qemu: Add and use qemuProcessEventFree for freeing qemuProcessEvents

Add and use qemuProcessEventFree for freeing qemuProcessEvents. This
is less error-prone as the compiler can help us make sure that for
every new enumeration value of qemuProcessEventType the
qemuProcessEventFree function has to be adapted.

All process*Event functions are *only* called by
qemuProcessHandleEvent and this function does the freeing by itself
with qemuProcessEventFree. This means that an explicit freeing of
processEvent->data is no longer required in each process*Event
handler.

The effectiveness of this change is also demonstrated by the fact that
it fixes a memory leak of the panic info data in
qemuProcessHandleGuestPanic.

Reported-by: Wang Dong <dongdwdw@linux.vnet.ibm.com>
Signed-off-by: Bjoern Walk <bwalk@linux.vnet.ibm.com>
Signed-off-by: Marc Hartmayer <mhartmay@linux.vnet.ibm.com>
Reviewed-by: Boris Fiuczynski <fiuczy@linux.vnet.ibm.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>

src/qemu/qemu_domain.c

@@ -11384,3 +11384,28 @@ qemuDomainPrepareDiskSource(virConnectPtr conn,
 
     return 0;
 }
+
+
+void
+qemuProcessEventFree(struct qemuProcessEvent *event)
+{
+    if (!event)
+        return;
+
+    switch (event->eventType) {
+    case QEMU_PROCESS_EVENT_GUESTPANIC:
+        qemuMonitorEventPanicInfoFree(event->data);
+        break;
+    case QEMU_PROCESS_EVENT_WATCHDOG:
+    case QEMU_PROCESS_EVENT_DEVICE_DELETED:
+    case QEMU_PROCESS_EVENT_NIC_RX_FILTER_CHANGED:
+    case QEMU_PROCESS_EVENT_SERIAL_CHANGED:
+    case QEMU_PROCESS_EVENT_BLOCK_JOB:
+    case QEMU_PROCESS_EVENT_MONITOR_EOF:
+        VIR_FREE(event->data);
+        break;
+    case QEMU_PROCESS_EVENT_LAST:
+        break;
+    }
+    VIR_FREE(event);
+}

src/qemu/qemu_domain.h

@@ -445,6 +445,8 @@ struct qemuProcessEvent {
     void *data;
 };
 
+void qemuProcessEventFree(struct qemuProcessEvent *event);
+
 typedef struct _qemuDomainLogContext qemuDomainLogContext;
 typedef qemuDomainLogContext *qemuDomainLogContextPtr;
 

src/qemu/qemu_driver.c

@@ -4183,8 +4183,8 @@ processWatchdogEvent(virQEMUDriverPtr driver,
     qemuDomainObjEndAsyncJob(driver, vm);
 
  cleanup:
-    VIR_FREE(dumpfile);
     virObjectUnref(cfg);
+    VIR_FREE(dumpfile);
 }
 
 static int
@@ -4309,7 +4309,6 @@ processGuestPanicEvent(virQEMUDriverPtr driver,
         qemuDomainRemoveInactiveJob(driver, vm);
 
  cleanup:
-    qemuMonitorEventPanicInfoFree(info);
     virObjectUnref(cfg);
 }
 
@@ -4317,7 +4316,7 @@ processGuestPanicEvent(virQEMUDriverPtr driver,
 static void
 processDeviceDeletedEvent(virQEMUDriverPtr driver,
                           virDomainObjPtr vm,
-                          char *devAlias)
+                          const char *devAlias)
 {
     virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver);
     virDomainDeviceDef dev;
@@ -4351,7 +4350,6 @@ processDeviceDeletedEvent(virQEMUDriverPtr driver,
     qemuDomainObjEndJob(driver, vm);
 
  cleanup:
-    VIR_FREE(devAlias);
     virObjectUnref(cfg);
 }
 
@@ -4547,7 +4545,7 @@ syncNicRxFilterMulticast(char *ifname,
 static void
 processNicRxFilterChangedEvent(virQEMUDriverPtr driver,
                                virDomainObjPtr vm,
-                               char *devAlias)
+                               const char *devAlias)
 {
     virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver);
     qemuDomainObjPrivatePtr priv = vm->privateData;
@@ -4648,7 +4646,6 @@ processNicRxFilterChangedEvent(virQEMUDriverPtr driver,
  cleanup:
     virNetDevRxFilterFree(hostFilter);
     virNetDevRxFilterFree(guestFilter);
-    VIR_FREE(devAlias);
     virObjectUnref(cfg);
 }
 
@@ -4656,7 +4653,7 @@ processNicRxFilterChangedEvent(virQEMUDriverPtr driver,
 static void
 processSerialChangedEvent(virQEMUDriverPtr driver,
                           virDomainObjPtr vm,
-                          char *devAlias,
+                          const char *devAlias,
                           bool connected)
 {
     virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver);
@@ -4735,23 +4732,21 @@ processSerialChangedEvent(virQEMUDriverPtr driver,
     qemuDomainObjEndJob(driver, vm);
 
  cleanup:
-    VIR_FREE(devAlias);
     virObjectUnref(cfg);
-
 }
 
 
 static void
 processBlockJobEvent(virQEMUDriverPtr driver,
                      virDomainObjPtr vm,
-                     char *diskAlias,
+                     const char *diskAlias,
                      int type,
                      int status)
 {
     virDomainDiskDefPtr disk;
 
     if (qemuDomainObjBeginJob(driver, vm, QEMU_JOB_MODIFY) < 0)
-        goto cleanup;
+        return;
 
     if (!virDomainObjIsActive(vm)) {
         VIR_DEBUG("Domain is not running");
@@ -4763,8 +4758,6 @@ processBlockJobEvent(virQEMUDriverPtr driver,
 
  endjob:
     qemuDomainObjEndJob(driver, vm);
- cleanup:
-    VIR_FREE(diskAlias);
 }
 
 
@@ -4856,7 +4849,7 @@ static void qemuProcessEventHandler(void *data, void *opaque)
     }
 
     virDomainObjEndAPI(&vm);
-    VIR_FREE(processEvent);
+    qemuProcessEventFree(processEvent);
 }
 
 

src/qemu/qemu_process.c

@@ -303,7 +303,7 @@ qemuProcessHandleMonitorEOF(qemuMonitorPtr mon,
 
     if (virThreadPoolSendJob(driver->workerPool, 0, processEvent) < 0) {
         ignore_value(virObjectUnref(vm));
-        VIR_FREE(processEvent);
+        qemuProcessEventFree(processEvent);
         goto cleanup;
     }
 
@@ -917,7 +917,7 @@ qemuProcessHandleWatchdog(qemuMonitorPtr mon ATTRIBUTE_UNUSED,
             if (virThreadPoolSendJob(driver->workerPool, 0, processEvent) < 0) {
                 if (!virObjectUnref(vm))
                     vm = NULL;
-                VIR_FREE(processEvent);
+                qemuProcessEventFree(processEvent);
             }
         }
     }
@@ -1047,9 +1047,7 @@ qemuProcessHandleBlockJob(qemuMonitorPtr mon ATTRIBUTE_UNUSED,
     virObjectUnlock(vm);
     return 0;
  error:
-    if (processEvent)
+    qemuProcessEventFree(processEvent);
-        VIR_FREE(processEvent->data);
-    VIR_FREE(processEvent);
     goto cleanup;
 }
 
@@ -1355,7 +1353,7 @@ qemuProcessHandleGuestPanic(qemuMonitorPtr mon ATTRIBUTE_UNUSED,
     if (virThreadPoolSendJob(driver->workerPool, 0, processEvent) < 0) {
         if (!virObjectUnref(vm))
             vm = NULL;
-        VIR_FREE(processEvent);
+        qemuProcessEventFree(processEvent);
     }
 
  cleanup:
@@ -1403,9 +1401,7 @@ qemuProcessHandleDeviceDeleted(qemuMonitorPtr mon ATTRIBUTE_UNUSED,
     virObjectUnlock(vm);
     return 0;
  error:
-    if (processEvent)
+    qemuProcessEventFree(processEvent);
-        VIR_FREE(processEvent->data);
-    VIR_FREE(processEvent);
     goto cleanup;
 }
 
@@ -1551,9 +1547,7 @@ qemuProcessHandleNicRxFilterChanged(qemuMonitorPtr mon ATTRIBUTE_UNUSED,
     virObjectUnlock(vm);
     return 0;
  error:
-    if (processEvent)
+    qemuProcessEventFree(processEvent);
-        VIR_FREE(processEvent->data);
-    VIR_FREE(processEvent);
     goto cleanup;
 }
 
@@ -1593,9 +1587,7 @@ qemuProcessHandleSerialChanged(qemuMonitorPtr mon ATTRIBUTE_UNUSED,
     virObjectUnlock(vm);
     return 0;
  error:
-    if (processEvent)
+    qemuProcessEventFree(processEvent);
-        VIR_FREE(processEvent->data);
-    VIR_FREE(processEvent);
     goto cleanup;
 }