qemu: hot-unplug of watchdog

https://bugzilla.redhat.com/show_bug.cgi?id=1447169

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>

src/qemu/qemu_driver.c

@@ -7747,12 +7747,14 @@ qemuDomainDetachDeviceLive(virDomainObjPtr vm,
     case VIR_DOMAIN_DEVICE_SHMEM:
         ret = qemuDomainDetachShmemDevice(driver, vm, dev->data.shmem);
         break;
+    case VIR_DOMAIN_DEVICE_WATCHDOG:
+        ret = qemuDomainDetachWatchdog(driver, vm, dev->data.watchdog);
+        break;
 
     case VIR_DOMAIN_DEVICE_FS:
     case VIR_DOMAIN_DEVICE_INPUT:
     case VIR_DOMAIN_DEVICE_SOUND:
     case VIR_DOMAIN_DEVICE_VIDEO:
-    case VIR_DOMAIN_DEVICE_WATCHDOG:
     case VIR_DOMAIN_DEVICE_GRAPHICS:
     case VIR_DOMAIN_DEVICE_HUB:
     case VIR_DOMAIN_DEVICE_SMARTCARD:

src/qemu/qemu_hotplug.c

@@ -4412,6 +4412,25 @@ qemuDomainRemoveShmemDevice(virQEMUDriverPtr driver,
 }
 
 
+static int
+qemuDomainRemoveWatchdog(virQEMUDriverPtr driver,
+                         virDomainObjPtr vm,
+                         virDomainWatchdogDefPtr watchdog)
+{
+    virObjectEventPtr event = NULL;
+
+    VIR_DEBUG("Removing watchdog %s from domain %p %s",
+              watchdog->info.alias, vm, vm->def->name);
+
+    event = virDomainEventDeviceRemovedNewFromObj(vm, watchdog->info.alias);
+    qemuDomainEventQueue(driver, event);
+    qemuDomainReleaseDeviceAddress(vm, &watchdog->info, NULL);
+    virDomainWatchdogDefFree(vm->def->watchdog);
+    vm->def->watchdog = NULL;
+    return 0;
+}
+
+
 int
 qemuDomainRemoveDevice(virQEMUDriverPtr driver,
                        virDomainObjPtr vm,
@@ -5128,6 +5147,54 @@ qemuDomainDetachShmemDevice(virQEMUDriverPtr driver,
 }
 
 
+int
+qemuDomainDetachWatchdog(virQEMUDriverPtr driver,
+                         virDomainObjPtr vm,
+                         virDomainWatchdogDefPtr dev)
+{
+    int ret = -1;
+    virDomainWatchdogDefPtr watchdog = vm->def->watchdog;
+    qemuDomainObjPrivatePtr priv = vm->privateData;
+
+    /* While domains can have up to one watchdog, the one supplied by the user
+     * doesn't necessarily match the one domain has. Refuse to detach in such
+     * case. */
+    if (!(watchdog &&
+          watchdog->model == dev->model &&
+          watchdog->action == dev->action &&
+          virDomainDeviceInfoAddressIsEqual(&dev->info, &watchdog->info))) {
+        virReportError(VIR_ERR_OPERATION_INVALID, "%s",
+                       _("watchdog device not present in domain configuration"));
+        return -1;
+    }
+
+    if (watchdog->model != VIR_DOMAIN_WATCHDOG_MODEL_I6300ESB) {
+        virReportError(VIR_ERR_OPERATION_UNSUPPORTED,
+                       _("hot unplug of watchdog of model %s is not supported"),
+                       virDomainWatchdogModelTypeToString(watchdog->model));
+        return -1;
+    }
+
+    qemuDomainMarkDeviceForRemoval(vm, &watchdog->info);
+    qemuDomainObjEnterMonitor(driver, vm);
+
+    ret = qemuMonitorDelDevice(priv->mon, watchdog->info.alias);
+
+    if (qemuDomainObjExitMonitor(driver, vm) < 0)
+        ret = -1;
+
+    if (ret == 0) {
+        if ((ret = qemuDomainWaitForDeviceRemoval(vm)) == 1) {
+            qemuDomainReleaseDeviceAddress(vm, &watchdog->info, NULL);
+            ret = qemuDomainRemoveWatchdog(driver, vm, watchdog);
+        }
+    }
+    qemuDomainResetDeviceRemoval(vm);
+
+    return ret;
+}
+
+
 int
 qemuDomainDetachNetDevice(virQEMUDriverPtr driver,
                           virDomainObjPtr vm,

src/qemu/qemu_hotplug.h

@@ -122,6 +122,9 @@ int qemuDomainDetachHostDevice(virQEMUDriverPtr driver,
 int qemuDomainDetachShmemDevice(virQEMUDriverPtr driver,
                                 virDomainObjPtr vm,
                                 virDomainShmemDefPtr dev);
+int qemuDomainDetachWatchdog(virQEMUDriverPtr driver,
+                             virDomainObjPtr vm,
+                             virDomainWatchdogDefPtr watchdog);
 int qemuDomainAttachLease(virQEMUDriverPtr driver,
                           virDomainObjPtr vm,
                           virDomainLeaseDefPtr lease);

tests/qemuhotplugtest.c

@@ -155,6 +155,9 @@ testQemuHotplugDetach(virDomainObjPtr vm,
     case VIR_DOMAIN_DEVICE_SHMEM:
         ret = qemuDomainDetachShmemDevice(&driver, vm, dev->data.shmem);
         break;
+    case VIR_DOMAIN_DEVICE_WATCHDOG:
+        ret = qemuDomainDetachWatchdog(&driver, vm, dev->data.watchdog);
+        break;
     default:
         VIR_TEST_VERBOSE("device type '%s' cannot be detached\n",
                 virDomainDeviceTypeToString(dev->type));
@@ -818,9 +821,11 @@ mymain(void)
                    "human-monitor-command", HMP("OK\\r\\n"),
                    "device_add", QMP_OK);
 
-    DO_TEST_ATTACH("base-live", "watchdog", false, false,
+    DO_TEST_ATTACH("base-live", "watchdog", false, true,
                    "watchdog-set-action", QMP_OK,
                    "device_add", QMP_OK);
+    DO_TEST_DETACH("base-live", "watchdog-full", false, false,
+                   "device_del", QMP_OK);
 
 #define DO_TEST_CPU_GROUP(prefix, vcpus, modernhp, expectfail)                 \
     do {                                                                       \

tests/qemuhotplugtestdevices/qemuhotplug-watchdog-full.xml

@@ -0,0 +1,4 @@
+<watchdog model='i6300esb' action='poweroff'>
+  <alias name='watchdog0'/>
+  <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/>
+</watchdog>