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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 42B02C43458 for ; Wed, 1 Jul 2026 05:52:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=/eHZDXBVbS1+y0J95IgLoHD6fsKY3hvUtozF7MkZe9w=; b=yjqCJtsjzuDx+8jxvUX4TVobX0 E0sGgOro5/R5zMOwX3KMtHzPZM5Xqnl2u7KJl7EM064PXRrRV8fHmWKz1rL40NflcjmUSDRaoSEWP l6d+PE5Jz3wISNW42LndqMEkkfejigKCj0gNFPb7M7jvyt3xTTC1qeU65BJt/UAORZ0LAQ5tekGrz nx/hNQbrPGJf2cJ11w0O4HVvGWfbeFegzxsWQfD9ePs/QpVFhsGXszDnfQlPgtYMfpQI3sLTdNiWd /6JpS5ElVzRh26jkmRQAcKFtjVxqUOh5OYF1+4nsSncfZzbNr4vxX6+J0P2u1Um816Pkx/vNAPRPQ O+kXAEhg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wensI-00000000jGh-2Zxc; Wed, 01 Jul 2026 05:52:42 +0000 Received: from tor.source.kernel.org ([2600:3c04:e001:324:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wensH-00000000jFU-1nwW for linux-arm-kernel@lists.infradead.org; Wed, 01 Jul 2026 05:52:41 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id C15D0601D6; Wed, 1 Jul 2026 05:52:40 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0DF651F00A3A; Wed, 1 Jul 2026 05:52:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782885160; bh=/eHZDXBVbS1+y0J95IgLoHD6fsKY3hvUtozF7MkZe9w=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=B6IhXtaavaaZGDnsfd9lZUOz4LB2/SXHL3ZdBkRu6jsQ6Y3inpT2xdRLJQHpC0Bs2 mn8neJ0rZylTjhxtbYulflsvKDf3+04qJ++XC7fIy181GSrJhyLujNzzgAYNru7VnU /01MAjBbx16bGwBsw6rSyrEtNPMoE4pOYFK10aWimNqUKLOux72JWd/z8mEfeV+r/9 htZDa6GdW86gR6uK4KdKx71HtZeOSwwAsnzHHByWxjLOJ1uhHYMYdj7rA/7m9Yf8Qt wUOeixxWbP74hN9kT8P/ODQ2r8DdS+uEMcJSpUeh8gyvTqzOAeUHJA+5+U3csHRxWJ 5xJZv8VqPiYLw== From: "Aneesh Kumar K.V (Arm)" To: iommu@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-coco@lists.linux.dev Cc: "Aneesh Kumar K.V (Arm)" , Robin Murphy , Marek Szyprowski , Will Deacon , Marc Zyngier , Steven Price , Suzuki K Poulose , Catalin Marinas , Jiri Pirko , Jason Gunthorpe , Mostafa Saleh , Petr Tesarik , Alexey Kardashevskiy , Dan Williams , Xu Yilun , linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , "Christophe Leroy (CS GROUP)" , Alexander Gordeev , Gerald Schaefer , Heiko Carstens , Vasily Gorbik , Christian Borntraeger , Sven Schnelle , x86@kernel.org, Jiri Pirko , Michael Kelley Subject: [PATCH v7 16/22] dma-direct: make dma_direct_map_phys() honor DMA_ATTR_CC_SHARED Date: Wed, 1 Jul 2026 11:19:20 +0530 Message-ID: <20260701054926.825925-17-aneesh.kumar@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260701054926.825925-1-aneesh.kumar@kernel.org> References: <20260701054926.825925-1-aneesh.kumar@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Teach dma_direct_map_phys() to select the DMA address encoding based on DMA_ATTR_CC_SHARED. Use phys_to_dma_unencrypted() for decrypted mappings and phys_to_dma_encrypted() otherwise. If a device requires unencrypted DMA but the source physical address is still encrypted, force the mapping through swiotlb so the DMA address and backing memory attributes remain consistent. Update the arm64, x86, s390 and powerpc secure-guest setup to not use swiotlb force option Tested-by: Jiri Pirko Tested-by: Michael Kelley Tested-by: Mostafa Saleh Signed-off-by: Aneesh Kumar K.V (Arm) --- Changes from v3: * Handle DMA_ATTR_MMIO --- arch/arm64/mm/init.c | 4 +-- arch/powerpc/platforms/pseries/svm.c | 2 +- arch/s390/mm/init.c | 2 +- arch/x86/kernel/pci-dma.c | 4 +-- kernel/dma/direct.c | 4 ++- kernel/dma/direct.h | 45 +++++++++++++++------------- 6 files changed, 31 insertions(+), 30 deletions(-) diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index 97987f850a33..acf67c7064db 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -338,10 +338,8 @@ void __init arch_mm_preinit(void) unsigned int flags = SWIOTLB_VERBOSE; bool swiotlb = max_pfn > PFN_DOWN(arm64_dma_phys_limit); - if (is_realm_world()) { + if (is_realm_world()) swiotlb = true; - flags |= SWIOTLB_FORCE; - } if (IS_ENABLED(CONFIG_DMA_BOUNCE_UNALIGNED_KMALLOC) && !swiotlb) { /* diff --git a/arch/powerpc/platforms/pseries/svm.c b/arch/powerpc/platforms/pseries/svm.c index 384c9dc1899a..7a403dbd35ee 100644 --- a/arch/powerpc/platforms/pseries/svm.c +++ b/arch/powerpc/platforms/pseries/svm.c @@ -29,7 +29,7 @@ static int __init init_svm(void) * need to use the SWIOTLB buffer for DMA even if dma_capable() says * otherwise. */ - ppc_swiotlb_flags |= SWIOTLB_ANY | SWIOTLB_FORCE; + ppc_swiotlb_flags |= SWIOTLB_ANY; /* Share the SWIOTLB buffer with the host. */ swiotlb_update_mem_attributes(); diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c index 6b1c5a4fa9ce..8d1de5a2e554 100644 --- a/arch/s390/mm/init.c +++ b/arch/s390/mm/init.c @@ -166,7 +166,7 @@ static void __init pv_init(void) virtio_set_mem_acc_cb(virtio_require_restricted_mem_acc); /* make sure bounce buffers are shared */ - swiotlb_init(true, SWIOTLB_FORCE | SWIOTLB_VERBOSE); + swiotlb_init(true, SWIOTLB_VERBOSE); swiotlb_update_mem_attributes(); } diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c index 6267363e0189..75cf8f6ae8cd 100644 --- a/arch/x86/kernel/pci-dma.c +++ b/arch/x86/kernel/pci-dma.c @@ -59,10 +59,8 @@ static void __init pci_swiotlb_detect(void) * bounce buffers as the hypervisor can't access arbitrary VM memory * that is not explicitly shared with it. */ - if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) { + if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) x86_swiotlb_enable = true; - x86_swiotlb_flags |= SWIOTLB_FORCE; - } } #else static inline void __init pci_swiotlb_detect(void) diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 9935f7caa459..edf40746a775 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -693,8 +693,10 @@ size_t dma_direct_max_mapping_size(struct device *dev) { /* If SWIOTLB is active, use its maximum mapping size */ if (is_swiotlb_active(dev) && - (dma_addressing_limited(dev) || is_swiotlb_force_bounce(dev))) + (dma_addressing_limited(dev) || is_swiotlb_force_bounce(dev) || + force_dma_unencrypted(dev))) return swiotlb_max_mapping_size(dev); + return SIZE_MAX; } diff --git a/kernel/dma/direct.h b/kernel/dma/direct.h index e05dc7649366..f3fc28f352ba 100644 --- a/kernel/dma/direct.h +++ b/kernel/dma/direct.h @@ -88,37 +88,40 @@ static inline dma_addr_t dma_direct_map_phys(struct device *dev, { dma_addr_t dma_addr; + /* + * For a device requiring unencrypted DMA, MMIO memory is treated + * as shared by default. + */ + if (force_dma_unencrypted(dev) && (attrs & DMA_ATTR_MMIO)) + attrs |= DMA_ATTR_CC_SHARED; + if (is_swiotlb_force_bounce(dev)) { - if (!(attrs & DMA_ATTR_CC_SHARED)) { - if (attrs & (DMA_ATTR_MMIO | DMA_ATTR_REQUIRE_COHERENT)) - return DMA_MAPPING_ERROR; + if (attrs & (DMA_ATTR_MMIO | DMA_ATTR_REQUIRE_COHERENT)) + return DMA_MAPPING_ERROR; - return swiotlb_map(dev, phys, size, dir, attrs); - } - } else if (attrs & DMA_ATTR_CC_SHARED) { - return DMA_MAPPING_ERROR; + return swiotlb_map(dev, phys, size, dir, attrs); } - if (attrs & DMA_ATTR_MMIO) { - dma_addr = phys; - if (unlikely(!dma_capable(dev, dma_addr, size, false, attrs))) - goto err_overflow; - } else if (attrs & DMA_ATTR_CC_SHARED) { + if (attrs & DMA_ATTR_CC_SHARED) dma_addr = phys_to_dma_unencrypted(dev, phys); + else + dma_addr = phys_to_dma_encrypted(dev, phys); + + if (attrs & DMA_ATTR_MMIO) { if (unlikely(!dma_capable(dev, dma_addr, size, false, attrs))) goto err_overflow; - } else { - dma_addr = phys_to_dma(dev, phys); - if (unlikely(!dma_capable(dev, dma_addr, size, true, attrs)) || - dma_kmalloc_needs_bounce(dev, size, dir)) { - if (is_swiotlb_active(dev) && - !(attrs & DMA_ATTR_REQUIRE_COHERENT)) - return swiotlb_map(dev, phys, size, dir, attrs); + goto dma_mapped; + } - goto err_overflow; - } + if (unlikely(!dma_capable(dev, dma_addr, size, true, attrs)) || + dma_kmalloc_needs_bounce(dev, size, dir)) { + if (is_swiotlb_active(dev) && + !(attrs & DMA_ATTR_REQUIRE_COHERENT)) + return swiotlb_map(dev, phys, size, dir, attrs); + goto err_overflow; } +dma_mapped: if (!dev_is_dma_coherent(dev) && !(attrs & (DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_MMIO))) { arch_sync_dma_for_device(phys, size, dir); -- 2.43.0