staging: comedi: use refcount in comedi_driver_unregister()

Change `comedi_driver_unregister()` to call
`comedi_dev_get_from_minor()` instead of `comedi_dev_from_minor()` when
finding devices using the driver.  This increments the reference count
to prevent the device being removed while it is being checked to see if
it is attached to the driver.  Call `comedi_dev_put()` to decrement the
reference afterwards.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Ian Abbott 2013-11-08 15:03:35 +00:00 committed by Greg Kroah-Hartman
parent fc406986d4
commit a200fadca9

View file

@ -662,7 +662,7 @@ void comedi_driver_unregister(struct comedi_driver *driver)
/* check for devices using this driver */
for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) {
struct comedi_device *dev = comedi_dev_from_minor(i);
struct comedi_device *dev = comedi_dev_get_from_minor(i);
if (!dev)
continue;
@ -676,6 +676,7 @@ void comedi_driver_unregister(struct comedi_driver *driver)
comedi_device_detach(dev);
}
mutex_unlock(&dev->mutex);
comedi_dev_put(dev);
}
}
EXPORT_SYMBOL_GPL(comedi_driver_unregister);