[svn-r27022] Add new functions H5Pset_virtual_dataspace_bounds and

H5Pget_virtual_dataspace_bounds.
Minor refactor of dataset initialization code to make this cleaner.
Update h5_vds-percival-unlim-maxmin.c
Other minor fixes/cleanup.

Tested: ummon

12 files changed, 283 insertions, 143 deletions

diff --git a/examples/h5_vds-percival-unlim-maxmin.c b/examples/h5_vds-percival-unlim-maxmin.c
index c89dbac..4640b94 100644
--- a/examples/h5_vds-percival-unlim-maxmin.c
+++ b/examples/h5_vds-percival-unlim-maxmin.c
@@ -209,18 +209,27 @@ main (void)
      * min extents depending on the sizes of the underlying datasets
      */
     dapl = H5Pcreate (H5P_DATASET_ACCESS);
-    //status = H5Pset_virtual_dataset_bounds (dapl, H5D_VDS_MAX);
-    //status = H5Pset_virtual_dataset_bounds (dapl, H5D_VDS_MIN);
-    vdset = H5Dopen (vfile, DATASET, dapl);
-
-    /* Let's get space of the VDS and its dimension; we should get 32(or 17)x10x10 */
-    vspace = H5Dget_space (vdset);
-    H5Sget_simple_extent_dims (vspace, vdsdims_out, vdsdims_max_out);
-    printf ("VDS dimensions: ");
-    for (i=0; i<RANK; i++)
-        printf (" %d ", (int)vdsdims_out[i]);
-    printf ("\n");
 
+    for(i = 0; i < 2; i++) {
+        status = H5Pset_virtual_dataspace_bounds (dapl, i ? H5D_VDS_MAX : H5D_VDS_MIN);
+        vdset = H5Dopen (vfile, DATASET, dapl);
+
+        /* Let's get space of the VDS and its dimension; we should get 32(or 20)x10x10 */
+        vspace = H5Dget_space (vdset);
+        H5Sget_simple_extent_dims (vspace, vdsdims_out, vdsdims_max_out);
+        printf ("VDS dimensions, bounds = H5D_VDS_M%s: ", i ? "AX" : "IN");
+        for (j=0; j<RANK; j++)
+            printf (" %d ", (int)vdsdims_out[j]);
+        printf ("\n");
+
+        /* Close */
+        status = H5Dclose (vdset);
+        status = H5Sclose (vspace);
+    }
+
+    status = H5Pclose (dapl);
+
+    vdset = H5Dopen (vfile, DATASET, H5P_DEFAULT);
 
     /*
      * Get creation property list and mapping properties.
diff --git a/src/H5Dint.c b/src/H5Dint.c
index 1757665..39b3eaf 100644
--- a/src/H5Dint.c
+++ b/src/H5Dint.c
@@ -1052,7 +1052,7 @@ H5D__create(H5F_t *file, hid_t type_id, const H5S_t *space, hid_t dcpl_id,
         HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, NULL, "unable to initialize I/O operations")
 
     /* Create the layout information for the new dataset */
-    if((new_dset->shared->layout.ops->construct)(file, new_dset) < 0)
+    if(new_dset->shared->layout.ops->construct && (new_dset->shared->layout.ops->construct)(file, new_dset) < 0)
         HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, NULL, "unable to construct layout information")
 
     /* Update the dataset's object header info. */
diff --git a/src/H5Dlayout.c b/src/H5Dlayout.c
index 87e1bc8..cb8b27d 100644
--- a/src/H5Dlayout.c
+++ b/src/H5Dlayout.c
@@ -391,85 +391,55 @@ H5D__layout_oh_read(H5D_t *dataset, hid_t dxpl_id, hid_t dapl_id, H5P_genplist_t
     if(H5D_CHUNKED == dataset->shared->layout.type)
         dataset->shared->layout.u.chunk.ndims++;
 
-    switch(dataset->shared->layout.type) {
-        case H5D_CONTIGUOUS:
-        {
-            hsize_t tmp_size;                   /* Temporary holder for raw data size */
-            size_t tmp_sieve_buf_size;          /* Temporary holder for sieve buffer size */
-
-            /* Compute the size of the contiguous storage for versions of the
-             * layout message less than version 3 because versions 1 & 2 would
-             * truncate the dimension sizes to 32-bits of information. - QAK 5/26/04
-             */
-            if(dataset->shared->layout.version < 3) {
-                hssize_t snelmts;                   /* Temporary holder for number of elements in dataspace */
-                hsize_t nelmts;                     /* Number of elements in dataspace */
-                size_t dt_size;                     /* Size of datatype */
-
-                /* Retrieve the number of elements in the dataspace */
-                if((snelmts = H5S_GET_EXTENT_NPOINTS(dataset->shared->space)) < 0)
-                    HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "unable to retrieve number of elements in dataspace")
-                nelmts = (hsize_t)snelmts;
-
-                /* Get the datatype's size */
-                if(0 == (dt_size = H5T_GET_SIZE(dataset->shared->type)))
-                    HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "unable to retrieve size of datatype")
-
-                /* Compute the size of the dataset's contiguous storage */
-                tmp_size = nelmts * dt_size;
-
-                /* Check for overflow during multiplication */
-                if(nelmts != (tmp_size / dt_size))
-                    HGOTO_ERROR(H5E_DATASET, H5E_OVERFLOW, FAIL, "size of dataset's storage overflowed")
-
-                /* Assign the dataset's contiguous storage size */
-                dataset->shared->layout.storage.u.contig.size = tmp_size;
-            } else
-                tmp_size = dataset->shared->layout.storage.u.contig.size;
-
-	    /* Get the sieve buffer size for the file */
-	    tmp_sieve_buf_size = H5F_SIEVE_BUF_SIZE(dataset->oloc.file);
-
-	    /* Adjust the sieve buffer size to the smaller one between the dataset size and the buffer size
-	     * from the file access property.  (SLU - 2012/3/30) */
-	    if(tmp_size < tmp_sieve_buf_size)
-		dataset->shared->cache.contig.sieve_buf_size = tmp_size;
-	    else
-		dataset->shared->cache.contig.sieve_buf_size = tmp_sieve_buf_size;
-        }
-            break;
-
-        case H5D_CHUNKED:
-            /* Initialize the chunk cache for the dataset */
-            if(H5D__chunk_init(dataset->oloc.file, dxpl_id, dataset, dapl_id) < 0)
-                HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "can't initialize chunk cache")
-            break;
-
-        case H5D_COMPACT:
-            break;
-
-        case H5D_VIRTUAL:
-            {
-                size_t i;
-
-                HDassert(dataset->shared->layout.storage.u.virt.list || (dataset->shared->layout.storage.u.virt.list_nused == 0));
-
-                /* Patch the virtual selection dataspaces if necessary */
-                for(i = 0; i < dataset->shared->layout.storage.u.virt.list_nused; i++) {
-                    if(dataset->shared->layout.storage.u.virt.list[i].virtual_space_status != H5O_VIRTUAL_STATUS_CORRECT) {
-                        if(H5S_extent_copy(dataset->shared->layout.storage.u.virt.list[i].virtual_select, dataset->shared->space) < 0)
-                            HGOTO_ERROR(H5E_DATASET, H5E_CANTCOPY, FAIL, "can't copy virtual dataspace extent")
-                        dataset->shared->layout.storage.u.virt.list[i].virtual_space_status = H5O_VIRTUAL_STATUS_CORRECT;
-                    } /* end if */
-                } /* end for */
-            } /* end block */
-            break;
+    if(H5D_CONTIGUOUS == dataset->shared->layout.type) {
+        hsize_t tmp_size;                   /* Temporary holder for raw data size */
+        size_t tmp_sieve_buf_size;          /* Temporary holder for sieve buffer size */
+
+        /* Compute the size of the contiguous storage for versions of the
+         * layout message less than version 3 because versions 1 & 2 would
+         * truncate the dimension sizes to 32-bits of information. - QAK 5/26/04
+         */
+        if(dataset->shared->layout.version < 3) {
+            hssize_t snelmts;                   /* Temporary holder for number of elements in dataspace */
+            hsize_t nelmts;                     /* Number of elements in dataspace */
+            size_t dt_size;                     /* Size of datatype */
+
+            /* Retrieve the number of elements in the dataspace */
+            if((snelmts = H5S_GET_EXTENT_NPOINTS(dataset->shared->space)) < 0)
+                HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "unable to retrieve number of elements in dataspace")
+            nelmts = (hsize_t)snelmts;
+
+            /* Get the datatype's size */
+            if(0 == (dt_size = H5T_GET_SIZE(dataset->shared->type)))
+                HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "unable to retrieve size of datatype")
+
+            /* Compute the size of the dataset's contiguous storage */
+            tmp_size = nelmts * dt_size;
+
+            /* Check for overflow during multiplication */
+            if(nelmts != (tmp_size / dt_size))
+                HGOTO_ERROR(H5E_DATASET, H5E_OVERFLOW, FAIL, "size of dataset's storage overflowed")
+
+            /* Assign the dataset's contiguous storage size */
+            dataset->shared->layout.storage.u.contig.size = tmp_size;
+        } /* end if */
+        else
+            tmp_size = dataset->shared->layout.storage.u.contig.size;
+
+        /* Get the sieve buffer size for the file */
+        tmp_sieve_buf_size = H5F_SIEVE_BUF_SIZE(dataset->oloc.file);
+
+        /* Adjust the sieve buffer size to the smaller one between the dataset size and the buffer size
+         * from the file access property.  (SLU - 2012/3/30) */
+        if(tmp_size < tmp_sieve_buf_size)
+            dataset->shared->cache.contig.sieve_buf_size = tmp_size;
+        else
+            dataset->shared->cache.contig.sieve_buf_size = tmp_sieve_buf_size;
+    } /* end if */
 
-        case H5D_LAYOUT_ERROR:
-        case H5D_NLAYOUTS:
-        default:
-            HGOTO_ERROR(H5E_DATASET, H5E_UNSUPPORTED, FAIL, "unknown storage method")
-    } /* end switch */ /*lint !e788 All appropriate cases are covered */
+    /* Initialize the layout information for the new dataset */
+    if(dataset->shared->layout.ops->init && (dataset->shared->layout.ops->init)(dataset->oloc.file, dxpl_id, dataset, dapl_id) < 0)
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to initialize layout information")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
diff --git a/src/H5Dpkg.h b/src/H5Dpkg.h
index 978936b..d3cea4c 100644
--- a/src/H5Dpkg.h
+++ b/src/H5Dpkg.h
@@ -666,6 +666,8 @@ H5_DLL herr_t H5D__virtual_copy(H5F_t *f_src,
     const H5O_storage_virtual_t *storage_src, H5F_t *f_dst,
     H5O_storage_virtual_t *storage_dst, H5T_t *dt_src, H5O_copy_t *cpy_info,
     hid_t dxpl_id);
+H5_DLL herr_t H5D__virtual_init(H5F_t *f, hid_t dxpl_id, const H5D_t *dset,
+    hid_t dapl_id);
 H5_DLL hbool_t H5D__virtual_is_space_alloc(const H5O_storage_t *storage);
 
 /* Functions that operate on EFL (External File List)*/
diff --git a/src/H5Dprivate.h b/src/H5Dprivate.h
index 5f588fd..a89f937 100644
--- a/src/H5Dprivate.h
+++ b/src/H5Dprivate.h
@@ -52,6 +52,7 @@
 #define H5D_ACS_DATA_CACHE_NUM_SLOTS_NAME   "rdcc_nslots"   /* Size of raw data chunk cache(slots) */
 #define H5D_ACS_DATA_CACHE_BYTE_SIZE_NAME   "rdcc_nbytes"   /* Size of raw data chunk cache(bytes) */
 #define H5D_ACS_PREEMPT_READ_CHUNKS_NAME    "rdcc_w0"       /* Preemption read chunks first */
+#define H5D_ACS_VDS_BOUNDS_NAME             "vds_bounds"    /* VDS bounds option */
 
 /* ======== Data transfer properties ======== */
 #define H5D_XFER_MAX_TEMP_BUF_NAME      "max_temp_buf"  /* Maximum temp buffer size */
diff --git a/src/H5Dpublic.h b/src/H5Dpublic.h
index a08ea3d..e4b1311 100644
--- a/src/H5Dpublic.h
+++ b/src/H5Dpublic.h
@@ -94,6 +94,13 @@ typedef enum H5D_fill_value_t {
     H5D_FILL_VALUE_USER_DEFINED =2
 } H5D_fill_value_t;
 
+/* Values for VDS bounds option */
+typedef enum H5D_vds_bounds_t {
+    H5D_VDS_ERROR       = -1,
+    H5D_VDS_MAX         = 0,
+    H5D_VDS_MIN         = 1
+} H5D_vds_bounds_t;
+
 /********************/
 /* Public Variables */
 /********************/
diff --git a/src/H5Dvirtual.c b/src/H5Dvirtual.c
index 40fe7ac..109078f 100644
--- a/src/H5Dvirtual.c
+++ b/src/H5Dvirtual.c
@@ -36,6 +36,7 @@
 #include "H5Fprivate.h"         /* Files                                */
 #include "H5Gprivate.h"         /* Groups                               */
 #include "H5HGprivate.h"        /* Global Heaps                         */
+#include "H5Iprivate.h"         /* IDs                                  */
 #include "H5MMprivate.h"        /* Memory management                    */
 #include "H5Oprivate.h"         /* Object headers                       */
 #include "H5Sprivate.h"         /* Dataspaces                           */
@@ -56,7 +57,6 @@
 /********************/
 
 /* Layout operation callbacks */
-static herr_t H5D__virtual_construct(H5F_t *f, H5D_t *dset);
 static herr_t H5D__virtual_io_init(const H5D_io_info_t *io_info,
     const H5D_type_info_t *type_info, hsize_t nelmts, const H5S_t *file_space,
     const H5S_t *mem_space, H5D_chunk_map_t *cm);
@@ -79,8 +79,8 @@ static herr_t H5D__virtual_open_source_dset(const H5D_t *vdset,
 
 /* Contiguous storage layout I/O ops */
 const H5D_layout_ops_t H5D_LOPS_VIRTUAL[1] = {{
-    H5D__virtual_construct,
     NULL,
+    H5D__virtual_init,
     H5D__virtual_is_space_alloc,
     H5D__virtual_io_init,
     H5D__virtual_read,
@@ -348,6 +348,7 @@ H5D__virtual_set_extent_unlim(const H5D_t *dset, hid_t dxpl_id)
     HDassert(dset);
     storage = &dset->shared->layout.storage.u.virt;
     HDassert(dset->shared->layout.storage.type == H5D_VIRTUAL);
+    HDassert((storage->bounds == H5D_VDS_MAX) || (storage->bounds == H5D_VDS_MIN));
 
     /* Get rank of VDS */
     if((rank = H5S_GET_EXTENT_NDIMS(dset->shared->space)) < 0)
@@ -383,7 +384,7 @@ H5D__virtual_set_extent_unlim(const H5D_t *dset, hid_t dxpl_id)
 
                 /* Check if we are setting extent by maximum or minimum of
                  * mappings */
-                if(storage->set_extent_max) {
+                if(storage->bounds == H5D_VDS_MAX) {
                     /* Check if the source extent in the unlimited dimension
                      * changed since the last time the VDS extent/mapping
                      * was updated */
@@ -427,7 +428,6 @@ H5D__virtual_set_extent_unlim(const H5D_t *dset, hid_t dxpl_id)
                         clip_size_incl_trail = storage->list[i].clip_size_virtual_incl_trail;
                     } //VDSINC
                     else {
-                        HDassert(0 && "Checking code coverage..."); //VDSINC
                         /* Get size that virtual selection would be clipped to
                          * to match size of source selection.  Also get the clip
                          * size including the trailing space (gap between
@@ -479,7 +479,7 @@ H5D__virtual_set_extent_unlim(const H5D_t *dset, hid_t dxpl_id)
 
     /* If we did not change the VDS dimensions and we are setting the extent by
      * maximum, there is nothing more to update */
-    if(changed || !storage->set_extent_max) {
+    if(changed || (storage->bounds == H5D_VDS_MIN)) {
         /* Update VDS extent */
         if(changed)
             if(H5S_set_extent(dset->shared->space, new_dims) < 0)
@@ -500,15 +500,13 @@ H5D__virtual_set_extent_unlim(const H5D_t *dset, hid_t dxpl_id)
                         HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to modify size of data space")
 
                 /* Check if we are setting extent by the minimum of mappings */
-                if(!storage->set_extent_max) {
+                if(storage->bounds == H5D_VDS_MIN) {
                     /* Clip virtual selection to extent (only necessary if the
                      * extent changed, otherwise it will already be clipped to
                      * the extent) */
-                    if(changed) {
-                        HDassert(0 && "Checking code coverage..."); //VDSINC
+                    if(changed)
                         if(H5S_hyper_clip_to_extent(storage->list[i].virtual_select))
                             HGOTO_ERROR(H5E_DATASET, H5E_CANTCLIP, FAIL, "failed to clip unlimited selection")
-                    } //VDSINC
 
                     /* Check if the virtual extent in the unlimited dimension
                      * changed since the last time the VDS extent/mapping was
@@ -520,7 +518,6 @@ H5D__virtual_set_extent_unlim(const H5D_t *dset, hid_t dxpl_id)
                         clip_size = storage->list[i].clip_size_source;
                     } //VDSINC
                     else {
-                        HDassert(0 && "Checking code coverage..."); //VDSINC
                         /* Get size that source selection will be clipped to to
                          * match size of virtual selection */
                         if(H5S_hyper_get_clip_extent(storage->list[i].source_select, storage->list[i].virtual_select, &clip_size, NULL) < 0)
@@ -638,38 +635,52 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:    H5D__virtual_construct
+ * Function:    H5D__virtual_init
  *
- * Purpose:     Constructs new virtual layout information for dataset
+ * Purpose:     Initialize the virtual layout information for a dataset.
+ *              This is called when the dataset is initialized.
  *
  * Return:      Non-negative on success/Negative on failure
  *
  * Programmer:  Neil Fortner
- *              Monday, February 2, 2015
+ *              Thursday, April 30, 2015
  *
  *-------------------------------------------------------------------------
  */
-static herr_t
-H5D__virtual_construct(H5F_t UNUSED *f, H5D_t *dset)
+herr_t
+H5D__virtual_init(H5F_t UNUSED *f, hid_t UNUSED dxpl_id, const H5D_t *dset,
+    hid_t dapl_id)
 {
-    size_t              i;
-    herr_t              ret_value = SUCCEED;
+    H5P_genplist_t *dapl;               /* Data access property list object pointer */
+    size_t      i;                      /* Local index variable */
+    herr_t      ret_value = SUCCEED;    /* Return value */
 
-    FUNC_ENTER_STATIC
+    FUNC_ENTER_PACKAGE
 
+    /* Sanity check */
+    HDassert(dset);
     HDassert(dset->shared->layout.storage.u.virt.list || (dset->shared->layout.storage.u.virt.list_nused == 0));
 
     /* Patch the virtual selection dataspaces */
     for(i = 0; i < dset->shared->layout.storage.u.virt.list_nused; i++) {
-        HDassert(dset->shared->layout.storage.u.virt.list[i].virtual_space_status == H5O_VIRTUAL_STATUS_USER);
-        if(H5S_extent_copy(dset->shared->layout.storage.u.virt.list[i].virtual_select, dset->shared->space) < 0)
-            HGOTO_ERROR(H5E_DATASET, H5E_CANTCOPY, FAIL, "can't copy virtual dataspace extent")
-        dset->shared->layout.storage.u.virt.list[i].virtual_space_status = H5O_VIRTUAL_STATUS_CORRECT;
+        if(dset->shared->layout.storage.u.virt.list[i].virtual_space_status != H5O_VIRTUAL_STATUS_CORRECT) {
+            if(H5S_extent_copy(dset->shared->layout.storage.u.virt.list[i].virtual_select, dset->shared->space) < 0)
+                HGOTO_ERROR(H5E_DATASET, H5E_CANTCOPY, FAIL, "can't copy virtual dataspace extent")
+            dset->shared->layout.storage.u.virt.list[i].virtual_space_status = H5O_VIRTUAL_STATUS_CORRECT;
+        } /* end if */
     } /* end for */
 
+    /* Get dataset access property list */
+    if(NULL == (dapl = (H5P_genplist_t *)H5I_object(dapl_id)))
+        HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "can't find object for dapl ID")
+
+    /* Get bounds option */
+    if(H5P_get(dapl, H5D_ACS_VDS_BOUNDS_NAME, &dset->shared->layout.storage.u.virt.bounds) < 0)
+        HGOTO_ERROR(H5E_PLIST, H5E_CANTGET,FAIL, "can't get data cache number of slots")
+
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5D__virtual_construct() */
+} /* end H5D__virtual_init() */
 
 
 /*-------------------------------------------------------------------------
@@ -759,11 +770,7 @@ H5D__virtual_read(H5D_io_info_t *io_info, const H5D_type_info_t *type_info,
     HDassert(file_space);
 
     storage = &io_info->dset->shared->layout.storage.u.virt;
-
-    /* Update VDS extent due to unlimited selections */
-    /* Don't call if there is no unlimited selection? VDSINC */
-    if(H5D__virtual_set_extent_unlim(io_info->dset, io_info->dxpl_id) < 0)
-        HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to update virtual dataset extent")
+    HDassert((storage->bounds == H5D_VDS_MAX) || (storage->bounds == H5D_VDS_MIN));
 
     /* Iterate over mappings */
     for(i = 0; i < storage->list_nused; i++) {
@@ -871,11 +878,7 @@ H5D__virtual_write(H5D_io_info_t *io_info, const H5D_type_info_t *type_info,
     HDassert(file_space);
 
     storage = &io_info->dset->shared->layout.storage.u.virt;
-
-    /* Update VDS extent due to unlimited selections */
-    /* Don't call if there is no unlimited selection? VDSINC */
-    if(H5D__virtual_set_extent_unlim(io_info->dset, io_info->dxpl_id) < 0)
-        HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to update virtual dataset extent")
+    HDassert((storage->bounds == H5D_VDS_MAX) || (storage->bounds == H5D_VDS_MIN));
 
     /* Iterate over mappings */
     for(i = 0; i < storage->list_nused; i++) {
diff --git a/src/H5Olayout.c b/src/H5Olayout.c
index cf5b3d2..9f1afb3 100644
--- a/src/H5Olayout.c
+++ b/src/H5Olayout.c
@@ -251,7 +251,7 @@ H5O_layout_decode(H5F_t *f, hid_t dxpl_id, H5O_t UNUSED *open_oh,
                 mesg->storage.u.virt.list_nused = 0;
                 mesg->storage.u.virt.list = NULL;
                 mesg->storage.u.virt.list_nalloc = 0;
-                mesg->storage.u.virt.set_extent_max = TRUE;
+                mesg->storage.u.virt.bounds = H5D_VDS_ERROR;
 
                 /* Decode heap block if it exists */
                 if(mesg->storage.u.virt.serial_list_hobjid.addr != HADDR_UNDEF) {
diff --git a/src/H5Oprivate.h b/src/H5Oprivate.h
index 0211093..fcb0649 100644
--- a/src/H5Oprivate.h
+++ b/src/H5Oprivate.h
@@ -450,7 +450,7 @@ typedef struct H5O_storage_virtual_t {
     /* Not stored */
     size_t      list_nalloc;            /* Number of slots allocated          */
     hsize_t     min_dims[H5S_MAX_RANK]; /* Minimum extent of VDS (maximum of all non-unlimited selection bounds) */
-    hbool_t     set_extent_max;         /* Whether we set the extent by the maximum (TRUE) or minimum (FALSE) of unlimited selections */
+    H5D_vds_bounds_t bounds;         /* Whether we set the extent by the maximum (TRUE) or minimum (FALSE) of unlimited selections */
 } H5O_storage_virtual_t;
 
 typedef struct H5O_storage_t {
diff --git a/src/H5Pdapl.c b/src/H5Pdapl.c
index 93d16bb..fbd83a6 100644
--- a/src/H5Pdapl.c
+++ b/src/H5Pdapl.c
@@ -61,6 +61,11 @@
 #define H5D_ACS_PREEMPT_READ_CHUNKS_DEF         H5D_CHUNK_CACHE_W0_DEFAULT
 #define H5D_ACS_PREEMPT_READ_CHUNKS_ENC         H5P__encode_double
 #define H5D_ACS_PREEMPT_READ_CHUNKS_DEC         H5P__decode_double
+/* Definitions for VDS bounds option */
+#define H5D_ACS_VDS_BOUNDS_SIZE                 sizeof(H5D_vds_bounds_t)
+#define H5D_ACS_VDS_BOUNDS_DEF                  H5D_VDS_MAX
+#define H5D_ACS_VDS_BOUNDS_ENC                  H5P__dacc_vds_bounds_enc
+#define H5D_ACS_VDS_BOUNDS_DEC                  H5P__dacc_vds_bounds_dec
 
 /******************/
 /* Local Typedefs */
@@ -79,6 +84,10 @@
 /* Property class callbacks */
 static herr_t H5P__dacc_reg_prop(H5P_genclass_t *pclass);
 
+/* Property list callbacks */
+static herr_t H5P__dacc_vds_bounds_enc(const void *value, void **pp, size_t *size);
+static herr_t H5P__dacc_vds_bounds_dec(const void **pp, void *value);
+
 
 /*********************/
 /* Package Variables */
@@ -133,6 +142,7 @@ H5P__dacc_reg_prop(H5P_genclass_t *pclass)
     size_t rdcc_nslots = H5D_ACS_DATA_CACHE_NUM_SLOTS_DEF;      /* Default raw data chunk cache # of slots */
     size_t rdcc_nbytes = H5D_ACS_DATA_CACHE_BYTE_SIZE_DEF;      /* Default raw data chunk cache # of bytes */
     double rdcc_w0 = H5D_ACS_PREEMPT_READ_CHUNKS_DEF;           /* Default raw data chunk cache dirty ratio */
+    H5D_vds_bounds_t bounds_option = H5D_ACS_VDS_BOUNDS_DEF;    /* Default VDS bounds option */
     herr_t ret_value = SUCCEED;         /* Return value */
 
     FUNC_ENTER_STATIC
@@ -152,6 +162,12 @@ H5P__dacc_reg_prop(H5P_genclass_t *pclass)
              NULL, NULL, NULL, H5D_ACS_PREEMPT_READ_CHUNKS_ENC, H5D_ACS_PREEMPT_READ_CHUNKS_DEC, NULL, NULL, NULL, NULL) < 0)
          HGOTO_ERROR(H5E_PLIST, H5E_CANTINSERT, FAIL, "can't insert property into class")
 
+    /* Register the VDS bounds option */
+    if(H5P_register_real(pclass, H5D_ACS_VDS_BOUNDS_NAME, H5D_ACS_VDS_BOUNDS_SIZE, &bounds_option,
+            NULL, NULL, NULL, H5D_ACS_VDS_BOUNDS_ENC, H5D_ACS_VDS_BOUNDS_DEC,
+            NULL, NULL, NULL, NULL) < 0)
+        HGOTO_ERROR(H5E_PLIST, H5E_CANTINSERT, FAIL, "can't insert property into class")
+
 done:
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5P__dacc_reg_prop() */
@@ -282,5 +298,147 @@ H5Pget_chunk_cache(hid_t dapl_id, size_t *rdcc_nslots, size_t *rdcc_nbytes, doub
 
 done:
     FUNC_LEAVE_API(ret_value)
-}
+} /* end H5Pget_chunk_cache() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5Pset_virtual_dataspace_bounds
+ *
+ * Purpose:     VDSINC
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  Neil Fortner
+ *              May 4, 2015
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5Pset_virtual_dataspace_bounds(hid_t plist_id, H5D_vds_bounds_t bounds_option)
+{
+    H5P_genplist_t *plist;      /* Property list pointer */
+    herr_t ret_value = SUCCEED; /* return value */
+
+    FUNC_ENTER_API(FAIL)
+
+    /* Check argument */
+    if((bounds_option != H5D_VDS_MAX) && (bounds_option != H5D_VDS_MIN))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "not a valid bounds option")
+
+    /* Get the plist structure */
+    if(NULL == (plist = H5P_object_verify(plist_id, H5P_DATASET_ACCESS)))
+        HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "can't find object for ID")
+
+    /* Update property list */
+    if(H5P_set(plist, H5D_ACS_VDS_BOUNDS_NAME, &bounds_option) < 0)
+        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "unable to set value")
+
+done:
+    FUNC_LEAVE_API(ret_value)
+} /* end H5Pset_virtual_dataspace_bounds() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5Pget_virtual_dataspace_bounds
+ *
+ * Purpose:     VDSINC
+ *
+ * Return:      Success:        H5D_VDS_MAX or H5D_VDS_MIN
+ *              Failure:        H5D_VDS_ERROR
+ *
+ * Programmer:  Neil Fortner
+ *              May 4, 2015
+ *
+ *-------------------------------------------------------------------------
+ */
+H5D_vds_bounds_t
+H5Pget_virtual_dataspace_bounds(hid_t plist_id)
+{
+    H5P_genplist_t *plist;      /* Property list pointer */
+    H5D_vds_bounds_t ret_value;   /* Return value */
+
+    FUNC_ENTER_API(H5D_VDS_ERROR)
+
+    /* Get the plist structure */
+    if(NULL == (plist = H5P_object_verify(plist_id, H5P_DATASET_ACCESS)))
+        HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, H5D_VDS_ERROR, "can't find object for ID")
+
+    /* Get value from property list */
+    if(H5P_get(plist, H5D_ACS_VDS_BOUNDS_NAME, &ret_value) < 0)
+        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, H5D_VDS_ERROR, "unable to set value")
+
+done:
+    FUNC_LEAVE_API(ret_value)
+} /* end H5Pget_virtual_dataspace_bounds() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5P__dacc_vds_bounds_enc
+ *
+ * Purpose:     Callback routine which is called whenever the vds bounds
+ *              property in the dataset access property list is encoded.
+ *
+ * Return:      Success:        Non-negative
+ *              Failure:        Negative
+ *
+ * Programmer:  Neil Fortner
+ *              Tuesday, May 5, 2015
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5P__dacc_vds_bounds_enc(const void *value, void **_pp, size_t *size)
+{
+    const H5D_vds_bounds_t *bounds = (const H5D_vds_bounds_t *)value; /* Create local alias for values */
+    uint8_t **pp = (uint8_t **)_pp;
+
+    FUNC_ENTER_STATIC_NOERR
+
+    /* Sanity check */
+    HDassert(bounds);
+    HDassert(size);
+
+    if(NULL != *pp)
+        /* Encode EDC property */
+        *(*pp)++ = (uint8_t)*bounds;
+
+    /* Size of EDC property */
+    (*size)++;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5P__dacc_vds_bounds_enc() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5P__dacc_vds_bounds_dec
+ *
+ * Purpose:     Callback routine which is called whenever the vds bounds
+ *              property in the dataset access property list is encoded.
+ *
+ * Return:      Success:        Non-negative
+ *              Failure:        Negative
+ *
+ * Programmer:  Neil Fortner
+ *              Tuesday, May 5, 2015
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5P__dacc_vds_bounds_dec(const void **_pp, void *_value)
+{
+    H5D_vds_bounds_t *bounds = (H5D_vds_bounds_t *)_value;         /* EDC property */
+    const uint8_t **pp = (const uint8_t **)_pp;
+
+    FUNC_ENTER_STATIC_NOERR
+
+    /* Sanity checks */
+    HDassert(pp);
+    HDassert(*pp);
+    HDassert(bounds);
+
+    /* Decode EDC property */
+    *bounds = (H5D_vds_bounds_t)*(*pp)++;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5P__dacc_vds_bounds_dec() */
 
diff --git a/src/H5Ppublic.h b/src/H5Ppublic.h
index c1c6f17..7932716 100644
--- a/src/H5Ppublic.h
+++ b/src/H5Ppublic.h
@@ -393,6 +393,9 @@ H5_DLL herr_t H5Pget_chunk_cache(hid_t dapl_id,
        size_t *rdcc_nslots/*out*/,
        size_t *rdcc_nbytes/*out*/,
        double *rdcc_w0/*out*/);
+H5_DLL herr_t H5Pset_virtual_dataspace_bounds(hid_t plist_id,
+       H5D_vds_bounds_t bounds_option);
+H5_DLL H5D_vds_bounds_t H5Pget_virtual_dataspace_bounds(hid_t plist_id);
 
 /* Dataset xfer property list (DXPL) routines */
 H5_DLL herr_t H5Pset_data_transform(hid_t plist_id, const char* expression);
diff --git a/src/H5Shyper.c b/src/H5Shyper.c
index 9b854c0..5667cbd 100644
--- a/src/H5Shyper.c
+++ b/src/H5Shyper.c
@@ -1673,20 +1673,9 @@ H5S_hyper_copy (H5S_t *dst, const H5S_t *src, hbool_t share_selection)
             dst->select.sel_info.hslab->span_lst = H5S_hyper_copy_span(src->select.sel_info.hslab->span_lst);
     } /* end if */
 
-    /* If there is an unlimited dimension, we must update the selection if the
-     * extent changed */
-    if(dst_hslab->unlim_dim >= 0) {
-        htri_t extent_equal;
-
-        /* Check if the extent changed */
-        if((extent_equal = H5S_extent_equal(src, dst)) < 0)
-            HGOTO_ERROR(H5E_DATASPACE, H5E_CANTCOMPARE, FAIL, "dataspace comparison failed")
-
-        if(!extent_equal)
-            /* Update selection due to changed extent */
-            if(H5S_hyper_clip_to_extent(dst) < 0)
-                HGOTO_ERROR(H5E_DATASPACE, H5E_CANTSET, FAIL, "can't update hyperslab")
-    } /* end if */
+    /* If there is an unlimited dimension, we must update the selection */
+    if(H5S_hyper_clip_to_extent(dst) < 0)
+        HGOTO_ERROR(H5E_DATASPACE, H5E_CANTSET, FAIL, "can't update hyperslab")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
@@ -9843,14 +9832,12 @@ H5S_hyper_get_clip_extent(const H5S_t *clip_space, const H5S_t *match_space,
                     + ((count - (hsize_t)1)
                     * clip_hslab->opt_unlim_diminfo[clip_hslab->unlim_dim].stride)
                     + clip_hslab->opt_unlim_diminfo[clip_hslab->unlim_dim].block;
-            if(clip_size_incl_trail) {
-                HDassert(0 && "Checking code coverage..."); //VDSINC
+            if(clip_size_incl_trail)
                 /* Include gap after last block */
                 *clip_size_incl_trail =
                         clip_hslab->opt_unlim_diminfo[clip_hslab->unlim_dim].start
                         + (count
                         * clip_hslab->opt_unlim_diminfo[clip_hslab->unlim_dim].stride);
-            } //VDSINC
         } /* end else */
     } /* end else */