On 4/29/22 09:28, Tian, Kevin wrote: >> From: Joao Martins <joao.m.martins@xxxxxxxxxx> >> Sent: Friday, April 29, 2022 5:09 AM >> >> Similar to .read_and_clear_dirty() use the page table >> walker helper functions and set DBM|RDONLY bit, thus >> switching the IOPTE to writeable-clean. > > this should not be one-off if the operation needs to be > applied to IOPTE. Say a map request comes right after > set_dirty_tracking() is called. If it's agreed to remove > the range op then smmu driver should record the tracking > status internally and then apply the modifier to all the new > mappings automatically before dirty tracking is disabled. > Otherwise the same logic needs to be kept in iommufd to > call set_dirty_tracking_range() explicitly for every new > iopt_area created within the tracking window. Gah, I totally missed that by mistake. New mappings aren't carrying over the "DBM is set". This needs a new io-pgtable quirk added post dirty-tracking toggling. I can adjust, but I am at odds on including this in a future iteration given that I can't really test any of this stuff. Might drop the driver until I have hardware/emulation I can use (or maybe others can take over this). It was included for revising the iommu core ops and whether iommufd was affected by it. I'll delete the range op, and let smmu v3 driver walk its own IO pgtables.
