On Fri, Apr 21, 2023 at 02:59:37PM -0300, Jason Gunthorpe wrote: > On Fri, Apr 21, 2023 at 10:37:22AM -0700, Nicolin Chen wrote: > > > How about the following piece? Needs a test with QEMU though.. > > > > static const size_t iommufd_device_data_size[] = { > > [IOMMU_HW_INFO_TYPE_NONE] = 0, > > [IOMMU_HW_INFO_TYPE_INTEL_VTD] = 0, > > [IOMMU_HW_INFO_TYPE_ARM_SMMUV3] = > > sizeof(struct iommu_device_data_arm_smmuv3), > > }; > > If we need more than one of these things we'll need a better > solution.. How about adding ops->device_data_size to store the value? And, since we have a few size arrays in hw_pagetable.c too, perhaps a new structure in ops packing all these sizes can clean up a bit things too? For example, static struct iommu_user_data_size arm_smmu_user_data_size = { .device_data_size = sizeof(iommu_device_data_arm_smmuv3), .hwpt_alloc_data_size = sizeof(iommu_hwpt_alloc_arm_smmuv3), .hwpt_invalidate_data_size = sizeof(iommu_hwpt_invalidate_arm_smmuv3), } The hwpt_xxx_data_size might be in form of arrays for multi- HWPT_TYPE support. > > rc = ops->set_dev_data_user(idev->dev, data); > > Where will the iommu driver store the vsid to sid xarray from these > arguments? The ARM structure packs a vsid. For example: static int arm_smmu_set_data(struct device *dev, const void *user_data) { const struct iommufd_device_data_arm_smmuv3 *data = user_data; struct arm_smmu_master *master = dev_iommu_priv_get(dev); struct arm_smmu_stream *stream = &master->streams[0]; struct arm_smmu_device *smmu = master->smmu; u32 sid_user = data->sid; int ret = 0; if (!sid_user) return -EINVAL; ret = xa_alloc(&smmu->streams_user, &sid_user, stream, XA_LIMIT(sid_user, sid_user), GFP_KERNEL_ACCOUNT); if (ret) return ret; stream->id_user = sid_user; return 0; } Thanks Nic