lxc: Make activeUsbHostdevs use locks

The activeUsbHostdevs item in LXCDriver are lockable, but the lock has
to be called explicitly. Call the virObject(Un)Lock() in order to
achieve mutual exclusion once lxcDriverLock is removed.

src/lxc/lxc_driver.c

@@ -4167,7 +4167,9 @@ lxcDomainDetachDeviceHostdevUSBLive(virLXCDriverPtr driver,
         VIR_WARN("cannot deny device %s for domain %s",
                  dst, vm->def->name);
 
+    virObjectLock(driver->activeUsbHostdevs);
     virUSBDeviceListDel(driver->activeUsbHostdevs, usb);
+    virObjectUnlock(driver->activeUsbHostdevs);
 
     virDomainHostdevRemove(vm->def, idx);
     virDomainHostdevDefFree(def);

src/lxc/lxc_hostdev.c

@@ -62,10 +62,13 @@ virLXCUpdateActiveUsbHostdevs(virLXCDriverPtr driver,
 
         virUSBDeviceSetUsedBy(usb, def->name);
 
+        virObjectLock(driver->activeUsbHostdevs);
         if (virUSBDeviceListAdd(driver->activeUsbHostdevs, usb) < 0) {
+            virObjectUnlock(driver->activeUsbHostdevs);
             virUSBDeviceFree(usb);
             return -1;
         }
+        virObjectUnlock(driver->activeUsbHostdevs);
     }
 
     return 0;
@@ -83,6 +86,7 @@ virLXCPrepareHostdevUSBDevices(virLXCDriverPtr driver,
 
     count = virUSBDeviceListCount(list);
 
+    virObjectLock(driver->activeUsbHostdevs);
     for (i = 0; i < count; i++) {
         virUSBDevicePtr usb = virUSBDeviceListGet(list, i);
         if ((tmp = virUSBDeviceListFind(driver->activeUsbHostdevs, usb))) {
@@ -110,6 +114,7 @@ virLXCPrepareHostdevUSBDevices(virLXCDriverPtr driver,
         if (virUSBDeviceListAdd(driver->activeUsbHostdevs, usb) < 0)
             goto error;
     }
+    virObjectUnlock(driver->activeUsbHostdevs);
     return 0;
 
 error:
@@ -117,6 +122,7 @@ error:
         tmp = virUSBDeviceListGet(list, i);
         virUSBDeviceListSteal(driver->activeUsbHostdevs, tmp);
     }
+    virObjectUnlock(driver->activeUsbHostdevs);
     return -1;
 }
 
@@ -341,6 +347,7 @@ virLXCDomainReAttachHostUsbDevices(virLXCDriverPtr driver,
 {
     size_t i;
 
+    virObjectLock(driver->activeUsbHostdevs);
     for (i = 0; i < nhostdevs; i++) {
         virDomainHostdevDefPtr hostdev = hostdevs[i];
         virUSBDevicePtr usb, tmp;
@@ -392,6 +399,7 @@ virLXCDomainReAttachHostUsbDevices(virLXCDriverPtr driver,
             virUSBDeviceListDel(driver->activeUsbHostdevs, tmp);
         }
     }
+    virObjectUnlock(driver->activeUsbHostdevs);
 }
 
 void virLXCDomainReAttachHostDevices(virLXCDriverPtr driver,