Now that all external cgroup_lock() users are gone, we can finally
unexport the locking interface and prevent future abuse of
cgroup_mutex.

Make cgroup_[un]lock() and cgroup_lock_live_group() static.  Also,
cgroup_attach_task() doesn't have any user left and can't be used
without locking interface anyway.  Make it static too.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>

cgroup_lock_live_group() and cgroup_attach_task() are scheduled to be
made static.  Relocate the former and cgroup_attach_task_all() so that
we don't need forward declarations.

This patch is pure relocation.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>

When a cpuset becomes empty (no CPU or memory), its tasks are
transferred with the nearest ancestor with execution resources.  This
is implemented using cgroup_scan_tasks() with a callback which grabs
cgroup_mutex and invokes cgroup_attach_task() on each task.

Both cgroup_mutex and cgroup_attach_task() are scheduled to be
unexported.  Implement cgroup_transfer_tasks() in cgroup proper which
is essentially the same as move_member_tasks_to_cpuset() except that
it takes cgroups instead of cpusets and @to comes before @from like
normal functions with those arguments, and replace
move_member_tasks_to_cpuset() with it.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>

As cgroup supports rename, it's unsafe to dereference dentry->d_name
without proper vfs locks. Fix this by using cgroup_name() rather than
dentry directly.

Also open code memcg_cache_name because it is called only from
kmem_cache_dup which frees the returned name right after
kmem_cache_create_memcg makes a copy of it. Such a short-lived
allocation doesn't make too much sense. So replace it by a static
buffer as kmem_cache_dup is called with memcg_cache_mutex.
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Glauber Costa <glommer@parallels.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

This patch removes unused parameter from cgroup_task_migrate().
Signed-off-by: Kevin Wilson <wkevils@gmail.com>
Acked-by: Acked-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

This trivial patch removes a word which appears twice in
Documentation/cgroup/cgroup.txt.
Signed-off-by: Rami Rosen <ramirose@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

These two functions share most of the code.
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

This patch makes exception changes to propagate down in hierarchy respecting
when possible local exceptions.

New exceptions allowing additional access to devices won't be propagated, but
it'll be possible to add an exception to access all of part of the newly
allowed device(s).

New exceptions disallowing access to devices will be propagated down and the
local group's exceptions will be revalidated for the new situation.
Example:
      A
     / \
        B

    group        behavior          exceptions
    A            allow             "b 8:* rwm", "c 116:1 rw"
    B            deny              "c 1:3 rwm", "c 116:2 rwm", "b 3:* rwm"

If a new exception is added to group A:
	# echo "c 116:* r" > A/devices.deny
it'll propagate down and after revalidating B's local exceptions, the exception
"c 116:2 rwm" will be removed.

In case parent's exceptions change and local exceptions are not allowed anymore,
they'll be deleted.

v7:
- do not allow behavior change when the cgroup has children
- update documentation

v6: fixed issues pointed by Serge Hallyn
- only copy parent's exceptions while propagating behavior if the local
  behavior is different
- while propagating exceptions, do not clear and copy parent's: it'd be against
  the premise we don't propagate access to more devices

v5: fixed issues pointed by Serge Hallyn
- updated documentation
- not propagating when an exception is written to devices.allow
- when propagating a new behavior, clean the local exceptions list if they're
  for a different behavior

v4: fixed issues pointed by Tejun Heo
- separated function to walk the tree and collect valid propagation targets

v3: fixed issues pointed by Tejun Heo
- update documentation
- move css_online/css_offline changes to a new patch
- use cgroup_for_each_descendant_pre() instead of own descendant walk
- move exception_copy rework to a separared patch
- move exception_clean rework to a separated patch

v2: fixed issues pointed by Tejun Heo
- instead of keeping the local settings that won't apply anymore, remove them

Cc: Tejun Heo <tj@kernel.org>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Aristeu Rozanski <aris@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

Allocate resources and change behavior only when online. This is needed in
order to determine if a node is suitable for hierarchy propagation or if it's
being removed.

Locking:
Both functions take devcgroup_mutex to make changes to device_cgroup structure.
Hierarchy propagation will also take devcgroup_mutex before walking the
tree while walking the tree itself is protected by rcu lock.
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Aristeu Rozanski <aris@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

Currently may_access() is only able to verify if an exception is valid for the
current cgroup, which has the same behavior. With hierarchy, it'll be also used
to verify if a cgroup local exception is valid towards its cgroup parent, which
might have different behavior.

v2:
- updated patch description
- rebased on top of a new patch to expand the may_access() logic to make it
  more clear
- fixed argument description order in may_access()
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Aristeu Rozanski <aris@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

In order to make the next patch more clear, expand may_access() logic.

v2: may_access() returns bool now
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Aristeu Rozanski <aris@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

The 3rd parameter of flex_array_prealloc() is the number of elements,
not the index of the last element.

The effect of the bug is, when opening cgroup.procs, a flex array will
be allocated and all elements of the array is allocated with
GFP_KERNEL flag, but the last one is GFP_ATOMIC, and if we fail to
allocate memory for it, it'll trigger a BUG_ON().
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org

eventfd_poll() never returns POLLHUP.
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

When we open cgroup.procs, we'll allocate an buffer and store all tasks'
tgid in it, and then duplicate entries will be stripped. If that results
in a much smaller pid list, we'll re-allocate a smaller buffer.

But we've already sucessfully allocated memory and reading the procs
file is a short period and the memory will be freed very soon, so why
bother to re-allocate memory.
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

cpuset no longer nests cgroup_mutex inside cpu_hotplug lock, so
we don't have to release cgroup_mutex before calling css_offline().
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

It was used by ns cgroup, and ns cgroup was removed long ago.
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

Sasha reported a lockdep warning when OOM was triggered. The reason
is cgroup_name() should be called with rcu_read_lock() held.
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

We don't need to include cgroup.h in cpuset.h.
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

It's not needed at all.
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

subsys[i] is set to NULL in cgroup_unload_subsys() at modular unload,
and that's protected by cgroup_mutex, and then the memory *subsys[i]
resides will be freed.

So this is unsafe without any locking:

  if (!ss || ss->module)
  ...

v2:
- add a comment for enum cgroup_subsys_id
- simplify the comment in cgroup_exit()
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

We no longer fail rmdir() when there're still css refs, so we don't
need to check css refs in check_for_release().

This also voids a bug. cgroup_has_css_refs() accesses subsys[i]
without cgroup_mutex, so it can race with cgroup_unload_subsys().

cgroup_has_css_refs()
...
  if (ss == NULL || ss->root != cgrp->root)

if ss pointers to net_cls_subsys, and cls_cgroup module is unloaded
right after the former check but before the latter, the memory that
net_cls_subsys resides has become invalid.
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

Use cgroup_name() instead of cgrp->dentry->name. This makes the code
a bit simpler.

While at it, remove cpuset_name and make cpuset_nodelist a local variable
to cpuset_print_task_mems_allowed().
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

rename() will change dentry->d_name. The result of this race can
be worse than seeing partially rewritten name, but we might access
a stale pointer because rename() will re-allocate memory to hold
a longer name.

As accessing dentry->name must be protected by dentry->d_lock or
parent inode's i_mutex, while on the other hand cgroup-path() can
be called with some irq-safe spinlocks held, we can't generate
cgroup path using dentry->d_name.

Alternatively we make a copy of dentry->d_name and save it in
cgrp->name when a cgroup is created, and update cgrp->name at
rename().

v5: use flexible array instead of zero-size array.
v4: - allocate root_cgroup_name and all root_cgroup->name points to it.
    - add cgroup_name() wrapper.
v3: use kfree_rcu() instead of synchronize_rcu() in user-visible path.
v2: make cgrp->name RCU safe.
Signed-off-by: Li Zefan <lizefan@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

Pull fbdev UAPI disintegration from David Howells:
 "You'll be glad to here that the end is nigh for the UAPI patches.
  Only the fbdev/framebuffer piece remains now that the SCSI stuff has
  gone in.

  Here are the UAPI disintegration bits for the fbdev drivers.  It
  appears that Florian hasn't had time to deal with my patch, but back
  in December he did say he didn't mind if I pushed it forward."

Yay.  No more uapi movement.  And hopefully no more big header file
cleanups coming up either, it just tends to be very painful.

* tag 'disintegrate-fbdev-20121220' of git://git.infradead.org/users/dhowells/linux-headers:
  UAPI: (Scripted) Disintegrate include/video

Merge tag 'stable/for-linus-3.9-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Pull Xen bug-fixes from Konrad Rzeszutek Wilk:
 - Update the Xen ACPI memory and CPU hotplug locking mechanism.
 - Fix PAT issues wherein various applications would not start
 - Fix handling of multiple MSI as AHCI now does it.
 - Fix ARM compile failures.

* tag 'stable/for-linus-3.9-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xenbus: fix compile failure on ARM with Xen enabled
  xen/pci: We don't do multiple MSI's.
  xen/pat: Disable PAT using pat_enabled value.
  xen/acpi: xen cpu hotplug minor updates
  xen/acpi: xen memory hotplug minor updates

Pull  more VFS bits from Al Viro:
 "Unfortunately, it looks like xattr series will have to wait until the
  next cycle ;-/

  This pile contains 9p cleanups and fixes (races in v9fs_fid_add()
  etc), fixup for nommu breakage in shmem.c, several cleanups and a bit
  more file_inode() work"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  constify path_get/path_put and fs_struct.c stuff
  fix nommu breakage in shmem.c
  cache the value of file_inode() in struct file
  9p: if v9fs_fid_lookup() gets to asking server, it'd better have hashed dentry
  9p: make sure ->lookup() adds fid to the right dentry
  9p: untangle ->lookup() a bit
  9p: double iput() in ->lookup() if d_materialise_unique() fails
  9p: v9fs_fid_add() can't fail now
  v9fs: get rid of v9fs_dentry
  9p: turn fid->dlist into hlist
  9p: don't bother with private lock in ->d_fsdata; dentry->d_lock will do just fine
  more file_inode() open-coded instances
  selinux: opened file can't have NULL or negative ->f_path.dentry

(In the meantime, the hlist traversal macros have changed, so this
required a semantic conflict fixup for the newly hlistified fid->dlist)

Pull btrfs fixup from Chris Mason:
 "Geert and James both sent this one in, sorry guys"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  btrfs/raid56: Add missing #include <linux/vmalloc.h>

Pull second set of s390 patches from Martin Schwidefsky:
 "The main part of this merge are Heikos uaccess patches.  Together with
  commit 09884964 ("mm: do not grow the stack vma just because of an
  overrun on preceding vma") the user string access is hopefully fixed
  for good.

  In addition some bug fixes and two cleanup patches."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/module: fix compile warning
  qdio: remove unused parameters
  s390/uaccess: fix kernel ds access for page table walk
  s390/uaccess: fix strncpy_from_user string length check
  input: disable i8042 PC Keyboard controller for s390
  s390/dis: Fix invalid array size
  s390/uaccess: remove pointless access_ok() checks
  s390/uaccess: fix strncpy_from_user/strnlen_user zero maxlen case
  s390/uaccess: shorten strncpy_from_user/strnlen_user
  s390/dasd: fix unresponsive device after all channel paths were lost
  s390/mm: ignore change bit for vmemmap
  s390/page table dumper: add support for change-recording override bit

Merge branch 'fixes-for-3.9-latest' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux

Pull second round of PARISC updates from Helge Deller:
 "The most important fix in this branch is the switch of io_setup,
  io_getevents and io_submit syscalls to use the available compat
  syscalls when running 32bit userspace on 64bit kernel.  Other than
  that it's mostly removal of compile warnings."

* 'fixes-for-3.9-latest' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: fix redefinition of SET_PERSONALITY
  parisc: do not install modules when installing kernel
  parisc: fix compile warnings triggered by atomic_sub(sizeof(),v)
  parisc: check return value of down_interruptible() in hp_sdc_rtc.c
  parisc: avoid unitialized variable warning in pa_memcpy()
  parisc: remove unused variable 'compat_val'
  parisc: switch to compat_functions of io_setup, io_getevents and io_submit
  parisc: select ARCH_WANT_FRAME_POINTERS

Pull new ImgTec Meta architecture from James Hogan:
 "This adds core architecture support for Imagination's Meta processor
  cores, followed by some later miscellaneous arch/metag cleanups and
  fixes which I kept separate to ease review:

   - Support for basic Meta 1 (ATP) and Meta 2 (HTP) core architecture
   - A few fixes all over, particularly for symbol prefixes
   - A few privilege protection fixes
   - Several cleanups (setup.c includes, split out a lot of
     metag_ksyms.c)
   - Fix some missing exports
   - Convert hugetlb to use vm_unmapped_area()
   - Copy device tree to non-init memory
   - Provide dma_get_sgtable()"

* tag 'metag-v3.9-rc1-v4' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag: (61 commits)
  metag: Provide dma_get_sgtable()
  metag: prom.h: remove declaration of metag_dt_memblock_reserve()
  metag: copy devicetree to non-init memory
  metag: cleanup metag_ksyms.c includes
  metag: move mm/init.c exports out of metag_ksyms.c
  metag: move usercopy.c exports out of metag_ksyms.c
  metag: move setup.c exports out of metag_ksyms.c
  metag: move kick.c exports out of metag_ksyms.c
  metag: move traps.c exports out of metag_ksyms.c
  metag: move irq enable out of irqflags.h on SMP
  genksyms: fix metag symbol prefix on crc symbols
  metag: hugetlb: convert to vm_unmapped_area()
  metag: export clear_page and copy_page
  metag: export metag_code_cache_flush_all
  metag: protect more non-MMU memory regions
  metag: make TXPRIVEXT bits explicit
  metag: kernel/setup.c: sort includes
  perf: Enable building perf tools for Meta
  metag: add boot time LNKGET/LNKSET check
  metag: add __init to metag_cache_probe()
  ...

Pull late ARM updates from Russell King:
 "Here is the late set of ARM updates for this merge window; in here is:

   - The ARM parts of the broadcast timer support, core parts merged
     through tglx's tree.  This was left over from the previous merge to
     allow the dependency on tglx's tree to be resolved.

   - A fix to the VFP code which shows up on Raspberry Pi's, as well as
     fixing the fallout from a previous commit in this area.

   - A number of smaller fixes scattered throughout the ARM tree"

* 'for-linus' of git://git.linaro.org/people/rmk/linux-arm:
  ARM: Fix broken commit 0cc41e4a corrupting kernel messages
  ARM: fix scheduling while atomic warning in alignment handling code
  ARM: VFP: fix emulation of second VFP instruction
  ARM: 7656/1: uImage: Error out on build of multiplatform without LOADADDR
  ARM: 7640/1: memory: tegra_ahb_enable_smmu() depends on TEGRA_IOMMU_SMMU
  ARM: 7654/1: Preserve L_PTE_VALID in pte_modify()
  ARM: 7653/2: do not scale loops_per_jiffy when using a constant delay clock
  ARM: 7651/1: remove unused smp_timer_broadcast #define

Pull char/misc patch from Greg Kroah-Hartman:
 "Here is one remaining patch for 3.9-rc1.  It is for the hyper-v
  drivers, and had to wait until some other patches went in through the
  x86 tree."
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

* tag 'char-misc-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  Drivers: hv: vmbus: Use the new infrastructure for delivering VMBUS interrupts

Pull USB patch revert from Greg Kroah-Hartman:
 "Here is one remaining USB patch for 3.9-rc1, it reverts a 3.8 patch
  that has caused a lot of regressions for some VIA EHCI controllers."

* tag 'usb-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  USB: EHCI: revert "remove ASS/PSS polling timeout"

Pull watchdog updates from Wim Van Sebroeck:
 "This contains:
   - fixes and improvements
   - devicetree bindings
   - conversion to watchdog generic framework of the following drivers:
        - booke_wdt
        - bcm47xx_wdt.c
        - at91sam9_wdt
   - Removal of old STMP3xxx driver
   - Addition of following new drivers:
        - new driver for STMP3xxx and i.MX23/28
        - Retu watchdog driver"

* git://www.linux-watchdog.org/linux-watchdog: (30 commits)
  watchdog: sp805_wdt depends on ARM
  watchdog: davinci_wdt: update to devm_* API
  watchdog: davinci_wdt: use devm managed clk get
  watchdog: at91rm9200: add DT support
  watchdog: add timeout-sec property binding
  watchdog: at91sam9_wdt: Convert to use the watchdog framework
  watchdog: omap_wdt: Add option nowayout
  watchdog: core: dt: add support for the timeout-sec dt property
  watchdog: bcm47xx_wdt.c: add hard timer
  watchdog: bcm47xx_wdt.c: rename wdt_time to timeout
  watchdog: bcm47xx_wdt.c: rename ops methods
  watchdog: bcm47xx_wdt.c: use platform device
  watchdog: bcm47xx_wdt.c: convert to watchdog core api
  watchdog: Convert BookE watchdog driver to watchdog infrastructure
  watchdog: s3c2410_wdt: Use devm_* functions
  watchdog: remove old STMP3xxx driver
  watchdog: add new driver for STMP3xxx and i.MX23/28
  rtc: stmp3xxx: add wdt-accessor function
  watchdog: introduce retu_wdt driver
  watchdog: intel_scu_watchdog: fix Kconfig dependency
  ...

Pull second set of slave-dmaengine updates from Vinod Koul:
 "Arnd's patch moves the dw_dmac to use generic DMA binding.  I agreed
  to merge this late as it will avoid the conflicts between trees.

  The second patch from Matt adding a dma_request_slave_channel_compat
  API was supposed to be picked up, but somehow never got picked up.
  Some patches dependent on this are already in -next :("

* 'next' of git://git.infradead.org/users/vkoul/slave-dma:
  dmaengine: dw_dmac: move to generic DMA binding
  dmaengine: add dma_request_slave_channel_compat()

Pull x86 platform driver updates from Matthew Garrett:
 "Mostly relatively small updates, along with some hardware enablement
  for Sony hardware and a pile of updates to Google's Chromebook driver"

* 'for_linus' of git://cavan.codon.org.uk/platform-drivers-x86: (49 commits)
  ideapad-laptop: Depend on BACKLIGHT_CLASS_DEVICE instead of selecting it
  ideapad: depends on backlight subsystem and update comment
  Platform: x86: chromeos_laptop - add i915 gmbuses to adapter names
  Platform: x86: chromeos_laptop - Add isl light sensor for Pixel
  Platform: x86: chromeos_laptop - Add a more general add_i2c_device
  Platform: x86: chromeos_laptop - Add Pixel Touchscreen
  Platform: x86: chromeos_laptop - Add support for probing devices
  Platform: x86: chromeos_laptop - Add Pixel Trackpad
  hp-wmi: fix handling of platform device
  sony-laptop: leak in error handling sony_nc_lid_resume_setup()
  hp-wmi: Add support for SMBus hotkeys
  asus-wmi: Fix unused function build warning
  acer-wmi: avoid the warning of 'devices' may be used uninitialized
  drivers/platform/x86/thinkpad_acpi.c: Handle HKEY event 0x6040
  Platform: x86: chromeos_laptop - Add HP Pavilion 14
  Platform: x86: chromeos_laptop - Add Taos tsl2583 device
  Platform: x86: chromeos_laptop - Add Taos tsl2563 device
  Platform: x86: chromeos_laptop - Add Acer C7 trackpad
  Platform: x86: chromeos_laptop - Rename setup_lumpy_tp to setup_cyapa_smbus_tp
  asus-laptop: always report brightness key events
  ...

tilegx_defconfig:

fs/btrfs/raid56.c: In function 'btrfs_alloc_stripe_hash_table':
fs/btrfs/raid56.c:206:3: error: implicit declaration of function 'vzalloc' [-Werror=implicit-function-declaration]
fs/btrfs/raid56.c:206:9: warning: assignment makes pointer from integer without a cast [enabled by default]
fs/btrfs/raid56.c:226:4: error: implicit declaration of function 'vfree' [-Werror=implicit-function-declaration]
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

Pull ext4 bug fixes from Ted Ts'o:
 "Various bug fixes for ext4.  The most important is a fix for the new
  extent cache's slab shrinker which can cause significant, user-visible
  pauses when the system is under memory pressure."

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: enable quotas before orphan cleanup
  ext4: don't allow quota mount options when quota feature enabled
  ext4: fix a warning from sparse check for ext4_dir_llseek
  ext4: convert number of blocks to clusters properly
  ext4: fix possible memory leak in ext4_remount()
  jbd2: fix ERR_PTR dereference in jbd2__journal_start
  ext4: use percpu counter for extent cache count
  ext4: optimize ext4_es_shrink()