Detect when no more mappers


I’m pretty sure the answer to this is no, but I will ask anyway.

Is there anyway to know (other than polling using MmCanFileBeTruncated) when there are no more file mappers?

I can determine when a mapping is created via IRP_MJ_ACQUIRE_FOR_SECTION_SYNC but as far as I can determine there is way to know when mapping handles have been closed (since Mm may choose to keep the data section around to re-use, thus keeping a FILE_OBJECT alive) via callback.