1 files changed, 89 insertions, 64 deletions

diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c
index b4d572f65f0..0268e5fd59b 100644
--- a/drivers/s390/cio/css.c
+++ b/drivers/s390/cio/css.c
@@ -69,7 +69,8 @@ static int call_fn_known_sch(struct device *dev, void *data)
 	struct cb_data *cb = data;
 	int rc = 0;
 
-	idset_sch_del(cb->set, sch->schid);
+	if (cb->set)
+		idset_sch_del(cb->set, sch->schid);
 	if (cb->fn_known_sch)
 		rc = cb->fn_known_sch(sch, cb->data);
 	return rc;
@@ -115,6 +116,13 @@ int for_each_subchannel_staged(int (*fn_known)(struct subchannel *, void *),
 	cb.fn_known_sch = fn_known;
 	cb.fn_unknown_sch = fn_unknown;
 
+	if (fn_known && !fn_unknown) {
+		/* Skip idset allocation in case of known-only loop. */
+		cb.set = NULL;
+		return bus_for_each_dev(&css_bus_type, NULL, &cb,
+					call_fn_known_sch);
+	}
+
 	cb.set = idset_sch_new();
 	if (!cb.set)
 		/* fall back to brute force scanning in case of oom */
@@ -137,37 +145,53 @@ out:
 
 static void css_sch_todo(struct work_struct *work);
 
-static struct subchannel *
-css_alloc_subchannel(struct subchannel_id schid)
+static int css_sch_create_locks(struct subchannel *sch)
+{
+	sch->lock = kmalloc(sizeof(*sch->lock), GFP_KERNEL);
+	if (!sch->lock)
+		return -ENOMEM;
+
+	spin_lock_init(sch->lock);
+	mutex_init(&sch->reg_mutex);
+
+	return 0;
+}
+
+static void css_subchannel_release(struct device *dev)
+{
+	struct subchannel *sch = to_subchannel(dev);
+
+	sch->config.intparm = 0;
+	cio_commit_config(sch);
+	kfree(sch->lock);
+	kfree(sch);
+}
+
+struct subchannel *css_alloc_subchannel(struct subchannel_id schid)
 {
 	struct subchannel *sch;
 	int ret;
 
-	sch = kmalloc (sizeof (*sch), GFP_KERNEL | GFP_DMA);
-	if (sch == NULL)
+	sch = kzalloc(sizeof(*sch), GFP_KERNEL | GFP_DMA);
+	if (!sch)
 		return ERR_PTR(-ENOMEM);
-	ret = cio_validate_subchannel (sch, schid);
-	if (ret < 0) {
-		kfree(sch);
-		return ERR_PTR(ret);
-	}
+
+	ret = cio_validate_subchannel(sch, schid);
+	if (ret < 0)
+		goto err;
+
+	ret = css_sch_create_locks(sch);
+	if (ret)
+		goto err;
+
 	INIT_WORK(&sch->todo_work, css_sch_todo);
+	sch->dev.release = &css_subchannel_release;
+	device_initialize(&sch->dev);
 	return sch;
-}
 
-static void
-css_subchannel_release(struct device *dev)
-{
-	struct subchannel *sch;
-
-	sch = to_subchannel(dev);
-	if (!cio_is_console(sch->schid)) {
-		/* Reset intparm to zeroes. */
-		sch->config.intparm = 0;
-		cio_commit_config(sch);
-		kfree(sch->lock);
-		kfree(sch);
-	}
+err:
+	kfree(sch);
+	return ERR_PTR(ret);
 }
 
 static int css_sch_device_register(struct subchannel *sch)
@@ -177,7 +201,7 @@ static int css_sch_device_register(struct subchannel *sch)
 	mutex_lock(&sch->reg_mutex);
 	dev_set_name(&sch->dev, "0.%x.%04x", sch->schid.ssid,
 		     sch->schid.sch_no);
-	ret = device_register(&sch->dev);
+	ret = device_add(&sch->dev);
 	mutex_unlock(&sch->reg_mutex);
 	return ret;
 }
@@ -228,16 +252,11 @@ void css_update_ssd_info(struct subchannel *sch)
 {
 	int ret;
 
-	if (cio_is_console(sch->schid)) {
-		/* Console is initialized too early for functions requiring
-		 * memory allocation. */
+	ret = chsc_get_ssd_info(sch->schid, &sch->ssd_info);
+	if (ret)
 		ssd_from_pmcw(&sch->ssd_info, &sch->schib.pmcw);
-	} else {
-		ret = chsc_get_ssd_info(sch->schid, &sch->ssd_info);
-		if (ret)
-			ssd_from_pmcw(&sch->ssd_info, &sch->schib.pmcw);
-		ssd_register_chpids(&sch->ssd_info);
-	}
+
+	ssd_register_chpids(&sch->ssd_info);
 }
 
 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
@@ -275,14 +294,13 @@ static const struct attribute_group *default_subch_attr_groups[] = {
 	NULL,
 };
 
-static int css_register_subchannel(struct subchannel *sch)
+int css_register_subchannel(struct subchannel *sch)
 {
 	int ret;
 
 	/* Initialize the subchannel structure */
 	sch->dev.parent = &channel_subsystems[0]->device;
 	sch->dev.bus = &css_bus_type;
-	sch->dev.release = &css_subchannel_release;
 	sch->dev.groups = default_subch_attr_groups;
 	/*
 	 * We don't want to generate uevents for I/O subchannels that don't
@@ -314,23 +332,19 @@ static int css_register_subchannel(struct subchannel *sch)
 	return ret;
 }
 
-int css_probe_device(struct subchannel_id schid)
+static int css_probe_device(struct subchannel_id schid)
 {
-	int ret;
 	struct subchannel *sch;
+	int ret;
+
+	sch = css_alloc_subchannel(schid);
+	if (IS_ERR(sch))
+		return PTR_ERR(sch);
 
-	if (cio_is_console(schid))
-		sch = cio_get_console_subchannel();
-	else {
-		sch = css_alloc_subchannel(schid);
-		if (IS_ERR(sch))
-			return PTR_ERR(sch);
-	}
 	ret = css_register_subchannel(sch);
-	if (ret) {
-		if (!cio_is_console(schid))
-			put_device(&sch->dev);
-	}
+	if (ret)
+		put_device(&sch->dev);
+
 	return ret;
 }
 
@@ -377,7 +391,11 @@ static int css_evaluate_new_subchannel(struct subchannel_id schid, int slow)
 		/* Will be done on the slow path. */
 		return -EAGAIN;
 	}
-	if (stsch_err(schid, &schib) || !css_sch_is_valid(&schib)) {
+	if (stsch_err(schid, &schib)) {
+		/* Subchannel is not provided. */
+		return -ENXIO;
+	}
+	if (!css_sch_is_valid(&schib)) {
 		/* Unusable - ignore. */
 		return 0;
 	}
@@ -536,10 +554,16 @@ static int slow_eval_unknown_fn(struct subchannel_id schid, void *data)
 		case -ENOMEM:
 		case -EIO:
 			/* These should abort looping */
+			spin_lock_irq(&slow_subchannel_lock);
+			idset_sch_del_subseq(slow_subchannel_set, schid);
+			spin_unlock_irq(&slow_subchannel_lock);
 			break;
 		default:
 			rc = 0;
 		}
+		/* Allow scheduling here since the containing loop might
+		 * take a while.  */
+		cond_resched();
 	}
 	return rc;
 }
@@ -559,7 +583,7 @@ static void css_slow_path_func(struct work_struct *unused)
 	spin_unlock_irqrestore(&slow_subchannel_lock, flags);
 }
 
-static DECLARE_WORK(slow_path_work, css_slow_path_func);
+static DECLARE_DELAYED_WORK(slow_path_work, css_slow_path_func);
 struct workqueue_struct *cio_work_q;
 
 void css_schedule_eval(struct subchannel_id schid)
@@ -569,7 +593,7 @@ void css_schedule_eval(struct subchannel_id schid)
 	spin_lock_irqsave(&slow_subchannel_lock, flags);
 	idset_sch_add(slow_subchannel_set, schid);
 	atomic_set(&css_eval_scheduled, 1);
-	queue_work(cio_work_q, &slow_path_work);
+	queue_delayed_work(cio_work_q, &slow_path_work, 0);
 	spin_unlock_irqrestore(&slow_subchannel_lock, flags);
 }
 
@@ -580,7 +604,7 @@ void css_schedule_eval_all(void)
 	spin_lock_irqsave(&slow_subchannel_lock, flags);
 	idset_fill(slow_subchannel_set);
 	atomic_set(&css_eval_scheduled, 1);
-	queue_work(cio_work_q, &slow_path_work);
+	queue_delayed_work(cio_work_q, &slow_path_work, 0);
 	spin_unlock_irqrestore(&slow_subchannel_lock, flags);
 }
 
@@ -593,7 +617,7 @@ static int __unset_registered(struct device *dev, void *data)
 	return 0;
 }
 
-static void css_schedule_eval_all_unreg(void)
+void css_schedule_eval_all_unreg(unsigned long delay)
 {
 	unsigned long flags;
 	struct idset *unreg_set;
@@ -611,7 +635,7 @@ static void css_schedule_eval_all_unreg(void)
 	spin_lock_irqsave(&slow_subchannel_lock, flags);
 	idset_add_set(slow_subchannel_set, unreg_set);
 	atomic_set(&css_eval_scheduled, 1);
-	queue_work(cio_work_q, &slow_path_work);
+	queue_delayed_work(cio_work_q, &slow_path_work, delay);
 	spin_unlock_irqrestore(&slow_subchannel_lock, flags);
 	idset_free(unreg_set);
 }
@@ -624,7 +648,8 @@ void css_wait_for_slow_path(void)
 /* Schedule reprobing of all unregistered subchannels. */
 void css_schedule_reprobe(void)
 {
-	css_schedule_eval_all_unreg();
+	/* Schedule with a delay to allow merging of subsequent calls. */
+	css_schedule_eval_all_unreg(1 * HZ);
 }
 EXPORT_SYMBOL_GPL(css_schedule_reprobe);
 
@@ -729,7 +754,7 @@ css_cm_enable_store(struct device *dev, struct device_attribute *attr,
 	int ret;
 	unsigned long val;
 
-	ret = strict_strtoul(buf, 16, &val);
+	ret = kstrtoul(buf, 16, &val);
 	if (ret)
 		return ret;
 	mutex_lock(&css->mutex);
@@ -765,7 +790,7 @@ static int __init setup_css(int nr)
 	css->pseudo_subchannel->dev.release = css_subchannel_release;
 	dev_set_name(&css->pseudo_subchannel->dev, "defunct");
 	mutex_init(&css->pseudo_subchannel->reg_mutex);
-	ret = cio_create_sch_lock(css->pseudo_subchannel);
+	ret = css_sch_create_locks(css->pseudo_subchannel);
 	if (ret) {
 		kfree(css->pseudo_subchannel);
 		return ret;
@@ -775,7 +800,7 @@ static int __init setup_css(int nr)
 	css->cssid = nr;
 	dev_set_name(&css->device, "css%x", nr);
 	css->device.release = channel_subsystem_release;
-	tod_high = (u32) (get_clock() >> 32);
+	tod_high = (u32) (get_tod_clock() >> 32);
 	css_generate_pgid(css, tod_high);
 	return 0;
 }
@@ -865,8 +890,7 @@ static struct notifier_block css_power_notifier = {
 
 /*
  * Now that the driver core is running, we can setup our channel subsystem.
- * The struct subchannel's are created during probing (except for the
- * static console subchannel).
+ * The struct subchannel's are created during probing.
  */
 static int __init css_bus_init(void)
 {
@@ -1045,6 +1069,8 @@ int css_complete_work(void)
  */
 static int __init channel_subsystem_init_sync(void)
 {
+	/* Register subchannels which are already in use. */
+	cio_register_early_subchannels();
 	/* Start initial subchannel evaluation. */
 	css_schedule_eval_all();
 	css_complete_work();
@@ -1060,9 +1086,8 @@ void channel_subsystem_reinit(void)
 	chsc_enable_facility(CHSC_SDA_OC_MSS);
 	chp_id_for_each(&chpid) {
 		chp = chpid_to_chp(chpid);
-		if (!chp)
-			continue;
-		chsc_determine_base_channel_path_desc(chpid, &chp->desc);
+		if (chp)
+			chp_update_desc(chp);
 	}
 }