fs: dlm: bring back previous shutdown handling

This patch mostly reverts commit 4f567acb0b86 ("fs: dlm: remove socket
shutdown handling"). There can be situations where the dlm midcomms nodes
hash and lowcomms connection hash are not equal, but we need to guarantee
that the lowcomms are all closed on a last release of a dlm lockspace,
when a shutdown is invoked. This patch guarantees that we always close
all sockets managed by the lowcomms connection hash, and calls shutdown
for the last message sent. This ensures we don't cut the socket, which
could cause the peer to get a connection reset.

In future we should try to merge the midcomms/lowcomms hashes into one
hash and not handle both in separate hashes.

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

1 files changed, 7 insertions, 13 deletions

diff --git a/fs/dlm/midcomms.c b/fs/dlm/midcomms.c
index ecfb3beb0bb88..ecd81018d1cfb 100644
--- a/fs/dlm/midcomms.c
+++ b/fs/dlm/midcomms.c
@@ -1418,8 +1418,7 @@ static void midcomms_shutdown(struct midcomms_node *node)
 		break;
 	case DLM_CLOSED:
 		/* we have what we want */
-		spin_unlock(&node->state_lock);
-		return;
+		break;
 	default:
 		/* busy to enter DLM_FIN_WAIT1, wait until passive
 		 * done in shutdown_wait to enter DLM_CLOSED.
@@ -1436,17 +1435,12 @@ static void midcomms_shutdown(struct midcomms_node *node)
 				 node->state == DLM_CLOSED ||
 				 test_bit(DLM_NODE_FLAG_CLOSE, &node->flags),
 				 DLM_SHUTDOWN_TIMEOUT);
-	if (!ret || test_bit(DLM_NODE_FLAG_CLOSE, &node->flags)) {
+	if (!ret || test_bit(DLM_NODE_FLAG_CLOSE, &node->flags))
 		pr_debug("active shutdown timed out for node %d with state %s\n",
 			 node->nodeid, dlm_state_str(node->state));
-		midcomms_node_reset(node);
-		dlm_lowcomms_shutdown_node(node->nodeid, true);
-		return;
-	}
-
-	pr_debug("active shutdown done for node %d with state %s\n",
-		 node->nodeid, dlm_state_str(node->state));
-	dlm_lowcomms_shutdown_node(node->nodeid, false);
+	else
+		pr_debug("active shutdown done for node %d with state %s\n",
+			 node->nodeid, dlm_state_str(node->state));
 }
 
 void dlm_midcomms_shutdown(void)
@@ -1454,8 +1448,6 @@ void dlm_midcomms_shutdown(void)
 	struct midcomms_node *node;
 	int i, idx;
 
-	dlm_lowcomms_shutdown();
-
 	mutex_lock(&close_lock);
 	idx = srcu_read_lock(&nodes_srcu);
 	for (i = 0; i < CONN_HASH_SIZE; i++) {
@@ -1473,6 +1465,8 @@ void dlm_midcomms_shutdown(void)
 	}
 	srcu_read_unlock(&nodes_srcu, idx);
 	mutex_unlock(&close_lock);
+
+	dlm_lowcomms_shutdown();
 }
 
 int dlm_midcomms_close(int nodeid)