This patch introduce macro __cp_payload.
Signed-off-by: NWanpeng Li <wanpeng.li@linux.intel.com>
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch introduces a generic ioctl for fs shutdown, which was used by xfs.

If this shutdown is triggered, filesystem stops any further IOs according to the
following options.

1. FS_GOING_DOWN_FULLSYNC
 : this will flush all the data and dentry blocks, and do checkpoint before
   shutdown.

2. FS_GOING_DOWN_METASYNC
 : this will do checkpoint before shutdown.

3. FS_GOING_DOWN_NOSYNC
 : this will trigger shutdown as is.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

During the roll-forward recovery, -ENOENT for f2fs_iget can be skipped.
So, this error value should not be propagated.
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch removes obsolete code in which summary variable is not needed.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

We update extent cache for all user inode of f2fs including dir inode, so this
patch gives another chance to try to get physical address of page from extent
cache for dir inode.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch switch to check FI_NO_EXTENT in f2fs_{lookup,update}_extent_cache
instead of f2fs_{lookup,update}_extent_tree or {lookup,update}_extent_info.

No functionality modification in this patch.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds a fast lookup path for rb-tree extent cache.

In this patch we add a recently accessed extent node pointer 'cached_en' in
extent tree. In lookup path of extent cache, we will firstly lookup the last
accessed extent node which cached_en points, if we do not hit in this node,
we will try to lookup extent node in rb-tree.

By this way we can avoid unnecessary slow lookup in rb-tree sometimes.

Note that, side-effect of this patch is that we will increase memory cost,
because we will store a pointer variable in each struct extent tree
additionally.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds trace for lookup/update/shrink/destroy ops in rb-tree extent cache.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch add and show stat info of total memory footprint for extent tree,node
in debugfs.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch enables rb-tree based extent cache in f2fs.

When we mount with "-o extent_cache", f2fs will try to add recently accessed
page-block mappings into rb-tree based extent cache as much as possible, instead
of original one extent info cache.

By this way, f2fs can support more effective cache between dnode page cache and
disk. It will supply high hit ratio in the cache with fewer memory when dnode
page cache are reclaimed in environment of low memory.

Storage: Sandisk sd card 64g
1.append write file (offset: 0, size: 128M);
2.override write file (offset: 2M, size: 1M);
3.override write file (offset: 4M, size: 1M);
...
4.override write file (offset: 48M, size: 1M);
...
5.override write file (offset: 112M, size: 1M);
6.sync
7.echo 3 > /proc/sys/vm/drop_caches
8.read file (size:128M, unit: 4k, count: 32768)
(time dd if=/mnt/f2fs/128m bs=4k count=32768)

Extent Hit Ratio:
		before		patched
Hit Ratio	121 / 1071	1071 / 1071

Performance:
		before		patched
real    	0m37.051s	0m35.556s
user    	0m0.040s	0m0.026s
sys     	0m2.990s	0m2.251s

Memory Cost:
		before		patched
Tree Count:	0		1 (size: 24 bytes)
Node Count:	0		45 (size: 1440 bytes)

v3:
 o retest and given more details of test result.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds a mount option 'extent_cache' in f2fs.

It is try to use a rb-tree based extent cache to cache more mapping information
with less memory if this option is set, otherwise we will use the original one
extent info cache.
Suggested-by: NChangman Lee <cm224.lee@samsung.com>
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds core functions including slab cache init function and
init/lookup/update/shrink/destroy function for rb-tree based extent cache.

Thank Jaegeuk Kim and Changman Lee as they gave much suggestion about detail
design and implementation of extent cache.

Todo:
 * register rb-based extent cache shrink with mm shrink interface.

v2:
 o move set_extent_info and __is_{extent,back,front}_mergeable into f2fs.h.
 o introduce __{attach,detach}_extent_node for code readability.
 o add cond_resched() when fail to invoke kmem_cache_alloc/radix_tree_insert.
 o fix some coding style and typo issues.

v3:
 o fix oops due to using an unassigned pointer.
 o use list_del to remove extent node in shrink list.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NChangman Lee <cm224.lee@samsung.com>
[Jaegeuk Kim: add static for some funcitons and declare in f2fs.h]
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Introduce infra macro and data structure for rb-tree based extent cache:

Macros:
 * EXT_TREE_VEC_SIZE: indicate vector size for gang lookup in extent tree.
 * F2FS_MIN_EXTENT_LEN: indicate minimum length of extent managed in cache.
 * EXTENT_CACHE_SHRINK_NUMBER: indicate number of extent in cache will be shrunk.

Basic data structures for extent cache:
 * struct extent_tree: extent tree entry per inode.
 * struct extent_node: extent info node linked in extent tree.

Besides, adding new extent cache related fields in f2fs_sb_info.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NChangman Lee <cm224.lee@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

In this patch, we do these jobs:
1. rename {check,update}_extent_cache to {lookup,update}_extent_info;
2. introduce universal lookup/update interface of extent cache:
f2fs_{lookup,update}_extent_cache including above two real functions, then
export them to function callers.

So after above cleanup, we can add new rb-tree based extent cache into exported
interfaces.

v2:
 o remove "f2fs_" for inner function {lookup,update}_extent_info suggested by
   Jaegeuk Kim.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch introduces f2fs_map_bh to clean codes of check_extent_cache.

v2:
 o cleanup f2fs_map_bh pointed out by Jaegeuk Kim.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Rename a filed name from 'blk_addr' to 'blk' in struct {f2fs_extent,extent_info}
as annotation of this field descripts its meaning well to us.

By this way, we can avoid long statement in code of following patches.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Move ext_lock out of struct extent_info, then in the following patches we can
use variables with struct extent_info type as a parameter to pass pure data.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

We should stat inline data information for temp file in f2fs_tmpfile if we
enable inline_data feature.

Otherwise, inline data stat number will be wrong after this temp file is
evicted.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch uses ->writepage of meta mapping in sync_meta_pages instead of
f2fs_write_meta_page, by this way, in its caller we can ignore any changes
(e.g. changing name) of this registered function.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch introduces f2fs_update_dentry to remove redundant code in
f2fs_add_inline_entry and __f2fs_add_link.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

inline_dentry_addr is introduced with inline dentry feature without being used,
now we do not need to keep it for any reason, so remove it.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This is a tricky story of the new atomic state handling and the legacy
code fighting over each another. The bug at hand is an underrun of the
framebuffer reference with subsequent hilarity caused by the load
detect code. Which is peculiar since the the exact same code works
fine as the implementation of the legacy setcrtc ioctl.

Let's look at the ingredients:

- Currently our code is a crazy mix of legacy modeset interfaces to
  set the parameters and half-baked atomic state tracking underneath.
  While this transition is going we're using the transitional plane
  helpers to update the atomic side (drm_plane_helper_disable/update
  and friends), i.e. plane->state->fb. Since the state structure owns
  the fb those functions take care of that themselves.

  The legacy state (specifically crtc->primary->fb) is still managed
  by the old code (and mostly by the drm core), with the fb reference
  counting done by callers (core drm for the ioctl or the i915 load
  detect code). The relevant commit is

  commit ea2c67bb
  Author: Matt Roper <matthew.d.roper@intel.com>
  Date:   Tue Dec 23 10:41:52 2014 -0800

      drm/i915: Move to atomic plane helpers (v9)

- drm_plane_helper_disable has special code to handle multiple calls
  in a row - it checks plane->crtc == NULL and bails out. This is to
  match the proper atomic implementation which needs the crtc to get
  at the implied locking context atomic updates always need. See

  commit acf24a39
  Author: Daniel Vetter <daniel.vetter@ffwll.ch>
  Date:   Tue Jul 29 15:33:05 2014 +0200

      drm/plane-helper: transitional atomic plane helpers

- The universal plane code split out the implicit primary plane from
  the CRTC into it's own full-blown drm_plane object. As part of that
  the setcrtc ioctl (which updated both the crtc mode and primary
  plane) learned to set crtc->primary->crtc on modeset to make sure
  the plane->crtc assignments statate up to date in

  commit e13161af
  Author: Matt Roper <matthew.d.roper@intel.com>
  Date:   Tue Apr 1 15:22:38 2014 -0700

      drm: Add drm_crtc_init_with_planes() (v2)

  Unfortunately we've forgotten to update the load detect code. Which
  wasn't a problem since the load detect modeset is temporary and
  always undone before we drop the locks.

- Finally there is a organically grown history (i.e. don't ask) around
  who sets the legacy plane->fb for the various driver entry points.
  Originally updating that was the drivers duty, but for almost all
  places we've moved that (plus updating the refcounts) into the core.
  Again the exception is the load detect code.

Taking all together the following happens:
- The load detect code doesn't set crtc->primary->crtc. This is only
  really an issue on crtcs never before used or when userspace
  explicitly disabled the primary plane.

- The plane helper glue code short-circuits because of that and leaves
  a non-NULL fb behind in plane->state->fb and plane->fb. The state
  fb isn't a real problem (it's properly refcounted on its own), it's
  just the canary.

- Load detect code drops the reference for that fb, but doesn't set
  plane->fb = NULL. This is ok since it's still living in that old
  world where drivers had to clear the pointer but the core/callers
  handled the refcounting.

- On the next modeset the drm core notices plane->fb and takes care of
  refcounting it properly by doing another unref. This drops the
  refcount to zero, leaving state->plane now pointing at freed memory.

- intel_plane_duplicate_state still assume it owns a reference to that
  very state->fb and bad things start to happen.

Fix this all by applying the same duct-tape as for the legacy setcrtc
ioctl code and set crtc->primary->crtc properly.

Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Paul Bolle <pebolle@tiscali.nl>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Paulo Zanoni <przanoni@gmail.com>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: Matt Roper <matthew.d.roper@intel.com>
Reported-and-tested-by: NLinus Torvalds <torvalds@linux-foundation.org>
Reported-by: NPaul Bolle <pebolle@tiscali.nl>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Pull GPIO fixes from Linus Walleij:
 "Two GPIO fixes:

   - Fix a translation problem in of_get_named_gpiod_flags()

   - Fix a long standing container_of() mistake in the TPS65912 driver"

* tag 'gpio-v4.0-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
  gpio: tps65912: fix wrong container_of arguments
  gpiolib: of: allow of_gpiochip_find_and_xlate to find more than one chip per node

Merge branch 'fixes-for-4.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal

Pull thermal management fixes from Eduardo Valentin:
 "Specifics:

   - Several fixes in tmon tool.

   - Fixes in intel int340x for _ART and _TRT tables.

   - Add id for Avoton SoC into powerclamp driver.

   - Fixes in RCAR thermal driver to remove race conditions and fix fail
     path

   - Fixes in TI thermal driver: removal of unnecessary code and build
     fix if !CONFIG_PM_SLEEP

   - Cleanups in exynos thermal driver

   - Add stubs for include/linux/thermal.h.  Now drivers using thermal
     calls but that also work without CONFIG_THERMAL will be able to
     compile for systems that don't care about thermal.

  Note: I am sending this pull on Rui's behalf while he fixes issues in
  his Linux box"

* 'fixes-for-4.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal:
  thermal: int340x_thermal: Ignore missing _ART, _TRT tables
  thermal/intel_powerclamp: add id for Avoton SoC
  tools/thermal: tmon: silence 'set but not used' warnings
  tools/thermal: tmon: use pkg-config to determine library dependencies
  tools/thermal: tmon: support cross-compiling
  tools/thermal: tmon: add .gitignore
  tools/thermal: tmon: fixup tui windowing calculations
  tools/thermal: tmon: tui: don't hard-code dialog window size assumptions
  tools/thermal: tmon: add min/max macros
  tools/thermal: tmon: add --target-temp parameter
  thermal: exynos: Clean-up code to use oneline entry for exynos compatible table
  thermal: rcar: Make error and remove paths symmetrical with init
  thermal: rcar: Fix race condition between init and interrupt
  thermal: Introduce dummy functions when thermal is not defined
  ti-soc-thermal: Delete an unnecessary check before the function call "cpufreq_cooling_unregister"
  thermal: ti-soc-thermal: bandgap: Fix build warning if !CONFIG_PM_SLEEP

Pull md fixes from Neil Brown:
 "Three md fixes:

   - fix a read-balance problem that was reported 2 years ago, but that
     I never noticed the report :-(

   - fix for rare RAID6 problem causing incorrect bitmap updates when
     two devices fail.

   - add __ATTR_PREALLOC annotation now that it is possible"

* tag 'md/4.0-fixes' of git://neil.brown.name/md:
  md: mark some attributes as pre-alloc
  raid5: check faulty flag for array status during recovery.
  md/raid1: fix read balance when a drive is write-mostly.

Pull arch/metag fix from James Hogan:
 "This is just a single patch to fix the KSTK_EIP() and KSTK_ESP()
  macros for metag which have always been erronously returning the PC
  and stack pointer of the task's kernel context rather than from its
  user context saved at entry from userland into the kernel, which
  affects the contents of /proc/<pid>/maps and /proc/<pid>/stat"

* tag 'metag-fixes-v4.0-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag:
  metag: Fix KSTK_EIP() and KSTK_ESP() macros

Pull x86 fixes from Ingo Molnar:
 "A CR4-shadow 32-bit init fix, plus two typo fixes"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Init per-cpu shadow copy of CR4 on 32-bit CPUs too
  x86/platform/intel-mid: Fix trivial printk message typo in intel_mid_arch_setup()
  x86/cpu/intel: Fix trivial typo in intel_tlb_table[]

Pull timer fixes from Ingo Molnar:
 "Three clockevents/clocksource driver fixes"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource: pxa: Fix section mismatch
  clocksource: mtk: Fix race conditions in probe code
  clockevents: asm9260: Fix compilation error with sparc/sparc64 allyesconfig

Pull perf fixes from Ingo Molnar:
 "Two kprobes fixes and a handful of tooling fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf tools: Make sparc64 arch point to sparc
  perf symbols: Define EM_AARCH64 for older OSes
  perf top: Fix SIGBUS on sparc64
  perf tools: Fix probing for PERF_FLAG_FD_CLOEXEC flag
  perf tools: Fix pthread_attr_setaffinity_np build error
  perf tools: Define _GNU_SOURCE on pthread_attr_setaffinity_np feature check
  perf bench: Fix order of arguments to memcpy_alloc_mem
  kprobes/x86: Check for invalid ftrace location in __recover_probed_insn()
  kprobes/x86: Use 5-byte NOP when the code might be modified by ftrace

Pull locking fix from Ingo Molnar:
 "An rtmutex deadlock path fixlet"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/rtmutex: Set state back to running on error

Merge tag 'perf-urgent-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent

Pull perf/urgent fixes from Arnaldo Carvalho de Melo:

  - pthread_attr_setaffinity_np() feature detection build fixes (Adrian Hunter, Josh Boyer)

  - Fix probing for PERF_FLAG_FD_CLOEXEC flag (Adrian Hunter)

  - Fix order of arguments to memcpy_alloc_mem in 'perf bench' (Bruce Merry)

  - Sparc64 and Aarch64 build and segfault fixes (David Ahern)
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NIngo Molnar <mingo@kernel.org>

The "usual" path is:

 - rt_mutex_slowlock()
 - set_current_state()
 - task_blocks_on_rt_mutex() (ret 0)
 - __rt_mutex_slowlock()
   - sleep or not but do return with __set_current_state(TASK_RUNNING)
 - back to caller.

In the early error case where task_blocks_on_rt_mutex() return
-EDEADLK we never change the task's state back to RUNNING. I
assume this is intended. Without this change after ww_mutex
using rt_mutex the selftest passes but later I get plenty of:

  | bad: scheduling from the idle thread!

backtraces.
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: NMike Galbraith <umgwanakikbuti@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: afffc6c1 ("locking/rtmutex: Optimize setting task running after being blocked")
Link: http://lkml.kernel.org/r/1425056229-22326-4-git-send-email-bigeasy@linutronix.deSigned-off-by: NIngo Molnar <mingo@kernel.org>

Pull drm fixes from Dave Airlie:
 "Just general fixes: radeon, i915, atmel, tegra, amdkfd and one core
  fix"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (28 commits)
  drm: atmel-hlcdc: remove clock polarity from crtc driver
  drm/radeon: only enable DP audio if the monitor supports it
  drm/radeon: fix atom aux payload size check for writes (v2)
  drm/radeon: fix 1 RB harvest config setup for TN/RL
  drm/radeon: enable SRBM timeout interrupt on EG/NI
  drm/radeon: enable SRBM timeout interrupt on SI
  drm/radeon: enable SRBM timeout interrupt on CIK v2
  drm/radeon: dump full IB if we hit a packet error
  drm/radeon: disable mclk switching with 120hz+ monitors
  drm/radeon: use drm_mode_vrefresh() rather than mode->vrefresh
  drm/radeon: enable native backlight control on old macs
  drm/i915: Fix frontbuffer false positve.
  drm/i915: Align initial plane backing objects correctly
  drm/i915: avoid processing spurious/shared interrupts in low-power states
  drm/i915: Check obj->vma_list under the struct_mutex
  drm/i915: Fix a use after free, and unbalanced refcounting
  drm: atmel-hlcdc: remove useless pm_runtime_put_sync in probe
  drm: atmel-hlcdc: reset layer A2Q and UPDATE bits when disabling it
  drm: Fix deadlock due to getconnector locking changes
  drm/i915: Dell Chromebook 11 has PWM backlight
  ...

Pull block layer fixes from Jens Axboe:
 "Two smaller fixes for this cycle:

   - A fixup from Keith so that NVMe compiles without BLK_INTEGRITY,
     basically just moving the code around appropriately.

   - A fixup for shm, fixing an oops in shmem_mapping() for mapping with
     no inode.  From Sasha"

[ The shmem fix doesn't look block-layer-related, but fixes a bug that
  happened due to the backing_dev_info removal..  - Linus ]

* 'for-linus' of git://git.kernel.dk/linux-block:
  mm: shmem: check for mapping owner before dereferencing
  NVMe: Fix for BLK_DEV_INTEGRITY not set

Pull xfs fixes from Dave Chinner:
 "These are fixes for regressions/bugs introduced in the 4.0 merge cycle
  and problems discovered during the merge window that need to be pushed
  back to stable kernels ASAP.

  This contains:
   - ensure quota type is reset in on-disk dquots
   - fix missing partial EOF block data flush on truncate extension
   - fix transaction leak in error handling for new pnfs block layout
     support
   - add missing target_ip check to RENAME_EXCHANGE"

* tag 'xfs-for-linus-4.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs:
  xfs: cancel failed transaction in xfs_fs_commit_blocks()
  xfs: Ensure we have target_ip for RENAME_EXCHANGE
  xfs: ensure truncate forces zeroed blocks to disk
  xfs: Fix quota type in quota structures when reusing quota file

Merge misc fixes from Andrew Morton:
 "13 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm: add missing __PAGETABLE_{PUD,PMD}_FOLDED defines
  mm: page_alloc: revert inadvertent !__GFP_FS retry behavior change
  kernel/sys.c: fix UNAME26 for 4.0
  mm: memcontrol: use "max" instead of "infinity" in control knobs
  zram: use proper type to update max_used_pages
  drivers/rtc/rtc-ds1685.c: fix conditional in ds1685_rtc_sysfs_time_regs_{show,store}
  nilfs2: fix potential memory overrun on inode
  scripts/gdb: add empty package initialization script
  rtc: ds1685: remove superfluous checks for out-of-range u8 values
  rtc: ds1685: fix ds1685_rtc_alarm_irq_enable build error
  memcg: fix low limit calculation
  mm/nommu: fix memory leak
  ocfs2: update web page + git tree in documentation

Core mm expects __PAGETABLE_{PUD,PMD}_FOLDED to be defined if these page
table levels folded.  Usually, these defines are provided by
<asm-generic/pgtable-nopmd.h> and <asm-generic/pgtable-nopud.h>.

But some architectures fold page table levels in a custom way.  They
need to define these macros themself.  This patch adds missing defines.

The patch fixes mm->nr_pmds underflow and eliminates dead __pmd_alloc()
and __pud_alloc() on architectures without these page table levels.
Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: David Howells <dhowells@redhat.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Historically, !__GFP_FS allocations were not allowed to invoke the OOM
killer once reclaim had failed, but nevertheless kept looping in the
allocator.

Commit 9879de73 ("mm: page_alloc: embed OOM killing naturally into
allocation slowpath"), which should have been a simple cleanup patch,
accidentally changed the behavior to aborting the allocation at that
point.  This creates problems with filesystem callers (?) that currently
rely on the allocator waiting for other tasks to intervene.

Revert the behavior as it shouldn't have been changed as part of a
cleanup patch.

Fixes: 9879de73 ("mm: page_alloc: embed OOM killing naturally into allocation slowpath")
Signed-off-by: NJohannes Weiner <hannes@cmpxchg.org>
Acked-by: NMichal Hocko <mhocko@suse.cz>
Reported-by: NTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Dave Chinner <david@fromorbit.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: <stable@vger.kernel.org>	[3.19.x]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There's a uname workaround for broken userspace which can't handle kernel
versions of 3.x.  Update it for 4.x.
Signed-off-by: NJon DeVree <nuxi@vault24.org>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>