KVM: Report IRQ injection status for MSI delivered interrupts

Return number of CPUs interrupt was successfully injected into or -1 if
none.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 8 insertions, 5 deletions

diff --git a/virt/kvm/irq_comm.c b/virt/kvm/irq_comm.c
index be8aba791554..c516d618d389 100644
--- a/virt/kvm/irq_comm.c
+++ b/virt/kvm/irq_comm.c
@@ -48,7 +48,7 @@ static int kvm_set_ioapic_irq(struct kvm_kernel_irq_routing_entry *e,
 static int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
                        struct kvm *kvm, int level)
 {
-        int vcpu_id;
+        int vcpu_id, r = -1;
         struct kvm_vcpu *vcpu;
         struct kvm_ioapic *ioapic = ioapic_irqchip(kvm);
         int dest_id = (e->msi.address_lo & MSI_ADDR_DEST_ID_MASK)
@@ -73,7 +73,7 @@ static int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
                 vcpu = kvm_get_lowest_prio_vcpu(ioapic->kvm, vector,
                                 deliver_bitmask);
                 if (vcpu != NULL)
-                        kvm_apic_set_irq(vcpu, vector, trig_mode);
+                        r = kvm_apic_set_irq(vcpu, vector, trig_mode);
                 else
                         printk(KERN_INFO "kvm: null lowest priority vcpu!\n");
                 break;
@@ -83,14 +83,17 @@ static int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
                                 continue;
                         deliver_bitmask &= ~(1 << vcpu_id);
                         vcpu = ioapic->kvm->vcpus[vcpu_id];
-                        if (vcpu)
-                                kvm_apic_set_irq(vcpu, vector, trig_mode);
+                        if (vcpu) {
+                                if (r < 0)
+                                        r = 0;
+                                r += kvm_apic_set_irq(vcpu, vector, trig_mode);
+                        }
                 }
                 break;
         default:
                 break;
         }
-        return 1;
+        return r;
 }
 
 /* This should be called with the kvm->lock mutex held