Hey, This patchset moves IOMMU_DOMAIN_DMA iommu domain management to iommu.c. This avoids the use of find_or_alloc_domain whose domain assignment is inconsistent with the iommu grouping as determined by pci_device_group.
Patch 3 permits domain type IOMMU_DOMAIN_DMA to be allocated via the iommu_ops api, allowing the default_domain of an iommu group to be set in iommu.c. This domain will be attached to every device that is brought up with an iommu group, and the devices reserved regions will be mapped using regions returned by get_resv_regions. In intel_iommu_domain_alloc we don’t know the IOMMU this domain will be associated with so we defer full initialisation until intel_iommu_attach_device. Currently iommu.c:iommu_group_add_device will try to map a devices reserved regions before attaching the domain which would cause issue if the domain is not fully initialised. This is addressed in patch 1 by moving the mapping to after attaching. Patch 2 implements function apply_resv_region, used in iommu_group_create_direct_mappings to mark the reserved regions as non mappable for the dma_map_ops api. Patch 4 removes the domain lazy allocation logic. Before this patch the lazy allocation logic would not be used as any domain allocated using these paths would be replaced when attaching the group default domain. Default domain allocation has been tested with and without this patch on 4.19. Cheers, James. James Sewart (4): iommu: Move iommu_group_create_direct_mappings to after device_attach iommu/vt-d: Implement apply_resv_region for reserving IOVA ranges iommu/vt-d: Allow IOMMU_DOMAIN_DMA and IOMMU_DOMAIN_IDENTITY to be allocated iommu/vt-d: Remove lazy allocation of domains drivers/iommu/intel-iommu.c | 329 ++++++++++++------------------------ drivers/iommu/iommu.c | 4 +- 2 files changed, 108 insertions(+), 225 deletions(-) -- 2.17.1
