From 1c01b8a5963aec60488c1c97d67cffd8b5275e3f Mon Sep 17 00:00:00 2001 From: Horst Hummel Date: Fri, 6 Jan 2006 00:19:15 -0800 Subject: [PATCH] [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 Signed-off-by: Martin Schwidefsky Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/s390/block/dasd.c | 28 ++++++++++++++++++++-------- drivers/s390/block/dasd_diag.c | 4 +++- drivers/s390/block/dasd_eckd.c | 7 ++++++- drivers/s390/block/dasd_fba.c | 4 +++- drivers/s390/block/dasd_int.h | 3 ++- 5 files changed, 34 insertions(+), 12 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..: * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999-2001 * - * $Revision: 1.169 $ + * $Revision: 1.172 $ */ #include @@ -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: diff --git a/drivers/s390/block/dasd_diag.c b/drivers/s390/block/dasd_diag.c index 16c4b7d94bd7..a33d4064b537 100644 --- a/drivers/s390/block/dasd_diag.c +++ b/drivers/s390/block/dasd_diag.c @@ -6,7 +6,7 @@ * Bugreports.to..: * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999,2000 * - * $Revision: 1.52 $ + * $Revision: 1.53 $ */ #include @@ -549,6 +549,8 @@ dasd_diag_build_cp(struct dasd_device * device, struct request *req) } cqr->retries = DIAG_MAX_RETRIES; cqr->buildclk = get_clock(); + if (req->flags & REQ_FAILFAST) + set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags); cqr->device = device; cqr->expires = DIAG_TIMEOUT; cqr->status = DASD_CQR_FILLED; diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c index 811060e10c00..efc4cf62496e 100644 --- a/drivers/s390/block/dasd_eckd.c +++ b/drivers/s390/block/dasd_eckd.c @@ -7,7 +7,7 @@ * Bugreports.to..: * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999,2000 * - * $Revision: 1.71 $ + * $Revision: 1.74 $ */ #include @@ -1136,6 +1136,8 @@ dasd_eckd_build_cp(struct dasd_device * device, struct request *req) recid++; } } + if (req->flags & REQ_FAILFAST) + set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags); cqr->device = device; cqr->expires = 5 * 60 * HZ; /* 5 minutes */ cqr->lpm = private->path_data.ppm; @@ -1252,6 +1254,7 @@ dasd_eckd_release(struct block_device *bdev, int no, long args) cqr->cpaddr->cda = (__u32)(addr_t) cqr->data; cqr->device = device; clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags); + set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags); cqr->retries = 0; cqr->expires = 2 * HZ; cqr->buildclk = get_clock(); @@ -1296,6 +1299,7 @@ dasd_eckd_reserve(struct block_device *bdev, int no, long args) cqr->cpaddr->cda = (__u32)(addr_t) cqr->data; cqr->device = device; clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags); + set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags); cqr->retries = 0; cqr->expires = 2 * HZ; cqr->buildclk = get_clock(); @@ -1339,6 +1343,7 @@ dasd_eckd_steal_lock(struct block_device *bdev, int no, long args) cqr->cpaddr->cda = (__u32)(addr_t) cqr->data; cqr->device = device; clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags); + set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags); cqr->retries = 0; cqr->expires = 2 * HZ; cqr->buildclk = get_clock(); diff --git a/drivers/s390/block/dasd_fba.c b/drivers/s390/block/dasd_fba.c index 28cb4613b7f5..9bac8d87a9cc 100644 --- a/drivers/s390/block/dasd_fba.c +++ b/drivers/s390/block/dasd_fba.c @@ -4,7 +4,7 @@ * Bugreports.to..: * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999,2000 * - * $Revision: 1.40 $ + * $Revision: 1.41 $ */ #include @@ -352,6 +352,8 @@ dasd_fba_build_cp(struct dasd_device * device, struct request *req) recid++; } } + if (req->flags & REQ_FAILFAST) + set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags); cqr->device = device; cqr->expires = 5 * 60 * HZ; /* 5 minutes */ cqr->retries = 32; diff --git a/drivers/s390/block/dasd_int.h b/drivers/s390/block/dasd_int.h index 9fab04f3056d..2fb05c4a528c 100644 --- a/drivers/s390/block/dasd_int.h +++ b/drivers/s390/block/dasd_int.h @@ -6,7 +6,7 @@ * Bugreports.to..: * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999,2000 * - * $Revision: 1.65 $ + * $Revision: 1.68 $ */ #ifndef DASD_INT_H @@ -208,6 +208,7 @@ struct dasd_ccw_req { /* per dasd_ccw_req flags */ #define DASD_CQR_FLAGS_USE_ERP 0 /* use ERP for this request */ +#define DASD_CQR_FLAGS_FAILFAST 1 /* FAILFAST */ /* Signature for error recovery functions. */ typedef struct dasd_ccw_req *(*dasd_erp_fn_t) (struct dasd_ccw_req *);