The tree logging code allows individual files or directories to be logged
without including operations on other files and directories in the FS.
It tries to commit the minimal set of changes to disk in order to
fsync the single file or directory that was sent to fsync or O_SYNC.

The tree logging code was allowing files and directories to be unlinked
if they were part of a rename operation where only one directory
in the rename was in the fsync log.  This patch adds a few new rules
to the tree logging.

1) on rename or unlink, if the inode being unlinked isn't in the fsync
log, we must force a full commit before doing an fsync of the directory
where the unlink was done.  The commit isn't done during the unlink,
but it is forced the next time we try to log the parent directory.

Solution: record transid of last unlink/rename per directory when the
directory wasn't already logged.  For renames this is only done when
renaming to a different directory.

mkdir foo/some_dir
normal commit
rename foo/some_dir foo2/some_dir
mkdir foo/some_dir
fsync foo/some_dir/some_file

The fsync above will unlink the original some_dir without recording
it in its new location (foo2).  After a crash, some_dir will be gone
unless the fsync of some_file forces a full commit

2) we must log any new names for any file or dir that is in the fsync
log.  This way we make sure not to lose files that are unlinked during
the same transaction.

2a) we must log any new names for any file or dir during rename
when the directory they are being removed from was logged.

2a is actually the more important variant.  Without the extra logging
a crash might unlink the old name without recreating the new one

3) after a crash, we must go through any directories with a link count
of zero and redo the rm -rf

mkdir f1/foo
normal commit
rm -rf f1/foo
fsync(f1)

The directory f1 was fully removed from the FS, but fsync was never
called on f1, only its parent dir.  After a crash the rm -rf must
be replayed.  This must be able to recurse down the entire
directory tree.  The inode link count fixup code takes care of the
ugly details.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

During log replay, inodes are copied from the log to the main filesystem
btrees.  Sometimes they have a zero link count in the log but they actually
gain links during the replay or have some in the main btree.

This patch updates the link count to be at least one after copying the
inode out of the log.  This makes sure the inode is deleted during an
iput while the rest of the replay code is still working on it.

The log replay has fixup code to make sure that link counts are correct
at the end of the replay, so we could use any non-zero number here and
it would work fine.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

The delayed reference mechanism is responsible for all updates to the
extent allocation trees, including those updates created while processing
the delayed references.

This commit tries to limit the amount of work that gets created during
the final run of delayed refs before a commit.  It avoids cowing new blocks
unless it is required to finish the commit, and so it avoids new allocations
that were not really required.

The goal is to avoid infinite loops where we are always making more work
on the final run of delayed refs.  Over the long term we'll make a
special log for the last delayed ref updates as well.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

This reads in blocks in the checksum btree before starting the
transaction in btrfs_finish_ordered_io.  It makes it much more likely
we'll be able to do operations inside the transaction without
needing any btree reads, which limits transaction latencies overall.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

btrfs_mark_buffer dirty would set dirty bits in the extent_io tree
for the buffers it was dirtying.  This may require a kmalloc and it
was not atomic.  So, anyone who called btrfs_mark_buffer_dirty had to
set any btree locks they were holding to blocking first.

This commit changes dirty tracking for extent buffers to just use a flag
in the extent buffer.  Now that we have one and only one extent buffer
per page, this can be safely done without losing dirty bits along the way.

This also introduces a path->leave_spinning flag that callers of
btrfs_search_slot can use to indicate they will properly deal with a
path returned where all the locks are spinning instead of blocking.

Many of the btree search callers now expect spinning paths,
resulting in better btree concurrency overall.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

Commits are fairly expensive, and so btrfs has code to sit around for a while
during the commit and let new writers come in.

But, while we're sitting there, new delayed refs might be added, and those
can be expensive to process as well.  Unless the transaction is very very
young, it makes sense to go ahead and let the commit finish without hanging
around.

The commit grow loop isn't as important as it used to be, the fsync logging
code handles most performance critical syncs now.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

This reduces contention on the extent buffer spin locks by testing for a
blocking lock before trying to take the spinlock.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

The fs/btrfs/inode.c code to run delayed allocation during writout
needed some stack usage optimization.  This is the first pass, it does
the check for compression earlier on, which allows us to do the common
(no compression) case higher up in the call chain.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

To avoid deadlocks and reduce latencies during some critical operations, some
transaction writers are allowed to jump into the running transaction and make
it run a little longer, while others sit around and wait for the commit to
finish.

This is a bit unfair, especially when the callers that jump in do a bunch
of IO that makes all the others procs on the box wait.  This commit
reduces the stalls this produces by pre-reading file extent pointers
during btrfs_finish_ordered_io before the transaction is joined.

It also tunes the drop_snapshot code to politely wait for transactions
that have started writing out their delayed refs to finish.  This avoids
new delayed refs being flooded into the queue while we're trying to
close off the transaction.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

The delayed reference queue maintains pending operations that need to
be done to the extent allocation tree.  These are processed by
finding records in the tree that are not currently being processed one at
a time.

This is slow because it uses lots of time searching through the rbtree
and because it creates lock contention on the extent allocation tree
when lots of different procs are running delayed refs at the same time.

This commit changes things to grab a cluster of refs for processing,
using a cursor into the rbtree as the starting point of the next search.
This way we walk smoothly through the rbtree.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

When extents are freed, it is likely that we've removed the last
delayed reference update for the extent.  This checks the delayed
ref tree when things are freed, and if no ref updates area left it
immediately processes the delayed ref.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

Many of the tree balancing functions follow the same pattern.

1) cow a block
2) do something to the result

This commit breaks them up into two functions so the variables and
code required for part two don't suck down stack during part one.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

The extent allocation tree maintains a reference count and full
back reference information for every extent allocated in the
filesystem.  For subvolume and snapshot trees, every time
a block goes through COW, the new copy of the block adds a reference
on every block it points to.

If a btree node points to 150 leaves, then the COW code needs to go
and add backrefs on 150 different extents, which might be spread all
over the extent allocation tree.

These updates currently happen during btrfs_cow_block, and most COWs
happen during btrfs_search_slot.  btrfs_search_slot has locks held
on both the parent and the node we are COWing, and so we really want
to avoid IO during the COW if we can.

This commit adds an rbtree of pending reference count updates and extent
allocations.  The tree is ordered by byte number of the extent and byte number
of the parent for the back reference.  The tree allows us to:

1) Modify back references in something close to disk order, reducing seeks
2) Significantly reduce the number of modifications made as block pointers
are balanced around
3) Do all of the extent insertion and back reference modifications outside
of the performance critical btrfs_search_slot code.

#3 has the added benefit of greatly reducing the btrfs stack footprint.
The extent allocation tree modifications are done without the deep
(and somewhat recursive) call chains used in the past.

These delayed back reference updates must be done before the transaction
commits, and so the rbtree is tied to the transaction.  Throttling is
implemented to help keep the queue of backrefs at a reasonable size.

Since there was a similar mechanism in place for the extent tree
extents, that is removed and replaced by the delayed reference tree.

Yan Zheng <yan.zheng@oracle.com> helped review and fixup this code.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

In order to avoid doing expensive extent management with tree locks held,
btrfs_search_slot will preallocate tree blocks for use by COW without
any tree locks held.

A later commit moves all of the extent allocation work for COW into
a delayed update mechanism, and this preallocation will no longer be
required.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

Update all previous incarnations of my email address to the correct one.
Signed-off-by: NGertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If ecryptfs_encrypted_view or ecryptfs_xattr_metadata were being
specified as mount options, a NULL pointer dereference of crypt_stat
was possible during lookup.

This patch moves the crypt_stat assignment into
ecryptfs_lookup_and_interpose_lower(), ensuring that crypt_stat
will not be NULL before we attempt to dereference it.

Thanks to Dan Carpenter and his static analysis tool, smatch, for
finding this bug.
Signed-off-by: NTyler Hicks <tyhicks@linux.vnet.ibm.com>
Acked-by: NDustin Kirkland <kirkland@canonical.com>
Cc: Dan Carpenter <error27@gmail.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When allocating the memory used to store the eCryptfs header contents, a
single, zeroed page was being allocated with get_zeroed_page().
However, the size of an eCryptfs header is either PAGE_CACHE_SIZE or
ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE (8192), whichever is larger, and is
stored in the file's private_data->crypt_stat->num_header_bytes_at_front
field.

ecryptfs_write_metadata_to_contents() was using
num_header_bytes_at_front to decide how many bytes should be written to
the lower filesystem for the file header.  Unfortunately, at least 8K
was being written from the page, despite the chance of the single,
zeroed page being smaller than 8K.  This resulted in random areas of
kernel memory being written between the 0x1000 and 0x1FFF bytes offsets
in the eCryptfs file headers if PAGE_SIZE was 4K.

This patch allocates a variable number of pages, calculated with
num_header_bytes_at_front, and passes the number of allocated pages
along to ecryptfs_write_metadata_to_contents().

Thanks to Florian Streibelt for reporting the data leak and working with
me to find the problem.  2.6.28 is the only kernel release with this
vulnerability.  Corresponds to CVE-2009-0787
Signed-off-by: NTyler Hicks <tyhicks@linux.vnet.ibm.com>
Acked-by: NDustin Kirkland <kirkland@canonical.com>
Reviewed-by: NEric Sandeen <sandeen@redhat.com>
Reviewed-by: NEugene Teo <eugeneteo@kernel.sg>
Cc: Greg KH <greg@kroah.com>
Cc: dann frazier <dannf@dannf.org>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: Florian Streibelt <florian@f-streibelt.de>
Cc: stable@kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The libaio test harness turned up a problem whereby lookup_ioctx on a
bogus io context was returning the 1 valid io context from the list
(harness/cases/3.p).

Because of that, an extra put_iocontext was done, and when the process
exited, it hit a BUG_ON in the put_iocontext macro called from exit_aio
(since we expect a users count of 1 and instead get 0).

The problem was introduced by "aio: make the lookup_ioctx() lockless"
(commit abf137dd).

Thanks to Zach for pointing out that hlist_for_each_entry_rcu will not
return with a NULL tpos at the end of the loop, even if the entry was
not found.
Signed-off-by: NJeff Moyer <jmoyer@redhat.com>
Acked-by: NZach Brown <zach.brown@oracle.com>
Acked-by: NJens Axboe <jens.axboe@oracle.com>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove a source of fput() call from inside IRQ context.  Myself, like Eric,
wasn't able to reproduce an fput() call from IRQ context, but Jeff said he was
able to, with the attached test program.  Independently from this, the bug is
conceptually there, so we might be better off fixing it.  This patch adds an
optimization similar to the one we already do on ->ki_filp, on ->ki_eventfd.
Playing with ->f_count directly is not pretty in general, but the alternative
here would be to add a brand new delayed fput() infrastructure, that I'm not
sure is worth it.
Signed-off-by: NDavide Libenzi <davidel@xmailserver.org>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: NJeff Moyer <jmoyer@redhat.com>
Cc: Zach Brown <zach.brown@oracle.com>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Nick Piggin noticed this (very unlikely) race between setting a page
dirty and creating the buffers for it - we need to hold the mapping
private_lock until we've set the page dirty bit in order to make sure
that create_empty_buffers() might not build up a set of buffers without
the dirty bits set when the page is dirty.

I doubt anybody has ever hit this race (and it didn't solve the issue
Nick was looking at), but as Nick says: "Still, it does appear to solve
a real race, which we should close."
Acked-by: NNick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Although this operation is unsupported by our implementation
we still need to provide an encode routine for it to
merely encode its (error) status back in the compound reply.

Thanks for Bill Baker at sun.com for testing with the Sun
OpenSolaris' client, finding, and reporting this bug at
Connectathon 2009.

This bug was introduced in 2.6.27
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Cc: stable@kernel.org
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Commit ee6f779b ("filp->f_pos not
correctly updated in proc_task_readdir") changed the proc code to use
filp->f_pos directly, rather than through a temporary variable.  In the
process, that caused the operations to be done on the full 64 bits, even
though the offset is never that big.

That's all fine and dandy per se, but for some unfathomable reason gcc
generates absolutely horrid code when using 64-bit values in switch()
statements.  To the point of actually calling out to gcc helper
functions like __cmpdi2 rather than just doing the trivial comparisons
directly the way gcc does for normal compares.  At which point we get
link failures, because we really don't want to support that kind of
crazy code.

Fix this by just casting the f_pos value to "unsigned long", which
is plenty big enough for /proc, and avoids the gcc code generation issue.
Reported-by: NAlexey Dobriyan <adobriyan@gmail.com>
Cc: Zhang Le <r0bertz@gentoo.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This is for Red Hat bug 490026: EXT4 panic, list corruption in
ext4_mb_new_inode_pa

ext4_lock_group(sb, group) is supposed to protect this list for
each group, and a common code flow to remove an album is like
this:

    ext4_get_group_no_and_offset(sb, pa->pa_pstart, &grp, NULL);
    ext4_lock_group(sb, grp);
    list_del(&pa->pa_group_list);
    ext4_unlock_group(sb, grp);

so it's critical that we get the right group number back for
this prealloc context, to lock the right group (the one 
associated with this pa) and prevent concurrent list manipulation.

however, ext4_mb_put_pa() passes in (pa->pa_pstart - 1) with a 
comment, "-1 is to protect from crossing allocation group".

This makes sense for the group_pa, where pa_pstart is advanced
by the length which has been used (in ext4_mb_release_context()),
and when the entire length has been used, pa_pstart has been
advanced to the first block of the next group.

However, for inode_pa, pa_pstart is never advanced; it's just
set once to the first block in the group and not moved after
that.  So in this case, if we subtract one in ext4_mb_put_pa(),
we are actually locking the *previous* group, and opening the
race with the other threads which do not subtract off the extra
block.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

filp->f_pos only get updated at the end of the function. Thus d_off of those
dirents who are in the middle will be 0, and this will cause a problem in
glibc's readdir implementation, specifically endless loop. Because when overflow
occurs, f_pos will be set to next dirent to read, however it will be 0, unless
the next one is the last one. So it will start over again and again.

There is a sample program in man 2 gendents. This is the output of the program
running on a multithread program's task dir before this patch is applied:

  $ ./a.out /proc/3807/task
  --------------- nread=128 ---------------
  i-node#  file type  d_reclen  d_off   d_name
    506442  directory    16          1  .
    506441  directory    16          0  ..
    506443  directory    16          0  3807
    506444  directory    16          0  3809
    506445  directory    16          0  3812
    506446  directory    16          0  3861
    506447  directory    16          0  3862
    506448  directory    16          8  3863

This is the output after this patch is applied

  $ ./a.out /proc/3807/task
  --------------- nread=128 ---------------
  i-node#  file type  d_reclen  d_off   d_name
    506442  directory    16          1  .
    506441  directory    16          2  ..
    506443  directory    16          3  3807
    506444  directory    16          4  3809
    506445  directory    16          5  3812
    506446  directory    16          6  3861
    506447  directory    16          7  3862
    506448  directory    16          8  3863
Signed-off-by: NZhang Le <r0bertz@gentoo.org>
Acked-by: NAl Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If bio_integrity_clone() fails, bio_clone() returns NULL without freeing
the newly allocated bio.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Stricter gfp_mask might be required for clone allocation.
For example, request-based dm may clone bio in interrupt context
so it has to use GFP_ATOMIC.
Signed-off-by: NKiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: NJun'ichi Nomura <j-nomura@ce.jp.nec.com>
Acked-by: NMartin K. Petersen <martin.petersen@oracle.com>
Cc: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

eCryptfs has file encryption keys (FEK), file encryption key encryption
keys (FEKEK), and filename encryption keys (FNEK).  The per-file FEK is
encrypted with one or more FEKEKs and stored in the header of the
encrypted file.  I noticed that the FEK is also being encrypted by the
FNEK.  This is a problem if a user wants to use a different FNEK than
their FEKEK, as their file contents will still be accessible with the
FNEK.

This is a minimalistic patch which prevents the FNEKs signatures from
being copied to the inode signatures list.  Ultimately, it keeps the FEK
from being encrypted with a FNEK.
Signed-off-by: NTyler Hicks <tyhicks@linux.vnet.ibm.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Acked-by: NDustin Kirkland <kirkland@canonical.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When a ramfs nommu mapping is expanded, contiguous pages are allocated
and added to the pagecache.  The caller's reference is then passed on
by moving whole pagevecs to the file lru list.

If the page cache adding fails, make sure that the error path also
moves the pagevec contents which might still contain up to PAGEVEC_SIZE
successfully added pages, of which we would leak references otherwise.
Signed-off-by: NJohannes Weiner <hannes@cmpxchg.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Enrik Berkhan <Enrik.Berkhan@ge.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The pages attached to a ramfs inode's pagecache by truncation from nothing
- as done by SYSV SHM for example - may get discarded under memory
pressure.

The problem is that the pages are not marked dirty.  Anything that creates
data in an MMU-based ramfs will cause the pages holding that data will
cause the set_page_dirty() aop to be called.

For the NOMMU-based mmap, set_page_dirty() may be called by write(), but
it won't be called by page-writing faults on writable mmaps, and it isn't
called by ramfs_nommu_expand_for_mapping() when a file is being truncated
from nothing to allocate a contiguous run.

The solution is to mark the pages dirty at the point of allocation by the
truncation code.
Signed-off-by: NEnrik Berkhan <Enrik.Berkhan@ge.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Thiemo Nagel reported that:

# dd if=/dev/zero of=image.ext4 bs=1M count=2
# mkfs.ext4 -v -F -b 1024 -m 0 -g 512 -G 4 -I 128 -N 1 \
  -O large_file,dir_index,flex_bg,extent,sparse_super image.ext4
# mount -o loop image.ext4 mnt/
# dd if=/dev/zero of=mnt/file

oopsed, with a BUG_ON in ext4_mb_normalize_request because
size == EXT4_BLOCKS_PER_GROUP

It appears to me (esp. after talking to Andreas) that the BUG_ON
is bogus; a request of exactly EXT4_BLOCKS_PER_GROUP should
be allowed, though larger sizes do indicate a problem.

Fix that an another (apparently rare) codepath with a similar check.
Reported-by: NThiemo Nagel <thiemo.nagel@ph.tum.de>
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

A long time ago, xs->base is allocated a 4K size and all the contents
in the bucket are copied to the it. Now we use ocfs2_xattr_bucket to
abstract xattr bucket and xs->base is initialized to the start of the
bu_bhs[0]. So xs->base + offset will overflow when the value root is
stored outside the first block.

Then why we can survive the xattr test by now? It is because we always
read the bucket contiguously now and kernel mm allocate continguous
memory for us. We are lucky, but we should fix it. So just get the
right value root as other callers do.
Signed-off-by: NTao Ma <tao.ma@oracle.com>
Acked-by: NJoel Becker <joel.becker@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

We need to use le32_to_cpu to test rec->e_cpos in
ocfs2_dinode_insert_check.
Signed-off-by: NTao Ma <tao.ma@oracle.com>
Acked-by: NJoel Becker <joel.becker@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

Replace max_inline_data with max_inline_data_with_xattr
to ensure it correct when xattr inlined.
Signed-off-by: NTiger Yang <tiger.yang@oracle.com>
Acked-by: NJoel Becker <joel.becker@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

If this is a new directory with inline data, we choose to
reserve the entire inline area for directory contents and
force an external xattr block.
Signed-off-by: NTiger Yang <tiger.yang@oracle.com>
Acked-by: NJoel Becker <joel.becker@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

There was a report of a data corruption
http://lkml.org/lkml/2008/11/14/121.  There is a script included to
reproduce the problem.

During testing, I encountered a number of strange things with ext3, so I
tried ext2 to attempt to reduce complexity of the problem.  I found that
fsstress would quickly hang in wait_on_inode, waiting for I_LOCK to be
cleared, even though instrumentation showed that unlock_new_inode had
already been called for that inode.  This points to memory scribble, or
synchronisation problme.

i_state of I_NEW inodes is not protected by inode_lock because other
processes are not supposed to touch them until I_LOCK (and I_NEW) is
cleared.  Adding WARN_ON(inode->i_state & I_NEW) to sites where we modify
i_state revealed that generic_sync_sb_inodes is picking up new inodes from
the inode lists and passing them to __writeback_single_inode without
waiting for I_NEW.  Subsequently modifying i_state causes corruption.  In
my case it would look like this:

CPU0                            CPU1
unlock_new_inode()              __sync_single_inode()
 reg <- inode->i_state
 reg -> reg & ~(I_LOCK|I_NEW)   reg <- inode->i_state
 reg -> inode->i_state          reg -> reg | I_SYNC
                                reg -> inode->i_state

Non-atomic RMW on CPU1 overwrites CPU0 store and sets I_LOCK|I_NEW again.

Fix for this is rather than wait for I_NEW inodes, just skip over them:
inodes concurrently being created are not subject to data integrity
operations, and should not significantly contribute to dirty memory
either.

After this change, I'm unable to reproduce any of the added warnings or
hangs after ~1hour of running.  Previously, the new warnings would start
immediately and hang would happen in under 5 minutes.

I'm also testing on ext3 now, and so far no problems there either.  I
don't know whether this fixes the problem reported above, but it fixes a
real problem for me.

Cc: "Jorge Boncompte [DTI2]" <jorge@dti2.net>
Reported-by: NAdrian Hunter <ext-adrian.hunter@nokia.com>
Cc: Jan Kara <jack@suse.cz>
Cc: <stable@kernel.org>
Signed-off-by: NNick Piggin <npiggin@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In sget(), destroy_super(s) is called with s->s_umount held, which makes
lockdep unhappy.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Menage <menage@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If the second fasync_helper() fails, pipe_rdwr_fasync() returns the error
but leaves the file on ->fasync_readers.

This was always wrong, but since 233e70f4
"saner FASYNC handling on file close" we have the new problem.  Because in
this case setfl() doesn't set FASYNC bit, __fput() will not do
->fasync(0), and we leak fasync_struct with ->fa_file pointing to the
freed file.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Stephen Rothwell reports:

Today's linux-next build (powerpc ppc64_defconfig) failed like this:

fs/built-in.o: In function `.nfs_get_client':
client.c:(.text+0x115010): undefined reference to `.__ipv6_addr_type'

Fix by moving the IPV6 specific parts of commit
d7371c41 ("Bug 11061, NFS mounts dropped")
into the '#ifdef IPV6..." section.

Also fix up a couple of formatting issues.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This is a short-term warning, and even printk_ratelimit() can result
in too much noise in system logs.  So only print it once as a warning.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

The corrupted filesystem patch added a check against zlib trying to
output too much data in the presence of data corruption.  This check
triggered if zlib_inflate asked to be called again (Z_OK) with
avail_out == 0 and no more output buffers available.  This check proves
to be rather dumb, as it incorrectly catches the case where zlib has
generated all the output, but there are still input bytes to be processed.

This patch does a number of things.  It removes the original check and
replaces it with code to not move to the next output buffer if there
are no more output buffers available, relying on zlib to error if it
wants an extra output buffer in the case of data corruption.  It
also replaces the Z_NO_FLUSH flag with the more correct Z_SYNC_FLUSH
flag, and makes the error messages more understandable to
non-technical users.
Signed-off-by: NPhillip Lougher <phillip@lougher.demon.co.uk>
Reported-by: NStefan Lippers-Hollmann <s.L-H@gmx.de>