Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit b8664554 authored by Christoph Hellwig's avatar Christoph Hellwig
Browse files

dma-mapping: add a dma_addressing_limited helper 



This helper returns if the device has issues addressing all present
memory in the system.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
parent 9087c375

include/linux/dma-mapping.h

+14 −0
Original line number Diff line number Diff line
@@ -679,6 +679,20 @@ static inline int dma_coerce_mask_and_coherent(struct device *dev, u64 mask) 
	return dma_set_mask_and_coherent(dev, mask);

}



/**

 * dma_addressing_limited - return if the device is addressing limited

 * @dev:	device to check

 *

 * Return %true if the devices DMA mask is too small to address all memory in

 * the system, else %false.  Lack of addressing bits is the prime reason for

 * bounce buffering, but might not be the only one.

 */

static inline bool dma_addressing_limited(struct device *dev)

{

	return min_not_zero(*dev->dma_mask, dev->bus_dma_mask) <

		dma_get_required_mask(dev);

}



#ifdef CONFIG_ARCH_HAS_SETUP_DMA_OPS

void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,

		const struct iommu_ops *iommu, bool coherent);