To avoid any possible races relating to the link count, we need to
recheck it under the inode's glock in all cases where it matters.
Also to ensure we never get any nasty surprises, this patch also
ensures that once the link count has hit zero it can never be
elevated by rereading in data from disk.

The only place we cannot provide a proper solution is in rename
in the case where we are removing a target inode and we discover
that the target inode has been already unlinked on another node.
The race window is very small, and we return EAGAIN in this case
to indicate what has happened. The proper solution would be to move
the lookup parts of rename from the vfs into library calls which
the fs could call directly, but that is potentially a very big job
and this fix should cover most cases for now.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

If the buffer is dirty or pinned, then as well as printing a
warning, we should also refuse to release the page in
question.

Currently this can occur if there is a race between mmap()ed
writers and O_DIRECT on the same file. With the addition of
->launder_page() in the future, we should be able to close
this gap.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

In the recent patches to update the AIL list code, I managed to
forget that the ail list lock got dropped, even though I
added a comment specifically to remind myself :(
Reported-by: Barry Marson <bmarson@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

The GFS2 fallocate code chooses a target size to for allocating chunks of
space.  Whenever it can't find any resource groups with enough space free, it
halves its target. Since this target is in bytes, eventually it will no longer
be a multiple of blksize.  As long as there is more space available in the
resource group than the target, this isn't a problem, since gfs2 will use the
actual space available, which is always a multiple of blksize.  However,
when gfs couldn't fallocate a bigger chunk than the target, it was using the
non-blksize aligned number. This caused a BUG in later code that required
blksize aligned offsets.  GFS2 now ensures that bytes is always a multiple of
blksize
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

Add a tracepoint for monitoring writeback of the AIL.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

This patch adds writeback_control to writing back the AIL
list. This means that we can then take advantage of the
information we get in ->write_inode() in order to set off
some pre-emptive writeback.

In addition, the AIL code is cleaned up a bit to make it
a bit simpler to understand.

There is still more which can usefully be done in this area,
but this is a good start at least.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

The GLF_LRU flag introduced in the previous patch can be
used to check if a glock is on the lru list when a new
holder is queued and if so remove it, without having first
to get the lru_lock.

The main purpose of this patch however is to optimise the
glocks left over when an inode at end of life is being
evicted. Previously such glocks were left with the GLF_LFLUSH
flag set, so that when reclaimed, each one required a log flush.
This patch resets the GLF_LFLUSH flag when there is nothing
left to flush thus preventing later log flushes as glocks are
reused or demoted.

In order to do this, we need to keep track of the number of
revokes which are outstanding, and also to clear the GLF_LFLUSH
bit after a log commit when only revokes have been processed.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

This adds support for two new flags. One keeps track of whether
the glock is on the LRU list or not. The other isn't really a
flag as such, but an indication of whether the glock has an
attached object or not. This indication is reported without
any locking, which is ok since we do not dereference the object
pointer but merely report whether it is NULL or not.

Also, this fixes one place where a tracepoint was missing, which
was at the point we remove deallocated blocks from the journal.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

This patch is designed to clean up GFS2's fsync
implementation and ensure that it really does get everything on
disk. Since ->write_inode() has been updated, we can call that
via the vfs library function sync_inode_metadata() and the only
remaining thing that has to be done is to ensure that we get
any revoke records in the log after the inode has been written back.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

The buffer_in_io() macro has been unused for some time,
so remove it.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

Rather than allowing the glocks to be scheduled for possible
reclaim as soon as they have exited the journal, this patch
delays their entry to the list until the glocks in question
are no longer in use.

This means that we will rely on the vm for writeback of all
dirty data and metadata from now on. When glocks are added
to the lru list they should be freeable much faster since all
the I/O required to free them should have already been completed.

This should lead to much better I/O patterns under low memory
conditions.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

In order to ensure that the mapping stats (and thus the bdi) are correctly
updated, this patch changes the AIL writeback to use the filemap_datawrite
function. This helps prevent stalls in balance_dirty_pages() due to
large amounts of dirty metadata when there is little or no dirty data
around.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

The GFS2 ->write_inode function should be more aggressive at writing
back to the filesystem. This adopts the XFS system of returning
-EAGAIN when the writeback has not been completely done. Also, we
now kick off in-place writeback when called with WB_SYNC_NONE,
but we only wait for it and flush the log when WB_SYNC_ALL is
requested.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

The previous patches made function gfs2_dir_exhash_dealloc do nothing
but call function foreach_leaf.  This patch simplifies the code by
moving the entire function foreach_leaf into gfs2_dir_exhash_dealloc.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

Function foreach_leaf used to look up the leaf block address and get
a buffer_head.  Then it would call leaf_dealloc which did the same
lookup.  This patch combines the two operations by making foreach_leaf
pass the leaf bh to leaf_dealloc.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

At the end of function gfs2_dir_exhash_dealloc, it was setting the dinode
type to "file" to prevent directory corruption in case of a crash.
It was doing so in its own journal transaction.  This patch makes the
change occur when the last call is make to leaf_dealloc, since it needs
to rewrite the directory dinode at that time anyway.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

Since foreach_leaf is only called with leaf_dealloc as its only possible
call function, we can simplify the code by making it call leaf_dealloc
directly.  This simplifies the code and eliminates the need for
leaf_call_t, the generic call method.  This is a first small step in
simplifying the directory leaf deallocation code.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

On rare occasions we encounter gfs2 problems where an
invalid bitmap state transition is attempted.  For example,
trying to "unlink" a free block.  In these cases, there
is really no useful information logged to debug the problem.
This patch adds more debug details that should allow us to
more closely examine the problem and possibly solve it.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

* 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6:
  drm/radeon/kms: pll tweaks for r7xx
  drm/nouveau: fix allocation of notifier object
  drm/nouveau: fix notifier memory corruption bug
  drm/nouveau: fix pinning of notifier block
  drm/nouveau: populate ttm_alloced with false, when it's not
  drm/nouveau: fix nv30 pcie boards
  drm/nouveau: split ramin_lock into two locks, one hardirq safe
  drm/radeon/kms: adjust evergreen display watermark setup
  drm/radeon/kms: add connectors even if i2c fails
  drm/radeon/kms: fix bad shift in atom iio table parser

Prefer min m to max p only on pre-r7xx asics.

Fixes:
https://bugs.freedesktop.org/show_bug.cgi?id=36197Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>

* 'nouveau/drm-nouveau-fixes' of /ssd/git/drm-nouveau-next:
  drm/nouveau: fix allocation of notifier object
  drm/nouveau: fix notifier memory corruption bug
  drm/nouveau: fix pinning of notifier block
  drm/nouveau: populate ttm_alloced with false, when it's not
  drm/nouveau: fix nv30 pcie boards
  drm/nouveau: split ramin_lock into two locks, one hardirq safe

Commit 73412c38 ("drm/nouveau: allocate
kernel's notifier object at end of block") intended to align end of
notifier block to page boundary, but start of block was miscalculated
to be off by -16 bytes. Fix it.
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

nouveau_bo_wr32 expects offset to be in words, but we pass value in bytes,
so after commit 73412c38 ("drm/nouveau: allocate
kernel's notifier object at end of block") we started to overwrite some memory
after notifier buffer object (previously m2mf_ntfy was always 0, so it didn't
matter it was a value in bytes).
Reported-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reported-by: Nigel Cunningham <lkml@nigelcunningham.com.au>
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Pekka Paalanen <pq@iki.fi>
Cc: stable@kernel.org    [2.6.38]
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

Problem introduced with commit 6ba9a683Reported-by: Bob Gleitsmann <rjgleits@bellsouth.net>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

Caught with kmemcheck on unrelated business.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

Wasn't aware they even existed, apparently they do!  They're actually
AGP chips with a bridge as far as I can tell, which puts them in the
same boat as nv40/nv45.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

Fixes a possible lock ordering reversal between context_switch_lock
and ramin_lock.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Francisco Jerez <currojerez@riseup.net>

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (51 commits)
  netfilter: ipset: Fix the order of listing of sets
  ip6_pol_route panic: Do not allow VLAN on loopback
  bnx2x: Fix port identification problem
  r8169: add Realtek as maintainer.
  ip: ip_options_compile() resilient to NULL skb route
  bna: fix memory leak during RX path cleanup
  bna: fix for clean fw re-initialization
  usbnet: Fix up 'FLAG_POINTTOPOINT' and 'FLAG_MULTI_PACKET' overlaps.
  iwlegacy: fix tx_power initialization
  Revert "tcp: disallow bind() to reuse addr/port"
  qlcnic: limit skb frags for non tso packet
  net: can: mscan: fix build breakage in mpc5xxx_can
  netfilter: ipset: set match and SET target fixes
  netfilter: ipset: bitmap:ip,mac type requires "src" for MAC
  sctp: fix oops while removed transport still using as retran path
  sctp: fix oops when updating retransmit path with DEBUG on
  net: Disable NETIF_F_TSO_ECN when TSO is disabled
  net: Disable all TSO features when SG is disabled
  sfc: Use rmb() to ensure reads occur in order
  ieee802154: Remove hacked CFLAGS in net/ieee802154/Makefile
  ...

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
  PCI: pci-label: Fix build failure when CONFIG_NLS is set to 'm' by allmodconfig

Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, gart: Make sure GART does not map physmem above 1TB
  x86, gart: Set DISTLBWALKPRB bit always
  x86, gart: Convert spaces to tabs in enable_gart_translation

Merge branch 'timer-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'timer-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  RTC: rtc-omap: Fix a leak of the IRQ during init failure
  posix clocks: Replace mutex with reader/writer semaphore

Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf, x86: Fix AMD family 15h FPU event constraints
  perf, x86: Fix pre-defined cache-misses event for AMD family 15h cpus
  perf evsel: Fix use of inherit
  perf hists browser: Fix seg fault when annotate null symbol

This reverts commit 35d9f510.

Quoth Jiri Slaby:
 "It fixes mmap when IOMMU is used on x86 only, but breaks architectures
  like ARM or PPC where virt_to_phys(dma_alloc_coherent) doesn't work.
  We need there dma_mmap_coherent or similar (the trickery what
  snd_pcm_default_mmap does but in some saner way).  But this cannot be
  done at this phase."
Requested-by: Jiri Slaby <jslaby@suse.cz>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-fixes:
  GFS2: filesystem hang caused by incorrect lock order
  GFS2: Don't try to deallocate unlinked inodes when mounted ro
  GFS2: directly write blocks past i_size
  GFS2: write_end error path fails to unlock transaction lock

A restoreable saving of sets requires that list:set type of sets
come last and the code part which should have taken into account
the ordering was broken. The patch fixes the listing order.
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Patrick McHardy <kaber@trash.net>

Depending on the unit mask settings some FPU events may be scheduled
only on cpu counter #3. This patch fixes this.
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@googlemail.com>
Link: http://lkml.kernel.org/r/1302913676-14352-3-git-send-email-robert.richter@amd.comSigned-off-by: Ingo Molnar <mingo@elte.hu>

With AMD cpu family 15h a unit mask was introduced for the Data Cache
Miss event (0x041/L1-dcache-load-misses). We need to enable bit 0
(first data cache miss or streaming store to a 64 B cache line) of
this mask to proper count data cache misses.

Now we set this bit for all families and models. In case a PMU does
not implement a unit mask for event 0x041 the bit is ignored.
Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1302913676-14352-2-git-send-email-robert.richter@amd.comSigned-off-by: Ingo Molnar <mingo@elte.hu>

* 'for-39-rc4' of git://codeaurora.org/quic/kernel/davidb/linux-msm:
  msm: timer: fix missing return value
  msm: Remove extraneous ffa device check