s390/cio: Update purge function to unregister the unused subchannels

[ Upstream commit 9daa5a8795 ]

Starting with 'commit 2297791c92 ("s390/cio: dont unregister
subchannel from child-drivers")', cio no longer unregisters
subchannels when the attached device is invalid or unavailable.

As an unintended side-effect, the cio_ignore purge function no longer
removes subchannels for devices on the cio_ignore list if no CCW device
is attached. This situation occurs when a CCW device is non-operational
or unavailable

To ensure the same outcome of the purge function as when the
current cio_ignore list had been active during boot, update the purge
function to remove I/O subchannels without working CCW devices if the
associated device number is found on the cio_ignore list.

Fixes: 2297791c92 ("s390/cio: dont unregister subchannel from child-drivers")
Suggested-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Vineeth Vijayan
2025-10-01 15:38:17 +02:00
committed by Greg Kroah-Hartman
parent c772e7cc90
commit f224b06c72

View File

@@ -1318,23 +1318,34 @@ void ccw_device_schedule_recovery(void)
spin_unlock_irqrestore(&recovery_lock, flags); spin_unlock_irqrestore(&recovery_lock, flags);
} }
static int purge_fn(struct device *dev, void *data) static int purge_fn(struct subchannel *sch, void *data)
{ {
struct ccw_device *cdev = to_ccwdev(dev); struct ccw_device *cdev;
struct ccw_dev_id *id = &cdev->private->dev_id;
struct subchannel *sch = to_subchannel(cdev->dev.parent);
spin_lock_irq(cdev->ccwlock); spin_lock_irq(&sch->lock);
if (is_blacklisted(id->ssid, id->devno) && if (sch->st != SUBCHANNEL_TYPE_IO || !sch->schib.pmcw.dnv)
(cdev->private->state == DEV_STATE_OFFLINE) && goto unlock;
(atomic_cmpxchg(&cdev->private->onoff, 0, 1) == 0)) {
CIO_MSG_EVENT(3, "ccw: purging 0.%x.%04x\n", id->ssid, if (!is_blacklisted(sch->schid.ssid, sch->schib.pmcw.dev))
id->devno); goto unlock;
cdev = sch_get_cdev(sch);
if (cdev) {
if (cdev->private->state != DEV_STATE_OFFLINE)
goto unlock;
if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
goto unlock;
ccw_device_sched_todo(cdev, CDEV_TODO_UNREG); ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
css_sched_sch_todo(sch, SCH_TODO_UNREG);
atomic_set(&cdev->private->onoff, 0); atomic_set(&cdev->private->onoff, 0);
} }
spin_unlock_irq(cdev->ccwlock);
css_sched_sch_todo(sch, SCH_TODO_UNREG);
CIO_MSG_EVENT(3, "ccw: purging 0.%x.%04x%s\n", sch->schid.ssid,
sch->schib.pmcw.dev, cdev ? "" : " (no cdev)");
unlock:
spin_unlock_irq(&sch->lock);
/* Abort loop in case of pending signal. */ /* Abort loop in case of pending signal. */
if (signal_pending(current)) if (signal_pending(current))
return -EINTR; return -EINTR;
@@ -1350,7 +1361,7 @@ static int purge_fn(struct device *dev, void *data)
int ccw_purge_blacklisted(void) int ccw_purge_blacklisted(void)
{ {
CIO_MSG_EVENT(2, "ccw: purging blacklisted devices\n"); CIO_MSG_EVENT(2, "ccw: purging blacklisted devices\n");
bus_for_each_dev(&ccw_bus_type, NULL, NULL, purge_fn); for_each_subchannel_staged(purge_fn, NULL, NULL);
return 0; return 0;
} }