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=-3.8 required=3.0 tests=BAYES_00, 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 88374C432BE for ; Sat, 28 Aug 2021 21:26:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6712960E77 for ; Sat, 28 Aug 2021 21:26:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232819AbhH1V1f (ORCPT ); Sat, 28 Aug 2021 17:27:35 -0400 Received: from mout.kundenserver.de ([212.227.126.130]:47959 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232532AbhH1V1e (ORCPT ); Sat, 28 Aug 2021 17:27:34 -0400 Received: from mail-wr1-f45.google.com ([209.85.221.45]) by mrelayeu.kundenserver.de (mreue011 [213.165.67.97]) with ESMTPSA (Nemesis) id 1MQdtO-1mgjKe2KGs-00Ng03; Sat, 28 Aug 2021 23:26:42 +0200 Received: by mail-wr1-f45.google.com with SMTP id u16so16201750wrn.5; Sat, 28 Aug 2021 14:26:42 -0700 (PDT) X-Gm-Message-State: AOAM530A0LiUb5m55CRPyLg2BpilximUExHXKjFmbgu5kb36U/dW/UEl /Fvaq/T9nepORjziTFtMXobrY6W5ELwjGkfp0Sk= X-Google-Smtp-Source: ABdhPJwvDnsDJcn3wIhFHRhkw8EPD/pggXR8T4gD9Xh87dD/CiOcm+8HpoR7LLiItw7WlQGpC2ld22sA7ZHK6OreHnU= X-Received: by 2002:adf:b781:: with SMTP id s1mr10383658wre.165.1630186002171; Sat, 28 Aug 2021 14:26:42 -0700 (PDT) MIME-Version: 1.0 References: <612A50C4.2080209@gmail.com> In-Reply-To: <612A50C4.2080209@gmail.com> From: Arnd Bergmann Date: Sat, 28 Aug 2021 23:26:26 +0200 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v1 0/4] char: xillybus: Remove usage of the deprecated 'pci-dma-compat.h' API To: Eli Billauer Cc: Christophe JAILLET , Arnd Bergmann , gregkh , Linux Kernel Mailing List , kernel-janitors@vger.kernel.org, Christoph Hellwig Content-Type: text/plain; charset="UTF-8" X-Provags-ID: V03:K1:SfZd/6/VPd+vpSJtwx98oNSjKSxpNw4Dj18VzVx1viyfokFzESd wka5xkyUfXDzcKtpH8aY2+X0PEqBErPaEnz4+VoHk5bLlU5LkRkSZBSKTYFWEVUgupriGZr 3LxbfkIaxA3aQbAUcEK5SrWFo1dNzrClxdomhxEQYivC47fZ/PDIXCxm63jbIV5YWykJXB8 KlDSXErMH0zSjSTmJ1DOw== X-UI-Out-Filterresults: notjunk:1;V03:K0:m86IDzp4oNs=:ZyFwd5QinI1i2btLgw+xMm qgb98PObe1/9td3pZRMt8C6PpPs3+SiiyMAJEIVwm6f9zdMNt0axPXkl8748nGRRLVy5XG1di E+VyHckvfm0NQkZOXJcHGmlzpuYgEcMXdw/f2Fj7+BYKSGXANvL+L8H6A1PFcO6+K4iY5tCb9 1AwNKlXPQp29r8JHxH8Lmc2nHp5JNsxsYTHYvUMfE83mDyZqRG0dZXjFtn3p+3g9Kj4uSv6oz OfO8shRm4lZeAmTof4MTvUyrkN52+zBUg6fGWnPwv1Fk1jkKpxkPCJHR2sxQ+fM4L/R1K+dK4 BGCREerzvECjJXTzgSN/s4Fg3cDGJ7GCMf3q/9XXieHBhXJ1zEaqUTZZxFna+Hii4TbT9VpXr bR9PSKFEm4U47kAO0DvbKg8M+CpOhAfw/c1GaHLtEJcZUt4+uWC9bzdftET7kGYLDC2P0OBtx 5+Bu4vuD1VwAqWbofZVaTABX1kCefzmiNj6nGALzpIn1OE6uqku6LDqGPLcUdutj22/uijEP9 Q875mTbRj0IjpqC2aMPqEuRWEw5+tMIg1qtZePGmb66mEFqcL5rBpFI3nWx+W/EAZO+w4/+EH dYAVDcLUIQfW+dCqTkLjUhUAXq1elmlMHlJJPHgv4vt0YL5OENNT7MNWViCVUN1+Buq0N5Ktg 3BESG7asFqp1knedtjrYXGMP7kF1BAqVeRP5bdxQPDw8bPLeud+rGtqce7pch/GR71/Lshjz7 ECsq9TFYg+IEcUONwTwf4jFA/69kH+uPrio4jA== Precedence: bulk List-ID: X-Mailing-List: kernel-janitors@vger.kernel.org On Sat, Aug 28, 2021 at 5:07 PM Eli Billauer wrote: > > On 27/08/21 20:17, Christophe JAILLET wrote: > > In [1], Christoph Hellwig has proposed to remove the wrappers in > > include/linux/pci-dma-compat.h. > > > Xillybus' driver is an example for why this is a good idea. But has this > been decided upon? Are we sure that there isn't a single platform where > the DMA mapping for PCI is different from non-PCI, and that such > platform will never be? Yes. > If so, is there any reference to that decision? The documentation was updated 11 years ago to only describe the modern linux/dma-mapping.h interfaces and mark the old bus-specific ones as no longer recommended, see 216bf58f4092 ("Documentation: convert PCI-DMA-mapping.txt to use the generic DMA API"). > I think the best way is to put a comment at the top of pci-dma-compat.h > saying that the functions in that header file are deprecated and will go > away soon. That would, more than anything else, convince people like me > to get rid of those PCI-DMA function calls. The only reason for keeping the old interface around any day longer would be to identify drivers that have been unmaintained for the past decade and ignored all the previous cleanup patches that got sent to them. Arnd