kernel/linux.git/include/linux/dma-map-ops.h, branch v6.19.11

dma-mapping: remove unused map_page callback

2025-10-29T09:27:31+00:00

After conversion of arch code to use physical address mapping, there are no users of .map_page() and .unmap_page() callbacks, so let's remove them. Reviewed-by: Jason Gunthorpe Signed-off-by: Leon Romanovsky Signed-off-by: Marek Szyprowski Link: https://lore.kernel.org/r/20251015-remove-map-page-v5-14-3bbfe3a25cdf@kernel.org

dma-mapping: remove unused mapping resource callbacks

2025-10-29T09:27:30+00:00

After ARM and XEN conversions to use physical addresses for the mapping, there are no in-kernel users for map_resource/unmap_resource callbacks, so remove them. Reviewed-by: Jason Gunthorpe Signed-off-by: Leon Romanovsky Signed-off-by: Marek Szyprowski Link: https://lore.kernel.org/r/20251015-remove-map-page-v5-6-3bbfe3a25cdf@kernel.org

dma-mapping: prepare dma_map_ops to conversion to physical address

2025-10-29T09:27:29+00:00

Add new .map_phys() and .unmap_phys() callbacks to dma_map_ops as a preparation to replace .map_page() and .unmap_page() respectively. Reviewed-by: Jason Gunthorpe Signed-off-by: Leon Romanovsky Signed-off-by: Marek Szyprowski Link: https://lore.kernel.org/r/20251015-remove-map-page-v5-1-3bbfe3a25cdf@kernel.org

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

2025-09-11T22:18:20+00:00

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: Jason Gunthorpe Signed-off-by: Leon Romanovsky Signed-off-by: Marek Szyprowski Link: https://lore.kernel.org/r/bb15a22f76dc2e26683333ff54e789606cfbfcf0.1757423202.git.leonro@nvidia.com

of: reserved_mem: Restructure call site for dma_contiguous_early_fixup()

2025-08-11T11:05:38+00:00

Restructure the call site for dma_contiguous_early_fixup() to where the reserved_mem nodes are being parsed from the DT so that dma_mmu_remap[] is populated before dma_contiguous_remap() is called. Fixes: 8a6e02d0c00e ("of: reserved_mem: Restructure how the reserved memory regions are processed") Signed-off-by: Oreoluwa Babatunde Tested-by: William Zhang Signed-off-by: Marek Szyprowski Link: https://lore.kernel.org/r/20250806172421.2748302-1-oreoluwa.babatunde@oss.qualcomm.com

dma-mapping: move the PCI P2PDMA mapping helpers to pci-p2pdma.h

2025-05-06T06:36:53+00:00

To support the upcoming non-scatterlist mapping helpers, we need to go back to have them called outside of the DMA API. Thus move them out of dma-map-ops.h, which is only for DMA API implementations to pci-p2pdma.h, which is for driver use. Note that the core helper is still not exported as the mapping is expected to be done only by very highlevel subsystem code at least for now. Signed-off-by: Christoph Hellwig Reviewed-by: Logan Gunthorpe Acked-by: Bjorn Helgaas Tested-by: Jens Axboe Reviewed-by: Luis Chamberlain Reviewed-by: Lu Baolu Signed-off-by: Leon Romanovsky Signed-off-by: Marek Szyprowski

PCI/P2PDMA: Refactor the p2pdma mapping helpers

2025-05-06T06:36:53+00:00

The current scheme with a single helper to determine the P2P status and map a scatterlist segment force users to always use the map_sg helper to DMA map, which we're trying to get away from because they are very cache inefficient. Refactor the code so that there is a single helper that checks the P2P state for a page, including the result that it is not a P2P page to simplify the callers, and a second one to perform the address translation for a bus mapped P2P transfer that does not depend on the scatterlist structure. Signed-off-by: Christoph Hellwig Reviewed-by: Logan Gunthorpe Acked-by: Bjorn Helgaas Tested-by: Jens Axboe Reviewed-by: Luis Chamberlain Reviewed-by: Lu Baolu Signed-off-by: Leon Romanovsky Signed-off-by: Marek Szyprowski

dma-mapping: remove an outdated comment from dma-map-ops.h

2024-10-29T07:53:37+00:00

The "/* CONFIG_ARCH_HAS_DMA_COHERENCE_H */" was an description about the ARCH_HAS_DMA_COHERENCE_H configure option, but it has been removed since the dma_default_coherent variable was lifted from the mips architecture to the driver core. Therefore it doesn't match any compile guard now. Just remove it. Fixes: 6d4e9a8efe3d ("driver core: lift dma_default_coherent into common code") Signed-off-by: Sui Jingfeng Signed-off-by: Christoph Hellwig

dma-mapping: fix vmap and mmap of noncontiougs allocations

2024-09-22T16:47:51+00:00

Commit b5c58b2fdc42 ("dma-mapping: direct calls for dma-iommu") switched to use direct calls to dma-iommu, but missed the dma_vmap_noncontiguous, dma_vunmap_noncontiguous and dma_mmap_noncontiguous behavior keyed off the presence of the alloc_noncontiguous method. Fix this by removing the now unused alloc_noncontiguous and free_noncontiguous methods and moving the vmapping and mmaping of the noncontiguous allocations into the iommu code, as it is the only provider of actually noncontiguous allocations. Fixes: b5c58b2fdc42 ("dma-mapping: direct calls for dma-iommu") Reported-by: Xi Ruoyao Signed-off-by: Christoph Hellwig Reviewed-by: Leon Romanovsky Tested-by: Xi Ruoyao

dma-mapping: clearly mark DMA ops as an architecture feature

2024-09-04T04:08:51+00:00

DMA ops are a helper for architectures and not for drivers to override the DMA implementation. Unfortunately driver authors keep ignoring this. Make the fact more clear by renaming the symbol to ARCH_HAS_DMA_OPS and having the two drivers overriding their dma_ops depend on that. These drivers should probably be marked broken, but we can give them a bit of a grace period for that. Signed-off-by: Christoph Hellwig Reviewed-by: Thomas Gleixner Acked-by: Sakari Ailus # for IPU6 Acked-by: Robin Murphy