Btrfs: add ioctl to wait for qgroup rescan completion
btrfs_qgroup_wait_for_completion waits until the currently running qgroup
operation completes. It returns immediately when no rescan process is in
progress. This is useful to automate things around the rescan process (e.g.
testing).
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index 7f38cce..d059d86 100644
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -2070,6 +2070,8 @@
} else {
pr_err("btrfs: qgroup scan failed with %d\n", err);
}
+
+ complete_all(&fs_info->qgroup_rescan_completion);
}
static void
@@ -2110,6 +2112,7 @@
fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_RESCAN;
memset(&fs_info->qgroup_rescan_progress, 0,
sizeof(fs_info->qgroup_rescan_progress));
+ init_completion(&fs_info->qgroup_rescan_completion);
/* clear all current qgroup tracking information */
for (n = rb_first(&fs_info->qgroup_tree); n; n = rb_next(n)) {
@@ -2126,3 +2129,21 @@
return 0;
}
+
+int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info)
+{
+ int running;
+ int ret = 0;
+
+ mutex_lock(&fs_info->qgroup_rescan_lock);
+ spin_lock(&fs_info->qgroup_lock);
+ running = fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN;
+ spin_unlock(&fs_info->qgroup_lock);
+ mutex_unlock(&fs_info->qgroup_rescan_lock);
+
+ if (running)
+ ret = wait_for_completion_interruptible(
+ &fs_info->qgroup_rescan_completion);
+
+ return ret;
+}