Commit Graph

811 Commits

Author SHA1 Message Date
Miao Xie
199c2a9c3d Btrfs: introduce per-subvolume ordered extent list
The reason we introduce per-subvolume ordered extent list is the same
as the per-subvolume delalloc inode list.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-06-14 11:29:41 -04:00
Miao Xie
eb73c1b7ce Btrfs: introduce per-subvolume delalloc inode list
When we create a snapshot, we need flush all delalloc inodes in the
fs, just flushing the inodes in the source tree is OK. So we introduce
per-subvolume delalloc inode list.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-06-14 11:29:40 -04:00
Miao Xie
b0feb9d96e Btrfs: introduce grab/put functions for the root of the fs/file tree
The grab/put funtions will be used in the next patch, which need grab
the root object and ensure it is not freed. We use reference counter
instead of the srcu lock is to aovid blocking the memory reclaim task,
which invokes synchronize_srcu().

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-06-14 11:29:38 -04:00
Miao Xie
cb517eabba Btrfs: cleanup the similar code of the fs root read
There are several functions whose code is similar, such as
  btrfs_find_last_root()
  btrfs_read_fs_root_no_radix()

Besides that, some functions are invoked twice, it is unnecessary,
for example, we are sure that all roots which is found in
  btrfs_find_orphan_roots()
have their orphan items, so it is unnecessary to check the orphan
item again.

So cleanup it.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-06-14 11:29:37 -04:00
Miao Xie
babbf170c7 Btrfs: make the snap/subv deletion end more early when the fs is R/O
The snapshot/subvolume deletion might spend lots of time, it would make
the remount task wait for a long time. This patch improve this problem,
we will break the deletion if the fs is remounted to be R/O. It will make
the users happy.

Cc: David Sterba <dsterba@suse.cz>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-06-14 11:29:36 -04:00
Andreas Philipp
1c89cdd1ce Minor format cleanup.
Clean up the format of the definitions of BTRFS_BLOCK_GROUP_RAID5 and
BTRFS_BLOCK_GROUP_RAID6.

Signed-off-by: Andreas Philipp <philipp.andreas@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-06-14 11:29:25 -04:00
Jan Schmidt
57254b6ebc Btrfs: add ioctl to wait for qgroup rescan completion
btrfs_qgroup_wait_for_completion waits until the currently running qgroup
operation completes. It returns immediately when no rescan process is in
progress. This is useful to automate things around the rescan process (e.g.
testing).

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-06-14 11:29:22 -04:00
Wang Shilong
1e8f915868 Btrfs: introduce qgroup_ulist to avoid frequently allocating/freeing ulist
When doing qgroup accounting, we call ulist_alloc()/ulist_free() every time
when we want to walk qgroup tree.

By introducing 'qgroup_ulist', we only need to call ulist_alloc()/ulist_free()
once. This reduce some sys time to allocate memory, see the measurements below

fsstress -p 4 -n 10000 -d $dir

With this patch:

real    0m50.153s
user    0m0.081s
sys     0m6.294s

real    0m51.113s
user    0m0.092s
sys     0m6.220s

real    0m52.610s
user    0m0.096s
sys     0m6.125s	avg 6.213
-----------------------------------------------------
Without the patch:

real    0m54.825s
user    0m0.061s
sys     0m10.665s

real    1m6.401s
user    0m0.089s
sys     0m11.218s

real    1m13.768s
user    0m0.087s
sys     0m10.665s       avg 10.849

we can see the sys time reduce ~43%.

Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-06-14 11:29:21 -04:00
Josef Bacik
b1c79e0947 Btrfs: handle running extent ops with skinny metadata
Chris hit a bug where we weren't finding extent records when running extent ops.
This is because we use the delayed_ref_head when running the extent op, which
means we can't use the ->type checks to see if we are metadata.  We also lose
the level of the metadata we are working on.  So to fix this we can just check
the ->is_data section of the extent_op, and we can store the level of the buffer
we were modifying in the extent_op.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-17 21:40:15 -04:00
David Sterba
60b62978bc btrfs: annotate quota tree for lockdep
Quota tree has been missing from lockdep annotations, though no warning
has been seen in the wild.

There's currently one entry that does not belong there,
BTRFS_ORPHAN_OBJECTID.  No such tree exists, it's probably a copy &
paste mistake, the id is defined among tree ids.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-17 16:27:25 -04:00
David Sterba
1104a88551 btrfs: enhance superblock checks
The superblock checksum is not verified upon mount. <awkward silence>

Add that check and also reorder existing checks to a more logical
order.

Current mkfs.btrfs does not calculate the correct checksum of
super_block and thus a freshly created filesytem will fail to mount when
this patch is applied.

First transaction commit calculates correct superblock checksum and
saves it to disk.

Reproducer:
$ mfks.btrfs /dev/sda
$ mount /dev/sda /mnt
$ btrfs scrub start /mnt
$ sleep 5
$ btrfs scrub status /mnt
... super:2 ...

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-05-07 10:50:27 -04:00
David Sterba
b6919a58f0 btrfs: fix misleading variable name for flags
The variable was named 'data' in btrfs_reserve_extent and that's the
only function that actually uses it to let btrfs_get_alloc_profile know
what profile we want. Then it's passed down as u64 flags.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06 15:55:27 -04:00
Eric Sandeen
48a3b6366f btrfs: make static code static & remove dead code
Big patch, but all it does is add statics to functions which
are in fact static, then remove the associated dead-code fallout.

removed functions:

btrfs_iref_to_path()
__btrfs_lookup_delayed_deletion_item()
__btrfs_search_delayed_insertion_item()
__btrfs_search_delayed_deletion_item()
find_eb_for_page()
btrfs_find_block_group()
range_straddles_pages()
extent_range_uptodate()
btrfs_file_extent_length()
btrfs_scrub_cancel_devid()
btrfs_start_transaction_lflush()

btrfs_print_tree() is left because it is used for debugging.
btrfs_start_transaction_lflush() and btrfs_reada_detach() are
left for symmetry.

ulist.c functions are left, another patch will take care of those.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06 15:55:23 -04:00
Jan Schmidt
2f2320360b Btrfs: rescan for qgroups
If qgroup tracking is out of sync, a rescan operation can be started. It
iterates the complete extent tree and recalculates all qgroup tracking data.
This is an expensive operation and should not be used unless required.

A filesystem under rescan can still be umounted. The rescan continues on the
next mount.  Status information is provided with a separate ioctl while a
rescan operation is in progress.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06 15:55:19 -04:00
Jan Schmidt
fc36ed7e0b Btrfs: separate sequence numbers for delayed ref tracking and tree mod log
Sequence numbers for delayed refs have been introduced in the first version
of the qgroup patch set. To solve the problem of find_all_roots on a busy
file system, the tree mod log was introduced. The sequence numbers for that
were simply shared between those two users.

However, at one point in qgroup's quota accounting, there's a statement
accessing the previous sequence number, that's still just doing (seq - 1)
just as it would have to in the very first version.

To satisfy that requirement, this patch makes the sequence number counter 64
bit and splits it into a major part (used for qgroup sequence number
counting) and a minor part (incremented for each tree modification in the
log). This enables us to go exactly one major step backwards, as required
for qgroups, while still incrementing the sequence counter for tree mod log
insertions to keep track of their order. Keeping them in a single variable
means there's no need to change all the code dealing with comparisons of two
sequence numbers.

The sequence number is reset to 0 on commit (not new in this patch), which
ensures we won't overflow the two 32 bit counters.

Without this fix, the qgroup tracking can occasionally go wrong and WARN_ONs
from the tree mod log code may happen.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06 15:55:17 -04:00
Stefan Behrens
5fbf83c10c Btrfs: delete unused parameter to btrfs_read_root_item()
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06 15:55:14 -04:00
Tsutomu Itoh
4b90c68015 Btrfs: remove unused argument of btrfs_extend_item()
Argument 'trans' is not used in btrfs_extend_item().

Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06 15:54:53 -04:00
Tsutomu Itoh
afe5fea72b Btrfs: cleanup of function where fixup_low_keys() is called
If argument 'trans' is unnecessary in the function where
fixup_low_keys() is called, 'trans' is deleted.

Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06 15:54:52 -04:00
Miao Xie
ceda086424 Btrfs: use a lock to protect incompat/compat flag of the super block
The following case will make the incompat/compat flag of the super block
be recovered.
 Task1					|Task2
 flags = btrfs_super_incompat_flags();	|
					|flags = btrfs_super_incompat_flags();
 flags |= new_flag1;			|
					|flags |= new_flag2;
 btrfs_set_super_incompat_flags(flags);	|
					|btrfs_set_super_incompat_flags(flags);
the new_flag1 is recovered.

In order to avoid this problem, we introduce a lock named super_lock into
the btrfs_fs_info structure. If we want to update incompat/compat flags
of the super block, we must hold it.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06 15:54:46 -04:00
Wang Shilong
f2f6ed3d54 Btrfs: introduce a mutex lock for btrfs quota operations
The original code has one spin_lock 'qgroup_lock' to protect quota
configurations in memory. If we want to add a BTRFS_QGROUP_INFO_KEY,
it will be added to Btree firstly, and then update configurations in
memory,however, a race condition may happen between these operations.
For example:
	->add_qgroup_info_item()
		->add_qgroup_rb()

For the above case, del_qgroup_info_item() may happen just before
add_qgroup_rb().

What's worse, when we want to add a qgroup relation:
	->add_qgroup_relation_item()
		->add_qgroup_relations()

We don't have any checks whether 'src' and 'dst' exist before
add_qgroup_relation_item(), a race condition can also happen for
the above case.

To avoid race condition and have all the necessary checks, we introduce
a mutex lock 'qgroup_ioctl_lock', and we make all the user change operations
protected by the mutex lock.

Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06 15:54:38 -04:00
Josef Bacik
09a2a8f96e Btrfs: fix bad extent logging
A user sent me a btrfs-image of a file system that was panicing on mount during
the log recovery.  I had originally thought these problems were from a bug in
the free space cache code, but that was just a symptom of the problem.  The
problem is if your application does something like this

[prealloc][prealloc][prealloc]

the internal extent maps will merge those all together into one extent map, even
though on disk they are 3 separate extents.  So if you go to write into one of
these ranges the extent map will be right since we use the physical extent when
doing the write, but when we log the extents they will use the wrong sizes for
the remainder prealloc space.  If this doesn't happen to trip up the free space
cache (which it won't in a lot of cases) then you will get bogus entries in your
extent tree which will screw stuff up later.  The data and such will still work,
but everything else is broken.  This patch fixes this by not allowing extents
that are on the modified list to be merged.  This has the side effect that we
are no longer adding everything to the modified list all the time, which means
we now have to call btrfs_drop_extents every time we log an extent into the
tree.  So this allows me to drop all this speciality code I was using to get
around calling btrfs_drop_extents.  With this patch the testcase I've created no
longer creates a bogus file system after replaying the log.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06 15:54:34 -04:00
Simon Kirby
c2cf52eb71 Btrfs: Include the device in most error printk()s
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: Simon Kirby <sim@hostway.ca>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06 15:54:23 -04:00
Josef Bacik
3173a18f70 Btrfs: add a incompatible format change for smaller metadata extent refs
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: Josef Bacik <jbacik@fusionio.com>
2013-05-06 15:54:18 -04:00
David Sterba
087488109a btrfs: clean up transaction abort messages
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: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06 15:52:56 -04:00
Miao Xie
d5c1207017 Btrfs: fix wrong reserved space in qgroup during snap/subv creation
There are two problems in the space reservation of the snapshot/
subvolume creation.
- don't reserve the space for the root item insertion
- the space which is reserved in the qgroup is different with
  the free space reservation. we need reserve free space for
  7 items, but in qgroup reservation, we need reserve space only
  for 3 items.

So we implement new metadata reservation functions for the
snapshot/subvolume creation.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-28 13:33:54 -05:00
Miao Xie
dc81cdc58a Btrfs: fix remount vs autodefrag
If we remount the fs to close the auto defragment or make the fs R/O,
we should stop the auto defragment.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-02-21 08:11:43 -05:00
Chris Mason
e942f883bc Merge branch 'raid56-experimental' into for-linus-3.9
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

Conflicts:
	fs/btrfs/ctree.h
	fs/btrfs/extent-tree.c
	fs/btrfs/inode.c
	fs/btrfs/volumes.c
2013-02-20 14:06:05 -05:00
Zach Brown
cdb4c5748c btrfs: define BTRFS_MAGIC as a u64 value
super.magic is an le64 but it's treated as an unterminated string when
compared against BTRFS_MAGIC which is defined as a string.  Instead
define BTRFS_MAGIC as a normal hex value and use endian helpers to
compare it to the super's magic.

I tested this by mounting an fs made before the change and made sure
that it didn't introduce sparse errors.  This matches a similar cleanup
that is pending in btrfs-progs.  David Sterba pointed out that we should
fix the kernel side as well :).

Signed-off-by: Zach Brown <zab@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20 13:00:01 -05:00
Josef Bacik
569e0f358c Btrfs: place ordered operations on a per transaction list
Miao made the ordered operations stuff run async, which introduced a
deadlock where we could get somebody (sync) racing in and committing the
transaction while a commit was already happening.  The new committer would
try and flush ordered operations which would hang waiting for the commit to
finish because it is done asynchronously and no longer inherits the callers
trans handle.  To fix this we need to make the ordered operations list a per
transaction list.  We can get new inodes added to the ordered operation list
by truncating them and then having another process writing to them, so this
makes it so that anybody trying to add an ordered operation _must_ start a
transaction in order to add itself to the list, which will keep new inodes
from getting added to the ordered operations list after we start committing.
This should fix the deadlock and also keeps us from doing a lot more work
than we need to during commit.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20 12:59:57 -05:00
David Sterba
210549ebe9 btrfs: add cancellation points to defrag
The defrag operation can take very long, we want to have a way how to
cancel it. The code checks for a pending signal at safe points in the
defrag loops and returns EAGAIN. This means a user can press ^C after
running 'btrfs fi defrag', woks for both defrag modes, files and root.

Returning from the command was instant in my light tests, but may take
longer depending on the aging factor of the filesystem.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20 12:59:51 -05:00
Josef Bacik
5d80366e9b Btrfs: steal from global reserve if we are cleaning up orphans
Sometimes xfstest 83 will fail to remount the scratch device because we've
gotten ourselves so full that we cannot cleanup the orphan items.  In this
case check to see if we're doing the orphan cleanup and if we are allow us
to steal our reservation from the global block rsv.  With this patch I've
not been able to reproduce the failed mount problem.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20 12:59:42 -05:00
Eric Sandeen
de78b51a28 btrfs: remove cache only arguments from defrag path
The entry point at the defrag ioctl always sets "cache only" to 0;
the codepaths haven't run for a long time as far as I can
tell.  Chris says they're dead code, so remove them.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20 12:59:36 -05:00
Eric Sandeen
aa43a17c21 btrfs: handle null fs_info in btrfs_panic()
At least backref_tree_panic() can apparently pass
in a null fs_info, so handle that in __btrfs_panic
to get the message out on the console.

The btrfs_panic macro also uses fs_info, but that's
largely pointless; it's testing to see if
BTRFS_MOUNT_PANIC_ON_FATAL_ERROR is not set.
But if it *were* set, __btrfs_panic() would have,
well, paniced and we wouldn't be here, testing it!
So just BUG() at this point.

And since we only use fs_info once now, just use it
directly.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20 12:59:18 -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
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
Miao Xie
c018daecea Btrfs: protect fs_info->alloc_start
fs_info->alloc_start is a 64bits variant, can be accessed by
multi-task, but it is not protected strictly, it can be changed
while we are accessing it. On 32bit machine, we will get wrong
value because we access it by two instructions.(In fact, it is
also possible that the same problem happens on the 64bit machine,
because the compiler may split the 64bit operation into two 32bit
operation.)

For example:
Assuming -> alloc_start is 0x0000 0000 0001 0000 at the beginning,
then we remount and set ->alloc_start to 0x0000 0100 0000 0000.
	Task0 			Task1
				load high 32 bits
	set high 32 bits
	set low 32 bits
				load low 32 bits

Task1 will get 0.

This patch fixes this problem by using two locks to protect it
	fs_info->chunk_mutex
	sb->s_umount
On the read side, we just need get one of these two locks, and on
the write side, we must lock all of them.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20 12:59:02 -05:00
Miao Xie
8c6a3ee6db Btrfs: add a comment for fs_info->max_inline
Though ->max_inline is a 64bit variant, and may be accessed by
multi-task, but it is just suggestive number, so we needn't add
anything to protect fs_info->max_inline, just add a comment to
explain wny we don't use a lock to protect it.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20 12:59:01 -05:00
Filipe Brandenburger
55e301fd57 Btrfs: move fs/btrfs/ioctl.h to include/uapi/linux/btrfs.h
The header file will then be installed under /usr/include/linux so that
userspace applications can refer to Btrfs ioctls by name and use the same
structs used internally in the kernel.

Signed-off-by: Filipe Brandenburger <filbranden@google.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20 09:37:28 -05:00
Miao Xie
e6ec716f0d Btrfs: make raid attr array more readable
The current code of raid attr arry is hard to understand and it is easy to
introduce some problem if we modify the array. So I changed it and made it
more readable.

Cc: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20 09:37:19 -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
Liu Bo
dcfac4156f Btrfs: kill unused argument of btrfs_pin_extent_for_log_replay
Argument 'trans' is not used any more.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20 09:37:14 -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
Chris Mason
4ae10b3a13 Btrfs: Add a stripe cache to raid56
The stripe cache allows us to avoid extra read/modify/write cycles
by caching the pages we read off the disk.  Pages are cached when:

* They are read in during a read/modify/write cycle

* They are written during a read/modify/write cycle

* They are involved in a parity rebuild

Pages are not cached if we're doing a full stripe write.  We're
assuming that a full stripe write won't be followed by another
partial stripe write any time soon.

This provides a substantial boost in performance for workloads that
synchronously modify adjacent offsets in the file, and for the parity
rebuild use case in general.

The size of the stripe cache isn't tunable (yet) and is set at 1024
entries.

Example on flash: dd if=/dev/zero of=/mnt/xxx bs=4K oflag=direct

Without the stripe cache  -- 2.1MB/s
With the stripe cache 21MB/s

Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-02-01 14:24:23 -05:00
David Woodhouse
53b381b3ab Btrfs: RAID5 and RAID6
This builds on David Woodhouse's original Btrfs raid5/6 implementation.
The code has changed quite a bit, blame Chris Mason for any bugs.

Read/modify/write is done after the higher levels of the filesystem have
prepared a given bio.  This means the higher layers are not responsible
for building full stripes, and they don't need to query for the topology
of the extents that may get allocated during delayed allocation runs.
It also means different files can easily share the same stripe.

But, it does expose us to incorrect parity if we crash or lose power
while doing a read/modify/write cycle.  This will be addressed in a
later commit.

Scrub is unable to repair crc errors on raid5/6 chunks.

Discard does not work on raid5/6 (yet)

The stripe size is fixed at 64KiB per disk.  This will be tunable
in a later commit.

Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-02-01 14:24:23 -05:00
David Woodhouse
64a167011b Btrfs: add rw argument to merge_bio_hook()
We'll want to merge writes so they can fill a full RAID[56] stripe, but
not necessarily reads.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-02-01 11:49:47 -05:00
Chris Mason
9c52057c69 Btrfs: fix hash overflow handling
The handling for directory crc hash overflows was fairly obscure,
split_leaf returns EOVERFLOW when we try to extend the item and that is
supposed to bubble up to userland.  For a while it did so, but along the
way we added better handling of errors and forced the FS readonly if we
hit IO errors during the directory insertion.

Along the way, we started testing only for EEXIST and the EOVERFLOW case
was dropped.  The end result is that we may force the FS readonly if we
catch a directory hash bucket overflow.

This fixes a few problem spots.  First I add tests for EOVERFLOW in the
places where we can safely just return the error up the chain.

btrfs_rename is harder though, because it tries to insert the new
directory item only after it has already unlinked anything the rename
was going to overwrite.  Rather than adding very complex logic, I added
a helper to test for the hash overflow case early while it is still safe
to bail out.

Snapshot and subvolume creation had a similar problem, so they are using
the new helper now too.

Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Reported-by: Pascal Junod <pascal@junod.info>
2012-12-17 14:48:21 -05:00
Liu Bo
31e502298d Btrfs: put raid properties into global table
Raid properties can be shared among raid calculation code, we can put
them into a global table to keep it simple.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:28 -05:00
Josef Bacik
ad91455969 Btrfs: don't memset new tokens
Our token logic depends on token->kaddr being set, and if it is not it sets
everything properly as needed.  So instead of memsetting just set
token->kaddr to NULL.  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
70c8a91ce2 Btrfs: log changed inodes based on the extent map tree
We don't really need to copy extents from the source tree since we have all
of the information already available to us in the extent_map tree.  So
instead just write the extents straight to the log tree and don't bother to
copy the extent items from the source tree.

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:24 -05:00
Josef Bacik
d6393786cd Btrfs: add path->really_keep_locks
You'd think path->keep_locks would keep all the locks wouldn't you?  You'd
be wrong.  It only keeps them if the slot is pointing to the last item in
the node.  This is for use with btrfs_next_leaf, which needs this sort of
thing.  But the horrible horrible things I'm going to do to the tree log
means I really need everything held from root to leaf so I can add and
delete items in the same search.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:24 -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
Miao Xie
9247f3170b Btrfs: use slabs for auto defrag allocation
The auto defrag 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>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:11 -05:00
Stefan Behrens
72d7aefccd Btrfs: increase BTRFS_MAX_MIRRORS by one for dev replace
This change of the define is effective in all modes, it
is required and used only in the case when a device replace
procedure is running. The reason is that during an active
device replace procedure, the target device of the copy
operation is a mirror for the filesystem data as well that
can be used to read data in order to repair read errors on
other disks.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12 17:15:44 -05:00
Stefan Behrens
29a8d9a0bc Btrfs: introduce GET_READ_MIRRORS functionality for btrfs_map_block()
Before this commit, btrfs_map_block() was called with REQ_WRITE
in order to retrieve the list of mirrors for a disk block.
This needs to be changed for the device replace procedure since
it makes a difference whether you are asking for read mirrors
or for locations to write to.
GET_READ_MIRRORS is introduced as a new interface to call
btrfs_map_block().
In the current commit, the functionality is not yet changed,
only the interface for GET_READ_MIRRORS is introduced and all
the places that should use this new interface are adapted.

The reason that REQ_WRITE cannot be abused anymore to retrieve
a list of read mirrors is that during a running dev replace
operation all write requests to the live filesystem are
duplicated to also write to the target drive.
Keep in mind that the target disk is only partially a valid
copy of the source disk while the operation is ongoing. All
writes go to the target disk, but not all reads would return
valid data on the target disk. Therefore it is not possible
anymore to abuse a REQ_WRITE interface to find valid mirrors
for a REQ_READ.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12 17:15:43 -05:00
Stefan Behrens
e93c89c1aa Btrfs: add new sources for device replace code
This adds a new file to the sources together with the header file
and the changes to ioctl.h and ctree.h that are required by the
new C source file. Additionally, 4 new functions are added to
volume.c that deal with device creation and destruction.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12 17:15:41 -05:00
Stefan Behrens
ff023aac31 Btrfs: add code to scrub to copy read data to another disk
The device replace procedure makes use of the scrub code. The scrub
code is the most efficient code to read the allocated data of a disk,
i.e. it reads sequentially in order to avoid disk head movements, it
skips unallocated blocks, it uses read ahead mechanisms, and it
contains all the code to detect and repair defects.
This commit adds code to scrub to allow the scrub code to copy read
data to another disk.
One goal is to be able to perform as fast as possible. Therefore the
write requests are collected until huge bios are built, and the
write process is decoupled from the read process with some kind of
flow control, of course, in order to limit the allocated memory.
The best performance on spinning disks could by reached when the
head movements are avoided as much as possible. Therefore a single
worker is used to interface the read process with the write process.
The regular scrub operation works as fast as before, it is not
negatively influenced and actually it is more or less unchanged.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12 17:15:41 -05:00
Stefan Behrens
63a212abc2 Btrfs: disallow some operations on the device replace target device
This patch adds some code to disallow operations on the device that
is used as the target for the device replace operation.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12 17:15:39 -05:00
Stefan Behrens
5ac00addc7 Btrfs: disallow mutually exclusive admin operations from user mode
Btrfs admin operations that are manually started from user mode
and that cannot be executed at the same time return -EINPROGRESS.
A common way to enter and leave this locked section is introduced
since it used to be specific to the balance operation.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12 17:15:38 -05:00
Stefan Behrens
a2bff64025 Btrfs: introduce a btrfs_dev_replace_item type
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12 17:15:38 -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
Miao Xie
315a9850da Btrfs: fix wrong file extent length
There are two types of the file extent - inline extent and regular extent,
When we log file extents, we didn't take inline extent into account, fix it.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12 17:15:21 -05:00
Masanari Iida
d142324873 Btrfs: Fix typo in fs/btrfs
Correct spelling typo in btrfs.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12 17:15:17 -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
Miao Xie
08e007d2e5 Btrfs: improve the noflush reservation
In some places(such as: evicting inode), we just can not flush the reserved
space of delalloc, flushing the delayed directory index and delayed inode
is OK, but we don't try to flush those things and just go back when there is
no enough space to be reserved. This patch fixes this problem.

We defined 3 types of the flush operations: NO_FLUSH, FLUSH_LIMIT and FLUSH_ALL.
If we can in the transaction, we should not flush anything, or the deadlock
would happen, so use NO_FLUSH. If we flushing the reserved space of delalloc
would cause deadlock, use FLUSH_LIMIT. In the other cases, FLUSH_ALL is used,
and we will flush all things.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-11 13:31:31 -05:00
Linus Torvalds
f48d42773b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "This has our series of fixes for the next rc.  The biggest batch is
  from Jan Schmidt, fixing up some problems in our subvolume quota code
  and fixing btrfs send/receive to work with the new extended inode
  refs."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: do not bug when we fail to commit the transaction
  Btrfs: fix memory leak when cloning root's node
  Btrfs: Use btrfs_update_inode_fallback when creating a snapshot
  Btrfs: Send: preserve ownership (uid and gid) also for symlinks.
  Btrfs: fix deadlock caused by the nested chunk allocation
  btrfs: Return EINVAL when length to trim is less than FSB
  Btrfs: fix memory leak in btrfs_quota_enable()
  Btrfs: send correct rdev and mode in btrfs-send
  Btrfs: extended inode refs support for send mechanism
  Btrfs: Fix wrong error handling code
  Fix a sign bug causing invalid memory access in the ino_paths ioctl.
  Btrfs: comment for loop in tree_mod_log_insert_move
  Btrfs: fix extent buffer reference for tree mod log roots
  Btrfs: determine level of old roots
  Btrfs: tree mod log's old roots could still be part of the tree
  Btrfs: fix a tree mod logging issue for root replacement operations
  Btrfs: don't put removals from push_node_left into tree mod log twice
2012-10-26 09:34:04 -07:00
Chris Mason
c657c3ef1a Merge branch 'for-chris-fixed' of git://git.jan-o-sch.net/btrfs-unstable 2012-10-25 15:53:10 -04:00
Josef Bacik
be6aef6049 Btrfs: Use btrfs_update_inode_fallback when creating a snapshot
On a really full file system I was getting ENOSPC back from
btrfs_update_inode when trying to update the parent inode when creating a
snapshot.  Just use the fallback method so we can update the inode and not
have to worry about having a delayed ref.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-10-25 15:50:18 -04:00
Jan Schmidt
5b6602e762 Btrfs: determine level of old roots
In btrfs_find_all_roots' termination condition, we compare the level of the
old buffer we got from btrfs_search_old_slot to the level of the current
root node. We'd better compare it to the level of the rewinded root node.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-10-24 12:36:38 +02:00
Linus Torvalds
72055425e5 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs update from Chris Mason:
 "This is a large pull, with the bulk of the updates coming from:

   - Hole punching

   - send/receive fixes

   - fsync performance

   - Disk format extension allowing more hardlinks inside a single
     directory (btrfs-progs patch required to enable the compat bit for
     this one)

  I'm cooking more unrelated RAID code, but I wanted to make sure this
  original batch makes it in.  The largest updates here are relatively
  old and have been in testing for some time."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (121 commits)
  btrfs: init ref_index to zero in add_inode_ref
  Btrfs: remove repeated eb->pages check in, disk-io.c/csum_dirty_buffer
  Btrfs: fix page leakage
  Btrfs: do not warn_on when we cannot alloc a page for an extent buffer
  Btrfs: don't bug on enomem in readpage
  Btrfs: cleanup pages properly when ENOMEM in compression
  Btrfs: make filesystem read-only when submitting barrier fails
  Btrfs: detect corrupted filesystem after write I/O errors
  Btrfs: make compress and nodatacow mount options mutually exclusive
  btrfs: fix message printing
  Btrfs: don't bother committing delayed inode updates when fsyncing
  btrfs: move inline function code to header file
  Btrfs: remove unnecessary IS_ERR in bio_readpage_error()
  btrfs: remove unused function btrfs_insert_some_items()
  Btrfs: don't commit instead of overcommitting
  Btrfs: confirmation of value is added before trace_btrfs_get_extent() is called
  Btrfs: be smarter about dropping things from the tree log
  Btrfs: don't lookup csums for prealloc extents
  Btrfs: cache extent state when writing out dirty metadata pages
  Btrfs: do not hold the file extent leaf locked when adding extent item
  ...
2012-10-10 10:49:20 +09:00
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
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
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
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
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
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
Josef Bacik
7014cdb493 Btrfs: btrfs_drop_extent_cache should never fail
I noticed this when I was doing the fsync stuff, we allocate split extents if we
drop an extent range that is in the middle of an existing extent.  This BUG()'s
if we fail to allocate memory, but the fact is this is just a cache, we will
just regenerate the cache if we need it, the important part is that we free the
range we are given.  This can be done without allocations, so if we fail to
allocate splits just skip the splitting stage and free our em and look for more
extents to drop.  This also makes btrfs_drop_extent_cache a void since nobody
was checking the return value anyway.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-10-01 15:19:09 -04:00
Josef Bacik
2aaa665581 Btrfs: add hole punching
This patch adds hole punching via fallocate.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-10-01 15:19:07 -04:00
Josef Bacik
2671485d39 Btrfs: remove unused hint byte argument for btrfs_drop_extents
I audited all users of btrfs_drop_extents and found that nobody actually uses
the hint_byte argument.  I'm sure it was used for something at some point but
it's not used now, and the way the pinning works the disk bytenr would never be
immediately useful anyway so lets just remove it.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-10-01 15:19:06 -04:00
Josef Bacik
ca7e70f590 Btrfs: do not needlessly restart the transaction for enospc
We will stop and restart a transaction every time we move to a different leaf
when truncating a file.  This is for enospc reasons, but really we could
probably get away with doing this a little better by actually working until we
hit an ENOSPC.  So add a ->failfast flag to the block_rsv and set it when we do
truncates which will fail as soon as the block rsv runs out of space, and then
at that point we can stop and restart the transaction and refill the block rsv
and carry on.  This will make rm'ing of a file with lots of extents a bit
faster.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-10-01 15:19:04 -04:00
Josef Bacik
5dc562c541 Btrfs: turbo charge fsync
At least for the vm workload.  Currently on fsync we will

1) Truncate all items in the log tree for the given inode if they exist

and

2) Copy all items for a given inode into the log

The problem with this is that for things like VMs you can have lots of
extents from the fragmented writing behavior, and worst yet you may have
only modified a few extents, not the entire thing.  This patch fixes this
problem by tracking which transid modified our extent, and then when we do
the tree logging we find all of the extents we've modified in our current
transaction, sort them and commit them.  We also only truncate up to the
xattrs of the inode and copy that stuff in normally, and then just drop any
extents in the range we have that exist in the log already.  Here are some
numbers of a 50 meg fio job that does random writes and fsync()s after every
write

		Original	Patched
SATA drive	82KB/s		140KB/s
Fusion drive	431KB/s		2532KB/s

So around 2-6 times faster depending on your hardware.  There are a few
corner cases, for example if you truncate at all we have to do it the old
way since there is no way to be sure what is in the log is ok.  This
probably could be done smarter, but if you write-fsync-truncate-write-fsync
you deserve what you get.  All this work is in RAM of course so if your
inode gets evicted from cache and you read it in and fsync it we'll do it
the slow way if we are still in the same transaction that we last modified
the inode in.

The biggest cool part of this is that it requires no changes to the recovery
code, so if you fsync with this patch and crash and load an old kernel, it
will run the recovery and be a-ok.  I have tested this pretty thoroughly
with an fsync tester and everything comes back fine, as well as xfstests.
Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-10-01 15:19:03 -04:00
Linus Torvalds
99dbb1632f Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull the trivial tree from Jiri Kosina:
 "Tiny usual fixes all over the place"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (34 commits)
  doc: fix old config name of kprobetrace
  fs/fs-writeback.c: cleanup riteback_sb_inodes kerneldoc
  btrfs: fix the commment for the action flags in delayed-ref.h
  btrfs: fix trivial typo for the comment of BTRFS_FREE_INO_OBJECTID
  vfs: fix kerneldoc for generic_fh_to_parent()
  treewide: fix comment/printk/variable typos
  ipr: fix small coding style issues
  doc: fix broken utf8 encoding
  nfs: comment fix
  platform/x86: fix asus_laptop.wled_type module parameter
  mfd: printk/comment fixes
  doc: getdelays.c: remember to close() socket on error in create_nl_socket()
  doc: aliasing-test: close fd on write error
  mmc: fix comment typos
  dma: fix comments
  spi: fix comment/printk typos in spi
  Coccinelle: fix typo in memdup_user.cocci
  tmiofb: missing NULL pointer checks
  tools: perf: Fix typo in tools/perf
  tools/testing: fix comment / output typos
  ...
2012-10-01 09:06:36 -07:00
Wang Sheng-Hui
527a136138 btrfs: fix trivial typo for the comment of BTRFS_FREE_INO_OBJECTID
It should be storing, not sotring.

Signed-off-by: Wang Sheng-Hui <shhuiw@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-09-06 11:11:14 +02:00
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
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
Josef Bacik
c329861da4 Btrfs: don't allocate a seperate csums array for direct reads
We've been allocating a big array for csums instead of storing them in the
io_tree like we do for buffered reads because previously we were locking the
entire range, so we didn't have an extent state for each sector of the
range.  But now that we do the range locking as we map the buffers we can
limit the mapping lenght to sectorsize and use the private part of the
io_tree for our csums.  This allows us to avoid an extra memory allocation
for direct reads which could incur latency.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2012-08-28 16:53:30 -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
7069830a9e Btrfs: add btrfs_compare_trees function
This function is used to find the differences between
two trees. The tree compare skips whole subtrees if it
detects shared tree blocks and thus is pretty fast.

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 23:30:14 +02:00
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
Mitch Harder
2b0ce2c290 Btrfs: Check INCOMPAT flags on remount and add helper function
In support of the recently added capability to remount with lzo
compression, provide a helper function to check the compression
INCOMPAT flags when remounting with lzo compression, and set
the flags if necessary.

Also, implement the new helper function when defragmenting with
explicit lzo compression and when setting the default subvolume.

Signed-off-by: Mitch Harder <mitch.harder@sabayonlinux.org>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-07-25 16:14:31 -04:00
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
Arne Jansen
e679376911 Btrfs: add helper for tree enumeration
Often no exact match is wanted but just the next lower or
higher item. There's a lot of duplicated code throughout
btrfs to deal with the corner cases. This patch adds a
helper function that can facilitate searching.

Signed-off-by: Arne Jansen <sensille@gmx.net>
2012-07-25 17:33:18 +02:00
Li Zefan
18077bb413 Btrfs: rewrite BTRFS_SETGET_FUNCS
BTRFS_SETGET_FUNCS macro is used to generate btrfs_set_foo() and
btrfs_foo() functions, which read and write specific fields in the
extent buffer.

The total number of set/get functions is ~200, but in fact we only
need 8 functions: 2 for u8 field, 2 for u16, 2 for u32 and 2 for u64.

It results in redunction of ~37K bytes.

   text    data     bss     dec     hex filename
 629661   12489     216  642366   9cd3e fs/btrfs/btrfs.o.orig
 592637   12489     216  605342   93c9e fs/btrfs/btrfs.o

Signed-off-by: Li Zefan <lizefan@huawei.com>
2012-07-23 16:28:06 -04:00
Li Zefan
b4d7c3c945 Btrfs: kill free_space pointer from inode structure
Inodes always allocate free space with BTRFS_BLOCK_GROUP_DATA type,
which means every inode has the same BTRFS_I(inode)->free_space pointer.

This shrinks struct btrfs_inode by 4 bytes (or 8 bytes on 64 bits).

Signed-off-by: Li Zefan <lizefan@huawei.com>
2012-07-23 16:28:05 -04:00
Arne Jansen
bcef60f249 Btrfs: quota tree support and startup
Init the quota tree along with the others on open_ctree
and close_ctree. Add the quota tree to the list of well
known trees in btrfs_read_fs_root_no_name.

Signed-off-by: Arne Jansen <sensille@gmx.net>
2012-07-12 10:54:38 +02:00
Arne Jansen
bed92eae26 Btrfs: qgroup implementation and prototypes
Signed-off-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-07-12 10:54:21 +02:00
Arne Jansen
416ac51da9 Btrfs: qgroup state and initialization
Add state to fs_info.

Signed-off-by: Arne Jansen <sensille@gmx.net>
2012-07-10 15:14:44 +02:00
Arne Jansen
2f38b3e190 Btrfs: add helper for tree enumeration
Often no exact match is wanted but just the next lower or
higher item. There's a lot of duplicated code throughout
btrfs to deal with the corner cases. This patch adds a
helper function that can facilitate searching.

Signed-off-by: Arne Jansen <sensille@gmx.net>
2012-07-10 15:14:42 +02:00
Arne Jansen
630dc772ea Btrfs: qgroup on-disk format
Not all features are in use by the current version
and thus may change in the future.

Signed-off-by: Arne Jansen <sensille@gmx.net>
2012-07-10 15:14:42 +02:00
Jan Schmidt
097b8a7c9e Btrfs: join tree mod log code with the code holding back delayed refs
We've got two mechanisms both required for reliable backref resolving (tree
mod log and holding back delayed refs). You cannot make use of one without
the other. So instead of requiring the user of this mechanism to setup both
correctly, we join them into a single interface.

Additionally, we stop inserting non-blockers into fs_info->tree_mod_seq_list
as we did before, which was of no value.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-07-10 15:14:41 +02:00
Linus Torvalds
8874e812fe Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "This is a small pull with btrfs fixes.  The biggest of the bunch is
  another fix for the new backref walking code.

  We're still hammering out one btrfs dio vs buffered reads problem, but
  that one will have to wait for the next rc."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: delay iput with async extents
  Btrfs: add a missing spin_lock
  Btrfs: don't assume to be on the correct extent in add_all_parents
  Btrfs: introduce btrfs_next_old_item
2012-06-21 13:41:07 -07:00
Alexander Block
1c8f52a5e9 Btrfs: introduce btrfs_next_old_item
We introduce btrfs_next_old_item that uses btrfs_next_old_leaf instead
of btrfs_next_leaf.

btrfs_next_item is also changed to simply call btrfs_next_old_item with
time_seq being 0.

Signed-off-by: Alexander Block <ablock84@googlemail.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-06-21 07:19:34 -04:00
Linus Torvalds
718f58ad61 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs update from Chris Mason:
 "The dates look like I had to rebase this morning because there was a
  compiler warning for a printk arg that I had missed earlier.

  These are all fixes, including one to prevent using stale pointers for
  device names, and lots of fixes around transaction abort cleanups
  (Josef, Liu Bo).

  Jan Schmidt also sent in a number of fixes for the new reference
  number tracking code.

  Liu Bo beat me to updating the MAINTAINERS file.  Since he thought to
  also fix the git url, I kept his commit."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (24 commits)
  Btrfs: update MAINTAINERS info for BTRFS FILE SYSTEM
  Btrfs: destroy the items of the delayed inodes in error handling routine
  Btrfs: make sure that we've made everything in pinned tree clean
  Btrfs: avoid memory leak of extent state in error handling routine
  Btrfs: do not resize a seeding device
  Btrfs: fix missing inherited flag in rename
  Btrfs: fix incompat flags setting
  Btrfs: fix defrag regression
  Btrfs: call filemap_fdatawrite twice for compression
  Btrfs: keep inode pinned when compressing writes
  Btrfs: implement ->show_devname
  Btrfs: use rcu to protect device->name
  Btrfs: unlock everything properly in the error case for nocow
  Btrfs: fix btrfs_destroy_marked_extents
  Btrfs: abort the transaction if the commit fails
  Btrfs: wake up transaction waiters when aborting a transaction
  Btrfs: fix locking in btrfs_destroy_delayed_refs
  Btrfs: pass locked_page into extent_clear_unlock_delalloc if theres an error
  Btrfs: fix race in tree mod log addition
  Btrfs: add btrfs_next_old_leaf
  ...
2012-06-15 16:04:37 -07:00
Jan Schmidt
3d7806eca4 Btrfs: add btrfs_next_old_leaf
To make sense of the tree mod log, the backref walker not only needs
btrfs_search_old_slot, but it also called btrfs_next_leaf, which in turn was
calling btrfs_search_slot. This obviously didn't give the correct result.

This commit adds btrfs_next_old_leaf, a drop-in replacement for
btrfs_next_leaf with a time_seq parameter. If it is zero, it behaves exactly
like btrfs_next_leaf. If it is non-zero, it will use btrfs_search_old_slot
with this time_seq parameter.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-06-14 18:52:09 +02:00
Linus Torvalds
1193755ac6 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs changes from Al Viro.
 "A lot of misc stuff.  The obvious groups:
   * Miklos' atomic_open series; kills the damn abuse of
     ->d_revalidate() by NFS, which was the major stumbling block for
     all work in that area.
   * ripping security_file_mmap() and dealing with deadlocks in the
     area; sanitizing the neighborhood of vm_mmap()/vm_munmap() in
     general.
   * ->encode_fh() switched to saner API; insane fake dentry in
     mm/cleancache.c gone.
   * assorted annotations in fs (endianness, __user)
   * parts of Artem's ->s_dirty work (jff2 and reiserfs parts)
   * ->update_time() work from Josef.
   * other bits and pieces all over the place.

  Normally it would've been in two or three pull requests, but
  signal.git stuff had eaten a lot of time during this cycle ;-/"

Fix up trivial conflicts in Documentation/filesystems/vfs.txt (the
'truncate_range' inode method was removed by the VM changes, the VFS
update adds an 'update_time()' method), and in fs/btrfs/ulist.[ch] (due
to sparse fix added twice, with other changes nearby).

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (95 commits)
  nfs: don't open in ->d_revalidate
  vfs: retry last component if opening stale dentry
  vfs: nameidata_to_filp(): don't throw away file on error
  vfs: nameidata_to_filp(): inline __dentry_open()
  vfs: do_dentry_open(): don't put filp
  vfs: split __dentry_open()
  vfs: do_last() common post lookup
  vfs: do_last(): add audit_inode before open
  vfs: do_last(): only return EISDIR for O_CREAT
  vfs: do_last(): check LOOKUP_DIRECTORY
  vfs: do_last(): make ENOENT exit RCU safe
  vfs: make follow_link check RCU safe
  vfs: do_last(): use inode variable
  vfs: do_last(): inline walk_component()
  vfs: do_last(): make exit RCU safe
  vfs: split do_lookup()
  Btrfs: move over to use ->update_time
  fs: introduce inode operation ->update_time
  reiserfs: get rid of resierfs_sync_super
  reiserfs: mark the superblock as dirty a bit later
  ...
2012-06-01 10:34:35 -07:00
Josef Bacik
e41f941a23 Btrfs: move over to use ->update_time
Btrfs had been doing it's own file_update_time so we could catch ENOSPC
properly, so just update our btrfs_update_time to work with the new stuff and
then we'll be fancy later.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
2012-06-01 12:07:52 -04:00
Chris Mason
1e20932a23 Merge branch 'for-chris' of git://git.jan-o-sch.net/btrfs-unstable into for-linus
Conflicts:
	fs/btrfs/ulist.h

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-05-31 16:49:53 -04:00
Jan Schmidt
95a06077f7 Btrfs: use delayed ref sequence numbers for all fs-tree updates
The sequence number for delayed refs is needed to postpone certain delayed
refs for a very short period while walking backrefs. Before the tree
modification log, we thought we'd only have to hold back those references
that don't have a counter operation.

While now we've the tree mod log, we're rewinding fs tree blocks to a
defined consistent state. We cannot know in advance for which tree block
we'll be doing rewind operations later. Therefore, we must postpone all the
delayed refs for fs-tree blocks, even those having a counter operation.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-30 18:18:21 +02:00
Stefan Behrens
3d136a1131 Btrfs: set ioprio of scrub readahead to idle
Reduce ioprio class of scrub readahead threads to idle priority.
This setting is fixed. This priority has shown the best performance
during all measurements.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
2012-05-30 10:23:43 -04:00
Stefan Behrens
733f4fbbc1 Btrfs: read device stats on mount, write modified ones during commit
The device statistics are written into the device tree with each
transaction commit. Only modified statistics are written.
When a filesystem is mounted, the device statistics for each involved
device are read from the device tree and used to initialize the
counters.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
2012-05-30 10:23:41 -04:00
Josef Bacik
8a35d95ff4 Btrfs: fix how we deal with the orphan block rsv
Ceph was hitting this race where we would remove an inode from the per-root
orphan list before we would release the space we had reserved for the inode.
We actually don't need a list or anything, we just need to make sure the
root doesn't try to free up the orphan reserve until after the inodes have
released their reservations.  So use an atomic counter instead of a list on
the root and only decrement the counter after we've released our
reservation.  I've tested this as well as several others and we no longer
see the warnings that you would see while running ceph.  Thanks,
Btrfs: fix how we deal with the orphan block rsv

Ceph was hitting this race where we would remove an inode from the per-root
orphan list before we would release the space we had reserved for the inode.
We actually don't need a list or anything, we just need to make sure the
root doesn't try to free up the orphan reserve until after the inodes have
released their reservations.  So use an atomic counter instead of a list on
the root and only decrement the counter after we've released our
reservation.  I've tested this as well as several others and we no longer
see the warnings that you would see while running ceph.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
2012-05-30 10:23:37 -04:00
Jan Schmidt
5d9e75c41d Btrfs: add btrfs_search_old_slot
The tree modification log together with the current state of the tree gives
a consistent, old version of the tree. btrfs_search_old_slot is used to
search through this old version and return old (dummy!) extent buffers.
Naturally, this function cannot do any tree modifications.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-30 15:17:33 +02:00
Jan Schmidt
bd989ba359 Btrfs: add tree modification log functions
The tree mod log will log modifications made fs-tree nodes. Most
modifications are done by autobalance of the tree. Such changes are recorded
as long as a block entry exists. When released, the log is cleaned.

With the tree modification log, it's possible to reconstruct a consistent
old state of the tree. This is required to do backref walking on a busy
file system.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-30 15:17:01 +02:00
Jan Schmidt
f29021b29a Btrfs: add tree mod log to fs_info
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-26 12:17:54 +02:00
Jan Schmidt
64947ec0d1 Btrfs: move struct seq_list to ctree.h
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-26 12:17:53 +02:00
Jan Schmidt
5581a51a59 Btrfs: don't set for_cow parameter for tree block functions
Three callers of btrfs_free_tree_block or btrfs_alloc_tree_block passed
parameter for_cow = 1. In fact, these two functions should never mark
their tree modification operations as for_cow, because they can change
the number of blocks referenced by a tree.

Hence, we remove the extra for_cow parameter from these functions and
make them pass a zero down.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-05-26 12:17:53 +02:00
Linus Torvalds
f7b0069317 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "This has our collection of bug fixes.  I missed the last rc because I
  thought our patches were making NFS crash during my xfs test runs.
  Turns out it was an NFS client bug fixed by someone else while I tried
  to bisect it.

  All of these fixes are small, but some are fairly high impact.  The
  biggest are fixes for our mount -o remount handling, a deadlock due to
  GFP_KERNEL allocations in readdir, and a RAID10 error handling bug.

  This was tested against both 3.3 and Linus' master as of this morning."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (26 commits)
  Btrfs: reduce lock contention during extent insertion
  Btrfs: avoid deadlocks from GFP_KERNEL allocations during btrfs_real_readdir
  Btrfs: Fix space checking during fs resize
  Btrfs: fix block_rsv and space_info lock ordering
  Btrfs: Prevent root_list corruption
  Btrfs: fix repair code for RAID10
  Btrfs: do not start delalloc inodes during sync
  Btrfs: fix that check_int_data mount option was ignored
  Btrfs: don't count CRC or header errors twice while scrubbing
  Btrfs: fix btrfs_ioctl_dev_info() crash on missing device
  btrfs: don't return EINTR
  Btrfs: double unlock bug in error handling
  Btrfs: always store the mirror we read the eb from
  fs/btrfs/volumes.c: add missing free_fs_devices
  btrfs: fix early abort in 'remount'
  Btrfs: fix max chunk size check in chunk allocator
  Btrfs: add missing read locks in backref.c
  Btrfs: don't call free_extent_buffer twice in iterate_irefs
  Btrfs: Make free_ipath() deal gracefully with NULL pointers
  Btrfs: avoid possible use-after-free in clear_extent_bit()
  ...
2012-04-28 09:30:07 -07:00
Stefan Behrens
25cd999e1a Btrfs: fix that check_int_data mount option was ignored
The bitfield member mount_opt was too small by one bit to hold the mount
option that enabled to include data extents in the integrity checker.
Since the same issue happened when the BTRFS_MOUNT_PANIC_ON_FATAL_ERROR
option was added (git rebase silently merges so that the increase of the
size of the bitfield member is lost), the bit limit was removed entirely.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
2012-04-18 19:22:38 +02:00
Al Viro
6ed3cf2cdf btrfs: btrfs_root_readonly() broken on big-endian
->root_flags is __le64 and all accesses to it go through the helpers
that do proper conversions.  Except for btrfs_root_readonly(), which
checks bit 0 as in host-endian...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-04-13 11:54:32 -04:00
Chris Mason
1c691b330a Merge branch 'for-chris' of git://github.com/idryomov/btrfs-unstable into for-linus 2012-03-28 20:32:46 -04:00
Chris Mason
1d4284bd6e Merge branch 'error-handling' into for-linus
Conflicts:
	fs/btrfs/ctree.c
	fs/btrfs/disk-io.c
	fs/btrfs/extent-tree.c
	fs/btrfs/extent_io.c
	fs/btrfs/extent_io.h
	fs/btrfs/inode.c
	fs/btrfs/scrub.c

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-03-28 20:31:37 -04:00
Stefan Behrens
94598ba8d8 Btrfs: introduce common define for max number of mirrors
Readahead already has a define for the max number of mirrors. Scrub
needs such a define now, the rest of the code will need something
like this soon. Therefore the define was added to ctree.h and removed
from the readahead code.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-03-27 14:21:26 -04:00
Ilya Dryomov
0c460c0d70 Btrfs: move alloc_profile_is_valid() to volumes.c
Header file is not a good place to define functions.  This also moves a
call to alloc_profile_is_valid() down the stack and removes a redundant
check from __btrfs_alloc_chunk() - alloc_profile_is_valid() takes it
into account.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-03-27 17:09:17 +03:00
Ilya Dryomov
e8920a640b Btrfs: make profile_is_valid() check more strict
"0" is a valid value for an on-disk chunk profile, but it is not a valid
extended profile.  (We have a separate bit for single chunks in extended
case)

Also rename it to alloc_profile_is_valid() for clarity.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-03-27 17:09:17 +03:00
Ilya Dryomov
899c81eac8 Btrfs: add wrappers for working with alloc profiles
Add functions to abstract the conversion between chunk and extended
allocation profile formats and switch everybody to use them.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-03-27 17:09:16 +03:00
Chris Mason
cfed81a04e Btrfs: add the ability to cache a pointer into the eb
This cuts down on the CPU time used by map_private_extent_buffer

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-03-26 17:04:23 -04:00
Chris Mason
727011e07c Btrfs: allow metadata blocks larger than the page size
A few years ago the btrfs code to support blocks lager than
the page size was disabled to fix a few corner cases in the
page cache handling.  This fixes the code to properly support
large metadata blocks again.

Since current kernels will crash early and often with larger
metadata blocks, this adds an incompat bit so that older kernels
can't mount it.

This also does away with different blocksizes for nodes and leaves.
You get a single block size for all tree blocks.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-03-26 16:50:37 -04:00
Josef Bacik
81c9ad237c Btrfs: remove search_start and search_end from find_free_extent and callers
We have been passing nothing but (u64)-1 to find_free_extent for search_end in
all of the callers, so it's completely useless, and we've always been passing 0
in as search_start, so just remove them as function arguments and move
search_start into find_free_extent.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
2012-03-26 14:42:51 -04:00
Jeff Mahoney
49b25e0540 btrfs: enhance transaction abort infrastructure
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
2012-03-22 01:45:40 +01:00
Jeff Mahoney
4da3511342 btrfs: add varargs to btrfs_error
btrfs currently handles most errors with BUG_ON. This patch is a work-in-
 progress but aims to handle most errors other than internal logic
 errors and ENOMEM more gracefully.

 This iteration prevents most crashes but can run into lockups with
 the page lock on occasion when the timing "works out."

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
2012-03-22 01:45:40 +01:00
Jeff Mahoney
2c536799f1 btrfs: btrfs_drop_snapshot should return int
Commit cb1b69f4 (Btrfs: forced readonly when btrfs_drop_snapshot() fails)
made btrfs_drop_snapshot return void because there were no callers checking
the return value. That is the wrong order to handle error propogation since
the caller will have no idea that an error has occured and continue on
as if nothing went wrong.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
2012-03-22 01:45:36 +01:00
Jeff Mahoney
143bede527 btrfs: return void in functions without error conditions
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
2012-03-22 01:45:34 +01:00
Jeff Mahoney
b45a9d8b48 btrfs: btrfs_update_root error push-up
btrfs_update_root BUG's when it can't alloc a path, yet it can recover
from a search error. This patch returns -ENOMEM instead.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
2012-03-22 01:45:33 +01:00
Jeff Mahoney
8c34293001 btrfs: Add btrfs_panic()
As part of the effort to eliminate BUG_ON as an error handling
technique, we need to determine which errors are actual logic errors,
which are on-disk corruption, and which are normal runtime errors
e.g. -ENOMEM.

Annotating these error cases is helpful to understand and report them.

This patch adds a btrfs_panic() routine that will either panic
or BUG depending on the new -ofatal_errors={panic,bug} mount option.
Since there are still so many BUG_ONs, it defaults to BUG for now but I
expect that to change once the error handling effort has made
significant progress.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
2012-03-22 01:45:29 +01:00
Linus Torvalds
855a85f704 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Quoth Chris:
 "This is later than I wanted because I got backed up running through
  btrfs bugs from the Oracle QA teams.  But they are all bug fixes that
  we've queued and tested since rc1.

  Nothing in particular stands out, this just reflects bug fixing and QA
  done in parallel by all the btrfs developers.  The most user visible
  of these is:

    Btrfs: clear the extent uptodate bits during parent transid failures

  Because that helps deal with out of date drives (say an iscsi disk
  that has gone away and come back).  The old code wasn't always
  properly retrying the other mirror for this type of failure."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (24 commits)
  Btrfs: fix compiler warnings on 32 bit systems
  Btrfs: increase the global block reserve estimates
  Btrfs: clear the extent uptodate bits during parent transid failures
  Btrfs: add extra sanity checks on the path names in btrfs_mksubvol
  Btrfs: make sure we update latest_bdev
  Btrfs: improve error handling for btrfs_insert_dir_item callers
  Btrfs: be less strict on finding next node in clear_extent_bit
  Btrfs: fix a bug on overcommit stuff
  Btrfs: kick out redundant stuff in convert_extent_bit
  Btrfs: skip states when they does not contain bits to clear
  Btrfs: check return value of lookup_extent_mapping() correctly
  Btrfs: fix deadlock on page lock when doing auto-defragment
  Btrfs: fix return value check of extent_io_ops
  btrfs: honor umask when creating subvol root
  btrfs: silence warning in raid array setup
  btrfs: fix structs where bitfields and spinlock/atomic share 8B word
  btrfs: delalloc for page dirtied out-of-band in fixup worker
  Btrfs: fix memory leak in load_free_space_cache()
  btrfs: don't check DUP chunks twice
  Btrfs: fix trim 0 bytes after a device delete
  ...
2012-02-24 09:02:53 -08:00
David Sterba
c08782dacd btrfs: fix structs where bitfields and spinlock/atomic share 8B word
On ia64, powerpc64 and sparc64 the bitfield is modified through a RMW cycle and current
gcc rewrites the adjacent 4B word, which in case of a spinlock or atomic has
disaterous effect.

https://lkml.org/lkml/2012/2/1/220

Signed-off-by: David Sterba <dsterba@suse.cz>
2012-02-15 16:40:25 +01:00
Linus Torvalds
d65773b22b Merge branch 'btrfs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
* 'btrfs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  btrfs: take allocation of ->tree_root into open_ctree()
  btrfs: let ->s_fs_info point to fs_info, not root...
  btrfs: consolidate failure exits in btrfs_mount() a bit
  btrfs: make free_fs_info() call ->kill_sb() unconditional
  btrfs: merge free_fs_info() calls on fill_super failures
  btrfs: kill pointless reassignment of ->s_fs_info in btrfs_fill_super()
  btrfs: make open_ctree() return int
  btrfs: sanitizing ->fs_info, part 5
  btrfs: sanitizing ->fs_info, part 4
  btrfs: sanitizing ->fs_info, part 3
  btrfs: sanitizing ->fs_info, part 2
  btrfs: sanitizing ->fs_info, part 1
  btrfs: fix a deadlock in btrfs_scan_one_device()
  btrfs: fix mount/umount race
  btrfs: get ->kill_sb() of its own
  btrfs: preparation to fixing mount/umount race
2012-01-17 15:52:51 -08:00
Chris Mason
c126dea771 Merge branch 'integrity-check-patch-v2' of git://btrfs.giantdisaster.de/git/btrfs into integration
Conflicts:
	fs/btrfs/ctree.h
	fs/btrfs/super.c

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-01-16 15:27:58 -05:00
Chris Mason
9785dbdf26 Merge branch 'for-chris' of git://git.jan-o-sch.net/btrfs-unstable into integration 2012-01-16 15:26:31 -05:00
Ilya Dryomov
a7e99c691a Btrfs: allow for canceling restriper
Implement an ioctl for canceling restriper.  Currently we wait until
relocation of the current block group is finished, in future this can be
done by triggering a commit.  Balance item is deleted and no memory
about the interrupted balance is kept.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-01-16 22:04:49 +02:00
Ilya Dryomov
837d5b6e46 Btrfs: allow for pausing restriper
Implement an ioctl for pausing restriper.  This pauses the relocation,
but balance is still considered to be "in progress": balance item is
not deleted, other volume operations cannot be started, etc.  If paused
in the middle of profile changing operation we will continue making
allocations with the target profile.

Add a hook to close_ctree() to pause restriper and free its data
structures on unmount.  (It's safe to unmount when restriper is in
"paused" state, we will resume with the same parameters on the next
mount)

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-01-16 22:04:49 +02:00
Ilya Dryomov
9555c6c180 Btrfs: add skip_balance mount option
Since restriper kthread starts involuntarily on mount and can suck cpu
and memory bandwidth add a mount option to forcefully skip it.  The
restriper in that case hangs around in paused state and can be resumed
from userspace when it's convenient.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-01-16 22:04:48 +02:00
Ilya Dryomov
0940ebf6b9 Btrfs: save balance parameters to disk
Introduce a new btree objectid for storing balance item.  The reason is
to be able to resume restriper after a crash with the same parameters.
Balance item has a very high objectid and goes into tree of tree roots.

The key for the new item is as follows:

	[ BTRFS_BALANCE_OBJECTID ; BTRFS_BALANCE_ITEM_KEY ; 0 ]

Older kernels simply ignore it so it's safe to mount with an older
kernel and then go back to the newer one.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-01-16 22:04:48 +02:00
Ilya Dryomov
70922617b0 Btrfs: do not reduce profile in do_chunk_alloc()
Every caller of do_chunk_alloc() feeds it the reduced allocation
profile, so stop trying to reduce it one more time.  Instead check the
validity of the passed profile.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-01-16 22:04:48 +02:00
Ilya Dryomov
c9e9f97bdf Btrfs: add basic restriper infrastructure
Add basic restriper infrastructure: extended balancing ioctl and all
related ioctl data structures, add data structure for tracking
restriper's state to fs_info, etc.  The semantics of the old balancing
ioctl are fully preserved.

Explicitly disallow any volume operations when balance is in progress.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-01-16 22:04:47 +02:00
Ilya Dryomov
a46d11a8b0 Btrfs: add BTRFS_AVAIL_ALLOC_BIT_SINGLE bit
Right now on-disk BTRFS_BLOCK_GROUP_* profile bits are used for
avail_{data,metadata,system}_alloc_bits fields, which gather info about
available allocation profiles in the FS.  When chunk is created or read
from disk, its profile is OR'ed with the corresponding avail_alloc_bits
field.  Since SINGLE is denoted by 0 in the on-disk format, currently
there is no way to tell when such chunks become avaialble.  Restriper
needs that information, so add a separate bit for SINGLE profile.

This bit is going to be in-memory only, it should never be written out
to disk, so it's not a disk format change.  However to avoid remappings
in future, reserve corresponding on-disk bit.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-01-16 22:04:47 +02:00
Ilya Dryomov
52ba692972 Btrfs: introduce masks for chunk type and profile
Chunk's type and profile are encoded in u64 flags field.  Introduce
masks to easily access them.  Also fix the type of BTRFS_BLOCK_GROUP_*
constants, it should be ULL.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-01-16 22:04:47 +02:00
Ilya Dryomov
6fef8df1dc Btrfs: get rid of *_alloc_profile fields
{data,metadata,system}_alloc_profile fields have been unused for a long
time now.  Get rid of them.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2012-01-16 22:04:47 +02:00
Al Viro
815745cf3e btrfs: let ->s_fs_info point to fs_info, not root...
the latter can be obtained from the former (by looking as ->tree_root)
just as cheaply as we currently are doing the other way round.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-08 19:35:37 -05:00
Arne Jansen
66d7e7f09f Btrfs: mark delayed refs as for cow
Add a for_cow parameter to add_delayed_*_ref and pass the appropriate value
from every call site. The for_cow parameter will later on be used to
determine if a ref will change anything with respect to qgroups.

Delayed refs coming from relocation are always counted as for_cow, as they
don't change subvol quota.

Also pass in the fs_info for later use.

btrfs_find_all_roots() will use this as an optimization, as changes that are
for_cow will not change anything with respect to which root points to a
certain leaf. Thus, we don't need to add the current sequence number to
those delayed refs.

Signed-off-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2011-12-22 16:22:27 +01:00
Jan Schmidt
c7d22a3c3c Btrfs: added helper btrfs_next_item()
btrfs_next_item() makes the btrfs path point to the next item, crossing leaf
boundaries if needed.

Signed-off-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2011-12-22 16:22:26 +01:00
Stefan Behrens
21adbd5cbb Btrfs: integrate integrity check module into btrfs
This is the last part of the patch series. It modifies the btrfs
code to use the integrity check module if configured to do so
with the define BTRFS_FS_CHECK_INTEGRITY. If this define is not set,
the only effective change is that code is added that handles the
mount option to activate the integrity check. If the mount option is
set and the define BTRFS_FS_CHECK_INTEGRITY is not set, that code
complains in the log and the mount fails with EINVAL.

Add the mount option to activate the usage of the integrity check
code.
Add invocation of btrfs integrity check code init and cleanup
function on mount and umount, respectively.
Add hook to call btrfs integrity check code version of
submit_bh/submit_bio.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
2011-12-21 19:14:17 +01:00
Josef Bacik
22c44fe65a Btrfs: deal with enospc from dirtying inodes properly
Now that we're properly keeping track of delayed inode space we've been getting
a lot of warnings out of btrfs_dirty_inode() when running xfstest 83.  This is
because a bunch of people call mark_inode_dirty, which is void so we can't
return ENOSPC.  This needs to be fixed in a few areas

1) file_update_time - this updates the mtime and such when writing to a file,
which will call mark_inode_dirty.  So copy file_update_time into btrfs so we can
call btrfs_dirty_inode directly and return an error if we get one appropriately.

2) fix symlinks to use btrfs_setattr for ->setattr.  For some reason we weren't
setting ->setattr for symlinks, even though we should have been.  This catches
one of the cases where we were getting errors in mark_inode_dirty.

3) Fix btrfs_setattr and btrfs_setsize to call btrfs_dirty_inode directly
instead of mark_inode_dirty.  This lets us return errors properly for truncate
and chown/anything related to setattr.

4) Add a new btrfs_fs_dirty_inode which will just call btrfs_dirty_inode and
print an error if we have one.  The only remaining user we can't control for
this is touch_atime(), but we don't really want to keep people from walking
down the tree if we don't have space to save the atime update, so just complain
but don't worry about it.

With this patch xfstests 83 complains a handful of times instead of hundreds of
times.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
2011-12-15 11:04:21 -05:00
Miao Xie
aa38a711a8 Btrfs: fix deadlock on metadata reservation when evicting a inode
When I ran the xfstests, I found the test tasks was blocked on meta-data
reservation.

By debugging, I found the reason of this bug:
   start transaction
        |
	v
   reserve meta-data space
	|
	v
   flush delay allocation -> iput inode -> evict inode
	^					|
	|					v
   wait for delay allocation flush <- reserve meta-data space

And besides that, the flush on evicting inode will block the thread, which
is reclaiming the memory, and make oom happen easily.

Fix this bug by skipping the flush step when evicting inode.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
2011-11-30 18:46:03 +01:00
Josef Bacik
291c7d2f57 Btrfs: wait on caching if we're loading the free space cache
We've been hitting panics when running xfstest 13 in a loop for long periods of
time.  And actually this problem has always existed so we've been hitting these
things randomly for a while.  Basically what happens is we get a thread coming
into the allocator and reading the space cache off of disk and adding the
entries to the free space cache as we go.  Then we get another thread that comes
in and tries to allocate from that block group.  Since block_group->cached !=
BTRFS_CACHE_NO it goes ahead and tries to do the allocation.  We do this because
if we're doing the old slow way of caching we don't want to hold people up and
wait for everything to finish.  The problem with this is we could end up
discarding the space cache at some arbitrary point in the future, which means we
could very well end up allocating space that is either bad, or when the real
caching happens it could end up thinking the space isn't in use when it really
is and cause all sorts of other problems.

The solution is to add a new flag to indicate we are loading the free space
cache from disk, and always try to cache the block group if cache->cached !=
BTRFS_CACHE_FINISHED.  That way if we are loading the space cache anybody else
who tries to allocate from the block group will have to wait until it's finished
to make sure it completes successfully.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
2011-11-20 07:42:16 -05:00
Liu Bo
f1ebcc74d5 Btrfs: fix tree corruption after multi-thread snapshots and inode_cache flush
The btrfs snapshotting code requires that once a root has been
snapshotted, we don't change it during a commit.

But there are two cases to lead to tree corruptions:

1) multi-thread snapshots can commit serveral snapshots in a transaction,
   and this may change the src root when processing the following pending
   snapshots, which lead to the former snapshots corruptions;

2) the free inode cache was changing the roots when it root the cache,
   which lead to corruptions.

This fixes things by making sure we force COW the block after we create a
snapshot during commiting a transaction, then any changes to the roots
will result in COW, and we get all the fs roots and snapshot roots to be
consistent.

Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-11-15 09:53:28 -05:00
Chris Mason
531f4b1ae5 Merge branch 'for-chris' of git://github.com/sensille/linux into integration
Conflicts:
	fs/btrfs/ctree.h

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-11-06 03:05:08 -05:00
Josef Bacik
c06a0e120a Btrfs: fix delayed insertion reservation
We all keep getting those stupid warnings from use_block_rsv when running
stress.sh, and it's because the delayed insertion stuff is being stupid.  It's
not the delayed insertion stuffs fault, it's all just stupid.  When marking an
inode dirty for oh say updating the time on it, we just do a
btrfs_join_transaction, which doesn't reserve any space.  This is stupid because
we're going to have to have space reserve to make this change, but we do it
because it's fast because chances are we're going to call it over and over again
and it doesn't matter.  Well thanks to the delayed insertion stuff this is
mostly the case, so we do actually need to make this reservation.  So if
trans->bytes_reserved is 0 then try to do a normal reservation.  If not return
ENOSPC which will make the btrfs_dirty_inode start a proper transaction which
will let it do the whole ENOSPC dance and reserve enough space for the delayed
insertion to steal the reservation from the transaction.

The other stupid thing we do is not reserve space for the inode when writing to
the thing.  Usually this is ok since we have to update the time so we'd have
already done all this work before we get to the endio stuff, so it doesn't
matter.  But this is stupid because we could write the data after the
transaction commits where we changed the mtime of the inode so we have to cow
all the way down to the inode anyway.  This used to be masked by the delalloc
reservation stuff, but because we delay the update it doesn't get masked in this
case.  So again the delayed insertion stuff bites us in the ass.  So if our
trans->block_rsv is delalloc, just steal the reservation from the delalloc
reserve.  Hopefully this won't bite us in the ass, but I've said that before.

With this patch stress.sh no longer spits out those stupid warnings (famous last
words).  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-11-06 03:04:20 -05:00
Josef Bacik
6d668dda0c Btrfs: make a delayed_block_rsv for the delayed item insertion
I've been hitting warnings in use_block_rsv when running the delayed insertion
stuff.  It's because we will readjust global block rsv based on what is in use,
which means we could end up discarding reservations that are for the delayed
insertion stuff.  So instead create a seperate block rsv for the delayed
insertion stuff.  This will also make it easier to debug problems with the
delayed insertion reservations since we will know that only the delayed
insertion code touches this block_rsv.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-11-06 03:04:18 -05:00
Chris Mason
af31f5e5b8 Btrfs: add a log of past tree roots
This takes some of the free space in the btrfs super block
to record information about most of the roots in the last four
commits.

It also adds a -o recovery to use the root history log when
we're not able to read the tree of tree roots, the extent
tree root, the device tree root or the csum root.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-11-06 03:04:15 -05:00
David Sterba
6c41761fc6 btrfs: separate superblock items out of fs_info
fs_info has now ~9kb, more than fits into one page. This will cause
mount failure when memory is too fragmented. Top space consumers are
super block structures super_copy and super_for_commit, ~2.8kb each.
Allocate them dynamically. fs_info will be ~3.5kb. (measured on x86_64)

Add a wrapper for freeing fs_info and all of it's dynamically allocated
members.

Signed-off-by: David Sterba <dsterba@suse.cz>
2011-11-06 03:04:01 -05:00
Chris Mason
e688b7252f Btrfs: fix extent pinning bugs in the tree log
The tree log had two important bugs that could cause corruptions after a
crash.  Sometimes we were allowing tree log blocks to be reused after
the tree log was committed but before the transaction commit was done.

This allowed a future metadata write to overwrite the tree log data.  It
is fixed by adding a new variant of freeing reserved extents that always
pins them.  Credit goes to Stefan Behrens and Arne Jansen for many many
hours spent tracking this bug down.

During tree log replay, we do a pass through the tree log and pin all
the extents we find.  This makes sure the replay code won't go in and
use any of those blocks for new allocations during replay.  The problem
is the free space cache isn't honoring these pinned extents.  So the
allocator can end up handing them out, leading to all kinds of problems
during replay.

The fix here is to force any free space cache to load while we pin the
extents, and then to make sure we remove the pinned extents from the
free space rbtree.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
Reported-by: Stefan Behrens <sbehrens@giantdisaster.de>
2011-11-06 03:03:48 -05:00
Josef Bacik
36ba022ac0 Btrfs: seperate out btrfs_block_rsv_check out into 2 different functions
Currently btrfs_block_rsv_check does 2 things, it will either refill a block
reserve like in the truncate or refill case, or it will check to see if there is
enough space in the global reserve and possibly refill it.  However because of
overcommit we could be well overcommitting ourselves just to try and refill the
global reserve, when really we should just be committing the transaction.  So
breack this out into btrfs_block_rsv_refill and btrfs_block_rsv_check.  Refill
will try to reserve more metadata if it can and btrfs_block_rsv_check will not,
it will only tell you if the factor of the total space is still reserved.
Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
2011-10-19 15:12:59 -04:00
Josef Bacik
5b0e95bf60 Btrfs: inline checksums into the disk free space cache
Yeah yeah I know this is how we used to do it and then I changed it, but damnit
I'm changing it back.  The fact is that writing out checksums will modify
metadata, which could cause us to dirty a block group we've already written out,
so we have to truncate it and all of it's checksums and re-write it which will
write new checksums which could dirty a blockg roup that has already been
written and you see where I'm going with this?  This can cause unmount or really
anything that depends on a transaction to commit to take it's sweet damned time
to happen.  So go back to the way it was, only this time we're specifically
setting NODATACOW because we can't go through the COW pathway anyway and we're
doing our own built-in cow'ing by truncating the free space cache.  The other
new thing is once we truncate the old cache and preallocate the new space, we
don't need to do that song and dance at all for the rest of the transaction, we
can just overwrite the existing space with the new cache if the block group
changes for whatever reason, and the NODATACOW will let us do this fine.  So
keep track of which transaction we last cleared our cache in and if we cleared
it in this transaction just say we're all setup and carry on.  This survives
xfstests and stress.sh.

The inode cache will continue to use the normal csum infrastructure since it
only gets written once and there will be no more modifications to the fs tree in
a transaction commit.

Signed-off-by: Josef Bacik <josef@redhat.com>
2011-10-19 15:12:54 -04:00
Josef Bacik
2bf64758fd Btrfs: allow us to overcommit our enospc reservations
One of the things that kills us is the fact that our ENOSPC reservations are
horribly over the top in most normal cases.  There isn't too much that can be
done about this because when we are completely full we really need them to work
like this so we don't under reserve.  However if there is plenty of unallocated
chunks on the disk we can use that to gauge how much we can overcommit.  So this
patch adds chunk free space accounting so we always know how much unallocated
space we have.  Then if we fail to make a reservation within our allocated
space, check to see if we can overcommit.  In the normal flushing case (like
with delalloc metadata reservations) we'll take the free space and divide it by
2 if our metadata profile is setup for DUP or any of those, and then divide it
by 8 to make sure we don't overcommit too much.  Then if we're in a non-flushing
case (we really need this reservation now!) we only limit ourselves to half of
the free space.  This makes this fio test

[torrent]
filename=torrent-test
rw=randwrite
size=4g
ioengine=sync
directory=/mnt/btrfs-test

go from taking around 45 minutes to 10 seconds on my freshly formatted 3 TiB
file system.  This doesn't seem to break my other enospc tests, but could really
use some more testing as this is a super scary change.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
2011-10-19 15:12:50 -04:00
Josef Bacik
3b16a4e3c3 Btrfs: use the inode's mapping mask for allocating pages
Johannes pointed out we were allocating only kernel pages for doing writes,
which is kind of a big deal if you are on 32bit and have more than a gig of ram.
So fix our allocations to use the mapping's gfp but still clear __GFP_FS so we
don't re-enter.  Thanks,

Reported-by: Johannes Weiner <jweiner@redhat.com>
Signed-off-by: Josef Bacik <josef@redhat.com>
2011-10-19 15:12:45 -04:00
Josef Bacik
4a92b1b8d2 Btrfs: stop passing a trans handle all around the reservation code
The only thing that we need to have a trans handle for is in
reserve_metadata_bytes and thats to know how much flushing we can do.  So
instead of passing it around, just check current->journal_info for a
trans_handle so we know if we can commit a transaction to try and free up space
or not.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
2011-10-19 15:12:44 -04:00
Josef Bacik
482e6dc526 Btrfs: allow callers to specify if flushing can occur for btrfs_block_rsv_check
If you run xfstest 224 it you will get lots of messages about not being able to
delete inodes and that they will be cleaned up next mount.  This is because
btrfs_block_rsv_check was not calling reserve_metadata_bytes with the ability to
flush, so if there was not enough space, it simply failed.  But in truncate and
evict case we could easily flush space to try and get enough space to do our
work, so make btrfs_block_rsv_check take a flush argument to pass down to
reserve_metadata_bytes.  Now xfstests 224 runs fine without all those
complaints.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
2011-10-19 15:12:38 -04:00
Josef Bacik
07127184ef Btrfs: reduce the amount of space needed for truncates
With btrfs_truncate_inode_items we always return if we have to go to another
leaf, which makes us do our reservation again.  This means we will only ever
modify one leaf at a time, so we only need 1 items worth of slack space.  Also,
since we are deleting we will not be creating nodes as we go down, if anything
we'll be free'ing them as we merge them together, so make a different
calculation for truncate which will only have the worst case useage of COW'ing
the entire path down to the leaf.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
2011-10-19 15:12:37 -04:00
Josef Bacik
5e962c7850 Btrfs: kill btrfs_truncate_reserve_metadata
Since we've optimized the truncate path, we no longer require this function.

Signed-off-by: Josef Bacik <josef@redhat.com>
2011-10-19 15:12:36 -04:00
Josef Bacik
dabdb6408c Btrfs: kill unused parts of block_rsv
The priority and refill_used flags are not used anymore, and neither is the
usage counter, so just remove them from btrfs_block_rsv.

Signed-off-by: Josef Bacik <josef@redhat.com>
2011-10-19 15:12:34 -04:00
Josef Bacik
37be25bcb6 Btrfs: kill the durable block rsv stuff
This is confusing code and isn't used by anything anymore, so delete it.

Signed-off-by: Josef Bacik <josef@redhat.com>
2011-10-19 15:12:32 -04:00
Josef Bacik
dba68306f3 Btrfs: kill the orphan space calculation for snapshots
This patch kills off the calculation for the amount of space needed for the
orphan operations during a snapshot.  The thing is we only do snapshots on
commit, so any space that is in the block_rsv->freed[] isn't going to be in the
new snapshot anyway, so there isn't any reason to require that space to be
reserved for the snapshot to occur.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
2011-10-19 15:12:32 -04:00
Josef Bacik
fb25e9141a Btrfs: use bytes_may_use for all ENOSPC reservations
We have been using bytes_reserved for metadata reservations, which is wrong
since we use that to keep track of outstanding reservations from the allocator.
This resulted in us doing a lot of silly things to make sure we don't allocate a
bunch of metadata chunks since we never had a real view of how much space was
actually in use by metadata.

This passes Arne's enospc test and xfstests as well as my own enospc tests.
Hopefully this will get us moving in the right direction.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
2011-10-19 15:12:30 -04:00
Arne Jansen
7414a03fbf btrfs: initial readahead code and prototypes
This is the implementation for the generic read ahead framework.

To trigger a readahead, btrfs_reada_add must be called. It will start
a read ahead for the given range [start, end) on tree root. The returned
handle can either be used to wait on the readahead to finish
(btrfs_reada_wait), or to send it to the background (btrfs_reada_detach).

The read ahead works as follows:
On btrfs_reada_add, the root of the tree is inserted into a radix_tree.
reada_start_machine will then search for extents to prefetch and trigger
some reads. When a read finishes for a node, all contained node/leaf
pointers that lie in the given range will also be enqueued. The reads will
be triggered in sequential order, thus giving a big win over a naive
enumeration. It will also make use of multi-device layouts. Each disk
will have its on read pointer and all disks will by utilized in parallel.
Also will no two disks read both sides of a mirror simultaneously, as this
would waste seeking capacity. Instead both disks will read different parts
of the filesystem.
Any number of readaheads can be started in parallel. The read order will be
determined globally, i.e. 2 parallel readaheads will normally finish faster
than the 2 started one after another.

Changes v2:
 - protect root->node by transaction instead of node_lock
 - fix missed branches:
    The readahead had a too simple check to determine if a branch from
    a node should be checked or not. It now also records the upper bound
    of each node to see if the requested RA range lies within.
 - use KERN_CONT to debug output, to avoid line breaks
 - defer reada_start_machine to worker to avoid deadlock

Changes v3:
 - protect root->node by rcu

Changes v5:
 - changed EIO-semantics of reada_tree_block_flagged
 - remove spin_lock from reada_control and make elems an atomic_t
 - remove unused read_total from reada_control
 - kill reada_key_cmp, use btrfs_comp_cpu_keys instead
 - use kref-style release functions where possible
 - return struct reada_control * instead of void * from btrfs_reada_add

Signed-off-by: Arne Jansen <sensille@gmx.net>
2011-10-02 08:48:44 +02:00
Arne Jansen
90519d66ab btrfs: state information for readahead
Add state information for readahead to btrfs_fs_info and btrfs_device

Changes v2:
 - don't wait in radix_trees
 - add own set of workers for readahead

Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Arne Jansen <sensille@gmx.net>
2011-10-02 08:48:30 +02:00
Chris Mason
81d86e1b70 Merge branch 'btrfs-3.0' into for-linus 2011-08-18 10:38:03 -04:00
Li Zefan
c97c2916e2 Btrfs: use plain page_address() in header fields setget functions
We've stopped using highmem for extent buffers.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-08-16 21:09:15 -04:00
Tsutomu Itoh
cb1b69f450 Btrfs: forced readonly when btrfs_drop_snapshot() fails
The filesystem turns readonly instead of returning the error to the
caller when detected error in btrfs_drop_snapshot().
and, because the caller doesn't check the error, the function type is
changed to 'void'.

Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-08-16 21:09:15 -04:00
Linus Torvalds
ed8f37370d Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: (31 commits)
  Btrfs: don't call writepages from within write_full_page
  Btrfs: Remove unused variable 'last_index' in file.c
  Btrfs: clean up for find_first_extent_bit()
  Btrfs: clean up for wait_extent_bit()
  Btrfs: clean up for insert_state()
  Btrfs: remove unused members from struct extent_state
  Btrfs: clean up code for merging extent maps
  Btrfs: clean up code for extent_map lookup
  Btrfs: clean up search_extent_mapping()
  Btrfs: remove redundant code for dir item lookup
  Btrfs: make acl functions really no-op if acl is not enabled
  Btrfs: remove remaining ref-cache code
  Btrfs: remove a BUG_ON() in btrfs_commit_transaction()
  Btrfs: use wait_event()
  Btrfs: check the nodatasum flag when writing compressed files
  Btrfs: copy string correctly in INO_LOOKUP ioctl
  Btrfs: don't print the leaf if we had an error
  btrfs: make btrfs_set_root_node void
  Btrfs: fix oops while writing data to SSD partitions
  Btrfs: Protect the readonly flag of block group
  ...

Fix up trivial conflicts (due to acl and writeback cleanups) in
 - fs/btrfs/acl.c
 - fs/btrfs/ctree.h
 - fs/btrfs/extent_io.c
2011-08-02 21:14:05 -10:00
Li Zefan
9b89d95a14 Btrfs: make acl functions really no-op if acl is not enabled
So there's no overhead for something we don't use.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-08-01 14:30:48 -04:00
Mark Fasheh
bf5f32ecb6 btrfs: make btrfs_set_root_node void
This is fairly trivial - btrfs_set_root_node() - always returns zero so we
can just make it void.  All callers ignore the return code now anyway.  I
also made sure to check that none of the functions that
btrfs_set_root_node() calls returns an error that we might have needed to
catch and pass back.

Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-08-01 14:30:44 -04:00
Li Zefan
b6973aa622 Btrfs: fix readahead in file defrag
We passed the wrong value to btrfs_force_ra(). Fix this by changing
the argument of btrfs_force_ra() from last_index to nr_page.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-08-01 14:30:42 -04:00
Linus Torvalds
22712200e1 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
  Btrfs: make sure reserve_metadata_bytes doesn't leak out strange errors
  Btrfs: use the commit_root for reading free_space_inode crcs
  Btrfs: reduce extent_state lock contention for metadata
  Btrfs: remove lockdep magic from btrfs_next_leaf
  Btrfs: make a lockdep class for each root
  Btrfs: switch the btrfs tree locks to reader/writer
  Btrfs: fix deadlock when throttling transactions
  Btrfs: stop using highmem for extent_buffers
  Btrfs: fix BUG_ON() caused by ENOSPC when relocating space
  Btrfs: tag pages for writeback in sync
  Btrfs: fix enospc problems with delalloc
  Btrfs: don't flush delalloc arbitrarily
  Btrfs: use find_or_create_page instead of grab_cache_page
  Btrfs: use a worker thread to do caching
  Btrfs: fix how we merge extent states and deal with cached states
  Btrfs: use the normal checksumming infrastructure for free space cache
  Btrfs: serialize flushers in reserve_metadata_bytes
  Btrfs: do transaction space reservation before joining the transaction
  Btrfs: try to only do one btrfs_search_slot in do_setxattr
2011-07-27 16:43:52 -07:00
Chris Mason
ff95acb673 Merge branch 'integration' into for-linus 2011-07-27 16:18:13 -04:00
Chris Mason
bd681513fa Btrfs: switch the btrfs tree locks to reader/writer
The btrfs metadata btree is the source of significant
lock contention, especially in the root node.   This
commit changes our locking to use a reader/writer
lock.

The lock is built on top of rw spinlocks, and it
extends the lock tracking to remember if we have a
read lock or a write lock when we go to blocking.  Atomics
count the number of blocking readers or writers at any
given time.

It removes all of the adaptive spinning from the old code
and uses only the spinning/blocking hints inside of btrfs
to decide when it should continue spinning.

In read heavy workloads this is dramatically faster.  In write
heavy workloads we're still faster because of less contention
on the root node lock.

We suffer slightly in dbench because we schedule more often
during write locks, but all other benchmarks so far are improved.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-07-27 12:46:46 -04:00
Josef Bacik
9e0baf60de Btrfs: fix enospc problems with delalloc
So I had this brilliant idea to use atomic counters for outstanding and reserved
extents, but this turned out to be a bad idea.  Consider this where we have 1
outstanding extent and 1 reserved extent

Reserver				Releaser
					atomic_dec(outstanding) now 0
atomic_read(outstanding)+1 get 1
atomic_read(reserved) get 1
don't actually reserve anything because
they are the same
					atomic_cmpxchg(reserved, 1, 0)
atomic_inc(outstanding)
atomic_add(0, reserved)
					free reserved space for 1 extent

Then the reserver now has no actual space reserved for it, and when it goes to
finish the ordered IO it won't have enough space to do it's allocation and you
get those lovely warnings.

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-07-27 12:46:44 -04:00
Josef Bacik
bab39bf998 Btrfs: use a worker thread to do caching
A user reported a deadlock when copying a bunch of files.  This is because they
were low on memory and kthreadd got hung up trying to migrate pages for an
allocation when starting the caching kthread.  The page was locked by the person
starting the caching kthread.  To fix this we just need to use the async thread
stuff so that the threads are already created and we don't have to worry about
deadlocks.  Thanks,

Reported-by: Roman Mamedov <rm@romanrm.ru>
Signed-off-by: Josef Bacik <josef@redhat.com>
2011-07-27 12:46:25 -04:00
Christoph Hellwig
4e34e719e4 fs: take the ACL checks to common code
Replace the ->check_acl method with a ->get_acl method that simply reads an
ACL from disk after having a cache miss.  This means we can replace the ACL
checking boilerplate code with a single implementation in namei.c.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-25 14:30:23 -04:00
Josef Bacik
02c24a8218 fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers
Btrfs needs to be able to control how filemap_write_and_wait_range() is called
in fsync to make it less of a painful operation, so push down taking i_mutex and
the calling of filemap_write_and_wait() down into the ->fsync() handlers.  Some
file systems can drop taking the i_mutex altogether it seems, like ext3 and
ocfs2.  For correctness sake I just pushed everything down in all cases to make
sure that we keep the current behavior the same for everybody, and then each
individual fs maintainer can make up their mind about what to do from there.
Thanks,

Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 20:47:59 -04:00
Josef Bacik
b26751575a Btrfs: implement our own ->llseek
In order to handle SEEK_HOLE/SEEK_DATA we need to implement our own llseek.
Basically for the normal SEEK_*'s we will just defer to the generic helper, and
for SEEK_HOLE/SEEK_DATA we will use our fiemap helper to figure out the nearest
hole or data.  Currently this helper doesn't check for delalloc bytes for
prealloc space, so for now treat prealloc as data until that is fixed.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 20:47:56 -04:00
Al Viro
0ee5dc676a btrfs: kill magical embedded struct superblock
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 01:44:20 -04:00
Al Viro
7e40145eb1 ->permission() sanitizing: don't pass flags to ->check_acl()
not used in the instances anymore.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 01:43:21 -04:00
Josef Bacik
fdb5effd5c Btrfs: serialize flushers in reserve_metadata_bytes
We keep having problems with early enospc, and that's because our method of
making space is inherently racy.  The problem is we can have one guy trying to
make space for himself, and in the meantime people come in and steal his
reservation.  In order to stop this we make a waitqueue and put anybody who
comes into reserve_metadata_bytes on that waitqueue if somebody is trying to
make more space.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
2011-07-11 09:58:48 -04:00