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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 935F1C433DB for ; Fri, 19 Mar 2021 20:09:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 62CC16194C for ; Fri, 19 Mar 2021 20:09:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230409AbhCSUIs (ORCPT ); Fri, 19 Mar 2021 16:08:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43994 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230461AbhCSUIZ (ORCPT ); Fri, 19 Mar 2021 16:08:25 -0400 Received: from mail-lf1-x133.google.com (mail-lf1-x133.google.com [IPv6:2a00:1450:4864:20::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 99ABBC06175F for ; Fri, 19 Mar 2021 13:08:24 -0700 (PDT) Received: by mail-lf1-x133.google.com with SMTP id q13so11839025lfu.8 for ; Fri, 19 Mar 2021 13:08:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=l/0awmwbYpldGtvhGbGrjtgg5S5AmtnvrJ31RfQjWzg=; b=Udu99pfuLvrG3/uGIHBn854uuyD2MnagNpLodzU1KeSa2MMu8iHwpvgaE2s5sLcD22 weRb6idNCOSd97o1eHiD3ISp6GYnVz2SUXOIzQcXDYj1Oz/8mwXreNqGUuJeQNjkMvkB hBIs/RjQ8pcafCqVnLFRmLTU+wZUiLkOdJY5E= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=l/0awmwbYpldGtvhGbGrjtgg5S5AmtnvrJ31RfQjWzg=; b=hzVHyIauxjoYotrcgLzruRZY6dKyTAFV3YW4o24Im3Y9hdko/45uQ9GDUfNuRlsF52 ubOgqYGJwInIs3/L3+RTd3UfJZu+O3a4LZ0Ik5p5YK2T8g/jooPIB04Qx+CTcP8C7mem WwShnkn0NLw5SQuYk5k85E2dDJnMO+/YCBNGxKlY25W9JMgr+pXtmHDINOXEsWX4GhPI Ryx2htXt29hoSuNWJTR/EnejKSlIoCqNKiYwH1oHPuTZFCgIdUc2+q9LZDoNEZeHJ0q2 9/yyPXcBImdq/fW8p2dCxtmYyrr7iJ4a3jxpe5Iy2Xj4oZFa+r+zR/yOZv/w01x8nziG UPLQ== X-Gm-Message-State: AOAM530Zq22+R60OW7oNOMLhE5GoogzmVpFROiLmrnmSnxO/3yDmgtZQ upiA87eCHuhDDBQe83dzk2o8HG51jbBF4Q== X-Google-Smtp-Source: ABdhPJzTZ3e6VolEoYrdKqjlClgvhkaJ13wC7BpD79lYwHlUZ5hs0lqoJp7O0P0/ft00AZYgAo3+rw== X-Received: by 2002:a05:6512:31d6:: with SMTP id j22mr1725400lfe.637.1616184502948; Fri, 19 Mar 2021 13:08:22 -0700 (PDT) Received: from mail-lf1-f43.google.com (mail-lf1-f43.google.com. [209.85.167.43]) by smtp.gmail.com with ESMTPSA id 200sm134579lfm.215.2021.03.19.13.08.21 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 19 Mar 2021 13:08:22 -0700 (PDT) Received: by mail-lf1-f43.google.com with SMTP id o10so11840266lfb.9 for ; Fri, 19 Mar 2021 13:08:21 -0700 (PDT) X-Received: by 2002:a05:6512:33cc:: with SMTP id d12mr1663604lfg.487.1616184501624; Fri, 19 Mar 2021 13:08:21 -0700 (PDT) MIME-Version: 1.0 References: <8f741746-fd7f-c81a-3cdf-fb81aeea34b5@toxicpanda.com> In-Reply-To: <8f741746-fd7f-c81a-3cdf-fb81aeea34b5@toxicpanda.com> From: Linus Torvalds Date: Fri, 19 Mar 2021 13:08:05 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v8 00/10] fs: interface for directly reading/writing compressed data To: Josef Bacik Cc: Omar Sandoval , linux-fsdevel , linux-btrfs , Al Viro , Christoph Hellwig , Dave Chinner , Jann Horn , Amir Goldstein , Aleksa Sarai , Linux API , Kernel Team Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On Fri, Mar 19, 2021 at 11:21 AM Josef Bacik wrote: > > Can we get some movement on this? Omar is sort of spinning his wheels here > trying to get this stuff merged, no major changes have been done in a few > postings. I'm not Al, and I absolutely detest the IOCB_ENCODED thing, and want more explanations of why this should be done that way, and pollute our iov_iter handling EVEN MORE. Our iov_iter stuff isn't the most legible, and I don't understand why anybody would ever think it's a good idea to spread what is clearly a "struct" inside multiple different iov extents. Honestly, this sounds way more like an ioctl interface than read/write. We've done that before. But if it has to be done with an iov_iter, is there *any* reason to not make it be a hard rule that iov[0] should not be the entirely of the struct, and the code shouldn't ever need to iterate? Also I see references to the man-page, but honestly, that's not how the kernel UAPI should be defined ("just read the man-page"), plus I refuse to live in the 70's, and consider troff to be an atrocious format. So make the UAPI explanation for this horror be in a legible format that is actually part of the kernel so that I can read what the intent is, instead of having to decode hieroglypics. Linus