STABLE12-linux-dcache-create-negative-dentries-22-needs-while-still-avoiding-vlru...

STABLE12-linux-dcache-create-negative-dentries-22-needs-while-still-avoiding-vlru-cycle-20020328

based on patch by Srikanth Vishwanathan and modifications based on suggestions
from Ted Anderson applicable to this part of the code.

the original theory we operated under, namely that negative dentries
could be banished entirely, causes file creation to stop working
under linux 2.2 kernels. reverting that change means we have to deal with
these negative dentries, and Srikanth's original suggested patch does so.

(cherry picked from commit 4beb9adb661bade7caff8adf40ecb3882ae7deac)