Comment 8 for bug 1501670

Reviewed: https://review.openstack.org/260089
Committed: https://git.openstack.org/cgit/openstack/manila/commit/?id=bd9fef73daa329380675dee0485716ba2fdc0dff
Submitter: Jenkins
Branch: stable/liberty

commit bd9fef73daa329380675dee0485716ba2fdc0dff
Author: Csaba Henk <email address hidden>
Date: Thu Oct 8 02:27:37 2015 +0200

    glusterfs/volume layout: indicate volume usage on volumes themselves

    With volume layout, share-volume association was kept solely
    in the manila DB. That is not robust enough, first and
    foremost because upon starting the service, the manager
    will indicate existing share associations only of those
    volumes whose shares is in 'available' state.

    We need to know though if a volume is in a pristine state or
    not, regardless of the state of their shares. To this end,
    we introduce the 'user.manila-share' GlusterFS volume option
    to indicate manila share association -- made possible by
    GlusterFS allowing any user defined option to exist in the
    'user' option name space --, which indicator remains there
    until we explicitely drop it in `delete_share`. (The value
    of 'user.manila-share' is the id of the share owning the
    volume).

    As a beneficial side effect, this change will also provide
    insight to the Gluster storage admin about usage of the
    Manila volume pool.

    Change-Id: Icb388fd31fb6a992bee7e731f5e84403d5fd1a85
    Partial-Bug: #1501670
    (cherry picked from commit 3537be25165e96a44254b66f13ea508f60f57af0)