s390/dma: provide dma_cache_sync() function

Provide empty dma_cache_sync() function.

Acked-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 5 insertions, 2 deletions

diff --git a/arch/s390/include/asm/dma-mapping.h b/arch/s390/include/asm/dma-mapping.h
index 8a32f7dfd3af..e74bc7ac72e0 100644
--- a/arch/s390/include/asm/dma-mapping.h
+++ b/arch/s390/include/asm/dma-mapping.h
@@ -20,8 +20,11 @@ static inline struct dma_map_ops *get_dma_ops(struct device *dev)
 
 extern int dma_set_mask(struct device *dev, u64 mask);
 extern int dma_is_consistent(struct device *dev, dma_addr_t dma_handle);
-extern void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
-                           enum dma_data_direction direction);
+
+static inline void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
+                                  enum dma_data_direction direction)
+{
+}
 
 #define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
 #define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)