From f29ab49b5388b2f829cf99859bc5f8ad8ec4d06a Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Fri, 16 Mar 2018 14:25:40 +0100 Subject: [PATCH] dma-mapping: Convert NO_DMA get_dma_ops() into a real dummy If NO_DMA=y, get_dma_ops() returns a reference to the non-existing symbol bad_dma_ops, thus causing a link failure if it is ever used. Make get_dma_ops() return NULL instead, to avoid the link failure. This allows to improve compile-testing, and limits the need to keep on sprinkling dependencies on HAS_DMA all over the place. Signed-off-by: Geert Uytterhoeven Reviewed-by: Mark Brown Acked-by: Robin Murphy Signed-off-by: Christoph Hellwig --- include/linux/dma-mapping.h | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index eb9eab4ecd6d..5ea7eec83c0f 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -212,14 +212,14 @@ static inline void set_dma_ops(struct device *dev, } #else /* - * Define the dma api to allow compilation but not linking of - * dma dependent code. Code that depends on the dma-mapping - * API needs to set 'depends on HAS_DMA' in its Kconfig + * Define the dma api to allow compilation of dma dependent code. + * Code that depends on the dma-mapping API needs to set 'depends on HAS_DMA' + * in its Kconfig, unless it already depends on || COMPILE_TEST, + * where guarantuees the availability of the dma-mapping API. */ -extern const struct dma_map_ops bad_dma_ops; static inline const struct dma_map_ops *get_dma_ops(struct device *dev) { - return &bad_dma_ops; + return NULL; } #endif -- 2.30.2