David Woodhouse originally contributed this code, and Chris Mason
changed it around to reflect the current design goals for raid56.
The original code expected all metadata and data writes to be full
stripes. This meant metadata block size == stripe size, and had a few
other restrictions.
This version allows metadata blocks smaller than the stripe size. It
implements both raid5 and raid6, although it does not have code to
rebuild from parity if one of the drives is missing or incorrect.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
This is mostly disabled, but it is step one in handling
corrupted block groups in the extent allocation tree.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
When we discover bad blocks in the extent allocation tree, repair can
now discard them and recreate the references from the rest of the trees.
Signed-off-by: Chris Mason <chris.mason@oracle.com>