vfio: refactor out vfio_interrupt_setup()

Refactor the interrupt setup code out of vfio_realize() for readability.

Signed-off-by: John Levon <john.levon@nutanix.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/qemu-devel/20250409134814.478903-2-john.levon@nutanix.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>

1 files changed, 34 insertions, 21 deletions

diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index 6fa7217db8..27cc6426a5 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -2962,6 +2962,38 @@ static void vfio_unregister_req_notifier(VFIOPCIDevice *vdev)
     vdev->req_enabled = false;
 }
 
+static bool vfio_interrupt_setup(VFIOPCIDevice *vdev, Error **errp)
+{
+    PCIDevice *pdev = &vdev->pdev;
+
+    /* QEMU emulates all of MSI & MSIX */
+    if (pdev->cap_present & QEMU_PCI_CAP_MSIX) {
+        memset(vdev->emulated_config_bits + pdev->msix_cap, 0xff,
+               MSIX_CAP_LENGTH);
+    }
+
+    if (pdev->cap_present & QEMU_PCI_CAP_MSI) {
+        memset(vdev->emulated_config_bits + pdev->msi_cap, 0xff,
+               vdev->msi_cap_size);
+    }
+
+    if (vfio_pci_read_config(&vdev->pdev, PCI_INTERRUPT_PIN, 1)) {
+        vdev->intx.mmap_timer = timer_new_ms(QEMU_CLOCK_VIRTUAL,
+                                             vfio_intx_mmap_enable, vdev);
+        pci_device_set_intx_routing_notifier(&vdev->pdev,
+                                             vfio_intx_routing_notifier);
+        vdev->irqchip_change_notifier.notify = vfio_irqchip_change;
+        kvm_irqchip_add_change_notifier(&vdev->irqchip_change_notifier);
+        if (!vfio_intx_enable(vdev, errp)) {
+            timer_free(vdev->intx.mmap_timer);
+            pci_device_set_intx_routing_notifier(&vdev->pdev, NULL);
+            kvm_irqchip_remove_change_notifier(&vdev->irqchip_change_notifier);
+            return false;
+        }
+    }
+    return true;
+}
+
 static void vfio_realize(PCIDevice *pdev, Error **errp)
 {
     ERRP_GUARD();
@@ -3141,27 +3173,8 @@ static void vfio_realize(PCIDevice *pdev, Error **errp)
         vfio_bar_quirk_setup(vdev, i);
     }
 
-    /* QEMU emulates all of MSI & MSIX */
-    if (pdev->cap_present & QEMU_PCI_CAP_MSIX) {
-        memset(vdev->emulated_config_bits + pdev->msix_cap, 0xff,
-               MSIX_CAP_LENGTH);
-    }
-
-    if (pdev->cap_present & QEMU_PCI_CAP_MSI) {
-        memset(vdev->emulated_config_bits + pdev->msi_cap, 0xff,
-               vdev->msi_cap_size);
-    }
-
-    if (vfio_pci_read_config(&vdev->pdev, PCI_INTERRUPT_PIN, 1)) {
-        vdev->intx.mmap_timer = timer_new_ms(QEMU_CLOCK_VIRTUAL,
-                                                  vfio_intx_mmap_enable, vdev);
-        pci_device_set_intx_routing_notifier(&vdev->pdev,
-                                             vfio_intx_routing_notifier);
-        vdev->irqchip_change_notifier.notify = vfio_irqchip_change;
-        kvm_irqchip_add_change_notifier(&vdev->irqchip_change_notifier);
-        if (!vfio_intx_enable(vdev, errp)) {
-            goto out_deregister;
-        }
+    if (!vfio_interrupt_setup(vdev, errp)) {
+        goto out_unset_idev;
     }
 
     if (vdev->display != ON_OFF_AUTO_OFF) {