1 files changed, 126 insertions, 134 deletions

diff --git a/drivers/s390/cio/qdio_thinint.c b/drivers/s390/cio/qdio_thinint.c
index 752dbee06af..5d06253c2a7 100644
--- a/drivers/s390/cio/qdio_thinint.c
+++ b/drivers/s390/cio/qdio_thinint.c
@@ -1,14 +1,13 @@
 /*
- * linux/drivers/s390/cio/thinint_qdio.c
- *
- * Copyright 2000,2009 IBM Corp.
+ * Copyright IBM Corp. 2000, 2009
  * Author(s): Utz Bacher <utz.bacher@de.ibm.com>
  *	      Cornelia Huck <cornelia.huck@de.ibm.com>
  *	      Jan Glauber <jang@linux.vnet.ibm.com>
  */
 #include <linux/io.h>
 #include <linux/slab.h>
-#include <asm/atomic.h>
+#include <linux/kernel_stat.h>
+#include <linux/atomic.h>
 #include <asm/debug.h>
 #include <asm/qdio.h>
 #include <asm/airq.h>
@@ -25,31 +24,29 @@
  */
 #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);
-DEFINE_MUTEX(tiq_list_lock);
-
-/* adapter local summary indicator */
-static u8 *tiqdio_alsi;
+static DEFINE_MUTEX(tiq_list_lock);
 
-struct indicator_t *q_indicators;
+/* Adapter interrupt definitions */
+static void tiqdio_thinint_handler(struct airq_struct *airq);
 
-static int css_qdio_omit_svs;
+static struct airq_struct tiqdio_airq = {
+	.handler = tiqdio_thinint_handler,
+	.isc = QDIO_AIRQ_ISC,
+};
 
-static u64 last_ai_time;
+static struct indicator_t *q_indicators;
 
-static inline unsigned long do_clear_global_summary(void)
-{
-	register unsigned long __fn asm("1") = 3;
-	register unsigned long __tmp asm("2");
-	register unsigned long __time asm("3");
-
-	asm volatile(
-		"	.insn	rre,0xb2650000,2,0"
-		: "+d" (__fn), "=d" (__tmp), "=d" (__time));
-	return __time;
-}
+u64 last_ai_time;
 
 /* returns addr for the device state change indicator */
 static u32 *get_indicator(void)
@@ -80,16 +77,8 @@ static void put_indicator(u32 *addr)
 
 void tiqdio_add_input_queues(struct qdio_irq *irq_ptr)
 {
-	struct qdio_q *q;
-	int i;
-
-	/* No TDD facility? If we must use SIGA-s we can also omit SVS. */
-	if (!css_qdio_omit_svs && irq_ptr->siga_flag.sync)
-		css_qdio_omit_svs = 1;
-
 	mutex_lock(&tiq_list_lock);
-	for_each_input_queue(irq_ptr, q, i)
-		list_add_rcu(&q->entry, &tiq_list);
+	list_add_rcu(&irq_ptr->input_qs[0]->entry, &tiq_list);
 	mutex_unlock(&tiq_list_lock);
 	xchg(irq_ptr->dsci, 1 << 7);
 }
@@ -97,57 +86,71 @@ 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;
+	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 int shared_ind_used(void)
+static inline int has_multiple_inq_on_dsci(struct qdio_irq *irq_ptr)
 {
-	return atomic_read(&q_indicators[TIQDIO_SHARED_IND].count);
+	return irq_ptr->nr_input_qs > 1;
 }
 
-/**
- * tiqdio_thinint_handler - thin interrupt handler for qdio
- * @alsi: pointer to adapter local summary indicator
- * @data: NULL
- */
-static void tiqdio_thinint_handler(void *alsi, void *data)
+static inline int references_shared_dsci(struct qdio_irq *irq_ptr)
 {
-	struct qdio_q *q;
+	return irq_ptr->dsci == &q_indicators[TIQDIO_SHARED_IND].ind;
+}
 
-	last_ai_time = S390_lowcore.int_clock;
+static inline int shared_ind(struct qdio_irq *irq_ptr)
+{
+	return references_shared_dsci(irq_ptr) ||
+		has_multiple_inq_on_dsci(irq_ptr);
+}
 
-	/*
-	 * SVS only when needed: issue SVS to benefit from iqdio interrupt
-	 * avoidance (SVS clears adapter interrupt suppression overwrite).
-	 */
-	if (!css_qdio_omit_svs)
-		do_clear_global_summary();
+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);
+}
 
-	/* reset local summary indicator */
-	if (shared_ind_used())
-		xchg(tiqdio_alsi, 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;
+}
 
-	/* protect tiq_list entries, only changed in activate or shutdown */
-	rcu_read_lock();
+static inline u32 clear_shared_ind(void)
+{
+	if (!atomic_read(&q_indicators[TIQDIO_SHARED_IND].count))
+		return 0;
+	return xchg(&q_indicators[TIQDIO_SHARED_IND].ind, 0);
+}
 
-	/* check for work on all inbound thinint queues */
-	list_for_each_entry_rcu(q, &tiq_list, entry) {
+static inline void tiqdio_call_inq_handlers(struct qdio_irq *irq)
+{
+	struct qdio_q *q;
+	int i;
 
-		/* only process queues from changed sets */
-		if (!*q->irq_ptr->dsci)
-			continue;
+	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 */
@@ -161,79 +164,80 @@ static void tiqdio_thinint_handler(void *alsi, void *data)
 			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))
 				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();
+}
+
+/**
+ * tiqdio_thinint_handler - thin interrupt handler for qdio
+ * @alsi: pointer to adapter local summary indicator
+ * @data: NULL
+ */
+static void tiqdio_thinint_handler(struct airq_struct *airq)
+{
+	u32 si_used = clear_shared_ind();
+	struct qdio_q *q;
 
-	/*
-	 * If the shared indicator was used clear it now after all queues
-	 * were processed.
-	 */
-	if (shared_ind_used()) {
-		xchg(&q_indicators[TIQDIO_SHARED_IND].ind, 0);
+	last_ai_time = S390_lowcore.int_clock;
+	inc_irq_stat(IRQIO_QAI);
 
-		/* prevent racing */
-		if (*tiqdio_alsi)
-			xchg(&q_indicators[TIQDIO_SHARED_IND].ind, 1 << 7);
+	/* protect tiq_list entries, only changed in activate or shutdown */
+	rcu_read_lock();
+
+	/* 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 */
+		irq = q->irq_ptr;
+		if (unlikely(references_shared_dsci(irq))) {
+			if (!si_used)
+				continue;
+		} else if (!*irq->dsci)
+			continue;
+
+		tiqdio_call_inq_handlers(irq);
+
+		qperf_inc(q, adapter_int);
 	}
+	rcu_read_unlock();
 }
 
 static int set_subchannel_ind(struct qdio_irq *irq_ptr, int reset)
 {
-	struct scssc_area *scssc_area;
+	struct chsc_scssc_area *scssc = (void *)irq_ptr->chsc_page;
+	u64 summary_indicator_addr, subchannel_indicator_addr;
 	int rc;
 
-	scssc_area = (struct scssc_area *)irq_ptr->chsc_page;
-	memset(scssc_area, 0, PAGE_SIZE);
-
 	if (reset) {
-		scssc_area->summary_indicator_addr = 0;
-		scssc_area->subchannel_indicator_addr = 0;
+		summary_indicator_addr = 0;
+		subchannel_indicator_addr = 0;
 	} else {
-		scssc_area->summary_indicator_addr = virt_to_phys(tiqdio_alsi);
-		scssc_area->subchannel_indicator_addr =
-			virt_to_phys(irq_ptr->dsci);
+		summary_indicator_addr = virt_to_phys(tiqdio_airq.lsi_ptr);
+		subchannel_indicator_addr = virt_to_phys(irq_ptr->dsci);
 	}
 
-	scssc_area->request = (struct chsc_header) {
-		.length = 0x0fe0,
-		.code	= 0x0021,
-	};
-	scssc_area->operation_code = 0;
-	scssc_area->ks = PAGE_DEFAULT_KEY >> 4;
-	scssc_area->kc = PAGE_DEFAULT_KEY >> 4;
-	scssc_area->isc = QDIO_AIRQ_ISC;
-	scssc_area->schid = irq_ptr->schid;
-
-	/* enable the time delay disablement facility */
-	if (css_general_characteristics.aif_tdd)
-		scssc_area->word_with_d_bit = 0x10000000;
-
-	rc = chsc(scssc_area);
-	if (rc)
-		return -EIO;
-
-	rc = chsc_error_from_response(scssc_area->response.code);
+	rc = chsc_sadc(irq_ptr->schid, scssc, summary_indicator_addr,
+		       subchannel_indicator_addr);
 	if (rc) {
 		DBF_ERROR("%4x SSI r:%4x", irq_ptr->schid.sch_no,
-			  scssc_area->response.code);
-		DBF_ERROR_HEX(&scssc_area->response, sizeof(void *));
-		return rc;
+			  scssc->response.code);
+		goto out;
 	}
 
 	DBF_EVENT("setscind");
-	DBF_HEX(&scssc_area->summary_indicator_addr, sizeof(unsigned long));
-	DBF_HEX(&scssc_area->subchannel_indicator_addr,	sizeof(unsigned long));
-	return 0;
+	DBF_HEX(&summary_indicator_addr, sizeof(summary_indicator_addr));
+	DBF_HEX(&subchannel_indicator_addr, sizeof(subchannel_indicator_addr));
+out:
+	return rc;
 }
 
 /* allocate non-shared indicators and shared indicator */
@@ -253,14 +257,12 @@ void tiqdio_free_memory(void)
 
 int __init tiqdio_register_thinints(void)
 {
-	isc_register(QDIO_AIRQ_ISC);
-	tiqdio_alsi = s390_register_adapter_interrupt(&tiqdio_thinint_handler,
-						      NULL, QDIO_AIRQ_ISC);
-	if (IS_ERR(tiqdio_alsi)) {
-		DBF_EVENT("RTI:%lx", PTR_ERR(tiqdio_alsi));
-		tiqdio_alsi = NULL;
-		isc_unregister(QDIO_AIRQ_ISC);
-		return -ENOMEM;
+	int rc;
+
+	rc = register_adapter_interrupt(&tiqdio_airq);
+	if (rc) {
+		DBF_EVENT("RTI:%x", rc);
+		return rc;
 	}
 	return 0;
 }
@@ -269,12 +271,6 @@ int qdio_establish_thinint(struct qdio_irq *irq_ptr)
 {
 	if (!is_thinint_irq(irq_ptr))
 		return 0;
-
-	/* Check for aif time delay disablement. If installed,
-	 * omit SVS even under LPAR
-	 */
-	if (css_general_characteristics.aif_tdd)
-		css_qdio_omit_svs = 1;
 	return set_subchannel_ind(irq_ptr, 0);
 }
 
@@ -292,16 +288,12 @@ void qdio_shutdown_thinint(struct qdio_irq *irq_ptr)
 		return;
 
 	/* reset adapter interrupt indicators */
-	put_indicator(irq_ptr->dsci);
 	set_subchannel_ind(irq_ptr, 1);
+	put_indicator(irq_ptr->dsci);
 }
 
 void __exit tiqdio_unregister_thinints(void)
 {
 	WARN_ON(!list_empty(&tiq_list));
-
-	if (tiqdio_alsi) {
-		s390_unregister_adapter_interrupt(tiqdio_alsi, QDIO_AIRQ_ISC);
-		isc_unregister(QDIO_AIRQ_ISC);
-	}
+	unregister_adapter_interrupt(&tiqdio_airq);
 }