mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-16 01:04:08 +08:00
1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
308 lines
11 KiB
Plaintext
308 lines
11 KiB
Plaintext
Intro
|
|
=====
|
|
|
|
This file describes some issues involved when using the "ftape"
|
|
floppy tape device driver that comes with the Linux kernel.
|
|
|
|
ftape has a home page at
|
|
|
|
http://ftape.dot-heine.de/
|
|
|
|
which contains further information about ftape. Please cross check
|
|
this WWW address against the address given (if any) in the MAINTAINERS
|
|
file located in the top level directory of the Linux kernel source
|
|
tree.
|
|
|
|
NOTE: This is an unmaintained set of drivers, and it is not guaranteed to work.
|
|
If you are interested in taking over maintenance, contact Claus-Justus Heine
|
|
<ch@dot-heine.de>, the former maintainer.
|
|
|
|
Contents
|
|
========
|
|
|
|
A minus 1: Ftape documentation
|
|
|
|
A. Changes
|
|
1. Goal
|
|
2. I/O Block Size
|
|
3. Write Access when not at EOD (End Of Data) or BOT (Begin Of Tape)
|
|
4. Formatting
|
|
5. Interchanging cartridges with other operating systems
|
|
|
|
B. Debugging Output
|
|
1. Introduction
|
|
2. Tuning the debugging output
|
|
|
|
C. Boot and load time configuration
|
|
1. Setting boot time parameters
|
|
2. Module load time parameters
|
|
3. Ftape boot- and load time options
|
|
4. Example kernel parameter setting
|
|
5. Example module parameter setting
|
|
|
|
D. Support and contacts
|
|
|
|
*******************************************************************************
|
|
|
|
A minus 1. Ftape documentation
|
|
==============================
|
|
|
|
Unluckily, the ftape-HOWTO is out of date. This really needs to be
|
|
changed. Up to date documentation as well as recent development
|
|
versions of ftape and useful links to related topics can be found at
|
|
the ftape home page at
|
|
|
|
http://ftape.dot-heine.de/
|
|
|
|
*******************************************************************************
|
|
|
|
A. Changes
|
|
==========
|
|
|
|
1. Goal
|
|
~~~~
|
|
The goal of all that incompatibilities was to give ftape an interface
|
|
that resembles the interface provided by SCSI tape drives as close
|
|
as possible. Thus any Unix backup program that is known to work
|
|
with SCSI tape drives should also work.
|
|
|
|
The concept of a fixed block size for read/write transfers is
|
|
rather unrelated to this SCSI tape compatibility at the file system
|
|
interface level. It developed out of a feature of zftape, a
|
|
block wise user transparent on-the-fly compression. That compression
|
|
support will not be dropped in future releases for compatibility
|
|
reasons with previous releases of zftape.
|
|
|
|
2. I/O Block Size
|
|
~~~~~~~~~~~~~~
|
|
The block size defaults to 10k which is the default block size of
|
|
GNU tar.
|
|
|
|
The block size can be tuned either during kernel configuration or
|
|
at runtime with the MTIOCTOP ioctl using the MTSETBLK operation
|
|
(i.e. do "mt -f /dev/qft0" setblk #BLKSZ). A block size of 0
|
|
switches to variable block size mode i.e. "mt setblk 0" switches
|
|
off the block size restriction. However, this disables zftape's
|
|
built in on-the-fly compression which doesn't work with variable
|
|
block size mode.
|
|
|
|
The BLKSZ parameter must be given as a byte count and must be a
|
|
multiple of 32k or 0, i.e. use "mt setblk 32768" to switch to a
|
|
block size of 32k.
|
|
|
|
The typical symptom of a block size mismatch is an "invalid
|
|
argument" error message.
|
|
|
|
3. Write Access when not at EOD (End Of Data) or BOT (Begin Of Tape)
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
zftape (the file system interface of ftape-3.x) denies write access
|
|
to the tape cartridge when it isn't positioned either at BOT or
|
|
EOD.
|
|
|
|
4. Formatting
|
|
~~~~~~~~~~
|
|
ftape DOES support formatting of floppy tape cartridges. You need the
|
|
`ftformat' program that is shipped with the modules version of ftape.
|
|
Please get the latest version of ftape from
|
|
|
|
ftp://sunsite.unc.edu/pub/Linux/kernel/tapes
|
|
|
|
or from the ftape home page at
|
|
|
|
http://ftape.dot-heine.de/
|
|
|
|
`ftformat' is contained in the `./contrib/' subdirectory of that
|
|
separate ftape package.
|
|
|
|
5. Interchanging cartridges with other operating systems
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
The internal emulation of Unix tape device file marks has changed
|
|
completely. ftape now uses the volume table segment as specified
|
|
by the QIC-40/80/3010/3020/113 standards to emulate file marks. As
|
|
a consequence there is limited support to interchange cartridges
|
|
with other operating systems.
|
|
|
|
To be more precise: ftape will detect volumes written by other OS's
|
|
programs and other OS's programs will detect volumes written by
|
|
ftape.
|
|
|
|
However, it isn't possible to extract the data dumped to the tape
|
|
by some MSDOS program with ftape. This exceeds the scope of a
|
|
kernel device driver. If you need such functionality, then go ahead
|
|
and write a user space utility that is able to do that. ftape already
|
|
provides all kernel level support necessary to do that.
|
|
|
|
*******************************************************************************
|
|
|
|
B. Debugging Output
|
|
================
|
|
|
|
1. Introduction
|
|
~~~~~~~~~~~~
|
|
The ftape driver can be very noisy in that is can print lots of
|
|
debugging messages to the kernel log files and the system console.
|
|
While this is useful for debugging it might be annoying during
|
|
normal use and enlarges the size of the driver by several kilobytes.
|
|
|
|
To reduce the size of the driver you can trim the maximal amount of
|
|
debugging information available during kernel configuration. Please
|
|
refer to the kernel configuration script and its on-line help
|
|
functionality.
|
|
|
|
The amount of debugging output maps to the "tracing" boot time
|
|
option and the "ft_tracing" modules option as follows:
|
|
|
|
0 bugs
|
|
1 + errors (with call-stack dump)
|
|
2 + warnings
|
|
3 + information
|
|
4 + more information
|
|
5 + program flow
|
|
6 + fdc/dma info
|
|
7 + data flow
|
|
8 + everything else
|
|
|
|
2. Tuning the debugging output
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
To reduce the amount of debugging output printed to the system
|
|
console you can
|
|
|
|
i) trim the debugging output at run-time with
|
|
|
|
mt -f /dev/nqft0 setdensity #DBGLVL
|
|
|
|
where "#DBGLVL" is a number between 0 and 9
|
|
|
|
ii) trim the debugging output at module load time with
|
|
|
|
modprobe ftape ft_tracing=#DBGLVL
|
|
|
|
Of course, this applies only if you have configured ftape to be
|
|
compiled as a module.
|
|
|
|
iii) trim the debugging output during system boot time. Add the
|
|
following to the kernel command line:
|
|
|
|
ftape=#DBGLVL,tracing
|
|
|
|
Please refer also to the next section if you don't know how to
|
|
set boot time parameters.
|
|
|
|
*******************************************************************************
|
|
|
|
C. Boot and load time configuration
|
|
================================
|
|
|
|
1. Setting boot time parameters
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
Assuming that you use lilo, the LI)nux LO)ader, boot time kernel
|
|
parameters can be set by adding a line
|
|
|
|
append some_kernel_boot_time_parameter
|
|
|
|
to `/etc/lilo.conf' or at real boot time by typing in the options
|
|
at the prompt provided by LILO. I can't give you advice on how to
|
|
specify those parameters with other loaders as I don't use them.
|
|
|
|
For ftape, each "some_kernel_boot_time_parameter" looks like
|
|
"ftape=value,option". As an example, the debugging output can be
|
|
increased with
|
|
|
|
ftape=4,tracing
|
|
|
|
NOTE: the value precedes the option name.
|
|
|
|
2. Module load time parameters
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
Module parameters can be specified either directly when invoking
|
|
the program 'modprobe' at the shell prompt:
|
|
|
|
modprobe ftape ft_tracing=4
|
|
|
|
or by editing the file `/etc/modprobe.conf' in which case they take
|
|
effect each time when the module is loaded with `modprobe' (please
|
|
refer to the respective manual pages). Thus, you should add a line
|
|
|
|
options ftape ft_tracing=4
|
|
|
|
to `/etc/modprobe.conf` if you intend to increase the debugging
|
|
output of the driver.
|
|
|
|
|
|
3. Ftape boot- and load time options
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
|
|
i. Controlling the amount of debugging output
|
|
DBGLVL has to be replaced by a number between 0 and 8.
|
|
|
|
module | kernel command line
|
|
-----------------------|----------------------
|
|
ft_tracing=DBGLVL | ftape=DBGLVL,tracing
|
|
|
|
ii. Hardware setup
|
|
BASE is the base address of your floppy disk controller,
|
|
IRQ and DMA give its interrupt and DMA channel, respectively.
|
|
BOOL is an integer, "0" means "no"; any other value means
|
|
"yes". You don't need to specify anything if connecting your tape
|
|
drive to the standard floppy disk controller. All of these
|
|
values have reasonable defaults. The defaults can be modified
|
|
during kernel configuration, i.e. while running "make config",
|
|
"make menuconfig" or "make xconfig" in the top level directory
|
|
of the Linux kernel source tree. Please refer also to the on
|
|
line documentation provided during that kernel configuration
|
|
process.
|
|
|
|
ft_probe_fc10 is set to a non-zero value if you wish for ftape to
|
|
probe for a Colorado FC-10 or FC-20 controller.
|
|
|
|
ft_mach2 is set to a non-zero value if you wish for ftape to probe
|
|
for a Mountain MACH-2 controller.
|
|
|
|
module | kernel command line
|
|
-----------------------|----------------------
|
|
ft_fdc_base=BASE | ftape=BASE,ioport
|
|
ft_fdc_irq=IRQ | ftape=IRQ,irq
|
|
ft_fdc_dma=DMA | ftape=DMA,dma
|
|
ft_probe_fc10=BOOL | ftape=BOOL,fc10
|
|
ft_mach2=BOOL | ftape=BOOL,mach2
|
|
ft_fdc_threshold=THR | ftape=THR,threshold
|
|
ft_fdc_rate_limit=RATE | ftape=RATE,datarate
|
|
|
|
4. Example kernel parameter setting
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
To configure ftape to probe for a Colorado FC-10/FC-20 controller
|
|
and to increase the amount of debugging output a little bit, add
|
|
the following line to `/etc/lilo.conf':
|
|
|
|
append ftape=1,fc10 ftape=4,tracing
|
|
|
|
5. Example module parameter setting
|
|
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
|
To do the same, but with ftape compiled as a loadable kernel
|
|
module, add the following line to `/etc/modprobe.conf':
|
|
|
|
options ftape ft_probe_fc10=1 ft_tracing=4
|
|
|
|
*******************************************************************************
|
|
|
|
D. Support and contacts
|
|
====================
|
|
|
|
Ftape is distributed under the GNU General Public License. There is
|
|
absolutely no warranty for this software. However, you can reach
|
|
the current maintainer of the ftape package under the email address
|
|
given in the MAINTAINERS file which is located in the top level
|
|
directory of the Linux kernel source tree. There you'll find also
|
|
the relevant mailing list to use as a discussion forum and the web
|
|
page to query for the most recent documentation, related work and
|
|
development versions of ftape.
|
|
|
|
Changelog:
|
|
==========
|
|
|
|
~1996: Original Document
|
|
|
|
10-24-2004: General cleanup and updating, noting additional module options.
|
|
James Nelson <james4765@gmail.com>
|