scsi: qla2xxx: edif: Reduce connection thrash

On ipsec start by remote port, target port may use RSCN to trigger
initiator to relogin. If driver is already in the process of a relogin,
then ignore the RSCN and allow the current relogin to continue. This
reduces thrashing of the connection.

Link: https://lore.kernel.org/r/20211026115412.27691-10-njavali@marvell.comReviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Quinn Tran <qutran@marvell.com>
Signed-off-by: Nilesh Javali <njavali@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/qla2xxx/qla_attr.c

@@ -2762,7 +2762,12 @@ qla2x00_terminate_rport_io(struct fc_rport *rport)
 			if (fcport->loop_id != FC_NO_LOOP_ID)
 				fcport->logout_on_delete = 1;
 
-			qlt_schedule_sess_for_deletion(fcport);
+			if (!EDIF_NEGOTIATION_PENDING(fcport)) {
+				ql_dbg(ql_dbg_disc, fcport->vha, 0x911e,
+				       "%s %d schedule session deletion\n", __func__,
+				       __LINE__);
+				qlt_schedule_sess_for_deletion(fcport);
+			}
 		} else {
 			qla2x00_port_logout(fcport->vha, fcport);
 		}

drivers/scsi/qla2xxx/qla_edif.h

@@ -132,4 +132,8 @@ struct enode {
 	 _s->disc_state == DSC_DELETED || \
 	 !_s->edif.app_sess_online))
 
+#define EDIF_NEGOTIATION_PENDING(_fcport) \
+	((_fcport->vha.e_dbell.db_flags & EDB_ACTIVE) && \
+	 (_fcport->disc_state == DSC_LOGIN_AUTH_PEND))
+
 #endif	/* __QLA_EDIF_H */

drivers/scsi/qla2xxx/qla_init.c

@@ -1793,8 +1793,28 @@ void qla2x00_handle_rscn(scsi_qla_host_t *vha, struct event_arg *ea)
 					fcport->d_id.b24, fcport->port_name);
 				return;
 			}
-			fcport->scan_needed = 1;
-			fcport->rscn_gen++;
+
+			if (vha->hw->flags.edif_enabled && vha->e_dbell.db_flags & EDB_ACTIVE) {
+				/*
+				 * On ipsec start by remote port, Target port
+				 * may use RSCN to trigger initiator to
+				 * relogin. If driver is already in the
+				 * process of a relogin, then ignore the RSCN
+				 * and allow the current relogin to continue.
+				 * This reduces thrashing of the connection.
+				 */
+				if (atomic_read(&fcport->state) == FCS_ONLINE) {
+					/*
+					 * If state = online, then set scan_needed=1 to do relogin.
+					 * Otherwise we're already in the middle of a relogin
+					 */
+					fcport->scan_needed = 1;
+					fcport->rscn_gen++;
+				}
+			} else {
+				fcport->scan_needed = 1;
+				fcport->rscn_gen++;
+			}
 		}
 		break;
 	case RSCN_AREA_ADDR: