From f7326196a781622b33bfbdabb00f5e72b5fb5679 Mon Sep 17 00:00:00 2001 From: Leon Romanovsky Date: Tue, 9 Sep 2025 16:27:39 +0300 Subject: 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: Jason Gunthorpe Reviewed-by: Keith Busch Signed-off-by: Leon Romanovsky Signed-off-by: Marek Szyprowski Link: https://lore.kernel.org/r/54cc52af91777906bbe4a386113437ba0bcfba9c.1757423202.git.leonro@nvidia.com --- include/linux/dma-mapping.h | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'include/linux/dma-mapping.h') diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index 4254fd9bdf5d..8248ff9363ee 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -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) -- cgit v1.2.3