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net-1: paranoid queue checking to find more bugs.

configuration script version #1.

NFS filesystem client support by Rick Sladkey!

[Original announcement below]

0.99 has no major new features: the NFS client code is now in the
standard distribution, and the kernel configuration has changed, but
most of the rest of the changes are fixes - especially the tcp code
should now be pretty stable (knock wood).

Changes:

 - NFS is in. As are some stubs for the soud drivers, although it's only
   stubs right now.
 - various fixes around the place: the serial problems are hopefully
   gone, and there are patches to both TCP/IP and SCSI to make them more
   stable.
 - Minor fixes: the keyboard buglet introduced in 0.98pl6 should be
   gone, and some other bugs are also corrected.  The optimized
   read-ahead code in the filesystems (and the raw device read code) was
   too complicated and seemed to have problems with bad blocks, so I
   rewrote it, and it should hopefully work correctly now (this may have
   been the reason "mkfs -c" didn't work in all cases).  Thanks for some
   good bug-reports I've gotten: I've tried to correct all the problems
   I got reports on.
 - The kernel configuration has been re-thought: I decided to take
   advantage of the possibilities offered by GNU make etc.  This means
   that you no longer can compile the kernel using any other make, but
   there probably aren't many (if any) people doing that anyway.  This
   way I got rid of the extremely ugly SCSI setup, so it was probably
   worth it.

To configure the kernel for your setup, do a

        make config

and answer the yes/no questions. After that, do a

        make dep

to make the dependencies match your setup.  After that you should still
go edit the top-level Makefile for some of the configuration information
as before, but the remaining config things are pretty simple.  Then you
can make the kernel with a simple "make Image".

The new configuration utility (essentially a stupid shell script coupled
with some smarts in the Makefiles) tries to minimize compilations: if
you disable the SCSI code the scsi drivers won't even be compiled, much
less linked in.  This should be a win on slower machines.

NOTE!!! Use LILO-0.7 to load the 0.98pl5 and newer kernels: any older
version of lilo is liable to result in weird problems.

                Linus

Kai Makisara does the SCSI tape driver.  He's one of the few original
maintainers still around as such..

isofs introduced by Eric Youngdale, based on the minixfs code.  Eric was
a physicist, and you can tell he was new to C - he has been
Pascal-damaged, and has extra semi-colons at the end of block
statements.  But soon he ended up being one of the core maintainers
anyway, and took over SCSI maintenance.

More aggressive filesystem read-ahead introduced.

[Original announcement below]

Anyway, 0.98pl6 is hopefully the last release before 0.99: there are a
few known problems left in this release.  Most notable is the serial
code: it works for most people, but others still have problems with it.
I hope this will get fixed within a week (tytso is working on it).  It
also seems as if the PS/2 mouse code has some problems.

pl6 contains these fixes:

 - all the tcp/ip patches I've received (and I fixed one bug that
   gcc-2.3 seems to have found).
 - math-emu patch for the problem that resulted in FPU errors with some
   operations.
 - I fixed gcc-2.3 warnings as well as most of the old warnings.  You
   shouldn't get more than one or two warnings when recompiling the
   whole kernel.
 - /proc filesystem extensions.  Based on ideas (and some code) by
   Darren Senn, but mostly written by yours truly.  More about that
   later.
 - some tty_io fixes (there was a bug in the /dev/console handling when
   you changed VC's while using the general console device).
 - re-organization of the keyboard-driver internal data-structures.  The
   changes are mostly preliminary: they change the keyboard flags to be
   more easily adaptive to a reprogrammable keyboard driver.  No actual
   new features yet.
 - new SCSI drivers: reportedly much faster than the old ones (but not
   all drivers take advantage of it yet..)
 - various other fixes: pty's etc have minor changes.

I hope to make 0.99 in a week or so, and 1.0 after that has been tested
some.  I hope people will test out pl6 - 0.99 won't be much different,
and if you don't test pl6, any bugs relating to your particular hardware
may not be found in time for 0.99...

                Linus

Rename "malloc()/free()" as "kmalloc()/kfree()" to make people more
aware of some of the limitations.

Math emulator updates to handle the case that Linux (unlike the original
djgpp target) can get preempted by user space accesses.

Make "ll_rw_blk()" take an array of blocks to read/write.

VFS "notify_change()" callback, to allow the low-level filesystem to
decide what it wants to do about metadata changes.

Deprecate old "stat()" call by printing out a warning on use.

NR_OPEN is now 256 files per process, and the old "unsigned long" bitops
needed to go away. This causes lots of syntactic changes in select().

System call tracing implemented for ptrace().

[Original announcement below]

 - the inode caching bug (resulting in bad filesystem info when
   mounting/umounting devices) should be gone for good.

 - an elusive race-condition in the fs is fixed: this may have been the
   reason some people got fsck errors once in a while.  The
   race-condition was pretty hard to find, and depends on a lot of
   things (buffer cache size, speed of the disk and computer speed).

 - fpu emulator patches (mainly for the re-entrancy problem) by me and
   W. Metzenthen.

 - various wait-queue changes - the kernel uses the waiting mechanism
   more efficiently now.

 - the NFS client support code is there: the actual nfs code is still in
   alpha (although reported to be pretty stable) and has to be gotten
   separately.

 - NR_OPEN was changed from 32 to 256 (which is what SunOS seems to use,
   so I hope it won't need any further changes).  This has lead to some
   incompatibilities (GNU emacs and the term program seem to need
   recompilation to work correctly), as the 'select()' system call has a
   slightly changed interface due to the new fd_set definition.

 - the process kernel stack is now on a separate page (needed due to the
   fact that the task_struct has now grown to almost 3kB due to the
   NR_OPEN changes).  This also means 'ps' needs patches..  My patches
   to ps-0.98 are available as 'ps-diff.Z' in the same directory as the
   kernel sources and diffs.

 - various other changes: system call tracing by Ross Biro. Changed
   ll_rw_block interface (performance reasons: it will eventually be
   changed to accept several requests at once).  Malloc() was changed
   and renamed to kmalloc() due to the new interface.  Some tcp/ip
   patches (inode counting correction and some other changes).

0.98.4 should hopefully be pretty stable: the main problem areas are
probably still tcp/ip and some of the tty code.  I'd appreciate
comments, bug-reports etc.

                Linus

Start virtualizing real mmap() functionlity in the kernel.  The first
signs of me thinking about this already showed up as some unused header
files earlier, this fleshes things out some more.  No actual filesystem
code yet..

This also removes my old simple math emulator, and introduces the new
and much improved one from Bill Metzenthen.

Bill originally wrote it for the djgpp suite (DJ Delories gcc port to
DOS extenders).  It was much more accurate and well designed than my
hackish one, and I was happy to throw my old code away.  The new math
emulator also did things that I had never bothered with, notably the
more complex i387 functions (exponentials and trig).

I also fixed the static maximum memory limit: we now generate the kernel
page tables dynamically rather than having a 16M or 32M static limit.

SCSI updates: removable media support (which also implies re-reading the
partition table etc)

[Original announcement below]

patch-2 is >150kB compressed, as it contains several big changes. Most
notable are:

 - the new FPU-emulator by Bill Metzenthen.  It's bigger than the old
   one, but thanks to it, linux fpu emulation is no longer a quick hack,
   but a real emulator: it does all the 387(486) math instructions, and
   does them much faster than the old emulator + the soft library.

   The new math-emulator means that a separate soft-float library is no
   longer needed.  It also makes even a non-coprocessor system pretty
   useful for limited math-calcs - the complex functions are much faster
   when they no longer have to be calculated using simple functions, and
   even the simpler instructions that my old emulator handled are faster
   using the new one.

   The size of the new emulator may mean that people who have little
   RAM, but do have a coprocessor should probably recompile the kernel
   with the emulator disabled.

 - various minor mm fixes by me: trapping kernel NULL dereferences,
   cleaning up the page table initializations and the 16MB patches, and
   various other bugfixes.  get_free_page(GFP_ATOMIC) should preserve
   the interrupt flag, so malloc() should be safe now - hopefully no
   more of the tcp/ip memory management problems.

   The NULL pointer trapping may result in errors like:
        Unable to handle kernel paging request at address C0000???
        Oops: 0000
        ..... debugging info .....

   There were several NULL pointer dereferences in the serial and tty
   drivers, which should now be fixed.  I've also fixed any other errors
   I've seen, but if there are problems in the scsi drivers or similar
   things I cannot test, I'd like to hear about them.

 - scsi driver changes by Eric Youngdale.  Preliminary support for
   removable media, and some bug-fixes.  Due to white-space problems
   with eric's patches, the scsi patches are a bit bigger than
   necessary, but they should be ok even though I had to put them in
   partly by hand (and being unable to test them...)

 - The new tcp/ip patches that were sent to the NET channel not long
   ago.  Yes, they are alpha, but so is the whole tcp/ip directory, so I
   put them in even thought they haven't been extensively tested (and
   they did have a serious problem in the ioctl code, which I fixed).

 - psaux mouse patches by Dean Troyer, as well as the mouse.wait = NULL
   patch.

Before (or after) patching, you should remove the old math-emulator (ie
"rm -rf /usr/src/linux/kernel/math") as it is no longer needed.  You
should also do a "make dep" to update dependencies: as usual, I edited
out the dependancy-changes.  Do a "make clean", edit the main (and net)
Makefiles to suit your system, and compile.

And finally: I will no longer be making the bootdisks available -
they'll be made by hlu/jwinstead and will probably be boot+root-disks
using lilo, as done on the hlu disks.  That may mean that a bootimage
won't be available at once, but most people who want to use the
absolutely newest images probably compile them themselves anyway, so
that shouldn't be a problem.

                Linus

Ted Ts'o did extensive serial driver changes, and fixed up some of the
tty layer to match.  Tty's now allocated dynamically.

[Original announcement below]

This patch does not contain any major bug-fixes: it corrects named pipes
that broke with pl5, and has some minor changes in the IO-instructions
and the hd-driver, but those shouldn't matter for most of you.

It does contain all the scsi-patches that I've gotten so far, so if the
bootup sequence died on you in the scsi code, pl6 should correct this.

The major part of the patch is tytso's serial line changes, making the
tty structures dynamic.  No more NR_PTY's - the number of pty's is now
bounded only by the minor number setup (max 64 pty's) or the amount of
memory available (opening a pty requires a page of memory for tty
queues).  Similarly for serial lines.

The above just means that while pl6 can be useful, the changes to pl5
aren't big enough to worry about.  Most people don't use named pipes, it
seems, and the other changes are either cosmetic or hardware-dependent.
I still hope people upgrade, if only so that I can get new bug-reports.

I had hoped to release 0.98 this weekend, but studies and the scsi/hd
problems put an end to that.  0.98 should be out next weekend or so.
Expect the tcp/ip subdirectory and possibly some mm changes.

                Linus

We're making ready for big processes, and vm86 mode!
 - Move the kernel to virtual address 0xc0000000 instead of zero.
 - Allocate per-process page tables

We can now have 3GB processes, and more than 64 of them!

[Original announcement below]

As promised, 0.97.pl2 is out today (well, over here it's already
tomorrow, so I guess I'm 35 minutes late.  Naughty, naughty).  Right
now, the patch (and full source for those that don't like to patch up
the system) is available at "nic.funet.fi: pub/OS/Linux/testing/Linus",
but I'll try to put it on some other sites as well if I'm able and
energetic enough.  Probably tomorrow - together with a binary for those
that aren't willing to comple the kernel on their own.

0.97.2 has mostly my mm/fs patches, along with some relatively minor
diffs by others (including file locking by Doug Evans).  User-level
changes are minor: but the mm has changed a lot, and the vfs routines
have been changed to keep track of the error-messages a bit better.
Also, the vfs-interface to "follow_link()" changed slightly: people who
are making filesystems should look at the changes (but they are
relatively minor, and shouldn't result in any problems - both the
extended fs and minix fs needed just a simple change in their respective
symlink.c files).

The mm changes /might/ lower performance slightly, as the paging TLB's
are now flushed at every task-switch due to the new system, but I doubt
it's noticeable.  The other performance changes (dynamic buffers etc) in
0.97(.pl1) should overshadow that particular problem.

I hope this release means that these kinds of low-level rewrites aren't
needed for a while: the last couple of releases have changed some very
fundamental things.  Nothing seems to have suffered too badly, but I'd
be happier if it all got tested more thoroughly.  Anyway, discounting
the ps/free etc suite of programs, everything I have tried has worked
flawlessly despite the big kernel changes.

I'm still worried about the reports about messed-up buffers, but have
been unable to reproduce the problem, and nobody has so far
disillusioned me about my guess that it's a problem with the SCSI code
(which at least gives me an excuse for not doing anything about it :-).
Other problems include at least one report of spontaneous re-booting,
which is totally inexplicable, so I'm blaming hardware once more until I
can get better data on the thing.

As to patches sent by others: 0.97.2 contains very little of that kind
of code.  I've been too busy either working, or implementing my own
changes that I have simply ignored them for the most part.  Remind me
(or resend them relative to the new kernel) if you have a patch that is
still needed.

There is one new system call: 'vm86(struct vm86_struct * info)'.  It's
not ready for general use yet - it works, but will probably need some
tweaking before being practical.  But supporting a virtual 86 mode was
so easy after the mm rewrite that I felt it was worth implementing: the
vm86 code is less than 50 lines of C right now.

                Linus

PS.  The bright spot of the week goes to "The Oxford Beer Trolls" - all
UK inhabitants should probably be locked into some (big) mental
institution and TOBT should probably have a wing of their own, but
thanks to them linux can now call itself "beerware" :-)

Move <xxx.h> to <linux/xxxx.h>

Variable-sized buffer blocks and dynamic buffer cache allocation. The VM
knows how to shrink it automatically!

Add support for "fast" interrupt handlers for serial lines.

Update copyrights to say 1992 too.

Remove broken VESA video card handling.

Separate out partition handling code ("genhd").

Make init unkillable.

Norwegian keyboard map.

Future Domain SCSI controller driver by Rik Faith.

Changes in 0.97:

 - The VESA-support was removed.  I'd be happy to put it back once it
   works on all hardware.  Instead of the VESA-code, I finally put in
   the automatic SVGA setup patches.  See the top-level Makefile.

 - The IRQ code has solidified, and should work on all machines.  Not
   all of the SCSI drivers use it yet, so I expect patches for that..

 - Serial interrupts are handled slightly differently, and performance
   should be up.  I've sent out a few alpha-releases, and testing seems
   to indicate that's actually true this time.  Reactions have ranged
   from "nice" to "wonderful" :-)

 - The buffer-cache and memory management code has been edited quite a
   bit.  ps/free etc programs that reads kernel memory directly no
   longer work, and even a recompilation won't be enough.  They actually
   need editing before they work.

   The buffer-cache now grows and shrinks dynamically depending on how
   much free memory there is.  Shift+PrintScreen will give some memory
   statistics.  (Ctrl+PrSc gives task-info, ALT+PrSc gives current
   register values).

   The mm code changes removed some race-conditions in the VM code, and
   I also tried to make the Out-of-swapspace error less severe (better
   thrashing-detection etc).

 - The super-block code has been cleaned up.  Especially the extended fs
   needs to be edited a bit to take advantage of the new setup, and I
   expect Remy Card will have a patch out eventually.

 - include-files have been moved around some more: there are still some
   names that clash with the standard headers, but not many.

 - Unswappable processes implemented: by default only 'init' is
   unswappable.  This is a bit safer in low-memory conditions, as at
   least init won't die due to low memory.  I also made killing init
   impossible: if init doesn't recognize a signal, it simply won't get
   it.  Some other changes ("while (1) fork();" won't kill the machine
   for non-root users etc)

 - The new SCSI drivers are in.  These make the kernel noticeably
   bigger, but you can leave them out if you don't want them.

 - The floppy- and hd-drivers print out more debugging-info in case of
   errors: this might be irritating if you have hardware that works, but
   often gives soft-errors.  On the other hand, some old debugging-info
   was removed - notably for user-level protection errors etc.

 - Various minor fixes.  I haven't made cdiffs (and I haven't gotten any
   requests for them, so I probably never will), but they would be
   pretty big.

Things that I didn't have time for:

 - I wanted to rewrite the tty drivers to be more "streams-like" (ie not
   an actual streams-implementation, but some of the ideas from
   streams).  I never got around to it: there was simply too much else
   to do.

 - I got a lot of patches, and some went in, others didn't.  If you
   think your patch was important, please re-send it relative to the new
   version.

I'd like comments on the new system: performance / clarity of code etc.
0.97 should correct all known bugs (at least the ones I know about), but
I guess that's just wishful thinking.

Note that the dynamic buffer-code also handles differently-sized
buffers, but that the rest of the system (block device drivers,
filesystem code etc) cannot yet take advantage of this - there is still
some coding needed.

		Linus

More VFS layer work: remove more special cases, and take advantage of
the virtual VFS functions (close and select).  Add fchown/fchgrp and
[f]truncate.

Orest Zborowski shows up, and works on porting X11 to X.  This needs a
lot of infrastructure support: ioperm() for user-mode IO port access,
and SVR style virtual terminal ioctl's to make porting easier.  Perhaps
more importantly, the mmap() system call shows up, even if it right now
is limited only to a direct /dev/mem remapping.

[Original changelog below]

- truncate/ftruncate/fchmod/fchown system calls

        note that there aren't any library functions for these, so they
        aren't very useful yet...

        [f]truncate needed a change in the logic of the internal
        truncate VFS call - anybody that has any nonstandard filesystem
        probably needs to look it up.

- io-bitmap syscalls giving root-processes access to selected io ports
  from user space.  There is a "ioperm()" system call that lets the
  process select which ports it wants to enable/disable (all ports
  disabled as default) as well as a (standard sysv?) ioctl interface
  that X uses.

        again, no library stubs, but it allows things like reading and
        setting the cmos clock without using /dev/port, as well as
        control over the VGA registers...

- mmap for /dev/mem

        more things needed for X...

- the signal-handling fixes needed for gdb

        These aren't yet complete: serial lines still send signals under
        interrupts that can result in problems (ie ptrace doesn't
        correctly get them), but that's pretty unlikely (and will be
        fixed in the final 0.96).  Breakpoints should work etc..

- multiple shared libraries

        Up to 6 simultaneous shared libraries/process: the patches were
        originally by pmacdona, but they were heavily changed by me, and
        I think they work in a more natural manner now.  One user-level
        change is that the libraries are now checked for read and
        execute permissions for safety-reasons.

- cleaned up special files.

        read/write/ioctl no longer has special-case code: it is all
        handled with tables to functions.  This will mean that the SCSI
        patches won't patch in quite cleanly into 0.96: you'll need to
        add the code that sets up the functions.

        Again: device drivers and vfs-filesystem hackers need to look
        into the changes, although they are pretty logical (earlier
        versions just didn't implement all the vfs-routines)

        Note that the vfs-code for select is still not used: select is
        hardcoded for the devices it supports right now.

- ptrace() has a new interface

        as gdb for versions < 0.95c don't work on the new version, and
        gdb won't work very well at all on 0.95c[+], there was no reason
        not to break ptrace.  Thus 0.96 has a new calling convention for
        ptrace, and the old ptrace library function no longer works.
        I'm including the new ptrace library function at the end of this
        post.

- mount() takes 4 arguments, and checks that only the super-user can
  mount/umount things.

        Happily this shouldn't break any old binaries.

- some general cleanups

The subject pretty much says it all: I've sent out the "weekly patch"
and I'd be very interested in comments. As with patch1, there are some
very fundamental changes in the kernel, and they might have some
problems. I'd want as many as possible to test out linux-0.96c.pl2, as
that has always been the best way to test out the changes. Everything
works on my machine, but that doesn't guarantee it will work on other
setups...

The MAJOR change in 0.96c.pl2 is the totally rewritten sleep/wakeup
code. That, together with the IRQ code introduced in pl1 and slightly
edited in pl2, means that two very fundamental things in the linux
kernel have changed in the last two weeks. The code is cleaner, easier
to add devices to, and hopefully faster, but it's still a bit risky to
change this kind of very low-level behaviour.

Select() is now implemented using the vfs jump tables, and thanks to the
better sleep/wakup interface, select() performance should be noticeably
better. At least xload seems to give lower load-averages, and I hope
ka9q will work better with the new kernel. Note that things like the
tty code doesn't yet take full advantage of the new features the
rewritten sleep offers, but I wanted to get a good testing-release out
before actually tweaking all the routines to use the new interface.

The IRQ routines have changed slightly, and all known bugs are fixed.

While I'm most interested to hear comments about the IRQ and
select/sleep/wakup code, there are a few other changes in pl2:

 - Swiss keyboard support.

 - Screen blanking now only reacts to key-presses and kernel messages:
normal tty output doesn't make the screen unblank.

 - DOS-fs version 5 is in. It wouldn't hurt to try it out. It's
somewhat alpha still, but it seems to work. mtools should be a thing of
the past once the dosfs is a bit more tested.

 - core-file magic number, and a minor bug in ptrace is fixed

 - a bus-mouse is supported. I'd like to hear if it still works after I
did the select() patches "blind" (I can't test it on my machine).

 - iopl changing is possible (but requires root priviledges): this
allows access to all IO ports, as well as the interrupt flag. Don't use
it unless /absolutely/ necessary: a bug in your program will most likely
crash the machine if you are running with IO priviledges. It's needed
for some X VGA drivers.

As a result of all the changes, the diff is pretty big. Apply and build
it with something like:

        cd /usr/src
        zcat linux-0.96c.patch2.Z | patch -p0
        cd linux
        make dep
        make clean
        make Image

assuming you have the 0.96c.pl1 kernel in /usr/src/linux. I've had some
reports that my patches won't always go in cleanly: I know for a fact
that patch1 patches cleanly (I rebuilt 0.96c.pl1 by downloading it all
from banjo), so the error is in your end.

Possible problems:

 - The VESA code in setup.S has some problems. I haven't even looked
into it yet, so if it won't work for you, please either (a) use the
unpatched setup.S from 0.96c, or (b) try to find the problem and tell
me. (b) is preferable, of course. I'd like to have VESA support, but
if the bug isn't found, I'll have to use the non-VESA version for 0.97.

 - The IRQ code in 0.96c.pl1 could overrun the stack if linux got
un-ending interrupt requests, resulting in a re-boot. With pl2, this
shouldn't happen: linux should print out something like "Recursive
interrupt on IRQx. Shutting down" and simply disable the problematic
IRQ line. If you see this message, I'd be very interested to hear about
it (which IRQ, what devices you have, etc).

 - And any new or old bugs I haven't found yet.

I have one report that 0.96c.pl1 has problems with the inode table, and
panics on bootup with a "no more inodes in mem" report. Can anybody
confirm this sighting? I haven't found the reason for it, and haven't
seen it myself. I'm hoping it's an installation problem, but if anybody
else sees the same behaviour, I'm SOL.

            Linus