A user reported a panic while running a balance.  What was happening was he was
relocating a block, which added the reference to the relocation tree.  Then
relocation would walk through the relocation tree and drop that reference and
free that block, and then it would walk down a snapshot which referenced the
same block and add another ref to the block.  The problem is this was all
happening in the same transaction, so the parent block was free'ed up when we
drop our reference which was immediately available for allocation, and then it
was used _again_ to add a reference for the same block from a different
snapshot.  This resulted in something like this in the delayed ref tree

add ref to 90234880, parent=2067398656, ref_root 1766, level 1
del ref to 90234880, parent=2067398656, ref_root 18446744073709551608, level 1
add ref to 90234880, parent=2067398656, ref_root 1767, level 1

as you can see the ref_root's don't match, because when we inc the ref we use
the header owner, which is the original tree the block belonged to, instead of
the data reloc tree.  Then when we remove the extent we use the reloc tree
objectid.  But none of this matters, since it is a shared reference which means
only the parent matters.  When the delayed ref stuff runs it adds all the
increments first, and then does all the drops, to make sure that we don't delete
the ref if we net a positive ref count.  But tree blocks aren't allowed to have
multiple refs from the same block, so this panics when it tries to add the
second ref.  We need the add and the drop to cancel each other out in memory so
we only do the final add.

So to fix this we need to adjust how the delayed refs are added to the tree.
Only the ref_root matters when it is a normal backref, and only the parent
matters when it is a shared backref.  So make our decision based on what ref
type we have.  This allows us to keep the ref_root in memory in case anybody
wants to use it for something else, and it allows the delayed refs to be merged
properly so we don't end up with this panic.

With this patch the users image no longer panics on mount, and it has a clean
fsck after a normal mount/umount cycle.  Thanks,

Cc: stable@vger.kernel.org
Reported-by: NRoman Mamedov <rm@romanrm.ru>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Testing my enospc log code I managed to abort a transaction during mount, which
put me into an infinite loop.  This is because of two things, first we don't
reset trans_no_join if we abort during transaction commit, which will force
anybody trying to start a transaction to just loop endlessly waiting for it to
be set to 0.  But this is still just a symptom, the second issue is we don't set
the fs state to error during errors on mount.  This is because we don't want to
do the flip read only thing during mount, but we still really want to set the fs
state to an error to keep us from even getting to the trans_no_join check.  So
fix both of these things, make sure to reset trans_no_join if we abort during a
commit, and make sure we set the fs state to error no matter if we're mounting
or not.  This should keep us from getting into this infinite loop again.
Thanks,
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Steps to reproduce:
	mkfs.btrfs <disk>
	mount <disk> <mnt>
	btrfs quota enable <mnt>
	btrfs sub create <mnt>/subv

	i=1
	while [ $i -le 10000 ]
	do
		dd if=/dev/zero of=<mnt>/subv/data_$i bs=1K count=1
		i=$(($i+1))
		if [ $i -eq 500 ]
		then
			btrfs quota disable $mnt
		fi
	done
	dmesg
Obviously, this warn_on() is unnecessary, and it will be easily triggered.
Just remove it.
Signed-off-by: NWang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

set_extent_bit()'s (u64 *failed_start) expects NULL not 0.
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

The subvolume ioctls block on the parent directory mutex that can be
held by other concurrent snapshot activity for a long time. Give the
user at least some chance to get out of this situation by allowing
to send a kill signal.
Signed-off-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Signed-off-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

The messages

  btrfs: unlinked 123 orphans
  btrfs: truncated 456 orphans

are not useful to regular users and raise questions whether there are
problems with the filesystem.
Signed-off-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

This mount option was a workaround when subvol= assumed path relative
to the default subvolume, not the toplevel one. This was fixed long time
ago and subvolrootid has no effect.
Signed-off-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

With more than one btrfs volume mounted, it can be very difficult to find
out which volume is hitting an error. btrfs_error() will print this, but
it is currently rigged as more of a fatal error handler, while many of
the printk()s are currently for debugging and yet-unhandled cases.

This patch just changes the functions where the device information is
already available. Some cases remain where the root or fs_info is not
passed to the function emitting the error.

This may introduce some confusion with volumes backed by multiple devices
emitting errors referring to the primary device in the set instead of the
one on which the error occurred.

Use btrfs_printk(fs_info, format, ...) rather than writing the device
string every time, and introduce macro wrappers ala XFS for brevity.
Since the function already cannot be used for continuations, print a
newline as part of the btrfs_printk() message rather than at each caller.
Signed-off-by: NSimon Kirby <sim@hostway.ca>
Reviewed-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

The Kconfig title does not make much sense after the cleanup of
CONFIG_EXPERIMENTAL option, align the wording with other filesystems.
Signed-off-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Each time pick one dead root from the list and let the caller know if
it's needed to continue. This should improve responsiveness during
umount and balance which at some point waits for cleaning all currently
queued dead roots.

A new dead root is added to the end of the list, so the snapshots
disappear in the order of deletion.

The snapshot cleaning work is now done only from the cleaner thread and the
others wake it if needed.
Signed-off-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Signed-off-by: NZhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Signed-off-by: NZhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Share the exactly same code of stopping workers.
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

We currently store the first key of the tree block inside the reference for the
tree block in the extent tree.  This takes up quite a bit of space.  Make a new
key type for metadata which holds the level as the offset and completely removes
storing the btrfs_tree_block_info inside the extent ref.  This reduces the size
from 51 bytes to 33 bytes per extent reference for each tree block.  In practice
this results in a 30-35% decrease in the size of our extent tree, which means we
COW less and can keep more of the extent tree in memory which makes our heavy
metadata operations go much faster.  This is not an automatic format change, you
must enable it at mkfs time or with btrfstune.  This patch deals with having
metadata stored as either the old format or the new format so it is easy to
convert.  Thanks,
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

free_root_pointers() has been introduced to cleanup all of tree roots,
so just use it instead.
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Reviewed-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Argument 'root' is no more used in btrfs_csum_data().
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

The transaction abort stacktrace is printed only once per module
lifetime, but we'd like to see it each time it happens per mounted
filesystem.  Introduce a fs_state flag that records it.

Tweak the messages around abort:
* add error number to the first abort
* print the exact negative errno from btrfs_decode_error
* clean up btrfs_decode_error and callers
* no dots at the end of the messages
Signed-off-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

Signed-off-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

We keep hitting bugs in the tree log replay because btrfs_remove_free_space
doesn't account for some corner case.  So add a bunch of tests to try and fully
test btrfs_remove_free_space since the only time it is called is during tree log
replay.  These tests all finish successfully, so as we find more of these bugs
we need to add to these tests to make sure we don't regress in fixing things.
I've hidden the tests behind a Kconfig option, but they take no time to run so
all btrfs developers should have this turned on all the time.  Thanks,
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

btrfs_abort_devices() is no more used.
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

dprintk() shouldn't access @ring after it's unmapped.
Signed-off-by: NZhao Hongjiang <zhaohongjiang@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This reverts commit 3a366e61.

Wanlong Gao reports that it causes a kernel panic on his machine several
minutes after boot. Reverting it removes the panic.

Jens says:
 "It's not quite clear why that is yet, so I think we should just revert
  the commit for 3.9 final (which I'm assuming is pretty close).

  The wifi is crap at the LSF hotel, so sending this email instead of
  queueing up a revert and pull request."
Reported-by: NWanlong Gao <gaowanlong@cn.fujitsu.com>
Requested-by: NJens Axboe <axboe@kernel.dk>
Cc: Tejun Heo <tj@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Change a u32 to loff_t hfsplus_file_truncate().
Signed-off-by: NVyacheslav Dubeyko <slava@dubeyko.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Hin-Tak Leung <htl10@users.sourceforge.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Documentation/filesystems/proc.txt says about coredump_filter bitmask,

  Note bit 0-4 doesn't effect any hugetlb memory. hugetlb memory are only
  effected by bit 5-6.

However current code can go into the subsequent flag checks of bit 0-4
for vma(VM_HUGETLB). So this patch inserts 'return' and makes it work
as written in the document.
Signed-off-by: NNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: NRik van Riel <riel@redhat.com>
Acked-by: NMichal Hocko <mhocko@suse.cz>
Reviewed-by: NHATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Acked-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
Cc: <stable@vger.kernel.org>	[3.7+]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently we fail to include any data on hugepages into coredump,
because VM_DONTDUMP is set on hugetlbfs's vma.  This behavior was
recently introduced by commit 314e51b9 ("mm: kill vma flag
VM_RESERVED and mm->reserved_vm counter").

This looks to me a serious regression, so let's fix it.
Signed-off-by: NNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: NKonstantin Khlebnikov <khlebnikov@openvz.org>
Acked-by: NMichal Hocko <mhocko@suse.cz>
Reviewed-by: NRik van Riel <riel@redhat.com>
Acked-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
Cc: <stable@vger.kernel.org>	[3.7+]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Revert commit 62a3ddef ("vfs: fix spinning prevention in prune_icache_sb").

This commit doesn't look right: since we are looking at the tail of the
list (sb->s_inode_lru.prev) if we want to skip an inode, we should put
it back at the head of the list instead of the tail, otherwise we will
keep spinning on it.

Discovered when investigating why prune_icache_sb came top in perf
reports of a swapping load.
Signed-off-by: NSuleiman Souhlal <suleiman@google.com>
Signed-off-by: NHugh Dickins <hughd@google.com>
Cc: stable@vger.kernel.org # v3.2+
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

While trying to track down a tree log replay bug I noticed that fsck was always
complaining about nbytes not being right for our fsynced file.  That is because
the new fsync stuff doesn't wait for ordered extents to complete, so the inodes
nbytes are not necessarily updated properly when we log it.  So to fix this we
need to set nbytes to whatever it is on the inode that is on disk, so when we
replay the extents we can just add the bytes that are being added as we replay
the extent.  This makes it work for the case that we have the wrong nbytes or
the case that we logged everything and nbytes is actually correct.  With this
I'm no longer getting nbytes errors out of btrfsck.

Cc: stable@vger.kernel.org
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>
Signed-off-by: NChris Mason <chris.mason@fusionio.com>

The smpboot threads rely on the park/unpark mechanism which binds per
cpu threads on a particular core. Though the functionality is racy:

CPU0	       	 	CPU1  	     	    CPU2
unpark(T)				    wake_up_process(T)
  clear(SHOULD_PARK)	T runs
			leave parkme() due to !SHOULD_PARK  
  bind_to(CPU2)		BUG_ON(wrong CPU)						    

We cannot let the tasks move themself to the target CPU as one of
those tasks is actually the migration thread itself, which requires
that it starts running on the target cpu right away.

The solution to this problem is to prevent wakeups in park mode which
are not from unpark(). That way we can guarantee that the association
of the task to the target cpu is working correctly.

Add a new task state (TASK_PARKED) which prevents other wakeups and
use this state explicitly for the unpark wakeup.

Peter noticed: Also, since the task state is visible to userspace and
all the parked tasks are still in the PID space, its a good hint in ps
and friends that these tasks aren't really there for the moment.

The migration thread has another related issue.

CPU0	      	     	 CPU1
Bring up CPU2
create_thread(T)
park(T)
 wait_for_completion()
			 parkme()
			 complete()
sched_set_stop_task()
			 schedule(TASK_PARKED)

The sched_set_stop_task() call is issued while the task is on the
runqueue of CPU1 and that confuses the hell out of the stop_task class
on that cpu. So we need the same synchronizaion before
sched_set_stop_task().
Reported-by: NDave Jones <davej@redhat.com>
Reported-and-tested-by: NDave Hansen <dave@sr71.net>
Reported-and-tested-by: NBorislav Petkov <bp@alien8.de>
Acked-by: NPeter Ziljstra <peterz@infradead.org>
Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: dhillf@gmail.com
Cc: Ingo Molnar <mingo@kernel.org>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1304091635430.21884@ionosSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Fixes a regression in cifs_parse_mount_options where a password
which begins with a delimitor is parsed incorrectly as being a blank
password.
Signed-off-by: NSachin Prabhu <sprabhu@redhat.com>
Acked-by: NJeff Layton <jlayton@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Make sure that we set the status to 0 on success. Missed in testing
because it never appears when doing multiple mounts to _different_
servers.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: <stable@vger.kernel.org> # 3.7.x: 7b1f1fd1: NFSv4/4.1: Fix bugs in nfs4[01]_walk_client_list

do_loopback calls lock_mount(path) and forget to unlock_mount
if clone_mnt or copy_mnt fails.

[   77.661566] ================================================
[   77.662939] [ BUG: lock held when returning to user space! ]
[   77.664104] 3.9.0-rc5+ #17 Not tainted
[   77.664982] ------------------------------------------------
[   77.666488] mount/514 is leaving the kernel with locks still held!
[   77.668027] 2 locks held by mount/514:
[   77.668817]  #0:  (&sb->s_type->i_mutex_key#7){+.+.+.}, at: [<ffffffff811cca22>] lock_mount+0x32/0xe0
[   77.671755]  #1:  (&namespace_sem){+++++.}, at: [<ffffffff811cca3a>] lock_mount+0x4a/0xe0
Signed-off-by: NAndrey Vagin <avagin@openvz.org>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

just what it sounds like; do that only to procfs subtrees you've
created - doing that to something shared with another driver is
not only antisocial, but might cause interesting races with
proc_create() and its ilk.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

Don't hold the NFSv4 sequence id while we check for open permission.
The call to ACCESS may block due to reboot recovery.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

It is unsafe to use list_for_each_entry_safe() here, because
when we drop the nn->nfs_client_lock, we pin the _current_ list
entry and ensure that it stays in the list, but we don't do the
same for the _next_ list entry. Use of list_for_each_entry() is
therefore the correct thing to do.

Also fix the refcounting in nfs41_walk_client_list().

Finally, ensure that the nfs_client has finished being initialised
and, in the case of NFSv4.1, that the session is set up.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Bryan Schumaker <bjschuma@netapp.com>
Cc: stable@vger.kernel.org [>= 3.7]

When we assign a new rpc_client to clp->cl_rpcclient, we need to destroy
the old one.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org [>=3.7]

This patch changes GFS2's discard issuing code so that it calls
function sb_issue_discard rather than blkdev_issue_discard. The
code was calling blkdev_issue_discard and specifying the correct
sector offset and sector size, but blkdev_issue_discard expects
these values to be in terms of 512 byte sectors, even if the native
sector size for the device is different. Calling sb_issue_discard
with the BLOCK size instead ensures the correct block-to-512b-sector
translation. I verified that "minlen" is specified in blocks, so
comparing it to a number of blocks is correct.
Signed-off-by: NBob Peterson <rpeterso@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

When withdraw occurs, we need to continue to allow unlocks of fcntl
locks to occur, however these will only be local, since the node has
withdrawn from the cluster. This prevents triggering a VFS level
bug trap due to locks remaining when a file is closed.
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

The error code in gfs2_rs_alloc() is set to ENOMEM when error
but never be used, instead, gfs2_rs_alloc() always return 0.
Fix to return 'error'.
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>