What happens to mappings when closing file?

[olafBuddenhagen]

Hi,

I'm trying to understand why filesystem servers need proxy memory
objects for io_map(). Unfortunately, I don't have time to read all the
relevant code right now... After a quick glance, my guess is that the
proxy objects are used so the same pager can be provided to several
clients mapping the same file, but with different permissions?

But if several clients share a pager, doesn't that mean there is no way
to shut down an individual client's mapping when the client closes the
file?

-antrik-