dma-contiguous: remove dma_contiguous_set_default

dma_contiguous_set_default contains a trivial assignment, and has a
single caller that is compiled if CONFIG_CMA_DMA is enabled.
Signed-off-by: NChristoph Hellwig <hch@lst.de>

include/linux/dma-contiguous.h

@@ -66,11 +66,6 @@ static inline struct cma *dev_get_cma_area(struct device *dev)
 	return dma_contiguous_default_area;
 }
 
-static inline void dma_contiguous_set_default(struct cma *cma)
-{
-	dma_contiguous_default_area = cma;
-}
-
 void dma_contiguous_reserve(phys_addr_t addr_limit);
 
 int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base,
@@ -91,8 +86,6 @@ static inline struct cma *dev_get_cma_area(struct device *dev)
 	return NULL;
 }
 
-static inline void dma_contiguous_set_default(struct cma *cma) { }
-
 static inline void dma_contiguous_reserve(phys_addr_t limit) { }
 
 static inline int dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base,

kernel/dma/contiguous.c

@@ -407,7 +407,7 @@ static int __init rmem_cma_setup(struct reserved_mem *rmem)
 	dma_contiguous_early_fixup(rmem->base, rmem->size);
 
 	if (default_cma)
-		dma_contiguous_set_default(cma);
+		dma_contiguous_default_area = cma;
 
 	rmem->ops = &rmem_cma_ops;
 	rmem->priv = cma;