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 1370B36167B; Wed, 1 Jul 2026 05:53:02 +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=1782885184; cv=none; b=pjnAE8IwwchneAbKl1ZuOQxiwzcOl1+oloRyo23K5qcT+FUhnEtINQB2yqpi9S2Pyfj9GtTy5acquYwjd3kCRVdSdQYCj7/5Ucqzq7N2rdPIeXmWIylnaWiZJkJbU/xi7PcOs1SHzLKW27Sb0w7LypUigllPvnu+fBvoFxjB/MA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782885184; c=relaxed/simple; bh=cAxUL/obMKZBuxkQLs2iF/zP2cZJO6rSC2sK3tdvlrU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=IU1nYAsIPvjIakmp6ONs6itIk49buBSRTDuscKnlbXwOl1OfyT3RugQ7h+2MiR3HcnOnjaapsWbq2OdsAAglpE57R7yRIq1oz+RjRJ64lTu5aWs1B5xMSIo0vaGjZeUsQ3SEIgbd0vrqkyOM01no9SROSkLjQr+4tqrrfo4rZNI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=KYXAmDET; 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="KYXAmDET" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4CA131F000E9; Wed, 1 Jul 2026 05:52:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782885182; bh=xGRP07sIXhOW44W0Ke99D2HU+/3eVzVVhpBppwd6XuY=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=KYXAmDETQoVnPCedruRosGhHHuYgs8Ksa+15kuSAy9mlvG+SewOgGs8QqTR7oH9VE 8yfWyOl+XaW7dVBghqoeUWxGOM1LmS4I33tZM3LC9YoDRAYGuG7YmDQaAFXM8Mr7N3 d320gNJpf4Oxrsp4TCIZ7qZe6ptDHvB3Xvf/8uErjhj9No0KXlF9MOCS1xBLO22mWr f2Gmj4t+D3fmjYusGweBMYw2yUbn2NPud7Jhy1Ae6kGkshpn6ymFSXUk34Es4/aU4E g5YFwO+fPqmfhToeqJtsUtse4pzJt3tV2WGFtPjXimKWQFmDPCShZbfbFqSkVOWm19 aVkmW1/9K1Z3g== 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 18/22] dma-direct: select DMA address encoding from __DMA_ATTR_ALLOC_CC_SHARED Date: Wed, 1 Jul 2026 11:19:22 +0530 Message-ID: <20260701054926.825925-19-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 Make the dma-direct helpers derive the DMA address encoding from __DMA_ATTR_ALLOC_CC_SHARED instead of implicitly relying on force_dma_unencrypted() inside phys_to_dma_direct() Pass an explicit unencrypted/decrypted state into phys_to_dma_direct(), make the alloc paths return DMA addresses that match the requested buffer encryption state. Also only call dma_set_decrypted() when __DMA_ATTR_ALLOC_CC_SHARED is actually set. Tested-by: Jiri Pirko Tested-by: Michael Kelley Tested-by: Mostafa Saleh Signed-off-by: Aneesh Kumar K.V (Arm) --- kernel/dma/direct.c | 43 ++++++++++++++++++++++++++----------------- 1 file changed, 26 insertions(+), 17 deletions(-) diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 964e8b0d8709..23138519cf22 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -24,11 +24,11 @@ u64 zone_dma_limit __ro_after_init = DMA_BIT_MASK(24); static inline dma_addr_t phys_to_dma_direct(struct device *dev, - phys_addr_t phys) + phys_addr_t phys, bool unencrypted) { - if (force_dma_unencrypted(dev)) + if (unencrypted) return phys_to_dma_unencrypted(dev, phys); - return phys_to_dma(dev, phys); + return phys_to_dma_encrypted(dev, phys); } static inline struct page *dma_direct_to_page(struct device *dev, @@ -39,8 +39,9 @@ static inline struct page *dma_direct_to_page(struct device *dev, u64 dma_direct_get_required_mask(struct device *dev) { + bool require_decrypted = force_dma_unencrypted(dev); phys_addr_t phys = ((phys_addr_t)max_pfn << PAGE_SHIFT) - 1; - u64 max_dma = phys_to_dma_direct(dev, phys); + u64 max_dma = phys_to_dma_direct(dev, phys, require_decrypted); return (1ULL << (fls64(max_dma) - 1)) * 2 - 1; } @@ -69,7 +70,8 @@ static gfp_t dma_direct_optimal_gfp_mask(struct device *dev, u64 *phys_limit) bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size) { - dma_addr_t dma_addr = phys_to_dma_direct(dev, phys); + bool require_decrypted = force_dma_unencrypted(dev); + dma_addr_t dma_addr = phys_to_dma_direct(dev, phys, require_decrypted); if (dma_addr == DMA_MAPPING_ERROR) return false; @@ -79,17 +81,18 @@ bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size) static int dma_set_decrypted(struct device *dev, void *vaddr, size_t size) { - if (!force_dma_unencrypted(dev)) - return 0; - return set_memory_decrypted((unsigned long)vaddr, PFN_UP(size)); + int ret; + + ret = set_memory_decrypted((unsigned long)vaddr, PFN_UP(size)); + if (ret) + pr_warn_ratelimited("leaking DMA memory that can't be decrypted\n"); + return ret; } static int dma_set_encrypted(struct device *dev, void *vaddr, size_t size) { int ret; - if (!force_dma_unencrypted(dev)) - return 0; ret = set_memory_encrypted((unsigned long)vaddr, PFN_UP(size)); if (ret) pr_warn_ratelimited("leaking DMA memory that can't be re-encrypted\n"); @@ -169,7 +172,8 @@ static struct page *dma_direct_alloc_from_pool(struct device *dev, size_t size, dma_coherent_ok); if (!page) return NULL; - *dma_handle = phys_to_dma_direct(dev, page_to_phys(page)); + *dma_handle = phys_to_dma_direct(dev, page_to_phys(page), + !!(attrs & __DMA_ATTR_ALLOC_CC_SHARED)); return page; } @@ -185,9 +189,11 @@ static void *dma_direct_alloc_no_mapping(struct device *dev, size_t size, /* remove any dirty cache lines on the kernel alias */ if (!PageHighMem(page)) arch_dma_prep_coherent(page, size); - - /* return the page pointer as the opaque cookie */ - *dma_handle = phys_to_dma_direct(dev, page_to_phys(page)); + /* + * return the page pointer as the opaque cookie. + * Never used for unencrypted allocation + */ + *dma_handle = phys_to_dma_encrypted(dev, page_to_phys(page)); return page; } @@ -324,7 +330,8 @@ void *dma_direct_alloc(struct device *dev, size_t size, ret = uncached_cpu_addr; } - *dma_handle = phys_to_dma_direct(dev, page_to_phys(page)); + *dma_handle = phys_to_dma_direct(dev, page_to_phys(page), + !!(attrs & __DMA_ATTR_ALLOC_CC_SHARED)); return ret; @@ -445,11 +452,13 @@ struct page *dma_direct_alloc_pages(struct device *dev, size_t size, return NULL; ret = page_address(page); - if (dma_set_decrypted(dev, ret, size)) + if ((attrs & __DMA_ATTR_ALLOC_CC_SHARED) && + dma_set_decrypted(dev, ret, size)) goto out_leak_pages; setup_page: memset(ret, 0, size); - *dma_handle = phys_to_dma_direct(dev, page_to_phys(page)); + *dma_handle = phys_to_dma_direct(dev, page_to_phys(page), + !!(attrs & __DMA_ATTR_ALLOC_CC_SHARED)); return page; out_leak_pages: return NULL; -- 2.43.0