[svn-r16393] Description:

	Connect extensible array as index for 1-D unlimited datasets (although
datasets w/filters are not yet supported).

Tested on:
        FreeBSD/32 6.3 (duty) in debug mode
        FreeBSD/64 6.3 (liberty) w/C++ & FORTRAN, in debug mode
        Linux/32 2.6 (jam) w/PGI compilers, w/C++ & FORTRAN, w/threadsafe,
                                in debug mode
        Linux/64-amd64 2.6 (smirom) w/Intel compilers w/default API=1.6.x,
                                w/C++ & FORTRAN, in production mode
        Solaris/32 2.10 (linew) w/deprecated symbols disabled, w/C++ & FORTRAN,
                                w/szip filter, in production mode
        Linux/64-ia64 2.6 (cobalt) w/Intel compilers, w/C++ & FORTRAN,
                                in production mode
        Linux/64-ia64 2.4 (tg-login3) w/parallel, w/FORTRAN, in production mode
        Linux/64-amd64 2.6 (abe) w/parallel, w/FORTRAN, in production mode
        Mac OS X/32 10.5.6 (amazon) in debug mode
        Mac OS X/32 10.5.6 (amazon) w/C++ & FORTRAN, w/threadsafe,
                                in production mode

12 files changed, 1466 insertions, 77 deletions

diff --git a/src/H5Dbtree.c b/src/H5Dbtree.c
index b0988c1..86a86cb 100644
--- a/src/H5Dbtree.c
+++ b/src/H5Dbtree.c
@@ -16,29 +16,10 @@
 /* Programmer: 	Robb Matzke <matzke@llnl.gov>
  *	       	Wednesday, October  8, 1997
  *
- * Purpose:	v1 B-tree indexed (chunked) I/O functions.  The logical
- *		multi-dimensional data space is regularly partitioned into
- *		same-sized "chunks", the first of which is aligned with the
- *		logical origin.  The chunks are given a multi-dimensional
- *		index which is used as a lookup key in a B-tree that maps
- *		chunk index to disk address.  Each chunk can be compressed
- *		independently and the chunks may move around in the file as
- *		their storage requirements change.
- *
- * Cache:	Disk I/O is performed in units of chunks and H5MF_alloc()
- *		contains code to optionally align chunks on disk block
- *		boundaries for performance.
- *
- *		The chunk cache is an extendible hash indexed by a function
- *		of storage B-tree address and chunk N-dimensional offset
- *		within the dataset.  Collisions are not resolved -- one of
- *		the two chunks competing for the hash slot must be preempted
- *		from the cache.  All entries in the hash also participate in
- *		a doubly-linked list and entries are penalized by moving them
- *		toward the front of the list.  When a new chunk is about to
- *		be added to the cache the heap is pruned by preempting
- *		entries near the front of the list to make room for the new
- *		entry which is added to the end of the list.
+ * Purpose:	v1 B-tree indexed (chunked) I/O functions.  The chunks are
+ *              given a multi-dimensional index which is used as a lookup key
+ *              in a B-tree that maps chunk index to disk address.
+ *
  */
 
 /****************/
@@ -169,7 +150,7 @@ static herr_t H5D_btree_idx_delete(const H5D_chk_idx_info_t *idx_info);
 static herr_t H5D_btree_idx_copy_setup(const H5D_chk_idx_info_t *idx_info_src,
     const H5D_chk_idx_info_t *idx_info_dst);
 static herr_t H5D_btree_idx_copy_shutdown(H5O_layout_t *layout_src,
-    H5O_layout_t *layout_dst);
+    H5O_layout_t *layout_dst, hid_t dxpl_id);
 static herr_t H5D_btree_idx_size(const H5D_chk_idx_info_t *idx_info,
     hsize_t *size);
 static herr_t H5D_btree_idx_reset(H5O_layout_t *layout);
@@ -1079,7 +1060,7 @@ H5D_btree_idx_iterate_cb(H5F_t UNUSED *f, hid_t UNUSED dxpl_id,
 /*-------------------------------------------------------------------------
  * Function:	H5D_btree_idx_iterate
  *
- * Purpose:	Iterate over the chunks in the B-tree index, making a callback
+ * Purpose:	Iterate over the chunks in an index, making a callback
  *              for each one.
  *
  * Return:	Non-negative on success/Negative on failure
@@ -1122,7 +1103,7 @@ H5D_btree_idx_iterate(const H5D_chk_idx_info_t *idx_info,
 /*-------------------------------------------------------------------------
  * Function:	H5D_btree_idx_remove
  *
- * Purpose:	Remove chunk from v1 B-tree index.
+ * Purpose:	Remove chunk from index.
  *
  * Return:	Non-negative on success/Negative on failure
  *
@@ -1158,7 +1139,7 @@ done:
 /*-------------------------------------------------------------------------
  * Function:	H5D_btree_idx_delete
  *
- * Purpose:	Delete v1 B-tree index and raw data storage for entire dataset
+ * Purpose:	Delete index and raw data storage for entire dataset
  *              (i.e. all chunks)
  *
  * Return:	Success:	Non-negative
@@ -1268,7 +1249,8 @@ done:
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5D_btree_idx_copy_shutdown(H5O_layout_t *layout_src, H5O_layout_t *layout_dst)
+H5D_btree_idx_copy_shutdown(H5O_layout_t *layout_src, H5O_layout_t *layout_dst,
+    hid_t UNUSED dxpl_id)
 {
     herr_t      ret_value = SUCCEED;       /* Return value */
 
@@ -1291,7 +1273,7 @@ done:
 /*-------------------------------------------------------------------------
  * Function:    H5D_btree_idx_size
  *
- * Purpose:     Retrieve the amount of B-tree storage for chunked dataset
+ * Purpose:     Retrieve the amount of index storage for chunked dataset
  *
  * Return:      Success:        Non-negative
  *              Failure:        negative
@@ -1301,10 +1283,10 @@ done:
  *
  *-------------------------------------------------------------------------
  */
-herr_t
+static herr_t
 H5D_btree_idx_size(const H5D_chk_idx_info_t *idx_info, hsize_t *index_size)
 {
-    H5D_btree_ud0_t udata;             /* User-data for loading btree nodes */
+    H5D_btree_ud0_t udata;              /* User-data for loading B-tree nodes */
     H5B_info_t bt_info;                 /* B-tree info */
     hbool_t shared_init = FALSE;        /* Whether shared B-tree info is initialized */
     herr_t ret_value = SUCCEED;         /* Return value */
@@ -1322,7 +1304,7 @@ H5D_btree_idx_size(const H5D_chk_idx_info_t *idx_info, hsize_t *index_size)
         HGOTO_ERROR(H5E_RESOURCE, H5E_CANTINIT, FAIL, "can't create wrapper for shared B-tree info")
     shared_init = TRUE;
 
-    /* Initialize btree node user-data */
+    /* Initialize B-tree node user-data */
     HDmemset(&udata, 0, sizeof udata);
     udata.mesg = idx_info->layout;
 
diff --git a/src/H5Dchunk.c b/src/H5Dchunk.c
index afcdc6d..1437d58 100644
--- a/src/H5Dchunk.c
+++ b/src/H5Dchunk.c
@@ -13,6 +13,33 @@
  * access to either file, you may request a copy from help@hdfgroup.org.     *
  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
+/* Programmer: 	Quincey Koziol <koziol@hdfgroup.org>
+ *	       	Thursday, April 24, 2008
+ *
+ * Purpose:	Abstract indexed (chunked) I/O functions.  The logical
+ *		multi-dimensional data space is regularly partitioned into
+ *		same-sized "chunks", the first of which is aligned with the
+ *		logical origin.  The chunks are indexed by different methods,
+ *		that map a chunk index to disk address.  Each chunk can be
+ *              compressed independently and the chunks may move around in the
+ *              file as their storage requirements change.
+ *
+ * Cache:	Disk I/O is performed in units of chunks and H5MF_alloc()
+ *		contains code to optionally align chunks on disk block
+ *		boundaries for performance.
+ *
+ *		The chunk cache is an extendible hash indexed by a function
+ *		of storage B-tree address and chunk N-dimensional offset
+ *		within the dataset.  Collisions are not resolved -- one of
+ *		the two chunks competing for the hash slot must be preempted
+ *		from the cache.  All entries in the hash also participate in
+ *		a doubly-linked list and entries are penalized by moving them
+ *		toward the front of the list.  When a new chunk is about to
+ *		be added to the cache the heap is pruned by preempting
+ *		entries near the front of the list to make room for the new
+ *		entry which is added to the end of the list.
+ */
+
 /****************/
 /* Module Setup */
 /****************/
@@ -319,6 +346,10 @@ H5D_chunk_new(H5F_t *f, hid_t dapl_id, hid_t dxpl_id, H5D_t *dset,
     /* Retain computed chunk size */
     H5_ASSIGN_OVERFLOW(dset->shared->layout.u.chunk.size, chunk_size, uint64_t, uint32_t);
 
+    /* Reset index address */
+    if(H5D_chunk_idx_reset(&dset->shared->layout) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTINIT, FAIL, "unable to reset chunked storage index")
+
     /* Initialize the chunk cache for the dataset */
     if(H5D_chunk_init(f, dapl_id, dxpl_id, dset) < 0)
         HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "can't initialize chunk cache")
@@ -349,6 +380,10 @@ H5D_chunk_is_space_alloc(const H5O_layout_t *layout)
 
     /* Sanity checks */
     HDassert(layout);
+    HDassert((H5D_CHUNK_EARRAY == layout->u.chunk.idx_type && 
+                H5D_COPS_EARRAY == layout->u.chunk.ops) ||
+            (H5D_CHUNK_BTREE == layout->u.chunk.idx_type && 
+                H5D_COPS_BTREE == layout->u.chunk.ops));
 
     /* Query index layer */
     ret_value = (layout->u.chunk.ops->is_space_alloc)(layout);
@@ -1778,6 +1813,10 @@ H5D_chunk_init(H5F_t *f, hid_t dapl_id, hid_t dxpl_id, const H5D_t *dset)
     /* Sanity check */
     HDassert(f);
     HDassert(dset);
+    HDassert((H5D_CHUNK_EARRAY == dset->shared->layout.u.chunk.idx_type && 
+                H5D_COPS_EARRAY == dset->shared->layout.u.chunk.ops) ||
+            (H5D_CHUNK_BTREE == dset->shared->layout.u.chunk.idx_type && 
+                H5D_COPS_BTREE == dset->shared->layout.u.chunk.ops));
 
     if(NULL == (dapl = (H5P_genplist_t *)H5I_object(dapl_id)))
         HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "can't find object for fapl ID");
@@ -1816,7 +1855,7 @@ H5D_chunk_init(H5F_t *f, hid_t dapl_id, hid_t dxpl_id, const H5D_t *dset)
     idx_info.layout = &dset->shared->layout;
 
     /* Allocate any indexing structures */
-    if((dset->shared->layout.u.chunk.ops->init)(&idx_info) < 0)
+    if(dset->shared->layout.u.chunk.ops->init && (dset->shared->layout.u.chunk.ops->init)(&idx_info) < 0)
 	HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "can't initialize indexing information")
 
 done:
@@ -1846,6 +1885,10 @@ H5D_chunk_idx_reset(H5O_layout_t *layout)
     /* Sanity checks */
     HDassert(layout);
     HDassert(layout->u.chunk.ops);
+    HDassert((H5D_CHUNK_EARRAY == layout->u.chunk.idx_type && 
+                H5D_COPS_EARRAY == layout->u.chunk.ops) ||
+            (H5D_CHUNK_BTREE == layout->u.chunk.idx_type && 
+                H5D_COPS_BTREE == layout->u.chunk.ops));
 
     /* Reset index structures */
     if((layout->u.chunk.ops->reset)(layout) < 0)
@@ -1997,6 +2040,10 @@ H5D_chunk_create(H5D_t *dset /*in,out*/, hid_t dxpl_id)
     HDassert(dset);
     HDassert(H5D_CHUNKED == dset->shared->layout.type);
     HDassert(dset->shared->layout.u.chunk.ndims > 0 && dset->shared->layout.u.chunk.ndims <= H5O_LAYOUT_NDIMS);
+    HDassert((H5D_CHUNK_EARRAY == dset->shared->layout.u.chunk.idx_type && 
+                H5D_COPS_EARRAY == dset->shared->layout.u.chunk.ops) ||
+            (H5D_CHUNK_BTREE == dset->shared->layout.u.chunk.idx_type && 
+                H5D_COPS_BTREE == dset->shared->layout.u.chunk.ops));
 #ifndef NDEBUG
 {
     unsigned u;                         /* Local index variable */
@@ -2044,6 +2091,10 @@ H5D_chunk_get_info(const H5D_t *dset, hid_t dxpl_id, const hsize_t *chunk_offset
 
     HDassert(dset);
     HDassert(dset->shared->layout.u.chunk.ndims > 0);
+    HDassert((H5D_CHUNK_EARRAY == dset->shared->layout.u.chunk.idx_type && 
+                H5D_COPS_EARRAY == dset->shared->layout.u.chunk.ops) ||
+            (H5D_CHUNK_BTREE == dset->shared->layout.u.chunk.idx_type && 
+                H5D_COPS_BTREE == dset->shared->layout.u.chunk.ops));
     HDassert(chunk_offset);
     HDassert(udata);
 
@@ -2104,6 +2155,11 @@ H5D_chunk_flush_entry(const H5D_t *dset, hid_t dxpl_id, const H5D_dxpl_cache_t *
     FUNC_ENTER_NOAPI_NOINIT(H5D_chunk_flush_entry)
 
     HDassert(dset);
+    HDassert(dset->shared);
+    HDassert((H5D_CHUNK_EARRAY == dset->shared->layout.u.chunk.idx_type && 
+                H5D_COPS_EARRAY == dset->shared->layout.u.chunk.ops) ||
+            (H5D_CHUNK_BTREE == dset->shared->layout.u.chunk.idx_type && 
+                H5D_COPS_BTREE == dset->shared->layout.u.chunk.ops));
     HDassert(dxpl_cache);
     HDassert(ent);
     HDassert(!ent->locked);
@@ -2863,6 +2919,11 @@ H5D_chunk_allocated(H5D_t *dset, hid_t dxpl_id, hsize_t *nbytes)
     FUNC_ENTER_NOAPI(H5D_chunk_allocated, FAIL)
 
     HDassert(dset);
+    HDassert(dset->shared);
+    HDassert((H5D_CHUNK_EARRAY == dset->shared->layout.u.chunk.idx_type && 
+                H5D_COPS_EARRAY == dset->shared->layout.u.chunk.ops) ||
+            (H5D_CHUNK_BTREE == dset->shared->layout.u.chunk.idx_type && 
+                H5D_COPS_BTREE == dset->shared->layout.u.chunk.ops));
 
     /* Fill the DXPL cache values for later use */
     if(H5D_get_dxpl_cache(dxpl_id, &dxpl_cache) < 0)
@@ -2880,7 +2941,7 @@ H5D_chunk_allocated(H5D_t *dset, hid_t dxpl_id, hsize_t *nbytes)
     idx_info.dxpl_id = dxpl_id;
     idx_info.layout = &dset->shared->layout;
 
-    /* Call the index-specific "get all the allocated chunks sizes" routine */
+    /* Iterate over the chunks */
     if((dset->shared->layout.u.chunk.ops->iterate)(&idx_info, H5D_chunk_allocated_cb, &chunk_bytes) < 0)
         HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "unable to retrieve allocated chunk information from index")
 
@@ -2941,6 +3002,10 @@ H5D_chunk_allocate(H5D_t *dset, hid_t dxpl_id, hbool_t full_overwrite)
     /* Check args */
     HDassert(dset && H5D_CHUNKED == layout->type);
     HDassert(layout->u.chunk.ndims > 0 && layout->u.chunk.ndims <= H5O_LAYOUT_NDIMS);
+    HDassert((H5D_CHUNK_EARRAY == layout->u.chunk.idx_type && 
+                H5D_COPS_EARRAY == layout->u.chunk.ops) ||
+            (H5D_CHUNK_BTREE == layout->u.chunk.idx_type && 
+                H5D_COPS_BTREE == layout->u.chunk.ops));
     HDassert(TRUE == H5P_isa_class(dxpl_id, H5P_DATASET_XFER));
 
     /* Retrieve the dataset dimensions */
@@ -3512,6 +3577,10 @@ H5D_chunk_prune_by_extent(H5D_t *dset, hid_t dxpl_id, const hsize_t *old_dims)
     /* Check args */
     HDassert(dset && H5D_CHUNKED == layout->type);
     HDassert(layout->u.chunk.ndims > 0 && layout->u.chunk.ndims <= H5O_LAYOUT_NDIMS);
+    HDassert((H5D_CHUNK_EARRAY == layout->u.chunk.idx_type && 
+                H5D_COPS_EARRAY == layout->u.chunk.ops) ||
+            (H5D_CHUNK_BTREE == layout->u.chunk.idx_type && 
+                H5D_COPS_BTREE == layout->u.chunk.ops));
     HDassert(dxpl_cache);
 
     /* Fill the DXPL cache values for later use */
@@ -3680,6 +3749,11 @@ H5D_chunk_addrmap(const H5D_io_info_t *io_info, haddr_t chunk_addr[],
     FUNC_ENTER_NOAPI(H5D_chunk_addrmap, FAIL)
 
     HDassert(dset);
+    HDassert(dset->shared);
+    HDassert((H5D_CHUNK_EARRAY == dset->shared->layout.u.chunk.idx_type && 
+                H5D_COPS_EARRAY == dset->shared->layout.u.chunk.ops) ||
+            (H5D_CHUNK_BTREE == dset->shared->layout.u.chunk.idx_type && 
+                H5D_COPS_BTREE == dset->shared->layout.u.chunk.ops));
     HDassert(chunk_addr);
     HDassert(down_chunks);
 
@@ -3725,6 +3799,12 @@ H5D_chunk_delete(H5F_t *f, hid_t dxpl_id, H5O_layout_t *layout)
 
     FUNC_ENTER_NOAPI(H5D_chunk_delete, FAIL)
 
+    /* Sanity check */
+    HDassert((H5D_CHUNK_EARRAY == layout->u.chunk.idx_type && 
+                H5D_COPS_EARRAY == layout->u.chunk.ops) ||
+            (H5D_CHUNK_BTREE == layout->u.chunk.idx_type && 
+                H5D_COPS_BTREE == layout->u.chunk.ops));
+
     /* Compose chunked index info struct */
     idx_info.f = f;
     idx_info.dxpl_id = dxpl_id;
@@ -4052,7 +4132,15 @@ H5D_chunk_copy(H5F_t *f_src, H5O_layout_t *layout_src, H5F_t *f_dst,
     HDassert(f_src);
     HDassert(f_dst);
     HDassert(layout_src && H5D_CHUNKED == layout_src->type);
+    HDassert((H5D_CHUNK_EARRAY == layout_src->u.chunk.idx_type && 
+                H5D_COPS_EARRAY == layout_src->u.chunk.ops) ||
+            (H5D_CHUNK_BTREE == layout_src->u.chunk.idx_type && 
+                H5D_COPS_BTREE == layout_src->u.chunk.ops));
     HDassert(layout_dst && H5D_CHUNKED == layout_dst->type);
+    HDassert((H5D_CHUNK_EARRAY == layout_dst->u.chunk.idx_type && 
+                H5D_COPS_EARRAY == layout_dst->u.chunk.ops) ||
+            (H5D_CHUNK_BTREE == layout_dst->u.chunk.idx_type && 
+                H5D_COPS_BTREE == layout_dst->u.chunk.ops));
     HDassert(dt_src);
 
     /* Compose source & dest chunked index info structs */
@@ -4218,7 +4306,7 @@ done:
 
     /* Clean up any index information */
     if(copy_setup_done)
-        if((layout_src->u.chunk.ops->copy_shutdown)(layout_src, layout_dst) < 0)
+        if((layout_src->u.chunk.ops->copy_shutdown)(layout_src, layout_dst, dxpl_id) < 0)
             HDONE_ERROR(H5E_DATASET, H5E_CANTRELEASE, FAIL, "unable to shut down index copying info")
 
     FUNC_LEAVE_NOAPI(ret_value)
@@ -4250,6 +4338,10 @@ H5D_chunk_bh_info(H5F_t *f, hid_t dxpl_id, H5O_layout_t *layout,
     /* Check args */
     HDassert(f);
     HDassert(layout);
+    HDassert((H5D_CHUNK_EARRAY == layout->u.chunk.idx_type && 
+                H5D_COPS_EARRAY == layout->u.chunk.ops) ||
+            (H5D_CHUNK_BTREE == layout->u.chunk.idx_type && 
+                H5D_COPS_BTREE == layout->u.chunk.ops));
     HDassert(index_size);
 
     /* Compose chunked index info struct */
@@ -4335,6 +4427,10 @@ H5D_chunk_dump_index(H5D_t *dset, hid_t dxpl_id, FILE *stream)
 
     /* Sanity check */
     HDassert(dset);
+    HDassert((H5D_CHUNK_EARRAY == dset->shared->layout.u.chunk.idx_type && 
+                H5D_COPS_EARRAY == dset->shared->layout.u.chunk.ops) ||
+            (H5D_CHUNK_BTREE == dset->shared->layout.u.chunk.idx_type && 
+                H5D_COPS_BTREE == dset->shared->layout.u.chunk.ops));
 
     /* Only display info if stream is defined */
     if(stream) {
@@ -4393,6 +4489,10 @@ H5D_chunk_dest(H5F_t *f, hid_t dxpl_id, H5D_t *dset)
 
     HDassert(f);
     HDassert(dset);
+    HDassert((H5D_CHUNK_EARRAY == dset->shared->layout.u.chunk.idx_type && 
+                H5D_COPS_EARRAY == dset->shared->layout.u.chunk.ops) ||
+            (H5D_CHUNK_BTREE == dset->shared->layout.u.chunk.idx_type && 
+                H5D_COPS_BTREE == dset->shared->layout.u.chunk.ops));
 
     /* Fill the DXPL cache values for later use */
     if(H5D_get_dxpl_cache(dxpl_id, &dxpl_cache) < 0)
diff --git a/src/H5Dearray.c b/src/H5Dearray.c
new file mode 100644
index 0000000..02747c5
--- /dev/null
+++ b/src/H5Dearray.c
@@ -0,0 +1,1111 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by The HDF Group.                                               *
+ * Copyright by the Board of Trustees of the University of Illinois.         *
+ * All rights reserved.                                                      *
+ *                                                                           *
+ * This file is part of HDF5.  The full HDF5 copyright notice, including     *
+ * terms governing use, modification, and redistribution, is contained in    *
+ * the files COPYING and Copyright.html.  COPYING can be found at the root   *
+ * of the source code distribution tree; Copyright.html can be found at the  *
+ * root level of an installed copy of the electronic HDF5 document set and   *
+ * is linked from the top-level documents page.  It can also be found at     *
+ * http://hdfgroup.org/HDF5/doc/Copyright.html.  If you do not have          *
+ * access to either file, you may request a copy from help@hdfgroup.org.     *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/* Programmer: 	Quincey Koziol <koziol@hdfgroup.org>
+ *	       	Tuesday, January 27, 2009
+ *
+ * Purpose:	Extensible array indexed (chunked) I/O functions.  The chunks
+ *              are given a single-dimensional index which is used as the
+ *              offset in an extensible array that maps a chunk coordinate to
+ *              a disk address.
+ *
+ */
+
+/****************/
+/* Module Setup */
+/****************/
+
+#define H5D_PACKAGE		/*suppress error about including H5Dpkg	  */
+
+
+/***********/
+/* Headers */
+/***********/
+#include "H5private.h"		/* Generic Functions			*/
+#include "H5Dpkg.h"		/* Datasets				*/
+#include "H5Eprivate.h"		/* Error handling		  	*/
+#include "H5EAprivate.h"	/* Extensible arrays		  	*/
+#include "H5FLprivate.h"	/* Free Lists                           */
+#include "H5MFprivate.h"	/* File space management		*/
+#include "H5Vprivate.h"         /* Vector functions			*/
+
+
+/****************/
+/* Local Macros */
+/****************/
+
+/* Value to fill unset array elements with */
+#define H5D_EARRAY_FILL         HADDR_UNDEF
+
+/* Extensible array creation values */
+#define H5D_EARRAY_MAX_NELMTS_BITS         32                      /* i.e. 4 giga-elements */
+#define H5D_EARRAY_IDX_BLK_ELMTS           4
+#define H5D_EARRAY_SUP_BLK_MIN_DATA_PTRS   4
+#define H5D_EARRAY_DATA_BLK_MIN_ELMTS      16
+#define H5D_EARRAY_MAX_DBLOCK_PAGE_NELMTS_BITS     10              /* i.e. 1024 elements per data block page */
+
+
+/******************/
+/* Local Typedefs */
+/******************/
+
+/* Extensible array callback context */
+typedef struct H5D_earray_ctx_t {
+    size_t file_addr_len;       /* Size of addresses in the file        */
+} H5D_earray_ctx_t;
+
+/* User data for chunk callbacks */
+typedef struct H5D_earray_ud_t {
+    H5F_t *f;                   /* File pointer for operation */
+    hid_t dxpl_id;              /* DXPL ID for operation */
+} H5D_earray_ud_t;
+
+
+/********************/
+/* Local Prototypes */
+/********************/
+
+/* Extensible array class callbacks */
+static void *H5D_earray_crt_context(const H5F_t *f);
+static herr_t H5D_earray_dst_context(void *ctx);
+static herr_t H5D_earray_fill(void *nat_blk, size_t nelmts);
+static herr_t H5D_earray_encode(void *raw, const void *elmt, size_t nelmts,
+    void *ctx);
+static herr_t H5D_earray_decode(const void *raw, void *elmt, size_t nelmts,
+    void *ctx);
+static herr_t H5D_earray_debug(FILE *stream, int indent, int fwidth,
+    hsize_t idx, const void *elmt);
+
+/* Chunked layout indexing callbacks */
+static herr_t H5D_earray_idx_create(const H5D_chk_idx_info_t *idx_info);
+static hbool_t H5D_earray_idx_is_space_alloc(const H5O_layout_t *layout);
+static herr_t H5D_earray_idx_insert(const H5D_chk_idx_info_t *idx_info,
+    H5D_chunk_ud_t *udata);
+static herr_t H5D_earray_idx_get_addr(const H5D_chk_idx_info_t *idx_info,
+    H5D_chunk_ud_t *udata);
+static int H5D_earray_idx_iterate(const H5D_chk_idx_info_t *idx_info,
+    H5D_chunk_cb_func_t chunk_cb, void *chunk_udata);
+static herr_t H5D_earray_idx_remove(const H5D_chk_idx_info_t *idx_info,
+    H5D_chunk_common_ud_t *udata);
+static herr_t H5D_earray_idx_delete(const H5D_chk_idx_info_t *idx_info);
+static herr_t H5D_earray_idx_copy_setup(const H5D_chk_idx_info_t *idx_info_src,
+    const H5D_chk_idx_info_t *idx_info_dst);
+static herr_t H5D_earray_idx_copy_shutdown(H5O_layout_t *layout_src,
+    H5O_layout_t *layout_dst, hid_t dxpl_id);
+static herr_t H5D_earray_idx_size(const H5D_chk_idx_info_t *idx_info,
+    hsize_t *size);
+static herr_t H5D_earray_idx_reset(H5O_layout_t *layout);
+static herr_t H5D_earray_idx_dump(const H5D_chk_idx_info_t *idx_info,
+    FILE *stream);
+static herr_t H5D_earray_idx_dest(const H5D_chk_idx_info_t *idx_info);
+
+
+/*********************/
+/* Package Variables */
+/*********************/
+
+/* Extensible array indexed chunk I/O ops */
+const H5D_chunk_ops_t H5D_COPS_EARRAY[1] = {{
+    NULL,
+    H5D_earray_idx_create,
+    H5D_earray_idx_is_space_alloc,
+    H5D_earray_idx_insert,
+    H5D_earray_idx_get_addr,
+    H5D_earray_idx_iterate,
+    H5D_earray_idx_remove,
+    H5D_earray_idx_delete,
+    H5D_earray_idx_copy_setup,
+    H5D_earray_idx_copy_shutdown,
+    H5D_earray_idx_size,
+    H5D_earray_idx_reset,
+    H5D_earray_idx_dump,
+    H5D_earray_idx_dest
+}};
+
+
+/*****************************/
+/* Library Private Variables */
+/*****************************/
+
+
+/*******************/
+/* Local Variables */
+/*******************/
+
+/* Extensible array class callbacks for dataset chunks */
+const H5EA_class_t H5EA_CLS_CHUNK[1]={{
+    H5EA_CLS_CHUNK_ID,          /* Type of extensible array */
+    sizeof(haddr_t),            /* Size of native element */
+    H5D_earray_crt_context,     /* Create context */
+    H5D_earray_dst_context,     /* Destroy context */
+    H5D_earray_fill,            /* Fill block of missing elements callback */
+    H5D_earray_encode,          /* Element encoding callback */
+    H5D_earray_decode,          /* Element decoding callback */
+    H5D_earray_debug            /* Element debugging callback */
+}};
+
+/* Declare a free list to manage the H5D_earray_ctx_t struct */
+H5FL_DEFINE_STATIC(H5D_earray_ctx_t);
+
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5D_earray_crt_context
+ *
+ * Purpose:	Create context for callbacks
+ *
+ * Return:	Success:	non-NULL
+ *		Failure:	NULL
+ *
+ * Programmer:	Quincey Koziol
+ *              Thursday, January 29, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static void *
+H5D_earray_crt_context(const H5F_t *f)
+{
+    H5D_earray_ctx_t *ctx;      /* Extensible array callback context */
+    void *ret_value;            /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5D_earray_crt_context)
+
+    /* Sanity checks */
+    HDassert(f);
+
+    /* Allocate new context structure */
+    if(NULL == (ctx = H5FL_MALLOC(H5D_earray_ctx_t)))
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, NULL, "can't allocate extensible array client callback context")
+
+    /* Initialize the context */
+    ctx->file_addr_len = H5F_SIZEOF_ADDR(f);
+
+    /* Set return value */
+    ret_value = ctx;
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5D_earray_crt_context() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5D_earray_dst_context
+ *
+ * Purpose:	Destroy context for callbacks
+ *
+ * Return:	Success:	non-NULL
+ *		Failure:	NULL
+ *
+ * Programmer:	Quincey Koziol
+ *              Thursday, January 29, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5D_earray_dst_context(void *_ctx)
+{
+    H5D_earray_ctx_t *ctx = (H5D_earray_ctx_t *)_ctx;   /* Extensible array callback context */
+
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5D_earray_dst_context)
+
+    /* Sanity checks */
+    HDassert(ctx);
+
+    /* Release context structure */
+    ctx = H5FL_FREE(H5D_earray_ctx_t, ctx);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5D_earray_dst_context() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5D_earray_fill
+ *
+ * Purpose:	Fill "missing elements" in block of elements
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Tuesday, January 27, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5D_earray_fill(void *nat_blk, size_t nelmts)
+{
+    haddr_t fill_val = H5D_EARRAY_FILL;          /* Value to fill elements with */
+
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5D_earray_fill)
+
+    /* Sanity checks */
+    HDassert(nat_blk);
+    HDassert(nelmts);
+
+    H5V_array_fill(nat_blk, &fill_val, H5EA_CLS_CHUNK->nat_elmt_size, nelmts);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5D_earray_fill() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5D_earray_encode
+ *
+ * Purpose:	Encode an element from "native" to "raw" form
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Tuesday, January 27, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5D_earray_encode(void *raw, const void *_elmt, size_t nelmts, void *_ctx)
+{
+    H5D_earray_ctx_t *ctx = (H5D_earray_ctx_t *)_ctx;   /* Extensible array callback context */
+    const haddr_t *elmt = (const haddr_t *)_elmt;     /* Convenience pointer to native elements */
+
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5D_earray_encode)
+
+    /* Sanity checks */
+    HDassert(raw);
+    HDassert(elmt);
+    HDassert(nelmts);
+    HDassert(ctx);
+
+    /* Encode native elements into raw elements */
+    while(nelmts) {
+        /* Encode element */
+        /* (advances 'raw' pointer */
+        H5F_addr_encode_len(ctx->file_addr_len, (uint8_t **)&raw, *elmt);
+
+        /* Advance native element pointer */
+        elmt++;
+
+        /* Decrement # of elements to encode */
+        nelmts--;
+    } /* end while */
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5D_earray_encode() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5D_earray_decode
+ *
+ * Purpose:	Decode an element from "raw" to "native" form
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Thursday, January 29, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5D_earray_decode(const void *_raw, void *_elmt, size_t nelmts, void *_ctx)
+{
+    H5D_earray_ctx_t *ctx = (H5D_earray_ctx_t *)_ctx;   /* Extensible array callback context */
+    haddr_t *elmt = (haddr_t *)_elmt;           /* Convenience pointer to native elements */
+    const uint8_t *raw = (const uint8_t *)_raw; /* Convenience pointer to raw elements */
+
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5D_earray_decode)
+
+    /* Sanity checks */
+    HDassert(raw);
+    HDassert(elmt);
+    HDassert(nelmts);
+
+    /* Decode raw elements into native elements */
+    while(nelmts) {
+        /* Decode element */
+        /* (advances 'raw' pointer */
+        H5F_addr_decode_len(ctx->file_addr_len, &raw, elmt);
+
+        /* Advance native element pointer */
+        elmt++;
+
+        /* Decrement # of elements to decode */
+        nelmts--;
+    } /* end while */
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5D_earray_decode() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5D_earray_debug
+ *
+ * Purpose:	Display an element for debugging
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Thursday, January 29, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5D_earray_debug(FILE *stream, int indent, int fwidth, hsize_t idx,
+    const void *elmt)
+{
+    char temp_str[128];     /* Temporary string, for formatting */
+
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5D_earray_debug)
+
+    /* Sanity checks */
+    HDassert(stream);
+    HDassert(elmt);
+
+    /* Print element */
+    sprintf(temp_str, "Element #%llu:", (unsigned long_long)idx);
+    HDfprintf(stream, "%*s%-*s %a\n", indent, "", fwidth, temp_str,
+        *(const haddr_t *)elmt);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5D_earray_debug() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5D_earray_idx_open
+ *
+ * Purpose:	Opens an existing extensible array and initializes
+ *              the layout struct with information about the storage.
+ *
+ * Return:	Success:	non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *		Thursday, January 29, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5D_earray_idx_open(const H5D_chk_idx_info_t *idx_info)
+{
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5D_earray_idx_open)
+
+    /* Check args */
+    HDassert(idx_info);
+    HDassert(idx_info->f);
+    HDassert(idx_info->layout);
+    HDassert(H5D_CHUNK_EARRAY == idx_info->layout->u.chunk.idx_type);
+    HDassert(H5F_addr_defined(idx_info->layout->u.chunk.u.earray.addr));
+    HDassert(NULL == idx_info->layout->u.chunk.u.earray.ea);
+
+    /* Open the extensible array for the chunk index */
+    if(NULL == (idx_info->layout->u.chunk.u.earray.ea = H5EA_open(idx_info->f, idx_info->dxpl_id, idx_info->layout->u.chunk.u.earray.addr, H5EA_CLS_CHUNK)))
+	HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "can't open extensible array")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5D_earray_idx_open() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5D_earray_idx_create
+ *
+ * Purpose:	Creates a new indexed-storage extensible array and initializes
+ *              the layout struct with information about the storage.  The
+ *		struct should be immediately written to the object header.
+ *
+ *		This function must be called before passing LAYOUT to any of
+ *		the other indexed storage functions!
+ *
+ * Return:	Non-negative on success (with the LAYOUT argument initialized
+ *		and ready to write to an object header). Negative on failure.
+ *
+ * Programmer:	Quincey Koziol
+ *		Tuesday, January 27, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5D_earray_idx_create(const H5D_chk_idx_info_t *idx_info)
+{
+    H5EA_create_t cparam;               /* Extensible array creation parameters */
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5D_earray_idx_create)
+
+    /* Check args */
+    HDassert(idx_info);
+    HDassert(idx_info->f);
+    HDassert(idx_info->layout);
+    HDassert(!H5F_addr_defined(idx_info->layout->u.chunk.u.earray.addr));
+    HDassert(NULL == idx_info->layout->u.chunk.u.earray.ea);
+
+    /* General parameters */
+    cparam.cls = H5EA_CLS_CHUNK;
+    cparam.raw_elmt_size = (uint8_t)H5F_SIZEOF_ADDR(idx_info->f);
+    cparam.max_nelmts_bits = H5D_EARRAY_MAX_NELMTS_BITS;
+    cparam.idx_blk_elmts = H5D_EARRAY_IDX_BLK_ELMTS;
+    cparam.sup_blk_min_data_ptrs = H5D_EARRAY_SUP_BLK_MIN_DATA_PTRS;
+    cparam.data_blk_min_elmts = H5D_EARRAY_DATA_BLK_MIN_ELMTS;
+    cparam.max_dblk_page_nelmts_bits = H5D_EARRAY_MAX_DBLOCK_PAGE_NELMTS_BITS;
+
+    /* Create the extensible array for the chunk index */
+    if(NULL == (idx_info->layout->u.chunk.u.earray.ea = H5EA_create(idx_info->f, idx_info->dxpl_id, &cparam)))
+	HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "can't create extensible array")
+
+    /* Get the address of the extensible array in file */
+    if(H5EA_get_addr(idx_info->layout->u.chunk.u.earray.ea, &(idx_info->layout->u.chunk.u.earray.addr)) < 0)
+	HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't query extensible array address")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5D_earray_idx_create() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5D_earray_idx_is_space_alloc
+ *
+ * Purpose:	Query if space is allocated for index method
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		Thursday, January 29, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static hbool_t
+H5D_earray_idx_is_space_alloc(const H5O_layout_t *layout)
+{
+    hbool_t ret_value;          /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5D_earray_idx_is_space_alloc)
+
+    /* Check args */
+    HDassert(layout);
+
+    /* Set return value */
+    ret_value = (hbool_t)H5F_addr_defined(layout->u.chunk.u.earray.addr);
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5D_earray_idx_is_space_alloc() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5D_earray_idx_insert
+ *
+ * Purpose:	Create the chunk it if it doesn't exist, or reallocate the
+ *              chunk if its size changed.
+ *
+ * Note:	Doesn't support reallocating chunks that change size yet
+ *              (as chunks w/filters aren't supported yet)
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *              Thursday, January 29, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5D_earray_idx_insert(const H5D_chk_idx_info_t *idx_info, H5D_chunk_ud_t *udata)
+{
+    H5EA_t      *ea;                    /* Pointer to extensible array structure */
+    haddr_t     addr = HADDR_UNDEF;     /* Address of chunk in file */
+    hsize_t     idx;                    /* Array index of chunk */
+    herr_t	ret_value = SUCCEED;	/* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5D_earray_idx_insert)
+
+    HDassert(idx_info);
+    HDassert(idx_info->f);
+    HDassert(idx_info->layout);
+    HDassert(idx_info->layout->u.chunk.ndims == 2);     /* (for now) */
+    HDassert(H5F_addr_defined(idx_info->layout->u.chunk.u.earray.addr));
+    HDassert(udata);
+
+    /* Check if the extensible array is open yet */
+    if(NULL == idx_info->layout->u.chunk.u.earray.ea) {
+        /* Open the extensible array in file */
+        if(H5D_earray_idx_open(idx_info) < 0)
+            HGOTO_ERROR(H5E_DATASET, H5E_CANTOPENOBJ, FAIL, "can't open extensible array")
+    } /* end if */
+
+    /* Set convenience pointer to extensible array structure */
+    ea = idx_info->layout->u.chunk.u.earray.ea;
+
+    /* Compute array index for chunk offset */
+    idx = udata->common.offset[0] / idx_info->layout->u.chunk.dim[0];
+
+#ifndef NDEBUG
+    /* Get the address for the chunk */
+    if(H5EA_get(ea, idx_info->dxpl_id, idx, &addr) < 0)
+	HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get chunk address")
+    HDassert(!H5F_addr_defined(addr));
+    addr = HADDR_UNDEF;
+#endif /* NDEBUG */
+
+    /*
+     * Create the chunk it if it doesn't exist, or reallocate the chunk if
+     * its size changed.
+     */
+    /* (not yet) */
+    HDassert(!H5F_addr_defined(udata->addr));
+    HDassert(udata->nbytes == idx_info->layout->u.chunk.size);
+
+    /*
+     * Allocate storage for the new chunk
+     */
+    H5_CHECK_OVERFLOW(udata->nbytes, /*From: */uint32_t, /*To: */hsize_t);
+    udata->addr = H5MF_alloc(idx_info->f, H5FD_MEM_DRAW, idx_info->dxpl_id, (hsize_t)udata->nbytes);
+    if(!H5F_addr_defined(udata->addr))
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "file allocation failed")
+
+    /* Set the address for the chunk */
+    if(H5EA_set(ea, idx_info->dxpl_id, idx, &udata->addr) < 0)
+	HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get chunk address")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5D_earray_idx_insert() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5D_earraye_idx_get_addr
+ *
+ * Purpose:	Get the file address of a chunk if file space has been
+ *		assigned.  Save the retrieved information in the udata
+ *		supplied.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *              Thursday, January 29, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5D_earray_idx_get_addr(const H5D_chk_idx_info_t *idx_info, H5D_chunk_ud_t *udata)
+{
+    H5EA_t      *ea;                    /* Pointer to extensible array structure */
+    hsize_t     idx;                    /* Array index of chunk */
+    herr_t	ret_value = SUCCEED;	/* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5D_earray_idx_get_addr)
+
+    HDassert(idx_info);
+    HDassert(idx_info->f);
+    HDassert(idx_info->layout);
+    HDassert(idx_info->layout->u.chunk.ndims == 2);     /* (for now) */
+    HDassert(H5F_addr_defined(idx_info->layout->u.chunk.u.earray.addr));
+    HDassert(udata);
+
+    /* Check if the extensible array is open yet */
+    if(NULL == idx_info->layout->u.chunk.u.earray.ea) {
+        /* Open the extensible array in file */
+        if(H5D_earray_idx_open(idx_info) < 0)
+            HGOTO_ERROR(H5E_DATASET, H5E_CANTOPENOBJ, FAIL, "can't open extensible array")
+    } /* end if */
+
+    /* Set convenience pointer to extensible array structure */
+    ea = idx_info->layout->u.chunk.u.earray.ea;
+
+    /* Compute array index for chunk offset */
+    idx = udata->common.offset[0] / idx_info->layout->u.chunk.dim[0];
+
+    /* Get the address for the chunk */
+    if(H5EA_get(ea, idx_info->dxpl_id, idx, &udata->addr) < 0)
+	HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get chunk address")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5D_earray_idx_get_addr() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5D_earray_idx_iterate
+ *
+ * Purpose:	Iterate over the chunks in an index, making a callback
+ *              for each one.
+ *
+ * Note:	This implementation is slow, particularly for sparse
+ *              extensible arrays, replace it with call to H5EA_iterate()
+ *              when that's available.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *              Thursday, January 29, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static int
+H5D_earray_idx_iterate(const H5D_chk_idx_info_t *idx_info,
+    H5D_chunk_cb_func_t chunk_cb, void *chunk_udata)
+{
+    H5EA_t      *ea;            /* Pointer to extensible array structure */
+    H5EA_stat_t ea_stat;        /* Extensible array statistics */
+    int ret_value;              /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5D_earray_idx_iterate)
+
+    HDassert(idx_info);
+    HDassert(idx_info->f);
+    HDassert(idx_info->layout);
+    HDassert(H5F_addr_defined(idx_info->layout->u.chunk.u.earray.addr));
+    HDassert(chunk_cb);
+    HDassert(chunk_udata);
+
+    /* Check if the extensible array is open yet */
+    if(NULL == idx_info->layout->u.chunk.u.earray.ea) {
+        /* Open the extensible array in file */
+        if(H5D_earray_idx_open(idx_info) < 0)
+            HGOTO_ERROR(H5E_DATASET, H5E_CANTOPENOBJ, FAIL, "can't open extensible array")
+    } /* end if */
+
+    /* Set convenience pointer to extensible array structure */
+    ea = idx_info->layout->u.chunk.u.earray.ea;
+
+    /* Get the extensible array statistics */
+    if(H5EA_get_stats(ea, &ea_stat) < 0)
+	HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't query extensible array statistics")
+
+    /* Check if there are any array elements */
+    if(ea_stat.max_idx_set > 0) {
+        H5D_chunk_rec_t chunk_rec;  /* Generic chunk record for callback */
+        hsize_t u;              /* Local index variable */
+
+        /* Prepare common fields of chunk record for callback */
+        /* (Note: these are not common for chunks w/filters) */
+        HDmemset(&chunk_rec, 0, sizeof(chunk_rec));
+        chunk_rec.nbytes = idx_info->layout->u.chunk.size;
+        chunk_rec.filter_mask = 0;
+
+        /* Loop over array elements */
+        /* (Note: this is too simple for datasets with >1 dimension) */
+        for(u = 0; u < ea_stat.max_idx_set; u++, chunk_rec.offset[0] += idx_info->layout->u.chunk.dim[0]) {
+            haddr_t addr;       /* Chunk address */
+
+            /* Get the address of the chunk for the index */
+            if(H5EA_get(ea, idx_info->dxpl_id, u, &addr) < 0)
+                HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get chunk address")
+
+            /* Check if chunk exists */
+            if(H5F_addr_defined(addr)) {
+                /* Set chunk address for callback record */
+                chunk_rec.chunk_addr = addr;
+
+                /* Make chunk callback */
+                if((ret_value = (*chunk_cb)(&chunk_rec, chunk_udata)) < 0)
+                    HERROR(H5E_DATASET, H5E_CALLBACK, "failure in generic chunk iterator callback");
+            } /* end if */
+        } /* end for */
+    } /* end if */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5D_earray_idx_iterate() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5D_earray_idx_remove
+ *
+ * Purpose:	Remove chunk from index.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *              Thursday, January 29, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5D_earray_idx_remove(const H5D_chk_idx_info_t *idx_info, H5D_chunk_common_ud_t *udata)
+{
+    H5EA_t      *ea;                    /* Pointer to extensible array structure */
+    haddr_t     addr = HADDR_UNDEF;     /* Chunk address */
+    hsize_t     idx;                    /* Array index of chunk */
+    herr_t	ret_value = SUCCEED;	/* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5D_earray_idx_remove)
+
+    HDassert(idx_info);
+    HDassert(idx_info->f);
+    HDassert(idx_info->layout);
+    HDassert(H5F_addr_defined(idx_info->layout->u.chunk.u.earray.addr));
+    HDassert(udata);
+
+    /* Check if the extensible array is open yet */
+    if(NULL == idx_info->layout->u.chunk.u.earray.ea) {
+        /* Open the extensible array in file */
+        if(H5D_earray_idx_open(idx_info) < 0)
+            HGOTO_ERROR(H5E_DATASET, H5E_CANTOPENOBJ, FAIL, "can't open extensible array")
+    } /* end if */
+
+    /* Set convenience pointer to extensible array structure */
+    ea = idx_info->layout->u.chunk.u.earray.ea;
+
+    /* Compute array index for chunk offset */
+    idx = udata->offset[0] / idx_info->layout->u.chunk.dim[0];
+
+    /* Get the address of the chunk for the index */
+    if(H5EA_get(ea, idx_info->dxpl_id, idx, &addr) < 0)
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get chunk address")
+
+    /* Remove raw data chunk from file */
+    H5_CHECK_OVERFLOW(idx_info->layout->u.chunk.size, /*From: */uint32_t, /*To: */hsize_t);
+    if(H5MF_xfree(idx_info->f, H5FD_MEM_DRAW, idx_info->dxpl_id, addr, (hsize_t)idx_info->layout->u.chunk.size) < 0)
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "unable to free chunk")
+
+    /* Reset the address of the chunk for the index */
+    addr = HADDR_UNDEF;
+    if(H5EA_set(ea, idx_info->dxpl_id, idx, &addr) < 0)
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTSET, FAIL, "unable to reset chunk address")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5D_earray_idx_remove() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5D_earray_idx_delete_cb
+ *
+ * Purpose:	Delete space for chunk in file
+ *
+ * Return:	Success:	Non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Saturday, January 31, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static int
+H5D_earray_idx_delete_cb(const H5D_chunk_rec_t *chunk_rec, void *_udata)
+{
+    H5D_earray_ud_t *udata = (H5D_earray_ud_t *)_udata;         /* User data for callback */
+    int ret_value = H5_ITER_CONT;       /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5D_earray_idx_delete_cb)
+
+    /* Sanity checks */
+    HDassert(chunk_rec);
+    HDassert(H5F_addr_defined(chunk_rec->chunk_addr));
+    HDassert(chunk_rec->nbytes > 0);
+    HDassert(udata);
+    HDassert(udata->f);
+
+    /* Remove raw data chunk from file */
+    H5_CHECK_OVERFLOW(chunk_rec->nbytes, /*From: */uint32_t, /*To: */hsize_t);
+    if(H5MF_xfree(udata->f, H5FD_MEM_DRAW, udata->dxpl_id, chunk_rec->chunk_addr, (hsize_t)chunk_rec->nbytes) < 0)
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTFREE, H5_ITER_ERROR, "unable to free chunk")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5D_earray_idx_delete_cb() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5D_earray_idx_delete
+ *
+ * Purpose:	Delete index and raw data storage for entire dataset
+ *              (i.e. all chunks)
+ *
+ * Note:	This implementation is slow, particularly for sparse
+ *              extensible arrays, replace it with call to H5EA_iterate()
+ *              when that's available.
+ *
+ * Return:	Success:	Non-negative
+ *		Failure:	negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Thursday, January 29, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5D_earray_idx_delete(const H5D_chk_idx_info_t *idx_info)
+{
+    herr_t ret_value = SUCCEED;     /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5D_earray_idx_delete)
+
+    /* Sanity checks */
+    HDassert(idx_info);
+    HDassert(idx_info->f);
+    HDassert(idx_info->layout);
+
+    /* Check if the index data structure has been allocated */
+    if(H5F_addr_defined(idx_info->layout->u.chunk.u.earray.addr)) {
+        H5D_earray_ud_t udata;         /* User data for callback */
+
+        /* Initialize user data for callback */
+        udata.f = idx_info->f;
+        udata.dxpl_id = idx_info->dxpl_id;
+
+        /* Iterate over the chunk addresses in the extensible array, deleting each chunk */
+        if(H5D_earray_idx_iterate(idx_info, H5D_earray_idx_delete_cb, &udata) < 0)
+            HGOTO_ERROR(H5E_DATASET, H5E_BADITER, FAIL, "unable to iterate over chunk addresses")
+
+        /* Close extensible array */
+        if(H5EA_close(idx_info->layout->u.chunk.u.earray.ea, idx_info->dxpl_id) < 0)
+            HGOTO_ERROR(H5E_DATASET, H5E_CANTCLOSEOBJ, FAIL, "unable to close extensible array")
+        idx_info->layout->u.chunk.u.earray.ea = NULL;
+
+        /* Delete extensible array */
+        if(H5EA_delete(idx_info->f, idx_info->dxpl_id, idx_info->layout->u.chunk.u.earray.addr) < 0)
+            HGOTO_ERROR(H5E_DATASET, H5E_CANTDELETE, FAIL, "unable to delete chunk extensible array")
+        idx_info->layout->u.chunk.u.earray.addr = HADDR_UNDEF;
+    } /* end if */
+    else
+        HDassert(NULL == idx_info->layout->u.chunk.u.earray.ea);
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5D_earray_idx_delete() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5D_earray_idx_copy_setup
+ *
+ * Purpose:	Set up any necessary information for copying chunks
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *              Saturday, January 31, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5D_earray_idx_copy_setup(const H5D_chk_idx_info_t *idx_info_src,
+    const H5D_chk_idx_info_t *idx_info_dst)
+{
+    H5EA_t      *ea_src;                    /* Pointer to extensible array structure */
+    herr_t      ret_value = SUCCEED;        /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5D_earray_idx_copy_setup)
+
+    HDassert(idx_info_src);
+    HDassert(idx_info_src->f);
+    HDassert(idx_info_src->layout);
+    HDassert(idx_info_dst);
+    HDassert(idx_info_dst->f);
+    HDassert(idx_info_dst->layout);
+    HDassert(!H5F_addr_defined(idx_info_dst->layout->u.chunk.u.earray.addr));
+
+    /* Check if the source extensible array is open yet */
+    if(NULL == idx_info_src->layout->u.chunk.u.earray.ea) {
+        /* Open the extensible array in file */
+        if(H5D_earray_idx_open(idx_info_src) < 0)
+            HGOTO_ERROR(H5E_DATASET, H5E_CANTOPENOBJ, FAIL, "can't open extensible array")
+    } /* end if */
+
+    /* Set convenience pointer to extensible array structure */
+    ea_src = idx_info_src->layout->u.chunk.u.earray.ea;
+
+    /* Create the extensible array that describes chunked storage in the dest. file */
+    if(H5D_earray_idx_create(idx_info_dst) < 0)
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to initialize chunked storage")
+    HDassert(H5F_addr_defined(idx_info_dst->layout->u.chunk.u.earray.addr));
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5D_earray_idx_copy_setup() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5D_earray_idx_copy_shutdown
+ *
+ * Purpose:	Shutdown any information from copying chunks
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *              Saturday, January 31, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5D_earray_idx_copy_shutdown(H5O_layout_t *layout_src, H5O_layout_t *layout_dst,
+    hid_t dxpl_id)
+{
+    herr_t      ret_value = SUCCEED;       /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5D_earray_idx_copy_shutdown)
+
+    HDassert(layout_src);
+    HDassert(layout_src->u.chunk.u.earray.ea);
+    HDassert(layout_dst);
+    HDassert(layout_dst->u.chunk.u.earray.ea);
+
+    /* Close extensible arrays */
+    if(H5EA_close(layout_src->u.chunk.u.earray.ea, dxpl_id) < 0)
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTCLOSEOBJ, FAIL, "unable to close extensible array")
+    layout_src->u.chunk.u.earray.ea = NULL;
+    if(H5EA_close(layout_dst->u.chunk.u.earray.ea, dxpl_id) < 0)
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTCLOSEOBJ, FAIL, "unable to close extensible array")
+    layout_dst->u.chunk.u.earray.ea = NULL;
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5D_earray_idx_copy_shutdown() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5D_earray_idx_size
+ *
+ * Purpose:     Retrieve the amount of index storage for chunked dataset
+ *
+ * Return:      Success:        Non-negative
+ *              Failure:        negative
+ *
+ * Programmer:  Quincey Koziol
+ *              Saturday, January 31, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5D_earray_idx_size(const H5D_chk_idx_info_t *idx_info, hsize_t *index_size)
+{
+    H5EA_t      *ea;                    /* Pointer to extensible array structure */
+    H5EA_stat_t ea_stat;                /* Extensible array statistics */
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI(H5D_earray_idx_size, FAIL)
+
+    /* Check args */
+    HDassert(idx_info);
+    HDassert(idx_info->f);
+    HDassert(idx_info->layout);
+    HDassert(H5F_addr_defined(idx_info->layout->u.chunk.u.earray.addr));
+    HDassert(index_size);
+
+    /* Open the extensible array in file */
+    if(H5D_earray_idx_open(idx_info) < 0)
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTOPENOBJ, FAIL, "can't open extensible array")
+
+    /* Set convenience pointer to extensible array structure */
+    ea = idx_info->layout->u.chunk.u.earray.ea;
+
+    /* Get the extensible array statistics */
+    if(H5EA_get_stats(ea, &ea_stat) < 0)
+	HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't query extensible array statistics")
+
+    /* Set the size of the extensible array */
+    *index_size = ea_stat.hdr_size + ea_stat.index_blk_size
+            + ea_stat.super_blk_size + ea_stat.data_blk_size;
+
+done:
+    if(idx_info->layout->u.chunk.u.earray.ea) {
+        if(H5EA_close(idx_info->layout->u.chunk.u.earray.ea, idx_info->dxpl_id) < 0)
+            HGOTO_ERROR(H5E_DATASET, H5E_CANTCLOSEOBJ, FAIL, "unable to close extensible array")
+        idx_info->layout->u.chunk.u.earray.ea = NULL;
+    } /* end if */
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5D_earray_idx_size() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5D_earray_idx_reset
+ *
+ * Purpose:	Reset indexing information.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *              Saturday, January 31, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5D_earray_idx_reset(H5O_layout_t *layout)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5D_earray_idx_reset)
+
+    HDassert(layout);
+
+    /* Reset index info */
+    layout->u.chunk.u.earray.addr = HADDR_UNDEF;
+    layout->u.chunk.u.earray.ea = NULL;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5D_earray_idx_reset() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5D_earray_idx_dump
+ *
+ * Purpose:	Dump indexing information to a stream.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *              Saturday, January 31, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5D_earray_idx_dump(const H5D_chk_idx_info_t *idx_info, FILE *stream)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5D_earray_idx_dump)
+
+    HDassert(idx_info);
+    HDassert(idx_info->f);
+    HDassert(idx_info->layout);
+    HDassert(stream);
+
+    HDfprintf(stream, "    Address: %a\n", idx_info->layout->u.chunk.u.earray.addr);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5D_earray_idx_dump() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5D_earray_idx_dest
+ *
+ * Purpose:	Release indexing information in memory.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *              Saturday, January 31, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5D_earray_idx_dest(const H5D_chk_idx_info_t *idx_info)
+{
+    herr_t      ret_value = SUCCEED;       /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5D_earray_idx_dest)
+
+    HDassert(idx_info);
+    HDassert(idx_info->f);
+    HDassert(idx_info->layout);
+
+    /* Check if the extensible array is open */
+    if(idx_info->layout->u.chunk.u.earray.ea) {
+        if(H5EA_close(idx_info->layout->u.chunk.u.earray.ea, idx_info->dxpl_id) < 0)
+            HGOTO_ERROR(H5E_DATASET, H5E_CANTCLOSEOBJ, FAIL, "unable to close extensible array")
+        idx_info->layout->u.chunk.u.earray.ea = NULL;
+    } /* end if */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5D_earray_idx_dest() */
+
diff --git a/src/H5Dint.c b/src/H5Dint.c
index 0e71ef8..f8ffeab 100644
--- a/src/H5Dint.c
+++ b/src/H5Dint.c
@@ -720,8 +720,19 @@ H5D_set_io_ops(H5D_t *dataset)
             dataset->shared->layout.ops = H5D_LOPS_CHUNK;
 
             /* Set the chunk operations */
-            /* (Only "B-tree" indexing type currently supported */
-            dataset->shared->layout.u.chunk.ops = H5D_COPS_BTREE;
+            switch(dataset->shared->layout.u.chunk.idx_type) {
+                case H5D_CHUNK_BTREE:
+                    dataset->shared->layout.u.chunk.ops = H5D_COPS_BTREE;
+                    break;
+
+                case H5D_CHUNK_EARRAY:
+                    dataset->shared->layout.u.chunk.ops = H5D_COPS_EARRAY;
+                    break;
+
+                default:
+                    HDassert(0 && "Unknown chunk index method!");
+                    HGOTO_ERROR(H5E_DATASET, H5E_UNSUPPORTED, FAIL, "unknown chunk index method")
+            } /* end switch */
             break;
 
         case H5D_COMPACT:
@@ -1121,6 +1132,10 @@ H5D_create(H5F_t *file, hid_t type_id, const H5S_t *space, hid_t dcpl_id,
         /* Set the latest version for the fill value message */
         if(H5O_fill_set_latest_version(&new_dset->shared->dcpl_cache.fill) < 0)
             HGOTO_ERROR(H5E_DATASET, H5E_CANTSET, NULL, "can't set latest version of fill value")
+
+        /* Set the latest version for the layout message */
+        if(H5O_layout_set_latest_version(&new_dset->shared->layout, new_dset->shared->space) < 0)
+            HGOTO_ERROR(H5E_DATASET, H5E_CANTSET, NULL, "can't set latest version of layout")
     } /* end if */
 
     /* Check if this dataset is going into a parallel file and set space allocation time */
@@ -2300,11 +2315,11 @@ H5D_set_extent(H5D_t *dset, const hsize_t *size, hid_t dxpl_id)
 
     /* Check if we are shrinking or expanding any of the dimensions */
     if((rank = H5S_get_simple_extent_dims(space, curr_dims, NULL)) < 0)
-    HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get dataset dimensions")
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get dataset dimensions")
 
     /* Modify the size of the data space */
     if((changed = H5S_set_extent(space, size)) < 0)
-    HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to modify size of data space")
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to modify size of data space")
 
     /* Don't bother updating things, unless they've changed */
     if(changed) {
diff --git a/src/H5Dpkg.h b/src/H5Dpkg.h
index 4bf4e75..0d8ca8c 100644
--- a/src/H5Dpkg.h
+++ b/src/H5Dpkg.h
@@ -277,7 +277,7 @@ typedef herr_t (*H5D_chunk_delete_func_t)(const H5D_chk_idx_info_t *idx_info);
 typedef herr_t (*H5D_chunk_copy_setup_func_t)(const H5D_chk_idx_info_t *idx_info_src,
     const H5D_chk_idx_info_t *idx_info_dst);
 typedef herr_t (*H5D_chunk_copy_shutdown_func_t)(H5O_layout_t *layout_src,
-    H5O_layout_t *layout_dst);
+    H5O_layout_t *layout_dst, hid_t dxpl_id);
 typedef herr_t (*H5D_chunk_size_func_t)(const H5D_chk_idx_info_t *idx_info,
     hsize_t *idx_size);
 typedef herr_t (*H5D_chunk_reset_func_t)(H5O_layout_t *layout);
@@ -506,6 +506,7 @@ H5_DLLVAR const H5D_layout_ops_t H5D_LOPS_CHUNK[1];
 
 /* Chunked layout operations */
 H5_DLLVAR const H5D_chunk_ops_t H5D_COPS_BTREE[1];
+H5_DLLVAR const H5D_chunk_ops_t H5D_COPS_EARRAY[1];
 
 
 /******************************/
diff --git a/src/H5Dpublic.h b/src/H5Dpublic.h
index bae5dcf..136911f 100644
--- a/src/H5Dpublic.h
+++ b/src/H5Dpublic.h
@@ -50,7 +50,8 @@ typedef enum H5D_layout_t {
 
 /* Types of chunk index data structures */
 typedef enum H5D_chunk_index_t {
-    H5D_CHUNK_BTREE	= 0,	/* v1 B-tree index			     */
+    H5D_CHUNK_BTREE	= 0,	/* v1 B-tree index (default)		     */
+    H5D_CHUNK_EARRAY            /* Extensible array (for 1-D unlimited dim)  */
 } H5D_chunk_index_t;
 
 /* Values for the space allocation time property */
diff --git a/src/H5EAprivate.h b/src/H5EAprivate.h
index f44d046..fcfccd0 100644
--- a/src/H5EAprivate.h
+++ b/src/H5EAprivate.h
@@ -48,7 +48,9 @@
 
 /* Extensible array class IDs */
 typedef enum H5EA_cls_id_t {
-    /* Start real class IDs at 0 -QAK */
+    H5EA_CLS_CHUNK_ID = 0,      /* Extensible array is for indexing dataset chunks */
+
+    /* (keep these last) */
     H5EA_CLS_TEST_ID,	        /* Extensible array is for testing (do not use for actual data) */
     H5EA_NUM_CLS_ID             /* Number of Extensible Array class IDs (must be last) */
 } H5EA_cls_id_t;
diff --git a/src/H5EAtest.c b/src/H5EAtest.c
index 31dfb5f..de63d11 100644
--- a/src/H5EAtest.c
+++ b/src/H5EAtest.c
@@ -50,6 +50,7 @@
 /* Sanity checking value for callback contexts */
 #define H5EA__TEST_BOGUS_VAL    42
 
+
 /******************/
 /* Local Typedefs */
 /******************/
@@ -59,6 +60,7 @@ typedef struct H5EA__test_ctx_t {
     uint32_t    bogus;          /* Placeholder field to verify that context is working */
 } H5EA__test_ctx_t;
 
+
 /********************/
 /* Package Typedefs */
 /********************/
diff --git a/src/H5Olayout.c b/src/H5Olayout.c
index a23e3ef..f2bfab0 100644
--- a/src/H5Olayout.c
+++ b/src/H5Olayout.c
@@ -30,6 +30,7 @@
 #include "H5MMprivate.h"	/* Memory management			*/
 #include "H5Opkg.h"             /* Object headers			*/
 #include "H5Pprivate.h"		/* Property lists			*/
+#include "H5Sprivate.h"		/* Dataspaces				*/
 
 
 /* PRIVATE PROTOTYPES */
@@ -111,7 +112,7 @@ H5O_layout_decode(H5F_t *f, hid_t UNUSED dxpl_id, unsigned UNUSED mesg_flags,
         HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
 
     mesg->version = *p++;
-    if(mesg->version < H5O_LAYOUT_VERSION_1 || mesg->version > H5O_LAYOUT_VERSION_3)
+    if(mesg->version < H5O_LAYOUT_VERSION_1 || mesg->version > H5O_LAYOUT_VERSION_4)
         HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, NULL, "bad version number for layout message")
 
     if(mesg->version < H5O_LAYOUT_VERSION_3) {
@@ -213,26 +214,68 @@ H5O_layout_decode(H5F_t *f, hid_t UNUSED dxpl_id, unsigned UNUSED mesg_flags,
                 break;
 
             case H5D_CHUNKED:
-                /* Dimensionality */
-                mesg->u.chunk.ndims = *p++;
-                if(mesg->u.chunk.ndims > H5O_LAYOUT_NDIMS)
-                    HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, NULL, "dimensionality is too large")
-
-                /* B-tree address */
-                H5F_addr_decode(f, &p, &(mesg->u.chunk.u.btree.addr));
-
-                /* Chunk dimensions */
-                for(u = 0; u < mesg->u.chunk.ndims; u++)
-                    UINT32DECODE(p, mesg->u.chunk.dim[u]);
-
-                /* Compute chunk size */
-                for(u = 1, mesg->u.chunk.size = mesg->u.chunk.dim[0]; u < mesg->u.chunk.ndims; u++)
-                    mesg->u.chunk.size *= mesg->u.chunk.dim[u];
-
-                /* Set the chunk operations */
-                /* (Only "btree" indexing type supported with v3 of message format) */
-                mesg->u.chunk.idx_type = H5D_CHUNK_BTREE;
-                mesg->u.chunk.ops = H5D_COPS_BTREE;
+                if(mesg->version < H5O_LAYOUT_VERSION_4) {
+                    /* Dimensionality */
+                    mesg->u.chunk.ndims = *p++;
+                    if(mesg->u.chunk.ndims > H5O_LAYOUT_NDIMS)
+                        HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, NULL, "dimensionality is too large")
+
+                    /* B-tree address */
+                    H5F_addr_decode(f, &p, &(mesg->u.chunk.u.btree.addr));
+
+                    /* Chunk dimensions */
+                    for(u = 0; u < mesg->u.chunk.ndims; u++)
+                        UINT32DECODE(p, mesg->u.chunk.dim[u]);
+
+                    /* Compute chunk size */
+                    for(u = 1, mesg->u.chunk.size = mesg->u.chunk.dim[0]; u < mesg->u.chunk.ndims; u++)
+                        mesg->u.chunk.size *= mesg->u.chunk.dim[u];
+
+                    /* Set the chunk operations */
+                    /* (Only "btree" indexing type supported with v3 of message format) */
+                    mesg->u.chunk.idx_type = H5D_CHUNK_BTREE;
+                    mesg->u.chunk.ops = H5D_COPS_BTREE;
+                } /* end if */
+                else {
+                    /* Dimensionality */
+                    mesg->u.chunk.ndims = *p++;
+                    if(mesg->u.chunk.ndims > H5O_LAYOUT_NDIMS)
+                        HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, NULL, "dimensionality is too large")
+
+                    /* Chunk dimensions */
+                    for(u = 0; u < mesg->u.chunk.ndims; u++)
+                        UINT32DECODE(p, mesg->u.chunk.dim[u]);
+
+                    /* Compute chunk size */
+                    for(u = 1, mesg->u.chunk.size = mesg->u.chunk.dim[0]; u < mesg->u.chunk.ndims; u++)
+                        mesg->u.chunk.size *= mesg->u.chunk.dim[u];
+
+                    /* Chunk index type */
+                    mesg->u.chunk.idx_type = *p++;
+                    if(mesg->u.chunk.idx_type > H5D_CHUNK_EARRAY)
+                        HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, NULL, "unknown chunk index type")
+
+                    switch(mesg->u.chunk.idx_type) {
+                        case H5D_CHUNK_BTREE:
+                            /* B-tree address */
+                            H5F_addr_decode(f, &p, &(mesg->u.chunk.u.btree.addr));
+
+                            /* Set the chunk operations */
+                            mesg->u.chunk.ops = H5D_COPS_BTREE;
+                            break;
+
+                        case H5D_CHUNK_EARRAY:
+                            /* Extensible array address */
+                            H5F_addr_decode(f, &p, &(mesg->u.chunk.u.earray.addr));
+
+                            /* Set the chunk operations */
+                            mesg->u.chunk.ops = H5D_COPS_EARRAY;
+                            break;
+
+                        default:
+                            HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, NULL, "Invalid chunk index type")
+                    } /* end switch */
+                } /* end else */
 
                 /* Set the layout operations */
                 mesg->ops = H5D_LOPS_CHUNK;
@@ -327,16 +370,45 @@ H5O_layout_encode(H5F_t *f, hbool_t UNUSED disable_shared, uint8_t *p, const voi
             break;
 
         case H5D_CHUNKED:
-            /* Number of dimensions */
-            HDassert(mesg->u.chunk.ndims > 0 && mesg->u.chunk.ndims <= H5O_LAYOUT_NDIMS);
-            *p++ = (uint8_t)mesg->u.chunk.ndims;
+            if(mesg->version < H5O_LAYOUT_VERSION_4) {
+                /* Number of dimensions */
+                HDassert(mesg->u.chunk.ndims > 0 && mesg->u.chunk.ndims <= H5O_LAYOUT_NDIMS);
+                *p++ = (uint8_t)mesg->u.chunk.ndims;
 
-            /* B-tree address */
-            H5F_addr_encode(f, &p, mesg->u.chunk.u.btree.addr);
+                /* B-tree address */
+                H5F_addr_encode(f, &p, mesg->u.chunk.u.btree.addr);
 
-            /* Dimension sizes */
-            for(u = 0; u < mesg->u.chunk.ndims; u++)
-                UINT32ENCODE(p, mesg->u.chunk.dim[u]);
+                /* Dimension sizes */
+                for(u = 0; u < mesg->u.chunk.ndims; u++)
+                    UINT32ENCODE(p, mesg->u.chunk.dim[u]);
+            } /* end if */
+            else {
+                /* Number of dimensions */
+                HDassert(mesg->u.chunk.ndims > 0 && mesg->u.chunk.ndims <= H5O_LAYOUT_NDIMS);
+                *p++ = (uint8_t)mesg->u.chunk.ndims;
+
+                /* Dimension sizes */
+                for(u = 0; u < mesg->u.chunk.ndims; u++)
+                    UINT32ENCODE(p, mesg->u.chunk.dim[u]);
+
+                /* Chunk index type */
+                *p++ = (uint8_t)mesg->u.chunk.idx_type;
+
+                switch(mesg->u.chunk.idx_type) {
+                    case H5D_CHUNK_BTREE:
+                        /* B-tree address */
+                        H5F_addr_encode(f, &p, mesg->u.chunk.u.btree.addr);
+                        break;
+
+                    case H5D_CHUNK_EARRAY:
+                        /* Extensible array address */
+                        H5F_addr_encode(f, &p, mesg->u.chunk.u.earray.addr);
+                        break;
+
+                    default:
+                        HGOTO_ERROR(H5E_OHDR, H5E_CANTENCODE, FAIL, "Invalid chunk index type")
+                } /* end switch */
+            } /* end else */
             break;
 
         default:
@@ -709,6 +781,13 @@ H5O_layout_debug(H5F_t UNUSED *f, hid_t UNUSED dxpl_id, const void *_mesg,
                               "B-tree address:", mesg->u.chunk.u.btree.addr);
                     break;
 
+                case H5D_CHUNK_EARRAY:
+                    HDfprintf(stream, "%*s%-*s %s\n", indent, "", fwidth,
+                              "Index Type:", "Extensible Array");
+                    HDfprintf(stream, "%*s%-*s %a\n", indent, "", fwidth,
+                              "Extensible Array address:", mesg->u.chunk.u.earray.addr);
+                    break;
+
                 default:
                     HDfprintf(stream, "%*s%-*s %s (%u)\n", indent, "", fwidth,
                               "Index Type:", "Unknown", (unsigned)mesg->u.chunk.idx_type);
@@ -792,8 +871,29 @@ H5O_layout_meta_size(const H5F_t *f, const void *_mesg)
             /* Dimension sizes */
             ret_value += mesg->u.chunk.ndims * 4;
 
-            /* B-tree address */
-            ret_value += H5F_SIZEOF_ADDR(f);    /* Address of data */
+            if(mesg->version < H5O_LAYOUT_VERSION_4) {
+                /* B-tree address */
+                ret_value += H5F_SIZEOF_ADDR(f);    /* Address of data */
+            } /* end if */
+            else {
+                /* Type of chunk index */
+                ret_value++;
+
+                switch(mesg->u.chunk.idx_type) {
+                    case H5D_CHUNK_BTREE:
+                        /* B-tree address */
+                        ret_value += H5F_SIZEOF_ADDR(f);    /* Address of data */
+                        break;
+
+                    case H5D_CHUNK_EARRAY:
+                        /* Extensible Array address */
+                        ret_value += H5F_SIZEOF_ADDR(f);    /* Address of data */
+                        break;
+
+                    default:
+                        HGOTO_ERROR(H5E_OHDR, H5E_CANTENCODE, 0, "Invalid chunk index type")
+                } /* end switch */
+            } /* end else */
             break;
 
         default:
@@ -804,3 +904,66 @@ done:
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5O_layout_meta_size() */
 
+
+/*-------------------------------------------------------------------------
+ * Function:    H5O_layout_set_latest_version
+ *
+ * Purpose:     Set the encoding for a layout to the latest version.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:  Quincey Koziol
+ *              Thursday, January 15, 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_layout_set_latest_version(H5O_layout_t *layout, const H5S_t *space)
+{
+    int sndims;                         /* Rank of dataspace */
+    unsigned ndims;                     /* Rank of dataspace */
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI(H5O_layout_set_latest_version, FAIL)
+
+    /* Sanity check */
+    HDassert(layout);
+
+    /* Set encoding of layout to latest version */
+    layout->version = H5O_LAYOUT_VERSION_LATEST;
+
+    /* Query the dimensionality of the dataspace */
+    if((sndims = H5S_GET_EXTENT_NDIMS(space)) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "invalid dataspace rank")
+    ndims = (unsigned)sndims;
+
+    /* Avoid scalar/null dataspace */
+    if(ndims > 0) {
+        hsize_t max_dims[H5O_LAYOUT_NDIMS];     /* Current dimension sizes */
+        unsigned unlim_count;           /* Count of unlimited max. dimensions */
+        unsigned u;                     /* Local index variable */
+
+        /* Query the dataspace's dimensions */
+        if(H5S_get_simple_extent_dims(space, NULL, max_dims) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "can't get dataspace max. dimensions")
+
+        /* Spin through the max. dimensions, looking for unlimited dimensions */
+        unlim_count = 0;
+        for(u = 0; u < ndims; u++)
+            if(max_dims[u] == H5S_UNLIMITED)
+                unlim_count++;
+
+        /* If we have only 1 unlimited dimension, we can use extensible array index */
+        if(1 == unlim_count) {
+            /* Check for rank == 1 (>1 unsupported currently) */
+            if(1 == ndims) {
+                /* Set the chunk index type */
+                layout->u.chunk.idx_type = H5D_CHUNK_EARRAY;
+            } /* end if */
+        } /* end if */
+    } /* end if */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_layout_set_latest_version() */
+
diff --git a/src/H5Oprivate.h b/src/H5Oprivate.h
index cc88bdc..3a00491 100644
--- a/src/H5Oprivate.h
+++ b/src/H5Oprivate.h
@@ -361,6 +361,14 @@ typedef struct H5O_layout_chunk_btree_t {
     H5RC_t     *shared;			/* Ref-counted shared info for B-tree nodes */
 } H5O_layout_chunk_btree_t;
 
+/* Forward declaration of structs used below */
+struct H5EA_t;                          /* Defined in H5EAprivate.h          */
+
+typedef struct H5O_layout_chunk_earray_t {
+    haddr_t	addr;			/* File address of extensible array  */
+    struct H5EA_t *ea;                  /* Pointer to extensible array struct */
+} H5O_layout_chunk_earray_t;
+
 typedef struct H5O_layout_chunk_t {
     H5D_chunk_index_t idx_type;		/* Type of chunk index               */
     unsigned	ndims;			/* Num dimensions in chunk           */
@@ -369,6 +377,7 @@ typedef struct H5O_layout_chunk_t {
     const struct H5D_chunk_ops_t *ops;  /* Pointer to chunked layout operations */
     union {
         H5O_layout_chunk_btree_t btree; /* Information for v1 B-tree index   */
+        H5O_layout_chunk_earray_t earray; /* Information for extensible array index */
     } u;
 } H5O_layout_chunk_t;
 
@@ -566,6 +575,7 @@ typedef struct {
 
 /* Forward declarations for prototype arguments */
 struct H5P_genplist_t;
+struct H5S_t;
 
 /* Object header routines */
 H5_DLL herr_t H5O_init(void);
@@ -656,6 +666,8 @@ H5_DLL herr_t H5O_loc_free(H5O_loc_t *loc);
 
 /* Layout operators */
 H5_DLL size_t H5O_layout_meta_size(const H5F_t *f, const void *_mesg);
+H5_DLL herr_t H5O_layout_set_latest_version(H5O_layout_t *layout,
+    const struct H5S_t *space);
 
 /* EFL operators */
 H5_DLL hsize_t H5O_efl_total_size(H5O_efl_t *efl);
diff --git a/src/Makefile.am b/src/Makefile.am
index 9ae2252..b2b0a98 100755
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -47,8 +47,7 @@ libhdf5_la_SOURCES= H5.c H5checksum.c H5dbg.c H5system.c H5timer.c H5trace.c \
         H5B2.c H5B2cache.c H5B2dbg.c H5B2int.c H5B2stat.c H5B2test.c \
         H5C.c H5CS.c \
         H5D.c H5Dbtree.c H5Dchunk.c H5Dcompact.c H5Dcontig.c H5Ddbg.c \
-        H5Ddeprec.c H5Defl.c H5Dfill.c H5Dint.c \
-        H5Dio.c \
+        H5Ddeprec.c H5Dearray.c H5Defl.c H5Dfill.c H5Dint.c H5Dio.c \
         H5Dmpio.c H5Doh.c H5Dscatgath.c H5Dselect.c H5Dtest.c \
         H5E.c H5Edeprec.c H5Eint.c \
         H5EA.c H5EAcache.c H5EAdbg.c H5EAdblkpage.c H5EAdblock.c H5EAhdr.c \
diff --git a/src/Makefile.in b/src/Makefile.in
index 0a08832..6638703 100644
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -84,7 +84,7 @@ am_libhdf5_la_OBJECTS = H5.lo H5checksum.lo H5dbg.lo H5system.lo \
 	H5Bdbg.lo H5B2.lo H5B2cache.lo H5B2dbg.lo H5B2int.lo \
 	H5B2stat.lo H5B2test.lo H5C.lo H5CS.lo H5D.lo H5Dbtree.lo \
 	H5Dchunk.lo H5Dcompact.lo H5Dcontig.lo H5Ddbg.lo H5Ddeprec.lo \
-	H5Defl.lo H5Dfill.lo H5Dint.lo H5Dio.lo H5Dmpio.lo H5Doh.lo \
+	H5Dearray.lo H5Defl.lo H5Dfill.lo H5Dint.lo H5Dio.lo H5Dmpio.lo H5Doh.lo \
 	H5Dscatgath.lo H5Dselect.lo H5Dtest.lo H5E.lo H5Edeprec.lo \
 	H5Eint.lo H5EA.lo H5EAcache.lo H5EAdbg.lo H5EAdblkpage.lo \
 	H5EAdblock.lo H5EAhdr.lo H5EAiblock.lo H5EAint.lo \
@@ -430,7 +430,7 @@ libhdf5_la_SOURCES = H5.c H5checksum.c H5dbg.c H5system.c H5timer.c H5trace.c \
         H5B2.c H5B2cache.c H5B2dbg.c H5B2int.c H5B2stat.c H5B2test.c \
         H5C.c H5CS.c \
         H5D.c H5Dbtree.c H5Dchunk.c H5Dcompact.c H5Dcontig.c H5Ddbg.c \
-        H5Ddeprec.c H5Defl.c H5Dfill.c H5Dint.c \
+        H5Ddeprec.c H5Dearray.c H5Defl.c H5Dfill.c H5Dint.c \
         H5Dio.c \
         H5Dmpio.c H5Doh.c H5Dscatgath.c H5Dselect.c H5Dtest.c \
         H5E.c H5Edeprec.c H5Eint.c \
@@ -641,6 +641,7 @@ distclean-compile:
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Dcontig.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Ddbg.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Ddeprec.Plo@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Dearray.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Defl.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Dfill.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Dint.Plo@am__quote@