s390/airq: simplify adapter interrupt code

There are three users of adapter interrupts: AP, QDIO and PCI. Each
registers a single adapter interrupt with independent ISCs. Define
a "struct airq" with the interrupt handler, a pointer and a mask for
the local summary indicator and the ISC for the adapter interrupt
source. Convert the indicator array with its fixed number of adapter
interrupt sources per ISE to an array of hlists. This removes the
limitation to 32 adapter interrupts per ISC and allows for arbitrary
memory locations for the local summary indicator.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

2 files changed, 25 insertions, 17 deletions

diff --git a/arch/s390/include/asm/airq.h b/arch/s390/include/asm/airq.h
index 9819891ed7a2..4066cee0c2d2 100644
--- a/arch/s390/include/asm/airq.h
+++ b/arch/s390/include/asm/airq.h
@@ -9,9 +9,18 @@
 #ifndef _ASM_S390_AIRQ_H
 #define _ASM_S390_AIRQ_H
 
-typedef void (*adapter_int_handler_t)(void *, void *);
+struct airq_struct {
+	struct hlist_node list;		/* Handler queueing. */
+	void (*handler)(struct airq_struct *);	/* Thin-interrupt handler */
+	u8 *lsi_ptr;			/* Local-Summary-Indicator pointer */
+	u8 lsi_mask;			/* Local-Summary-Indicator mask */
+	u8 isc;				/* Interrupt-subclass */
+	u8 flags;
+};
 
-void *s390_register_adapter_interrupt(adapter_int_handler_t, void *, u8);
-void s390_unregister_adapter_interrupt(void *, u8);
+#define AIRQ_PTR_ALLOCATED	0x01
+
+int register_adapter_interrupt(struct airq_struct *airq);
+void unregister_adapter_interrupt(struct airq_struct *airq);
 
 #endif /* _ASM_S390_AIRQ_H */
diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c
index 51c3ca86bd05..e2956ad39a4f 100644
--- a/arch/s390/pci/pci.c
+++ b/arch/s390/pci/pci.c
@@ -82,8 +82,13 @@ struct intr_bucket {
 
 static struct intr_bucket *bucket;
 
-/* Adapter local summary indicator */
-static u8 *zpci_irq_si;
+/* Adapter interrupt definitions */
+static void zpci_irq_handler(struct airq_struct *airq);
+
+static struct airq_struct zpci_airq = {
+	.handler = zpci_irq_handler,
+	.isc = PCI_ISC,
+};
 
 /* I/O Map */
 static DEFINE_SPINLOCK(zpci_iomap_lock);
@@ -402,7 +407,7 @@ static struct pci_ops pci_root_ops = {
 /* store the last handled bit to implement fair scheduling of devices */
 static DEFINE_PER_CPU(unsigned long, next_sbit);
 
-static void zpci_irq_handler(void *dont, void *need)
+static void zpci_irq_handler(struct airq_struct *airq)
 {
 	unsigned long sbit, mbit, last = 0, start = __get_cpu_var(next_sbit);
 	int rescan = 0, max = aisb_max;
@@ -712,25 +717,20 @@ static int __init zpci_irq_init(void)
 		goto out_alloc;
 	}
 
-	isc_register(PCI_ISC);
-	zpci_irq_si = s390_register_adapter_interrupt(&zpci_irq_handler, NULL, PCI_ISC);
-	if (IS_ERR(zpci_irq_si)) {
-		rc = PTR_ERR(zpci_irq_si);
-		zpci_irq_si = NULL;
+	rc = register_adapter_interrupt(&zpci_airq);
+	if (rc)
 		goto out_ai;
-	}
+	/* Set summary to 1 to be called every time for the ISC. */
+	*zpci_airq.lsi_ptr = 1;
 
 	for_each_online_cpu(cpu)
 		per_cpu(next_sbit, cpu) = 0;
 
 	spin_lock_init(&bucket->lock);
-	/* set summary to 1 to be called every time for the ISC */
-	*zpci_irq_si = 1;
 	set_irq_ctrl(SIC_IRQ_MODE_SINGLE, NULL, PCI_ISC);
 	return 0;
 
 out_ai:
-	isc_unregister(PCI_ISC);
 	free_page((unsigned long) bucket->alloc);
 out_alloc:
 	free_page((unsigned long) bucket->aisb);
@@ -743,8 +743,7 @@ static void zpci_irq_exit(void)
 {
 	free_page((unsigned long) bucket->alloc);
 	free_page((unsigned long) bucket->aisb);
-	s390_unregister_adapter_interrupt(zpci_irq_si, PCI_ISC);
-	isc_unregister(PCI_ISC);
+	unregister_adapter_interrupt(&zpci_airq);
 	kfree(bucket);
 }