marked nfs41_name_cache_insert() parameters fh and info as OPTIONAL; passing NULL designates a negative lookup entry
name_cache_entry_create() no longer calls attr_cache_find_or_create(), and doesn't need the 'fileid' argument
name_cache_entry_update() also makes fh and info OPTIONAL, and handles the cases where we switch from a negative <-> positive entry, calling attr_cache_find_or_create() or attr_cache_entry_deref() as appropriate
removed unused function name_cache_find_or_create(); everything uses name_cache_entry_find_or_create() instead, so renamed that to name_cache_find_or_create()
Signed-off-by: Casey Bodley <cbodley@umich.edu>
added function entry_invis() in addition to entry_has_expired(). entry_invis() returns true if entry_has_expired() or for negative entries. the is_negative flag is set for negative entries (defined as having entry->attributes == NULL), and returned by nfs41_name_cache_lookup(). when nfs41_lookup() sees this flag set, it returns the status without attempting to do any more lookups
Signed-off-by: Casey Bodley <cbodley@umich.edu>
