s390/cio: recover from bad paths
In some situations we don't receive notification from firmware that
a previously unusable channelpath is usable again.
Schedule recovery for devices that return from path verification
without using all potentially usable paths. The recovery thread will
periodically trigger a path verification on the affected devices.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Suggested-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/cio/device.c b/drivers/s390/cio/device.c
index 489b583..e5c32f4 100644
--- a/drivers/s390/cio/device.c
+++ b/drivers/s390/cio/device.c
@@ -1225,10 +1225,16 @@ static int device_is_disconnected(struct ccw_device *cdev)
static int recovery_check(struct device *dev, void *data)
{
struct ccw_device *cdev = to_ccwdev(dev);
+ struct subchannel *sch;
int *redo = data;
spin_lock_irq(cdev->ccwlock);
switch (cdev->private->state) {
+ case DEV_STATE_ONLINE:
+ sch = to_subchannel(cdev->dev.parent);
+ if ((sch->schib.pmcw.pam & sch->opm) == sch->vpm)
+ break;
+ /* fall through */
case DEV_STATE_DISCONNECTED:
CIO_MSG_EVENT(3, "recovery: trigger 0.%x.%04x\n",
cdev->private->dev_id.ssid,
@@ -1260,7 +1266,7 @@ static void recovery_work_func(struct work_struct *unused)
}
spin_unlock_irq(&recovery_lock);
} else
- CIO_MSG_EVENT(4, "recovery: end\n");
+ CIO_MSG_EVENT(3, "recovery: end\n");
}
static DECLARE_WORK(recovery_work, recovery_work_func);
@@ -1274,11 +1280,11 @@ static void recovery_func(unsigned long data)
schedule_work(&recovery_work);
}
-static void ccw_device_schedule_recovery(void)
+void ccw_device_schedule_recovery(void)
{
unsigned long flags;
- CIO_MSG_EVENT(4, "recovery: schedule\n");
+ CIO_MSG_EVENT(3, "recovery: schedule\n");
spin_lock_irqsave(&recovery_lock, flags);
if (!timer_pending(&recovery_timer) || (recovery_phase != 0)) {
recovery_phase = 0;