Comment 2 for bug 1888680

I just attempted to reproduce this and it's even more broken than I originally thought.

While we hit c#0 when creating the image based encrypted NFS volume we then also see os-brick overwriting the entire original file with a symlink to the decrypted dm-crypt device:

$ openstack volume type create --encryption-provider nova.volume.encryptors.luks.LuksEncryptor --encryption-cipher aes-xts-plain64 --encryption-key-size 256 --encryption-control-location front-end LUKS
$ openstack volume create --image cirros-0.5.1-x86_64-disk --type LUKS --size 1 test-encrypted-image
[..]
| id | 9b3a4f89-4194-4972-9292-b60c97c824e2 |
[..]

$ ll /opt/stack/data/cinder/mnt/896fb15da6036b68a917322e72ebfe57/volume-*
lrwxrwxrwx. 1 root root 61 Aug 21 08:24
/opt/stack/data/cinder/mnt/896fb15da6036b68a917322e72ebfe57/volume-9b3a4f89-4194-4972-9292-b60c97c824e2
-> /dev/mapper/crypt-volume-9b3a4f89-4194-4972-9292-b60c97c824e2

^ removing the original encrypted file entirely, so before fixing c#0 we also need to resolve this.