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=-3.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT 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 96ABAC43331 for ; Wed, 13 Nov 2019 13:42:31 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (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 E909F22459 for ; Wed, 13 Nov 2019 13:42:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="bFor07CL" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E909F22459 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 47Cm500YcXzF7SJ for ; Thu, 14 Nov 2019 00:42:28 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=bombadil.srs.infradead.org (client-ip=2607:7c80:54:e::133; helo=bombadil.infradead.org; envelope-from=batv+b6a0ef5c1751a0763e03+5925+infradead.org+hch@bombadil.srs.infradead.org; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=infradead.org header.i=@infradead.org header.b="bFor07CL"; dkim-atps=neutral Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 47ClzN5FkmzF7cs for ; Thu, 14 Nov 2019 00:37:35 +1100 (AEDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: MIME-Version:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To:Content-Type: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=rXc6QoCjcK1fWhu8XRtkOP3UczvVAyRhRkKSV31pqqU=; b=bFor07CLRIOg9YoQ7IHm/cB8W hIdGbFb1njbAVrpUQdjFjesLOX1WnXAFGw2pmnHSNTm81yc3bNalr5a013MlgrHy2k8zz5sgrxxRI 3NOx1YPtfD+HhiWw/ijEAP4y4eC5bJYgtFWuSO1drKdGcBrSfoxS2rFJs3Q+klQQs8sxntRYznHQC zIfN/V3b0xC7OhOFui/EgHwb+bX3f13IP38BMZyt+CCdA6r1tvBX/kGHXthO0XGnTEjH/t8VyKwW1 mfgvknItIypIHg0YD3UH+lPMm9B0tQAvyPIwoUPJ8WzpLPnVBkY9zdsmG1pabm/PNYEHSr9eQ9k5m yk33iGgkQ==; Received: from clnet-p19-102.ikbnet.co.at ([83.175.77.102] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1iUspw-0008Mt-Me; Wed, 13 Nov 2019 13:37:33 +0000 From: Christoph Hellwig To: iommu@lists.linux-foundation.org, Alexey Kardashevskiy Subject: generic DMA bypass flag Date: Wed, 13 Nov 2019 14:37:29 +0100 Message-Id: <20191113133731.20870-1-hch@lst.de> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Greg Kroah-Hartman , linuxppc-dev@lists.ozlabs.org, Robin Murphy , linux-kernel@vger.kernel.org, Lu Baolu Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Hi all, I've recently beeing chatting with Lu about using dma-iommu and per-device DMA ops in the intel IOMMU driver, and one missing feature in dma-iommu is a bypass mode where the direct mapping is used even when an iommu is attached to improve performance. The powerpc code already has a similar mode, so I'd like to move it to the core DMA mapping code. As part of that I noticed that the current powerpc code has a little bug in that it used the wrong check in the dma_sync_* routines to see if the direct mapping code is used. These two patches just add the generic code and move powerpc over, the intel IOMMU bits will require a separate discussion. The x86 AMD Gart code also has a bypass mode, but it is a lot strange, so I'm not going to touch it for now.