From patchwork Thu Sep 21 07:54:20 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yi Liu X-Patchwork-Id: 13394371 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A1B7AE7D0A8 for ; Thu, 21 Sep 2023 19:28:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230414AbjIUT2k (ORCPT ); Thu, 21 Sep 2023 15:28:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43708 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230412AbjIUT2Z (ORCPT ); Thu, 21 Sep 2023 15:28:25 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.20]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4990576B6; Thu, 21 Sep 2023 10:10:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1695316220; x=1726852220; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=X9BBfgk8l9qrBPqgGMYev0KIhH/OZFgWEJbj0DqM7ps=; b=aQOyF2nRK+tn5jfi9VgKf5gncIlneS1E5shoEImI3P8xl+Ox9gECyWTm 5RfYqOD/gbxVRzS8hXF7RY9DArGFgs9HKqbMMcaauWJN6uiPHmWCo3tqZ wQzKOZwCU28scH2FDR+QVpGwNmDX2KMBT5D6rBv2DRtsLx0YWzCZt6xoC r2mOGlge/GNDLCS9vcONkJjVxlvXP8T59OaTpJSZg1BA1PWwrgeFzq2QK 2qTaGRmCXcCM/xdnPm/ko4JB/8wo5LGC9Xp4e0bTDB8HOxImIDc/SN7GI nUNqVhYXtAwos0/9Eh0jkuh3FOFEDFvFysZk3spEYt23FG/eZUt+bm42r Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10839"; a="370764359" X-IronPort-AV: E=Sophos;i="6.03,164,1694761200"; d="scan'208";a="370764359" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Sep 2023 00:54:43 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10839"; a="812522971" X-IronPort-AV: E=Sophos;i="6.03,164,1694761200"; d="scan'208";a="812522971" Received: from 984fee00a4c6.jf.intel.com ([10.165.58.231]) by fmsmga008.fm.intel.com with ESMTP; 21 Sep 2023 00:54:42 -0700 From: Yi Liu To: joro@8bytes.org, alex.williamson@redhat.com, jgg@nvidia.com, kevin.tian@intel.com, robin.murphy@arm.com, baolu.lu@linux.intel.com Cc: cohuck@redhat.com, eric.auger@redhat.com, nicolinc@nvidia.com, kvm@vger.kernel.org, mjrosato@linux.ibm.com, chao.p.peng@linux.intel.com, yi.l.liu@intel.com, yi.y.sun@linux.intel.com, peterx@redhat.com, jasowang@redhat.com, shameerali.kolothum.thodi@huawei.com, lulu@redhat.com, suravee.suthikulpanit@amd.com, iommu@lists.linux.dev, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, zhenzhong.duan@intel.com, joao.m.martins@oracle.com Subject: [PATCH v5 00/11] Add Intel VT-d nested translation Date: Thu, 21 Sep 2023 00:54:20 -0700 Message-Id: <20230921075431.125239-1-yi.l.liu@intel.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org This is to add Intel VT-d nested translation based on IOMMUFD nesting infrastructure. As the iommufd nesting infrastructure series[1], iommu core supports new ops to report iommu hardware information, allocate domains with user data and invalidate stage-1 IOTLB when there is mapping changed in stage-1 page table. The data required in the three paths are vendor-specific, so 1) IOMMU_HWPT_TYPE_VTD_S1 is defined for the Intel VT-d stage-1 page table, it will be used in the stage-1 domain allocation and IOTLB syncing path. struct iommu_hwpt_vtd_s1 is defined to pass user_data for the Intel VT-d stage-1 domain allocation. struct iommu_hwpt_vtd_s1_invalidate is defined to pass the data for the Intel VT-d stage-1 IOTLB invalidation. 2) IOMMU_HW_INFO_TYPE_INTEL_VTD and struct iommu_hw_info_vtd are defined to report iommu hardware information for Intel VT-d. With above IOMMUFD extensions, the intel iommu driver implements the three paths to support nested translation. The first Intel platform supporting nested translation is Sapphire Rapids which, unfortunately, has a hardware errata [2] requiring special treatment. This errata happens when a stage-1 page table page (either level) is located in a stage-2 read-only region. In that case the IOMMU hardware may ignore the stage-2 RO permission and still set the A/D bit in stage-1 page table entries during page table walking. A flag IOMMU_HW_INFO_VTD_ERRATA_772415_SPR17 is introduced to report this errata to userspace. With that restriction the user should either disable nested translation to favor RO stage-2 mappings or ensure no RO stage-2 mapping to enable nested translation. Intel-iommu driver is armed with necessary checks to prevent such mix in patch12 of this series. Qemu currently does add RO mappings though. The vfio agent in Qemu simply maps all valid regions in the GPA address space which certainly includes RO regions e.g. vbios. In reality we don't know a usage relying on DMA reads from the BIOS region. Hence finding a way to skip RO regions (e.g. via a discard manager) in Qemu might be an acceptable tradeoff. The actual change needs more discussion in Qemu community. For now we just hacked Qemu to test. Complete code can be found in [3], corresponding QEMU could can be found in [4]. [1] https://lore.kernel.org/linux-iommu/20230921075138.124099-1-yi.l.liu@intel.com/ [2] https://www.intel.com/content/www/us/en/content-details/772415/content-details.html [3] https://github.com/yiliu1765/iommufd/tree/iommufd_nesting [4] https://github.com/yiliu1765/qemu/tree/zhenzhong/wip/iommufd_nesting_rfcv1 Change log: v5: - Add Kevin's r-b for patch 2, 3 ,5 8, 10 - Drop enforce_cache_coherency callback from the nested type domain ops (Kevin) - Remove duplicate agaw check in patch 04 (Kevin) - Remove duplicate domain_update_iommu_cap() in patch 06 (Kevin) - Check parent's force_snooping to set pgsnp in the pasid entry (Kevin) - uapi data structure check (Kevin) - Simplify the errata handling as user can allocate nested parent domain v4: https://lore.kernel.org/linux-iommu/20230724111335.107427-1-yi.l.liu@intel.com/ - Remove ascii art tables (Jason) - Drop EMT (Tina, Jason) - Drop MTS and related definitions (Kevin) - Rename macro IOMMU_VTD_PGTBL_ to IOMMU_VTD_S1_ (Kevin) - Rename struct iommu_hwpt_intel_vtd_ to iommu_hwpt_vtd_ (Kevin) - Rename struct iommu_hwpt_intel_vtd to iommu_hwpt_vtd_s1 (Kevin) - Put the vendor specific hwpt alloc data structure before enuma iommu_hwpt_type (Kevin) - Do not trim the higher page levels of S2 domain in nested domain attachment as the S2 domain may have been used independently. (Kevin) - Remove the first-stage pgd check against the maximum address of s2_domain as hw can check it anyhow. It makes sense to check every pfns used in the stage-1 page table. But it cannot make it. So just leave it to hw. (Kevin) - Split the iotlb flush part into an order of uapi, helper and callback implementation (Kevin) - Change the policy of VT-d nesting errata, disallow RO mapping once a domain is used as parent domain of a nested domain. This removes the nested_users counting. (Kevin) - Minor fix for "make htmldocs" v3: https://lore.kernel.org/linux-iommu/20230511145110.27707-1-yi.l.liu@intel.com/ - Further split the patches into an order of adding helpers for nested domain, iotlb flush, nested domain attachment and nested domain allocation callback, then report the hw_info to userspace. - Add batch support in cache invalidation from userspace - Disallow nested translation usage if RO mappings exists in stage-2 domain due to errata on readonly mappings on Sapphire Rapids platform. v2: https://lore.kernel.org/linux-iommu/20230309082207.612346-1-yi.l.liu@intel.com/ - The iommufd infrastructure is split to be separate series. v1: https://lore.kernel.org/linux-iommu/20230209043153.14964-1-yi.l.liu@intel.com/ Regards, Yi Liu Lu Baolu (5): iommu/vt-d: Extend dmar_domain to support nested domain iommu/vt-d: Add helper for nested domain allocation iommu/vt-d: Add helper to setup pasid nested translation iommu/vt-d: Add nested domain allocation iommu/vt-d: Disallow read-only mappings to nest parent domain Yi Liu (6): iommufd: Add data structure for Intel VT-d stage-1 domain allocation iommu/vt-d: Make domain attach helpers to be extern iommu/vt-d: Set the nested domain to a device iommufd: Add data structure for Intel VT-d stage-1 cache invalidation iommu/vt-d: Make iotlb flush helpers to be extern iommu/vt-d: Add iotlb flush for nested domain drivers/iommu/intel/Makefile | 2 +- drivers/iommu/intel/iommu.c | 60 +++++++++---- drivers/iommu/intel/iommu.h | 51 +++++++++-- drivers/iommu/intel/nested.c | 162 +++++++++++++++++++++++++++++++++++ drivers/iommu/intel/pasid.c | 125 +++++++++++++++++++++++++++ drivers/iommu/intel/pasid.h | 2 + include/uapi/linux/iommufd.h | 76 +++++++++++++++- 7 files changed, 452 insertions(+), 26 deletions(-) create mode 100644 drivers/iommu/intel/nested.c