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DK(4)                        Device Drivers Manual                       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.

NetBSD 11.99                     April 2, 2024                    NetBSD 11.99