Commit Graph

605 Commits

Author SHA1 Message Date
Josef Bacik
779880ef35 Btrfs: fix how we discard outstanding ordered extents on abort
When we abort we've been just free'ing up all the ordered extents and
hoping for the best.  This results in lots of warnings from various places,
warnings from btrfs_destroy_inode() because it's ENOSPC accounting isn't
fixed.  It will also screw up lots of pages who have been set private but
never get cleared because the ordered extents are never allowed to be
submitted.  This patch fixes those warnings.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20 12:59:28 -05:00
Josef Bacik
eb12db690c Btrfs: fix freeing delayed ref head while still holding its mutex
I hit this error when reproducing a bug that would end in a transaction
abort.  We take the delayed ref head's mutex to keep anybody from processing
it while we're destroying it, but we fail to drop the mutex before we carry
on and free the damned thing.  Fix this by doing the remove logic for the
head ourselves and unlock the mutex, that way we can avoid use after free's
or hung tasks waiting on that mutex to come back so they know the delayed
ref completed.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20 12:59:27 -05:00
Eric Sandeen
d1d3cd27a3 btrfs: list_entry can't return NULL
No need to test the result, we can't get a
null pointer from list_entry()

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20 12:59:15 -05:00
Miao Xie
87533c4751 Btrfs: use bit operation for ->fs_state
There is no lock to protect fs_info->fs_state, it will introduce
some problems, such as the value may be covered by the other task
when several tasks modify it. For example:
	Task0 - CPU0		Task1 - CPU1
	mov %fs_state rax
	or $0x1 rax
				mov %fs_state rax
				or $0x2 rax
	mov rax %fs_state
				mov rax %fs_state
The expected value is 3, but in fact, it is 2.

Though this problem doesn't happen now (because there is only one
flag currently), the code is error prone, if we add other flags,
the above problem will happen to a certainty.

Now we use bit operation for it to fix the above problem.
In this way, we can make the code more robust and be easy to
add new flags.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20 12:59:09 -05:00
Miao Xie
de98ced9e7 Btrfs: use seqlock to protect fs_info->avail_{data, metadata, system}_alloc_bits
There is no lock to protect
  fs_info->avail_{data, metadata, system}_alloc_bits,
it may introduce some problem, such as the wrong profile
information, so we add a seqlock to protect them.

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20 12:59:08 -05:00
Miao Xie
df0af1a57f Btrfs: use the inode own lock to protect its delalloc_bytes
We need not use a global lock to protect the delalloc_bytes of the
inode, just use its own lock. In this way, we can reduce the lock
contention and ->delalloc_lock will just protect delalloc inode
list.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20 12:59:06 -05:00
Miao Xie
963d678b0f Btrfs: use percpu counter for fs_info->delalloc_bytes
fs_info->delalloc_bytes is accessed very frequently, so use percpu
counter instead of the u64 variant for it to reduce the lock
contention.

This patch also fixed the problem that we access the variant
without the lock protection.At worst, we would not flush the
delalloc inodes, and just return ENOSPC error when we still have
some free space in the fs.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20 12:59:05 -05:00
Miao Xie
e2d845211e Btrfs: use percpu counter for dirty metadata count
->dirty_metadata_bytes is accessed very frequently, so use percpu
counter instead of the u64 variant to reduce the contention of
the lock.

This patch also fixed the problem that we access it without
lock protection in __btrfs_btree_balance_dirty(), which may
cause we skip the dirty pages flush.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20 12:59:04 -05:00
Liu Bo
a1897fddd2 Btrfs: record first logical byte in memory
This'd save us a rbtree search which may become expensive in large filesystem.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20 09:37:18 -05:00
Josef Bacik
2ab28f322f Btrfs: wait on ordered extents at the last possible moment
Since we don't actually copy the extent information from the source tree in
the fast case we don't need to wait for ordered io to be completed in order
to fsync, we just need to wait for the io to be completed.  So when we're
logging our file just attach all of the ordered extents to the log, and then
when the log syncs just wait for IO_DONE on the ordered extents and then
write the super.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20 09:37:04 -05:00
Miao Xie
4eee4fa4f8 Btrfs: use wrapper page_offset
Use wrapper page_offset to get byte-offset into filesystem object for page.

Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20 09:36:43 -05:00
Miao Xie
78a6184a3f Btrfs: use slabs for delayed reference allocation
The delayed reference allocation is in the fast path of the IO, so use slabs
to improve the speed of the allocation.

And besides that, it can do check for leaked objects when the module is removed.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
2013-02-20 09:36:34 -05:00
Josef Bacik
ed7b63eb8a Btrfs: only clear dirty on the buffer if it is marked as dirty
No reason to set the path blocking or loop through all of the pages if the
extent buffer isn't actually marked dirty.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:25 -05:00
Josef Bacik
bb146eb265 Btrfs: move checks in set_page_dirty under DEBUG
This is a high traffic function, let's try and do as little as possible
during normal operations shall we?

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:25 -05:00
Anand Jain
5f3ab90a72 Btrfs: rename root_times_lock to root_item_lock
Originally root_times_lock was introduced as part of send/receive
code however newly developed patch to label the subvol reused
the same lock, so renaming it for a meaningful name.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:21 -05:00
Miao Xie
26176e7c2a Btrfs: restructure btrfs_run_defrag_inodes()
This patch restructure btrfs_run_defrag_inodes() and make the code of the auto
defragment more readable.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:12 -05:00
Stefan Behrens
8dabb7420f Btrfs: change core code of btrfs to support the device replace operations
This commit contains all the essential changes to the core code
of Btrfs for support of the device replace procedure.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12 17:15:42 -05:00
Stefan Behrens
618919236b Btrfs: handle errors from btrfs_map_bio() everywhere
With the addition of the device replace procedure, it is possible
for btrfs_map_bio(READ) to report an error. This happens when the
specific mirror is requested which is located on the target disk,
and the copy operation has not yet copied this block. Hence the
block cannot be read and this error state is indicated by
returning EIO.
Some background information follows now. A new mirror is added
while the device replace procedure is running.
btrfs_get_num_copies() returns one more, and
btrfs_map_bio(GET_READ_MIRROR) adds one more mirror if a disk
location is involved that was already handled by the device
replace copy operation. The assigned mirror num is the highest
mirror number, e.g. the value 3 in case of RAID1.
If btrfs_map_bio() is invoked with mirror_num == 0 (i.e., select
any mirror), the copy on the target drive is never selected
because that disk shall be able to perform the write requests as
quickly as possible. The parallel execution of read requests would
only slow down the disk copy procedure. Second case is that
btrfs_map_bio() is called with mirror_num > 0. This is done from
the repair code only. In this case, the highest mirror num is
assigned to the target disk, since it is used last. And when this
mirror is not available because the copy procedure has not yet
handled this area, an error is returned. Everywhere in the code
the handling of such errors is added now.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12 17:15:40 -05:00
Stefan Behrens
e922e087a3 Btrfs: enhance btrfs structures for device replace support
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12 17:15:37 -05:00
Stefan Behrens
aa1b8cd409 Btrfs: pass fs_info instead of root
A small number of functions that are used in a device replace
procedure when the operation is resumed at mount time are unable
to pass the same root pointer that would be used in the regular
(ioctl) context. And since the root pointer is not required, only
the fs_info is, the root pointer argument is replaced with the
fs_info pointer argument.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12 17:15:36 -05:00
Stefan Behrens
5d9640517d Btrfs: Pass fs_info to btrfs_num_copies() instead of mapping_tree
This is required for the device replace procedure in a later step.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12 17:15:34 -05:00
Liu Bo
b53d3f5db2 Btrfs: cleanup for btrfs_btree_balance_dirty
- 'nr' is no more used.
- btrfs_btree_balance_dirty() and __btrfs_btree_balance_dirty() can share
  a bunch of code.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12 17:15:28 -05:00
Julia Lawall
31b1a2bd75 fs/btrfs: use WARN
Use WARN rather than printk followed by WARN_ON(1), for conciseness.

A simplified version of the semantic patch that makes this transformation
is as follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
expression list es;
@@

-printk(
+WARN(1,
  es);
-WARN_ON(1);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12 17:15:23 -05:00
Stefan Behrens
292fd7fc39 Btrfs: don't allow degraded mount if too many devices are missing
The current behavior is to allow mounting or remounting a filesystem
writeable in degraded mode if at least one writeable device is
present.
The next failed write access to a missing device which is above
the tolerance of the configured level of redundancy results in an
read-only enforcement. Even without this, the next time
barrier_all_devices() is called and more devices are missing than
tolerable, the switch to read-only mode takes place.

In order to behave predictably and to provide proper feedback to
the user at mount time, this patch compares the number of missing
devices with the number of devices that are tolerated to be missing
according to the configured RAID level. If more devices are missing
than tolerated, e.g. if two devices are missing in case of RAID1,
only a read-only mount and remount is allowed.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12 17:15:18 -05:00
Miao Xie
8ccf6f19b6 Btrfs: make delalloc inodes be flushed by multi-task
This patch introduce a new worker pool named "flush_workers", and if we
want to force all the inode with pending delalloc to the disks, we can
queue those inodes into the work queue of the worker pool, in this way,
those inodes will be flushed by multi-task.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-11 13:31:37 -05:00
Wang Sheng-Hui
1037a5affc Btrfs: remove repeated eb->pages check in, disk-io.c/csum_dirty_buffer
In csum_dirty_buffer, we first get eb from page->private.
Then we check if the page is the first page of eb. Later
we check it again. Remove the repeated check here.

Signed-off-by: Wang Sheng-Hui <shhuiw@gmail.com>
2012-10-09 09:37:30 -04:00
Stefan Behrens
5af3e8cce8 Btrfs: make filesystem read-only when submitting barrier fails
So far the return code of barrier_all_devices() is ignored, which
means that errors are ignored. The result can be a corrupt
filesystem which is not consistent.
This commit adds code to evaluate the return code of
barrier_all_devices(). The normal btrfs_error() mechanism is used to
switch the filesystem into read-only mode when errors are detected.

In order to decide whether barrier_all_devices() should return
error or success, the number of disks that are allowed to fail the
barrier submission is calculated. This calculation accounts for the
worst RAID level of metadata, system and data. If single, dup or
RAID0 is in use, a single disk error is already considered to be
fatal. Otherwise a single disk error is tolerated.

The calculation of the number of disks that are tolerated to fail
the barrier operation is performed when the filesystem gets mounted,
when a balance operation is started and finished, and when devices
are added or removed.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
2012-10-09 09:20:19 -04:00
Josef Bacik
e6138876ad Btrfs: cache extent state when writing out dirty metadata pages
Everytime we write out dirty pages we search for an offset in the tree,
convert the bits in the state, and then when we wait we search for the
offset again and clear the bits.  So for every dirty range in the io tree we
are doing 4 rb searches, which is suboptimal.  With this patch we are only
doing 2 searches for every cycle (modulo weird things happening).  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-10-09 09:15:41 -04:00
Josef Bacik
de0022b9da Btrfs: do not async metadata csumming in certain situations
There are a coule scenarios where farming metadata csumming off to an async
thread doesn't help.  The first is if our processor supports crc32c, in
which case the csumming will be fast and so the overhead of the async model
is not worth the cost.  The other case is for our tree log.  We will be
making that stuff dirty and writing it out and waiting for it immediately.
Even with software crc32c this gives me a ~15% increase in speed with O_SYNC
workloads.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-10-09 09:15:40 -04:00
Miao Xie
354aa0fb6d Btrfs: fix orphan transaction on the freezed filesystem
With the following debug patch:

 static int btrfs_freeze(struct super_block *sb)
 {
+ 	struct btrfs_fs_info *fs_info = btrfs_sb(sb);
+	struct btrfs_transaction *trans;
+
+	spin_lock(&fs_info->trans_lock);
+	trans = fs_info->running_transaction;
+	if (trans) {
+		printk("Transid %llu, use_count %d, num_writer %d\n",
+			trans->transid, atomic_read(&trans->use_count),
+			atomic_read(&trans->num_writers));
+	}
+	spin_unlock(&fs_info->trans_lock);
 	return 0;
 }

I found there was a orphan transaction after the freeze operation was done.

It is because the transaction may not be committed when the transaction handle
end even though it is the last handle of the current transaction. This design
avoid committing the transaction frequently, but also introduce the above
problem.

So I add btrfs_attach_transaction() which can catch the current transaction
and commit it. If there is no transaction, it will return ENOENT, and do not
anything.

This function also can be used to instead of btrfs_join_transaction_freeze()
because it don't increase the writer counter and don't start a new transaction,
so it also can fix the deadlock between sync and freeze.

Besides that, it is used to instead of btrfs_join_transaction() in
transaction_kthread(), because if there is no transaction, the transaction
kthread needn't anything.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
2012-10-09 09:15:39 -04:00
Josef Bacik
892951a92e Btrfs: remove unused write cache pages hook
The btree inode has it's own write cache pages so we can remove this write
cache pages hook as it's not used.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-10-04 09:39:59 -04:00
Liu Bo
2e90cf858f Btrfs: cleanup fs_info->hashers
fs_info->hashers is now an obsolete one.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
2012-10-04 09:39:57 -04:00
Tsutomu Itoh
b4f359ab06 Btrfs: remove unnecessary code in btree_get_extent()
Unnecessary lookup_extent_mapping() is removed because an error is
returned to the caller.
This patch was made based on the advice from Stefan Behrens, thanks.

Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
2012-10-04 09:39:54 -04:00
Tsutomu Itoh
0433f20d43 Btrfs: cleanup of error processing in btree_get_extent()
This patch simplifies a little complex error processing in
btree_get_extent().

Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
2012-10-04 09:39:54 -04:00
liubo
0647d6bd16 Btrfs: cleanup for unused ref cache stuff
As ref cache has been removed from btrfs, there is no user on
its lock and its check.

Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
2012-10-01 15:19:17 -04:00
Miao Xie
2ecb79239b Btrfs: fix unprotected ->log_batch
We forget to protect ->log_batch when syncing a file, this patch fix
this problem by atomic operation. And ->log_batch is used to check
if there are parallel sync operations or not, so it is unnecessary to
reset it to 0 after the sync operation of the current log tree complete.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
2012-10-01 15:19:12 -04:00
Miao Xie
66d8f3dd1c Btrfs: add a new "type" field into the block reservation structure
Sometimes we need choose the method of the reservation according to the type
of the block reservation, such as the reservation for the delayed inode update.
Now we identify the type just by comparing the address of the reservation
variants, it is very ugly if it is a temporary one because we need compare it
with all the common reservation variants. So we add a new "type" field to keep
the type the reservation variants.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
2012-10-01 15:19:11 -04:00
Linus Torvalds
318e151019 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "I've split out the big send/receive update from my last pull request
  and now have just the fixes in my for-linus branch.  The send/recv
  branch will wander over to linux-next shortly though.

  The largest patches in this pull are Josef's patches to fix DIO
  locking problems and his patch to fix a crash during balance.  They
  are both well tested.

  The rest are smaller fixes that we've had queued.  The last rc came
  out while I was hacking new and exciting ways to recover from a
  misplaced rm -rf on my dev box, so these missed rc3."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (25 commits)
  Btrfs: fix that repair code is spuriously executed for transid failures
  Btrfs: fix ordered extent leak when failing to start a transaction
  Btrfs: fix a dio write regression
  Btrfs: fix deadlock with freeze and sync V2
  Btrfs: revert checksum error statistic which can cause a BUG()
  Btrfs: remove superblock writing after fatal error
  Btrfs: allow delayed refs to be merged
  Btrfs: fix enospc problems when deleting a subvol
  Btrfs: fix wrong mtime and ctime when creating snapshots
  Btrfs: fix race in run_clustered_refs
  Btrfs: don't run __tree_mod_log_free_eb on leaves
  Btrfs: increase the size of the free space cache
  Btrfs: barrier before waitqueue_active
  Btrfs: fix deadlock in wait_for_more_refs
  btrfs: fix second lock in btrfs_delete_delayed_items()
  Btrfs: don't allocate a seperate csums array for direct reads
  Btrfs: do not strdup non existent strings
  Btrfs: do not use missing devices when showing devname
  Btrfs: fix that error value is changed by mistake
  Btrfs: lock extents as we map them in DIO
  ...
2012-08-29 11:36:22 -07:00
Stefan Behrens
256dd1bb37 Btrfs: fix that repair code is spuriously executed for transid failures
If verify_parent_transid() fails for all mirrors, the current code
calls repair_io_failure() anyway which means:
- that the disk block is rewritten without repairing anything and
- that a kernel log message is printed which misleadingly claims
  that a read error was corrected.

This is an example:
parent transid verify failed on 615015833600 wanted 110423 found 110424
parent transid verify failed on 615015833600 wanted 110423 found 110424
btrfs read error corrected: ino 1 off 615015833600 (dev /dev/...)

It is wrong to ignore the results from verify_parent_transid() and to
call repair_eb_io_failure() when the verification of the transids failed.
This commit fixes the issue.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-08-28 16:53:43 -04:00
Stefan Behrens
68ce9682a4 Btrfs: remove superblock writing after fatal error
With commit acce952b0, btrfs was changed to flag the filesystem with
BTRFS_SUPER_FLAG_ERROR and switch to read-only mode after a fatal
error happened like a write I/O errors of all mirrors.
In such situations, on unmount, the superblock is written in
btrfs_error_commit_super(). This is done with the intention to be able
to evaluate the error flag on the next mount. A warning is printed
in this case during the next mount and the log tree is ignored.

The issue is that it is possible that the superblock points to a root
that was not written (due to write I/O errors).
The result is that the filesystem cannot be mounted. btrfsck also does
not start and all the other btrfs-progs tools fail to start as well.
However, mount -o recovery is working well and does the right things
to recover the filesystem (i.e., don't use the log root, clear the
free space cache and use the next mountable root that is stored in the
root backup array).

This patch removes the writing of the superblock when
BTRFS_SUPER_FLAG_ERROR is set, and removes the handling of the error
flag in the mount function.

These lines can be used to reproduce the issue (using /dev/sdm):
SCRATCH_DEV=/dev/sdm
SCRATCH_MNT=/mnt
echo 0 25165824 linear $SCRATCH_DEV 0 | dmsetup create foo
ls -alLF /dev/mapper/foo
mkfs.btrfs /dev/mapper/foo
mount /dev/mapper/foo $SCRATCH_MNT
echo bar > $SCRATCH_MNT/foo
sync
echo 0 25165824 error | dmsetup reload foo
dmsetup resume foo
ls -alF $SCRATCH_MNT
touch $SCRATCH_MNT/1
ls -alF $SCRATCH_MNT
sleep 35
echo 0 25165824 linear $SCRATCH_DEV 0 | dmsetup reload foo
dmsetup resume foo
sleep 1
umount $SCRATCH_MNT
btrfsck /dev/mapper/foo
dmsetup remove foo

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-08-28 16:53:38 -04:00
Josef Bacik
66657b318e Btrfs: barrier before waitqueue_active
We need a barrir before calling waitqueue_active otherwise we will miss
wakeups.  So in places that do atomic_dec(); then atomic_read() use
atomic_dec_return() which imply a memory barrier (see memory-barriers.txt)
and then add an explicit memory barrier everywhere else that need them.
Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-08-28 16:53:33 -04:00
Arne Jansen
1fa11e265f Btrfs: fix deadlock in wait_for_more_refs
Commit a168650c introduced a waiting mechanism to prevent busy waiting in
btrfs_run_delayed_refs. This can deadlock with btrfs_run_ordered_operations,
where a tree_mod_seq is held while waiting for the io to complete, while
the end_io calls btrfs_run_delayed_refs.
This whole mechanism is unnecessary. If not enough runnable refs are
available to satisfy count, just return as count is more like a guideline
than a strict requirement.
In case we have to run all refs, commit transaction makes sure that no
other threads are working in the transaction anymore, so we just assert
here that no refs are blocked.

Signed-off-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-08-28 16:53:32 -04:00
Linus Torvalds
a0e881b7c1 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull second vfs pile from Al Viro:
 "The stuff in there: fsfreeze deadlock fixes by Jan (essentially, the
  deadlock reproduced by xfstests 068), symlink and hardlink restriction
  patches, plus assorted cleanups and fixes.

  Note that another fsfreeze deadlock (emergency thaw one) is *not*
  dealt with - the series by Fernando conflicts a lot with Jan's, breaks
  userland ABI (FIFREEZE semantics gets changed) and trades the deadlock
  for massive vfsmount leak; this is going to be handled next cycle.
  There probably will be another pull request, but that stuff won't be
  in it."

Fix up trivial conflicts due to unrelated changes next to each other in
drivers/{staging/gdm72xx/usb_boot.c, usb/gadget/storage_common.c}

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (54 commits)
  delousing target_core_file a bit
  Documentation: Correct s_umount state for freeze_fs/unfreeze_fs
  fs: Remove old freezing mechanism
  ext2: Implement freezing
  btrfs: Convert to new freezing mechanism
  nilfs2: Convert to new freezing mechanism
  ntfs: Convert to new freezing mechanism
  fuse: Convert to new freezing mechanism
  gfs2: Convert to new freezing mechanism
  ocfs2: Convert to new freezing mechanism
  xfs: Convert to new freezing code
  ext4: Convert to new freezing mechanism
  fs: Protect write paths by sb_start_write - sb_end_write
  fs: Skip atime update on frozen filesystem
  fs: Add freezing handling to mnt_want_write() / mnt_drop_write()
  fs: Improve filesystem freezing handling
  switch the protection of percpu_counter list to spinlock
  nfsd: Push mnt_want_write() outside of i_mutex
  btrfs: Push mnt_want_write() outside of i_mutex
  fat: Push mnt_want_write() outside of i_mutex
  ...
2012-08-01 10:26:23 -07:00
Jan Kara
b2b5ef5c8e btrfs: Convert to new freezing mechanism
We convert btrfs_file_aio_write() to use new freeze check.  We also add proper
freeze protection to btrfs_page_mkwrite(). We also add freeze protection to
the transaction mechanism to avoid starting transactions on frozen filesystem.
At minimum this is necessary to stop iput() of unlinked file to change frozen
filesystem during truncation.

Checks in cleaner_kthread() and transaction_kthread() can be safely removed
since btrfs_freeze() will lock the mutexes and thus block the threads (and they
shouldn't have anything to do anyway).

CC: linux-btrfs@vger.kernel.org
CC: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-31 09:45:52 +04:00
Joe Perches
533574c6bc btrfs: use printk_get_level and printk_skip_level, add __printf, fix fallout
Use the generic printk_get_level() to search a message for a kern_level.

Add __printf to verify format and arguments.  Fix a few messages that
had mismatches in format and arguments.  Add #ifdef CONFIG_PRINTK blocks
to shrink the object size a bit when not using printk.

[akpm@linux-foundation.org: whitespace tweak]
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-30 17:25:14 -07:00
Chris Mason
113c1cb530 Merge branch 'send-v2' of git://github.com/ablock84/linux-btrfs into for-linus
This is the kernel portion of btrfs send/receive

Conflicts:
	fs/btrfs/Makefile
	fs/btrfs/backref.h
	fs/btrfs/ctree.c
	fs/btrfs/ioctl.c
	fs/btrfs/ioctl.h

Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-07-25 19:19:10 -04:00
Alexander Block
8ea05e3a42 Btrfs: introduce subvol uuids and times
This patch introduces uuids for subvolumes. Each
subvolume has it's own uuid. In case it was snapshotted,
it also contains parent_uuid. In case it was received,
it also contains received_uuid.

It also introduces subvolume ctime/otime/stime/rtime. The
first two are comparable to the times found in inodes. otime
is the origin/creation time and ctime is the change time.
stime/rtime are only valid on received subvolumes.
stime is the time of the subvolume when it was
sent. rtime is the time of the subvolume when it was
received.

Additionally to the times, we have a transid for each
time. They are updated at the same place as the times.

btrfs receive uses stransid and rtransid to find out
if a received subvolume changed in the meantime.

If an older kernel mounts a filesystem with the
extented fields, all fields become invalid. The next
mount with a new kernel will detect this and reset the
fields.

Signed-off-by: Alexander Block <ablock84@googlemail.com>
Reviewed-by: David Sterba <dave@jikos.cz>
Reviewed-by: Arne Jansen <sensille@gmx.net>
Reviewed-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Reviewed-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com>
2012-07-25 23:28:38 +02:00
Chris Mason
b478b2baa3 Merge branch 'qgroup' of git://git.jan-o-sch.net/btrfs-unstable into for-linus
Conflicts:
	fs/btrfs/ioctl.c
	fs/btrfs/ioctl.h
	fs/btrfs/transaction.c
	fs/btrfs/transaction.h

Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-07-25 16:11:38 -04:00
Stefan Behrens
c0901581ad Btrfs: avoid I/O repair BUG() from btree_read_extent_buffer_pages()
From btree_read_extent_buffer_pages(), currently repair_io_failure()
can be called with mirror_num being zero when submit_one_bio() returned
an error before. This used to cause a BUG_ON(!mirror_num) in
repair_io_failure() and indeed this is not a case that needs the I/O
repair code to rewrite disk blocks.
This commit prevents calling repair_io_failure() in this case and thus
avoids the BUG_ON() and malfunction.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-07-23 16:27:59 -04:00
Ilya Dryomov
44c44af2f4 Btrfs: do not ignore errors from btrfs_cleanup_fs_roots() when mounting
There used to be a BUG_ON(ret) there before EH patch (79787eaa) went in.
Bail out with EINVAL.

Cc: David Sterba <dsterba@suse.cz>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-07-23 16:27:53 -04:00