1 files changed, 46 insertions, 2 deletions

diff --git a/drivers/s390/cio/qdio_thinint.c b/drivers/s390/cio/qdio_thinint.c
index 9d1e7efb5bb..011eadea3ee 100644
--- a/drivers/s390/cio/qdio_thinint.c
+++ b/drivers/s390/cio/qdio_thinint.c
@@ -26,6 +26,13 @@
  */
 #define TIQDIO_NR_NONSHARED_IND         63
 #define TIQDIO_NR_INDICATORS            (TIQDIO_NR_NONSHARED_IND + 1)
+#define TIQDIO_SHARED_IND               63
+
+/* device state change indicators */
+struct indicator_t {
+        u32 ind;        /* u32 because of compare-and-swap performance */
+        atomic_t count; /* use count, 0 or 1 for non-shared indicators */
+};
 
 /* list of thin interrupt input queues */
 static LIST_HEAD(tiq_list);
@@ -34,7 +41,7 @@ static DEFINE_MUTEX(tiq_list_lock);
 /* adapter local summary indicator */
 static u8 *tiqdio_alsi;
 
-struct indicator_t *q_indicators;
+static struct indicator_t *q_indicators;
 
 u64 last_ai_time;
 
@@ -90,6 +97,43 @@ void tiqdio_remove_input_queues(struct qdio_irq *irq_ptr)
         synchronize_rcu();
 }
 
+static inline int has_multiple_inq_on_dsci(struct qdio_irq *irq_ptr)
+{
+        return irq_ptr->nr_input_qs > 1;
+}
+
+static inline int references_shared_dsci(struct qdio_irq *irq_ptr)
+{
+        return irq_ptr->dsci == &q_indicators[TIQDIO_SHARED_IND].ind;
+}
+
+static inline int shared_ind(struct qdio_irq *irq_ptr)
+{
+        return references_shared_dsci(irq_ptr) ||
+                has_multiple_inq_on_dsci(irq_ptr);
+}
+
+void clear_nonshared_ind(struct qdio_irq *irq_ptr)
+{
+        if (!is_thinint_irq(irq_ptr))
+                return;
+        if (shared_ind(irq_ptr))
+                return;
+        xchg(irq_ptr->dsci, 0);
+}
+
+int test_nonshared_ind(struct qdio_irq *irq_ptr)
+{
+        if (!is_thinint_irq(irq_ptr))
+                return 0;
+        if (shared_ind(irq_ptr))
+                return 0;
+        if (*irq_ptr->dsci)
+                return 1;
+        else
+                return 0;
+}
+
 static inline u32 clear_shared_ind(void)
 {
         if (!atomic_read(&q_indicators[TIQDIO_SHARED_IND].count))
@@ -119,7 +163,7 @@ static inline void tiqdio_call_inq_handlers(struct qdio_irq *irq)
                         q->u.in.queue_start_poll(q->irq_ptr->cdev, q->nr,
                                                  q->irq_ptr->int_parm);
                 } else {
-                        if (!shared_ind(q))
+                        if (!shared_ind(q->irq_ptr))
                                 xchg(q->irq_ptr->dsci, 0);
 
                         /*