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=-8.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT 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 B8148C31E45 for ; Thu, 13 Jun 2019 08:43:16 +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 9D25620851 for ; Thu, 13 Jun 2019 08:43:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9D25620851 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.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 E1B911315; Thu, 13 Jun 2019 08:43:15 +0000 (UTC) Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 1C37F1307 for ; Thu, 13 Jun 2019 08:43:15 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from huawei.com (szxga04-in.huawei.com [45.249.212.190]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id BC284174 for ; Thu, 13 Jun 2019 08:43:13 +0000 (UTC) Received: from DGGEMS403-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id 7C2EF437288702CB4296; Thu, 13 Jun 2019 16:43:10 +0800 (CST) Received: from HGHY4L002753561.china.huawei.com (10.133.215.186) by DGGEMS403-HUB.china.huawei.com (10.3.19.203) with Microsoft SMTP Server id 14.3.439.0; Thu, 13 Jun 2019 16:42:59 +0800 From: Zhen Lei To: Jean-Philippe Brucker , John Garry , Robin Murphy , Will Deacon , Joerg Roedel , Jonathan Corbet , linux-doc , Sebastian Ott , Gerald Schaefer , "Martin Schwidefsky" , Heiko Carstens , Benjamin Herrenschmidt , Paul Mackerras , "Michael Ellerman" , Tony Luck , Fenghua Yu , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H . Peter Anvin" , David Woodhouse , iommu , linux-kernel , linux-s390 , linuxppc-dev , x86 , linux-ia64 Subject: [PATCH v9 1/7] iommu: enhance IOMMU default DMA mode build options Date: Thu, 13 Jun 2019 16:42:34 +0800 Message-ID: <20190613084240.16768-2-thunder.leizhen@huawei.com> X-Mailer: git-send-email 2.21.0.windows.1 In-Reply-To: <20190613084240.16768-1-thunder.leizhen@huawei.com> References: <20190613084240.16768-1-thunder.leizhen@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.133.215.186] X-CFilter-Loop: Reflected 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 First, add build option IOMMU_DEFAULT_{LAZY|STRICT}, so that we have the opportunity to set {lazy|strict} mode as default at build time. Then put the three config options in an choice, make people can only choose one of the three at a time. Signed-off-by: Zhen Lei --- drivers/iommu/Kconfig | 44 ++++++++++++++++++++++++++++++++++++-------- drivers/iommu/iommu.c | 3 ++- 2 files changed, 38 insertions(+), 9 deletions(-) diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig index 83664db5221df02..fe715fb295c6ed2 100644 --- a/drivers/iommu/Kconfig +++ b/drivers/iommu/Kconfig @@ -75,16 +75,44 @@ config IOMMU_DEBUGFS debug/iommu directory, and then populate a subdirectory with entries as required. -config IOMMU_DEFAULT_PASSTHROUGH - bool "IOMMU passthrough by default" +choice + prompt "IOMMU default DMA mode" depends on IOMMU_API - help - Enable passthrough by default, removing the need to pass in - iommu.passthrough=on or iommu=pt through command line. If this - is enabled, you can still disable with iommu.passthrough=off - or iommu=nopt depending on the architecture. + default IOMMU_DEFAULT_STRICT + help + This option allows an IOMMU DMA mode to be chosen at build time, to + override the default DMA mode of each ARCH, removing the need to + pass in kernel parameters through command line. You can still use + ARCH specific boot options to override this option again. - If unsure, say N here. + If unsure, keep the default. + +config IOMMU_DEFAULT_PASSTHROUGH + bool "passthrough" + help + In this mode, the DMA access through IOMMU without any addresses + translation. That means, the wrong or illegal DMA access can not + be caught, no error information will be reported. + +config IOMMU_DEFAULT_LAZY + bool "lazy" + help + Support lazy mode, where for every IOMMU DMA unmap operation, the + flush operation of IOTLB and the free operation of IOVA are deferred. + They are only guaranteed to be done before the related IOVA will be + reused. + +config IOMMU_DEFAULT_STRICT + bool "strict" + help + For every IOMMU DMA unmap operation, the flush operation of IOTLB and + the free operation of IOVA are guaranteed to be done in the unmap + function. + + This mode is safer than the two above, but it maybe slower in some + high performace scenarios. + +endchoice config OF_IOMMU def_bool y diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index f9cacce909d3ae9..05171dd0bd03aee 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -31,7 +31,8 @@ #else static unsigned int iommu_def_domain_type = IOMMU_DOMAIN_DMA; #endif -static bool iommu_dma_strict __read_mostly = true; +static bool iommu_dma_strict __read_mostly = + IS_ENABLED(CONFIG_IOMMU_DEFAULT_STRICT); struct iommu_group { struct kobject kobj; -- 1.8.3 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu