get_user_pages(write=1, force=1) has always had odd behaviour on write-
protected shared mappings: although it demands FMODE_WRITE-access to the
underlying object (do_mmap_pgoff sets neither VM_SHARED nor VM_MAYWRITE
without that), it ends up with do_wp_page substituting private anonymous
Copied-On-Write pages for the shared file pages in the area.

That was long ago intentional, as a safety measure to prevent ptrace
setting a breakpoint (or POKETEXT or POKEDATA) from inadvertently
corrupting the underlying executable.  Yet exec and dynamic loaders open
the file read-only, and use MAP_PRIVATE rather than MAP_SHARED.

The traditional odd behaviour still causes surprises and bugs in mm, and
is probably not what any caller wants - even the comment on the flag
says "You do not want this" (although it's undoubtedly necessary for
overriding userspace protections in some contexts, and good when !write).

Let's stop doing that.  But it would be dangerous to remove the long-
standing safety at this stage, so just make get_user_pages(write,force)
fail with EFAULT when applied to a write-protected shared area.
Infiniband may in future want to force write through to underlying
object: we can add another FOLL_flag later to enable that if required.

Odd though the old behaviour was, there is no doubt that we may turn out
to break userspace with this change, and have to revert it quickly.
Issue a WARN_ON_ONCE to help debug the changed case (easily triggered by
userspace, so only once to prevent spamming the logs); and delay a few
associated cleanups until this change is proved.

get_user_pages callers who might see trouble from this change:
  ptrace poking, or writing to /proc/<pid>/mem
  drivers/infiniband/
  drivers/media/v4l2-core/
  drivers/gpu/drm/exynos/exynos_drm_gem.c
  drivers/staging/tidspbridge/core/tiomap3430.c
if they ever apply get_user_pages to write-protected shared mappings
of an object which was opened for writing.

I went to apply the same change to mm/nommu.c, but retreated.  NOMMU has
no place for COW, and its VM_flags conventions are not the same: I'd be
more likely to screw up NOMMU than make an improvement there.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull xfs update from Dave Chinner:
 "There are a couple of new fallocate features in this request - it was
  decided that it was easiest to push them through the XFS tree using
  topic branches and have the ext4 support be based on those branches.
  Hence you may see some overlap with the ext4 tree merge depending on
  how they including those topic branches into their tree.  Other than
  that, there is O_TMPFILE support, some cleanups and bug fixes.

  The main changes in the XFS tree for 3.15-rc1 are:

   - O_TMPFILE support
   - allowing AIO+DIO writes beyond EOF
   - FALLOC_FL_COLLAPSE_RANGE support for fallocate syscall and XFS
     implementation
   - FALLOC_FL_ZERO_RANGE support for fallocate syscall and XFS
     implementation
   - IO verifier cleanup and rework
   - stack usage reduction changes
   - vm_map_ram NOIO context fixes to remove lockdep warings
   - various bug fixes and cleanups"

* tag 'xfs-for-linus-3.15-rc1' of git://oss.sgi.com/xfs/xfs: (34 commits)
  xfs: fix directory hash ordering bug
  xfs: extra semi-colon breaks a condition
  xfs: Add support for FALLOC_FL_ZERO_RANGE
  fs: Introduce FALLOC_FL_ZERO_RANGE flag for fallocate
  xfs: inode log reservations are still too small
  xfs: xfs_check_page_type buffer checks need help
  xfs: avoid AGI/AGF deadlock scenario for inode chunk allocation
  xfs: use NOIO contexts for vm_map_ram
  xfs: don't leak EFSBADCRC to userspace
  xfs: fix directory inode iolock lockdep false positive
  xfs: allocate xfs_da_args to reduce stack footprint
  xfs: always do log forces via the workqueue
  xfs: modify verifiers to differentiate CRC from other errors
  xfs: print useful caller information in xfs_error_report
  xfs: add xfs_verifier_error()
  xfs: add helper for updating checksums on xfs_bufs
  xfs: add helper for verifying checksums on xfs_bufs
  xfs: Use defines for CRC offsets in all cases
  xfs: skip pointless CRC updates after verifier failures
  xfs: Add support FALLOC_FL_COLLAPSE_RANGE for fallocate
  ...

Pull ext4 updates from Ted Ts'o:
 "Major changes for 3.14 include support for the newly added ZERO_RANGE
  and COLLAPSE_RANGE fallocate operations, and scalability improvements
  in the jbd2 layer and in xattr handling when the extended attributes
  spill over into an external block.

  Other than that, the usual clean ups and minor bug fixes"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (42 commits)
  ext4: fix premature freeing of partial clusters split across leaf blocks
  ext4: remove unneeded test of ret variable
  ext4: fix comment typo
  ext4: make ext4_block_zero_page_range static
  ext4: atomically set inode->i_flags in ext4_set_inode_flags()
  ext4: optimize Hurd tests when reading/writing inodes
  ext4: kill i_version support for Hurd-castrated file systems
  ext4: each filesystem creates and uses its own mb_cache
  fs/mbcache.c: doucple the locking of local from global data
  fs/mbcache.c: change block and index hash chain to hlist_bl_node
  ext4: Introduce FALLOC_FL_ZERO_RANGE flag for fallocate
  ext4: refactor ext4_fallocate code
  ext4: Update inode i_size after the preallocation
  ext4: fix partial cluster handling for bigalloc file systems
  ext4: delete path dealloc code in ext4_ext_handle_uninitialized_extents
  ext4: only call sync_filesystm() when remounting read-only
  fs: push sync_filesystem() down to the file system's remount_fs()
  jbd2: improve error messages for inconsistent journal heads
  jbd2: minimize region locked by j_list_lock in jbd2_journal_forget()
  jbd2: minimize region locked by j_list_lock in journal_get_create_access()
  ...

Pull pstore fixes from Tony Luck:
 "Series of small bug fixes for pstore"

* tag 'please-pull-pstore' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux:
  pstore: Fix memory leak when decompress using big_oops_buf
  pstore: Fix buffer overflow while write offset equal to buffer size
  pstore: Correct the max_dump_cnt clearing of ramoops
  pstore: Fix NULL pointer fault if get NULL prz in ramoops_get_next_prz
  pstore: skip zero size persistent ram buffer in traverse
  pstore: clarify clearing of _read_cnt in ramoops_context

Pull ubifs updates from Artem Bityutskiy:
 "This pull request includes the 'ubiblock' driver which provides R/O
  block access to UBI volumes.  It is useful for those who want to use
  squashfs on top of raw flash devices.  UBI will provide bit-flip
  handling and wear-levelling in this case (e.g., if there are other UBI
  volumes with R/W UBIFS too).

  The driver is actually pretty small and it is part of the UBI kernel
  subsystem.  Delivered by Ezequiel Garcia, along with a piece of
  documentation on the MTD web site and the user-space tool for creating
  and removing block devices"

* tag 'upstream-3.15-rc1' of git://git.infradead.org/linux-ubifs:
  UBI: block: Remove __initdata from ubiblock_param_ops
  UBI: make UBI_IOCVOLCRBLK take a parameter for future usage
  UBI: rename block device ioctls
  UBI: block: Use ENOSYS as return value when CONFIG_UBIBLOCK=n
  UBI: block: Add CONFIG_BLOCK dependency
  UBI: block: Use 'u64' for the 64-bit dividend
  UBI: block: Mark init-only symbol as __initdata
  UBI: block: do not use term "attach"
  UBI: R/O block driver on top of UBI volumes

Pull fuse update from Miklos Szeredi:
 "This series adds cached writeback support to fuse, improving write
  throughput"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: fix "uninitialized variable" warning
  fuse: Turn writeback cache on
  fuse: Fix O_DIRECT operations vs cached writeback misorder
  fuse: fuse_flush() should wait on writeback
  fuse: Implement write_begin/write_end callbacks
  fuse: restructure fuse_readpage()
  fuse: Flush files on wb close
  fuse: Trust kernel i_mtime only
  fuse: Trust kernel i_size only
  fuse: Connection bit for enabling writeback
  fuse: Prepare to handle short reads
  fuse: Linking file to inode helper

Pull dlm updates from David Teigland:
 "This set includes a couple trivial cleanups and changes recovery log
  messages from DEBUG to INFO"

* tag 'dlm-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm:
  dlm: use INFO for recovery messages
  fs: Include appropriate header file in dlm/ast.c
  dlm: silence a harmless use after free warning

Pull btrfs changes from Chris Mason:
 "This is a pretty long stream of bug fixes and performance fixes.

  Qu Wenruo has replaced the btrfs async threads with regular kernel
  workqueues.  We'll keep an eye out for performance differences, but
  it's nice to be using more generic code for this.

  We still have some corruption fixes and other patches coming in for
  the merge window, but this batch is tested and ready to go"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (108 commits)
  Btrfs: fix a crash of clone with inline extents's split
  btrfs: fix uninit variable warning
  Btrfs: take into account total references when doing backref lookup
  Btrfs: part 2, fix incremental send's decision to delay a dir move/rename
  Btrfs: fix incremental send's decision to delay a dir move/rename
  Btrfs: remove unnecessary inode generation lookup in send
  Btrfs: fix race when updating existing ref head
  btrfs: Add trace for btrfs_workqueue alloc/destroy
  Btrfs: less fs tree lock contention when using autodefrag
  Btrfs: return EPERM when deleting a default subvolume
  Btrfs: add missing kfree in btrfs_destroy_workqueue
  Btrfs: cache extent states in defrag code path
  Btrfs: fix deadlock with nested trans handles
  Btrfs: fix possible empty list access when flushing the delalloc inodes
  Btrfs: split the global ordered extents mutex
  Btrfs: don't flush all delalloc inodes when we doesn't get s_umount lock
  Btrfs: reclaim delalloc metadata more aggressively
  Btrfs: remove unnecessary lock in may_commit_transaction()
  Btrfs: remove the unnecessary flush when preparing the pages
  Btrfs: just do dirty page flush for the inode with compression before direct IO
  ...

Pull GFS2 updates from Steven Whitehouse:
 "One of the main highlights this time, is not the patches themselves
  but instead the widening contributor base.  It is good to see that
  interest is increasing in GFS2, and I'd like to thank all the
  contributors to this patch set.

  In addition to the usual set of bug fixes and clean ups, there are
  patches to improve inode creation performance when xattrs are required
  and some improvements to the transaction code which is intended to
  help improve scalability after further changes in due course.

  Journal extent mapping is also updated to make it more efficient and
  again, this is a foundation for future work in this area.

  The maximum number of ACLs has been increased to 300 (for a 4k block
  size) which means that even with a few additional xattrs from selinux,
  everything should fit within a single fs block.

  There is also a patch to bring GFS2's own copy of the writepages code
  up to the same level as the core VFS.  Eventually we may be able to
  merge some of this code, since it is fairly similar.

  The other major change this time, is bringing consistency to the
  printing of messages via fs_<level>, pr_<level> macros"

* tag 'gfs2-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-nmw: (29 commits)
  GFS2: Fix address space from page function
  GFS2: Fix uninitialized VFS inode in gfs2_create_inode
  GFS2: Fix return value in slot_get()
  GFS2: inline function gfs2_set_mode
  GFS2: Remove extraneous function gfs2_security_init
  GFS2: Increase the max number of ACLs
  GFS2: Re-add a call to log_flush_wait when flushing the journal
  GFS2: Ensure workqueue is scheduled after noexp request
  GFS2: check NULL return value in gfs2_ok_to_move
  GFS2: Convert gfs2_lm_withdraw to use fs_err
  GFS2: Use fs_<level> more often
  GFS2: Use pr_<level> more consistently
  GFS2: Move recovery variables to journal structure in memory
  GFS2: global conversion to pr_foo()
  GFS2: return -E2BIG if hit the maximum limits of ACLs
  GFS2: Clean up journal extent mapping
  GFS2: replace kmalloc - __vmalloc / memset 0
  GFS2: Remove extra "if" in gfs2_log_flush()
  fs: NULL dereference in posix_acl_to_xattr()
  GFS2: Move log buffer accounting to transaction
  ...

Pull file locking updates from Jeff Layton:
 "Highlights:

   - maintainership change for fs/locks.c.  Willy's not interested in
     maintaining it these days, and is OK with Bruce and I taking it.
   - fix for open vs setlease race that Al ID'ed
   - cleanup and consolidation of file locking code
   - eliminate unneeded BUG() call
   - merge of file-private lock implementation"

* 'locks-3.15' of git://git.samba.org/jlayton/linux:
  locks: make locks_mandatory_area check for file-private locks
  locks: fix locks_mandatory_locked to respect file-private locks
  locks: require that flock->l_pid be set to 0 for file-private locks
  locks: add new fcntl cmd values for handling file private locks
  locks: skip deadlock detection on FL_FILE_PVT locks
  locks: pass the cmd value to fcntl_getlk/getlk64
  locks: report l_pid as -1 for FL_FILE_PVT locks
  locks: make /proc/locks show IS_FILE_PVT locks as type "FLPVT"
  locks: rename locks_remove_flock to locks_remove_file
  locks: consolidate checks for compatible filp->f_mode values in setlk handlers
  locks: fix posix lock range overflow handling
  locks: eliminate BUG() call when there's an unexpected lock on file close
  locks: add __acquires and __releases annotations to locks_start and locks_stop
  locks: remove "inline" qualifier from fl_link manipulation functions
  locks: clean up comment typo
  locks: close potential race between setlease and open
  MAINTAINERS: update entry for fs/locks.c

Pull renameat2 system call from Miklos Szeredi:
 "This adds a new syscall, renameat2(), which is the same as renameat()
  but with a flags argument.

  The purpose of extending rename is to add cross-rename, a symmetric
  variant of rename, which exchanges the two files.  This allows
  interesting things, which were not possible before, for example
  atomically replacing a directory tree with a symlink, etc...  This
  also allows overlayfs and friends to operate on whiteouts atomically.

  Andy Lutomirski also suggested a "noreplace" flag, which disables the
  overwriting behavior of rename.

  These two flags, RENAME_EXCHANGE and RENAME_NOREPLACE are only
  implemented for ext4 as an example and for testing"

* 'cross-rename' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  ext4: add cross rename support
  ext4: rename: split out helper functions
  ext4: rename: move EMLINK check up
  ext4: rename: create ext4_renament structure for local vars
  vfs: add cross-rename
  vfs: lock_two_nondirectories: allow directory args
  security: add flags to rename hooks
  vfs: add RENAME_NOREPLACE flag
  vfs: add renameat2 syscall
  vfs: rename: use common code for dir and non-dir
  vfs: rename: move d_move() up
  vfs: add d_is_dir()

Pull media updates from Mauro Carvalho Chehab:
 "The main set of series of patches for media subsystem, including:
   - document RC sysfs class
   - added an API to setup scancode to allow waking up systems using the
     Remote Controller
   - add API for SDR devices.  Drivers are still on staging
   - some API improvements for getting EDID data from media
     inputs/outputs
   - new DVB frontend driver for drx-j (ATSC)
   - one driver (it913x/it9137) got removed, in favor of an improvement
     on another driver (af9035)
   - added a skeleton V4L2 PCI driver at documentation
   - added a dual flash driver (lm3646)
   - added a new IR driver (img-ir)
   - added an IR scancode decoder for the Sharp protocol
   - some improvements at the usbtv driver, to allow its core to be
     reused.
   - added a new SDR driver (rtl2832u_sdr)
   - added a new tuner driver (msi001)
   - several improvements at em28xx driver to fix PM support, device
     removal and to split the V4L2 specific bits into a separate
     sub-driver
   - one driver got converted to videobuf2 (s2255drv)
   - the e4000 tuner driver now follows an improved binding model
   - some fixes at V4L2 compat32 code
   - several fixes and enhancements at videobuf2 code
   - some cleanups at V4L2 API documentation
   - usual driver enhancements, new board additions and misc fixups"

[ NOTE! This merge effective drops commit 4329b93b ("of: Reduce
  indentation in of_graph_get_next_endpoint").

  The of_graph_get_next_endpoint() function was moved and renamed by
  commit fd9fdb78 ("[media] of: move graph helpers from
  drivers/media/v4l2-core to drivers/of").  It was originally called
  v4l2_of_get_next_endpoint() and lived in the file
  drivers/media/v4l2-core/v4l2-of.c.

  In that original location, it was then fixed to support empty port
  nodes by commit b9db140c ("[media] v4l: of: Support empty port
  nodes"), and that commit clashes badly with the dropped "Reduce
  intendation" commit.  I had to choose one or the other, and decided
  that the "Support empty port nodes" commit was more important ]

* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (426 commits)
  [media] em28xx-dvb: fix PCTV 461e tuner I2C binding
  Revert "[media] em28xx-dvb: fix PCTV 461e tuner I2C binding"
  [media] em28xx: fix PCTV 290e LNA oops
  [media] em28xx-dvb: fix PCTV 461e tuner I2C binding
  [media] m88ds3103: fix bug on .set_tone()
  [media] saa7134: fix WARN_ON during resume
  [media] v4l2-dv-timings: add module name, description, license
  [media] videodev2.h: add parenthesis around macro arguments
  [media] saa6752hs: depends on CRC32
  [media] si4713: fix Kconfig dependencies
  [media] Sensoray 2255 uses videobuf2
  [media] adv7180: free an interrupt on failure paths in init_device()
  [media] e4000: make VIDEO_V4L2 dependency optional
  [media] af9033: Don't export functions for the hardware filter
  [media] af9035: use af9033 PID filters
  [media] af9033: implement PID filter
  [media] rtl2832_sdr: do not use dynamic stack allocation
  [media] e4000: fix 32-bit build error
  [media] em28xx-audio: make sure audio is unmuted on open()
  [media] DocBook media: v4l2_format_sdr was renamed to v4l2_sdr_format
  ...

Pull sb_edac patches from Mauro Carvalho Chehab:
 "A couple sb_edac driver improvements, cleaning a little bit the amount
  of data sent to dmesg, and fixing one error message"

* 'linux_next' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-edac:
  sb_edac: mark MCE messages as KERN_DEBUG
  sb_edac: use "event" instead of "exception" when MC wasnt signaled

Pull input updates from Dmitry Torokhov:
 "The first round of updates for the input subsystem.

  Just new drivers and existing driver fixes, no core changes except for
  the new uinput IOCTL to allow userspace to fetch sysfs name of the
  input device that was created"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (43 commits)
  Input: edt-ft5x06 - add a missing condition
  Input: appletouch - fix jumps when additional fingers are detected
  Input: appletouch - implement sensor data smoothing
  Input: add driver for SOC button array
  Input: pm8xxx-vibrator - add DT match table
  Input: pmic8xxx-pwrkey - migrate to DT
  Input: pmic8xxx-keypad - migrate to DT
  Input: pmic8xxx-keypad - migrate to regmap APIs
  Input: pmic8xxx-keypad - migrate to devm_* APIs
  Input: pmic8xxx-keypad - fix build by removing gpio configuration
  Input: add new driver for ARM CLPS711X keypad
  Input: edt-ft5x06 - add support for M09 firmware version
  Input: edt-ft5x06 - ignore touchdown events
  Input: edt-ft5x06 - adjust delays to conform datasheet
  Input: edt-ft5x06 - add DT support
  Input: edt-ft5x06 - several cleanups; no functional change
  Input: appletouch - dial back fuzz setting
  Input: remove obsolete tnetv107x drivers
  Input: sirfsoc-onkey - set the capability of reporting KEY_POWER
  Input: da9052_onkey - use correct register bit for key status
  ...

Pull infiniband updates from Roland Dreier:
 "Main batch of InfiniBand/RDMA changes for 3.15:

   - The biggest change is core API extensions and mlx5 low-level driver
     support for handling DIF/DIX-style protection information, and the
     addition of PI support to the iSER initiator.  Target support will
     be arriving shortly through the SCSI target tree.

   - A nice simplification to the "umem" memory pinning library now that
     we have chained sg lists.  Kudos to Yishai Hadas for realizing our
     code didn't have to be so crazy.

   - Another nice simplification to the sg wrappers used by qib, ipath
     and ehca to handle their mapping of memory to adapter.

   - The usual batch of fixes to bugs found by static checkers etc.
     from intrepid people like Dan Carpenter and Yann Droneaud.

   - A large batch of cxgb4, ocrdma, qib driver updates"

* tag 'rdma-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband: (102 commits)
  RDMA/ocrdma: Unregister inet notifier when unloading ocrdma
  RDMA/ocrdma: Fix warnings about pointer <-> integer casts
  RDMA/ocrdma: Code clean-up
  RDMA/ocrdma: Display FW version
  RDMA/ocrdma: Query controller information
  RDMA/ocrdma: Support non-embedded mailbox commands
  RDMA/ocrdma: Handle CQ overrun error
  RDMA/ocrdma: Display proper value for max_mw
  RDMA/ocrdma: Use non-zero tag in SRQ posting
  RDMA/ocrdma: Memory leak fix in ocrdma_dereg_mr()
  RDMA/ocrdma: Increment abi version count
  RDMA/ocrdma: Update version string
  be2net: Add abi version between be2net and ocrdma
  RDMA/ocrdma: ABI versioning between ocrdma and be2net
  RDMA/ocrdma: Allow DPP QP creation
  RDMA/ocrdma: Read ASIC_ID register to select asic_gen
  RDMA/ocrdma: SQ and RQ doorbell offset clean up
  RDMA/ocrdma: EQ full catastrophe avoidance
  RDMA/cxgb4: Disable DSGL use by default
  RDMA/cxgb4: rx_data() needs to hold the ep mutex
  ...

Pull second round of hwmon updates from Guenter Roeck:
 "Add support for AMD F16 M30h processor to k10temp driver.

  This adds one more patch which had secondary dependencies.  The branch
  point is arbitrary, but I did run a full set of build and qemu tests
  on it.  While there are some new build failures (6 out of 122 in my
  builds), none are due to this commit"

* tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (k10temp) Add support for AMD F16 M30h processor

Pull bulk of gpio updates from Linus Walleij:
 "A pretty big chunk of changes this time, but it has all been on
  rotation in linux-next and had some testing.  Of course there will be
  some amount of fixes on top...

   - Merged in a branch of irqchip changes from Thomas Gleixner: we need
     to have new callbacks from the irqchip to determine if the GPIO
     line will be eligible for IRQs, and this callback must be able to
     say "no".  After some thinking I got the branch from tglx and have
     switched all current users over to use this.

   - Based on tglx patches, we have added some generic irqchip helpers
     in the gpiolib core.  These will help centralize code when GPIO
     drivers have simple chained/cascaded IRQs.  Drivers will still
     define their irqchip vtables, but the gpiolib core will take care
     of irqdomain set-up, mapping from local offsets to Linux irqs, and
     reserve resources by marking the GPIO lines for IRQs.

   - Initially the PL061 and Nomadik GPIO/pin control drivers have been
     switched over to use the new gpiochip-to-irqchip infrastructure
     with more drivers expected for the next kernel cycle.  The
     factoring of just two drivers still makes it worth it so it is
     already a win.

   - A new driver for the Synopsys DesignWare APB GPIO block.

   - Modify the DaVinci GPIO driver to be reusable also for the new TI
     Keystone architecture.

   - A new driver for the LSI ZEVIO SoCs.

   - Delete the obsolte tnetv107x driver.

   - Some incremental work on GPIO descriptors: have
     gpiod_direction_output() use a logical level, respecting assertion
     polarity through ACTIVE_LOW flags, adding gpiod_direction_output_raw()
     for the case where you want to set that very value.  Add
     gpiochip_get_desc() to fetch a GPIO descriptor from a specific
     offset on a certain chip inside driver code.

   - Switch ACPI GPIO code over to using gpiochip_get_desc() and get rid
     of gpio_to_desc().

   - The ACPI GPIO event handling code has been reworked after
     encountering an actual real life implementation.

   - Support for ACPI GPIO operation regions.

   - Generic GPIO chips can now be assigned labels/names from platform
     data.

   - We now clamp values returned from GPIO drivers to the boolean [0,1]
     range.

   - Some improved documentation on how to use the polarity flag was
     added.

   - a large slew of incremental driver updates and non-critical fixes.
     Some targeted for stable"

* tag 'gpio-v3.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (80 commits)
  gpio: rcar: Add helper variable dev = &pdev->dev
  gpio-lynxpoint: force gpio_get() to return "1" and "0" only
  gpio: unmap gpio irqs properly
  pch_gpio: set value before enabling output direction
  gpio: moxart: Actually set output state in moxart_gpio_direction_output()
  gpio: moxart: Avoid forward declaration
  gpio: mxs: Allow for recursive enable_irq_wake() call
  gpio: samsung: Add missing "break" statement
  gpio: twl4030: Remove redundant assignment
  gpio: dwapb: correct gpio-cells in binding document
  gpio: iop: fix devm_ioremap_resource() return value checking
  pinctrl: coh901: convert driver to use gpiolib irqchip
  pinctrl: nomadik: convert driver to use gpiolib irqchip
  gpio: pl061: convert driver to use gpiolib irqchip
  gpio: add IRQ chip helpers in gpiolib
  pinctrl: nomadik: factor in platform data container
  pinctrl: nomadik: rename secondary to latent
  gpio: Driver for SYSCON-based GPIOs
  gpio: generic: Use platform_device_id->driver_data field for driver flags
  pinctrl: coh901: move irq line locking to resource callbacks
  ...

Merge first patch-bomb from Andrew Morton:
 - Various misc bits
 - kmemleak fixes
 - small befs, codafs, cifs, efs, freexxfs, hfsplus, minixfs, reiserfs things
 - fanotify
 - I appear to have become SuperH maintainer
 - ocfs2 updates
 - direct-io tweaks
 - a bit of the MM queue
 - printk updates
 - MAINTAINERS maintenance
 - some backlight things
 - lib/ updates
 - checkpatch updates
 - the rtc queue
 - nilfs2 updates
 - Small Documentation/ updates

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (237 commits)
  Documentation/SubmittingPatches: remove references to patch-scripts
  Documentation/SubmittingPatches: update some dead URLs
  Documentation/filesystems/ntfs.txt: remove changelog reference
  Documentation/kmemleak.txt: updates
  fs/reiserfs/super.c: add __init to init_inodecache
  fs/reiserfs: move prototype declaration to header file
  fs/hfsplus/attributes.c: add __init to hfsplus_create_attr_tree_cache()
  fs/hfsplus/extents.c: fix concurrent acess of alloc_blocks
  fs/hfsplus/extents.c: remove unused variable in hfsplus_get_block
  nilfs2: update project's web site in nilfs2.txt
  nilfs2: update MAINTAINERS file entries fix
  nilfs2: verify metadata sizes read from disk
  nilfs2: add FITRIM ioctl support for nilfs2
  nilfs2: add nilfs_sufile_trim_fs to trim clean segs
  nilfs2: implementation of NILFS_IOCTL_SET_SUINFO ioctl
  nilfs2: add nilfs_sufile_set_suinfo to update segment usage
  nilfs2: add struct nilfs_suinfo_update and flags
  nilfs2: update MAINTAINERS file entries
  fs/coda/inode.c: add __init to init_inodecache()
  BEFS: logging cleanup
  ...

The link to the tarball for Andrew Morton's patch scripts is dead.
These scripts don't seem to be used for kernel development these days
anyways so just rip out all references to them.
Signed-off-by: Mitchel Humpherys <mitchelh@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The links to "The perfect patch" and "NO!!!! No more huge patch
bombs..." have gone stale. Update them to some working locations.
Signed-off-by: Mitchel Humpherys <mitchelh@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

File was removed in commit 7c821a17 ("Remove fs/ntfs/ChangeLog").
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Acked-by: Anton Altaparmakov <anton@tuxera.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Update Documentatin/kmemleak.txt to reflect the following changes:

Commit b69ec42b ("Kconfig: clean up the long arch list for the
DEBUG_KMEMLEAK config option") made it so that we can't check supported
architectures by read Kconfig.debug.

Commit 85d3a316 ("kmemleak: use rbtree instead of prio tree")
converted kmemleak to use rbtree instead of prio tree.
Signed-off-by: Wang YanQing <udknight@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

init_inodecache is only called by __init init_reiserfs_fs.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Acked-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Move prototype declaration to header file reiserfs/reiserfs.h from
reiserfs/super.c because they are used by more than one file.

This eliminates the following warning in reiserfs/bitmap.c:

  fs/reiserfs/bitmap.c:647:6: warning: no previous prototype for `show_alloc_options' [-Wmissing-prototypes]
Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

hfsplus_create_attr_tree_cache is only called by __init init_hfsplus_fs
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Reviewed-by: Vyacheslav Dubeyko <slava@dubeyko.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Concurrent access to alloc_blocks in hfsplus_inode_info() is protected
by extents_lock mutex.  This patch fixes two instances where
alloc_blocks modification was not protected with this lock.

This fixes possible allocation bitmap corruption in race conditions
while extending and truncating files.

[akpm@linux-foundation.org: take extents_lock before taking a copy of ->alloc_blocks]
[akpm@linux-foundation.org: remove now-unused label `out']
Signed-off-by: Sougata Santra <sougata@tuxera.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Vyacheslav Dubeyko <slava@dubeyko.com>
Cc: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The variable is defined but not used.  Generally it compiles away with
-O2 optimization hence it does not show a warning.
Signed-off-by: Sougata Santra <sougata@tuxera.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Project's web site was moved to nilfs.sourceforge.net from
www.nilfs.org.  This updates the site information in
Documentation/filesystems/nilfs2.txt with the new location.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Also, web-page entry is updated according to relocation of project's web
site.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add code to check sizes of on-disk data of metadata files such as inode
size, segment usage size, DAT entry size, and checkpoint size.  Although
these sizes are read from disk, the current implementation doesn't check
them.

If these sizes are not sane on disk, it can cause out-of-range access to
metadata or memory access overrun on metadata block buffers due to
overflow in sundry calculations.

Both lower limit and upper limit of metadata sizes are verified to
prevent these issues.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Andreas Rohner <andreas.rohner@gmx.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add support for the FITRIM ioctl, which enables user space tools to
issue TRIM/DISCARD requests to the underlying device.  Every clean
segment within the specified range will be discarded.
Signed-off-by: Andreas Rohner <andreas.rohner@gmx.net>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add nilfs_sufile_trim_fs(), which takes an fstrim_range structure and
calls blkdev_issue_discard for every clean segment in the specified
range.  The range is truncated to file system block boundaries.
Signed-off-by: Andreas Rohner <andreas.rohner@gmx.net>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

With this ioctl the segment usage entries in the SUFILE can be updated
from userspace.

This is useful, because it allows the userspace GC to modify and update
segment usage entries for specific segments, which enables it to avoid
unnecessary write operations.

If a segment needs to be cleaned, but there is no or very little
reclaimable space in it, the cleaning operation basically degrades to a
useless moving operation.  In the end the only thing that changes is the
location of the data and a timestamp in the segment usage information.
With this ioctl the GC can skip the cleaning and update the segment
usage entries directly instead.

This is basically a shortcut to cleaning the segment.  It is still
necessary to read the segment summary information, but the writing of
the live blocks can be skipped if it's not worth it.

[konishi.ryusuke@lab.ntt.co.jp: add description of NILFS_IOCTL_SET_SUINFO ioctl]
Signed-off-by: Andreas Rohner <andreas.rohner@gmx.net>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Introduce nilfs_sufile_set_suinfo(), which expects an array of
nilfs_suinfo_update structures and updates the segment usage information
accordingly.

This is basically a helper function for the newly introduced
NILFS_IOCTL_SET_SUINFO ioctl.

[konishi.ryusuke@lab.ntt.co.jp: use put_bh() instead of brelse() because we know bh != NULL]
Signed-off-by: Andreas Rohner <andreas.rohner@gmx.net>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add the nilfs_suinfo_update structure, which contains the information
needed to update one segment usage entry.  The flags specify, which
fields need to be updated.
Signed-off-by: Andreas Rohner <andreas.rohner@gmx.net>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Update git repository entry of nilfs2 file system and maintainer's
email description.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

init_inodecache is only called by __init init_coda
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Summary:
 - all printk(KERN_foo converted to pr_foo()
 - add pr_fmt and remove redundant prefixes
 - convert befs_() to va_format (based on patch by Joe Perches)
 - remove non standard %Lu
 - use __func__ for all debugging

[akpm@linux-foundation.org: fix printk warnings, reported by Fengguang]
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Joe Perches <joe@perches.com>
Cc: Fengguang Wu <fengguang.wu@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

init_inodecache is only called by __init init_befs_fs.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Use kzalloc for clean fs_info allocation like other filesystems.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>