From 7fbadd86b23c911d229239fb626ade3a6dc257d5 Mon Sep 17 00:00:00 2001 From: Arne Jansen Date: Thu, 17 Jan 2013 01:22:09 -0700 Subject: [PATCH] Btrfs: prevent qgroup destroy when there are still relations Currently you can just destroy a qgroup even though it is in use by other qgroups or has qgroups assigned to it. This patch prevents destruction of qgroups unless they are completely unused. Otherwise destroy will return EBUSY. Reported-by: Eric Hopper Signed-off-by: Arne Jansen Signed-off-by: Chris Mason --- fs/btrfs/qgroup.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c index 28f2b39f6a25d..a5c8562343232 100644 --- a/fs/btrfs/qgroup.c +++ b/fs/btrfs/qgroup.c @@ -963,17 +963,28 @@ int btrfs_remove_qgroup(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info, u64 qgroupid) { struct btrfs_root *quota_root; + struct btrfs_qgroup *qgroup; int ret = 0; quota_root = fs_info->quota_root; if (!quota_root) return -EINVAL; + /* check if there are no relations to this qgroup */ + spin_lock(&fs_info->qgroup_lock); + qgroup = find_qgroup_rb(fs_info, qgroupid); + if (qgroup) { + if (!list_empty(&qgroup->groups) || !list_empty(&qgroup->members)) { + spin_unlock(&fs_info->qgroup_lock); + return -EBUSY; + } + } + spin_unlock(&fs_info->qgroup_lock); + ret = del_qgroup_item(trans, quota_root, qgroupid); spin_lock(&fs_info->qgroup_lock); del_qgroup_rb(quota_root->fs_info, qgroupid); - spin_unlock(&fs_info->qgroup_lock); return ret; -- 2.39.5