storwize SVC driver fails to map volume to host when SCSI IDs are not contiguous

[Alan Jiang]

When multiple cinder volumes are attached to VM and detach/deleted in a different order
of creation/attatch, the SCSI ID for vdisk mapping may not be contiguous any more. The _map_vol_to_host()
function in storwize_driver.py may map a vdisk with an in-use SCSI ID which will cause nova
volume-attach to fail.

In the case of existing vdisk host mapping with the following SCSI ID: [0,1,2,3,4,5,7,8],
_map_vol_to_host() will use SCSI ID 7 to map a vdisk to host. It failed the mkvdiskhostmap command:

Command: mkvdiskhostmap -host b02 -scsi 7 vol-b629539b-fac5-4382-b6bd-3e639df2ee43
Exit code: 1
Stdout: ''
Stderr: 'CMMVC5879E The VDisk-to-host mapping was not created because a VDisk is already mapped to this host with this SCSI LUN

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/24761

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/24761
Committed: http://github.com/openstack/cinder/commit/e0878c86207d5ff5c2ebaa69eac454af545925ef
Submitter: Jenkins
Branch: master

commit e0878c86207d5ff5c2ebaa69eac454af545925ef
Author: Avishay Traeger <email address hidden>
Date: Tue Mar 19 09:42:06 2013 +0200

    Fix Storwize/SVC LUN allocation with holes.

    The Storwize/SVC driver should find the first unused LUN, but
    continues searching, returning erroneous results. Added 'break'
    statement to fix.

    Change-Id: Ibd95714e086a513a39fe9d20ffec57135dc5ec55
    Fixes: bug 1157012

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: milestone-proposed
Review: https://review.openstack.org/25097

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/25097
Committed: http://github.com/openstack/cinder/commit/9ff5bf692e09bfadd9ed10eeec8160af4d2662a6
Submitter: Jenkins
Branch: milestone-proposed

commit 9ff5bf692e09bfadd9ed10eeec8160af4d2662a6
Author: Avishay Traeger <email address hidden>
Date: Tue Mar 19 09:42:06 2013 +0200

    Fix Storwize/SVC LUN allocation with holes.

    The Storwize/SVC driver should find the first unused LUN, but
    continues searching, returning erroneous results. Added 'break'
    statement to fix.

    Change-Id: Ibd95714e086a513a39fe9d20ffec57135dc5ec55
    Fixes: bug 1157012
    (cherry picked from commit e0878c86207d5ff5c2ebaa69eac454af545925ef)