Add an optional feature of PPSAPI, kernel consumer support, which uses the
added hardpps() function.
Signed-off-by: NAlexander Gordeev <lasaine@lvk.cs.msu.su>
Acked-by: NRodolfo Giometti <giometti@linux.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

MONOTONIC_RAW clock timestamps are ideally suited for frequency
calculation and also fit well into the original NTP hardpps design.  Now
phase and frequency can be adjusted separately: the former based on
REALTIME clock and the latter based on MONOTONIC_RAW clock.

A new function getnstime_raw_and_real is added to timekeeping subsystem to
capture both timestamps at the same time and atomically.
Signed-off-by: NAlexander Gordeev <lasaine@lvk.cs.msu.su>
Acked-by: NJohn Stultz <johnstul@us.ibm.com>
Cc: Rodolfo Giometti <giometti@enneenne.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This commit adds hardpps() implementation based upon the original one from
the NTPv4 reference kernel code from David Mills.  However, it is highly
optimized towards very fast syncronization and maximum stickness to PPS
signal.  The typical error is less then a microsecond.

To make it sync faster I had to throw away exponential phase filter so
that the full phase offset is corrected immediately.  Then I also had to
throw away median phase filter because it gives a bigger error itself if
used without exponential filter.

Maybe we will find an appropriate filtering scheme in the future but it's
not necessary if the signal quality is ok.
Signed-off-by: NAlexander Gordeev <lasaine@lvk.cs.msu.su>
Acked-by: NJohn Stultz <johnstul@us.ibm.com>
Cc: Rodolfo Giometti <giometti@enneenne.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove the code that gatheres timestamp in pps_tty_dcd_change() in case
passed ts parameter is NULL because it never happens in the current code.
Fix comments as well.
Signed-off-by: NAlexander Gordeev <lasaine@lvk.cs.msu.su>
Acked-by: NRodolfo Giometti <giometti@linux.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Bitwise conjunction is distributive so we can simplify some conditions.
Signed-off-by: NAlexander Gordeev <lasaine@lvk.cs.msu.su>
Acked-by: NRodolfo Giometti <giometti@linux.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This way less overhead is involved when running production kernel.  If you
want to debug a pps client module please define DEBUG to enable the
checks.
Signed-off-by: NAlexander Gordeev <lasaine@lvk.cs.msu.su>
Acked-by: NRodolfo Giometti <giometti@linux.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Now pps_idr_lock is never used in interrupt context so we can replace
spin_lock_irq/spin_unlock_irq with plain spin_lock/spin_unlock. But
there is also a potential race condition when someone can steal an id
which was allocated by idr_pre_get before it is used. So convert spin
lock to mutex and protect the whole id generation process.
Signed-off-by: NAlexander Gordeev <lasaine@lvk.cs.msu.su>
Cc: Rodolfo Giometti <giometti@linux.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Since now idr is only used to manage char device id's and not used in
kernel API anymore it should be moved to pps.c.  This also makes it
possible to release id only at actual device freeing so nobody can
register a pps device with the same id while our device is not freed yet.
Signed-off-by: NAlexander Gordeev <lasaine@lvk.cs.msu.su>
Acked-by: NRodolfo Giometti <giometti@linux.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Since we now have direct pointers to struct pps_device everywhere it's
easy to use dev_* functions to print messages instead of plain printks.
Where dev_* cannot be used printks are converted to pr_*.
Signed-off-by: NAlexander Gordeev <lasaine@lvk.cs.msu.su>
Acked-by: NRodolfo Giometti <giometti@linux.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Using device index as a pointer needs some unnecessary work to be done
every time the pointer is needed (in irq handler for example).  Using a
direct pointer is much more easy (and safe as well).
Signed-off-by: NAlexander Gordeev <lasaine@lvk.cs.msu.su>
Acked-by: NRodolfo Giometti <giometti@linux.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a helper function to gather timestamps.  This way clients don't have
to duplicate it.
Signed-off-by: NAlexander Gordeev <lasaine@lvk.cs.msu.su>
Acked-by: NRodolfo Giometti <giometti@linux.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There was a race in PPS_FETCH ioctl handler when several processes want to
obtain PPS data simultaneously using sleeping PPS_FETCH.  They all sleep
most of the time in the system call.

With the old approach when the first process waiting on the pps queue is
waken up it makes new system call right away and zeroes pps->go.  So other
processes continue to sleep.  This is a clear race condition because of
the global 'go' variable.

With the new approach pps->last_ev holds some value increasing at each PPS
event.  PPS_FETCH ioctl handler saves current value to the local variable
at the very beginning so it can safely check that there is a new event by
just comparing both variables.
Signed-off-by: NAlexander Gordeev <lasaine@lvk.cs.msu.su>
Acked-by: NRodolfo Giometti <giometti@linux.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Move variable declarations where they are used in pps_cdev_ioctl.
Signed-off-by: NAlexander Gordeev <lasaine@lvk.cs.msu.su>
Acked-by: NRodolfo Giometti <giometti@linux.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Here are some very trivial fixes combined:

- add macro definitions to protect header file from including several times

- remove declaration for an unexistent array

- fix typos
Signed-off-by: NAlexander Gordeev <lasaine@lvk.cs.msu.su>
Acked-by: NRodolfo Giometti <giometti@linux.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 4be2c95d ("taskstats: pad taskstats netlink response for aligment
issues on ia64") added a null field to align the taskstats structure but
the discussion centered around ia64.  The issue exists on other platforms
with inefficient unaligned access and adding them piecemeal would be an
unmaintainable mess.

This patch uses Dave Miller's suggestion of using a combination of
CONFIG_64BIT && !CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS to determine
whether alignment is needed.

Note that this will cause breakage on those platforms with applications
like iotop which had hard-coded offsets into the packet to access the
taskstats structure.

The message seen on systems without the alignment fixes looks like: kernel
unaligned access to 0xe000023879dca9bc, ip=0xa000000100133d10

The addresses may vary but resolve to locations inside __delayacct_add_tsk.

iotop makes what I'd call unreasonable assumptions about the contents of a
netlink genetlink packet containing generic attributes.  They're typed and
have headers that specify value lengths, so the client can (should)
identify and skip the ones the client doesn't understand.

The kernel, as of version 2.6.36, presented a packet like so:
+--------------------------------+
| genlmsghdr - 4 bytes           |
+--------------------------------+
| NLA header - 4 bytes           | /* Aggregate header */
+-+------------------------------+
| | NLA header - 4 bytes         | /* PID header */
| +------------------------------+
| | pid/tgid   - 4 bytes         |
| +------------------------------+
| | NLA header - 4 bytes         | /* stats header */
| + -----------------------------+ <- oops. aligned on 4 byte boundary
| | struct taskstats - 328 bytes |
+-+------------------------------+

The iotop code expects that the kernel will behave as it did then,
assuming that the packet format is set in stone.  The format is set in
stone, but the packet offsets are not.  There's nothing in the packet
format that guarantees that the packet will be sent in exactly the same
way.  The attribute contents are set (or versioned) and the aggregate
contents are set but they can be anywhere in the packet.

The issue here isn't that an unaligned structure gets passed to userspace,
it's that the NLA infrastructure has something of a weakness: The 4 byte
attribute header may force the payload to be unaligned.  The taskstats
structure is created at an unaligned location and then 64-bit values are
operated on inside the kernel, so the unaligned access warnings gets
spewed everywhere.

It's possible to use the unaligned access API to operate on the structure
in the kernel but it seems like a wasted effort to work around userspace
code that isn't following the packet format.  Any new additions would also
need the be worked around.  It's a maintenance nightmare.

The conclusion of the earlier discussion seemed to be "ok fine, if we have
to break it, don't break it on arches that don't have the problem." Dave
pointed out that the unaligned access problem doesn't only exist on ia64,
but also on other 64-bit arches that don't have efficient unaligned access
and it should be fixed there as well.  The committed version of the patch
and this addition keep with the conclusion of that discussion not to break
it unnecessarily, which the pid padding and the packet padding fixes did
do.  x86_64 and powerpc don't suffer this problem so they shouldn't suffer
the solution.  Other 64-bit architectures do and will, though.
Signed-off-by: NJeff Mahoney <jeffm@suse.com>
Reported-by: NDavid S. Miller <davem@davemloft.net>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Cc: Dan Carpenter <error27@gmail.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Florian Mickler <florian@mickler.org>
Cc: Guillaume Chazarain <guichaz@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Creates a new "Near Field Communication" subsystem in drivers/nfc.
http://en.wikipedia.org/wiki/Near_Field_Communication is useful ;)

This is a driver for the pn544 NFC device. The driver transfers
ETSI messages between the device and the user space.
Signed-off-by: NMatti J. Aaltonen <matti.j.aaltonen@nokia.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently on 64-bit arch the user_namespace is 2096 and when being
kmalloc-ed it resides on a 4k slab wasting 2003 bytes.

If we allocate a separate cache for it and reduce the hash size from 128
to 64 chains the packaging becomes *much* better - the struct is 1072
bytes and the hole between is 98 bytes.

[akpm@linux-foundation.org: s/__initcall/module_init/]
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Acked-by: NSerge E. Hallyn <serge@hallyn.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

ctl_unnumbered.txt have been removed in Documentation directory so just
also remove this invalid comments

[akpm@linux-foundation.org: fix Documentation/sysctl/00-INDEX, per Dave]
Signed-off-by: NJovi Zhang <bookjovi@gmail.com>
Cc: Dave Young <hidave.darkstar@gmail.com>
Acked-by: NWANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NJovi Zhang <bookjovi@gmail.com>
Acked-by: NWANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In fsl_rio_dbell_handler() the code currently simply acknowledges the QFI
queue full interrupt, but does nothing to resolve the queue full
condition.  Instead, it jumps to the end of the isr.  When a queue full
condition occurs, the isr is then re-entered immediately and continually,
forever.

The fix is to just fall through and read out current doorbell entries.
Signed-off-by: NThomas Taranowski <tom@baringforge.com>
Cc: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Cc: Micha Nelissen <micha@neli.hopto.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add new sRIO switch device IDs and enable a basic support for them.
Signed-off-by: NAlexandre Bounine <alexandre.bounine@idt.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Cc: Micha Nelissen <micha@neli.hopto.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Change the way how switchid value is set.  Local counter variable does not
provide unified way to identify switch devices in a system with multiple
processors.  Using local counter leads to the situation when the same RIO
switch has different switch ID for each processor.  Replacing local
counter with unique portion of the Component Tag provides unified
reference to the switch by every processor in the system.
Signed-off-by: NAlexandre Bounine <alexandre.bounine@idt.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Cc: Micha Nelissen <micha@neli.hopto.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add setting links between rio_dev objects into the discovery process.
This needed to report device connections on agent (non-host) processors
that perform RIO discovery.  Originally, these links have been introduced
for enumerating host only to support error management.
Signed-off-by: NAlexandre Bounine <alexandre.bounine@idt.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Cc: Micha Nelissen <micha@neli.hopto.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add definition of the unique device identifier field in the component tag.
 RIO_CTAG_UDEVID does not take all 32 bits of the component tag value to
allow future extensions to the component tag use.

Selected size of the RIO_CTAG_UDEVID field (17 bits) is sufficient to
accommodate maximum number of endpoints in large RIO network (16-bit id)
plus switches.
Signed-off-by: NAlexandre Bounine <alexandre.bounine@idt.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Cc: Micha Nelissen <micha@neli.hopto.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Convert RIO switches device structures (rio_dev + rio_switch) into a
single allocation unit.

This change is based on the fact that RIO switches are using common RIO
device objects anyway.  Allocating RIO switch objects as RIO devices with
added space for switch information simplifies handling of RIO switch
devices.
Signed-off-by: NAlexandre Bounine <alexandre.bounine@idt.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Cc: Micha Nelissen <micha@neli.hopto.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Change code to use one storage location common for switches and endpoints.
This eliminates unnecessary device type checks during basic access
operations.  Logic that assigns destid to RIO devices stays unchanged - as
before, switches use an associated destid because they do not have their
own.
Signed-off-by: NAlexandre Bounine <alexandre.bounine@idt.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Cc: Micha Nelissen <micha@neli.hopto.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 66fa12c5 ("ieee1394: remove the old IEEE 1394 driver stack")
eliminated the only user of cdev_index().  So it can be removed too.
Signed-off-by: NNamhyung Kim <namhyung@gmail.com>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 34aacb29 ("procfs: Use generic_file_llseek in /proc/kcore") broke
seeking on /proc/kcore.  This changes it back to use default_llseek in
order to restore the original behavior.

The problem with generic_file_llseek is that it only allows seeks up to
inode->i_sb->s_maxbytes, which is 2GB-1 on procfs, where the memory file
offset values in the /proc/kcore PT_LOAD segments may exceed or start
beyond that offset value.

A similar revert was made for /proc/vmcore.
Signed-off-by: NDave Anderson <anderson@redhat.com>
Acked-by: NFrederic Weisbecker <fweisbec@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Filename is supposed to match procfile name for random junk.

Add __init while I'm at it.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

For the common case where a proc entry is being removed and nobody is in
the process of using it, save a LOCK/UNLOCK pair.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a PageSlab() check before adding the _mapcount value to /kpagecount.
page->_mapcount is in a union with the SLAB structure so for pages
controlled by SLAB, page_mapcount() returns nonsense.
Signed-off-by: NPetr Holasek <pholasek@redhat.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

single_open()'s third argument is for copying into seq_file->private.  Use
that, rather than open-coding it.
Signed-off-by: NJovi Zhang <bookjovi@gmail.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
Acked-by: NAlexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

- ->low_ino is write-once field -- reading it under locks is unnecessary.

- /proc/$PID stuff never reaches pde_put()/free_proc_entry() --
   PROC_DYNAMIC_FIRST check never triggers.

- in proc_get_inode(), inode number always matches proc dir entry, so
  save one parameter.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

For string without format specifiers, use seq_puts().
For seq_printf("\n"), use seq_putc('\n').

   text	   data	    bss	    dec	    hex	filename
  61866	    488	    112	  62466	   f402	fs/proc/proc.o
  61729	    488	    112	  62329	   f379	fs/proc/proc.o
  ----------------------------------------------------
  			   -139
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

/proc/*/statm code needlessly truncates data from unsigned long to int.
One needs only 8+ TB of RAM to make truncation visible.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: NWANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Use temporary lr for struct latency_record for improved readability and
fewer columns used.  Removed trailing space from output.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NJoe Perches <joe@perches.com>
Cc: Jiri Kosina <trivial@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The 'ns' cgroup is considered deprecated. Change the cgroup subsystem
used in the examples of the cgroup documentation from 'ns' to 'blkio'.
Signed-off-by: NTrevor Woerner <twoerner@gmail.com>
Acked-by: NLi Zefan <lizf@cn.fujitsu.com>
Acked-by: NPaul Menage <menage@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Show how to install the "toggle wordwrap" extension in thunderbird.
Signed-off-by: NRob Landley <rlandley@parallels.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NLasse Collin <lasse.collin@tukaani.org>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

A call to va_start() must always be followed by a call to va_end() in the
same function.  In fs/reiserfs/prints.c::print_block() this is not always
the case.  If 'bh' is NULL we'll return without calling va_end().

One could add a call to va_end() before the 'return' statement, but it's
nicer to just move the call to va_start() after the test for 'bh' being
NULL.
Signed-off-by: NJesper Juhl <jj@chaosbits.net>
Acked-by: NEdward Shishkin <edward.shishkin@gmail.com>
Cc: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>