s390/pci_dma: fix DMA table corruption with > 4 TB main memory
DMA addresses returned from map_page() are calculated by using an iommu
bitmap plus a start_dma offset. The size of this bitmap is based on the main
memory size. If we have more than (4 TB - start_dma) main memory, the DMA
address calculation will also produce addresses > 4 TB. Such addresses
cannot be inserted in the 3-level DMA page table, instead the entries
modulo 4 TB will be overwritten.
Fix this by restricting the iommu bitmap size to (4 TB - start_dma).
Also set zdev->end_dma to the actual end address of the usable
range, instead of the theoretical maximum as reported by the hardware,
which fixes a sanity check in dma_map() and also the IOMMU API domain
geometry aperture calculation.
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c
index 7ef12a3..11d4f27 100644
--- a/arch/s390/pci/pci.c
+++ b/arch/s390/pci/pci.c
@@ -701,8 +701,7 @@
goto out;
zpci_map_resources(pdev);
- zpci_register_ioat(zdev, 0, zdev->start_dma + PAGE_OFFSET,
- zdev->start_dma + zdev->iommu_size - 1,
+ zpci_register_ioat(zdev, 0, zdev->start_dma, zdev->end_dma,
(u64) zdev->dma_table);
out: