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17 commits

Author SHA1 Message Date
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
Jarod Wilson
da48db669f V4L/DVB: IR/imon: remove bad ir_input_dev use
The ir_input_dev gets filled in by __ir_input_register, the one
allocated in imon_init_idev was being overwritten by the correct one
shortly after it was initialized (ultimately resulting in a memory
leak). Additionally, there was an ill-advised memcpy into that
extraneous ir_input_dev which gets fixed by this.

Ill-advised memcpy pointed out by Dmitry Torokhov, bad usage of
ir_input_dev pointed out by Maxim Levitsky.

Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-08-08 23:42:57 -03:00
Jarod Wilson
20cd195972 V4L/DVB: IR/imon: remove incorrect calls to input_free_device
Per Dmitry Torokhov, following input_unregister_device with an
input_free_device is forbidden, the former is sufficient alone.

Acked-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-08-08 23:42:57 -03:00
Joe Perches
abf84383ec V4L/DVB: drivers/media: Remove unnecessary casts of private_data
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Jarod Wilson <jarod@redhat.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-08-02 16:42:53 -03:00
Jarod Wilson
49da8be59b V4L/DVB: IR/imon: auto-configure another 0xffdc device variant
Per Pieter Hoekstra:

I have a Antec Fusion with a iMON Lcd and I get the following error:
imon 6-1:1.0: Unknown 0xffdc device, defaulting to VFD and iMON IR (id
0x9e)

The driver is functional if I load it like this: (I do not use a remote for it)
modprobe imon display_type=1 (On Mythbuntu 10.04/2.6.32)

This device is a lcd-type with support for a MCE remote. Looking at
the source code, this device (0x9e) is the same as id 0x9f.

Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-08-02 15:33:00 -03:00
Jarod Wilson
8a3fa8129c V4L/DVB: IR/imon: use the proper ir-core device unregister function
Was using input_unregister_device directly, instead of using
ir_input_unregister, which tears down a bunch of other things in
addition to eventually calling input_unregister_device.

Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-08-02 14:55:30 -03:00
Jarod Wilson
bbe4690f6c V4L/DVB: IR/imon: add auto-config for 0xffdc rf device
Add auto-config support for iMON 2.4G LT RF device, based on
debug output from Giulio Amodeo in Red Hat bugzilla #572288.

Also flips the switch on only setting up the rf associate sysfs
attr only if we think we're looking at an RF device, vs. previously,
setting up the attr for all 0xffdc devices, so its possible (but a bit
unlikely) there's another iMON RF device we'll have to fix up.

Nb: should be applied after "IR/imon: clean up usage of bools", or there
will be a slight contextual mismatch.

Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-06-01 01:23:26 -03:00
Jarod Wilson
f789bf4013 V4L/DVB: IR/imon: clean up usage of bools
There was a mix of 0/1 and false/true. Pick one convention and stick
with it (I picked false/true).

Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-06-01 01:23:25 -03:00
Jarod Wilson
083e472176 V4L/DVB: IR/imon: remove dead IMON_KEY_RELEASE_OFFSET
On Tue, May 04, 2010 at 06:06:41PM +0200, Dan Carpenter wrote:
> On Tue, May 04, 2010 at 10:03:18AM -0400, Jarod Wilson wrote:
> > @@ -1205,7 +1204,7 @@ static u32 imon_panel_key_lookup(u64 hw_code)
> >  		if (imon_panel_key_table[i].hw_code == (code | 0xffee))
> >  			break;
> >
> > -	keycode = imon_panel_key_table[i % IMON_KEY_RELEASE_OFFSET].keycode;
> > +	keycode = imon_panel_key_table[i].keycode;
> >
> >  	return keycode;
> >  }
>
> There is still potentially a problem here because if we don't hit the
> break statement, then we're one past the end of the array.

D'oh. Okay, here's v2, should fix that buglet too.

This hack was used when the imon driver was using internal key lookup
routines, but became dead weight when the driver was converted to use
ir-core's key lookup routines. These bits simply didn't get removed,
drop 'em now.

Pointed out by Dan Carpenter.

v2: fix possible attempt to access beyond end of key table array,
also pointed out by Dan.

Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-05-19 12:59:17 -03:00
Dan Carpenter
9723dbb034 V4L/DVB: media/IR/imon: potential double unlock on error
If there is an error here we should unlock in the caller (which is
imon_init_intf1()).  We can remove this stray unlock.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-05-19 12:59:04 -03:00
Dan Carpenter
5f6e3c8e34 V4L/DVB: media/IR/imon: testing the wrong variable
There is a typo here.  We meant to test "ir" instead of "props".  The
"props" variable was tested earlier.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-05-19 12:59:03 -03:00
Dan Carpenter
f03900d696 V4L/DVB: media/IR/imon: precendence issue: ! vs ==
The original condition is always false because ! has higher precedence
than == and neither 0 nor 1 is equal to IMON_DISPLAY_TYPE_VGA.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-05-19 12:59:03 -03:00
Jarod Wilson
db190fc13a V4L/DVB: IR/imon: add proper auto-repeat support
Simplified from version 1, in that hacks heisted from ati_remote2.c
aren't actually necessary, the real fix for too many repeats was
from setting too long a timer release value (200ms) on repeats in
mce mode -- this patch drops the release timeout to 33ms, matching
the input subsystem default input_dev->rep[REP_PERIOD].

Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-05-19 12:58:27 -03:00
Jarod Wilson
666a9ed897 V4L/DVB: IR/imon: minor change_protocol fixups
This is a follow-up to my prior patch implementing ir-core's
change_protocol functionality in the imon driver, which eliminates
a false warning when change_protocol is called without a specific
protocol selected yet (i.e., still IR_TYPE_UNKNOWN). It also removes
some extraneous blank lines getting spewn into dmesg.

Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-05-19 12:58:26 -03:00
Jarod Wilson
6718e8ad95 V4L/DVB: IR/imon: convert to ir-core protocol change handling
Drop the imon driver's internal protocol definitions in favor of using
those provided by ir-core. Should make ir-keytable Just Work for
switching protocol on the fly on the imon devices that support both the
native imon remotes and mce remotes.

The imon-no-pad-stabilize pseudo-protocol was dropped as a protocol, and
converted to a separate modprobe option (which it probably should have
been in the first place). On the TODO list is to convert this to an as yet
unwritten protocol-specific options framework.

While the mce remotes obviously map to IR_TYPE_RC6, I've yet to look at
what the actual ir signals from the native imon remotes are, so for the
moment, imon native ir is mapped to IR_TYPE_OTHER. Nailing it down more
accurately is also on the TODO list.

Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-05-19 12:58:24 -03:00
Mauro Carvalho Chehab
1f71baef3e V4L/DVB: irmon: Cleanup some warning noise
Driver is not properly initializing u64 constants on 32 bit systems:
drivers/media/IR/imon.c:301: warning: integer constant is too large for ‘long’ type
drivers/media/IR/imon.c:302: warning: integer constant is too large for ‘long’ type
drivers/media/IR/imon.c:304: warning: integer constant is too large for ‘long’ type
drivers/media/IR/imon.c:305: warning: integer constant is too large for ‘long’ type
drivers/media/IR/imon.c:308: warning: integer constant is too large for ‘long’ type
drivers/media/IR/imon.c:309: warning: integer constant is too large for ‘long’ type
drivers/media/IR/imon.c:310: warning: integer constant is too large for ‘long’ type

Fix also a few troubles at error printk handling:
drivers/media/IR/imon.c: In function ‘imon_init_intf0’:
drivers/media/IR/imon.c:1909: warning: ‘ret’ may be used uninitialized in this function
drivers/media/IR/imon.c: In function ‘imon_init_intf1’:
drivers/media/IR/imon.c:1989: warning: ‘ret’ may be used uninitialized in this function

Cc: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-05-19 12:57:44 -03:00
Jarod Wilson
21677cfc56 V4L/DVB: ir-core: add imon driver
This is a new driver for the SoundGraph iMON and Antec Veris IR/display
devices commonly found in many home theater pc cases and as after-market
case additions.

[mchehab@redhat.com: add KERN_CONT on line 2098 to shutup checkpatc.pl]

Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-05-19 12:57:42 -03:00