From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 20107279DCA; Wed, 1 Jul 2026 05:51:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782885095; cv=none; b=GJNO6UO/T2iBiYpdj7sCZMT+zzZK2XLFaj7X10jYXHBHWTcf+8ccATli4VgRefjSM6l3Dc/WN1SxRVL2sscD/66Wi4HSm47EPX3WfITVCkmJi5thBSyVDLOUrHAObuZ+p+2fGeeotY1c5P6+LWl2ObN9GAiTNh8C/y5Qdl8+d/U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782885095; c=relaxed/simple; bh=eGjQpW20ZDis/hfCmp+TIg44Iy7vXmRa7MdWK0TFAjo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=nR8+RIiVsEnEux33aFlSdb+i78E/0o71z/H5JCZWL6EBU5iCWcgMH5j3/oP7qDmvrJ9qUT1q6L1OifsmNYmITrFJ3wpDxRcRNmW538hROSr4MDgeqjgRNpJdOl7bBNheGw6aZCEPFg7jfxMOugXVudZcEAyIHx143Ywnbt4Dmvo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=D9eddkM1; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="D9eddkM1" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 53F781F00A3A; Wed, 1 Jul 2026 05:51:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782885093; bh=HkzqvFMXi/PgU+6F3kPwXboJDV9YU/zrJk+hhy58TBA=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=D9eddkM1K/T7RTCiQTgtIU6lixFvLYa9EeEaz+wMOZQ+xlTWidBriJTTjKfVC/I5F DbEPOBhOq7rwUYznEf4REm9gXDeEp1M3sYIra0nuSE3fkyI6Su34Q67tLIRZacdrE8 EQ67aDfoPb3WmKbV8nNeJ4/20Zc1nX5lkSsP/2WmRmc1YI1xa0CTlyTefzlOAy/YGj Vd4sOpYAA/vjSVMCGCJNxPejK40j4RHBqNtyUxe8TUuSo7feSUehna+CJJvcFNrkLv kITtam5OAcs3m+jsILWL7XYWWvyqi0qndiFfiNXk+Mh6+l8mlKpTRdn0hEFQ8T4/ST /puqkd/i1b9OA== 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 10/22] dma-direct: use __DMA_ATTR_ALLOC_CC_SHARED in alloc/free paths Date: Wed, 1 Jul 2026 11:19:14 +0530 Message-ID: <20260701054926.825925-11-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> Precedence: bulk X-Mailing-List: linux-s390@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Propagate force_dma_unencrypted() into __DMA_ATTR_ALLOC_CC_SHARED in the dma-direct allocation path and use the attribute to drive the related decisions. This updates dma_direct_alloc(), dma_direct_free(), and dma_direct_alloc_pages() to fold the forced unencrypted case into attrs. Tested-by: Jiri Pirko Tested-by: Michael Kelley Tested-by: Mostafa Saleh Reviewed-by: Petr Tesarik Signed-off-by: Aneesh Kumar K.V (Arm) --- kernel/dma/direct.c | 42 +++++++++++++++++++++++++++++++++--------- kernel/dma/mapping.c | 9 +++++++++ 2 files changed, 42 insertions(+), 9 deletions(-) diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 0cbf2b0835c4..98e47e0b332d 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -192,16 +192,22 @@ void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs) { bool remap = false, set_uncached = false; - bool mark_mem_decrypt = true; + bool mark_mem_decrypt = false; struct page *page; void *ret; + if (force_dma_unencrypted(dev)) + attrs |= __DMA_ATTR_ALLOC_CC_SHARED; + + if (attrs & __DMA_ATTR_ALLOC_CC_SHARED) + mark_mem_decrypt = true; + size = PAGE_ALIGN(size); if (attrs & DMA_ATTR_NO_WARN) gfp |= __GFP_NOWARN; - if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) && - !force_dma_unencrypted(dev) && !is_swiotlb_for_alloc(dev)) + if (((attrs & (DMA_ATTR_NO_KERNEL_MAPPING | __DMA_ATTR_ALLOC_CC_SHARED)) == + DMA_ATTR_NO_KERNEL_MAPPING) && !is_swiotlb_for_alloc(dev)) return dma_direct_alloc_no_mapping(dev, size, dma_handle, gfp); if (!dev_is_dma_coherent(dev)) { @@ -235,7 +241,7 @@ void *dma_direct_alloc(struct device *dev, size_t size, * Remapping or decrypting memory may block, allocate the memory from * the atomic pools instead if we aren't allowed block. */ - if ((remap || force_dma_unencrypted(dev)) && + if ((remap || (attrs & __DMA_ATTR_ALLOC_CC_SHARED)) && dma_direct_use_pool(dev, gfp)) { page = dma_direct_alloc_from_pool(dev, size, dma_handle, &ret, gfp); @@ -314,12 +320,22 @@ void dma_direct_free(struct device *dev, size_t size, void *cpu_addr, dma_addr_t dma_addr, unsigned long attrs) { phys_addr_t phys; - bool mark_mem_encrypted = true; + bool mark_mem_encrypted = false; struct io_tlb_pool *swiotlb_pool; unsigned int page_order = get_order(size); - if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) && - !force_dma_unencrypted(dev) && !is_swiotlb_for_alloc(dev)) { + /* + * If the allocation used decrypted/shared backing pages, restore + * the encryption state on free. + */ + if (force_dma_unencrypted(dev)) + attrs |= __DMA_ATTR_ALLOC_CC_SHARED; + + if (attrs & __DMA_ATTR_ALLOC_CC_SHARED) + mark_mem_encrypted = true; + + if (((attrs & (DMA_ATTR_NO_KERNEL_MAPPING | __DMA_ATTR_ALLOC_CC_SHARED)) == + DMA_ATTR_NO_KERNEL_MAPPING) && !is_swiotlb_for_alloc(dev)) { /* cpu_addr is a struct page cookie, not a kernel address */ dma_free_contiguous(dev, cpu_addr, size); return; @@ -368,10 +384,14 @@ void dma_direct_free(struct device *dev, size_t size, struct page *dma_direct_alloc_pages(struct device *dev, size_t size, dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp) { + unsigned long attrs = 0; struct page *page; void *ret; - if (force_dma_unencrypted(dev) && dma_direct_use_pool(dev, gfp)) + if (force_dma_unencrypted(dev)) + attrs |= __DMA_ATTR_ALLOC_CC_SHARED; + + if ((attrs & __DMA_ATTR_ALLOC_CC_SHARED) && dma_direct_use_pool(dev, gfp)) return dma_direct_alloc_from_pool(dev, size, dma_handle, &ret, gfp); if (is_swiotlb_for_alloc(dev)) { @@ -405,7 +425,11 @@ void dma_direct_free_pages(struct device *dev, size_t size, phys_addr_t phys; void *vaddr = page_address(page); struct io_tlb_pool *swiotlb_pool; - bool mark_mem_encrypted = true; + /* + * if the device had requested for an unencrypted buffer, + * convert it to encrypted on free + */ + bool mark_mem_encrypted = force_dma_unencrypted(dev); /* If page is not from an atomic pool, dma_free_from_pool_page() fails */ if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) && diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index 4fe04669e5e6..d2f70b6ccd0f 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -638,6 +638,15 @@ void *dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle, if (WARN_ON_ONCE(flag & __GFP_COMP)) return NULL; + if (attrs & (DMA_ATTR_CC_SHARED | __DMA_ATTR_ALLOC_CC_SHARED)) { + trace_dma_alloc(dev, NULL, 0, size, DMA_BIDIRECTIONAL, flag, + attrs); + return NULL; + } + + if (force_dma_unencrypted(dev)) + attrs |= __DMA_ATTR_ALLOC_CC_SHARED; + if (dma_alloc_from_dev_coherent(dev, size, dma_handle, &cpu_addr)) { trace_dma_alloc(dev, cpu_addr, *dma_handle, size, DMA_BIDIRECTIONAL, flag, attrs); -- 2.43.0