Commit 8ae0e970 authored by Jia He's avatar Jia He Committed by Christoph Hellwig
Browse files

dma-mapping: move dma_addressing_limited() out of line 



This patch moves dma_addressing_limited() out of line, serving as a
preliminary step to prevent the introduction of a new publicly accessible
low-level helper when validating whether all system RAM is mapped within
the DMA mapping range.

Suggested-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarJia He <justin.he@arm.com>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
parent a5e3b127

include/linux/dma-mapping.h

+5 −14
Original line number Diff line number Diff line
@@ -144,6 +144,7 @@ bool dma_pci_p2pdma_supported(struct device *dev); 
int dma_set_mask(struct device *dev, u64 mask);

int dma_set_coherent_mask(struct device *dev, u64 mask);

u64 dma_get_required_mask(struct device *dev);

bool dma_addressing_limited(struct device *dev);

size_t dma_max_mapping_size(struct device *dev);

size_t dma_opt_mapping_size(struct device *dev);

bool dma_need_sync(struct device *dev, dma_addr_t dma_addr);
@@ -264,6 +265,10 @@ static inline u64 dma_get_required_mask(struct device *dev) 
{

	return 0;

}

static inline bool dma_addressing_limited(struct device *dev)

{

	return false;

}

static inline size_t dma_max_mapping_size(struct device *dev)

{

	return 0;
@@ -465,20 +470,6 @@ 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(dma_get_mask(dev), dev->bus_dma_limit) <

			    dma_get_required_mask(dev);

}



static inline unsigned int dma_get_max_seg_size(struct device *dev)

{

	if (dev->dma_parms && dev->dma_parms->max_segment_size)

kernel/dma/mapping.c

+15 −0
Original line number Diff line number Diff line
@@ -793,6 +793,21 @@ int dma_set_coherent_mask(struct device *dev, u64 mask) 
}

EXPORT_SYMBOL(dma_set_coherent_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.

 */

bool dma_addressing_limited(struct device *dev)

{

	return min_not_zero(dma_get_mask(dev), dev->bus_dma_limit) <

			    dma_get_required_mask(dev);

}

EXPORT_SYMBOL_GPL(dma_addressing_limited);



size_t dma_max_mapping_size(struct device *dev)

{

	const struct dma_map_ops *ops = get_dma_ops(dev);