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I can still have the "order" parameter to > > > make the API cleaner (even if it'll be a pure overhead.. because all > > > existing caller will pass in PUD_SIZE as of now), > > > > That doesn't seem right, the callers should report the real value not > > artifically cap it.. Like ARM does have page sizes greater than PUD > > that might be interesting to enable someday for PFN users. > > It needs to pass in PUD_SIZE to match what vfio-pci currently supports in > its huge_fault(). Hm, OK that does make sense. I would add a small comment though as it is not so intuitive and may not apply to something using ioremap.. > So this will introduce a new file operation that will only be used so far > in VFIO, playing similar role until we start to convert many > get_unmapped_area() to this one. Yes, if someone wants to do a project here you can markup memfds/shmem/hugetlbfs/etc/etc to define their internal folio orders and hopefully ultimately remove some of that alignment logic from the arch code. Jason