I spent more than a trivial quantity of time figuring out pre_size and
whether a memory region's size contains the header cell or not.
Document the meanings of all the properties. Hopefully now no-one else
has to figure it out!
Signed-off-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
a6c5c52ccf