Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'for-6.9-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
- set correct ram_bytes when splitting ordered extent. This can be
inconsistent on-disk but harmless as it's not used for calculations
and it's only advisory for compression
- fix lockdep splat when taking cleaner mutex in qgroups disable ioctl
- fix missing mutex unlock on error path when looking up sys chunk for
relocation
* tag 'for-6.9-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: set correct ram_bytes when splitting ordered extent
btrfs: take the cleaner_mutex earlier in qgroup disable
btrfs: add missing mutex_unlock in btrfs_relocate_sys_chunks()
+40
-16
+30
-3
fs/btrfs/ioctl.c
+30
-3
fs/btrfs/ioctl.c
···
3758
3758
goto drop_write;
3759
3759
}
3760
3760
3761
-
down_write(&fs_info->subvol_sem);
3762
-
3763
3761
switch (sa->cmd) {
3764
3762
case BTRFS_QUOTA_CTL_ENABLE:
3765
3763
case BTRFS_QUOTA_CTL_ENABLE_SIMPLE_QUOTA:
3764
+
down_write(&fs_info->subvol_sem);
3766
3765
ret = btrfs_quota_enable(fs_info, sa);
3766
+
up_write(&fs_info->subvol_sem);
3767
3767
break;
3768
3768
case BTRFS_QUOTA_CTL_DISABLE:
3769
+
/*
3770
+
* Lock the cleaner mutex to prevent races with concurrent
3771
+
* relocation, because relocation may be building backrefs for
3772
+
* blocks of the quota root while we are deleting the root. This
3773
+
* is like dropping fs roots of deleted snapshots/subvolumes, we
3774
+
* need the same protection.
3775
+
*
3776
+
* This also prevents races between concurrent tasks trying to
3777
+
* disable quotas, because we will unlock and relock
3778
+
* qgroup_ioctl_lock across BTRFS_FS_QUOTA_ENABLED changes.
3779
+
*
3780
+
* We take this here because we have the dependency of
3781
+
*
3782
+
* inode_lock -> subvol_sem
3783
+
*
3784
+
* because of rename. With relocation we can prealloc extents,
3785
+
* so that makes the dependency chain
3786
+
*
3787
+
* cleaner_mutex -> inode_lock -> subvol_sem
3788
+
*
3789
+
* so we must take the cleaner_mutex here before we take the
3790
+
* subvol_sem. The deadlock can't actually happen, but this
3791
+
* quiets lockdep.
3792
+
*/
3793
+
mutex_lock(&fs_info->cleaner_mutex);
3794
+
down_write(&fs_info->subvol_sem);
3769
3795
ret = btrfs_quota_disable(fs_info);
3796
+
up_write(&fs_info->subvol_sem);
3797
+
mutex_unlock(&fs_info->cleaner_mutex);
3770
3798
break;
3771
3799
default:
3772
3800
ret = -EINVAL;
···
3802
3774
}
3803
3775
3804
3776
kfree(sa);
3805
-
up_write(&fs_info->subvol_sem);
3806
3777
drop_write:
3807
3778
mnt_drop_write_file(file);
3808
3779
return ret;
+1
fs/btrfs/ordered-data.c
+1
fs/btrfs/ordered-data.c
+8
-13
fs/btrfs/qgroup.c
+8
-13
fs/btrfs/qgroup.c
···
1342
1342
lockdep_assert_held_write(&fs_info->subvol_sem);
1343
1343
1344
1344
/*
1345
-
* Lock the cleaner mutex to prevent races with concurrent relocation,
1346
-
* because relocation may be building backrefs for blocks of the quota
1347
-
* root while we are deleting the root. This is like dropping fs roots
1348
-
* of deleted snapshots/subvolumes, we need the same protection.
1349
-
*
1350
-
* This also prevents races between concurrent tasks trying to disable
1351
-
* quotas, because we will unlock and relock qgroup_ioctl_lock across
1352
-
* BTRFS_FS_QUOTA_ENABLED changes.
1345
+
* Relocation will mess with backrefs, so make sure we have the
1346
+
* cleaner_mutex held to protect us from relocate.
1353
1347
*/
1354
-
mutex_lock(&fs_info->cleaner_mutex);
1348
+
lockdep_assert_held(&fs_info->cleaner_mutex);
1355
1349
1356
1350
mutex_lock(&fs_info->qgroup_ioctl_lock);
1357
1351
if (!fs_info->quota_root)
···
1367
1373
clear_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags);
1368
1374
btrfs_qgroup_wait_for_completion(fs_info, false);
1369
1375
1376
+
/*
1377
+
* We have nothing held here and no trans handle, just return the error
1378
+
* if there is one.
1379
+
*/
1370
1380
ret = flush_reservations(fs_info);
1371
1381
if (ret)
1372
-
goto out_unlock_cleaner;
1382
+
return ret;
1373
1383
1374
1384
/*
1375
1385
* 1 For the root item
···
1437
1439
btrfs_end_transaction(trans);
1438
1440
else if (trans)
1439
1441
ret = btrfs_commit_transaction(trans);
1440
-
out_unlock_cleaner:
1441
-
mutex_unlock(&fs_info->cleaner_mutex);
1442
-
1443
1442
return ret;
1444
1443
}
1445
1444