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 AECB8C4451B for ; Fri, 17 Jul 2026 18:07:05 +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=vhd8ARWkryxrWwIm7KhnUETWTJknCTz38d8nlJNnprQ=; b=QEUb6MaQeGyuFezTUvmnAGCiqB BJrkNTxDMJu2YSH6sMER+IL3Wt1cErf5mO1KtqdRkX88YoDCDu0GMYzBMSR/HQ6Fm+7Pz0wTX0LIe 6YDzgTBiP0kG02+AqZgJ+2K3IBU2axKSQd3hYcA/ogGkTnoszgao7niCCDRjl/teRlZGZeJfOJSVp 7Bsab3qW8WAyYiKFzc5JX5zXxOEPD60KD6yXVl0i45/U9xCTvG9PLCddTJp6JRwxUN8NOJr//ApO3 M2l4UpLAHi0mdkkRxVGOJ73uug6nn2NRdyXQIW0/tBDonPHnnUFZH3c3RIP8ICnUYAvbBgXpDc3LX yx25v4JA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wkmxf-00000002xNZ-1Jst; Fri, 17 Jul 2026 18:06:59 +0000 Received: from tor.source.kernel.org ([172.105.4.254]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wkmxe-00000002xN9-0S1m for linux-arm-kernel@lists.infradead.org; Fri, 17 Jul 2026 18:06:58 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 887C1600DA; Fri, 17 Jul 2026 18:06:57 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 048FD1F00A3E; Fri, 17 Jul 2026 18:06:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784311617; bh=vhd8ARWkryxrWwIm7KhnUETWTJknCTz38d8nlJNnprQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Fi0KoA/ePSpIRE6p1P5b8WFj1HHt45EONpGIMYarmdrr1D5rMvl72euUoRDCMuAM5 zbeOwFDh1wXeyO8ALlxZFBuERXeseFibb2X7SfQmBMZZu0aN+qj3jemlAp3kGIiUKe mcLRmeyxuqKJYqs2KS0bLnr0BsTahuIrZZ6vcCiEzJaUeJ4buInrCfJUxPSBq5Bsgs Pi2IbRpiAZtnRvzumFiAOIBzWPl9t2T4Pxb3s+4HEiFSeWSZTMdAfR9k1jfLRXWiTx xC3pkQeeojY0PZQppL0wtTp5QF0B6dswPMnrADubzvnEBSGIECjumBnzUR10MFNUFS KJzLvycPv1HOA== 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, Jason Gunthorpe , Jiri Pirko , Michael Kelley Subject: [PATCH v8 10/23] dma-direct: use __DMA_ATTR_ALLOC_CC_SHARED in alloc/free paths Date: Fri, 17 Jul 2026 23:34:28 +0530 Message-ID: <20260717180442.110954-11-aneesh.kumar@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260717180442.110954-1-aneesh.kumar@kernel.org> References: <20260717180442.110954-1-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 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. Reviewed-by: Jason Gunthorpe 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 171c89fe99c9..1b49ba5e0a60 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