dlm: check required context while close

This patch adds a WARN_ON() check to validate the right context while
dlm_midcomms_close() is called. Even before commit 489d8e559c65
("fs: dlm: add reliable connection if reconnect") in this context
dlm_lowcomms_close() flushes all ongoing transmission triggered by dlm
application stack. If we do that, it's required that no new message will
be triggered by the dlm application stack. The function
dlm_midcomms_close() is not called often so we can check if all
lockspaces are in such context.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/fs/dlm/lockspace.c b/fs/dlm/lockspace.c
index 0d3833a124a3..19ed41a5da93 100644
--- a/fs/dlm/lockspace.c
+++ b/fs/dlm/lockspace.c
@@ -922,3 +922,15 @@ void dlm_stop_lockspaces(void)
 		log_print("dlm user daemon left %d lockspaces", count);
 }
 
+void dlm_stop_lockspaces_check(void)
+{
+	struct dlm_ls *ls;
+
+	spin_lock(&lslist_lock);
+	list_for_each_entry(ls, &lslist, ls_list) {
+		if (WARN_ON(!rwsem_is_locked(&ls->ls_in_recovery) ||
+			    !dlm_locking_stopped(ls)))
+			break;
+	}
+	spin_unlock(&lslist_lock);
+}