[S390] dasd: Prevent deadlock during suspend/resume.

The freeze callback may set a stop bit so that a worker thread could
not start I/O. The discipline specific freeze function waits for the
worker to be completed.
Set the stop_bit after the discipline specific freeze function has
returned and no worker is running.

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Stefan Haberland 2011-01-05 12:48:05 +01:00 committed by Martin Schwidefsky
parent 5a27e60dec
commit 6f272b9cec

View file

@ -2769,6 +2769,10 @@ int dasd_generic_pm_freeze(struct ccw_device *cdev)
if (IS_ERR(device))
return PTR_ERR(device);
if (device->discipline->freeze)
rc = device->discipline->freeze(device);
/* disallow new I/O */
dasd_device_set_stop_bits(device, DASD_STOPPED_PM);
/* clear active requests */
@ -2805,9 +2809,6 @@ int dasd_generic_pm_freeze(struct ccw_device *cdev)
list_splice_tail(&freeze_queue, &device->ccw_queue);
spin_unlock_irq(get_ccwdev_lock(cdev));
if (device->discipline->freeze)
rc = device->discipline->freeze(device);
dasd_put_device(device);
return rc;
}