ceph: connect to export targets if mds is laggy

If an MDS we are talking to may have failed, we need to open sessions to
its potential export targets to ensure that any in-progress migration that
may have involved some of our caps is properly handled.

Signed-off-by: Sage Weil <sage@newdream.net>

diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 21c344ba2449cdb636fbab70c2c1fbe1502fdc15..29faa3b6f1af07a1157e0f699196c4f81bd5d727 100644 (file)
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -2445,6 +2445,21 @@ static void check_new_map(struct ceph_mds_client *mdsc,
                        wake_up_session_caps(s, 1);
                }
        }
+
+       for (i = 0; i < newmap->m_max_mds && i < mdsc->max_sessions; i++) {
+               s = mdsc->sessions[i];
+               if (!s)
+                       continue;
+               if (!ceph_mdsmap_is_laggy(newmap, i))
+                       continue;
+               if (s->s_state == CEPH_MDS_SESSION_OPEN ||
+                   s->s_state == CEPH_MDS_SESSION_HUNG ||
+                   s->s_state == CEPH_MDS_SESSION_CLOSING) {
+                       dout(" connecting to export targets of laggy mds%d\n",
+                            i);
+                       __open_export_target_sessions(mdsc, s);
+               }
+       }
 }