qdio: support asynchronous delivery of storage blocks

This patch introduces support for asynchronous delivery of storage blocks for
Hipersockets. Upper layers may exploit this functionality to reuse SBALs for
which the delivery status is still pending.

Signed-off-by: Einar Lueck <elelueck@de.ibm.com>
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 50 insertions, 38 deletions

diff --git a/drivers/s390/cio/qdio_thinint.c b/drivers/s390/cio/qdio_thinint.c
index 2a1d4df..a3e3949 100644
--- a/drivers/s390/cio/qdio_thinint.c
+++ b/drivers/s390/cio/qdio_thinint.c
@@ -67,12 +67,9 @@ static void put_indicator(u32 *addr)
 
 void tiqdio_add_input_queues(struct qdio_irq *irq_ptr)
 {
-	struct qdio_q *q;
-	int i;
-
 	mutex_lock(&tiq_list_lock);
-	for_each_input_queue(irq_ptr, q, i)
-		list_add_rcu(&q->entry, &tiq_list);
+	BUG_ON(irq_ptr->nr_input_qs < 1);
+	list_add_rcu(&irq_ptr->input_qs[0]->entry, &tiq_list);
 	mutex_unlock(&tiq_list_lock);
 	xchg(irq_ptr->dsci, 1 << 7);
 }
@@ -80,19 +77,17 @@ void tiqdio_add_input_queues(struct qdio_irq *irq_ptr)
 void tiqdio_remove_input_queues(struct qdio_irq *irq_ptr)
 {
 	struct qdio_q *q;
-	int i;
 
-	for (i = 0; i < irq_ptr->nr_input_qs; i++) {
-		q = irq_ptr->input_qs[i];
-		/* if establish triggered an error */
-		if (!q || !q->entry.prev || !q->entry.next)
-			continue;
+	BUG_ON(irq_ptr->nr_input_qs < 1);
+	q = irq_ptr->input_qs[0];
+	/* if establish triggered an error */
+	if (!q || !q->entry.prev || !q->entry.next)
+		return;
 
-		mutex_lock(&tiq_list_lock);
-		list_del_rcu(&q->entry);
-		mutex_unlock(&tiq_list_lock);
-		synchronize_rcu();
-	}
+	mutex_lock(&tiq_list_lock);
+	list_del_rcu(&q->entry);
+	mutex_unlock(&tiq_list_lock);
+	synchronize_rcu();
 }
 
 static inline u32 clear_shared_ind(void)
@@ -102,6 +97,40 @@ static inline u32 clear_shared_ind(void)
 	return xchg(&q_indicators[TIQDIO_SHARED_IND].ind, 0);
 }
 
+static inline void tiqdio_call_inq_handlers(struct qdio_irq *irq)
+{
+	struct qdio_q *q;
+	int i;
+
+	for_each_input_queue(irq, q, i) {
+		if (!references_shared_dsci(irq) &&
+		    has_multiple_inq_on_dsci(irq))
+			xchg(q->irq_ptr->dsci, 0);
+
+		if (q->u.in.queue_start_poll) {
+			/* skip if polling is enabled or already in work */
+			if (test_and_set_bit(QDIO_QUEUE_IRQS_DISABLED,
+					     &q->u.in.queue_irq_state)) {
+				qperf_inc(q, int_discarded);
+				continue;
+			}
+
+			/* avoid dsci clear here, done after processing */
+			q->u.in.queue_start_poll(q->irq_ptr->cdev, q->nr,
+						 q->irq_ptr->int_parm);
+		} else {
+			if (!shared_ind(q))
+				xchg(q->irq_ptr->dsci, 0);
+
+			/*
+			 * Call inbound processing but not directly
+			 * since that could starve other thinint queues.
+			 */
+			tasklet_schedule(&q->tasklet);
+		}
+	}
+}
+
 /**
  * tiqdio_thinint_handler - thin interrupt handler for qdio
  * @alsi: pointer to adapter local summary indicator
@@ -120,35 +149,18 @@ static void tiqdio_thinint_handler(void *alsi, void *data)
 
 	/* check for work on all inbound thinint queues */
 	list_for_each_entry_rcu(q, &tiq_list, entry) {
+		struct qdio_irq *irq;
 
 		/* only process queues from changed sets */
-		if (unlikely(shared_ind(q->irq_ptr->dsci))) {
+		irq = q->irq_ptr;
+		if (unlikely(references_shared_dsci(irq))) {
 			if (!si_used)
 				continue;
-		} else if (!*q->irq_ptr->dsci)
+		} else if (!*irq->dsci)
 			continue;
 
-		if (q->u.in.queue_start_poll) {
-			/* skip if polling is enabled or already in work */
-			if (test_and_set_bit(QDIO_QUEUE_IRQS_DISABLED,
-					     &q->u.in.queue_irq_state)) {
-				qperf_inc(q, int_discarded);
-				continue;
-			}
+		tiqdio_call_inq_handlers(irq);
 
-			/* avoid dsci clear here, done after processing */
-			q->u.in.queue_start_poll(q->irq_ptr->cdev, q->nr,
-						 q->irq_ptr->int_parm);
-		} else {
-			/* only clear it if the indicator is non-shared */
-			if (!shared_ind(q->irq_ptr->dsci))
-				xchg(q->irq_ptr->dsci, 0);
-			/*
-			 * Call inbound processing but not directly
-			 * since that could starve other thinint queues.
-			 */
-			tasklet_schedule(&q->tasklet);
-		}
 		qperf_inc(q, adapter_int);
 	}
 	rcu_read_unlock();