Upgrade to 4.4.50-rt62

[kvmfornfv.git] / kernel / drivers / s390 / scsi / zfcp_erp.c

diff --git a/kernel/drivers/s390/scsi/zfcp_erp.c b/kernel/drivers/s390/scsi/zfcp_erp.c
index 3fb4109..7ccfce5 100644 (file)
--- a/kernel/drivers/s390/scsi/zfcp_erp.c
+++ b/kernel/drivers/s390/scsi/zfcp_erp.c
@@ -3,7 +3,7 @@
  *
  * Error Recovery Procedures (ERP).
  *
- * Copyright IBM Corp. 2002, 2010
+ * Copyright IBM Corp. 2002, 2016
  */
 
 #define KMSG_COMPONENT "zfcp"
@@ -1204,6 +1204,62 @@ static void zfcp_erp_action_dequeue(struct zfcp_erp_action *erp_action)
        }
 }
 
+/**
+ * zfcp_erp_try_rport_unblock - unblock rport if no more/new recovery
+ * @port: zfcp_port whose fc_rport we should try to unblock
+ */
+static void zfcp_erp_try_rport_unblock(struct zfcp_port *port)
+{
+       unsigned long flags;
+       struct zfcp_adapter *adapter = port->adapter;
+       int port_status;
+       struct Scsi_Host *shost = adapter->scsi_host;
+       struct scsi_device *sdev;
+
+       write_lock_irqsave(&adapter->erp_lock, flags);
+       port_status = atomic_read(&port->status);
+       if ((port_status & ZFCP_STATUS_COMMON_UNBLOCKED)    == 0 ||
+           (port_status & (ZFCP_STATUS_COMMON_ERP_INUSE |
+                           ZFCP_STATUS_COMMON_ERP_FAILED)) != 0) {
+               /* new ERP of severity >= port triggered elsewhere meanwhile or
+                * local link down (adapter erp_failed but not clear unblock)
+                */
+               zfcp_dbf_rec_run_lvl(4, "ertru_p", &port->erp_action);
+               write_unlock_irqrestore(&adapter->erp_lock, flags);
+               return;
+       }
+       spin_lock(shost->host_lock);
+       __shost_for_each_device(sdev, shost) {
+               struct zfcp_scsi_dev *zsdev = sdev_to_zfcp(sdev);
+               int lun_status;
+
+               if (zsdev->port != port)
+                       continue;
+               /* LUN under port of interest */
+               lun_status = atomic_read(&zsdev->status);
+               if ((lun_status & ZFCP_STATUS_COMMON_ERP_FAILED) != 0)
+                       continue; /* unblock rport despite failed LUNs */
+               /* LUN recovery not given up yet [maybe follow-up pending] */
+               if ((lun_status & ZFCP_STATUS_COMMON_UNBLOCKED) == 0 ||
+                   (lun_status & ZFCP_STATUS_COMMON_ERP_INUSE) != 0) {
+                       /* LUN blocked:
+                        * not yet unblocked [LUN recovery pending]
+                        * or meanwhile blocked [new LUN recovery triggered]
+                        */
+                       zfcp_dbf_rec_run_lvl(4, "ertru_l", &zsdev->erp_action);
+                       spin_unlock(shost->host_lock);
+                       write_unlock_irqrestore(&adapter->erp_lock, flags);
+                       return;
+               }
+       }
+       /* now port has no child or all children have completed recovery,
+        * and no ERP of severity >= port was meanwhile triggered elsewhere
+        */
+       zfcp_scsi_schedule_rport_register(port);
+       spin_unlock(shost->host_lock);
+       write_unlock_irqrestore(&adapter->erp_lock, flags);
+}
+
 static void zfcp_erp_action_cleanup(struct zfcp_erp_action *act, int result)
 {
        struct zfcp_adapter *adapter = act->adapter;
@@ -1214,11 +1270,18 @@ static void zfcp_erp_action_cleanup(struct zfcp_erp_action *act, int result)
        case ZFCP_ERP_ACTION_REOPEN_LUN:
                if (!(act->status & ZFCP_STATUS_ERP_NO_REF))
                        scsi_device_put(sdev);
+               zfcp_erp_try_rport_unblock(port);
                break;
 
        case ZFCP_ERP_ACTION_REOPEN_PORT:
-               if (result == ZFCP_ERP_SUCCEEDED)
-                       zfcp_scsi_schedule_rport_register(port);
+               /* This switch case might also happen after a forced reopen
+                * was successfully done and thus overwritten with a new
+                * non-forced reopen at `ersfs_2'. In this case, we must not
+                * do the clean-up of the non-forced version.
+                */
+               if (act->step != ZFCP_ERP_STEP_UNINITIALIZED)
+                       if (result == ZFCP_ERP_SUCCEEDED)
+                               zfcp_erp_try_rport_unblock(port);
                /* fall through */
        case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
                put_device(&port->dev);