Revert resize does not delete instance directory with Ceph

[Feodor Tersin]

Resize revertion leaves instance directory on the second host with Ceph image backend. As the result the second attempt to resize the instance to the same host fails with n-cpu.log:

Traceback (most recent call last):
  File "/opt/stack/nova/nova/compute/manager.py", line 3942, in finish_resize
    disk_info, image_meta)
  File "/opt/stack/nova/nova/compute/manager.py", line 3907, in _finish_resize
    old_instance_type)
  File "/usr/lib/python2.7/site-packages/oslo_utils/excutils.py", line 220, in __exit__
    self.force_reraise()
  File "/usr/lib/python2.7/site-packages/oslo_utils/excutils.py", line 196, in force_reraise
    six.reraise(self.type_, self.value, self.tb)
  File "/opt/stack/nova/nova/compute/manager.py", line 3902, in _finish_resize
    block_device_info, power_on)
  File "/opt/stack/nova/nova/virt/libvirt/driver.py", line 7185, in finish_migration
    self._ensure_console_log_for_instance(instance)
  File "/opt/stack/nova/nova/virt/libvirt/driver.py", line 2845, in _ensure_console_log_for_instance
    libvirt_utils.file_open(console_file, 'a').close()
  File "/opt/stack/nova/nova/virt/libvirt/utils.py", line 313, in file_open
    return open(*args, **kwargs)
IOError: [Errno 13] Permission denied: '/opt/stack/data/nova/instances/ad52ca5b-bb65-4f7c-87e8-750cb3cd9c5e/console.log'

$ ll ~/data/nova/instances/ad52ca5b-bb65-4f7c-87e8-750cb3cd9c5e/
total 24
-rw-rw-r--. 1 qemu qemu 19342 Oct 7 21:23 console.log
-rw-rw-r--. 1 stack libvirtd 2762 Oct 7 21:22 libvirt.xml

Steps to reproduce:
1 Run 2-nodes devstack with Ceph image backend
2 Run an instance
 $ nova boot --image cirros-0.3.4-x86_64-disk --flavor t1.nano inst-1
3 Disable the instance host
 $ nova service-disable 172.16.1.10 nova-compute
4 Resize the instance to another host
 $ nova migrate inst-1
5 Revert resize
 $ nova resize-revert inst-1
6 Resize the instance again
 $ nova migrate inst-1
7 Check the instance state

Actual result - the instance is in error state.
Expected result - the instance is in verify_resize state.

Check n-cpu.log on the second node, where the instance was migrated.

This has been reproduced on master
commit 9c89e07d17b5eb441682e3b8fad8b270f37f7015
Merge: 870a77f 453e71d
Author: Jenkins <email address hidden>
Date: Wed Oct 5 01:35:48 2016 +0000

[Feodor Tersin (ftersin)]

compute manater revert_resize calls driver.destroy on a target host with destroy_disks=False (due to shared block storage flag of Ceph image backend), because that driver.destroy does not instance directory. driver.destroy could delete it with appropriate migrate_data, but no such data exists for revert_resize operation.

[OpenStack Infra (hudson-openstack)]

Related fix proposed to branch: master
Review: https://review.openstack.org/385492

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/385493

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/389593

[OpenStack Infra (hudson-openstack)]

Change abandoned by Feodor Tersin (<email address hidden>) on branch: master
Review: https://review.openstack.org/385493
Reason: in favor of I8d65c904

[OpenStack Infra (hudson-openstack)]

Change abandoned by Feodor Tersin (<email address hidden>) on branch: master
Review: https://review.openstack.org/385492
Reason: in favor of I8d65c904 and its probably descendants (to delete not used migrate_data param)

[OpenStack Infra (hudson-openstack)]

Change abandoned by Michael Still (<email address hidden>) on branch: master
Review: https://review.openstack.org/389593
Reason: This patch has been sitting unchanged for more than 12 weeks. I am therefore going to abandon it to keep the review queue sane. Please feel free to restore the change if you're still working on it.

[OpenStack Infra (hudson-openstack)]

Change abandoned by Stephen Finucane (<email address hidden>) on branch: master
Review: https://review.openstack.org/389593