Commit f45cfab2 authored by Leon Romanovsky's avatar Leon Romanovsky Committed by Christoph Hellwig
Browse files

dma-mapping: reliably inform about DMA support for IOMMU 

If the DMA IOMMU path is going to be used, the appropriate check should
return that DMA is supported.

Fixes: b5c58b2f ("dma-mapping: direct calls for dma-iommu")
Closes: https://lore.kernel.org/all/181e06ff-35a3-434f-b505-672f430bd1cb@notapiano


Reported-by: Nícolas F. R. A. Prado <nfraprado@collabora.com> #KernelCI
Signed-off-by: default avatarLeon Romanovsky <leonro@nvidia.com>
Reviewed-by: default avatarRobin Murphy <robin.murphy@arm.com>
Tested-by: default avatarNícolas F. R. A. Prado <nfraprado@collabora.com>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
parent 038eb433

kernel/dma/mapping.c

+3 −0
Original line number Diff line number Diff line
@@ -843,6 +843,9 @@ static int dma_supported(struct device *dev, u64 mask) 


	if (WARN_ON(ops && use_dma_iommu(dev)))

		return false;



	if (use_dma_iommu(dev))

		return true;

	/*

	 * ->dma_supported sets the bypass flag, so we must always call

	 * into the method here unless the device is truly direct mapped.