diff options
| author | Leon Romanovsky <leonro@nvidia.com> | 2025-09-09 16:27:34 +0300 |
|---|---|---|
| committer | Marek Szyprowski <m.szyprowski@samsung.com> | 2025-09-12 00:18:20 +0200 |
| commit | f9374de14c0e8c36cfb7c68618c07cb155e6f8e6 (patch) | |
| tree | dfa567ebebde40dfcb6d9a01bae55e8d44d4c362 | |
| parent | 513559f73700966ded094b090c3ecc6dff877ef9 (diff) | |
iommu/dma: implement DMA_ATTR_MMIO for iommu_dma_(un)map_phys()
Make iommu_dma_map_phys() and iommu_dma_unmap_phys() respect
DMA_ATTR_MMIO.
DMA_ATTR_MMIO makes the functions behave the same as
iommu_dma_(un)map_resource():
- No swiotlb is possible
- No cache flushing is done (ATTR_MMIO should not be cached memory)
- prot for iommu_map() has IOMMU_MMIO not IOMMU_CACHE
This is preparation for replacing iommu_dma_map_resource() callers
with iommu_dma_map_phys(DMA_ATTR_MMIO) and removing
iommu_dma_(un)map_resource().
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/acc255bee358fec9c7da6b2a5904ee50abcd09f1.1757423202.git.leonro@nvidia.com
| -rw-r--r-- | drivers/iommu/dma-iommu.c | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index aea119f32f96..6804aaf034a1 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -1211,16 +1211,19 @@ dma_addr_t iommu_dma_map_phys(struct device *dev, phys_addr_t phys, size_t size, */ if (dev_use_swiotlb(dev, size, dir) && iova_unaligned(iovad, phys, size)) { + if (attrs & DMA_ATTR_MMIO) + return DMA_MAPPING_ERROR; + phys = iommu_dma_map_swiotlb(dev, phys, size, dir, attrs); if (phys == (phys_addr_t)DMA_MAPPING_ERROR) return DMA_MAPPING_ERROR; } - if (!coherent && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + if (!coherent && !(attrs & (DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_MMIO))) arch_sync_dma_for_device(phys, size, dir); iova = __iommu_dma_map(dev, phys, size, prot, dma_mask); - if (iova == DMA_MAPPING_ERROR) + if (iova == DMA_MAPPING_ERROR && !(attrs & DMA_ATTR_MMIO)) swiotlb_tbl_unmap_single(dev, phys, size, dir, attrs); return iova; } @@ -1228,10 +1231,14 @@ dma_addr_t iommu_dma_map_phys(struct device *dev, phys_addr_t phys, size_t size, void iommu_dma_unmap_phys(struct device *dev, dma_addr_t dma_handle, size_t size, enum dma_data_direction dir, unsigned long attrs) { - struct iommu_domain *domain = iommu_get_dma_domain(dev); phys_addr_t phys; - phys = iommu_iova_to_phys(domain, dma_handle); + if (attrs & DMA_ATTR_MMIO) { + __iommu_dma_unmap(dev, dma_handle, size); + return; + } + + phys = iommu_iova_to_phys(iommu_get_dma_domain(dev), dma_handle); if (WARN_ON(!phys)) return; |