From nobody Thu Apr 16 02:01:07 2026 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 E60313822A3; Tue, 3 Mar 2026 10:13:19 +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=1772532800; cv=none; b=IniJvKhPSoSFfsCStHauMRIuywBOl7ZMMC/6w3D9sNpHciBlRp5ddLSY4GYI/hoeJc5OGteaCV/IoPDp8hqmlRUAPDOjQLawQmTLPZeMkBkO0lCVOg965kz8HFrwxtTUDXCpHl6spLEk55uvIoAe8dRnB7lUEt9bHO9kcAcuO4I= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772532800; c=relaxed/simple; bh=9Km9m0AXCUr/a6vgKJn4EecEuoKphraVZQe3lTzETlY=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=QzejMNktP6gbi6Gq7o9agla8uFywM57PLUflQqwSGEwcSkmB8wV9cwFL9DB31O0hPkQz6jzSUL/68C3EUblP3JcDcTqNk+q170yqDTTRlYFq9kOS1itPiKRo/A4uRK0ouVgbw70tp9epETqMDhoNacKTkkUmKGLjoyppIKzlX9M= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=D2d7GSce; 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="D2d7GSce" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 71B84C2BC87; Tue, 3 Mar 2026 10:13:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772532799; bh=9Km9m0AXCUr/a6vgKJn4EecEuoKphraVZQe3lTzETlY=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=D2d7GSceo2GvP+dNzIPEP4ShcHqDj1mZkp1iu8UOhrVMZYMWVxIbp/uP0T8ZscKi3 lngmQRRXkWN8GJJy1USDTQDtf4yW1r8QgxmoRtmMSaYOPXIKSFgss9LpbTJ5Yg0rTD pNTx7dsao1Ox1bbzxWwaJFwXR2f3AKEmTvFHdc9JfPH9cX9guJskLgK3FnAMbA7p9C EA+gvFd7dwRHQPOsaXjGXpS9PunNElnwDCZOjYjLtxqiFDzE9tvzEs8KsmR2jjLyQK tksUQmnOgbG8ky7g+hY6Zy0WOGt9+MUFsBzRcYsYcsHPadDecoBXGFN1M7kuPi5ISq H3NYMxITNv3dw== From: Maxime Ripard Date: Tue, 03 Mar 2026 11:13:04 +0100 Subject: [PATCH v3 1/8] dma: contiguous: Turn heap registration logic around Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260303-dma-buf-heaps-as-modules-v3-1-24344812c707@kernel.org> References: <20260303-dma-buf-heaps-as-modules-v3-0-24344812c707@kernel.org> In-Reply-To: <20260303-dma-buf-heaps-as-modules-v3-0-24344812c707@kernel.org> To: Sumit Semwal , Benjamin Gaignard , Brian Starkey , John Stultz , "T.J. Mercier" , =?utf-8?q?Christian_K=C3=B6nig?= , Marek Szyprowski , Robin Murphy , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko Cc: Albert Esteve , linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-kernel@vger.kernel.org, iommu@lists.linux.dev, linux-mm@kvack.org, Maxime Ripard X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=5204; i=mripard@kernel.org; h=from:subject:message-id; bh=9Km9m0AXCUr/a6vgKJn4EecEuoKphraVZQe3lTzETlY=; b=owGbwMvMwCmsHn9OcpHtvjLG02pJDJnLtphcSmn/y3jh6D3phd9vaE3RX6ltOKNy1+XtUx2OB Tzt5GRt7JjKwiDMySArpsjyRCbs9PL2xVUO9it/wMxhZQIZwsDFKQATYVFnbGj5sJbFUM67h2PH hA7JXQ4z0h+aWR8X9knqjfgoICOf3Rd59O4CUxXT8//n/nUI+bH5HGOdAscG6Q8rXDcVixxdFl+ rmbC/wcZwQ/9q8xWqW1wND084VFlcvqCpM9r12sRjkvc+M2sBAA== X-Developer-Key: i=mripard@kernel.org; a=openpgp; fpr=BE5675C37E818C8B5764241C254BCFC56BF6CE8D The CMA heap instantiation was initially developed by having the contiguous DMA code call into the CMA heap to create a new instance every time a reserved memory area is probed. Turning the CMA heap into a module would create a dependency of the kernel on a module, which doesn't work. Let's turn the logic around and do the opposite: store all the reserved memory CMA regions into the contiguous DMA code, and provide an iterator for the heap to use when it probes. Reviewed-by: T.J. Mercier Reviewed-by: Albert Esteve Signed-off-by: Maxime Ripard --- drivers/dma-buf/heaps/cma_heap.c | 18 ++---------------- include/linux/dma-map-ops.h | 5 +++++ kernel/dma/contiguous.c | 26 ++++++++++++++++++++++++-- 3 files changed, 31 insertions(+), 18 deletions(-) diff --git a/drivers/dma-buf/heaps/cma_heap.c b/drivers/dma-buf/heaps/cma_h= eap.c index bd3370b9a3f6d4e18885a1d0e8ba3f659b85ef47..f8a3d87f3ccee9630383ba28502= eb40b10671cc2 100644 --- a/drivers/dma-buf/heaps/cma_heap.c +++ b/drivers/dma-buf/heaps/cma_heap.c @@ -28,23 +28,10 @@ #include #include =20 #define DEFAULT_CMA_NAME "default_cma_region" =20 -static struct cma *dma_areas[MAX_CMA_AREAS] __initdata; -static unsigned int dma_areas_num __initdata; - -int __init dma_heap_cma_register_heap(struct cma *cma) -{ - if (dma_areas_num >=3D ARRAY_SIZE(dma_areas)) - return -EINVAL; - - dma_areas[dma_areas_num++] =3D cma; - - return 0; -} - struct cma_heap { struct dma_heap *heap; struct cma *cma; }; =20 @@ -412,22 +399,21 @@ static int __init __add_cma_heap(struct cma *cma, con= st char *name) } =20 static int __init add_cma_heaps(void) { struct cma *default_cma =3D dev_get_cma_area(NULL); + struct cma *cma; unsigned int i; int ret; =20 if (default_cma) { ret =3D __add_cma_heap(default_cma, DEFAULT_CMA_NAME); if (ret) return ret; } =20 - for (i =3D 0; i < dma_areas_num; i++) { - struct cma *cma =3D dma_areas[i]; - + for (i =3D 0; (cma =3D dma_contiguous_get_reserved_region(i)) !=3D NULL; = i++) { ret =3D __add_cma_heap(cma, cma_get_name(cma)); if (ret) { pr_warn("Failed to add CMA heap %s", cma_get_name(cma)); continue; } diff --git a/include/linux/dma-map-ops.h b/include/linux/dma-map-ops.h index 60b63756df821d839436618f1fca2bfa3eabe075..3007c68a8ec5b85990d1938d04a= 2f05c1a71acdb 100644 --- a/include/linux/dma-map-ops.h +++ b/include/linux/dma-map-ops.h @@ -110,10 +110,11 @@ bool dma_release_from_contiguous(struct device *dev, = struct page *pages, int count); struct page *dma_alloc_contiguous(struct device *dev, size_t size, gfp_t g= fp); void dma_free_contiguous(struct device *dev, struct page *page, size_t siz= e); =20 void dma_contiguous_early_fixup(phys_addr_t base, unsigned long size); +struct cma *dma_contiguous_get_reserved_region(unsigned int idx); #else /* CONFIG_DMA_CMA */ static inline struct cma *dev_get_cma_area(struct device *dev) { return NULL; } @@ -148,10 +149,14 @@ static inline void dma_free_contiguous(struct device = *dev, struct page *page, __free_pages(page, get_order(size)); } static inline void dma_contiguous_early_fixup(phys_addr_t base, unsigned l= ong size) { } +static inline struct cma *dma_contiguous_get_reserved_region(unsigned int = idx) +{ + return NULL; +} #endif /* CONFIG_DMA_CMA*/ =20 #ifdef CONFIG_DMA_DECLARE_COHERENT int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr, dma_addr_t device_addr, size_t size); diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c index c56004d314dc2e436cddf3b20a4ee6ce8178bee4..14bd54fb758537f01a6fe27318e= 7b683964e20b1 100644 --- a/kernel/dma/contiguous.c +++ b/kernel/dma/contiguous.c @@ -456,10 +456,32 @@ void dma_free_contiguous(struct device *dev, struct p= age *page, size_t size) #include =20 #undef pr_fmt #define pr_fmt(fmt) fmt =20 +static struct cma *rmem_cma_areas[MAX_CMA_AREAS]; +static unsigned int rmem_cma_areas_num; + +static int rmem_cma_insert_area(struct cma *cma) +{ + if (rmem_cma_areas_num >=3D ARRAY_SIZE(rmem_cma_areas)) + return -EINVAL; + + rmem_cma_areas[rmem_cma_areas_num++] =3D cma; + + return 0; +} + +struct cma *dma_contiguous_get_reserved_region(unsigned int idx) +{ + if (idx >=3D rmem_cma_areas_num) + return NULL; + + return rmem_cma_areas[idx]; +} +EXPORT_SYMBOL_GPL(dma_contiguous_get_reserved_region); + static int rmem_cma_device_init(struct reserved_mem *rmem, struct device *= dev) { dev->cma_area =3D rmem->priv; return 0; } @@ -504,13 +526,13 @@ static int __init rmem_cma_setup(struct reserved_mem = *rmem) rmem->priv =3D cma; =20 pr_info("Reserved memory: created CMA memory pool at %pa, size %ld MiB\n", &rmem->base, (unsigned long)rmem->size / SZ_1M); =20 - err =3D dma_heap_cma_register_heap(cma); + err =3D rmem_cma_insert_area(cma); if (err) - pr_warn("Couldn't register CMA heap."); + pr_warn("Couldn't store CMA reserved area."); =20 return 0; } RESERVEDMEM_OF_DECLARE(cma, "shared-dma-pool", rmem_cma_setup); #endif --=20 2.53.0 From nobody Thu Apr 16 02:01:07 2026 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 C13A439A040; Tue, 3 Mar 2026 10:13:22 +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=1772532802; cv=none; b=lkjfkpzguo8YvSCcZUXHlA6gfd8dQhlMQg3yOB3IFrpRW6XOaqQiTliE/j8lNGMBgCneStZdfGXPsiK5TOp44a/sPSoUVS4DG60oHPG5FllFod0Dh+/sb2kA/jr1c5LT8qql4YK/wxWqi1V+kWrM+5JwZlPqApA/UdEzUV1XOUE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772532802; c=relaxed/simple; bh=OLrC2gz6cLkaWEzaVtzoFaeIC7TEtGhHt07Be27ESoM=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; 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charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260303-dma-buf-heaps-as-modules-v3-2-24344812c707@kernel.org> References: <20260303-dma-buf-heaps-as-modules-v3-0-24344812c707@kernel.org> In-Reply-To: <20260303-dma-buf-heaps-as-modules-v3-0-24344812c707@kernel.org> To: Sumit Semwal , Benjamin Gaignard , Brian Starkey , John Stultz , "T.J. Mercier" , =?utf-8?q?Christian_K=C3=B6nig?= , Marek Szyprowski , Robin Murphy , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko Cc: Albert Esteve , linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-kernel@vger.kernel.org, iommu@lists.linux.dev, linux-mm@kvack.org, Maxime Ripard X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=3660; i=mripard@kernel.org; h=from:subject:message-id; bh=OLrC2gz6cLkaWEzaVtzoFaeIC7TEtGhHt07Be27ESoM=; b=owGbwMvMwCmsHn9OcpHtvjLG02pJDJnLtpiclLx3kGf/5vRYa76ZT/++XXtwl4ClullX0jTzC zl9jnE8HVNZGIQ5GWTFFFmeyISdXt6+uMrBfuUPmDmsTCBDGLg4BWAiZ6czNhzRX7oyU8B/peFN C5E76zj7fy11eThPiytk/8yn0ytlZF1V8865P/tgt/GgyAXtcIGrkxnrtDkPTDmzIy5g+b3PnTw 5Tbutf/FGFWYbXrMrkJ1y+fakExrzq0TethjsTOKQnNxgI7YNAA== X-Developer-Key: i=mripard@kernel.org; a=openpgp; fpr=BE5675C37E818C8B5764241C254BCFC56BF6CE8D As we try to enable dma-buf heaps, and the CMA one in particular, to compile as modules, we need to export dev_get_cma_area(). It's currently implemented as an inline function that returns either the content of device->cma_area or dma_contiguous_default_area. Thus, it means we need to export dma_contiguous_default_area, which isn't really something we want any module to have access to. Instead, let's make dev_get_cma_area() a proper function we will be able to export so we can avoid exporting dma_contiguous_default_area. Signed-off-by: Maxime Ripard --- include/linux/dma-map-ops.h | 15 +++++++-------- kernel/dma/contiguous.c | 8 ++++++++ 2 files changed, 15 insertions(+), 8 deletions(-) diff --git a/include/linux/dma-map-ops.h b/include/linux/dma-map-ops.h index 3007c68a8ec5b85990d1938d04a2f05c1a71acdb..6b8e6a2a08e2cb380de764bd6ca= cb2cb24c22871 100644 --- a/include/linux/dma-map-ops.h +++ b/include/linux/dma-map-ops.h @@ -91,16 +91,11 @@ static inline void set_dma_ops(struct device *dev, #endif /* CONFIG_ARCH_HAS_DMA_OPS */ =20 #ifdef CONFIG_DMA_CMA extern struct cma *dma_contiguous_default_area; =20 -static inline struct cma *dev_get_cma_area(struct device *dev) -{ - if (dev && dev->cma_area) - return dev->cma_area; - return dma_contiguous_default_area; -} +struct cma *dev_get_cma_area(struct device *dev); =20 void dma_contiguous_reserve(phys_addr_t addr_limit); int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base, phys_addr_t limit, struct cma **res_cma, bool fixed); =20 @@ -110,11 +105,10 @@ bool dma_release_from_contiguous(struct device *dev, = struct page *pages, int count); struct page *dma_alloc_contiguous(struct device *dev, size_t size, gfp_t g= fp); void dma_free_contiguous(struct device *dev, struct page *page, size_t siz= e); =20 void dma_contiguous_early_fixup(phys_addr_t base, unsigned long size); -struct cma *dma_contiguous_get_reserved_region(unsigned int idx); #else /* CONFIG_DMA_CMA */ static inline struct cma *dev_get_cma_area(struct device *dev) { return NULL; } @@ -149,15 +143,20 @@ static inline void dma_free_contiguous(struct device = *dev, struct page *page, __free_pages(page, get_order(size)); } static inline void dma_contiguous_early_fixup(phys_addr_t base, unsigned l= ong size) { } +#endif /* CONFIG_DMA_CMA*/ + +#if defined(CONFIG_DMA_CMA) && defined(CONFIG_OF_RESERVED_MEM) +struct cma *dma_contiguous_get_reserved_region(unsigned int idx); +#else static inline struct cma *dma_contiguous_get_reserved_region(unsigned int = idx) { return NULL; } -#endif /* CONFIG_DMA_CMA*/ +#endif =20 #ifdef CONFIG_DMA_DECLARE_COHERENT int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr, dma_addr_t device_addr, size_t size); void dma_release_coherent_memory(struct device *dev); diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c index 14bd54fb758537f01a6fe27318e7b683964e20b1..9a9ed7248fb823105609c5db5a5= 1113e54a40192 100644 --- a/kernel/dma/contiguous.c +++ b/kernel/dma/contiguous.c @@ -99,10 +99,18 @@ early_param("cma", early_cma); bool __init cma_skip_dt_default_reserved_mem(void) { return size_cmdline !=3D -1; } =20 +struct cma *dev_get_cma_area(struct device *dev) +{ + if (dev && dev->cma_area) + return dev->cma_area; + + return dma_contiguous_default_area; +} + #ifdef CONFIG_DMA_NUMA_CMA =20 static struct cma *dma_contiguous_numa_area[MAX_NUMNODES]; static phys_addr_t numa_cma_size[MAX_NUMNODES] __initdata; static struct cma *dma_contiguous_pernuma_area[MAX_NUMNODES]; --=20 2.53.0 From nobody Thu Apr 16 02:01:07 2026 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 C59743988FF; 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dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="CYrAVUhL" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 10289C2BC87; Tue, 3 Mar 2026 10:13:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772532805; bh=/kD6F1ZhpnmLA/clOq4s+dTJhu8QKey3+LKztnUIF5o=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=CYrAVUhLcajw0Hs2gmC7vITgu9E3uQi3s+JDHWTE6IMBijS9oIioAh8MReB57fC+W VBChglhx2cEWfjmxfPe2urdQuwHQugtQBgVSXl9cM4LdoUzSuQA4ChjI//qRcD/PsX V+jZC4Dnz3MDiWQoEBHOVX+Bp/UEkLDaun9hnvQGs02U5arp2Q7TJS6eLMBi3T+vDa OJmT5m9BSWcj/GsWoTf4hjEEmJv4beLLwIqspBL1rM4HIkTxa6s/VR4P1wgB8psaZI apERoK/GEY0CTLHnMFT6kxxP3t3P7GGKapmnVrC/5uxyo9ZihIQC1hN0ShuAeGScLH fhl/wWxSiFjlw== From: Maxime Ripard Date: Tue, 03 Mar 2026 11:13:06 +0100 Subject: [PATCH v3 3/8] dma: contiguous: Make dma_contiguous_default_area static Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260303-dma-buf-heaps-as-modules-v3-3-24344812c707@kernel.org> References: <20260303-dma-buf-heaps-as-modules-v3-0-24344812c707@kernel.org> In-Reply-To: <20260303-dma-buf-heaps-as-modules-v3-0-24344812c707@kernel.org> To: Sumit Semwal , Benjamin Gaignard , Brian Starkey , John Stultz , "T.J. Mercier" , =?utf-8?q?Christian_K=C3=B6nig?= , Marek Szyprowski , Robin Murphy , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko Cc: Albert Esteve , linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-kernel@vger.kernel.org, iommu@lists.linux.dev, linux-mm@kvack.org, Maxime Ripard X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=1675; i=mripard@kernel.org; h=from:subject:message-id; bh=/kD6F1ZhpnmLA/clOq4s+dTJhu8QKey3+LKztnUIF5o=; b=owGbwMvMwCmsHn9OcpHtvjLG02pJDJnLtpg++eZieDDufVSmyImd5x7eO7LSXnZ2kGrvloxHM 7ou7txV2jGVhUGYk0FWTJHliUzY6eXti6sc7Ff+gJnDygQyhIGLUwAm4hzNWB/txW9UyDu53uyb 8NtD5exPzyyeJvI323Hl6r/5Z7PtXq1IDovoS8yS+fow87/PHIZ9hxkb7sp+WsI9Ked2lzTPDrH PlWdO3I3//IerfdJsgyt/VofN3JTl/Osgc/58+ZMub3YovPj8DAA= X-Developer-Key: i=mripard@kernel.org; a=openpgp; fpr=BE5675C37E818C8B5764241C254BCFC56BF6CE8D Now that dev_get_cma_area() is no longer inline, we don't have any user of dma_contiguous_default_area() outside of contiguous.c so we can make it static. Signed-off-by: Maxime Ripard --- include/linux/dma-map-ops.h | 2 -- kernel/dma/contiguous.c | 2 +- 2 files changed, 1 insertion(+), 3 deletions(-) diff --git a/include/linux/dma-map-ops.h b/include/linux/dma-map-ops.h index 6b8e6a2a08e2cb380de764bd6cacb2cb24c22871..94fbf16646c105fa2e1d34d407a= 830bf989d4fc8 100644 --- a/include/linux/dma-map-ops.h +++ b/include/linux/dma-map-ops.h @@ -89,12 +89,10 @@ static inline void set_dma_ops(struct device *dev, { } #endif /* CONFIG_ARCH_HAS_DMA_OPS */ =20 #ifdef CONFIG_DMA_CMA -extern struct cma *dma_contiguous_default_area; - struct cma *dev_get_cma_area(struct device *dev); =20 void dma_contiguous_reserve(phys_addr_t addr_limit); int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base, phys_addr_t limit, struct cma **res_cma, bool fixed); diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c index 9a9ed7248fb823105609c5db5a51113e54a40192..a4279d800d4658bf1c33b9b1da1= 00eee1367d42f 100644 --- a/kernel/dma/contiguous.c +++ b/kernel/dma/contiguous.c @@ -51,11 +51,11 @@ #define CMA_SIZE_MBYTES CONFIG_CMA_SIZE_MBYTES #else #define CMA_SIZE_MBYTES 0 #endif =20 -struct cma *dma_contiguous_default_area; +static struct cma *dma_contiguous_default_area; =20 /* * Default global CMA area size can be defined in kernel's .config. * This is useful mainly for distro maintainers to create a kernel * that works correctly for most supported systems. --=20 2.53.0 From nobody Thu Apr 16 02:01:07 2026 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 9FF383112AD; Tue, 3 Mar 2026 10:13:29 +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=1772532809; cv=none; b=Ux+WbMtdIA4bwYYNlpbYSGk2lxIy7LDYjMthM8oeOGPnb2XuKDAF4CvHl8bUhC6Z8j+nbfVVi1OjY07aTGXCa4XVrM6w597870rh4EKa3hJKaG+1Qrm1aqL3eb4aUJalIADVcAFN6SJ86/T2J9G6gppM9gqn9MxZ764scFu92MY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772532809; c=relaxed/simple; bh=0cHZ5LTDrjAloaUBF1Lu8YxebKzlQ2YWzvzsPNmbff4=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=BphOSzHB6iIVIGGAG3ZNfM1YBN2ZvEgzO3a9Gfd/w8yWBWh+/N+SUeesX+FKOQca0hSiQMQ9N6Ksl+Cc5I7XqQRObUVahi9sQ6e1OMWBliLlgshOhcBPaX9Gv4IVyVvsVnCP+pwe8zB/A1yTZOKlalN6ORrc0HmOqeKo2gLkFFQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=GhiXIqIF; 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="GhiXIqIF" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E906FC116C6; Tue, 3 Mar 2026 10:13:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772532809; bh=0cHZ5LTDrjAloaUBF1Lu8YxebKzlQ2YWzvzsPNmbff4=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=GhiXIqIFH0pFdYOVF4v4vn3elAc684typ5RQw/1l4WLHgkKnANNAhTHgTa3ZCshI3 IrWaY8DZnVM0Oimi0CVwPTFymDhv2Yy4FSm4OiqnjTt6tanBc4J/pHsTGVGjtlhPkj gnM2J+eS8+Ekvz4itIaa27OozlW4J+QHuGWCq1oRv+S/c1vI/k3uMlyGh6CSQLFtNI LfHn5u2j7yXmci2q+10ex5iIsC4GlWch4cZ9SL/aK0jiLFQEv2ODRZgl/BP8XCsR8q Oo7ncNQwHpA2Yqi0w5i2xVC8aU/v0Z7+pp2C25p48QE1sOZsJyhEn8FGVBD+4J8jw0 QAY9Syplot4RQ== From: Maxime Ripard Date: Tue, 03 Mar 2026 11:13:07 +0100 Subject: [PATCH v3 4/8] dma: contiguous: Export dev_get_cma_area() Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260303-dma-buf-heaps-as-modules-v3-4-24344812c707@kernel.org> References: <20260303-dma-buf-heaps-as-modules-v3-0-24344812c707@kernel.org> In-Reply-To: <20260303-dma-buf-heaps-as-modules-v3-0-24344812c707@kernel.org> To: Sumit Semwal , Benjamin Gaignard , Brian Starkey , John Stultz , "T.J. Mercier" , =?utf-8?q?Christian_K=C3=B6nig?= , Marek Szyprowski , Robin Murphy , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko Cc: Albert Esteve , linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-kernel@vger.kernel.org, iommu@lists.linux.dev, linux-mm@kvack.org, Maxime Ripard X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=953; i=mripard@kernel.org; h=from:subject:message-id; bh=0cHZ5LTDrjAloaUBF1Lu8YxebKzlQ2YWzvzsPNmbff4=; b=owGbwMvMwCmsHn9OcpHtvjLG02pJDJnLtpj+rwkN3X/RpsuSU2dZw8NGZodEu44ndV5bp/3o/ 35Koc+hYyoLgzAng6yYIssTmbDTy9sXVznYr/wBM4eVCWQIAxenAEzkpDxjw9e/Pz8anKhvkrF8 sNnTxsdyWoBDzfXAqfzWaRYfNtt5fPuXZFtreMhjzyq+ULZqxaZ7jA0TT9p3q2TbaX26JehvL3n nmvPl+QkR19KKX7fc8uiSFT6342m2tU9zoP2FdxcjxXo3SAEA X-Developer-Key: i=mripard@kernel.org; a=openpgp; fpr=BE5675C37E818C8B5764241C254BCFC56BF6CE8D The CMA dma-buf heap uses the dev_get_cma_area() function to retrieve the default contiguous area. Now that this function is no longer inlined, and since we want to turn the CMA heap into a module, let's export it. Signed-off-by: Maxime Ripard --- kernel/dma/contiguous.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c index a4279d800d4658bf1c33b9b1da100eee1367d42f..ad50512d71d3088a73e4b1ac02d= 6e6122374888e 100644 --- a/kernel/dma/contiguous.c +++ b/kernel/dma/contiguous.c @@ -106,10 +106,11 @@ struct cma *dev_get_cma_area(struct device *dev) if (dev && dev->cma_area) return dev->cma_area; =20 return dma_contiguous_default_area; } +EXPORT_SYMBOL_GPL(dev_get_cma_area); =20 #ifdef CONFIG_DMA_NUMA_CMA =20 static struct cma *dma_contiguous_numa_area[MAX_NUMNODES]; static phys_addr_t numa_cma_size[MAX_NUMNODES] __initdata; --=20 2.53.0 From nobody Thu Apr 16 02:01:07 2026 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 C12B43988EA; Tue, 3 Mar 2026 10:13:32 +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=1772532812; cv=none; b=oHrSluOLc7P1B3TujrxWiv3F9pIXu5756Ipko6Uq9fZ1MXh5Kk1YRgdfKe9tarlYZEzZ0Y3AUNAbL3upXxolHTpxXE3TzBlNowNqYHgN3ZfxGq7fAs5UYEuf1omMlq+QfMNv0KIu+XYkWAIZKzlDrPhkHkUMhTzxxHgy3J3yaVE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772532812; c=relaxed/simple; bh=xA8iRNbldwAg/IWB0t2FyV0TtMeqN3qjpeDuNnBZW50=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=HXUC20D3V3pwRwcbjbaCX0otb7o2s5DAe4SRMpcOBd3PRotaJ5MlEkw4taDmnhL2FGObrkwsfTfK92XqX+Etskax0QW+jwxYEFNbz/Wq/p/nMnrZe5I0mwO622ki6h5q2quXoI8D5rdPCKApI+P/CjqxEgjYdO0kCxw6BEPbbSc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=pPgkx2p7; 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="pPgkx2p7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 04EA2C2BC87; Tue, 3 Mar 2026 10:13:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772532812; bh=xA8iRNbldwAg/IWB0t2FyV0TtMeqN3qjpeDuNnBZW50=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=pPgkx2p7bpzUvd/y0QKqig3ahxphe4kIYCiDTUiIFaRnCdB//a24tY206c+r7nONd KNDWko0Wd/xQ2j8wBPpXsNNFf8VRbFKtp94fJDjouvNCWMQUKouXiJBtSzzkwCQb3M psJ4gGxLizIqeU5/kUS5bma/Cr8MOoIfYs8i6g2T/WJx6plTyDTTUX0dZn8U7WBBVp Gay4CxCD5wDgoChSafPUeZemEbEFRUS0nHGfskZ+7eriqjCXulHApxPzgUNCFG+MaO 7wrSTQEm+aAF0//lcx3KJz18HrLaCMy5e08kFc04VKFjchH+k7kYj3f1tj+WgJGEVX UNA2SlT10vImQ== From: Maxime Ripard Date: Tue, 03 Mar 2026 11:13:08 +0100 Subject: [PATCH v3 5/8] mm: cma: Export cma_alloc(), cma_release() and cma_get_name() Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260303-dma-buf-heaps-as-modules-v3-5-24344812c707@kernel.org> References: <20260303-dma-buf-heaps-as-modules-v3-0-24344812c707@kernel.org> In-Reply-To: <20260303-dma-buf-heaps-as-modules-v3-0-24344812c707@kernel.org> To: Sumit Semwal , Benjamin Gaignard , Brian Starkey , John Stultz , "T.J. Mercier" , =?utf-8?q?Christian_K=C3=B6nig?= , Marek Szyprowski , Robin Murphy , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko Cc: Albert Esteve , linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-kernel@vger.kernel.org, iommu@lists.linux.dev, linux-mm@kvack.org, Maxime Ripard X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=1725; i=mripard@kernel.org; h=from:subject:message-id; bh=xA8iRNbldwAg/IWB0t2FyV0TtMeqN3qjpeDuNnBZW50=; b=owGbwMvMwCmsHn9OcpHtvjLG02pJDJnLtphd3Lnadr6or7GS8X2FF0azNTvqpdYKHQia9sNbn 1359PLyjqksDMKcDLJiiixPZMJOL29fXOVgv/IHzBxWJpAhDFycAjCRM4GM9SGui34Wvzd8vOvY 1bhMG4Y1lTqzb63qZ5eM/ZS3MmtbhNhrK69pM+T4JoXGMamGN7w5y1inYxh0fM3PnfsrF8r+j1u 35B8Pi2sER1j147/7uzMV3/oU/lNY429dFsQf6FJZ337b6yAA X-Developer-Key: i=mripard@kernel.org; a=openpgp; fpr=BE5675C37E818C8B5764241C254BCFC56BF6CE8D The CMA dma-buf heap uses cma_alloc() and cma_release() to allocate and free, respectively, its CMA buffers, and cma_get_name() to get the name of the heap instance it's going to create. However, these functions are not exported. Since we want to turn the CMA heap into a module, let's export them both. Reviewed-by: T.J. Mercier Acked-by: David Hildenbrand (Arm) Signed-off-by: Maxime Ripard --- mm/cma.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/cma.c b/mm/cma.c index 94b5da468a7d719e5144d33b06bcc7619c0fbcc9..550effb9c4e01cc488b5744fe61= d55a5b70a6d6c 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -50,10 +50,11 @@ unsigned long cma_get_size(const struct cma *cma) =20 const char *cma_get_name(const struct cma *cma) { return cma->name; } +EXPORT_SYMBOL_GPL(cma_get_name); =20 static unsigned long cma_bitmap_aligned_mask(const struct cma *cma, unsigned int align_order) { if (align_order <=3D cma->order_per_bit) @@ -949,10 +950,11 @@ struct page *cma_alloc(struct cma *cma, unsigned long= count, if (page) set_pages_refcounted(page, count); =20 return page; } +EXPORT_SYMBOL_GPL(cma_alloc); =20 static struct cma_memrange *find_cma_memrange(struct cma *cma, const struct page *pages, unsigned long count) { struct cma_memrange *cmr =3D NULL; @@ -1025,10 +1027,11 @@ bool cma_release(struct cma *cma, const struct page= *pages, =20 __cma_release_frozen(cma, cmr, pages, count); =20 return true; } +EXPORT_SYMBOL_GPL(cma_release); =20 bool cma_release_frozen(struct cma *cma, const struct page *pages, unsigned long count) { struct cma_memrange *cmr; --=20 2.53.0 From nobody Thu Apr 16 02:01:07 2026 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 8E0533988EA; Tue, 3 Mar 2026 10:13:35 +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=1772532815; cv=none; b=oANv3KtvlBEOfDweq7ddcg13CBTlTTLgDZGt//CoCnxBLJN9c0Kqq2nNylgopadFIgHrDv75ClE5S6Sn9goygX7MjY7AnN6dB05UEMf8kJn0yRvdSVMRASCYdzlCOvPMdBsKWeAq4G8Nkz+rWzQSuY2v4J6QA2fWqwnyo5MOu4Q= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772532815; c=relaxed/simple; bh=uocFqI6buKhD72I9T9guormXJl46wyFDpX9g7jostug=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=HEb0YrB8Lr0ytc0CXtozN5nUyx8lDF0U+c3KgLeb6tk6Ut2JdHR4l2R+Gf6VFeWs4UXi+bPomkO7B0YBJRtnYIXwbCLBJEZmCnr09YBIWHZaAjWDKP0xVWrKv8Buisi5Vu3SxLqUItdFKzNenq22C+2EoyhLgenbaG0PMkXvC9E= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=hNLBgPiY; 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="hNLBgPiY" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C8734C2BCB4; Tue, 3 Mar 2026 10:13:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772532815; bh=uocFqI6buKhD72I9T9guormXJl46wyFDpX9g7jostug=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=hNLBgPiYlGA3ROspXiwDWvGd7UDC3eLt9KG+LRpD2ykmSpbvDT4i2lecDwEEQ4jRi BSriPRPByLDuUP07IrVg5AWs0lHcb/j5vNyXlRdfXxPb9Gmh21vG71c0O4goDaA8DR viJH+W2PiOP/skvF0y52/p3n1Sl8m2jC7WrjZr0ZyA4FFArGVbBpfR0/p7mifhP9zc vuxDO4mW0g4VCQk13LnYA04RoubMyd71KF6RRslLiRJyJYV8teAEPkxI4Uiht714lw Su6WskTLu+cqYWbaT0LYNfkORzEllBz+OkTHo9zVAvRkED584wGHpfE//bQQ6aVFHI qI0XQT+J6gALQ== From: Maxime Ripard Date: Tue, 03 Mar 2026 11:13:09 +0100 Subject: [PATCH v3 6/8] dma-buf: heaps: Export mem_accounting parameter Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260303-dma-buf-heaps-as-modules-v3-6-24344812c707@kernel.org> References: <20260303-dma-buf-heaps-as-modules-v3-0-24344812c707@kernel.org> In-Reply-To: <20260303-dma-buf-heaps-as-modules-v3-0-24344812c707@kernel.org> To: Sumit Semwal , Benjamin Gaignard , Brian Starkey , John Stultz , "T.J. Mercier" , =?utf-8?q?Christian_K=C3=B6nig?= , Marek Szyprowski , Robin Murphy , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko Cc: Albert Esteve , linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-kernel@vger.kernel.org, iommu@lists.linux.dev, linux-mm@kvack.org, Maxime Ripard X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=1114; i=mripard@kernel.org; h=from:subject:message-id; bh=uocFqI6buKhD72I9T9guormXJl46wyFDpX9g7jostug=; b=owGbwMvMwCmsHn9OcpHtvjLG02pJDJnLtpg51J64F2S+Qnv20d4+vXl7NF2OTUzZEbiAw+DT1 DTF2JqujqksDMKcDLJiiixPZMJOL29fXOVgv/IHzBxWJpAhDFycAjCRpGmM9W4hG/rbaxtq+/t+ TFZ9WZrIxbMl1Z5rxh2PTpe4RweTlh6aWsVRvk2v0+9XgXIBZ/ljxobDb3+d2ZoTr5IvGT05qeb NJsfWxCKRfpEylf23TWZPncb3e4tml+rbq5MZild+d9gZ/h0A X-Developer-Key: i=mripard@kernel.org; a=openpgp; fpr=BE5675C37E818C8B5764241C254BCFC56BF6CE8D The mem_accounting kernel parameter is used by heaps to know if they should account allocations in their respective cgroup controllers. Since we're going to allow heaps to compile as modules, we need to export that variable. Reviewed-by: T.J. Mercier Signed-off-by: Maxime Ripard --- drivers/dma-buf/dma-heap.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/dma-buf/dma-heap.c b/drivers/dma-buf/dma-heap.c index ac5f8685a649496c0e1c6decbf263b63fa472d04..a76bf3f8b071a3d5bf39a8513f3= 1e9e8aa16e02f 100644 --- a/drivers/dma-buf/dma-heap.c +++ b/drivers/dma-buf/dma-heap.c @@ -51,10 +51,11 @@ static DEFINE_XARRAY_ALLOC(dma_heap_minors); =20 bool __read_mostly mem_accounting; module_param(mem_accounting, bool, 0444); MODULE_PARM_DESC(mem_accounting, "Enable cgroup-based memory accounting for dma-buf heap allocations (de= fault=3Dfalse)."); +EXPORT_SYMBOL_NS_GPL(mem_accounting, "DMA_BUF_HEAP"); =20 static int dma_heap_buffer_alloc(struct dma_heap *heap, size_t len, u32 fd_flags, u64 heap_flags) { --=20 2.53.0 From nobody Thu Apr 16 02:01:07 2026 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 40A3F39B96A; Tue, 3 Mar 2026 10:13:38 +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=1772532818; cv=none; b=C6wqgIESBlmTGHGOBTH3h/ynL/5fC7naWWDp00nbgs4pV3m0hU3yz/+vwMn837K1iFwoPcIs960UJSAYzHysUpg8FPa8ucTrv1q8kwxV0OLn166CAJvjzc6G1Rj5AXBIMXXGuQvAIto14FfJ40u23kZLcnBFf1gnay9mZn3/heE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772532818; c=relaxed/simple; bh=lO+1PMKRSkJNghp2Ly48vsH4KqRxHWKQohidvl/pe2Y=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=JQj1IPuOW/+7LAsIzey20GQXKhdg5rrQR6gpQumiBk2eTJ/8LAVsgnyYXVg3eDqItwR8BgNTah4fLLVcYgH9btwpc5/DnC6MnE9zpWogOktBbY1iCrGiC5kuJF0fhrz3wQuXfVa1M3lDxJjxMk3LtHBXaMZwm3ayzte+i6rc82w= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ig/bQomu; 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="ig/bQomu" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C0FCFC2BC87; Tue, 3 Mar 2026 10:13:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772532818; bh=lO+1PMKRSkJNghp2Ly48vsH4KqRxHWKQohidvl/pe2Y=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=ig/bQomueXUc216uzemyo2U7Bbfzhcnc5nCEskK/mHG1BNSkp3GNVKQcUoQF5QbIs 3Ql14c7EzyAwIOLpNgE4RVLoyqF/JkOXcKr/QFwizysU/w7EMn4z9bPzaPwAzstxwA qMrhWoIKGCrBkZJD+FuOR1K3Y02+jGyn13qfMo5Xb2VgJnvXinZWmgj4b++CO37Pgh yo548YffVMv7oJbhtPYd/f+5y5R8sQgYxKJtoIuANg+MX9pwblSdpNvzWQ3qUhezm3 9yu90bIGAySB/Mh5tSVxPLc+Lt5oM+5mpj/Opk08gXnc1NdLEqAbSjMbSCRoX8FJ1R TwqT6cZiYZ5oA== From: Maxime Ripard Date: Tue, 03 Mar 2026 11:13:10 +0100 Subject: [PATCH v3 7/8] dma-buf: heaps: cma: Turn the heap into a module Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260303-dma-buf-heaps-as-modules-v3-7-24344812c707@kernel.org> References: <20260303-dma-buf-heaps-as-modules-v3-0-24344812c707@kernel.org> In-Reply-To: <20260303-dma-buf-heaps-as-modules-v3-0-24344812c707@kernel.org> To: Sumit Semwal , Benjamin Gaignard , Brian Starkey , John Stultz , "T.J. Mercier" , =?utf-8?q?Christian_K=C3=B6nig?= , Marek Szyprowski , Robin Murphy , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko Cc: Albert Esteve , linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-kernel@vger.kernel.org, iommu@lists.linux.dev, linux-mm@kvack.org, Maxime Ripard X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=1869; i=mripard@kernel.org; h=from:subject:message-id; bh=lO+1PMKRSkJNghp2Ly48vsH4KqRxHWKQohidvl/pe2Y=; b=owGbwMvMwCmsHn9OcpHtvjLG02pJDJnLtphp/tk9K/m380aGhrutlZoh089yhxn5CWXlbGD3E ntoFVfbMZWFQZiTQVZMkeWJTNjp5e2LqxzsV/6AmcPKBDKEgYtTACZyYCpjw96X696qrNmY0KzK lFh940Fc/q33m61bV6u/3VdYf+pliXaje4peib7Al+5/W58s2c2VyVhn8nfape47nK3J9Qv+sqe qN1urnd+w8b5he5eljsLOoJMfZbUsXh+WY/u3tvRlQu/97fsB X-Developer-Key: i=mripard@kernel.org; a=openpgp; fpr=BE5675C37E818C8B5764241C254BCFC56BF6CE8D Now that all the symbols used by the CMA heap are exported, turning the CMA heap into a module becomes pretty easy: we just need to add the usual MODULE_* macros, import the proper namespaces and change the Kconfig symbol to a tristate. This heap won't be able to unload though, since we're missing a lot of infrastructure to make it safe. Reviewed-by: T.J. Mercier Signed-off-by: Maxime Ripard --- drivers/dma-buf/heaps/Kconfig | 2 +- drivers/dma-buf/heaps/cma_heap.c | 3 +++ 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/dma-buf/heaps/Kconfig b/drivers/dma-buf/heaps/Kconfig index a5eef06c422644e8aadaf5aff2bd9a33c49c1ba3..aed0b9b4febf388376cfc41be98= 43980d010c4e8 100644 --- a/drivers/dma-buf/heaps/Kconfig +++ b/drivers/dma-buf/heaps/Kconfig @@ -4,11 +4,11 @@ config DMABUF_HEAPS_SYSTEM help Choose this option to enable the system dmabuf heap. The system heap is backed by pages from the buddy allocator. If in doubt, say Y. =20 config DMABUF_HEAPS_CMA - bool "DMA-BUF CMA Heap" + tristate "DMA-BUF CMA Heap" depends on DMABUF_HEAPS && DMA_CMA help Choose this option to enable dma-buf CMA heap. This heap is backed by the Contiguous Memory Allocator (CMA). If your system has these regions, you should say Y here. diff --git a/drivers/dma-buf/heaps/cma_heap.c b/drivers/dma-buf/heaps/cma_h= eap.c index f8a3d87f3ccee9630383ba28502eb40b10671cc2..7216a14262b04bb6130ddf26b7d= 009f7d15b03fd 100644 --- a/drivers/dma-buf/heaps/cma_heap.c +++ b/drivers/dma-buf/heaps/cma_heap.c @@ -422,5 +422,8 @@ static int __init add_cma_heaps(void) =20 return 0; } module_init(add_cma_heaps); MODULE_DESCRIPTION("DMA-BUF CMA Heap"); +MODULE_LICENSE("GPL"); +MODULE_IMPORT_NS("DMA_BUF"); +MODULE_IMPORT_NS("DMA_BUF_HEAP"); --=20 2.53.0 From nobody Thu Apr 16 02:01:07 2026 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 48355398906; Tue, 3 Mar 2026 10:13:41 +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=1772532821; cv=none; b=RdCiADiwyzLPY4uUD/Tv/pLEjwGVKuiaH0DINUJaU2xIwectUo40Gd37fiChISqGGa3sdwLSq5yc6Pp4t1Hw5Ip0GF6jywWneximj1DId/OSdZJBLTNQGfGCDGA4NbQxyyd3/TVOygWoQx6N08kVMskMugJdilC5e+NDl+27Afs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772532821; c=relaxed/simple; bh=oNUPt44D7xewgXiELSrkzONvN2UIFpJB+B1908QRT5k=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=MvqaXD+HxAUJnr7CFshKydfUh/6ZSlBrtrCYax4LB2B/rRTT68+iCc9tpwxWnSusLqqsLic1H65i/QlqF2DDAXYUVMwnvcQXORENpkB68vyUQUa+sLX+lNEmJtktlugBkOvbSHbqMkZ6Owpa+t96xS9UD5kkAVhWwyz22V4Ckoo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ADpL3jIO; 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="ADpL3jIO" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 86090C116C6; Tue, 3 Mar 2026 10:13:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772532820; bh=oNUPt44D7xewgXiELSrkzONvN2UIFpJB+B1908QRT5k=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=ADpL3jIOp1uDm7HSfLQGSaxxoDKfYlUUC08JfjkT40HIv1kDS6uscZlg/RFCc2D3i vyua0nD6EbOGZLWlIbC3nGpLFAAD9kZSZODn1YsjjXKvYLt1HSQZiK3J2GmjdZ/VJt u0AUVs22fHYQBvmXX+UTxO1B15J4umInL4/FFUCoWOXTCOZsN8Lh6llVp84TelzZa8 ZafeIsMhpE3tmLoC9PQPOY/NBEWCdu8a7lxDxfu/YO+KPLWrhd9hB/6z7/P7hrm9LT vvcJBOJ1Nfq+VVBen0KRd+bRSAAlmFLTA8hkquNtNt1lMRPCipCoubmNKTWqTf2wZR LO7hJLS1IUF0Q== From: Maxime Ripard Date: Tue, 03 Mar 2026 11:13:11 +0100 Subject: [PATCH v3 8/8] dma-buf: heaps: system: Turn the heap into a module Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260303-dma-buf-heaps-as-modules-v3-8-24344812c707@kernel.org> References: <20260303-dma-buf-heaps-as-modules-v3-0-24344812c707@kernel.org> In-Reply-To: <20260303-dma-buf-heaps-as-modules-v3-0-24344812c707@kernel.org> To: Sumit Semwal , Benjamin Gaignard , Brian Starkey , John Stultz , "T.J. Mercier" , =?utf-8?q?Christian_K=C3=B6nig?= , Marek Szyprowski , Robin Murphy , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko Cc: Albert Esteve , linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-kernel@vger.kernel.org, iommu@lists.linux.dev, linux-mm@kvack.org, Maxime Ripard X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=1645; i=mripard@kernel.org; h=from:subject:message-id; bh=oNUPt44D7xewgXiELSrkzONvN2UIFpJB+B1908QRT5k=; b=owGbwMvMwCmsHn9OcpHtvjLG02pJDJnLtpjLhZrIvOCLmau/886knTHtqxv8n09Nyyx+oDj3r ut8JWuVjqksDMKcDLJiiixPZMJOL29fXOVgv/IHzBxWJpAhDFycAjCR9M+MDZfKNSakNHG2Pu2p 1td90Ci2e9fvDWuKXH86fq/Yk+12TfOj9j8bR+VVB078FfeZUh1bwdjQcu2u7Sxvppnmbie/7F0 uZi/gaby1/Lhe87FY2drnoSW6kjGxWf3566oM18xsCS2xLwEA X-Developer-Key: i=mripard@kernel.org; a=openpgp; fpr=BE5675C37E818C8B5764241C254BCFC56BF6CE8D The system heap can be easily turned into a module by adding the usual MODULE_* macros, importing the proper namespaces and changing the Kconfig symbol to a tristate. This heap won't be able to unload though, since we're missing a lot of infrastructure to make it safe. Reviewed-by: T.J. Mercier Signed-off-by: Maxime Ripard --- drivers/dma-buf/heaps/Kconfig | 2 +- drivers/dma-buf/heaps/system_heap.c | 5 +++++ 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/dma-buf/heaps/Kconfig b/drivers/dma-buf/heaps/Kconfig index aed0b9b4febf388376cfc41be9843980d010c4e8..e273fb18feca091ccd9b406e68f= 86c12efb339e9 100644 --- a/drivers/dma-buf/heaps/Kconfig +++ b/drivers/dma-buf/heaps/Kconfig @@ -1,7 +1,7 @@ config DMABUF_HEAPS_SYSTEM - bool "DMA-BUF System Heap" + tristate "DMA-BUF System Heap" depends on DMABUF_HEAPS help Choose this option to enable the system dmabuf heap. The system heap is backed by pages from the buddy allocator. If in doubt, say Y. =20 diff --git a/drivers/dma-buf/heaps/system_heap.c b/drivers/dma-buf/heaps/sy= stem_heap.c index b3650d8fd6511a4a755612cfe3a9d9fee796f80e..1957403b0f2ae5e82ab39f5945d= fe82808e93964 100644 --- a/drivers/dma-buf/heaps/system_heap.c +++ b/drivers/dma-buf/heaps/system_heap.c @@ -442,5 +442,10 @@ static int __init system_heap_create(void) return PTR_ERR(sys_heap); =20 return 0; } module_init(system_heap_create); + +MODULE_DESCRIPTION("DMA-BUF System Heap"); +MODULE_LICENSE("GPL"); +MODULE_IMPORT_NS("DMA_BUF"); +MODULE_IMPORT_NS("DMA_BUF_HEAP"); --=20 2.53.0