DK(4) Device Drivers Manual DK(4)

dk
disk partition (wedge) driver

options DKWEDGE_AUTODISCOVER
options DKWEDGE_METHOD_BSDLABEL
options DKWEDGE_METHOD_GPT
options DKWEDGE_METHOD_MBR
options DKWEDGE_METHOD_RDB
options DKWEDGE_METHOD_APPLE

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.

Wedges need to have unique names. If a duplicate name is detected during auto-discovery, that partition is ignored.

Automatically detect and configure wedges using any available methods.

Currently only DKWEDGE_METHOD_GPT and DKWEDGE_METHOD_APPLE are enabled by default.

For each partition found, a wedge with a corresponding name is created.

BSD disklabel detection method. For each configured partition in the disklabel(5) that is not of type FS_UNUSED, a wedge is created and named after the d_packname field followed by ‘/’ and the partition letter ‘a’..‘p’.

When the d_packname is empty or has the value “fictitious”, the regular partition names are used as wedge names, i.e. the device name, unit number and partition letter, for example “wd0a”.

Extensible Firmware Interface Globally Unique Identifier Partition Table (GPT) detection method.

For every GPT partition a wedge is created and named after the partition label. GPT partitions are UTF-16-encoded, this is converted into UTF-8. If a partition has no label, its UUID is used instead.

IBM PC-compatible Master Boot Record (MBR) partitioning detection method, with support for Extended MBRs.

For every partition in the MBR a wedge is created and named like a regular partition name, i.e. the device name, unit number and a partition letter, for example “wd0e”. Primary partitions start with ‘e’, extended partitions start with ‘i’.

Amiga Rigid Disk Block (RDB) partitioning detection method.
Apple partition map detection method.

/dev/{,r}dk*
dk device special files.

config(1), disklabel(8), dkctl(8), fdisk(8), gpt(8), MAKEDEV(8)

The dk driver first appeared in NetBSD 3.0.

The dk driver was written by Jason R. Thorpe.
January 6, 2021 NetBSD 10.0