In this commit
aaadb48d486cc880 vfs: keep virtual directory status accurate and reduce deadlock potential
We reworked the virtual directory detection to use an atomic bool so
that we could run part of the cache forgetting only with a read lock.
Unfortunately this had a bug which meant that directories with virtual
items could be forgotten.
This commit changes the boolean into a count of virtual entries which
should be more accurate.
Fixes#8082
6091a0362b