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=-8.5 required=3.0 tests=BAYES_00, 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 A1BE1C433E2 for ; Tue, 1 Sep 2020 13:55:14 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (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 6BC3A206FA for ; Tue, 1 Sep 2020 13:55:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6BC3A206FA Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=alpha.franken.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id 223C886364; Tue, 1 Sep 2020 13:55:14 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id u2-y7jBzA9xC; Tue, 1 Sep 2020 13:55:13 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by fraxinus.osuosl.org (Postfix) with ESMTP id BDC7E86243; Tue, 1 Sep 2020 13:55:13 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id AA84AC07FF; Tue, 1 Sep 2020 13:55:13 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id 1F111C0051 for ; Tue, 1 Sep 2020 13:55:13 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id 17520862D4 for ; Tue, 1 Sep 2020 13:55:13 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Zz8HmE3YtNzu for ; Tue, 1 Sep 2020 13:55:11 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from elvis.franken.de (elvis.franken.de [193.175.24.41]) by fraxinus.osuosl.org (Postfix) with ESMTP id C110B862C9 for ; Tue, 1 Sep 2020 13:55:11 +0000 (UTC) Received: from uucp (helo=alpha) by elvis.franken.de with local-bsmtp (Exim 3.36 #1) id 1kD6kf-0001nf-02; Tue, 01 Sep 2020 15:55:09 +0200 Received: by alpha.franken.de (Postfix, from userid 1000) id 62CB0C0E4C; Tue, 1 Sep 2020 15:53:04 +0200 (CEST) Date: Tue, 1 Sep 2020 15:53:04 +0200 From: Thomas Bogendoerfer To: Christoph Hellwig Subject: Re: [PATCH 08/28] MIPS: make dma_sync_*_for_cpu a little less overzealous Message-ID: <20200901135304.GC11944@alpha.franken.de> References: <20200819065555.1802761-1-hch@lst.de> <20200819065555.1802761-9-hch@lst.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200819065555.1802761-9-hch@lst.de> User-Agent: Mutt/1.5.23 (2014-03-12) Cc: alsa-devel@alsa-project.org, linux-ia64@vger.kernel.org, linux-doc@vger.kernel.org, nouveau@lists.freedesktop.org, linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, "James E.J. Bottomley" , linux-mm@kvack.org, linux-samsung-soc@vger.kernel.org, Joonyoung Shim , linux-scsi@vger.kernel.org, Kyungmin Park , Ben Skeggs , Matt Porter , linux-media@vger.kernel.org, Tom Lendacky , Pawel Osciak , Mauro Carvalho Chehab , linux-arm-kernel@lists.infradead.org, linux-parisc@vger.kernel.org, netdev@vger.kernel.org, Seung-Woo Kim , linux-mips@vger.kernel.org, iommu@lists.linux-foundation.org X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 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 Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On Wed, Aug 19, 2020 at 08:55:35AM +0200, Christoph Hellwig wrote: > When transferring DMA ownership back to the CPU there should never > be any writeback from the cache, as the buffer was owned by the > device until now. Instead it should just be invalidated for the > mapping directions where the device could have written data. > Note that the changes rely on the fact that kmap_atomic is stubbed > out for the !HIGHMEM case to simplify the code a bit. > > Signed-off-by: Christoph Hellwig > --- > arch/mips/mm/dma-noncoherent.c | 44 +++++++++++++++++++++------------- > 1 file changed, 28 insertions(+), 16 deletions(-) Acked-by: Thomas Bogendoerfer -- Crap can work. Given enough thrust pigs will fly, but it's not necessarily a good idea. [ RFC1925, 2.3 ] _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu