KVM: Report IRQ injection status to userspace.
IRQ injection status is either -1 (if there was no CPU found
that should except the interrupt because IRQ was masked or
ioapic was misconfigured or ...) or >= 0 in that case the
number indicates to how many CPUs interrupt was injected.
If the value is 0 it means that the interrupt was coalesced
and probably should be reinjected.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c
index 9316037..b4e662e 100644
--- a/arch/x86/kvm/i8259.c
+++ b/arch/x86/kvm/i8259.c
@@ -77,12 +77,13 @@
/*
* set irq level. If an edge is detected, then the IRR is set to 1
*/
-static inline void pic_set_irq1(struct kvm_kpic_state *s, int irq, int level)
+static inline int pic_set_irq1(struct kvm_kpic_state *s, int irq, int level)
{
- int mask;
+ int mask, ret = 1;
mask = 1 << irq;
if (s->elcr & mask) /* level triggered */
if (level) {
+ ret = !(s->irr & mask);
s->irr |= mask;
s->last_irr |= mask;
} else {
@@ -91,11 +92,15 @@
}
else /* edge triggered */
if (level) {
- if ((s->last_irr & mask) == 0)
+ if ((s->last_irr & mask) == 0) {
+ ret = !(s->irr & mask);
s->irr |= mask;
+ }
s->last_irr |= mask;
} else
s->last_irr &= ~mask;
+
+ return (s->imr & mask) ? -1 : ret;
}
/*
@@ -172,16 +177,19 @@
pic_unlock(s);
}
-void kvm_pic_set_irq(void *opaque, int irq, int level)
+int kvm_pic_set_irq(void *opaque, int irq, int level)
{
struct kvm_pic *s = opaque;
+ int ret = -1;
pic_lock(s);
if (irq >= 0 && irq < PIC_NUM_PINS) {
- pic_set_irq1(&s->pics[irq >> 3], irq & 7, level);
+ ret = pic_set_irq1(&s->pics[irq >> 3], irq & 7, level);
pic_update_irq(s);
}
pic_unlock(s);
+
+ return ret;
}
/*