defined by the SNIA Common RAID Disk Data Format Specification v2.0.
Supports multiple volumes per array and multiple partitions per disk.
Supports standard big-endian and Adaptec's little-endian byte ordering.
Supports all single-layer RAID levels. Dual-layer RAID levels except
RAID10 are not supported now because of GEOM RAID design limitations.
Some work is still to be done, but the present code already manages basic
interoperation with RAID BIOS of the Adaptec 1430SA SATA RAID controller.
MFC after: 1 month
Sponsored by: iXsystems, Inc.
