[PATCH 1/2] dma-mapping: make dma_max_mapping_size() return 0 for no DMA capability

[John Garry <john.g.garry@oracle.com>]

For when a device is not DMA capable, the max mapping size would be 0, so
make dma_max_mapping_size() reflect that.

Signed-off-by: John Garry <john.g.garry@oracle.com>
---
 kernel/dma/mapping.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c
index 4fe04669e5e66..7e576e5c6b8be 100644
--- a/kernel/dma/mapping.c
+++ b/kernel/dma/mapping.c
@@ -979,6 +979,9 @@ size_t dma_max_mapping_size(struct device *dev)
 	const struct dma_map_ops *ops = get_dma_ops(dev);
 	size_t size = SIZE_MAX;
 
+	if (!dev->dma_mask)
+		return 0;
+
 	if (dma_map_direct(dev, ops))
 		size = dma_direct_max_mapping_size(dev);
 	else if (use_dma_iommu(dev))
-- 
2.43.7