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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 3AA45C43381 for ; Wed, 27 Mar 2019 15:01:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 08D232082F for ; Wed, 27 Mar 2019 15:01:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728761AbfC0PBt (ORCPT ); Wed, 27 Mar 2019 11:01:49 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:5195 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728133AbfC0PBt (ORCPT ); Wed, 27 Mar 2019 11:01:49 -0400 Received: from DGGEMS401-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id 76FD69C447E6CE066E30; Wed, 27 Mar 2019 23:01:38 +0800 (CST) Received: from HGHY1l002753561.china.huawei.com (10.177.23.164) by DGGEMS401-HUB.china.huawei.com (10.3.19.201) with Microsoft SMTP Server id 14.3.408.0; Wed, 27 Mar 2019 23:01:32 +0800 From: Zhen Lei To: Jean-Philippe Brucker , John Garry , Robin Murphy , Will Deacon , Joerg Roedel , iommu , linux-kernel CC: Zhen Lei , Hanjun Guo Subject: [PATCH v2 1/1] iommu: Add config option to set lazy mode as default Date: Wed, 27 Mar 2019 23:00:30 +0800 Message-ID: <20190327150030.11112-1-thunder.leizhen@huawei.com> X-Mailer: git-send-email 2.19.2.windows.1 MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.177.23.164] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This allows the default behaviour to be controlled by a kernel config option instead of changing the command line for the kernel to include "iommu.strict=0" on ARM64 where this is desired. This is similar to CONFIG_IOMMU_DEFAULT_PASSTHROUGH. Note: At present, intel_iommu, amd_iommu and s390_iommu use lazy mode as default, so there is no need to add code for them. Signed-off-by: Zhen Lei --- drivers/iommu/Kconfig | 14 ++++++++++++++ drivers/iommu/iommu.c | 5 +++++ 2 files changed, 19 insertions(+) diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig index 6f07f3b21816c64..5daa110d0e83a07 100644 --- a/drivers/iommu/Kconfig +++ b/drivers/iommu/Kconfig @@ -85,6 +85,20 @@ config IOMMU_DEFAULT_PASSTHROUGH If unsure, say N here. +config IOMMU_DMA_DEFAULT_LAZY_MODE + bool "IOMMU DMA use lazy mode to flush IOTLB and free IOVA" + depends on IOMMU_API + 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. Removing the need to pass in kernel parameters through + command line. For example, iommu.strict=0 on ARM64. If this is + enabled, you can still disable with kernel parameters, such as + iommu.strict=1 depending on the architecture. + + If unsure, say N here. + config OF_IOMMU def_bool y depends on OF && IOMMU_API diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 33a982e33716369..5acb98e79b5b32d 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -43,7 +43,12 @@ #else static unsigned int iommu_def_domain_type = IOMMU_DOMAIN_DMA; #endif + +#ifdef CONFIG_IOMMU_DMA_DEFAULT_LAZY_MODE +static bool iommu_dma_strict __read_mostly; +#else static bool iommu_dma_strict __read_mostly = true; +#endif struct iommu_callback_data { const struct iommu_ops *ops; -- 1.8.3