The cld.h file contains the definition of the upcall format to talk
with nfsdcld. When I added the file though, I neglected to add it
to the headers-y target, so make headers_install wasn't installing it.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Commit 18a4d0a2 ("[SCSI] Handle disk devices which can not process
medium access commands") introduced a bug in which we would attempt to
dereference the scsi driver even when the device had no ULD attached.

Ensure that a driver is registered and make the driver accessor function
more resilient to errors during device discovery.
Reported-by: NElric Fu <elricfu1@gmail.com>
Reported-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

GCC's NULL is actually __null, which allows detecting some questionable
NULL usage and warn about it.  Moreover each platform/compiler should
have its own stddef.h anyway (which is different from linux/stddef.h).

So there's no good reason to leak kernel's NULL to userspace and
override what the compiler provides.
Signed-off-by: NLuboš Luňák <l.lunak@suse.cz>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The AMBA bus regulator support is being used to model on/off switches
for power domains which isn't terribly idiomatic for modern kernels with
the generic power domain code and creates integration problems on platforms
which don't use regulators for their power domains as it's hard to tell
the difference between a regulator that is needed but failed to be provided
and one that isn't supposed to be there (though DT does make that easier).

Platforms that wish to use the regulator API to manage their power domains
can indirect via the power domain interface.

This feature is only used with the vape supply of the db8500 PRCMU
driver which supplies the UARTs and MMC controllers, none of which have
support for managing vcore at runtime in mainline (only pl022 SPI
controller does).  Update that supply to have an always_on constraint
until the power domain support for the system is updated so that it is
enabled for these users, this is likely to have no impact on practical
systems as probably at least one of these devices will be active and
cause AMBA to hold the supply on anyway.
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Tested-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Using IS_ENABLED() within C (vs.  within CPP #if statements) in its
current form requires us to actually define every possible bool/tristate
Kconfig option twice (__enabled_* and __enabled_*_MODULE variants).

This results in a huge autoconf.h file, on the order of 16k lines for a
x86_64 defconfig.

Fixing IS_ENABLED to be able to work on the smaller subset of just
things that we really have defined is step one to fixing this.  Which
means it has to not choke when fed non-enabled options, such as:

  include/linux/netdevice.h:964:1: warning: "__enabled_CONFIG_FCOE_MODULE" is not defined [-Wundef]

The original prototype of how to implement a C and preprocessor
compatible way of doing this came from the Google+ user "comex ." in
response to Linus' crowdsourcing challenge for a possible improvement on
his earlier C specific solution:

	#define config_enabled(x)       (__stringify(x)[0] == '1')

In this implementation, I've chosen variable names that hopefully make
how it works more understandable.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Use the ISO C standard compliant form instead of the gcc extension in the
interface definition.
Reported-by: NShachar Sharon <ssnail@gmail.com>
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>

this patch removes the pointer of uint64_t *edid. it should be just
a uint64_t.
Signed-off-by: NInki Dae <inki.dae@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>

This patch replaces the old global setting of irq_virq_count that is only
used by the NOMAP mapping and instead uses a revmap_data property so that
the maximum NOMAP allocation can be set per NOMAP irq_domain.

There is exactly one user of irq_virq_count in-tree right now: PS3.
Also, irq_virq_count is only useful for the NOMAP mapping.  So,
instead of having a single global irq_virq_count values, this change
drops it entirely and added a max_irq argument to irq_domain_add_nomap().
That makes it a property of an individual nomap irq domain instead of
a global system settting.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Tested-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>

We've been adding new mappings, but not destroying old mappings.
This can lead to a page leak as pages are pinned using
get_user_pages, but only unpinned with put_page if they still
exist in the memslots list on vm shutdown.  A memslot that is
destroyed while an iommu domain is enabled for the guest will
therefore result in an elevated page reference count that is
never cleared.

Additionally, without this fix, the iommu is only programmed
with the first translation for a gpa.  This can result in
peer-to-peer errors if a mapping is destroyed and replaced by a
new mapping at the same gpa as the iommu will still be pointing
to the original, pinned memory address.
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

Marc Merlin reported many order-1 allocations failures in TX path on its
wireless setup, that dont make any sense with MTU=1500 network, and non
SG capable hardware.

After investigation, it turns out TCP uses sk_stream_alloc_skb() and
used as a convention skb_tailroom(skb) to know how many bytes of data
payload could be put in this skb (for non SG capable devices)

Note : these skb used kmalloc-4096 (MTU=1500 + MAX_HEADER +
sizeof(struct skb_shared_info) being above 2048)

Later, mac80211 layer need to add some bytes at the tail of skb
(IEEE80211_ENCRYPT_TAILROOM = 18 bytes) and since no more tailroom is
available has to call pskb_expand_head() and request order-1
allocations.

This patch changes sk_stream_alloc_skb() so that only
sk->sk_prot->max_header bytes of headroom are reserved, and use a new
skb field, avail_size to hold the data payload limit.

This way, order-0 allocations done by TCP stack can leave more than 2 KB
of tailroom and no more allocation is performed in mac80211 layer (or
any layer needing some tailroom)

avail_size is unioned with mark/dropcount, since mark will be set later
in IP stack for output packets. Therefore, skb size is unchanged.
Reported-by: NMarc MERLIN <marc@merlins.org>
Tested-by: NMarc MERLIN <marc@merlins.org>
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix build warnings by providing a struct stub since no fields of
the struct are used:

include/linux/vgaarb.h:66:9: warning: 'struct pci_dev' declared inside parameter list
include/linux/vgaarb.h:66:9: warning: its scope is only this definition or declaration, which is probably not what you want
include/linux/vgaarb.h:99:34: warning: 'struct pci_dev' declared inside parameter list
include/linux/vgaarb.h:109:6: warning: 'struct pci_dev' declared inside parameter list
include/linux/vgaarb.h:121:8: warning: 'struct pci_dev' declared inside parameter list
include/linux/vgaarb.h:140:37: warning: 'struct pci_dev' declared inside parameter list
Signed-off-by: NRandy Dunlap <rdunlap@xenotime.net>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Macros in <linux/pinctrl/machine.h> call ARRAY_SIZE(), the definition of
which eventually calls BUILD_BUG_ON_ZERO(), which is defined in
<linux/bug.h>. Include that so that every .c file using the pinctrl macros
doesn't have to do that itself.
Signed-off-by: NStephen Warren <swarren@wwwdotorg.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The pinctrl_register_mappings is defined in core.c, so change the dependent
macro from CONFIG_MUX to CONFIG_PINCTRL.

The compile error message is:
drivers/pinctrl/core.c:886: error: redefinition of 'pinctrl_register_mappings'
include/linux/pinctrl/machine.h:160: note: previous definition of 'pinctrl_register_mappings' was here
make[2]: *** [drivers/pinctrl/core.o] Error 1
make[1]: *** [drivers/pinctrl] Error 2
make: *** [drivers] Error 2
Acked-by: NStephen Warren <swarren@wwwdotorg.org>
Signed-off-by: NDong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

It makes no sense to export this trivial function.  Make it a static inline
instead.

This patch also drops virq_to_hw from arch/c6x since it is unused by that
architecture.

v2: Move irq_hw_number_t into types.h to fix ARM build failure
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>

musb can be suspended at the time some other driver wants to do ulpi
transfers using usb_phy_io_* functions, and that can cause data abort,
as it happened with isp1704_charger:
http://article.gmane.org/gmane.linux.kernel/1226122

Add pm_runtime to ulpi functions to rectify this. This also adds io_dev
to usb_phy so that pm_runtime_* functions can be used.

Cc: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: NGrazvydas Ignotas <notasas@gmail.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

Also remove two warnings when CONFIG_SND_DEBUG is not set:

sound/pci/hda/patch_hdmi.c: In function ‘hdmi_intrinsic_event’:
sound/pci/hda/patch_hdmi.c:761:6: warning: unused variable ‘eldv’ [-Wunused-variable]
sound/pci/hda/patch_hdmi.c:760:6: warning: unused variable ‘pd’ [-Wunused-variable]
Signed-off-by: NWu Fengguang <fengguang.wu@intel.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

This patch (as1536) fixes a bug in the USB serial core.  Unloading and
reloading a serial driver while a serial device is plugged in causes
errors because of the code in usb_serial_disconnect() that tries to
make sure the port_remove method is called.  With the new order of
driver registration introduced in the 3.4 kernel, this is definitely
not the right thing to do (if indeed it ever was).

The patch removes that whole section code, along with the mechanism
for keeping track of each port's registration state, which is no
longer needed.  The driver core can handle all that stuff for us.

Note: This has been tested only with one or two USB serial drivers.
In theory, other drivers might still run into trouble.  But if they
do, it will be the fault of the drivers, not of this patch -- that is,
the drivers will need to be fixed.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Reported-and-tested-by: NJohan Hovold <jhovold@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

When the control-rate tables are not set up correctly, it makes
little sense to spam the logs, thus change the WARN_ON to WARN_ON_ONCE.
Signed-off-by: NLarry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Workaround dropped notifications in the iir register.  Register reads
coincident with new interrupt notifications sometimes result in this
device clearing the interrupt event without reporting it in the read
data.

The serial core already has a heuristic for determining when a device
has an untrustworthy iir register.  In this case when we apriori know
that the iir is faulty use a flag (UPF_BUG_THRE) to bypass the test and
force usage of the background timer.

[stable: 3.3.x]
Acked-by: NAlan Cox <alan@linux.intel.com>
Cc: stable <stable@vger.kernel.org>
Reported-by: NNhan H Mai <nhan.h.mai@intel.com>
Reported-by: NSudhakar Mamillapalli <sudhakar@fb.com>
Tested-by: NNhan H Mai <nhan.h.mai@intel.com>
Tested-by: NSudhakar Mamillapalli <sudhakar@fb.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This reverts commit 448ac154.

The semantic of UPF_IIR_ONCE is only guaranteed to workaround the race
condition in the kt serial's iir register if the only source of
interrupts is THRE (fifo-empty) events.  An modem status event at the
wrong time can again cause an iir read to drop the 'empty' status
leading to a hang.  So, revert this in preparation for using the
existing "I don't trust my iir register" workaround in the 8250 core
(UART_BUG_THRE).

[stable: 3.3.x]
Cc: stable <stable@vger.kernel.org>
Acked-by: NAlan Cox <alan@linux.intel.com>
Cc: Sudhakar Mamillapalli <sudhakar@fb.com>
Reported-by: NNhan H Mai <nhan.h.mai@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We may hit this in xt_LOG:

net/built-in.o:xt_LOG.c:function dump_ipv6_packet:
	error: undefined reference to 'ip6t_ext_hdr'

happens with these config options:

CONFIG_NETFILTER_XT_TARGET_LOG=y
CONFIG_IP6_NF_IPTABLES=m

ip6t_ext_hdr is fairly small and it is called in the packet path.
Make it static inline.
Reported-by: NSimon Kirby <sim@netnation.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

Commit e52ac339 ('net: Use device
model to get driver name in skb_gso_segment()') removed the only
in-tree caller of ethtool ops that doesn't hold the RTNL lock.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts commit c16e981b2fd9455af670a69a84f4c8cf07e12658, because
it's no longer useful once MSI support is reverted.
Signed-off-by: NChris Ball <cjb@laptop.org>

MSI on my O2Micro OZ600 SD card reader is broken.  This patch adds a quirk
to disable MSI on these controllers.
Signed-off-by: NManuel Lauss <manuel.lauss@googlemail.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

commit 2f533844 (tcp: allow splice() to build full TSO packets) added
a regression for splice() calls using SPLICE_F_MORE.

We need to call tcp_flush() at the end of the last page processed in
tcp_sendpages(), or else transmits can be deferred and future sends
stall.

Add a new internal flag, MSG_SENDPAGE_NOTLAST, acting like MSG_MORE, but
with different semantic.

For all sendpage() providers, its a transparent change. Only
sock_sendpage() and tcp_sendpages() can differentiate the two different
flags provided by pipe_to_sendpage()
Reported-by: NTom Herbert <therbert@google.com>
Cc: Nandita Dukkipati <nanditad@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: H.K. Jerry Chu <hkchu@google.com>
Cc: Maciej Żenczykowski <maze@google.com>
Cc: Mahesh Bandewar <maheshb@google.com>
Cc: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: NEric Dumazet <eric.dumazet@gmail&gt;com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is the fallout from adding memcpy alignment workaround for certain
IOATDMA hardware. NetDMA will only use DMA engine that can handle byte align
ops.
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NDave Jiang <dave.jiang@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Although mem_cgroup_uncharge_swap has an empty placeholder for
!CONFIG_CGROUP_MEM_RES_CTLR_SWAP the definition is placed in the
CONFIG_SWAP ifdef block so we are missing the same definition for
!CONFIG_SWAP which implies !CONFIG_CGROUP_MEM_RES_CTLR_SWAP.

This has not been an issue before, because mem_cgroup_uncharge_swap was
not called from !CONFIG_SWAP context.  But Hugh Dickins has a cleanup
patch to call __mem_cgroup_commit_charge_swapin which is defined also
for !CONFIG_SWAP.

Let's move both the empty definition and declaration outside of the
CONFIG_SWAP block to avoid the following compilation error:

  mm/memcontrol.c: In function '__mem_cgroup_commit_charge_swapin':
  mm/memcontrol.c:2837: error: implicit declaration of function 'mem_cgroup_uncharge_swap'

if CONFIG_SWAP is disabled.
Reported-by: NDavid Rientjes <rientjes@google.com>
Signed-off-by: NMichal Hocko <mhocko@suse.cz>
Cc: Hugh Dickins <hughd@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

debugfs and a few other drivers use an open-coded version of
simple_open() to pass a pointer from the file to the read/write file
ops.  Add support for this simple case to libfs so that we can remove
the many duplicate copies of this simple function.
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

To ensure that old user space versions do not accidentally pick up and
try to use the management channel, use a different channel number.
Reported-by: NKeith Packard <keithp@keithp.com>
Acked-by: NJohan Hedberg <johan.hedberg@intel.com>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NGustavo Padovan <gustavo@padovan.org>

Commit f04565dd (dev: use name hash for dev_seq_ops) added a second
regression, as some devices are missing from /proc/net/dev if many
devices are defined.

When seq_file buffer is filled, the last ->next/show() method is
canceled (pos value is reverted to value prior ->next() call)

Problem is after above commit, we dont restart the lookup at right
position in ->start() method.

Fix this by removing the internal 'pos' pointer added in commit, since
we need to use the 'loff_t *pos' provided by seq_file layer.

This also reverts commit 5cac98dd (net: Fix corruption
in /proc/*/net/dev_mcast), since its not needed anymore.
Reported-by: NBen Greear <greearb@candelatech.com>
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Cc: Mihai Maruseac <mmaruseac@ixiacom.com>
Tested-by: NBen Greear <greearb@candelatech.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It just bloats the audit data structure for no good reason, since the
only time those fields are filled are just before calling the
common_lsm_audit() function, which is also the only user of those
fields.

So just make them be the arguments to common_lsm_audit(), rather than
bloating that structure that is passed around everywhere, and is
initialized in hot paths.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

After shrinking the common_audit_data stack usage for private LSM data I'm
not going to shrink the data union.  To do this I'm going to move anything
larger than 2 void * ptrs to it's own structure and require it to be declared
separately on the calling stack.  Thus hot paths which don't need more than
a couple pointer don't have to declare space to hold large unneeded
structures.  I could get this down to one void * by dealing with the key
struct and the struct path.  We'll see if that is helpful after taking care of
networking.
Signed-off-by: NEric Paris <eparis@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Linus found that the gigantic size of the common audit data caused a big
perf hit on something as simple as running stat() in a loop.  This patch
requires LSMs to declare the LSM specific portion separately rather than
doing it in a union.  Thus each LSM can be responsible for shrinking their
portion and don't have to pay a penalty just because other LSMs have a
bigger space requirement.
Signed-off-by: NEric Paris <eparis@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

1M section, 64k page count also should be rounded up so this patch
rounds up them and caculates page count of them properly and also
checks memory flags from user.
Signed-off-by: NInki Dae <inki.dae@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>

Builds of the openrisc or1ksim_defconfig show the following:

  In file included from arch/openrisc/include/generated/asm/cmpxchg.h:1:0,
                   from include/asm-generic/atomic.h:18,
                   from arch/openrisc/include/generated/asm/atomic.h:1,
                   from include/linux/atomic.h:4,
                   from include/linux/dcache.h:4,
                   from fs/notify/fsnotify.c:19:
  include/asm-generic/cmpxchg.h: In function '__xchg':
  include/asm-generic/cmpxchg.h:34:20: error: expected ')' before 'u8'
  include/asm-generic/cmpxchg.h:34:20: warning: type defaults to 'int' in type name

and many more lines of similar errors.  It seems specific to the or32
because most other platforms have an arch specific component that would
have already included types.h ahead of time, but the o32 does not.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jonas Bonn <jonas@southpole.se>
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: David Howells <dhowells@redhat.com
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 313162d0 ("device.h: audit and cleanup users in main include
dir") exchanged an include <linux/device.h> for a struct *device but in
actuality I misread this file when creating 313162d0 and it should have
remained an include.

There were no build regressions since all consumers were already getting
device.h anyway, but make it right regardless.
Reported-by: NStefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit bf4289cb ("ATMEL: fix nand ecc support") indicated that it
wanted to "Move platform data to a common header
include/linux/platform_data/atmel_nand.h" and the new header even had
re-include protectors with:

    #ifndef __ATMEL_NAND_H__

However, the file that was added was simply called atmel.h
and this caused avr32 defconfig to fail with:

  In file included from arch/avr32/boards/atstk1000/setup.c:22:
  arch/avr32/mach-at32ap/include/mach/board.h:10:44: error: linux/platform_data/atmel_nand.h: No such file or directory
  In file included from arch/avr32/boards/atstk1000/setup.c:22:
  arch/avr32/mach-at32ap/include/mach/board.h:121: warning: 'struct atmel_nand_data' declared inside parameter list
  arch/avr32/mach-at32ap/include/mach/board.h:121: warning: its scope is only this definition or declaration, which is probably not what you want
  make[2]: *** [arch/avr32/boards/atstk1000/setup.o] Error 1

It seems the scope of the file contents will expand beyond
just nand, so ignore the original intention, and fix up the
users who reference the bad name with the _nand suffix.

CC: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
CC: David Woodhouse <dwmw2@infradead.org>
Acked-by: NHans-Christian Egtvedt <egtvedt@samfundet.no>
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Totally unexpected that this regressed. Luckily it sounds like we just
need to have dmar disable on the igfx, not the entire system. At least
that's what a few days of testing between Tony Vroon and me indicates.
Reported-by: NTony Vroon <tony@linx.net>
Cc: Tony Vroon <tony@linx.net>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=43024Acked-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We can deadlock if we have a write oplock and two processes
use the same file handle. In this case the first process can't
unlock its lock if the second process blocked on the lock in the
same time.

Fix it by using posix_lock_file rather than posix_lock_file_wait
under cinode->lock_mutex. If we request a blocking lock and
posix_lock_file indicates that there is another lock that prevents
us, wait untill that lock is released and restart our call.

Cc: stable@kernel.org
Acked-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NPavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>