btrfs: correctly handle return from ulist_add

ulist_add() can return '1' on sucess, which qgroup_subtree_accounting()
doesn't take into account. As a result, that value can be bubbled up to
callers, causing an error to be printed. Fix this by only returning the
value of ulist_add() when it indicates an error.

Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Chris Mason <clm@fb.com>

1 files changed, 9 insertions, 4 deletions

diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index 65b62c467e28..b497498484be 100644
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -1959,6 +1959,7 @@ static int qgroup_subtree_accounting(struct btrfs_trans_handle *trans,
         struct btrfs_qgroup_list *glist;
         struct ulist *parents;
         int ret = 0;
+        int err;
         struct btrfs_qgroup *qg;
         u64 root_obj = 0;
         struct seq_list elem = {};
@@ -2013,10 +2014,12 @@ static int qgroup_subtree_accounting(struct btrfs_trans_handle *trans,
          * while adding parents of the parents to our ulist.
          */
         list_for_each_entry(glist, &qg->groups, next_group) {
-                ret = ulist_add(parents, glist->group->qgroupid,
+                err = ulist_add(parents, glist->group->qgroupid,
                                 ptr_to_u64(glist->group), GFP_ATOMIC);
-                if (ret < 0)
+                if (err < 0) {
+                        ret = err;
                         goto out_unlock;
+                }
         }
 
         ULIST_ITER_INIT(&uiter);
@@ -2028,10 +2031,12 @@ static int qgroup_subtree_accounting(struct btrfs_trans_handle *trans,
 
                 /* Add any parents of the parents */
                 list_for_each_entry(glist, &qg->groups, next_group) {
-                        ret = ulist_add(parents, glist->group->qgroupid,
+                        err = ulist_add(parents, glist->group->qgroupid,
                                         ptr_to_u64(glist->group), GFP_ATOMIC);
-                        if (ret < 0)
+                        if (err < 0) {
+                                ret = err;
                                 goto out_unlock;
+                        }
                 }
         }