* new field - pipe->files; number of struct file over that pipe (all
  sharing the same inode, of course); protected by inode->i_lock.
* pipe_release() decrements pipe->files, clears inode->i_pipe when
  if the counter has reached 0 (all under ->i_lock) and, in that case,
  frees pipe after having done pipe_unlock()
* fifo_open() starts with grabbing ->i_lock, and either bumps pipe->files
  if ->i_pipe was non-NULL or allocates a new pipe (dropping and regaining
  ->i_lock) and rechecks ->i_pipe; if it's still NULL, inserts new pipe
  there, otherwise bumps ->i_pipe->files and frees the one we'd allocated.
  At that point we know that ->i_pipe is non-NULL and won't go away, so
  we can do pipe_lock() on it and proceed as we used to.  If we end up
  failing, decrement pipe->files and if it reaches 0 clear ->i_pipe and
  free the sucker after pipe_unlock().
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

* use the fact that file_inode(file)->i_pipe doesn't change
  while the file is opened - no locks needed to access that.
* switch to pipe_lock/pipe_unlock where it's easy to do
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

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

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

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

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

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

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

... and take to fs/read_write.c
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

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

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

... so that writev(2) doesn't miss it.  Get rid of hpfs_file_write().
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

look for file_capable() in there...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

... and provide namespace_lock() as a trivial wrapper;
switch to those two consistently.

Result is patterned after rtnl_lock/rtnl_unlock pair.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

which allows to kill the last argument of umount_tree() and make release_mounts()
static.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

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

... it's always &unmounted.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

global list of release_mounts() fodder, protected by namespace_sem;
eventually, all umount_tree() callers will use it as kill list.
Helper picking the contents of that list, releasing namespace_sem
and doing release_mounts() on what it got.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

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

do_loopback calls lock_mount(path) and forget to unlock_mount
if clone_mnt or copy_mnt fails.

[   77.661566] ================================================
[   77.662939] [ BUG: lock held when returning to user space! ]
[   77.664104] 3.9.0-rc5+ #17 Not tainted
[   77.664982] ------------------------------------------------
[   77.666488] mount/514 is leaving the kernel with locks still held!
[   77.668027] 2 locks held by mount/514:
[   77.668817]  #0:  (&sb->s_type->i_mutex_key#7){+.+.+.}, at: [<ffffffff811cca22>] lock_mount+0x32/0xe0
[   77.671755]  #1:  (&namespace_sem){+++++.}, at: [<ffffffff811cca3a>] lock_mount+0x4a/0xe0
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

	* check for proc_mkdir() failures
	* fix buffer overrun - sizeof(format string) is *not* enough to
hold sprintf() result.
	* use proc_remove_subtree(); life's much easier with it
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

just what it sounds like; do that only to procfs subtrees you've
created - doing that to something shared with another driver is
not only antisocial, but might cause interesting races with
proc_create() and its ilk.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

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

Pull vfs fixes from Al Viro:
 "stable fodder; assorted deadlock fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  vt: synchronize_rcu() under spinlock is not nice...
  Nest rename_lock inside vfsmount_lock
  Don't bother with redoing rw_verify_area() from default_file_splice_from()

vcs_poll_data_free() calls unregister_vt_notifier(), which calls
atomic_notifier_chain_unregister(), which calls synchronize_rcu().
Do it *after* we'd dropped ->f_lock.

Cc: stable@vger.kernel.org (all kernels since 2.6.37)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

... lest we get livelocks between path_is_under() and d_path() and friends.

The thing is, wrt fairness lglocks are more similar to rwsems than to rwlocks;
it is possible to have thread B spin on attempt to take lock shared while thread
A is already holding it shared, if B is on lower-numbered CPU than A and there's
a thread C spinning on attempt to take the same lock exclusive.

As the result, we need consistent ordering between vfsmount_lock (lglock) and
rename_lock (seq_lock), even though everything that takes both is going to take
vfsmount_lock only shared.
Spotted-by: Brad Spengler <spender@grsecurity.net>
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Pull networking fixes from David Miller:

 1) Always increment IPV4 ID field in encapsulated GSO packets, even
    when DF is set.  Regression fix from Pravin B Shelar.

 2) Fix per-net subsystem initialization in netfilter conntrack,
    otherwise we may access dynamically allocated memory before it is
    actually allocated.  From Gao Feng.

 3) Fix DMA buffer lengths in iwl3945 driver, from Stanislaw Gruszka.

 4) Fix race between submission of sync vs async commands in mwifiex
    driver, from Amitkumar Karwar.

 5) Add missing cancel of command timer in mwifiex driver, from Bing
    Zhao.

 6) Missing SKB free in rtlwifi USB driver, from Jussi Kivilinna.

 7) Thermal layer tries to use a genetlink multicast string that is
    longer than the 16 character limit.  Fix it and add a BUG check to
    prevent this kind of thing from happening in the future.

 From Masatake YAMATO.

 8) Fix many bugs in the handling of the teardown of L2TP connections,
    UDP encapsulation instances, and sockets.  From Tom Parkin.

 9) Missing socket release in IRDA, from Kees Cook.

10) Fix fec driver modular build, from Fabio Estevam.

11) Erroneous use of kfree() instead of free_netdev() in lantiq_etop,
    from Wei Yongjun.

12) Fix bugs in handling of queue numbers and steering rules in mlx4
    driver, from Moshe Lazer, Hadar Hen Zion, and Or Gerlitz.

13) Some FOO_DIAG_MAX constants were defined off by one, fix from Andrey
    Vagin.

14) TCP segmentation deferral is unintentionally done too strongly,
    breaking ACK clocking.  Fix from Eric Dumazet.

15) net_enable_timestamp() can legitimately be invoked from software
    interrupts, and in a way that is safe, so remove the WARN_ON().
    Also from Eric Dumazet.

16) Fix use after free in VLANs, from Cong Wang.

17) Fix TCP slow start retransmit storms after SACK reneging, from
    Yuchung Cheng.

18) Unix socket release should mark a socket dead before NULL'ing out
    sock->sk, otherwise we can race.  Fix from Paul Moore.

19) IPV6 addrconf code can try to free static memory, from Hong Zhiguo.

20) Fix register mis-programming, NULL pointer derefs, and wrong PHC
    clock frequency in IGB driver.  From Lior LevyAlex Williamson, Jiri
    Benc, and Jeff Kirsher.

21) skb->ip_summed logic in pch_gbe driver is reversed, breaking packet
    forwarding.  Fix from Veaceslav Falico.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (65 commits)
  ipv4: Fix ip-header identification for gso packets.
  bonding: remove already created master sysfs link on failure
  af_unix: dont send SCM_CREDENTIAL when dest socket is NULL
  pch_gbe: fix ip_summed checksum reporting on rx
  igb: fix PHC stopping on max freq
  igb: make sensor info static
  igb: SR-IOV init reordering
  igb: Fix null pointer dereference
  igb: fix i350 anti spoofing config
  ixgbevf: don't release the soft entries
  ipv6: fix bad free of addrconf_init_net
  unix: fix a race condition in unix_release()
  tcp: undo spurious timeout after SACK reneging
  bnx2x: fix assignment of signed expression to unsigned variable
  bridge: fix crash when set mac address of br interface
  8021q: fix a potential use-after-free
  net: remove a WARN_ON() in net_enable_timestamp()
  tcp: preserve ACK clocking in TSO
  net: fix *_DIAG_MAX constants
  net/mlx4_core: Disallow releasing VF QPs which have steering rules
  ...

Pull NFS client bugfixes from Trond Myklebust:
 - Fix an NFSv4 idmapper regression
 - Fix an Oops in the pNFS blocks client
 - Fix up various issues with pNFS layoutcommit
 - Ensure correct read ordering of variables in
   rpc_wake_up_task_queue_locked

* tag 'nfs-for-3.9-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  SUNRPC: Add barriers to ensure read ordering in rpc_wake_up_task_queue_locked
  NFSv4.1: Add a helper pnfs_commit_and_return_layout
  NFSv4.1: Always clear the NFS_INO_LAYOUTCOMMIT in layoutreturn
  NFSv4.1: Fix a race in pNFS layoutcommit
  pnfs-block: removing DM device maybe cause oops when call dev_remove
  NFSv4: Fix the string length returned by the idmapper

ip-header id needs to be incremented even if IP_DF flag is set.
This behaviour was changed in commit 490ab081
(IP_GRE: Fix IP-Identification).

Following patch fixes it so that identification is always
incremented.
Reported-by: Cong Wang <amwang@redhat.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

If slave sysfs symlink failes to be created - we end up without removing
the master sysfs symlink. Remove it in case of failure.
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

SCM_SCREDENTIALS should apply to write() syscalls only either source or destination
socket asserted SOCK_PASSCRED. The original implememtation in maybe_add_creds is wrong,
and breaks several LSB testcases ( i.e. /tset/LSB.os/netowkr/recvfrom/T.recvfrom).
Origionally-authored-by: Karel Srot <ksrot@redhat.com>
Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Jeff Kirsher says:

====================
This series contains updates to ixgbevf and igb.

The ixgbevf calls to pci_disable_msix() and to free the msix_entries
memory should not occur if device open fails.  Instead they should be
called during device driver removal to balance with the call to
pci_enable_msix() and the call to allocate msix_entries memory
during the device probe and driver load.

The remaining 4 of 5 igb patches are simple 1-3 line patches to fix
several issues such as possible null pointer dereference, PHC stopping
on max frequency, make sensor info static and SR-IOV initialization
reordering.

The remaining igb patch to fix anti-spoofing config fixes a problem
in i350 where anti spoofing configuration was written into a wrong
register.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

skb->ip_summed should be CHECKSUM_UNNECESSARY when the driver reports that
checksums were correct and CHECKSUM_NONE in any other case. They're
currently placed vice versa, which breaks the forwarding scenario. Fix it
by placing them as described above.
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

For 82576 MAC type, max_adj is reported as 1000000000 ppb. However, if
this value is passed to igb_ptp_adjfreq_82576, incvalue overflows out of
INCVALUE_82576_MASK, resulting in setting of zero TIMINCA.incvalue, stopping
the PHC (instead of going at twice the nominal speed).

Fix the advertised max_adj value to the largest value hardware can handle.
As there is no min_adj value available (-max_adj is used instead), this will
also prevent stopping the clock intentionally. It's probably not a big deal,
other igb MAC types don't support stopping the clock, either.
Signed-off-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Matthew Vick <matthew.vick@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

Trivial sparse warning.
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

igb is ineffective at setting a lower total VFs because:

int pci_sriov_set_totalvfs(struct pci_dev *dev, u16 numvfs)
{
        ...
        /* Shouldn't change if VFs already enabled */
        if (dev->sriov->ctrl & PCI_SRIOV_CTRL_VFE)
                return -EBUSY;

Swap init ordering.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Acked-by: Greg Rose <gregory.v.rose@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

The max_vfs= option has always been self limiting to the number of VFs
supported by the device.  fa44f2f1 added SR-IOV configuration via
sysfs, but in the process broke this self correction factor.  The
failing path is:

igb_probe
  igb_sw_init
    if (max_vfs > 7) {
        adapter->vfs_allocated_count = 7;
    ...
    igb_probe_vfs
    igb_enable_sriov(, max_vfs)
      if (num_vfs > 7) {
        err = -EPERM;
        ...

This leaves vfs_allocated_count = 7 and vf_data = NULL, so we bomb out
when igb_probe finally calls igb_reset.  It seems like a really bad
idea, and somewhat pointless, to set vfs_allocated_count separate from
vf_data, but limiting max_vfs is enough to avoid the null pointer.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Acked-by: Greg Rose <gregory.v.rose@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

Fix a problem in i350 where anti spoofing configuration was written into a
wrong register.
Signed-off-by: Lior Levy <lior.levy@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

When the ixgbevf driver is opened the request to allocate MSIX irq
vectors may fail.  In that case the driver will call ixgbevf_down()
which will call ixgbevf_irq_disable() to clear the HW interrupt
registers and calls synchronize_irq() using the msix_entries pointer in
the adapter structure.  However, when the function to request the MSIX
irq vectors failed it had already freed the msix_entries which causes
an OOPs from using the NULL pointer in synchronize_irq().

The calls to pci_disable_msix() and to free the msix_entries memory
should not occur if device open fails.  Instead they should be called
during device driver removal to balance with the call to
pci_enable_msix() and the call to allocate msix_entries memory
during the device probe and driver load.
Signed-off-by: Li Xun <xunleer.li@huawei.com>
Signed-off-by: Greg Rose <gregory.v.rose@intel.com>
Tested-by: Sibai Li <sibai.li@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

Pull timer fix from Thomas Gleixner:
 "A single bugfix which prevents that a non functional timer device is
  selected to provide the fallback device, which is supposed to serve
  timer interrupts on behalf of non functional devices ..."

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clockevents: Don't allow dummy broadcast timers