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diff --git a/share/man/man4/man4.hp300/st.4 b/share/man/man4/man4.hp300/st.4 new file mode 100644 index 00000000000..0d6092cbdd4 --- /dev/null +++ b/share/man/man4/man4.hp300/st.4 @@ -0,0 +1,234 @@ +.\" Copyright (c) 1990, 1991 The Regents of the University of California. +.\" All rights reserved. +.\" +.\" This code is derived from software contributed to Berkeley by +.\" the Systems Programming Group of the University of Utah Computer +.\" Science Department. +.\" +.\" 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. +.\" +.\" from: @(#)st.4 5.3 (Berkeley) 7/31/91 +.\" $Id: st.4,v 1.1 1995/10/18 08:44:28 deraadt Exp $ +.\" +.Dd July 31, 1991 +.Dt ST 4 hp300 +.Os +.Sh NAME +.Nm \&st +.Nd +.Tn CCS SCSI +tape driver +.Sh SYNOPSIS +.Cd "tape st0 at scsi? slave ?" +.Sh DESCRIPTION +The +.Nm \&st +driver was written especially to support the Exabyte +.Tn EXB-8200 8MM +Cartridge +Tape Subsystem. It has several extensions specific to the Exabyte, +but should support other tape drives as long has they follow +the +.Tn ANSI SCSI-I +specification. Besides extensive use with +an Exabyte, the driver has been tested with an +Archive +.Tn QIC-24 +tape drive. +The +.Nm \&st +tape interface provides a standard tape drive interface +as described in +.Xr mtio 4 +with the following exceptions: +.Bl -enum +.It +Density is dependent on device type. Current Exabyte hardware has +only one density. The +.Tn EXB-8500 +drive, when released, will have a high +density format of +.Tn 5.6GB . +On an Archive +.Tn QIC-24 +drive the driver reads both +.Tn QIC-11 +and +.Tn QIC-24 +formats +but writes only +.Tn QIC-24 . +.It +Only the ``raw'' interface is supported. +.El +.Pp +Special Exabyte Support: +.Pp +The +.Dv MTIOCGET +.Xr ioctl 2 +call on an Exabyte returns this structure: +.Bd -literal +struct mtget { + short mt_type; /* type of magtape device */ + short mt_dsreg; /* sc_flags */ + short mt_erreg; /* high 8 bytes error status */ + /* low 8 bytes percentage of Rewrites + if writing, ECC errors if reading */ + short mt_resid; /* Mbyte until end of tape */ +}; +.Ed +.Pp +Bit 4 in the minor device number is used +to select long filemarks or short filemarks. A long filemark occupies +2.12 MBytes of space on the tape, while a short filemark occupies 488 KBytes. +A long filemark includes an erase gap while the short filemark does not. +The tape can be positioned on the +.Tn BOT +side of a long filemark allowing +data to be appended with a write operation. Since the short filemark does not +contain an erase gap which would allow writing it is considered to be +non-erasable. If either type of filemark is followed by blank tape, +data may be appended on its +.Tn EOT +side. +.Pp +Bit 5 in the minor device number selects fixed block mode with a block +size of 1K. Variable length records are the default if bit 5 is not +set. +.Pp +For unit 0 here are the effects of minor device bits 2,3,4,5. For other +units add the +.Em unit# +to each of the device names. +.Bl -column norewind density filemarks -offset indent +.Em norewind high short fixed +.Em density filemarks block mode +rst0 +nrst0 X +rst8 X +nrst8 X X +rst16 X +nrst16 X X +rst24 X X +nrst24 X X X +rst32 X +nrst32 X X +rst40 X X +nrst40 X X X +rst48 X X +nrst48 X X X +rst56 X X X +nrst56 X X X X +.El +.Sh SEE ALSO +.Xr mt 1 , +.Xr tar 1 , +.Xr mtio 4 , +.Rs +.%T EXB-8200 8MM Cartridge Tape Subsystem Interface User Manual. +.Re +.Sh HISTORY +The +.Nm \&st +driver +.Ud +.Sh BUGS +The +.Tn HP +98268 +.Tn SCSI +controller hardware can not do odd length +.Tn DMA +transfers. If odd length +.Tn DMA I/O +is requested the driver will use the +"Program Transfer Mode" of the Fujitsu +.Tn MB87030 +chip. Read requests are +normally even length for which a +.Tn DMA +transfer is used. If, however, the +driver detects that a odd length read has happened (when a even length +was requested) it will issue the +.Dv EIO +error and the last byte of the read +data will be 0x00. Odd length read requests must match the size of the +requested data block on tape. +.Pp +The following only applies when using long filemarks. Short filemarks can +not be overwritten. +.Bd -filled -offset 4n +Due to the helical scan and the erase mechanism, there is a writing +limitation on Exabyte drives. +.Dq Li tar r +or +.Dq Li tar u +will not work +.Pf ( Dq Li tar c +is ok). One can only start writing at 1) beginning of tape, 2) on the +end of what was last written, 3) "front" side of a regular (long) filemark. +Say you have a tape with 3 tar files on it, want to save the first +file, and want to begin writing over the 2nd file. +.Pp +On a normal 1/4" or 1/2" drive you would do: +.Pp +.Li "mt fsf 1; tar cf /dev/nrst0 ..." +.Pp +but for an Exabyte you need to do: +.Pp +.Li "mt fsf 1; mt bsf 1; mt weof 1; tar cf /dev/nrst0 ..." +.Pp +The regular long filemark consists of an erased zone 3.8" long +(needed to begin a write). In this case, the first filemark is +rewritten in place, which creates an erased zone +.Em after +it, clearing the +way to write more on the tape. The erase head is not helical. +.Pp +One can position a tape to the end of what was last written by reading +until a +.Tn \*qBLANK CHECK\*q +error is returned. Writing can be started at this +point. (This applies to both long and short filemarks.) The tape does +not become positioned somewhere down the "erased" area as does a +conventional magtape. One can issue multiple reads at the +.Tn \*qBLANK CHECK\*q +error, but the Exabyte stays positioned at the beginning of the +blank area, ready to accept write commands. File skip operations do +not stop at blank tape and will run into old data or run to the end of +the tape, so you have to be careful not to +.Dq Li mt fsf too_many . +.Ed +.Pp +Archive support gets confused if asked to moved more filemarks than there are +on the tape. +.Pp +This man page needs some work. Some of these are not really bugs, +just unavoidable consequences of the hardware. |