Scrub should make sure that each bnobt record has a corresponding
cntbt record.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

When we're scrubbing various btrees, cross-reference the records with
the bnobt to ensure that we don't also think the space is free.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

Create some stubs that will be used to cross-reference metadata records.
The actual cross-referencing will be filled in by subsequent patches.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

Check the extent records free space btrees to ensure that the values
look sane.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>