Common i/o layer changes:
 - Update scsw information before checking activity control bits in
   the offline processing.
 - Clear irb structure after cio initiated I/O completed.
 - Modify cdev private structure only while holding the lock.
 - Update scsw information before checking whether we can start path
   verification.
 - Only generate a notoper event if the device is not already in the
   not operation state, otherwise we end up with two unregister calls.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>