This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
from:
Sergey Ryzhkov, Serge Vakulenko
E-mail: <sir@kiae.su>, <vak@zebub.msk.su>
This is the streamer tape driver for 386bsd and FreeBSD, which
supports Wangtek and Archive compatible QIC-02/QIC-36 controllers.
It was developed as a replacement of the old Wangtek tape driver from CMU.
In comparison with the CMU driver, this version has the following enhancements:
1) Support for Archive SC402 and SC499 tape controllers added.
2) Support for up to three tape controllers on the same machine.
3) Support for BSD-style ioctls MTIOCGET, MTIOCTOP.
Mt command now works adequately with this driver.
2) Asynchronous REWIND and FSF operations, close() will not wait
until they finish. The next open() will wait for it instead.
4) Use of WTQICMD ioctl is limited to ERASE and RETENS operations.
This prevents the user from locking the tape driver by strange
tape operations.
5) Tape density switching added.
6) The status of the process, blocked on the tape operation,
is displayed at the WCHAN column of the `ps' command as:
wtread reading data from the tape
wtwrite writing data to the tape
wtrfm reading the tape marker
wtwfm writing the tape marker
wtrew rewinding the tape
wterase doing WTQICMD ERASE operation
wtretens doing WTQICMD RETENS operation
wtorew doing MTIOCTOP REW/OFFL operation
wtorfm doing MTIOCTOP FSF operation
wtowfm doing MTIOCTOP WEOF operation
7) It's possible to use the tape with "default density",
useful for devices which don't support density switching
or do automatic format determination.
8) Some controllers support only 1024 block length.
Setting WT_BSIZE bit in device minor number turns on this mode.
Minor number structure:
0bfffuuu
Fields:
uuu - Unit number. It's possible to install
up to three tape controllers on the same machine,
using DRQs 1..3. Hence, unit number can lie
in range 0..2.
fff - Tape format number:
0 - /dev/rwt0 - default density (auto select)
1 - /dev/rwt0a - QIC 11 (obsolete)
2 - /dev/rwt0b - QIC 24 (60 megabytes)
3 - /dev/rwt0c - QIC 120 (120 megabytes)
4 - /dev/rwt0d - QIC 150 (150 megabytes)
5 - /dev/rwt0e - QIC 300 (300 megabytes?)
6 - /dev/rwt0f - QIC 600 (600 megabytes?)
b - Long block size flag. With this bit set,
the driver will perform all i/o operations
with the controller using 1024-byte
blocks, instead of 512 ones.
Some controllers need it (CMS for example).
If you Wangtek controller does not stream well,
you can try to use /dev/rWt0 device instead
of /dev/rwt0 (uncomment needed lines in /dev/MAKEDEV
to create it).
Block interface (writing blocks less than 2048 bytes) is not functioning
pwoperly. Use raw interface instead.
Thanks to all who helped to test it on the following hardware:
Controller Drive Volume Interface Thanks to
---------------------------------------------------------------------------
Archive SC-499 Archive 2150L 150 Meg QIC-02 KIAE
CMS? ? 150 Meg QIC-02 KIAE
Everex EV 831/833 ? ? QIC-36 Joergen Haegg
Wangtek ASSY Wangtek 60 Meg QIC-02 Ken Whedbee
Tecmar QT150i? Wangtek 5150EQ ? QIC-02? Marko Teiste
? Wangtek 5099EK 60 Meg QIC-36 Robert Shien
Archive SC400S ? 60 Meg ? Warren Toomey
Date: Thu, 30 Sep 1993 15:13:17 +0300
Description:
Old wt driver is too incomplete and buggy.
It does not support Archive controllers, BSD-like
tape ioctls, multiple tape controllers, different
tape density etc.
Fix:
This driver is a replacement of the old one.
It was not tested on different controllers, though.
This is the streamer tape driver for 386bsd and FreeBSD,
which supports Wangtek and Archive controllers.
It was developed as a replacement of the old Wangtek
tape driver from CMU.
In comparison with the CMU driver, this version has the following enhancements:
1) Support for Archive SC402 and SC499 tape controllers added.
2) Support for up to three tape controllers on the same machine.
3) Support for BSD-style ioctls MTIOCGET, MTIOCTOP.
Mt command now works adequately with this driver.
4) Asynchronous REWIND and FSF operations, close() will not wait
until they finish. The next open() will wait for it instead.
5) Use of WTQICMD ioctl is limited to ERASE and RETENS operations.
This prevents the user from locking the tape driver by strange
tape operations.
6) Tape density switching added.
7) The status of the process, blocked on the tape operation,
is displayed at the WCHAN column of the `ps' command as:
wtread reading data from the tape
wtwrite writing data to the tape
wtrfm reading the tape marker
wtwfm writing the tape marker
wtrew rewinding the tape
wterase doing WTQICMD ERASE operation
wtretens doing WTQICMD RETENS operation
wtorew doing MTIOCTOP REW/OFFL operation
wtorfm doing MTIOCTOP FSF operation
wtowfm doing MTIOCTOP WEOF operation
Block interface (writing blocks less than 2048 bytes) is not functioning
pwoperly. Use raw interface instead.
