Fix a race condition in the I/O termination logic.  The race can cause I/O to
a dasd device to fail with no retry left after turning one channel path to the
device off and on multiple times.
Signed-off-by: NPeter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>