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| author | Qu Wenruo | 2017-04-14 02:35:54 +0200 |
|---|---|---|
| committer | David Sterba | 2017-04-18 14:07:27 +0200 |
| commit | 0966a7b1300f953b04b436aa82486d3d1b17c96d (patch) | |
| tree | 918f983ce93ded51f7c8176740cdaee6f1ee7eb6 /fs/btrfs/extent-tree.c | |
| parent | btrfs: Use ktime_get_real_ts for root ctime (diff) | |
| download | kernel-qcow2-linux-0966a7b1300f953b04b436aa82486d3d1b17c96d.tar.gz kernel-qcow2-linux-0966a7b1300f953b04b436aa82486d3d1b17c96d.tar.xz kernel-qcow2-linux-0966a7b1300f953b04b436aa82486d3d1b17c96d.zip | |
btrfs: scrub: Introduce full stripe lock for RAID56
Unlike mirror based profiles, RAID5/6 recovery needs to read out the
whole full stripe.
And if we don't do proper protection, it can easily cause race condition.
Introduce 2 new functions: lock_full_stripe() and unlock_full_stripe()
for RAID5/6.
Which store a rb_tree of mutexes for full stripes, so scrub callers can
use them to lock a full stripe to avoid race.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor comment adjustments ]
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs/extent-tree.c')
| -rw-r--r-- | fs/btrfs/extent-tree.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index e870e60e33bc..e390451c72e6 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -131,6 +131,16 @@ void btrfs_put_block_group(struct btrfs_block_group_cache *cache) if (atomic_dec_and_test(&cache->count)) { WARN_ON(cache->pinned > 0); WARN_ON(cache->reserved > 0); + + /* + * If not empty, someone is still holding mutex of + * full_stripe_lock, which can only be released by caller. + * And it will definitely cause use-after-free when caller + * tries to release full stripe lock. + * + * No better way to resolve, but only to warn. + */ + WARN_ON(!RB_EMPTY_ROOT(&cache->full_stripe_locks_root.root)); kfree(cache->free_space_ctl); kfree(cache); } @@ -9917,6 +9927,7 @@ btrfs_create_block_group_cache(struct btrfs_fs_info *fs_info, btrfs_init_free_space_ctl(cache); atomic_set(&cache->trimming, 0); mutex_init(&cache->free_space_lock); + btrfs_init_full_stripe_locks_tree(&cache->full_stripe_locks_root); return cache; } |