tty_sem used to protect tty open count. This was removed in 33dd474a
but the lock remained in place.

So remove it completely as it protects nothing now.

Also this solves Mac's problem with inatomic operation called from
atomic context (ppp):
BUG: scheduling while atomic: firefox-bin/1992/0x10000800
Modules linked in: ...
Pid: 1992, comm: firefox-bin Not tainted 2.6.38 #1
Call Trace:
...
 [] ? mutex_lock+0xe/0x21
 [] ? ntty_write+0x5d/0x192 [nozomi]
 [] ? __mod_timer.clone.30+0xbe/0xcc
 [] ? check_preempt_curr+0x60/0x6d
 [] ? __nf_ct_refresh_acct+0x75/0xbe
 [] ? ppp_async_push+0xa9/0x3bd [ppp_async]
 [] ? ppp_async_send+0x34/0x40 [ppp_async]
 [] ? ppp_push+0x6c/0x4f9 [ppp_generic]
...
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Reported-by: NMac <kmac@poczta.fm>
Tested-by: NGerald Pfeifer <gerald@pfeifer.com>
Reviewed-by: NJack Stone <jwjstone@fastmail.fm>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Before 33dd474a, these were some kind of protection against race with
HUP. They were protected with port->tty_sem at the same time.

By that commit, the counting was switched to tty_port's one, but the
locking remained the old one. So the count was not protected by
any lock anymore.

The driver should not test whether it raced with HUP or not anyways.
With the new refcounted tty model, it just should proceed as nothing
happened because all needed info is still there. In respect to this,
let's drop the useless and unprotected tests (tty_port->count is
protected by tty_port->lock).
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Tested-by: NGerald Pfeifer <gerald@pfeifer.com>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The allocation was moved to probe function in 9842c38e. And we can
sleep there. So allocate the 4*8192 bytes as GFP_KERNEL to mitigate
the allocation failure.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Tested-by: NGerald Pfeifer <gerald@pfeifer.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

it makes it simpler to keep track of the amount of
bytes received and simplifies how flush_to_ldisc counts
the remaining bytes. It also fixes a bug of lost bytes
on n_tty when flushing too many bytes via the USB
serial gadget driver.
Tested-by: NStefan Bigler <stefan.bigler@keymile.com>
Tested-by: NToby Gray <toby.gray@realvnc.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Remove stale code in serial_core layer.

Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NGovindraj.R <govindraj.raja@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Traditional \E[2J sequence erases console display but scroll-back
buffer and underlying device (frame) buffer keep data that can be
accessed by scrolling console back.

This patch introduce new \E[J parameter 3 that allows to scramble
scroll-back buffer explicitly. Session locking programs (screen,
vlock) can use it to prevent attacker to browse locked console
history.
Signed-off-by: NPetr Písař <ppisar@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Including linux/tty.h 3 times is a little over the top - once will do.
Signed-off-by: NJesper Juhl <jj@chaosbits.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

remove invalid location line in each file header after location
moved from driver/char to driver/tty
Signed-off-by: NJovi Zhang <bookjovi@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Now, uart_update_termios is empty, so it's time to remove it. We no
longer need a live tty in .dtr_rts. So this should prune all the bugs
where tty is zeroed in port->tty during tty_port_block_til_ready.

There is one thing to note. We don't set ASYNC_NORMAL_ACTIVE now. It's
because this is done already in tty_port_block_til_ready.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

In .dtr_rts we do:
  uart_set_mctrl(uport, TIOCM_DTR | TIOCM_RTS)
and call uart_update_termios. It does:
  uart_set_mctrl(port, TIOCM_DTR | TIOCM_RTS)
once again. As the only callsite of uart_update_termios is .dtr_rts,
remove the uart_set_mctrl from uart_update_termios to not set it twice.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

We should not fiddle with speed and cflags in .dtr_rts hook. Actually
we might not have tty at that moment already.

So move the console cflag copy and speed setup into uart_startup.
Actually the speed setup is already there, but we need to call it
unconditionally (uart_startup is called from uart_open with hw_init =
0).

This means we move uart_change_speed before dtr/rts setup in .dtr_rts.
But this should not matter as the setup should be called after
uart_change_speed anyway.
Before:                             After:
dtr/rts setup (dtr_rts)             uart_change_speed (startup)
uart_change_speed (update_termios)  dtr/rts setup (dtr_rts)
dtr/rts setup (update_termios)      dtr/rts setup (update_termios)

The second setup will dismiss with the next patch.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The bit is set in tty_port_block_til_ready (via moxa_open) and unset
in tty_port_close (via moxa_close). No need to pin it in the driver.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Devices extracted from device tree all seem to have pdev->id set to -1.
Up until now we mapped all devices with id -1 to the first device.  This
behaviour could lead to problems when using more than one Altera UART in
a system.

This patch changes the behaviour of the driver to scan for the next free
id in case the id is -1.

Because we cannot refer back to the assigned id in altera_uart_remove,
the port instance needs to be stored in device drvdata.
Reported-by: NDavid Smoot <davidsmoot@gmail.com>
Cc: Anton Vorontsov <cbouatmailru@gmail.com>
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

When tty_add_file fails we omit to clean up. Fix that by calling
tty_release appropriatelly.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Used the newly introduced deinitialize_tty_struct to properly shut
down ldisc.

It is intended to fix the Julian's reported problem. He reports that
kmemleak checker warns about memory leak:
unreferenced object 0xc0e19860 (size 8):
comm cat, pid 1226, jiffies 4294919464 (age 287.476s)
hex dump (first 8 bytes):
44 de 2d c1 01 00 00 00 D.-.....
backtrace:
[<c1065a74>] create_object+0x109/0x1ad
[<c1063d2b>] kmem_cache_alloc+0x60/0x68
[<c113505c>] tty_ldisc_get+0x54/0x76
[<c11358c9>] tty_ldisc_init+0xa/0x20
[<c1130ab4>] initialize_tty_struct+0x2d/0x1ac
[<c1130c8c>] tty_init_dev+0x59/0x10d
[<c113136d>] tty_open+0x24a/0x3a2
...
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Reported-by: NJulian Anastasov <ja@ssi.bg>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Introduce deinitialize_tty_struct which should be called after
initialize_tty_struct and before successfull tty_ldisc_setup.

It calls tty_ldisc_deinit which is opposite of tty_ldisc_init. It only
puts a reference to ldisc and assigns NULL to tty->ldisc.

It will be used to shut down ldisc when tty_release cannot be called
yet.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Change it so that we call the deinit functions at one place at the end
of the function (by gotos). And while at it use some sane label names.

This is a preparation for the deinitialization of tty in the next
patch.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Change it so that we call the deinit functions at one place at the end
of the function (by gotos). And while at it use some sane label names.

This is a preparation for the deinitialization of tty in the next
patch.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Change it so that we call the deinit functions at one place at the end
of the function (by gotos). And while at it use some sane label names.

This is a preparation for the deinitialization of tty in the next
patch.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/tty/rocket.c:1393:2: warning: Value stored to 'cp' is never read
        cp = &info->channel;
        ^    ~~~~~~~~~~~~~~
drivers/tty/rocket.c:1412:2: warning: Value stored to 'cp' is never read
        cp = &info->channel;
        ^    ~~~~~~~~~~~~~~
drivers/tty/rocket.c:1730:2: warning: Value stored to 'cp' is never read
        cp = &info->channel;
        ^    ~~~~~~~~~~~~~~
drivers/tty/rocket.c:1825:3: warning: Value stored to 'str' is never read
                str = "8";
                ^     ~~~
[many 'str' warnings stripped]
drivers/tty/rocket.c:2037:3: warning: Value stored to 'board_type' is never read
                board_type = "RocketModem";
                ^            ~~~~~~~~~~~~~
[some 'board_type' warnings stripped]
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/tty/moxa.c:1287:2: warning: Value stored to 'port' is never read
        port = tty->index;
        ^      ~~~~~~~~~~
drivers/tty/moxa.c:1763:2: warning: Value stored to 'cflag' is never read
        cflag = termio->c_cflag;        /* termio->c_cflag */
        ^       ~~~~~~~~~~~~~~~
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/tty/vt/vt.c:892:2: warning: Value stored to 'old_screen_size' is never read
        old_screen_size = vc->vc_screenbuf_size;
        ^                 ~~~~~~~~~~~~~~~~~~~~~
drivers/tty/vt/vt.c:890:2: warning: Value stored to 'old_cols' is never read
	old_cols = vc->vc_cols;
	^          ~~~~~~~~~~~
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/tty/cyclades.c:1454:2: warning: Value stored to 'channel' is never read
	channel = info->line - card->first_line;
	^         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Fix it by moving it to the appropriate debug section where it is used.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/tty/serial/serial_core.c:1980:2: warning: Value stored to 'tty' is never read
        tty = port->tty;
        ^     ~~~~~~~~~
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Acked-by: NGovindraj.R <govindraj.raja@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/tty/vt/vt_ioctl.c:1525:2: warning: Value stored to 'kbd' is never read
kbd = kbd_table + console;
^     ~~~~~~~~~~~~~~~~~~~
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Cc: Arthur Taylor <art@ified.ca>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

After adding support for K_OFF in KDSKBMODE, it was forgotten to
add support for returning it in KDGKBMODE.
Signed-off-by: NArthur Taylor <art@ified.ca>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The current check is uneeded, since !retval will always returns true,
as retval returned from tty_add_file is checked earlier and tty_open
exits if it's not zero.
Acked-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NHerton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

* 'for-39-rc4' of git://codeaurora.org/quic/kernel/davidb/linux-msm:
  msm: timer: fix missing return value
  msm: Remove extraneous ffa device check

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: xen-kbdfront - fix mouse getting stuck after save/restore
  Input: estimate number of events per packet
  Input: evdev - indicate buffer overrun with SYN_DROPPED
  Input: document event types and codes and their intended use
  Input: add KEY_IMAGES specifically for AL Image Browser
  Input: twl4030_keypad - fix potential NULL dereference in twl4030_kp_probe()
  Input: h3600_ts - fix error handling at connect
  Input: twl4030_keypad - avoid potential NULL-pointer dereference

* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  block: add blk_run_queue_async
  block: blk_delay_queue() should use kblockd workqueue
  md: fix up raid1/raid10 unplugging.
  md: incorporate new plugging into raid5.
  md: provide generic support for handling unplug callbacks.
  md - remove old plugging code.
  md/dm - remove remains of plug_fn callback.
  md: use new plugging interface for RAID IO.
  block: drop queue lock before calling __blk_run_queue() for kblockd punt
  Revert "block: add callback function for unplug notification"
  block: Enhance new plugging support to support general callbacks

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc/powermac: Build fix with SMP and CPU hotplug
  powerpc/perf_event: Skip updating kernel counters if register value shrinks
  powerpc: Don't write protect kernel text with CONFIG_DYNAMIC_FTRACE enabled
  powerpc: Fix oops if scan_dispatch_log is called too early
  powerpc/pseries: Use a kmem cache for DTL buffers
  powerpc/kexec: Fix regression causing compile failure on UP
  powerpc/85xx: disable Suspend support if SMP enabled
  powerpc/e500mc: Remove CPU_FTR_MAYBE_CAN_NAP/CPU_FTR_MAYBE_CAN_DOZE
  powerpc/book3e: Fix CPU feature handling on 64-bit e5500
  powerpc: Check device status before adding serial device
  powerpc/85xx: Don't add disabled PCIe devices

* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: (24 commits)
  Btrfs: fix free space cache leak
  Btrfs: avoid taking the chunk_mutex in do_chunk_alloc
  Btrfs end_bio_extent_readpage should look for locked bits
  Btrfs: don't force chunk allocation in find_free_extent
  Btrfs: Check validity before setting an acl
  Btrfs: Fix incorrect inode nlink in btrfs_link()
  Btrfs: Check if btrfs_next_leaf() returns error in btrfs_real_readdir()
  Btrfs: Check if btrfs_next_leaf() returns error in btrfs_listxattr()
  Btrfs: make uncache_state unconditional
  btrfs: using cached extent_state in set/unlock combinations
  Btrfs: avoid taking the trans_mutex in btrfs_end_transaction
  Btrfs: fix subvolume mount by name problem when default mount subvolume is set
  fix user annotation in ioctl.c
  Btrfs: check for duplicate iov_base's when doing dio reads
  btrfs: properly handle overlapping areas in memmove_extent_buffer
  Btrfs: fix memory leaks in btrfs_new_inode()
  Btrfs: check for duplicate iov_base's when doing dio reads
  Btrfs: reuse the extent_map we found when calling btrfs_get_extent
  Btrfs: do not use async submit for small DIO io's
  Btrfs: don't split dio bios if we don't have to
  ...

Rather than pass in some random truncated offset to the pid-related
functions, check that the offset is in range up-front.

This is just cleanup, the previous commit fixed the real problem.

Cc: stable@kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

next_pidmap() just quietly accepted whatever 'last' pid that was passed
in, which is not all that safe when one of the users is /proc.

Admittedly the proc code should do some sanity checking on the range
(and that will be the next commit), but that doesn't mean that the
helper functions should just do that pidmap pointer arithmetic without
checking the range of its arguments.

So clamp 'last' to PID_MAX_LIMIT.  The fact that we then do "last+1"
doesn't really matter, the for-loop does check against the end of the
pidmap array properly (it's only the actual pointer arithmetic overflow
case we need to worry about, and going one bit beyond isn't going to
overflow).

[ Use PID_MAX_LIMIT rather than pid_max as per Eric Biederman ]
Reported-by: NTavis Ormandy <taviso@cmpxchg8b.com>
Analyzed-by: NRobert Święcki <robert@swiecki.net>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Mouse gets "stuck" after restore of PV guest but buttons are in working
condition.

If driver has been configured for ABS coordinates at start it will get
XENKBD_TYPE_POS events and then suddenly after restore it'll start getting
XENKBD_TYPE_MOTION events, that will be dropped later and they won't get
into user-space.

Regression was introduced by hunk 5 and 6 of
5ea5254aa0ad269cfbd2875c973ef25ab5b5e9db
("Input: xen-kbdfront - advertise either absolute or relative
coordinates").

Driver on restore should ask xen for request-abs-pointer again if it is
available. So restore parts that did it before 5ea5254.
Acked-by: NOlaf Hering <olaf@aepfle.de>
Signed-off-by: NIgor Mammedov <imammedo@redhat.com>
[v1: Expanded the commit description]
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

Calculate a default based on the number of ABS axes, REL axes,
and MT slots for the device during input device registration.
Signed-off-by: NJeff Brown <jeffbrown@android.com>
Reviewed-by: NHenrik Rydberg <rydberg@euromail.se>
Signed-off-by: NDmitry Torokhov <dtor@mail.ru>

The free space caching code was recently reworked to
cache all the pages it needed instead of using find_get_page everywhere.

One loop was missed though, so it ended up leaking pages.  This fixes
it to use our page array instead of find_get_page.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

Instead of overloading __blk_run_queue to force an offload to kblockd
add a new blk_run_queue_async helper to do it explicitly.  I've kept
the blk_queue_stopped check for now, but I suspect it's not needed
as the check we do when the workqueue items runs should be enough.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>