2004-04-28 19:27:36

by Martin Schwidefsky

[permalink] [raw]
Subject: [PATCH] s390 (2/6): common i/o layer.

[PATCH] s390: common i/o layer.

From: Martin Schwidefsky <[email protected]>

Common i/o layer changes:
- Don't use bus ids in crw debug feature.
- Use cio_oper for oper notification to disconnected devices.
- Remove __get_subchannel_by_stsch.
- Make cio workqueue a single threaded workqueue.
- Introduce addiotnal cio_notify workqueue for device driver notification.
- Switch off path in vpm if cio_start returned -ENODEV.
- Fix rescan for new subchannels after a logical vary on.

diffstat:
drivers/s390/cio/chsc.c | 13 ++++++-------
drivers/s390/cio/css.c | 28 ++--------------------------
drivers/s390/cio/device.c | 34 +++++++++++++++++++++++++---------
drivers/s390/cio/device.h | 3 ++-
drivers/s390/cio/device_fsm.c | 32 +++++++++++++++++++-------------
drivers/s390/cio/device_pgid.c | 2 +-
6 files changed, 55 insertions(+), 57 deletions(-)

diff -urN linux-2.6/drivers/s390/cio/chsc.c linux-2.6-s390/drivers/s390/cio/chsc.c
--- linux-2.6/drivers/s390/cio/chsc.c Wed Apr 28 17:51:15 2004
+++ linux-2.6-s390/drivers/s390/cio/chsc.c Wed Apr 28 17:51:38 2004
@@ -1,7 +1,7 @@
/*
* drivers/s390/cio/chsc.c
* S/390 common I/O routines -- channel subsystem call
- * $Revision: 1.107 $
+ * $Revision: 1.110 $
*
* Copyright (C) 1999-2002 IBM Deutschland Entwicklung GmbH,
* IBM Corporation
@@ -148,7 +148,7 @@
*/
if (ssd_area->st > 3) { /* uhm, that looks strange... */
CIO_CRW_EVENT(0, "Strange subchannel type %d"
- " for sch %s\n", ssd_area->st, sch->dev.bus_id);
+ " for sch %04x\n", ssd_area->st, sch->irq);
/*
* There may have been a new subchannel type defined in the
* time since this code was written; since we don't know which
@@ -157,8 +157,8 @@
return 0;
} else {
const char *type[4] = {"I/O", "chsc", "message", "ADM"};
- CIO_CRW_EVENT(6, "ssd: sch %s is %s subchannel\n",
- sch->dev.bus_id, type[ssd_area->st]);
+ CIO_CRW_EVENT(6, "ssd: sch %04x is %s subchannel\n",
+ sch->irq, type[ssd_area->st]);

sch->ssd_info.valid = 1;
sch->ssd_info.type = ssd_area->st;
@@ -818,6 +818,8 @@
for (irq = 0; irq < __MAX_SUBCHANNELS; irq++) {
struct schib schib;

+ if (need_rescan)
+ break;
sch = get_subchannel_by_schid(irq);
if (sch) {
put_device(&sch->dev);
@@ -826,15 +828,12 @@
if (stsch(irq, &schib))
/* We're through */
break;
- if (need_rescan)
- continue;
/* Put it on the slow path. */
ret = css_enqueue_subchannel_slow(irq);
if (ret) {
css_clear_subchannel_slow_list();
need_rescan = 1;
}
- continue;
}
if (need_rescan || css_slow_subchannels_exist())
schedule_work(&varyonoff_work);
diff -urN linux-2.6/drivers/s390/cio/css.c linux-2.6-s390/drivers/s390/cio/css.c
--- linux-2.6/drivers/s390/cio/css.c Wed Apr 28 17:51:15 2004
+++ linux-2.6-s390/drivers/s390/cio/css.c Wed Apr 28 17:51:38 2004
@@ -1,7 +1,7 @@
/*
* drivers/s390/cio/css.c
* driver for channel subsystem
- * $Revision: 1.72 $
+ * $Revision: 1.73 $
*
* Copyright (C) 2002 IBM Deutschland Entwicklung GmbH,
* IBM Corporation
@@ -124,24 +124,6 @@
return ret;
}

-static struct subchannel *
-__get_subchannel_by_stsch(int irq)
-{
- struct subchannel *sch;
- int cc;
- struct schib schib;
-
- cc = stsch(irq, &schib);
- if (cc || !schib.pmcw.dnv)
- return NULL;
- sch = (struct subchannel *)(unsigned long)schib.pmcw.intparm;
- if (!sch)
- return NULL;
- if (get_device(&sch->dev))
- return sch;
- return NULL;
-}
-
struct subchannel *
get_subchannel_by_schid(int irq)
{
@@ -151,13 +133,8 @@

if (!get_bus(&css_bus_type))
return NULL;
-
- /* Try to get subchannel from pmcw first. */
- sch = __get_subchannel_by_stsch(irq);
- if (sch)
- goto out;
down_read(&css_bus_type.subsys.rwsem);
-
+ sch = NULL;
list_for_each(entry, &css_bus_type.devices.list) {
dev = get_device(container_of(entry,
struct device, bus_list));
@@ -170,7 +147,6 @@
sch = NULL;
}
up_read(&css_bus_type.subsys.rwsem);
-out:
put_bus(&css_bus_type);

return sch;
diff -urN linux-2.6/drivers/s390/cio/device.c linux-2.6-s390/drivers/s390/cio/device.c
--- linux-2.6/drivers/s390/cio/device.c Wed Apr 28 17:51:15 2004
+++ linux-2.6-s390/drivers/s390/cio/device.c Wed Apr 28 17:51:38 2004
@@ -1,7 +1,7 @@
/*
* drivers/s390/cio/device.c
* bus driver for ccw devices
- * $Revision: 1.113 $
+ * $Revision: 1.115 $
*
* Copyright (C) 2002 IBM Deutschland Entwicklung GmbH,
* IBM Corporation
@@ -138,6 +138,7 @@
};

struct workqueue_struct *ccw_device_work;
+struct workqueue_struct *ccw_device_notify_work;
static wait_queue_head_t ccw_device_init_wq;
static atomic_t ccw_device_init_count;

@@ -149,20 +150,30 @@
init_waitqueue_head(&ccw_device_init_wq);
atomic_set(&ccw_device_init_count, 0);

- ccw_device_work = create_workqueue("cio");
+ ccw_device_work = create_singlethread_workqueue("cio");
if (!ccw_device_work)
return -ENOMEM; /* FIXME: better errno ? */
-
+ ccw_device_notify_work = create_singlethread_workqueue("cio_notify");
+ if (!ccw_device_notify_work) {
+ ret = -ENOMEM; /* FIXME: better errno ? */
+ goto out_err;
+ }
if ((ret = bus_register (&ccw_bus_type)))
- return ret;
+ goto out_err;

if ((ret = driver_register(&io_subchannel_driver.drv)))
- return ret;
+ goto out_err;

wait_event(ccw_device_init_wq,
atomic_read(&ccw_device_init_count) == 0);
flush_workqueue(ccw_device_work);
return 0;
+out_err:
+ if (ccw_device_work)
+ destroy_workqueue(ccw_device_work);
+ if (ccw_device_notify_work)
+ destroy_workqueue(ccw_device_notify_work);
+ return ret;
}

static void __exit
@@ -170,6 +181,7 @@
{
driver_unregister(&io_subchannel_driver.drv);
bus_unregister(&ccw_bus_type);
+ destroy_workqueue(ccw_device_notify_work);
destroy_workqueue(ccw_device_work);
}

@@ -553,18 +565,21 @@
wake_up(&cdev->private->wait_q);
}

-static void
-device_call_sch_unregister(void *data)
+void
+ccw_device_call_sch_unregister(void *data)
{
struct ccw_device *cdev = data;
struct subchannel *sch;

sch = to_subchannel(cdev->dev.parent);
- device_unregister(&sch->dev);
+ /* Check if device is registered. */
+ if (!list_empty(&sch->dev.node))
+ device_unregister(&sch->dev);
/* Reset intparm to zeroes. */
sch->schib.pmcw.intparm = 0;
cio_modify(sch);
put_device(&cdev->dev);
+ put_device(&sch->dev);
}

/*
@@ -587,7 +602,7 @@
break;
sch = to_subchannel(cdev->dev.parent);
INIT_WORK(&cdev->private->kick_work,
- device_call_sch_unregister, (void *) cdev);
+ ccw_device_call_sch_unregister, (void *) cdev);
queue_work(ccw_device_work, &cdev->private->kick_work);
break;
case DEV_STATE_BOXED:
@@ -982,3 +997,4 @@
EXPORT_SYMBOL(get_ccwdev_by_busid);
EXPORT_SYMBOL(ccw_bus_type);
EXPORT_SYMBOL(ccw_device_work);
+EXPORT_SYMBOL(ccw_device_notify_work);
diff -urN linux-2.6/drivers/s390/cio/device.h linux-2.6-s390/drivers/s390/cio/device.h
--- linux-2.6/drivers/s390/cio/device.h Wed Apr 28 17:51:15 2004
+++ linux-2.6-s390/drivers/s390/cio/device.h Wed Apr 28 17:51:38 2004
@@ -66,6 +66,7 @@
}

extern struct workqueue_struct *ccw_device_work;
+extern struct workqueue_struct *ccw_device_notify_work;

void io_subchannel_recog_done(struct ccw_device *cdev);

@@ -73,7 +74,7 @@

int ccw_device_register(struct ccw_device *);
void ccw_device_do_unreg_rereg(void *);
-
+void ccw_device_call_sch_unregister(void *);

int ccw_device_recognition(struct ccw_device *);
int ccw_device_online(struct ccw_device *);
diff -urN linux-2.6/drivers/s390/cio/device_fsm.c linux-2.6-s390/drivers/s390/cio/device_fsm.c
--- linux-2.6/drivers/s390/cio/device_fsm.c Wed Apr 28 17:51:15 2004
+++ linux-2.6-s390/drivers/s390/cio/device_fsm.c Wed Apr 28 17:51:38 2004
@@ -328,7 +328,7 @@
cdev->private->flags.donotify = 0;
PREPARE_WORK(&cdev->private->kick_work, ccw_device_oper_notify,
(void *)cdev);
- queue_work(ccw_device_work, &cdev->private->kick_work);
+ queue_work(ccw_device_notify_work, &cdev->private->kick_work);
}
wake_up(&cdev->private->wait_q);

@@ -441,10 +441,13 @@
if (get_device(&sch->dev)) {
/* Driver doesn't want to keep device. */
cio_disable_subchannel(sch);
- device_unregister(&sch->dev);
- sch->schib.pmcw.intparm = 0;
- cio_modify(sch);
- put_device(&sch->dev);
+ if (get_device(&cdev->dev)) {
+ PREPARE_WORK(&cdev->private->kick_work,
+ ccw_device_call_sch_unregister,
+ (void *)cdev);
+ queue_work(ccw_device_work,
+ &cdev->private->kick_work);
+ }
}
} else {
cio_disable_subchannel(sch);
@@ -464,7 +467,7 @@
cdev = sch->dev.driver_data;
PREPARE_WORK(&cdev->private->kick_work,
ccw_device_nopath_notify, (void *)cdev);
- queue_work(ccw_device_work, &cdev->private->kick_work);
+ queue_work(ccw_device_notify_work, &cdev->private->kick_work);
}


@@ -482,7 +485,7 @@
default:
PREPARE_WORK(&cdev->private->kick_work,
ccw_device_nopath_notify, (void *)cdev);
- queue_work(ccw_device_work, &cdev->private->kick_work);
+ queue_work(ccw_device_notify_work, &cdev->private->kick_work);
ccw_device_done(cdev, DEV_STATE_NOT_OPER);
break;
}
@@ -722,7 +725,8 @@
if (!sch->lpm) {
PREPARE_WORK(&cdev->private->kick_work,
ccw_device_nopath_notify, (void *)cdev);
- queue_work(ccw_device_work, &cdev->private->kick_work);
+ queue_work(ccw_device_notify_work,
+ &cdev->private->kick_work);
} else
dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
} else if (cdev->handler)
@@ -798,7 +802,7 @@
if (!sch->lpm) {
PREPARE_WORK(&cdev->private->kick_work,
ccw_device_nopath_notify, (void *)cdev);
- queue_work(ccw_device_work, &cdev->private->kick_work);
+ queue_work(ccw_device_notify_work, &cdev->private->kick_work);
} else if (cdev->private->flags.doverify)
/* Start delayed path verification. */
ccw_device_online_verify(cdev, 0);
@@ -821,7 +825,8 @@
if (!sch->lpm) {
PREPARE_WORK(&cdev->private->kick_work,
ccw_device_nopath_notify, (void *)cdev);
- queue_work(ccw_device_work, &cdev->private->kick_work);
+ queue_work(ccw_device_notify_work,
+ &cdev->private->kick_work);
} else
dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
return;
@@ -871,7 +876,7 @@
if (!sch->lpm) {
PREPARE_WORK(&cdev->private->kick_work,
ccw_device_nopath_notify, (void *)cdev);
- queue_work(ccw_device_work, &cdev->private->kick_work);
+ queue_work(ccw_device_notify_work, &cdev->private->kick_work);
} else if (cdev->private->flags.doverify)
ccw_device_online_verify(cdev, 0);
}
@@ -894,7 +899,8 @@
if (!sch->lpm) {
PREPARE_WORK(&cdev->private->kick_work,
ccw_device_nopath_notify, (void *)cdev);
- queue_work(ccw_device_work, &cdev->private->kick_work);
+ queue_work(ccw_device_notify_work,
+ &cdev->private->kick_work);
} else
dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
return;
@@ -905,7 +911,7 @@
if (!sch->lpm) {
PREPARE_WORK(&cdev->private->kick_work,
ccw_device_nopath_notify, (void *)cdev);
- queue_work(ccw_device_work, &cdev->private->kick_work);
+ queue_work(ccw_device_notify_work, &cdev->private->kick_work);
} else if (cdev->private->flags.doverify)
/* Start delayed path verification. */
ccw_device_online_verify(cdev, 0);
diff -urN linux-2.6/drivers/s390/cio/device_pgid.c linux-2.6-s390/drivers/s390/cio/device_pgid.c
--- linux-2.6/drivers/s390/cio/device_pgid.c Sun Apr 4 05:37:23 2004
+++ linux-2.6-s390/drivers/s390/cio/device_pgid.c Wed Apr 28 17:51:38 2004
@@ -227,7 +227,7 @@
ret = cio_start (sch, cdev->private->iccws,
cdev->private->imask);
/* ret is 0, -EBUSY, -EACCES or -ENODEV */
- if (ret != -EACCES)
+ if ((ret != -EACCES) && (ret != -ENODEV))
return ret;
}
/* PGID command failed on this path. Switch it off. */