Support restoreCustomImage for windows with a new interface to extract
the graph driver from the LayerStore.
Signed-off-by: Daniel Nephin <dnephin@docker.com>
RWLayer will now have more operations and be protected through a referenced type rather than always looked up by string in the layer store.
Separates creation of RWLayer (write capture layer) from mounting of the layer.
This allows mount labels to be applied after creation and allowing RWLayer objects to have the same lifespan as a container without performance regressions from requiring mount.
Signed-off-by: Derek McGowan <derek@mcgstyle.net> (github: dmcgowan)
Layer store manages read-only and read-write layers on a union file system.
Read only layers are always referenced by content addresses.
Read-write layer identifiers are handled by the caller but upon registering
its difference, the committed read-only layer will be referenced by content
hash.
Signed-off-by: Derek McGowan <derek@mcgstyle.net> (github: dmcgowan)
Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>