From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793810930; b=0xtAJI2mIt9Rq7wcz//0Fug/tjZSxAm1SdaaqueDuJD6EkNTpw912I/7cytbADyt4bGw agu+6w/hqnzsGhN2Uz/BI+Qxqc8J85zrBaajoXF7HBB4aQj8k7XKJuHEIbDY+D3FsZ5d3 pxcOnP+C8HZIHLb5S3tvnlAlEl+I276B5IBoLFoLl5LgqNqqhdv79YgGP8h+dIwBWMw0f 7SNZ+mlQgpoWV7B0gnXDHF3Oct7BWveZqFDi1o4CLJT8n4UAMH/7DPXfSbwNnaKkx0wRu X1MtwzDcHHi+HpQQqUYf+8SgxRJ75NEJuH14qCNlw3k94vWnJT01JUCuO2V3sE+UdgQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793810930; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=IUSaeFo1mvVEk8no6IM15BHOisJ9Uj3pDx22Qt7gIqY=; b=F5TgBxNrOnM3x3wNKkERbSci+nmWKCCqfTFT9hAd9jgJAJxwYNYAo/T0x1MtDfCcDNAY 0ZtlVofWEPA3Er+RJ8SDhlnpolE1PuHvD6rThJpbj+lS2tF37gN7o2qCga3D5oNOdF3wP Ca7uaL2wctSL5AjOiOKLl82wwCu4+pWV9kXi9JIItnQiRZESspYAEA1a2JH2DL+oZd63a TFH1OU0A6N3/C9m0cnCB1B8cFi2CtTPI3Funw7ei/yWQSDXgIMsI6Cgj3wFc62g+3amkG Y/Iziw5HGKlNvHOH8fkVHmf0TR6KC8YENS/UvbA+7FM/qJV4tWFqp3AIQKH0wBeZN5w== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b="b/tfrxuQ"; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3376A606A32C; Wed, 4 Nov 2026 16:48:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=b/tfrxuQ Received: by smtp.kernel.org (Postfix) with ESMTPSA id 097861F000C1; Wed, 4 Nov 2026 16:48:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793810929; bh=IUSaeFo1mvVEk8no6IM15BHOisJ9Uj3pDx22Qt7gIqY=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=b/tfrxuQIUxCoioD2PwWww9Ln+574VOwed455Mv9HrfrGanJlx1Y6TvHWjvbOKWnV jvT7d4rTNPrjkJuvDQLyFj5/jSP/HOZoHzaeyJrKbHvzNu4L55Nsu6kfOxe/wQS5xE ClcQv6WNLXUucKAO36vkeHc+NkA3ytQtfmCJyFV1OnZRPyxi5Qh4Y4OiZt83rlCZaG 2Kv5nyYhBXjKPYWTj+J4FFgq3A5stC6UrkXpWw/rXxzFn3hwpKiEA1plDXUvx/fO8X +mOIudidEOaWxfRgoCyOmmREgHYbSQQtcJbnncOn3fPtjYm9dPl+c06oqAL9s0ClsO uPAGXnsM7VctA== From: "Aneesh Kumar K.V (Arm)" To: linux-coco@lists.linux.dev Cc: "Aneesh Kumar K.V (Arm)" , Andrew Morton , Baoquan He , Mike Rapoport , Pasha Tatashin , Pratyush Yadav , Catalin Marinas , =?UTF-8?q?Christian=20K=C3=B6nig?= , Jason Gunthorpe , Joerg Roedel , Marc Zyngier , Marek Szyprowski , Robin Murphy , Steven Price , Sumit Semwal , Suzuki K Poulose , Thomas Gleixner , Will Deacon , Russell King , Benjamin Gaignard , Brian Starkey , John Stultz , Mark Rutland , Radu Rendec , "T.J. Mercier" , Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , Christophe Leroy , Ritesh Harjani , Shrikanth Hegde , Alexander Gordeev , Gerald Schaefer , Heiko Carstens , Vasily Gorbik , Christian Borntraeger , Sven Schnelle , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H . Peter Anvin" , Kiryl Shutsemau , Rick Edgecombe , "K . Y . Srinivasan" , Haiyang Zhang , Wei Liu , Dexuan Cui , Long Li , Paolo Bonzini , Vitaly Kuznetsov , Andy Lutomirski , Peter Zijlstra , dri-devel@lists.freedesktop.org, iommu@lists.linux.dev, linaro-mm-sig@lists.linaro.org, linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org, linux-mm@kvack.org, kvmarm@lists.linux.dev, patches@lists.linux.dev Subject: [PATCH v9 07/14] dma-direct: Align CoCo shared DMA allocations to the shared granule size Date: Wed, 4 Nov 2026 22:15:48 +0530 Message-ID: <20261104164555.3555725-8-aneesh.kumar@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20261104164555.3555725-1-aneesh.kumar@kernel.org> References: <20261104164555.3555725-1-aneesh.kumar@kernel.org> X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Use the common CoCo shared-memory geometry helpers for allocations backed directly by CMA or the page allocator. Round the backing allocation to a whole shared granule and pass the resolved shared-allocation attribute through the DMA contiguous allocator so it can enforce the mandatory alignment. Transition the complete range through the common shared/private helpers. Recompute the layout before freeing ordinary direct allocations so the transition back to private memory and dma_free_contiguous() cover exactly the range acquired by the allocation path. If restoring private state fails, retain the existing fail-safe behavior and leak the pages rather than returning potentially shared memory to the allocator. This also applies the same rules to dma_direct_alloc_pages(), covering callers which require a struct page result rather than a CPU virtual address. Cc: Marek Szyprowski Cc: Robin Murphy Signed-off-by: Aneesh Kumar K.V (Arm) --- kernel/dma/direct.c | 51 ++++++++++++++++++++++++++++++++++----------- 1 file changed, 39 insertions(+), 12 deletions(-) diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 7e71f96b6ffd..675ed698a3ad 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -11,10 +11,10 @@ #include #include #include -#include #include #include #include +#include #include "direct.h" @@ -85,7 +85,7 @@ static int dma_set_decrypted(struct device *dev, void *vaddr, size_t size) { int ret; - ret = set_memory_decrypted((unsigned long)vaddr, PFN_UP(size)); + ret = cc_make_shared(vaddr, size); if (ret) pr_warn_ratelimited("leaking DMA memory that can't be decrypted\n"); return ret; @@ -95,7 +95,7 @@ static int dma_set_encrypted(struct device *dev, void *vaddr, size_t size) { int ret; - ret = set_memory_encrypted((unsigned long)vaddr, PFN_UP(size)); + ret = cc_make_private(vaddr, size); if (ret) pr_warn_ratelimited("leaking DMA memory that can't be re-encrypted\n"); return ret; @@ -115,7 +115,7 @@ static struct page *dma_direct_alloc_swiotlb(struct device *dev, size_t size, } static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size, - gfp_t gfp, bool allow_highmem) + gfp_t gfp, bool allow_highmem, unsigned long attrs) { int node = dev_to_node(dev); struct page *page; @@ -125,7 +125,7 @@ static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size, WARN_ON_ONCE(!PAGE_ALIGNED(size)); gfp |= dma_direct_optimal_gfp_mask(dev, &phys_limit); - page = dma_alloc_contiguous(dev, size, gfp, 0); + page = dma_alloc_contiguous(dev, size, gfp, attrs); if (page) { if (dma_coherent_ok(dev, page_to_phys(page), size) && (allow_highmem || !PageHighMem(page))) @@ -202,7 +202,7 @@ static void *dma_direct_alloc_no_mapping(struct device *dev, size_t size, { struct page *page; - page = __dma_direct_alloc_pages(dev, size, gfp & ~__GFP_ZERO, true); + page = __dma_direct_alloc_pages(dev, size, gfp & ~__GFP_ZERO, true, 0); if (!page) return NULL; @@ -223,6 +223,7 @@ void *dma_direct_alloc(struct device *dev, size_t size, bool remap = false, set_uncached = false; bool mark_mem_decrypt = false; bool allow_highmem = true; + struct cc_shared_layout layout; struct page *page; void *cpu_addr; @@ -302,8 +303,15 @@ void *dma_direct_alloc(struct device *dev, size_t size, return NULL; } + if (mark_mem_decrypt) { + if (cc_shared_calc_layout(size, &layout)) + return NULL; + size = layout.shared_size; + } + /* we always manually zero the memory once we are done */ - page = __dma_direct_alloc_pages(dev, size, gfp & ~__GFP_ZERO, allow_highmem); + page = __dma_direct_alloc_pages(dev, size, gfp & ~__GFP_ZERO, + allow_highmem, attrs); if (!page) return NULL; @@ -322,7 +330,7 @@ void *dma_direct_alloc(struct device *dev, size_t size, void *lm_addr; lm_addr = page_address(page); - if (set_memory_decrypted((unsigned long)lm_addr, PFN_UP(size))) + if (dma_set_decrypted(dev, lm_addr, size)) goto out_leak_pages; } @@ -381,6 +389,7 @@ void dma_direct_free(struct device *dev, size_t size, phys_addr_t phys; bool mark_mem_encrypted = false; struct io_tlb_pool *swiotlb_pool; + struct cc_shared_layout layout; unsigned int page_order = get_order(size); /* @@ -424,6 +433,12 @@ void dma_direct_free(struct device *dev, size_t size, /* Swiotlb doesn't need a page attribute update on free */ mark_mem_encrypted = false; + if (mark_mem_encrypted) { + if (WARN_ON_ONCE(cc_shared_calc_layout(size, &layout))) + return; + size = layout.shared_size; + } + if (is_vmalloc_addr(cpu_addr)) { vunmap(cpu_addr); } else { @@ -435,10 +450,8 @@ void dma_direct_free(struct device *dev, size_t size, void *lm_addr; lm_addr = phys_to_virt(phys); - if (set_memory_encrypted((unsigned long)lm_addr, PFN_UP(size))) { - pr_warn_ratelimited("leaking DMA memory that can't be re-encrypted\n"); + if (dma_set_encrypted(dev, lm_addr, size)) return; - } } if (swiotlb_pool) @@ -451,6 +464,7 @@ 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 cc_shared_layout layout; struct page *page; void *cpu_addr; bool mark_mem_decrypt; @@ -474,7 +488,13 @@ struct page *dma_direct_alloc_pages(struct device *dev, size_t size, goto setup_page; } - page = __dma_direct_alloc_pages(dev, size, gfp, false); + if (mark_mem_decrypt) { + if (cc_shared_calc_layout(size, &layout)) + return NULL; + size = layout.shared_size; + } + + page = __dma_direct_alloc_pages(dev, size, gfp, false, attrs); if (!page) return NULL; @@ -500,6 +520,7 @@ 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; + struct cc_shared_layout layout; /* * if the device had requested for an unencrypted buffer, * convert it to encrypted on free @@ -516,6 +537,12 @@ void dma_direct_free_pages(struct device *dev, size_t size, if (swiotlb_pool) mark_mem_encrypted = false; + if (mark_mem_encrypted) { + if (WARN_ON_ONCE(cc_shared_calc_layout(size, &layout))) + return; + size = layout.shared_size; + } + if (mark_mem_encrypted && dma_set_encrypted(dev, vaddr, size)) return; -- 2.43.0