Workqueue can now handle high concurrency.  Use system_nrt_wq
instead of slow-work.

* Updated is_valid_oplock_break() to not call cifs_oplock_break_put()
  as advised by Steve French.  It might cause deadlock.  Instead,
  reference is increased after queueing succeeded and
  cifs_oplock_break() briefly grabs GlobalSMBSeslock before putting
  the cfile to make sure it doesn't put before the matching get is
  finished.

* Anton Blanchard reported that cifs conversion was using now gone
  system_single_wq.  Use system_nrt_wq which provides non-reentrance
  guarantee which is enough and much better.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NSteve French <sfrench@samba.org>
Cc: Anton Blanchard <anton@samba.org>

fscache no longer uses slow-work.  Drop references to it.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NDavid Howells <dhowells@redhat.com>

Make fscache operation to use only workqueue instead of combination of
workqueue and slow-work.  FSCACHE_OP_SLOW is dropped and
FSCACHE_OP_FAST is renamed to FSCACHE_OP_ASYNC and uses newly added
fscache_op_wq workqueue to execute op->processor().
fscache_operation_init_slow() is dropped and fscache_operation_init()
now takes @processor argument directly.

* Unbound workqueue is used.

* fscache_retrieval_work() is no longer necessary as OP_ASYNC now does
  the equivalent thing.

* sysctl fscache.operation_max_active added to control concurrency.
  The default value is nr_cpus clamped between 2 and
  WQ_UNBOUND_MAX_ACTIVE.

* debugfs support is dropped for now.  Tracing API based debug
  facility is planned to be added.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NDavid Howells <dhowells@redhat.com>

Make fscache object state transition callbacks use workqueue instead
of slow-work.  New dedicated unbound CPU workqueue fscache_object_wq
is created.  get/put callbacks are renamed and modified to take
@object and called directly from the enqueue wrapper and the work
function.  While at it, make all open coded instances of get/put to
use fscache_get/put_object().

* Unbound workqueue is used.

* work_busy() output is printed instead of slow-work flags in object
  debugging outputs.  They mean basically the same thing bit-for-bit.

* sysctl fscache.object_max_active added to control concurrency.  The
  default value is nr_cpus clamped between 4 and
  WQ_UNBOUND_MAX_ACTIVE.

* slow_work_sleep_till_thread_needed() is replaced with fscache
  private implementation fscache_object_sleep_till_congested() which
  waits on fscache_object_wq congestion.

* debugfs support is dropped for now.  Tracing API based debug
  facility is planned to be added.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NDavid Howells <dhowells@redhat.com>

The "file" argument for fsync is never null so we can remove this check.

What drew my attention here is that 7ea80859: "drop unused dentry
argument to ->fsync" introduced an unconditional dereference at the
start of the function and that generated a smatch warning.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

posix_acl_from_xattr() returns both ERR_PTRs and null, but it's OK to
pass null values to set_cached_acl()
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

If btrfs_ioctl_snap_destroy() deletes a snapshot but finishes
with end_transaction(), the cleaner kthread may come in and
drop the root in the same transaction.  If that's the case, the
root's refs still == 1 in the tree when btrfs_del_root() deletes
the item, because commit_fs_roots() hasn't updated it yet (that
happens during the commit).

This wasn't a problem before only because
btrfs_ioctl_snap_destroy() would commit the transaction before dropping
the dentry reference, so the dead root wouldn't get queued up until
after the fs root item was updated in the btree.

Since it is not an error to drop the root reference and the root in the
same transaction, just drop the BUG_ON() in btrfs_del_root().
Signed-off-by: NSage Weil <sage@newdream.net>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

when used Posix File System Test Suite(pjd-fstest) to test btrfs,
some cases about setfacl failed when noacl mount option used.
I simplified used commands in pjd-fstest, and the following steps
can reproduce it.
------------------------
# cd btrfs-part/
# mkdir aaa
# setfacl -m m::rw aaa    <- successed, but not expected by pjd-fstest.
------------------------
I checked ext3, a warning message occured, like as:
  setfacl: aaa/: Operation not supported
Certainly, it's expected by pjd-fstest.

So, i compared acl.c of btrfs and ext3. Based on that, a patch created.
Fortunately, it works.
Signed-off-by: NShi Weihua <shiwh@cn.fujitsu.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

On btrfs, do the following
------------------
# su user1
# cd btrfs-part/
# touch aaa
# getfacl aaa
  # file: aaa
  # owner: user1
  # group: user1
  user::rw-
  group::rw-
  other::r--
# su user2
# cd btrfs-part/
# setfacl -m u::rwx aaa
# getfacl aaa
  # file: aaa
  # owner: user1
  # group: user1
  user::rwx           <- successed to setfacl
  group::rw-
  other::r--
------------------
but we should prohibit it that user2 changing user1's acl.
In fact, on ext3 and other fs, a message occurs:
  setfacl: aaa: Operation not permitted

This patch fixed it.
Signed-off-by: NShi Weihua <shiwh@cn.fujitsu.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

btrfs_lookup_dir_item() can return either ERR_PTRs or null.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

btrfs_read_fs_root_no_name() returns ERR_PTRs on error so I added a
check for that.  It's not clear to me if it can also return NULL
pointers or not so I left the original NULL pointer check as is.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

This was added by a22285a6: "Btrfs: Integrate metadata reservation
with start_transaction".  If we goto out here then we skip all the
unwinding and there are locks still held etc.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

btrfs_iget() returns an ERR_PTR() on failure and not null.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

Unwind and return -ENOMEM if the allocation fails here.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

If btrfs_lookup_dir_item() fails, we should can just let the mount fail
with an error.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

Tree blocks can live in data block groups in FS converted from extN.
So it's easy to trigger the BUG_ON.
Signed-off-by: NYan Zheng <zheng.yan@oracle.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

Fix a potential null dereference in relocation.c
Signed-off-by: NYan Zheng <zheng.yan@oracle.com>
Acked-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

when we use remap_file_pages() to remap a file, remap_file_pages always return
error. It is because btrfs didn't set VM_CAN_NONLINEAR for vma.
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

refs can be used with uninitialized data if btrfs_lookup_extent_info()
fails on the first pass through the loop.  In the original code if that
happens then check_path_shared() probably returns 1, this patch
changes it to return 1 for safety.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

Seems that when btrfs_fallocate was converted to use the new ENOSPC stuff we
dropped passing the mode to the function that actually does the preallocation.
This breaks anybody who wants to use FALLOC_FL_KEEP_SIZE.  Thanks,
Signed-off-by: NJosef Bacik <josef@redhat.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

We cannot use the loop device which has been connected to a file in the btrf

The reproduce steps is following:
 # dd if=/dev/zero of=vdev0 bs=1M count=1024
 # losetup /dev/loop0 vdev0
 # mkfs.btrfs /dev/loop0
 ...
 failed to zero device start -5

The reason is that the btrfs don't implement either ->write_begin or ->write
the VFS API, so we fix it by setting ->write to do_sync_write().
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NChris Mason <chris.mason@oracle.com>

If we have enough memory to allocate a new cap release message, do so, so
that we can send a partial release message immediately.  This keeps us from
making the MDS wait when the cap release it needs is in a partially full
release message.

If we fail because of ENOMEM, oh well, they'll just have to wait a bit
longer.
Signed-off-by: NSage Weil <sage@newdream.net>

If we get an IMPORT that give us a cap, but we don't have the inode, queue
a release (and try to send it immediately) so that the MDS doesn't get
stuck waiting for us.
Signed-off-by: NSage Weil <sage@newdream.net>

Nothing is released here: the caps message is simply ignored in this case.
Signed-off-by: NSage Weil <sage@newdream.net>

bdi_seq is an atomic_long_t but we're using ATOMIC_INIT, which causes
 build failures on ia64. This patch fixes it to use ATOMIC_LONG_INIT.
Signed-off-by: NJeff Mahoney <jeffm@suse.com>
Signed-off-by: NSage Weil <sage@newdream.net>

As it stands this check compares the number of pages to the page size.
This makes no sense and makes the fcntl fail in almost any sane case.

Fix it by checking if nr_pages is not zero (it can become zero only if
arg is too big and round_pipe_size() overflows).
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>

pipe_set_size() needs to copy pipe bufs from the old circular buffer
to the new.

The current code gets this wrong in multiple ways, resulting in oops.

Test program is available here:
  http://www.kernel.org/pub/linux/kernel/people/mszeredi/piperesize/Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>

We do the same BUG_ON() just a line later when calling into
__bd_abort_claiming().
Reported-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>

I don't like the subtle multi-context code in bd_claim (ie.  detects where it
has been called based on bd_claiming). It seems clearer to just require a new
function to finish a 2-part claim.

Also improve commentary in bd_start_claiming as to how it should
be used.
Signed-off-by: NNick Piggin <npiggin@suse.de>
Acked-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>

bd_start_claiming has an unbalanced module_put introduced in 6b4517a7.
Signed-off-by: NNick Piggin <npiggin@suse.de>
Acked-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>

Now that the background flush code has been fixed, we shouldn't need to
silently multiply the wbc->nr_to_write to get good writeback. Remove
that code.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This reportedly causes a lockdep warning on nfsd shutdown.  That looks
like a false positive to me, but there's no reason why this needs the
state lock anyway.
Reported-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

jffs2 didn't update the ctime of the file when its permission was changed.

Steps to reproduce:
 # touch aaa
 # stat -c %Z aaa
 1275289822
 # setfacl -m  'u::x,g::x,o::x' aaa
 # stat -c %Z aaa
 1275289822                         <- unchanged

But, according to the spec of the ctime, jffs2 must update it.

Port of ext3 patch by Miao Xie <miaox@cn.fujitsu.com>.
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

A few functions were still modifying i_flags in a racy manner.
Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

The data chunk is mmaped with 'len' which remains unchanged, so use that
when unmapping in the error path rather than trying to recalculate (and
incorrectly so) the value used originally.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Acked-by: NDavid McCullough <davidm@snapgear.com>
Acked-by: NGreg Ungerer <gerg@uclinux.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The stack and data have different alignment requirements, so don't force
them to wear the same shoe.  Increase the data alignment to match that
which the elf2flt linker script has always been using: 0x20 bytes.  Not
only does this bring the kernel loader in line with the toolchain, but it
also fixes a swath of gcc tests which try to force larger alignment values
but randomly fail when the FLAT loader fails to deliver.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: David Woodhouse <David.Woodhouse@intel.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: NDavid McCullough <davidm@snapgear.com>
Acked-by: NGreg Ungerer <gerg@uclinux.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Tested-by: NMichal Simek <monstr@monstr.eu>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Jie Zhang <jie@codesourcery.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

A call to access_ok is missing a compat_ptr conversion.  Introduced with
b8373363 "compat: factor out
compat_rw_copy_check_uvector from compat_do_readv_writev"

fs/compat.c: In function 'compat_rw_copy_check_uvector':
fs/compat.c:629: warning: passing argument 1 of '__access_ok' makes pointer from integer without a cast
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: NJeff Moyer <jmoyer@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove a left over fail label.
Signed-off-by: NAndrew Hendry <andrew.hendry@gmail.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

mtime and ctime should be changed only if the file size has actually
changed. Patches changing ext2 and tmpfs from vmtruncate to new truncate
sequence has caused regressions where they always update timestamps.

There is some strange cases in POSIX where truncate(2) must not update
times unless the size has acutally changed, see 6e656be8.

This area is all still rather buggy in different ways in a lot of
filesystems and needs a cleanup and audit (ideally the vfs will provide
a simple attribute or call to direct all filesystems exactly which
attributes to change). But coming up with the best solution will take a
while and is not appropriate for rc anyway.

So fix recent regression for now.
Signed-off-by: NNick Piggin <npiggin@suse.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

sysfs and configfs setattr functions have error cases after the generic inode's
attributes have been changed. Fix consistency by changing the generic inode
attributes only when it is guaranteed to succeed.
Signed-off-by: NNick Piggin <npiggin@suse.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>