dk —
disk partition (wedge) driver
options DKWEDGE_AUTODISCOVER
options DKWEDGE_METHOD_BSDLABEL
options DKWEDGE_METHOD_GPT
options DKWEDGE_METHOD_MBR
options DKWEDGE_METHOD_RDB
The dk driver provides a disk-like interface, or
  wedge, to an area of a physical disk. Wedges may be
  configured manually with dkctl(8)
  or automatically by the kernel upon the attachment of the physical disk.
  - /dev/{,r}dk*
- dkdevice special files.
Thedk driver first appeared in NetBSD
  3.0.
The dk driver was written by Jason R.
  Thorpe.