KVM: irq ack notification

Based on a patch from: Ben-Ami Yassour <benami@il.ibm.com>
which was based on a patch from: Amit Shah <amit.shah@qumranet.com>

Notify IRQ acking on PIC/APIC emulation. The previous patch missed two things:

- Edge triggered interrupts on IOAPIC
- PIC reset with IRR/ISR set should be equivalent to ack (LAPIC probably
needs something similar).

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
CC: Amit Shah <amit.shah@qumranet.com>
CC: Ben-Ami Yassour <benami@il.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
diff --git a/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
index c0d2287..515cd7c 100644
--- a/virt/kvm/ioapic.c
+++ b/virt/kvm/ioapic.c
@@ -39,6 +39,7 @@
 
 #include "ioapic.h"
 #include "lapic.h"
+#include "irq.h"
 
 #if 0
 #define ioapic_debug(fmt,arg...) printk(KERN_WARNING fmt,##arg)
@@ -285,26 +286,31 @@
 	}
 }
 
-static void __kvm_ioapic_update_eoi(struct kvm_ioapic *ioapic, int gsi)
+static void __kvm_ioapic_update_eoi(struct kvm_ioapic *ioapic, int gsi,
+				    int trigger_mode)
 {
 	union ioapic_redir_entry *ent;
 
 	ent = &ioapic->redirtbl[gsi];
-	ASSERT(ent->fields.trig_mode == IOAPIC_LEVEL_TRIG);
 
-	ent->fields.remote_irr = 0;
-	if (!ent->fields.mask && (ioapic->irr & (1 << gsi)))
-		ioapic_service(ioapic, gsi);
+	kvm_notify_acked_irq(ioapic->kvm, gsi);
+
+	if (trigger_mode == IOAPIC_LEVEL_TRIG) {
+		ASSERT(ent->fields.trig_mode == IOAPIC_LEVEL_TRIG);
+		ent->fields.remote_irr = 0;
+		if (!ent->fields.mask && (ioapic->irr & (1 << gsi)))
+			ioapic_service(ioapic, gsi);
+	}
 }
 
-void kvm_ioapic_update_eoi(struct kvm *kvm, int vector)
+void kvm_ioapic_update_eoi(struct kvm *kvm, int vector, int trigger_mode)
 {
 	struct kvm_ioapic *ioapic = kvm->arch.vioapic;
 	int i;
 
 	for (i = 0; i < IOAPIC_NUM_PINS; i++)
 		if (ioapic->redirtbl[i].fields.vector == vector)
-			__kvm_ioapic_update_eoi(ioapic, i);
+			__kvm_ioapic_update_eoi(ioapic, i, trigger_mode);
 }
 
 static int ioapic_in_range(struct kvm_io_device *this, gpa_t addr,