[PATCH] s390: fail-fast requests on quiesced devices

Using the fail-fast flag in i/o requests on a dasd disk which has been
quiesced leads to kernel panics.  Modify the request start function to only
work on requests in a valid state.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@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>
This commit is contained in:
Peter Oberparleiter 2006-04-10 22:53:47 -07:00 committed by Linus Torvalds
parent dafd87aaef
commit 25ee4cf831
1 changed files with 16 additions and 13 deletions

View File

@ -1257,25 +1257,28 @@ __dasd_start_head(struct dasd_device * device)
if (list_empty(&device->ccw_queue))
return;
cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, list);
/* check FAILFAST */
if (cqr->status != DASD_CQR_QUEUED)
return;
/* Non-temporary stop condition will trigger fail fast */
if (device->stopped & ~DASD_STOPPED_PENDING &&
test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
(!dasd_eer_enabled(device))) {
cqr->status = DASD_CQR_FAILED;
dasd_schedule_bh(device);
return;
}
if ((cqr->status == DASD_CQR_QUEUED) &&
(!device->stopped)) {
/* try to start the first I/O that can be started */
rc = device->discipline->start_IO(cqr);
if (rc == 0)
dasd_set_timer(device, cqr->expires);
else if (rc == -EACCES) {
dasd_schedule_bh(device);
} else
/* Hmpf, try again in 1/2 sec */
dasd_set_timer(device, 50);
}
/* Don't try to start requests if device is stopped */
if (device->stopped)
return;
rc = device->discipline->start_IO(cqr);
if (rc == 0)
dasd_set_timer(device, cqr->expires);
else if (rc == -EACCES) {
dasd_schedule_bh(device);
} else
/* Hmpf, try again in 1/2 sec */
dasd_set_timer(device, 50);
}
/*