[PATCH 05/20] swiotlb: allow the architecture to provide a get_required_mask hook

[Christoph Hellwig]

For now this allows consolidating the powerpc code.  In the long run
we should grow a generic implementation of dma_get_required_mask that
returns the dma mask required to avoid bounce buffering.

Signed-off-by: Christoph Hellwig <hch at lst.de>
---
 kernel/dma/swiotlb.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 904541055792..1bb420244753 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -1084,5 +1084,9 @@ const struct dma_map_ops swiotlb_dma_ops = {
 	.map_page		= swiotlb_map_page,
 	.unmap_page		= swiotlb_unmap_page,
 	.dma_supported		= dma_direct_supported,
+#ifdef swiotlb_get_required_mask
+	.get_required_mask	= swiotlb_get_required_mask,
+#endif
+
 };
 EXPORT_SYMBOL(swiotlb_dma_ops);
-- 
2.18.0