diff --git a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
index 1aefd09af6c..701ca50f997 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
+++ b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
@@ -32,6 +32,9 @@ Release 2.5.0 - UNRELEASED
 
     HDFS-6164. Remove lsr in OfflineImageViewer. (wheat9)
 
+    HDFS-6167. Relocate the non-public API classes in the hdfs.client package.
+    (szetszwo)
+
   OPTIMIZATIONS
 
   BUG FIXES 
diff --git a/hadoop-hdfs-project/hadoop-hdfs/dev-support/findbugsExcludeFile.xml b/hadoop-hdfs-project/hadoop-hdfs/dev-support/findbugsExcludeFile.xml
index 73326b9af9b..29702d4bace 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/dev-support/findbugsExcludeFile.xml
+++ b/hadoop-hdfs-project/hadoop-hdfs/dev-support/findbugsExcludeFile.xml
@@ -165,12 +165,12 @@
        <Bug pattern="DM_STRING_CTOR" />
      </Match>
     <Match>
-      <Class name="org.apache.hadoop.hdfs.client.DfsClientShmManager$EndpointShmManager" />
+      <Class name="org.apache.hadoop.hdfs.shortcircuit.DfsClientShmManager$EndpointShmManager" />
       <Method name="allocSlot" />
       <Bug pattern="UL_UNRELEASED_LOCK_EXCEPTION_PATH" />
     </Match>
     <Match>
-      <Class name="org.apache.hadoop.hdfs.client.DfsClientShmManager$EndpointShmManager" />
+      <Class name="org.apache.hadoop.hdfs.shortcircuit.DfsClientShmManager$EndpointShmManager" />
       <Method name="allocSlot" />
       <Bug pattern="UL_UNRELEASED_LOCK" />
     </Match>
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/BlockReader.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/BlockReader.java
index 26dc5b6aaf0..a5beb326788 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/BlockReader.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/BlockReader.java
@@ -22,7 +22,7 @@
 
 import org.apache.hadoop.fs.ByteBufferReadable;
 import org.apache.hadoop.fs.ReadOption;
-import org.apache.hadoop.hdfs.client.ClientMmap;
+import org.apache.hadoop.hdfs.shortcircuit.ClientMmap;
 
 /**
  * A BlockReader is responsible for reading a single block
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/BlockReaderFactory.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/BlockReaderFactory.java
index eeda2dcb325..3355404c7a7 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/BlockReaderFactory.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/BlockReaderFactory.java
@@ -25,16 +25,10 @@
 import java.net.InetSocketAddress;
 
 import org.apache.commons.lang.mutable.MutableBoolean;
-import org.apache.commons.logging.LogFactory;
 import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.conf.Configuration;
-import org.apache.hadoop.hdfs.client.ShortCircuitCache;
-import org.apache.hadoop.hdfs.client.ShortCircuitCache.ShortCircuitReplicaCreator;
-import org.apache.hadoop.hdfs.client.ShortCircuitReplica;
-import org.apache.hadoop.hdfs.client.ShortCircuitReplicaInfo;
-import org.apache.hadoop.hdfs.ShortCircuitShm.Slot;
-import org.apache.hadoop.hdfs.ShortCircuitShm.SlotId;
 import org.apache.hadoop.hdfs.net.DomainPeer;
 import org.apache.hadoop.hdfs.net.Peer;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
@@ -46,6 +40,13 @@
 import org.apache.hadoop.hdfs.security.token.block.BlockTokenIdentifier;
 import org.apache.hadoop.hdfs.security.token.block.InvalidBlockTokenException;
 import org.apache.hadoop.hdfs.server.datanode.CachingStrategy;
+import org.apache.hadoop.hdfs.shortcircuit.DomainSocketFactory;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitCache;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitCache.ShortCircuitReplicaCreator;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitReplica;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitReplicaInfo;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.Slot;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.SlotId;
 import org.apache.hadoop.io.IOUtils;
 import org.apache.hadoop.ipc.RemoteException;
 import org.apache.hadoop.net.unix.DomainSocket;
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/BlockReaderLocal.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/BlockReaderLocal.java
index ca6c041c1df..1cb0e8aaf4b 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/BlockReaderLocal.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/BlockReaderLocal.java
@@ -25,12 +25,12 @@
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.fs.ReadOption;
-import org.apache.hadoop.hdfs.client.ClientMmap;
-import org.apache.hadoop.hdfs.client.ShortCircuitReplica;
 import org.apache.hadoop.hdfs.DFSClient.Conf;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
 import org.apache.hadoop.hdfs.server.datanode.BlockMetadataHeader;
 import org.apache.hadoop.hdfs.server.datanode.CachingStrategy;
+import org.apache.hadoop.hdfs.shortcircuit.ClientMmap;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitReplica;
 import org.apache.hadoop.hdfs.util.DirectBufferPool;
 import org.apache.hadoop.util.DataChecksum;
 
@@ -274,8 +274,7 @@ private synchronized void freeChecksumBufIfExists() {
     }
   }
 
-  private synchronized int drainDataBuf(ByteBuffer buf)
-      throws IOException {
+  private synchronized int drainDataBuf(ByteBuffer buf) {
     if (dataBuf == null) return -1;
     int oldLimit = dataBuf.limit();
     int nRead = Math.min(dataBuf.remaining(), buf.remaining());
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/BlockReaderLocalLegacy.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/BlockReaderLocalLegacy.java
index 3665d802566..ddd25366e02 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/BlockReaderLocalLegacy.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/BlockReaderLocalLegacy.java
@@ -29,18 +29,17 @@
 import java.util.LinkedHashMap;
 import java.util.Map;
 
-import org.apache.hadoop.fs.ReadOption;
-import org.apache.hadoop.hdfs.client.ClientMmap;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.ReadOption;
 import org.apache.hadoop.hdfs.protocol.BlockLocalPathInfo;
 import org.apache.hadoop.hdfs.protocol.ClientDatanodeProtocol;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
-import org.apache.hadoop.hdfs.protocol.LocatedBlock;
 import org.apache.hadoop.hdfs.security.token.block.BlockTokenIdentifier;
 import org.apache.hadoop.hdfs.server.datanode.BlockMetadataHeader;
+import org.apache.hadoop.hdfs.shortcircuit.ClientMmap;
 import org.apache.hadoop.hdfs.util.DirectBufferPool;
 import org.apache.hadoop.io.IOUtils;
 import org.apache.hadoop.ipc.RPC;
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/ClientContext.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/ClientContext.java
index 7d94c7f4882..f55aff5fd3a 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/ClientContext.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/ClientContext.java
@@ -17,17 +17,17 @@
  */
 package org.apache.hadoop.hdfs;
 
-import com.google.common.annotations.VisibleForTesting;
-
 import java.util.HashMap;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
-import org.apache.hadoop.hdfs.DFSClient;
-import org.apache.hadoop.hdfs.DFSClient.Conf;
-import org.apache.hadoop.hdfs.client.ShortCircuitCache;
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hdfs.DFSClient.Conf;
+import org.apache.hadoop.hdfs.shortcircuit.DomainSocketFactory;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitCache;
+
+import com.google.common.annotations.VisibleForTesting;
 
 /**
  * ClientContext contains context information for a client.
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSClient.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSClient.java
index eccefecba2d..84b090e12dc 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSClient.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSClient.java
@@ -432,6 +432,22 @@ public Conf(Configuration conf) {
           DFS_CLIENT_DATANODE_RESTART_TIMEOUT_DEFAULT) * 1000;
     }
 
+    public boolean isUseLegacyBlockReaderLocal() {
+      return useLegacyBlockReaderLocal;
+    }
+
+    public String getDomainSocketPath() {
+      return domainSocketPath;
+    }
+
+    public boolean isShortCircuitLocalReads() {
+      return shortCircuitLocalReads;
+    }
+
+    public boolean isDomainSocketDataTraffic() {
+      return domainSocketDataTraffic;
+    }
+
     private DataChecksum.Type getChecksumType(Configuration conf) {
       final String checksum = conf.get(
           DFSConfigKeys.DFS_CHECKSUM_TYPE_KEY,
@@ -959,7 +975,7 @@ public long renewDelegationToken(Token<DelegationTokenIdentifier> token)
   private static final Map<String, Boolean> localAddrMap = Collections
       .synchronizedMap(new HashMap<String, Boolean>());
   
-  static boolean isLocalAddress(InetSocketAddress targetAddr) {
+  public static boolean isLocalAddress(InetSocketAddress targetAddr) {
     InetAddress addr = targetAddr.getAddress();
     Boolean cached = localAddrMap.get(addr.getHostAddress());
     if (cached != null) {
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSInputStream.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSInputStream.java
index 7396dedc545..756ef4b60d3 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSInputStream.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSInputStream.java
@@ -50,7 +50,6 @@
 import org.apache.hadoop.fs.HasEnhancedByteBufferAccess;
 import org.apache.hadoop.fs.ReadOption;
 import org.apache.hadoop.fs.UnresolvedLinkException;
-import org.apache.hadoop.hdfs.client.ClientMmap;
 import org.apache.hadoop.hdfs.protocol.ClientDatanodeProtocol;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
@@ -61,6 +60,7 @@
 import org.apache.hadoop.hdfs.security.token.block.InvalidBlockTokenException;
 import org.apache.hadoop.hdfs.server.datanode.CachingStrategy;
 import org.apache.hadoop.hdfs.server.datanode.ReplicaNotFoundException;
+import org.apache.hadoop.hdfs.shortcircuit.ClientMmap;
 import org.apache.hadoop.io.ByteBufferPool;
 import org.apache.hadoop.ipc.RPC;
 import org.apache.hadoop.ipc.RemoteException;
@@ -80,7 +80,7 @@ public class DFSInputStream extends FSInputStream
 implements ByteBufferReadable, CanSetDropBehind, CanSetReadahead,
     HasEnhancedByteBufferAccess {
   @VisibleForTesting
-  static boolean tcpReadsDisabledForTesting = false;
+  public static boolean tcpReadsDisabledForTesting = false;
   private final DFSClient dfsClient;
   private boolean closed = false;
   private final String src;
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSUtil.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSUtil.java
index 309ae4009da..515f5997bd2 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSUtil.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSUtil.java
@@ -1190,7 +1190,7 @@ public static ClientDatanodeProtocol createClientDatanodeProtocolProxy(
   }
   
   /** Create {@link ClientDatanodeProtocol} proxy using kerberos ticket */
-  static ClientDatanodeProtocol createClientDatanodeProtocolProxy(
+  public static ClientDatanodeProtocol createClientDatanodeProtocolProxy(
       DatanodeID datanodeid, Configuration conf, int socketTimeout,
       boolean connectToDnViaHostname) throws IOException {
     return new ClientDatanodeProtocolTranslatorPB(
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/PeerCache.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/PeerCache.java
index 47e79ba020a..fbe4e15581a 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/PeerCache.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/PeerCache.java
@@ -173,7 +173,6 @@ public synchronized Peer get(DatanodeID dnId, boolean isDomain) {
 
   /**
    * Give an unused socket to the cache.
-   * @param sock socket not used by anyone.
    */
   public synchronized void put(DatanodeID dnId, Peer peer) {
     Preconditions.checkNotNull(dnId);
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/RemoteBlockReader.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/RemoteBlockReader.java
index f37565ed8d2..25a72870c7d 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/RemoteBlockReader.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/RemoteBlockReader.java
@@ -29,11 +29,9 @@
 import org.apache.hadoop.fs.FSInputChecker;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.ReadOption;
-import org.apache.hadoop.hdfs.client.ClientMmap;
 import org.apache.hadoop.hdfs.net.Peer;
 import org.apache.hadoop.hdfs.protocol.DatanodeID;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
-import org.apache.hadoop.hdfs.protocol.LocatedBlock;
 import org.apache.hadoop.hdfs.protocol.datatransfer.DataTransferProtoUtil;
 import org.apache.hadoop.hdfs.protocol.datatransfer.PacketHeader;
 import org.apache.hadoop.hdfs.protocol.datatransfer.Sender;
@@ -43,6 +41,7 @@
 import org.apache.hadoop.hdfs.protocolPB.PBHelper;
 import org.apache.hadoop.hdfs.security.token.block.BlockTokenIdentifier;
 import org.apache.hadoop.hdfs.server.datanode.CachingStrategy;
+import org.apache.hadoop.hdfs.shortcircuit.ClientMmap;
 import org.apache.hadoop.io.IOUtils;
 import org.apache.hadoop.net.NetUtils;
 import org.apache.hadoop.security.token.Token;
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/RemoteBlockReader2.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/RemoteBlockReader2.java
index 9cb975d92b5..44d59798355 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/RemoteBlockReader2.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/RemoteBlockReader2.java
@@ -31,11 +31,9 @@
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.fs.ReadOption;
-import org.apache.hadoop.hdfs.client.ClientMmap;
 import org.apache.hadoop.hdfs.net.Peer;
 import org.apache.hadoop.hdfs.protocol.DatanodeID;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
-import org.apache.hadoop.hdfs.protocol.LocatedBlock;
 import org.apache.hadoop.hdfs.protocol.datatransfer.DataTransferProtoUtil;
 import org.apache.hadoop.hdfs.protocol.datatransfer.PacketHeader;
 import org.apache.hadoop.hdfs.protocol.datatransfer.PacketReceiver;
@@ -48,6 +46,7 @@
 import org.apache.hadoop.hdfs.security.token.block.BlockTokenIdentifier;
 import org.apache.hadoop.hdfs.security.token.block.InvalidBlockTokenException;
 import org.apache.hadoop.hdfs.server.datanode.CachingStrategy;
+import org.apache.hadoop.hdfs.shortcircuit.ClientMmap;
 import org.apache.hadoop.net.NetUtils;
 import org.apache.hadoop.security.token.Token;
 import org.apache.hadoop.util.DataChecksum;
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/net/DomainPeerServer.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/net/DomainPeerServer.java
index e7de0d7a5aa..95a138894d9 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/net/DomainPeerServer.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/net/DomainPeerServer.java
@@ -23,10 +23,8 @@
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
-import org.apache.hadoop.io.IOUtils;
-import org.apache.hadoop.hdfs.net.PeerServer;
-import org.apache.hadoop.net.unix.DomainSocket;
 import org.apache.hadoop.classification.InterfaceAudience;
+import org.apache.hadoop.net.unix.DomainSocket;
 
 @InterfaceAudience.Private
 public class DomainPeerServer implements PeerServer {
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocol/datatransfer/DataTransferProtocol.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocol/datatransfer/DataTransferProtocol.java
index be5f3d12af7..772853a85aa 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocol/datatransfer/DataTransferProtocol.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocol/datatransfer/DataTransferProtocol.java
@@ -23,11 +23,11 @@
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
-import org.apache.hadoop.hdfs.ShortCircuitShm.SlotId;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
 import org.apache.hadoop.hdfs.security.token.block.BlockTokenIdentifier;
 import org.apache.hadoop.hdfs.server.datanode.CachingStrategy;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.SlotId;
 import org.apache.hadoop.security.token.Token;
 import org.apache.hadoop.util.DataChecksum;
 
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocol/datatransfer/Receiver.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocol/datatransfer/Receiver.java
index 7c9ea17e39d..5a80f689da3 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocol/datatransfer/Receiver.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocol/datatransfer/Receiver.java
@@ -17,27 +17,27 @@
  */
 package org.apache.hadoop.hdfs.protocol.datatransfer;
 
-import static org.apache.hadoop.hdfs.protocolPB.PBHelper.vintPrefixed;
 import static org.apache.hadoop.hdfs.protocol.datatransfer.DataTransferProtoUtil.fromProto;
+import static org.apache.hadoop.hdfs.protocolPB.PBHelper.vintPrefixed;
 
 import java.io.DataInputStream;
 import java.io.IOException;
 
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
-import org.apache.hadoop.hdfs.ShortCircuitShm.SlotId;
+import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.CachingStrategyProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.OpBlockChecksumProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.OpCopyBlockProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.OpReadBlockProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.OpReplaceBlockProto;
-import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.OpTransferBlockProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.OpRequestShortCircuitAccessProto;
-import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.CachingStrategyProto;
+import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.OpTransferBlockProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.OpWriteBlockProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.ReleaseShortCircuitAccessRequestProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.ShortCircuitShmRequestProto;
 import org.apache.hadoop.hdfs.protocolPB.PBHelper;
 import org.apache.hadoop.hdfs.server.datanode.CachingStrategy;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.SlotId;
 
 /** Receiver */
 @InterfaceAudience.Private
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocol/datatransfer/Sender.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocol/datatransfer/Sender.java
index 7ef6ced4e45..c03f33fb276 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocol/datatransfer/Sender.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocol/datatransfer/Sender.java
@@ -25,24 +25,24 @@
 
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
-import org.apache.hadoop.hdfs.ShortCircuitShm.SlotId;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
+import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.CachingStrategyProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.ChecksumProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.ClientOperationHeaderProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.OpBlockChecksumProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.OpCopyBlockProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.OpReadBlockProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.OpReplaceBlockProto;
-import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.OpTransferBlockProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.OpRequestShortCircuitAccessProto;
-import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.CachingStrategyProto;
+import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.OpTransferBlockProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.OpWriteBlockProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.ReleaseShortCircuitAccessRequestProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.ShortCircuitShmRequestProto;
 import org.apache.hadoop.hdfs.protocolPB.PBHelper;
 import org.apache.hadoop.hdfs.security.token.block.BlockTokenIdentifier;
 import org.apache.hadoop.hdfs.server.datanode.CachingStrategy;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.SlotId;
 import org.apache.hadoop.security.token.Token;
 import org.apache.hadoop.util.DataChecksum;
 
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocolPB/PBHelper.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocolPB/PBHelper.java
index bea82934a03..e3f28dddf86 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocolPB/PBHelper.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocolPB/PBHelper.java
@@ -27,7 +27,6 @@
 import java.util.EnumSet;
 import java.util.List;
 
-import com.google.common.base.Preconditions;
 import org.apache.hadoop.fs.CacheFlag;
 import org.apache.hadoop.fs.ContentSummary;
 import org.apache.hadoop.fs.CreateFlag;
@@ -41,8 +40,6 @@
 import org.apache.hadoop.fs.permission.FsPermission;
 import org.apache.hadoop.ha.HAServiceProtocol.HAServiceState;
 import org.apache.hadoop.hdfs.DFSUtil;
-import org.apache.hadoop.hdfs.ShortCircuitShm.ShmId;
-import org.apache.hadoop.hdfs.ShortCircuitShm.SlotId;
 import org.apache.hadoop.hdfs.StorageType;
 import org.apache.hadoop.hdfs.protocol.Block;
 import org.apache.hadoop.hdfs.protocol.CacheDirectiveEntry;
@@ -73,10 +70,10 @@
 import org.apache.hadoop.hdfs.protocol.SnapshotDiffReport.DiffType;
 import org.apache.hadoop.hdfs.protocol.SnapshottableDirectoryStatus;
 import org.apache.hadoop.hdfs.protocol.proto.AclProtos.AclEntryProto;
-import org.apache.hadoop.hdfs.protocol.proto.AclProtos.AclStatusProto;
 import org.apache.hadoop.hdfs.protocol.proto.AclProtos.AclEntryProto.AclEntryScopeProto;
 import org.apache.hadoop.hdfs.protocol.proto.AclProtos.AclEntryProto.AclEntryTypeProto;
 import org.apache.hadoop.hdfs.protocol.proto.AclProtos.AclEntryProto.FsActionProto;
+import org.apache.hadoop.hdfs.protocol.proto.AclProtos.AclStatusProto;
 import org.apache.hadoop.hdfs.protocol.proto.AclProtos.GetAclStatusResponseProto;
 import org.apache.hadoop.hdfs.protocol.proto.ClientNamenodeProtocolProtos;
 import org.apache.hadoop.hdfs.protocol.proto.ClientNamenodeProtocolProtos.CacheDirectiveEntryProto;
@@ -93,9 +90,8 @@
 import org.apache.hadoop.hdfs.protocol.proto.ClientNamenodeProtocolProtos.RollingUpgradeActionProto;
 import org.apache.hadoop.hdfs.protocol.proto.ClientNamenodeProtocolProtos.RollingUpgradeInfoProto;
 import org.apache.hadoop.hdfs.protocol.proto.ClientNamenodeProtocolProtos.SafeModeActionProto;
-import org.apache.hadoop.hdfs.protocol.proto.ClientNamenodeProtocolProtos.CacheDirectiveInfoProto;
-import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.ShortCircuitShmSlotProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.ShortCircuitShmIdProto;
+import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.ShortCircuitShmSlotProto;
 import org.apache.hadoop.hdfs.protocol.proto.DatanodeProtocolProtos.BalancerBandwidthCommandProto;
 import org.apache.hadoop.hdfs.protocol.proto.DatanodeProtocolProtos.BlockCommandProto;
 import org.apache.hadoop.hdfs.protocol.proto.DatanodeProtocolProtos.BlockIdCommandProto;
@@ -189,6 +185,8 @@
 import org.apache.hadoop.hdfs.server.protocol.RemoteEditLog;
 import org.apache.hadoop.hdfs.server.protocol.RemoteEditLogManifest;
 import org.apache.hadoop.hdfs.server.protocol.StorageReport;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.ShmId;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.SlotId;
 import org.apache.hadoop.hdfs.util.ExactSizeInputStream;
 import org.apache.hadoop.io.EnumSetWritable;
 import org.apache.hadoop.io.Text;
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataXceiver.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataXceiver.java
index f390795fbf1..6d793507e07 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataXceiver.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataXceiver.java
@@ -46,7 +46,6 @@
 
 import org.apache.commons.logging.Log;
 import org.apache.hadoop.hdfs.ExtendedBlockId;
-import org.apache.hadoop.hdfs.ShortCircuitShm.SlotId;
 import org.apache.hadoop.hdfs.net.Peer;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
@@ -75,6 +74,7 @@
 import org.apache.hadoop.hdfs.server.datanode.ShortCircuitRegistry.NewShmInfo;
 import org.apache.hadoop.hdfs.server.datanode.fsdataset.LengthInputStream;
 import org.apache.hadoop.hdfs.server.protocol.DatanodeRegistration;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.SlotId;
 import org.apache.hadoop.io.IOUtils;
 import org.apache.hadoop.io.MD5Hash;
 import org.apache.hadoop.net.NetUtils;
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/ShortCircuitRegistry.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/ShortCircuitRegistry.java
index f7c1983bc13..9dba6a2085d 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/ShortCircuitRegistry.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/ShortCircuitRegistry.java
@@ -25,7 +25,6 @@
 import java.io.Closeable;
 import java.io.FileInputStream;
 import java.io.IOException;
-import java.util.Collections;
 import java.util.HashMap;
 import java.util.Iterator;
 import java.util.Set;
@@ -36,19 +35,16 @@
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.InvalidRequestException;
 import org.apache.hadoop.hdfs.ExtendedBlockId;
-import org.apache.hadoop.hdfs.ShortCircuitShm;
-import org.apache.hadoop.hdfs.ShortCircuitShm.ShmId;
-import org.apache.hadoop.hdfs.ShortCircuitShm.Slot;
-import org.apache.hadoop.hdfs.ShortCircuitShm.SlotId;
-import org.apache.hadoop.io.nativeio.NativeIO;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.ShmId;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.Slot;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.SlotId;
 import org.apache.hadoop.io.nativeio.SharedFileDescriptorFactory;
 import org.apache.hadoop.net.unix.DomainSocket;
 import org.apache.hadoop.net.unix.DomainSocketWatcher;
 
 import com.google.common.base.Preconditions;
-import com.google.common.base.Splitter;
 import com.google.common.collect.HashMultimap;
-import com.google.common.collect.Iterables;
 
 /*
  * Manages client short-circuit memory segments on the DataNode.
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/NamenodeFsck.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/NamenodeFsck.java
index fe227c6e075..c3605cc23fd 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/NamenodeFsck.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/NamenodeFsck.java
@@ -41,7 +41,6 @@
 import org.apache.hadoop.fs.UnresolvedLinkException;
 import org.apache.hadoop.hdfs.BlockReader;
 import org.apache.hadoop.hdfs.BlockReaderFactory;
-import org.apache.hadoop.hdfs.ClientContext;
 import org.apache.hadoop.hdfs.DFSClient;
 import org.apache.hadoop.hdfs.DFSConfigKeys;
 import org.apache.hadoop.hdfs.DFSUtil;
@@ -58,7 +57,6 @@
 import org.apache.hadoop.hdfs.protocol.SnapshottableDirectoryStatus;
 import org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicy;
 import org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementStatus;
-import org.apache.hadoop.hdfs.server.blockmanagement.DatanodeStorageInfo;
 import org.apache.hadoop.hdfs.server.blockmanagement.NumberReplicas;
 import org.apache.hadoop.hdfs.server.common.HdfsServerConstants;
 import org.apache.hadoop.hdfs.server.datanode.CachingStrategy;
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/client/ClientMmap.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/ClientMmap.java
similarity index 97%
rename from hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/client/ClientMmap.java
rename to hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/ClientMmap.java
index 98d932e3fe7..8184fdf3f86 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/client/ClientMmap.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/ClientMmap.java
@@ -15,7 +15,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package org.apache.hadoop.hdfs.client;
+package org.apache.hadoop.hdfs.shortcircuit;
 
 import org.apache.hadoop.classification.InterfaceAudience;
 
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/client/DfsClientShm.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/DfsClientShm.java
similarity index 95%
rename from hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/client/DfsClientShm.java
rename to hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/DfsClientShm.java
index da4ea6cf1f3..1c9a2e5a742 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/client/DfsClientShm.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/DfsClientShm.java
@@ -15,15 +15,14 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package org.apache.hadoop.hdfs.client;
+package org.apache.hadoop.hdfs.shortcircuit;
 
 import java.io.FileInputStream;
 import java.io.IOException;
 import java.util.Iterator;
 
-import org.apache.hadoop.hdfs.ShortCircuitShm;
-import org.apache.hadoop.hdfs.client.DfsClientShmManager.EndpointShmManager;
 import org.apache.hadoop.hdfs.net.DomainPeer;
+import org.apache.hadoop.hdfs.shortcircuit.DfsClientShmManager.EndpointShmManager;
 import org.apache.hadoop.net.unix.DomainSocket;
 import org.apache.hadoop.net.unix.DomainSocketWatcher;
 
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/client/DfsClientShmManager.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/DfsClientShmManager.java
similarity index 98%
rename from hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/client/DfsClientShmManager.java
rename to hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/DfsClientShmManager.java
index 0b4c8f8b9c7..ca9e8e6e0a5 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/client/DfsClientShmManager.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/DfsClientShmManager.java
@@ -15,10 +15,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package org.apache.hadoop.hdfs.client;
-
-import com.google.common.annotations.VisibleForTesting;
-import com.google.common.base.Preconditions;
+package org.apache.hadoop.hdfs.shortcircuit;
 
 import java.io.BufferedOutputStream;
 import java.io.Closeable;
@@ -27,26 +24,31 @@
 import java.io.FileInputStream;
 import java.io.IOException;
 import java.util.HashMap;
-import java.util.TreeMap;
 import java.util.Map.Entry;
+import java.util.TreeMap;
 import java.util.concurrent.locks.Condition;
 import java.util.concurrent.locks.ReentrantLock;
 
 import org.apache.commons.lang.mutable.MutableBoolean;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.hdfs.ExtendedBlockId;
-import org.apache.hadoop.hdfs.ShortCircuitShm.ShmId;
-import org.apache.hadoop.hdfs.ShortCircuitShm.Slot;
 import org.apache.hadoop.hdfs.net.DomainPeer;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
+import org.apache.hadoop.hdfs.protocol.datatransfer.DataTransferProtocol;
 import org.apache.hadoop.hdfs.protocol.datatransfer.Sender;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.ShortCircuitShmResponseProto;
 import org.apache.hadoop.hdfs.protocolPB.PBHelper;
+import org.apache.hadoop.hdfs.server.datanode.ShortCircuitRegistry;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.ShmId;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.Slot;
 import org.apache.hadoop.io.IOUtils;
 import org.apache.hadoop.net.unix.DomainSocket;
 import org.apache.hadoop.net.unix.DomainSocketWatcher;
-import org.apache.hadoop.classification.InterfaceAudience;
+
+import com.google.common.annotations.VisibleForTesting;
+import com.google.common.base.Preconditions;
 
 /**
  * Manages short-circuit memory segments for an HDFS client.
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DomainSocketFactory.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/DomainSocketFactory.java
similarity index 87%
rename from hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DomainSocketFactory.java
rename to hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/DomainSocketFactory.java
index 1bd4b424474..e067de7b4ad 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DomainSocketFactory.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/DomainSocketFactory.java
@@ -15,7 +15,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package org.apache.hadoop.hdfs;
+package org.apache.hadoop.hdfs.shortcircuit;
 
 import java.io.IOException;
 import java.net.InetSocketAddress;
@@ -23,16 +23,19 @@
 
 import org.apache.commons.io.IOUtils;
 import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.HadoopIllegalArgumentException;
+import org.apache.hadoop.hdfs.DFSClient;
 import org.apache.hadoop.hdfs.DFSClient.Conf;
+import org.apache.hadoop.hdfs.DFSConfigKeys;
 import org.apache.hadoop.net.unix.DomainSocket;
 
 import com.google.common.base.Preconditions;
 import com.google.common.cache.Cache;
 import com.google.common.cache.CacheBuilder;
 
-class DomainSocketFactory {
-  private static final Log LOG = BlockReaderLocal.LOG;
+public class DomainSocketFactory {
+  private static final Log LOG = LogFactory.getLog(DomainSocketFactory.class);
 
   public enum PathState {
     UNUSABLE(false, false),
@@ -93,9 +96,9 @@ public String toString() {
 
   public DomainSocketFactory(Conf conf) {
     final String feature;
-    if (conf.shortCircuitLocalReads && (!conf.useLegacyBlockReaderLocal)) {
+    if (conf.isShortCircuitLocalReads() && (!conf.isUseLegacyBlockReaderLocal())) {
       feature = "The short-circuit local reads feature";
-    } else if (conf.domainSocketDataTraffic) {
+    } else if (conf.isDomainSocketDataTraffic()) {
       feature = "UNIX domain socket data traffic";
     } else {
       feature = null;
@@ -104,7 +107,7 @@ public DomainSocketFactory(Conf conf) {
     if (feature == null) {
       LOG.debug("Both short-circuit local reads and UNIX domain socket are disabled.");
     } else {
-      if (conf.domainSocketPath.isEmpty()) {
+      if (conf.getDomainSocketPath().isEmpty()) {
         throw new HadoopIllegalArgumentException(feature + " is enabled but "
             + DFSConfigKeys.DFS_DOMAIN_SOCKET_PATH_KEY + " is not set.");
       } else if (DomainSocket.getLoadingFailureReason() != null) {
@@ -127,10 +130,10 @@ public DomainSocketFactory(Conf conf) {
   public PathInfo getPathInfo(InetSocketAddress addr, DFSClient.Conf conf) {
     // If there is no domain socket path configured, we can't use domain
     // sockets.
-    if (conf.domainSocketPath.isEmpty()) return PathInfo.NOT_CONFIGURED;
+    if (conf.getDomainSocketPath().isEmpty()) return PathInfo.NOT_CONFIGURED;
     // If we can't do anything with the domain socket, don't create it.
-    if (!conf.domainSocketDataTraffic &&
-        (!conf.shortCircuitLocalReads || conf.useLegacyBlockReaderLocal)) {
+    if (!conf.isDomainSocketDataTraffic() &&
+        (!conf.isShortCircuitLocalReads() || conf.isUseLegacyBlockReaderLocal())) {
       return PathInfo.NOT_CONFIGURED;
     }
     // If the DomainSocket code is not loaded, we can't create
@@ -140,8 +143,8 @@ public PathInfo getPathInfo(InetSocketAddress addr, DFSClient.Conf conf) {
     }
     // UNIX domain sockets can only be used to talk to local peers
     if (!DFSClient.isLocalAddress(addr)) return PathInfo.NOT_CONFIGURED;
-    String escapedPath = DomainSocket.
-        getEffectivePath(conf.domainSocketPath, addr.getPort());
+    String escapedPath = DomainSocket.getEffectivePath(
+        conf.getDomainSocketPath(), addr.getPort());
     PathState status = pathMap.getIfPresent(escapedPath);
     if (status == null) {
       return new PathInfo(escapedPath, PathState.VALID);
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/client/ShortCircuitCache.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/ShortCircuitCache.java
similarity index 99%
rename from hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/client/ShortCircuitCache.java
rename to hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/ShortCircuitCache.java
index e68d100fedd..1e7245df44b 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/client/ShortCircuitCache.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/ShortCircuitCache.java
@@ -15,15 +15,12 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package org.apache.hadoop.hdfs.client;
+package org.apache.hadoop.hdfs.shortcircuit;
 
 import java.io.BufferedOutputStream;
 import java.io.Closeable;
 import java.io.DataInputStream;
 import java.io.DataOutputStream;
-
-import org.apache.hadoop.classification.InterfaceAudience;
-
 import java.io.IOException;
 import java.nio.MappedByteBuffer;
 import java.util.HashMap;
@@ -39,17 +36,17 @@
 import org.apache.commons.lang.mutable.MutableBoolean;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.conf.Configuration;
-import org.apache.hadoop.hdfs.ExtendedBlockId;
 import org.apache.hadoop.hdfs.DFSConfigKeys;
-import org.apache.hadoop.hdfs.client.ShortCircuitReplica;
-import org.apache.hadoop.hdfs.ShortCircuitShm.Slot;
+import org.apache.hadoop.hdfs.ExtendedBlockId;
 import org.apache.hadoop.hdfs.net.DomainPeer;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.datatransfer.Sender;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.ReleaseShortCircuitAccessResponseProto;
 import org.apache.hadoop.hdfs.protocol.proto.DataTransferProtos.Status;
 import org.apache.hadoop.hdfs.protocolPB.PBHelper;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.Slot;
 import org.apache.hadoop.io.IOUtils;
 import org.apache.hadoop.ipc.RetriableException;
 import org.apache.hadoop.net.unix.DomainSocket;
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/client/ShortCircuitReplica.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/ShortCircuitReplica.java
similarity index 98%
rename from hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/client/ShortCircuitReplica.java
rename to hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/ShortCircuitReplica.java
index 9c0fbb0bc9c..85c79474fc7 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/client/ShortCircuitReplica.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/ShortCircuitReplica.java
@@ -15,9 +15,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package org.apache.hadoop.hdfs.client;
-
-import org.apache.hadoop.classification.InterfaceAudience;
+package org.apache.hadoop.hdfs.shortcircuit;
 
 import java.io.FileInputStream;
 import java.io.IOException;
@@ -27,9 +25,10 @@
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.hdfs.ExtendedBlockId;
-import org.apache.hadoop.hdfs.ShortCircuitShm.Slot;
 import org.apache.hadoop.hdfs.server.datanode.BlockMetadataHeader;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.Slot;
 import org.apache.hadoop.io.IOUtils;
 import org.apache.hadoop.io.nativeio.NativeIO;
 import org.apache.hadoop.util.Time;
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/client/ShortCircuitReplicaInfo.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/ShortCircuitReplicaInfo.java
similarity index 97%
rename from hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/client/ShortCircuitReplicaInfo.java
rename to hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/ShortCircuitReplicaInfo.java
index 54caf828728..ef0019ff579 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/client/ShortCircuitReplicaInfo.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/ShortCircuitReplicaInfo.java
@@ -15,7 +15,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package org.apache.hadoop.hdfs.client;
+package org.apache.hadoop.hdfs.shortcircuit;
 
 import org.apache.hadoop.security.token.SecretManager.InvalidToken;
 
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/ShortCircuitShm.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/ShortCircuitShm.java
similarity index 99%
rename from hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/ShortCircuitShm.java
rename to hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/ShortCircuitShm.java
index 3d53dbc7daa..d860c8b174c 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/ShortCircuitShm.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/shortcircuit/ShortCircuitShm.java
@@ -15,7 +15,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package org.apache.hadoop.hdfs;
+package org.apache.hadoop.hdfs.shortcircuit;
 
 import java.io.FileInputStream;
 import java.io.IOException;
@@ -30,17 +30,18 @@
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.fs.InvalidRequestException;
+import org.apache.hadoop.hdfs.ExtendedBlockId;
 import org.apache.hadoop.io.nativeio.NativeIO;
 import org.apache.hadoop.io.nativeio.NativeIO.POSIX;
 import org.apache.hadoop.util.Shell;
 import org.apache.hadoop.util.StringUtils;
 
+import sun.misc.Unsafe;
+
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ComparisonChain;
 import com.google.common.primitives.Ints;
 
-import sun.misc.Unsafe;
-
 /**
  * A shared memory segment used to implement short-circuit reads.
  */
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/fs/TestEnhancedByteBufferAccess.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/fs/TestEnhancedByteBufferAccess.java
index fc7160620d1..5040a3b6983 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/fs/TestEnhancedByteBufferAccess.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/fs/TestEnhancedByteBufferAccess.java
@@ -18,11 +18,11 @@
 package org.apache.hadoop.fs;
 
 import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CACHEREPORT_INTERVAL_MSEC_KEY;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_MMAP_CACHE_SIZE;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_MMAP_ENABLED;
 import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_DATANODE_MAX_LOCKED_MEMORY_KEY;
 import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_HEARTBEAT_INTERVAL_KEY;
 import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_NAMENODE_PATH_BASED_CACHE_REFRESH_INTERVAL_MS;
-import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_MMAP_ENABLED;
-import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_MMAP_CACHE_SIZE;
 
 import java.io.File;
 import java.io.FileInputStream;
@@ -30,36 +30,34 @@
 import java.io.IOException;
 import java.io.InputStream;
 import java.nio.ByteBuffer;
-import java.util.concurrent.TimeoutException;
 import java.util.Arrays;
 import java.util.EnumSet;
+import java.util.Map;
 import java.util.Random;
+import java.util.concurrent.TimeoutException;
 
 import org.apache.commons.lang.SystemUtils;
 import org.apache.commons.lang.mutable.MutableBoolean;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
-import org.apache.hadoop.fs.FSDataInputStream;
-import org.apache.hadoop.fs.FileSystem;
-import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hdfs.BlockReaderTestUtil;
-import org.apache.hadoop.hdfs.ExtendedBlockId;
 import org.apache.hadoop.hdfs.ClientContext;
 import org.apache.hadoop.hdfs.DFSClient;
 import org.apache.hadoop.hdfs.DFSConfigKeys;
 import org.apache.hadoop.hdfs.DFSTestUtil;
 import org.apache.hadoop.hdfs.DistributedFileSystem;
+import org.apache.hadoop.hdfs.ExtendedBlockId;
 import org.apache.hadoop.hdfs.HdfsConfiguration;
 import org.apache.hadoop.hdfs.MiniDFSCluster;
-import org.apache.hadoop.hdfs.ShortCircuitShm.Slot;
 import org.apache.hadoop.hdfs.client.HdfsDataInputStream;
-import org.apache.hadoop.hdfs.client.ShortCircuitCache;
-import org.apache.hadoop.hdfs.client.ShortCircuitCache.CacheVisitor;
-import org.apache.hadoop.hdfs.client.ShortCircuitReplica;
 import org.apache.hadoop.hdfs.protocol.CacheDirectiveInfo;
 import org.apache.hadoop.hdfs.protocol.CachePoolInfo;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
 import org.apache.hadoop.hdfs.server.datanode.fsdataset.FsDatasetSpi;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitCache;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitCache.CacheVisitor;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitReplica;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.Slot;
 import org.apache.hadoop.io.ByteBufferPool;
 import org.apache.hadoop.io.IOUtils;
 import org.apache.hadoop.io.nativeio.NativeIO;
@@ -74,8 +72,6 @@
 import org.junit.BeforeClass;
 import org.junit.Test;
 
-import java.util.Map;
-
 import com.google.common.base.Preconditions;
 import com.google.common.base.Supplier;
 
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/AppendTestUtil.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/AppendTestUtil.java
index b78d7075d86..eab44be13d2 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/AppendTestUtil.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/AppendTestUtil.java
@@ -72,7 +72,7 @@ protected Random initialValue() {
   static int nextInt(int n) {return RANDOM.get().nextInt(n);}
   static int nextLong() {return RANDOM.get().nextInt();}
 
-  static byte[] randomBytes(long seed, int size) {
+  public static byte[] randomBytes(long seed, int size) {
     LOG.info("seed=" + seed + ", size=" + size);
     final byte[] b = new byte[size];
     final Random rand = new Random(seed);
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/BlockReaderTestUtil.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/BlockReaderTestUtil.java
index 31060732ece..0de3ab2e915 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/BlockReaderTestUtil.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/BlockReaderTestUtil.java
@@ -31,9 +31,6 @@
 import org.apache.commons.io.IOUtils;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
-import org.apache.hadoop.hdfs.client.DfsClientShmManager;
-import org.apache.hadoop.hdfs.client.ShortCircuitCache;
-import org.apache.hadoop.hdfs.client.ShortCircuitReplica;
 import org.apache.hadoop.hdfs.net.Peer;
 import org.apache.hadoop.hdfs.net.TcpPeerServer;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
@@ -46,6 +43,10 @@
 import org.apache.hadoop.hdfs.server.datanode.ShortCircuitRegistry;
 import org.apache.hadoop.hdfs.server.datanode.fsdataset.impl.FsDatasetCache;
 import org.apache.hadoop.hdfs.server.namenode.CacheManager;
+import org.apache.hadoop.hdfs.shortcircuit.DfsClientShmManager;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitCache;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitReplica;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm;
 import org.apache.hadoop.net.NetUtils;
 import org.apache.log4j.Level;
 import org.apache.log4j.LogManager;
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestBlockReaderFactory.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestBlockReaderFactory.java
index 76e547d2e3d..09d4353d7f1 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestBlockReaderFactory.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestBlockReaderFactory.java
@@ -17,26 +17,35 @@
  */
 package org.apache.hadoop.hdfs;
 
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_BLOCK_SIZE_KEY;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_CONTEXT;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_DOMAIN_SOCKET_DATA_TRAFFIC;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_READ_SHORTCIRCUIT_KEY;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_READ_SHORTCIRCUIT_SKIP_CHECKSUM_KEY;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_DOMAIN_SOCKET_PATH_KEY;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_SHORT_CIRCUIT_SHARED_MEMORY_WATCHER_INTERRUPT_CHECK_MS;
+import static org.hamcrest.CoreMatchers.equalTo;
+
 import java.io.File;
 import java.io.IOException;
 import java.util.Arrays;
 import java.util.HashMap;
 import java.util.List;
 import java.util.concurrent.CountDownLatch;
-import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicBoolean;
 
-import org.apache.commons.logging.LogFactory;
 import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
-import org.apache.hadoop.hdfs.client.DfsClientShmManager.PerDatanodeVisitorInfo;
-import org.apache.hadoop.hdfs.client.DfsClientShmManager.Visitor;
-import org.apache.hadoop.hdfs.client.ShortCircuitCache;
-import org.apache.hadoop.hdfs.client.ShortCircuitReplicaInfo;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.LocatedBlock;
+import org.apache.hadoop.hdfs.shortcircuit.DfsClientShmManager.PerDatanodeVisitorInfo;
+import org.apache.hadoop.hdfs.shortcircuit.DfsClientShmManager.Visitor;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitCache;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitReplicaInfo;
 import org.apache.hadoop.net.unix.DomainSocket;
 import org.apache.hadoop.net.unix.TemporarySocketDirectory;
 import org.junit.After;
@@ -47,15 +56,6 @@
 
 import com.google.common.util.concurrent.Uninterruptibles;
 
-import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_BLOCK_SIZE_KEY;
-import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_CONTEXT;
-import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_DOMAIN_SOCKET_PATH_KEY;
-import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_READ_SHORTCIRCUIT_KEY;
-import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_READ_SHORTCIRCUIT_SKIP_CHECKSUM_KEY;
-import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_SHORT_CIRCUIT_SHARED_MEMORY_WATCHER_INTERRUPT_CHECK_MS;
-import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_DOMAIN_SOCKET_DATA_TRAFFIC;
-import static org.hamcrest.CoreMatchers.equalTo;
-
 public class TestBlockReaderFactory {
   static final Log LOG = LogFactory.getLog(TestBlockReaderFactory.class);
 
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestBlockReaderLocal.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestBlockReaderLocal.java
index 10d25c614e9..9b4fef6ae94 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestBlockReaderLocal.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestBlockReaderLocal.java
@@ -17,6 +17,8 @@
  */
 package org.apache.hadoop.hdfs;
 
+import static org.hamcrest.CoreMatchers.equalTo;
+
 import java.io.EOFException;
 import java.io.File;
 import java.io.FileInputStream;
@@ -30,14 +32,14 @@
 import org.apache.hadoop.fs.FSDataInputStream;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
-import org.apache.hadoop.hdfs.ShortCircuitShm.ShmId;
 import org.apache.hadoop.hdfs.client.HdfsDataInputStream;
-import org.apache.hadoop.hdfs.client.ShortCircuitCache;
-import org.apache.hadoop.hdfs.client.ShortCircuitReplica;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
 import org.apache.hadoop.hdfs.server.datanode.CachingStrategy;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitCache;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitReplica;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.ShmId;
 import org.apache.hadoop.io.IOUtils;
-import org.apache.hadoop.io.nativeio.SharedFileDescriptorFactory;
 import org.apache.hadoop.net.unix.DomainSocket;
 import org.apache.hadoop.net.unix.TemporarySocketDirectory;
 import org.apache.hadoop.util.Time;
@@ -47,8 +49,6 @@
 import org.junit.BeforeClass;
 import org.junit.Test;
 
-import static org.hamcrest.CoreMatchers.equalTo;
-
 public class TestBlockReaderLocal {
   private static TemporarySocketDirectory sockDir;
   
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestDataTransferKeepalive.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestDataTransferKeepalive.java
index 132218c37a6..003e6be273b 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestDataTransferKeepalive.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestDataTransferKeepalive.java
@@ -17,19 +17,17 @@
  */
 package org.apache.hadoop.hdfs;
 
-import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_MAX_BLOCK_ACQUIRE_FAILURES_KEY;
-import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_DATANODE_SOCKET_REUSE_KEEPALIVE_KEY;
-import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_DATANODE_SOCKET_REUSE_KEEPALIVE_DEFAULT;
-import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_DATANODE_SOCKET_WRITE_TIMEOUT_KEY;
-import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_SOCKET_CACHE_EXPIRY_MSEC_KEY;
 import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_CONTEXT;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_MAX_BLOCK_ACQUIRE_FAILURES_KEY;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_SOCKET_CACHE_EXPIRY_MSEC_KEY;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_DATANODE_SOCKET_REUSE_KEEPALIVE_DEFAULT;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_DATANODE_SOCKET_REUSE_KEEPALIVE_KEY;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_DATANODE_SOCKET_WRITE_TIMEOUT_KEY;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 
-import com.google.common.base.Supplier;
-
 import java.io.InputStream;
 import java.io.PrintWriter;
 
@@ -47,6 +45,7 @@
 import org.junit.Before;
 import org.junit.Test;
 
+import com.google.common.base.Supplier;
 import com.google.common.io.NullOutputStream;
 
 public class TestDataTransferKeepalive {
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestPeerCache.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestPeerCache.java
index b3a97b78315..243d09b78c1 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestPeerCache.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestPeerCache.java
@@ -17,7 +17,15 @@
  */
 package org.apache.hadoop.hdfs;
 
-import com.google.common.collect.HashMultiset;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertSame;
+import static org.junit.Assert.assertTrue;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.nio.channels.ReadableByteChannel;
+
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.hdfs.net.Peer;
@@ -28,12 +36,7 @@
 import org.mockito.invocation.InvocationOnMock;
 import org.mockito.stubbing.Answer;
 
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.OutputStream;
-import java.nio.channels.ReadableByteChannel;
-
-import static org.junit.Assert.*;
+import com.google.common.collect.HashMultiset;
 
 public class TestPeerCache {
   static final Log LOG = LogFactory.getLog(TestPeerCache.class);
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/blockmanagement/TestBlockTokenWithDFS.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/blockmanagement/TestBlockTokenWithDFS.java
index 92b3d8c7934..8def7324625 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/blockmanagement/TestBlockTokenWithDFS.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/blockmanagement/TestBlockTokenWithDFS.java
@@ -20,7 +20,6 @@
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
 
 import java.io.IOException;
 import java.net.InetSocketAddress;
@@ -43,10 +42,7 @@
 import org.apache.hadoop.hdfs.DFSConfigKeys;
 import org.apache.hadoop.hdfs.DFSTestUtil;
 import org.apache.hadoop.hdfs.MiniDFSCluster;
-import org.apache.hadoop.hdfs.DFSClient.Conf;
 import org.apache.hadoop.hdfs.RemotePeerFactory;
-import org.apache.hadoop.hdfs.client.ShortCircuitCache;
-import org.apache.hadoop.hdfs.client.ShortCircuitReplica;
 import org.apache.hadoop.hdfs.net.Peer;
 import org.apache.hadoop.hdfs.net.TcpPeerServer;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
@@ -63,9 +59,7 @@
 import org.apache.hadoop.hdfs.server.protocol.NamenodeProtocols;
 import org.apache.hadoop.io.IOUtils;
 import org.apache.hadoop.net.NetUtils;
-import org.apache.hadoop.security.UserGroupInformation;
 import org.apache.hadoop.security.token.Token;
-import org.apache.hadoop.util.StringUtils;
 import org.apache.log4j.Level;
 import org.junit.Assert;
 import org.junit.Test;
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/TestDataNodeVolumeFailure.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/TestDataNodeVolumeFailure.java
index 2e7a88f140e..3644c33a76d 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/TestDataNodeVolumeFailure.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/TestDataNodeVolumeFailure.java
@@ -58,7 +58,6 @@
 import org.apache.hadoop.hdfs.server.protocol.StorageBlockReport;
 import org.apache.hadoop.io.IOUtils;
 import org.apache.hadoop.net.NetUtils;
-import org.apache.hadoop.security.UserGroupInformation;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestShortCircuitCache.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/shortcircuit/TestShortCircuitCache.java
similarity index 95%
rename from hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestShortCircuitCache.java
rename to hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/shortcircuit/TestShortCircuitCache.java
index 1f53eec9250..d62b3eb3201 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestShortCircuitCache.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/shortcircuit/TestShortCircuitCache.java
@@ -15,7 +15,23 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package org.apache.hadoop.hdfs;
+package org.apache.hadoop.hdfs.shortcircuit;
+
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_BLOCK_SIZE_KEY;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_CONTEXT;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_DOMAIN_SOCKET_DATA_TRAFFIC;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_READ_SHORTCIRCUIT_KEY;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_READ_SHORTCIRCUIT_SKIP_CHECKSUM_KEY;
+import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_DOMAIN_SOCKET_PATH_KEY;
+import static org.hamcrest.CoreMatchers.equalTo;
+
+import java.io.DataOutputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
 
 import org.apache.commons.lang.mutable.MutableBoolean;
 import org.apache.commons.logging.Log;
@@ -23,18 +39,21 @@
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.FSDataInputStream;
 import org.apache.hadoop.fs.Path;
-import org.apache.hadoop.hdfs.ShortCircuitShm.Slot;
-import org.apache.hadoop.hdfs.client.DfsClientShmManager.PerDatanodeVisitorInfo;
-import org.apache.hadoop.hdfs.client.ShortCircuitCache;
-import org.apache.hadoop.hdfs.client.ShortCircuitCache.CacheVisitor;
-import org.apache.hadoop.hdfs.client.ShortCircuitCache.ShortCircuitReplicaCreator;
-import org.apache.hadoop.hdfs.client.DfsClientShmManager.Visitor;
-import org.apache.hadoop.hdfs.client.ShortCircuitReplica;
-import org.apache.hadoop.hdfs.client.ShortCircuitReplicaInfo;
+import org.apache.hadoop.hdfs.BlockReaderTestUtil;
+import org.apache.hadoop.hdfs.DFSInputStream;
+import org.apache.hadoop.hdfs.DFSTestUtil;
+import org.apache.hadoop.hdfs.DistributedFileSystem;
+import org.apache.hadoop.hdfs.ExtendedBlockId;
+import org.apache.hadoop.hdfs.MiniDFSCluster;
 import org.apache.hadoop.hdfs.net.DomainPeer;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
 import org.apache.hadoop.hdfs.server.datanode.BlockMetadataHeader;
+import org.apache.hadoop.hdfs.shortcircuit.DfsClientShmManager.PerDatanodeVisitorInfo;
+import org.apache.hadoop.hdfs.shortcircuit.DfsClientShmManager.Visitor;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitCache.CacheVisitor;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitCache.ShortCircuitReplicaCreator;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.Slot;
 import org.apache.hadoop.io.IOUtils;
 import org.apache.hadoop.net.unix.DomainSocket;
 import org.apache.hadoop.net.unix.TemporarySocketDirectory;
@@ -49,22 +68,6 @@
 import com.google.common.base.Preconditions;
 import com.google.common.base.Supplier;
 
-import java.io.DataOutputStream;
-import java.io.File;
-import java.io.FileInputStream;
-import java.io.FileOutputStream;
-import java.io.IOException;
-import java.util.HashMap;
-import java.util.Map;
-
-import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_BLOCK_SIZE_KEY;
-import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_CONTEXT;
-import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_DOMAIN_SOCKET_PATH_KEY;
-import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_READ_SHORTCIRCUIT_KEY;
-import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_READ_SHORTCIRCUIT_SKIP_CHECKSUM_KEY;
-import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_CLIENT_DOMAIN_SOCKET_DATA_TRAFFIC;
-import static org.hamcrest.CoreMatchers.equalTo;
-
 public class TestShortCircuitCache {
   static final Log LOG = LogFactory.getLog(TestShortCircuitCache.class);
   
@@ -402,7 +405,7 @@ public void testAllocShm() throws Exception {
     cluster.waitActive();
     DistributedFileSystem fs = cluster.getFileSystem();
     final ShortCircuitCache cache =
-        fs.dfs.getClientContext().getShortCircuitCache();
+        fs.getClient().getClientContext().getShortCircuitCache();
     cache.getDfsClientShmManager().visit(new Visitor() {
       @Override
       public void visit(HashMap<DatanodeInfo, PerDatanodeVisitorInfo> info)
@@ -470,7 +473,7 @@ public void testShmBasedStaleness() throws Exception {
     cluster.waitActive();
     DistributedFileSystem fs = cluster.getFileSystem();
     final ShortCircuitCache cache =
-        fs.dfs.getClientContext().getShortCircuitCache();
+        fs.getClient().getClientContext().getShortCircuitCache();
     String TEST_FILE = "/test_file";
     final int TEST_FILE_LEN = 8193;
     final int SEED = 0xFADED;
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestShortCircuitLocalRead.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/shortcircuit/TestShortCircuitLocalRead.java
similarity index 97%
rename from hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestShortCircuitLocalRead.java
rename to hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/shortcircuit/TestShortCircuitLocalRead.java
index 37034a73e1c..bf27ffb6ef0 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestShortCircuitLocalRead.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/shortcircuit/TestShortCircuitLocalRead.java
@@ -15,10 +15,11 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package org.apache.hadoop.hdfs;
+package org.apache.hadoop.hdfs.shortcircuit;
 
-import static org.junit.Assert.assertTrue;
+import static org.hamcrest.CoreMatchers.equalTo;
 import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
 
 import java.io.EOFException;
 import java.io.File;
@@ -35,9 +36,17 @@
 import org.apache.hadoop.fs.FSDataOutputStream;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
+import org.apache.hadoop.hdfs.AppendTestUtil;
+import org.apache.hadoop.hdfs.ClientContext;
+import org.apache.hadoop.hdfs.DFSClient;
+import org.apache.hadoop.hdfs.DFSConfigKeys;
+import org.apache.hadoop.hdfs.DFSTestUtil;
+import org.apache.hadoop.hdfs.DFSUtil;
+import org.apache.hadoop.hdfs.DistributedFileSystem;
+import org.apache.hadoop.hdfs.HdfsConfiguration;
+import org.apache.hadoop.hdfs.MiniDFSCluster;
+import org.apache.hadoop.hdfs.TestBlockReaderLocal;
 import org.apache.hadoop.hdfs.client.HdfsDataInputStream;
-import org.apache.hadoop.hdfs.client.ShortCircuitCache;
-import org.apache.hadoop.hdfs.client.ShortCircuitReplica;
 import org.apache.hadoop.hdfs.protocol.ClientDatanodeProtocol;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
@@ -59,8 +68,6 @@
 import org.junit.BeforeClass;
 import org.junit.Test;
 
-import static org.hamcrest.CoreMatchers.*;
-
 /**
  * Test for short circuit read functionality using {@link BlockReaderLocal}.
  * When a block is being read by a client is on the local datanode, instead of
@@ -342,8 +349,7 @@ public DistributedFileSystem run() throws Exception {
   }
   
   @Test(timeout=10000)
-  public void testDeprecatedGetBlockLocalPathInfoRpc()
-      throws IOException, InterruptedException {
+  public void testDeprecatedGetBlockLocalPathInfoRpc() throws IOException {
     final Configuration conf = new Configuration();
     MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).numDataNodes(1)
         .format(true).build();
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/client/TestShortCircuitShm.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/shortcircuit/TestShortCircuitShm.java
similarity index 93%
rename from hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/client/TestShortCircuitShm.java
rename to hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/shortcircuit/TestShortCircuitShm.java
index 5c9b98969c3..7d28736ae41 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/client/TestShortCircuitShm.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/shortcircuit/TestShortCircuitShm.java
@@ -15,7 +15,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package org.apache.hadoop.hdfs.client;
+package org.apache.hadoop.hdfs.shortcircuit;
 
 import java.io.File;
 import java.io.FileInputStream;
@@ -25,15 +25,15 @@
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.fs.FileUtil;
-import org.apache.hadoop.io.nativeio.SharedFileDescriptorFactory;
 import org.apache.hadoop.hdfs.ExtendedBlockId;
-import org.apache.hadoop.hdfs.ShortCircuitShm;
-import org.apache.hadoop.hdfs.ShortCircuitShm.ShmId;
-import org.apache.hadoop.hdfs.ShortCircuitShm.Slot;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.ShmId;
+import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.Slot;
+import org.apache.hadoop.io.nativeio.SharedFileDescriptorFactory;
+import org.junit.Assert;
 import org.junit.Assume;
 import org.junit.Before;
 import org.junit.Test;
-import org.junit.Assert;
 
 public class TestShortCircuitShm {
   public static final Log LOG = LogFactory.getLog(TestShortCircuitShm.class);