On Sat, Jan 02, 2021 at 03:17:34PM +0000, Pavel Begunkov wrote: >> --- a/Documentation/filesystems/porting.rst >> +++ b/Documentation/filesystems/porting.rst >> @@ -865,3 +865,10 @@ no matter what. Everything is handled by the caller. >> >> clone_private_mount() returns a longterm mount now, so the proper destructor of >> its result is kern_unmount() or kern_unmount_array(). >> + >> +--- >> + >> +**mandatory** >> + >> +zero-length bvec segments are disallowed, they must be filtered out before >> +passed on to an iterator. > > Why are you putting this in filesystems/porting? Filesystems don't usually At least splice and a dozen of others do. As block apriori doesn't have them, it's mainly addressed to fs + net. > generate bvecs ... there's nothing in this current series that stops them. Yes, just mixing it with splice changes, which did all the work, looks awkward to me. Would you suggest another segregation for the patches? > I'd suggest Documentation/block/biovecs.rst or biodoc.rst (and frankly, > biodoc.rst needs a good cleanup) I'll add a note to biovecs.rst -- Pavel Begunkov