btrfs: use helper to set ulist aux from a qgroup

We have a nice helper to do proper casting of a qgroup to a ulist aux
value. And several places that could make use of it.

Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index c8ca548..6b715d6 100644
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -2434,7 +2434,7 @@ static int qgroup_reserve(struct btrfs_root *root, u64 num_bytes, bool enforce,
 	 */
 	ulist_reinit(fs_info->qgroup_ulist);
 	ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
-			(uintptr_t)qgroup, GFP_ATOMIC);
+			qgroup_to_aux(qgroup), GFP_ATOMIC);
 	if (ret < 0)
 		goto out;
 	ULIST_ITER_INIT(&uiter);
@@ -2452,7 +2452,7 @@ static int qgroup_reserve(struct btrfs_root *root, u64 num_bytes, bool enforce,
 		list_for_each_entry(glist, &qg->groups, next_group) {
 			ret = ulist_add(fs_info->qgroup_ulist,
 					glist->group->qgroupid,
-					(uintptr_t)glist->group, GFP_ATOMIC);
+					qgroup_to_aux(glist->group), GFP_ATOMIC);
 			if (ret < 0)
 				goto out;
 		}
@@ -2524,7 +2524,7 @@ void btrfs_qgroup_free_refroot(struct btrfs_fs_info *fs_info,
 
 	ulist_reinit(fs_info->qgroup_ulist);
 	ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
-			(uintptr_t)qgroup, GFP_ATOMIC);
+			qgroup_to_aux(qgroup), GFP_ATOMIC);
 	if (ret < 0)
 		goto out;
 	ULIST_ITER_INIT(&uiter);
@@ -2540,7 +2540,7 @@ void btrfs_qgroup_free_refroot(struct btrfs_fs_info *fs_info,
 		list_for_each_entry(glist, &qg->groups, next_group) {
 			ret = ulist_add(fs_info->qgroup_ulist,
 					glist->group->qgroupid,
-					(uintptr_t)glist->group, GFP_ATOMIC);
+					qgroup_to_aux(glist->group), GFP_ATOMIC);
 			if (ret < 0)
 				goto out;
 		}
@@ -3186,7 +3186,7 @@ static void qgroup_convert_meta(struct btrfs_fs_info *fs_info, u64 ref_root,
 		goto out;
 	ulist_reinit(fs_info->qgroup_ulist);
 	ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
-		       (uintptr_t)qgroup, GFP_ATOMIC);
+		       qgroup_to_aux(qgroup), GFP_ATOMIC);
 	if (ret < 0)
 		goto out;
 	ULIST_ITER_INIT(&uiter);
@@ -3203,7 +3203,7 @@ static void qgroup_convert_meta(struct btrfs_fs_info *fs_info, u64 ref_root,
 		list_for_each_entry(glist, &qg->groups, next_group) {
 			ret = ulist_add(fs_info->qgroup_ulist,
 					glist->group->qgroupid,
-					(uintptr_t)glist->group, GFP_ATOMIC);
+					qgroup_to_aux(glist->group), GFP_ATOMIC);
 			if (ret < 0)
 				goto out;
 		}