* 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl:
vfs: make no_llseek the default
vfs: don't use BKL in default_llseek
llseek: automatically add .llseek fop
libfs: use generic_file_llseek for simple_attr
mac80211: disallow seeks in minstrel debug code
lirc: make chardev nonseekable
viotape: use noop_llseek
raw: use explicit llseek file operations
ibmasmfs: use generic_file_llseek
spufs: use llseek in all file operations
arm/omap: use generic_file_llseek in iommu_debug
lkdtm: use generic_file_llseek in debugfs
net/wireless: use generic_file_llseek in debugfs
drm: use noop_llseek
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>
Several devices use a high number of bits for scancodes. One important
group is the Remote Controllers. Some new protocols like RC-6 define a
scancode space of 64 bits.
The current EVIO[CS]GKEYCODE ioctls allow replace the scancode/keycode
translation tables, but it is limited to up to 32 bits for scancode.
Also, if userspace wants to clean the existing table, replacing it by
a new one, it needs to run a loop calling the ioctls over the entire
sparse scancode space.
To solve those problems, this patch extends the ioctls to allow drivers
handle scancodes up to 32 bytes long (the length could be extended in
the future should such need arise) and allow userspace to query and set
scancode to keycode mappings not only by scancode but also by index.
Compatibility code were also added to handle the old format of
EVIO[CS]GKEYCODE ioctls.
Folded fixes by:
- Dan Carpenter: locking fixes for the original implementation
- Jarod Wilson: fix crash when setting keycode and wiring up get/set
handlers in original implementation.
- Dmitry Torokhov: rework to consolidate old and new scancode handling,
provide options to act either by index or scancode.
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Split ioctl handling into 3 separate sections: fixed-length ioctls,
variable-length ioctls and multi-number variable length handlers.
This reduces identation and makes the code a bit clearer.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
As all callers are now changed to only use the input_abs_*() access
helpers, switching over to dynamically allocated ABS information is
easy. This reduces size of struct input_dev from 3152 to 1640 on
64 bit architectures.
Signed-off-by: Daniel Mack <daniel@caiaq.de>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Change all call sites in drivers/input to not access the ABS axis
information directly anymore. Make them use the access helpers instead.
Also use input_set_abs_params() when possible.
Did some code refactoring as I was on it.
Signed-off-by: Daniel Mack <daniel@caiaq.de>
Cc: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
With the rapidly increasing number of intelligent multi-contact and
multi-user devices, the need to send digested, filtered information
from a set of different sources within the same device is imminent.
This patch adds the concept of slots to the MT protocol. The slots
enumerate a set of identified sources, such that all MT events
can be passed independently and selectively per identified source.
The protocol works like this: Instead of sending a SYN_MT_REPORT
event immediately after the contact data, one sends an ABS_MT_SLOT
event immediately before the contact data. The input core will only
emit events for slots with modified MT events. It is assumed that
the same slot is used for the duration of an initiated contact.
Acked-by: Ping Cheng <pingc@wacom.com>
Acked-by: Chase Douglas <chase.douglas@canonical.com>
Acked-by: Rafi Rubin <rafi@seas.upenn.edu>
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
When the client buffer is very small and wraps around a lot, it may
well be that a write increases the head such that head == tail. If
this happens between the point where a poll is triggered and the
actual data is being read, there will be no data to read. This is
confusing to applications, which might end up closing the file.
This patch solves the problem by making sure the client buffer is
never empty after writing to it.
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Some devices, in particular MT devices, produce a lot of data. This
may lead to overflowing of the event queues in evdev driver, which
by default are fairly small. Let the drivers hint the average number
of events per packet generated by the device, and use that information
when computing the buffer size evdev should use for the device.
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
Acked-by: Chase Douglas <chase.douglas@canonical.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Allocate the event buffer dynamically, and prepare to compute the
buffer size in a separate function. This patch defines the size
computation to be identical to the current code, and does not contain
any logical changes.
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
The HID layer has some scan codes of the form 0xffbc0000 for logitech
devices which do not work if scancode is typed as signed int, so we need
to switch to unsigned it instead. While at it keycode being signed does
not make much sense either.
Acked-by: Márton Németh <nm127@freemail.hu>
Acked-by: Matthew Garrett <mjg@redhat.com>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Seeking does not make sense for input interfaces such as evdev and joydev
so let's use nonseekable_open to mark them non-seekable.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
When using realtime signals, we'll enqueue one signal for every event.
This is unfortunate, because (for example) keyboard presses are three
events: key, msc scancode, and syn. They'll be enqueued fast enough in
kernel space that all three events will be ready to read by the time
userspace runs, so the first invocation of the signal handler will read
all three events, but then the second two invocations still have to run
to do no work.
Instead, only send the SIGIO notification on syn events. This is a
slight abuse of SIGIO semantics, in principle it ought to fire as soon
as any events are readable. But it matches evdev semantics, which is
more important since SIGIO is rather vaguely defined to begin with.
Signed-off-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Commit 3d5cb60e ("Input: simplify name handling for certain input
handles") introduced a regression for the EVIOCGNAME/JSIOCGNAME
ioctl.
Before this, patch, the platform device's name was given back to
userspace which was good to identify devices. After this patch, the
device is ("event%d", minor) which is not descriptive at all.
This fixes the behaviour by taking dev->name.
Reported-by: Sven Neumann <s.neumann@raumfeld.com>
Signed-off-by: Daniel Mack <daniel@caiaq.de>
Reviewed-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Synaptics uses anisotropic coordinate system. On some wide touchpads
vertical resolution can be twice as high as horizontal which causes
unequal sensitivity on x/y directions. Add support for reading the
resolution with EVIOCGABS ioctl.
Signed-off-by: Tero Saarni <tero.saarni@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
For evdev, joydev and mousedev, instead of having a separate character array
holding name of the handle, use struct devce's name which is the same.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
