From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 95CE13A640C; Tue, 12 May 2026 09:04:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778576671; cv=none; b=G+YQdgdZZWP/x1l3nj0hFA9j15XDp30iw1E5nJWhvVI8HZq1ZSGevY56PX0RA4KVnsuafDjPXw2NzaJ9nBhTu7Z97q67tm5aru7fmaYGaCA8TLlconE9uTP5Y0OC6f0PTGmzFXasewBPkMQ6i6bpxVUJvtzeuepzTXgOsJ9wyHo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778576671; c=relaxed/simple; bh=61tXliQ/XBJoYkUBUBG8gxT+9Bu+8tJYiCkn9FV4ylo=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=WonR/d9DcV0LG0oVdg3x73lSn1HtmYCx9zqYd/bW6+lOMUbhcFFDSLaYcyr1pJEVan/Y5ruPx8rMdFGpzBcq0n6EpEMzEDXch9LjWvh2czNdlpD+BUUqDVFKPyzMczkP0CjCF9tvgmM/Ds3Ci04nG2Z4SL/C9UJTJ9p3BG9EZ6A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=oJTobraK; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="oJTobraK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DB5B7C2BCC7; Tue, 12 May 2026 09:04:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1778576671; bh=61tXliQ/XBJoYkUBUBG8gxT+9Bu+8tJYiCkn9FV4ylo=; h=From:To:Cc:Subject:Date:From; b=oJTobraKOVigupVmeMOO2+Q1wWOaVGKhX/GzhO1CR+oMrH2HI51YYrr008C537v+G UUVmRUhwCUoGaExJMCFAz+hSb3R4HWDxAxNODc6Y4bmdjdIXAVj78RFh9mwRcqVLgb Fx8/aKJ77PvgASKN7hafTS/YFqKFOGxS5qXl95RkVPeuKoTEH3cP7zNJjuPaMUb+gZ V0V/jF3o7H6NpExI8piAPfpZwpG6PjdGI1VEOZLtFahXamXt2PkTVP2U5Iv1vt/4b8 kqZmwZ86YGl97t8WiCSsqraIBEIvzUK06TVDfB50pvAxePXnFWAsKttcJ5wH4cvaYs OSuujN6V1HRVQ== 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 Subject: [PATCH v4 00/13] dma-mapping: Use DMA_ATTR_CC_SHARED through direct, pool and swiotlb paths Date: Tue, 12 May 2026 14:33:55 +0530 Message-ID: <20260512090408.794195-1-aneesh.kumar@kernel.org> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-s390@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit This series propagates DMA_ATTR_CC_SHARED through the dma-direct, dma-pool, and swiotlb paths so that encrypted and decrypted DMA buffers are handled consistently. Today, the direct DMA path mostly relies on force_dma_unencrypted() for shared/decrypted buffer handling. This series consolidates the force_dma_unencrypted() checks in the top-level functions and ensures that the remaining DMA interfaces use DMA attributes to make the correct decisions. The series: - moves swiotlb-backed allocations out of __dma_direct_alloc_pages(), - propagates DMA_ATTR_CC_SHARED through the dma-direct alloc/free paths - teaches the atomic DMA pools to track encrypted versus decrypted state - tracks swiotlb pool encryption state and enforces strict pool selection - centralizes encrypted/decrypted pgprot handling in dma_pgprot() using DMA attributes - passes DMA attributes down to dma_capable() so capability checks can validate whether the selected DMA address encoding matches DMA_ATTR_CC_SHARED - makes dma_direct_map_phys() choose the DMA address encoding from DMA_ATTR_CC_SHARED and fall back to swiotlb when a shared DMA request cannot use the direct mapping, which lets arm64 and x86 CCA guests stop relying on SWIOTLB_FORCE for DMA mappings - use the selected swiotlb pool state to derive the returned DMA address. Changes from v3: https://lore.kernel.org/all/20260427055509.898190-1-aneesh.kumar@kernel.org * Handle DMA_ATTR_MMIO correctly in dma_direct_map_phys() * Address most of sashiko review * Rebase to latest kernel * drop SWIOTLB_FORCE for s390 and powerpc secure guest. Changes from v2: https://lore.kernel.org/all/20260420061415.3650870-1-aneesh.kumar@kernel.org * pass attrs to dma_capable() and update direct, swiotlb, Xen swiotlb, and x86 GART paths so the capability checks see the DMA address attr value DMA_ATTR_CC_SHARED. * rework dma_direct_map_phys() so DMA_ATTR_CC_SHARED selects phys_to_dma_unencrypted() while the default path uses phys_to_dma_encrypted(), with swiotlb fallback when the requested shared/private state cannot be satisfied by a direct DMA address. * stop relying on SWIOTLB_FORCE for arm64 and x86 CC guest DMA mappings; swiotlb is still enabled there, but shared mappings is now selected through the generic dma_direct_map_phys()/dma_capable() decision instead of a global force-bounce flag. Changes from v1: https://lore.kernel.org/all/20260417085900.3062416-1-aneesh.kumar@kernel.org * rebased to latest kernel (change from DMA_ATTR_CC_DECRYPTED -> DMA_ATTR_CC_SHARED) * update the alloc path so DMA_ATTR_CC_SHARED is not a caller-visible attribute. Cc: Robin Murphy Cc: Marek Szyprowski Cc: Will Deacon Cc: Marc Zyngier Cc: Steven Price Cc: Suzuki K Poulose Cc: Catalin Marinas Cc: Jiri Pirko Cc: Jason Gunthorpe Cc: Mostafa Saleh Cc: Petr Tesarik Cc: Alexey Kardashevskiy Cc: Dan Williams Cc: Xu Yilun Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-s390@vger.kernel.org Cc: Madhavan Srinivasan Cc: Michael Ellerman Cc: Nicholas Piggin Cc: "Christophe Leroy (CS GROUP)" Cc: Alexander Gordeev Cc: Gerald Schaefer Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Christian Borntraeger Cc: Sven Schnelle Cc: x86@kernel.org Aneesh Kumar K.V (Arm) (13): dma-direct: swiotlb: handle swiotlb alloc/free outside __dma_direct_alloc_pages dma-direct: use DMA_ATTR_CC_SHARED in alloc/free paths dma-pool: track decrypted atomic pools and select them via attrs dma: swiotlb: track pool encryption state and honor DMA_ATTR_CC_SHARED dma-mapping: make dma_pgprot() honor DMA_ATTR_CC_SHARED dma-direct: pass attrs to dma_capable() for DMA_ATTR_CC_SHARED checks dma-direct: make dma_direct_map_phys() honor DMA_ATTR_CC_SHARED dma-direct: set decrypted flag for remapped DMA allocations dma-direct: select DMA address encoding from DMA_ATTR_CC_SHARED dma-pool: fix page leak in atomic_pool_expand() cleanup dma-direct: rename ret to cpu_addr in alloc helpers dma-direct: return struct page from dma_direct_alloc_from_pool() x86/amd-gart: preserve the direct DMA address until GART mapping succeeds arch/arm64/mm/init.c | 4 +- arch/powerpc/platforms/pseries/svm.c | 2 +- arch/s390/mm/init.c | 2 +- arch/x86/kernel/amd_gart_64.c | 36 ++-- arch/x86/kernel/pci-dma.c | 4 +- drivers/iommu/dma-iommu.c | 2 +- drivers/xen/swiotlb-xen.c | 10 +- include/linux/dma-direct.h | 19 ++- include/linux/dma-map-ops.h | 2 +- include/linux/swiotlb.h | 8 +- kernel/dma/direct.c | 243 ++++++++++++++++++++------- kernel/dma/direct.h | 40 ++--- kernel/dma/mapping.c | 16 +- kernel/dma/pool.c | 165 +++++++++++------- kernel/dma/swiotlb.c | 109 +++++++++--- 15 files changed, 459 insertions(+), 203 deletions(-) base-commit: 50897c955902c93ae71c38698abb910525ebdc89 -- 2.43.0