Merge tag 'dma-mapping-6.18-2025-11-27' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux

Pull dma-mapping fixes from Marek Szyprowski:
 "Two last minute fixes for the recently modified DMA API infrastructure:

   - proper handling of DMA_ATTR_MMIO in dma_iova_unlink() function (me)

   - regression fix for the code refactoring related to P2PDMA (Pranjal
     Shrivastava)"

* tag 'dma-mapping-6.18-2025-11-27' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux:
  dma-direct: Fix missing sg_dma_len assignment in P2PDMA bus mappings
  iommu/dma: add missing support for DMA_ATTR_MMIO for dma_iova_unlink()

Author: torvalds

drivers/iommu/dma-iommu.c

@@ -2008,7 +2008,7 @@ static void iommu_dma_iova_unlink_range_slow(struct device *dev,
 			end - addr, iovad->granule - iova_start_pad);
 
 		if (!dev_is_dma_coherent(dev) &&
-		    !(attrs & DMA_ATTR_SKIP_CPU_SYNC))
+		    !(attrs & (DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_MMIO)))
 			arch_sync_dma_for_cpu(phys, len, dir);
 
 		swiotlb_tbl_unmap_single(dev, phys, len, dir, attrs);
@@ -2032,7 +2032,8 @@ static void __iommu_dma_iova_unlink(struct device *dev,
 	size_t unmapped;
 
 	if ((state->__size & DMA_IOVA_USE_SWIOTLB) ||
-	    (!dev_is_dma_coherent(dev) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)))
+	    (!dev_is_dma_coherent(dev) &&
+	     !(attrs & (DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_MMIO))))
 		iommu_dma_iova_unlink_range_slow(dev, addr, size, dir, attrs);
 
 	iommu_iotlb_gather_init(&iotlb_gather);

kernel/dma/direct.c

@@ -481,6 +481,7 @@ int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
 		case PCI_P2PDMA_MAP_BUS_ADDR:
 			sg->dma_address = pci_p2pdma_bus_addr_map(&p2pdma_state,
 					sg_phys(sg));
+			sg_dma_len(sg) = sg->length;
 			sg_dma_mark_bus_address(sg);
 			continue;
 		default: