Add expect_deleted flag in volume db

Registered by Rongze Zhu

Adding expect_deleted flag in volume db to address 'delete volume issue'.
When we want to delete a volume, we can set expect_deleted=True and call db.volume_destroy, So billing and metering are stoped. We can add new periodic task to check the expect_deleted flag of the volume, and the periodic task will use dd to write zero to volume.

Blueprint information

Status:
Complete
Approver:
None
Priority:
Low
Drafter:
None
Direction:
Needs approval
Assignee:
Rongze Zhu
Definition:
Obsolete
Series goal:
None
Implementation:
Not started
Milestone target:
None
Completed by
Sean McGinnis

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Sprints

Whiteboard

Some backends take care of their own zeroing, so it should be optional...

(?)

Work Items

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