[PATCH 6.1 060/451] s390/dasd: add autoquiesce feature

Sasha Levin
2024-03-24T23:13:08Z

From: Stefan Haberland <sth@linux.ibm.com>

[ Upstream commit 1cee2975bbabd89df1097c354867192106b058ea ]

Add the internal logic to check for autoquiesce triggers and handle
them.

Quiesce and resume are functions that tell Linux to stop/resume
issuing I/Os to a specific DASD.
The DASD driver allows a manual quiesce/resume via ioctl.

Autoquiesce will define an amount of triggers that will lead to
an automatic quiesce if a certain event occurs.
There is no automatic resume.

All events will be reported via DASD Extended Error Reporting (EER)
if configured.

Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Link: https://lore.kernel.org/r/20230405142017.2446986-3-sth@linux.ibm.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Stable-dep-of: c3116e62ddef ("s390/dasd: fix double module refcount decrement")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/s390/include/uapi/asm/dasd.h | 2 ++
drivers/s390/block/dasd.c | 60 ++++++++++++++++++++++---------
drivers/s390/block/dasd_eer.c | 1 +
drivers/s390/block/dasd_int.h | 2 ++
4 files changed, 48 insertions(+), 17 deletions(-)

diff --git a/arch/s390/include/uapi/asm/dasd.h b/arch/s390/include/uapi/asm/dasd.h
index 93d1ccd3304c7..9c49c3d67cd56 100644
--- a/arch/s390/include/uapi/asm/dasd.h
+++ b/arch/s390/include/uapi/asm/dasd.h
@@ -78,6 +78,7 @@ typedef struct dasd_information2_t {
* 0x040: give access to raw eckd data
* 0x080: enable discard support
* 0x100: enable autodisable for IFCC errors (default)
+ * 0x200: enable requeue of all requests on autoquiesce
*/
#define DASD_FEATURE_READONLY 0x001
#define DASD_FEATURE_USEDIAG 0x002
@@ -88,6 +89,7 @@ typedef struct dasd_information2_t {
#define DASD_FEATURE_USERAW 0x040
#define DASD_FEATURE_DISCARD 0x080
#define DASD_FEATURE_PATH_AUTODISABLE 0x100
+#define DASD_FEATURE_REQUEUEQUIESCE 0x200
#define DASD_FEATURE_DEFAULT DASD_FEATURE_PATH_AUTODISABLE

#define DASD_PARTN_BITS 2
diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
index f207de4a87a0f..2f6976671496f 100644
--- a/drivers/s390/block/dasd.c
+++ b/drivers/s390/block/dasd.c
@@ -73,7 +73,8 @@ static void dasd_profile_init(struct dasd_profile *, struct dentry *);
static void dasd_profile_exit(struct dasd_profile *);
static void dasd_hosts_init(struct dentry *, struct dasd_device *);
static void dasd_hosts_exit(struct dasd_device *);
-
+static int dasd_handle_autoquiesce(struct dasd_device *, struct dasd_ccw_req *,
+ unsigned int);
/*
* SECTION: Operations on the device structure.
*/
@@ -2327,7 +2328,7 @@ static int _dasd_sleep_on(struct dasd_ccw_req *maincqr, int interruptible)
/* 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))) {
+ !dasd_eer_enabled(device) && device->aq_mask == 0) {
cqr->status = DASD_CQR_FAILED;
cqr->intrc = -ENOLINK;
continue;
@@ -2803,20 +2804,18 @@ static void __dasd_process_block_ccw_queue(struct dasd_block *block,
dasd_log_sense(cqr, &cqr->irb);
}

- /* First of all call extended error reporting. */
- if (dasd_eer_enabled(base) &&
- cqr->status == DASD_CQR_FAILED) {
- dasd_eer_write(base, cqr, DASD_EER_FATALERROR);
-
- /* restart request */
+ /*
+ * First call extended error reporting and check for autoquiesce
+ */
+ spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
+ if (cqr->status == DASD_CQR_FAILED &&
+ dasd_handle_autoquiesce(base, cqr, DASD_EER_FATALERROR)) {
cqr->status = DASD_CQR_FILLED;
cqr->retries = 255;
- spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
- dasd_device_set_stop_bits(base, DASD_STOPPED_QUIESCE);
- spin_unlock_irqrestore(get_ccwdev_lock(base->cdev),
- flags);
+ spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
goto restart;
}
+ spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);

/* Process finished ERP request. */
if (cqr->refers) {
@@ -2858,7 +2857,7 @@ static void __dasd_block_start_head(struct dasd_block *block)
/* Non-temporary stop condition will trigger fail fast */
if (block->base->stopped & ~DASD_STOPPED_PENDING &&
test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
- (!dasd_eer_enabled(block->base))) {
+ !dasd_eer_enabled(block->base) && block->base->aq_mask == 0) {
cqr->status = DASD_CQR_FAILED;
cqr->intrc = -ENOLINK;
dasd_schedule_block_bh(block);
@@ -3682,8 +3681,8 @@ int dasd_generic_last_path_gone(struct dasd_device *device)
dev_warn(&device->cdev->dev, "No operational channel path is left "
"for the device\n");
DBF_DEV_EVENT(DBF_WARNING, device, "%s", "last path gone");
- /* First of all call extended error reporting. */
- dasd_eer_write(device, NULL, DASD_EER_NOPATH);
+ /* First call extended error reporting and check for autoquiesce. */
+ dasd_handle_autoquiesce(device, NULL, DASD_EER_NOPATH);

if (device->state < DASD_STATE_BASIC)
return 0;
@@ -3815,7 +3814,8 @@ void dasd_generic_path_event(struct ccw_device *cdev, int *path_event)
"No verified channel paths remain for the device\n");
DBF_DEV_EVENT(DBF_WARNING, device,
"%s", "last verified path gone");
- dasd_eer_write(device, NULL, DASD_EER_NOPATH);
+ /* First call extended error reporting and check for autoquiesce. */
+ dasd_handle_autoquiesce(device, NULL, DASD_EER_NOPATH);
dasd_device_set_stop_bits(device,
DASD_STOPPED_DC_WAIT);
}
@@ -3837,7 +3837,8 @@ EXPORT_SYMBOL_GPL(dasd_generic_verify_path);
void dasd_generic_space_exhaust(struct dasd_device *device,
struct dasd_ccw_req *cqr)
{
- dasd_eer_write(device, NULL, DASD_EER_NOSPC);
+ /* First call extended error reporting and check for autoquiesce. */
+ dasd_handle_autoquiesce(device, NULL, DASD_EER_NOSPC);

if (device->state < DASD_STATE_BASIC)
return;
@@ -3931,6 +3932,31 @@ void dasd_schedule_requeue(struct dasd_device *device)
}
EXPORT_SYMBOL(dasd_schedule_requeue);

+static int dasd_handle_autoquiesce(struct dasd_device *device,
+ struct dasd_ccw_req *cqr,
+ unsigned int reason)
+{
+ /* in any case write eer message with reason */
+ if (dasd_eer_enabled(device))
+ dasd_eer_write(device, cqr, reason);
+
+ if (!test_bit(reason, &device->aq_mask))
+ return 0;
+
+ /* notify eer about autoquiesce */
+ if (dasd_eer_enabled(device))
+ dasd_eer_write(device, NULL, DASD_EER_AUTOQUIESCE);
+
+ pr_info("%s: The DASD has been put in the quiesce state\n",
+ dev_name(&device->cdev->dev));
+ dasd_device_set_stop_bits(device, DASD_STOPPED_QUIESCE);
+
+ if (device->features & DASD_FEATURE_REQUEUEQUIESCE)
+ dasd_schedule_requeue(device);
+
+ return 1;
+}
+
static struct dasd_ccw_req *dasd_generic_build_rdc(struct dasd_device *device,
int rdc_buffer_size,
int magic)
diff --git a/drivers/s390/block/dasd_eer.c b/drivers/s390/block/dasd_eer.c
index d4d31cd11d261..d16c699b9ac6d 100644
--- a/drivers/s390/block/dasd_eer.c
+++ b/drivers/s390/block/dasd_eer.c
@@ -387,6 +387,7 @@ void dasd_eer_write(struct dasd_device *device, struct dasd_ccw_req *cqr,
break;
case DASD_EER_NOPATH:
case DASD_EER_NOSPC:
+ case DASD_EER_AUTOQUIESCE:
dasd_eer_write_standard_trigger(device, NULL, id);
break;
case DASD_EER_STATECHANGE:
diff --git a/drivers/s390/block/dasd_int.h b/drivers/s390/block/dasd_int.h
index f50932518f83a..00bcd177264ac 100644
--- a/drivers/s390/block/dasd_int.h
+++ b/drivers/s390/block/dasd_int.h
@@ -464,6 +464,7 @@ extern struct dasd_discipline *dasd_diag_discipline_pointer;
#define DASD_EER_STATECHANGE 3
#define DASD_EER_PPRCSUSPEND 4
#define DASD_EER_NOSPC 5
+#define DASD_EER_AUTOQUIESCE 31

/* DASD path handling */

@@ -641,6 +642,7 @@ struct dasd_device {
struct dasd_format_entry format_entry;
struct kset *paths_info;
struct dasd_copy_relation *copy;
+ unsigned long aq_mask;
};

struct dasd_block {
--
2.43.0