Commit e53d29f9 authored by Leon Romanovsky's avatar Leon Romanovsky Committed by Marek Szyprowski
Browse files

dma-mapping: convert dma_direct_*map_page to be phys_addr_t based 



Convert the DMA direct mapping functions to accept physical addresses
directly instead of page+offset parameters. The functions were already
operating on physical addresses internally, so this change eliminates
the redundant page-to-physical conversion at the API boundary.

The functions dma_direct_map_page() and dma_direct_unmap_page() are
renamed to dma_direct_map_phys() and dma_direct_unmap_phys() respectively,
with their calling convention changed from (struct page *page,
unsigned long offset) to (phys_addr_t phys).

Architecture-specific functions arch_dma_map_page_direct() and
arch_dma_unmap_page_direct() are similarly renamed to
arch_dma_map_phys_direct() and arch_dma_unmap_phys_direct().

The is_pci_p2pdma_page() checks are replaced with DMA_ATTR_MMIO checks
to allow integration with dma_direct_map_resource and dma_direct_map_phys()
is extended to support MMIO path either.

Reviewed-by: default avatarJason Gunthorpe <jgg@nvidia.com>
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/bb15a22f76dc2e26683333ff54e789606cfbfcf0.1757423202.git.leonro@nvidia.com
parent f9374de1

arch/powerpc/kernel/dma-iommu.c

+2 −2
Original line number Diff line number Diff line
@@ -14,7 +14,7 @@ 
#define can_map_direct(dev, addr) \

	((dev)->bus_dma_limit >= phys_to_dma((dev), (addr)))



bool arch_dma_map_page_direct(struct device *dev, phys_addr_t addr)

bool arch_dma_map_phys_direct(struct device *dev, phys_addr_t addr)

{

	if (likely(!dev->bus_dma_limit))

		return false;
@@ -24,7 +24,7 @@ bool arch_dma_map_page_direct(struct device *dev, phys_addr_t addr) 


#define is_direct_handle(dev, h) ((h) >= (dev)->archdata.dma_offset)



bool arch_dma_unmap_page_direct(struct device *dev, dma_addr_t dma_handle)

bool arch_dma_unmap_phys_direct(struct device *dev, dma_addr_t dma_handle)

{

	if (likely(!dev->bus_dma_limit))

		return false;

include/linux/dma-map-ops.h

+4 −4
Original line number Diff line number Diff line
@@ -395,15 +395,15 @@ void *arch_dma_set_uncached(void *addr, size_t size); 
void arch_dma_clear_uncached(void *addr, size_t size);



#ifdef CONFIG_ARCH_HAS_DMA_MAP_DIRECT

bool arch_dma_map_page_direct(struct device *dev, phys_addr_t addr);

bool arch_dma_unmap_page_direct(struct device *dev, dma_addr_t dma_handle);

bool arch_dma_map_phys_direct(struct device *dev, phys_addr_t addr);

bool arch_dma_unmap_phys_direct(struct device *dev, dma_addr_t dma_handle);

bool arch_dma_map_sg_direct(struct device *dev, struct scatterlist *sg,

		int nents);

bool arch_dma_unmap_sg_direct(struct device *dev, struct scatterlist *sg,

		int nents);

#else

#define arch_dma_map_page_direct(d, a)		(false)

#define arch_dma_unmap_page_direct(d, a)	(false)

#define arch_dma_map_phys_direct(d, a)		(false)

#define arch_dma_unmap_phys_direct(d, a)	(false)

#define arch_dma_map_sg_direct(d, s, n)		(false)

#define arch_dma_unmap_sg_direct(d, s, n)	(false)

#endif

kernel/dma/direct.c

+3 −3
Original line number Diff line number Diff line
@@ -448,7 +448,7 @@ void dma_direct_unmap_sg(struct device *dev, struct scatterlist *sgl, 
		if (sg_dma_is_bus_address(sg))

			sg_dma_unmark_bus_address(sg);

		else

			dma_direct_unmap_page(dev, sg->dma_address,

			dma_direct_unmap_phys(dev, sg->dma_address,

					      sg_dma_len(sg), dir, attrs);

	}

}
@@ -471,8 +471,8 @@ int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents, 
			 */

			break;

		case PCI_P2PDMA_MAP_NONE:

			sg->dma_address = dma_direct_map_page(dev, sg_page(sg),

					sg->offset, sg->length, dir, attrs);

			sg->dma_address = dma_direct_map_phys(dev, sg_phys(sg),

					sg->length, dir, attrs);

			if (sg->dma_address == DMA_MAPPING_ERROR) {

				ret = -EIO;

				goto out_unmap;

kernel/dma/direct.h

+36 −21
Original line number Diff line number Diff line
@@ -80,42 +80,57 @@ static inline void dma_direct_sync_single_for_cpu(struct device *dev, 
		arch_dma_mark_clean(paddr, size);

}



static inline dma_addr_t dma_direct_map_page(struct device *dev,

		struct page *page, unsigned long offset, size_t size,

		enum dma_data_direction dir, unsigned long attrs)

static inline dma_addr_t dma_direct_map_phys(struct device *dev,

		phys_addr_t phys, size_t size, enum dma_data_direction dir,

		unsigned long attrs)

{

	phys_addr_t phys = page_to_phys(page) + offset;

	dma_addr_t dma_addr = phys_to_dma(dev, phys);

	dma_addr_t dma_addr;



	if (is_swiotlb_force_bounce(dev)) {

		if (is_pci_p2pdma_page(page))

			return DMA_MAPPING_ERROR;

		if (attrs & DMA_ATTR_MMIO)

			goto err_overflow;



		return swiotlb_map(dev, phys, size, dir, attrs);

	}



	if (attrs & DMA_ATTR_MMIO) {

		dma_addr = phys;

		if (unlikely(!dma_capable(dev, dma_addr, size, false)))

			goto err_overflow;

	} else {

		dma_addr = phys_to_dma(dev, phys);

		if (unlikely(!dma_capable(dev, dma_addr, size, true)) ||

		    dma_kmalloc_needs_bounce(dev, size, dir)) {

		if (is_pci_p2pdma_page(page))

			return DMA_MAPPING_ERROR;

			if (is_swiotlb_active(dev))

				return swiotlb_map(dev, phys, size, dir, attrs);



		dev_WARN_ONCE(dev, 1,

			     "DMA addr %pad+%zu overflow (mask %llx, bus limit %llx).\n",

			     &dma_addr, size, *dev->dma_mask, dev->bus_dma_limit);

		return DMA_MAPPING_ERROR;

			goto err_overflow;

		}

	}



	if (!dev_is_dma_coherent(dev) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC))

	if (!dev_is_dma_coherent(dev) &&

	    !(attrs & (DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_MMIO)))

		arch_sync_dma_for_device(phys, size, dir);

	return dma_addr;



err_overflow:

	dev_WARN_ONCE(

		dev, 1,

		"DMA addr %pad+%zu overflow (mask %llx, bus limit %llx).\n",

		&dma_addr, size, *dev->dma_mask, dev->bus_dma_limit);

	return DMA_MAPPING_ERROR;

}



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

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

		size_t size, enum dma_data_direction dir, unsigned long attrs)

{

	phys_addr_t phys = dma_to_phys(dev, addr);

	phys_addr_t phys;



	if (attrs & DMA_ATTR_MMIO)

		/* nothing to do: uncached and no swiotlb */

		return;



	phys = dma_to_phys(dev, addr);

	if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))

		dma_direct_sync_single_for_cpu(dev, addr, size, dir);

kernel/dma/mapping.c

+4 −4
Original line number Diff line number Diff line
@@ -166,8 +166,8 @@ dma_addr_t dma_map_page_attrs(struct device *dev, struct page *page, 
		return DMA_MAPPING_ERROR;



	if (dma_map_direct(dev, ops) ||

	    arch_dma_map_page_direct(dev, phys + size))

		addr = dma_direct_map_page(dev, page, offset, size, dir, attrs);

	    arch_dma_map_phys_direct(dev, phys + size))

		addr = dma_direct_map_phys(dev, phys, size, dir, attrs);

	else if (use_dma_iommu(dev))

		addr = iommu_dma_map_phys(dev, phys, size, dir, attrs);

	else
@@ -187,8 +187,8 @@ void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr, size_t size, 


	BUG_ON(!valid_dma_direction(dir));

	if (dma_map_direct(dev, ops) ||

	    arch_dma_unmap_page_direct(dev, addr + size))

		dma_direct_unmap_page(dev, addr, size, dir, attrs);

	    arch_dma_unmap_phys_direct(dev, addr + size))

		dma_direct_unmap_phys(dev, addr, size, dir, attrs);

	else if (use_dma_iommu(dev))

		iommu_dma_unmap_phys(dev, addr, size, dir, attrs);

	else