187 lines
6.3 KiB
Groff
187 lines
6.3 KiB
Groff
.\" Copyright (c) 1980, 1988, 1991, 1993
|
|
.\" The Regents of the University of California. All rights reserved.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\" 3. All advertising materials mentioning features or use of this software
|
|
.\" must display the following acknowledgement:
|
|
.\" This product includes software developed by the University of
|
|
.\" California, Berkeley and its contributors.
|
|
.\" 4. Neither the name of the University nor the names of its contributors
|
|
.\" may be used to endorse or promote products derived from this software
|
|
.\" without specific prior written permission.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" @(#)bad144.8 8.1 (Berkeley) 6/6/93
|
|
.\"
|
|
.Dd June 6, 1993
|
|
.Dt BAD144 8
|
|
.Os BSD 4
|
|
.Sh NAME
|
|
.Nm bad144
|
|
.Nd read/write dec standard 144 bad sector information
|
|
.Sh SYNOPSIS
|
|
.Nm bad144
|
|
.Op Fl c
|
|
.Op Fl f
|
|
.Op Fl v
|
|
.Ar disk
|
|
.Oo
|
|
.Ar sno
|
|
.Op Ar bad ...
|
|
.Oc
|
|
.Nm bad144
|
|
.Fl a
|
|
.Op Fl c
|
|
.Op Fl f
|
|
.Op Fl v
|
|
.Ar disk
|
|
.Op Ar bad ...
|
|
.Sh DESCRIPTION
|
|
.Nm Bad144
|
|
can be used to inspect the information stored on a disk that is used by
|
|
the disk drivers to implement bad sector forwarding.
|
|
.Pp
|
|
Available options:
|
|
.Pp
|
|
.Bl -tag -width Ds
|
|
.It Fl a
|
|
The argument list consists of new bad sectors to be added to an existing
|
|
list.
|
|
The new sectors are sorted into the list,
|
|
which must have been in order.
|
|
Replacement sectors are moved to accommodate the additions;
|
|
the new replacement sectors are cleared.
|
|
.It Fl c
|
|
Forces an attempt to copy the old sector to the replacement,
|
|
and may be useful when replacing an unreliable sector.
|
|
.It Fl f
|
|
For a RP06, RM03, RM05, Fujitsu Eagle,
|
|
or
|
|
.Tn SMD
|
|
disk on a Massbus, the
|
|
.Fl f
|
|
option may be used to mark the new bad sectors as ``bad''
|
|
by reformatting them as unusable sectors.
|
|
This option is
|
|
.Em required unless
|
|
the sectors have already been marked bad,
|
|
or the system will not be notified that it should use the replacement sector.
|
|
This option may be used while running multiuser; it is no longer necessary
|
|
to perform format operations while running single-user.
|
|
.It Fl v
|
|
The entire process is described as it happens in gory detail if
|
|
.Fl v
|
|
(verbose) is given.
|
|
.El
|
|
.Pp
|
|
The format of
|
|
the information is specified by
|
|
.Tn DEC
|
|
standard 144, as follows.
|
|
The bad sector information is located in the first 5 even numbered sectors
|
|
of the last track of the disk pack. There are five identical copies of
|
|
the information, described by the
|
|
.Ar dkbad
|
|
structure.
|
|
.Pp
|
|
Replacement sectors are allocated starting with the first sector before
|
|
the bad sector information and working backwards towards the beginning
|
|
of the disk. A maximum of 126 bad sectors are supported. The position
|
|
of the bad sector in the bad sector table determines the replacement
|
|
sector to which it corresponds.
|
|
The bad sectors must be listed in ascending order.
|
|
.Pp
|
|
The bad sector information and replacement sectors are conventionally
|
|
only accessible through the ``c'' file system partition of the disk. If
|
|
that partition is used for a file system, the user is responsible for
|
|
making sure that it does not overlap the bad sector information or any
|
|
replacement sectors.
|
|
Thus, one track plus 126 sectors must be reserved to allow use
|
|
of all of the possible bad sector replacements.
|
|
.Pp
|
|
The bad sector structure is as follows:
|
|
.Bd -literal
|
|
struct dkbad {
|
|
long bt_csn; /* cartridge serial number */
|
|
u_short bt_mbz; /* unused; should be 0 */
|
|
u_short bt_flag; /* -1 => alignment cartridge */
|
|
struct bt_bad {
|
|
u_short bt_cyl; /* bad sector cylinder number */
|
|
u_short bt_trksec; /* track and sector number */
|
|
} bt_bad[126];
|
|
};
|
|
.Ed
|
|
.Pp
|
|
Unused slots in the
|
|
.Ar bt_bad
|
|
array are filled with all bits set, a putatively
|
|
illegal value.
|
|
.Pp
|
|
.Nm Bad144
|
|
is invoked by giving a device name (e.g. hk0, hp1, etc.).
|
|
With no optional arguments
|
|
it reads the first sector of the last track
|
|
of the corresponding disk and prints out the bad sector information.
|
|
It issues a warning if the bad sectors are out of order.
|
|
.Nm Bad144
|
|
may also be invoked with a serial number for the pack and a list
|
|
of bad sectors.
|
|
It will write the supplied information into all copies
|
|
of the bad-sector file, replacing any previous information.
|
|
Note, however, that
|
|
.Nm bad144
|
|
does not arrange for the specified sectors to be marked bad in this case.
|
|
This procedure should only be used to restore known bad sector information which
|
|
was destroyed.
|
|
.Pp
|
|
It is no longer necessary to reboot to allow the kernel
|
|
to reread the bad-sector table from the drive.
|
|
.Sh SEE ALSO
|
|
.Xr badsect 8 ,
|
|
.Xr format 8
|
|
.Sh BUGS
|
|
It should be possible to format disks on-line under
|
|
.Tn UNIX .
|
|
.Pp
|
|
It should be possible to mark bad sectors on drives of all type.
|
|
.Pp
|
|
On an 11/750,
|
|
the standard bootstrap drivers used to boot the system do
|
|
not understand bad sectors,
|
|
handle
|
|
.Tn ECC
|
|
errors, or the special
|
|
.Tn SSE
|
|
(skip sector) errors of RM80-type disks.
|
|
This means that none of these errors can occur when reading the file
|
|
.Pa /vmunix
|
|
to boot. Sectors 0-15 of the disk drive
|
|
must also not have any of these errors.
|
|
.Pp
|
|
The drivers which write a system core image on disk after a crash do not
|
|
handle errors; thus the crash dump area must be free of errors and bad
|
|
sectors.
|
|
.Sh HISTORY
|
|
The
|
|
.Nm
|
|
command appeared in
|
|
.Bx 4.1 .
|