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  1. 14 8月, 2012 2 次提交
  3. 29 3月, 2012 1 次提交
  5. 29 12月, 2010 1 次提交
  7. 21 10月, 2010 1 次提交
  9. 19 10月, 2010 1 次提交
    • A
      dvb-core: kill the big kernel lock · 72024f1e
      由 Arnd Bergmann 提交于 
      The dvb core only uses the big kernel lock in the open
and ioctl functions, which means it can be replaced with
a dvb specific mutex. Fortunately, all the ioctl functions
go through dvb_usercopy, so we can move the serialization
in there.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: linux-media@vger.kernel.org
      72024f1e
  11. 15 10月, 2010 1 次提交
    • A
      llseek: automatically add .llseek fop · 6038f373
      由 Arnd Bergmann 提交于 
      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: NArnd Bergmann <arnd@arndb.de>
Cc: Julia Lawall <julia@diku.dk>
Cc: Christoph Hellwig <hch@infradead.org>
      6038f373
  13. 03 8月, 2010 1 次提交
    • J
      V4L/DVB: DVB: fix dvr node refcounting · 1c488ea9
      由 Jiri Slaby 提交于 
      In dvb_dvr_release, there is a test dvbdev->users==-1, but users are
never negative. This error results in hung tasks:
  task                        PC stack   pid father
bash          D ffffffffa000c948     0  3264   3170 0x00000000
 ffff88003aec5ce8 0000000000000086 0000000000011f80 0000000000011f80
 ffff88003aec5fd8 ffff88003aec5fd8 ffff88003b848670 0000000000011f80
 ffff88003aec5fd8 0000000000011f80 ffff88003e02a030 ffff88003b848670
Call Trace:
 [<ffffffff813dd4a5>] dvb_dmxdev_release+0xc5/0x130
 [<ffffffff8107b750>] ? autoremove_wake_function+0x0/0x40
 [<ffffffffa00013a2>] dvb_usb_adapter_dvb_exit+0x42/0x70 [dvb_usb]
 [<ffffffffa0000525>] dvb_usb_exit+0x55/0xd0 [dvb_usb]
 [<ffffffffa00005ee>] dvb_usb_device_exit+0x4e/0x70 [dvb_usb]
 [<ffffffffa000a065>] af9015_usb_device_exit+0x55/0x60 [dvb_usb_af9015]
 [<ffffffff813a3f05>] usb_unbind_interface+0x55/0x1a0
 [<ffffffff81316000>] __device_release_driver+0x70/0xe0
...

So check against 1 there instead.

BTW why's the TODO there? Adding TODOs to the code without
descriptions is like adding nothing.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>
      1c488ea9
  15. 17 5月, 2010 1 次提交
  17. 08 2月, 2010 1 次提交
  19. 05 10月, 2009 1 次提交
  21. 02 10月, 2009 1 次提交
  23. 12 9月, 2009 1 次提交
    • A
      V4L/DVB (12275): Add two new ioctls: DMX_ADD_PID and DMX_REMOVE_PID · 1cb662a3
      由 Andreas Oberritter 提交于 
      DMX_ADD_PID allows to add multiple PIDs to a transport stream filter
previously set up with DMX_SET_PES_FILTER and output=DMX_OUT_TSDEMUX_TAP.

DMX_REMOVE_PID is used to drop a PID from a filter.

These ioctls are to be used by readers of /dev/dvb/adapterX/demuxY. They
may be called at any time, i.e. before or after the first filter on the
shared file descriptor was started.

They make it possible to record multiple services without the need to de-
or re-multiplex TS packets.

To accomplish this, dmxdev_filter->feed.ts has been converted to a list
of struct dmxdev_feeds, each containing a PID value and a pointer to a
struct dmx_ts_feed.
Signed-off-by: NAndreas Oberritter <obi@linuxtv.org>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>
      1cb662a3
  25. 17 6月, 2009 1 次提交
  27. 30 3月, 2009 1 次提交
  29. 17 2月, 2009 1 次提交
    • M
      V4L/DVB (10572): Revert commit dda06a8e · 28100165
      由 Mauro Carvalho Chehab 提交于 
      On Mon, 02 Feb 2009, Hartmut wrote:

This change set is wrong. The affected functions cannot be called from
an interrupt context, because they may process large buffers. In this
case, interrupts are disabled for a long time. Functions, like
dvb_dmx_swfilter_packets(), could be called only from a tasklet.

This change set does hide some strong design bugs in dm1105.c and
au0828-dvb.c.

Please revert this change set and do fix the bugs in dm1105.c and
au0828-dvb.c (and other files).

On Sun, 15 Feb 2009, Oliver Endriss wrote:

This changeset _must_ be reverted! It breaks all kernels since 2.6.27
for applications which use DVB and require a low interrupt latency.

It is a very bad idea to call the demuxer to process data buffers with
interrupts disabled!

On Mon, 16 Feb 2009, Trent Piepho wrote:

I agree, this is bad.  The demuxer is far too much work to be done with
IRQs off.  IMHO, even doing it under a spin-lock is excessive.  It should
be a mutex.  Drivers should use a work-queue to feed the demuxer.

Thank you for testing this changeset and discovering the issues on it.

Cc: Trent Piepho <xyzzy@speakeasy.org>
Cc: Hartmut <e9hack@googlemail.com>
Cc: Oliver Endriss <o.endriss@gmx.de>
Cc: Andreas Oberritter <obi@linuxtv.org>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>
      28100165
  31. 05 10月, 2008 1 次提交
  33. 04 9月, 2008 1 次提交
  35. 20 7月, 2008 1 次提交
  37. 25 4月, 2008 5 次提交
  39. 10 10月, 2007 1 次提交
  41. 19 7月, 2007 1 次提交
  43. 28 4月, 2007 1 次提交
  45. 27 3月, 2007 1 次提交
  47. 15 2月, 2007 1 次提交
    • T
      [PATCH] remove many unneeded #includes of sched.h · cd354f1a
      由 Tim Schmielau 提交于 
      After Al Viro (finally) succeeded in removing the sched.h #include in module.h
recently, it makes sense again to remove other superfluous sched.h includes.
There are quite a lot of files which include it but don't actually need
anything defined in there.  Presumably these includes were once needed for
macros that used to live in sched.h, but moved to other header files in the
course of cleaning it up.

To ease the pain, this time I did not fiddle with any header files and only
removed #includes from .c-files, which tend to cause less trouble.

Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha,
arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig,
allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all
configs in arch/arm/configs on arm.  I also checked that no new warnings were
introduced by the patch (actually, some warnings are removed that were emitted
by unnecessarily included header files).
Signed-off-by: NTim Schmielau <tim@physik3.uni-rostock.de>
Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      cd354f1a
  49. 25 6月, 2006 1 次提交
  51. 02 4月, 2006 1 次提交
  53. 22 3月, 2006 4 次提交
  55. 27 2月, 2006 1 次提交
  57. 07 2月, 2006 1 次提交
  59. 13 12月, 2005 1 次提交
  61. 10 9月, 2005 2 次提交