CMDK(4D) CMDK(4D)


NAME


cmdk - common disk driver

SYNOPSIS


cmdk@target, lun : [ partition | slice ]


DESCRIPTION


The cmdk device driver is a common interface to various disk devices. The
driver supports magnetic fixed disks and magnetic removable disks.


The cmdk device driver supports three different disk labels: fdisk
partition table, Solaris x86 VTOC and EFI/GPT.


The block-files access the disk using the system's normal buffering
mechanism and are read and written without regard to physical disk
records. There is also a "raw" interface that provides for direct
transmission between the disk and the user's read or write buffer. A
single read or write call usually results in one I/O operation; raw I/O
is therefore considerably more efficient when many bytes are transmitted.
The names of the block files are found in /dev/dsk. Raw file names are
found in /dev/rdsk.


I/O requests to the magnetic disk must have an offset and transfer length
that is a multiple of 512 bytes or the driver returns an EINVAL error.


Slice 0 is normally used for the root file system on a disk, slice 1 as a
paging area (for example, swap), and slice 2 for backing up the entire
fdisk partition for Solaris software. Other slices may be used for usr
file systems or system reserved area.


The fdisk partition 0 is to access the entire disk and is generally used
by the fdisk(8) program.

FILES


/dev/dsk/cndn[s|p]n
block device (IDE)


/dev/rdsk/cndn[s|p]n
raw device (IDE)

where:

cn
controller n.


dn
lun n (0-1).


sn
UNIX system slice n (0-15).


pn
fdisk partition (0-36).


/kernel/drv/cmdk
32-bit kernel module.


/kernel/drv/amd64/cmdk
64-bit kernel module.


ATTRIBUTES


See attributes(7) for descriptions of the following attributes:


+---------------+-----------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+-----------------+
|Architecture | x86 |
+---------------+-----------------+

SEE ALSO


lseek(2), read(2), write(2), readdir(3C), dkio(4I), scsi(5), vfstab(5),
attributes(7), fdisk(8), mount(8)


November 4, 2008 CMDK(4D)