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@@ -1,122 +0,0 @@
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-Channel attached Tape device driver
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-
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------------------------------WARNING-----------------------------------------
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-This driver is considered to be EXPERIMENTAL. Do NOT use it in
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-production environments. Feel free to test it and report problems back to us.
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------------------------------------------------------------------------------
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-
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-The LINUX for zSeries tape device driver manages channel attached tape drives
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-which are compatible to IBM 3480 or IBM 3490 magnetic tape subsystems. This
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-includes various models of these devices (for example the 3490E).
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-
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-
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-Tape driver features
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-
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-The device driver supports a maximum of 128 tape devices.
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-No official LINUX device major number is assigned to the zSeries tape device
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-driver. It allocates major numbers dynamically and reports them on system
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-startup.
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-Typically it will get major number 254 for both the character device front-end
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-and the block device front-end.
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-
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-The tape device driver needs no kernel parameters. All supported devices
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-present are detected on driver initialization at system startup or module load.
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-The devices detected are ordered by their subchannel numbers. The device with
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-the lowest subchannel number becomes device 0, the next one will be device 1
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-and so on.
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-
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-
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-Tape character device front-end
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-
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-The usual way to read or write to the tape device is through the character
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-device front-end. The zSeries tape device driver provides two character devices
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-for each physical device -- the first of these will rewind automatically when
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-it is closed, the second will not rewind automatically.
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-
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-The character device nodes are named /dev/rtibm0 (rewinding) and /dev/ntibm0
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-(non-rewinding) for the first device, /dev/rtibm1 and /dev/ntibm1 for the
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-second, and so on.
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-
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-The character device front-end can be used as any other LINUX tape device. You
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-can write to it and read from it using LINUX facilities such as GNU tar. The
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-tool mt can be used to perform control operations, such as rewinding the tape
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-or skipping a file.
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-
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-Most LINUX tape software should work with either tape character device.
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-
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-
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-Tape block device front-end
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-
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-The tape device may also be accessed as a block device in read-only mode.
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-This could be used for software installation in the same way as it is used with
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-other operation systems on the zSeries platform (and most LINUX
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-distributions are shipped on compact disk using ISO9660 filesystems).
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-
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-One block device node is provided for each physical device. These are named
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-/dev/btibm0 for the first device, /dev/btibm1 for the second and so on.
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-You should only use the ISO9660 filesystem on LINUX for zSeries tapes because
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-the physical tape devices cannot perform fast seeks and the ISO9660 system is
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-optimized for this situation.
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-
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-
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-Tape block device example
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-
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-In this example a tape with an ISO9660 filesystem is created using the first
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-tape device. ISO9660 filesystem support must be built into your system kernel
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-for this.
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-The mt command is used to issue tape commands and the mkisofs command to
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-create an ISO9660 filesystem:
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-
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-- create a LINUX directory (somedir) with the contents of the filesystem
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- mkdir somedir
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- cp contents somedir
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-
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-- insert a tape
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-
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-- ensure the tape is at the beginning
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- mt -f /dev/ntibm0 rewind
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-
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-- set the blocksize of the character driver. The blocksize 2048 bytes
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- is commonly used on ISO9660 CD-Roms
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- mt -f /dev/ntibm0 setblk 2048
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-
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-- write the filesystem to the character device driver
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- mkisofs -o /dev/ntibm0 somedir
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-
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-- rewind the tape again
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- mt -f /dev/ntibm0 rewind
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-
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-- Now you can mount your new filesystem as a block device:
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- mount -t iso9660 -o ro,block=2048 /dev/btibm0 /mnt
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-
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-TODO List
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-
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- - Driver has to be stabilized still
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-
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-BUGS
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-
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-This driver is considered BETA, which means some weaknesses may still
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-be in it.
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-If an error occurs which cannot be handled by the code you will get a
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-sense-data dump.In that case please do the following:
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-
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-1. set the tape driver debug level to maximum:
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- echo 6 >/proc/s390dbf/tape/level
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-
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-2. re-perform the actions which produced the bug. (Hopefully the bug will
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- reappear.)
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-
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-3. get a snapshot from the debug-feature:
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- cat /proc/s390dbf/tape/hex_ascii >somefile
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-
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-4. Now put the snapshot together with a detailed description of the situation
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- that led to the bug:
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- - Which tool did you use?
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- - Which hardware do you have?
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- - Was your tape unit online?
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- - Is it a shared tape unit?
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-
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-5. Send an email with your bug report to:
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- mailto:Linux390@de.ibm.com
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-
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-
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Martin Schwidefsky