6.6-stable review patch. If anyone has any objections, please let me know.
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From: Boris Burkov boris@bur.io
commit a8df35619948bd8363d330c20a90c9a7fbff28c0 upstream.
If a subvolume still exists, forbid deleting its qgroup 0/subvolid. This behavior generally leads to incorrect behavior in squotas and doesn't have a legitimate purpose.
Fixes: cecbb533b5fc ("btrfs: record simple quota deltas in delayed refs") CC: stable@vger.kernel.org # 5.4+ Reviewed-by: Qu Wenruo wqu@suse.com Signed-off-by: Boris Burkov boris@bur.io Reviewed-by: David Sterba dsterba@suse.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/btrfs/qgroup.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+)
--- a/fs/btrfs/qgroup.c +++ b/fs/btrfs/qgroup.c @@ -1659,6 +1659,15 @@ out: return ret; }
+static bool qgroup_has_usage(struct btrfs_qgroup *qgroup) +{ + return (qgroup->rfer > 0 || qgroup->rfer_cmpr > 0 || + qgroup->excl > 0 || qgroup->excl_cmpr > 0 || + qgroup->rsv.values[BTRFS_QGROUP_RSV_DATA] > 0 || + qgroup->rsv.values[BTRFS_QGROUP_RSV_META_PREALLOC] > 0 || + qgroup->rsv.values[BTRFS_QGROUP_RSV_META_PERTRANS] > 0); +} + int btrfs_remove_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid) { struct btrfs_fs_info *fs_info = trans->fs_info; @@ -1678,6 +1687,11 @@ int btrfs_remove_qgroup(struct btrfs_tra goto out; }
+ if (is_fstree(qgroupid) && qgroup_has_usage(qgroup)) { + ret = -EBUSY; + goto out; + } + /* Check if there are no children of this qgroup */ if (!list_empty(&qgroup->members)) { ret = -EBUSY;