diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 6137f06..54f2b1d 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -2501,6 +2501,7 @@
 	u64 nr = 0;
 	u64 cur_byte;
 	u64 old_size;
+	unsigned long rem;
 	struct btrfs_block_group_cache *cache;
 	struct btrfs_block_group_item *item;
 	struct btrfs_fs_info *info = root->fs_info;
@@ -2538,7 +2539,8 @@
 				      struct btrfs_block_group_item);
 
 		btrfs_set_disk_block_group_used(leaf, item, 0);
-		if (nr % 3) {
+		div_long_long_rem(nr, 3, &rem);
+		if (rem) {
 			btrfs_set_disk_block_group_flags(leaf, item,
 						 BTRFS_BLOCK_GROUP_DATA);
 		} else {