summaryrefslogtreecommitdiffstats
path: root/src/H5Dcontig.c
blob: 9516d530ed9fd59a07764a3c3556390bc55c459a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * 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 COPYING file, which can be found at the root of the source code       *
 * distribution tree, or in https://support.hdfgroup.org/ftp/HDF5/releases.  *
 * If you do not have access to either file, you may request a copy from     *
 * help@hdfgroup.org.                                                        *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/*
 * Programmer: 	Quincey Koziol <koziol@ncsa.uiuc.edu>
 *	       	Thursday, September 28, 2000
 *
 * Purpose:
 *      Contiguous dataset I/O functions. These routines are similar to
 *      the H5D_chunk_* routines and really only an abstract way of dealing
 *      with the data sieve buffer from H5F_seq_read/write.
 */

/****************/
/* Module Setup */
/****************/

#define H5D_PACKAGE		/*suppress error about including H5Dpkg	  */


/***********/
/* Headers */
/***********/
#include "H5private.h"		/* Generic Functions			*/
#include "H5Dpkg.h"		/* Dataset functions			*/
#include "H5Eprivate.h"		/* Error handling		  	*/
#include "H5Fprivate.h"		/* Files				*/
#include "H5FDprivate.h"	/* File drivers				*/
#include "H5FLprivate.h"	/* Free Lists                           */
#include "H5Iprivate.h"		/* IDs			  		*/
#include "H5MFprivate.h"	/* File memory management		*/
#include "H5Oprivate.h"		/* Object headers		  	*/
#include "H5Pprivate.h"		/* Property lists			*/
#include "H5VMprivate.h"		/* Vector and array functions		*/


/****************/
/* Local Macros */
/****************/


/******************/
/* Local Typedefs */
/******************/

/* Callback info for sieve buffer readvv operation */
typedef struct H5D_contig_readvv_sieve_ud_t {
    H5F_t *file;                /* File for dataset */
    H5D_rdcdc_t *dset_contig;   /* Cached information about contiguous data */
    const H5D_contig_storage_t *store_contig;    /* Contiguous storage info for this I/O operation */
    unsigned char *rbuf;        /* Pointer to buffer to fill */
    hid_t dxpl_id;              /* DXPL for operation */
} H5D_contig_readvv_sieve_ud_t;

/* Callback info for [plain] readvv operation */
typedef struct H5D_contig_readvv_ud_t {
    H5F_t *file;                /* File for dataset */
    haddr_t dset_addr;          /* Address of dataset */
    unsigned char *rbuf;        /* Pointer to buffer to fill */
    hid_t dxpl_id;              /* DXPL for operation */
} H5D_contig_readvv_ud_t;

/* Callback info for sieve buffer writevv operation */
typedef struct H5D_contig_writevv_sieve_ud_t {
    H5F_t *file;                /* File for dataset */
    H5D_rdcdc_t *dset_contig;   /* Cached information about contiguous data */
    const H5D_contig_storage_t *store_contig;    /* Contiguous storage info for this I/O operation */
    const unsigned char *wbuf;  /* Pointer to buffer to write */
    hid_t dxpl_id;              /* DXPL for operation */
} H5D_contig_writevv_sieve_ud_t;

/* Callback info for [plain] writevv operation */
typedef struct H5D_contig_writevv_ud_t {
    H5F_t *file;                /* File for dataset */
    haddr_t dset_addr;          /* Address of dataset */
    const unsigned char *wbuf;  /* Pointer to buffer to write */
    hid_t dxpl_id;              /* DXPL for operation */
} H5D_contig_writevv_ud_t;


/********************/
/* Local Prototypes */
/********************/

/* Layout operation callbacks */
static herr_t H5D__contig_construct(H5F_t *f, H5D_t *dset);
static herr_t H5D__contig_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);
static ssize_t H5D__contig_readvv(const H5D_io_info_t *io_info,
    size_t dset_max_nseq, size_t *dset_curr_seq, size_t dset_len_arr[], hsize_t dset_offset_arr[],
    size_t mem_max_nseq, size_t *mem_curr_seq, size_t mem_len_arr[], hsize_t mem_offset_arr[]);
static ssize_t H5D__contig_writevv(const H5D_io_info_t *io_info,
    size_t dset_max_nseq, size_t *dset_curr_seq, size_t dset_len_arr[], hsize_t dset_offset_arr[],
    size_t mem_max_nseq, size_t *mem_curr_seq, size_t mem_len_arr[], hsize_t mem_offset_arr[]);
static herr_t H5D__contig_flush(H5D_t *dset, hid_t dxpl_id);

/* Helper routines */
static herr_t H5D__contig_write_one(H5D_io_info_t *io_info, hsize_t offset,
    size_t size);


/*********************/
/* Package Variables */
/*********************/

/* Contiguous storage layout I/O ops */
const H5D_layout_ops_t H5D_LOPS_CONTIG[1] = {{
    H5D__contig_construct,
    NULL,
    H5D__contig_is_space_alloc,
    H5D__contig_io_init,
    H5D__contig_read,
    H5D__contig_write,
#ifdef H5_HAVE_PARALLEL
    H5D__contig_collective_read,
    H5D__contig_collective_write,
#endif /* H5_HAVE_PARALLEL */
    H5D__contig_readvv,
    H5D__contig_writevv,
    H5D__contig_flush,
    NULL
}};


/*******************/
/* Local Variables */
/*******************/

/* Declare a PQ free list to manage the sieve buffer information */
H5FL_BLK_DEFINE(sieve_buf);

/* Declare extern the free list to manage blocks of type conversion data */
H5FL_BLK_EXTERN(type_conv);



/*-------------------------------------------------------------------------
 * Function:	H5D__contig_alloc
 *
 * Purpose:	Allocate file space for a contiguously stored dataset
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Quincey Koziol
 *		April 19, 2003
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5D__contig_alloc(H5F_t *f, hid_t dxpl_id, H5O_storage_contig_t *storage /*out */ )
{
    herr_t ret_value = SUCCEED;   /* Return value */

    FUNC_ENTER_PACKAGE

    /* check args */
    HDassert(f);
    HDassert(storage);

    /* Allocate space for the contiguous data */
    if(HADDR_UNDEF == (storage->addr = H5MF_alloc(f, H5FD_MEM_DRAW, dxpl_id, storage->size)))
        HGOTO_ERROR(H5E_IO, H5E_NOSPACE, FAIL, "unable to reserve file space")

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D__contig_alloc */


/*-------------------------------------------------------------------------
 * Function:	H5D__contig_fill
 *
 * Purpose:	Write fill values to a contiguously stored dataset.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Quincey Koziol
 *		August 22, 2002
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5D__contig_fill(const H5D_t *dset, hid_t dxpl_id)
{
    H5D_io_info_t ioinfo;       /* Dataset I/O info */
    H5D_storage_t store;        /* Union of storage info for dataset */
    H5D_dxpl_cache_t _dxpl_cache;       /* Data transfer property cache buffer */
    H5D_dxpl_cache_t *dxpl_cache = &_dxpl_cache;   /* Data transfer property cache */
    hssize_t    snpoints;       /* Number of points in space (for error checking) */
    size_t      npoints;        /* Number of points in space */
    hsize_t	offset;         /* Offset of dataset */
#ifdef H5_HAVE_PARALLEL
    MPI_Comm	mpi_comm = MPI_COMM_NULL;	/* MPI communicator for file */
    int         mpi_rank = (-1);  /* This process's rank  */
    int         mpi_code;       /* MPI return code */
    hbool_t     blocks_written = FALSE; /* Flag to indicate that chunk was actually written */
    hbool_t     using_mpi = FALSE;      /* Flag to indicate that the file is being accessed with an MPI-capable file driver */
#endif /* H5_HAVE_PARALLEL */
    H5D_fill_buf_info_t fb_info;        /* Dataset's fill buffer info */
    hbool_t     fb_info_init = FALSE;   /* Whether the fill value buffer has been initialized */
    hid_t       my_dxpl_id;     /* DXPL ID to use for this operation */
    herr_t	ret_value = SUCCEED;	/* Return value */

    FUNC_ENTER_PACKAGE

    /* Check args */
    HDassert(TRUE == H5P_isa_class(dxpl_id, H5P_DATASET_XFER));
    HDassert(dset && H5D_CONTIGUOUS == dset->shared->layout.type);
    HDassert(H5F_addr_defined(dset->shared->layout.storage.u.contig.addr));
    HDassert(dset->shared->layout.storage.u.contig.size > 0);
    HDassert(dset->shared->space);
    HDassert(dset->shared->type);

#ifdef H5_HAVE_PARALLEL
    /* Retrieve MPI parameters */
    if(H5F_HAS_FEATURE(dset->oloc.file, H5FD_FEAT_HAS_MPI)) {
        /* Get the MPI communicator */
        if(MPI_COMM_NULL == (mpi_comm = H5F_mpi_get_comm(dset->oloc.file)))
            HGOTO_ERROR(H5E_INTERNAL, H5E_MPI, FAIL, "Can't retrieve MPI communicator")

        /* Get the MPI rank */
        if((mpi_rank = H5F_mpi_get_rank(dset->oloc.file)) < 0)
            HGOTO_ERROR(H5E_INTERNAL, H5E_MPI, FAIL, "Can't retrieve MPI rank")

        /* Set the MPI-capable file driver flag */
        using_mpi = TRUE;

        /* Use the internal "independent" DXPL */
        my_dxpl_id = H5AC_ind_dxpl_id;
    } /* end if */
    else {
#endif  /* H5_HAVE_PARALLEL */
        /* Use the DXPL we were given */
        my_dxpl_id = dxpl_id;
#ifdef H5_HAVE_PARALLEL
    } /* end else */
#endif  /* H5_HAVE_PARALLEL */

    /* Fill the DXPL cache values for later use */
    if(H5D__get_dxpl_cache(my_dxpl_id, &dxpl_cache) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't fill dxpl cache")

    /* Initialize storage info for this dataset */
    store.contig.dset_addr = dset->shared->layout.storage.u.contig.addr;
    store.contig.dset_size = dset->shared->layout.storage.u.contig.size;

    /* Get the number of elements in the dataset's dataspace */
    if((snpoints = H5S_GET_EXTENT_NPOINTS(dset->shared->space)) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "dataset has negative number of elements")
    H5_CHECKED_ASSIGN(npoints, size_t, snpoints, hssize_t);

    /* Initialize the fill value buffer */
    if(H5D__fill_init(&fb_info, NULL, NULL, NULL, NULL, NULL,
            &dset->shared->dcpl_cache.fill,
            dset->shared->type, dset->shared->type_id, npoints,
            dxpl_cache->max_temp_buf, my_dxpl_id) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "can't initialize fill buffer info")
    fb_info_init = TRUE;

    /* Start at the beginning of the dataset */
    offset = 0;

    /* Simple setup for dataset I/O info struct */
    H5D_BUILD_IO_INFO_WRT(&ioinfo, dset, dxpl_cache, my_dxpl_id, &store, fb_info.fill_buf);

    /*
     * Fill the entire current extent with the fill value.  We can do
     * this quite efficiently by making sure we copy the fill value
     * in relatively large pieces.
     */

    /* Loop through writing the fill value to the dataset */
    while(npoints > 0) {
        size_t curr_points;     /* Number of elements to write on this iteration of the loop */
        size_t size;            /* Size of buffer to write */

        /* Compute # of elements and buffer size to write for this iteration */
        curr_points = MIN(fb_info.elmts_per_buf, npoints);
        size = curr_points * fb_info.file_elmt_size;

        /* Check for VL datatype & non-default fill value */
        if(fb_info.has_vlen_fill_type)
            /* Re-fill the buffer to use for this I/O operation */
            if(H5D__fill_refill_vl(&fb_info, curr_points, my_dxpl_id) < 0)
                HGOTO_ERROR(H5E_DATASET, H5E_CANTCONVERT, FAIL, "can't refill fill value buffer")

#ifdef H5_HAVE_PARALLEL
            /* Check if this file is accessed with an MPI-capable file driver */
            if(using_mpi) {
                /* Write the chunks out from only one process */
                /* !! Use the internal "independent" DXPL!! -QAK */
                if(H5_PAR_META_WRITE == mpi_rank)
                    if(H5D__contig_write_one(&ioinfo, offset, size) < 0)
                        HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to write fill value to dataset")

                /* Indicate that blocks are being written */
                blocks_written = TRUE;
            } /* end if */
            else {
#endif /* H5_HAVE_PARALLEL */
                H5_CHECK_OVERFLOW(size, size_t, hsize_t);
                if(H5D__contig_write_one(&ioinfo, offset, size) < 0)
                    HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to write fill value to dataset")
#ifdef H5_HAVE_PARALLEL
            } /* end else */
#endif /* H5_HAVE_PARALLEL */

          npoints -= curr_points;
          offset += size;
      } /* end while */

#ifdef H5_HAVE_PARALLEL
    /* Only need to block at the barrier if we actually wrote fill values */
    /* And if we are using an MPI-capable file driver */
    if(using_mpi && blocks_written) {
        /* Wait at barrier to avoid race conditions where some processes are
         * still writing out fill values and other processes race ahead to data
         * in, getting bogus data.
         */
        if(MPI_SUCCESS != (mpi_code = MPI_Barrier(mpi_comm)))
            HMPI_GOTO_ERROR(FAIL, "MPI_Barrier failed", mpi_code)
    } /* end if */
#endif /* H5_HAVE_PARALLEL */

done:
    /* Release the fill buffer info, if it's been initialized */
    if(fb_info_init && H5D__fill_term(&fb_info) < 0)
        HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "Can't release fill buffer info")

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D__contig_fill() */


/*-------------------------------------------------------------------------
 * Function:	H5D__contig_delete
 *
 * Purpose:	Delete the file space for a contiguously stored dataset
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Quincey Koziol
 *		March 20, 2003
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5D__contig_delete(H5F_t *f, hid_t dxpl_id, const H5O_storage_t *storage)
{
    herr_t ret_value = SUCCEED;   /* Return value */

    FUNC_ENTER_PACKAGE

    /* check args */
    HDassert(f);
    HDassert(storage);

    /* Free the file space for the chunk */
    if(H5MF_xfree(f, H5FD_MEM_DRAW, dxpl_id, storage->u.contig.addr, storage->u.contig.size) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "unable to free contiguous storage space")

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D__contig_delete */


/*-------------------------------------------------------------------------
 * Function:	H5D__contig_construct
 *
 * Purpose:	Constructs new contiguous layout information for dataset
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Quincey Koziol
 *              Thursday, May 22, 2008
 *
 *-------------------------------------------------------------------------
 */
/* ARGSUSED */
static herr_t
H5D__contig_construct(H5F_t *f, H5D_t *dset)
{
    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 */
    hsize_t tmp_size;                   /* Temporary holder for raw data size */
    size_t tmp_sieve_buf_size;          /* Temporary holder for sieve buffer size */
    hsize_t dim[H5O_LAYOUT_NDIMS];	/* Current size of data in elements */
    hsize_t max_dim[H5O_LAYOUT_NDIMS];  /* Maximum size of data in elements */
    int ndims;                          /* Rank of dataspace */
    int i;                              /* Local index variable */
    herr_t ret_value = SUCCEED;         /* Return value */

    FUNC_ENTER_STATIC

    /* Sanity checks */
    HDassert(f);
    HDassert(dset);

    /*
     * The maximum size of the dataset cannot exceed the storage size.
     * Also, only the slowest varying dimension of a simple data space
     * can be extendible (currently only for external data storage).
     */

    /* Check for invalid dataset dimensions */
    if((ndims = H5S_get_simple_extent_dims(dset->shared->space, dim, max_dim)) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to initialize contiguous storage")
    for(i = 0; i < ndims; i++)
        if(max_dim[i] > dim[i])
            HGOTO_ERROR(H5E_DATASET, H5E_UNSUPPORTED, FAIL, "extendible contiguous non-external dataset")

    /* Retrieve the number of elements in the dataspace */
    if((snelmts = H5S_GET_EXTENT_NPOINTS(dset->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(dset->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 */
    dset->shared->layout.storage.u.contig.size = tmp_size;

    /* Get the sieve buffer size for the file */
    tmp_sieve_buf_size = H5F_SIEVE_BUF_SIZE(f);

    /* 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)
        dset->shared->cache.contig.sieve_buf_size = tmp_size;
    else
        dset->shared->cache.contig.sieve_buf_size = tmp_sieve_buf_size;

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D__contig_construct() */


/*-------------------------------------------------------------------------
 * Function:	H5D__contig_is_space_alloc
 *
 * Purpose:	Query if space is allocated for layout
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Quincey Koziol
 *              Thursday, January 15, 2009
 *
 *-------------------------------------------------------------------------
 */
hbool_t
H5D__contig_is_space_alloc(const H5O_storage_t *storage)
{
    hbool_t ret_value;                  /* Return value */

    FUNC_ENTER_PACKAGE_NOERR

    /* Sanity checks */
    HDassert(storage);

    /* Set return value */
    ret_value = (hbool_t)H5F_addr_defined(storage->u.contig.addr);

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D__contig_is_space_alloc() */


/*-------------------------------------------------------------------------
 * Function:	H5D__contig_io_init
 *
 * Purpose:	Performs initialization before any sort of I/O on the raw data
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Quincey Koziol
 *              Thursday, March 20, 2008
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5D__contig_io_init(const H5D_io_info_t *io_info, const H5D_type_info_t H5_ATTR_UNUSED *type_info,
    hsize_t H5_ATTR_UNUSED nelmts, const H5S_t H5_ATTR_UNUSED *file_space, const H5S_t H5_ATTR_UNUSED *mem_space,
    H5D_chunk_map_t H5_ATTR_UNUSED *cm)
{
    FUNC_ENTER_STATIC_NOERR

    io_info->store->contig.dset_addr = io_info->dset->shared->layout.storage.u.contig.addr;
    io_info->store->contig.dset_size = io_info->dset->shared->layout.storage.u.contig.size;

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* end H5D__contig_io_init() */


/*-------------------------------------------------------------------------
 * Function:	H5D__contig_read
 *
 * Purpose:	Read from a contiguous dataset.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Raymond Lu
 *		Thursday, April 10, 2003
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5D__contig_read(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 H5_ATTR_UNUSED *fm)
{
    herr_t	ret_value = SUCCEED;	/*return value		*/

    FUNC_ENTER_PACKAGE

    /* Sanity check */
    HDassert(io_info);
    HDassert(io_info->u.rbuf);
    HDassert(type_info);
    HDassert(mem_space);
    HDassert(file_space);

    /* Read data */
    if((io_info->io_ops.single_read)(io_info, type_info, nelmts, file_space, mem_space) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_READERROR, FAIL, "contiguous read failed")

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D__contig_read() */


/*-------------------------------------------------------------------------
 * Function:	H5D__contig_write
 *
 * Purpose:	Write to a contiguous dataset.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Raymond Lu
 *		Thursday, April 10, 2003
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5D__contig_write(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 H5_ATTR_UNUSED *fm)
{
    herr_t	ret_value = SUCCEED;	/*return value		*/

    FUNC_ENTER_PACKAGE

    /* Sanity check */
    HDassert(io_info);
    HDassert(io_info->u.wbuf);
    HDassert(type_info);
    HDassert(mem_space);
    HDassert(file_space);

    /* Write data */
    if((io_info->io_ops.single_write)(io_info, type_info, nelmts, file_space, mem_space) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_WRITEERROR, FAIL, "contiguous write failed")

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D__contig_write() */


/*-------------------------------------------------------------------------
 * Function:	H5D__contig_write_one
 *
 * Purpose:	Writes some data from a dataset into a buffer.
 *		The data is contiguous.	 The address is relative to the base
 *		address for the file.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Quincey Koziol
 *              Thursday, September 28, 2000
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5D__contig_write_one(H5D_io_info_t *io_info, hsize_t offset, size_t size)
{
    hsize_t dset_off = offset;  /* Offset in dataset */
    size_t dset_len = size;     /* Length in dataset */
    size_t dset_curr_seq = 0;   /* "Current sequence" in dataset */
    hsize_t mem_off = 0;        /* Offset in memory */
    size_t mem_len = size;      /* Length in memory */
    size_t mem_curr_seq = 0;    /* "Current sequence" in memory */
    herr_t ret_value = SUCCEED; /* Return value */

    FUNC_ENTER_STATIC

    HDassert(io_info);

    if(H5D__contig_writevv(io_info, (size_t)1, &dset_curr_seq, &dset_len, &dset_off,
            (size_t)1, &mem_curr_seq, &mem_len, &mem_off) < 0)
        HGOTO_ERROR(H5E_IO, H5E_WRITEERROR, FAIL, "vector write failed")

done:
    FUNC_LEAVE_NOAPI(ret_value)
}   /* end H5D__contig_write_one() */


/*-------------------------------------------------------------------------
 * Function:	H5D__contig_readvv_sieve_cb
 *
 * Purpose:	Callback operator for H5D__contig_readvv() with sieve buffer.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Quincey Koziol
 *              Thursday, Sept 30, 2010
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5D__contig_readvv_sieve_cb(hsize_t dst_off, hsize_t src_off, size_t len,
    void *_udata)
{
    H5D_contig_readvv_sieve_ud_t *udata = (H5D_contig_readvv_sieve_ud_t *)_udata; /* User data for H5VM_opvv() operator */
    H5F_t *file = udata->file;        /* File for dataset */
    H5D_rdcdc_t *dset_contig = udata->dset_contig; /* Cached information about contiguous data */
    const H5D_contig_storage_t *store_contig = udata->store_contig;    /* Contiguous storage info for this I/O operation */
    unsigned char *buf;         /* Pointer to buffer to fill */
    haddr_t addr;               /* Actual address to read */
    haddr_t sieve_start = HADDR_UNDEF, sieve_end = HADDR_UNDEF;     /* Start & end locations of sieve buffer */
    haddr_t contig_end;         /* End locations of block to write */
    size_t sieve_size = (size_t)-1;   /* Size of sieve buffer */
    haddr_t rel_eoa;	        /* Relative end of file address	*/
    hsize_t max_data;           /* Actual maximum size of data to cache */
    hsize_t min;                /* temporary minimum value (avoids some ugly macro nesting) */
    herr_t ret_value = SUCCEED; /* Return value */

    FUNC_ENTER_STATIC

    /* Stash local copies of these value */
    if(dset_contig->sieve_buf != NULL) {
        sieve_start = dset_contig->sieve_loc;
        sieve_size = dset_contig->sieve_size;
        sieve_end = sieve_start + sieve_size;
    } /* end if */

    /* Compute offset on disk */
    addr = store_contig->dset_addr + dst_off;

    /* Compute offset in memory */
    buf = udata->rbuf + src_off;

    /* Check if the sieve buffer is allocated yet */
    if(NULL == dset_contig->sieve_buf) {
        /* Check if we can actually hold the I/O request in the sieve buffer */
        if(len > dset_contig->sieve_buf_size) {
            if(H5F_block_read(file, H5FD_MEM_DRAW, addr, len, udata->dxpl_id, buf) < 0)
                HGOTO_ERROR(H5E_DATASET, H5E_READERROR, FAIL, "block read failed")
        } /* end if */
        else {
            /* Allocate room for the data sieve buffer */
            if(NULL == (dset_contig->sieve_buf = H5FL_BLK_CALLOC(sieve_buf, dset_contig->sieve_buf_size)))
                HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "memory allocation failed")

            /* Determine the new sieve buffer size & location */
            dset_contig->sieve_loc = addr;

            /* Make certain we don't read off the end of the file */
            if(HADDR_UNDEF == (rel_eoa = H5F_get_eoa(file, H5FD_MEM_DRAW)))
                HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "unable to determine file size")

            /* Set up the buffer parameters */
            max_data = store_contig->dset_size - dst_off;

            /* Compute the size of the sieve buffer */
            min = MIN3(rel_eoa - dset_contig->sieve_loc, max_data, dset_contig->sieve_buf_size);
            H5_CHECKED_ASSIGN(dset_contig->sieve_size, size_t, min, hsize_t);

            /* Read the new sieve buffer */
            if(H5F_block_read(file, H5FD_MEM_DRAW, dset_contig->sieve_loc, dset_contig->sieve_size, udata->dxpl_id, dset_contig->sieve_buf) < 0)
                HGOTO_ERROR(H5E_DATASET, H5E_READERROR, FAIL, "block read failed")

            /* Grab the data out of the buffer (must be first piece of data in buffer ) */
            HDmemcpy(buf, dset_contig->sieve_buf, len);

            /* Reset sieve buffer dirty flag */
            dset_contig->sieve_dirty = FALSE;

            /* Stash local copies of these value */
            sieve_start = dset_contig->sieve_loc;
            sieve_size = dset_contig->sieve_size;
            sieve_end = sieve_start+sieve_size;
        } /* end else */
    } /* end if */
    else {
        /* Compute end of sequence to retrieve */
        contig_end = addr + len - 1;

        /* If entire read is within the sieve buffer, read it from the buffer */
        if(addr >= sieve_start && contig_end < sieve_end) {
            unsigned char *base_sieve_buf = dset_contig->sieve_buf + (addr - sieve_start);

            /* Grab the data out of the buffer */
            HDmemcpy(buf, base_sieve_buf, len);
        } /* end if */
        /* Entire request is not within this data sieve buffer */
        else {
            /* Check if we can actually hold the I/O request in the sieve buffer */
            if(len > dset_contig->sieve_buf_size) {
                /* Check for any overlap with the current sieve buffer */
                if((sieve_start >= addr && sieve_start < (contig_end + 1))
                        || ((sieve_end - 1) >= addr && (sieve_end - 1) < (contig_end + 1))) {
                    /* Flush the sieve buffer, if it's dirty */
                    if(dset_contig->sieve_dirty) {
                        /* Write to file */
                        if(H5F_block_write(file, H5FD_MEM_DRAW, sieve_start, sieve_size, udata->dxpl_id, dset_contig->sieve_buf) < 0)
                            HGOTO_ERROR(H5E_DATASET, H5E_WRITEERROR, FAIL, "block write failed")

                        /* Reset sieve buffer dirty flag */
                        dset_contig->sieve_dirty = FALSE;
                    } /* end if */
                } /* end if */

                /* Read directly into the user's buffer */
                if(H5F_block_read(file, H5FD_MEM_DRAW, addr, len, udata->dxpl_id, buf) < 0)
                    HGOTO_ERROR(H5E_DATASET, H5E_READERROR, FAIL, "block read failed")
            } /* end if */
            /* Element size fits within the buffer size */
            else {
                /* Flush the sieve buffer if it's dirty */
                if(dset_contig->sieve_dirty) {
                    /* Write to file */
                    if(H5F_block_write(file, H5FD_MEM_DRAW, sieve_start, sieve_size, udata->dxpl_id, dset_contig->sieve_buf) < 0)
                        HGOTO_ERROR(H5E_DATASET, H5E_WRITEERROR, FAIL, "block write failed")

                    /* Reset sieve buffer dirty flag */
                    dset_contig->sieve_dirty = FALSE;
                } /* end if */

                /* Determine the new sieve buffer size & location */
                dset_contig->sieve_loc = addr;

                /* Make certain we don't read off the end of the file */
                if(HADDR_UNDEF == (rel_eoa = H5F_get_eoa(file, H5FD_MEM_DRAW)))
                    HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "unable to determine file size")

                /* Only need this when resizing sieve buffer */
                max_data = store_contig->dset_size - dst_off;

                /* Compute the size of the sieve buffer.
                 * Don't read off the end of the file, don't read past
                 * the end of the data element, and don't read more than
                 * the buffer size.
                 */
                min = MIN3(rel_eoa - dset_contig->sieve_loc, max_data, dset_contig->sieve_buf_size); 
                H5_CHECKED_ASSIGN(dset_contig->sieve_size, size_t, min, hsize_t);

                /* Update local copies of sieve information */
                sieve_start = dset_contig->sieve_loc;
                sieve_size = dset_contig->sieve_size;
                sieve_end = sieve_start + sieve_size;

                /* Read the new sieve buffer */
                if(H5F_block_read(file, H5FD_MEM_DRAW, dset_contig->sieve_loc, dset_contig->sieve_size, udata->dxpl_id, dset_contig->sieve_buf) < 0)
                    HGOTO_ERROR(H5E_DATASET, H5E_READERROR, FAIL, "block read failed")

                /* Grab the data out of the buffer (must be first piece of data in buffer ) */
                HDmemcpy(buf, dset_contig->sieve_buf, len);

                /* Reset sieve buffer dirty flag */
                dset_contig->sieve_dirty = FALSE;
            } /* end else */
        } /* end else */
    } /* end else */

done:
    FUNC_LEAVE_NOAPI(ret_value)
}   /* end H5D__contig_readvv_sieve_cb() */


/*-------------------------------------------------------------------------
 * Function:	H5D__contig_readvv_cb
 *
 * Purpose:	Callback operator for H5D__contig_readvv() without sieve buffer.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Quincey Koziol
 *              Thursday, Sept 30, 2010
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5D__contig_readvv_cb(hsize_t dst_off, hsize_t src_off, size_t len, void *_udata)
{
    H5D_contig_readvv_ud_t *udata = (H5D_contig_readvv_ud_t *)_udata; /* User data for H5VM_opvv() operator */
    herr_t ret_value = SUCCEED;         /* Return value */

    FUNC_ENTER_STATIC

    /* Write data */
    if(H5F_block_read(udata->file, H5FD_MEM_DRAW, (udata->dset_addr + dst_off),
            len, udata->dxpl_id, (udata->rbuf + src_off)) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_WRITEERROR, FAIL, "block write failed")

done:
    FUNC_LEAVE_NOAPI(ret_value)
}   /* end H5D__contig_readvv_cb() */


/*-------------------------------------------------------------------------
 * Function:	H5D__contig_readvv
 *
 * Purpose:	Reads some data vectors from a dataset into a buffer.
 *		The data is contiguous.	 The address is the start of the dataset,
 *              relative to the base address for the file and the offsets and
 *              sequence lengths are in bytes.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Quincey Koziol
 *              Friday, May 3, 2001
 *
 * Notes:
 *      Offsets in the sequences must be monotonically increasing
 *
 *-------------------------------------------------------------------------
 */
static ssize_t
H5D__contig_readvv(const H5D_io_info_t *io_info,
    size_t dset_max_nseq, size_t *dset_curr_seq, size_t dset_len_arr[], hsize_t dset_off_arr[],
    size_t mem_max_nseq, size_t *mem_curr_seq, size_t mem_len_arr[], hsize_t mem_off_arr[])
{
    ssize_t ret_value;          /* Return value */

    FUNC_ENTER_STATIC

    /* Check args */
    HDassert(io_info);
    HDassert(dset_curr_seq);
    HDassert(dset_len_arr);
    HDassert(dset_off_arr);
    HDassert(mem_curr_seq);
    HDassert(mem_len_arr);
    HDassert(mem_off_arr);

    /* Check if data sieving is enabled */
    if(H5F_HAS_FEATURE(io_info->dset->oloc.file, H5FD_FEAT_DATA_SIEVE)) {
        H5D_contig_readvv_sieve_ud_t udata;     /* User data for H5VM_opvv() operator */

        /* Set up user data for H5VM_opvv() */
        udata.file = io_info->dset->oloc.file;
        udata.dset_contig = &(io_info->dset->shared->cache.contig);
        udata.store_contig = &(io_info->store->contig);
        udata.rbuf = (unsigned char *)io_info->u.rbuf;
        udata.dxpl_id = io_info->dxpl_id;

        /* Call generic sequence operation routine */
        if((ret_value = H5VM_opvv(dset_max_nseq, dset_curr_seq, dset_len_arr, dset_off_arr,
                mem_max_nseq, mem_curr_seq, mem_len_arr, mem_off_arr,
                H5D__contig_readvv_sieve_cb, &udata)) < 0)
            HGOTO_ERROR(H5E_DATASET, H5E_CANTOPERATE, FAIL, "can't perform vectorized sieve buffer read")
    } /* end if */
    else {
        H5D_contig_readvv_ud_t udata;     /* User data for H5VM_opvv() operator */

        /* Set up user data for H5VM_opvv() */
        udata.file = io_info->dset->oloc.file;
        udata.dset_addr = io_info->store->contig.dset_addr;
        udata.rbuf = (unsigned char *)io_info->u.rbuf;
        udata.dxpl_id = io_info->dxpl_id;

        /* Call generic sequence operation routine */
        if((ret_value = H5VM_opvv(dset_max_nseq, dset_curr_seq, dset_len_arr, dset_off_arr,
                mem_max_nseq, mem_curr_seq, mem_len_arr, mem_off_arr,
                H5D__contig_readvv_cb, &udata)) < 0)
            HGOTO_ERROR(H5E_DATASET, H5E_CANTOPERATE, FAIL, "can't perform vectorized read")
    } /* end else */

done:
    FUNC_LEAVE_NOAPI(ret_value)
}   /* end H5D__contig_readvv() */


/*-------------------------------------------------------------------------
 * Function:	H5D__contig_writevv_sieve_cb
 *
 * Purpose:	Callback operator for H5D__contig_writevv() with sieve buffer.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Quincey Koziol
 *              Thursday, Sept 30, 2010
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5D__contig_writevv_sieve_cb(hsize_t dst_off, hsize_t src_off, size_t len,
    void *_udata)
{
    H5D_contig_writevv_sieve_ud_t *udata = (H5D_contig_writevv_sieve_ud_t *)_udata; /* User data for H5VM_opvv() operator */
    H5F_t *file = udata->file;        /* File for dataset */
    H5D_rdcdc_t *dset_contig = udata->dset_contig; /* Cached information about contiguous data */
    const H5D_contig_storage_t *store_contig = udata->store_contig;    /* Contiguous storage info for this I/O operation */
    const unsigned char *buf;   /* Pointer to buffer to fill */
    haddr_t addr;               /* Actual address to read */
    haddr_t sieve_start = HADDR_UNDEF, sieve_end = HADDR_UNDEF;     /* Start & end locations of sieve buffer */
    haddr_t contig_end;         /* End locations of block to write */
    size_t sieve_size = (size_t)-1; /* size of sieve buffer */
    haddr_t rel_eoa;	        /* Relative end of file address	*/
    hsize_t max_data;           /* Actual maximum size of data to cache */
    hsize_t min;                /* temporary minimum value (avoids some ugly macro nesting) */
    herr_t ret_value = SUCCEED; /* Return value */

    FUNC_ENTER_STATIC

    /* Stash local copies of these values */
    if(dset_contig->sieve_buf != NULL) {
        sieve_start = dset_contig->sieve_loc;
        sieve_size = dset_contig->sieve_size;
        sieve_end = sieve_start + sieve_size;
    } /* end if */

    /* Compute offset on disk */
    addr = store_contig->dset_addr + dst_off;

    /* Compute offset in memory */
    buf = udata->wbuf + src_off;

    /* No data sieve buffer yet, go allocate one */
    if(NULL == dset_contig->sieve_buf) {
        /* Check if we can actually hold the I/O request in the sieve buffer */
        if(len > dset_contig->sieve_buf_size) {
            if(H5F_block_write(file, H5FD_MEM_DRAW, addr, len, udata->dxpl_id, buf) < 0)
                HGOTO_ERROR(H5E_DATASET, H5E_WRITEERROR, FAIL, "block write failed")
        } /* end if */
        else {
            /* Allocate room for the data sieve buffer */
            if(NULL == (dset_contig->sieve_buf = H5FL_BLK_CALLOC(sieve_buf, dset_contig->sieve_buf_size)))
                HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "memory allocation failed")

#ifdef H5_CLEAR_MEMORY
if(dset_contig->sieve_size > len)
    HDmemset(dset_contig->sieve_buf + len, 0, (dset_contig->sieve_size - len));
#endif /* H5_CLEAR_MEMORY */

            /* Determine the new sieve buffer size & location */
            dset_contig->sieve_loc = addr;

            /* Make certain we don't read off the end of the file */
            if(HADDR_UNDEF == (rel_eoa = H5F_get_eoa(file, H5FD_MEM_DRAW)))
                HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "unable to determine file size")

            /* Set up the buffer parameters */
            max_data = store_contig->dset_size - dst_off;

            /* Compute the size of the sieve buffer */
            min = MIN3(rel_eoa - dset_contig->sieve_loc, max_data, dset_contig->sieve_buf_size); 
            H5_CHECKED_ASSIGN(dset_contig->sieve_size, size_t, min, hsize_t);

            /* Check if there is any point in reading the data from the file */
            if(dset_contig->sieve_size > len) {
                /* Read the new sieve buffer */
                if(H5F_block_read(file, H5FD_MEM_DRAW, dset_contig->sieve_loc, dset_contig->sieve_size, udata->dxpl_id, dset_contig->sieve_buf) < 0)
                    HGOTO_ERROR(H5E_DATASET, H5E_READERROR, FAIL, "block read failed")
            } /* end if */

            /* Grab the data out of the buffer (must be first piece of data in buffer ) */
            HDmemcpy(dset_contig->sieve_buf, buf, len);

            /* Set sieve buffer dirty flag */
            dset_contig->sieve_dirty = TRUE;

            /* Stash local copies of these values */
            sieve_start = dset_contig->sieve_loc;
            sieve_size = dset_contig->sieve_size;
            sieve_end = sieve_start + sieve_size;
        } /* end else */
    } /* end if */
    else {
        /* Compute end of sequence to retrieve */
        contig_end = addr + len - 1;

        /* If entire write is within the sieve buffer, write it to the buffer */
        if(addr >= sieve_start && contig_end < sieve_end) {
            unsigned char *base_sieve_buf = dset_contig->sieve_buf + (addr - sieve_start);

            /* Put the data into the sieve buffer */
            HDmemcpy(base_sieve_buf, buf, len);

            /* Set sieve buffer dirty flag */
            dset_contig->sieve_dirty = TRUE;
        } /* end if */
        /* Entire request is not within this data sieve buffer */
        else {
            /* Check if we can actually hold the I/O request in the sieve buffer */
            if(len > dset_contig->sieve_buf_size) {
                /* Check for any overlap with the current sieve buffer */
                if((sieve_start >= addr && sieve_start < (contig_end + 1))
                        || ((sieve_end - 1) >= addr && (sieve_end - 1) < (contig_end + 1))) {
                    /* Flush the sieve buffer, if it's dirty */
                    if(dset_contig->sieve_dirty) {
                        /* Write to file */
                        if(H5F_block_write(file, H5FD_MEM_DRAW, sieve_start, sieve_size, udata->dxpl_id, dset_contig->sieve_buf) < 0)
                            HGOTO_ERROR(H5E_DATASET, H5E_WRITEERROR, FAIL, "block write failed")

                        /* Reset sieve buffer dirty flag */
                        dset_contig->sieve_dirty = FALSE;
                    } /* end if */

                    /* Force the sieve buffer to be re-read the next time */
                    dset_contig->sieve_loc = HADDR_UNDEF;
                    dset_contig->sieve_size = 0;
                } /* end if */

                /* Write directly from the user's buffer */
                if(H5F_block_write(file, H5FD_MEM_DRAW, addr, len, udata->dxpl_id, buf) < 0)
                    HGOTO_ERROR(H5E_DATASET, H5E_WRITEERROR, FAIL, "block write failed")
            } /* end if */
            /* Element size fits within the buffer size */
            else {
                /* Check if it is possible to (exactly) prepend or append to existing (dirty) sieve buffer */
                if(((addr + len) == sieve_start || addr == sieve_end) &&
                        (len + sieve_size) <= dset_contig->sieve_buf_size &&
                        dset_contig->sieve_dirty) {
                    /* Prepend to existing sieve buffer */
                    if((addr + len) == sieve_start) {
                        /* Move existing sieve information to correct location */
                        HDmemmove(dset_contig->sieve_buf + len, dset_contig->sieve_buf, dset_contig->sieve_size);

                        /* Copy in new information (must be first in sieve buffer) */
                        HDmemcpy(dset_contig->sieve_buf, buf, len);

                        /* Adjust sieve location */
                        dset_contig->sieve_loc = addr;

                    } /* end if */
                    /* Append to existing sieve buffer */
                    else {
                        /* Copy in new information */
                        HDmemcpy(dset_contig->sieve_buf + sieve_size, buf, len);
                    } /* end else */

                    /* Adjust sieve size */
                    dset_contig->sieve_size += len;

                    /* Update local copies of sieve information */
                    sieve_start = dset_contig->sieve_loc;
                    sieve_size = dset_contig->sieve_size;
                    sieve_end = sieve_start + sieve_size;
                } /* end if */
                /* Can't add the new data onto the existing sieve buffer */
                else {
                    /* Flush the sieve buffer if it's dirty */
                    if(dset_contig->sieve_dirty) {
                        /* Write to file */
                        if(H5F_block_write(file, H5FD_MEM_DRAW, sieve_start, sieve_size, udata->dxpl_id, dset_contig->sieve_buf) < 0)
                            HGOTO_ERROR(H5E_DATASET, H5E_WRITEERROR, FAIL, "block write failed")

                        /* Reset sieve buffer dirty flag */
                        dset_contig->sieve_dirty = FALSE;
                    } /* end if */

                    /* Determine the new sieve buffer size & location */
                    dset_contig->sieve_loc = addr;

                    /* Make certain we don't read off the end of the file */
                    if(HADDR_UNDEF == (rel_eoa = H5F_get_eoa(file, H5FD_MEM_DRAW)))
                        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "unable to determine file size")

                    /* Only need this when resizing sieve buffer */
                    max_data = store_contig->dset_size - dst_off;

                    /* Compute the size of the sieve buffer.
                     * Don't read off the end of the file, don't read past
                     * the end of the data element, and don't read more than
                     * the buffer size.
                     */
                    min = MIN3(rel_eoa - dset_contig->sieve_loc, max_data, dset_contig->sieve_buf_size); 
                    H5_CHECKED_ASSIGN(dset_contig->sieve_size, size_t, min, hsize_t);

                    /* Update local copies of sieve information */
                    sieve_start = dset_contig->sieve_loc;
                    sieve_size = dset_contig->sieve_size;
                    sieve_end = sieve_start + sieve_size;

                    /* Check if there is any point in reading the data from the file */
                    if(dset_contig->sieve_size > len) {
                        /* Read the new sieve buffer */
                        if(H5F_block_read(file, H5FD_MEM_DRAW, dset_contig->sieve_loc, dset_contig->sieve_size, udata->dxpl_id, dset_contig->sieve_buf) < 0)
                            HGOTO_ERROR(H5E_DATASET, H5E_READERROR, FAIL, "block read failed")
                    } /* end if */

                    /* Grab the data out of the buffer (must be first piece of data in buffer ) */
                    HDmemcpy(dset_contig->sieve_buf, buf, len);

                    /* Set sieve buffer dirty flag */
                    dset_contig->sieve_dirty = TRUE;
                } /* end else */
            } /* end else */
        } /* end else */
    } /* end else */

done:
    FUNC_LEAVE_NOAPI(ret_value)
}   /* end H5D__contig_writevv_sieve_cb() */


/*-------------------------------------------------------------------------
 * Function:	H5D__contig_writevv_cb
 *
 * Purpose:	Callback operator for H5D__contig_writevv().
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Quincey Koziol
 *              Thursday, Sept 30, 2010
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5D__contig_writevv_cb(hsize_t dst_off, hsize_t src_off, size_t len, void *_udata)
{
    H5D_contig_writevv_ud_t *udata = (H5D_contig_writevv_ud_t *)_udata; /* User data for H5VM_opvv() operator */
    herr_t ret_value = SUCCEED; /* Return value */

    FUNC_ENTER_STATIC

    /* Write data */
    if(H5F_block_write(udata->file, H5FD_MEM_DRAW, (udata->dset_addr + dst_off), len, udata->dxpl_id, (udata->wbuf + src_off)) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_WRITEERROR, FAIL, "block write failed")

done:
    FUNC_LEAVE_NOAPI(ret_value)
}   /* end H5D__contig_writevv_cb() */


/*-------------------------------------------------------------------------
 * Function:	H5D__contig_writevv
 *
 * Purpose:	Writes some data vectors into a dataset from vectors into a
 *              buffer.  The address is the start of the dataset,
 *              relative to the base address for the file and the offsets and
 *              sequence lengths are in bytes.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Quincey Koziol
 *              Friday, May 2, 2003
 *
 * Notes:
 *      Offsets in the sequences must be monotonically increasing
 *
 *-------------------------------------------------------------------------
 */
static ssize_t
H5D__contig_writevv(const H5D_io_info_t *io_info,
    size_t dset_max_nseq, size_t *dset_curr_seq, size_t dset_len_arr[], hsize_t dset_off_arr[],
    size_t mem_max_nseq, size_t *mem_curr_seq, size_t mem_len_arr[], hsize_t mem_off_arr[])
{
    ssize_t ret_value;          /* Return value (Size of sequence in bytes) */

    FUNC_ENTER_STATIC

    /* Check args */
    HDassert(io_info);
    HDassert(dset_curr_seq);
    HDassert(dset_len_arr);
    HDassert(dset_off_arr);
    HDassert(mem_curr_seq);
    HDassert(mem_len_arr);
    HDassert(mem_off_arr);

    /* Check if data sieving is enabled */
    if(H5F_HAS_FEATURE(io_info->dset->oloc.file, H5FD_FEAT_DATA_SIEVE)) {
        H5D_contig_writevv_sieve_ud_t udata;    /* User data for H5VM_opvv() operator */

        /* Set up user data for H5VM_opvv() */
        udata.file = io_info->dset->oloc.file;
        udata.dset_contig = &(io_info->dset->shared->cache.contig);
        udata.store_contig = &(io_info->store->contig);
        udata.wbuf = (const unsigned char *)io_info->u.wbuf;
        udata.dxpl_id = io_info->dxpl_id;

        /* Call generic sequence operation routine */
        if((ret_value = H5VM_opvv(dset_max_nseq, dset_curr_seq, dset_len_arr, dset_off_arr,
                mem_max_nseq, mem_curr_seq, mem_len_arr, mem_off_arr,
                H5D__contig_writevv_sieve_cb, &udata)) < 0)
            HGOTO_ERROR(H5E_DATASET, H5E_CANTOPERATE, FAIL, "can't perform vectorized sieve buffer write")
    } /* end if */
    else {
        H5D_contig_writevv_ud_t udata;     /* User data for H5VM_opvv() operator */

        /* Set up user data for H5VM_opvv() */
        udata.file = io_info->dset->oloc.file;
        udata.dset_addr = io_info->store->contig.dset_addr;
        udata.wbuf = (const unsigned char *)io_info->u.wbuf;
        udata.dxpl_id = io_info->dxpl_id;

        /* Call generic sequence operation routine */
        if((ret_value = H5VM_opvv(dset_max_nseq, dset_curr_seq, dset_len_arr, dset_off_arr,
                mem_max_nseq, mem_curr_seq, mem_len_arr, mem_off_arr,
                H5D__contig_writevv_cb, &udata)) < 0)
            HGOTO_ERROR(H5E_DATASET, H5E_CANTOPERATE, FAIL, "can't perform vectorized read")
    } /* end else */

done:
    FUNC_LEAVE_NOAPI(ret_value)
}   /* end H5D__contig_writevv() */


/*-------------------------------------------------------------------------
 * Function:	H5D__contig_flush
 *
 * Purpose:	Writes all dirty data to disk.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Quincey Koziol
 *              Monday, July 27, 2009
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5D__contig_flush(H5D_t *dset, hid_t dxpl_id)
{
    herr_t ret_value = SUCCEED;       /* Return value */

    FUNC_ENTER_STATIC

    /* Sanity check */
    HDassert(dset);

    /* Flush any data in sieve buffer */
    if(H5D__flush_sieve_buf(dset, dxpl_id) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTFLUSH, FAIL, "unable to flush sieve buffer")

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D__contig_flush() */


/*-------------------------------------------------------------------------
 * Function:	H5D__contig_copy
 *
 * Purpose:	Copy contiguous storage raw data from SRC file to DST file.
 *
 * Return:	Non-negative on success, negative on failure.
 *
 * Programmer:  Quincey Koziol
 *	        Monday, November 21, 2005
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5D__contig_copy(H5F_t *f_src, const H5O_storage_contig_t *storage_src,
    H5F_t *f_dst, H5O_storage_contig_t *storage_dst, H5T_t *dt_src,
    H5O_copy_t *cpy_info, hid_t dxpl_id)
{
    haddr_t     addr_src;               /* File offset in source dataset */
    haddr_t     addr_dst;               /* File offset in destination dataset */
    H5T_path_t  *tpath_src_mem = NULL, *tpath_mem_dst = NULL;   /* Datatype conversion paths */
    H5T_t       *dt_dst = NULL;         /* Destination datatype */
    H5T_t       *dt_mem = NULL;         /* Memory datatype */
    hid_t       tid_src = -1;           /* Datatype ID for source datatype */
    hid_t       tid_dst = -1;           /* Datatype ID for destination datatype */
    hid_t       tid_mem = -1;           /* Datatype ID for memory datatype */
    size_t      src_dt_size = 0;        /* Source datatype size */
    size_t      mem_dt_size = 0;        /* Memory datatype size */
    size_t      dst_dt_size = 0;        /* Destination datatype size */
    size_t      max_dt_size;            /* Max. datatype size */
    size_t      nelmts = 0;             /* Number of elements in buffer */
    size_t      src_nbytes;             /* Number of bytes to read from source */
    size_t      mem_nbytes;             /* Number of bytes to convert in memory */
    size_t      dst_nbytes;             /* Number of bytes to write to destination */
    hsize_t     total_src_nbytes;       /* Total number of bytes to copy */
    size_t      buf_size;               /* Size of copy buffer */
    void       *buf = NULL;             /* Buffer for copying data */
    void       *bkg = NULL;             /* Temporary buffer for copying data */
    void       *reclaim_buf = NULL;     /* Buffer for reclaiming data */
    H5S_t      *buf_space = NULL;       /* Dataspace describing buffer */
    hid_t       buf_sid = -1;           /* ID for buffer dataspace */
    hsize_t     buf_dim[1] = {0};       /* Dimension for buffer */
    hbool_t     is_vlen = FALSE;        /* Flag to indicate that VL type conversion should occur */
    hbool_t     fix_ref = FALSE;        /* Flag to indicate that ref values should be fixed */
    H5D_shared_t    *shared_fo = cpy_info->shared_fo;  /* Pointer to the shared struct for dataset object */
    hbool_t     try_sieve = FALSE;          /* Try to get data from the sieve buffer */
    haddr_t     sieve_start = HADDR_UNDEF;  /* Start location of sieve buffer */
    haddr_t     sieve_end = HADDR_UNDEF;    /* End locations of sieve buffer */ 
    herr_t      ret_value = SUCCEED;    /* Return value */

    FUNC_ENTER_PACKAGE

    /* Check args */
    HDassert(f_src);
    HDassert(storage_src);
    HDassert(f_dst);
    HDassert(storage_dst);
    HDassert(dt_src);

    /* Allocate space for destination raw data */
    if(H5D__contig_alloc(f_dst, dxpl_id, storage_dst) < 0)
        HGOTO_ERROR(H5E_IO, H5E_CANTINIT, FAIL, "unable to allocate contiguous storage")

    /* Set up number of bytes to copy, and initial buffer size */
    /* (actually use the destination size, which has been fixed up, if necessary) */
    total_src_nbytes = storage_dst->size;
    H5_CHECK_OVERFLOW(total_src_nbytes, hsize_t, size_t);
    buf_size = MIN(H5D_TEMP_BUF_SIZE, (size_t)total_src_nbytes);

    /* Create datatype ID for src datatype.  We may or may not use this ID,
     * but this ensures that the src datatype will be freed.
     */
    if((tid_src = H5I_register(H5I_DATATYPE, dt_src, FALSE)) < 0)
        HGOTO_ERROR(H5E_DATATYPE, H5E_CANTREGISTER, FAIL, "unable to register source file datatype")

    /* If there's a VLEN source datatype, set up type conversion information */
    if(H5T_detect_class(dt_src, H5T_VLEN, FALSE) > 0) {
        /* create a memory copy of the variable-length datatype */
        if(NULL == (dt_mem = H5T_copy(dt_src, H5T_COPY_TRANSIENT)))
            HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "unable to copy")
        if((tid_mem = H5I_register(H5I_DATATYPE, dt_mem, FALSE)) < 0) {
            H5T_close(dt_mem);
            HGOTO_ERROR(H5E_DATASET, H5E_CANTREGISTER, FAIL, "unable to register memory datatype")
        } /* end if */

        /* create variable-length datatype at the destinaton file */
        if(NULL == (dt_dst = H5T_copy(dt_src, H5T_COPY_TRANSIENT)))
            HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to copy")
        if(H5T_set_loc(dt_dst, f_dst, H5T_LOC_DISK) < 0) {
            H5T_close(dt_dst);
            HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "cannot mark datatype on disk")
        } /* end if */
        if((tid_dst = H5I_register(H5I_DATATYPE, dt_dst, FALSE)) < 0) {
            H5T_close(dt_dst);
            HGOTO_ERROR(H5E_DATASET, H5E_CANTREGISTER, FAIL, "unable to register destination file datatype")
        } /* end if */

        /* Set up the conversion functions */
        if(NULL == (tpath_src_mem = H5T_path_find(dt_src, dt_mem, NULL, NULL, dxpl_id, FALSE)))
            HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to convert between src and mem datatypes")
        if(NULL == (tpath_mem_dst = H5T_path_find(dt_mem, dt_dst, NULL, NULL, dxpl_id, FALSE)))
            HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to convert between mem and dst datatypes")

        /* Determine largest datatype size */
        if(0 == (src_dt_size = H5T_get_size(dt_src)))
            HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to determine datatype size")
        if(0 == (mem_dt_size = H5T_get_size(dt_mem)))
            HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to determine datatype size")
        max_dt_size = MAX(src_dt_size, mem_dt_size);
        if(0 == (dst_dt_size = H5T_get_size(dt_dst)))
            HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to determine datatype size")
        max_dt_size = MAX(max_dt_size, dst_dt_size);

        /* Set maximum number of whole elements that fit in buffer */
        if(0 == (nelmts = buf_size / max_dt_size))
            HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "element size too large")

        /* Set the number of bytes to transfer */
        src_nbytes = nelmts * src_dt_size;
        dst_nbytes = nelmts * dst_dt_size;
        mem_nbytes = nelmts * mem_dt_size;

        /* Adjust buffer size to be multiple of elements */
        buf_size = nelmts * max_dt_size;

        /* Create dataspace for number of elements in buffer */
        buf_dim[0] = nelmts;

        /* Create the space and set the initial extent */
        if(NULL == (buf_space = H5S_create_simple((unsigned)1, buf_dim, NULL)))
            HGOTO_ERROR(H5E_DATASPACE, H5E_CANTCREATE, FAIL, "can't create simple dataspace")

        /* Atomize */
        if((buf_sid = H5I_register(H5I_DATASPACE, buf_space, FALSE)) < 0) {
            H5S_close(buf_space);
            HGOTO_ERROR(H5E_ATOM, H5E_CANTREGISTER, FAIL, "unable to register dataspace ID")
        } /* end if */

        /* Set flag to do type conversion */
        is_vlen = TRUE;
    } /* end if */
    else {
        /* Check for reference datatype */
        if(H5T_get_class(dt_src, FALSE) == H5T_REFERENCE) {
            /* Need to fix values of references when copying across files */
            if(f_src != f_dst)
                fix_ref = TRUE;
        } /* end if */

        /* Set the number of bytes to read & write to the buffer size */
        src_nbytes = dst_nbytes = mem_nbytes = buf_size;
    } /* end else */

    /* Allocate space for copy buffer */
    HDassert(buf_size);
    if(NULL == (buf = H5FL_BLK_MALLOC(type_conv, buf_size)))
        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed for copy buffer")

    /* Need extra buffer for datatype conversions, to prevent stranding/leaking memory */
    if(is_vlen || fix_ref) {
        if(NULL == (reclaim_buf = H5FL_BLK_MALLOC(type_conv, buf_size)))
            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed for copy buffer")

        /* allocate temporary bkg buff for data conversion */
        if(NULL == (bkg = H5FL_BLK_MALLOC(type_conv, buf_size)))
            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed for copy buffer")
    } /* end if */

    addr_src = storage_src->addr;
    addr_dst = storage_dst->addr;

    /* If data sieving is enabled and the dataset is open in the file,
       set up to copy data out of the sieve buffer if deemed possible later */
    if(H5F_HAS_FEATURE(f_src, H5FD_FEAT_DATA_SIEVE) &&
       shared_fo && shared_fo->cache.contig.sieve_buf) {
        try_sieve = TRUE;
        sieve_start = shared_fo->cache.contig.sieve_loc;
        sieve_end = sieve_start + shared_fo->cache.contig.sieve_size;
        /* 
         * It is possble for addr_src to be undefined when:
         *  (a) The dataset is created and data is written to it.
         *  (b) The dataset is then copied via H5Ocopy().
         *  H5D_mark() in H5Dint.c is different between 
         *  1.8 and develop branches:
         *  1.8--it just sets dataset->shared->layout_dirty as TRUE 
         *       to be flushed later.
         *  develop--it will flush the layout message if it has been changed.
         */
        if(!H5F_addr_defined(addr_src))
            addr_src = sieve_start;
    }

    HDassert(H5F_addr_defined(addr_src));
    /* Loop over copying data */
    while(total_src_nbytes > 0) {
        /* Check if we should reduce the number of bytes to transfer */
        if(total_src_nbytes < src_nbytes) {
            /* Adjust bytes to transfer */
            src_nbytes = (size_t)total_src_nbytes;

            /* Adjust dataspace describing buffer */
            if(is_vlen) {
                /* Adjust destination & memory bytes to transfer */
                nelmts = src_nbytes / src_dt_size;
                dst_nbytes = nelmts * dst_dt_size;
                mem_nbytes = nelmts * mem_dt_size;

                /* Adjust size of buffer's dataspace dimension */
                buf_dim[0] = nelmts;

                /* Adjust size of buffer's dataspace */
                if(H5S_set_extent_real(buf_space, buf_dim) < 0)
                    HGOTO_ERROR(H5E_DATASPACE, H5E_CANTSET, FAIL, "unable to change buffer dataspace size")
            } /* end if */
            else
                /* Adjust destination & memory bytes to transfer */
                dst_nbytes = mem_nbytes = src_nbytes;
        } /* end if */

         /* If the entire copy is within the sieve buffer, copy data from the sieve buffer */
        if(try_sieve && (addr_src >= sieve_start) && ((addr_src + src_nbytes -1) < sieve_end)) {
            unsigned char *base_sieve_buf = shared_fo->cache.contig.sieve_buf + (addr_src - sieve_start);

            HDmemcpy(buf, base_sieve_buf, src_nbytes);
        } else
            /* Read raw data from source file */
            if(H5F_block_read(f_src, H5FD_MEM_DRAW, addr_src, src_nbytes, H5P_DATASET_XFER_DEFAULT, buf) < 0)
                HGOTO_ERROR(H5E_DATASET, H5E_READERROR, FAIL, "unable to read raw data")

        /* Perform datatype conversion, if necessary */
        if(is_vlen) {
            /* Convert from source file to memory */
            if(H5T_convert(tpath_src_mem, tid_src, tid_mem, nelmts, (size_t)0, (size_t)0, buf, bkg, dxpl_id) < 0)
                HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "datatype conversion failed")

            /* Copy into another buffer, to reclaim memory later */
            HDmemcpy(reclaim_buf, buf, mem_nbytes);

            /* Set background buffer to all zeros */
            HDmemset(bkg, 0, buf_size);

            /* Convert from memory to destination file */
            if(H5T_convert(tpath_mem_dst, tid_mem, tid_dst, nelmts, (size_t)0, (size_t)0, buf, bkg, dxpl_id) < 0)
                HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "datatype conversion failed")

            /* Reclaim space from variable length data */
            if(H5D_vlen_reclaim(tid_mem, buf_space, H5P_DATASET_XFER_DEFAULT, reclaim_buf) < 0)
                HGOTO_ERROR(H5E_DATASET, H5E_BADITER, FAIL, "unable to reclaim variable-length data")
        } /* end if */
        else if(fix_ref) {
            /* Check for expanding references */
            if(cpy_info->expand_ref) {
                size_t ref_count;

                /* Determine # of reference elements to copy */
                ref_count = src_nbytes / H5T_get_size(dt_src);

                /* Copy the reference elements */
                if(H5O_copy_expand_ref(f_src, buf, dxpl_id, f_dst, bkg, ref_count, H5T_get_ref_type(dt_src), cpy_info) < 0)
                    HGOTO_ERROR(H5E_DATASET, H5E_CANTCOPY, FAIL, "unable to copy reference attribute")

                /* After fix ref, copy the new reference elements to the buffer to write out */
                HDmemcpy(buf, bkg,  buf_size);
            } /* end if */
            else
                /* Reset value to zero */
                HDmemset(buf, 0, src_nbytes);
        } /* end if */

        /* Write raw data to destination file */
        if(H5F_block_write(f_dst, H5FD_MEM_DRAW, addr_dst, dst_nbytes, H5P_DATASET_XFER_DEFAULT, buf) < 0)
            HGOTO_ERROR(H5E_DATASET, H5E_WRITEERROR, FAIL, "unable to write raw data")

        /* Adjust loop variables */
        addr_src += src_nbytes;
        addr_dst += dst_nbytes;
        total_src_nbytes -= src_nbytes;
    } /* end while */

done:
    if(buf_sid > 0 && H5I_dec_ref(buf_sid) < 0)
        HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "can't decrement temporary dataspace ID")
    if(tid_src > 0 && H5I_dec_ref(tid_src) < 0)
        HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "Can't decrement temporary datatype ID")
    if(tid_dst > 0 && H5I_dec_ref(tid_dst) < 0)
        HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "Can't decrement temporary datatype ID")
    if(tid_mem > 0 && H5I_dec_ref(tid_mem) < 0)
        HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, FAIL, "Can't decrement temporary datatype ID")
    if(buf)
        buf = H5FL_BLK_FREE(type_conv, buf);
    if(reclaim_buf)
        reclaim_buf = H5FL_BLK_FREE(type_conv, reclaim_buf);
    if(bkg)
        bkg = H5FL_BLK_FREE(type_conv, bkg);

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D__contig_copy() */