diff options
Diffstat (limited to 'fs/btrfs')
| -rw-r--r-- | fs/btrfs/qgroup.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c index f93354a96909..fc2a7ea26354 100644 --- a/fs/btrfs/qgroup.c +++ b/fs/btrfs/qgroup.c @@ -468,6 +468,7 @@ int btrfs_read_qgroup_config(struct btrfs_fs_info *fs_info) } if (!qgroup) { struct btrfs_qgroup *prealloc; + struct btrfs_root *tree_root = fs_info->tree_root; prealloc = kzalloc(sizeof(*prealloc), GFP_KERNEL); if (!prealloc) { @@ -475,6 +476,25 @@ int btrfs_read_qgroup_config(struct btrfs_fs_info *fs_info) goto out; } qgroup = add_qgroup_rb(fs_info, prealloc, found_key.offset); + /* + * If a qgroup exists for a subvolume ID, it is possible + * that subvolume has been deleted, in which case + * re-using that ID would lead to incorrect accounting. + * + * Ensure that we skip any such subvol ids. + * + * We don't need to lock because this is only called + * during mount before we start doing things like creating + * subvolumes. + */ + if (is_fstree(qgroup->qgroupid) && + qgroup->qgroupid > tree_root->free_objectid) + /* + * Don't need to check against BTRFS_LAST_FREE_OBJECTID, + * as it will get checked on the next call to + * btrfs_get_free_objectid. + */ + tree_root->free_objectid = qgroup->qgroupid + 1; } ret = btrfs_sysfs_add_one_qgroup(fs_info, qgroup); if (ret < 0) |