Issue: When parallel-readdir is enabled, readdir-optimize automatically stops working because of a bug in rda_opendir. RCA: In rda_opendir, the xattrs that indicate readdir-optimize or not is sent in xdata. This xdata is sent to all the readdirp prefetch calls. A dict_ref is taken on xdata and kept in rda_opendir to be used by rda_fill_fd, but dht_opendir deletes some elements in xdata after calling rda_opendir. Hence dict_ref is not a right choice here, dict_copy needs to used. Change-Id: Ie7cc7ceb03117dd4179ef7905647f2f123f94966 fixes: bz#1578650 Signed-off-by: Poornima G <pgurusid@redhat.com>