On Mon, Aug 04, 2025 at 10:09:44PM +0200, Mahmoud Nagy Adam wrote: > > We should be able to convert to a maple tree without introducing these > > "legacy" ops. > > This technically be done directly by changing the current ops (ioctl, > mmap, read & write) to add vmmap argument in place and call the ops with > NULL for vmmap entry if the entry not found in the mt You have gone very far away from my original suggestion: https://lore.kernel.org/kvm/20250716184028.GA2177603@xxxxxxxx/ map2 should not exist, once you introduced a vfio_mmap_ops for free then the mmap op should be placed into that structure. ioctl2 is nasty, that should be the "new function op for VFIO_DEVICE_GET_REGION_INFO" instead. We have been slowly moving towards the core code doing more decode and dispatch of ioctls instead of duplicating in drivers. I still stand by the patch plan I gave in the above email. Clean up how VFIO_DEVICE_GET_REGION_INFO is handled by drivers and a maple tree change will trivially drop on top. The basic way you've used the maple tree here looks plausible, but I'm still against some VFIO_DEVICE_SET_MMAP_ATTRS as a uapi. mmap cookies should be immutable, once they are issued they are for a certain thing and never change. The entire point of all this infrastructure is to allow more mmap cookies to be issued. The new UAPI should be some 'VFIO_DEVICE_GET_REGION_INFO2' or whatever that generates an entirely new mmap cookie with write combining semantics. Jason
