[S390] cio chpid offline.

After setting a path to a dasd offline at the SE, I/O hangs on that
dasd for 5 minutes, then continues.
I/O for which an interrupt will not be reported after the channel
path has been disabled was not terminated by the common I/O layer,
causing the dasd MIH to hit after 5 minutes.

Be more aggressive in terminating I/O after setting a channel path
offline. Also make sure to generate a fake irb if the device
driver issues an I/O request after being notified of the killed
I/O and clear residual information from the irb before trying to
start the delayed verification.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/cio/device_fsm.c b/drivers/s390/cio/device_fsm.c
index 49ec562..5ec8ef1 100644
--- a/drivers/s390/cio/device_fsm.c
+++ b/drivers/s390/cio/device_fsm.c
@@ -861,6 +861,8 @@
 	irb = (struct irb *) __LC_IRB;
 	/* Accumulate status. We don't do basic sense. */
 	ccw_device_accumulate_irb(cdev, irb);
+	/* Remember to clear irb to avoid residuals. */
+	memset(&cdev->private->irb, 0, sizeof(struct irb));
 	/* Try to start delayed device verification. */
 	ccw_device_online_verify(cdev, 0);
 	/* Note: Don't call handler for cio initiated clear! */