copy_from_user() returns the number of bytes remaining but we want to
return a negative error code here.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Revert "tty: Add a new VT mode which is like VT_PROCESS but doesn't require a VT_RELDISP ioctl call"

This reverts commit eec9fe7d.

Ari writes as the reason this should be reverted:
	The problems with this patch include:
	1. There's at least one subtlety I overlooked - switching
	between X servers (i.e. from one X VT to another) still requires
	the cooperation of both X servers. I was assuming that KMS
	eliminated this.
	2. It hasn't been tested at all (no X server patch exists which
	uses the new mode).

As he was the original author of the patch, I'll revert it.

Cc: Ari Entlich <atrigent@ccs.neu.edu>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This new VT mode (VT_PROCESS_AUTO) does everything that VT_PROCESS does
except that it doesn't wait for a VT_RELDISP ioctl before switching
away from a VT with that mode.

If the X server eventually uses this new mode, debugging and crash
recovery should become easier. This is because even when currently in
the VT of a frozen X server it would still be possible to switch out
by doing SysRq-r and then CTRL-<number of a text vt>, sshing in and
doing chvt <number of a text vt>, or any other method of VT switching.
The general concensus on #xorg-devel seems to be that it should be
safe to use this with X now that we have KMS.

This also moves the VT_ACKACQ define to a more appropriate place,
for clarity's sake.
Signed-off-by: NAri Entlich <atrigent@ccs.neu.edu>
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

As this struct is exposed to user space and the API was added for this
release it's a bit of a pain for the C++ world and we still have time to
fix it. Rename the fields before we end up with that pain in an actual
release.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Reported-by: Olivier Goffart
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Call compat_unimap_ioctl, not do_unimap_ioctl.

This was broken by commit e9216651.

The compat_unimap_ioctl was originally called do_unimap_ioctl in
fs/compat_ioctl.h which got moved to drivers/char/vt_ioctl.c.
In that patch, the caller was not updated and consequently called
the native handler.
Signed-off-by: NAndreas Schwab <schwab@linux-m68k.org>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Stanse found (again) a BKL imbalance in vt_ioctl.

It's easily triggerable by ioctl(dev_tty_fd, VT_SETACTIVATE, NULL);

Introduced by

commit d3b5cffc                                 Author: Alan Cox <alan@linux.intel.com>
Date:   Sat Sep 19 13:13:26 2009 -0700

    vt: add an activate and lock
Signed-off-by: NJiri Slaby <jirislaby@gmail.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

vt_waitactive no longer accepts console parameter as console-1
since commit "vt: add an event interface". It expects console
number directly (as viewed by userspace -- counting from 1).

Fix a deadlock suspend regression by redefining adding one
to vt in vt_move_to_console.
Signed-off-by: NJiri Slaby <jirislaby@gmail.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The VT specific compat_ioctl handlers are the only ones
in common code that require the BKL. Moving them into
the vt driver lets us remove the BKL from the other handlers
and cleans up the code.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

X and other graphical interfaces need to be able to flip to a console
and lock it into graphics mode without races.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

In the past someone gratuitiously borrowed chunks of kernel internal vt
code and dumped them in kernel/power. They have all sorts of deep relations
with the vt code so put them in the vt tree instead
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This is needed and requested in various forms for ConsoleKit, screenblank
handling and the like so do the job with a single interface. Also build the
interface so that unlike VT_WAITACTIVE and friends it won't miss events.

FIXME: Should this be a waitactive ioctl or a new device file you can poll
and read events from. We need the code anyway to fix up the existing broken
wait for console switch logic but the ConsoleKit people would prefer the
new device to the ioctl we have here
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

* Remove smp_lock.h from files which don't need it (including some headers!)
* Add smp_lock.h to files which do need it
* Make smp_lock.h include conditional in hardirq.h
  It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT

  This will make hardirq.h inclusion cheaper for every PREEMPT=n config
  (which includes allmodconfig/allyesconfig, BTW)
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Don't return from switch/case directly in vt_ioctl. Set ret and break
instead so that we unlock BKL.
Signed-off-by: NJiri Slaby <jirislaby@gmail.com>
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Cc: stable@kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This is one area where we can't just magic away the bizarre use of
CLOCK_TICK_RATE as it leaks to user space APIs. It also means the visible
CLOCK_TICK_RATE is frozen for architectures which is horrible.

We need to fix this somehow
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

disc_data and driver_data are void *
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Right now we have ifdefs and hooks in the core ioctl handler for TIOCLINUX
and then test if its a console. This is brain dead. Instead call the
tioclinux helper from the relevant driver ioctl methods.
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This moves it to being a tty operation. That removes special cases and now
also means that resize can be picked up by um and other non vt consoles
which may have a resize operation.
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This one could do with some eyeballs on it.  In theory it simply wraps the
ioctl handler in lock/unlock_kernel ready for the lock/unlocks to be pushed
into specific switch values.  To do that means changing the code to return via
a common exit path not all over the place as it does now, hence the big diff
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

As of now, the kernel defaults to non-unicode and XLATE for the keyboard.
We've been changing this in Fedora, but that requires patching the defaults
in the kernel.

The attached introduces CONFIG_VT_UNICODE, which sets the console in
unicode mode by default on boot, including both the virtual terminal and
the keyboard driver.
Signed-off-by: NBill Nottingham <notting@redhat.com>
Cc: Samuel Thibault <samuel.thibault@ens-lyon.org>
Cc: Dmitry Torokhov <dtor@mail.ru>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There have been issues with non-latin1 diacritics and unicode.
http://bugzilla.kernel.org/show_bug.cgi?id=7746

Git 759448f4 `Kernel utf-8 handling'
partly resolved it by adding conversion between diacritics and
unicode. The patch below goes further by just turning diacritics into
unicode, hence providing better future support. The kbd support can be
fetched from
http://bugzilla.kernel.org/attachment.cgi?id=12313

This was tested in all of latin1, latin9, latin2 and unicode with french
and czech dead keys.

Turn the kernel accent_table into unicode, and extend ioctls KDGKBDIACR
and KDSKBDIACR into their equivalents KDGKBDIACRUC and KDSKBDIACR.

New function int conv_uni_to_8bit(u32 uni) for converting unicode into 8bit
_input_.  No, we don't want to store the translation, as it is potentially
sparse and large.
Signed-off-by: NSamuel Thibault <samuel.thibault@ens-lyon.org>
Cc: Jan Engelhardt <jengelh@gmx.de>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Various console drivers are able to resize the screen via the con_resize()
hook.  This hook is also visible in userspace via the TIOCWINSZ, VT_RESIZE and
VT_RESIZEX ioctl's.  One particular utility, SVGATextMode, expects that
con_resize() of the VGA console will always return success even if the
resulting screen is not compatible with the hardware.  However, this
particular behavior of the VGA console, as reported in Kernel Bugzilla Bug
7513, can cause undefined behavior if the user starts with a console size
larger than 80x25.

To work around this problem, add an extra parameter to con_resize().  This
parameter is ignored by drivers except for vgacon.  If this parameter is
non-zero, then the resize request came from a VT_RESIZE or VT_RESIZEX ioctl
and vgacon will always return success.  If this parameter is zero, vgacon will
return -EINVAL if the requested size is not compatible with the hardware.  The
latter is the more correct behavior.

With this change, SVGATextMode should still work correctly while in-kernel and
stty resize calls can expect correct behavior from vgacon.
Signed-off-by: NAntonino Daplas <adaplas@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We should generally prefer to return ERESTARTNOHAND rather than EINTR,
so that processes with unhandled signals that get ignored don't return
EINTR.

This can help with X startup issues:

    Fatal server error:
    xf86OpenConsole: VT_WAITACTIVE failed: Interrupted system call

although the real fix is having the X server always retry EINTR
regardless (since EINTR does happen for signals that have handlers
installed). Keithp has a patch for that.

Regardless, ERESTARTNOHAND is the correct thing to use.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When calling the RELDISP VT ioctl, we are reading vt_newvt while the
console workqueue could be messing with it (through change_console()).  We
fix this race by taking the console semaphore before reading vt_newvt.
Signed-off-by: NSamuel Ortiz <sameo@openedhand.com>
Acked-by: NAntonino Daplas <adaplas@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The new behaviour of CFS exposes a race which occurs if a switch is
requested when vt_mode.mode is VT_PROCESS.

The process with vc->vt_pid is signaled before vc->vt_newvt is set.
This causes the switch to fail when triggered by the monitoing process
because the target is still -1.

[ If the signal sending fails, the subsequent "reset_vc(vc)" will then
  reset vt_newvt to -1, so this works for that case too.   - Linus ]
Signed-off-by: NJan Lübbe <jluebbe@lasnet.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

use __set_current_state(TASK_*) instead of current->state = TASK_*,
Signed-off-by: NMilind Arun Choudhary <milindchoudhary@gmail.com>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

On a multiprocessor machine the VT_WAITACTIVE ioctl call may return 0 if
fg_console has already been updated in redraw_screen() but the console
switch itself hasn't been completed.  Fix this by checking fg_console in
vt_waitactive() with the console sem held.
Signed-off-by: NMichal Januszewski <spock@gentoo.org>
Acked-by: NAntonino Daplas <adaplas@pol.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When the console is in VT_AUTO+KD_GRAPHICS mode, switching to the
SUSPEND_CONSOLE fails, resulting in vt_waitactive() waiting indefinitely or
until the task is interrupted.  This patch tests if a console switch can
occur in set_console() and returns early if a console switch is not
possible.

[akpm@linux-foundation.org: cleanup]
Signed-off-by: NAndrew Johnson <ajohnson@intrinsyc.com>
Acked-by: NPavel Machek <pavel@ucw.cz>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This does several things.
- It moves looking up of the current foreground console into process
  context where we can safely take the semaphore that protects this
  operation.
- It uses the new flavor of work queue processing.
- This generates a factor of do_SAK, __do_SAK that runs immediately.
- This calls __do_SAK with the console semaphore held ensuring nothing
  else happens to the console while we process the SAK operation.
- With the console SAK processing moved into process context this
  patch removes the xchg operations that I used to attempt to attomically
  update struct pid, because of the strange locking used in the SAK processing.
  With SAK using the normal console semaphore nothing special is needed.

Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Run this:

	#!/bin/sh
	for f in $(grep -Erl "\([^\)]*\) *k[cmz]alloc" *) ; do
	  echo "De-casting $f..."
	  perl -pi -e "s/ ?= ?\([^\)]*\) *(k[cmz]alloc) *\(/ = \1\(/" $f
	done

And then go through and reinstate those cases where code is casting pointers
to non-pointers.

And then drop a few hunks which conflicted with outstanding work.

Cc: Russell King <rmk@arm.linux.org.uk>, Ian Molton <spyro@f2s.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Greg KH <greg@kroah.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Paul Fulghum <paulkf@microgate.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Karsten Keil <kkeil@suse.de>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Ian Kent <raven@themaw.net>
Cc: Steven French <sfrench@us.ibm.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Cc: Jaroslav Kysela <perex@suse.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The code has been fixed to use kill_pid instead of kill_proc fix the
comments as well.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

I took a good hard look at the locking and it appears the locking on vt_pid
is the console semaphore.  Every modified path is called under the console
semaphore except reset_vc when it is called from fn_SAK or do_SAK both of
which appear to be in interrupt context.  In addition I need to be careful
because in the presence of an oops the console_sem may be arbitrarily
dropped.

Which leads me to conclude the current locking is inadequate for my needs.

Given the weird cases we could hit because of oops printing instead of
introducing an extra spin lock to protect the data and keep the pid to
signal and the signal to send in sync, I have opted to use xchg on just the
struct pid * pointer instead.

Due to console_sem we will stay in sync between vt_pid and vt_mode except
for a small window during a SAK, or oops handling.  SAK handling should
kill any user space process that care, and oops handling we are broken
anyway.  Besides the worst that can happen is that I try to send the wrong
signal.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This is such a rare path it took me a while to figure out how to test
this after soring out the locking.

This patch does several things.
- The variables used are moved into a structure and declared in vt_kern.h
- A spinlock is added so we don't have SMP races updating the values.
- Instead of raw pid_t value a struct_pid is used to guard against
  pid wrap around issues, if the daemon to spawn a new console dies.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The current kernel serializes console resizes but does not serialize the
resize against the tty structure updates.  This means that while two
parallel resizes cannot mess up the console you can get incorrect results
reported.

Secondly while doing this I added vc_lock_resize() to lock and resize the
console.  This leaves all knowledge of the console_sem in the vt/console
driver and kicks it out of the tty layer, which is good

Thirdly while doing this I decided I couldn't stand "disallocate" any
longer so I switched it to "deallocate".
Signed-off-by: NAlan Cox <alan@redhat.com>
Cc: Paul Fulghum <paulkf@microgate.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

When reading /dev/vcsa while a font with more than 256 characters is
loaded, one of the attribute bits records the 9th bit of the character.
But depending on the console driver (vgacon or fbcon for instance), that's
bit 3 or bit 0.  And there is no way for userland to know that, thus no way
for userland to safely grab the screen content.  So here is a (tested)
patch:

Add a VT_GETHIFONTMASK ioctl for knowing which bit is the 9th bit for VC
text (vc_hi_font_mask field of the vc_data structure).
Signed-off-by: NSamuel Thibault <samuel.thibault@ens-lyon.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NJörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: NAdrian Bunk <bunk@stusta.de>

Mikael Pettersson <mikpe@csd.uu.se> noted that the current 2.6-git (and 2.4)
patch to disallow KDSKBSENT for unpriviledged users should be less restrictive
allowing reading of current function key string entry, but not writing.
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Because people can play games reprogramming keys and leaving traps for the
next user of the console.
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This code uses the x86 (non-AMD-ELAN) value of CLOCK_TICK_RATE instead of
CLOCK_TICK_RATE itself, which is wrong for other archs.
Signed-off-by: NEmmanuel Colbus <emmanuel.colbus@ensimag.imag.fr>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Convert most of the current code that uses _NSIG directly to instead use
valid_signal().  This avoids gcc -W warnings and off-by-one errors.
Signed-off-by: NJesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

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!