KVM: Add support to disable MSI for assigned device

[linux-2.6-omap-h63xx.git] / virt / kvm / kvm_main.c

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index f83ef9c7e89ba193267533c6a958df58b10c4a33..04401e17c7585e63d524fabbe371e957e917c9c2 100644 (file)
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -343,6 +343,14 @@ static int assigned_device_update_msi(struct kvm *kvm,
                adev->irq_requested_type &= ~KVM_ASSIGNED_DEV_GUEST_MSI;
                adev->guest_irq = airq->guest_irq;
                adev->ack_notifier.gsi = airq->guest_irq;
+       } else {
+               /*
+                * Guest require to disable device MSI, we disable MSI and
+                * re-enable INTx by default again. Notice it's only for
+                * non-msi2intx.
+                */
+               assigned_device_update_intx(kvm, adev, airq);
+               return 0;
        }
 
        if (adev->irq_requested_type & KVM_ASSIGNED_DEV_HOST_MSI)
@@ -379,6 +387,7 @@ static int kvm_vm_ioctl_assign_irq(struct kvm *kvm,
 {
        int r = 0;
        struct kvm_assigned_dev_kernel *match;
+       u32 current_flags = 0, changed_flags;
 
        mutex_lock(&kvm->lock);
 
@@ -416,8 +425,13 @@ static int kvm_vm_ioctl_assign_irq(struct kvm *kvm,
                }
        }
 
-       if ((!msi2intx &&
-            (assigned_irq->flags & KVM_DEV_IRQ_ASSIGN_ENABLE_MSI)) ||
+       if ((match->irq_requested_type & KVM_ASSIGNED_DEV_HOST_MSI) &&
+                (match->irq_requested_type & KVM_ASSIGNED_DEV_GUEST_MSI))
+               current_flags |= KVM_DEV_IRQ_ASSIGN_ENABLE_MSI;
+
+       changed_flags = assigned_irq->flags ^ current_flags;
+
+       if ((changed_flags & KVM_DEV_IRQ_ASSIGN_MSI_ACTION) ||
            (msi2intx && match->dev->msi_enabled)) {
 #ifdef CONFIG_X86
                r = assigned_device_update_msi(kvm, match, assigned_irq);