This commit adds code to supply variables required
to enable read affinity for rbd volumes.
It leverages `read_from_replica=localize,crush_locations=key:value`
krbd map option from ceph to serve reads from the most local OSD.
refer:
https://docs.ceph.com/en/latest/man/8/rbd/#kernel-rbd-krbd-options
Signed-off-by: Rakshith R <rar@redhat.com>
(cherry picked from commit 8b9ded1f77)
Rakshith R
21fa74f2d9