This requirement originates from the VT-d vfio series: https://lists.nongnu.org/archive/html/qemu-devel/2017-01/msg03495.html
The goal of this series is to allow IOMMU to notify unmap with very big IOTLB range, for example, with base=0 and size=2^63-1 (to unmap the whole address space). The first patch is a good to have, for traces. The second one is a cleanup of existing code, only. The third one moves the further RAM translation and check into map operation logic, so that it'll free unmap operations. The series is marked as RFC since I am not sure whether this is a workable way. Anyway, please review to help confirm it. Thanks. Peter Xu (3): vfio: trace map/unmap for notify as well vfio: introduce vfio_get_vaddr() vfio: allow to notify unmap for very large region hw/vfio/common.c | 56 ++++++++++++++++++++++++++++++++++------------------ hw/vfio/trace-events | 2 +- 2 files changed, 38 insertions(+), 20 deletions(-) -- 2.7.4