HDFS-11060. make DEFAULT_MAX_CORRUPT_FILEBLOCKS_RETURNED configurable. Contributed by Lantao Jin.

(cherry picked from commit e95c5e9f62452ee848875ec2f8642eab4992cd23)
(cherry picked from commit 964f3454d1237fa25aa828504612b4a11d8e76ff)
(cherry picked from commit 0af04ad89f2e3d867ed4011d519a53b764e3be6e)

Conflicts:
	hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSConfigKeys.java

(cherry picked from commit 5ef8fd5119a76dcf821970f5bc643127bd34fe92)

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSConfigKeys.java

@@ -219,6 +219,10 @@ public class DFSConfigKeys extends CommonConfigurationKeys {
       "dfs.namenode.maintenance.replication.min";
   public static final int     DFS_NAMENODE_MAINTENANCE_REPLICATION_MIN_DEFAULT
       = 1;
+
+  public static final String  DFS_NAMENODE_MAX_CORRUPT_FILE_BLOCKS_RETURNED_KEY = "dfs.namenode.max-corrupt-file-blocks-returned";
+  public static final int     DFS_NAMENODE_MAX_CORRUPT_FILE_BLOCKS_RETURNED_DEFAULT = 100;
+
   public static final String  DFS_NAMENODE_REPLICATION_MAX_STREAMS_KEY =
       HdfsClientConfigKeys.DeprecatedKeys.DFS_NAMENODE_REPLICATION_MAX_STREAMS_KEY;
   public static final int     DFS_NAMENODE_REPLICATION_MAX_STREAMS_DEFAULT = 2;

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java

@@ -393,7 +393,7 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
   public static final Log auditLog = LogFactory.getLog(
       FSNamesystem.class.getName() + ".audit");
 
-  static final int DEFAULT_MAX_CORRUPT_FILEBLOCKS_RETURNED = 100;
+  private final int maxCorruptFileBlocksReturn;
   static int BLOCK_DELETION_INCREMENT = 1000;
   private final boolean isPermissionEnabled;
   private final UserGroupInformation fsOwner;
@@ -796,6 +796,10 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
       this.supportAppends = conf.getBoolean(DFS_SUPPORT_APPEND_KEY, DFS_SUPPORT_APPEND_DEFAULT);
       LOG.info("Append Enabled: " + supportAppends);
 
+      this.maxCorruptFileBlocksReturn = conf.getInt(
+          DFSConfigKeys.DFS_NAMENODE_MAX_CORRUPT_FILE_BLOCKS_RETURNED_KEY,
+          DFSConfigKeys.DFS_NAMENODE_MAX_CORRUPT_FILE_BLOCKS_RETURNED_DEFAULT);
+
       this.dtpReplaceDatanodeOnFailure = ReplaceDatanodeOnFailure.get(conf);
       
       this.standbyShouldCheckpoint = conf.getBoolean(
@@ -5135,7 +5139,7 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
           if (src.startsWith(path)){
             corruptFiles.add(new CorruptFileBlockInfo(src, blk));
             count++;
-            if (count >= DEFAULT_MAX_CORRUPT_FILEBLOCKS_RETURNED)
+            if (count >= maxCorruptFileBlocksReturn)
               break;
           }
         }

hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml

@@ -591,6 +591,15 @@
   </description>
 </property>
 
+<property>
+  <name>dfs.namenode.max-corrupt-file-blocks-returned</name>
+  <value>100</value>
+  <description>
+      The maximum number of corrupt file blocks listed by NameNode Web UI,
+      JMX and other client request.
+  </description>
+</property>
+
 <property>
   <name>dfs.blocksize</name>
   <value>134217728</value>

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestListCorruptFileBlocks.java

@@ -452,7 +452,7 @@ public class TestListCorruptFileBlocks {
       cluster = new MiniDFSCluster.Builder(conf).build();
       FileSystem fs = cluster.getFileSystem();
       final int maxCorruptFileBlocks = 
-        FSNamesystem.DEFAULT_MAX_CORRUPT_FILEBLOCKS_RETURNED;
+        conf.getInt(DFSConfigKeys.DFS_NAMENODE_MAX_CORRUPT_FILE_BLOCKS_RETURNED_KEY, 100);
 
       // create 110 files with one block each
       DFSTestUtil util = new DFSTestUtil.Builder().setName("testMaxCorruptFiles").