generic_handler_irq() already tests for !desc so use this instead of
generic_handle_irq_desc().

Use irq_get_irq_data() instead of desc->irq_data.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Xen <xen-devel@lists.xenproject.org>
Link: http://lkml.kernel.org/r/20140223212738.222412125@linutronix.deSigned-off-by: Thomas Gleixner <tglx@linutronix.de>

The pm-mmp2 and pm-pxa910 power management related irq_set_wake
callbacks fiddle pointlessly with the irq actions for no reason except
for lack of understanding how the wakeup mechanism works.

On supsend the core disables all interrupts lazily, i.e. it does not
mask them at the irq controller level. So any interrupt which is
firing during suspend will mark the corresponding interrupt line as
pending. Just before the core powers down it checks whether there are
interrupts pending from interrupt lines which are marked as wakeup
sources and if so it aborts the suspend and resends the interrupts.
If there was no interrupt at this point, the cpu goes into suspend
with these interrupts unmasked.

The IRQF_NO_SUSPEND flag for interrupt actions is a totally different
mechanism. That allows the device driver to prevent the core from
disabling the interrupt despite the fact that it is not marked as a
wakeup source. This has nothing to do with the case at hand. It was
introduced for special cases where lazy disable is not possible.

Remove the nonsense along with the braindamaged boundary check. The
core code does NOT call these functions out of boundary.

Add a FIXME comment to an unhandled error path which merily printks
some useless blurb instead of returning a proper error code.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: arm <linux-arm-kernel@lists.infradead.org>
Cc: Eric Miao <eric.y.miao@gmail.com>
Cc: Haojian Zhuang <haojian.zhuang@gmail.com>
Cc: Russell King <linux@arm.linux.org.uk>
Link: http://lkml.kernel.org/r/20140223212737.214342433@linutronix.deSigned-off-by: Thomas Gleixner <tglx@linutronix.de>

Use the proper functions. There is no need to fiddle with irq_desc.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Shawn Guo <shawn.guo@linaro.org>C
Acked-by: Tony Lindgren <tony@atomide.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: arm <linux-arm-kernel@lists.infradead.org>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Link: http://lkml.kernel.org/r/20140223212737.099151500@linutronix.deSigned-off-by: Thomas Gleixner <tglx@linutronix.de>

There is no reason to care about irq_desc in that context, escpecially
as irq_data for that interrupt is retrieved as well.

Use the proper accessor for the msi descriptor
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Jingoo Han <jg1.han@samsung.com>
Cc: Mohit Kumar <mohit.kumar@st.com>
Cc: pci <linux-pci@vger.kernel.org>
Link: http://lkml.kernel.org/r/20140223212736.987803648@linutronix.deSigned-off-by: Thomas Gleixner <tglx@linutronix.de>

commit 91150af3 (powerpc/eeh: Fix unbalanced enable for IRQ) is
another brilliant example of trainwreck engineering.

The patch "fixes" the issue of an unbalanced call to irq_enable()
which causes a prominent warning by checking the disabled state of the
interrupt line and call conditionally into the core code.

This is wrong in two aspects:

1) The warning is there to tell users, that they need to fix their
   asymetric enable/disable patterns by finding the root cause and
   solving it there.

   It's definitely not meant to work around it by conditionally
   calling into the core code depending on the random state of the irq
   line.

   Asymetric irq_disable/enable calls are a clear sign of wrong usage
   of the interfaces which have to be cured at the root and not by
   somehow hacking around it.

2) The abuse of core internal data structure instead of using the
   proper interfaces for retrieving the information for the 'hack
   around'

   irq_desc is core internal and it's clear enough stated.

Replace at least the irq_desc abuse with the proper functions and add
a big fat comment why this is absurd and completely wrong.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Gavin Shan <shangw@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: ppc <linuxppc-dev@lists.ozlabs.org>
Link: http://lkml.kernel.org/r/20140223212736.562906212@linutronix.deSigned-off-by: Thomas Gleixner <tglx@linutronix.de>

No functional change
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: ppc <linuxppc-dev@lists.ozlabs.org>
Link: http://lkml.kernel.org/r/20140223212736.333718121@linutronix.deSigned-off-by: Thomas Gleixner <tglx@linutronix.de>

I'm really grumpy about this one. The line:

#include "../../../kernel/irq/settings.h"

should have been an alarm sign for all people who added their SOB to
this trainwreck.

When I cleaned up the mess people made with interrupt descriptors a
few years ago, I warned that I'm going to hunt down new offenders and
treat them with stinking trouts. In this case I'll use frozen shark
for a better educational value.

The whole idiocy which was done there could have been avoided with two
lines of perfectly fine code. And do not complain about the lack of
correct examples in tree.

The solution is simple:

  Remove the brainfart and use the proper functions, which should
  have been used in the first place
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Ashish Kalra <ashish.kalra@freescale.com>
Cc: Timur Tabi <timur@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: ppc <linuxppc-dev@lists.ozlabs.org>
Link: http://lkml.kernel.org/r/20140223212736.451970660@linutronix.deSigned-off-by: Thomas Gleixner <tglx@linutronix.de>

This reverts commit 40b367d9.

Russell King has raised the idea of creating a proper PMU driver for
this SoC that would incorporate the functionality currently in this
driver. It would also cover the use case for the graphics subsystem on
this SoC.

To prevent having to maintain the devicetree ABI for this limited
interrupt-handler driver, we revert the driver before it hits a mainline
tagged release (eg v3.15).
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@googlemail.com>
Cc: Gregory CLEMENT <gregory.clement@free-electrons.com>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
Link: http://lkml.kernel.org/r/1393911160-7688-1-git-send-email-jason@lakedaemon.netSigned-off-by: Thomas Gleixner <tglx@linutronix.de>

irqchip mvebu changes for v3.15

 - armada-370-xp
    - add MSI helper
    - MPIC chained handler
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

The new Armada 375 and Armada 38x Marvell SoCs are based on Cortex-A9
CPU cores and use the ARM GIC as their main interrupt controller.
However, for various purposes (wake-up from suspend, MSI interrupts),
they have kept a separate MPIC interrupt controller, acting as a slave
to the GIC. This MPIC was already used as the primary controller on
previous Marvell SoCs, so this commit extends the existing driver to
allow the MPIC to be used as a GIC slave.
Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

Introduce a helper function to handle the MSI interrupts. This makes
the code more readable. In addition, this will allow to introduce a
chained IRQ handler mechanism, which is needed in situations where the
MPIC is used as a slave to another interrupt controller.
Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

mvebu irqchip fixes for v3.13

 - armada-370-xp
    - fix races is MSI and IPI

Change the comment "chasnge" to "change".
Signed-off-by: Chuansheng Liu <chuansheng.liu@intel.com>
Link: http://lkml.kernel.org/r/1392020037-5484-2-git-send-email-chuansheng.liu@intel.comSigned-off-by: Thomas Gleixner <tglx@linutronix.de>

Pull the functionality which is required to cleanup sdhci/sdio
in. It's in a separate branch so it can be pulled from others
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

In course of the sdhci/sdio discussion with Russell about killing the
sdio kthread hackery we discovered the need to be able to wake an
interrupt thread from software.

The rationale for this is, that sdio hardware can lack proper
interrupt support for certain features. So the driver needs to poll
the status registers, but at the same time it needs to be woken up by
an hardware interrupt.

To be able to get rid of the home brewn kthread construct of sdio we
need a way to wake an irq thread independent of an actual hardware
interrupt.

Provide an irq_wake_thread() function which wakes up the thread which
is associated to a given dev_id. This allows sdio to invoke the irq
thread from the hardware irq handler via the IRQ_WAKE_THREAD return
value and provides a possibility to wake it via a timer for the
polling scenarios. That allows to simplify the sdio logic
significantly.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Chris Ball <chris@printf.net>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140215003823.772565780@linutronix.de

synchronize_irq() waits for hard irq and threaded handlers to complete
before returning. For some special cases we only need to make sure
that the hard interrupt part of the irq line is not in progress when
we disabled the - possibly shared - interrupt at the device level.

A proper use case for this was provided by Russell. The sdhci driver
requires some irq triggered functions to be run in thread context. The
current implementation of the thread context is a sdio private kthread
construct, which has quite some shortcomings. These can be avoided
when the thread is directly associated to the device interrupt via the
generic threaded irq infrastructure.

Though there is a corner case related to run time power management
where one side disables the device interrupts at the device level and
needs to make sure, that an already running hard interrupt handler has
completed before proceeding further. Though that hard interrupt
handler might wake the associated thread, which in turn can request
the runtime PM to reenable the device. Using synchronize_irq() leads
to an immediate deadlock of the irq thread waiting for the PM lock and
the synchronize_irq() waiting for the irq thread to complete.

Due to the fact that it is sufficient for this case to ensure that no
hard irq handler is executing a new function which avoids the check
for the thread is required.

Add a function, which just monitors the hard irq parts and ignores the
threaded handlers.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Russell King <linux@arm.linux.org.uk>
Cc: Chris Ball <chris@printf.net>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20140215003823.653236081@linutronix.de

mvebu irqchip changes for v3.14

 - add Dove PMU interrupt controller

Duh. I completely forgot about that one...
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Pull btrfs fixes from Chris Mason:
 "We have a small collection of fixes in my for-linus branch.

  The big thing that stands out is a revert of a new ioctl.  Users
  haven't shipped yet in btrfs-progs, and Dave Sterba found a better way
  to export the information"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: use right clone root offset for compressed extents
  btrfs: fix null pointer deference at btrfs_sysfs_add_one+0x105
  Btrfs: unset DCACHE_DISCONNECTED when mounting default subvol
  Btrfs: fix max_inline mount option
  Btrfs: fix a lockdep warning when cleaning up aborted transaction
  Revert "btrfs: add ioctl to export size of global metadata reservation"

Pull devicetree fixes from Rob Herring:
 "Fix booting on PPC boards.  Changes to of_match_node matching caused
  the serial port on some PPC boards to stop working.  Reverted the
  change and reimplement to split matching between new style compatible
  only matching and fallback to old matching algorithm"

* tag 'dt-fixes-for-3.14' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
  of: search the best compatible match first in __of_match_node()
  Revert "OF: base: match each node compatible against all given matches first"

Currently, of_match_node compares each given match against all node's
compatible strings with of_device_is_compatible.

To achieve multiple compatible strings per node with ordering from
specific to generic, this requires given matches to be ordered from
specific to generic. For most of the drivers this is not true and also
an alphabetical ordering is more sane there.

Therefore, this patch introduces a function to match each of the node's
compatible strings against all given compatible matches without type and
name first, before checking the next compatible string. This implies
that node's compatibles are ordered from specific to generic while
given matches can be in any order. If we fail to find such a match
entry, then fall-back to the old method in order to keep compatibility.

Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Tested-by: Stephen Chivers <schivers@csc.com>
Signed-off-by: Rob Herring <robh@kernel.org>

Pull SCSI target fixes from Nicholas Bellinger:
 "Mostly minor fixes this time to v3.14-rc1 related changes.  Also
  included is one fix for a free after use regression in persistent
  reservations UNREGISTER logic that is CC'ed to >= v3.11.y stable"

* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
  Target/sbc: Fix protection copy routine
  IB/srpt: replace strict_strtoul() with kstrtoul()
  target: Simplify command completion by removing CMD_T_FAILED flag
  iser-target: Fix leak on failure in isert_conn_create_fastreg_pool
  iscsi-target: Fix SNACK Type 1 + BegRun=0 handling
  target: Fix missing length check in spc_emulate_evpd_83()
  qla2xxx: Remove last vestiges of qla_tgt_cmd.cmd_list
  target: Fix 32-bit + CONFIG_LBDAF=n link error w/ sector_div
  target: Fix free-after-use regression in PR unregister

Pull i2c fixes from Wolfram Sang:
 "i2c has a bugfix and documentation improvements for you"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  Documentation: i2c: mention ACPI method for instantiating devices
  Documentation: i2c: describe devicetree method for instantiating devices
  i2c: mv64xxx: refactor message start to ensure proper initialization

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

Pull irq update from Thomas Gleixner:
 "Fix from the urgent branch: a trivial oneliner adding the missing
  Kconfig dependency curing build failures which have been discovered by
  several build robots.

  The update in the irq-core branch provides a new function in the
  irq/devres code, which is a prerequisite for driver developers to get
  rid of boilerplate code all over the place.

  Not a bugfix, but it has zero impact on the current kernel due to the
  lack of users.  It's simpler to provide the infrastructure to
  interested parties via your tree than fulfilling the wishlist of
  driver maintainers on which particular commit or tag this should be
  based on"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Add missing irq_to_desc export for CONFIG_SPARSE_IRQ=n

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Add devm_request_any_context_irq()

Pull timer fixes from Thomas Gleixner:
 "The following trilogy of patches brings you:

   - fix for a long standing math overflow issue with HZ < 60

   - an onliner fix for a corner case in the dreaded tick broadcast
     mechanism affecting a certain range of AMD machines which are
     infested with the infamous automagic C1E power control misfeature

   - a fix for one of the ARM platforms which allows the kernel to
     proceed and boot instead of stupidly panicing for no good reason.
     The patch is slightly larger than necessary, but it's less ugly
     than the alternative 5 liner"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tick: Clear broadcast pending bit when switching to oneshot
  clocksource: Kona: Print warning rather than panic
  time: Fix overflow when HZ is smaller than 60

Merge tag 'trace-fixes-v3.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull twi tracing fixes from Steven Rostedt:
 "Two urgent fixes in the tracing utility.

  The first is a fix for the way the ring buffer stores timestamps.
  After a restructure of the code was done, the ring buffer timestamp
  logic missed the fact that the first event on a sub buffer is to have
  a zero delta, as the full timestamp is stored on the sub buffer
  itself.  But because the delta was not cleared to zero, the timestamp
  for that event will be calculated as the real timestamp + the delta
  from the last timestamp.  This can skew the timestamps of the events
  and have them say they happened when they didn't really happen.
  That's bad.

  The second fix is for modifying the function graph caller site.  When
  the stop machine was removed from updating the function tracing code,
  it missed updating the function graph call site location.  It is still
  modified as if it is being done via stop machine.  But it's not.  This
  can lead to a GPF and kernel crash if the function graph call site
  happens to lie between cache lines and one CPU is executing it while
  another CPU is doing the update.  It would be a very hard condition to
  hit, but the result is severe enough to have it fixed ASAP"

* tag 'trace-fixes-v3.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  ftrace/x86: Use breakpoints for converting function graph caller
  ring-buffer: Fix first commit on sub-buffer having non-zero delta

Pull x86 EFI fixes from Peter Anvin:
 "A few more EFI-related fixes"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/efi: Check status field to validate BGRT header
  x86/efi: Fix 32-bit fallout

Pull ARM SoC fixes from Kevin Hilman:
 "A collection of ARM SoC fixes for v3.14-rc1.

  Mostly a collection of Kconfig, device tree data and compilation fixes
  along with fix to drivers/phy that fixes a boot regression on some
  Marvell mvebu platforms"

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  dma: mv_xor: Silence a bunch of LPAE-related warnings
  ARM: ux500: disable msp2 device tree node
  ARM: zynq: Reserve not DMAable space in front of the kernel
  ARM: multi_v7_defconfig: Select CONFIG_SOC_DRA7XX
  ARM: imx6: Initialize low-power mode early again
  ARM: pxa: fix various compilation problems
  ARM: pxa: fix compilation problem on AM300EPD board
  ARM: at91: add Atmel's SAMA5D3 Xplained board
  spi/atmel: document clock properties
  mmc: atmel-mci: document clock properties
  ARM: at91: enable USB host on at91sam9n12ek board
  ARM: at91/dt: fix sama5d3 ohci hclk clock reference
  ARM: at91/dt: sam9263: fix compatibility string for the I2C
  ata: sata_mv: Fix probe failures with optional phys
  drivers: phy: Add support for optional phys
  drivers: phy: Make NULL a valid phy reference
  ARM: fix HAVE_ARM_TWD selection for OMAP and shmobile
  ARM: moxart: move DMA_OF selection to driver
  ARM: hisi: fix kconfig warning on HAVE_ARM_TWD

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Guenter Roeck <linux@roeck-us.net>

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

For non compressed extents, iterate_extent_inodes() gives us offsets
that take into account the data offset from the file extent items, while
for compressed extents it doesn't. Therefore we have to adjust them before
placing them in a send clone instruction. Not doing this adjustment leads to
the receiving end requesting for a wrong a file range to the clone ioctl,
which results in different file content from the one in the original send
root.

Issue reproducible with the following excerpt from the test I made for
xfstests:

  _scratch_mkfs
  _scratch_mount "-o compress-force=lzo"

  $XFS_IO_PROG -f -c "truncate 118811" $SCRATCH_MNT/foo
  $XFS_IO_PROG -c "pwrite -S 0x0d -b 39987 92267 39987" $SCRATCH_MNT/foo

  $BTRFS_UTIL_PROG subvolume snapshot -r $SCRATCH_MNT $SCRATCH_MNT/mysnap1

  $XFS_IO_PROG -c "pwrite -S 0x3e -b 80000 200000 80000" $SCRATCH_MNT/foo
  $BTRFS_UTIL_PROG filesystem sync $SCRATCH_MNT
  $XFS_IO_PROG -c "pwrite -S 0xdc -b 10000 250000 10000" $SCRATCH_MNT/foo
  $XFS_IO_PROG -c "pwrite -S 0xff -b 10000 300000 10000" $SCRATCH_MNT/foo

  # will be used for incremental send to be able to issue clone operations
  $BTRFS_UTIL_PROG subvolume snapshot -r $SCRATCH_MNT $SCRATCH_MNT/clones_snap

  $BTRFS_UTIL_PROG subvolume snapshot -r $SCRATCH_MNT $SCRATCH_MNT/mysnap2

  $FSSUM_PROG -A -f -w $tmp/1.fssum $SCRATCH_MNT/mysnap1
  $FSSUM_PROG -A -f -w $tmp/2.fssum -x $SCRATCH_MNT/mysnap2/mysnap1 \
      -x $SCRATCH_MNT/mysnap2/clones_snap $SCRATCH_MNT/mysnap2
  $FSSUM_PROG -A -f -w $tmp/clones.fssum $SCRATCH_MNT/clones_snap \
      -x $SCRATCH_MNT/clones_snap/mysnap1 -x $SCRATCH_MNT/clones_snap/mysnap2

  $BTRFS_UTIL_PROG send $SCRATCH_MNT/mysnap1 -f $tmp/1.snap
  $BTRFS_UTIL_PROG send $SCRATCH_MNT/clones_snap -f $tmp/clones.snap
  $BTRFS_UTIL_PROG send -p $SCRATCH_MNT/mysnap1 \
      -c $SCRATCH_MNT/clones_snap $SCRATCH_MNT/mysnap2 -f $tmp/2.snap

  _scratch_unmount
  _scratch_mkfs
  _scratch_mount

  $BTRFS_UTIL_PROG receive $SCRATCH_MNT -f $tmp/1.snap
  $FSSUM_PROG -r $tmp/1.fssum $SCRATCH_MNT/mysnap1 2>> $seqres.full

  $BTRFS_UTIL_PROG receive $SCRATCH_MNT -f $tmp/clones.snap
  $FSSUM_PROG -r $tmp/clones.fssum $SCRATCH_MNT/clones_snap 2>> $seqres.full

  $BTRFS_UTIL_PROG receive $SCRATCH_MNT -f $tmp/2.snap
  $FSSUM_PROG -r $tmp/2.fssum $SCRATCH_MNT/mysnap2 2>> $seqres.full
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>

bdev is null when disk has disappeared and mounted with
the degrade option

stack trace
---------
btrfs_sysfs_add_one+0x105/0x1c0 [btrfs]
open_ctree+0x15f3/0x1fe0 [btrfs]
btrfs_mount+0x5db/0x790 [btrfs]
? alloc_pages_current+0xa4/0x160
mount_fs+0x34/0x1b0
vfs_kern_mount+0x62/0xf0
do_mount+0x22e/0xa80
? __get_free_pages+0x9/0x40
? copy_mount_options+0x31/0x170
SyS_mount+0x7e/0xc0
system_call_fastpath+0x16/0x1b
---------

reproducer:
-------
mkfs.btrfs -draid1 -mraid1 /dev/sdc /dev/sdd
(detach a disk)
devmgt detach /dev/sdc [1]
mount -o degrade /dev/sdd /btrfs
-------

[1] github.com/anajain/devmgt.git
Signed-off-by: Anand Jain <Anand.Jain@oracle.com>
Tested-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>

Because the offload mechanism can fall back to a standard transfer,
having two seperate initialization states is unfortunate. Let's just
have one state which does things consistently. This fixes a bug where
some preparation was missing when the fallback happened. And it makes
the code much easier to follow. To implement this, we put the check
if offload is possible at the top of the offload setup function.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Tested-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Cc: stable@vger.kernel.org # v3.12+
Fixes: 930ab3d4 (i2c: mv64xxx: Add I2C Transaction Generator support)

Pull USB fixes from Greg KH:
 "Here is a bunch of USB fixes for 3.14-rc3.  Most of these are xhci
  reverts, fixing a bunch of reported issues with USB 3 host controller
  issues that loads of people have been hitting (with the exception of
  kernel developers, all of our machines seem to be working fine, which
  is why these took so long to get resolved...)

  There are some other minor fixes and new device ids, as ususal.  All
  have been in linux-next successfully"

* tag 'usb-3.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (22 commits)
  usb: option: blacklist ZTE MF667 net interface
  Revert "usb: xhci: Link TRB must not occur within a USB payload burst"
  Revert "xhci: Avoid infinite loop when sg urb requires too many trbs"
  Revert "xhci: Set scatter-gather limit to avoid failed block writes."
  xhci 1.0: Limit arbitrarily-aligned scatter gather.
  Modpost: fixed USB alias generation for ranges including 0x9 and 0xA
  usb: core: Fix potential memory leak adding dyn USBdevice IDs
  USB: ftdi_sio: add Tagsys RFID Reader IDs
  usb: qcserial: add Netgear Aircard 340U
  usb-storage: enable multi-LUN scanning when needed
  USB: simple: add Dynastream ANT USB-m Stick device support
  usb-storage: add unusual-devs entry for BlackBerry 9000
  usb-storage: restrict bcdDevice range for Super Top in Cypress ATACB
  usb: phy: move some error messages to debug
  usb: ftdi_sio: add Mindstorms EV3 console adapter
  usb: dwc2: fix memory corruption in dwc2 driver
  usb: dwc2: fix role switch breakage
  usb: dwc2: bail out early when booting with "nousb"
  Revert "xhci: replace xhci_read_64() with readq()"
  Revert "xhci: replace xhci_write_64() with writeq()"
  ...

Pull tty/serial driver fixes from Greg KH:
 "Here are a small number of tty/serial driver fixes to resolve reported
  issues with 3.14-rc and earlier (in the case of the vt bugfix).  Some
  of these have been tested and reported by a number of people as the
  tty bugfix was pretty commonly hit on some platforms.

  All have been in linux-next for a while"

* tag 'tty-3.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  vt: Fix secure clear screen
  serial: 8250: Support XR17V35x fraction divisor
  n_tty: Fix stale echo output
  serial: sirf: fix kernel panic caused by unpaired spinlock
  serial: 8250_pci: unbreak last serial ports on NetMos 9865 cards
  n_tty: Fix poll() when TIME_CHAR and MIN_CHAR == 0
  serial: omap: fix rs485 probe on defered pinctrl
  serial: 8250_dw: fix compilation warning when !CONFIG_PM_SLEEP
  serial: omap-serial: Move info message to probe function
  tty: Set correct tty name in 'active' sysfs attribute
  tty: n_gsm: Fix for modems with brk in modem status control
  drivers/tty/hvc: don't use module_init in non-modular hyp. console code

Pull staging driver fixes from Greg KH:
 "Here are a number (lots, I know) of fixes for staging drivers to
  resolve a bunch of reported issues.

  The largest patches here is one revert of a patch that is in 3.14-rc1
  to fix reported problems, and a sync of a usb host driver that
  required some ARM patches to go in before it could be accepted (which
  is why it missed -rc1)

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'staging-3.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (56 commits)
  staging/rtl8821ae: fix build, depends on MAC80211
  iio: max1363: Use devm_regulator_get_optional for optional regulator
  iio:accel:bma180: Use modifier instead of index in channel specification
  iio: adis16400: Set timestamp as the last element in chan_spec
  iio: ak8975: Fix calculation formula for convert micro tesla to gauss unit
  staging:iio:ad799x fix typo in ad799x_events[]
  iio: mxs-lradc: remove useless scale_available files
  iio: mxs-lradc: fix buffer overflow
  iio:magnetometer:mag3110: Fix output of decimal digits in show_int_plus_micros()
  iio:magnetometer:mag3110: Report busy in _read_raw() / write_raw() when buffer is enabled
  wlags49_h2: Fix overflow in wireless_set_essid()
  xlr_net: Fix missing trivial allocation check
  staging: r8188eu: overflow in rtw_p2p_get_go_device_address()
  staging: r8188eu: array overflow in rtw_mp_ioctl_hdl()
  staging: r8188eu: Fix typo in USB_DEVICE list
  usbip/userspace/libsrc/names.c: memory leak
  gpu: ion: dereferencing an ERR_PTR
  staging: comedi: usbduxsigma: fix unaligned dereferences
  staging: comedi: fix too early cleanup in comedi_auto_config()
  staging: android: ion: dummy: fix an error code
  ...

Merge tag 'driver-core-3.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core fix from Greg KH:
 "Here is a single driver core patch for 3.14-rc3 for the component code
  that Russell has found and fixed"

* tag 'driver-core-3.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  drivers/base: fix devres handling for master device

Pull char/misc fixes from Greg KH:
 "Here are some small char/misc driver fixes, along with some
  documentation updates, for 3.14-rc3.  Nothing major, just a number of
  fixes for reported issues"

* tag 'char-misc-3.14-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  Revert "misc: eeprom: sunxi: Add new compatibles"
  Revert "ARM: sunxi: dt: Convert to the new SID compatibles"
  misc: mic: fix possible signed underflow (undefined behavior) in userspace API
  ARM: sunxi: dt: Convert to the new SID compatibles
  misc: eeprom: sunxi: Add new compatibles
  misc: genwqe: Fix potential memory leak when pinning memory
  Documentation:Update Documentation/zh_CN/arm64/memory.txt
  Documentation:Update Documentation/zh_CN/arm64/booting.txt
  Documentation:Chinese translation of Documentation/arm64/tagged-pointers.txt
  raw: set range for MAX_RAW_DEVS
  raw: test against runtime value of max_raw_minors
  Drivers: hv: vmbus: Don't timeout during the initial connection with host
  Drivers: hv: vmbus: Specify the target CPU that should receive notification
  VME: Correct read/write alignment algorithm
  mei: don't unset read cb ptr on reset
  mei: clear write cb from waiting list on reset

A user was running into errors from an NFS export of a subvolume that had a
default subvol set.  When we mount a default subvol we will use d_obtain_alias()
to find an existing dentry for the subvolume in the case that the root subvol
has already been mounted, or a dummy one is allocated in the case that the root
subvol has not already been mounted.  This allows us to connect the dentry later
on if we wander into the path.  However if we don't ever wander into the path we
will keep DCACHE_DISCONNECTED set for a long time, which angers NFS.  It doesn't
appear to cause any problems but it is annoying nonetheless, so simply unset
DCACHE_DISCONNECTED in the get_default_root case and switch btrfs_lookup() to
use d_materialise_unique() instead which will make everything play nicely
together and reconnect stuff if we wander into the defaul subvol path from a
different way.  With this patch I'm no longer getting the NFS errors when
exporting a volume that has been mounted with a default subvol set.  Thanks,

cc: bfields@fieldses.org
cc: ebiederm@xmission.com
Signed-off-by: Josef Bacik <jbacik@fb.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Chris Mason <clm@fb.com>

Currently, the only mount option for max_inline that has any effect is
max_inline=0.  Any other value that is supplied to max_inline will be
adjusted to a minimum of 4k.  Since max_inline has an effective maximum
of ~3900 bytes due to page size limitations, the current behaviour
only has meaning for max_inline=0.

This patch will allow the the max_inline mount option to accept non-zero
values as indicated in the documentation.
Signed-off-by: Mitch Harder <mitch.harder@sabayonlinux.org>
Signed-off-by: Chris Mason <clm@fb.com>