[PATCH v3 2/8] dma: contiguous: Make dev_get_cma_area() a proper function

[Maxime Ripard <mripard@kernel.org>]

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 <mripard@kernel.org>
---
 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..6b8e6a2a08e2cb380de764bd6cacb2cb24c22871 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 */
 
 #ifdef CONFIG_DMA_CMA
 extern struct cma *dma_contiguous_default_area;
 
-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);
 
 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);
 
@@ -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 gfp);
 void dma_free_contiguous(struct device *dev, struct page *page, size_t size);
 
 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 long 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
 
 #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..9a9ed7248fb823105609c5db5a51113e54a40192 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 != -1;
 }
 
+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
 
 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];

-- 
2.53.0