def non_leaf_coalesce(node, parent, uri, cb):
node_vhd = node.vhd
parent_vhd = parent.vhd
log.debug("non_leaf_coalesce key={}, parent={}".format(node_vhd.id, parent_vhd.id))
opq = cb.volumeStartOperations(uri, 'w')
meta_path = cb.volumeMetadataGetPath(opq)
node_path = cb.volumeGetPath(opq, str(node_vhd.id))
log.debug("Running vhd-coalesce on {}".format(node_vhd.id))
VHDUtil.coalesce(GC, node_path)
db = VHDMetabase(meta_path)
with Lock(opq, 'gl', cb):
# reparent all of the children to this node's parent
children = db.get_children(node_vhd.id)
with db.write_context():
journal_entries = db.add_journal_entries(node_vhd.id, parent_vhd.id, children)
__reparent_children(opq, db, cb, journal_entries)
# remove key
log.debug("Destroy {}".format(node_vhd.id))
cb.volumeDestroy(opq, str(node_vhd.id))
with db.write_context():
db.delete_vhd(node_vhd.id)
cb.volumeUnlock(opq, node.lock)
cb.volumeUnlock(opq, parent.lock)
db.close()
cb.volumeStopOperations(opq)
