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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 071F9C3A59D for ; Fri, 16 Aug 2019 22:40:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C6D9B206C1 for ; Fri, 16 Aug 2019 22:40:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727882AbfHPWkq (ORCPT ); Fri, 16 Aug 2019 18:40:46 -0400 Received: from foss.arm.com ([217.140.110.172]:34200 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727660AbfHPWkq (ORCPT ); Fri, 16 Aug 2019 18:40:46 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 028F6344; Fri, 16 Aug 2019 15:40:46 -0700 (PDT) Received: from [10.37.12.84] (unknown [10.37.12.84]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id A8B533F718; Fri, 16 Aug 2019 15:40:44 -0700 (PDT) Subject: Re: [Xen-devel] [PATCH 07/11] swiotlb-xen: provide a single page-coherent.h header To: Christoph Hellwig , Stefano Stabellini , Konrad Rzeszutek Wilk Cc: xen-devel@lists.xenproject.org, iommu@lists.linux-foundation.org, x86@kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org References: <20190816130013.31154-1-hch@lst.de> <20190816130013.31154-8-hch@lst.de> From: Julien Grall Message-ID: <9a3261c6-5d92-cf6b-1ae8-3a8e8b5ef0d4@arm.com> Date: Fri, 16 Aug 2019 23:40:43 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20190816130013.31154-8-hch@lst.de> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 8/16/19 2:00 PM, Christoph Hellwig wrote: > Merge the various page-coherent.h files into a single one that either > provides prototypes or stubs depending on the need for cache > maintainance. > > For extra benefits alo include in the file > actually implementing the interfaces provided. > > Signed-off-by: Christoph Hellwig > --- > arch/arm/include/asm/xen/page-coherent.h | 2 -- > arch/arm/xen/mm.c | 1 + > arch/arm64/include/asm/xen/page-coherent.h | 2 -- > arch/x86/include/asm/xen/page-coherent.h | 22 ------------------ > drivers/xen/swiotlb-xen.c | 4 +--- > include/Kbuild | 2 +- > include/xen/{arm => }/page-coherent.h | 27 +++++++++++++++++++--- I am not sure I agree with this rename. The implementation of the helpers are very Arm specific as this is assuming Dom0 is 1:1 mapped. This was necessary due to the lack of IOMMU on Arm platforms back then. But this is now a pain to get rid of it on newer platform... Cheers, -- Julien Grall