hw/xen: Implement EVTCHNOP_unmask

This finally comes with a mechanism for actually injecting events into
the guest vCPU, with all the atomic-test-and-set that's involved in
setting the bit in the shinfo, then the index in the vcpu_info, and
injecting either the lapic vector as MSI, or letting KVM inject the
bare vector.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>

1 files changed, 12 insertions, 0 deletions

diff --git a/target/i386/kvm/xen-emu.c b/target/i386/kvm/xen-emu.c
index fab7d6b..884e1c9 100644
--- a/target/i386/kvm/xen-emu.c
+++ b/target/i386/kvm/xen-emu.c
@@ -817,6 +817,18 @@ static bool kvm_xen_hcall_evtchn_op(struct kvm_xen_exit *exit, X86CPU *cpu,
         err = xen_evtchn_close_op(&close);
         break;
     }
+    case EVTCHNOP_unmask: {
+        struct evtchn_unmask unmask;
+
+        qemu_build_assert(sizeof(unmask) == 4);
+        if (kvm_copy_from_gva(cs, arg, &unmask, sizeof(unmask))) {
+            err = -EFAULT;
+            break;
+        }
+
+        err = xen_evtchn_unmask_op(&unmask);
+        break;
+    }
     default:
         return false;
     }