[svn-r24734] - Add iteration feature at the server with a callback on every object under the starting location.

- Implement view creation for element region on all dataset under a group.
- Add the creation propertly list to the token buffer since they are used now in the FF plugin.

4 files changed, 433 insertions, 23 deletions

diff --git a/src/H5VLiod.c b/src/H5VLiod.c
index 1dbd8d0..bd5be88 100644
--- a/src/H5VLiod.c
+++ b/src/H5VLiod.c
@@ -21,6 +21,8 @@
  *              by the function shipper.
  */
 
+#define H5P_PACKAGE		/*suppress error about including H5Ppkg	  */
+
 /* Interface initialization */
 #define H5_INTERFACE_INIT_FUNC	H5VL_iod_init_interface
 
@@ -31,6 +33,7 @@
 #include "H5Iprivate.h"		/* IDs			  		*/
 #include "H5MMprivate.h"	/* Memory management			*/
 #include "H5Pprivate.h"		/* Property lists			*/
+#include "H5Ppkg.h"		/* Property lists			*/
 #include "H5Sprivate.h"		/* Dataspaces		  		*/
 #include "H5VLprivate.h"	/* VOL plugins				*/
 #include "H5VLiod.h"            /* Iod VOL plugin			*/
@@ -6097,7 +6100,18 @@ H5VL_iod_obj_open_token(const void *token, H5TR_t *tr, H5I_type_t *opened_type,
         dset->remote_dset.attrkv_id = attrkv_id;
 
         dset->dapl_id = H5Pcopy(H5P_DATASET_ACCESS_DEFAULT);
-        dset->remote_dset.dcpl_id = H5Pcopy(H5P_DATASET_CREATE_DEFAULT);
+
+        /* decode creation property list */
+        {
+            size_t plist_size;
+
+            HDmemcpy(&plist_size, buf_ptr, sizeof(size_t));
+            buf_ptr += sizeof(size_t);
+            /* Create plist by decoding buffer */
+            if((dset->remote_dset.dcpl_id = H5P__decode((const void *)buf_ptr)) < 0)
+                HGOTO_ERROR(H5E_PLIST, H5E_CANTDECODE, NULL, "can't decode object");
+            buf_ptr += plist_size;
+        }
 
         /* decode dtype */
         {
@@ -6166,7 +6180,18 @@ H5VL_iod_obj_open_token(const void *token, H5TR_t *tr, H5I_type_t *opened_type,
         dtype->remote_dtype.attrkv_id = attrkv_id;
 
         dtype->tapl_id = H5Pcopy(H5P_DATATYPE_ACCESS_DEFAULT);
-        dtype->remote_dtype.tcpl_id = H5Pcopy(H5P_DATATYPE_CREATE_DEFAULT);
+
+        /* decode creation property list */
+        {
+            size_t plist_size;
+
+            HDmemcpy(&plist_size, buf_ptr, sizeof(size_t));
+            buf_ptr += sizeof(size_t);
+            /* Create plist by decoding buffer */
+            if((dtype->remote_dtype.tcpl_id = H5P__decode((const void *)buf_ptr)) < 0)
+                HGOTO_ERROR(H5E_PLIST, H5E_CANTDECODE, NULL, "can't decode object");
+            buf_ptr += plist_size;
+        }
 
         /* decode dtype */
         {
@@ -6220,9 +6245,20 @@ H5VL_iod_obj_open_token(const void *token, H5TR_t *tr, H5I_type_t *opened_type,
         grp->remote_group.mdkv_id = mdkv_id;
         grp->remote_group.attrkv_id = attrkv_id;
 
-        grp->remote_group.gcpl_id = H5Pcopy(H5P_GROUP_CREATE_DEFAULT);
         grp->gapl_id = H5Pcopy(H5P_GROUP_ACCESS_DEFAULT);
 
+        /* decode creation property list */
+        {
+            size_t plist_size;
+
+            HDmemcpy(&plist_size, buf_ptr, sizeof(size_t));
+            buf_ptr += sizeof(size_t);
+            /* Create plist by decoding buffer */
+            if((grp->remote_group.gcpl_id = H5P__decode((const void *)buf_ptr)) < 0)
+                HGOTO_ERROR(H5E_PLIST, H5E_CANTDECODE, NULL, "can't decode object");
+            buf_ptr += plist_size;
+        }
+
         /* set the input structure for the HG encode routine */
         input.coh = tr->file->remote_file.coh;
         input.iod_id = iod_id;
@@ -6259,9 +6295,20 @@ H5VL_iod_obj_open_token(const void *token, H5TR_t *tr, H5I_type_t *opened_type,
         map->remote_map.mdkv_id = mdkv_id;
         map->remote_map.attrkv_id = attrkv_id;
 
-        map->remote_map.mcpl_id = H5Pcopy(H5P_MAP_CREATE_DEFAULT);
         map->mapl_id = H5Pcopy(H5P_MAP_ACCESS_DEFAULT);
 
+        /* decode creation property list */
+        {
+            size_t plist_size;
+
+            HDmemcpy(&plist_size, buf_ptr, sizeof(size_t));
+            buf_ptr += sizeof(size_t);
+            /* Create plist by decoding buffer */
+            if((map->remote_map.mcpl_id = H5P__decode((const void *)buf_ptr)) < 0)
+                HGOTO_ERROR(H5E_PLIST, H5E_CANTDECODE, NULL, "can't decode object");
+            buf_ptr += plist_size;
+        }
+
         /* decode key_type */
         {
             H5T_t *dt = NULL;
@@ -6430,9 +6477,11 @@ H5VL_iod_get_token(void *_obj, void *token, size_t *token_size)
     iod_obj_id_t iod_id, mdkv_id, attrkv_id;
     H5O_type_t type;
     uint8_t *buf_ptr = (uint8_t *)token;
-    size_t dt_size = 0, space_size = 0;
+    size_t dt_size = 0, space_size = 0, plist_size = 0;
     H5T_t *dt = NULL;
     H5S_t *space = NULL;
+    H5P_genplist_t *plist = NULL;
+    hid_t cpl_id;
     size_t keytype_size = 0, valtype_size;
     H5T_t *kt = NULL, *vt = NULL;
     herr_t ret_value = SUCCEED;              /* Return value */
@@ -6443,11 +6492,23 @@ H5VL_iod_get_token(void *_obj, void *token, size_t *token_size)
 
     switch(obj->obj_type) {
         case H5I_GROUP:
-            iod_id = ((const H5VL_iod_group_t *)obj)->remote_group.iod_id;
-            mdkv_id = ((const H5VL_iod_group_t *)obj)->remote_group.mdkv_id;
-            attrkv_id = ((const H5VL_iod_group_t *)obj)->remote_group.attrkv_id;
-            type = H5O_TYPE_GROUP;
-            break;
+            {
+                H5VL_iod_group_t *grp = (H5VL_iod_group_t *)obj;
+
+                iod_id = grp->remote_group.iod_id;
+                mdkv_id = grp->remote_group.mdkv_id;
+                attrkv_id = grp->remote_group.attrkv_id;
+                type = H5O_TYPE_GROUP;
+
+                cpl_id = grp->remote_group.gcpl_id;
+                if(NULL == (plist = (H5P_genplist_t *)H5I_object_verify(cpl_id, H5I_GENPROP_LST)))
+                    HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list")
+                if(H5P__encode(plist, TRUE, NULL, &plist_size) < 0)
+                    HGOTO_ERROR(H5E_DATATYPE, H5E_CANTENCODE, FAIL, "can't encode plist")
+
+                *token_size += plist_size + sizeof(size_t);
+                break;
+            }
         case H5I_DATASET:
             {
                 H5VL_iod_dset_t *dset = (H5VL_iod_dset_t *)obj;
@@ -6470,7 +6531,13 @@ H5VL_iod_get_token(void *_obj, void *token, size_t *token_size)
                 if(H5S_encode(space, NULL, &space_size) < 0)
                     HGOTO_ERROR(H5E_DATASPACE, H5E_CANTENCODE, FAIL, "can't encode dataspace")
 
-                *token_size += dt_size + space_size + sizeof(size_t)*2;
+                cpl_id = dset->remote_dset.dcpl_id;
+                if(NULL == (plist = (H5P_genplist_t *)H5I_object_verify(cpl_id, H5I_GENPROP_LST)))
+                    HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list");
+                if(H5P__encode(plist, TRUE, NULL, &plist_size) < 0)
+                    HGOTO_ERROR(H5E_DATATYPE, H5E_CANTENCODE, FAIL, "can't encode plist")
+
+                *token_size += plist_size + dt_size + space_size + sizeof(size_t)*3;
 
                 break;
             }
@@ -6490,7 +6557,13 @@ H5VL_iod_get_token(void *_obj, void *token, size_t *token_size)
                 if(H5T_encode(dt, NULL, &dt_size) < 0)
                     HGOTO_ERROR(H5E_DATATYPE, H5E_CANTENCODE, FAIL, "can't encode datatype")
 
-                *token_size += dt_size + sizeof(size_t);
+                cpl_id = dtype->remote_dtype.tcpl_id;
+                if(NULL == (plist = (H5P_genplist_t *)H5I_object_verify(cpl_id, H5I_GENPROP_LST)))
+                    HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list");
+                if(H5P__encode(plist, TRUE, NULL, &plist_size) < 0)
+                    HGOTO_ERROR(H5E_DATATYPE, H5E_CANTENCODE, FAIL, "can't encode plist")
+
+                *token_size += dt_size + plist_size + sizeof(size_t)*2;
 
                 break;
             }
@@ -6517,7 +6590,13 @@ H5VL_iod_get_token(void *_obj, void *token, size_t *token_size)
                 if(H5T_encode(vt, NULL, &valtype_size) < 0)
                     HGOTO_ERROR(H5E_DATATYPE, H5E_CANTENCODE, FAIL, "can't encode datatype")
 
-                *token_size += keytype_size + valtype_size + sizeof(size_t)*2;
+                cpl_id = map->remote_map.mcpl_id;
+                if(NULL == (plist = (H5P_genplist_t *)H5I_object_verify(cpl_id, H5I_GENPROP_LST)))
+                    HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list");
+                if(H5P__encode(plist, TRUE, NULL, &plist_size) < 0)
+                    HGOTO_ERROR(H5E_DATATYPE, H5E_CANTENCODE, FAIL, "can't encode plist")
+
+                *token_size += keytype_size + valtype_size + plist_size + sizeof(size_t)*3;
 
                 break;
             }
@@ -6556,8 +6635,19 @@ H5VL_iod_get_token(void *_obj, void *token, size_t *token_size)
 
         switch(obj->obj_type) {
         case H5I_GROUP:
+            HDmemcpy(buf_ptr, &plist_size, sizeof(size_t));
+            buf_ptr += sizeof(size_t);
+            if(H5P__encode(plist, TRUE, buf_ptr, &plist_size) < 0)
+                HGOTO_ERROR(H5E_DATASPACE, H5E_CANTENCODE, FAIL, "can't encode dataspace")
+            buf_ptr += plist_size;
             break;
         case H5I_DATASET:
+            HDmemcpy(buf_ptr, &plist_size, sizeof(size_t));
+            buf_ptr += sizeof(size_t);
+            if(H5P__encode(plist, TRUE, buf_ptr, &plist_size) < 0)
+                HGOTO_ERROR(H5E_DATASPACE, H5E_CANTENCODE, FAIL, "can't encode dataspace")
+            buf_ptr += plist_size;
+
             HDmemcpy(buf_ptr, &dt_size, sizeof(size_t));
             buf_ptr += sizeof(size_t);
             if(H5T_encode(dt, buf_ptr, &dt_size) < 0)
@@ -6571,6 +6661,12 @@ H5VL_iod_get_token(void *_obj, void *token, size_t *token_size)
             buf_ptr += space_size;
             break;
         case H5I_DATATYPE:
+            HDmemcpy(buf_ptr, &plist_size, sizeof(size_t));
+            buf_ptr += sizeof(size_t);
+            if(H5P__encode(plist, TRUE, buf_ptr, &plist_size) < 0)
+                HGOTO_ERROR(H5E_DATASPACE, H5E_CANTENCODE, FAIL, "can't encode dataspace")
+            buf_ptr += plist_size;
+
             HDmemcpy(buf_ptr, &dt_size, sizeof(size_t));
             buf_ptr += sizeof(size_t);
             if(H5T_encode(dt, buf_ptr, &dt_size) < 0)
@@ -6578,6 +6674,12 @@ H5VL_iod_get_token(void *_obj, void *token, size_t *token_size)
             buf_ptr += dt_size;
             break;
         case H5I_MAP:
+            HDmemcpy(buf_ptr, &plist_size, sizeof(size_t));
+            buf_ptr += sizeof(size_t);
+            if(H5P__encode(plist, TRUE, buf_ptr, &plist_size) < 0)
+                HGOTO_ERROR(H5E_DATASPACE, H5E_CANTENCODE, FAIL, "can't encode dataspace")
+            buf_ptr += plist_size;
+
             HDmemcpy(buf_ptr, &keytype_size, sizeof(size_t));
             buf_ptr += sizeof(size_t);
             if(H5T_encode(kt, buf_ptr, &keytype_size) < 0)
@@ -9907,7 +10009,7 @@ H5VL_iod_view_create(void *_obj, hid_t query_id, hid_t vcpl_id, hid_t rcxt_id, v
 
     /* store the query ID */
     view->query_id = query_id;
-    if(H5I_inc_ref(query_id, FALSE) < 0)
+    if(H5I_inc_ref(query_id, TRUE) < 0)
         HGOTO_ERROR(H5E_ATOM, H5E_CANTINC, NULL, "can't increment ID ref count");
 
     /* copy property list */
diff --git a/src/H5VLiod_server.h b/src/H5VLiod_server.h
index d49e323..7ebb609 100644
--- a/src/H5VLiod_server.h
+++ b/src/H5VLiod_server.h
@@ -90,6 +90,10 @@ extern hg_id_t H5VL_EFF_CLOSE_CONTAINER;
 extern hg_id_t H5VL_EFF_ANALYSIS_FARM;
 extern hg_id_t H5VL_EFF_ANALYSIS_FARM_TRANSFER;
 
+/* Define the operator function pointer for H5Diterate() */
+typedef herr_t (*H5VL_operator_t)(iod_handle_t coh, iod_obj_id_t obj_id, iod_trans_id_t rtid,
+                                  H5I_type_t obj_type, uint32_t cs_scope, void *operator_data);
+
 H5_DLL void EFF__mercury_register_callbacks(void);
 
 H5_DLL int H5VL_iod_server_analysis_execute(hg_handle_t handle);
@@ -444,6 +448,10 @@ H5_DLL herr_t H5VL__iod_server_final_io(iod_handle_t iod_oh, hid_t space_id, siz
                                         hbool_t write_op, void *buf, size_t buf_size, 
                                         iod_checksum_t cs, uint32_t cs_scope, iod_trans_id_t tid);
 
+H5_DLL herr_t H5VL_iod_server_iterate(iod_handle_t coh, iod_obj_id_t obj_id, iod_trans_id_t rtid,
+                                      H5I_type_t obj_type, uint32_t cs_scope, 
+                                      H5VL_operator_t op, void *op_data);
+
 H5_DLL herr_t H5VL__iod_get_query_data_cb(void *elem, hid_t type_id, unsigned ndim, 
                                           const hsize_t *point, void *_udata);
 #endif /* H5_HAVE_EFF */
diff --git a/src/H5VLiod_util.c b/src/H5VLiod_util.c
index c577ecb..a67d7b8 100644
--- a/src/H5VLiod_util.c
+++ b/src/H5VLiod_util.c
@@ -22,6 +22,9 @@
 
 #ifdef H5_HAVE_EFF
 
+static H5I_type_t H5VL__iod_get_h5_obj_type(iod_obj_id_t oid, iod_handle_t coh, 
+                                            iod_trans_id_t rtid, uint32_t cs_scope);
+
 /*
  * Programmer:  Mohamad Chaarawi <chaarawi@hdfgroup.gov>
  *              February, 2013
@@ -1243,6 +1246,183 @@ done:
     FUNC_LEAVE_NOAPI(ret_value)
 } /* H5VL_iod_verify_kv_pair */
 
+
+/*-------------------------------------------------------------------------
+ * Function:	H5VL__iod_get_h5_obj_type
+ *
+ * Purpose:     Function to retrieve the HDF5 object type of an IOD object.
+ *
+ * Return:	Success:	SUCCEED 
+ *		Failure:	Negative
+ *
+ *-------------------------------------------------------------------------
+ */
+static H5I_type_t 
+H5VL__iod_get_h5_obj_type(iod_obj_id_t oid, iod_handle_t coh, iod_trans_id_t rtid, uint32_t cs_scope)
+{
+    iod_handle_t mdkv_oh, oh;
+    H5I_type_t obj_type;
+    iod_obj_type_t iod_type;
+    herr_t ret_value = -1;
+
+    FUNC_ENTER_NOAPI_NOINIT
+
+    iod_type = IOD_OBJID_GETTYPE(oid);
+
+    if(IOD_OBJ_ARRAY == iod_type)
+        obj_type = H5I_DATASET;
+    else if(IOD_OBJ_BLOB == iod_type)
+        obj_type = H5I_DATATYPE;
+    else {
+        scratch_pad sp;
+        iod_checksum_t sp_cs = 0;
+
+        if (iod_obj_open_read(coh, oid, rtid, NULL /*hints*/, &oh, NULL) < 0)
+            HGOTO_ERROR2(H5E_FILE, H5E_CANTINIT, FAIL, "can't open object");
+
+        /* get scratch pad of the object */
+        if(iod_obj_get_scratch(oh, rtid, &sp, &sp_cs, NULL) < 0)
+            HGOTO_ERROR2(H5E_FILE, H5E_CANTINIT, FAIL, "can't get scratch pad for object");
+        if(sp_cs && (cs_scope & H5_CHECKSUM_IOD)) {
+            /* verify scratch pad integrity */
+            if(H5VL_iod_verify_scratch_pad(&sp, sp_cs) < 0)
+                HGOTO_ERROR2(H5E_SYM, H5E_CANTINIT, FAIL, "Scratch Pad failed integrity check");
+        }
+
+        /* open the metadata KV */
+        if (iod_obj_open_read(coh, sp[0], rtid, NULL /*hints*/, &mdkv_oh, NULL) < 0)
+            HGOTO_ERROR2(H5E_FILE, H5E_CANTINIT, FAIL, "can't open MDKV");
+
+        if(H5VL_iod_get_metadata(mdkv_oh, rtid, H5VL_IOD_OBJECT_TYPE, H5VL_IOD_KEY_OBJ_TYPE,
+                                 cs_scope, NULL, &obj_type) < 0)
+            HGOTO_ERROR2(H5E_SYM, H5E_CANTGET, FAIL, "failed to retrieve link count");
+
+        if(iod_obj_close(mdkv_oh, NULL, NULL) < 0)
+            HGOTO_ERROR2(H5E_SYM, H5E_CANTINIT, FAIL, "can't close current object handle");
+        if(iod_obj_close(oh, NULL, NULL) < 0)
+            HGOTO_ERROR2(H5E_SYM, H5E_CANTINIT, FAIL, "can't close current object handle");
+    }
+
+    ret_value = obj_type;
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5VL__iod_get_h5_obj_type() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5VL_iod_server_iterate
+ *
+ * Purpose: 
+ *
+ * Return:	Success:	SUCCEED 
+ *		Failure:	Negative
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t 
+H5VL_iod_server_iterate(iod_handle_t coh, iod_obj_id_t obj_id, iod_trans_id_t rtid,
+                        H5I_type_t obj_type, uint32_t cs_scope, 
+                        H5VL_operator_t op, void *op_data)
+{
+    iod_handle_t obj_oh;
+    herr_t ret;
+    herr_t ret_value = SUCCEED;
+
+    FUNC_ENTER_NOAPI_NOINIT
+
+    ret = (*op)(coh, obj_id, rtid, obj_type, cs_scope, op_data);
+
+    /* Get the object type, if it is not a group do not check for links */
+    if(H5I_GROUP == obj_type) {
+        int num_entries;
+
+        /* Get the object ID and iterate into every member in the group */
+        if (iod_obj_open_read(coh, obj_id, rtid, NULL, &obj_oh, NULL) < 0)
+            HGOTO_ERROR2(H5E_SYM, H5E_CANTINIT, FAIL, "can't open current group");
+
+        ret = iod_kv_get_num(obj_oh, rtid, &num_entries, NULL);
+        if(ret != 0)
+            HGOTO_ERROR_IOD(ret, FAIL, "can't get number of KV entries");
+
+        if(0 != num_entries) {
+            iod_kv_params_t *kvs = NULL;
+            iod_kv_t *kv = NULL;
+            iod_checksum_t *oid_cs = NULL;
+            iod_ret_t *oid_ret = NULL;
+            int i;
+
+            kvs = (iod_kv_params_t *)malloc(sizeof(iod_kv_params_t) * (size_t)num_entries);
+            kv = (iod_kv_t *)malloc(sizeof(iod_kv_t) * (size_t)num_entries);
+            oid_cs = (iod_checksum_t *)malloc(sizeof(iod_checksum_t) * (size_t)num_entries);
+            oid_ret = (iod_ret_t *)malloc(sizeof(iod_ret_t) * (size_t)num_entries);
+
+            for(i=0 ; i<num_entries ; i++) {
+                kv[i].key = malloc(IOD_KV_KEY_MAXLEN);
+                kv[i].key_len = IOD_KV_KEY_MAXLEN;
+                //kv[i].value = malloc(sizeof(iod_obj_id_t));
+                //kv[i].value_len = sizeof(iod_obj_id_t);
+                kvs[i].kv = &kv[i];
+                kvs[i].cs = &oid_cs[i];
+                kvs[i].ret = &oid_ret[i];
+            }
+
+            ret = iod_kv_list_key(obj_oh, rtid, NULL, 0, &num_entries, kvs, NULL);
+            if(ret != 0)
+                HGOTO_ERROR_IOD(ret, FAIL, "can't get list of keys");
+            //ret = iod_kv_get_list(obj_oh, rtid, NULL, 0, &num_entries, kvs, NULL);
+            //if(ret != 0)
+            //HGOTO_ERROR_IOD(ret, FAIL, "can't get KV list from group KV");
+
+            for(i=0 ; i<num_entries ; i++) {
+
+                H5I_type_t otype;
+                iod_obj_id_t oid;// = *((iod_obj_id_t *)kv[i].value);
+                H5VL_iod_link_t value;
+
+                /* lookup object in the current group */
+                if(H5VL_iod_get_metadata(obj_oh, rtid, H5VL_IOD_LINK, 
+                                         (char *)(kv[i].key), cs_scope, NULL, &value) < 0)
+                    HGOTO_ERROR2(H5E_SYM, H5E_CANTGET, FAIL, "failed to retrieve link value");
+
+                if(H5L_TYPE_SOFT == value.link_type) {
+                    continue;
+                }
+                else
+                    oid = value.u.iod_id;
+
+#if H5VL_IOD_DEBUG
+                fprintf(stderr, "Iterating into %s OID %"PRIx64"\n", ((char *)kv[i].key), oid);
+#endif
+
+                /* Get the object type. */
+                if((otype = H5VL__iod_get_h5_obj_type(oid, coh, rtid, cs_scope)) < 0)
+                    HGOTO_ERROR_IOD(ret, FAIL, "can't get object type");
+
+                if(H5VL_iod_server_iterate(coh, oid, rtid, otype, cs_scope, op, op_data) < 0)
+                    HGOTO_ERROR_IOD(ret, FAIL, "can't iterate");
+            }
+
+            for(i=0 ; i<num_entries ; i++) {
+                free(kv[i].key);
+                //free(kv[i].value);
+            }
+
+            free(kv);
+            free(oid_cs);
+            free(oid_ret);
+            free(kvs);
+        }
+
+        if(iod_obj_close(obj_oh, NULL, NULL) < 0)
+            HGOTO_ERROR2(H5E_SYM, H5E_CANTINIT, FAIL, "can't close current object handle");
+    }
+
+    ret_value = ret;
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+}
+
 #if 0
 herr_t
 H5VL_iod_map_type_convert(hid_t src_id, hid_t dst_id, void *buf, size_t buf_size)
diff --git a/src/H5VLiod_view.c b/src/H5VLiod_view.c
index 62bc9af..4383572 100644
--- a/src/H5VLiod_view.c
+++ b/src/H5VLiod_view.c
@@ -28,6 +28,14 @@
 
 #ifdef H5_HAVE_EFF
 
+typedef struct {
+    hid_t query_id;
+    hid_t vcpl_id;
+    region_info_t region_info;
+    obj_info_t obj_info;
+    attr_info_t attr_info;
+} H5VL_view_op_t;
+
 static hid_t H5VL__iod_get_elmt_region(iod_handle_t coh, iod_obj_id_t dset_id,
                                        iod_trans_id_t rtid, hid_t query_id, 
                                        hid_t vcpl_id, uint32_t cs_scope, binary_buf_t *token);
@@ -37,6 +45,35 @@ H5VL__iod_get_token(H5O_type_t obj_type, iod_obj_id_t iod_id, iod_obj_id_t mdkv_
                     iod_obj_id_t attrkv_id, hid_t cpl_id, hid_t id1, hid_t id2, 
                     binary_buf_t *token);
 
+static herr_t
+H5VL__iod_view_iterate_cb(iod_handle_t coh, iod_obj_id_t obj_id, iod_trans_id_t rtid,
+                       H5I_type_t obj_type, uint32_t cs_scope, void *_op_data)
+{
+    H5VL_view_op_t *op_data = (H5VL_view_op_t *)_op_data;
+    herr_t ret_value = SUCCEED;
+
+    FUNC_ENTER_NOAPI_NOINIT
+
+    if(obj_type == H5I_DATASET) {
+        hsize_t i = op_data->region_info.count;
+
+        op_data->region_info.tokens = (binary_buf_t *)realloc(op_data->region_info.tokens,
+                                                              (i+1) * sizeof(binary_buf_t));
+        op_data->region_info.regions = (hid_t *)realloc(op_data->region_info.regions,
+                                                        (i+1) * sizeof(hid_t));
+
+        if((op_data->region_info.regions[i] = 
+            H5VL__iod_get_elmt_region(coh, obj_id, rtid, op_data->query_id, op_data->vcpl_id,
+                                      cs_scope, &op_data->region_info.tokens[i])) < 0)
+            HGOTO_ERROR2(H5E_FILE, H5E_CANTINIT, FAIL, "can't get region from query");
+
+        op_data->region_info.count ++;
+    }
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+}
+
 /*-------------------------------------------------------------------------
  * Function:	H5VL_iod_server_view_create_cb
  *
@@ -65,10 +102,7 @@ H5VL_iod_server_view_create_cb(AXE_engine_t UNUSED axe_engine,
     hid_t vcpl_id;
     iod_trans_id_t rtid = input->rcxt_num;
     uint32_t cs_scope = input->cs_scope;
-    iod_handle_t mdkv_oh;
-    scratch_pad sp;
-    iod_ret_t ret;
-    hid_t region = FAIL;
+    hsize_t i;
     herr_t ret_value = SUCCEED;
 
     FUNC_ENTER_NOAPI_NOINIT
@@ -96,7 +130,33 @@ H5VL_iod_server_view_create_cb(AXE_engine_t UNUSED axe_engine,
         output.obj_info.tokens = NULL;
         output.attr_info.count = 0;
         output.attr_info.tokens = NULL;
-
+    }
+    else if (H5I_GROUP == obj_type) {
+        H5VL_view_op_t udata;
+
+        udata.query_id = query_id;
+        udata.vcpl_id = vcpl_id;
+
+        udata.region_info.count = 0;
+        udata.region_info.tokens = NULL;
+        udata.region_info.regions = NULL;
+        udata.obj_info.count = 0;
+        udata.obj_info.tokens = NULL;
+        udata.attr_info.count = 0;
+        udata.attr_info.tokens = NULL;
+
+        if(H5VL_iod_server_iterate(coh, loc_id, rtid, obj_type, cs_scope, 
+                                   H5VL__iod_view_iterate_cb, &udata) < 0)
+            HGOTO_ERROR2(H5E_SYM, H5E_CANTINIT, FAIL, "can't iterate to create group");
+
+        output.region_info.count = udata.region_info.count;
+        output.region_info.tokens = udata.region_info.tokens;
+        output.region_info.regions = udata.region_info.regions;
+        output.valid_view = TRUE;
+        output.obj_info.count = 0;
+        output.obj_info.tokens = NULL;
+        output.attr_info.count = 0;
+        output.attr_info.tokens = NULL;
     }
     else {
         /* MSC - for now this is only what is supported */
@@ -117,6 +177,31 @@ done:
 
     HG_Handler_start_output(op_data->hg_handle, &output);
 
+    for(i=0 ; i<output.region_info.count ; i++) {
+        free(output.region_info.tokens[i].buf);
+        H5Sclose(output.region_info.regions[i]);
+    }
+
+    for(i=0 ; i<output.obj_info.count ; i++) {
+        free(output.obj_info.tokens[i].buf);
+    }
+
+    for(i=0 ; i<output.attr_info.count ; i++) {
+        free(output.attr_info.tokens[i].buf);
+    }
+
+    if(output.region_info.tokens)
+        free(output.region_info.tokens);
+
+    if(output.region_info.regions)
+        free(output.region_info.regions);
+
+    if(output.obj_info.tokens)
+        free(output.obj_info.tokens);
+
+    if(output.attr_info.tokens)
+        free(output.attr_info.tokens);
+
     input = (view_create_in_t *)H5MM_xfree(input);
     op_data = (op_data_t *)H5MM_xfree(op_data);
 
@@ -244,7 +329,7 @@ H5VL__iod_get_token(H5O_type_t obj_type, iod_obj_id_t iod_id, iod_obj_id_t mdkv_
                     iod_obj_id_t attrkv_id, hid_t cpl_id, hid_t id1, hid_t id2, 
                     binary_buf_t *token)
 {
-    size_t dt_size = 0, space_size = 0;
+    size_t dt_size = 0, space_size = 0, plist_size = 0;
     size_t keytype_size = 0, valtype_size;
     uint8_t *buf_ptr = NULL;
     size_t token_size = 0;
@@ -256,30 +341,42 @@ H5VL__iod_get_token(H5O_type_t obj_type, iod_obj_id_t iod_id, iod_obj_id_t mdkv_
 
     switch(obj_type) {
     case H5O_TYPE_GROUP:
+        if(H5Pencode(cpl_id, NULL, &plist_size) < 0)
+            HGOTO_ERROR2(H5E_PLIST, H5E_CANTENCODE, FAIL, "can't encode plist");
+        token_size += plist_size + sizeof(size_t);
         break;
     case H5O_TYPE_DATASET:
+        if(H5Pencode(cpl_id, NULL, &plist_size) < 0)
+            HGOTO_ERROR2(H5E_PLIST, H5E_CANTENCODE, FAIL, "can't encode plist");
+
         if(H5Tencode(id1, NULL, &dt_size) < 0)
             HGOTO_ERROR2(H5E_DATATYPE, H5E_CANTENCODE, FAIL, "can't encode datatype");
 
         if(H5Sencode(id2, NULL, &space_size) < 0)
             HGOTO_ERROR2(H5E_DATASPACE, H5E_CANTENCODE, FAIL, "can't encode dataspace");
 
-        token_size += dt_size + space_size + sizeof(size_t)*2;
+        token_size += plist_size + dt_size + space_size + sizeof(size_t)*3;
         break;
     case H5O_TYPE_NAMED_DATATYPE:
+        if(H5Pencode(cpl_id, NULL, &plist_size) < 0)
+            HGOTO_ERROR2(H5E_PLIST, H5E_CANTENCODE, FAIL, "can't encode plist");
+
         if(H5Tencode(id1, NULL, &dt_size) < 0)
             HGOTO_ERROR2(H5E_DATATYPE, H5E_CANTENCODE, FAIL, "can't encode datatype");
 
-        token_size += dt_size + sizeof(size_t);
+        token_size += plist_size + dt_size + sizeof(size_t)*2;
         break;
     case H5O_TYPE_MAP:
+        if(H5Pencode(cpl_id, NULL, &plist_size) < 0)
+            HGOTO_ERROR2(H5E_PLIST, H5E_CANTENCODE, FAIL, "can't encode plist");
+
         if(H5Tencode(id1, NULL, &keytype_size) < 0)
             HGOTO_ERROR2(H5E_DATATYPE, H5E_CANTENCODE, FAIL, "can't encode datatype");
 
         if(H5Tencode(id2, NULL, &valtype_size) < 0)
             HGOTO_ERROR2(H5E_DATATYPE, H5E_CANTENCODE, FAIL, "can't encode datatype");
 
-        token_size += keytype_size + valtype_size + sizeof(size_t)*2;
+        token_size += plist_size + keytype_size + valtype_size + sizeof(size_t)*3;
         break;
     case H5O_TYPE_UNKNOWN:
     case H5O_TYPE_NTYPES:
@@ -302,8 +399,19 @@ H5VL__iod_get_token(H5O_type_t obj_type, iod_obj_id_t iod_id, iod_obj_id_t mdkv_
 
     switch(obj_type) {
     case H5O_TYPE_GROUP:
+        HDmemcpy(buf_ptr, &plist_size, sizeof(size_t));
+        buf_ptr += sizeof(size_t);
+        if(H5Pencode(cpl_id, buf_ptr, &plist_size) < 0)
+            HGOTO_ERROR2(H5E_PLIST, H5E_CANTENCODE, FAIL, "can't encode plist");
+        buf_ptr += plist_size;
         break;
     case H5O_TYPE_DATASET:
+        HDmemcpy(buf_ptr, &plist_size, sizeof(size_t));
+        buf_ptr += sizeof(size_t);
+        if(H5Pencode(cpl_id, buf_ptr, &plist_size) < 0)
+            HGOTO_ERROR2(H5E_PLIST, H5E_CANTENCODE, FAIL, "can't encode plist");
+        buf_ptr += plist_size;
+
         HDmemcpy(buf_ptr, &dt_size, sizeof(size_t));
         buf_ptr += sizeof(size_t);
         if(H5Tencode(id1, buf_ptr, &dt_size) < 0)
@@ -317,6 +425,12 @@ H5VL__iod_get_token(H5O_type_t obj_type, iod_obj_id_t iod_id, iod_obj_id_t mdkv_
         buf_ptr += space_size;
         break;
     case H5O_TYPE_NAMED_DATATYPE:
+        HDmemcpy(buf_ptr, &plist_size, sizeof(size_t));
+        buf_ptr += sizeof(size_t);
+        if(H5Pencode(cpl_id, buf_ptr, &plist_size) < 0)
+            HGOTO_ERROR2(H5E_PLIST, H5E_CANTENCODE, FAIL, "can't encode plist");
+        buf_ptr += plist_size;
+
         HDmemcpy(buf_ptr, &dt_size, sizeof(size_t));
         buf_ptr += sizeof(size_t);
         if(H5Tencode(id1, buf_ptr, &dt_size) < 0)
@@ -324,6 +438,12 @@ H5VL__iod_get_token(H5O_type_t obj_type, iod_obj_id_t iod_id, iod_obj_id_t mdkv_
         buf_ptr += dt_size;
         break;
     case H5O_TYPE_MAP:
+        HDmemcpy(buf_ptr, &plist_size, sizeof(size_t));
+        buf_ptr += sizeof(size_t);
+        if(H5Pencode(cpl_id, buf_ptr, &plist_size) < 0)
+            HGOTO_ERROR2(H5E_PLIST, H5E_CANTENCODE, FAIL, "can't encode plist");
+        buf_ptr += plist_size;
+
         HDmemcpy(buf_ptr, &keytype_size, sizeof(size_t));
         buf_ptr += sizeof(size_t);
         if(H5Tencode(id1, buf_ptr, &keytype_size) < 0)