+/* The function implicit hold kvm->lock mutex due to cancel_work_sync() */
+static void deassign_host_irq(struct kvm *kvm,
+ struct kvm_assigned_dev_kernel *assigned_dev)
+{
+ /*
+ * In kvm_free_device_irq, cancel_work_sync return true if:
+ * 1. work is scheduled, and then cancelled.
+ * 2. work callback is executed.
+ *
+ * The first one ensured that the irq is disabled and no more events
+ * would happen. But for the second one, the irq may be enabled (e.g.
+ * for MSI). So we disable irq here to prevent further events.
+ *
+ * Notice this maybe result in nested disable if the interrupt type is
+ * INTx, but it's OK for we are going to free it.
+ *
+ * If this function is a part of VM destroy, please ensure that till
+ * now, the kvm state is still legal for probably we also have to wait
+ * interrupt_work done.
+ */
+ if (assigned_dev->irq_requested_type & KVM_DEV_IRQ_HOST_MSIX) {
+ int i;
+ for (i = 0; i < assigned_dev->entries_nr; i++)
+ disable_irq_nosync(assigned_dev->
+ host_msix_entries[i].vector);
+
+ cancel_work_sync(&assigned_dev->interrupt_work);
+
+ for (i = 0; i < assigned_dev->entries_nr; i++)
+ free_irq(assigned_dev->host_msix_entries[i].vector,
+ (void *)assigned_dev);
+
+ assigned_dev->entries_nr = 0;
+ kfree(assigned_dev->host_msix_entries);
+ kfree(assigned_dev->guest_msix_entries);
+ pci_disable_msix(assigned_dev->dev);
+ } else {
+ /* Deal with MSI and INTx */
+ disable_irq_nosync(assigned_dev->host_irq);
+ cancel_work_sync(&assigned_dev->interrupt_work);
+
+ free_irq(assigned_dev->host_irq, (void *)assigned_dev);
+
+ if (assigned_dev->irq_requested_type & KVM_DEV_IRQ_HOST_MSI)
+ pci_disable_msi(assigned_dev->dev);
+ }
+
+ assigned_dev->irq_requested_type &= ~(KVM_DEV_IRQ_HOST_MASK);
+}
+
+static int kvm_deassign_irq(struct kvm *kvm,
+ struct kvm_assigned_dev_kernel *assigned_dev,
+ unsigned long irq_requested_type)
+{
+ unsigned long guest_irq_type, host_irq_type;
+
+ if (!irqchip_in_kernel(kvm))
+ return -EINVAL;
+ /* no irq assignment to deassign */
+ if (!assigned_dev->irq_requested_type)
+ return -ENXIO;
+
+ host_irq_type = irq_requested_type & KVM_DEV_IRQ_HOST_MASK;
+ guest_irq_type = irq_requested_type & KVM_DEV_IRQ_GUEST_MASK;
+
+ if (host_irq_type)
+ deassign_host_irq(kvm, assigned_dev);
+ if (guest_irq_type)
+ deassign_guest_irq(kvm, assigned_dev);
+
+ return 0;
+}
+
+static void kvm_free_assigned_irq(struct kvm *kvm,
+ struct kvm_assigned_dev_kernel *assigned_dev)
+{
+ kvm_deassign_irq(kvm, assigned_dev, assigned_dev->irq_requested_type);
+}
+
+static void kvm_free_assigned_device(struct kvm *kvm,
+ struct kvm_assigned_dev_kernel
+ *assigned_dev)
+{
+ kvm_free_assigned_irq(kvm, assigned_dev);