uda.4

早期freebsd实现

.\" Copyright (c) 1980, 1987, 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.
.\"
.\"     @(#)uda.4	8.1 (Berkeley) 6/5/93
.\"
.Dd June 5, 1993
.Dt UDA 4 vax
.Os BSD 4
.Sh NAME
.Nm uda
.Nd
.Tn UDA50
disk controller interface
.Sh SYNOPSIS
.Cd "controller uda0 at uba0 csr 0172150 vector udaintr"
.Cd "disk ra0 at uda0 drive 0"
.Cd "options MSCP_PARANOIA"
.Sh DESCRIPTION
This is a driver for the
.Tn DEC UDA50
disk controller and other
compatible controllers.  The
.Tn UDA50
communicates with the host through
a packet protocol known as the Mass Storage Control Protocol
.Pq Tn MSCP .
Consult the file
.Aq Pa vax/mscp.h
for a detailed description of this protocol.
.Pp
The
.Nm uda
driver
is a typical block-device disk driver; see
.Xr physio 4
for a description of block
.Tn I/O .
The script
.Xr MAKEDEV 8
should be used to create the
.Nm uda
special files; should a special
file need to be created by hand, consult
.Xr mknod 8 .
.Pp
The
.Dv MSCP_PARANOIA
option enables runtime checking on all transfer completion responses
from the controller.  This increases disk
.Tn I/O
overhead and may
be undesirable on slow machines, but is otherwise recommended.
.Pp
The first sector of each disk contains both a first-stage bootstrap program
and a disk label containing geometry information and partition layouts (see
.Xr disklabel 5 ) .
This sector is normally write-protected, and disk-to-disk copies should
avoid copying this sector.
The label may be updated with
.Xr 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.
.Sh DISK SUPPORT
During autoconfiguration,
as well as 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,
the driver configures the type of each drive when it is first
encountered.  A default partition table in the driver is used for each type
of disk when a pack is not labelled.  The origin and size
(in sectors) of the default pseudo-disks on each
drive are shown below.  Not all partitions begin on cylinder
boundaries, as on other drives, because previous drivers used one
partition table for all drive types.  Variants of the partition tables
are common; check the driver and the file
.Pa /etc/disktab
.Pq Xr disktab 5
for other possibilities.
.Pp
Special file names begin with
.Sq Li ra
and
.Sq Li rra
for the block and character files respectively. The second
component of the name, a drive unit number in the range of zero to
seven, is represented by a
.Sq Li ?
in the disk layouts below. The last component of the name is the
file system partition
designated
by a letter from
.Sq Li a
to
.Sq Li h
and which corresponds to a minor device number set: zero to seven,
eight to 15, 16 to 23 and so forth for drive zero, drive two and drive
three respectively, (see
.Xr physio 4) .
The location and size (in sectors) of the partitions:
.Bl -column header diskx undefined length
.Tn RA60 No partitions
.Sy	disk	start	length
	ra?a	0	15884
	ra?b	15884	33440
	ra?c	0	400176
	ra?d	49324	82080	same as 4.2BSD ra?g
	ra?e	131404	268772	same as 4.2BSD ra?h
	ra?f	49324	350852
	ra?g	242606	157570
	ra?h	49324	193282

.Tn RA70 No partitions
.Sy	disk	start	length
	ra?a	0	15884
	ra?b	15972	33440
	ra?c	0	547041
	ra?d	34122	15884
	ra?e	357192	55936
	ra?f	413457	133584
	ra?g	341220	205821
	ra?h	49731	29136

.Tn RA80 No partitions
.Sy	disk	start	length
	ra?a	0	15884
	ra?b	15884	33440
	ra?c	0	242606
	ra?e	49324	193282	same as old Berkeley ra?g
	ra?f	49324	82080	same as 4.2BSD ra?g
	ra?g	49910	192696
	ra?h	131404	111202	same as 4.2BSD

.Tn RA81 No partitions
.Sy	disk	start	length
	ra?a	0	15884
	ra?b	16422	66880
	ra?c	0	891072
	ra?d	375564	15884
	ra?e	391986	307200
	ra?f	699720	191352
	ra?g	375564	515508
	ra?h	83538	291346

.Tn RA81 No partitions with 4.2BSD-compatible partitions
.Sy	disk	start	length
	ra?a	0	15884
	ra?b	16422	66880
	ra?c	0	891072
	ra?d	49324	82080	same as 4.2BSD ra?g
	ra?e	131404	759668	same as 4.2BSD ra?h
	ra?f	412490	478582	same as 4.2BSD ra?f
	ra?g	375564	515508
	ra?h	83538	291346

.Tn RA82 No partitions
.Sy	disk	start	length
	ra?a	0	15884
	ra?b	16245	66880
	ra?c	0	1135554
	ra?d	375345	15884
	ra?e	391590	307200
	ra?f	669390	466164
	ra?g	375345	760209
	ra?h	83790	291346
.El
.Pp
The ra?a partition is normally used for the root file system, the ra?b
partition as a paging area, and the ra?c partition for pack-pack
copying (it maps the entire disk).
.Sh FILES
.Bl -tag -width /dev/rra[0-9][a-f] -compact
.It Pa /dev/ra[0-9][a-f]
.It Pa /dev/rra[0-9][a-f]
.El
.Sh DIAGNOSTICS
.Bl -diag
.It "panic: udaslave"
No command packets were available while the driver was looking
for disk drives.  The controller is not extending enough credits
to use the drives.
.Pp
.It "uda%d: no response to Get Unit Status request"
A disk drive was found, but did not respond to a status request.
This is either a hardware problem or someone pulling unit number
plugs very fast.
.Pp
.It "uda%d: unit %d off line"
While searching for drives, the controller found one that
seems to be manually disabled.  It is ignored.
.Pp
.It "uda%d: unable to get unit status"
Something went wrong while trying to determine the status of
a disk drive.  This is followed by an error detail.
.Pp
.It uda%d: unit %d, next %d
This probably never happens, but I wanted to know if it did.  I
have no idea what one should do about it.
.Pp
.It "uda%d: cannot handle unit number %d (max is %d)"
The controller found a drive whose unit number is too large.
Valid unit numbers are those in the range [0..7].
.Pp
.It "ra%d: don't have a partition table for %s; using (s,t,c)=(%d,%d,%d)"
The controller found a drive whose media identifier (e.g. `RA 25')
does not have a default partition table.  A temporary partition
table containing only an `a' partition has been created covering
the entire disk, which has the indicated numbers of sectors per
track (s), tracks per cylinder (t), and total cylinders (c).
Give the pack a label with the
.Xr disklabel
utility.
.Pp
.It "uda%d: uballoc map failed"
Unibus resource map allocation failed during initialisation.  This
can only happen if you have 496 devices on a Unibus.
.Pp
.It uda%d: timeout during init
The controller did not initialise within ten seconds.  A hardware
problem, but it sometimes goes away if you try again.
.Pp
.It uda%d: init failed, sa=%b
The controller refused to initalise.
.Pp
.It uda%d: controller hung
The controller never finished initialisation.  Retrying may sometimes
fix it.
.Pp
.It ra%d: drive will not come on line
The drive will not come on line, probably because it is spun down.
This should be preceded by a message giving details as to why the
drive stayed off line.
.Pp
.It uda%d: still hung
When the controller hangs, the driver occasionally tries to reinitialise
it.  This means it just tried, without success.
.Pp
.It panic: udastart: bp==NULL
A bug in the driver has put an empty drive queue on a controller queue.
.Pp
.It uda%d: command ring too small
If you increase
.Dv NCMDL2 ,
you may see a performance improvement.
(See
.Pa /sys/vaxuba/uda.c . )
.Pp
.It panic: udastart
A drive was found marked for status or on-line functions while performing
status or on-line functions.  This indicates a bug in the driver.
.Pp
.It "uda%d: controller error, sa=0%o (%s)"
The controller reported an error.  The error code is printed in
octal, along with a short description if the code is known (see the
.%T UDA50 Maintenance Guide ,
.Tn DEC
part number
.Tn AA-M185B-TC ,
pp. 18-22).
If this occurs during normal
operation, the driver will reset it and retry pending
.Tn I/O .
If
it occurs during configuration, the controller may be ignored.
.Pp
.It uda%d: stray intr
The controller interrupted when it should have stayed quiet.  The
interrupt has been ignored.
.Pp
.It "uda%d: init step %d failed, sa=%b"
The controller reported an error during the named initialisation step.
The driver will retry initialisation later.
.Pp
.It uda%d: version %d model %d
An informational message giving the revision level of the controller.
.Pp
.It uda%d: DMA burst size set to %d
An informational message showing the
.Tn DMA