Seeing that just about every destructor got that INIT_LIST_HEAD() copied into
it, there is no point whatsoever keeping this INIT_LIST_HEAD in inode_init_once();
the cost of taking it into inode_init_always() will be negligible for pipes
and sockets and negative for everything else.  Not to mention the removal of
boilerplate code from ->destroy_inode() instances...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

new helper (wrapper around mnt_drop_write()) to be used in pair with
mnt_want_write_file().
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

The label 'out_bdi' should be followed by bdi_destroy() instead of
fput() which should be after the 'out_fput' label.

If bdi_setup_and_register() fails then jump to the 'out_fput' label
instead of the 'out_bdi' one.

If fget(data.info_fd) fails then jump to the previously fixed 'out_bdi'
label to call bdi_destroy() otherwise the bdi object will not be
destroyed.

Compile tested only.
Signed-off-by: NDjalal Harouni <tixxdz@opendz.org>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Replace remaining direct i_nlink updates with a new set_nlink()
updater function.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Tested-by: NToshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Btrfs needs to be able to control how filemap_write_and_wait_range() is called
in fsync to make it less of a painful operation, so push down taking i_mutex and
the calling of filemap_write_and_wait() down into the ->fsync() handlers.  Some
file systems can drop taking the i_mutex altogether it seems, like ext3 and
ocfs2.  For correctness sake I just pushed everything down in all cases to make
sure that we keep the current behavior the same for everybody, and then each
individual fs maintainer can make up their mind about what to do from there.
Thanks,
Acked-by: NJan Kara <jack@suse.cz>
Signed-off-by: NJosef Bacik <josef@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

ncpfs does not handle references to unlinked directories (or so it would
seem given the ncp_rmdir check).  Since it is also possible to rename over
an empty directory, perform the same check here.

CC: Petr Vandrovec <petr@vandrovec.name>
CC: linux-kernel@vger.kernel.org
Signed-off-by: NSage Weil <sage@newdream.net>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

ncpfs returns EBUSY if there are any references to the directory.  The
dentry_unhash call only unhashes the dentry if there are no references.

CC: Petr Vandrovec <petr@vandrovec.name>
CC: linux-kernel@vger.kernel.org
Signed-off-by: NSage Weil <sage@newdream.net>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Two new stats in per-memcg memory.stat which tracks the number of page
faults and number of major page faults.

  "pgfault"
  "pgmajfault"

They are different from "pgpgin"/"pgpgout" stat which count number of
pages charged/discharged to the cgroup and have no meaning of reading/
writing page to disk.

It is valuable to track the two stats for both measuring application's
performance as well as the efficiency of the kernel page reclaim path.
Counting pagefaults per process is useful, but we also need the aggregated
value since processes are monitored and controlled in cgroup basis in
memcg.

Functional test: check the total number of pgfault/pgmajfault of all
memcgs and compare with global vmstat value:

  $ cat /proc/vmstat | grep fault
  pgfault 1070751
  pgmajfault 553

  $ cat /dev/cgroup/memory.stat | grep fault
  pgfault 1071138
  pgmajfault 553
  total_pgfault 1071142
  total_pgmajfault 553

  $ cat /dev/cgroup/A/memory.stat | grep fault
  pgfault 199
  pgmajfault 0
  total_pgfault 199
  total_pgmajfault 0

Performance test: run page fault test(pft) wit 16 thread on faulting in
15G anon pages in 16G container.  There is no regression noticed on the
"flt/cpu/s"

Sample output from pft:

  TAG pft:anon-sys-default:
    Gb  Thr CLine   User     System     Wall    flt/cpu/s fault/wsec
    15   16   1     0.67s   233.41s    14.76s   16798.546 266356.260

  +-------------------------------------------------------------------------+
      N           Min           Max        Median           Avg        Stddev
  x  10     16682.962     17344.027     16913.524     16928.812      166.5362
  +  10     16695.568     16923.896     16820.604     16824.652     84.816568
  No difference proven at 95.0% confidence

[akpm@linux-foundation.org: fix build]
[hughd@google.com: shmem fix]
Signed-off-by: NYing Han <yinghan@google.com>
Acked-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: NMinchan Kim <minchan.kim@gmail.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Acked-by: NBalbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: NHugh Dickins <hughd@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Only a few file systems need this.  Start by pushing it down into each
rename method (except gfs2 and xfs) so that it can be dealt with on a
per-fs basis.
Acked-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NSage Weil <sage@newdream.net>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Only a few file systems need this.  Start by pushing it down into each
fs rmdir method (except gfs2 and xfs) so it can be dealt with on a per-fs
basis.

This does not change behavior for any in-tree file systems.
Acked-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NSage Weil <sage@newdream.net>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

We get this spurious warning:

  fs/ncpfs/inode.c: In function 'ncp_fill_super':
  fs/ncpfs/inode.c:451: warning: 'data.mounted_vol[1u]' may be used uninitialized in this function
  fs/ncpfs/inode.c:451: warning: 'data.mounted_vol[2u]' may be used uninitialized in this function
  fs/ncpfs/inode.c:451: warning: 'data.mounted_vol[3u]' may be used uninitialized in this function
  ...

It's notabug, but we can easily fix it with a memset().
Reported-by: NHarry Wei <jiaweiwei.xiyou@gmail.com>
Cc: Petr Vandrovec <petr@vandrovec.name>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fixes generated by 'codespell' and manually reviewed.
Signed-off-by: NLucas De Marchi <lucas.demarchi@profusion.mobi>

Replace EXTRA_CFLAGS with ccflags-y. And change ntfs-objs to ntfs-y
for cleaner conditional inclusion.
Signed-off-by: Nmatt mooney <mfm@muteddisk.com>
Acked-by: NWANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: NMichal Marek <mmarek@suse.cz>

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

merge dentry_operations for root and non-root
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Require filesystems be aware of .d_revalidate being called in rcu-walk
mode (nd->flags & LOOKUP_RCU). For now do a simple push down, returning
-ECHILD from all implementations.
Signed-off-by: NNick Piggin <npiggin@kernel.dk>

Reduce some branches and memory accesses in dcache lookup by adding dentry
flags to indicate common d_ops are set, rather than having to check them.
This saves a pointer memory access (dentry->d_op) in common path lookup
situations, and saves another pointer load and branch in cases where we
have d_op but not the particular operation.

Patched with:

git grep -E '[.>]([[:space:]])*d_op([[:space:]])*=' | xargs sed -e 's/\([^\t ]*\)->d_op = \(.*\);/d_set_d_op(\1, \2);/' -e 's/\([^\t ]*\)\.d_op = \(.*\);/d_set_d_op(\&\1, \2);/' -i
Signed-off-by: NNick Piggin <npiggin@kernel.dk>

RCU free the struct inode. This will allow:

- Subsequent store-free path walking patch. The inode must be consulted for
  permissions when walking, so an RCU inode reference is a must.
- sb_inode_list_lock to be moved inside i_lock because sb list walkers who want
  to take i_lock no longer need to take sb_inode_list_lock to walk the list in
  the first place. This will simplify and optimize locking.
- Could remove some nested trylock loops in dcache code
- Could potentially simplify things a bit in VM land. Do not need to take the
  page lock to follow page->mapping.

The downsides of this is the performance cost of using RCU. In a simple
creat/unlink microbenchmark, performance drops by about 10% due to inability to
reuse cache-hot slab objects. As iterations increase and RCU freeing starts
kicking over, this increases to about 20%.

In cases where inode lifetimes are longer (ie. many inodes may be allocated
during the average life span of a single inode), a lot of this cache reuse is
not applicable, so the regression caused by this patch is smaller.

The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU,
however this adds some complexity to list walking and store-free path walking,
so I prefer to implement this at a later date, if it is shown to be a win in
real situations. I haven't found a regression in any non-micro benchmark so I
doubt it will be a problem.
Signed-off-by: NNick Piggin <npiggin@kernel.dk>

dget_locked was a shortcut to avoid the lazy lru manipulation when we already
held dcache_lock (lru manipulation was relatively cheap at that point).
However, how that the lru lock is an innermost one, we never hold it at any
caller, so the lock cost can now be avoided. We already have well working lazy
dcache LRU, so it should be fine to defer LRU manipulations to scan time.
Signed-off-by: NNick Piggin <npiggin@kernel.dk>

dcache_lock no longer protects anything. remove it.
Signed-off-by: NNick Piggin <npiggin@kernel.dk>

Protect d_subdirs and d_child with d_lock, except in filesystems that aren't
using dcache_lock for these anyway (eg. using i_mutex).

Note: if we change the locking rule in future so that ->d_child protection is
provided only with ->d_parent->d_lock, it may allow us to reduce some locking.
But it would be an exception to an otherwise regular locking scheme, so we'd
have to see some good results. Probably not worthwhile.
Signed-off-by: NNick Piggin <npiggin@kernel.dk>

Change d_hash so it may be called from lock-free RCU lookups. See similar
patch for d_compare for details.

For in-tree filesystems, this is just a mechanical change.
Signed-off-by: NNick Piggin <npiggin@kernel.dk>

Change d_compare so it may be called from lock-free RCU lookups. This
does put significant restrictions on what may be done from the callback,
however there don't seem to have been any problems with in-tree fses.
If some strange use case pops up that _really_ cannot cope with the
rcu-walk rules, we can just add new rcu-unaware callbacks, which would
cause name lookup to drop out of rcu-walk mode.

For in-tree filesystems, this is just a mechanical change.
Signed-off-by: NNick Piggin <npiggin@kernel.dk>

smpfs and ncpfs want to update a live dentry name in-place. Rather than
have them open code the locking, provide a documented dcache API.
Signed-off-by: NNick Piggin <npiggin@kernel.dk>

Change d_delete from a dentry deletion notification to a dentry caching
advise, more like ->drop_inode. Require it to be constant and idempotent,
and not take d_lock. This is how all existing filesystems use the callback
anyway.

This makes fine grained dentry locking of dput and dentry lru scanning
much simpler.
Signed-off-by: NNick Piggin <npiggin@kernel.dk>

flush_scheduled_work() is deprecated and scheduled to be removed.
Directly flush the used works on stop instead.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Petr Vandrovec <petr@vandrovec.name>

The big kernel lock has been removed from all these files at some point,
leaving only the #include.

Remove this too as a cleanup.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

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

Otherwise partially updated pointers could be seen if
pointer update is not atomic.
Signed-off-by: NPetr Vandrovec <petr@vandrovec.name>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>

Dozen of changes in ncpfs to provide some locking other than BKL.

In readdir cache unlock and mark complete first page as last operation,
so it can be used for synchronization, as code intended.

When updating dentry name on case insensitive filesystems do at least
some basic locking...

Hold i_mutex when updating inode fields.

Push some ncp_conn_is_valid down to ncp_request.  Connection can become
invalid at any moment, and fewer error code paths to test the better.

Use i_size_{read,write} to modify file size.

Set inode's backing_dev_info as ncpfs has its own special bdi.

In ioctl unbreak ioctls invoked on filesystem mounted 'ro' - tests are
for inode writeable or owner match, but were turned to filesystem
writeable and inode writeable or owner match.  Also collect all permission
checks in single place.

Add some locking, and remove comments saying that it would be cool to
add some locks to the code.

Constify some pointers.
Signed-off-by: NPetr Vandrovec <petr@vandrovec.name>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>

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

Replace inode_setattr with opencoded variants of it in all callers.  This
moves the remaining call to vmtruncate into the filesystem methods where it
can be replaced with the proper truncate sequence.

In a few cases it was obvious that we would never end up calling vmtruncate
so it was left out in the opencoded variant:

 spufs: explicitly checks for ATTR_SIZE earlier
 btrfs,hugetlbfs,logfs,dlmfs: explicitly clears ATTR_SIZE earlier
 ufs: contains an opencoded simple_seattr + truncate that sets the filesize just above

In addition to that ncpfs called inode_setattr with handcrafted iattrs,
which allowed to trim down the opencoded variant.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Remove duplicated #include('s) in
  fs/ncpfs/ioctl.c
Signed-off-by: NHuang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>

Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Do not use the fallback default_llseek() if the readdir operation of the
filesystem still uses the big kernel lock.

Since llseek() modifies
file->f_pos of the directory directly it may need locking to not confuse
readdir which usually uses file->f_pos directly as well

Since the special characteristics of the BKL (unlocked on schedule) are
not necessary in this case, the inode mutex can be used for locking as
provided by generic_file_llseek().  This is only possible since all
filesystems, except reiserfs, either use a directory as a flat file or
with disk address offsets.  Reiserfs on the other hand uses a 32bit hash
off the filename as the offset so generic_file_llseek() can get used as
well since the hash is always smaller than sb->s_maxbytes (= (512 << 32) -
blocksize).
Signed-off-by: NJan Blunck <jblunck@suse.de>
Acked-by: NJan Kara <jack@suse.cz>
Acked-by: NAnders Larsen <al@alarsen.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Convert ncp_ioctl to an unlocked_ioctl and push down the bkl into it.
Signed-off-by: NJohn Kacur <jkacur@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Petr Vandrovec <vandrove@vc.cvut.cz>
Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>

This ensures that dirty data gets flushed properly.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: NTejun Heo <tj@kernel.org>
Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

That is "success", "unknown", "through", "performance", "[re|un]mapping"
, "access", "default", "reasonable", "[con]currently", "temperature"
, "channel", "[un]used", "application", "example","hierarchy", "therefore"
, "[over|under]flow", "contiguous", "threshold", "enough" and others.
Signed-off-by: NAndré Goddard Rosa <andre.goddard@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>