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[S390] pm: vmur driver power management callbacks 

Signed-off-by: Frank Munzert <munzert@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Frank Munzert 2009-06-16 10:30:37 +02:00 committed by Martin Schwidefsky
parent 524dbcdad7
commit b241f7bcc6
1 changed files with 25 additions and 1 deletions
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26
drivers/s390/char/vmur.c
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@ -2,7 +2,7 @@
* Linux driver for System z and s390 unit record devices
* (z/VM virtual punch, reader, printer)
*
* Copyright IBM Corp. 2001, 2007
* Copyright IBM Corp. 2001, 2009
* Authors: Malcolm Beattie <beattiem@uk.ibm.com>
* Michael Holzheu <holzheu@de.ibm.com>
* Frank Munzert <munzert@de.ibm.com>
@ -60,6 +60,7 @@ static int ur_probe(struct ccw_device *cdev);
static void ur_remove(struct ccw_device *cdev);
static int ur_set_online(struct ccw_device *cdev);
static int ur_set_offline(struct ccw_device *cdev);
static int ur_pm_suspend(struct ccw_device *cdev);
static struct ccw_driver ur_driver = {
.name = "vmur",
@ -69,6 +70,7 @@ static struct ccw_driver ur_driver = {
.remove = ur_remove,
.set_online = ur_set_online,
.set_offline = ur_set_offline,
.freeze = ur_pm_suspend,
};
static DEFINE_MUTEX(vmur_mutex);
@ -157,6 +159,28 @@ static void urdev_put(struct urdev *urd)
urdev_free(urd);
}
/*
* State and contents of ur devices can be changed by class D users issuing
* CP commands such as PURGE or TRANSFER, while the Linux guest is suspended.
* Also the Linux guest might be logged off, which causes all active spool
* files to be closed.
* So we cannot guarantee that spool files are still the same when the Linux
* guest is resumed. In order to avoid unpredictable results at resume time
* we simply refuse to suspend if a ur device node is open.
*/
static int ur_pm_suspend(struct ccw_device *cdev)
{
struct urdev *urd = cdev->dev.driver_data;
TRACE("ur_pm_suspend: cdev=%p\n", cdev);
if (urd->open_flag) {
pr_err("Unit record device %s is busy, %s refusing to "
"suspend.\n", dev_name(&cdev->dev), ur_banner);
return -EBUSY;
}
return 0;
}
/*
* Low-level functions to do I/O to a ur device.
* alloc_chan_prog