The script “checkpatch.pl” pointed information out like the following.

Comparison to NULL could be written ...

Thus fix the affected source code places.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Reviewed-by: Yan, Zheng <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

The script "checkpatch.pl" pointed information out like the following.

WARNING: void function return statements are not generally useful

Thus remove such a statement in the affected function.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Reviewed-by: Yan, Zheng <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Omit an extra message for a memory allocation failure in this function.

This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Reviewed-by: Yan, Zheng <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

When a user requests SEEK_HOLE or SEEK_DATA with a negative offset
ceph_llseek should return -ENXIO.  Currently -EINVAL is being returned for
SEEK_DATA and 0 for SEEK_HOLE.
Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Improve accuracy of statfs reporting for Ceph filesystems comprising
exactly one data pool. In this case, the Ceph monitor can now report
the space usage for the single data pool instead of the global data
for the entire Ceph cluster. Include support for this message in
mon_client and leverage it in ceph/super.
Signed-off-by: Douglas Fuller <dfuller@redhat.com>
Reviewed-by: Yan, Zheng <zyan@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Inode can be moved between snap realms. It's possible inode is moved
into a snap realm whose seq number is smaller than old snap realm's.
So there is no guarantee that seq number inode's snap context always
increases.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Before sending new flushsnap message, check if there are old
flushsnap messages that need to be re-sent. If there are, re-send
old messages first. This guarantees ordering of flushsnap messages.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Need to drop cap reference before retry. Besides, it's better to
redo file write checks for each retry because we re-lock inode.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Snapdir inode has no capability. __choose_mds() should choose mds
base on capabilities of snapdir's parent inode.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

In LSSNAP case, req->r_dentry is already set to snapdir dentry.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Ensure that when writeback errors are marked that we report those to all
file descriptions that were open at the time of the error.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

These flags tell mds if there is pending capsnap explicitly.
Without this explicit notification, mds can only conclude if
client has pending capsnap. The method mds use is inefficient
and error-prone.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

startsync is a no-op, has been for years.  Remove it.

Link: http://tracker.ceph.com/issues/20604Signed-off-by: Yanhu Cao <gmayyyha@gmail.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

  drivers/block/rbd.c: In function 'rbd_acquire_lock':
  drivers/block/rbd.c:3602:44: error: 'ret' may be used uninitialized in this function [-Werror=maybe-uninitialized]

Silence the warning, found it when built old kernel(3.10) with
OBS(opensuse build service).
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

OSD has a configurable limitation of max write size. OSD return
error if write request size is larger than the limitation. For now,
set max write size to CEPH_MSG_MAX_DATA_LEN. It should be small
enough.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

libceph returns -EIO when read size > CEPH_MSG_MAX_DATA_LEN.

Link: http://tracker.ceph.com/issues/20528Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Pull MIPS fixes from Ralf Baechle:
 "The two indirect syscall fixes have sat in linux-next for a few days.
  I did check back with a hardware designer to ensure a SYNC is really
  what's required for the GIC fix and so the GIC fix didn't make it into
  to linux-next in time for this final pull request.

  It builds in local build tests and passes Imagination's test system"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  irqchip: mips-gic: SYNC after enabling GIC region
  MIPS: Remove pt_regs adjustments in indirect syscall handler
  MIPS: seccomp: Fix indirect syscall args

Pull x86 fixes from Thomas Gleixner:

 - Expand the space for uncompressing as the LZ4 worst case does not fit
   into the currently reserved space

 - Validate boot parameters more strictly to prevent out of bound access
   in the decompressor/boot code

 - Fix off by one errors in get_segment_base()

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot: Prevent faulty bootparams.screeninfo from causing harm
  x86/boot: Provide more slack space during decompression
  x86/ldt: Fix off by one in get_segment_base()

Pull timer fix from Thomas Gleixner:
 "A single fix for a thinko in the raw timekeeper update which causes
  clock MONOTONIC_RAW to run with erratically increased frequency"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  time: Fix ktime_get_raw() incorrect base accumulation

Pull perf fixes from Thomas Gleixner:

 - Prevent a potential inconistency in the perf user space access which
   might lead to evading sanity checks.

 - Prevent perf recording function trace entries twice

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/ftrace: Fix double traces of perf on ftrace:function
  perf/core: Fix potential double-fetch bug

Pull cifs version warning fix from Steve French:
 "As requested, additional kernel warning messages to clarify the
  default dialect changes"

[ There is still some discussion about exactly which version should be
  the new default.  Longer-term we have auto-negotiation coming, but
  that's not there yet..  - Linus ]

* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
  Fix warning messages when mounting to older servers

Pull ARM SoC fixes from Olof Johansson:
 "A couple of late-arriving fixes before final 4.13:

   - A few reverts of DT bindings on Allwinner for their ethernet
     driver. Discussion didn't converge, and since bindings are
     considered ABI it makes sense to revert instead of having to
     support two bindings long-term.

   - A fix to enumerate GPIOs properly on Marvell Armada AP806"

* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  arm64: dts: marvell: fix number of GPIOs in Armada AP806 description
  arm: dts: sunxi: Revert EMAC changes
  arm64: dts: allwinner: Revert EMAC changes
  dt-bindings: net: Revert sun8i dwmac binding

mvebu fixes for 4.13 (part 3)

Fix number of GPIOs in AP806 description for Armada 7K/8K

* tag 'mvebu-fixes-4.13-3' of git://git.infradead.org/linux-mvebu:
  arm64: dts: marvell: fix number of GPIOs in Armada AP806 description
Signed-off-by: Olof Johansson <olof@lixom.net>

Pull i2c fixes from Wolfram Sang:
 "The ismt driver had a problem with a rarely used transaction type and
  the designware driver was made even more robust against non standard
  ACPI tables"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: designware: Round down ACPI provided clk to nearest supported clk
  i2c: ismt: Return EMSGSIZE for block reads with bogus length
  i2c: ismt: Don't duplicate the receive length for block reads

The race was introduced by me in commit 971316f0 ("epoll:
ep_unregister_pollwait() can use the freed pwq->whead").  I did not
realize that nothing can protect eventpoll after ep_poll_callback() sets
->whead = NULL, only whead->lock can save us from the race with
ep_free() or ep_remove().

Move ->whead = NULL to the end of ep_poll_callback() and add the
necessary barriers.

TODO: cleanup the ewake/EPOLLEXCLUSIVE logic, it was confusing even
before this patch.

Hopefully this explains use-after-free reported by syzcaller:

	BUG: KASAN: use-after-free in debug_spin_lock_before
	...
	 _raw_spin_lock_irqsave+0x4a/0x60 kernel/locking/spinlock.c:159
	 ep_poll_callback+0x29f/0xff0 fs/eventpoll.c:1148

this is spin_lock(eventpoll->lock),

	...
	Freed by task 17774:
	...
	 kfree+0xe8/0x2c0 mm/slub.c:3883
	 ep_free+0x22c/0x2a0 fs/eventpoll.c:865

Fixes: 971316f0 ("epoll: ep_unregister_pollwait() can use the freed pwq->whead")
Reported-by: 范龙飞 <long7573@126.com>
Cc: stable@vger.kernel.org
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull networking fixes from David Miller:

 1) Fix handling of pinned BPF map nodes in hash of maps, from Daniel
    Borkmann.

 2) IPSEC ESP error paths leak memory, from Steffen Klassert.

 3) We need an RCU grace period before freeing fib6_node objects, from
    Wei Wang.

 4) Must check skb_put_padto() return value in HSR driver, from FLorian
    Fainelli.

 5) Fix oops on PHY probe failure in ftgmac100 driver, from Andrew
    Jeffery.

 6) Fix infinite loop in UDP queue when using SO_PEEK_OFF, from Eric
    Dumazet.

 7) Use after free when tcf_chain_destroy() called multiple times, from
    Jiri Pirko.

 8) Fix KSZ DSA tag layer multiple free of SKBS, from Florian Fainelli.

 9) Fix leak of uninitialized memory in sctp_get_sctp_info(),
    inet_diag_msg_sctpladdrs_fill() and inet_diag_msg_sctpaddrs_fill().
    From Stefano Brivio.

10) L2TP tunnel refcount fixes from Guillaume Nault.

11) Don't leak UDP secpath in udp_set_dev_scratch(), from Yossi
    Kauperman.

12) Revert a PHY layer change wrt. handling of PHY_HALTED state in
    phy_stop_machine(), it causes regressions for multiple people. From
    Florian Fainelli.

13) When packets are sent out of br0 we have to clear the
    offload_fwdq_mark value.

14) Several NULL pointer deref fixes in packet schedulers when their
    ->init() routine fails. From Nikolay Aleksandrov.

15) Aquantium devices cannot checksum offload correctly when the packet
    is <= 60 bytes. From Pavel Belous.

16) Fix vnet header access past end of buffer in AF_PACKET, from
    Benjamin Poirier.

17) Double free in probe error paths of nfp driver, from Dan Carpenter.

18) QOS capability not checked properly in DCB init paths of mlx5
    driver, from Huy Nguyen.

19) Fix conflicts between firmware load failure and health_care timer in
    mlx5, also from Huy Nguyen.

20) Fix dangling page pointer when DMA mapping errors occur in mlx5,
    from Eran Ben ELisha.

21) ->ndo_setup_tc() in bnxt_en driver doesn't count rings properly,
    from Michael Chan.

22) Missing MSIX vector free in bnxt_en, also from Michael Chan.

23) Refcount leak in xfrm layer when using sk_policy, from Lorenzo
    Colitti.

24) Fix copy of uninitialized data in qlge driver, from Arnd Bergmann.

25) bpf_setsockopts() erroneously always returns -EINVAL even on
    success. Fix from Yuchung Cheng.

26) tipc_rcv() needs to linearize the SKB before parsing the inner
    headers, from Parthasarathy Bhuvaragan.

27) Fix deadlock between link status updates and link removal in netvsc
    driver, from Stephen Hemminger.

28) Missed locking of page fragment handling in ESP output, from Steffen
    Klassert.

29) Fix refcnt leak in ebpf congestion control code, from Sabrina
    Dubroca.

30) sxgbe_probe_config_dt() doesn't check devm_kzalloc()'s return value,
    from Christophe Jaillet.

31) Fix missing ipv6 rx_dst_cookie update when rx_dst is updated during
    early demux, from Paolo Abeni.

32) Several info leaks in xfrm_user layer, from Mathias Krause.

33) Fix out of bounds read in cxgb4 driver, from Stefano Brivio.

34) Properly propagate obsolete state of route upwards in ipv6 so that
    upper holders like xfrm can see it. From Xin Long.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (118 commits)
  udp: fix secpath leak
  bridge: switchdev: Clear forward mark when transmitting packet
  mlxsw: spectrum: Forbid linking to devices that have uppers
  wl1251: add a missing spin_lock_init()
  Revert "net: phy: Correctly process PHY_HALTED in phy_stop_machine()"
  net: dsa: bcm_sf2: Fix number of CFP entries for BCM7278
  kcm: do not attach PF_KCM sockets to avoid deadlock
  sch_tbf: fix two null pointer dereferences on init failure
  sch_sfq: fix null pointer dereference on init failure
  sch_netem: avoid null pointer deref on init failure
  sch_fq_codel: avoid double free on init failure
  sch_cbq: fix null pointer dereferences on init failure
  sch_hfsc: fix null pointer deref and double free on init failure
  sch_hhf: fix null pointer dereference on init failure
  sch_multiq: fix double free on init failure
  sch_htb: fix crash on init failure
  net/mlx5e: Fix CQ moderation mode not set properly
  net/mlx5e: Fix inline header size for small packets
  net/mlx5: E-Switch, Unload the representors in the correct order
  net/mlx5e: Properly resolve TC offloaded ipv6 vxlan tunnel source address
  ...

Pull ceph fix from Ilya Dryomov:
 "ceph fscache page locking fix from Zheng, marked for stable"

* tag 'ceph-for-4.13-rc8' of git://github.com/ceph/ceph-client:
  ceph: fix readpage from fscache

Pull input fixes from Dmitry Torokhov:
 "Just a couple drivers fixes (Synaptics PS/2, Xpad)"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: xpad - fix PowerA init quirk for some gamepad models
  Input: synaptics - fix device info appearing different on reconnect

Pull two more MMC fixes from Ulf Hansson:
 "MMC core:
   - Fix block status codes

  MMC host:
   - sdhci-xenon: Fix SD bus voltage select"

* tag 'mmc-v4.13-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
  mmc: sdhci-xenon: add set_power callback
  mmc: block: Fix block status codes

Pull sound fixes from Takashi Iwai:
 "Three regression fixes that should be addressed before the final
  release: a missing mutex call in OSS PCM emulation ioctl, ASoC rt5670
  headset detection breakage, and a regression in simple-card parser
  code"

* tag 'sound-4.13-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ASoC: simple_card_utils: fix fallback when "label" property isn't present
  ALSA: pcm: Fix power lock unbalance via OSS emulation
  ASoC: rt5670: Fix GPIO headset detection regression

Pull s390 fixes from Martin Schwidefsky:
 "Three more bug fixes for v4.13.

  The two memory management related fixes are quite new, they fix kernel
  crashes that can be triggered by user space.

  The third commit fixes a bug in the vfio ccw translation code"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/mm: fix BUG_ON in crst_table_upgrade
  s390/mm: fork vs. 5 level page tabel
  vfio: ccw: fix bad ptr math for TIC cda translation

Pull crypto fixes from Herbert Xu:
 "This fixes the following issues:

   - Regression in chacha20 handling of chunked input

   - Crash in algif_skcipher when used with async io

   - Potential bogus pointer dereference in lib/mpi"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: algif_skcipher - only call put_page on referenced and used pages
  crypto: testmgr - add chunked test cases for chacha20
  crypto: chacha20 - fix handling of chunked input
  lib/mpi: kunmap after finishing accessing buffer

After commit dce4551c ("udp: preserve head state for IP_CMSG_PASSSEC")
we preserve the secpath for the whole skb lifecycle, but we also
end up leaking a reference to it.

We must clear the head state on skb reception, if secpath is
present.

Fixes: dce4551c ("udp: preserve head state for IP_CMSG_PASSSEC")
Signed-off-by: Yossi Kuperman <yossiku@mellanox.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Commit 6bc506b4 ("bridge: switchdev: Add forward mark support for
stacked devices") added the 'offload_fwd_mark' bit to the skb in order
to allow drivers to indicate to the bridge driver that they already
forwarded the packet in L2.

In case the bit is set, before transmitting the packet from each port,
the port's mark is compared with the mark stored in the skb's control
block. If both marks are equal, we know the packet arrived from a switch
device that already forwarded the packet and it's not re-transmitted.

However, if the packet is transmitted from the bridge device itself
(e.g., br0), we should clear the 'offload_fwd_mark' bit as the mark
stored in the skb's control block isn't valid.

This scenario can happen in rare cases where a packet was trapped during
L3 forwarding and forwarded by the kernel to a bridge device.

Fixes: 6bc506b4 ("bridge: switchdev: Add forward mark support for stacked devices")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reported-by: Yotam Gigi <yotamg@mellanox.com>
Tested-by: Yotam Gigi <yotamg@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>