Cloned from launchpad blueprint https://blueprints.launchpad.net/cinder/+spec/retype-hp-3par.
Add retype support to the HP 3PAR driver. The driver will modify the volume's current userCPG, snapCPG provisioningType, and QOS settings, as needed, to make the volume behave appropriately for the new type. The existing retype framework handles what to do if the driver cannot retype (when it returns False or raises an exception).
The combination of optional type-specified VV set, old-style scoped extra-specs and QOS-specs will be resolved using existing code. So no new interpretation of a mixed-up type specifications will be introduced (no need to re-document these driver caveats).
Other than the usual validity checking, the 3PAR retype will have one limitation. Retype will not be allowed if the volume has snapshots and the retype would require modifying/tuning the snapCPG or userCPG.
Specification URL (additional information):
This bug has been closed as a part of the RHEL-OSP 6 general availability release. For details, see https://rhn.redhat.com/errata/rhel7-rhos-6-errata.html