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/virt/kvm/ioapic.c b/virt/kvm/ioapic.c
index 1c986ac..c3b99de 100644
--- a/virt/kvm/ioapic.c
+++ b/virt/kvm/ioapic.c
@@ -83,19 +83,22 @@
return result;
}
-static void ioapic_service(struct kvm_ioapic *ioapic, unsigned int idx)
+static int ioapic_service(struct kvm_ioapic *ioapic, unsigned int idx)
{
union ioapic_redir_entry *pent;
+ int injected = -1;
pent = &ioapic->redirtbl[idx];
if (!pent->fields.mask) {
- int injected = ioapic_deliver(ioapic, idx);
+ injected = ioapic_deliver(ioapic, idx);
if (injected && pent->fields.trig_mode == IOAPIC_LEVEL_TRIG)
pent->fields.remote_irr = 1;
}
if (!pent->fields.trig_mode)
ioapic->irr &= ~(1 << idx);
+
+ return injected;
}
static void ioapic_write_indirect(struct kvm_ioapic *ioapic, u32 val)
@@ -207,7 +210,7 @@
u8 trig_mode = ioapic->redirtbl[irq].fields.trig_mode;
u32 deliver_bitmask;
struct kvm_vcpu *vcpu;
- int vcpu_id, r = 0;
+ int vcpu_id, r = -1;
ioapic_debug("dest=%x dest_mode=%x delivery_mode=%x "
"vector=%x trig_mode=%x\n",
@@ -247,7 +250,9 @@
deliver_bitmask &= ~(1 << vcpu_id);
vcpu = ioapic->kvm->vcpus[vcpu_id];
if (vcpu) {
- r = ioapic_inj_irq(ioapic, vcpu, vector,
+ if (r < 0)
+ r = 0;
+ r += ioapic_inj_irq(ioapic, vcpu, vector,
trig_mode, delivery_mode);
}
}
@@ -258,8 +263,10 @@
continue;
deliver_bitmask &= ~(1 << vcpu_id);
vcpu = ioapic->kvm->vcpus[vcpu_id];
- if (vcpu)
+ if (vcpu) {
ioapic_inj_nmi(vcpu);
+ r = 1;
+ }
else
ioapic_debug("NMI to vcpu %d failed\n",
vcpu->vcpu_id);
@@ -273,11 +280,12 @@
return r;
}
-void kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int level)
+int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int level)
{
u32 old_irr = ioapic->irr;
u32 mask = 1 << irq;
union ioapic_redir_entry entry;
+ int ret = 1;
if (irq >= 0 && irq < IOAPIC_NUM_PINS) {
entry = ioapic->redirtbl[irq];
@@ -288,9 +296,10 @@
ioapic->irr |= mask;
if ((!entry.fields.trig_mode && old_irr != ioapic->irr)
|| !entry.fields.remote_irr)
- ioapic_service(ioapic, irq);
+ ret = ioapic_service(ioapic, irq);
}
}
+ return ret;
}
static void __kvm_ioapic_update_eoi(struct kvm_ioapic *ioapic, int pin,
diff --git a/virt/kvm/ioapic.h b/virt/kvm/ioapic.h
index 49c9581..a34bd5e 100644
--- a/virt/kvm/ioapic.h
+++ b/virt/kvm/ioapic.h
@@ -83,7 +83,7 @@
unsigned long bitmap);
void kvm_ioapic_update_eoi(struct kvm *kvm, int vector, int trigger_mode);
int kvm_ioapic_init(struct kvm *kvm);
-void kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int level);
+int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int level);
void kvm_ioapic_reset(struct kvm_ioapic *ioapic);
u32 kvm_ioapic_get_delivery_bitmask(struct kvm_ioapic *ioapic, u8 dest,
u8 dest_mode);
diff --git a/virt/kvm/irq_comm.c b/virt/kvm/irq_comm.c
index 6bc7439..be8aba7 100644
--- a/virt/kvm/irq_comm.c
+++ b/virt/kvm/irq_comm.c
@@ -29,22 +29,24 @@
#include "ioapic.h"
-static void kvm_set_pic_irq(struct kvm_kernel_irq_routing_entry *e,
- struct kvm *kvm, int level)
+static int kvm_set_pic_irq(struct kvm_kernel_irq_routing_entry *e,
+ struct kvm *kvm, int level)
{
#ifdef CONFIG_X86
- kvm_pic_set_irq(pic_irqchip(kvm), e->irqchip.pin, level);
+ return kvm_pic_set_irq(pic_irqchip(kvm), e->irqchip.pin, level);
+#else
+ return -1;
#endif
}
-static void kvm_set_ioapic_irq(struct kvm_kernel_irq_routing_entry *e,
- struct kvm *kvm, int level)
+static int kvm_set_ioapic_irq(struct kvm_kernel_irq_routing_entry *e,
+ struct kvm *kvm, int level)
{
- kvm_ioapic_set_irq(kvm->arch.vioapic, e->irqchip.pin, level);
+ return kvm_ioapic_set_irq(kvm->arch.vioapic, e->irqchip.pin, level);
}
-static void kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
- struct kvm *kvm, int level)
+static int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
+ struct kvm *kvm, int level)
{
int vcpu_id;
struct kvm_vcpu *vcpu;
@@ -88,13 +90,20 @@
default:
break;
}
+ return 1;
}
-/* This should be called with the kvm->lock mutex held */
-void kvm_set_irq(struct kvm *kvm, int irq_source_id, int irq, int level)
+/* This should be called with the kvm->lock mutex held
+ * Return value:
+ * < 0 Interrupt was ignored (masked or not delivered for other reasons)
+ * = 0 Interrupt was coalesced (previous irq is still pending)
+ * > 0 Number of CPUs interrupt was delivered to
+ */
+int kvm_set_irq(struct kvm *kvm, int irq_source_id, int irq, int level)
{
struct kvm_kernel_irq_routing_entry *e;
unsigned long *irq_state, sig_level;
+ int ret = -1;
if (irq < KVM_IOAPIC_NUM_PINS) {
irq_state = (unsigned long *)&kvm->arch.irq_states[irq];
@@ -113,8 +122,14 @@
* writes to the unused one.
*/
list_for_each_entry(e, &kvm->irq_routing, link)
- if (e->gsi == irq)
- e->set(e, kvm, sig_level);
+ if (e->gsi == irq) {
+ int r = e->set(e, kvm, sig_level);
+ if (r < 0)
+ continue;
+
+ ret = r + ((ret < 0) ? 0 : ret);
+ }
+ return ret;
}
void kvm_notify_acked_irq(struct kvm *kvm, unsigned irqchip, unsigned pin)
@@ -232,7 +247,7 @@
e->set = kvm_set_pic_irq;
break;
case KVM_IRQCHIP_PIC_SLAVE:
- e->set = kvm_set_pic_irq;
+ e->set = kvm_set_pic_irq;
delta = 8;
break;
case KVM_IRQCHIP_IOAPIC: