When we receives traceless reply for request that created new inode,
we re-send a lookup request to MDS get information of the newly created
inode. (VFS expects FS' callback return an inode in create case)
This breaks one request into two requests. Other client may modify or
move to the new inode in the middle.

When the race happens, ceph_handle_notrace_create() unconditionally
links the dentry for 'create' operation to the inode returned by lookup.
This may confuse VFS when the inode is a directory (VFS does not allow
multiple linkages for directory inode).

This patch makes ceph_handle_notrace_create() when it detect a race.
This event should be rare and it happens only when we talk to old MDS.
Recent MDS does not send traceless reply for request that creates new
inode.
Signed-off-by: Yan, Zheng <zyan@redhat.com>

Signed-off-by: Yan, Zheng <zyan@redhat.com>

So that MDS can check if any request is already completed and process
completed requests in clientreplay stage. When completed requests are
processed in clientreplay stage, MDS can avoid sending traceless
replies.
Signed-off-by: Yan, Zheng <zyan@redhat.com>

Signed-off-by: Ilya Dryomov <idryomov@redhat.com>

TCP_NODELAY socket option set on connection sockets,
disables Nagle’s algorithm and improves latency characteristics.
tcp_nodelay(default)/notcp_nodelay option flags provided to
enable/disable setting the socket option.
Signed-off-by: Chaitanya Huilgol <chaitanya.huilgol@sandisk.com>
[idryomov@redhat.com: NO_TCP_NODELAY -> TCP_NODELAY, minor adjustments]
Signed-off-by: Ilya Dryomov <idryomov@redhat.com>

If the clone is resized down to 0, it becomes standalone.  If such
resize is carried over while an image is mapped we would detect this
and call rbd_dev_parent_put() which means "let go of all parent state,
including the spec(s) of parent images(s)".  This leads to a mismatch
between "rbd info" and sysfs parent fields, so a fix is in order.

    # rbd create --image-format 2 --size 1 foo
    # rbd snap create foo@snap
    # rbd snap protect foo@snap
    # rbd clone foo@snap bar
    # DEV=$(rbd map bar)
    # rbd resize --allow-shrink --size 0 bar
    # rbd resize --size 1 bar
    # rbd info bar | grep parent
            parent: rbd/foo@snap

Before:

    # cat /sys/bus/rbd/devices/0/parent
    (no parent image)

After:

    # cat /sys/bus/rbd/devices/0/parent
    pool_id 0
    pool_name rbd
    image_id 10056b8b4567
    image_name foo
    snap_id 2
    snap_name snap
    overlap 0
Signed-off-by: Ilya Dryomov <idryomov@redhat.com>
Reviewed-by: Josh Durgin <jdurgin@redhat.com>
Reviewed-by: Alex Elder <elder@linaro.org>

ceph_handle_snapdir() checks ceph_mdsc_do_request()'s return value
and creates snapdir inode if it's -ENOENT
Signed-off-by: Yan, Zheng <zyan@redhat.com>

ceph_add_cap() calls __check_cap_issue(), which clears directory
inode' complete flag. so we should set the complete flag for empty
directory should be set after calling ceph_add_cap().
Signed-off-by: Yan, Zheng <zyan@redhat.com>

Signed-off-by: Yan, Zheng <zyan@redhat.com>

remove all unsupported operations from {inode,file}_operations.
Signed-off-by: Yan, Zheng <zyan@redhat.com>

struct timespec uses 'long' to present second and nanosecond. 'long'
is 64 bits on 64bits machine. ceph MDS expects time stamp to be
encoded as struct ceph_timespec, which uses 'u32' to present second
and nanosecond.
Signed-off-by: Yan, Zheng <zyan@redhat.com>

when inode has inline data but its size > PAGE_SIZE (it was truncated
to larger size), previous direct read code return -EIO. This patch adds
code to return zeros for data whose offset > PAGE_SIZE.
Signed-off-by: Yan, Zheng <zyan@redhat.com>

use an atomic variable to track number of sessions, this can avoid block
operation inside wait loops.
Signed-off-by: Yan, Zheng <zyan@redhat.com>

we should not do block operation in wait_event_interruptible()'s condition
check function, but reading inline data can block. so move the read inline
data code to ceph_get_caps()
Signed-off-by: Yan, Zheng <zyan@redhat.com>

check_cap_flush() calls mutex_lock(), which may block. So we can't
use it as condition check function for wait_event();
Signed-off-by: Yan, Zheng <zyan@redhat.com>

header_rwsem should be released on errors.  Also remove useless
rbd_dev->mapping.size != rbd_dev->header.image_size test.
Signed-off-by: Ilya Dryomov <idryomov@redhat.com>

When snaprealm is created, its initial reference count is zero.
But in some rare cases, the newly created snaprealm is not referenced
by anyone. This causes snaprealm with zero reference count not freed.

The fix is set reference count of newly snaprealm to 1. The reference
is return the function who requests to create the snaprealm. When the
function finishes its job, it releases the reference.
Signed-off-by: Yan, Zheng <zyan@redhat.com>

A bug is found in striped_read() of fs/ceph/file.c. striped_read() calls
ceph_zero_pape_vector_range().  The first argument, page_align + read + ret,
passed to ceph_zero_pape_vector_range() is wrong.

When a file has holes, this wrong parameter may cause memory corruption
either in kernal space or user space. Kernel space memory may be corrupted in
the case of non direct IO; user space memory may be corrupted in the case of
direct IO. In the latter case, the application doing direct IO may crash due
to memory corruption, as we have experienced.

The correct value should be initial_align + read + ret, where intial_align =
o_direct ? buf_align : io_align.  Compared with page_align, the current page
offest, initial_align is the initial page offest, which should be used to
calculate the page and offset in ceph_zero_pape_vector_range().
Reported-by: caifeng zhu <zhucaifeng@unissoft-nj.com>
Signed-off-by: Yan, Zheng <zyan@redhat.com>

Remove the function ceph_get_cached_acl() that is not used anywhere.

This was partially found by using a static code analysis program called cppcheck.
Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Reviewed-by: Yan, Zheng <zyan@redhat.com>

It's been largely superseded by dup_token() and unused for over
2 years, identified by cppcheck.
Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
[idryomov@redhat.com: changelog]
Signed-off-by: Ilya Dryomov <idryomov@redhat.com>

mark session as readonly and wake up all cap waiters.
Signed-off-by: Yan, Zheng <zyan@redhat.com>

Signed-off-by: Ilya Dryomov <idryomov@redhat.com>

On Mon, Dec 22, 2014 at 5:35 PM, Sage Weil <sage@newdream.net> wrote:
> On Mon, 22 Dec 2014, Ilya Dryomov wrote:
>> Actually, pool op stuff has been unused for over two years - looks like
>> it was added for rbd create_snap and that got ripped out in 2012.  It's
>> unlikely we'd ever need to manage pools or snaps from the kernel client
>> so I think it makes sense to nuke it.  Sage?
>
> Yep!
Signed-off-by: Ilya Dryomov <idryomov@redhat.com>

Pull nios2 fix from Ley Foon Tan:
 "This fixes incorrect behavior of some user programs"

* tag 'nios2-fixes-v3.19-final' of git://git.rocketboards.org/linux-socfpga-next:
  nios2: fix unhandled signals

Pull aio nested sleep annotation from Ben LaHaise,

* git://git.kvack.org/~bcrl/aio-fixes:
  aio: annotate aio_read_event_ring for sleep patterns

Merge tag 'trace-fixes-v3.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull ftrace fixes from Steven Rostedt:
 "During testing Sedat Dilek hit a "suspicious RCU usage" splat that
  pointed out a real bug.  During suspend and resume the tlb_flush
  tracepoint is called when the CPU is going offline.  As the CPU has
  been noted as offline, RCU is ignoring that CPU, which means that it
  can not use RCU protected locks.  When tracepoints are activated, they
  require RCU locking, and if RCU is ignoring a CPU that runs a
  tracepoint, there is a chance that the tracepoint could cause
  corruption.

  The solution was to change the tracepoint into a
  TRACE_EVENT_CONDITION() which allows us to check a condition to
  determine if the tracepoint should be called or not.  If the condition
  is not met, the rcu protected code will not be executed.  By adding
  the condition "cpu_online(smp_processor_id())", this will prevent the
  RCU protected code from being executed if the CPU is marked offline.

  After adding this, another bug was discovered.  As RCU checks rcu
  callers, if a rcu call is not done, there is no check (obviously).  We
  found that tracepoints could be added in RCU ignored locations and not
  have lockdep complain until the tracepoint is activated.  This missed
  places where tracepoints were added in places they should not have
  been.  To fix this, code was added in 3.18 that if lockdep is enabled,
  any tracepoint will still call the rcu checks even if the tracepoint
  is not enabled.  The bug here, is that the check does not take the
  CONDITION into account.  As the condition may prevent tracepoints from
  being activated in RCU ignored areas (as the one patch does), we get
  false positives when we enable lockdep and hit a tracepoint that the
  condition prevents it from being called in a RCU ignored location.

  The fix for this is to add the CONDITION to the rcu checks, even if
  the tracepoint is not enabled"

* tag 'trace-fixes-v3.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  x86/tlb/trace: Do not trace on CPU that is offline
  tracing: Add condition check to RCU lockdep checks

Follow other architectures for user fault handling.
Signed-off-by: Chung-Ling Tang <cltang@codesourcery.com>
Acked-by: Ley Foon Tan <lftan@altera.com>

When taking a CPU down for suspend and resume, a tracepoint may be called
when the CPU has been designated offline. As tracepoints require RCU for
protection, they must not be called if the current CPU is offline.

Unfortunately, trace_tlb_flush() is called in this scenario as was noted
by LOCKDEP:

...

 Disabling non-boot CPUs ...
 intel_pstate CPU 1 exiting

 ===============================
 smpboot: CPU 1 didn't die...
 [ INFO: suspicious RCU usage. ]
 3.19.0-rc7-next-20150204.1-iniza-small #1 Not tainted
 -------------------------------
 include/trace/events/tlb.h:35 suspicious rcu_dereference_check() usage!

 other info that might help us debug this:

 RCU used illegally from offline CPU!
 rcu_scheduler_active = 1, debug_locks = 0
 no locks held by swapper/1/0.

 stack backtrace:
 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 3.19.0-rc7-next-20150204.1-iniza-small #1
 Hardware name: SAMSUNG ELECTRONICS CO., LTD. 530U3BI/530U4BI/530U4BH/530U3BI/530U4BI/530U4BH, BIOS 13XK 03/28/2013
  0000000000000001 ffff88011a44fe18 ffffffff817e370d 0000000000000011
  ffff88011a448290 ffff88011a44fe48 ffffffff810d6847 ffff8800c66b9600
  0000000000000001 ffff88011a44c000 ffffffff81cb3900 ffff88011a44fe78
 Call Trace:
  [<ffffffff817e370d>] dump_stack+0x4c/0x65
  [<ffffffff810d6847>] lockdep_rcu_suspicious+0xe7/0x120
  [<ffffffff810b71a5>] idle_task_exit+0x205/0x2c0
  [<ffffffff81054c4e>] play_dead_common+0xe/0x50
  [<ffffffff81054ca5>] native_play_dead+0x15/0x140
  [<ffffffff8102963f>] arch_cpu_idle_dead+0xf/0x20
  [<ffffffff810cd89e>] cpu_startup_entry+0x37e/0x580
  [<ffffffff81053e20>] start_secondary+0x140/0x150
 intel_pstate CPU 2 exiting

...

By converting the tlb_flush tracepoint to a TRACE_EVENT_CONDITION where the
condition is cpu_online(smp_processor_id()), we can avoid calling RCU protected
code when the CPU is offline.

Link: http://lkml.kernel.org/r/CA+icZUUGiGDoL5NU8RuxKzFjoLjEKRtUWx=JB8B9a0EQv-eGzQ@mail.gmail.com

Cc: stable@vger.kernel.org # 3.17+
Fixes: d17d8f9d "x86/mm: Add tracepoints for TLB flushes"
Reported-by: Sedat Dilek <sedat.dilek@gmail.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Suggested-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Hansen <dave@sr71.net>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

The trace_tlb_flush() tracepoint can be called when a CPU is going offline.
When a CPU is offline, RCU is no longer watching that CPU and since the
tracepoint is protected by RCU, it must not be called. To prevent the
tlb_flush tracepoint from being called when the CPU is offline, it was
converted to a TRACE_EVENT_CONDITION where the condition checks if the
CPU is online before calling the tracepoint.

Unfortunately, this was not enough to stop lockdep from complaining about
it. Even though the RCU protected code of the tracepoint will never be
called, the condition is hidden within the tracepoint, and even though the
condition prevents RCU code from being called, the lockdep checks are
outside the tracepoint (this is to test tracepoints even when they are not
enabled).

Even though tracepoints should be checked to be RCU safe when they are not
enabled, the condition should still be considered when checking RCU.

Link: http://lkml.kernel.org/r/CA+icZUUGiGDoL5NU8RuxKzFjoLjEKRtUWx=JB8B9a0EQv-eGzQ@mail.gmail.com

Fixes: 3a630178 "tracing: generate RCU warnings even when tracepoints are disabled"
Cc: stable@vger.kernel.org # 3.18+
Acked-by: Dave Hansen <dave@sr71.net>
Reported-by: Sedat Dilek <sedat.dilek@gmail.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

Pull one more infiniband revert from Roland Dreier:
 "One more last-second RDMA change for 3.19: Yann realized that the
  previous revert of new userspace ABI did not go far enough, and we're
  still exposing a change that we don't want.  Revert even closer to
  3.18 interface to make sure we get things right in the long run"

Yann Droneaud pipes up:
 "I hope this could go in v3.19 as, at this stage, we don't want to
  expose any bits of this ABI in a released kernel"

* tag 'rdma-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband:
  Revert "IB/core: Add support for extended query device caps"

Pull btrfs fix from Chris Mason:
 "Forrest Liu tracked down a missing blk_finish_plug in the btrfs
  logging code.  This isn't a new bug, and it's hard to hit.  But, it's
  safe enough for inclusion now, and in my for-linus branch"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: add missing blk_finish_plug in btrfs_sync_log()

Merge branches 'timers-urgent-for-linus' and 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer and x86 fix from Ingo Molnar:
 "A CLOCK_TAI early expiry fix and an x86 microcode driver oops fix"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  hrtimer: Fix incorrect tai offset calculation for non high-res timer systems

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, microcode: Return error from driver init code when loader is disabled

Pull scheduler fixes from Ingo Molnar:
 "Misc fixes"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/deadline: Fix deadline parameter modification handling
  sched/wait: Remove might_sleep() from wait_event_cmd()
  sched: Fix crash if cpuset_cpumask_can_shrink() is passed an empty cpumask
  sched/fair: Avoid using uninitialized variable in preferred_group_nid()

Pull core kernel fixes from Ingo Molnar:
 "Two liblockdep fixes and a CPU hotplug race fix"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tools/liblockdep: don't include host headers
  tools/liblockdep: ignore generated .so file
  smpboot: Add missing get_online_cpus() in smpboot_register_percpu_thread()

Pull sound fixes from Takashi Iwai:
 "Hopefully the final pull request for 3.19: this ended up with a
  slightly higher volume than wished, but I put them all as they are
  either stable or 3.19 regression fixes.

  Most of commits are from ASoC, and have been stewed for a while in
  linux-next.  The only change in the common code is the regression
  fixes for ASoC AC97 stuff wrt device registrations.  The rest are
  device-specific, mostly small fixes in various ASoC drivers and ak411x
  on ice1724 boards"

* tag 'sound-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ASoC: Intel: fix sst firmware path for cht-bsw-rt5672
  ARM: dts: Fix I2S1, I2S2 compatible for exynos4 SoCs
  ASoC: sgtl5000: add delay before first I2C access
  MAINTAINERS: ASoC: add maintainer for Intel BDW/HSW ASoC driver
  ASoC: atmel_ssc_dai: fix the setting for DSP mode
  ASoC: sgtl5000: Use shift mask when setting codec mode
  ASoC: tlv320aic3x: Fix data delay configuration
  ALSA: ak411x: Fix stall in work callback
  ASoC: Intel: Used lock version to update shim registers
  ASoC: wm8731: init mutex in i2c init path
  ASoC: atmel_ssc_dai: fix start event for I2S mode
  ASoC: rt5640: Add RT5642 ACPI ID for Intel Baytrail
  ASoC: wm97xx: Reset AC'97 device before registering it
  ASoC: Add support for allocating AC'97 device before registering it

Merge misc fixes from Andrew Morton:
 "7 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm/debug_pagealloc: fix build failure on ppc and some other archs
  nilfs2: fix deadlock of segment constructor over I_SYNC flag
  MAINTAINERS: remove SUPERH website
  memcg, shmem: fix shmem migration to use lrucare
  mm: export "high_memory" symbol on !MMU
  .mailmap: update Konstantin Khlebnikov's email address
  mm: pagewalk: call pte_hole() for VM_PFNMAP during walk_page_range

Pull MIPS fixes from Ralf Baechle:
 "The pending MIPS fixes for 3.19.  All across the field and nothing
  particularly severe or dramatic"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (23 commits)
  IRQCHIP: mips-gic: Avoid rerouting timer IRQs for smp-cmp
  MIPS: Fix syscall_get_nr for the syscall exit tracing.
  MIPS: elf2ecoff: Ignore PT_MIPS_ABIFLAGS program headers.
  MIPS: elf2ecoff: Rewrite main processing loop to switch.
  MIPS: fork: Fix MSA/FPU/DSP context duplication race
  MIPS: Fix C0_Pagegrain[IEC] support.
  MIPS: traps: Fix inline asm ctc1 missing .set hardfloat
  MIPS: mipsregs.h: Add write_32bit_cp1_register()
  MIPS: Fix kernel lockup or crash after CPU offline/online
  MIPS: OCTEON: fix kernel crash when offlining a CPU
  MIPS: ARC: Fix build error.
  MIPS: IRQ: Fix disable_irq on CPU IRQs
  MIPS: smp-mt,smp-cmp: Enable all HW IRQs on secondary CPUs
  MIPS: Fix restart of indirect syscalls
  MIPS: ELF: fix loading o32 binaries on 64-bit kernels
  MIPS: mips-cm: Fix sparse warnings
  MIPS: Kconfig: Fix recursive dependency.
  MIPS: Compat: Fix build error if CONFIG_MIPS32_COMPAT but no compat ABI.
  MIPS: JZ4740: Fixup #include's (sparse)
  MIPS: Wire up execveat(2).
  ...

While commit 7e36ef82 ("IB/core: Temporarily disable
ex_query_device uverb") is correct as it makes the extended
QUERY_DEVICE uverb (which came as part of commit 5a77abf9
("IB/core: Add support for extended query device caps") and commit
860f10a7 ("IB/core: Add flags for on demand paging support")) not
available to userspace, it doesn't address the initial issue regarding
ib_copy_to_udata() [1][2].

Additionally, further discussions around this new uverb seems to
conclude it would require a different data structure than the one
currently described in <rdma/ib_user_verbs.h> [3].

Both of these issues require a revert of the changes, so this patch
partially reverts commit 8cdd312c ("IB/mlx5: Implement the ODP
capability query verb") and commit 860f10a7 ("IB/core: Add flags
for on demand paging support") and fully reverts commit 5a77abf9
("IB/core: Add support for extended query device caps").

[1] "Re: [PATCH v3 06/17] IB/core: Add support for extended query device caps"
    http://mid.gmane.org/1418733236.2779.26.camel@opteya.com

[2] "Re: [PATCH] IB/core: Temporarily disable ex_query_device uverb"
    http://mid.gmane.org/1423067503.3030.83.camel@opteya.com

[3] "RE: [PATCH v1 1/5] IB/uverbs: ex_query_device: answer must not depend on request's comp_mask"
    http://mid.gmane.org/2807E5FD2F6FDA4886F6618EAC48510E0CC12C30@CRSMSX101.amr.corp.intel.com

Cc: Eli Cohen <eli@mellanox.com>
Cc: Haggai Eran <haggaie@mellanox.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Shachar Raindel <raindel@mellanox.com>
Signed-off-by: Yann Droneaud <ydroneaud@opteya.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

Kim Phillips reported following build failure.

  LD      init/built-in.o
  mm/built-in.o: In function `free_pages_prepare':
  mm/page_alloc.c:770: undefined reference to `.kernel_map_pages'
  mm/built-in.o: In function `prep_new_page':
  mm/page_alloc.c:933: undefined reference to `.kernel_map_pages'
  mm/built-in.o: In function `map_pages':
  mm/compaction.c:61: undefined reference to `.kernel_map_pages'
  make: *** [vmlinux] Error 1

Reason for this problem is that commit 031bc574
("mm/debug-pagealloc: make debug-pagealloc boottime configurable")
forgot to remove the old declaration of kernel_map_pages() for some
architectures.  This patch removes them to fix build failure.
Reported-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: David Miller <davem@davemloft.net>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>