HK(4) Kernel Interfaces Manual HK(4)
NAME
hk - RK6-11/RK06 and RK07 moving head disk
SYNOPSIS
/sys/conf/SYSTEM:
NHK hk_drives # RK611, RK06/07
/etc/dtab:
#Name Unit# Addr Vector Br Handler(s) # Comments
hk ? 177440 210 5 hkintr # rk611/711 rk06/07
major device number(s):
raw: 13
block: 4
minor device encoding:
bits 0007 specify partition of HK drive
bits 0070 specify HK drive
DESCRIPTION
Files with minor device numbers 0 through 7 refer to various portions of drive 0; minor devices 8 through 15 refer to drive 1, etc. The
standard device names begin with ``hk'' followed by the drive number and then a letter a-h for partitions 0-7 respectively. The character
? stands here for a drive number in the range 0-7.
The block files access the disk via the system's normal buffering mechanism and may be read and written without regard to physical disk
records. There is also a `raw' interface which provides for direct transmission between the disk and the user's read or write buffer. A
single read or write call results in exactly one I/O operation and therefore raw I/O is considerably more efficient when many words are
transmitted. The names of the raw files conventionally begin with an extra `r.'
In raw I/O the buffer must begin on a word (even) boundary, and counts should be a multiple of 512 bytes (a disk sector). Likewise seek
calls should specify a multiple of 512 bytes.
DISK SUPPORT
The origin and size (in sectors) of the pseudo-disks on each drive are as follows:
RK06 partitions:
disk start length cyls comments
hk?a 0 8316 0 - 125 root
hk?b 8316 8316 126 - 251 swap
hk?c 0 27126 0 - 410* whole pack plus badsect track
hk?d unused
hk?e unused
hk?f unused
hk?g 16632 10428 251 - 409 tmp
hk?h 0 27060 0 - 409 whole pack minus badsect track
RK07 partitions:
disk start length cyls comments
hk?a 0 8316 0 - 125 root
hk?b 8316 8316 126 - 251 swap
hk?c 0 53790 0 - 814* whole pack plus badsect track
hk?d unused
hk?e unused
hk?f unused
hk?g 16632 37092 252 - 813
hk?h 0 53724 0 - 814 whole pack minus badsect track
Those partitions marked with an asterisk (``*'') allow access to bad block information stored at the end of some packs. Extreme care must
be taken when creating file systems on these partitions to avoid overwriting any bad block information present. I general it's best to use
newfs(8) to create file systems since it uses the ``safe'' partition sizes recored in /etc/disktab.
FILES
/dev/hk[0-7][a-h] block files
/dev/rhk[0-7][a-h] raw files
/dev/MAKEDEV script to create special files
/dev/MAKEDEV.local script to localize special files
SEE ALSO
ra(4), ram(4), rk(4), rl(4), rx(4), si(4), xp(4), dtab(5), autoconfig(8)
DIAGNOSTICS
hk%d%c: hard error sn%d cs2=%b ds=%b er=%b. An unrecoverable error occurred during transfer of the specified sector of the specified disk
partition. The contents of the cs2, ds and er registers are printed in octal and symbolically with bits decoded. The error was either
unrecoverable, or a large number of retry attempts (including offset positioning and drive recalibration) could not recover the error.
hk%d: write locked. The write protect switch was set on the drive when a write was attempted. The write operation is not recoverable.
hk%d: not ready. The drive was spun down or off line when it was accessed. The i/o operation is not recoverable.
hk%d: not ready (came back!). The drive was not ready, but after printing the message about being not ready (which takes a fraction of a
second) was ready. The operation is recovered if no further errors occur.
hk%d%c: soft ecc sn%d. A recoverable ECC error occurred on the specified sector of the specified disk partition. This happens normally a
few times a week. If it happens more frequently than this the sectors where the errors are occuring should be checked to see if certain
cylinders on the pack, spots on the carriage of the drive or heads are indicated.
BUGS
In raw I/O read and write(2) truncate file offsets to 512-byte block boundaries, and write scribbles on the tail of incomplete blocks.
Thus, in programs that are likely to access raw devices, read, write and lseek(2) should always deal in 512-byte multiples.
DEC-standard error logging should be supported.
A program to analyze the logged error information (even in its present reduced form) is needed.
The partition tables for the file systems should be read off of each pack, as they are never quite what any single installation would pre-
fer, and this would make packs more portable.
3rd Berkeley Distribution January 3, 1993 HK(4)