sh->lock is now mainly used to ensure that two threads aren't running
in the locked part of handle_stripe[56] at the same time.

That can more neatly be achieved with an 'active' flag which we set
while running handle_stripe.  If we find the flag is set, we simply
requeue the stripe for later by setting STRIPE_HANDLE.

For safety we take ->device_lock while examining the state of the
stripe and creating a summary in 'stripe_head_state / r6_state'.
This possibly isn't needed but as shared fields like ->toread,
->towrite are checked it is safer for now at least.

We leave the label after the old 'unlock' called "unlock" because it
will disappear in a few patches, so renaming seems pointless.

This leaves the stripe 'locked' for longer as we clear STRIPE_ACTIVE
later, but that is not a problem.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>

Other places that change or follow dev->towrite and dev->written take
the device_lock as well as the sh->lock.
So it should really be held in these places too.
Also, doing so will allow sh->lock to be discarded.

with merged fixes by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>

This is the start of a series of patches to remove sh->lock.

sync_request takes sh->lock before setting STRIPE_SYNCING to ensure
there is no race with testing it in handle_stripe[56].

Instead, use a new flag STRIPE_SYNC_REQUESTED and test it early
in handle_stripe[56] (after getting the same lock) and perform the
same set/clear operations if it was set.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>

In raid5::make_request(), once bio_data_dir(@bi) is detected
it never (and couldn't) be changed. Use the result always.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>

Replace kmem_cache_alloc + memset(,0,) to kmem_cache_zalloc.
I think it's not harmful since @conf->slab_cache already knows
actual size of struct stripe_head.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>

When performing a recovery, only first 2 slots in r10_bio are in use,
for read and write respectively. However all of pages in the write bio
are never used and just replaced to read bio's when the read completes.

Get rid of those unused pages and share read pages properly.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>

When normal-write and sync-read/write bio completes, we should
find out the disk number the bio belongs to. Factor those common
code out to a separate function.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>

Variable 'first' is initialized to zero and updated to @rdev->raid_disk
only if it is greater than 0. Thus condition '>= first' always implies
'>= 0' so the latter is not needed.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>

* 'gpio/merge' of git://git.secretlab.ca/git/linux-2.6:
  gpio: wm831x: add a missing break in wm831x_gpio_dbg_show

Commit 234b6ced

   clocksource: convert ARM 32-bit up counting clocksources

broke the build for ixp4xx and made big endian operation impossible.
This commit restores the original behaviour.
Signed-off-by: Richard Cochran <richard.cochran@omicron.at>
Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl>
[ Thomas says that we might want to have generic BE accessor functions
  to the MMIO clock source, but that hasn't happened yet, so in the
  meantime this seems to be the short-term fix for the particular
  problem - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2:
  nilfs2: remove resize from unsupported features list

* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/staging:
  hwmon: (adm1275) Fix coefficients per datasheet revision B
  hwmon: (pmbus) Use long variables for register to data conversions

* 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6:
  drm/radeon/kms: add new NI pci ids

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
  fix loop checks in d_materialise_unique()
  Fix ->d_lock locking order in unlazy_walk()

* 'rcu/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-2.6-rcu:
  rcu: Prevent RCU callbacks from executing before scheduler initialized

Commit 3fe1698b ("sched: Deal with non-atomic min_vruntime reads
on 32bit") forgot to initialize min_vruntime_copy which could lead to
an infinite while loop in task_waking_fair() under some circumstances
(early boot, lucky timing).

[ This bug was also reported by others that blamed it on the RCU
  initialization problems ]
Reported-and-tested-by: Bruno Wolff III <bruno@wolff.to>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>

Coefficients to convert chip register values to voltage/current have been
slightly changed in revision B of the chip datasheet. Update driver coefficients
to match the coefficients in the datasheet.
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
Acked-by: Jean Delvare <khali@linux-fr.org>

Both __d_unalias() and __d_materialise_dentry() need loop prevention.
Grab rename_lock in caller, check for loops there...

As a side benefit, we have dentry_lock_for_move() called only under
rename_lock, which seriously reduces deadlock potential of the
execrable "locking order" used for ->d_lock.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-fixes:
  GFS2: Resolve inode eviction and ail list interaction bug
  GFS2: Fix race during filesystem mount
  GFS2: force a log flush when invalidating the rindex glock

This patch contains a few misc fixes which resolve a recently
reported issue. This patch has been a real team effort and has
received a lot of testing.

The first issue is that the ail lock needs to be held over a few
more operations. The lock thats added into gfs2_releasepage() may
possibly be a candidate for replacing with RCU at some future
point, but at this stage we've gone for the obvious fix.

The second issue is that gfs2_write_inode() can end up calling
a glock recursively when called from gfs2_evict_inode() via the
syncing code, so it needs a guard added.

The third issue is that we either need to not truncate the metadata
pages of inodes which have zero link count, but which we cannot
deallocate due to them still being in use by other nodes, or we need
to ensure that those pages have all made it through the journal and
ail lists first. This patch takes the former approach, but the
latter has also been tested and there is nothing to choose between
them performance-wise. So again, we could revise that decision
in the future.

Also, the inode eviction process is now better documented.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Tested-by: Bob Peterson <rpeterso@redhat.com>
Tested-by: Abhijith Das <adas@redhat.com>
Reported-by: Barry J. Marson <bmarson@redhat.com>
Reported-by: David Teigland <teigland@redhat.com>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc:
  mmc: core: Bus width testing needs to handle suspend/resume

* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
  SUNRPC: Fix use of static variable in rpcb_getport_async
  NFSv4.1: update nfs4_fattr_bitmap_maxsz
  SUNRPC: Fix a race between work-queue and rpc_killall_tasks
  pnfs: write: Set mds_offset in the generic layer - it is needed by all LDs

* 'rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6:
  kbuild: Do not write to builddir in modules_install

* 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6:
  drm/radeon/kms/evergreen: emit SQ_LDS_RESOURCE_MGMT for blits
  agp/intel: Fix typo in G4x_GMCH_SIZE_VT_2M
  drm/radeon/kms: fix typo in read_disabled vbios code
  drm/radeon/kms: use correct BUS_CNTL reg on rs600
  drm/radeon/kms: fix backend map typo on juniper
  drm/radeon/kms: fix regression in hotplug

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (21 commits)
  slip: fix wrong SLIP6 ifdef-endif placing
  natsemi: fix another dma-debug report
  sctp: ABORT if receive, reassmbly, or reodering queue is not empty while closing socket
  net: Fix default in docs for tcp_orphan_retries.
  hso: fix a use after free condition
  net/natsemi: Fix module parameter permissions
  XFRM: Fix memory leak in xfrm_state_update
  sctp: Enforce retransmission limit during shutdown
  mac80211: fix TKIP replay vulnerability
  mac80211: fix ie memory allocation for scheduled scans
  ssb: fix init regression of hostmode PCI core
  rtlwifi: rtl8192cu: Add new USB ID for Netgear WNA1000M
  ath9k: Fix tx throughput drops for AR9003 chips with AES encryption
  carl9170: add NEC WL300NU-AG usbid
  cfg80211: fix deadlock with rfkill/sched_scan by adding new mutex
  ath5k: fix incorrect use of drvdata in PCI suspend/resume code
  ath5k: fix incorrect use of drvdata in sysfs code
  Bluetooth: Fix memory leak under page timeouts
  Bluetooth: Fix regression with incoming L2CAP connections
  Bluetooth: Fix hidp disconnect deadlocks and lost wakeup
  ...

On reading the ext_csd for the first time (in 1 bit mode), save the
ext_csd information needed for bus width compare.

On every pass we make re-reading the ext_csd, compare the data
against the saved ext_csd data.

This fixes a regression introduced in 3.0-rc1 by 08ee80cc
("mmc: core: eMMC bus width may not work on all platforms"), which
incorrectly assumed we would be re-reading the ext_csd at resume-
time.
Signed-off-by: Philip Rakity <prakity@marvell.com>
Tested-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

Under some rare but real combinations of configuration parameters, RCU
callbacks are posted during early boot that use kernel facilities that
are not yet initialized.  Therefore, when these callbacks are invoked,
hard hangs and crashes ensue.  This commit therefore prevents RCU
callbacks from being invoked until after the scheduler is fully up and
running, as in after multiple tasks have been spawned.

It might well turn out that a better approach is to identify the specific
RCU callbacks that are causing this problem, but that discussion will
wait until such time as someone really needs an RCU callback to be invoked
(as opposed to merely registered) during early boot.
Reported-by: julie Sullivan <kernelmail.jms@gmail.com>
Reported-by: RKK <kulkarni.ravi4@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: julie Sullivan <kernelmail.jms@gmail.com>
Tested-by: RKK <kulkarni.ravi4@gmail.com>

Resize feature was supported by the commit 4e33f9ea but it was not
reflected to the list of unsupported features in nilfs2.txt file.
This updates the list to fix discrepancy.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

Compute drivers may change this, so make sure to emit it to
avoid errors in bo blits.

Fixes:
https://bugs.freedesktop.org/show_bug.cgi?id=39119Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

Konstantin Belousov found an error in the define of G4x_GMCH_SIZE_VT_2M
relative to the GMCH specs, and confirmed that indeed one of his users
with a Q45 reports 0xb not 0xc for a 2/2MiB GATT.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Konstantin Belousov <kostikbel@gmail.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>

Make sure that child is still a child of parent before nested locking
of child->d_lock in unlazy_walk(); otherwise we are risking a violation
of locking order and deadlocks.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc/mm: Fix memory_block_size_bytes() for non-pseries
  mm: Move definition of MIN_MEMORY_BLOCK_SIZE to a header

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/linux-arm-soc:
  pcmcia: pxa2xx/vpac270: free gpios on exist rather than requesting
  ARM: pxa/raumfeld: fix device name for codec ak4104
  ARM: pxa/raumfeld: display initialisation fixes
  ARM: pxa/raumfeld: adapt to upcoming hardware change
  ARM: pxa: fix gpio_to_chip() clash with gpiolib namespace
  genirq: replace irq_gc_ack() with {set,clr}_bit variants (fwd)
  arm: mach-vt8500: add forgotten irq_data conversion
  ARM: pxa168: correct nand pmu setting
  ARM: pxa910: correct nand pmu setting
  ARM: pxa: fix PGSR register address calculation

* 'drm-intel-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/keithp/linux-2.6:
  drm/i915/ringbuffer: Idling requires waiting for the ring to be empty
  Revert "drm/i915: enable rc6 by default"
  drm/i915: Clean up i915_driver_load failure path
  drm/i915: Enable GPU reset on Ivybridge.
  drm/i915/dp: manage sink power state if possible
  drm/i915/dp: consolidate AUX retry code
  drm/i915/dp: remove DPMS mode tracking from DP
  drm/i915/dp: try to read receiver capabilities 3 times when detecting
  drm/i915/dp: read more receiver capability bits on hotplug
  drm/i915/dp: use DP DPCD defines when looking at DPCD values
  drm/i915/dp: retry link status read 3 times on failure

Because struct rpcbind_args *map was declared static, if two
threads entered this method at the same time, the values
assigned to map could be sent two two differen tasks.
This could cause all sorts of problems, include use-after-free
and double-free of memory.

Fix this by removing the static declaration so that the map
pointer is on the stack.
Signed-off-by: Ben Greear <greearb@candelatech.com>
Cc: stable@kernel.org
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

...which is measured by the size and not the amount of space remaining.

Waiting upon size-8, did one of two things. In the common case with more
than 8 bytes available to write into the ring, it would return
immediately. Otherwise, it would timeout given the impossible condition
of waiting for more space than is available in the ring, leading to
warnings such as:

[drm:intel_cleanup_ring_buffer] *ERROR* failed to quiesce render ring
whilst cleaning up: -16
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Keith Packard <keithp@keithp.com>

This reverts commit a51f7a66.

We still have a few Ironlake and Sandybridge machines which fail when
RC6 is enabled. Better luck next release?
Signed-off-by: Keith Packard <keithp@keithp.com>

i915_driver_load adds a write-combining MTRR region for the GTT
aperture to improve memory speeds through the aperture. If
i915_driver_load fails after this, it would not have cleaned up the
MTRR. This shouldn't cause any problems, except for consuming an MTRR
register. Still, it's best to clean up completely in the failure path,
which is easily done by calling mtrr_del if the mtrr was successfully
allocated.

i915_driver_load calls i915_gem_load which register
i915_gem_inactive_shrink. If i915_driver_load fails after calling
i915_gem_load, the shrinker will be left registered. When called, it
will access freed memory and crash. The fix is to unregister the shrinker in the
failure path using code duplicated from i915_driver_unload.

i915_driver_load also has some incorrect gotos in the error cleanup
paths:

 * After failing to initialize the GTT (which cannot happen, btw,
   intel_gtt_get returns a fixed (non-NULL) value), it tries to
   free the uninitialized WC IO mapping. Fixed this by changing the
   target from out_iomapfree to out_rmmap
Signed-off-by: Keith Packard <keithp@keithp.com>
Tested-by: Lin Ming <ming.m.lin@intel.com>