1. devmapper_wrapper_{,no_}deferred_remove.go:
Comments about LibraryDeferredRemovalSupport were very totally
misleading to me. This thing has nothing to do with either static
or dynamic linking (but with build tags). Fix the comment accordingly.
2. devmapper.go:
Reveal the source of those magic device* constants.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Deferred reove functionality was added to library later. So in old version
of library it did not report deferred_remove field.
Create a new function which also gets deferred_remove field and it will be
called only on newer version of library.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
A lot of time device mapper devices leak across mount namespace which docker
does not know about and when docker tries to deactivate/delete device,
operation fails as device is open in some mount namespace.
Create a mechanism where one can defer the device deactivation/deletion
so that docker operation does not fail and device automatically goes
away when last reference to it is dropped.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>