Patch "btrfs: qgroup: use qgroup_iterator in qgroup_convert_meta()" has been added to the 6.6-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    btrfs: qgroup: use qgroup_iterator in qgroup_convert_meta()

to the 6.6-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     btrfs-qgroup-use-qgroup_iterator-in-qgroup_convert_m.patch
and it can be found in the queue-6.6 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 30924dd2258ba3ce14862a28b3d33a970b66f286
Author: Qu Wenruo <wqu@xxxxxxxx>
Date:   Sat Sep 2 08:13:54 2023 +0800

    btrfs: qgroup: use qgroup_iterator in qgroup_convert_meta()
    
    [ Upstream commit 0913445082496c2b29668ee26521401b273838b8 ]
    
    With the new qgroup_iterator_add() and qgroup_iterator_clean(), we can
    get rid of the ulist and its GFP_ATOMIC memory allocation.
    
    Reviewed-by: Boris Burkov <boris@xxxxxx>
    Signed-off-by: Qu Wenruo <wqu@xxxxxxxx>
    Reviewed-by: David Sterba <dsterba@xxxxxxxx>
    Signed-off-by: David Sterba <dsterba@xxxxxxxx>
    Stable-dep-of: b321a52cce06 ("btrfs: free qgroup pertrans reserve on transaction abort")
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index 32e5defe4eff4..0d2212fa0ce85 100644
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -4106,9 +4106,7 @@ static void qgroup_convert_meta(struct btrfs_fs_info *fs_info, u64 ref_root,
 				int num_bytes)
 {
 	struct btrfs_qgroup *qgroup;
-	struct ulist_node *unode;
-	struct ulist_iterator uiter;
-	int ret = 0;
+	LIST_HEAD(qgroup_list);
 
 	if (num_bytes == 0)
 		return;
@@ -4119,31 +4117,21 @@ static void qgroup_convert_meta(struct btrfs_fs_info *fs_info, u64 ref_root,
 	qgroup = find_qgroup_rb(fs_info, ref_root);
 	if (!qgroup)
 		goto out;
-	ulist_reinit(fs_info->qgroup_ulist);
-	ret = ulist_add(fs_info->qgroup_ulist, qgroup->qgroupid,
-		       qgroup_to_aux(qgroup), GFP_ATOMIC);
-	if (ret < 0)
-		goto out;
-	ULIST_ITER_INIT(&uiter);
-	while ((unode = ulist_next(fs_info->qgroup_ulist, &uiter))) {
-		struct btrfs_qgroup *qg;
-		struct btrfs_qgroup_list *glist;
 
-		qg = unode_aux_to_qgroup(unode);
+	qgroup_iterator_add(&qgroup_list, qgroup);
+	list_for_each_entry(qgroup, &qgroup_list, iterator) {
+		struct btrfs_qgroup_list *glist;
 
-		qgroup_rsv_release(fs_info, qg, num_bytes,
+		qgroup_rsv_release(fs_info, qgroup, num_bytes,
 				BTRFS_QGROUP_RSV_META_PREALLOC);
-		qgroup_rsv_add(fs_info, qg, num_bytes,
+		qgroup_rsv_add(fs_info, qgroup, num_bytes,
 				BTRFS_QGROUP_RSV_META_PERTRANS);
-		list_for_each_entry(glist, &qg->groups, next_group) {
-			ret = ulist_add(fs_info->qgroup_ulist,
-					glist->group->qgroupid,
-					qgroup_to_aux(glist->group), GFP_ATOMIC);
-			if (ret < 0)
-				goto out;
-		}
+
+		list_for_each_entry(glist, &qgroup->groups, next_group)
+			qgroup_iterator_add(&qgroup_list, glist->group);
 	}
 out:
+	qgroup_iterator_clean(&qgroup_list);
 	spin_unlock(&fs_info->qgroup_lock);
 }