Commit Graph

178 Commits

Author SHA1 Message Date
Dmitry Torokhov
00159f19a5 Input: do not emit unneeded EV_SYN when suspending
Do not emit EV_SYN/SYN_REPORT on suspend if there were no keys that are
still pressed as we are suspending the device (and in all other cases when
input core is forcibly releasing keys via input_dev_release_keys() call).

Reviewed-by: Benson Leung <bleung@chromium.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2015-08-07 14:55:38 -07:00
Anshul Garg
3e2b03dad5 Input: use for_each_set_bit() where appropriate
Instead of iterating over all bits in a bitmap and test them individually
let's siwtch to for_each_set_bit() which is more compact and is also
faster.

Also use bitmap_weight() when counting number of set bits.

This also fixes INPUT_DO_TOGGLE() implementation as it should have used
*_CNT as the upper boundary, not *_MAX.

Signed-off-by: Anshul Garg <aksgarg1989@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2015-06-25 14:44:36 -07:00
Shailendra Verma
ec8beff964 Input: fix typo in comment to input_handler_for_each_handle()
Signed-off-by: Shailendra Verma <shailendra.capricorn@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2015-05-20 14:45:41 -07:00
Anshul Garg
2c50ad340c Input: do not try to filter out events if handler is not a filter
If given input handler is not a filter there is no point is iterating list
of events in a packet to see if some of them need to be filtered out.

Signed-off-by: Anshul Garg <anshul.g@samsung.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2015-01-08 13:53:34 -08:00
Anshul Garg
5ab1714570 Input: small tweak to autorepeat handling
If a device does not support autorepeat or does not emit any key events we
should not be scanning all events in a packet to decide if we should start
or stop autorepeat function.

Signed-off-by: Anshul Garg <anshul.g@samsung.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2015-01-08 13:53:30 -08:00
Anshul Garg
baf332c0f1 Input: optimize events_per_packet count calculation
This patch avoids unnecessary operations while estimating events per
packet for an input device when event type is not set.

Signed-off-by: Anshul Garg <anshul.g@samsung.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2014-12-15 21:45:55 -08:00
Aniroop Mathur
9c7d66fa9b Input: initialize input_no to -1 to avoid subtraction
Let's initializes input_no to -1 in order to avoid extra subtraction
operation performed every time we allocate an input device.

Signed-off-by: Aniroop Mathur <aniroop.mathur@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2014-12-02 21:34:49 -08:00
Richard Leitner
bf1d50fa74 Input: avoid negative input device numbers
Fix the format string for input device name generation to avoid negative
device numbers when the id exceeds the maximum signed integer value.

Signed-off-by: Richard Leitner <richard.leitner@skidata.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2014-10-09 15:27:24 -07:00
Dmitry Torokhov
2c9a9cfec0 Input: automatically set EV_ABS bit in input_set_abs_params
Let's automatically set EV_ABS bit in device's event type list when calling
input_set_abs_params() so that drivers do not have to do it explicitly.

These calls are never in a hot paths so we won't lose much time by setting
the same bit several times.

Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2014-10-08 11:06:12 -07:00
Dmitry Torokhov
50c5d36dab Input: fix defuzzing logic
We attempt to remove noise from coordinates reported by devices in
input_handle_abs_event(), unfortunately, unless we were dropping the
event altogether, we were ignoring the adjusted value and were passing
on the original value instead.

Cc: stable@vger.kernel.org
Reviewed-by: Andrew de los Reyes <adlr@chromium.org>
Reviewed-by: Benson Leung <bleung@chromium.org>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2014-07-20 13:17:42 -07:00
Dmitry Torokhov
55df811f20 Merge branch 'next' into for-linus
First round of input updates for 3.14.
2014-01-23 08:10:44 -08:00
Dmitry Torokhov
28a2a2e1ae Input: allocate absinfo data when setting ABS capability
We need to make sure we allocate absinfo data when we are setting one of
EV_ABS/ABS_XXX capabilities, otherwise we may bomb when we try to emit this
event.

Rested-by: Paul Cercueil <pcercuei@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2013-12-31 10:53:19 -08:00
Aleksej Makarov
768d9aa557 Input: don't call input_dev_release_keys() in resume
When waking up the platform by pressing a specific key, sending a
release on that key makes it impossible to react on the event in
user-space. This is fixed by moving the input_reset_device() call to
resume instead.

[dmitry.torokhov@gmail.com: make sure we still restore LED/sound state
after resume, handle hibernation properly]

Signed-off-by: Aleksej Makarov <aleksej.makarov@sonymobile.com>
Signed-off-by: Oskar Andero <oskar.andero@sonymobile.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2013-12-16 02:19:10 -08:00
Dmitry Torokhov
42249094f7 Merge branch 'next' into for-linus
Merge first round of changes for 3.13 merge window.
2013-11-14 17:38:05 -08:00
Kang Hu
95079b8aa8 Input: remove a redundant max() call
dev->hint_events_per_packet is guaranteed to be >= packet_size.
so an extra max() call is not needed.

Signed-off-by: Kang Hu <hukangustc@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2013-10-31 08:46:07 -07:00
David Herrmann
a60a71b035 Input: move name/timer init to input_alloc_dev()
We want to allow drivers to call input_event() at any time after the
device got allocated. This means input_event() and input_register_device()
must be allowed to run in parallel.

The only conflicting calls in input_register_device() are init_timer() and
dev_set_name(). Both can safely be moved to device allocation and we're
good to go.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2013-10-06 01:23:26 -07:00
Dmitry Torokhov
b666263b71 Input: document that unregistering managed devices is not necessary
Apparently some users of managed input devices are confused whether
input_unregister_device() is needed when working with them. Clarify
this in the kernel doc for devm_input_allocate_device(): in most cases
there is no need to call neither input_unregister_device() nor
input_free_device() when working with managed devices.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2013-01-09 09:07:56 -08:00
Dmitry Torokhov
2be975c6d9 Input: introduce managed input devices (add devres support)
There is a demand from driver's writers to use managed devices framework
for their drivers. Unfortunately up to this moment input devices did not
provide support for managed devices and that lead to mixing two styles
of resource management which usually introduced more bugs, such as
manually unregistering input device but relying in devres to free
interrupt handler which (unless device is properly shut off) can cause
ISR to reference already freed memory.

This change introduces devm_input_allocate_device() that will allocate
managed instance of input device so that driver writers who prefer
using devm_* framework do not have to mix 2 styles.

Reviewed-by: Henrik Rydberg <rydberg@euromail.se>
Reviewed-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2012-11-08 09:10:05 -08:00
Dmitry Torokhov
adc4633c86 Input: fix sparse warning in __input_release_device()
This fixes the following warning:
drivers/input/input.c:538:23: error: incompatible types in comparison expression (different address spaces)

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2012-10-25 00:12:01 -07:00
Dmitry Torokhov
7f8d4cad1e Input: extend the number of event (and other) devices
Extend the amount of character devices, such as eventX, mouseX and jsX,
from a hard limit of 32 per input handler to about 1024 shared across
all handlers.

To be compatible with legacy installations input handlers will start
creating char devices with minors in their legacy range, however once
legacy range is exhausted they will start allocating minors from the
dynamic range 256-1024.

Reviewed-by: David Herrmann <dh.herrmann@googlemail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2012-10-08 09:37:55 -07:00
Dmitry Torokhov
7774036808 Merge branch 'for-next' of git://github.com/rydberg/linux into next
Merge Henrik's updates to multitouch code. Even though Jiri already
pulled them in I need to do it too since my changes to evdev using
dynamic major would clash with them.
2012-10-01 14:40:51 -07:00
Henrik Rydberg
4369c64c79 Input: Send events one packet at a time
On heavy event loads, such as a multitouch driver, the irqsoff latency
can be as high as 250 us.  By accumulating a frame worth of data
before passing it on, the latency can be dramatically reduced.  As a
side effect, the special EV_SYN handling can be removed, since the
frame is now atomic.

This patch adds the events() handler callback and uses it if it
exists. The latency is improved by 50 us even without the callback.

Cc: Daniel Kurtz <djkurtz@chromium.org>
Tested-by: Benjamin Tissoires <benjamin.tissoires@enac.fr>
Tested-by: Ping Cheng <pingc@wacom.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
2012-09-19 19:50:18 +02:00
Henrik Rydberg
352ac4bd01 Input: Move autorepeat to the event-passing phase
Preparing to split event filtering and event passing, move the
autorepeat function to the point where the event is actually passed.

Tested-by: Benjamin Tissoires <benjamin.tissoires@enac.fr>
Tested-by: Ping Cheng <pingc@wacom.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
2012-09-19 19:50:17 +02:00
Henrik Rydberg
0672120a2e Input: Make sure we follow all EV_KEY events
For some EV_KEY types, sending a larger-than-one value causes the
input state to oscillate. This patch makes sure this cannot happen,
clearing up the autorepeat bypass logic in the process.

Tested-by: Benjamin Tissoires <benjamin.tissoires@enac.fr>
Tested-by: Ping Cheng <pingc@wacom.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
2012-09-19 19:50:17 +02:00
Henrik Rydberg
7c75bf9927 Input: Improve the events-per-packet estimate
The events-per-packet estimate has so far been used by MT devices
only. This patch adjusts the packet buffer size to also accomodate the
KEY and MSC events.  Keyboards normally send one or two keys at a
time. MT devices normally send a number of button keys along with the
MT information.  The buffer size chosen here covers those cases, and
matches the default buffer size in evdev. Since the input estimate is
now preferred, remove the special input-mt estimate.

Reviewed-and-tested-by: Ping Cheng <pingc@wacom.com>
Tested-by: Benjamin Tissoires <benjamin.tissoires@enac.fr>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
2012-09-19 19:50:17 +02:00
Henrik Rydberg
8d18fba282 Input: Break out MT data
Move all MT-related things to a separate place. This saves some
bytes for non-mt input devices, and prepares for new MT features.

Reviewed-and-tested-by: Benjamin Tissoires <benjamin.tissoires@enac.fr>
Tested-by: Ping Cheng <pingc@wacom.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
2012-09-19 19:50:17 +02:00
Dmitry Torokhov
c0bb1f975c Input: get rid of MATCH_BIT() macro
MATCH_BIT() is ugly and stupid, we have much nicer bitmap_subset() which
does the same and does not hide control flow.

Reported-by: Baodong Chen <chenbdchenbd@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2012-08-21 22:29:52 -07:00
Henrik Rydberg
b89529a10c Input: Use accessor for MT values
The current MT accessor function does not distinguish between the MT
values and the slot specification event. Add an accessor function for
the values only, and use it where appropriate.

Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
2012-02-02 14:42:20 +01:00
Al Viro
2c9ede55ec switch device_get_devnode() and ->devnode() to umode_t *
both callers of device_get_devnode() are only interested in lower 16bits
and nobody tries to return anything wider than 16bit anyway.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:54:55 -05:00
Hans Petter Selasky
8c127f0717 Input: properly assign return value of clamp() macro.
[dtor@mail.ru: added mousedev changes]
Signed-off-by: Hans Petter Selasky <hselasky@c2i.net>
Cc: stable@kernel.org
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2011-05-25 09:24:58 -07:00
Eric Dumazet
7cbbb758d3 Input: remove useless synchronize_rcu() calls
There is no need to call synchronize_rcu() after a list insertion,
or a NULL->ptr assignment.

However, the reverse operations do need this call.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2011-05-12 08:28:57 -07:00
Jeff Brown
80b4895aa4 Input: estimate number of events per packet
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: Jeff Brown <jeffbrown@android.com>
Reviewed-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2011-04-18 10:15:43 -07:00
Dmitry Torokhov
97eb3f2435 Merge branch 'next' into for-linus 2011-03-18 23:38:50 -07:00
Dmitry Torokhov
9ae4345a46 Revert "Input: do not pass injected events back to the originating handler"
This reverts commit 5fdbe44d03.

Apparently there exist userspace programs that expect to be able to
"loop back" and distribute to readers events written into
/dev/input/eventX and this change made for the benefit of SysRq
handler broke them. Now that SysRq uses alternative method to suppress
filtering of the events it re-injects we can safely revert this change.

Reported-by: Kristen Carlson Accardi <kristen@linux.intel.com>
Cc: stable@kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2011-02-02 23:04:27 -08:00
Dmitry Torokhov
aebd636bd6 Input: switch completely over to the new versions of get/setkeycode
All users of old style get/setkeycode methids have been converted so
it is time to retire them.

Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2011-01-31 21:16:59 -08:00
Linus Torvalds
31b6ca0af7 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (58 commits)
  Input: wacom_w8001 - support pen or touch only devices
  Input: wacom_w8001 - use __set_bit to set keybits
  Input: bu21013_ts - fix misuse of logical operation in place of bitop
  Input: i8042 - add Acer Aspire 5100 to the Dritek list
  Input: wacom - add support for digitizer in Lenovo W700
  Input: psmouse - disable the synaptics extension on OLPC machines
  Input: psmouse - fix up Synaptics comment
  Input: synaptics - ignore bogus mt packet
  Input: synaptics - add multi-finger and semi-mt support
  Input: synaptics - report clickpad property
  input: mt: Document interface updates
  Input: fix double equality sign in uevent
  Input: introduce device properties
  hid: egalax: Add support for Wetab (726b)
  Input: include MT library as source for kerneldoc
  MAINTAINERS: Update input-mt entry
  hid: egalax: Add support for Samsung NB30 netbook
  hid: egalax: Document the new devices in Kconfig
  hid: egalax: Add support for Wetab
  hid: egalax: Convert to MT slots
  ...

Fixed up trivial conflict in drivers/input/keyboard/Kconfig
2011-01-07 14:45:47 -08:00
Dmitry Torokhov
554738da71 Merge branch 'next' into for-linus
Conflicts:
	include/linux/input.h
2011-01-06 22:34:59 -08:00
Dmitry Torokhov
5c461b913a Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rydberg/input-mt into next 2010-12-27 17:33:20 -08:00
Henrik Rydberg
fcd3027abb Input: fix double equality sign in uevent
Looking at the uevent stream for input devices, all properties are on
the form "A=B" except the bitmap values, which are on the form
"A==B". This bug has been around at least since 2007, and the input
uevent code has been untouched since. The recent addition of device
properties suggests this is a good time for a remedy.

Acked-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
2010-12-20 09:37:37 +01:00
Henrik Rydberg
85b7720039 Input: introduce device properties
Today, userspace sets up an input device based on the data it emits.
This is not always enough; a tablet and a touchscreen may emit exactly
the same data, for instance, but the former should be set up with a
pointer whereas the latter does not need to. Recently, a new type of
touchpad has emerged where the buttons are under the pad, which
changes logic without changing the emitted data. This patch introduces
a new ioctl, EVIOCGPROP, which enables user access to a set of device
properties useful during setup. The properties are given as a bitmap
in the same fashion as the event types, and are also made available
via sysfs, uevent and /proc/bus/input/devices.

Acked-by: Ping Cheng <pingc@wacom.com>
Acked-by: Chase Douglas <chase.douglas@canonical.com>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
2010-12-20 09:37:33 +01:00
Dmitry Torokhov
67b989a0c1 Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rydberg/input-mt into next
Conflicts:
	drivers/input/Makefile
2010-12-16 09:17:48 -08:00
Henrik Rydberg
47c78e8913 input: mt: Break out slots handling
In preparation for common code to handle a larger set of MT slots
devices, move the slots handling over to a separate file.

Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
2010-12-16 10:39:57 +01:00
Joe Perches
da0c490115 Input: use pr_fmt and pr_<level>
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2010-11-30 23:10:26 -08:00
Linus Torvalds
864ee6cb22 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: fix typo in keycode validation supporting large scancodes
  Input: aiptek - tighten up permissions on sysfs attributes
  Input: sysrq - pass along lone Alt + SysRq
2010-11-19 10:31:04 -08:00
Mattia Dongili
de391d1250 Input: fix typo in keycode validation supporting large scancodes
Check the input_keymap_entry keycode size (u32) instead of the device's
(void*) when validating that keycode value can be stored in the keymap.

Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=22722

Signed-off-by: Mattia Dongili <malattia@linux.it>
Tested-by: Norbert Preining <preining@logic.at>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2010-11-18 09:20:42 -08:00
Arnd Bergmann
451a3c24b0 BKL: remove extraneous #include <smp_lock.h>
The big kernel lock has been removed from all these files at some point,
leaving only the #include.

Remove this too as a cleanup.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-17 08:59:32 -08:00
Dmitry Torokhov
5fdbe44d03 Input: do not pass injected events back to the originating handler
Sometimes input handlers (as opposed to input devices) have a need to
inject (or re-inject) events back into input core. For example sysrq
filter may want to inject previously suppressed Alt-SysRq so that user
can take a screen print. In this case we do not want to pass such events
back to the same same handler that injected them to avoid loops.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2010-11-11 01:01:26 -08:00
Dmitry Torokhov
b50b521694 Input: export input_reset_device() for use in KGDB
KGDB, much like the resume process, needs to be able to mark all keys that
were pressed at the time we dropped into the debuggers as "released", since
it is unlikely that the keys stay pressed for the entire duration of the
debug session.

Also we need to make sure that input_reset_device() and input_dev_suspend()
only attempt to change state of currenlt opened devices since closed devices
may not be ready to accept IO requests.

Tested-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2010-11-03 11:04:46 -07:00
Linus Torvalds
3a99c63190 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (75 commits)
  Input: wacom - specify Cinitq supported tools
  Input: ab8500-ponkey - fix IRQ freeing in error path
  Input: adp5588-keys - use more obvious i2c_device_id name string
  Input: ad7877 - switch to using threaded IRQ
  Input: ad7877 - use attribute group to control visibility of attributes
  Input: serio - add support for PS2Mult multiplexer protocol
  Input: wacom - properly enable runtime PM
  Input: ad7877 - filter events where pressure is beyond the maximum
  Input: ad7877 - implement EV_KEY:BTN_TOUCH reporting
  Input: ad7877 - implement specified chip select behavior
  Input: hp680_ts_input - use cancel_delayed_work_sync()
  Input: mousedev - correct lockdep annotation
  Input: ads7846 - switch to using threaded IRQ
  Input: serio - support multiple child devices per single parent
  Input: synaptics - simplify pass-through port handling
  Input: add ROHM BU21013 touch panel controller support
  Input: omap4-keypad - wake-up on events & long presses
  Input: omap4-keypad - fix interrupt line configuration
  Input: omap4-keypad - SYSCONFIG register configuration
  Input: omap4-keypad - use platform device helpers
  ...
2010-10-25 07:59:01 -07:00
Arnd Bergmann
6038f373a3 llseek: automatically add .llseek fop
All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.

The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.

New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time.  Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.

The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.

Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.

Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.

===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
//   but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{
<+...
nonseekable_open(...)
...+>
}

@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{
<+...
(
nonseekable_open(...)
|
nested_open(...)
)
...+>
}

@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
<+...
(
   *off = E
|
   *off += E
|
   func(..., off, ...)
|
   E = *off
)
...+>
}

@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}

@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
<+...
(
  *off = E
|
  *off += E
|
  func(..., off, ...)
|
  E = *off
)
...+>
}

@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}

@ fops0 @
identifier fops;
@@
struct file_operations fops = {
 ...
};

@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
 .llseek = llseek_f,
...
};

@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
 .read = read_f,
...
};

@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
 .write = write_f,
...
};

@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
 .open = open_f,
...
};

// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
...  .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};

@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
...  .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};

// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
...  .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};

// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};

// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};

@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+	.llseek = default_llseek, /* write accesses f_pos */
};

// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////

@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
 .write = write_f,
 .read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};

@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};

@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};

@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Julia Lawall <julia@diku.dk>
Cc: Christoph Hellwig <hch@infradead.org>
2010-10-15 15:53:27 +02:00