This series introduces the ability for certain devices on s390 to bypass a layer of IOMMU via the iommu.passthrough=1 option. In order to enable this, the concept of an identity domain is added to s390-iommu. On s390, IOMMU passthrough is only allowed if indicated via a special bit in s390 CLP data for the associated device group, otherwise we must fall back to dma-iommu. Changes for v4: - Additional patch to handle IOAT registration within s390-iommu. This fixes an issue with re-registration of identity domain during events like zpci_hot_reset_device - Fixup page alignment for bus_dma_region setup - Dropped a few review/test tags due to above changes Changes for v3: - Rebase onto 6.13 - fixed bus_dma_region size (Niklas) Changes for v2: - Remove ARCH_HAS_PHYS_TO_DMA, use bus_dma_region - Remove use of def_domain_type, use 1 of 2 ops chosen at init Matthew Rosato (4): s390/pci: check for relaxed translation capability s390/pci: store DMA offset in bus_dma_region iommu/s390: handle IOAT registration based on domain iommu/s390: implement iommu passthrough via identity domain arch/s390/include/asm/pci.h | 4 +- arch/s390/include/asm/pci_clp.h | 4 +- arch/s390/kvm/pci.c | 17 +--- arch/s390/pci/pci.c | 35 ++++---- arch/s390/pci/pci_bus.c | 18 +++++ arch/s390/pci/pci_clp.c | 1 + arch/s390/pci/pci_sysfs.c | 11 +-- drivers/iommu/s390-iommu.c | 138 ++++++++++++++++++++++++++------ 8 files changed, 161 insertions(+), 67 deletions(-) -- 2.48.1