NAME
hp
-
MASSBUS
disk interface
SYNOPSIS
hp0 at mba0 drive 0
hp* at mba? drive ?
DESCRIPTION
The
hp
driver
is a generic MASSBUS disk driver which handles the standard
DEC
controllers.
It is typical of a block-device disk driver; block
I/O
is
described in
physio(4).
The script
MAKEDEV(8)
should be used to create the special files; if a special file
needs to be created by hand consult
mknod(8).
It is recommended as a security precaution to not create special files
for devices which may never be installed.
The first sector of each disk contains both a first-stage bootstrap program
and a disk label containing geometry information and partition layouts (see
disklabel(5).
This sector is normally write-protected, and disk-to-disk copies should
avoid copying this sector.
The label may be updated with
disklabel(8),
which can also be used to write-enable and write-disable the sector.
The next 15 sectors contain a second-stage bootstrap program.
DISK SUPPORT
During autoconfiguration or whenever a drive comes on line for the first time,
or when a drive is opened after all partitions are closed,
the first sector of the drive is examined for a disk label.
If a label is found, the geometry of the drive and the partition tables
are taken from it.
If no label is found, a fake label is created by the driver, enough
so that a real label can be written.
The hp?a partition is normally used for the root file system,
the hp?b partition as a paging area,
and the hp?c partition for pack-pack copying (it maps the entire disk).
On disks larger than about 205 Megabytes, the hp?h partition
is inserted prior to the hp?d or hp?g partition;
the hp?g partition then maps the remainder of the pack.
FILES
/dev/hp[0-7][a-h]
-
block files
/dev/rhp[0-7][a-h]
-
raw files
DIAGNOSTICS
- hp%d%c: hard error %sing fsbn %d [of %d-%d] (hp%d bn %d cn %d tn %d sn %d) mbsr=%b er1=%b er2=%b.
-
An unrecoverable error occurred during transfer of the specified
filesystem block number,
which is a logical block number on the indicated partition.
If the transfer involved multiple blocks, the block range is printed as well.
The parenthesized fields list the actual disk sector number
relative to the beginning of the drive,
as well as the cylinder, track and sector number of the block.
The
MASSBUS
status register is printed in hexadecimal and
with the error bits decoded if any error bits other than
MBEXC
and
DTABT
are set. In any case the contents of the two error registers are also printed
in octal and symbolically with bits decoded.
(Note that er2 is what old
RP06
manuals would call
RPER3;
the terminology
is that of the
RM
disks).
The error was either unrecoverable, or a large number of retry attempts
(including offset positioning and drive recalibration) could not
recover the error.
- hp%d%c: soft ecc reading fsbn %d [of %d-%d] (hp%d bn %d cn %d tn %d sn %d).
-
A recoverable
ECC
error occurred on the
specified sector of the specified disk partition.
If the transfer involved multiple blocks, the block range is printed as well.
The parenthesized fields list the actual disk sector number
relative to the beginning of the drive,
as well as the cylinder, track and sector number of the block.
This happens normally
a few times a week. If it happens more frequently than
this the sectors where the errors are occurring should be checked to see
if certain cylinders on the pack, spots on the carriage of the drive
or heads are indicated.
SEE ALSO
physio(4),
up(4),
disklabel(5),
MAKEDEV(8),
disklabel(8),
mknod(8)
HISTORY
The
hp
driver appeared in
4.0BSD.
A new
hp
driver showed up in
NetBSD1.2.
BUGS
DEC-standard
bad144(8)
bad-block handling should be used.
DEC-standard
error logging should be supported.
A program to analyze the logged error information (even in its
present reduced form) is needed.