All directory accesses must be made with NFS_DIRBLKSIZE chunks to avoid

All directory accesses must be made with NFS_DIRBLKSIZE chunks to avoid
confusing the directory read cookie cache.  The nfs_access implementation
for v2 mounts attempts to read from the directory if root is the user
so that root can't access cached files when the server remaps root
to some other user.

Submitted by:	Doug Rabson <dfr@nlsystems.com>
Reviewed by:	Matthew Dillon <dillon@apollo.backplane.com>