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 1790FCD6E4A for ; Thu, 4 Jun 2026 08:41:45 +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=3CiqjWgPjIETOFd/RHaVKoSJDsdZciSeCPQBjeeboj0=; b=dWGhMDUzcJfiZHTun4c+ZIwGb6 6SpKyg+l6j6EPKseUQGrEMSqatZbI67rVk4qYDCaKLg+Xl9ZgEOlC0PxDTqKxZs0GiNg/608na0wf epHDHdAZ+u+tJopd7CGew63P5lowgi9vnUQp9UzvN/oGsXXYsPLqqPNUXUzY5Udfh8boPE6PM9qZx B7QGSAaCErlHRVrhSIjTz6WOafnNk9aVY+K4fleWxFUvWAc5zW4p+w5bexKcelrWgseykAhIjoXMj AUzGs81sUVHarBX9Od0sIIbgLUbOC/s9+DYR1MWhpDDfi5aZ35vRj0DFBISMPujC01iD+oda2+fW2 Po5tnPlg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wV3dy-0000000GOdh-45m6; Thu, 04 Jun 2026 08:41:38 +0000 Received: from sea.source.kernel.org ([2600:3c0a:e001:78e:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wV3dx-0000000GOcg-0oQF for linux-arm-kernel@lists.infradead.org; Thu, 04 Jun 2026 08:41:37 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id E123C40E92; Thu, 4 Jun 2026 08:41:36 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 204E51F00898; Thu, 4 Jun 2026 08:41:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1780562496; bh=3CiqjWgPjIETOFd/RHaVKoSJDsdZciSeCPQBjeeboj0=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Xvdh0MQeJ/b/48NOUsnmuAsauPP0E6/ujqJYsTLG4sz/54ny/xrxp7VdtMBxRDDvJ Ud49deqI2YWvvZ6K0b4OOGEha2+OqCAboobMdaZ3ApmnNHeCLAVz7W56qPKsE7CCvg F/OsO3tIBsb0UkyEDnsmj/rcbZF0dVRP4syf8Iq7cEzw/EDtqcJCHtpyfeZ7G7+dou RCkeNRqWKGooUbundlUU9qj6HaVFahiRLHqgPuaY9ih2sghXuPzRAJTFW8OKsNDizx VZLV+T0MCQRjG/XVjuqLqcLaUZ+qalbzcKfEkSMo0JhFJnSiZyUdLsyRv2XEDHdK9q YkgH52QYueURg== 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 v6 09/20] dma-direct: make dma_direct_map_phys() honor DMA_ATTR_CC_SHARED Date: Thu, 4 Jun 2026 14:09:48 +0530 Message-ID: <20260604083959.1265923-10-aneesh.kumar@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260604083959.1265923-1-aneesh.kumar@kernel.org> References: <20260604083959.1265923-1-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 ad3c6d92b801..581af1483c42 100644 --- a/arch/s390/mm/init.c +++ b/arch/s390/mm/init.c @@ -163,7 +163,7 @@ 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 e4cba322386d..6d0ce3cfd8cc 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -702,8 +702,10 @@ 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