Comment 7 for bug 1250965

Adding another +1 to wanting swift-storage to allow for directory/mountpoints in swift-storage charm's block-devices as we can use with ceph storage.

Odd, but important use case:

bcache bypass using /dev/loop0 to mount the backing store (8k offset, losetup -o 8192 /dev/loop0 /dev/$bcache_backing_device) and then mounting /dev/loop0 to /srv/node/bcache0 where bcache lived before.