Commit Graph

323361 Commits

Author SHA1 Message Date
Zach Brown
221b831835 btrfs: fix min csum item size warnings in 32bit
commit 7ca4be45a0 limited csum items to
PAGE_CACHE_SIZE.  It used min() with incompatible types in 32bit which
generates warnings:

fs/btrfs/file-item.c: In function ‘btrfs_csum_file_blocks’:
fs/btrfs/file-item.c:717: warning: comparison of distinct pointer types lacks a cast

This uses min_t(u32,) to fix the warnings.  u32 seemed reasonable
because btrfs_root->leafsize is u32 and PAGE_CACHE_SIZE is unsigned
long.

Signed-off-by: Zach Brown <zab@zabbo.net>
2012-10-09 09:15:39 -04:00
Josef Bacik
67b0fd63d5 Btrfs: run delayed refs first when out of space
Running delayed refs is faster than running delalloc, so lets do that first
to try and reclaim space.  This makes my fs_mark test about 20% faster.
Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-10-09 09:15:39 -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
Miao Xie
a698d0755a Btrfs: add a type field for the transaction handle
This patch add a type field into the transaction handle structure,
in this way, we needn't implement various end-transaction functions
and can make the code more simple and readable.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
2012-10-09 09:15:38 -04:00
Miao Xie
e8830e606f Btrfs: fix memory leak in start_transaction()
This patch fixes memory leak of the transaction handle which happened
when starting transaction failed on a freezed fs.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
2012-10-09 09:15:38 -04:00
Mark Fasheh
d24bec3ae5 btrfs: extended inode ref iteration
The iterate_irefs in backref.c is used to build path components from inode
refs. This patch adds code to iterate extended refs as well.

I had modify the callback function signature to abstract out some of the
differences between ref structures. iref_to_path() also needed similar
changes.

Signed-off-by: Mark Fasheh <mfasheh@suse.de>
2012-10-09 09:15:01 -04:00
Mark Fasheh
f186373fef btrfs: extended inode refs
This patch adds basic support for extended inode refs. This includes support
for link and unlink of the refs, which basically gets us support for rename
as well.

Inode creation does not need changing - extended refs are only added after
the ref array is full.

Signed-off-by: Mark Fasheh <mfasheh@suse.de>
2012-10-09 09:14:45 -04:00
Jan Schmidt
5a1d7843ca btrfs: improved readablity for add_inode_ref
Moved part of the code into a sub function and replaced most of the gotos
by ifs, hoping that it will be easier to read now.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
2012-10-08 20:09:02 -04:00
Josef Bacik
0aa4a17d82 Btrfs: handle not finding the extent exactly when logging changed extents
I started hitting warnings when running xfstest 68 in a loop because there
were EM's that were not lined up properly with the physical extents.  This
is ok, if we do something like punch a hole or write to a preallocated space
or something like that we can have an EM that doesn't cover the entire
physical extent.  So fix the tree logging stuff to cope with this case so we
don't just commit the transaction.  With this patch I no longer see the
warnings from the tree logging code.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-10-08 20:09:02 -04:00
David Sterba
005d6427ac btrfs: move transaction aborts to the point of failure
Call btrfs_abort_transaction as early as possible when an error
condition is detected, that way the line number reported is useful
and we're not clueless anymore which error path led to the abort.

Signed-off-by: David Sterba <dsterba@suse.cz>
2012-10-08 20:09:02 -04:00
Miao Xie
8732d44f80 Btrfs: fix the missing error information in create_pending_snapshot()
The macro btrfs_abort_transaction() can get the line number of the code
where the problem happens, so we should invoke it in the place that the
error occurs, or we will lose the line number.

Reported-by: David Sterba <dave@jikos.cz>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
2012-10-08 20:07:33 -04:00
Liu Bo
aa42ffd918 Btrfs: fix off-by-one in file clone
Btrfs uses inclusive range end for lock_extent(), unlock_extent() and
related functions, so we made off-by-one errors in file clone.

This fixes it and also fixes some style problems.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
2012-10-08 20:07:32 -04:00
David Sterba
7e97b8daf6 btrfs: allow setting NOCOW for a zero sized file via ioctl
Hi,

the patch si simple, but it has user visible impact and I'm not quite sure how
to resolve it.

In short, $subj says it, chattr -C supports it and we want to use it.

The conditions that acutally allow to change the NOCOW flag are clear. What if
I try to set the flag on a file that is not empty? Options:

1) whole ioctl will fail, EINVAL
2.1) ioctl will succeed, the NOCOW flag will be silently removed, but the file
     will stay COW-ed and checksummed
2.2) ioctl will succeed, flag will not be removed and a syslog message will
     warn that the COW flag has not been changed
2.2.1) dtto, no syslog message

Man page of chattr states that

 "If it is set on a file which already has data blocks, it is undefined when
 the blocks assigned to the file will be fully stable."

Yes, it's undefined and with current implementation it'll never happen. So from
this end, the user cannot expect anything. I'm trying to find a reasonable
behaviour, so that a command like 'chattr -R -aijS +C' to tweak a broad set of
flags in a deep directory does not fail unnecessarily and does not pollute the
log.

My personal preference is 2.2.1, but my dev's oppinion is skewed, not counting
the fact that I know the code and otherwise would look there before consulting
the documentation.

The patch implements 2.2.1.

david

-------------8<-------------------
From: David Sterba <dsterba@suse.cz>

It's safe to turn off checksums for a zero sized file.

http://thread.gmane.org/gmane.comp.file-systems.btrfs/18030

"We cannot switch on NODATASUM for a file that already has extents that
are checksummed. The invariant here is that either all the extents or
none are checksummed.

Theoretically it's possible to add/remove all checksums from a given
file, but it's a potentially longtime operation, the file has to be in
some intermediate state where the checksums partially exist but have to
be ignored (for the csum->nocsum) until the file is fully converted,
this brings more special cases to extent handling, it has to survive
power failure and remain consistent, and probably needs to be restarted
after next mount."

Signed-off-by: David Sterba <dsterba@suse.cz>
2012-10-04 09:40:00 -04:00
Josef Bacik
c3308f84c1 Btrfs: fix punch hole when no extent exists
I saw the warning in btrfs_drop_extent_cache where our end is less than our
start while running xfstests 68 in a loop.  This is because we
unconditionally do drop_end = min(end, extent_end) in
__btrfs_drop_extents(), even though we may not have found an extent in the
range we were looking to drop.  So keep track of wether or not we found
something, and if we didn't just use our end.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-10-04 09:40:00 -04:00
Josef Bacik
926ced123b Btrfs: don't do anything in our ->freeze_fs and ->unfreeze_fs
We do not need to do anything special to freeze or unfreeze, it's all taken
care of by the generic work, and what we currently have is wrong anyway
since we shouldn't be returnning to userspace with mutexes held anyway.
Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-10-04 09:40:00 -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
Josef Bacik
b5bae2612a Btrfs: fix race when getting the eb out of page->private
We can race when checking wether PagePrivate is set on a page and we
actually have an eb saved in the pages private pointer.  We could have
easily written out this page and released it in the time that we did the
pagevec lookup and actually got around to looking at this page.  So use
mapping->private_lock to ensure we get a consistent view of the
page->private pointer.  This is inline with the alloc and releasepage paths
which use private_lock when manipulating page->private.  Thanks,

Reported-by: David Sterba <dave@jikos.cz>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-10-04 09:39:59 -04:00
Josef Bacik
ff44c6e36d Btrfs: do not hold the write_lock on the extent tree while logging
Dave Sterba pointed out a sleeping while atomic bug while doing fsync.  This
is because I'm an idiot and didn't realize that rwlock's were spin locks, so
we've been holding this thing while doing allocations and such which is not
good.  This patch fixes this by dropping the write lock before we do
anything heavy and re-acquire it when it is done.  We also need to take a
ref on the em's in case their corresponding pages are evicted and mark them
as being logged so that releasepage does not remove them and doesn't remove
them from our local list.  Thanks,

Reported-by: Dave Sterba <dave@jikos.cz>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-10-04 09:39:58 -04:00
Josef Bacik
98114659e0 Btrfs: fix race with freeze and free space inodes
So we start our freeze, somebody comes in and does an fsync() on a file
where we have to commit a transaction for whatever reason, and we will
deadlock because the freeze is waiting on FS_FREEZE people to stop writing
to the file system, but the transaction is waiting for its free space inodes
to be written out, which are in turn waiting on sb_start_intwrite while
trying to write the file extents.  To fix this we'll just skip the
sb_start_intwrite() if we TRANS_JOIN_NOLOCK since we're being waited on by a
transaction commit so we're safe wrt to freeze and this will keep us from
deadlocking.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-10-04 09:39:58 -04:00
Liu Bo
6bbe3a9c80 Btrfs: kill obsolete arguments in btrfs_wait_ordered_extents
nocow_only is now an obsolete argument.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
2012-10-04 09:39:57 -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
Liu Bo
ab26e9d6c8 Btrfs: cleanup for duplicated code in find_free_extent
There is already an 'add free space' phrase in front of this one, we
needn't to redo it.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
2012-10-04 09:39:57 -04:00
Josef Bacik
60376ce4a8 Btrfs: fix race in sync and freeze again
I screwed this up, there is a race between checking if there is a running
transaction and actually starting a transaction in sync where we could race
with a freezer and get ourselves into trouble.  To fix this we need to make
a new join type to only do the try lock on the freeze stuff.  If it fails
we'll return EPERM and just return from sync.  This fixes a hang Liu Bo
reported when running xfstest 68 in a loop.  Thanks,

Reported-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-10-04 09:39:56 -04:00
David Sterba
b3ae244e71 btrfs: return EPERM upon rmdir on a subvolume
A subvolume cannot be deleted via rmdir, but the error code ENOTEMPTY
is confusing. Return EPERM instead, as this is not permitted.

Signed-off-by: David Sterba <dsterba@suse.cz>
2012-10-04 09:39:56 -04:00
Wei Yongjun
ebb3dad435 Btrfs: using for_each_set_bit_from to simplify the code
Using for_each_set_bit_from() to simplify the code.

spatch with a semantic match is used to found this.
(http://coccinelle.lip6.fr/)

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
2012-10-04 09:39:55 -04:00
Anand Jain
1bcea35597 Btrfs: write_buf is now callable outside send.c
Developing service cmds needs it.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
2012-10-04 09:39:55 -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
Miao Xie
90abccf2c6 Revert "Btrfs: do not do filemap_write_and_wait_range in fsync"
This reverts commit 0885ef5b56

After applying the above patch, the performance slowed down because the dirty
page flush can only be done by one task, so revert it.

The following is the test result of sysbench:
	Before		After
	24MB/s		39MB/s

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
2012-10-01 15:19:22 -04:00
Josef Bacik
698d0082c4 Btrfs: remove bytes argument from do_chunk_alloc
Everybody is just making stuff up, and it's just used to see if we really do
need to alloc a chunk, and since we do this when we already know we really
do it's just a waste of space.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-10-01 15:19:21 -04:00
Josef Bacik
ea658badc4 Btrfs: delay block group item insertion
So we have lots of places where we try to preallocate chunks in order to
make sure we have enough space as we make our allocations.  This has
historically meant that we're constantly tweaking when we should allocate a
new chunk, and historically we have gotten this horribly wrong so we way
over allocate either metadata or data.  To try and keep this from happening
we are going to make it so that the block group item insertion is done out
of band at the end of a transaction.  This will allow us to create chunks
even if we are trying to make an allocation for the extent tree.  With this
patch my enospc tests run faster (didn't expect this) and more efficiently
use the disk space (this is what I wanted).  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-10-01 15:19:21 -04:00
Kent Overstreet
be3940c0a9 btrfs: Kill some bi_idx references
For immutable bio vecs, I've been auditing and removing bi_idx
references. These were harmless, but removing them will make auditing
easier.

scrub_bio_end_io_worker() was open coding a bio_reset() - but this
doesn't appear to have been needed for anything as right after it does a
bio_put(), and perusing the code it doesn't appear anything else was
holding a reference to the bio.

The other use end_bio_extent_readpage() was just for a pr_debug() -
changed it to something that might be a bit more useful.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
CC: Chris Mason <chris.mason@oracle.com>
CC: Stefan Behrens <sbehrens@giantdisaster.de>
2012-10-01 15:19:21 -04:00
Miao Xie
962197babe Btrfs: fix unnecessary warning when the fragments make the space alloc fail
When we wrote some data by compress mode into a btrfs filesystem which was full
of the fragments, the kernel will report:
	BTRFS warning (device xxx): Aborting unused transaction.

The reason is:
We can not find a long enough free space to store the compressed data because
of the fragmentary free space, and the compressed data can not be splited,
so the kernel outputed the above message.

In fact, btrfs can deal with this problem very well: it fall back to
uncompressed IO, split the uncompressed data into small ones, and then
store them into to the fragmentary free space. So we shouldn't output the
above warning message.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
2012-10-01 15:19:20 -04:00
Josef Bacik
69ffb54347 Btrfs: create a pinned em when writing to a prealloc range in DIO
Wade Cline reported a problem where he was getting garbage and warnings when
writing to a preallocated range via O_DIRECT.  This is because we weren't
creating our normal pinned extent_map for the range we were writing to,
which was causing all sorts of issues.  This patch fixes the problem and
makes his testcase much happier.  Thanks,

Reported-by: Wade Cline <clinew@linux.vnet.ibm.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-10-01 15:19:20 -04:00
Josef Bacik
6df7881a84 Btrfs: move the sb_end_intwrite until after the throttle logic
Sage reported the following lockdep backtrace

=====================================
[ BUG: bad unlock balance detected! ]
3.6.0-rc2-ceph-00171-gc7ed62d #1 Not tainted
-------------------------------------
btrfs-cleaner/7607 is trying to release lock (sb_internal) at:
[<ffffffffa00422ae>] btrfs_commit_transaction+0xa6e/0xb20 [btrfs]
but there are no more locks to release!

other info that might help us debug this:
1 lock held by btrfs-cleaner/7607:
 #0:  (&fs_info->cleaner_mutex){+.+...}, at: [<ffffffffa003b405>] cleaner_kthread+0x95/0x120 [btrfs]

stack backtrace:
Pid: 7607, comm: btrfs-cleaner Not tainted 3.6.0-rc2-ceph-00171-gc7ed62d #1
Call Trace:
 [<ffffffffa00422ae>] ? btrfs_commit_transaction+0xa6e/0xb20 [btrfs]
 [<ffffffff810afa9e>] print_unlock_inbalance_bug+0xfe/0x110
 [<ffffffff810b289e>] lock_release_non_nested+0x1ee/0x310
 [<ffffffff81172f9b>] ? kmem_cache_free+0x7b/0x160
 [<ffffffffa004106c>] ? put_transaction+0x8c/0x130 [btrfs]
 [<ffffffffa00422ae>] ? btrfs_commit_transaction+0xa6e/0xb20 [btrfs]
 [<ffffffff810b2a95>] lock_release+0xd5/0x220
 [<ffffffff81173071>] ? kmem_cache_free+0x151/0x160
 [<ffffffff8117d9ed>] __sb_end_write+0x7d/0x90
 [<ffffffffa00422ae>] btrfs_commit_transaction+0xa6e/0xb20 [btrfs]
 [<ffffffff81079850>] ? __init_waitqueue_head+0x60/0x60
 [<ffffffff81634c6b>] ? _raw_spin_unlock+0x2b/0x40
 [<ffffffffa0042758>] __btrfs_end_transaction+0x368/0x3c0 [btrfs]
 [<ffffffffa0042808>] btrfs_end_transaction_throttle+0x18/0x20 [btrfs]
 [<ffffffffa00318f0>] btrfs_drop_snapshot+0x410/0x600 [btrfs]
 [<ffffffff8132babd>] ? do_raw_spin_unlock+0x5d/0xb0
 [<ffffffffa00430ef>] btrfs_clean_old_snapshots+0xaf/0x150 [btrfs]
 [<ffffffffa003b405>] ? cleaner_kthread+0x95/0x120 [btrfs]
 [<ffffffffa003b419>] cleaner_kthread+0xa9/0x120 [btrfs]
 [<ffffffffa003b370>] ? btrfs_destroy_delayed_refs.isra.102+0x220/0x220 [btrfs]
 [<ffffffff810791ee>] kthread+0xae/0xc0
 [<ffffffff810b379d>] ? trace_hardirqs_on+0xd/0x10
 [<ffffffff8163e744>] kernel_thread_helper+0x4/0x10
 [<ffffffff81635430>] ? retint_restore_args+0x13/0x13
 [<ffffffff81079140>] ? flush_kthread_work+0x1a0/0x1a0
 [<ffffffff8163e740>] ? gs_change+0x13/0x13

This is because the throttle stuff can commit the transaction, which expects to
be the one stopping the intwrite stuff, but we've already done it in the
__btrfs_end_transaction.  Moving the sb_end_intewrite after this logic makes the
lockdep go away.  Thanks,

Tested-by: Sage Weil <sage@inktank.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-10-01 15:19:19 -04:00
Liu Bo
425d17a290 Btrfs: use larger limit for translation of logical to inode
This is the change of the kernel side.

Translation of logical to inode used to have an upper limit 4k on
inode container's size, but the limit is not large enough for a data
with a great many of refs, so when resolving logical address,
we can end up with
"ioctl ret=0, bytes_left=0, bytes_missing=19944, cnt=510, missed=2493"

This changes to regard 64k as the upper limit and use vmalloc instead of
kmalloc to get memory more easily.

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
2012-10-01 15:19:19 -04:00
Liu Bo
df031f0752 Btrfs: use helper for logical resolve
We already have a helper, iterate_inodes_from_logical(), for logical resolve,
so just use it.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
2012-10-01 15:19:18 -04:00
Liu Bo
69917e4312 Btrfs: fix a bug in parsing return value in logical resolve
In logical resolve, we parse extent_from_logical()'s 'ret' as a kind of flag.

It is possible to lose our errors because
(-EXXXX & BTRFS_EXTENT_FLAG_TREE_BLOCK) is true.

I'm not sure if it is on purpose, it just looks too hacky if it is.
I'd rather use a real flag and a 'ret' to catch errors.

Acked-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Liu Bo <liub.liubo@gmail.com>
2012-10-01 15:19:18 -04:00
Liu Bo
dea7d76ecb Btrfs: update delayed ref's tracepoints to show sequence
We've added a new field 'sequence' to delayed ref node, so update related
tracepoints.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
2012-10-01 15:19:17 -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
8407aa4643 Btrfs: fix corrupted metadata in the snapshot
When we delete a inode, we will remove all the delayed items including delayed
inode update, and then truncate all the relative metadata. If there is lots of
metadata, we will end the current transaction, and start a new transaction to
truncate the left metadata. In this way, we will leave a inode item that its
link counter is > 0, and also may leave some directory index items in fs/file tree
after the current transaction ends. In other words, the metadata in this fs/file tree
is inconsistent. If we create a snapshot for this tree now, we will find a inode with
corrupted metadata in the new snapshot, and we won't continue to drop the left metadata,
because its link counter is not 0.

We fix this problem by updating the inode item before the current transaction ends.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
2012-10-01 15:19:17 -04:00
David Sterba
837e197283 btrfs: polish names of kmem caches
Usecase:

  watch 'grep btrfs < /proc/slabinfo'

easy to watch all caches in one go.

Signed-off-by: David Sterba <dsterba@suse.cz>
2012-10-01 15:19:16 -04:00
Josef Bacik
a80c8dcf7e Btrfs: fix our overcommit math
I noticed I was seeing large lags when running my torrent test in a vm on my
laptop.  While trying to make it lag less I noticed that our overcommit math
was taking into account the number of bytes we wanted to reclaim, not the
number of bytes we actually wanted to allocate, which means we wouldn't
overcommit as often.  This patch fixes the overcommit math and makes
shrink_delalloc() use that logic so that it will stop looping faster.  We
still have pretty high spikes of latency, but the test now takes 3 minutes
less time (about 5% faster).  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-10-01 15:19:16 -04:00
Josef Bacik
dea31f5233 Btrfs: wait on async pages when shrinking delalloc
Mitch reported a problem where you could get an ENOSPC error when untarring
a kernel git tree onto a 16gb file system with compress-force=zlib.  This is
because compression is a huge pain, it will return from ->writepages()
without having actually created any ordered extents.  To get around this we
check to see if the async submit counter is up, and if it is wait until it
drops to 0 before doing our normal ordered wait dance.  With this patch I
can now untar a kernel git tree onto a 16gb file system without getting
ENOSPC errors.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-10-01 15:19:15 -04:00
Liu Bo
9e8a4a8b0b Btrfs: use flag EXTENT_DEFRAG for snapshot-aware defrag
We're going to use this flag EXTENT_DEFRAG to indicate which range
belongs to defragment so that we can implement snapshow-aware defrag:

We set the EXTENT_DEFRAG flag when dirtying the extents that need
defragmented, so later on writeback thread can differentiate between
normal writeback and writeback started by defragmentation.

Original-Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
2012-10-01 15:19:15 -04:00
Tsutomu Itoh
3d6b5c3b5c Btrfs: check return value of ulist_alloc() properly
ulist_alloc() has the possibility of returning NULL.
So, it is necessary to check the return value.

Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
2012-10-01 15:19:14 -04:00
Tsutomu Itoh
f54fb859da Btrfs: fix error handling in delete_block_group_cache()
btrfs_iget() never return NULL.
So, NULL check is unnecessary.

Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
2012-10-01 15:19:14 -04:00
Miao Xie
903889f462 Btrfs: fix wrong size for the reservation when doing, file pre-allocation.
When we ran fsstress(a program in xfstests), the filesystem hung up when it
is full. It was because the space reserved in btrfs_fallocate() was wrong,
btrfs_fallocate() just used the size of the pre-allocation to reserve the
space, didn't took the block size aligning into account, so the size of
the reserved space was less than the allocated space, it caused the over
reserve problem and made the filesystem hung up when invoking cow_file_range().
Fix it.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
2012-10-01 15:19:14 -04:00
Miao Xie
69ce977a17 Btrfs: output more information when aborting a unused transaction handle
Though we dump the stack information when aborting a unused transaction
handle, we don't know the correct place where we decide to abort the
transaction handle if one function has several place where the transaction
abort function is invoked and jumps to the same place after this call.
And beside that we also don't know the reason why we jump to abort
the current handle. So I modify the transaction abort function and make
it output the function name, line and error information.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
2012-10-01 15:19:13 -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