Clean up the shared storage check (#891756)

The shared storage check for live and block migration is currently
very confusing e.g.

  * The mounted_on_same_shared_storage() method raises FileNotFound
    for the caller to catch rather than just returning a boolean to
    indicate whether the hosts share storage

  * mounted_on_same_shared_storage() has a "filename is not None" check
    in its finally clause which doesn't make sense

  * InvalidSharedStorage is not raised in the live migration case,

  * instead
    FileNotFound is raised

Clean all this up by having mounted_on_same_shared_storage() simply
return a boolean and have simple logic to raise InvalidSharedStorage for live
migration where no shared storage is available or for block migration where
shared storage is available.

Change-Id: I96f354fe41d9ce77c4cc98903f0d5a9de99ac4f6

0 files changed, 0 insertions, 0 deletions