From patchwork Tue Dec 7 07:55:59 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tianyu Lan X-Patchwork-Id: 12661235 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 37A08C433FE for ; Tue, 7 Dec 2021 07:56:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231801AbhLGH7m (ORCPT ); Tue, 7 Dec 2021 02:59:42 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35956 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231744AbhLGH7i (ORCPT ); Tue, 7 Dec 2021 02:59:38 -0500 Received: from mail-pl1-x62f.google.com (mail-pl1-x62f.google.com [IPv6:2607:f8b0:4864:20::62f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B81A6C061748; Mon, 6 Dec 2021 23:56:08 -0800 (PST) Received: by mail-pl1-x62f.google.com with SMTP id m24so8834889pls.10; Mon, 06 Dec 2021 23:56:08 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=FlswnO/0tf48MZik9N6nEWD7pUN7KQPdPDwLH82NPGY=; b=M6j32vO6y0Cf9pIbKk39JuYSB6qhiA4ISG+dC2eWbE8WlbOn05EyJlJOHMZbN4sPYL ws48Y7/7tQPMzGEcFkLCvq20zNLGMYKX11QmGZkKICvu7FCQPDKbnQkxEsM7u5+LSbPU Uhc/zLWPzsLSBAK9oZ4860ZdDzDSYjSImY45j82WSo5UW2erMspe+79I1DPMCeMJ1Mxu SPFc+yvxtdlgSbA+pxhCMF/TRXiJfMMy+yLwSbyAE97P8sxA1TBuimZR+OOQgVQm4/mP Cn9RxEnq30tuwnxcQdSK6jJz3Wp2HQGYga5dr7s3w4LWOLN4aWJUqT4SKOJMoPvjZOLC trBA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=FlswnO/0tf48MZik9N6nEWD7pUN7KQPdPDwLH82NPGY=; b=jKrBaHrQk/3xonSW3YwLddXodPzinGCdTFjnYCj/m/9PYPV/KZCSVROTbNTdxll/i4 o2YzEcgEfVzQ2I/JR5k2iul+hkgP++dadv4B0DaNNMHZ8PFWqKafTrUI38XaAowDzHRZ j77Cq9R9wOtl4CtQBvXBc0i4wHXAWLEz7bhGuJoVWuux3qT8NtQNlsocDsgnAZcVa9+Q XVz7bSJpAblzSqfet8Po8rZxZT+tIbDxzzQzRkdCcLzQA5Sb62ixrtVrgi38Z2J6t/TX GLsikTVU93DloXzQJpqKdhz5SnXOxGpmpfVxyFzJu7zfWaABnhxiwgT2es3ry2ZoNOZl 84MQ== X-Gm-Message-State: AOAM530QQyME0RhBPjmHrxU89iSwbhfgkeQ686UiZbumxFcVzMkFAyfJ Rv8GWqWcQ1Dyyaem5yoCags= X-Google-Smtp-Source: ABdhPJxiP/HZc+wU1245UxqyTwDjh+Ent9STMh0ZoLxlwQ6RErKujVLQVg8ZxHfyFD1BbCobFzYW0g== X-Received: by 2002:a17:90b:1c06:: with SMTP id oc6mr4725473pjb.126.1638863768311; Mon, 06 Dec 2021 23:56:08 -0800 (PST) Received: from ubuntu-Virtual-Machine.corp.microsoft.com ([2001:4898:80e8:0:a463:d753:723:c3a9]) by smtp.gmail.com with ESMTPSA id n15sm1794353pgs.59.2021.12.06.23.56.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 06 Dec 2021 23:56:08 -0800 (PST) From: Tianyu Lan To: kys@microsoft.com, haiyangz@microsoft.com, sthemmin@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, davem@davemloft.net, kuba@kernel.org, jejb@linux.ibm.com, martin.petersen@oracle.com, arnd@arndb.de, hch@infradead.org, m.szyprowski@samsung.com, robin.murphy@arm.com, Tianyu.Lan@microsoft.com, thomas.lendacky@amd.com, michael.h.kelley@microsoft.com Cc: iommu@lists.linux-foundation.org, linux-arch@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org, netdev@vger.kernel.org, vkuznets@redhat.com, brijesh.singh@amd.com, konrad.wilk@oracle.com, hch@lst.de, joro@8bytes.org, parri.andrea@gmail.com, dave.hansen@intel.com Subject: [PATCH V6 3/5] hyper-v: Enable swiotlb bounce buffer for Isolation VM Date: Tue, 7 Dec 2021 02:55:59 -0500 Message-Id: <20211207075602.2452-4-ltykernel@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20211207075602.2452-1-ltykernel@gmail.com> References: <20211207075602.2452-1-ltykernel@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Tianyu Lan hyperv Isolation VM requires bounce buffer support to copy data from/to encrypted memory and so enable swiotlb force mode to use swiotlb bounce buffer for DMA transaction. In Isolation VM with AMD SEV, the bounce buffer needs to be accessed via extra address space which is above shared_gpa_boundary (E.G 39 bit address line) reported by Hyper-V CPUID ISOLATION_CONFIG. The access physical address will be original physical address + shared_gpa_boundary. The shared_gpa_boundary in the AMD SEV SNP spec is called virtual top of memory(vTOM). Memory addresses below vTOM are automatically treated as private while memory above vTOM is treated as shared. Swiotlb bounce buffer code calls set_memory_decrypted() to mark bounce buffer visible to host and map it in extra address space via memremap. Populate the shared_gpa_boundary (vTOM) via swiotlb_unencrypted_base variable. The map function memremap() can't work in the early place (e.g ms_hyperv_init_platform()) and so call swiotlb_update_mem_ attributes() in the hyperv_init(). Signed-off-by: Tianyu Lan --- Change since v4: * Remove Hyper-V IOMMU IOMMU_INIT_FINISH related functions and set SWIOTLB_FORCE and swiotlb_unencrypted_base in the ms_hyperv_init_platform(). Call swiotlb_update_mem_attributes() in the hyperv_init(). Change since v3: * Add comment in pci-swiotlb-xen.c to explain why add dependency between hyperv_swiotlb_detect() and pci_ xen_swiotlb_detect(). * Return directly when fails to allocate Hyper-V swiotlb buffer in the hyperv_iommu_swiotlb_init(). --- arch/x86/hyperv/hv_init.c | 10 ++++++++++ arch/x86/kernel/cpu/mshyperv.c | 11 ++++++++++- include/linux/hyperv.h | 8 ++++++++ 3 files changed, 28 insertions(+), 1 deletion(-) diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c index 24f4a06ac46a..9e18a280f89d 100644 --- a/arch/x86/hyperv/hv_init.c +++ b/arch/x86/hyperv/hv_init.c @@ -28,6 +28,7 @@ #include #include #include +#include int hyperv_init_cpuhp; u64 hv_current_partition_id = ~0ull; @@ -502,6 +503,15 @@ void __init hyperv_init(void) /* Query the VMs extended capability once, so that it can be cached. */ hv_query_ext_cap(0); + + /* + * Swiotlb bounce buffer needs to be mapped in extra address + * space. Map function doesn't work in the early place and so + * call swiotlb_update_mem_attributes() here. + */ + if (hv_is_isolation_supported()) + swiotlb_update_mem_attributes(); + return; clean_guest_os_id: diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c index 4794b716ec79..baf3a0873552 100644 --- a/arch/x86/kernel/cpu/mshyperv.c +++ b/arch/x86/kernel/cpu/mshyperv.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include #include @@ -319,8 +320,16 @@ static void __init ms_hyperv_init_platform(void) pr_info("Hyper-V: Isolation Config: Group A 0x%x, Group B 0x%x\n", ms_hyperv.isolation_config_a, ms_hyperv.isolation_config_b); - if (hv_get_isolation_type() == HV_ISOLATION_TYPE_SNP) + if (hv_get_isolation_type() == HV_ISOLATION_TYPE_SNP) { static_branch_enable(&isolation_type_snp); + swiotlb_unencrypted_base = ms_hyperv.shared_gpa_boundary; + } + + /* + * Enable swiotlb force mode in Isolation VM to + * use swiotlb bounce buffer for dma transaction. + */ + swiotlb_force = SWIOTLB_FORCE; } if (hv_max_functions_eax >= HYPERV_CPUID_NESTED_FEATURES) { diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h index b823311eac79..1f037e114dc8 100644 --- a/include/linux/hyperv.h +++ b/include/linux/hyperv.h @@ -1726,6 +1726,14 @@ int hyperv_write_cfg_blk(struct pci_dev *dev, void *buf, unsigned int len, int hyperv_reg_block_invalidate(struct pci_dev *dev, void *context, void (*block_invalidate)(void *context, u64 block_mask)); +#if IS_ENABLED(CONFIG_HYPERV) +int __init hyperv_swiotlb_detect(void); +#else +static inline int __init hyperv_swiotlb_detect(void) +{ + return 0; +} +#endif struct hyperv_pci_block_ops { int (*read_block)(struct pci_dev *dev, void *buf, unsigned int buf_len,