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 32A81C4332E for ; Fri, 20 Mar 2020 14:22:11 +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 9EFD62070A for ; Fri, 20 Mar 2020 14:22:10 +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="B6/zKn9h" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9EFD62070A 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 48kQvh2HcRzDx3Q for ; Sat, 21 Mar 2020 01:22:08 +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+e7fddad6f7a51abe8bfe+6053+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.a=rsa-sha256 header.s=bombadil.20170209 header.b=B6/zKn9h; 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 48kQr75tq0zDsGv for ; Sat, 21 Mar 2020 01:19:03 +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:In-Reply-To:References; bh=fP76rVZ78wXp8cMUTCCjVQv5iPeDciWQiuxMnftZdbU=; b=B6/zKn9hIGXiUR1+IFAOol+kv1 XjmHCPdWqbtmD9fPyqucY8V+g+o9OLOvI3t+vrDdb/DQOqyScEnQli0GsUE5QpHE3YjdPBKaRCK68 rQSN6kmN+N0Smxlwq+SoFYRFj3SxRcSTi1Yh+KaTdPyhzA+m1CzeAqONaNmB+4ZAaLWxYwgTBl+jb ILStHKt07ubvKmWQ63yuEZKU86Ihy8RxKbgZoXwxkIDn8QKjcBqMVb/ZK6RXAsYaxHRY42JJ2qj0L 6LlhF9zgzO3uCzN93uOom5TnQF6sMVJq6DscqerEEnHaIo7nFdfFl+Nips+DMKRf9Hob7GPC7Kewo JcfqGpuA==; Received: from 089144202225.atnat0011.highway.a1.net ([89.144.202.225] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jFIUF-0007Ej-D6; Fri, 20 Mar 2020 14:18:59 +0000 From: Christoph Hellwig To: iommu@lists.linux-foundation.org, Alexey Kardashevskiy Subject: generic DMA bypass flag v2 Date: Fri, 20 Mar 2020 15:16:38 +0100 Message-Id: <20200320141640.366360-1-hch@lst.de> X-Mailer: git-send-email 2.25.1 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 , Joerg Roedel , Robin Murphy , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.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. Changes since v1: - rebased to the current dma-mapping-for-next tree