s390/cio: reactivate cmf after hibernate

During resume from hibernate we already reenable measurement block
updates on a per device basis. In addition to that we also need to
activate channel measurement globally using the set channel monitor
instruction.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

drivers/s390/cio/cmf.c

@@ -1312,6 +1312,19 @@ int cmf_reenable(struct ccw_device *cdev)
 	return cmbops->set(cdev, 2);
 }
 
+/**
+ * cmf_reactivate() - reactivate measurement block updates
+ *
+ * Use this during resume from hibernate.
+ */
+void cmf_reactivate(void)
+{
+	spin_lock(&cmb_area.lock);
+	if (!list_empty(&cmb_area.list))
+		cmf_activate(cmb_area.mem, 1);
+	spin_unlock(&cmb_area.lock);
+}
+
 static int __init init_cmbe(void)
 {
 	cmbe_cache = kmem_cache_create("cmbe_cache", sizeof(struct cmbe),

drivers/s390/cio/css.c

@@ -1089,6 +1089,7 @@ void channel_subsystem_reinit(void)
 		if (chp)
 			chp_update_desc(chp);
 	}
+	cmf_reactivate();
 }
 
 #ifdef CONFIG_PROC_FS

drivers/s390/cio/device.h

@@ -145,6 +145,7 @@ void ccw_device_set_timeout(struct ccw_device *, int);
 void retry_set_schib(struct ccw_device *cdev);
 void cmf_retry_copy_block(struct ccw_device *);
 int cmf_reenable(struct ccw_device *);
+void cmf_reactivate(void);
 int ccw_set_cmf(struct ccw_device *cdev, int enable);
 extern struct device_attribute dev_attr_cmb_enable;
 #endif