This function is for internal use only.
Both maps must exist.
The range must have been created with
No other operations may have been performed on this range
before calling this function.
operation may be performed within this range after calling
To remove a submapping, one must first remove the range from
and then destroy the
This procedure is not recommended.
Otherwise, it returns
if the caller requested copy-on-write flags,
or if the range specified for the sub-map was out of range for the parent map,
or if a
backing object was specified.