3PAR connection cache is in the wrong location

[Anthony Lee]

The 3PAR connection name cache is currently located in 3PAR common. It would be better if this was stored in a more global location since the cache in common could potentially be erased (cinder is restarted, common object destroyed). By doing this the drivers can keep track of the cache without needing to call another class.

Another solution is to not save the cache in 3PAR common and requery the backend to see if a host is already active.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/140197
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=9c50182b4a2ea86a305c5d33ec767340574a522e
Submitter: Jenkins
Branch: master

commit 9c50182b4a2ea86a305c5d33ec767340574a522e
Author: Anthony Lee <email address hidden>
Date: Mon Dec 8 17:12:27 2014 -0800

    Fixing 3PAR connection name cache error

    The 3PAR driver had a connection name cache in 3PAR common. If
    Cinder was restarted or the common object was destroyed the cache
    was lost. Instead of having the cache in 3PAR common, the 3PAR
    driver can query the backend to see if there is a host already
    available. Replacing the name cache with a backend query had minimal
    impact on performance of the driver and eliminates the problem of the
    cache being destroyed/lost.

    Closes-Bug: #1398914
    Change-Id: Ie5467abc38946cceb4896fe9cbbd1606c7fbfba2