s390/cio: fix unbind of io_subchannel_driver

If the io_subchannel_driver is unbound from a subchannel it bluntly kills
all I/O on the subchannel and sets the ccw_device state to not operable
before deregistering the ccw_device. However, for online devices we should
set the device offline (disband path groups etc.) which does not happen if
the device is in not oper state.

Simply deregister the ccw device - ccw_device_remove is smart enough to set
the device offline properly. If everything fails call io_subchannel_quiesce
afterwards as a safeguard.

Reported-by: Shalini Chellathurai Saroja <shalini@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Acked-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Sebastian Ott 2018-03-15 15:03:43 +01:00 committed by Martin Schwidefsky
parent 88bf319fc2
commit 135a8b4ce5
1 changed files with 8 additions and 8 deletions

View File

@ -1073,8 +1073,7 @@ static int io_subchannel_probe(struct subchannel *sch)
return 0;
}
static int
io_subchannel_remove (struct subchannel *sch)
static int io_subchannel_remove(struct subchannel *sch)
{
struct io_subchannel_private *io_priv = to_io_private(sch);
struct ccw_device *cdev;
@ -1082,14 +1081,12 @@ io_subchannel_remove (struct subchannel *sch)
cdev = sch_get_cdev(sch);
if (!cdev)
goto out_free;
io_subchannel_quiesce(sch);
/* Set ccw device to not operational and drop reference. */
spin_lock_irq(cdev->ccwlock);
ccw_device_unregister(cdev);
spin_lock_irq(sch->lock);
sch_set_cdev(sch, NULL);
set_io_private(sch, NULL);
cdev->private->state = DEV_STATE_NOT_OPER;
spin_unlock_irq(cdev->ccwlock);
ccw_device_unregister(cdev);
spin_unlock_irq(sch->lock);
out_free:
kfree(io_priv);
sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group);
@ -1721,6 +1718,7 @@ static int ccw_device_remove(struct device *dev)
{
struct ccw_device *cdev = to_ccwdev(dev);
struct ccw_driver *cdrv = cdev->drv;
struct subchannel *sch;
int ret;
if (cdrv->remove)
@ -1746,7 +1744,9 @@ static int ccw_device_remove(struct device *dev)
ccw_device_set_timeout(cdev, 0);
cdev->drv = NULL;
cdev->private->int_class = IRQIO_CIO;
sch = to_subchannel(cdev->dev.parent);
spin_unlock_irq(cdev->ccwlock);
io_subchannel_quiesce(sch);
__disable_cmf(cdev);
return 0;