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, INCLUDES_PATCH,MAILING_LIST_MULTI,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 56FBAC433FF for ; Mon, 5 Aug 2019 09:11:01 +0000 (UTC) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 37E152067D for ; Mon, 5 Aug 2019 09:11:01 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 37E152067D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from mail.linux-foundation.org (localhost [127.0.0.1]) by mail.linuxfoundation.org (Postfix) with ESMTP id 03914D8D; Mon, 5 Aug 2019 09:11:01 +0000 (UTC) Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id A95C4CD3 for ; Mon, 5 Aug 2019 09:10:59 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp1.linuxfoundation.org (Postfix) with ESMTP id B6656829 for ; Mon, 5 Aug 2019 09:10:56 +0000 (UTC) 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 2AC9428; Mon, 5 Aug 2019 02:10:56 -0700 (PDT) Received: from iMac.local (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 4CDE03F694; Mon, 5 Aug 2019 02:10:54 -0700 (PDT) Date: Mon, 5 Aug 2019 10:10:52 +0100 From: Catalin Marinas To: Christoph Hellwig Subject: Re: [PATCH 1/2] dma-mapping: fix page attributes for dma_mmap_* Message-ID: <20190805091051.GB59981@iMac.local> References: <20190805080145.5694-1-hch@lst.de> <20190805080145.5694-2-hch@lst.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20190805080145.5694-2-hch@lst.de> User-Agent: Mutt/1.11.1 (2018-12-01) Cc: Gavin Li , Shawn Anastasio , Michael Ellerman , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Russell King , linux-mips@vger.kernel.org, iommu@lists.linux-foundation.org, Paul Burton , James Hogan , Will Deacon , linux-arm-kernel@lists.infradead.org, Robin Murphy X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: iommu-bounces@lists.linux-foundation.org Errors-To: iommu-bounces@lists.linux-foundation.org On Mon, Aug 05, 2019 at 11:01:44AM +0300, Christoph Hellwig wrote: > All the way back to introducing dma_common_mmap we've defaulyed to mark s/defaultyed/defaulted/ > the pages as uncached. But this is wrong for DMA coherent devices. > Later on DMA_ATTR_WRITE_COMBINE also got incorrect treatment as that > flag is only treated special on the alloc side for non-coherent devices. > > Introduce a new dma_pgprot helper that deals with the check for coherent > devices so that only the remapping cases even reach arch_dma_mmap_pgprot s/even/ever/ > diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c > index 1d3f0b5a9940..bd2b039f43a6 100644 > --- a/arch/arm64/mm/dma-mapping.c > +++ b/arch/arm64/mm/dma-mapping.c > @@ -14,9 +14,7 @@ > pgprot_t arch_dma_mmap_pgprot(struct device *dev, pgprot_t prot, > unsigned long attrs) > { > - if (!dev_is_dma_coherent(dev) || (attrs & DMA_ATTR_WRITE_COMBINE)) > - return pgprot_writecombine(prot); > - return prot; > + return pgprot_writecombine(prot); > } For arm64: Acked-by: Catalin Marinas _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu