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-direct.h | 2 -- include/linux/dma-mapping.h | 13 +++++++++++++ include/linux/iommu-dma.h | 4 ---- 3 files changed, 13 insertions(+), 6 deletions(-) (limited to 'include/linux') diff --git a/include/linux/dma-direct.h b/include/linux/dma-direct.h index f3bc0bcd7098..c249912456f9 100644 --- a/include/linux/dma-direct.h +++ b/include/linux/dma-direct.h @@ -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 */ 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) diff --git a/include/linux/iommu-dma.h b/include/linux/iommu-dma.h index 485bdffed988..a92b3ff9b934 100644 --- a/include/linux/iommu-dma.h +++ b/include/linux/iommu-dma.h @@ -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, -- cgit v1.2.3