diff options
| author | Horst Hummel <horst.hummel@de.ibm.com> | 2006-01-06 00:19:15 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-01-06 08:33:50 -0800 |
| commit | 1c01b8a5963aec60488c1c97d67cffd8b5275e3f (patch) | |
| tree | 48eb6c300541d77ff2cc5d8949ce5788fab1d82f /drivers/s390/block/dasd.c | |
| parent | 9a7af289660dc749d7c58234191601046a9bf488 (diff) | |
[PATCH] s390: dasd failfast support
To properly support multipath-failover handling, the linux block layer has
introduced a special request flag, 'REQ_FAILFAST'. This flag is now used to
return requests immediately in case the device is not operational.
Signed-off-by: Horst Hummel <horst.hummel@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>
Diffstat (limited to 'drivers/s390/block/dasd.c')
| -rw-r--r-- | drivers/s390/block/dasd.c | 28 |
1 files changed, 20 insertions, 8 deletions
diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c index 62787393a209..1141a5963b67 100644 --- a/drivers/s390/block/dasd.c +++ b/drivers/s390/block/dasd.c @@ -7,7 +7,7 @@ * Bugreports.to..: <Linux390@de.ibm.com> * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999-2001 * - * $Revision: 1.169 $ + * $Revision: 1.172 $ */ #include <linux/config.h> @@ -1224,6 +1224,12 @@ __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 (device->stopped & ~DASD_STOPPED_PENDING && + test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags)) { + cqr->status = DASD_CQR_FAILED; + dasd_schedule_bh(device); + } if ((cqr->status == DASD_CQR_QUEUED) && (!device->stopped)) { /* try to start the first I/O that can be started */ @@ -1750,8 +1756,10 @@ dasd_exit(void) * SECTION: common functions for ccw_driver use */ -/* initial attempt at a probe function. this can be simplified once - * the other detection code is gone */ +/* + * Initial attempt at a probe function. this can be simplified once + * the other detection code is gone. + */ int dasd_generic_probe (struct ccw_device *cdev, struct dasd_discipline *discipline) @@ -1770,8 +1778,10 @@ dasd_generic_probe (struct ccw_device *cdev, return ret; } -/* this will one day be called from a global not_oper handler. - * It is also used by driver_unregister during module unload */ +/* + * This will one day be called from a global not_oper handler. + * It is also used by driver_unregister during module unload. + */ void dasd_generic_remove (struct ccw_device *cdev) { @@ -1798,9 +1808,11 @@ dasd_generic_remove (struct ccw_device *cdev) dasd_delete_device(device); } -/* activate a device. This is called from dasd_{eckd,fba}_probe() when either +/* + * Activate a device. This is called from dasd_{eckd,fba}_probe() when either * the device is detected for the first time and is supposed to be used - * or the user has started activation through sysfs */ + * or the user has started activation through sysfs. + */ int dasd_generic_set_online (struct ccw_device *cdev, struct dasd_discipline *discipline) @@ -1917,7 +1929,6 @@ dasd_generic_notify(struct ccw_device *cdev, int event) if (cqr->status == DASD_CQR_IN_IO) cqr->status = DASD_CQR_FAILED; device->stopped |= DASD_STOPPED_DC_EIO; - dasd_schedule_bh(device); } else { list_for_each_entry(cqr, &device->ccw_queue, list) if (cqr->status == DASD_CQR_IN_IO) { @@ -1927,6 +1938,7 @@ dasd_generic_notify(struct ccw_device *cdev, int event) device->stopped |= DASD_STOPPED_DC_WAIT; dasd_set_timer(device, 0); } + dasd_schedule_bh(device); ret = 1; break; case CIO_OPER: |