Commit f7326196 authored by Leon Romanovsky's avatar Leon Romanovsky Committed by Marek Szyprowski
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dma-mapping: export new dma_*map_phys() interface 



Introduce new DMA mapping functions dma_map_phys() and dma_unmap_phys()
that operate directly on physical addresses instead of page+offset
parameters. This provides a more efficient interface for drivers that
already have physical addresses available.

The new functions are implemented as the primary mapping layer, with
the existing dma_map_page_attrs()/dma_map_resource() and
dma_unmap_page_attrs()/dma_unmap_resource() functions converted to simple
wrappers around the phys-based implementations.

In case dma_map_page_attrs(), the struct page is converted to physical
address with help of page_to_phys() function and dma_map_resource()
provides physical address as is together with addition of DMA_ATTR_MMIO
attribute.

The old page-based API is preserved in mapping.c to ensure that existing
code won't be affected by changing EXPORT_SYMBOL to EXPORT_SYMBOL_GPL
variant for dma_*map_phys().

Reviewed-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Reviewed-by: default avatarKeith Busch <kbusch@kernel.org>
Signed-off-by: default avatarLeon Romanovsky <leonro@nvidia.com>
Signed-off-by: default avatarMarek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/54cc52af91777906bbe4a386113437ba0bcfba9c.1757423202.git.leonro@nvidia.com
parent bf0ecb3c

drivers/iommu/dma-iommu.c

+0 −14
Original line number Diff line number Diff line
@@ -1556,20 +1556,6 @@ void iommu_dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nents, 
		__iommu_dma_unmap(dev, start, end - start);

}



dma_addr_t iommu_dma_map_resource(struct device *dev, phys_addr_t phys,

		size_t size, enum dma_data_direction dir, unsigned long attrs)

{

	return __iommu_dma_map(dev, phys, size,

			dma_info_to_prot(dir, false, attrs) | IOMMU_MMIO,

			dma_get_mask(dev));

}



void iommu_dma_unmap_resource(struct device *dev, dma_addr_t handle,

		size_t size, enum dma_data_direction dir, unsigned long attrs)

{

	__iommu_dma_unmap(dev, handle, size);

}



static void __iommu_dma_free(struct device *dev, size_t size, void *cpu_addr)

{

	size_t alloc_size = PAGE_ALIGN(size);

include/linux/dma-direct.h

+0 −2
Original line number Diff line number Diff line
@@ -149,7 +149,5 @@ void dma_direct_free_pages(struct device *dev, size_t size, 
		struct page *page, dma_addr_t dma_addr,

		enum dma_data_direction dir);

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

dma_addr_t dma_direct_map_resource(struct device *dev, phys_addr_t paddr,

		size_t size, enum dma_data_direction dir, unsigned long attrs);



#endif /* _LINUX_DMA_DIRECT_H */

include/linux/dma-mapping.h

+13 −0
Original line number Diff line number Diff line
@@ -138,6 +138,10 @@ dma_addr_t dma_map_page_attrs(struct device *dev, struct page *page, 
		unsigned long attrs);

void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr, size_t size,

		enum dma_data_direction dir, unsigned long attrs);

dma_addr_t dma_map_phys(struct device *dev, phys_addr_t phys, size_t size,

		enum dma_data_direction dir, unsigned long attrs);

void dma_unmap_phys(struct device *dev, dma_addr_t addr, size_t size,

		enum dma_data_direction dir, unsigned long attrs);

unsigned int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg,

		int nents, enum dma_data_direction dir, unsigned long attrs);

void dma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg,
@@ -192,6 +196,15 @@ static inline void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr, 
		size_t size, enum dma_data_direction dir, unsigned long attrs)

{

}

static inline dma_addr_t dma_map_phys(struct device *dev, phys_addr_t phys,

		size_t size, enum dma_data_direction dir, unsigned long attrs)

{

	return DMA_MAPPING_ERROR;

}

static inline void dma_unmap_phys(struct device *dev, dma_addr_t addr,

		size_t size, enum dma_data_direction dir, unsigned long attrs)

{

}

static inline unsigned int dma_map_sg_attrs(struct device *dev,

		struct scatterlist *sg, int nents, enum dma_data_direction dir,

		unsigned long attrs)

include/linux/iommu-dma.h

+0 −4
Original line number Diff line number Diff line
@@ -42,10 +42,6 @@ size_t iommu_dma_opt_mapping_size(void); 
size_t iommu_dma_max_mapping_size(struct device *dev);

void iommu_dma_free(struct device *dev, size_t size, void *cpu_addr,

		dma_addr_t handle, unsigned long attrs);

dma_addr_t iommu_dma_map_resource(struct device *dev, phys_addr_t phys,

		size_t size, enum dma_data_direction dir, unsigned long attrs);

void iommu_dma_unmap_resource(struct device *dev, dma_addr_t handle,

		size_t size, enum dma_data_direction dir, unsigned long attrs);

struct sg_table *iommu_dma_alloc_noncontiguous(struct device *dev, size_t size,

		enum dma_data_direction dir, gfp_t gfp, unsigned long attrs);

void iommu_dma_free_noncontiguous(struct device *dev, size_t size,

include/trace/events/dma.h

+0 −2
Original line number Diff line number Diff line
@@ -73,7 +73,6 @@ DEFINE_EVENT(dma_map, name, \ 
	TP_ARGS(dev, phys_addr, dma_addr, size, dir, attrs))



DEFINE_MAP_EVENT(dma_map_phys);

DEFINE_MAP_EVENT(dma_map_resource);



DECLARE_EVENT_CLASS(dma_unmap,

	TP_PROTO(struct device *dev, dma_addr_t addr, size_t size,
@@ -111,7 +110,6 @@ DEFINE_EVENT(dma_unmap, name, \ 
	TP_ARGS(dev, addr, size, dir, attrs))



DEFINE_UNMAP_EVENT(dma_unmap_phys);

DEFINE_UNMAP_EVENT(dma_unmap_resource);



DECLARE_EVENT_CLASS(dma_alloc_class,

	TP_PROTO(struct device *dev, void *virt_addr, dma_addr_t dma_addr,