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authorStefan Weinhuber <wein@de.ibm.com>2011-01-05 12:48:04 +0100
committerMartin Schwidefsky <sky@mschwide.boeblingen.de.ibm.com>2011-01-05 12:47:30 +0100
commit5a27e60dec59a95bd7f8ae9a19ae2ede4f76395b (patch)
tree20595cba0caebf7a8a5f0afac9785c7d717f3e8c
parenta4d26c6aeceea330ee5e0fb6b017d57e3b252d29 (diff)
[S390] dasd: Improve handling of stolen DASD reservation
If a DASD device has been reserved by a Linux system, and later this reservation is ‘stolen’ by a second system by means of an unconditional reserve, then the first system receives a notification about this fact. With this patch such an event can be either ignored, as before, or it can be used to let the device fail all I/O request, so that the device will not block anymore. Signed-off-by: Stefan Weinhuber <wein@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
-rw-r--r--arch/s390/include/asm/dasd.h1
-rw-r--r--drivers/s390/block/dasd.c75
-rw-r--r--drivers/s390/block/dasd_devmap.c99
-rw-r--r--drivers/s390/block/dasd_eckd.c51
-rw-r--r--drivers/s390/block/dasd_eer.c1
-rw-r--r--drivers/s390/block/dasd_fba.c18
-rw-r--r--drivers/s390/block/dasd_int.h13
7 files changed, 189 insertions, 69 deletions
diff --git a/arch/s390/include/asm/dasd.h b/arch/s390/include/asm/dasd.h
index b604a9186f8e..47fcdada5d25 100644
--- a/arch/s390/include/asm/dasd.h
+++ b/arch/s390/include/asm/dasd.h
@@ -80,6 +80,7 @@ typedef struct dasd_information2_t {
#define DASD_FEATURE_INITIAL_ONLINE 0x04
#define DASD_FEATURE_ERPLOG 0x08
#define DASD_FEATURE_FAILFAST 0x10
+#define DASD_FEATURE_FAILONSLCK 0x20
#define DASD_PARTN_BITS 2
diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
index 8f2067bc88c0..f16afe74464f 100644
--- a/drivers/s390/block/dasd.c
+++ b/drivers/s390/block/dasd.c
@@ -902,6 +902,16 @@ int dasd_start_IO(struct dasd_ccw_req *cqr)
return rc;
}
device = (struct dasd_device *) cqr->startdev;
+ if (((cqr->block &&
+ test_bit(DASD_FLAG_LOCK_STOLEN, &cqr->block->base->flags)) ||
+ test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags)) &&
+ !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
+ DBF_DEV_EVENT(DBF_DEBUG, device, "start_IO: return request %p "
+ "because of stolen lock", cqr);
+ cqr->status = DASD_CQR_ERROR;
+ cqr->intrc = -EPERM;
+ return -EPERM;
+ }
if (cqr->retries < 0) {
/* internal error 14 - start_IO run out of retries */
sprintf(errorstring, "14 %p", cqr);
@@ -1115,16 +1125,11 @@ void dasd_int_handler(struct ccw_device *cdev, unsigned long intparm,
}
now = get_clock();
-
- /* check for unsolicited interrupts */
cqr = (struct dasd_ccw_req *) intparm;
- if (!cqr || ((scsw_cc(&irb->scsw) == 1) &&
- (scsw_fctl(&irb->scsw) & SCSW_FCTL_START_FUNC) &&
- ((scsw_stctl(&irb->scsw) == SCSW_STCTL_STATUS_PEND) ||
- (scsw_stctl(&irb->scsw) == (SCSW_STCTL_STATUS_PEND |
- SCSW_STCTL_ALERT_STATUS))))) {
- if (cqr && cqr->status == DASD_CQR_IN_IO)
- cqr->status = DASD_CQR_QUEUED;
+ /* check for conditions that should be handled immediately */
+ if (!cqr ||
+ !(scsw_dstat(&irb->scsw) == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) &&
+ scsw_cstat(&irb->scsw) == 0)) {
if (cqr)
memcpy(&cqr->irb, irb, sizeof(*irb));
device = dasd_device_from_cdev_locked(cdev);
@@ -1135,17 +1140,14 @@ void dasd_int_handler(struct ccw_device *cdev, unsigned long intparm,
dasd_put_device(device);
return;
}
- device->discipline->dump_sense_dbf(device, irb,
- "unsolicited");
- if ((device->features & DASD_FEATURE_ERPLOG))
- device->discipline->dump_sense(device, cqr,
- irb);
- dasd_device_clear_timer(device);
- device->discipline->handle_unsolicited_interrupt(device,
- irb);
+ device->discipline->dump_sense_dbf(device, irb, "int");
+ if (device->features & DASD_FEATURE_ERPLOG)
+ device->discipline->dump_sense(device, cqr, irb);
+ device->discipline->check_for_device_change(device, cqr, irb);
dasd_put_device(device);
- return;
}
+ if (!cqr)
+ return;
device = (struct dasd_device *) cqr->startdev;
if (!device ||
@@ -1185,13 +1187,6 @@ void dasd_int_handler(struct ccw_device *cdev, unsigned long intparm,
struct dasd_ccw_req, devlist);
}
} else { /* error */
- memcpy(&cqr->irb, irb, sizeof(struct irb));
- /* log sense for every failed I/O to s390 debugfeature */
- dasd_log_sense_dbf(cqr, irb);
- if (device->features & DASD_FEATURE_ERPLOG) {
- dasd_log_sense(cqr, irb);
- }
-
/*
* If we don't want complex ERP for this request, then just
* reset this and retry it in the fastpath
@@ -1232,13 +1227,13 @@ enum uc_todo dasd_generic_uc_handler(struct ccw_device *cdev, struct irb *irb)
goto out;
if (test_bit(DASD_FLAG_OFFLINE, &device->flags) ||
device->state != device->target ||
- !device->discipline->handle_unsolicited_interrupt){
+ !device->discipline->check_for_device_change){
dasd_put_device(device);
goto out;
}
-
- dasd_device_clear_timer(device);
- device->discipline->handle_unsolicited_interrupt(device, irb);
+ if (device->discipline->dump_sense_dbf)
+ device->discipline->dump_sense_dbf(device, irb, "uc");
+ device->discipline->check_for_device_change(device, NULL, irb);
dasd_put_device(device);
out:
return UC_TODO_RETRY;
@@ -1659,7 +1654,12 @@ static int _dasd_sleep_on(struct dasd_ccw_req *maincqr, int interruptible)
continue;
if (cqr->status != DASD_CQR_FILLED) /* could be failed */
continue;
-
+ if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) &&
+ !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
+ cqr->status = DASD_CQR_FAILED;
+ cqr->intrc = -EPERM;
+ continue;
+ }
/* Non-temporary stop condition will trigger fail fast */
if (device->stopped & ~DASD_STOPPED_PENDING &&
test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
@@ -1667,7 +1667,6 @@ static int _dasd_sleep_on(struct dasd_ccw_req *maincqr, int interruptible)
cqr->status = DASD_CQR_FAILED;
continue;
}
-
/* Don't try to start requests if device is stopped */
if (interruptible) {
rc = wait_event_interruptible(
@@ -1752,13 +1751,18 @@ int dasd_sleep_on_immediatly(struct dasd_ccw_req *cqr)
int rc;
device = cqr->startdev;
+ if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) &&
+ !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
+ cqr->status = DASD_CQR_FAILED;
+ cqr->intrc = -EPERM;
+ return -EIO;
+ }
spin_lock_irq(get_ccwdev_lock(device->cdev));
rc = _dasd_term_running_cqr(device);
if (rc) {
spin_unlock_irq(get_ccwdev_lock(device->cdev));
return rc;
}
-
cqr->callback = dasd_wakeup_cb;
cqr->callback_data = DASD_SLEEPON_START_TAG;
cqr->status = DASD_CQR_QUEUED;
@@ -2062,6 +2066,13 @@ static void __dasd_block_start_head(struct dasd_block *block)
list_for_each_entry(cqr, &block->ccw_queue, blocklist) {
if (cqr->status != DASD_CQR_FILLED)
continue;
+ if (test_bit(DASD_FLAG_LOCK_STOLEN, &block->base->flags) &&
+ !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
+ cqr->status = DASD_CQR_FAILED;
+ cqr->intrc = -EPERM;
+ dasd_schedule_block_bh(block);
+ continue;
+ }
/* Non-temporary stop condition will trigger fail fast */
if (block->base->stopped & ~DASD_STOPPED_PENDING &&
test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
diff --git a/drivers/s390/block/dasd_devmap.c b/drivers/s390/block/dasd_devmap.c
index 0001df8ad3e6..47fc88692494 100644
--- a/drivers/s390/block/dasd_devmap.c
+++ b/drivers/s390/block/dasd_devmap.c
@@ -1127,6 +1127,103 @@ dasd_expires_store(struct device *dev, struct device_attribute *attr,
static DEVICE_ATTR(expires, 0644, dasd_expires_show, dasd_expires_store);
+static ssize_t dasd_reservation_policy_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct dasd_devmap *devmap;
+ int rc = 0;
+
+ devmap = dasd_find_busid(dev_name(dev));
+ if (IS_ERR(devmap)) {
+ rc = snprintf(buf, PAGE_SIZE, "ignore\n");
+ } else {
+ spin_lock(&dasd_devmap_lock);
+ if (devmap->features & DASD_FEATURE_FAILONSLCK)
+ rc = snprintf(buf, PAGE_SIZE, "fail\n");
+ else
+ rc = snprintf(buf, PAGE_SIZE, "ignore\n");
+ spin_unlock(&dasd_devmap_lock);
+ }
+ return rc;
+}
+
+static ssize_t dasd_reservation_policy_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct dasd_devmap *devmap;
+ int rc;
+
+ devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
+ if (IS_ERR(devmap))
+ return PTR_ERR(devmap);
+ rc = 0;
+ spin_lock(&dasd_devmap_lock);
+ if (sysfs_streq("ignore", buf))
+ devmap->features &= ~DASD_FEATURE_FAILONSLCK;
+ else if (sysfs_streq("fail", buf))
+ devmap->features |= DASD_FEATURE_FAILONSLCK;
+ else
+ rc = -EINVAL;
+ if (devmap->device)
+ devmap->device->features = devmap->features;
+ spin_unlock(&dasd_devmap_lock);
+ if (rc)
+ return rc;
+ else
+ return count;
+}
+
+static DEVICE_ATTR(reservation_policy, 0644,
+ dasd_reservation_policy_show, dasd_reservation_policy_store);
+
+static ssize_t dasd_reservation_state_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct dasd_device *device;
+ int rc = 0;
+
+ device = dasd_device_from_cdev(to_ccwdev(dev));
+ if (IS_ERR(device))
+ return snprintf(buf, PAGE_SIZE, "none\n");
+
+ if (test_bit(DASD_FLAG_IS_RESERVED, &device->flags))
+ rc = snprintf(buf, PAGE_SIZE, "reserved\n");
+ else if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags))
+ rc = snprintf(buf, PAGE_SIZE, "lost\n");
+ else
+ rc = snprintf(buf, PAGE_SIZE, "none\n");
+ dasd_put_device(device);
+ return rc;
+}
+
+static ssize_t dasd_reservation_state_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct dasd_device *device;
+ int rc = 0;
+
+ device = dasd_device_from_cdev(to_ccwdev(dev));
+ if (IS_ERR(device))
+ return -ENODEV;
+ if (sysfs_streq("reset", buf))
+ clear_bit(DASD_FLAG_LOCK_STOLEN, &device->flags);
+ else
+ rc = -EINVAL;
+ dasd_put_device(device);
+
+ if (rc)
+ return rc;
+ else
+ return count;
+}
+
+static DEVICE_ATTR(last_known_reservation_state, 0644,
+ dasd_reservation_state_show, dasd_reservation_state_store);
+
static struct attribute * dasd_attrs[] = {
&dev_attr_readonly.attr,
&dev_attr_discipline.attr,
@@ -1139,6 +1236,8 @@ static struct attribute * dasd_attrs[] = {
&dev_attr_erplog.attr,
&dev_attr_failfast.attr,
&dev_attr_expires.attr,
+ &dev_attr_reservation_policy.attr,
+ &dev_attr_last_known_reservation_state.attr,
NULL,
};
diff --git a/drivers/s390/block/dasd_eckd.c b/drivers/s390/block/dasd_eckd.c
index a1ebf5722ae5..46eafce3a0a6 100644
--- a/drivers/s390/block/dasd_eckd.c
+++ b/drivers/s390/block/dasd_eckd.c
@@ -817,6 +817,7 @@ static int dasd_eckd_read_conf_immediately(struct dasd_device *device,
dasd_eckd_fill_rcd_cqr(device, cqr, rcd_buffer, lpm);
clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
+ set_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags);
cqr->retries = 5;
rc = dasd_sleep_on_immediatly(cqr);
return rc;
@@ -1947,9 +1948,9 @@ dasd_eckd_erp_postaction(struct dasd_ccw_req * cqr)
return dasd_default_erp_postaction;
}
-
-static void dasd_eckd_handle_unsolicited_interrupt(struct dasd_device *device,
- struct irb *irb)
+static void dasd_eckd_check_for_device_change(struct dasd_device *device,
+ struct dasd_ccw_req *cqr,
+ struct irb *irb)
{
char mask;
char *sense = NULL;
@@ -1973,40 +1974,41 @@ static void dasd_eckd_handle_unsolicited_interrupt(struct dasd_device *device,
/* schedule worker to reload device */
dasd_reload_device(device);
}
-
dasd_generic_handle_state_change(device);
return;
}
- /* summary unit check */
sense = dasd_get_sense(irb);
- if (sense && (sense[7] == 0x0D) &&
+ if (!sense)
+ return;
+
+ /* summary unit check */
+ if ((sense[7] == 0x0D) &&
(scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK)) {
dasd_alias_handle_summary_unit_check(device, irb);
return;
}
/* service information message SIM */
- if (sense && !(sense[27] & DASD_SENSE_BIT_0) &&
+ if (!cqr && !(sense[27] & DASD_SENSE_BIT_0) &&
((sense[6] & DASD_SIM_SENSE) == DASD_SIM_SENSE)) {
dasd_3990_erp_handle_sim(device, sense);
- dasd_schedule_device_bh(device);
return;
}
- if ((scsw_cc(&irb->scsw) == 1) && !sense &&
- (scsw_fctl(&irb->scsw) == SCSW_FCTL_START_FUNC) &&
- (scsw_actl(&irb->scsw) == SCSW_ACTL_START_PEND) &&
- (scsw_stctl(&irb->scsw) == SCSW_STCTL_STATUS_PEND)) {
- /* fake irb do nothing, they are handled elsewhere */
- dasd_schedule_device_bh(device);
- return;
+ /* loss of device reservation is handled via base devices only
+ * as alias devices may be used with several bases
+ */
+ if (device->block && (sense[7] == 0x3F) &&
+ (scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK) &&
+ test_bit(DASD_FLAG_IS_RESERVED, &device->flags)) {
+ if (device->features & DASD_FEATURE_FAILONSLCK)
+ set_bit(DASD_FLAG_LOCK_STOLEN, &device->flags);
+ clear_bit(DASD_FLAG_IS_RESERVED, &device->flags);
+ dev_err(&device->cdev->dev,
+ "The device reservation was lost\n");
}
-
- dasd_schedule_device_bh(device);
- return;
-};
-
+}
static struct dasd_ccw_req *dasd_eckd_build_cp_cmd_single(
struct dasd_device *startdev,
@@ -2931,6 +2933,8 @@ dasd_eckd_release(struct dasd_device *device)
cqr->status = DASD_CQR_FILLED;
rc = dasd_sleep_on_immediatly(cqr);
+ if (!rc)
+ clear_bit(DASD_FLAG_IS_RESERVED, &device->flags);
if (useglobal)
mutex_unlock(&dasd_reserve_mutex);
@@ -2984,6 +2988,8 @@ dasd_eckd_reserve(struct dasd_device *device)
cqr->status = DASD_CQR_FILLED;
rc = dasd_sleep_on_immediatly(cqr);
+ if (!rc)
+ set_bit(DASD_FLAG_IS_RESERVED, &device->flags);
if (useglobal)
mutex_unlock(&dasd_reserve_mutex);
@@ -3036,6 +3042,8 @@ dasd_eckd_steal_lock(struct dasd_device *device)
cqr->status = DASD_CQR_FILLED;
rc = dasd_sleep_on_immediatly(cqr);
+ if (!rc)
+ set_bit(DASD_FLAG_IS_RESERVED, &device->flags);
if (useglobal)
mutex_unlock(&dasd_reserve_mutex);
@@ -3088,6 +3096,7 @@ static int dasd_eckd_snid(struct dasd_device *device,
cqr->memdev = device;
clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
+ set_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags);
cqr->retries = 5;
cqr->expires = 10 * HZ;
cqr->buildclk = get_clock();
@@ -3832,7 +3841,7 @@ static struct dasd_discipline dasd_eckd_discipline = {
.format_device = dasd_eckd_format_device,
.erp_action = dasd_eckd_erp_action,
.erp_postaction = dasd_eckd_erp_postaction,
- .handle_unsolicited_interrupt = dasd_eckd_handle_unsolicited_interrupt,
+ .check_for_device_change = dasd_eckd_check_for_device_change,
.build_cp = dasd_eckd_build_alias_cp,
.free_cp = dasd_eckd_free_alias_cp,
.dump_sense = dasd_eckd_dump_sense,
diff --git a/drivers/s390/block/dasd_eer.c b/drivers/s390/block/dasd_eer.c
index 83b4615a3b62..77f778b7b070 100644
--- a/drivers/s390/block/dasd_eer.c
+++ b/drivers/s390/block/dasd_eer.c
@@ -473,6 +473,7 @@ int dasd_eer_enable(struct dasd_device *device)
cqr->retries = 255;
cqr->expires = 10 * HZ;
clear_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
+ set_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags);
ccw = cqr->cpaddr;
ccw->cmd_code = DASD_ECKD_CCW_SNSS;
diff --git a/drivers/s390/block/dasd_fba.c b/drivers/s390/block/dasd_fba.c
index 86bacda2c5f6..be89b3a893da 100644
--- a/drivers/s390/block/dasd_fba.c
+++ b/drivers/s390/block/dasd_fba.c
@@ -233,24 +233,16 @@ dasd_fba_erp_postaction(struct dasd_ccw_req * cqr)
return NULL;
}
-static void dasd_fba_handle_unsolicited_interrupt(struct dasd_device *device,
- struct irb *irb)
+static void dasd_fba_check_for_device_change(struct dasd_device *device,
+ struct dasd_ccw_req *cqr,
+ struct irb *irb)
{
char mask;
/* first of all check for state change pending interrupt */
mask = DEV_STAT_ATTENTION | DEV_STAT_DEV_END | DEV_STAT_UNIT_EXCEP;
- if ((irb->scsw.cmd.dstat & mask) == mask) {
+ if ((irb->scsw.cmd.dstat & mask) == mask)
dasd_generic_handle_state_change(device);
- return;
- }
-
- /* check for unsolicited interrupts */
- DBF_DEV_EVENT(DBF_WARNING, device, "%s",
- "unsolicited interrupt received");
- device->discipline->dump_sense_dbf(device, irb, "unsolicited");
- dasd_schedule_device_bh(device);
- return;
};
static struct dasd_ccw_req *dasd_fba_build_cp(struct dasd_device * memdev,
@@ -605,7 +597,7 @@ static struct dasd_discipline dasd_fba_discipline = {
.handle_terminated_request = dasd_fba_handle_terminated_request,
.erp_action = dasd_fba_erp_action,
.erp_postaction = dasd_fba_erp_postaction,
- .handle_unsolicited_interrupt = dasd_fba_handle_unsolicited_interrupt,
+ .check_for_device_change = dasd_fba_check_for_device_change,
.build_cp = dasd_fba_build_cp,
.free_cp = dasd_fba_free_cp,
.dump_sense = dasd_fba_dump_sense,
diff --git a/drivers/s390/block/dasd_int.h b/drivers/s390/block/dasd_int.h
index ba038ef57606..df9f6999411d 100644
--- a/drivers/s390/block/dasd_int.h
+++ b/drivers/s390/block/dasd_int.h
@@ -232,6 +232,10 @@ struct dasd_ccw_req {
#define DASD_CQR_FLAGS_USE_ERP 0 /* use ERP for this request */
#define DASD_CQR_FLAGS_FAILFAST 1 /* FAILFAST */
#define DASD_CQR_VERIFY_PATH 2 /* path verification request */
+#define DASD_CQR_ALLOW_SLOCK 3 /* Try this request even when lock was
+ * stolen. Should not be combined with
+ * DASD_CQR_FLAGS_USE_ERP
+ */
/* Signature for error recovery functions. */
typedef struct dasd_ccw_req *(*dasd_erp_fn_t) (struct dasd_ccw_req *);
@@ -334,9 +338,9 @@ struct dasd_discipline {
void (*dump_sense) (struct dasd_device *, struct dasd_ccw_req *,
struct irb *);
void (*dump_sense_dbf) (struct dasd_device *, struct irb *, char *);
-
- void (*handle_unsolicited_interrupt) (struct dasd_device *,
- struct irb *);
+ void (*check_for_device_change) (struct dasd_device *,
+ struct dasd_ccw_req *,
+ struct irb *);
/* i/o control functions. */
int (*fill_geometry) (struct dasd_block *, struct hd_geometry *);
@@ -473,6 +477,9 @@ struct dasd_block {
* confuse this with the user specified
* read-only feature.
*/
+#define DASD_FLAG_IS_RESERVED 7 /* The device is reserved */
+#define DASD_FLAG_LOCK_STOLEN 8 /* The device lock was stolen */
+
void dasd_put_device_wake(struct dasd_device *);