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 B46823502AA; Fri, 17 Apr 2026 08:59:53 +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=1776416393; cv=none; b=CUcfWRsrmqa8TPJIsRFmACri6jzfOyKb0tQaNymd6elU47DD07/+Z1ngQ9tt4EbyppKFMiBZLbI/uzJhY/4GcGmPWT8oK6vM/mT9+daKeGX2OadN1Mhcf5SJtzRsN+EDDYRGkJDPARUQ7vC8HSWZfrtxR4g8cTy0BQqWnmDe+h8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776416393; c=relaxed/simple; bh=NPbjsIwD8g92JzX7wavhGqNdM/uKMVtRfW7D98XYiN8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ns3XYfRA3Kuo6A4x0hEwjKtMuz61dJG3ohaPDl7gLtL6nNWfTFdAePE3zLlhMnmh7KkW3N3GCquzl3rlrw4Q2X9jrGyn/50cfNVgC+8xDtEwe+puZJPj3ovIolNBKl8k79EYm3hTXIOvtCK0hGnxUPZD9x+qaa9rA7FWoMGtMlk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Epe/MGSF; 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="Epe/MGSF" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EA0B8C2BCB4; Fri, 17 Apr 2026 08:59:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1776416393; bh=NPbjsIwD8g92JzX7wavhGqNdM/uKMVtRfW7D98XYiN8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Epe/MGSFe4LhtiLh5F3B0DyNUxwgoFjUeHAdnR/a0AoFxWN+qUWy3/H6QmDht6TZP tszrpsItkyMs2DEF8uExjRyBo4rcFTWfYtNIJP9s6ZTgqw74cyMETg+jQhwa/5KaR+ iOQ7DQZCGZ8TrFc2T8JoISKW2SCfIuWkXHwDB+pyIy82Wa9SuS5viORnWFgfsb/VWr V//1WojvoQJX5VSxF2j3zCt/9b9KVC1EIy6Xnv3vdaIvGYZjqLFeWqTzsYPwODmzWu 57gHWWOAB0JQ8tGpW/nnAvrcyqWZBHrGVGsIJtmMTeJP+TOgCfzuj5nDWvCbRIfIzK 1f1+GYdUG3S2w== From: "Aneesh Kumar K.V (Arm)" To: iommu@lists.linux.dev, linux-kernel@vger.kernel.org Cc: robin.murphy@arm.com, m.szyprowski@samsung.com, will@kernel.org, maz@kernel.org, suzuki.poulose@arm.com, catalin.marinas@arm.com, jiri@resnulli.us, jgg@ziepe.ca, aneesh.kumar@kernel.org, Mostafa Saleh Subject: [RFC PATCH 2/7] dma-direct: use DMA_ATTR_CC_DECRYPTED in alloc/free paths Date: Fri, 17 Apr 2026 14:28:55 +0530 Message-ID: <20260417085900.3062416-3-aneesh.kumar@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260417085900.3062416-1-aneesh.kumar@kernel.org> References: <20260417085900.3062416-1-aneesh.kumar@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Propagate force_dma_unencrypted() into DMA_ATTR_CC_DECRYPTED 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. Signed-off-by: Aneesh Kumar K.V (Arm) --- kernel/dma/direct.c | 34 ++++++++++++++++++++++++++-------- 1 file changed, 26 insertions(+), 8 deletions(-) diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index c2a43e4ef902..3932033f4d8c 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -201,16 +201,21 @@ 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 = !!(attrs & DMA_ATTR_CC_DECRYPTED); struct page *page; void *ret; + if (force_dma_unencrypted(dev)) { + attrs |= DMA_ATTR_CC_DECRYPTED; + 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_CC_DECRYPTED)) == + 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)) { @@ -244,7 +249,7 @@ 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_CC_DECRYPTED)) && dma_direct_use_pool(dev, gfp)) return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp); @@ -318,11 +323,20 @@ void *dma_direct_alloc(struct device *dev, size_t size, void dma_direct_free(struct device *dev, size_t size, void *cpu_addr, dma_addr_t dma_addr, unsigned long attrs) { - bool mark_mem_encrypted = true; + bool mark_mem_encrypted = !!(attrs & DMA_ATTR_CC_DECRYPTED); 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 device had requested for an unencrypted buffer, + * convert it to encrypted on free + */ + if (force_dma_unencrypted(dev)) { + attrs |= DMA_ATTR_CC_DECRYPTED; + mark_mem_encrypted = true; + } + + if (((attrs & (DMA_ATTR_NO_KERNEL_MAPPING | DMA_ATTR_CC_DECRYPTED)) == + 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; @@ -365,10 +379,14 @@ 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_CC_DECRYPTED; + + if ((attrs & DMA_ATTR_CC_DECRYPTED) && dma_direct_use_pool(dev, gfp)) return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp); if (is_swiotlb_for_alloc(dev)) { -- 2.43.0