Allow KVM VM live migration with ROOT volume on file storage type (#2997)

* Allow KVM VM live migration with ROOT volume on file

* Allow KVM VM live migration with ROOT volume on file
- Add JUnit tests

* Address reviewers and change some variable names to ease future
implementation (developers can easily guess the name and use
autocomplete)

Author: GabrielBrascher

api/src/main/java/com/cloud/agent/api/to/VirtualMachineTO.java

@@ -28,6 +28,7 @@ public class VirtualMachineTO {
     private long id;
     private String name;
     private BootloaderType bootloader;
+    private VirtualMachine.State state;
     Type type;
     int cpus;
 
@@ -147,6 +148,14 @@ public void setBootloader(BootloaderType bootloader) {
         this.bootloader = bootloader;
     }
 
+    public VirtualMachine.State getState() {
+        return state;
+    }
+
+    public void setState(VirtualMachine.State state) {
+        this.state = state;
+    }
+
     public int getCpus() {
         return cpus;
     }

api/src/main/java/com/cloud/vm/DiskProfile.java

@@ -72,6 +72,7 @@ public DiskProfile(Volume vol, DiskOffering offering, HypervisorType hyperType)
             offering.isCustomized(),
             null);
         this.hyperType = hyperType;
+        this.provisioningType = offering.getProvisioningType();
     }
 
     public DiskProfile(DiskProfile dp) {

core/src/main/java/com/cloud/agent/api/MigrateCommand.java

@@ -19,7 +19,9 @@
 
 package com.cloud.agent.api;
 
+import java.util.ArrayList;
 import java.util.HashMap;
+import java.util.List;
 import java.util.Map;
 
 import com.cloud.agent.api.to.VirtualMachineTO;
@@ -33,6 +35,7 @@ public class MigrateCommand extends Command {
     private boolean isWindows;
     private VirtualMachineTO vmTO;
     private boolean executeInSequence = false;
+    private List<MigrateDiskInfo> migrateDiskInfoList = new ArrayList<>();
 
     protected MigrateCommand() {
     }
@@ -90,6 +93,14 @@ public boolean executeInSequence() {
         return executeInSequence;
     }
 
+    public List<MigrateDiskInfo> getMigrateDiskInfoList() {
+        return migrateDiskInfoList;
+    }
+
+    public void setMigrateDiskInfoList(List<MigrateDiskInfo> migrateDiskInfoList) {
+        this.migrateDiskInfoList = migrateDiskInfoList;
+    }
+
     public static class MigrateDiskInfo {
         public enum DiskType {
             FILE, BLOCK;
@@ -123,6 +134,7 @@ public String toString() {
         private final DriverType driverType;
         private final Source source;
         private final String sourceText;
+        private boolean isSourceDiskOnStorageFileSystem;
 
         public MigrateDiskInfo(final String serialNumber, final DiskType diskType, final DriverType driverType, final Source source, final String sourceText) {
             this.serialNumber = serialNumber;
@@ -151,5 +163,13 @@ public Source getSource() {
         public String getSourceText() {
             return sourceText;
         }
+
+        public boolean isSourceDiskOnStorageFileSystem() {
+            return isSourceDiskOnStorageFileSystem;
+        }
+
+        public void setSourceDiskOnStorageFileSystem(boolean isDiskOnFileSystemStorage) {
+            this.isSourceDiskOnStorageFileSystem = isDiskOnFileSystemStorage;
+        }
     }
 }

engine/storage/datamotion/src/main/java/org/apache/cloudstack/storage/motion/KvmNonManagedStorageDataMotionStrategy.java

@@ -0,0 +1,143 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.apache.cloudstack.storage.motion;
+
+import java.io.File;
+import java.util.Map;
+import java.util.Set;
+
+import javax.inject.Inject;
+
+import org.apache.cloudstack.engine.subsystem.api.storage.DataStore;
+import org.apache.cloudstack.engine.subsystem.api.storage.StrategyPriority;
+import org.apache.cloudstack.engine.subsystem.api.storage.TemplateDataFactory;
+import org.apache.cloudstack.engine.subsystem.api.storage.TemplateInfo;
+import org.apache.cloudstack.engine.subsystem.api.storage.VolumeInfo;
+import org.apache.cloudstack.storage.datastore.db.StoragePoolVO;
+
+import com.cloud.agent.api.Answer;
+import com.cloud.agent.api.MigrateCommand;
+import com.cloud.agent.api.MigrateCommand.MigrateDiskInfo;
+import com.cloud.agent.api.storage.CreateAnswer;
+import com.cloud.agent.api.storage.CreateCommand;
+import com.cloud.agent.api.to.VirtualMachineTO;
+import com.cloud.host.Host;
+import com.cloud.hypervisor.Hypervisor.HypervisorType;
+import com.cloud.storage.DataStoreRole;
+import com.cloud.storage.DiskOfferingVO;
+import com.cloud.storage.Storage.StoragePoolType;
+import com.cloud.storage.VolumeVO;
+import com.cloud.utils.exception.CloudRuntimeException;
+import com.cloud.vm.DiskProfile;
+
+/**
+ * Extends {@link StorageSystemDataMotionStrategy}, allowing KVM hosts to migrate VMs with the ROOT volume on a non managed local storage pool.
+ * As {@link StorageSystemDataMotionStrategy} is considering KVM, this implementation also migrates only from/to KVM hosts.
+ */
+public class KvmNonManagedStorageDataMotionStrategy extends StorageSystemDataMotionStrategy {
+
+    @Inject
+    private TemplateDataFactory templateDataFactory;
+
+    /**
+     * Uses the canHandle from the Super class {@link StorageSystemDataMotionStrategy}. If the storage pool is of file and the internalCanHandle from {@link StorageSystemDataMotionStrategy} CANT_HANDLE, returns the StrategyPriority.HYPERVISOR strategy priority. otherwise returns CANT_HANDLE.
+     * Note that the super implementation (override) is called by {@link #canHandle(Map, Host, Host)} which ensures that {@link #internalCanHandle(Map)} will be executed only if the source host is KVM.
+     */
+    @Override
+    protected StrategyPriority internalCanHandle(Map<VolumeInfo, DataStore> volumeMap) {
+        if (super.internalCanHandle(volumeMap) == StrategyPriority.CANT_HANDLE) {
+            Set<VolumeInfo> volumeInfoSet = volumeMap.keySet();
+
+            for (VolumeInfo volumeInfo : volumeInfoSet) {
+                StoragePoolVO storagePoolVO = _storagePoolDao.findById(volumeInfo.getPoolId());
+                if (storagePoolVO.getPoolType() != StoragePoolType.Filesystem && storagePoolVO.getPoolType() != StoragePoolType.NetworkFilesystem) {
+                    return StrategyPriority.CANT_HANDLE;
+                }
+            }
+            return StrategyPriority.HYPERVISOR;
+        }
+        return StrategyPriority.CANT_HANDLE;
+    }
+
+    /**
+     * Configures a {@link MigrateDiskInfo} object configured for migrating a File System volume and calls rootImageProvisioning.
+     */
+    @Override
+    protected MigrateCommand.MigrateDiskInfo configureMigrateDiskInfo(VolumeInfo srcVolumeInfo, String destPath) {
+        return new MigrateCommand.MigrateDiskInfo(srcVolumeInfo.getPath(), MigrateCommand.MigrateDiskInfo.DiskType.FILE, MigrateCommand.MigrateDiskInfo.DriverType.QCOW2,
+                MigrateCommand.MigrateDiskInfo.Source.FILE, destPath);
+    }
+
+    /**
+     * Generates the volume path by appending the Volume UUID to the Libvirt destiny images path.</br>
+     * Example: /var/lib/libvirt/images/f3d49ecc-870c-475a-89fa-fd0124420a9b
+     */
+    @Override
+    protected String generateDestPath(VirtualMachineTO vmTO, VolumeVO srcVolume, Host destHost, StoragePoolVO destStoragePool, VolumeInfo destVolumeInfo) {
+        DiskOfferingVO diskOffering = _diskOfferingDao.findById(srcVolume.getDiskOfferingId());
+        DiskProfile diskProfile = new DiskProfile(destVolumeInfo, diskOffering, HypervisorType.KVM);
+        String templateUuid = getTemplateUuid(destVolumeInfo.getTemplateId());
+        CreateCommand rootImageProvisioningCommand = new CreateCommand(diskProfile, templateUuid, destStoragePool, true);
+
+        Answer rootImageProvisioningAnswer = _agentMgr.easySend(destHost.getId(), rootImageProvisioningCommand);
+
+        if (rootImageProvisioningAnswer == null) {
+            throw new CloudRuntimeException(String.format("Migration with storage of vm [%s] failed while provisioning root image", vmTO.getName()));
+        }
+
+        if (!rootImageProvisioningAnswer.getResult()) {
+            throw new CloudRuntimeException(String.format("Unable to modify target volume on the host [host id:%s, name:%s]", destHost.getId(), destHost.getName()));
+        }
+
+        String libvirtDestImgsPath = null;
+        if (rootImageProvisioningAnswer instanceof CreateAnswer) {
+            libvirtDestImgsPath = ((CreateAnswer)rootImageProvisioningAnswer).getVolume().getName();
+        }
+        // File.getAbsolutePath is used to keep the file separator as it should be and eliminate a verification to check if exists a file separator in the last character of libvirtDestImgsPath.
+        return new File(libvirtDestImgsPath, destVolumeInfo.getUuid()).getAbsolutePath();
+    }
+
+    /**
+     * Returns the template UUID with the given id. If the template ID is null, it returns null.
+     */
+    protected String getTemplateUuid(Long templateId) {
+        if (templateId == null) {
+            return null;
+        }
+        TemplateInfo templateImage = templateDataFactory.getTemplate(templateId, DataStoreRole.Image);
+        return templateImage.getUuid();
+    }
+
+    /**
+     * Sets the volume path as the volume UUID.
+     */
+    @Override
+    protected void setVolumePath(VolumeVO volume) {
+        volume.setPath(volume.getUuid());
+    }
+
+    /**
+     * Return true if the volume should be migrated. Currently only supports migrating volumes on storage pool of the type StoragePoolType.Filesystem.
+     * This ensures that volumes on shared storage are not migrated and those on local storage pools are migrated.
+     */
+    @Override
+    protected boolean shouldMigrateVolume(StoragePoolVO sourceStoragePool, Host destHost, StoragePoolVO destStoragePool) {
+        return sourceStoragePool.getPoolType() == StoragePoolType.Filesystem;
+    }
+}