qemu: Implement random number generator cold (un)plug

Add support for using the attach/detach device APIs on the inactive
configuration to add RNG devices.

src/libvirt_private.syms

@@ -380,6 +380,7 @@ virDomainPMSuspendedReasonTypeToString;
 virDomainRedirdevBusTypeFromString;
 virDomainRedirdevBusTypeToString;
 virDomainRNGBackendTypeToString;
+virDomainRNGDefFree;
 virDomainRNGFind;
 virDomainRNGInsert;
 virDomainRNGModelTypeToString;

src/qemu/qemu_driver.c

@@ -7427,6 +7427,23 @@ qemuDomainAttachDeviceConfig(virQEMUCapsPtr qemuCaps,
         dev->data.fs = NULL;
         break;
 
+    case VIR_DOMAIN_DEVICE_RNG:
+        if (dev->data.rng->info.type != VIR_DOMAIN_DEVICE_ADDRESS_TYPE_NONE &&
+            virDomainDefHasDeviceAddress(vmdef, &dev->data.rng->info)) {
+            virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+                           _("a device with the same address already exists "));
+            return -1;
+        }
+
+        if (virDomainRNGInsert(vmdef, dev->data.rng, false) < 0)
+            return -1;
+
+        if (qemuDomainAssignAddresses(vmdef, qemuCaps, NULL) < 0)
+            return -1;
+
+        dev->data.rng = NULL;
+        break;
+
     case VIR_DOMAIN_DEVICE_INPUT:
     case VIR_DOMAIN_DEVICE_SOUND:
     case VIR_DOMAIN_DEVICE_VIDEO:
@@ -7436,7 +7453,6 @@ qemuDomainAttachDeviceConfig(virQEMUCapsPtr qemuCaps,
     case VIR_DOMAIN_DEVICE_SMARTCARD:
     case VIR_DOMAIN_DEVICE_MEMBALLOON:
     case VIR_DOMAIN_DEVICE_NVRAM:
-    case VIR_DOMAIN_DEVICE_RNG:
     case VIR_DOMAIN_DEVICE_SHMEM:
     case VIR_DOMAIN_DEVICE_REDIRDEV:
     case VIR_DOMAIN_DEVICE_NONE:
@@ -7543,6 +7559,16 @@ qemuDomainDetachDeviceConfig(virDomainDefPtr vmdef,
         virDomainFSDefFree(fs);
         break;
 
+    case VIR_DOMAIN_DEVICE_RNG:
+        if ((idx = virDomainRNGFind(vmdef, dev->data.rng)) < 0) {
+            virReportError(VIR_ERR_OPERATION_FAILED, "%s",
+                           _("no matching RNG device was found"));
+            return -1;
+        }
+
+        virDomainRNGDefFree(virDomainRNGRemove(vmdef, idx));
+        break;
+
     case VIR_DOMAIN_DEVICE_INPUT:
     case VIR_DOMAIN_DEVICE_SOUND:
     case VIR_DOMAIN_DEVICE_VIDEO:
@@ -7552,7 +7578,6 @@ qemuDomainDetachDeviceConfig(virDomainDefPtr vmdef,
     case VIR_DOMAIN_DEVICE_SMARTCARD:
     case VIR_DOMAIN_DEVICE_MEMBALLOON:
     case VIR_DOMAIN_DEVICE_NVRAM:
-    case VIR_DOMAIN_DEVICE_RNG:
     case VIR_DOMAIN_DEVICE_SHMEM:
     case VIR_DOMAIN_DEVICE_REDIRDEV:
     case VIR_DOMAIN_DEVICE_NONE: