[PATCH 0/8] dma-mapping: migrate to physical address-based API

Leon Romanovsky leon at kernel.org
Wed Jun 25 23:18:57 AEST 2025


This series refactors the DMA mapping to use physical addresses
as the primary interface instead of page+offset parameters. This
change aligns the DMA API with the underlying hardware reality where
DMA operations work with physical addresses, not page structures.

The series consists of 8 patches that progressively convert the DMA
mapping infrastructure from page-based to physical address-based APIs:

The series maintains backward compatibility by keeping the old
page-based API as wrapper functions around the new physical
address-based implementations.

Thanks

Leon Romanovsky (8):
  dma-debug: refactor to use physical addresses for page mapping
  dma-mapping: rename trace_dma_*map_page to trace_dma_*map_phys
  iommu/dma: rename iommu_dma_*map_page to iommu_dma_*map_phys
  dma-mapping: convert dma_direct_*map_page to be phys_addr_t based
  kmsan: convert kmsan_handle_dma to use physical addresses
  dma-mapping: fail early if physical address is mapped through platform
    callback
  dma-mapping: export new dma_*map_phys() interface
  mm/hmm: migrate to physical address-based DMA mapping API

 Documentation/core-api/dma-api.rst |  4 +-
 arch/powerpc/kernel/dma-iommu.c    |  4 +-
 drivers/iommu/dma-iommu.c          | 14 +++----
 drivers/virtio/virtio_ring.c       |  4 +-
 include/linux/dma-map-ops.h        |  8 ++--
 include/linux/dma-mapping.h        | 13 ++++++
 include/linux/iommu-dma.h          |  7 ++--
 include/linux/kmsan.h              | 12 +++---
 include/trace/events/dma.h         |  4 +-
 kernel/dma/debug.c                 | 28 ++++++++-----
 kernel/dma/debug.h                 | 16 ++++---
 kernel/dma/direct.c                |  6 +--
 kernel/dma/direct.h                | 13 +++---
 kernel/dma/mapping.c               | 67 +++++++++++++++++++++---------
 kernel/dma/ops_helpers.c           |  6 +--
 mm/hmm.c                           |  8 ++--
 mm/kmsan/hooks.c                   | 36 ++++++++++++----
 tools/virtio/linux/kmsan.h         |  2 +-
 18 files changed, 159 insertions(+), 93 deletions(-)

-- 
2.49.0



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