[PATCH] s390: fix endless retry loop in tape driver

If a tape device is assigned to another host, the interrupt for the assign
operation comes back with deferred condition code 1.  Under some conditions
this can lead to an endless loop of retries.  Check if the current request is
still in IO in deferred condition code handling and prevent retries when the
request has already been cancelled.

Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
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>