[S390] dasd: fix unconditional reserve handling.

[S390] dasd: fix unconditional reserve handling.

[Martin Schwidefsky]

From: Horst Hummel <horst.hummel@de.ibm.com>

[S390] dasd: fix unconditional reserve handling.

The reserve/release IOCTLs sometimes do not work. If second system
does a 'steal lock' the pending unit check (Format 3 Msg F) is
delivered. Since ERP is disabled for reserve/release, the IOCTL call
fails. We have to allow basic ERP (retries) for reserve/release IOCTLs.

Signed-off-by: Horst Hummel <horst.hummel@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---

 drivers/s390/block/dasd.c      |    6 +++---
 drivers/s390/block/dasd_eckd.c |    6 +++---
 2 files changed, 6 insertions(+), 6 deletions(-)

diff -urpN linux-2.6/drivers/s390/block/dasd.c linux-2.6-patched/drivers/s390/block/dasd.c
--- linux-2.6/drivers/s390/block/dasd.c	2007-01-26 17:27:47.000000000 +0100
+++ linux-2.6-patched/drivers/s390/block/dasd.c	2007-01-26 17:28:03.000000000 +0100
@@ -1022,8 +1022,6 @@ dasd_int_handler(struct ccw_device *cdev
 		 irb->scsw.cstat == 0 &&
 		 !irb->esw.esw0.erw.cons)
 		era = dasd_era_none;
-	else if (!test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags))
- 	        era = dasd_era_fatal; /* don't recover this request */
 	else if (irb->esw.esw0.erw.cons)
 		era = device->discipline->examine_error(cqr, irb);
 	else
@@ -1127,7 +1125,9 @@ restart:
 				cqr->status = DASD_CQR_FAILED;
 				cqr->stopclk = get_clock();
 			} else {
-				if (cqr->irb.esw.esw0.erw.cons) {
+				if (cqr->irb.esw.esw0.erw.cons &&
+				    test_bit(DASD_CQR_FLAGS_USE_ERP,
+					     &cqr->flags)) {
 					erp_fn = device->discipline->
 						erp_action(cqr);
 					erp_fn(cqr);
diff -urpN linux-2.6/drivers/s390/block/dasd_eckd.c linux-2.6-patched/drivers/s390/block/dasd_eckd.c
--- linux-2.6/drivers/s390/block/dasd_eckd.c	2007-01-26 17:27:47.000000000 +0100
+++ linux-2.6-patched/drivers/s390/block/dasd_eckd.c	2007-01-26 17:28:03.000000000 +0100
@@ -1380,7 +1380,7 @@ dasd_eckd_release(struct dasd_device *de
 	cqr->device = device;
 	clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
 	set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
-	cqr->retries = 0;
+	cqr->retries = 2;	/* set retry counter to enable basic ERP */
 	cqr->expires = 2 * HZ;
 	cqr->buildclk = get_clock();
 	cqr->status = DASD_CQR_FILLED;
@@ -1420,7 +1420,7 @@ dasd_eckd_reserve(struct dasd_device *de
 	cqr->device = device;
 	clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
 	set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
-	cqr->retries = 0;
+	cqr->retries = 2;	/* set retry counter to enable basic ERP */
 	cqr->expires = 2 * HZ;
 	cqr->buildclk = get_clock();
 	cqr->status = DASD_CQR_FILLED;
@@ -1459,7 +1459,7 @@ dasd_eckd_steal_lock(struct dasd_device 
 	cqr->device = device;
 	clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
 	set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
-	cqr->retries = 0;
+	cqr->retries = 2;	/* set retry counter to enable basic ERP */
 	cqr->expires = 2 * HZ;
 	cqr->buildclk = get_clock();
 	cqr->status = DASD_CQR_FILLED;