Commit Graph

26 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
Gustavo F. Padovan 4f7ac1814e Bluetooth: Fix wrong packet type count increment
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2010-05-10 09:28:45 +02:00
Marcel Holtmann c13854cef4 Bluetooth: Convert controller hdev->type to hdev->bus
The hdev->type is misnamed and should be actually hdev->bus instead. So
convert it now.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2010-02-27 14:05:38 +01:00
Marcel Holtmann fed4c2508b Bluetooth: Fix miscdev ops owner for virtual driver
The /dev/vhci ops don't refer to the module and so it is possible to
unload the module while the file descriptor is in use. This was an
accidental removal after the cleanup.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-12-03 19:34:19 +01:00
Marcel Holtmann 329ab1b3e6 Bluetooth: Remove unused global minor variable
After the removal of the module parameter for setting the minor number,
this variable became unused. So just remove it.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-12-03 19:34:18 +01:00
Thomas Gleixner 5990108cfc Bluetooth: Remove stub ioctl in hci_vhci
Remove the empty ioctl which just returns -EINVAL. vfs_ioctl() will
return -ENOTTY instead, but I doubt that any application will notice
the difference :)

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-12-03 19:34:18 +01:00
Alexey Dobriyan 405f55712d headers: smp_lock.h redux
* Remove smp_lock.h from files which don't need it (including some headers!)
* Add smp_lock.h to files which do need it
* Make smp_lock.h include conditional in hardirq.h
  It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT

  This will make hardirq.h inclusion cheaper for every PREEMPT=n config
  (which includes allmodconfig/allyesconfig, BTW)

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-12 12:22:34 -07:00
Marcel Holtmann 092b85853b Bluetooth: Remove unused and unneeded support in virtual driver
The virtual driver implements fasync and ioctl support, but it is not used
and unneeded due to its constraints via the Bluetooth core layer. So too
just make the driver simpler, remove support for both of them.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-06-08 14:50:01 +02:00
Marcel Holtmann 3857abc622 Bluetooth: Remove BKL from open callback of virtual driver
The BKL push down added some BKL into the open callback of the virtual
driver. The driver is really simple and need no such locking and so just
remove it.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-06-08 14:50:01 +02:00
Marcel Holtmann 4db7589f3d Bluetooth: Use wait_event_interruptible for virtual driver
The virtual driver still uses a home grown way of waiting for events and
so just replace it with wait_event_interruptible. And while at it remove
the useless access_ok() checks.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-06-08 14:50:01 +02:00
Marcel Holtmann ac28494c51 Bluetooth: Use only MISC_DYNAMIC_MINOR for virtual driver
Allowing to specify a specific misc minor number for the virtual driver
is pretty much useless and nobody is using this feature. So just remove
it and use MISC_DYNAMIC_MINOR all the time.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2009-06-08 14:50:01 +02:00
Marcel Holtmann a418b893a6 Bluetooth: Enable per-module dynamic debug messages
With the introduction of CONFIG_DYNAMIC_PRINTK_DEBUG it is possible to
allow debugging without having to recompile the kernel. This patch turns
all BT_DBG() calls into pr_debug() to support dynamic debug messages.

As a side effect all CONFIG_BT_*_DEBUG statements are now removed and
some broken debug entries have been fixed.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2008-11-30 12:17:28 +01:00
Marcel Holtmann 63fbd24e51 [Bluetooth] Consolidate maintainers information
The Bluetooth entries for the MAINTAINERS file are a little bit too
much. Consolidate them into two entries. One for Bluetooth drivers and
another one for the Bluetooth subsystem.

Also the MODULE_AUTHOR should indicate the current maintainer of the
module and actually not the original author. Fix all Bluetooth modules
to provide current maintainer information.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2008-08-18 13:23:53 +02:00
Jonathan Corbet dbfb2df7e9 Bluetooth VHCI: fasync BKL pushdown
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2008-07-02 15:06:28 -06:00
Arnd Bergmann 8324af6ddd bluetooth-vhci: BKL pushdown
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2008-06-20 14:05:55 -06:00
Robert P. J. Day 924f0e4a06 [Bluetooth] Remove the redundant non-seekable llseek method
Remove the llseek method given that the open method already calls
nonseekable_open().

Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2007-07-11 06:53:45 +02:00
Arjan van de Ven 2b8693c061 [PATCH] mark struct file_operations const 3
Many struct file_operations in the kernel can be "const".  Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data.  In addition it'll catch accidental writes at compile time to
these shared resources.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:45 -08:00
Marcel Holtmann 0ac53939a0 [Bluetooth] Add HCI device identifier for SDIO cards
This patch assigns the next free HCI device identifier to Bluetooth
devices based on the SDIO interface.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2006-09-28 18:01:28 -07:00
Marcel Holtmann 9c724357f4 [Bluetooth] Code cleanup of the drivers source code
This patch is an attempt to cleanup the drivers source code to make all
Bluetooth drivers look more unique.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2006-09-28 18:01:27 -07:00
Marcel Holtmann 27d3528425 [Bluetooth] Add platform device for virtual and serial devices
This patch adds a generic Bluetooth platform device that can be used
as parent device by virtual and serial devices.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2006-07-03 19:54:00 -07:00
Jörn Engel 6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Deepak Saxena 089b1dbbde [PATCH] bluetooth: kmalloc + memset -> kzalloc conversion
Signed-off-by: Deepak Saxena <dsaxena@plexity.net>
Cc: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 07:54:00 -08:00
Marcel Holtmann 0d48d93947 [Bluetooth]: Move packet type into the SKB control buffer
This patch moves the usage of packet type into the SKB control
buffer. After this patch it is now possible to shrink the sk_buff
structure and redefine its pkt_type.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29 15:55:13 -07:00
Marcel Holtmann 4aa769b997 [Bluetooth]: Update and cleanup of the virtual HCI driver
This patch cleans up the virtual HCI driver. It also adds support for
the dynamic minor device number allocation.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29 15:54:42 -07:00
David S. Miller b03efcfb21 [NET]: Transform skb_queue_len() binary tests into skb_queue_empty()
This is part of the grand scheme to eliminate the qlen
member of skb_queue_head, and subsequently remove the
'list' member of sk_buff.

Most users of skb_queue_len() want to know if the queue is
empty or not, and that's trivially done with skb_queue_empty()
which doesn't use the skb_queue_head->qlen member and instead
uses the queue list emptyness as the test.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-08 14:57:23 -07:00
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00