DK(4)

NAME
dk - disk partition (wedge) driver

SYNOPSIS
options DKWEDGE_AUTODISCOVER
options DKWEDGE_METHOD_APPLE
options DKWEDGE_METHOD_BSDLABEL
options DKWEDGE_METHOD_GPT
options DKWEDGE_METHOD_MBR
options DKWEDGE_METHOD_RDB
options DKWEDGE_METHOD_TOS

DESCRIPTION
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.

KERNEL OPTIONS

DKWEDGE_AUTODISCOVER
    Automatically detect and configure wedges using any available methods. For each partition found, a wedge with a corresponding name is created.

    Currently only DKWEDGE_METHOD_GPT and DKWEDGE_METHOD_APPLE are enabled by default.

DKWEDGE_METHOD_APPLE
    Apple partition map detection method.

DKWEDGE_METHOD_BSDLABEL
    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’.

DKWEDGE_METHOD_GPT
    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.

DKWEDGE_METHOD_MBR
    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’.

DKWEDGE_METHOD_RDB
    Amiga Rigid Disk Block (RDB) partitioning detection method.

DKWEDGE_METHOD_TOS
    Atari's TOS partition map detection method, for disks that conform to Atari's AHDI specification.

    For each partition, a wedge is created with a name of the format ATARI_{type}_{number} where type may either be ‘GEM’ or ‘BGM’. The number 0 partition typically corresponds to the ‘C:’ drive when read on an actual Atari, the next to ‘D:’ and so on. Extended partitions (those of type ‘XGM’) are not currently supported.

FILES
/dev/dk*
    Block mode dk device special files.
/dev/rdk*
    Raw mode dk device special files.

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

HISTORY
The dk driver first appeared in NetBSD 3.0.

AUTHORS
The dk driver was written by Jason R. Thorpe.