diff options
author | Filipe Manana <fdmanana@suse.com> | 2023-05-04 14:04:18 +0300 |
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committer | David Sterba <dsterba@suse.com> | 2023-05-09 23:08:05 +0300 |
commit | 0004ff15ea26015a0a3a6182dca3b9d1df32e2b7 (patch) | |
tree | 136138327cb71645b4dfd2828e2585b01b66f98b | |
parent | c87f318e6f47696b4040b58f460d5c17ea0280e6 (diff) | |
download | linux-0004ff15ea26015a0a3a6182dca3b9d1df32e2b7.tar.xz |
btrfs: fix space cache inconsistency after error loading it from disk
When loading a free space cache from disk, at __load_free_space_cache(),
if we fail to insert a bitmap entry, we still increment the number of
total bitmaps in the btrfs_free_space_ctl structure, which is incorrect
since we failed to add the bitmap entry. On error we then empty the
cache by calling __btrfs_remove_free_space_cache(), which will result
in getting the total bitmaps counter set to 1.
A failure to load a free space cache is not critical, so if a failure
happens we just rebuild the cache by scanning the extent tree, which
happens at block-group.c:caching_thread(). Yet the failure will result
in having the total bitmaps of the btrfs_free_space_ctl always bigger
by 1 then the number of bitmap entries we have. So fix this by having
the total bitmaps counter be incremented only if we successfully added
the bitmap entry.
Fixes: a67509c30079 ("Btrfs: add a io_ctl struct and helpers for dealing with the space cache")
Reviewed-by: Anand Jain <anand.jain@oracle.com>
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
-rw-r--r-- | fs/btrfs/free-space-cache.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c index d84cef89cdff..cf98a3c05480 100644 --- a/fs/btrfs/free-space-cache.c +++ b/fs/btrfs/free-space-cache.c @@ -870,15 +870,16 @@ static int __load_free_space_cache(struct btrfs_root *root, struct inode *inode, } spin_lock(&ctl->tree_lock); ret = link_free_space(ctl, e); - ctl->total_bitmaps++; - recalculate_thresholds(ctl); - spin_unlock(&ctl->tree_lock); if (ret) { + spin_unlock(&ctl->tree_lock); btrfs_err(fs_info, "Duplicate entries in free space cache, dumping"); kmem_cache_free(btrfs_free_space_cachep, e); goto free_cache; } + ctl->total_bitmaps++; + recalculate_thresholds(ctl); + spin_unlock(&ctl->tree_lock); list_add_tail(&e->list, &bitmaps); } |