Commit Graph

24 Commits

Author SHA1 Message Date
Linus Torvalds 092e0e7e52 Merge branch 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl
* '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
2010-10-22 10:52:56 -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
Arnd Bergmann 613655fa39 drivers: autoconvert trivial BKL users to private mutex
All these files use the big kernel lock in a trivial
way to serialize their private file operations,
typically resulting from an earlier semi-automatic
pushdown from VFS.

None of these drivers appears to want to lock against
other code, and they all use the BKL as the top-level
lock in their file operations, meaning that there
is no lock-order inversion problem.

Consequently, we can remove the BKL completely,
replacing it with a per-file mutex in every case.
Using a scripted approach means we can avoid
typos.

These drivers do not seem to be under active
maintainance from my brief investigation. Apologies
to those maintainers that I have missed.

file=$1
name=$2
if grep -q lock_kernel ${file} ; then
    if grep -q 'include.*linux.mutex.h' ${file} ; then
            sed -i '/include.*<linux\/smp_lock.h>/d' ${file}
    else
            sed -i 's/include.*<linux\/smp_lock.h>.*$/include <linux\/mutex.h>/g' ${file}
    fi
    sed -i ${file} \
        -e "/^#include.*linux.mutex.h/,$ {
                1,/^\(static\|int\|long\)/ {
                     /^\(static\|int\|long\)/istatic DEFINE_MUTEX(${name}_mutex);

} }"  \
    -e "s/\(un\)*lock_kernel\>[ ]*()/mutex_\1lock(\&${name}_mutex)/g" \
    -e '/[      ]*cycle_kernel_lock();/d'
else
    sed -i -e '/include.*\<smp_lock.h\>/d' ${file}  \
                -e '/cycle_kernel_lock()/d'
fi

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2010-10-05 15:01:04 +02:00
Grant Likely f1ca09b2b5 of: Fix missing includes
This patch fixes missing includes from a number of .c files because
the code (wrongfully) depended on prom.h including them.  The include
of linux/of_address.h was removed in microblaze prom.h in commit
"of/address: Clean up function declarations" (sha1 id 22ae782f8), but
not fixed in some callers.  This patch fixes them up.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: Michal Simek <monstr@monstr.eu>
2010-08-16 23:44:49 -06:00
Grant Likely 2dc1158137 of/device: Replace struct of_device with struct platform_device
of_device is just an alias for platform_device, so remove it entirely.  Also
replace to_of_device() with to_platform_device() and update comment blocks.

This patch was initially generated from the following semantic patch, and then
edited by hand to pick up the bits that coccinelle didn't catch.

@@
@@
-struct of_device
+struct platform_device

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Reviewed-by: David S. Miller <davem@davemloft.net>
2010-08-06 09:25:50 -06:00
Grant Likely 4018294b53 of: Remove duplicate fields from of_platform_driver
.name, .match_table and .owner are duplicated in both of_platform_driver
and device_driver.  This patch is a removes the extra copies from struct
of_platform_driver and converts all users to the device_driver members.

This patch is a pretty mechanical change.  The usage model doesn't change
and if any drivers have been missed, or if anything has been fixed up
incorrectly, then it will fail with a compile time error, and the fixup
will be trivial.  This patch looks big and scary because it touches so
many files, but it should be pretty safe.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Sean MacLennan <smaclennan@pikatech.com>
2010-05-22 00:10:40 -06:00
Grant Likely 61c7a080a5 of: Always use 'struct device.of_node' to get device node pointer.
The following structure elements duplicate the information in
'struct device.of_node' and so are being eliminated.  This patch
makes all readers of these elements use device.of_node instead.

(struct of_device *)->node
(struct dev_archdata *)->prom_node (sparc)
(struct dev_archdata *)->of_node (powerpc & microblaze)

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2010-05-18 16:10:44 -06:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Alexey Dobriyan 828c09509b const: constify remaining file_operations
[akpm@linux-foundation.org: fix KVM]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-01 16:11:11 -07:00
Greg Kroah-Hartman 09a35ce00f xilinx_hwicap: remove improper wording in license statement
GPLv2 doesn't allow additional restrictions to be imposed on any
code, so this wording needs to be removed from these files.

Signed-off-by: Stephen Neuendorffer <stephen.neuendorffer@xilinx.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-12-17 11:23:07 -08:00
Grant Likely a108096878 powerpc/virtex: fix various format/casting printk mismatches
Various printk format string in code used by the Xilinx Virtex platform
are not 32-bit/64-bit safe.  Add correct casting to fix the bugs.

Reported-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2008-11-14 09:59:48 -07:00
Greg Kroah-Hartman 03457cd455 device create: char: convert device_create_drvdata to device_create
Now that device_create() has been audited, rename things back to the
original call to be sane.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-10-16 09:24:42 -07:00
Adrian Bunk 7a8fc9b248 removed unused #include <linux/version.h>'s
This patch lets the files using linux/version.h match the files that
#include it.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-08-23 12:14:12 -07:00
Huang Weiyi b09c3e3f17 removed unused #include <version.h>
The drivers below do not use LINUX_VERSION_CODE nor KERNEL_VERSION.
  drivers/char/pcmcia/ipwireless/tty.c
  drivers/char/synclink_gt.c
  drivers/char/xilinx_hwicap/xilinx_hwicap.c

This patch removes the said #include <version.h>.

Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-08-16 17:21:58 -07:00
Huang Weiyi 43de804df8 char/xilinx_hwicap/xilinx_hwicap.c: Removed duplicated include
Removed duplicated include file <linux/version.h> in
char/xilinx_hwicap/xilinx_hwicap.c.

Signed-off-by: Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 09:23:31 -07:00
Greg Kroah-Hartman 47aa5793f7 device create: char: convert device_create to device_create_drvdata
device_create() is race-prone, so use the race-free
device_create_drvdata() instead as device_create() is going away.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-21 21:54:41 -07:00
Jonathan Corbet f4943db14f xilinx icap: BKL pushdown
Add explicit lock_kernel() calls to hwicap_open() even though the existing
locking looks adequate.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2008-06-20 14:05:51 -06:00
Kumar Gala b17b8181c9 [POWERPC] Xilinx: Fix compile warnings
arch/powerpc/sysdev/xilinx_intc.c: In function 'xilinx_intc_init':
arch/powerpc/sysdev/xilinx_intc.c:111: warning: format '%08X' expects type 'unsigned int', but argument 2 has type 'resource_size_t'
drivers/char/xilinx_hwicap/xilinx_hwicap.c: In function 'hwicap_setup':
drivers/char/xilinx_hwicap/xilinx_hwicap.c:626: warning: cast to pointer from integer of different size
drivers/char/xilinx_hwicap/xilinx_hwicap.c:646: warning: format '%x' expects type 'unsigned int', but argument 6 has type 'resource_size_t'

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-05-01 23:09:42 -05:00
Adrian Bunk 2fd53e02be [POWERPC] char/xilinx_hwicap/ section fix
This patch fixes the following build error:

<--  snip  -->

...
  CC [M]  drivers/char/xilinx_hwicap/xilinx_hwicap.o
...
/home/bunk/linux/kernel-2.6/git/linux-2.6/drivers/char/xilinx_hwicap/xilinx_hwicap.c:806: error: hwicap_of_match causes a section type conflict
/home/bunk/linux/kernel-2.6/git/linux-2.6/drivers/char/xilinx_hwicap/xilinx_hwicap.c:806: error: hwicap_of_match causes a section type conflict
make[4]: *** [drivers/char/xilinx_hwicap/xilinx_hwicap.o] Error 1

<--  snip  -->

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-04-24 20:58:02 +10:00
Stephen Neuendorffer ac64673449 [POWERPC] Xilinx: hwicap: Use fixed device major.
Major 259 has been assigned by lanana.  Use it.  Also, publish
/dev/icap[0-k] as the device entries, and register platform devices
named 'icap' to be consistent.

Signed-off-by: Stephen Neuendorffer <stephen.neuendorffer@xilinx.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2008-03-26 07:27:31 -05:00
Stephen Neuendorffer 4c58f8fe2e [POWERPC] Xilinx: hwicap: Verify sync before reading idcode.
It appears that in some cases, the sync word might not be recognized
by the hardware correctly.  If this happens, then attempting to read
from the port results in an unrecoverable error because of the design
of the FPGA core.  This patch updates the code to check the status of
the device before reading the IDCODE, in order to avoid entering this
unrecoverable state.  This patch also adds additional NOOP commands
into the sychronization sequence, which appears to be necessary to
avoid the condition on some hardware.

Signed-off-by: Stephen Neuendorffer <stephen.neuendorffer@xilinx.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2008-03-26 07:27:21 -05:00
Stephen Neuendorffer 6b06fdbaf9 [POWERPC] Xilinx: hwicap: Refactor status handling code.
Both the buffer-based and fifo-based icap cores have a status
register.  Previously, this was only used internally to check whether
transactions have completed.  However, the status can be useful to the
main driver as well.  This patch exposes these status functions to the
main driver along with some masks for the differnet bits.

Signed-off-by: Stephen Neuendorffer <stephen.neuendorffer@xilinx.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2008-03-26 07:27:11 -05:00
Stephen Neuendorffer f62f2fdd9c [POWERPC] Xilinx: hwicap cleanup
This fixes various items pointed out during a review of the hwicap driver.
Primarily, reversed memcpy calls, re-entrancy issues, and mutex conversion
have been addressed.  There are also fixes to comments to use the kerneldoc
format, as well as some sparse annotations.

Signed-off-by: Stephen Neuendorffer <stephen.neuendorffer@xilinx.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2008-02-28 10:38:33 -06:00
Stephen Neuendorffer ef141a0bb0 [POWERPC] Xilinx: hwicap driver
This includes code for new fifo-based xps_hwicap in addition to the
older opb_hwicap, which has a significantly different interface.  The
common code between the two drivers is largely shared.

Significant differences exists between this driver and what is
supported in the EDK drivers.  In particular, most of the
architecture-specific code for reconfiguring individual FPGA resources
has been removed.  This functionality is likely better provided in a
user-space support library.  In addition, read and write access is
supported.  In addition, although the xps_hwicap cores support
interrupt-driver mode, this driver only supports polled operation, in
order to make the code simpler, and since the interrupt processing
overhead is likely to slow down the throughput under Linux.

Signed-off-by: Stephen Neuendorffer <stephen.neuendorffer@xilinx.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2008-02-06 10:23:52 -07:00