Commit graph

189 commits

Author SHA1 Message Date
Qu Wenruo 442244c963 btrfs: qgroup: Switch self test to extent-oriented qgroup mechanism.
Since the self test transaction don't have delayed_ref_roots, so use
find_all_roots() and export btrfs_qgroup_account_extent() to simulate it

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:26:05 -07:00
Qu Wenruo 9d220c95f5 btrfs: qgroup: Switch rescan to new mechanism.
Switch rescan to use the new new extent oriented mechanism.

As rescan is also based on extent, new mechanism is just a perfect match
for rescan.

With re-designed internal functions, rescan is quite easy, just call
btrfs_find_all_roots() and then btrfs_qgroup_account_one_extent().

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:25:54 -07:00
Qu Wenruo 550d7a2ed5 btrfs: qgroup: Add new qgroup calculation function
btrfs_qgroup_account_extents().

The new btrfs_qgroup_account_extents() function should be called in
btrfs_commit_transaction() and it will update all the qgroup according
to delayed_ref_root->dirty_extent_root.

The new function can handle both normal operation during
commit_transaction() or in rescan in a unified method with clearer
logic.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:25:49 -07:00
Qu Wenruo 3b7d00f99c btrfs: qgroup: Add new function to record old_roots.
Add function btrfs_qgroup_prepare_account_extents() to get old_roots
which are needed for qgroup.

We do it in commit_transaction() and before switch_roots(), and only
search commit_root, so it gives a quite accurate view for previous
transaction.

With old_roots from previous transaction, we can use it to do accurate
account with current transaction.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:25:39 -07:00
Qu Wenruo 3368d001ba btrfs: qgroup: Record possible quota-related extent for qgroup.
Add hook in add_delayed_ref_head() to record quota-related extent record
into delayed_ref_root->dirty_extent_record rb-tree for later qgroup
accounting.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:25:32 -07:00
Qu Wenruo 823ae5b8e3 btrfs: qgroup: Add function qgroup_update_counters().
Add function qgroup_update_counters(), which will update related
qgroups' rfer/excl according to old/new_roots.

This is one of the two core functions for the new qgroup implement.

This is based on btrfs_adjust_coutners() but with clearer logic and
comment.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:25:28 -07:00
Qu Wenruo d810ef2be5 btrfs: qgroup: Add function qgroup_update_refcnt().
This function is used to update refcnt for qgroups.
And is one of the two core functions used in the new qgroup implement.

This is based on the old update_old/new_refcnt, but provides a unified
logic and behavior.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:25:24 -07:00
Qu Wenruo 9c542136fd btrfs: qgroup: Cleanup open-coded old/new_refcnt update and read.
Use inline functions to do such things, to improve readability.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Acked-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:25:13 -07:00
Christian Engelmayer ab3680dd18 btrfs: qgroup: Fix possible leak in btrfs_add_qgroup_relation()
Commit 9c8b35b1ba ("btrfs: quota: Automatically update related qgroups or
mark INCONSISTENT flags when assigning/deleting a qgroup relations.")
introduced the allocation of a temporary ulist in function
btrfs_add_qgroup_relation() and added the corresponding cleanup to the out
path. However, the allocation was introduced before the src/dst level check
that directly returns. Fix the possible leakage of the ulist by moving the
allocation after the input validation. Detected by Coverity CID 1295988.

Signed-off-by: Christian Engelmayer <cengelma@gmx.at>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-02 19:34:35 -07:00
Qu Wenruo 9c8b35b1ba btrfs: quota: Automatically update related qgroups or mark INCONSISTENT flags when assigning/deleting a qgroup relations.
Operation like qgroups assigning/deleting qgroup relations will mostly
cause qgroup data inconsistent, since it needs to do the full rescan to
determine whether shared extents are exclusive or still shared in
parent qgroups.

But there are some exceptions, like qgroup with only exclusive extents
(qgroup->excl == qgroup->rfer), in that case, we only needs to
modify all its parents' excl and rfer.

So this patch adds a quick path for such qgroup in qgroup
assign/remove routine, and if quick path failed, the qgroup status will
be marked INCONSISTENT, and return 1 to info user-land.

BTW since the quick path is much the same of qgroup_excl_accounting(),
so move the core of it to __qgroup_excl_accounting() and reuse it.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:52:59 -07:00
Dongsheng Yang 8ea0ec9e01 btrfs: qgroup: clear STATUS_FLAG_ON in disabling quota.
we forgot to clear STATUS_FLAG_ON in quota_disable(), it
will cause a problem shown as below:

	# mount /dev/sdc /mnt
	# btrfs quota enable /mnt
	# btrfs quota disable /mnt
	# btrfs quota rescan /mnt
	quota rescan started <--- expecting it fail here.
	# echo $?
	0

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:52:58 -07:00
Qu Wenruo 53b7cde9d5 btrfs: Update btrfs qgroup status item when rescan is done.
Update qgroup status when rescan is done.

Before this patch, status item is not updated on rescan finish, which
causing the RESCAN and INCONSISTENT flags never cleared.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:52:57 -07:00
Qu Wenruo 3393168d22 btrfs: qgroup: Fix dead judgement on qgroup_rescan_leaf() return value.
Old qgroup_rescan_leaf() comment indicates ret == 2 as complete and
cleared INCONSISTENT flag.

This is not true since it will never return 2, and inside it no codes
will clear INCONSISTENT flag.
The flag clearance is done in btrfs_qgroup_rescan_work().
This caused the bug that INCONSISTENT flag is never cleared.

So change the comment and fix the dead judgment.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:52:55 -07:00
Qu Wenruo 8465ecec96 btrfs: Check qgroup level in kernel qgroup assign.
Although we have qgroup level check in btrfs-progs, it's not enough
since other programe may still call ioctl directly not using
btrfs-progs. For example, systemd.

But it's btrfs-progs to be blame since we don't provide a
full-function(like subvolume create things) btrfs library with enough
check, and only rely on kernel ioctl.

So Add level checks in kernel too.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:52:53 -07:00
Dongsheng Yang f5a6b1c53b btrfs: qgroup: allow to remove qgroup which has parent but no child.
When a qgroup has parents but no child, it should be removable in
Theory I think. But currently, we can not remove it when it has
either parent or child.

Example:
	# btrfs quota enable /mnt
	# btrfs qgroup create 1/0 /mnt
	# btrfs qgroup create 2/0 /mnt
	# btrfs qgroup assign 1/0 2/0 /mnt
	# btrfs qgroup show -pcre /mnt
qgroupid rfer  excl  max_rfer max_excl parent  child
-------- ----  ----  -------- -------- ------  -----
0/5      16384 16384 0        0        ---     ---
1/0      0     0     0        0        2/0     ---
2/0      0     0     0        0        ---     1/0

At this time, there is no subvol or qgroup depending on it.
Just a qgroup 2/0 is its parent, but 2/0 can work well without
1/0. So I think 1/0 should be removalbe. But:
	# btrfs qgroup destroy 1/0 /mnt
ERROR: unable to destroy quota group: Device or resource busy

This patch remove the check of qgroup->parent in removing it,
then we can remove a qgroup when it has a parent.

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:52:52 -07:00
Dongsheng Yang 09870d2772 btrfs: qgroup: return EINVAL if level of parent is not higher than child's.
When we create a subvol inheriting a qgroup, we need to check the level
of them. Otherwise, there is a chance a qgroup can inherit another qgroup
at the same level.

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:52:51 -07:00
Dongsheng Yang e2d1f92399 btrfs: qgroup: do a reservation in a higher level.
There are two problems in qgroup:

a). The PAGE_CACHE is 4K, even when we are writing a data of 1K,
qgroup will reserve a 4K size. It will cause the last 3K in a qgroup
is not available to user.

b). When user is writing a inline data, qgroup will not reserve it,
it means this is a window we can exceed the limit of a qgroup.

The main idea of this patch is reserving the data size of write_bytes
rather than the reserve_bytes. It means qgroup will not care about
the data size btrfs will reserve for user, but only care about the
data size user is going to write. Then reserve it when user want to
write and release it in transaction committed.

In this way, qgroup can be released from the complex procedure in
btrfs and only do the reserve when user want to write and account
when the data is written in commit_transaction().

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:52:50 -07:00
Dongsheng Yang 31193213f1 Btrfs: qgroup: Introduce a may_use to account space_info->bytes_may_use.
Currently, for pre_alloc or delay_alloc, the bytes will be accounted
in space_info by the three guys.
space_info->bytes_may_use --- space_info->reserved --- space_info->used.
But on the other hand, in qgroup, there are only two counters to account the
bytes, qgroup->reserved and qgroup->excl. And qg->reserved accounts
bytes in space_info->bytes_may_use and qg->excl accounts bytes in
space_info->used. So the bytes in space_info->reserved is not accounted
in qgroup. If so, there is a window we can exceed the quota limit when
bytes is in space_info->reserved.

Example:
	# btrfs quota enable /mnt
	# btrfs qgroup limit -e 10M /mnt
	# for((i=0;i<20;i++));do fallocate -l 1M /mnt/data$i; done
	# sync
	# btrfs qgroup show -pcre /mnt
qgroupid rfer     excl     max_rfer max_excl parent  child
-------- ----     ----     -------- -------- ------  -----
0/5      20987904 20987904 0        10485760 ---     ---

qg->excl is 20987904 larger than max_excl 10485760.

This patch introduce a new counter named may_use to qgroup, then
there are three counters in qgroup to account bytes in space_info
as below.
space_info->bytes_may_use --- space_info->reserved --- space_info->used.
qgroup->may_use           --- qgroup->reserved     --- qgroup->excl

With this patch applied:
	# btrfs quota enable /mnt
	# btrfs qgroup limit -e 10M /mnt
	# for((i=0;i<20;i++));do fallocate -l 1M /mnt/data$i; done
fallocate: /mnt/data9: fallocate failed: Disk quota exceeded
fallocate: /mnt/data10: fallocate failed: Disk quota exceeded
fallocate: /mnt/data11: fallocate failed: Disk quota exceeded
fallocate: /mnt/data12: fallocate failed: Disk quota exceeded
fallocate: /mnt/data13: fallocate failed: Disk quota exceeded
fallocate: /mnt/data14: fallocate failed: Disk quota exceeded
fallocate: /mnt/data15: fallocate failed: Disk quota exceeded
fallocate: /mnt/data16: fallocate failed: Disk quota exceeded
fallocate: /mnt/data17: fallocate failed: Disk quota exceeded
fallocate: /mnt/data18: fallocate failed: Disk quota exceeded
fallocate: /mnt/data19: fallocate failed: Disk quota exceeded
	# sync
	# btrfs qgroup show -pcre /mnt
qgroupid rfer    excl    max_rfer max_excl parent  child
-------- ----    ----    -------- -------- ------  -----
0/5      9453568 9453568 0        10485760 ---     ---

Reported-by: Cyril SCETBON <cyril.scetbon@free.fr>
Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:52:47 -07:00
Dongsheng Yang 4087cf24ae Btrfs: qgroup: cleanup, remove an unsued parameter in btrfs_create_qgroup().
Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:52:44 -07:00
Dongsheng Yang 03477d945f btrfs: qgroup: fix limit args override whole limit struct
btrfs_limit_group use arg limit to override the old qgroup_limit of
corresponding qgroup. However, we should override part of old qgroup_limit
according to the bit which has been set in arg limit.

Signed-off-by: Fan Chengniang <fancn.fnst@cn.fujitsu.com>
Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:52:43 -07:00
Dongsheng Yang d3001ed3a8 btrfs: qgroup: update limit info in function btrfs_run_qgroups().
When we commit_transaction(), qgroups in btree should be updated.
But, limit info is not considered currently. It will cause a problem
when a qgroup of a snapshot inherit the limit info from srcqgroup,
then there is an inconsistency.

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:52:42 -07:00
Dongsheng Yang 1510e71c62 btrfs: qgroup: consolidate the parameter of fucntion update_qgroup_limit_item().
Cleanup: Change the parameter of update_qgroup_limit_item() to the family of
update_qgroup_xxx_item().

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:52:41 -07:00
Dongsheng Yang e8c8541ac3 btrfs: qgroup: update qgroup in memory at the same time when we update it in btree.
When we call btrfs_qgroup_inherit() with BTRFS_QGROUP_INHERIT_SET_LIMITS,
btrfs will update the limit info of qgroup in btree but forget to update
the qgroup in rbtree at the same time. It obviousely will cause an inconsistency.

This patch fix it by updating the rbtree at the same time.

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:52:40 -07:00
Dongsheng Yang 3eeb4d597e btrfs: qgroup: inherit limit info from srcgroup in creating snapshot.
Currently, when we snapshot a subvol, snapshot will not copy the limits
from srcqgroup.

This patch make the qgroup in snapshot inherit the limit info when create
a snapshot.

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:52:38 -07:00
Filipe Manana bf69196045 Btrfs: change the insertion criteria for the qgroup operations rbtree
After looking at Liu Bo's recent patch (titled
"Btrfs: fix comp_oper to get right order") I realized the search made by
qgroup_oper_exists() was buggy because its rbtree navigation comparison
function, comp_oper_exist(), only looks at the fields bytenr and ref_root
of a tree node, ignoring the seq field completely. This was wrong because
when we insert a node into the rbtree we use comp_oper(), which takes a
decision based first on bytenr, then on seq and then on the ref_root field.
That means qgroup_oper_exists() could miss the fact that at least one
operation with given bytenr and ref_root exists.

Consider the following simple example of a 3 nodes qgroup operations
rbtree (created using comp_oper before this patch), where each node's key
is a tuple with the shape (bytenr, seq, ref_root, op):

                          [ (4096, 2, 20, op X) ]
                         /                       \
                        /                         \
   [ (4096, 1, 5, op Y) ]                         [ (4096, 3, 10, op Z) ]

qgroup_oper_exists() when called to search for an existing operation for
bytenr 4096 and ref root 10 wouldn't find anything because it would go to
the left subtree instead of the right subtree, since comp_oper_exits()
ignores the seq field completely.

Fix this by changing the insertion navigation function to use the ref_root
field right after using the bytenr field and before using the seq field,
so that qgroup_oper_exists() / comp_oper_exist() work as expected.

This patch applies on top of the patch mentioned above from Liu.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-03-26 17:55:52 -07:00
Chris Mason fc4c3c872f Merge branch 'cleanups-post-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.1
Signed-off-by: Chris Mason <clm@fb.com>

Conflicts:
	fs/btrfs/disk-io.c
2015-03-25 10:52:48 -07:00
Chris Mason 9deed229fa Merge branch 'cleanups-for-4.1-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.1 2015-03-25 10:43:16 -07:00
Liu Bo 48da5f0a4c Btrfs: fix comp_oper to get right order
Case (oper1->seq > oper2->seq) should differ with case (oper1->seq < oper2->seq).

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-03-13 13:46:59 -07:00
David Sterba 3284da7b7b btrfs: use explicit initializer for seq_elem
Using {} as initializer for struct seq_elem does not properly initialize
the list_head member, but it currently works because it gets set through
btrfs_get_tree_mod_seq if 'seq' is 0.

Signed-off-by: David Sterba <dsterba@suse.cz>
2015-03-03 17:23:59 +01:00
Daniel Dressler 01d58472a8 Btrfs: disk-io: replace root args iff only fs_info used
This is the 3rd independent patch of a larger project to cleanup btrfs's
internal usage of btrfs_root. Many functions take btrfs_root only to
grab the fs_info struct.

By requiring a root these functions cause programmer overhead. That
these functions can accept any valid root is not obvious until
inspection.

This patch reduces the specificity of such functions to accept the
fs_info directly.

These patches can be applied independently and thus are not being
submitted as a patch series. There should be about 26 patches by the
project's completion. Each patch will cleanup between 1 and 34 functions
apiece.  Each patch covers a single file's functions.

This patch affects the following function(s):
  1) csum_tree_block
  2) csum_dirty_buffer
  3) check_tree_block_fsid
  4) btrfs_find_tree_block
  5) clean_tree_block

Signed-off-by: Daniel Dressler <danieru.dressler@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2015-02-16 18:48:43 +01:00
Yang Dongsheng 0ee13fe28c btrfs: qgroup: move WARN_ON() to the correct location.
In function qgroup_excl_accounting(), we need to WARN when
qg->excl is less than what we want to free, same to child
and parents. But currently, for parent qgroup, the WARN_ON()
is located after freeing qg->excl. It will WARN out even we
free it normally.

This patch move this WARN_ON() before freeing qg->excl.

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Reviewed-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-01-21 18:22:37 -08:00
David Sterba fccb84c94a btrfs: move checks for DUMMY_ROOT into a helper
Signed-off-by: David Sterba <dsterba@suse.cz>
2014-10-02 17:30:33 +02:00
Mark Fasheh 0b4699dcb6 btrfs: don't go readonly on existing qgroup items
btrfs_drop_snapshot() leaves subvolume qgroup items on disk after
completion. This can cause problems with snapshot creation. If a new
snapshot tries to claim the deleted subvolumes id, btrfs will get -EEXIST
from add_qgroup_item() and go read-only. The following commands will
reproduce this problem (assume btrfs is on /dev/sda and is mounted at
/btrfs)

mkfs.btrfs -f /dev/sda
mount -t btrfs /dev/sda /btrfs/
btrfs quota enable /btrfs/
btrfs su sna /btrfs/ /btrfs/snap
btrfs su de /btrfs/snap
sleep 45
umount /btrfs/
mount -t btrfs /dev/sda /btrfs/

We can fix this by catching -EEXIST in add_qgroup_item() and
initializing the existing items. We have the problem of orphaned
relation items being on disk from an old snapshot but that is outside
the scope of this patch.

Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:38:19 -07:00
Mark Fasheh d3982100ba btrfs: add trace for qgroup accounting
We want this to debug qgroup changes on live systems.

Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:37:50 -07:00
David Sterba 707e8a0715 btrfs: use nodesize everywhere, kill leafsize
The nodesize and leafsize were never of different values. Unify the
usage and make nodesize the one. Cleanup the redundant checks and
helpers.

Shaves a few bytes from .text:

  text    data     bss     dec     hex filename
852418   24560   23112  900090   dbbfa btrfs.ko.before
851074   24584   23112  898770   db6d2 btrfs.ko.after

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:37:14 -07:00
Liu Bo 9e0af23764 Btrfs: fix task hang under heavy compressed write
This has been reported and discussed for a long time, and this hang occurs in
both 3.15 and 3.16.

Btrfs now migrates to use kernel workqueue, but it introduces this hang problem.

Btrfs has a kind of work queued as an ordered way, which means that its
ordered_func() must be processed in the way of FIFO, so it usually looks like --

normal_work_helper(arg)
    work = container_of(arg, struct btrfs_work, normal_work);

    work->func() <---- (we name it work X)
    for ordered_work in wq->ordered_list
            ordered_work->ordered_func()
            ordered_work->ordered_free()

The hang is a rare case, first when we find free space, we get an uncached block
group, then we go to read its free space cache inode for free space information,
so it will

file a readahead request
    btrfs_readpages()
         for page that is not in page cache
                __do_readpage()
                     submit_extent_page()
                           btrfs_submit_bio_hook()
                                 btrfs_bio_wq_end_io()
                                 submit_bio()
                                 end_workqueue_bio() <--(ret by the 1st endio)
                                      queue a work(named work Y) for the 2nd
                                      also the real endio()

So the hang occurs when work Y's work_struct and work X's work_struct happens
to share the same address.

A bit more explanation,

A,B,C -- struct btrfs_work
arg   -- struct work_struct

kthread:
worker_thread()
    pick up a work_struct from @worklist
    process_one_work(arg)
	worker->current_work = arg;  <-- arg is A->normal_work
	worker->current_func(arg)
		normal_work_helper(arg)
		     A = container_of(arg, struct btrfs_work, normal_work);

		     A->func()
		     A->ordered_func()
		     A->ordered_free()  <-- A gets freed

		     B->ordered_func()
			  submit_compressed_extents()
			      find_free_extent()
				  load_free_space_inode()
				      ...   <-- (the above readhead stack)
				      end_workqueue_bio()
					   btrfs_queue_work(work C)
		     B->ordered_free()

As if work A has a high priority in wq->ordered_list and there are more ordered
works queued after it, such as B->ordered_func(), its memory could have been
freed before normal_work_helper() returns, which means that kernel workqueue
code worker_thread() still has worker->current_work pointer to be work
A->normal_work's, ie. arg's address.

Meanwhile, work C is allocated after work A is freed, work C->normal_work
and work A->normal_work are likely to share the same address(I confirmed this
with ftrace output, so I'm not just guessing, it's rare though).

When another kthread picks up work C->normal_work to process, and finds our
kthread is processing it(see find_worker_executing_work()), it'll think
work C as a collision and skip then, which ends up nobody processing work C.

So the situation is that our kthread is waiting forever on work C.

Besides, there're other cases that can lead to deadlock, but the real problem
is that all btrfs workqueue shares one work->func, -- normal_work_helper,
so this makes each workqueue to have its own helper function, but only a
wraper pf normal_work_helper.

With this patch, I no long hit the above hang.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-08-24 07:17:02 -07:00
Eric Sandeen a3c108950d btrfs: fix leak in qgroup_subtree_accounting() error path
Coverity pointed this out; in the newly added
qgroup_subtree_accounting(), if btrfs_find_all_roots()
returns an error, we leak at least the parents pointer,
and possibly the roots pointer, depending on what failure
occurs.

If btrfs_find_all_roots() returns an error, we need to
free up all allocations before we return.  "roots" is
initialized to NULL, so it should be safe to free
it unconditionally (ulist_free() handles that case).

Cc: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Chris Mason <clm@fb.com>
2014-08-21 07:55:29 -07:00
Mark Fasheh f90e579c2b btrfs: correctly handle return from ulist_add
ulist_add() can return '1' on sucess, which qgroup_subtree_accounting()
doesn't take into account. As a result, that value can be bubbled up to
callers, causing an error to be printed. Fix this by only returning the
value of ulist_add() when it indicates an error.

Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Chris Mason <clm@fb.com>
2014-08-15 07:43:16 -07:00
Mark Fasheh 1152651a08 btrfs: qgroup: account shared subtrees during snapshot delete
During its tree walk, btrfs_drop_snapshot() will skip any shared
subtrees it encounters. This is incorrect when we have qgroups
turned on as those subtrees need to have their contents
accounted. In particular, the case we're concerned with is when
removing our snapshot root leaves the subtree with only one root
reference.

In those cases we need to find the last remaining root and add
each extent in the subtree to the corresponding qgroup exclusive
counts.

This patch implements the shared subtree walk and a new qgroup
operation, BTRFS_QGROUP_OPER_SUB_SUBTREE. When an operation of
this type is encountered during qgroup accounting, we search for
any root references to that extent and in the case that we find
only one reference left, we go ahead and do the math on it's
exclusive counts.

Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-08-15 07:43:14 -07:00
Eric Sandeen d737278091 btrfs: free ulist in qgroup_shared_accounting() error path
If tmp = ulist_alloc(GFP_NOFS) fails, we return without
freeing the previously allocated qgroups = ulist_alloc(GFP_NOFS)
and cause a memory leak.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-13 09:52:26 -07:00
Josef Bacik 2a10840945 Btrfs: free tmp ulist for qgroup rescan
Memory leaks are bad mmkay?

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:20:55 -07:00
Josef Bacik faa2dbf004 Btrfs: add sanity tests for new qgroup accounting code
This exercises the various parts of the new qgroup accounting code.  We do some
basic stuff and do some things with the shared refs to make sure all that code
works.  I had to add a bunch of infrastructure because I needed to be able to
insert items into a fake tree without having to do all the hard work myself,
hopefully this will be usefull in the future.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:20:49 -07:00
Josef Bacik fcebe4562d Btrfs: rework qgroup accounting
Currently qgroups account for space by intercepting delayed ref updates to fs
trees.  It does this by adding sequence numbers to delayed ref updates so that
it can figure out how the tree looked before the update so we can adjust the
counters properly.  The problem with this is that it does not allow delayed refs
to be merged, so if you say are defragging an extent with 5k snapshots pointing
to it we will thrash the delayed ref lock because we need to go back and
manually merge these things together.  Instead we want to process quota changes
when we know they are going to happen, like when we first allocate an extent, we
free a reference for an extent, we add new references etc.  This patch
accomplishes this by only adding qgroup operations for real ref changes.  We
only modify the sequence number when we need to lookup roots for bytenrs, this
reduces the amount of churn on the sequence number and allows us to merge
delayed refs as we add them most of the time.  This patch encompasses a bunch of
architectural changes

1) qgroup ref operations: instead of tracking qgroup operations through the
delayed refs we simply add new ref operations whenever we notice that we need to
when we've modified the refs themselves.

2) tree mod seq:  we no longer have this separation of major/minor counters.
this makes the sequence number stuff much more sane and we can remove some
locking that was needed to protect the counter.

3) delayed ref seq: we now read the tree mod seq number and use that as our
sequence.  This means each new delayed ref doesn't have it's own unique sequence
number, rather whenever we go to lookup backrefs we inc the sequence number so
we can make sure to keep any new operations from screwing up our world view at
that given point.  This allows us to merge delayed refs during runtime.

With all of these changes the delayed ref stuff is a little saner and the qgroup
accounting stuff no longer goes negative in some cases like it was before.
Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:20:48 -07:00
Qu Wenruo d458b0540e btrfs: Cleanup the "_struct" suffix in btrfs_workequeue
Since the "_struct" suffix is mainly used for distinguish the differnt
btrfs_work between the original and the newly created one,
there is no need using the suffix since all btrfs_workers are changed
into btrfs_workqueue.

Also this patch fixed some codes whose code style is changed due to the
too long "_struct" suffix.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:16 -04:00
Qu Wenruo fc97fab0ea btrfs: Replace fs_info->qgroup_rescan_worker workqueue with btrfs_workqueue.
Replace the fs_info->qgroup_rescan_worker with the newly created
btrfs_workqueue.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:13 -04:00
Josef Bacik 3a6d75e846 Btrfs: fix qgroup rescan to work with skinny metadata
Could have sworn I fixed this before but apparently not.  This makes us pass
btrfs/022 with skinny metadata enabled.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:27 -08:00
Frank Holton efe120a067 Btrfs: convert printk to btrfs_ and fix BTRFS prefix
Convert all applicable cases of printk and pr_* to the btrfs_* macros.

Fix all uses of the BTRFS prefix.

Signed-off-by: Frank Holton <fholton@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:05 -08:00
Valentina Giusti a3df41ee37 btrfs: fix unused variables in qgroup.c
Use otherwise unused local variables slot in update_qgroup_limit_item and
in update_qgroup_info_item, and remove unused variable ins from
btrfs_qgroup_account_ref.

Signed-off-by: Valentina Giusti <valentina.giusti@microon.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:19:35 -08:00
Geert Uytterhoeven c1c9ff7c94 Btrfs: Remove superfluous casts from u64 to unsigned long long
u64 is "unsigned long long" on all architectures now, so there's no need to
cast it when formatting it using the "ll" length modifier.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-09-01 08:16:08 -04:00
Wang Shilong b006b2e4f9 Btrfs: remove reduplicate check when disabling quota
We have checked 'quota_root' with qgroup_ioctl_lock held before,So
here the check is reduplicate, remove it.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-09-01 08:15:47 -04:00
Wang Shilong e685da14af Btrfs: move btrfs_free_qgroup_config() out of spin_lock and fix comments
btrfs_free_qgroup_config() is not only called by open/close_ctree(),but
also btrfs_disable_quota().And for btrfs_disable_quota(),we have set
'quota_root' to be null before calling btrfs_free_qgroup_config(),so it
is safe to cleanup in-memory structures without lock held.

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>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-09-01 08:15:46 -04:00
Wang Shilong 4082bd3d73 Btrfs: fix oops when writing dirty qgroups to disk
When disabling quota, we should clear out list 'dirty_qgroups',otherwise,
we will get oops if enabling quota again. Fix this by abstracting similar
code from del_qgroup_rb().

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-09-01 08:15:45 -04:00
Wang Shilong 1e7bac1ef7 Btrfs: set qgroup_ulist to be null after calling ulist_free()
We call ulist_free(qgroup_ulist) in btrfs_free_qgroup_config(),
and btrfs_free_qgroup_config() may be called in two cases:

(1)umount filesystem
(2)disabling quota

However, if we firstly disable quota and then umount filesystem,
a double free happens. Fix it.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-09-01 07:57:36 -04:00
Jan Schmidt b382a324b6 Btrfs: fix qgroup rescan resume on mount
When called during mount, we cannot start the rescan worker thread until
open_ctree is done. This commit restuctures the qgroup rescan internals to
enable a clean deferral of the rescan resume operation.

First of all, the struct qgroup_rescan is removed, saving us a malloc and
some initialization synchronizations problems. Its only element (the worker
struct) now lives within fs_info just as the rest of the rescan code.

Then setting up a rescan worker is split into several reusable stages.
Currently we have three different rescan startup scenarios:
	(A) rescan ioctl
	(B) rescan resume by mount
	(C) rescan by quota enable

Each case needs its own combination of the four following steps:
	(1) set the progress [A, C: zero; B: state of umount]
	(2) commit the transaction [A]
	(3) set the counters [A, C: zero; B: state of umount]
	(4) start worker [A, B, C]

qgroup_rescan_init does step (1). There's no extra function added to commit
a transaction, we've got that already. qgroup_rescan_zero_tracking does
step (3). Step (4) is nothing more than a call to the generic
btrfs_queue_worker.

We also get rid of a double check for the rescan progress during
btrfs_qgroup_account_ref, which is no longer required due to having step 2
from the list above.

As a side effect, this commit prepares to move the rescan start code from
btrfs_run_qgroups (which is run during commit) to a less time critical
section.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-06-14 11:30:10 -04:00
Jan Schmidt eb1716af88 Btrfs: avoid double free of fs_info->qgroup_ulist
When btrfs_read_qgroup_config or btrfs_quota_enable return non-zero, we've
already freed the fs_info->qgroup_ulist. The final btrfs_free_qgroup_config
called from quota_disable makes another ulist_free(fs_info->qgroup_ulist)
call.

We set fs_info->qgroup_ulist to NULL on the mentioned error paths, turning
the ulist_free in btrfs_free_qgroup_config into a noop.

Cc: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-06-14 11:30:08 -04:00
Jan Schmidt 4373519db4 Btrfs: fix memory patcher through fs_info->qgroup_ulist
Commit 5b7c665e introduced fs_info->qgroup_ulist, that is allocated during
btrfs_read_qgroup_config and meant to be used later by the qgroup accounting
code. However, it is always freed before btrfs_read_qgroup_config returns,
becuase the commit mentioned above adds a check for (ret), where a check
for (ret < 0) would have been the right choice. This commit fixes the check.

Cc: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-06-14 11:30:07 -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
Jan Schmidt 3d7b5a2882 Btrfs: automatic rescan after "quota enable" command
When qgroup tracking is enabled, we do an automatic cycle of the new rescan
mechanism.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06 15:55:20 -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 46b665ceb1 Btrfs: split btrfs_qgroup_account_ref into four functions
The function is separated into a preparation part and the three accounting
steps mentioned in the qgroups documentation. The goal is to make steps two
and three usable by the rescan functionality. A side effect is that the
function is restructured into readable subunits.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06 15:55:18 -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
Wang Shilong 534e6623b7 Btrfs: add all ioctl checks before user change for quota operations
Since all the quota configurations are loaded in memory, and we can
have ioctl checks before operating in the disk. It is safe to do such
things because qgroup_ioctl_lock is held outside.

Without these extra checks firstly, it should be ok to do user change
for quota operations. For example:

if we want to add an existed qgroup, we will do:
	->add_qgroup_item()
		->add_qgroup_rb()

add_qgroup_item() will return -EEXIST to us, however, qgroups are all
in memory, why not check them in memory firstly.

Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06 15:54:59 -04:00
Wang Shilong 3c97185c65 Btrfs: fix missing check about ulist_add() in qgroup.c
ulist_add() may return -ENOMEM, fix missing check about
return value.

Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06 15:54:58 -04:00
Wang Shilong b4fcd6be6b Btrfs: fix confusing edquot happening case
Step to reproduce:
	mkfs.btrfs <disk>
	mount <disk> <mnt>
	dd if=/dev/zero of=/<mnt>/data bs=1M count=10
	sync
	btrfs quota enable <mnt>
	btrfs qgroup create 0/5 <mnt>
	btrfs qgroup limit 5M 0/5 <mnt>
	rm -f /<mnt>/data
	sync
	btrfs qgroup show <mnt>
	dd if=/dev/zero of=data bs=1M count=1

>From the perspective of users, qgroup's referenced or exclusive
is negative,but user can not continue to write data! a workaround
way is to cast u64 to s64 when doing qgroup reservation.

Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Reviewed-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06 15:54:51 -04:00
Wang Shilong ddb47afa50 Btrfs: fix a warning when updating qgroup limit
Step to reproduce:
	mkfs.btrfs <disk>
	mount <disk> <mnt>
	btrfs quota enable <mnt>
	btrfs qgroup limit 0/1 <mnt>
	dmesg

If the relative qgroup dosen't exist, flag 'BTRFS_QGROUP_STATUS_
FLAG_INCONSISTENT' will be set, and print the noise message.
This is wrong, we can just move find_qgroup_rb() before
update_qgroup_limit_item().this dosen't change the logic of the
function. But it can avoid unnecessary noise message and wrong set of flag.

Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06 15:54:41 -04:00
Wang Shilong 3f5e2d3b38 Btrfs: fix missing check in the btrfs_qgroup_inherit()
The original code forgot to check 'inherit', we should
gurantee that all the qgroups in the struct 'inherit' exist.

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 15:54:40 -04:00
Wang Shilong b7fef4f593 Btrfs: fix missing check before creating a qgroup relation
Step to reproduce:
		mkfs.btrfs <disk>
		mount <disk> <mnt>
		btrfs quota enable <mnt>
		btrfs qgroup assign 0/1 1/1 <mnt>
		umount <mnt>
		btrfs-debug-tree <disk> | grep QGROUP
If we want to add a qgroup relation, we should gurantee that
'src' and 'dst' exist, otherwise, such qgroup relation should
not be allowed to create.

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 15:54:39 -04:00
Wang Shilong 58400fce5a Btrfs: remove some unnecessary spin_lock usages
We use mutex lock to protect all the user change operations.
So when we are calling find_qgroup_rb() to check whether qgroup
exists, we don't have to hold spin_lock.

Besides, when enabling/disabling quota, it must be single thread
when operations come here. spin lock must be firstly used to
clear quota_root when disabling quota, while enabling quota, spin
lock must be used to complete the last assign work.

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 15:54:39 -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
Wang Shilong 7708f029dc Btrfs: creating the subvolume qgroup automatically when enabling quota
Creating the subvolume/snapshots(including root subvolume) qgroup
auotomatically when enabling quota.

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 15:54:37 -04:00
Wang Shilong c9a9dbf2cb Btrfs: fix a warning when disabling quota
Steps to reproduce:
	mkfs.btrfs <disk>
	mount <disk> <mnt>
	btrfs quota enable <mnt>
	btrfs sub create <mnt>/subv

	i=1
	while [ $i -le 10000 ]
	do
		dd if=/dev/zero of=<mnt>/subv/data_$i bs=1K count=1
		i=$(($i+1))
		if [ $i -eq 500 ]
		then
			btrfs quota disable $mnt
		fi
	done
	dmesg
Obviously, this warn_on() is unnecessary, and it will be easily triggered.
Just remove it.

Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06 15:54:28 -04:00
Wang Shilong a7975026ff Btrfs: fix double free in the btrfs_qgroup_account_ref()
The function btrfs_find_all_roots is responsible to allocate
memory for 'roots' and free it if errors happen,so the caller should not
free it again since the work has been done.

Besides,'tmp' is allocated after the function btrfs_find_all_roots,
so we can return directly if btrfs_find_all_roots() fails.

Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-03-28 09:51:29 -04:00
Wang Shilong 720f1e2060 Btrfs: return as soon as possible when edquot happens
If one of qgroup fails to reserve firstly, we should return immediately,
it is unnecessary to continue check.

Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-03-14 14:57:29 -04:00
Wang Shilong 235fdb8ef2 Btrfs: remove reduplicate check about root in the function btrfs_clean_quota_tree
The check work has been done just before the function btrfs_clean_quota_tree
is called, it is not necessary to check it again, remove it.

Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-03-01 10:13:04 -05:00
Wang Shilong 84cbe2f725 Btrfs: return ENOMEM rather than use BUG_ON when btrfs_alloc_path fails
Return ENOMEM rather trigger BUG_ON, fix it.

Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: Zach Brown <zab@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-03-01 10:13:04 -05:00
Wang Shilong 06b3a860dc Btrfs: fix missing deleted items in btrfs_clean_quota_tree
Steps to reproduce:

	i=0
	ncases=100

	mkfs.btrfs <disk>
	mount <disk> <mnt>
	btrfs quota enable <mnt>
	btrfs qgroup create 2/1 <mnt>
	while [ $i -le $ncases ]
	do
		btrfs qgroup create 1/$i <mnt>
		btrfs qgroup assign 1/$i 2/1 <mnt>
		i=$(($i+1))
	done

	btrfs quota disable <mnt>
	umount <mnt>
	btrfsck <mnt>

You can also use the commands:
	btrfs-debug-tree <disk> | grep QGROUP

You will find there are still items existed.The reasons why this happens
is because the original code just checks slots[0]==0 and returns.
We try to fix it by deleting the leaf one by one.

Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-03-01 10:13:03 -05:00
Wang Shilong 683cebda90 Btrfs: fix missing check before disabling quota
The original code forget to check whether quota has been disabled firstly,
and it will return 'EINVAL' and return error to users if quota has been
disabled,it will be unfriendly and confusing for users to see that.
So just return directly if quota has been disabled.

Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Cc: Arne Jansen <sensille@gmx.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20 13:00:07 -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
Arne Jansen 2cf6870396 Btrfs: prevent qgroup destroy when there are still relations
Currently you can just destroy a qgroup even though it is in use by other qgroups
or has qgroups assigned to it. This patch prevents destruction of qgroups unless
they are completely unused. Otherwise destroy will return EBUSY.

Reported-by: Eric Hopper <hopper@omnifarious.org>
Signed-off-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-01-21 20:18:11 -05:00
Arne Jansen ff24858c65 Btrfs: ignore orphan qgroup relations
If a qgroup that has still assignments is deleted by the user, the corresponding
relations are left in the tree. This leads to an unmountable filesystem.
With this patch, those relations are simple ignored.

Reported-by: Eric Hopper <hopper@omnifarious.org>
Signed-off-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-01-21 20:18:11 -05:00
Tsutomu Itoh 5b7ff5b3c4 Btrfs: fix memory leak in btrfs_quota_enable()
We should free quota_root before returning from the error
handling code.

Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
2012-10-25 15:45:43 -04:00
Tsutomu Itoh 3d6b5c3b5c Btrfs: check return value of ulist_alloc() properly
ulist_alloc() has the possibility of returning NULL.
So, it is necessary to check the return value.

Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
2012-10-01 15:19:14 -04:00
Jan Schmidt 995e01b7af Btrfs: fix gcc warnings for 32bit compiles
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-10-01 15:19:01 -04:00
Alexander Block 34d73f54e2 Btrfs: make aux field of ulist 64 bit
Btrfs send/receive uses the aux field to store inode numbers. On
32 bit machines this may become a problem.

Also fix all users of ulist_add and ulist_add_merged.

Reported-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01 15:18:53 -04:00
Chris Mason f3a87f1b0c Revert "Btrfs: fix some error codes in btrfs_qgroup_inherit()"
This reverts commit 5986802c2f.

Both paths are not error paths but regular cases where non-qgroup
subvols are involved.

Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-09-14 20:06:30 -04:00
Dan Carpenter 57a5a88203 Btrfs: checking for NULL instead of IS_ERR
add_qgroup_rb() never returns NULL, only error pointers.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
2012-08-28 16:53:25 -04:00
Dan Carpenter 5986802c2f Btrfs: fix some error codes in btrfs_qgroup_inherit()
These are returning zero when it should be returning a negative error
code.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
2012-08-28 16:53:24 -04:00
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