If we are using the standard SPI message pump (which all drivers should be
transitioning over to) then special case the message enqueue and instead of
starting the worker thread to push messages to the hardware do so in the
context of the caller if the controller is idle. This avoids a context
switch in the common case where the controller has a single user in a
single thread, for short PIO transfers there may be no need to context
switch away from the calling context to complete the transfer.

The code is a bit more complex than is desirable in part due to the need
to handle drivers not using the standard queue and in part due to handling
the various combinations of bus locking and asynchronous submission in
interrupt context.

It is still suboptimal since it will still wake the message pump for each
transfer in order to schedule idling of the hardware and if multiple
contexts are using the controller simultaneously a caller may end up
pumping a message for some random other thread rather than for itself,
and if the thread ends up deferring due to another context idling the
hardware then it will just busy wait.  It can, however, have the benefit
of aggregating power up and down of the hardware when a caller performs
a series of transfers back to back without any need for the use of
spi_async().
Signed-off-by: NMark Brown <broonie@kernel.org>

cur_msg is updated under the queue lock and holds the message we are
currently processing. Since currently we only ever do removals in the
pump kthread it doesn't matter in what order we do things but we want
to be able to push things out from the submitting thread so pull the
check to see if we're currently handling a message before we check to
see if the queue is idle.
Signed-off-by: NMark Brown <broonie@kernel.org>

Since most devices now do use the standard queue and in order to avoid
initialisation ordering issues being introduced by further refactorings
to improve performance move the initialisation of the queue and the lock
for it to the main master allocation.
Signed-off-by: NMark Brown <broonie@kernel.org>

Merge remote-tracking branches 'spi/topic/mxs', 'spi/topic/pxa', 'spi/topic/rockchip', 'spi/topic/samsung' and 'spi/topic/sirf' into spi-next

Merge remote-tracking branches 'spi/topic/fsl-dspi', 'spi/topic/fsl-espi', 'spi/topic/gpio', 'spi/topic/img-spfi' and 'spi/topic/meson' into spi-next

Merge remote-tracking branches 'spi/topic/atmel', 'spi/topic/cadence', 'spi/topic/dw' and 'spi/topic/fsl-cpm' into spi-next

Pull libata fixes from Tejun Heo:
 "Three libata fixes for v3.18.  Nothing too interesting.  PCI ID ID and
  quirk additions to ahci and an error handling path fix in sata_fsl"

* 'for-3.18-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata:
  ahci: disable MSI on SAMSUNG 0xa800 SSD
  sata_fsl: fix error handling of irq_of_parse_and_map
  AHCI: Add DeviceIDs for Sunrise Point-LP SATA controller

The device already asks the core to hold a runtime PM reference while it
is active so it is redundant to open code that in the driver itself.
Signed-off-by: NMark Brown <broonie@kernel.org>

Pull watchdog fix from Wim Van Sebroeck:
 "Fix the watchdog mask bit offset for Exynos7"

* git://www.linux-watchdog.org/linux-watchdog:
  watchdog: s3c2410_wdt: Fix the mask bit offset for Exynos7

Pull i2c fixes from Wolfram Sang:
 "Here are two more driver bugfixes for I2C which would be good to have"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: cadence: Set the hardware time-out register to maximum value
  i2c: davinci: generate STP always when NACK is received

The watchdog mask bit offset listed for Exynos7 is incorrect.
Fix this.
Signed-off-by: NAbhilash Kesavan <a.kesavan@samsung.com>
Acked-by: Naveen Krishna Chatradhi <naveenkrishna.ch@gmail.com
Reviewd-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

Pull x86 fixes from Thomas Gleixner:
 "Two final fixlets for 3.18:
   - Prevent microcode reload wreckage on 32bit
   - Unbreak cross compilation"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, microcode: Limit the microcode reloading to 64-bit for now
  x86: Use $(OBJDUMP) instead of plain objdump

Pull sound fixlet from Takashi Iwai:
 "Just one commit for adding a copule of HD-audio quirk entries"

* tag 'sound-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: hda/realtek - Add headset Mic support for new Dell machine

Pull drm intel fixes from Dave Airlie:
 "Two intel stable fixes, that should be it from me for this round"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/i915: Unlock panel even when LVDS is disabled
  drm/i915: More cautious with pch fifo underruns

Pull ACPI backlight fix from Rafael Wysocki:
 "This is a simple fix for an ACPI backlight regression introduced by a
  recent commit that overlooked a corner case which should have been
  taken into account"

* tag 'pm+acpi-3.18-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / video: update condition to check if device is in _DOD list

Silence some pch fifo underrun reports and panel locking backtraces,
both cc: stable.

* tag 'drm-intel-fixes-2014-12-04' of git://anongit.freedesktop.org/drm-intel:
  drm/i915: Unlock panel even when LVDS is disabled
  drm/i915: More cautious with pch fifo underruns

Pull media fixes from Mauro Carvalho Chehab:
 "A core fix and some driver fixes:
   - regression fix in Remote Controller core affecting RC6 protocol
     handling
   - fix video buffer handling in cx23885
   - race fix in solo6x10
   - fix image selection in smiapp
   - fix reported payload size on s2255drv
   - two updates for MAINTAINERS file"

* tag 'media/v3.18-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
  [media] rc-core: fix toggle handling in the rc6 decoder
  MAINTAINERS: Update mchehab's addresses
  [media] cx23885: use sg = sg_next(sg) instead of sg++
  [media] s2255drv: fix payload size for JPG, MJPEG
  [media] Update MAINTAINERS for solo6x10
  [media] solo6x10: fix a race in IRQ handler
  [media] smiapp: Only some selection targets are settable

A typo "header=y" was introduced by commit 7071cf7f ("uapi: add
missing network related headers to kbuild").
Signed-off-by: NMasahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove an unused variable assignment.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Since commit c592becb ("spi: fsl-(e)spi: migrate to generic master
queueing") the function fsl_spi_do_one_msg() is not void anymore, so return
an error code to avoid the following buid warning:

   drivers/spi/spi-fsl-spi.c: In function 'fsl_spi_do_one_msg':
>> drivers/spi/spi-fsl-spi.c:374:4: warning: 'return' with no value, in function returning non-void [-Wreturn-type]
       return;
       ^
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

kthread_run() could return ERR_PTR(-EINTR) from kthread_create_on_node().
Return the actual error code in spi_init_queue() instead of mangling it to
-ENOMEM.
Signed-off-by: NJarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

Cadence I2C controller has bug wherein it generates invalid read transactions
after timeout in master receiver mode. This driver does not use the HW
timeout and this interrupt is disabled but the feature itself cannot be
disabled. Hence, this patch writes the maximum value (0xFF) to this register.
This is one of the workarounds to this bug and it will not avoid the issue
completely but reduces the chances of error.
Signed-off-by: NVishnu Motghare <vishnum@xilinx.com>
Signed-off-by: NHarini Katakam <harinik@xilinx.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org

According to I2C specification the NACK should be handled as follows:
"When SDA remains HIGH during this ninth clock pulse, this is defined as the Not
Acknowledge signal. The master can then generate either a STOP condition to
abort the transfer, or a repeated START condition to start a new transfer."
[I2C spec Rev. 6, 3.1.6: http://www.nxp.com/documents/user_manual/UM10204.pdf]

Currently the Davinci i2c driver interrupts the transfer on receipt of a
NACK but fails to send a STOP in some situations and so makes the bus
stuck until next I2C IP reset (idle/enable).

For example, the issue will happen during SMBus read transfer which
consists from two i2c messages write command/address and read data:

S Slave Address Wr A Command Code A Sr Slave Address Rd A D1..Dn A P
<--- write -----------------------> <--- read --------------------->

The I2C client device will send NACK if it can't recognize "Command Code"
and it's expected from I2C master to generate STP in this case.
But now, Davinci i2C driver will just exit with -EREMOTEIO and STP will
not be generated.

Hence, fix it by generating Stop condition (STP) always when NACK is received.

This patch fixes Davinci I2C in the same way it was done for OMAP I2C
commit cda2109a ("i2c: omap: query STP always when NACK is received").
Reviewed-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Reported-by: NHein Tibosch <hein_tibosch@yahoo.es>
Signed-off-by: NGrygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org

Just like 0x1600 which got blacklisted by 66a7cbc3 ("ahci: disable
MSI instead of NCQ on Samsung pci-e SSDs on macbooks"), 0xa800 chokes
on NCQ commands if MSI is enabled.  Disable MSI.
Signed-off-by: NTejun Heo <tj@kernel.org>
Reported-by: NDominik Mierzejewski <dominik@greysector.net>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=89171
Cc: stable@vger.kernel.org

It appears that some SCHEDULE_USER (asm for schedule_user) callers
in arch/x86/kernel/entry_64.S are called from RCU kernel context,
and schedule_user will return in RCU user context.  This causes RCU
warnings and possible failures.

This is intended to be a minimal fix suitable for 3.18.
Reported-and-tested-by: NDave Jones <davej@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NAndy Lutomirski <luto@amacapital.net>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Pull i2c bugfixes from Wolfram Sang:
 "A few driver bugfixes for 3.18"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: omap: fix i207 errata handling
  i2c: designware: prevent early stop on TX FIFO empty
  i2c: omap: fix NACK and Arbitration Lost irq handling

Pull PCI fix from Bjorn Helgaas:
 "This fixes a Tegra20 regression that we introduced during the v3.18
  merge window"

* tag 'pci-v3.18-fixes-4' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  PCI: tegra: Use physical range for I/O mapping

Pull devicetree bugfix from Grant Likely:
 "One more bug fix for v3.18.  I debated whether or not to send you this
  merge request because we're at such a late rc.  The bug isn't critical
  in that there is only one system known to be affected and the patch is
  easy to backport.  The codepath is used by pretty much every DT based
  system, so there is risk a of regression (it /should/ be safe, but
  I've been bitten by stuff that should be safe before).  I've had it in
  linux-next for a week and haven't received any complaints.

  I think it probably should just be merged right away rather than
  waiting for the merge window and backporting.  It does fix a real bug
  and the code is theoretically safer after the change.  I can't think
  of any situation where it would be dangerous to reserve the DT memory
  an extra time.

  Summary from tag:

    Single bugfix for boot failure seen in the wild.  The memory reserve
    code tries to be clever about reserving the FDT, but it should just
    go ahead and reserve it unconditionally to avoid the problem of
    partial overlap described in the patch"

* tag 'devicetree-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/glikely/linux:
  of/fdt: memblock_reserve /memreserve/ regions in the case of partial overlap

Pull block core regression fix from Jens Axboe:
 "Single fix for a regression introduced in this development cycle,
  where dm on top of dif/dix is broken.  From Darrick Wong"

* 'for-linus' of git://git.kernel.dk/linux-block:
  block: fix regression where bio_integrity_process uses wrong bio_vec iterator

Pull drm fixes from Dave Airlie:
 "Radeon and Nouveau fixes:

  So nouveau had a few regression introduced, Ben and Maarten finally
  tracked down the one that was causing problems on my MacBookPro, also
  nvidia gave some info on the an engine we were using incorrectly, so
  disable our use of it, and one regresion with pci hotplug affecting
  optimus users.

  Radeon has an oops fixs, sync fix, and one workaround to avoid broken
  functionality on 32-bit x86, this needs better root causing and a
  better fix, but the bandaid is a lot safer at this point"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/radeon: kernel panic in drm_calc_vbltimestamp_from_scanoutpos with 3.18.0-rc6
  drm/radeon: Ignore RADEON_GEM_GTT_WC on 32-bit x86
  drm/radeon: sync all BOs involved in a CS v2
  nouveau: move the hotplug ignore to correct place.
  drm/nouveau/gf116: remove copy1 engine
  drm/nouveau: prevent stale fence->channel pointers, and protect with rcu
  drm/nouveau/fifo/g84-: ack non-stall interrupt before handling it

Pull networking fixes from David Miller:

 1) Fill in ethtool link parameters for all link types in cxgb4, from
    Hariprasad Shenai.

 2) Fix probe regressions in stmmac driver, from Huacai Chen.

 3) Network namespace leaks on errirs in rtnetlink, from Nicolas
    Dichtel.

 4) Remove erroneous BUG check which can actually trigger legitimately,
    in xen-netfront.  From Seth Forshee.

 5) Validate length of IFLA_BOND_ARP_IP_TARGET netlink attributes, from
    Thomas Grag.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
  cxgb4: Fill in supported link mode for SFP modules
  xen-netfront: Remove BUGs on paged skb data which crosses a page boundary
  sh_eth: Fix sleeping function called from invalid context
  stmmac: platform: Move plat_dat checking earlier
  sh_eth: Fix skb alloc size and alignment adjust rule.
  rtnetlink: release net refcnt on error in do_setlink()
  bond: Check length of IFLA_BOND_ARP_IP_TARGET attributes

Pull keyring/nfs fixes from James Morris:
 "From David Howells:

  The first one fixes the handling of maximum buffer size for key
  descriptions, fixing the size at 4095 + NUL char rather than whatever
  PAGE_SIZE happens to be and permits you to read back the full
  description without it getting clipped because some extra information
  got prepended.

  The second and third fix a bug in NFS idmapper handling whereby a key
  representing a mapping between an id and a name expires and causing
  EKEYEXPIRED to be seen internally in NFS (which prevents the mapping
  from happening) rather than re-looking up the mapping"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  KEYS: request_key() should reget expired keys rather than give EKEYEXPIRED
  KEYS: Simplify KEYRING_SEARCH_{NO,DO}_STATE_CHECK flags
  KEYS: Fix the size of the key description passed to/from userspace

Merge misc fixes from Andrew Morton:
 "10 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  slab: fix nodeid bounds check for non-contiguous node IDs
  lib/genalloc.c: export devm_gen_pool_create() for modules
  mm: fix anon_vma_clone() error treatment
  mm: fix swapoff hang after page migration and fork
  fat: fix oops on corrupted vfat fs
  ipc/sem.c: fully initialize sem_array before making it visible
  drivers/input/evdev.c: don't kfree() a vmalloc address
  mm/vmpressure.c: fix race in vmpressure_work_fn()
  mm: frontswap: invalidate expired data on a dup-store failure
  mm: do not overwrite reserved pages counter at show_mem()

The bounds check for nodeid in ____cache_alloc_node gives false
positives on machines where the node IDs are not contiguous, leading to
a panic at boot time.  For example, on a POWER8 machine the node IDs are
typically 0, 1, 16 and 17.  This means that num_online_nodes() returns
4, so when ____cache_alloc_node is called with nodeid = 16 the VM_BUG_ON
triggers, like this:

  kernel BUG at /home/paulus/kernel/kvm/mm/slab.c:3079!
  Call Trace:
    .____cache_alloc_node+0x5c/0x270 (unreliable)
    .kmem_cache_alloc_node_trace+0xdc/0x360
    .init_list+0x3c/0x128
    .kmem_cache_init+0x1dc/0x258
    .start_kernel+0x2a0/0x568
    start_here_common+0x20/0xa8

To fix this, we instead compare the nodeid with MAX_NUMNODES, and
additionally make sure it isn't negative (since nodeid is an int).  The
check is there mainly to protect the array dereference in the get_node()
call in the next line, and the array being dereferenced is of size
MAX_NUMNODES.  If the nodeid is in range but invalid (for example if the
node is off-line), the BUG_ON in the next line will catch that.

Fixes: 14e50c6a ("mm: slab: Verify the nodeid passed to ____cache_alloc_node")
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Reviewed-by: NYasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Reviewed-by: NPekka Enberg <penberg@kernel.org>
Acked-by: NDavid Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Modules can use this function for creating pool.
Signed-off-by: NMichal Simek <michal.simek@xilinx.com>
Acked-by: NLad, Prabhakar <prabhakar.csengg@gmail.com>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Olof Johansson <olof@lixom.net>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Andrew Morton noticed that the error return from anon_vma_clone() was
being dropped and replaced with -ENOMEM (which is not itself a bug
because the only error return value from anon_vma_clone() is -ENOMEM).

I did an audit of callers of anon_vma_clone() and discovered an actual
bug where the error return was being lost.  In __split_vma(), between
Linux 3.11 and 3.12 the code was changed so the err variable is used
before the call to anon_vma_clone() and the default initial value of
-ENOMEM is overwritten.  So a failure of anon_vma_clone() will return
success since err at this point is now zero.

Below is a patch which fixes this bug and also propagates the error
return value from anon_vma_clone() in all cases.

Fixes: ef0855d3 ("mm: mempolicy: turn vma_set_policy() into vma_dup_policy()")
Signed-off-by: NDaniel Forrest <dan.forrest@ssec.wisc.edu>
Reviewed-by: NMichal Hocko <mhocko@suse.cz>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Tim Hartrick <tim@edgecast.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: <stable@vger.kernel.org>	[3.12+]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>