This is a note to let you know that I've just added the patch titled
btrfs: forbid deleting live subvol qgroup
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-forbid-deleting-live-subvol-qgroup.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.
>From a8df35619948bd8363d330c20a90c9a7fbff28c0 Mon Sep 17 00:00:00 2001
From: Boris Burkov <boris@xxxxxx>
Date: Wed, 10 Jan 2024 17:30:00 -0800
Subject: btrfs: forbid deleting live subvol qgroup
From: Boris Burkov <boris@xxxxxx>
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@xxxxxxxxxxxxxxx # 5.4+
Reviewed-by: Qu Wenruo <wqu@xxxxxxxx>
Signed-off-by: Boris Burkov <boris@xxxxxx>
Reviewed-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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;
Patches currently in stable-queue which might be from boris@xxxxxx are
queue-6.6/btrfs-forbid-creating-subvol-qgroups.patch
queue-6.6/btrfs-forbid-deleting-live-subvol-qgroup.patch
queue-6.6/btrfs-do-not-delete-unused-block-group-if-it-may-be-used-soon.patch
queue-6.6/btrfs-add-and-use-helper-to-check-if-block-group-is-used.patch
