So far i_mutex was ranking above dqonoff_mutex and i_mutex on quota files
was special and ranking below dqonoff_mutex (and several other locks).
However there's no real need for i_mutex on quota files to be special.
IO on quota files is serialized by dqio_mutex anyway so we don't need to
take i_mutex when writing to quota files. Other places where we take i_mutex
on quota file can accomodate standard i_mutex lock ranking, we only need
to change the lock ranking to be dqonoff_mutex > i_mutex which is a matter
of changing documentation because there's no place which would enforce
ordering in the other direction.
Signed-off-by: NJan Kara <jack@suse.cz>

Signed-off-by: NJan Kara <jack@suse.cz>

We don't need i_mutex in ext2_quota_write() because writes to quota file
are serialized by dqio_mutex anyway. Changes to quota files outside of quota
code are forbidded and enforced by NOATIME and IMMUTABLE bits.
Signed-off-by: NJan Kara <jack@suse.cz>

We don't need i_mutex in reiserfs_quota_write() because writes to quota file
are serialized by dqio_mutex anyway. Changes to quota files outside of quota
code are forbidded and enforced by NOATIME and IMMUTABLE bits.
Signed-off-by: NJan Kara <jack@suse.cz>

We don't need i_mutex in ext4_quota_write() because writes to quota file
are serialized by dqio_mutex anyway. Changes to quota files outside of quota
code are forbidded and enforced by NOATIME and IMMUTABLE bits.
Signed-off-by: NJan Kara <jack@suse.cz>

We don't need i_mutex in ext3_quota_write() because writes to quota file
are serialized by dqio_mutex anyway. Changes to quota files outside of quota
code are forbidded and enforced by NOATIME and IMMUTABLE bits.
Signed-off-by: NJan Kara <jack@suse.cz>

When CONFIG_QUOTA_DEBUG is enabled we call inode_get_rsv_space() from
add_dquot_ref() while holding i_lock. But inode_get_rsv_space() is trying
to get i_lock as well resulting in double lock.

Fix the problem by moving inode_get_rsv_space() call out of i_lock.
Reported-and-analyzed-by: NJie Liu <jeff.liu@oracle.com>
Signed-off-by: NJan Kara <jack@suse.cz>

If journal superblock is written only in disk's caches and other transaction
starts reusing space of the transaction cleaned from the log, it can happen
blocks of a new transaction reach the disk before journal superblock. When
power failure happens in such case, subsequent journal replay would still try
to replay the old transaction but some of it's blocks may be already
overwritten by the new transaction. For this reason we must use WRITE_FUA when
updating log tail and we must first write new log tail to disk and update
in-memory information only after that.
Signed-off-by: NJan Kara <jack@suse.cz>

There are some log tail updates that are not protected by j_checkpoint_mutex.
Some of these are harmless because they happen during startup or shutdown but
updates in journal_commit_transaction() and journal_flush() can really race
with other log tail updates (e.g. someone doing journal_flush() with someone
running cleanup_journal_tail()). So protect all log tail updates with
j_checkpoint_mutex.
Signed-off-by: NJan Kara <jack@suse.cz>

There are three case of updating journal superblock. In the first case, we want
to mark journal as empty (setting s_sequence to 0), in the second case we want
to update log tail, in the third case we want to update s_errno. Split these
cases into separate functions. It makes the code slightly more straightforward
and later patches will make the distinction even more important.
Signed-off-by: NJan Kara <jack@suse.cz>

Jan Kara removed 'sb->s_dirt' VFS flag references, so we do not need to
register the ext2 'ext2_write_super()' method in the VFS superblock operations,
because 'sb->s_dirt' won't be ever set to 1 and VFS won't ever call
'->write_super()' anyway. Thus, remove the method.

Tested using xfstests.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NJan Kara <jack@suse.cz>

Places which modify superblock feature / state fields mark the superblock
buffer dirty so it is written out by flusher thread. Thus there's no need to
set s_dirt there.

The only other fields changing in the superblock are the numbers of free
blocks, free inodes and s_wtime. There's no real need to write (or even
compute) these periodically. Free blocks / inodes counters are recomputed on
every mount from group counters anyway and value of s_wtime is only
informational and imprecise anyway. So it should be enough to write these
opportunistically on mount, remount, umount, and sync_fs times.
Signed-off-by: NJan Kara <jack@suse.cz>

Currently on unmount if we are mounted R/W, we first write the superblock to
the media if it is dirty, and then write it again, which is not optimal. This
patch makes ext2 write the superblock on unmount less times.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NJan Kara <jack@suse.cz>

Commit 00eacd66 ("ext3: make ext3 mount default to barrier=1") changed
the default barrier mount option for ext3.  The documentation needs to
be updated, so this patch does that.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NStefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: NJan Kara <jack@suse.cz>

max_debt, involved variables and calculations
are no longer needed, clean them up.
Signed-off-by: NAkira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: NJan Kara <jack@suse.cz>

Currently we write out all journal buffers in WRITE_SYNC mode. This improves
performance for fsync heavy workloads but hinders performance when writes
are mostly asynchronous, most noticably it slows down readers and users
complain about slow desktop response etc.

So submit writes as asynchronous in the normal case and only submit writes as
WRITE_SYNC if we detect someone is waiting for current transaction commit.

I've gathered some numbers to back this change. The first is the read latency
test. It measures time to read 1 MB after several seconds of sleeping in
presence of streaming writes.

Top 10 times (out of 90) in us:
Before		After
2131586		697473
1709932		557487
1564598		535642
1480462		347573
1478579		323153
1408496		222181
1388960		181273
1329565		181070
1252486		172832
1223265		172278

Average:
619377		82180

So the improvement in both maximum and average latency is massive.

I've measured fsync throughput by:
fs_mark -n 100 -t 1 -s 16384 -d /mnt/fsync/ -S 1 -L 4

in presence of streaming reader. The numbers (fsyncs/s) are:
Before		After
9.9		6.3
6.8		6.0
6.3		6.2
5.8		6.1

So fsync performance seems unharmed by this change.
Signed-off-by: NJan Kara <jack@suse.cz>

This fixes builds where CONFIG_AUDIT is not defined and
CONFIG_SECURITY_SMACK=y.

This got introduced by the stack-usage reducation commit 48c62af6
("LSM: shrink the common_audit_data data union").
Signed-off-by: NKees Cook <keescook@chromium.org>
Acked-by: NEric Paris <eparis@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Pull dmaengine fixes from Dan Williams:

1/ regression fix for Xen as it now trips over a broken assumption
   about the dma address size on 32-bit builds

2/ new quirk for netdma to ignore dma channels that cannot meet
   netdma alignment requirements

3/ fixes for two long standing issues in ioatdma (ring size overflow)
   and iop-adma (potential stack corruption)

* tag 'dmaengine-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/dmaengine:
  netdma: adding alignment check for NETDMA ops
  ioatdma: DMA copy alignment needed to address IOAT DMA silicon errata
  ioat: ring size variables need to be 32bit to avoid overflow
  iop-adma: Corrected array overflow in RAID6 Xscale(R) test.
  ioat: fix size of 'completion' for Xen

Pull sparc fixes from David Miller:

1) Build fix for LEON, from Sam Ravnborg.

2) Make the sparc side changes that go along with the infrastructure to
   retry faults when blocking on a disk transfer.  From Kautuk Consul.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc32,leon: fix leon build
  sparc/mm/fault_32.c: Port OOM changes to do_sparc_fault
  sparc/mm/fault_64.c: Port OOM changes to do_sparc64_fault

Pull a regulator build fix from Mark Brown:
 "Fix a build warning in the anatop driver for 3.4

  This is a trivial rename to stop the build system complaining that
  we're referencing things we shouldn't be."

* tag 'regulator-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
  regulator: anatop: fix 'anatop_regulator' name collision

Pull UML fixes from Richard Weinberger.

* 'for-3.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
  um: uml_setup_stubs': warning: unused variable 'pages'
  um: Use asm-generic/switch_to.h
  um: Disintegrate asm/system.h
  um: switch cow_user.h to htobe{32,64}/betoh{32,64}
  um: several x86 hw-dependent crypto modules won't build on uml
  um: fix linker script generation

Don't call i2c_enable on resume because it causes a spurious
interrupt.
Signed-off-by: NKristen Carlson Accardi <kristen@linux.intel.com>
Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit f02e8a65 ("module: Sort exported symbols") sorts symbols
placing each of them in its own elf section.  This sorting and merging
into the canonical sections are done by the linker.

Unfortunately modpost to generate Module.symvers file parses vmlinux.o
(which is not linked yet) and all modules object files (which aren't
linked yet).  These aren't sanitized by the linker yet.  That breaks
modpost that can't detect license properly for modules.

This patch makes modpost aware of the new exported symbols structure.

[ This above is a slightly corrected version of the explanation of the
  problem, copied from commit 62a26356 ("modpost: Fix modpost's
  license checking V3").  That commit fixed the problem for module
  object files, but not for vmlinux.o.  This patch fixes modpost for
  vmlinux.o. ]
Signed-off-by: NFrank Rowand <frank.rowand@am.sony.com>
Signed-off-by: NAlessio Igor Bogani <abogani@kernel.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The task handoff notifier leaks task_struct since it never gets freed
after the callback returns NOTIFY_OK, which means it is responsible for
doing so.

It turns out the lowmemorykiller actually doesn't need this notifier at
all.  It's used to prevent unnecessary killing by waiting for a thread
to exit as a result of lowmem_shrink(), however, it's possible to do
this in the same way the kernel oom killer works by setting TIF_MEMDIE
and avoid killing if we're still waiting for it to exit.

The kernel oom killer will already automatically set TIF_MEMDIE for
threads that are attempting to allocate memory that have a fatal signal.
The thread selected by lowmem_shrink() will have such a signal after the
lowmemorykiller sends it a SIGKILL, so this won't result in an
unnecessary use of memory reserves for the thread to exit.

This has the added benefit that we don't have to rely on
CONFIG_PROFILING to prevent needlessly killing tasks.
Reported-by: NWerner Landgraf <w.landgraf@ru.ru>
Cc: stable@vger.kernel.org
Signed-off-by: NDavid Rientjes <rientjes@google.com>
Acked-by: NColin Cross <ccross@android.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix the following gcc complain
arch/um/kernel/skas/mmu.c: In function 'uml_setup_stubs':
arch/um/kernel/skas/mmu.c:106:16: warning: unused variable 'pages' [-Wunused-variable]
Signed-Signed-off-by: NBoaz Harrosh <bharrosh@panasas.com>
Signed-off-by: NRichard Weinberger <richard@nod.at>

Signed-off-by: NRichard Weinberger <richard@nod.at>

Signed-off-by: NRichard Weinberger <richard@nod.at>
Reported-by: NToralf Förster <toralf.foerster@gmx.de>
CC: dhowells@redhat.com

... rather than open-coding the 64bit versions.  endian.h has those guys.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NRichard Weinberger <richard@nod.at>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

while we can't just use -U$(SUBARCH), we still need to kill idiotic define
(implicit -Di386=1), both for SUBARCH=i386 and SUBARCH=x86/CONFIG_64BIT=n
builds.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Pull two more small regmap fixes from Mark Brown:
 - Now we have users for it that aren't running Android it turns out
   that regcache_sync_region() is much more useful to drivers if it's
   exported for use by modules.  Who knew?
 - Make sure we don't divide by zero when doing debugfs dumps of
   rbtrees, not visible up until now because everything was providing at
   least some cache on startup.

* tag 'regmap-3.4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
  regmap: prevent division by zero in rbtree_show
  regmap: Export regcache_sync_region()

Pull a few KVM fixes from Avi Kivity:
 "A bunch of powerpc KVM fixes, a guest and a host RCU fix (unrelated),
  and a small build fix."

* 'kvm-updates/3.4' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: Resolve RCU vs. async page fault problem
  KVM: VMX: vmx_set_cr0 expects kvm->srcu locked
  KVM: PMU: Fix integer constant is too large warning in kvm_pmu_set_msr()
  KVM: PPC: Book3S: PR: Fix preemption
  KVM: PPC: Save/Restore CR over vcpu_run
  KVM: PPC: Book3S HV: Save and restore CR in __kvmppc_vcore_entry
  KVM: PPC: Book3S HV: Fix kvm_alloc_linear in case where no linears exist
  KVM: PPC: Book3S: Compile fix for ppc32 in HIOR access code

Pull SuperH fixes from Paul Mundt.

* tag 'sh-for-linus' of git://github.com/pmundt/linux-sh:
  sh: fix clock-sh7757 for the latest sh_mobile_sdhi driver
  serial: sh-sci: use serial_port_in/out vs sci_in/out.
  sh: vsyscall: Fix up .eh_frame generation.
  sh: dma: Fix up device attribute mismatch from sysdev fallout.
  sh: dwarf unwinder depends on SHcompact.
  sh: fix up fallout from system.h disintegration.

Pull security layer fixlet from James Morris.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  sysctl: fix write access to dmesg_restrict/kptr_restrict

Pull ACPI & Power Management patches from Len Brown:
 "Two fixes for cpuidle merge-window changes, plus a URL fix in
  MAINTAINERS"

* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux:
  MAINTAINERS: Update git url for ACPI
  cpuidle: Fix panic in CPU off-lining with no idle driver
  ACPI processor: Use safe_halt() rather than halt() in acpi_idle_play_dead()

Pull target fixes from Nicholas Bellinger:
 "Pull two tcm_fc fabric related fixes for -rc2:

  Note that both have been CC'ed to stable, and patch #1 is the
  important one that addresses a memory corruption bug related to FC
  exchange timeouts + command abort.

  Thanks again to MDR for tracking down this issue!"

* '3.4-rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
  tcm_fc: Do not free tpg structure during wq allocation failure
  tcm_fc: Add abort flag for gracefully handling exchange timeout

Avoid freeing a registered tpg structure if an alloc_workqueue call
fails.  This fixes a bug where the failure was leaking memory associated
with se_portal_group setup during the original core_tpg_register() call.
Signed-off-by: NMark Rustad <mark.d.rustad@intel.com>
Acked-by: NKiran Patil <Kiran.patil@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Add abort flag and use it to terminate processing when an exchange
is timed out or is reset. The abort flag is used in place of the
transport_generic_free_cmd function call in the reset and timeout
cases, because calling that function in that context would free
memory that was in use. The aborted flag allows the lifetime to
be managed in a more normal way, while truncating the processing.

This change eliminates a source of memory corruption which
manifested in a variety of ugly ways.

(nab: Drop unused struct fc_exch *ep in ft_recv_seq)
Signed-off-by: NMark Rustad <mark.d.rustad@intel.com>
Acked-by: NKiran Patil <Kiran.patil@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>