Updated openstack/openstack
Project: openstack/cinder  408c764f4fac26dee250d6c48454aab930b18b2a

GlusterFS: Lock on a per-volume basis

This allows operations that do not conflict with each
other (i.e. are on different volumes) to run concurrently.
The prior locking scheme was too coarse and essentially
made the driver single-threaded.

Change-Id: Ib048c21f66926cb96ae02ced4bd16a752d52b301