Commit Graph

314 Commits

Author SHA1 Message Date
Jeff Dike 4cffb7fa69 [PATCH] uml: SIGIO formatting fixes
Fix formatting in the sigio code.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:23 -08:00
Jeff Dike 73c8f4441f [PATCH] uml: libc-dependent code should call libc directly
We shouldn't be using the os wrappers from os code - we can use libc directly.
This patch replaces wrapper calls with libc calls.

It turns out that os_sigio_async had only one caller, which was in startup.c,
so that function is moved there and its name changed.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:23 -08:00
Jeff Dike 6bf79482f3 [PATCH] uml: locking comments in memory and tempfile code
Locking comments and emacs comment removal in the low-level memory and
temp file code.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:23 -08:00
Jeff Dike 27aa6ef3c0 [PATCH] uml: make signal handlers static
A bunch of the signal handlers can be made static.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:22 -08:00
Jeff Dike 6d1b18b16f [PATCH] uml: remove unused variable and function
syscall_index and next_syscall_index turn out not to be used.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:22 -08:00
Jeff Dike c6256c6824 [PATCH] uml: fix previous console locking
Eliminate the open_mutex after complaints from Blaisorblade.  It turns out
that the tty count provides the information needed to tell whether we are the
first opener or last closer.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:22 -08:00
Jeff Dike d5c9ffc6c6 [PATCH] uml: console locking commentary and code cleanup
Remove the last vestiges of devfs from console registration.  Change the name
of the function, plus remove a couple of unused fields from the line_driver
structure.

struct lines is no longer needed, all traces of it are gone.

The only way that I can see to mark a structure as being almost-const is to
individually const the fields.  This is the case for the line_driver
structure, which has only one modifiable field - a list_head in a
sub-structure.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:22 -08:00
Jeff Dike b4ac91a0ea [PATCH] uml: chan_user.h formatting fixes
Whitespace fixes and emacs comment removal.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:22 -08:00
Jeff Dike a52f362f86 [PATCH] uml: mostly const a structure
The chan_opts structure is mostly const, and needs no locking.  Comment the
lack of locking on the one field that can change.

Make all the other fields const.  It turned out that console_open_chan didn't
use its chan_opts argument, so that is deleted from the function and its
callers.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:22 -08:00
Jeff Dike 4ea21cd917 [PATCH] uml: network driver whitespace and style fixes
Some whitespace and coding style cleanups in the network driver code.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:21 -08:00
Jeff Dike d3b7f69de2 [PATCH] uml: add locking to network transport registration
The registration of host network transports needed some locking.  The
transport list itself is locked, but calls to the registration routines are
not.  This is compensated for by checking that a transport structure is not
yet on any list.

I also took the opportunity to const all fields in the transport structure
except the list, which obviously can be modified.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:21 -08:00
Jeff Dike 894be2a485 [PATCH] uml: console whitespace and comment tidying
Some comment and whitespace cleanups in the console and mconsole code.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:21 -08:00
Jeff Dike f28169d200 [PATCH] uml: return hotplug errors to host
I noticed that errors happening while hotplugging devices from the host were
never returned back to the mconsole client.  In some cases, success was
returned instead of even an information-free error.

This patch cleans that up by having the low-level configuration code pass back
an error string along with an error code.  At the top level, which knows
whether it is early boot time or responding to an mconsole request, the string
is printk'd or returned to the mconsole client.

There are also whitespace and trivial code cleanups in the surrounding code.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:21 -08:00
Jeff Dike d79a580936 [PATCH] uml: console locking fixes
Clean up the console driver locking.  There are various problems here,
including sleeping under a spinlock and spinlock recursion, some of which are
fixed here.  This patch deals with the locking involved with opens and closes.
 The problem is that an mconsole request to change a console's configuration
can race with an open.  Changing a configuration should only be done when a
console isn't opened.  Also, an open must be looking at a stable
configuration.  In addition, a get configuration request must observe the same
locking since it must also see a stable configuration.  With the old locking,
it was possible for this to hang indefinitely in some cases because open would
block for a long time waiting for a connection from the host while holding the
lock needed by the mconsole request.

As explained in the long comment, this is fixed by adding a spinlock for the
use count and configuration and a mutex for the actual open and close.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:21 -08:00
Peter Zijlstra eff3b634d9 [PATCH] uml: fix net_kern workqueue abuse
Fix up the work on stack and exit scope trouble by placing the work_struct
in the uml_net_private data.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-13 09:05:47 -08:00
Alan Cox 606d099cdd [PATCH] tty: switch to ktermios
This is the grungy swap all the occurrences in the right places patch that
goes with the updates.  At this point we have the same functionality as
before (except that sgttyb() returns speeds not zero) and are ready to
begin turning new stuff on providing nobody reports lots of bugs

If you are a tty driver author converting an out of tree driver the only
impact should be termios->ktermios name changes for the speed/property
setting functions from your upper layers.

If you are implementing your own TCGETS function before then your driver
was broken already and its about to get a whole lot more painful for you so
please fix it 8)

Also fill in c_ispeed/ospeed on init for most devices, although the current
code will do this for you anyway but I'd like eventually to lose that extra
paranoia

[akpm@osdl.org: bluetooth fix]
[mp3@de.ibm.com: sclp fix]
[mp3@de.ibm.com: warning fix for tty3270]
[hugh@veritas.com: fix tty_ioctl powerpc build]
[jdike@addtoit.com: uml: fix ->set_termios declaration]
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Martin Peschke <mp3@de.ibm.com>
Acked-by: Peter Oberparleiter <oberpar@de.ibm.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08 08:28:57 -08:00
Jeff Dike e46962fdd2 [PATCH] uml: size register files correctly
We were using the wrong symbol to size register files.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:29 -08:00
Jeff Dike 7b65fee21c [PATCH] uml: include asm/page.h in order to get PAGE_SHIFT
Include the proper header to get a definition of PAGE_SHIFT.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:29 -08:00
Andrew Morton a2ce774096 [PATCH] uml: workqueue build fix
arch/um/drivers/chan_kern.c:643: error: conflicting types for 'chan_interrupt'
  arch/um/include/chan_kern.h:31: error: previous declaration of 'chan_interrupt'

Cc: David Howells <dhowells@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:20 -08:00
Al Viro abf419b809 [NET]: UML checksum annotations and cleanups.
* sanitize prototypes, annotate
* kill csum_partial_copy_fromuser
* kill shift-by-16 in checksum calculations
* ntohs->shift in checksum calculations

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02 21:23:12 -08:00
Paolo 'Blaisorblade' Giarrusso 5d48545e5e [PATCH] uml: make execvp safe for our usage
Reimplement execvp for our purposes - after we call fork() it is fundamentally
unsafe to use the kernel allocator - current is not valid there.  So we simply
pass to our modified execvp() a preallocated buffer.  This fixes a real bug
and works very well in testing (I've seen indirectly warning messages from the
forked thread - they went on the pipe connected to its stdout and where read
as a number by UML, when calling read_output().  I verified the obtained
number corresponded to "BUG:").

The added use of __cant_sleep() is not a new bug since __cant_sleep() is
already used in the same function - passing an atomicity parameter would be
better but it would require huge change, stating that this function must not
be called in atomic context and can sleep is a better idea (will make sure of
this gradually).

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-25 13:28:34 -08:00
Jeff Dike 53b173327d [PATCH] uml: fix I/O hang
Fix a UML hang in which everything would just stop until some I/O happened
- a ping, someone whacking the keyboard - at which point everything would
start up again as though nothing had happened.

The cause was gcc reordering some code which absolutely needed to be
executed in the order in the source.  When unblock_signals switches signals
from off to on, it needs to see if any interrupts had happened in the
critical section.  The interrupt handlers check signals_enabled - if it is
zero, then the handler adds a bit to the "pending" bitmask and returns.
unblock_signals checks this mask to see if any signals need to be
delivered.

The crucial part is this:
	signals_enabled = 1;
	save_pending = pending;
	if(save_pending == 0)
		return;
	pending = 0;

In order to avoid an interrupt arriving between reading pending and setting
it to zero, in which case, the record of the interrupt would be erased,
signals are enabled.

What happened was that gcc reordered this so that 'save_pending = pending'
came before 'signals_enabled = 1', creating a one-instruction window within
which an interrupt could arrive, set its bit in pending, and have it be
immediately erased.

When the I/O workload is purely disk-based, the loss of a block device
interrupt stops the entire I/O system because the next block request will
wait for the current one to finish.  Thus the system hangs until something
else causes some I/O to arrive, such as a network packet or console input.

The fix to this particular problem is a memory barrier between enabling
signals and reading the pending signal mask.  An xchg would also probably
work.

Looking over this code for similar problems led me to do a few more
things:

- make signals_enabled and pending volatile so that they don't get cached
  in registers

- add an mb() to the return paths of block_signals and unblock_signals so
  that the modification of signals_enabled doesn't get shuffled into the
  caller in the event that these are inlined in the future.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-03 12:27:58 -08:00
Paolo 'Blaisorblade' Giarrusso d8d7c28ec0 [PATCH] uml ubd driver: various little changes
Fix a small memory leak in ubd_config, and clearify the confusion which lead
to it.

Then, some little changes not affecting operations -
* move init functions together,
* add a comment about a potential problem in case of some evolution in the block layer,
* mark all initcalls as static __init functions
* mark an used once little function as inline
* document that mconsole methods are all called in process context (was
  triggered when checking ubd mconsole methods).

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-31 08:07:00 -08:00
Al Viro 3a51237dc1 [PATCH] uml: mconsole fixes
* when we have stop/sysrq/go, we get pt_regs of whatever executes
   mc_work_proc().  Would be better to see what we had at the time of
   interrupt that got us stop.

 * stop/stop/stop.....  will give stack overflow.  Shouldn't allow stop
   from mconsole_stop().

 * stop/stop/go leaves us inside mconsole_stop() with
	os_set_fd_block(req->originating_fd, 0);
	reactivate_fd(req->originating_fd, MCONSOLE_IRQ);
   just done by nested mconsole_stop().  Ditto.

 * once we'd seen stop, there's a period when INTR commands are executed
   out of order (as they should; we might have the things stuck badly
   enough to never reach mconsole_stop(), but still not badly enough to
   block mconsole_interrupt(); in that situation we _want_ things like
   "cad" to be executed immediately).  Once we enter monsole_stop(), all
   INTR commands will be executed in order, mixed with PROC ones.  We'd
   better let user see that such change of behaviour has happened.
   (Suggested by lennert).

 * stack footprint of monsole_interrupt() is an atrocity; AFAICS we can
   safely make struct mc_request req; static in function there.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-24 22:01:10 -07:00
Paolo 'Blaisorblade' Giarrusso c13e569073 [PATCH] uml: split memory allocation prototypes out of user.h
user.h is too generic a header name.  I've split out allocation routines from
it.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-20 10:26:36 -07:00
Ulrich Drepper 51018b0a31 [PATCH] make UML compile (FC6/x86-64)
I need this patch to get a UML kernel to compile.  This is with the
kernel headers in FC6 which are automatically generated from the kernel
tree.  Some headers are missing but those files don't need them.  At
least it appears so since the resuling kernel works fine.

Tested on x86-64.

Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-15 14:18:39 -07:00
Paolo 'Blaisorblade' Giarrusso d27ecef7c6 [PATCH] uml: asm offsets duplication removal
Unify macros common to x86 and x86_64 kernel-offsets.h files.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-11 11:14:20 -07:00
Paolo 'Blaisorblade' Giarrusso 2465b8580a [PATCH] uml: allow using again x86/x86_64 crypto code
Enable compilation of x86_64 crypto code;, and add the needed constant to make
the code compile again (that macro was added to i386 asm-offsets between
2.6.17 and 2.6.18, in 6c2bb98bc3).

Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-11 11:14:20 -07:00
Paolo 'Blaisorblade' Giarrusso b5cdb5797d [PATCH] uml: make UML_SETJMP always safe
If enable is moved by GCC in a register its value may not be preserved after
coming back there with longjmp().  So, mark it as volatile to prevent this;
this is suggested (it seems) in info gcc, when it talks about -Wuninitialized.
 I re-read this and it seems to say something different, but I still believe
this may be needed.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-11 11:14:20 -07:00
Paolo 'Blaisorblade' Giarrusso e27e80b3da [PATCH] uml: readd forgot prototype
This was forgot in a previous patch so UML does not compile with TT mode
enabled.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-11 11:14:20 -07:00
David Howells 40220c1a19 IRQ: Use the new typedef for interrupt handler function pointers
Use the new typedef for interrupt handler function pointers rather than
actually spelling out the full thing each time.  This was scripted with the
following small shell script:

#!/bin/sh
egrep -nHrl -e 'irqreturn_t[ 	]*[(][*]' $* |
while read i
do
    echo $i
    perl -pi -e 's/irqreturn_t\s*[(]\s*[*]\s*([_a-zA-Z0-9]*)\s*[)]\s*[(]\s*int\s*,\s*void\s*[*]\s*[)]/irq_handler_t \1/g' $i || exit $?
done

Signed-Off-By: David Howells <dhowells@redhat.com>
2006-10-09 12:19:47 +01:00
Al Viro 7bea96fd22 [PATCH] uml pt_regs fixes
Real fix for UML pt_regs stuff.  Note set_irq_regs() logics in there...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-08 16:34:08 -07:00
Dave Jones 038b0a6d8d Remove all inclusions of <linux/config.h>
kbuild explicitly includes this at build time.

Signed-off-by: Dave Jones <davej@redhat.com>
2006-10-04 03:38:54 -04:00
Matt LaPlante 4b3f686d4a Attack of "the the"s in arch
The patch below corrects multiple occurances of "the the"
typos across several files, both in source comments and KConfig files.
There is no actual code changed, only text.  Note this only affects the /arch
directory, and I believe I could find many more elsewhere. :)

Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-10-03 22:21:02 +02:00
Jeff Dike b68e31d0eb [PATCH] const struct tty_operations
As part of an SMP cleanliness pass over UML, I consted a bunch of
structures in order to not have to document their locking.  One of these
structures was a struct tty_operations.  In order to const it in UML
without introducing compiler complaints, the declaration of
tty_set_operations needs to be changed, and then all of its callers need to
be fixed.

This patch declares all struct tty_operations in the tree as const.  In all
cases, they are static and used only as input to tty_set_operations.  As an
extra check, I ran an i386 allyesconfig build which produced no extra
warnings.

53 drivers are affected.  I checked the history of a bunch of them, and in
most cases, there have been only a handful of maintenance changes in the
last six months.  serial_core.c was the busiest one that I looked at.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-02 07:57:14 -07:00
Jeff Dike fade5d5461 [PATCH] uml: don't roll my own random MAC generator
Use the existing random_ether_addr() instead of cooking up my own
version.  Pointed out by Dave Hollis and Jason Lunz.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:04 -07:00
Jeff Dike b10aeeef55 [PATCH] uml: mechanical tidying after random MACs change
Mechanical, hopefully non-functional changes stemming from
setup_etheraddr always succeeding now that it always assigns a MAC,
either from the command line or generated randomly:
   the test of the return of setup_etheraddr is removed, and code
dependent on it succeeding is now unconditional
   setup_etheraddr can now be made void
   struct uml_net.have_mac is now always 1, so tests of it can be
similarly removed, and uses of it can be replaced with 1
   struct uml_net.have_mac is no longer used, so it can be removed
   struct uml_net_private.have_mac is copied from struct uml_net, so
it is always 1
   tests of uml_net_private.have_mac can be removed
   uml_net_private.have_mac can now be removed
   the only call to dev_ip_addr was removed, so it can be deleted

It also turns out that setup_etheraddr is called only once, from the same
file, so it can be static and its declaration removed from net_kern.h.

Similarly, set_ether_mac is defined and called only from one file.

Finally, setup_etheraddr and set_ether_mac were moved to avoid needing forward
declarations.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:04 -07:00
Jeff Dike f3e7ed2b61 [PATCH] uml: assign random MACs to interfaces if necessary
Assign a random MAC to an ethernet interface if one was not provided on the
command line.  This became pressing when distros started bringing interfaces
up before assigning IPs to them.  The previous pattern of assigning an IP then
bringing it up allowed the MAC to be generated from the first IP assigned.
However, once the thing is up, it's probably a bad idea to change the MAC, so
the MAC stayed initialized to fe:fd:0:0:0:0.

Now, if there is no MAC from the command line, one is generated.  We use the
microseconds from gettimeofday (20 bits), plus the low 12 bits of the pid to
seed the random number generator.  random() is called twice, with 16 bits of
each result used.  I didn't want to have to try to fill in 32 bits optimally
given an arbitrary RAND_MAX, so I just assume that it is greater than 65536
and use 16 bits of each random() return.

There is also a bit of reformatting and whitespace cleanup here.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:04 -07:00
Jeff Dike 3c91735099 [PATCH] uml: thread creation tidying
fork on UML has always somewhat subtle.  The underlying cause has been the
need to initialize a stack for the new process.  The only portable way to
initialize a new stack is to set it as the alternate signal stack and take a
signal.  The signal handler does whatever initialization is needed and jumps
back to the original stack, where the fork processing is finished.  The basic
context switching mechanism is a jmp_buf for each process.  You switch to a
new process by longjmping to its jmp_buf.

Now that UML has its own implementation of setjmp and longjmp, and I can poke
around inside a jmp_buf without fear that libc will change the structure, a
much simpler mechanism is possible.  The jmpbuf can simply be initialized by
hand.

This eliminates -
	the need to set up and remove the alternate signal stack
	sending and handling a signal
	the signal blocking needed around the stack switching, since
there is no stack switching
	setting up the jmp_buf needed to jump back to the original
stack after the new one is set up

In addition, since jmp_buf is now defined by UML, and not by libc, it can be
embedded in the thread struct.  This makes it unnecessary to have it exist on
the stack, where it used to be.  It also simplifies interfaces, since the
switch jmp_buf used to be a void * inside the thread struct, and functions
which took it as an argument needed to define a jmp_buf variable and assign it
from the void *.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:16 -07:00
Jeff Dike 0915ee38c7 [PATCH] uml: mark some tt-mode code
Mark a symbol and file as being tt-mode only.  This shrinks the binary
slightly when tt mode support is compiled out and makes it easier to identity
stuff when tt mode is removed.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:16 -07:00
Jeff Dike a8b4fc4d7c [PATCH] uml: fix missing x86_64 register definitions
The UML/x86_64 headers were missing ptrace support for some segment registers.
 The underlying problem was that the x86_64 kernel uses user_regs_struct
rather than the ptrace register definitions in ptrace.  This patch switches
UML/x86_64 to using user_regs_struct for its definitions of the host's
registers.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:16 -07:00
Jeff Dike 5e7672ec3f [PATCH] uml: const more data
Make lots of structures const in order to make it obvious that they need no
locking.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:15 -07:00
Jeff Dike 75e29b18d9 [PATCH] uml: stack usage reduction
The KSTK_* macros used an inordinate amount of stack.  In order to overcome
an impedance mismatch between their interface, which just returns a single
register value, and the interface of get_thread_regs, which took a full
pt_regs, the implementation created an on-stack pt_regs, filled it in, and
returned one field.  do_task_stat calls KSTK_* twice, resulting in two
local pt_regs, blowing out the stack.

This patch changes the interface (and name) of get_thread_regs to just
return a single register from a jmp_buf.

The include of archsetjmp.h" in registers.h to get the definition of
jmp_buf exposed a bogus include of <setjmp.h> in start_up.c.  <setjmp.h>
shouldn't be used anywhere any more since UML uses the klibc
setjmp/longjmp.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:49:09 -07:00
Paolo 'Blaisorblade' Giarrusso bf61f50d63 [PATCH] uml: clean our set_ether_mac
Clean set_ether_mac usage.  Maybe could also be removed, but surely it can't
be a global function taking a void* argument.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Jeff Dike <jdike@addtoit.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:49:09 -07:00
Jeff Dike 602cc24181 [PATCH] uml: Remove unused variable
timer_irq_inited was useless, so it is removed.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:49:08 -07:00
Jeff Dike 537ae946e8 [PATCH] uml: timer cleanups
set_interval returns an error instead of panicing if setitimer fails.  Some of
its callers now check the return.

enable_timer is largely tt-mode-specific, so it is marked as such, and the
only skas-mode caller is made to call set-interval instead.

user_time_init was a no-value-added wrapper around set_interval, so it is
gone.

Since set_interval is now called from kernel code, callers no longer pass
ITIMER_* to it.  Instead, they pass a flag which is converted into ITIMER_REAL
or ITIMER_VIRTUAL.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:49:08 -07:00
Jeff Dike 4b84c69b5f [PATCH] uml: Move signal handlers to arch code
Have most signals go through an arch-provided handler which recovers the
sigcontext and then calls a generic handler.  This replaces the
ARCH_GET_SIGCONTEXT macro, which was somewhat fragile.  On x86_64, recovering
%rdx (which holds the sigcontext pointer) must be the first thing that
happens.  sig_handler duly invokes that first, but there is no guarantee that
I can see that instructions won't be reordered such that %rdx is used before
that.  Having the arch provide the handler seems much more robust.

Some signals in some parts of UML require their own handlers - these places
don't call set_handler any more.  They call sigaction or signal themselves.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:49:07 -07:00
Jeff Dike 19bdf0409f [PATCH] uml: SIGIO cleanups
- Various cleanups in the sigio code.

- Removed explicit zero-initializations of a few structures.

- Improved some error messages.

- An API change - there was an asymmetry between reactivate_fd calling
  maybe_sigio_broken, which goes through all the machinery of figuring out if
  a file descriptor supports SIGIO and applying the workaround to it if not,
  and deactivate_fd, which just turns off the descriptor.

  This is changed so that only activate_fd calls maybe_sigio_broken, when
  the descriptor is first seen.  reactivate_fd now calls add_sigio_fd, which
  is symmetric with ignore_sigio_fd.

  This removes a recursion which makes a critical section look more critical
  than it really was, obsoleting a big comment to that effect.  This requires
  keeping track of all descriptors which are getting the SIGIO treatment, not
  just the ones being polled at any given moment, so that reactivate_fd,
  through add_sigio_fd, doesn't try to tell the SIGIO thread about descriptors
  it doesn't care about.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:49:07 -07:00
Jeff Dike 13c06be399 [PATCH] uml: Use klibc setjmp/longjmp
This patch adds an implementation of setjmp and longjmp to UML, allowing
access to the inside of a jmpbuf without needing the access macros formerly
provided by libc.

The implementation is stolen from klibc.  I copy the relevant files into
arch/um.  I have another patch which avoids the copying, but requires klibc be
in the tree.

setjmp and longjmp users required some tweaking.  Includes of <setjmp.h> were
removed and includes of the UML longjmp.h were added where necessary.  There
are also replacements of siglongjmp with UML_LONGJMP which I somehow missed
earlier.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:49:05 -07:00
Jeff Dike 329c6e4257 [PATCH] uml: header formatting cleanups
Clean up whitespace and return syntax in os.h.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-14 21:53:52 -07:00
Jeff Dike a5df0d1a2c [PATCH] uml: tidy longjmp macro
The UML_SETJMP macro was requiring its users to pass in a argument which it
could supply itself, since it wasn't used outside that invocation of the
macro.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-14 21:53:52 -07:00
Jeff Dike 29ac1c2142 [PATCH] uml: make some symbols static
A few sigio-related things can be made static.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:24 -07:00
Jeff Dike 8e64d96aeb [PATCH] uml: remove os_isatty
os_isatty can be made to disappear by moving maybe_sigio_broken from kernel to
user code.  This also lets write_sigio_workaround become static.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:24 -07:00
Jeff Dike bfaafd7184 [PATCH] uml: remove spinlock wrapper functions
The irq_spinlock is not needed from user code any more, so the irq_lock and
irq_unlock wrappers can go away.  This also changes the name of the lock to
irq_lock.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:23 -07:00
Jeff Dike 8ae43ff8aa [PATCH] uml: mark forward_interrupts as being mode-specific
Mark forward_interrupts as being tt-mode only.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:23 -07:00
Jeff Dike bacf454918 [PATCH] uml: ifdef a mode-specific function
uml_idle_timer is tt-mode only, so ifdef it as such to make it easier to spot
when tt mode is killed.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:23 -07:00
Jeff Dike e64bd13408 [PATCH] uml: signal initialization cleanup
It turns out that init_new_thread_signals is always called with altstack == 1,
so we can eliminate the parameter.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:23 -07:00
Jeff Dike 23bbd586ed [PATCH] uml: fix static binary segfault
When UML is built as a static binary, it segfaults when run.  The reason is
that a memory hole that is present in dynamic binaries isn't there in static
binaries, and it contains essential stuff.

This fix removes the code which maps some anonymous memory into that hole and
cleans up some related code.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:23 -07:00
Jeff Dike aceb343464 [PATCH] uml: timer initialization cleanup
This cleans up the mess that is the timer initialization.  There used to be
two timer handlers - one that basically ran during delay loop calibration and
one that handled the timer afterwards.  There were also two sets of timer
initialization code - one that starts in user code and calls into the kernel
side of the house, and one that starts in kernel code and calls user code.

This eliminates one timer handler and consolidates the two sets of
initialization code.

[akpm@osdl.org: use new INTF_ flags]
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:23 -07:00
Tyler 598d188af1 [PATCH] uml: clean up address space limits code
I was looking at the code of the UML and more precisely at the functions
set_task_sizes_tt and set_task_sizes_skas.  I noticed that these 2 functions
take a paramater (arg) which is not used : the function is always called with
the value 0.

I suppose that this value might change in the future (or even can be
configured), so I added a constant in mem_user.h file.

Also, I rounded CONFIG_HOST_TASk_SIZE to a 4M.

Signed-off-by: Tyler <tyler@agat.net>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:23 -07:00
Jörn Engel 6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Greg Kroah-Hartman 264f48646e [PATCH] devfs: Remove the line_driver devfs_name field as it's no longer needed
Also fixes all drivers that set this field.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-26 12:25:09 -07:00
Adrian Bunk 17660bdd5c [PATCH] uml: remove dead declaration
Became irrelevant when x86_64 unexported ia32_sys_call_table.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Andi Kleen <ak@muc.de>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 10:00:58 -07:00
Jeff Dike 5cb38bc47b [PATCH] uml: fix wall_to_monotonic initialization
From: Jeff Dike <jdike@addtoit.com>

Initialize wall_to_monotonic correctly.  This fixes a problem where sleeps
lasted about one secone less than they should.  This also called for a bit of
code restructuring, following a patch which Blaisorblade had been keeping.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-05 12:29:17 -07:00
Jeff Dike ad28e02978 [PATCH] uml: change sigjmp_buf to jmp_buf
Clean up the jmpbuf code.  Since softints, we no longer use sig_setjmp, so
the UML_SIGSETJMP wrapper now has a misleading name.  Also, I forgot to
change the buffers from sigjmp_buf to jmp_buf.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-19 09:13:51 -07:00
Jeff Dike b73781c866 [PATCH] uml: MADV_REMOVE fixes
MADV_REMOVE fixes - change the test mapping to be MAP_SHARED instead of
MAP_PRIVATE, as MADV_REMOVE on MAP_PRIVATE maps won't work.  Also, use
the kernel's definition of MADV_REMOVE instead of hardcoding it if there
isn't a libc definition.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-19 09:13:49 -07:00
Paolo 'Blaisorblade' Giarrusso 5b0e94787f [PATCH] uml: fix "extern-vs-static" proto conflict in TLS code
Move the prototype from arch-generic to arch-specific includes because on
x86_64 these functions are two static inlines.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-11 06:18:36 -07:00
Paolo 'Blaisorblade' Giarrusso 9cf85b3af2 [PATCH] uml: request format warnings to GCC for appropriate functions
Add the format attribute to prototypes so GCC warns about improper usage.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-11 06:18:35 -07:00
Paolo 'Blaisorblade' Giarrusso 3feb88562d [PATCH] uml: check for differences in host support
If running on a host not supporting TLS (for instance 2.4) we should report
that cleanly to the user, instead of printing not comprehensible "error 5" for
that.

Additionally, i386 and x86_64 support different ranges for
user_desc->entry_number, and we must account for that; we couldn't pass
ourselves -1 because we need to override previously existing TLS descriptors
which glibc has possibly set, so test at startup the range to use.

x86 and x86_64 existing ranges are hardcoded.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:18:52 -08:00
Paolo 'Blaisorblade' Giarrusso dd77aec07a [PATCH] uml: tls support: hack to make it compile on any host
Copy the definition of struct user_desc (with another name) for use by
userspace sources (where we use the host headers, and we can't be sure about
their content) to make sure UML compiles.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:18:52 -08:00
Paolo 'Blaisorblade' Giarrusso aa6758d486 [PATCH] uml: implement {get,set}_thread_area for i386
Implement sys_[gs]et_thread_area and the corresponding ptrace operations for
UML.  This is the main chunk, additional parts follow.  This implementation is
now well tested and has run reliably for some time, and we've understood all
the previously existing problems.

Their implementation saves the new GDT content and then forwards the call to
the host when appropriate, i.e.  immediately when the target process is
running or on context switch otherwise (i.e.  on fork and on ptrace() calls).

In SKAS mode, we must switch registers on each context switch (because SKAS
does not switches tls_array together with current->mm).

Also, added get_cpu() locking; this has been done for SKAS mode, since TT does
not need it (it does not use smp_processor_id()).

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:18:52 -08:00
Paolo 'Blaisorblade' Giarrusso 972410b023 [PATCH] uml: clean arch_switch usage
Call arch_switch also in switch_to_skas, even if it's, for now, a no-op for
that case (and mark this in the comment); this will change soon.

Also, arch_switch for TT mode is actually useless when the PT proxy (a
complicate debugging instrumentation for TT mode) is not enabled.  In fact, it
only calls update_debugregs, which checks debugregs_seq against seq (to check
if the registers are up-to-date - seq here means a "version number" of the
registers).

If the ptrace proxy is not enabled, debugregs_seq always stays 0 and
update_debugregs will be a no-op.  So, optimize this out (the compiler can't
do it).

Also, I've been disappointed by the fact that it would make a lot of sense if,
after calling a successful
update_debugregs(current->thread.arch.debugregs_seq),
current->thread.arch.debugregs_seq were updated with the new debugregs_seq.
But this is not done.  Is this a bug or a feature?  For all purposes, it seems
a bug (otherwise the whole mechanism does not make sense, which is also a
possibility to check), which causes some performance only problems (not
correctness), since we write_debugregs when not needed.

Also, as suggested by Jeff, remove a redundant enabling of SIGVTALRM,
comprised in the subsequent local_irq_enable().  I'm just a bit dubious if
ordering matters there...

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:18:52 -08:00
Al Viro 4d338e1acc [PATCH] uml: sparse cleanups
misc sparse annotations

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:18:51 -08:00
Jeff Dike 9902abd7af [PATCH] uml: redeclare highmem
The earlier printf patch missed a corresponding change in the printed
variable.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:18:50 -08:00
Jeff Dike 02dea0875b [PATCH] UML: Hotplug memory, take 2
Changes since first version
	added check for MADV_REMOVE support on the host
	fixed error return botch
	shrunk sprintf array by one character

This adds hotplug memory support to UML.  The mconsole syntax is
 	config mem=[+-]n[KMG]
In other words, add or subtract some number of kilobytes, megabytes, or
gigabytes.

Unplugged pages are allocated and then madvise(MADV_TRUNCATE), which is a
currently experimental madvise extension.  These pages are tracked so they
can be plugged back in later if the admin decides to give them back.  The
first page to be unplugged is used to keep track of about 4M of other
pages.  A list_head is the first thing on this page.  The rest is filled
with addresses of other unplugged pages.  This first page is not madvised,
obviously.

When this page is filled, the next page is used in a similar way and linked
onto a list with the first page.  Etc.  This whole process reverses when
pages are plugged back in.  When a tracking page no longer tracks any
unplugged pages, then it is next in line for plugging, which is done by
freeing pages back to the kernel.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-31 12:18:50 -08:00
Jeff Dike cf9165a50a [PATCH] uml: oS header cleanups
This rearranges the OS declarations by moving some declarations into os.h.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:38 -08:00
Jeff Dike f206aabb03 [PATCH] uml: move sigio_user.c to os-Linux/sigio.c
The serial UML OS-abstraction layer patch (um/kernel dir).

This moves sigio_user.c to os-Linux dir

Signed-off-by: Gennady Sharapov <Gennady.V.Sharapov@intel.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:38 -08:00
Jeff Dike 8e367065ee [PATCH] uml: move SIGIO startup code to os-Linux/start_up.c
The serial UML OS-abstraction layer patch (um/kernel dir).

This moves all startup code from sigio_user.c file under os-Linux dir

Signed-off-by: Gennady Sharapov <Gennady.V.Sharapov@intel.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:38 -08:00
Jeff Dike 63ae2a94d9 [PATCH] uml: move libc-dependent irq code to os-Linux
The serial UML OS-abstraction layer patch (um/kernel dir).

This moves all systemcalls from irq_user.c file under os-Linux dir

Signed-off-by: Gennady Sharapov <Gennady.V.Sharapov@intel.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:37 -08:00
Jeff Dike c90e12b865 [PATCH] uml: fix declaration of exit()
This fixes a conflict between a header and what gcc "knows" the declaration'
to be.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:37 -08:00
Paolo 'Blaisorblade' Giarrusso 635dd50b7d [PATCH] uml: fix ((unused)) attribute
Use __attribute_used__ instead of __attribute__ ((unused)).  This will help
with GCC > 3.2.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-24 14:31:37 -08:00
Paolo 'Blaisorblade' Giarrusso 07f4e2c61c [PATCH] uml: fix usage of kernel_errno in place of errno
To avoid conflicts, in kernel files errno is expanded to kernel_errno, to
distinguish it from glibc errno.  In this case, the code wants to use the libc
errno but the kernel one is used; in the other usage, we return errno in place
of -errno in case of an error.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-24 14:31:37 -08:00
Jeff Dike e2216feb37 [PATCH] uml: initialize process FP registers properly
We weren't making sure that we initialized the FP registers of new processes
to sane values.

This patch also moves some defines in the affected area closer to where they
are used.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-07 16:12:32 -08:00
Paolo 'Blaisorblade' Giarrusso 72e5525765 [PATCH] uml: avoid "CONFIG_NR_CPUS undeclared" bogus error messages
Olaf Hering <olh@suse.de>

Olaf reported UML doesn't build for him with a clear analisys of what happened
- we're using NR_CPUS in files linked against glibc headers.  Seems like it
defines CONFIG_SMP but not CONFIG_NR_CPUS, so we get CONFIG_NR_CPUS
undeclared.

The fix is to move the declaration away from that header file and move it in
asm-um headers, and to add that header where needed.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:23 -08:00
Paolo 'Blaisorblade' Giarrusso b63162939c [PATCH] uml: avoid malloc to sleep in atomic sections
Ugly trick to help make malloc not sleeping - we can't do anything else.  But
this is not yet optimal, since spinlock don't trigger in_atomic() when
preemption is disabled.

Also, even if ugly, this was already used in one place, and was even more
bogus.  Fix it.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-18 19:20:21 -08:00
Jeff Dike c83d4635ee [PATCH] uml: use setjmp/longjmp instead of sigsetjmp/siglongjmp
Now that we are doing soft interrupts, there's no point in using sigsetjmp and
siglongjmp.  Using setjmp and longjmp saves a sigprocmask on every jump.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-18 19:20:20 -08:00
Jeff Dike 1d7173baf2 [PATCH] uml: implement soft interrupts
This patch implements soft interrupts.  Interrupt enabling and disabling no
longer map to sigprocmask.  Rather, a flag is set indicating whether
interrupts may be handled.  If a signal comes in and interrupts are marked as
OK, then it is handled normally.  If interrupts are marked as off, then the
signal handler simply returns after noting that a signal needs handling.  When
interrupts are enabled later on, this pending signals flag is checked, and the
IRQ handlers are called at that point.

The point of this is to reduce the cost of local_irq_save et al, since they
are very much more common than the signals that they are enabling and
disabling.  Soft interrupts produce a speed-up of ~25% on a kernel build.

Subtleties -

    UML uses sigsetjmp/siglongjmp to switch contexts.  sigsetjmp has been
    wrapped in a save_flags-like macro which remembers the interrupt state at
    setjmp time, and restores it when it is longjmp-ed back to.

    The enable_signals function has to loop because the IRQ handler
    disables interrupts before returning.  enable_signals has to return with
    signals enabled, and signals may come in between the disabling and the
    return to enable_signals.  So, it loops for as long as there are pending
    signals, ensuring that signals are enabled when it finally returns, and
    that there are no pending signals that need to be dealt with.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-18 19:20:20 -08:00
Gennady Sharapov abaf69773d [PATCH] uml: move libc-dependent skas process handling
The serial UML OS-abstraction layer patch (um/kernel/skas dir).

This moves all systemcalls from skas/process.c file under os-Linux dir and
join skas/process.c and skas/process_kern.c files.

Signed-off-by: Gennady Sharapov <gennady.v.sharapov@intel.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-18 19:20:19 -08:00
Gennady Sharapov f45d9fc9d8 [PATCH] uml: move libc-dependent skas memory mapping code
The serial UML OS-abstraction layer patch (um/kernel/skas dir).

This moves all systemcalls from skas/mem_user.c file under os-Linux dir and
join skas/mem_user.c and skas/mem.c files.

Signed-off-by: Gennady Sharapov <gennady.v.sharapov@intel.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-18 19:20:19 -08:00
Gennady Sharapov 4abfbf4034 [PATCH] uml: move headers to arch/um/include
The serial UML OS-abstraction layer patch (um/kernel dir).

This moves skas headers to arch/um/include.

Signed-off-by: Gennady Sharapov <Gennady.V.Sharapov@intel.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-18 19:20:19 -08:00
Gennady Sharapov cff65c4f0e [PATCH] uml: move libc-dependent time code
The serial UML OS-abstraction layer patch (um/kernel dir).

This moves all systemcalls from time.c file under os-Linux dir and joins
time.c and tine_kernel.c files

Signed-off-by: Gennady Sharapov <Gennady.V.Sharapov@intel.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-18 19:20:19 -08:00
Gennady Sharapov 4fef0c10fa [PATCH] uml: move libc-dependent utility procedures
The serial UML OS-abstraction layer patch (um/kernel dir).

This moves all systemcalls from user_util.c file under os-Linux dir

Signed-off-by: Gennady Sharapov <Gennady.V.Sharapov@intel.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-18 19:20:19 -08:00
Jesper Juhl 014c2544e6 return statement cleanup - kill pointless parentheses
This patch removes pointless parentheses from return statements.

Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-01-15 02:37:08 +01:00
Jeff Dike 4ee189a926 [PATCH] uml: fix missing KBUILD_BASENAME
2.6.15-mm1 caused kernel-offsets.c to stop compiling with a syntax error in a
header.  The problem was with KBUILD_BASENAME, which didn't get a definition
with the by-hand compilation in the main UML Makefile.

This was OK before since the expansion was syntactically the same as the
KBUILD_BASENAME token.  With -mm1, the expansion is now a quote-delimited
string, so there needs to be a definition of it.

Since kernel-offsets.c is basically the same as other arches' asm-offsets.c,
and those seem to build OK, this patch turns kernel-offsets.c into
asm-offsets.c.  kernel-offsets.c is in arch/um/sys-$(SUBARCH), i.e.  sys-i386
and sys-x86_64, while kbuild expects it to be in arch/um/kernel.
kernel-offsets.c is moved to
arch/um/include/sysdep-$(SUBARCH)/kernel-offsets.h, which is included by
arch/um/kernel/asm-offsets.c.  With that, include/asm-um/asm-offsets.h is
generated automatically.  kernel-offsets.h continues to exist because it needs
to be accessible to userspace UML code, and include/asm-um isn't.  So, a
symlink is made from arch/um/include/kernel-offsets.h to
include/asm-um/asm-offsets.h.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-11 18:42:09 -08:00
Gennady Sharapov ea2ba7dc3d [PATCH] uml: move libc-dependent code from trap_user.c
The serial UML OS-abstraction layer patch (um/kernel dir).

This moves all systemcalls from trap_user.c file under os-Linux dir

Signed-off-by: Gennady Sharapov <Gennady.V.Sharapov@intel.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:39 -08:00
Gennady Sharapov 0805d89c15 [PATCH] uml: move libc-dependent code from signal_user.c
The serial UML OS-abstraction layer patch (um/kernel dir).

This moves all systemcalls from signal_user.c file under os-Linux dir

Signed-off-by: Gennady Sharapov <Gennady.V.Sharapov@intel.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:39 -08:00
Jeff Dike 7b033e1fde [PATCH] uml: add mconsole_reply variant with length param
This is needed for the console output patch, since we have a possibly
non-NULL-terminated string there.  So, the new interface takes a string and a
length, and the old interface calls strlen on its string and calls the new
interface with the length.

There's also a bit of whitespace cleanup.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:47 -08:00
Jeff Dike 44700a4469 [PATCH] uml: better diagnostics for broken configs
Produce a compile-time error if both MODE_SKAS and MODE_TT are disabled.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:47 -08:00
Jeff Dike 7eebe8a9c5 [PATCH] uml: umid cleanup
This patch cleans up the umid code:

- The only_if_set argument to get_umid is gone.

- get_umid returns an empty string rather than NULL if there is no umid.

- umid_is_random is gone since its users went away.

- Some printfs were turned into printks because the code runs late enough
  that printk is working.

- Error paths were cleaned up.

- Some functions now return an error and let the caller print the error
  message rather than printing it themselves.  This eliminates the practice of
  passing a pointer to printf or printk in, depending on where in the boot
  process we are.

- Major tidying of not_dead_yet - mostly error path cleanup, plus a comment
  explaining why it doesn't react to errors the way you might expect.

- Calls to os_* interfaces that were moved under os are changed back to
  their native libc forms.

- snprintf, strlcpy, and their bounds-checking friends are used more often,
  replacing by-hand bounds checking in some places.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:47 -08:00
Jeff Dike 2264c475e4 [PATCH] uml: separate libc-dependent umid code
I reworked Gennady's umid OS abstraction patch because the code shouldn't
be moved entirely to os.  As it turns out, I moved most of it anyway.  This
patch is the minimal one needed to move the code and have it work.
It turns out that the concept of the umid is OS-independent, but
almost everything else about the implementation is OS-dependent.

This is code movement without cleanup - a follow-on patch tidies
everything up without shuffling code around.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:47 -08:00
Jeff Dike e4dcee8099 [PATCH] uml: Add throttling to console driver
This patch adds support for throttling and unthrottling input when the tty
driver can't handle it.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:46 -08:00
Jeff Dike 165dc59116 [PATCH] uml: Simplify console opening/closing and irq registration
This patch simplifies the opening and closing of host console devices and the
registration and deregistration of IRQs.  The intent is to make it obvious
that an IRQ can't exist without an open file descriptor.

chan_enable will now open the channel, and when both opening and IRQ
registration are desired, this should be used.  Opening only is done for the
initial console, so that interface still needs to exist.

The free_irqs_later interface is now gone.  It was intended to avoid freeing
an IRQ while it was being processed.  It did this, but it didn't eliminate the
possiblity of free_irq being called from an interrupt, which is bad.  In its
place is a list of irqs to be freed, which is processed by the signal handler
just before exiting.  close_one_chan now disables irqs.

When a host device disappears, it is just closed, and that disables IRQs.

The device id registered with the IRQ is now the chan structure, not the tty.
This is because the interrupt arrives on a descriptor associated with the
channel.  This caused equivalent changes in the arguments to line_timer_cb.
line_disable is gone since it is not used any more.

The count field in the line structure is gone.  tty->count is used instead.

The complicated logic in sigio_handler with freeing IRQs when necessary and
making sure its idea of the next irq is correct is now much simpler.  The irq
list can't be rearranged underneath it, so it is now a simple list walk.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:46 -08:00
Jeff Dike 1f80171e81 [PATCH] uml: move console configuration
This patch changes when console devices are configured in order to prepare the
ground for the next patch.

parse_chan_pair is now done earlier, when initcalls are run, rather than when
the device is opened.

When a host device disappears, the channel list is closed, but not freed.
This is required by the previous change.  line_config now takes the options
structure as an argument, and line_open doesn't.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:46 -08:00
Jeff Dike 9010772cdf [PATCH] uml: Add static initializations and declarations
Some structure fields were being dynamically initialized when they could be
initialized at compile-time instead.  This also makes some declarations static
(in the C sense).

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:46 -08:00
Jeff Dike d571cd18f2 [PATCH] uml: Move mconsole support out of generic code
A bit of restructuring which eliminates the all_allowed argument (which is
mconsole-specific) to line_setup.  That logic is moved to the mconsole
callback.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:45 -08:00
Jeff Dike 88890b8874 [PATCH] uml: Remove unneeded structure field
This removes a structure field which turned out to be pointless, and
references to it.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:45 -08:00
Jeff Dike d50084a299 [PATCH] uml: Formatting changes
This patch makes a bunch of non-functional changes -
    return(foo); becomes return foo;
    some statements are broken across lines for readability
    some trailing whitespace is cleaned up
    open_one_chan took four arguments, three of which could be
       deduced from the first.  Accordingly, they were eliminated.
    some examples of "} else {" had a newline added
    some whitespace cleanup in the indentation
    lines_init got some control flow cleanup
    some long lines were broken
    removed another emacs-specific C formatting comment

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:45 -08:00
Jeff Dike 5b7b15afee [PATCH] uml skas0: stop gcc's insanity
With Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>

UML skas0 stub has been miscompiling for many people (incidentally not
the authors), depending on the used GCC versions.

I think (and testing on some GCC versions shows) this patch avoids the
fundamental issue which is behind this, namely gcc using the stack when
we have just replaced it, behind gcc's back.  The remapping and storage
of the return value is hidden in a blob of asm, hopefully giving gcc no
room for creativity.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-18 11:19:44 -08:00
Pekka J Enberg bf001b2679 [PATCH] uml: fix compile error for tt
arch/um/kernel/tt/uaccess.c: In function `copy_from_user_tt':
arch/um/kernel/tt/uaccess.c:11: error: `FIXADDR_USER_START' undeclared (first use in this function)
arch/um/kernel/tt/uaccess.c:11: error: (Each undeclared identifier is reported only once
arch/um/kernel/tt/uaccess.c:11: error: for each function it appears in.)

I get the compile error when I disable CONFIG_MODE_SKAS.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Paolo Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-12-12 08:57:43 -08:00
Jeff Dike 17d469715c [PATCH] uml: properly invoke x86_64 system calls
This patch makes stub_segv use the stub_syscall macros.  This was needed
anyway, but the bug that prompted this was the discovery that gcc was storing
stuff in RCX, which is trashed across a system call.  This is exactly the sort
of problem that the new macros fix.

There is a stub_syscall0 for getpid.  stub_segv was changed to be a libc file,
and that caused some include changes.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-22 09:13:41 -08:00
Paolo 'Blaisorblade' Giarrusso 7a590611c0 [PATCH] uml: fix access_ok
The access_ok_tt() macro is bogus, in that a read access is unconditionally
considered valid.

I couldn't find in SCM logs the introduction of this check, but I went back to
2.4.20-1um and the definition was the same.

Possibly this was done to avoid problems with missing set_fs() calls, but
there can't be any I think because they would fail with SKAS mode.
TT-specific code is still to check.

Also, this patch joins common code together, and makes the "address range
wrapping" check happen for all cases, rather than for only some.

This may, possibly, be reoptimized at some time, but the current code doesn't
seem clever, just confused.

* Important: I've also had to change references to access_ok_{tt,skas} back to
  access_ok - the kernel wasn't that happy otherwise.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-13 18:14:15 -08:00
Paolo 'Blaisorblade' Giarrusso 55c033c1f6 [PATCH] uml console channels: fix the API of console_write
Since the 4th param is unused, remove it altogether.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-13 18:14:14 -08:00
Jeff Dike ae17381608 [PATCH] uml: big memory fixes
A number of fixes to improve behavior when large physical memory sizes
are specified:

- libc files need -D_FILE_OFFSET_BITS=64 because there are unavoidable uses
  of non-64 interfaces in libc

- some %d need to be %u

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:53:31 -08:00
Jeff Dike ff5c6ff542 [PATCH] uml: separate libc-dependent helper code
The serial UML OS-abstraction layer patch (um/kernel dir).

This moves all systemcalls from helper.c file under os-Linux dir

Signed-off-by: Gennady Sharapov <Gennady.V.Sharapov@intel.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:53:31 -08:00
Gennady Sharapov bb57842625 [PATCH] uml: separate libc-dependent uaccess code
The serial UML OS-abstraction layer patch (um/kernel dir).

This moves all systemcalls from uaccess_user.c file under os-Linux dir

Signed-off-by: Gennady Sharapov <Gennady.V.Sharapov@intel.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:53:31 -08:00
Bodo Stroesser 0e76422ca5 [PATCH] uml: fix UML network driver endianness bugs
ifa->ifa_address and ifa->ifa_mask are defined as __u32, but used as if they
were char[4].

Network code uses htons() to convert it.  So UML's method to access these
fields is wrong for bigendians (e.g.  s390)

I replaced bytewise copying by memcpy(), maybe even that might be removed, if
ifa->ifa_address/mask may be used immediately.

Signed-off-by: Bodo Stroesser <bstroesser@fujitsu-siemens.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Cc: <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:53:30 -08:00
Paolo 'Blaisorblade' Giarrusso 4f0272415a [PATCH] uml: fix syscall stubs
Jeff Dike noted that the assembly code for syscall stubs is misassembled with
GCC 3.2.3: the values copied in registers weren't preserved between one asm()
and the following one.

So I fixed the thing by rewriting the __asm__ constraints more like unistd.h
ones.

Note: in syscall6 case I had to add one more instruction (i.e.  moving arg6 in
eax and shuffling things around) - it's needed for the function to be valid in
general (we can't load the value from the stack, relative to ebp, because we
change it), but could be avoided since we actually use a constant as param 6.

The only fix would be to turn stub_syscall6 to a macro and use a "i"
constraint for arg6 (i.e., specify it's a constant value).

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:53:30 -08:00
Al Viro bbc5b21284 [PATCH] missing platform_device.h includes
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-01 21:50:01 -08:00
Christoph Hellwig dfb7dac3af [PATCH] unify sys_ptrace prototype
Make sure we always return, as all syscalls should.  Also move the common
prototype to <linux/syscalls.h>

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 17:37:20 -08:00
Hugh Dickins b38c6845b6 [PATCH] mm: uml kill unused
In worrying over the various pte operations in different architectures, I came
across some unused functions in UML: remove mprotect_kernel_vm,
protect_vm_page and addr_pte.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-29 21:40:42 -07:00
Miklos Szeredi 10ded9493e [PATCH] uml: fix compile failure for TT mode
Without this patch, uml compile fails with:

  LD      .tmp_vmlinux1
arch/um/kernel/built-in.o: In function `config_gdb_cb':
arch/um/kernel/tt/gdb.c:129: undefined reference to `TASK_EXTERN_PID'

Tested on i386, but fix needed on x86_64 too AFAICS.

Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-24 08:59:25 -07:00
Al Viro 450da6ca97 [PATCH] build fix for uml/amd64
Missing half of the [PATCH] uml: Fix sysrq-r support for skas mode
We need to remove these (UPT_[DEFG]S) from the read side as well as the
write one - otherwise it simply won't build.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-19 23:18:16 -07:00
Paolo 'Blaisorblade' Giarrusso 9d624ea474 [PATCH] uml: compile-time fix recent patch
Give an empty definition for clear_can_do_skas() when it is not needed.
Thanks to Junichi Uekawa <dancer@netfort.gr.jp> for reporting the
breakage and providing a fix (I re-fixed it in an IMHO cleaner way).

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-12 08:22:26 -07:00
Jeff Dike 91acb21f08 [PATCH] uml: revert block driver use of host AIO
The patch to use host AIO support that I submitted early after 2.6.13 exposed
some problems in the block driver.  I have fixes for these, but am not
comfortable putting them into 2.6.14 at this late date.  So, this patch reverts
the use of host AIO.

I will resubmit the original patch, plus fixes to the driver after 2.6.14
in order to get a reasonable amount of testing before they're exposed to
the general public.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-12 08:22:26 -07:00
Allan Graves fad1c45c93 [PATCH] uml: Fix sysrq-r support for skas mode
The old code had the IP and SP coming from the registers in the thread
struct, which are completely wrong since those are the userspace
registers.  This fixes that by pulling the correct values from the
jmp_buf in which the kernel state of each thread is stored.

Signed-off-by: Allan Graves <allan.graves@oracle.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-04 13:22:01 -07:00
Paolo 'Blaisorblade' Giarrusso 8923648c12 [PATCH] uml: clear SKAS0/3 flags when running in TT mode
SEGV_MAYBE_FIXABLE tests ptrace_faultinfo, and depends on it being 1 only in
SKAS3 mode, while currently when running with mode=tt it will be 1 anyway.
Fix this, and do the same for proc_mm.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-30 12:41:18 -07:00
Paolo 'Blaisorblade' Giarrusso be662a18b7 [PATCH] uml: fix page faults in SKAS3 mode.
I hadn't been running a SKAS3 host when testing the "uml: fix hang in TT mode
on fault" patch (commit 546fe1cbf9), and I
didn't think enough to the missing trap_no in SKAS3 mode.

In fact, the resulting kernel doesn't work at all in SKAS3 mode.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-30 12:41:18 -07:00
Al Viro ecba97d4aa [PATCH] uml makefiles sanitized
UML makefiles sanitized:
 - number of generated headers reduced to 2 (from user-offsets.c and
   kernel-offsets.c resp.).  The rest is made constant and simply
   includes those two.
 - mk_... helpers are gone now that we don't need to generate these
   headers
 - arch/um/include2 removed since everything under arch/um/include/sysdep
   is constant now and symlink can point straight to source tree.
 - dependencies seriously simplified.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-29 08:46:26 -07:00
Paolo 'Blaisorblade' Giarrusso a8bfb94c58 [PATCH] strlcat: use for uml umid.c
Simplify the code by using strlcat() instead of strncat() and manual
appending.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-22 22:17:36 -07:00
Paolo 'Blaisorblade' Giarrusso 41c79dc382 [PATCH] uml: fix bogus HOST_ELF_CLASS symbol name
Even if with a bit of misunderstanding, Al fixed this in commit
95608261da.

Well, the symbol was intended to come from userspace (it exists there on normal
host), but since some hosts may miss that, using the kernel one is just as fine.
However, rename it to be named consistently with the rest.

Actually, he missed converting ELFCLASS32 to coming from kernel headers. For
consistence, add ELFCLASS64 too.

Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-21 16:16:30 -07:00
Jeff Dike 0f80bc85c5 [PATCH] uml: move libc code out of mem_user.c and tempfile.c
The serial UML OS-abstraction layer patch (um/kernel dir).

This moves all system calls from mem_user.c and tempfile.c files under
os-Linux dir.

Signed-off-by: Gennady Sharapov <Gennady.V.Sharapov@intel.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-17 11:50:00 -07:00
Jeff Dike 3eddddcf23 [PATCH] uml: breakpoint an arbitrary thread
This patch implements a stack trace for a thread, not unlike sysrq-t does.
The advantage to this is that a break point can be placed on showreqs, so that
upon showing the stack, you jump immediately into the debugger.  While sysrq-t
does the same thing, sysrq-t shows *all* threads stacks.  It also doesn't work
right now.  In the future, I thought it might be acceptable to make this show
all pids stacks, but perhaps leaving well enough alone and just using sysrq-t
would be okay.  For now, upon receiving the stack command, UML switches
context to that thread, dumps its registers, and then switches context back to
the original thread.  Since UML compacts all threads into one of 4 host
threads, this sort of mechanism could be expanded in the future to include
other debugging helpers that sysrq does not cover.

Note by jdike - The main benefit to this is that it brings an arbitrary thread
back into context, where it can be examined by gdb.  The fact that it dumps it
stack is secondary.  This provides the capability to examine a sleeping
thread, which has existed in tt mode, but not in skas mode until now.

Also, the other threads, that sysrq doesn't cover, can be gdb-ed directly
anyway.

Signed-off-by: Allan Graves<allan.graves@gmail.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-17 11:49:59 -07:00
Paolo 'Blaisorblade' Giarrusso d99c4022f6 [PATCH] uml: inline mk_pte and various friends
Turns out that, for UML, a *lot* of VM-related trivial functions are not
inlined but rather normal functions.

In other sections of UML code, this is justified by having files which
interact with the host and cannot therefore include kernel headers, but in
this case there's no such justification.

I've had to turn many of them to macros because of missing declarations. While
doing this, I've decided to reuse some already existing macros.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-10 12:00:18 -07:00
viro@ZenIV.linux.org.uk 95608261da [PATCH] bogus symbol used in arch/um/os-Linux/elf_aux.c
elf_aux is userland code; it uses symbol (ELF_CLASS) that doesn't exist in
userland headers; pulled into kernel-offsets.h, switched elf_aux to using it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 17:17:33 -07:00
Jesper Juhl 97de50c0ad [PATCH] remove verify_area(): remove verify_area() from various uaccess.h headers
Remove the deprecated (and unused) verify_area() from various uaccess.h
headers.

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:35 -07:00
Bodo Stroesser 07bf731e4b [PATCH] uml: skas0 stubs now check system call return values
Change syscall-stub's data to include a "expected retval".

Stub now checks syscalls retval and aborts execution of syscall list, if
retval != expected retval.

run_syscall_stub prints the data of the failed syscall, using the data pointer
and retval written by the stub to the beginning of the stack.

one_syscall_stub is removed, to simplify code, because only some instructions
are saved by one_syscall_stub, no host-syscall.

Using the stub with additional data (modify_ldt via stub)
is prepared also.

Signed-off-by: Bodo Stroesser <bstroesser@fujitsu-siemens.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:24 -07:00
Gennady Sharapov 60d339f6fe [PATCH] uml: move libc-dependent startup and signal code
The serial UML OS-abstraction layer patch (um/kernel dir).

This moves all systemcalls from process.c file under os-Linux dir and join
process.c and process_kern.c files.

Signed-off-by: Gennady Sharapov <gennady.v.sharapov@intel.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:24 -07:00
Jeff Dike 09ace81c1d [PATCH] uml: add host AIO support to block driver
This adds AIO support to the ubd driver.

The driver breaks a struct request into IO requests to the host, based on the
hardware segments in the request and on any COW blocks covered by the request.

The ubd IO thread is gone, since there is now an equivalent thread in the AIO
module.

There is provision for multiple outstanding requests now.  Requests aren't
retired until all pieces of it have been completed.  The AIO requests have a
shared count, which is decremented as IO operations come in until it reaches
0.  This can be possibly moved to the request struct - haven't looked at this
yet.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:23 -07:00
Jeff Dike 75e5584c89 [PATCH] uml: use host AIO support
This patch makes UML use host AIO support when it (and
/usr/include/linux/aio_abi.h) are present.  This is only the support, with no
consumers - a consumer is coming in the next patch.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:23 -07:00
Jeff Dike e32dacb9f4 [PATCH] uml: system call path cleanup
This merges two sets of files which had no business being split apart in the
first place.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:23 -07:00
Jeff Dike c56004901f [PATCH] uml: TLB operation batching
This adds VM op batching to skas0.  Rather than having a context switch to and
from the userspace stub for each address space change, we write a number of
operations to the stub data page and invoke a different stub which loops over
them and executes them all in one go.

The operations are stored as [ system call number, arg1, arg2, ... ] tuples.

The set is terminated by a system call number of 0.  Single operations, i.e.
page faults, are handled in the old way, since that is slightly more
efficient.

For a kernel build, a minority (~1/4) of the operations are part of a set.
These sets averaged ~100 in length, so for this quarter, the context switching
overhead is greatly reduced.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:22 -07:00
Al Viro 7efd08c855 [PATCH] uml: fix a macro typo
Fix a macro typo which could break if the macro is passed arguments with
side-effects.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:06:21 -07:00
Bodo Stroesser 9786a8f3cb [PATCH] uml: Proper clone support for skas0
This patch implements the clone-stub mechanism, which allows skas0 to run
with proc_mm==0, even if the clib in UML uses modify_ldt.

Note: There is a bug in skas3.v7 host patch, that avoids UML-skas from
running properly on a SMP-box.  In full skas3, I never really saw problems,
but in skas0 they showed up.

More commentary by jdike - What this patch does is makes sure that the host
parent of each new host process matches the UML parent of the corresponding
UML process.  This ensures that any changed LDTs are inherited.  This is
done by having clone actually called by the UML process from its stub,
rather than by the kernel.  We have special syscall stubs that are loaded
onto the stub code page because that code must be completely
self-contained.  These stubs are given C interfaces, and used like normal C
functions, but there are subtleties.  Principally, we have to be careful
about stack variables in stub_clone_handler after the clone.  The code is
written so that there aren't any - everything boils down to a fixed
address.  If there were any locals, references to them after the clone
would be wrong because the stack just changed.

Signed-off-by: Bodo Stroesser <bstroesser@fujitsu-siemens.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-07 18:23:44 -07:00
Jeff Dike d67b569f5f [PATCH] uml: skas0 - separate kernel address space on stock hosts
UML has had two modes of operation - an insecure, slow mode (tt mode) in
which the kernel is mapped into every process address space which requires
no host kernel modifications, and a secure, faster mode (skas mode) in
which the UML kernel is in a separate host address space, which requires a
patch to the host kernel.

This patch implements something very close to skas mode for hosts which
don't support skas - I'm calling this skas0.  It provides the security of
the skas host patch, and some of the performance gains.

The two main things that are provided by the skas patch, /proc/mm and
PTRACE_FAULTINFO, are implemented in a way that require no host patch.

For the remote address space changing stuff (mmap, munmap, and mprotect),
we set aside two pages in the process above its stack, one of which
contains a little bit of code which can call mmap et al.

To update the address space, the system call information (system call
number and arguments) are written to the stub page above the code.  The
%esp is set to the beginning of the data, the %eip is set the the start of
the stub, and it repeatedly pops the information into its registers and
makes the system call until it sees a system call number of zero.  This is
to amortize the cost of the context switch across multiple address space
updates.

When the updates are done, it SIGSTOPs itself, and the kernel process
continues what it was doing.

For a PTRACE_FAULTINFO replacement, we set up a SIGSEGV handler in the
child, and let it handle segfaults rather than nullifying them.  The
handler is in the same page as the mmap stub.  The second page is used as
the stack.  The handler reads cr2 and err from the sigcontext, sticks them
at the base of the stack in a faultinfo struct, and SIGSTOPs itself.  The
kernel then reads the faultinfo and handles the fault.

A complication on x86_64 is that this involves resetting the registers to
the segfault values when the process is inside the kill system call.  This
breaks on x86_64 because %rcx will contain %rip because you tell SYSRET
where to return to by putting the value in %rcx.  So, this corrupts $rcx on
return from the segfault.  To work around this, I added an
arch_finish_segv, which on x86 does nothing, but which on x86_64 ptraces
the child back through the sigreturn.  This causes %rcx to be restored by
sigreturn and avoids the corruption.  Ultimately, I think I will replace
this with the trick of having it send itself a blocked signal which will be
unblocked by the sigreturn.  This will allow it to be stopped just after
the sigreturn, and PTRACE_SYSCALLed without all the back-and-forth of
PTRACE_SYSCALLing it through sigreturn.

This runs on a stock host, so theoretically (and hopefully), tt mode isn't
needed any more.  We need to make sure that this is better in every way
than tt mode, though.  I'm concerned about the speed of address space
updates and page fault handling, since they involve extra round-trips to
the child.  We can amortize the round-trip cost for large address space
updates by writing all of the operations to the data page and having the
child execute them all at the same time.  This will help fork and exec, but
not page faults, since they involve only one page.

I can't think of any way to help page faults, except to add something like
PTRACE_FAULTINFO to the host.  There is PTRACE_SIGINFO, but UML doesn't use
siginfo for SIGSEGV (or anything else) because there isn't enough
information in the siginfo struct to handle page faults (the faulting
operation type is missing).  Adding that would make PTRACE_SIGINFO a usable
equivalent to PTRACE_FAULTINFO.

As for the code itself:

- The system call stub is in arch/um/kernel/sys-$(SUBARCH)/stub.S.  It is
  put in its own section of the binary along with stub_segv_handler in
  arch/um/kernel/skas/process.c.  This is manipulated with run_syscall_stub
  in arch/um/kernel/skas/mem_user.c.  syscall_stub will execute any system
  call at all, but it's only used for mmap, munmap, and mprotect.

- The x86_64 stub calls sigreturn by hand rather than allowing the normal
  sigreturn to happen, because the normal sigreturn is a SA_RESTORER in
  UML's address space provided by libc.  Needless to say, this is not
  available in the child's address space.  Also, it does a couple of odd
  pops before that which restore the stack to the state it was in at the
  time the signal handler was called.

- There is a new field in the arch mmu_context, which is now a union.
  This is the pid to be manipulated rather than the /proc/mm file
  descriptor.  Code which deals with this now checks proc_mm to see whether
  it should use the usual skas code or the new code.

- userspace_tramp is now used to create a new host process for every UML
  process, rather than one per UML processor.  It checks proc_mm and
  ptrace_faultinfo to decide whether to map in the pages above its stack.

- start_userspace now makes CLONE_VM conditional on proc_mm since we need
  separate address spaces now.

- switch_mm_skas now just sets userspace_pid[0] to the new pid rather
  than PTRACE_SWITCH_MM.  There is an addition to userspace which updates
  its idea of the pid being manipulated each time around the loop.  This is
  important on exec, when the pid will change underneath userspace().

- The stub page has a pte, but it can't be mapped in using tlb_flush
  because it is part of tlb_flush.  This is why it's required for it to be
  mapped in by userspace_tramp.

Other random things:

- The stub section in uml.lds.S is page aligned.  This page is written
  out to the backing vm file in setup_physmem because it is mapped from
  there into user processes.

- There's some confusion with TASK_SIZE now that there are a couple of
  extra pages that the process can't use.  TASK_SIZE is considered by the
  elf code to be the usable process memory, which is reasonable, so it is
  decreased by two pages.  This confuses the definition of
  USER_PGDS_IN_LAST_PML4, making it too small because of the rounding down
  of the uneven division.  So we round it to the nearest PGDIR_SIZE rather
  than the lower one.

- I added a missing PT_SYSCALL_ARG6_OFFSET macro.

- um_mmu.h was made into a userspace-usable file.

- proc_mm and ptrace_faultinfo are globals which say whether the host
  supports these features.

- There is a bad interaction between the mm.nr_ptes check at the end of
  exit_mmap, stack randomization, and skas0.  exit_mmap will stop freeing
  pages at the PGDIR_SIZE boundary after the last vma.  If the stack isn't
  on the last page table page, the last pte page won't be freed, as it
  should be since the stub ptes are there, and exit_mmap will BUG because
  there is an unfreed page.  To get around this, TASK_SIZE is set to the
  next lowest PGDIR_SIZE boundary and mm->nr_ptes is decremented after the
  calls to init_stub_pte.  This ensures that we know the process stack (and
  all other process mappings) will be below the top page table page, and
  thus we know that mm->nr_ptes will be one too many, and can be
  decremented.

Things that need fixing:

- We may need better assurrences that the stub code is PIC.

- The stub pte is set up in init_new_context_skas.

- alloc_pgdir is probably the right place.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-07 18:23:44 -07:00
Jeff Dike 29d56cfe3c [PATCH] uml: hot-unplug code cleanup
Clean up the hot-unplugging code.  There is now an id procedure which is
called to figure out what device we're talking to.  The error messages from
that are now done from mconsole_remove instead of the driver.  remove is now
called with the device number, after it has been checked, so doesn't need to
do sanity checking on it.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25 16:24:36 -07:00
Jeff Dike fc47a0d18a [PATCH] uml: time initialization tidying
user_time_init_skas and user_time_init_tt were essentially the same.  So, this
merges them, deleting the mode-specific functions and declarations.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25 16:24:35 -07:00
Jeff Dike 36ca1195ad [PATCH] uml: build cleanups
Fix a build failure when CONFIG_MODE_SKAS is disabled and make a Makefile
comment fit in 80 columns.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-13 20:58:43 -07:00
Jeff Dike da00d9a546 [PATCH] uml: compile fixes for gcc 4
This is a bunch of compile fixes provoked by building UML with gcc 4.  There
are a bunch of signedness mismatches, a couple of uninitialized references,
and a botched C99 structure initialization which had somehow gone unnoticed.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-08 16:21:12 -07:00
Paolo 'Blaisorblade' Giarrusso b3461034d7 [PATCH] uml: stack dump fix
Copy (and adapt) to UML the stack code dumper used in i386 when
CONFIG_FRAME_POINTER is enabled.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-28 16:46:13 -07:00
Jeff Dike a2e4b972c9 [PATCH] uml: remove 2_5compat.h
Remove old useless header that was used in Ye Olde Times during 2.4->2.5
porting to abstract differences.  It's definitions are no more used anyway, so
let's finally kill it.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-28 16:46:11 -07:00
Jeff Dike ba9950c820 [PATCH] uml: small fixes left over from rc4
Some changes that I sent in didn't make 2.6.12-rc4 for some reason.  This
adds them back.  We have
	an x86_64 definition of TOP_ADDR
	a reimplementation of the x86_64 csum_partial_copy_from_user
	some syntax fixes in arch/um/kernel/ptrace.c
	removal of a CFLAGS definition in the x86_64 Makefile
	some include changes in the x86_64 ptrace.c and user-offsets.h
	a syntax fix in elf-x86_64.h
Also moved an include in the i386 and x86_64 Makefiles to make the symlinks
work, and some small fixes from Al Viro.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-20 15:48:17 -07:00
Jeff Dike 16c1116301 [PATCH] uml: command line handling cleanup
Command line handling cleanups - a couple of things made static and an
unused declaration removed from header.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-06 22:09:29 -07:00
Bodo Stroesser 3a0a64e6c9 [PATCH] uml: header and code cleanup
Remove some definitions and declarations from arch/um/include/skas_ptrace.h,
as they have moved to arch/um/include/sysdep/skas_ptrace.h

Also, remove PTRACE_SIGPENDING support in UML at all.

Signed-off-by: Bodo Stroesser <bstroesser@fujitsu-siemens.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-05 16:36:39 -07:00
Bodo Stroesser 51a6b0c59a [PATCH] uml: s390 preparation, sighandler interface abstraction
s390 passes parameters in registers.  So the only safe way to find out the
address of signal context, error-address and error-type (trap_no), which are
passed to signal handlers as parameters, is to declare these parameters.

So I inserted an subarch-specific macro which holds the declaration of
parameters for signal handlers.

Signed-off-by: Bodo Stroesser <bstroesser@fujitsu-siemens.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-05 16:36:38 -07:00
Bodo Stroesser 7d37c6d52f [PATCH] uml: s390 preparation, checksumming done in arch code
Checksum handling largely depends on the subarch.

Thus, I renamed i386 arch_csum_partial in arch/um/sys-i386/checksum.S back to
csum_partial, removed csum_partial from arch/um/kernel/checksum.c and shifted
EXPORT_SYMBOL(csum_partial) to arch/um/sys-i386/ksyms.c.

Then, csum_partial_copy_to and csum_partial_copy_from were shifted from
arch/um/kernel/checksum.c to arch/um/include/sysdep-i386/checksum.h and
inserted in the calling functions csum_partial_copy_from_user() and
csum_and_copy_to_user().

Now, arch/um/kernel/checksum.c is empty and removed.

Signed-off-by: Bodo Stroesser <bstroesser@fujitsu-siemens.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-05 16:36:38 -07:00
Jeff Dike cd2ee4a30c [PATCH] uml: Fix SIGWINCH relaying
This makes SIGWINCH work again, and fixes a couple of SIGWINCH-associated
crashes.  First, the sigio thread disables SIGWINCH because all hell breaks
loose if it ever gets one and tries to call the signal handling code.  Second,
there was a problem with deferencing tty structs after they were freed.  The
SIGWINCH support for a tty wasn't being turned off or freed after the tty went
away.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-05 16:36:36 -07:00
Bodo Stroesser c578455a3e [PATCH] uml: S390 preparation, abstract host page fault data
This patch removes the arch-specific fault/trap-infos from thread and
skas-regs.

It adds a new struct faultinfo, that is arch-specific defined in
sysdep/faultinfo.h.

The structure is inserted in thread.arch and thread.regs.skas and
thread.regs.tt

Now, segv and other trap-handlers can copy the contents from regs.X.faultinfo
to thread.arch.faultinfo with one simple assignment.

Also, the number of macros necessary is reduced to

FAULT_ADDRESS(struct faultinfo)
    extracts the faulting address from faultinfo

FAULT_WRITE(struct faultinfo)
    extracts the "is_write" flag

SEGV_IS_FIXABLE(struct faultinfo)
    is true for the fixable segvs, i.e. (TRAP == 14)
    on i386

UPT_FAULTINFO(regs)
    result is (struct faultinfo *) to the faultinfo
    in regs->skas.faultinfo

GET_FAULTINFO_FROM_SC(struct faultinfo, struct sigcontext *)
    copies the relevant parts of the sigcontext to
    struct faultinfo.

On SIGSEGV, call user_signal() instead of handle_segv(), if the architecture
provides the information needed in PTRACE_FAULTINFO, or if PTRACE_FAULTINFO is
missing, because segv-stub will provide the info.

The benefit of the change is, that in case of a non-fixable SIGSEGV, we can
give user processes a SIGSEGV, instead of possibly looping on pagefault
handling.

Since handle_segv() sikked arch_fixup() implicitly by passing ip==0 to segv(),
I changed segv() to call arch_fixup() only, if !is_user.

Signed-off-by: Bodo Stroesser <bstroesser@fujitsu-siemens.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-05 16:36:36 -07:00
Al Viro a31769ed3e [PATCH] uml: cross-build support : kernel_offsets
The next group of helpers is a bit trickier - they want the constants similar
to those in user-offsets.h, but we need target sc.h for it.  So we can't put
that into user-offsets (sc.h depends on it) and need the second generated
header for that stuff (kernel-offsets.h.  BFD...

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-05 16:36:35 -07:00
Stephen Rothwell 7d87e14c23 [PATCH] consolidate sys_shmat
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01 08:59:12 -07:00
Paolo 'Blaisorblade' Giarrusso b97b77cca6 [PATCH] uml: redo console locking
Fix some console locking problems (including scheduling in atomic) and various
reorderings and cleanup in that code.  Not yet ready for 2.6.12 probably.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01 08:58:56 -07:00
Paolo 'Blaisorblade' Giarrusso 80f9507886 [PATCH] uml: fix syscall table by including $(SUBARCH)'s one, for x86-64
Reuse asm-x86-64/unistd.h to build our syscall table, like x86-64 already
does.

Like for i386, we must add some #defines for all the (right!) changes UML does
to x86-64 syscall table.

Note: I noted a bogus:
	[ __NR_sched_yield ] = (syscall_handler_t *) yield,

while doing this patch (which could only be a workaround for some strange bug,
but I would ignore this possibility).  I'm changing this without notice.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01 08:58:55 -07:00
Paolo 'Blaisorblade' Giarrusso 5e7b83ffc6 [PATCH] uml: fix syscall table by including $(SUBARCH)'s one, for i386
Split the i386 entry.S files into entry.S and syscall_table.S which is
included in the previous one (so actually there is no difference between them)
and use the syscall_table.S in the UML build, instead of tracking by hand the
syscall table changes (which is inherently error-prone).

We must only insert the right #defines to inject the changes we need from the
i386 syscall table (for instance some different function names); also, we
don't implement some i386 syscalls, as ioperm(), nor some TLS-related ones
(yet to provide).

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01 08:58:55 -07:00
Paolo 'Blaisorblade' Giarrusso 9c340d80f6 [PATCH] uml: fix compilation for __CHOOSE_MODE addition
I had added the __CHOOSE_MODE syntax to fix some warnings with newer GCC's
in the uml-fix-cond-expr-as-lvalues-warning patch.

Here is the update from the version I sent to make it work also when only
one mode (TT or SKAS) is enabled.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16 15:25:39 -07:00
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
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!
2005-04-16 15:20:36 -07:00