summaryrefslogtreecommitdiffstats
path: root/src/H5HFcache.c
blob: f5a03f533a50227eeec4f691990cd6a4aae7cbfc (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
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * 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://www.hdfgroup.org/licenses.               *
 * If you do not have access to either file, you may request a copy from     *
 * help@hdfgroup.org.                                                        *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/*-------------------------------------------------------------------------
 *
 * Created:		H5HFcache.c
 *			Feb 24 2006
 *			Quincey Koziol
 *
 * Purpose:		Implement fractal heap metadata cache methods.
 *
 *-------------------------------------------------------------------------
 */

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

#include "H5HFmodule.h" /* This source code file is part of the H5HF module */

/***********/
/* Headers */
/***********/
#include "H5private.h"   /* Generic Functions			*/
#include "H5ACprivate.h" /* Metadata cache			*/
#include "H5Eprivate.h"  /* Error handling		  	*/
#include "H5HFpkg.h"     /* Fractal heaps			*/
#include "H5MFprivate.h" /* File memory management		*/
#include "H5MMprivate.h" /* Memory management			*/
#include "H5VMprivate.h" /* Vectors and arrays 			*/
#include "H5WBprivate.h" /* Wrapped Buffers                      */

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

/* Fractal heap format version #'s */
#define H5HF_HDR_VERSION    0 /* Header */
#define H5HF_DBLOCK_VERSION 0 /* Direct block */
#define H5HF_IBLOCK_VERSION 0 /* Indirect block */

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

/********************/
/* Package Typedefs */
/********************/

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

/* Local encode/decode routines */
static herr_t H5HF__hdr_prefix_decode(H5HF_hdr_t *hdr, const uint8_t **image_ref);
static herr_t H5HF__dtable_encode(H5F_t *f, uint8_t **pp, const H5HF_dtable_t *dtable);
static herr_t H5HF__dtable_decode(H5F_t *f, const uint8_t **pp, H5HF_dtable_t *dtable);

/* Metadata cache (H5AC) callbacks */
static herr_t H5HF__cache_hdr_get_initial_load_size(void *udata, size_t *image_len);
static herr_t H5HF__cache_hdr_get_final_load_size(const void *image_ptr, size_t image_len, void *udata,
                                                  size_t *actual_len);
static htri_t H5HF__cache_hdr_verify_chksum(const void *image_ptr, size_t len, void *udata_ptr);
static void * H5HF__cache_hdr_deserialize(const void *image, size_t len, void *udata, hbool_t *dirty);
static herr_t H5HF__cache_hdr_image_len(const void *thing, size_t *image_len);
static herr_t H5HF__cache_hdr_pre_serialize(H5F_t *f, void *thing, haddr_t addr, size_t len,
                                            haddr_t *new_addr, size_t *new_len, unsigned *flags);
static herr_t H5HF__cache_hdr_serialize(const H5F_t *f, void *image, size_t len, void *thing);
static herr_t H5HF__cache_hdr_free_icr(void *thing);

static herr_t H5HF__cache_iblock_get_initial_load_size(void *udata, size_t *image_len);
static htri_t H5HF__cache_iblock_verify_chksum(const void *image_ptr, size_t len, void *udata_ptr);
static void * H5HF__cache_iblock_deserialize(const void *image, size_t len, void *udata, hbool_t *dirty);
static herr_t H5HF__cache_iblock_image_len(const void *thing, size_t *image_len);
static herr_t H5HF__cache_iblock_pre_serialize(H5F_t *f, void *thing, haddr_t addr, size_t len,
                                               haddr_t *new_addr, size_t *new_len, unsigned *flags);
static herr_t H5HF__cache_iblock_serialize(const H5F_t *f, void *image, size_t len, void *thing);
static herr_t H5HF__cache_iblock_notify(H5AC_notify_action_t action, void *thing);
static herr_t H5HF__cache_iblock_free_icr(void *thing);

static herr_t H5HF__cache_dblock_get_initial_load_size(void *udata, size_t *image_len);
static htri_t H5HF__cache_dblock_verify_chksum(const void *image_ptr, size_t len, void *udata_ptr);
static void * H5HF__cache_dblock_deserialize(const void *image, size_t len, void *udata, hbool_t *dirty);
static herr_t H5HF__cache_dblock_image_len(const void *thing, size_t *image_len);
static herr_t H5HF__cache_dblock_pre_serialize(H5F_t *f, void *thing, haddr_t addr, size_t len,
                                               haddr_t *new_addr, size_t *new_len, unsigned *flags);
static herr_t H5HF__cache_dblock_serialize(const H5F_t *f, void *image, size_t len, void *thing);
static herr_t H5HF__cache_dblock_notify(H5AC_notify_action_t action, void *thing);
static herr_t H5HF__cache_dblock_free_icr(void *thing);
static herr_t H5HF__cache_dblock_fsf_size(const void *_thing, hsize_t *fsf_size);

/* Debugging Function Prototypes */
#ifndef NDEBUG
static herr_t H5HF__cache_verify_hdr_descendants_clean(H5F_t *f, H5HF_hdr_t *hdr, hbool_t *fd_clean,
                                                       hbool_t *clean);
static herr_t H5HF__cache_verify_iblock_descendants_clean(H5F_t *f, haddr_t fd_parent_addr,
                                                          H5HF_indirect_t *iblock, unsigned *iblock_status,
                                                          hbool_t *fd_clean, hbool_t *clean);
static herr_t H5HF__cache_verify_iblocks_dblocks_clean(H5F_t *f, haddr_t fd_parent_addr,
                                                       H5HF_indirect_t *iblock, hbool_t *fd_clean,
                                                       hbool_t *clean, hbool_t *has_dblocks);
static herr_t H5HF__cache_verify_descendant_iblocks_clean(H5F_t *f, haddr_t fd_parent_addr,
                                                          H5HF_indirect_t *iblock, hbool_t *fd_clean,
                                                          hbool_t *clean, hbool_t *has_iblocks);
#endif /* NDEBUG */

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

/* H5HF header inherits cache-like properties from H5AC */
const H5AC_class_t H5AC_FHEAP_HDR[1] = {{
    H5AC_FHEAP_HDR_ID,                     /* Metadata client ID */
    "fractal heap header",                 /* Metadata client name (for debugging) */
    H5FD_MEM_FHEAP_HDR,                    /* File space memory type for client */
    H5AC__CLASS_SPECULATIVE_LOAD_FLAG,     /* Client class behavior flags */
    H5HF__cache_hdr_get_initial_load_size, /* 'get_initial_load_size' callback */
    H5HF__cache_hdr_get_final_load_size,   /* 'get_final_load_size' callback */
    H5HF__cache_hdr_verify_chksum,         /* 'verify_chksum' callback */
    H5HF__cache_hdr_deserialize,           /* 'deserialize' callback */
    H5HF__cache_hdr_image_len,             /* 'image_len' callback */
    H5HF__cache_hdr_pre_serialize,         /* 'pre_serialize' callback */
    H5HF__cache_hdr_serialize,             /* 'serialize' callback */
    NULL,                                  /* 'notify' callback */
    H5HF__cache_hdr_free_icr,              /* 'free_icr' callback */
    NULL,                                  /* 'fsf_size' callback */
}};

/* H5HF indirect block inherits cache-like properties from H5AC */
const H5AC_class_t H5AC_FHEAP_IBLOCK[1] = {{
    H5AC_FHEAP_IBLOCK_ID,                     /* Metadata client ID */
    "fractal heap indirect block",            /* Metadata client name (for debugging) */
    H5FD_MEM_FHEAP_IBLOCK,                    /* File space memory type for client */
    H5AC__CLASS_NO_FLAGS_SET,                 /* Client class behavior flags */
    H5HF__cache_iblock_get_initial_load_size, /* 'get_initial_load_size' callback */
    NULL,                                     /* 'get_final_load_size' callback */
    H5HF__cache_iblock_verify_chksum,         /* 'verify_chksum' callback */
    H5HF__cache_iblock_deserialize,           /* 'deserialize' callback */
    H5HF__cache_iblock_image_len,             /* 'image_len' callback */
    H5HF__cache_iblock_pre_serialize,         /* 'pre_serialize' callback */
    H5HF__cache_iblock_serialize,             /* 'serialize' callback */
    H5HF__cache_iblock_notify,                /* 'notify' callback */
    H5HF__cache_iblock_free_icr,              /* 'free_icr' callback */
    NULL,                                     /* 'fsf_size' callback */
}};

/* H5HF direct block inherits cache-like properties from H5AC */
const H5AC_class_t H5AC_FHEAP_DBLOCK[1] = {{
    H5AC_FHEAP_DBLOCK_ID,                     /* Metadata client ID */
    "fractal heap direct block",              /* Metadata client name (for debugging) */
    H5FD_MEM_FHEAP_DBLOCK,                    /* File space memory type for client */
    H5AC__CLASS_NO_FLAGS_SET,                 /* Client class behavior flags */
    H5HF__cache_dblock_get_initial_load_size, /* 'get_initial_load_size' callback */
    NULL,                                     /* 'get_final_load_size' callback */
    H5HF__cache_dblock_verify_chksum,         /* 'verify_chksum' callback */
    H5HF__cache_dblock_deserialize,           /* 'deserialize' callback */
    H5HF__cache_dblock_image_len,             /* 'image_len' callback */
    H5HF__cache_dblock_pre_serialize,         /* 'pre_serialize' callback */
    H5HF__cache_dblock_serialize,             /* 'serialize' callback */
    H5HF__cache_dblock_notify,                /* 'notify' callback */
    H5HF__cache_dblock_free_icr,              /* 'free_icr' callback */
    H5HF__cache_dblock_fsf_size,              /* 'fsf_size' callback */
}};

/*****************************/
/* Library Private Variables */
/*****************************/

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

/* Declare a free list to manage heap direct block data to/from disk */
H5FL_BLK_DEFINE(direct_block);

/*-------------------------------------------------------------------------
 * Function:	H5HF__hdr_prefix_decode()
 *
 * Purpose:	Decode a fractal heap header's prefix
 *
 * Return:	Success:	SUCCEED
 *		Failure:	FAIL
 *
 * Programmer:	Quincey Koziol
 *		December 15, 2016
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5HF__hdr_prefix_decode(H5HF_hdr_t *hdr, const uint8_t **image_ref)
{
    const uint8_t *image     = *image_ref; /* Pointer into into supplied image */
    herr_t         ret_value = SUCCEED;    /* Return value */

    FUNC_ENTER_PACKAGE

    /* Sanity checks */
    HDassert(hdr);
    HDassert(image);

    /* Magic number */
    if (HDmemcmp(image, H5HF_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC) != 0)
        HGOTO_ERROR(H5E_HEAP, H5E_BADVALUE, FAIL, "wrong fractal heap header signature")
    image += H5_SIZEOF_MAGIC;

    /* Version */
    if (*image++ != H5HF_HDR_VERSION)
        HGOTO_ERROR(H5E_HEAP, H5E_VERSION, FAIL, "wrong fractal heap header version")

    /* General heap information */
    UINT16DECODE(image, hdr->id_len);     /* Heap ID length */
    UINT16DECODE(image, hdr->filter_len); /* I/O filters' encoded length */

    /* Update the image buffer pointer */
    *image_ref = image;

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5HF__hdr_prefix_decode() */

/*-------------------------------------------------------------------------
 * Function:	H5HF__dtable_decode
 *
 * Purpose:	Decodes the metadata for a doubling table
 *
 * Return:	Success:	Pointer to a new fractal heap
 *
 *		Failure:	NULL
 *
 * Programmer:	Quincey Koziol
 *		Feb 27 2006
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5HF__dtable_decode(H5F_t *f, const uint8_t **pp, H5HF_dtable_t *dtable)
{
    FUNC_ENTER_PACKAGE_NOERR

    /* Check arguments */
    HDassert(f);
    HDassert(pp && *pp);
    HDassert(dtable);

    /* Table width */
    UINT16DECODE(*pp, dtable->cparam.width);

    /* Starting block size */
    H5F_DECODE_LENGTH(f, *pp, dtable->cparam.start_block_size);

    /* Maximum direct block size */
    H5F_DECODE_LENGTH(f, *pp, dtable->cparam.max_direct_size);

    /* Maximum heap size (as # of bits) */
    UINT16DECODE(*pp, dtable->cparam.max_index);

    /* Starting # of rows in root indirect block */
    UINT16DECODE(*pp, dtable->cparam.start_root_rows);

    /* Address of table */
    H5F_addr_decode(f, pp, &(dtable->table_addr));

    /* Current # of rows in root indirect block */
    UINT16DECODE(*pp, dtable->curr_root_rows);

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* end H5HF__dtable_decode() */

/*-------------------------------------------------------------------------
 * Function:	H5HF__dtable_encode
 *
 * Purpose:	Encodes the metadata for a doubling table
 *
 * Return:	Success:	Pointer to a new fractal heap
 *
 *		Failure:	NULL
 *
 * Programmer:	Quincey Koziol
 *		Feb 27 2006
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5HF__dtable_encode(H5F_t *f, uint8_t **pp, const H5HF_dtable_t *dtable)
{
    FUNC_ENTER_PACKAGE_NOERR

    /* Check arguments */
    HDassert(f);
    HDassert(pp && *pp);
    HDassert(dtable);

    /* Table width */
    UINT16ENCODE(*pp, dtable->cparam.width);

    /* Starting block size */
    H5F_ENCODE_LENGTH(f, *pp, dtable->cparam.start_block_size);

    /* Maximum direct block size */
    H5F_ENCODE_LENGTH(f, *pp, dtable->cparam.max_direct_size);

    /* Maximum heap size (as # of bits) */
    UINT16ENCODE(*pp, dtable->cparam.max_index);

    /* Starting # of rows in root indirect block */
    UINT16ENCODE(*pp, dtable->cparam.start_root_rows);

    /* Address of root direct/indirect block */
    H5F_addr_encode(f, pp, dtable->table_addr);

    /* Current # of rows in root indirect block */
    UINT16ENCODE(*pp, dtable->curr_root_rows);

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* end H5HF__dtable_encode() */

/*-------------------------------------------------------------------------
 * Function:	H5HF__cache_hdr_get_initial_load_size()
 *
 * Purpose:	Determine the size of the fractal heap header on disk,
 *		and set *image_len to this value.
 *
 *		Note also that the value returned by this function presumes that
 *		there is no I/O filtering data in the header.  If there is, the
 *		size reported will be too small, and H5C__load_entry()
 *		will have to make two tries to load the fractal heap header.
 *
 * Return:	Success:	SUCCEED
 *		Failure:	FAIL
 *
 * Programmer:	John Mainzer
 *		6/21/14
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5HF__cache_hdr_get_initial_load_size(void *_udata, size_t *image_len)
{
    H5HF_hdr_cache_ud_t *udata = (H5HF_hdr_cache_ud_t *)_udata; /* Pointer to user data */
    H5HF_hdr_t           dummy_hdr;                             /* Dummy header -- to compute size */

    FUNC_ENTER_PACKAGE_NOERR

    /* Sanity checks */
    HDassert(udata);
    HDassert(image_len);

    /* Set the internal parameters for the heap */
    dummy_hdr.f           = udata->f;
    dummy_hdr.sizeof_size = H5F_SIZEOF_SIZE(udata->f);
    dummy_hdr.sizeof_addr = H5F_SIZEOF_ADDR(udata->f);

    /* Compute the 'base' size of the fractal heap header on disk */
    *image_len = (size_t)H5HF_HEADER_SIZE(&dummy_hdr);

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* end H5HF__cache_hdr_get_initial_load_size() */

/*-------------------------------------------------------------------------
 * Function:	H5HF__cache_hdr_get_final_load_size()
 *
 * Purpose:	Determine the final size of the fractal heap header on disk,
 *		and set *actual_len to this value.
 *
 * Return:	Success:	SUCCEED
 *		Failure:	FAIL
 *
 * Programmer:	Quincey Koziol
 *		November 18, 2016
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5HF__cache_hdr_get_final_load_size(const void *_image, size_t H5_ATTR_NDEBUG_UNUSED image_len, void *_udata,
                                    size_t *actual_len)
{
    H5HF_hdr_t           hdr;                                       /* Temporary fractal heap header */
    const uint8_t *      image     = (const uint8_t *)_image;       /* Pointer into into supplied image */
    H5HF_hdr_cache_ud_t *udata     = (H5HF_hdr_cache_ud_t *)_udata; /* User data for callback */
    herr_t               ret_value = SUCCEED;                       /* Return value */

    FUNC_ENTER_PACKAGE

    /* Sanity checks */
    HDassert(image);
    HDassert(udata);
    HDassert(actual_len);
    HDassert(*actual_len == image_len);

    /* Deserialize the fractal heap header's prefix */
    if (H5HF__hdr_prefix_decode(&hdr, &image) < 0)
        HGOTO_ERROR(H5E_HEAP, H5E_CANTDECODE, FAIL, "can't decode fractal heap header prefix")

    /* Check for I/O filter info on this heap */
    if (hdr.filter_len > 0)
        /* Compute the extra heap header size */
        *actual_len += (size_t)(H5F_SIZEOF_SIZE(udata->f) /* Size of size for filtered root direct block */
                                + (unsigned)4      /* Size of filter mask for filtered root direct block */
                                + hdr.filter_len); /* Size of encoded I/O filter info */

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5HF__cache_hdr_get_final_load_size() */

/*-------------------------------------------------------------------------
 * Function:    H5HF__cache_hdr_verify_chksum
 *
 * Purpose:     Verify the computed checksum of the data structure is the
 *              same as the stored chksum.
 *
 * Return:      Success:        TRUE/FALSE
 *              Failure:        Negative
 *
 * Programmer:  Vailin Choi; Aug 2015
 *
 *-------------------------------------------------------------------------
 */
static htri_t
H5HF__cache_hdr_verify_chksum(const void *_image, size_t len, void H5_ATTR_UNUSED *_udata)
{
    const uint8_t *image = (const uint8_t *)_image; /* Pointer into raw data buffer */
    uint32_t       stored_chksum;                   /* Stored metadata checksum value */
    uint32_t       computed_chksum;                 /* Computed metadata checksum value */
    htri_t         ret_value = TRUE;                /* Return value */

    FUNC_ENTER_PACKAGE_NOERR

    /* Check arguments */
    HDassert(image);

    /* Get stored and computed checksums */
    H5F_get_checksums(image, len, &stored_chksum, &computed_chksum);

    if (stored_chksum != computed_chksum)
        ret_value = FALSE;

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5HF__cache_hdr_verify_chksum() */

/*-------------------------------------------------------------------------
 * Function:	H5HF__cache_hdr_deserialize
 *
 * Purpose:	Given a buffer containing an on disk image of a fractal heap
 *		header block, allocate an instance of H5HF_hdr_t, load the contents
 *		of the buffer into into the new instance of H5HF_hdr_t, and then
 *		return a pointer to the new instance.
 *
 * Return:	Success:	Pointer to in core representation
 *		Failure:	NULL
 *
 * Programmer:	John Mainzer
 *		6/21/14
 *
 *-------------------------------------------------------------------------
 */
static void *
H5HF__cache_hdr_deserialize(const void *_image, size_t len, void *_udata, hbool_t H5_ATTR_UNUSED *dirty)
{
    H5HF_hdr_t *         hdr   = NULL;                          /* Fractal heap info */
    H5HF_hdr_cache_ud_t *udata = (H5HF_hdr_cache_ud_t *)_udata; /* User data for callback */
    const uint8_t *      image = (const uint8_t *)_image;       /* Pointer into into supplied image */
    uint32_t             stored_chksum;                         /* Stored metadata checksum value */
    uint8_t              heap_flags;                            /* Status flags for heap */
    void *               ret_value = NULL;                      /* Return value */

    FUNC_ENTER_PACKAGE

    /* Sanity checks */
    HDassert(image);
    HDassert(len > 0);
    HDassert(udata);
    HDassert(dirty);

    /* Allocate space for the fractal heap data structure */
    if (NULL == (hdr = H5HF__hdr_alloc(udata->f)))
        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")

    /* Deserialize the fractal heap header's prefix */
    if (H5HF__hdr_prefix_decode(hdr, &image) < 0)
        HGOTO_ERROR(H5E_HEAP, H5E_CANTDECODE, NULL, "can't decode fractal heap header prefix")

    /* Heap status flags */
    /* (bit 0: "huge" object IDs have wrapped) */
    /* (bit 1: checksum direct blocks) */
    heap_flags            = *image++;
    hdr->huge_ids_wrapped = heap_flags & H5HF_HDR_FLAGS_HUGE_ID_WRAPPED;
    hdr->checksum_dblocks = heap_flags & H5HF_HDR_FLAGS_CHECKSUM_DBLOCKS;

    /* "Huge" object information */
    UINT32DECODE(image, hdr->max_man_size);                 /* Max. size of "managed" objects */
    H5F_DECODE_LENGTH(udata->f, image, hdr->huge_next_id);  /* Next ID to use for "huge" object */
    H5F_addr_decode(udata->f, &image, &hdr->huge_bt2_addr); /* Address of "huge" object tracker B-tree */

    /* "Managed" object free space information */
    H5F_DECODE_LENGTH(udata->f, image,
                      hdr->total_man_free);           /* Internal free space in managed direct blocks */
    H5F_addr_decode(udata->f, &image, &hdr->fs_addr); /* Address of free section header */

    /* Heap statistics */
    H5F_DECODE_LENGTH(udata->f, image, hdr->man_size);
    H5F_DECODE_LENGTH(udata->f, image, hdr->man_alloc_size);
    H5F_DECODE_LENGTH(udata->f, image, hdr->man_iter_off);
    H5F_DECODE_LENGTH(udata->f, image, hdr->man_nobjs);
    H5F_DECODE_LENGTH(udata->f, image, hdr->huge_size);
    H5F_DECODE_LENGTH(udata->f, image, hdr->huge_nobjs);
    H5F_DECODE_LENGTH(udata->f, image, hdr->tiny_size);
    H5F_DECODE_LENGTH(udata->f, image, hdr->tiny_nobjs);

    /* Managed objects' doubling-table info */
    if (H5HF__dtable_decode(hdr->f, &image, &(hdr->man_dtable)) < 0)
        HGOTO_ERROR(H5E_HEAP, H5E_CANTENCODE, NULL, "unable to encode managed obj. doubling table info")

    /* Set the fractal heap header's 'base' size */
    hdr->heap_size = (size_t)H5HF_HEADER_SIZE(hdr);

    /* Sanity check */
    /* (allow for checksum not decoded yet) */
    HDassert((size_t)(image - (const uint8_t *)_image) == (hdr->heap_size - H5HF_SIZEOF_CHKSUM));

    /* Check for I/O filter information to decode */
    if (hdr->filter_len > 0) {
        H5O_pline_t *pline; /* Pipeline information from the header on disk */

        /* Sanity check */
        HDassert(len > hdr->heap_size); /* A header with filter info is > than a standard header */

        /* Compute the heap header's size */
        hdr->heap_size += (size_t)(hdr->sizeof_size /* Size of size for filtered root direct block */
                                   + (unsigned)4    /* Size of filter mask for filtered root direct block */
                                   + hdr->filter_len); /* Size of encoded I/O filter info */

        /* Decode the size of a filtered root direct block */
        H5F_DECODE_LENGTH(udata->f, image, hdr->pline_root_direct_size);

        /* Decode the filter mask for a filtered root direct block */
        UINT32DECODE(image, hdr->pline_root_direct_filter_mask);

        /* Decode I/O filter information */
        if (NULL == (pline = (H5O_pline_t *)H5O_msg_decode(hdr->f, NULL, H5O_PLINE_ID, len, image)))
            HGOTO_ERROR(H5E_HEAP, H5E_CANTDECODE, NULL, "can't decode I/O pipeline filters")

        /* Advance past filter info to checksum */
        image += hdr->filter_len;

        /* Copy the information into the header's I/O pipeline structure */
        if (NULL == H5O_msg_copy(H5O_PLINE_ID, pline, &(hdr->pline)))
            HGOTO_ERROR(H5E_HEAP, H5E_CANTCOPY, NULL, "can't copy I/O filter pipeline")

        /* Release the space allocated for the I/O pipeline filters */
        H5O_msg_free(H5O_PLINE_ID, pline);
    } /* end if */

    /* Metadata checksum */
    UINT32DECODE(image, stored_chksum);

    /* Sanity check */
    HDassert((size_t)(image - (const uint8_t *)_image) == hdr->heap_size);

    /* Finish initialization of heap header */
    if (H5HF__hdr_finish_init(hdr) < 0)
        HGOTO_ERROR(H5E_RESOURCE, H5E_CANTINIT, NULL, "can't finish initializing shared fractal heap header")

    /* Set return value */
    ret_value = (void *)hdr;

done:
    if (!ret_value && hdr)
        if (H5HF__hdr_free(hdr) < 0)
            HDONE_ERROR(H5E_HEAP, H5E_CANTRELEASE, NULL, "unable to release fractal heap header")

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5HF__cache_hdr_deserialize() */

/*-------------------------------------------------------------------------
 * Function:	H5HF__cache_hdr_image_len
 *
 * Purpose:	Return the actual size of the fractal heap header on
 *		disk image.
 *
 *		If the header contains filter information, this size will be
 *		larger than the value returned by H5HF__cache_hdr_get_initial_load_size().
 *
 * Return:	Success:	SUCCEED
 *		Failure:	FAIL
 *
 * Programmer:	John Mainzer
 *		6/21/14
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5HF__cache_hdr_image_len(const void *_thing, size_t *image_len)
{
    const H5HF_hdr_t *hdr = (const H5HF_hdr_t *)_thing; /* Fractal heap info */

    FUNC_ENTER_PACKAGE_NOERR

    /* Sanity checks */
    HDassert(hdr);
    HDassert(hdr->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
    HDassert(hdr->cache_info.type == H5AC_FHEAP_HDR);
    HDassert(image_len);

    *image_len = hdr->heap_size;

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* end H5HF__cache_hdr_image_len() */

/*-------------------------------------------------------------------------
 * Function:	H5HF__cache_hdr_pre_serialize
 *
 * Purpose:	As best I can tell, fractal heap header blocks are always
 *		allocated in real file space.  Thus this routine simply verifies
 *		this, verifies that the len parameter contains the expected
 *		value, and returns an error if either of these checks fail.
 *
 *		When compiled in debug mode, the function also verifies that all
 *		indirect and direct blocks that are children of the header are
 *		either clean, or not in the metadata cache.
 *
 * Return:	Success:	SUCCEED
 *		Failure:	FAIL
 *
 * Programmer:	John Mainzer
 *		6/21/14
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5HF__cache_hdr_pre_serialize(H5F_t *f, void *_thing, haddr_t addr, size_t len,
                              haddr_t H5_ATTR_UNUSED *new_addr, size_t H5_ATTR_UNUSED *new_len,
                              unsigned *flags)
{
    H5HF_hdr_t *hdr       = (H5HF_hdr_t *)_thing; /* Fractal heap info */
    herr_t      ret_value = SUCCEED;              /* Return value */

    FUNC_ENTER_PACKAGE

    /* Sanity checks */
    HDassert(f);
    HDassert(hdr);
    HDassert(hdr->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
    HDassert(hdr->cache_info.type == H5AC_FHEAP_HDR);
    HDassert(H5F_addr_defined(addr));
    HDassert(addr == hdr->heap_addr);
    HDassert(new_addr);
    HDassert(new_len);
    HDassert(flags);

#ifndef NDEBUG
    {
        hbool_t descendants_clean = TRUE;
        hbool_t fd_children_clean = TRUE;

        /* Verify that flush dependencies are working correctly.  Do this
         * by verifying that either:
         *
         * 1) the header has a root iblock, and that the root iblock and all
         *    of its children are clean, or
         *
         * 2) The header has a root dblock, which is clean, or
         *
         * 3) The heap is empty, and thus the header has neither a root
         *    iblock no a root dblock.  In this case, the flush ordering
         *    constraint is met by default.
         *
         * Do this with a call to H5HF__cache_verify_hdr_descendants_clean().
         *
         * Note that descendants need not be clean if the pre_serialize call
         * is made during a cache serialization instead of an entry or cache
         * flush.
         *
         * Note also that with the recent change in the definition of flush
         * dependency, not all descendants need be clean -- only direct flush
         * dependency children.
         *
         * Finally, observe that the H5HF__cache_verify_hdr_descendants_clean()
         * call still looks for dirty descendants.  At present we do not check
         * this value.
         */
        if (H5HF__cache_verify_hdr_descendants_clean((H5F_t *)f, hdr, &fd_children_clean,
                                                     &descendants_clean) < 0)
            HGOTO_ERROR(H5E_HEAP, H5E_SYSTEM, FAIL, "can't verify hdr descendants clean.")
        HDassert(fd_children_clean);
    }
#endif /* NDEBUG */

    if (H5F_IS_TMP_ADDR(f, addr))
        HGOTO_ERROR(H5E_HEAP, H5E_BADVALUE, FAIL, "addr in temporary space?!?.");

    if (len != hdr->heap_size)
        HGOTO_ERROR(H5E_HEAP, H5E_BADVALUE, FAIL, "unexpected image len.");

    *flags = 0;

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5HF__cache_hdr_pre_serialize() */

/*-------------------------------------------------------------------------
 * Function:	H5HF__cache_hdr_serialize
 *
 * Purpose:	Construct the on disk image of the header, and place it in
 *		the buffer pointed to by image.  Return SUCCEED on success,
 *		and FAIL on failure.
 *
 * Return:	Success:	SUCCEED
 *		Failure:	FAIL
 *
 * Programmer:	John Mainzer
 *		6/21/14
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5HF__cache_hdr_serialize(const H5F_t *f, void *_image, size_t H5_ATTR_NDEBUG_UNUSED len, void *_thing)
{
    H5HF_hdr_t *hdr   = (H5HF_hdr_t *)_thing; /* Fractal heap info */
    uint8_t *   image = (uint8_t *)_image;    /* Pointer into raw data buffer */
    uint8_t     heap_flags;                   /* Status flags for heap */
    uint32_t    metadata_chksum;              /* Computed metadata checksum value */
    herr_t      ret_value = SUCCEED;          /* Return value */

    FUNC_ENTER_PACKAGE

    /* Sanity checks */
    HDassert(f);
    HDassert(image);
    HDassert(hdr);
    HDassert(hdr->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
    HDassert(hdr->cache_info.type == H5AC_FHEAP_HDR);
    HDassert(len == hdr->heap_size);

    /* Set the shared heap header's file context for this operation */
    H5_GCC_DIAG_OFF("discarded-qualifiers")
    H5_CLANG_DIAG_OFF("incompatible-pointer-types-discards-qualifiers")
    hdr->f = f;
    H5_GCC_DIAG_ON("discarded-qualifiers")
    H5_CLANG_DIAG_ON("incompatible-pointer-types-discards-qualifiers")

    /* Magic number */
    H5MM_memcpy(image, H5HF_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC);
    image += H5_SIZEOF_MAGIC;

    /* Version # */
    *image++ = H5HF_HDR_VERSION;

    /* General heap information */
    UINT16ENCODE(image, hdr->id_len);     /* Heap ID length */
    UINT16ENCODE(image, hdr->filter_len); /* I/O filters' encoded length */

    /* Heap status flags */
    /* (bit 0: "huge" object IDs have wrapped) */
    /* (bit 1: checksum direct blocks) */
    heap_flags = 0;
    heap_flags = (uint8_t)(heap_flags | (hdr->huge_ids_wrapped ? H5HF_HDR_FLAGS_HUGE_ID_WRAPPED : 0));
    heap_flags = (uint8_t)(heap_flags | (hdr->checksum_dblocks ? H5HF_HDR_FLAGS_CHECKSUM_DBLOCKS : 0));
    *image++   = heap_flags;

    /* "Huge" object information */
    UINT32ENCODE(image, hdr->max_man_size);         /* Max. size of "managed" objects */
    H5F_ENCODE_LENGTH(f, image, hdr->huge_next_id); /* Next ID to use for "huge" object */
    H5F_addr_encode(f, &image, hdr->huge_bt2_addr); /* Address of "huge" object tracker B-tree */

    /* "Managed" object free space information */
    H5F_ENCODE_LENGTH(f, image, hdr->total_man_free); /* Internal free space in managed direct blocks */
    H5F_addr_encode(f, &image, hdr->fs_addr);         /* Address of free section header */

    /* Heap statistics */
    H5F_ENCODE_LENGTH(f, image, hdr->man_size);
    H5F_ENCODE_LENGTH(f, image, hdr->man_alloc_size);
    H5F_ENCODE_LENGTH(f, image, hdr->man_iter_off);
    H5F_ENCODE_LENGTH(f, image, hdr->man_nobjs);
    H5F_ENCODE_LENGTH(f, image, hdr->huge_size);
    H5F_ENCODE_LENGTH(f, image, hdr->huge_nobjs);
    H5F_ENCODE_LENGTH(f, image, hdr->tiny_size);
    H5F_ENCODE_LENGTH(f, image, hdr->tiny_nobjs);

    /* Managed objects' doubling-table info */
    if (H5HF__dtable_encode(hdr->f, &image, &(hdr->man_dtable)) < 0)
        HGOTO_ERROR(H5E_HEAP, H5E_CANTENCODE, FAIL, "unable to encode managed obj. doubling table info")

    /* Check for I/O filter information to encode */
    if (hdr->filter_len > 0) {
        /* Encode the size of a filtered root direct block */
        H5F_ENCODE_LENGTH(f, image, hdr->pline_root_direct_size);

        /* Encode the filter mask for a filtered root direct block */
        UINT32ENCODE(image, hdr->pline_root_direct_filter_mask);

        /* Encode I/O filter information */
        if (H5O_msg_encode(hdr->f, H5O_PLINE_ID, FALSE, image, &(hdr->pline)) < 0)
            HGOTO_ERROR(H5E_HEAP, H5E_CANTENCODE, FAIL, "can't encode I/O pipeline filters")
        image += hdr->filter_len;
    } /* end if */

    /* Compute metadata checksum */
    metadata_chksum = H5_checksum_metadata(_image, (size_t)(image - (uint8_t *)_image), 0);

    /* Metadata checksum */
    UINT32ENCODE(image, metadata_chksum);

    /* sanity check */
    HDassert((size_t)(image - (uint8_t *)_image) == len);

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5HF__cache_hdr_serialize() */

/*-------------------------------------------------------------------------
 * Function:	H5HF__cache_hdr_free_icr
 *
 * Purpose:	Free the in core representation of the fractal heap header.
 *
 *		This routine frees just the header itself, not the
 *		associated version 2 B-Tree, the associated Free Space Manager,
 *		nor the indirect/direct block tree that is rooted in the header.
 *
 *		This routine also does not free the file space that may
 *		be allocated to the header.
 *
 * Note:	The metadata cache sets the object's cache_info.magic to
 *		H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC before calling a free_icr
 *		callback (checked in assert).
 *
 * Return:	Success:	SUCCEED
 *		Failure:	FAIL
 *
 * Programmer:	John Mainzer
 *		6/21/14
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5HF__cache_hdr_free_icr(void *_thing)
{
    H5HF_hdr_t *hdr       = (H5HF_hdr_t *)_thing; /* Fractal heap info */
    herr_t      ret_value = SUCCEED;              /* Return value */

    FUNC_ENTER_PACKAGE

    /* Sanity checks */
    HDassert(hdr);
    HDassert(hdr->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC);
    HDassert(hdr->cache_info.type == H5AC_FHEAP_HDR);
    HDassert(hdr->rc == 0);

    if (H5HF__hdr_free(hdr) < 0)
        HGOTO_ERROR(H5E_HEAP, H5E_CANTRELEASE, FAIL, "unable to release fractal heap header")

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5HF__cache_hdr_free_icr() */

/*-------------------------------------------------------------------------
 * Function:	H5HF__cache_iblock_get_initial_load_size()
 *
 * Purpose:	Compute the size of the on disk image of the indirect
 *		block, and place this value in *image_len.
 *
 * Return:	Success:	SUCCEED
 *		Failure:	FAIL
 *
 * Programmer:	John Mainzer
 *		6/21/14
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5HF__cache_iblock_get_initial_load_size(void *_udata, size_t *image_len)
{
    H5HF_iblock_cache_ud_t *udata = (H5HF_iblock_cache_ud_t *)_udata; /* User data for callback */

    FUNC_ENTER_PACKAGE_NOERR

    /* Sanity checks */
    HDassert(udata);
    HDassert(udata->par_info);
    HDassert(udata->par_info->hdr);
    HDassert(image_len);

    /* Set the image length size */
    *image_len = (size_t)H5HF_MAN_INDIRECT_SIZE(udata->par_info->hdr, *udata->nrows);

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* end H5HF__cache_iblock_get_initial_load_size() */

/*-------------------------------------------------------------------------
 * Function:    H5HF__cache_iblock_verify_chksum
 *
 * Purpose:     Verify the computed checksum of the data structure is the
 *              same as the stored checksum.
 *
 * Return:      Success:        TRUE/FALSE
 *              Failure:        Negative
 *
 * Programmer:  Vailin Choi; Aug 2015
 *
 *-------------------------------------------------------------------------
 */
static htri_t
H5HF__cache_iblock_verify_chksum(const void *_image, size_t len, void H5_ATTR_UNUSED *_udata)
{
    const uint8_t *image = (const uint8_t *)_image; /* Pointer into raw data buffer */
    uint32_t       stored_chksum;                   /* Stored metadata checksum value */
    uint32_t       computed_chksum;                 /* Computed metadata checksum value */
    htri_t         ret_value = TRUE;                /* Return value */

    FUNC_ENTER_PACKAGE_NOERR

    /* Check arguments */
    HDassert(image);

    /* Get stored and computed checksums */
    H5F_get_checksums(image, len, &stored_chksum, &computed_chksum);

    if (stored_chksum != computed_chksum)
        ret_value = FALSE;

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5HF__cache_iblock_verify_chksum() */

/*-------------------------------------------------------------------------
 * Function:	H5HF__cache_iblock_deserialize
 *
 * Purpose:	Given a buffer containing the on disk image of the indirect
 *		block, allocate an instance of H5HF_indirect_t, load the data
 *		in the buffer into this new instance, and return a pointer to
 *		it.
 *
 *		As best I can tell, the size of the indirect block image is fully
 *		know before the image is loaded, so this function should succeed
 *		unless the image is corrupt or memory allocation fails.
 *
 * Return:	Success:	Pointer to in core representation
 *		Failure:	NULL
 *
 * Programmer:	John Mainzer
 *		6/21/14
 *
 *-------------------------------------------------------------------------
 */
static void *
H5HF__cache_iblock_deserialize(const void *_image, size_t H5_ATTR_NDEBUG_UNUSED len, void *_udata,
                               hbool_t H5_ATTR_UNUSED *dirty)
{
    H5HF_hdr_t *            hdr;                                       /* Shared fractal heap information */
    H5HF_iblock_cache_ud_t *udata  = (H5HF_iblock_cache_ud_t *)_udata; /* User data for callback */
    H5HF_indirect_t *       iblock = NULL;                             /* Indirect block info */
    const uint8_t *         image  = (const uint8_t *)_image;          /* Pointer into raw data buffer */
    haddr_t                 heap_addr;        /* Address of heap header in the file */
    uint32_t                stored_chksum;    /* Stored metadata checksum value */
    unsigned                u;                /* Local index variable */
    void *                  ret_value = NULL; /* Return value */

    FUNC_ENTER_PACKAGE

    /* Sanity checks */
    HDassert(image);
    HDassert(udata);
    HDassert(dirty);
    hdr = udata->par_info->hdr;
    HDassert(hdr->f);

    /* Set the shared heap header's file context for this operation */
    hdr->f = udata->f;

    /* Allocate space for the fractal heap indirect block */
    if (NULL == (iblock = H5FL_CALLOC(H5HF_indirect_t)))
        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")

    /* Share common heap information */
    iblock->hdr = hdr;
    if (H5HF__hdr_incr(hdr) < 0)
        HGOTO_ERROR(H5E_HEAP, H5E_CANTINC, NULL, "can't increment reference count on shared heap header")

    /* Set block's internal information */
    iblock->rc        = 0;
    iblock->nrows     = *udata->nrows;
    iblock->nchildren = 0;

    /* Compute size of indirect block */
    iblock->size = H5HF_MAN_INDIRECT_SIZE(hdr, iblock->nrows);

    /* sanity check */
    HDassert(iblock->size == len);

    /* Magic number */
    if (HDmemcmp(image, H5HF_IBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC) != 0)
        HGOTO_ERROR(H5E_HEAP, H5E_BADVALUE, NULL, "wrong fractal heap indirect block signature")
    image += H5_SIZEOF_MAGIC;

    /* Version */
    if (*image++ != H5HF_IBLOCK_VERSION)
        HGOTO_ERROR(H5E_HEAP, H5E_VERSION, NULL, "wrong fractal heap direct block version")

    /* Address of heap that owns this block */
    H5F_addr_decode(udata->f, &image, &heap_addr);
    if (H5F_addr_ne(heap_addr, hdr->heap_addr))
        HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, NULL, "incorrect heap header address for direct block")

    /* Address of parent block */
    iblock->parent = udata->par_info->iblock;
    /* this copy of the parent pointer is needed by the notify callback so */
    /* that it can take down flush dependencies on eviction even if        */
    /* the parent pointer has been nulled out.             JRM -- 5/18/14  */
    if (udata->par_info->iblock)
        iblock->fd_parent = udata->par_info->iblock;
    else
        iblock->fd_parent = udata->par_info->hdr;
    iblock->par_entry = udata->par_info->entry;
    if (iblock->parent) {
        /* Share parent block */
        if (H5HF__iblock_incr(iblock->parent) < 0)
            HGOTO_ERROR(H5E_HEAP, H5E_CANTINC, NULL,
                        "can't increment reference count on shared indirect block")

        /* Set max. # of rows in this block */
        iblock->max_rows = iblock->nrows;
    } /* end if */
    else {
        /* Set max. # of rows in this block */
        iblock->max_rows = hdr->man_dtable.max_root_rows;
    } /* end else */

    /* Offset of heap within the heap's address space */
    UINT64DECODE_VAR(image, iblock->block_off, hdr->heap_off_size);

    /* Allocate & decode child block entry tables */
    HDassert(iblock->nrows > 0);
    if (NULL == (iblock->ents = H5FL_SEQ_MALLOC(H5HF_indirect_ent_t,
                                                (size_t)(iblock->nrows * hdr->man_dtable.cparam.width))))
        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed for direct entries")

    if (hdr->filter_len > 0) {
        unsigned dir_rows; /* Number of direct rows in this indirect block */

        /* Compute the number of direct rows for this indirect block */
        dir_rows = MIN(iblock->nrows, hdr->man_dtable.max_direct_rows);

        /* Allocate indirect block filtered entry array */
        if (NULL == (iblock->filt_ents = H5FL_SEQ_MALLOC(H5HF_indirect_filt_ent_t,
                                                         (size_t)(dir_rows * hdr->man_dtable.cparam.width))))
            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed for block entries")
    } /* end if */
    else
        iblock->filt_ents = NULL;

    for (u = 0; u < (iblock->nrows * hdr->man_dtable.cparam.width); u++) {
        /* Decode child block address */
        H5F_addr_decode(udata->f, &image, &(iblock->ents[u].addr));

        /* Check for heap with I/O filters */
        if (hdr->filter_len > 0) {
            /* Sanity check */
            HDassert(iblock->filt_ents);

            /* Decode extra information for direct blocks */
            if (u < (hdr->man_dtable.max_direct_rows * hdr->man_dtable.cparam.width)) {
                /* Size of filtered direct block */
                H5F_DECODE_LENGTH(udata->f, image, iblock->filt_ents[u].size);

                /* Sanity check */
                /* (either both the address & size are defined or both are
                 *  not defined)
                 */
                HDassert((H5F_addr_defined(iblock->ents[u].addr) && iblock->filt_ents[u].size) ||
                         (!H5F_addr_defined(iblock->ents[u].addr) && iblock->filt_ents[u].size == 0));

                /* I/O filter mask for filtered direct block */
                UINT32DECODE(image, iblock->filt_ents[u].filter_mask);
            } /* end if */
        }     /* end if */

        /* Count child blocks */
        if (H5F_addr_defined(iblock->ents[u].addr)) {
            iblock->nchildren++;
            iblock->max_child = u;
        } /* end if */
    }     /* end for */

    /* Sanity check */
    HDassert(iblock->nchildren); /* indirect blocks w/no children should have been deleted */

    /* checksum verification already done by verify_chksum cb */

    /* Metadata checksum */
    UINT32DECODE(image, stored_chksum);

    /* Sanity check */
    HDassert((size_t)(image - (const uint8_t *)_image) == iblock->size);

    /* Check if we have any indirect block children */
    if (iblock->nrows > hdr->man_dtable.max_direct_rows) {
        unsigned indir_rows; /* Number of indirect rows in this indirect block */

        /* Compute the number of indirect rows for this indirect block */
        indir_rows = iblock->nrows - hdr->man_dtable.max_direct_rows;

        /* Allocate & initialize child indirect block pointer array */
        if (NULL == (iblock->child_iblocks = H5FL_SEQ_CALLOC(
                         H5HF_indirect_ptr_t, (size_t)(indir_rows * hdr->man_dtable.cparam.width))))
            HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, NULL, "memory allocation failed for block entries")
    } /* end if */
    else
        iblock->child_iblocks = NULL;

    /* Set return value */
    ret_value = (void *)iblock;

done:
    if (!ret_value && iblock)
        if (H5HF__man_iblock_dest(iblock) < 0)
            HDONE_ERROR(H5E_HEAP, H5E_CANTFREE, NULL, "unable to destroy fractal heap indirect block")

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5HF__cache_iblock_deserialize() */

/*-------------------------------------------------------------------------
 * Function:	H5HF__cache_iblock_image_len
 *
 * Purpose:	Return the size of the on disk image of the iblock.
 *
 * Return:	Success:	SUCCEED
 *		Failure:	FAIL
 *
 * Programmer:	John Mainzer
 *		6/21/14
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5HF__cache_iblock_image_len(const void *_thing, size_t *image_len)
{
    const H5HF_indirect_t *iblock = (const H5HF_indirect_t *)_thing; /* Indirect block info */

    FUNC_ENTER_PACKAGE_NOERR

    /* Sanity checks */
    HDassert(iblock);
    HDassert(iblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
    HDassert(iblock->cache_info.type == H5AC_FHEAP_IBLOCK);
    HDassert(image_len);

    *image_len = iblock->size;

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* end H5HF__cache_iblock_image_len() */

/*-------------------------------------------------------------------------
 * Function:	H5HF__cache_iblock_pre_serialize
 *
 * Purpose:	The primary objective of this function is to determine if the
 *		indirect block is currently allocated in temporary file space,
 *		and if so, to move it to real file space before the entry is
 *		serialized.
 *
 *		In debug compiles, this function also verifies that all
 *		immediate flush dependency children of this indirect block
 *		are either clean or are not in cache.
 *
 * Return:	Success:	SUCCEED
 *		Failure:	FAIL
 *
 * Programmer:	John Mainzer
 *		6/21/14
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5HF__cache_iblock_pre_serialize(H5F_t *f, void *_thing, haddr_t addr, size_t H5_ATTR_UNUSED len,
                                 haddr_t *new_addr, size_t H5_ATTR_UNUSED *new_len, unsigned *flags)
{
    H5HF_hdr_t *     hdr;                                   /* Shared fractal heap information */
    H5HF_indirect_t *iblock    = (H5HF_indirect_t *)_thing; /* Indirect block info */
    herr_t           ret_value = SUCCEED;                   /* Return value */

    FUNC_ENTER_PACKAGE

    /* Sanity checks */
    HDassert(f);
    HDassert(iblock);
    HDassert(iblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
    HDassert(iblock->cache_info.type == H5AC_FHEAP_IBLOCK);
    HDassert(iblock->cache_info.size == iblock->size);
    HDassert(H5F_addr_defined(addr));
    HDassert(H5F_addr_eq(iblock->addr, addr));
    HDassert(new_addr);
    HDassert(new_len);
    HDassert(flags);
    hdr = iblock->hdr;
    HDassert(hdr);
    HDassert(hdr->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
    HDassert(hdr->cache_info.type == H5AC_FHEAP_HDR);

#ifndef NDEBUG
    {
        hbool_t  descendants_clean = TRUE;
        hbool_t  fd_children_clean = TRUE;
        unsigned iblock_status     = 0;

        /* verify that flush dependencies are working correctly.  Do this
         * by verifying that all immediate flush dependency children of this
         * iblock are clean.
         */
        if (H5AC_get_entry_status(f, iblock->addr, &iblock_status) < 0)
            HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL, "can't get iblock status")

        /* since the current iblock is the guest of honor in a flush, we know
         * that it is locked into the cache for the duration of the call.  Hence
         * there is no need to check to see if it is pinned or protected, or to
         * protect it if it is not.
         */
        if (H5HF__cache_verify_iblock_descendants_clean((H5F_t *)f, iblock->addr, iblock, &iblock_status,
                                                        &fd_children_clean, &descendants_clean) < 0)
            HGOTO_ERROR(H5E_HEAP, H5E_SYSTEM, FAIL, "can't verify descendants clean.")
        HDassert(fd_children_clean);
    }
#endif /* NDEBUG */

    /* Check to see if we must re-allocate the iblock from temporary to
     * normal (AKA real) file space.
     */
    if (H5F_IS_TMP_ADDR(f, addr)) {
        haddr_t iblock_addr;

        /* Allocate 'normal' space for the new indirect block on disk */
        if (HADDR_UNDEF ==
            (iblock_addr = H5MF_alloc((H5F_t *)f, H5FD_MEM_FHEAP_IBLOCK, (hsize_t)iblock->size)))
            HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL, "file allocation failed for fractal heap indirect block")

        /* Sanity check */
        HDassert(!H5F_addr_eq(iblock->addr, iblock_addr));

        /* Let the metadata cache know the block moved */
        if (H5AC_move_entry((H5F_t *)f, H5AC_FHEAP_IBLOCK, iblock->addr, iblock_addr) < 0)
            HGOTO_ERROR(H5E_HEAP, H5E_CANTMOVE, FAIL, "unable to move indirect block")

        /* Update the internal address for the block */
        iblock->addr = iblock_addr;

        /* Check for root indirect block */
        if (NULL == iblock->parent) {
            /* Update information about indirect block's location */
            hdr->man_dtable.table_addr = iblock_addr;

            /* Mark that heap header was modified */
            if (H5HF__hdr_dirty(hdr) < 0)
                HGOTO_ERROR(H5E_HEAP, H5E_CANTDIRTY, FAIL, "can't mark heap header as dirty")
        } /* end if */
        else {
            H5HF_indirect_t *par_iblock; /* Parent indirect block */
            unsigned         par_entry;  /* Entry in parent indirect block */

            /* Get parent information */
            par_iblock = iblock->parent;
            par_entry  = iblock->par_entry;

            /* Update information about indirect block's location */
            par_iblock->ents[par_entry].addr = iblock_addr;

            /* Mark that parent was modified */
            if (H5HF__iblock_dirty(par_iblock) < 0)
                HGOTO_ERROR(H5E_HEAP, H5E_CANTDIRTY, FAIL, "can't mark heap header as dirty")
        } /* end if */

        *new_addr = iblock_addr;
        *flags    = H5AC__SERIALIZE_MOVED_FLAG;
    } /* end if */
    else
        *flags = 0;

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5HF__cache_iblock_pre_serialize() */

/*-------------------------------------------------------------------------
 * Function:	H5HF__cache_iblock_serialize
 *
 * Purpose:	Given a pointer to an iblock, and a pointer to a buffer of
 *		the appropriate size, write the contents of the iblock to the
 *		buffer in format appropriate for writing to disk.
 *
 * Return:	Success:	SUCCEED
 *		Failure:	FAIL
 *
 * Programmer:	John Mainzer
 *		6/21/14
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5HF__cache_iblock_serialize(const H5F_t *f, void *_image, size_t H5_ATTR_NDEBUG_UNUSED len, void *_thing)
{
    H5HF_hdr_t *     hdr;                                /* Shared fractal heap information */
    H5HF_indirect_t *iblock = (H5HF_indirect_t *)_thing; /* Indirect block info */
    uint8_t *        image  = (uint8_t *)_image;         /* Pointer into raw data buffer */
#ifndef NDEBUG
    unsigned nchildren = 0;       /* Track # of children */
    size_t   max_child = 0;       /* Track max. child entry used */
#endif                            /* NDEBUG */
    uint32_t metadata_chksum;     /* Computed metadata checksum value */
    size_t   u;                   /* Local index variable */
    herr_t   ret_value = SUCCEED; /* Return value */

    FUNC_ENTER_PACKAGE_NOERR

    /* Sanity checks */
    HDassert(f);
    HDassert(image);
    HDassert(iblock);
    HDassert(iblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
    HDassert(iblock->cache_info.type == H5AC_FHEAP_IBLOCK);
    HDassert(iblock->cache_info.size == iblock->size);
    HDassert(len == iblock->size);

    /* Indirect block must be in 'normal' file space */
    HDassert(!H5F_IS_TMP_ADDR(f, iblock->addr));
    HDassert(H5F_addr_eq(iblock->addr, iblock->cache_info.addr));

    /* Get the pointer to the shared heap header */
    hdr = iblock->hdr;

    /* Set the shared heap header's file context for this operation */
    H5_GCC_DIAG_OFF("discarded-qualifiers")
    H5_CLANG_DIAG_OFF("incompatible-pointer-types-discards-qualifiers")
    hdr->f = f;
    H5_GCC_DIAG_ON("discarded-qualifiers")
    H5_CLANG_DIAG_ON("incompatible-pointer-types-discards-qualifiers")

    /* Magic number */
    H5MM_memcpy(image, H5HF_IBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC);
    image += H5_SIZEOF_MAGIC;

    /* Version # */
    *image++ = H5HF_IBLOCK_VERSION;

    /* Address of heap header for heap which owns this block */
    H5F_addr_encode(f, &image, hdr->heap_addr);

    /* Offset of block in heap */
    UINT64ENCODE_VAR(image, iblock->block_off, hdr->heap_off_size);

    /* Encode indirect block-specific fields */
    for (u = 0; u < (iblock->nrows * hdr->man_dtable.cparam.width); u++) {
        /* Encode child block address */
        H5F_addr_encode(f, &image, iblock->ents[u].addr);

        /* Check for heap with I/O filters */
        if (hdr->filter_len > 0) {
            /* Sanity check */
            HDassert(iblock->filt_ents);

            /* Encode extra information for direct blocks */
            if (u < (hdr->man_dtable.max_direct_rows * hdr->man_dtable.cparam.width)) {
                /* Sanity check */
                /* (either both the address & size are defined or both are
                 *  not defined)
                 */
                HDassert((H5F_addr_defined(iblock->ents[u].addr) && iblock->filt_ents[u].size) ||
                         (!H5F_addr_defined(iblock->ents[u].addr) && iblock->filt_ents[u].size == 0));

                /* Size of filtered direct block */
                H5F_ENCODE_LENGTH(f, image, iblock->filt_ents[u].size);

                /* I/O filter mask for filtered direct block */
                UINT32ENCODE(image, iblock->filt_ents[u].filter_mask);
            } /* end if */
        }     /* end if */

#ifndef NDEBUG
        /* Count child blocks */
        if (H5F_addr_defined(iblock->ents[u].addr)) {
            nchildren++;
            if (u > max_child)
                max_child = u;
        } /* end if */
#endif    /* NDEBUG */
    }     /* end for */

    /* Compute checksum */
    metadata_chksum = H5_checksum_metadata((uint8_t *)_image, (size_t)(image - (uint8_t *)_image), 0);

    /* Metadata checksum */
    UINT32ENCODE(image, metadata_chksum);

    /* Sanity checks */
    HDassert((size_t)(image - (uint8_t *)_image) == iblock->size);
#ifndef NDEBUG
    HDassert(nchildren == iblock->nchildren);
    HDassert(max_child == iblock->max_child);
#endif /* NDEBUG */

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5HF__cache_iblock_serialize() */

/*-------------------------------------------------------------------------
 * Function:	H5HF__cache_iblock_notify
 *
 * Purpose:	This function is used to create and destroy flush dependency
 *		relationships between iblocks and their parents as indirect blocks
 *		are loaded / inserted and evicted from the metadata cache.
 *
 *		In general, the parent will be another iblock, but it may be the
 *		header if the iblock in question is the root iblock.
 *
 * Return:	Success:	SUCCEED
 *		Failure:	FAIL
 *
 * Programmer:	John Mainzer
 *		6/21/14
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5HF__cache_iblock_notify(H5AC_notify_action_t action, void *_thing)
{
    H5HF_indirect_t *iblock    = (H5HF_indirect_t *)_thing; /* Indirect block info */
    herr_t           ret_value = SUCCEED;                   /* Return value */

    FUNC_ENTER_PACKAGE

    /* Sanity checks */
    HDassert(iblock);
    HDassert(iblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
    HDassert(iblock->cache_info.type == H5AC_FHEAP_IBLOCK);
    HDassert(iblock->hdr);

    /* further sanity checks */
    if (iblock->parent == NULL) {
        /* pointer from hdr to root iblock will not be set up unless */
        /* the fractal heap has already pinned the hdr.  Do what     */
        /* sanity checking we can.                                   */
        if ((iblock->block_off == 0) && (iblock->hdr->root_iblock_flags & H5HF_ROOT_IBLOCK_PINNED))
            HDassert(iblock->hdr->root_iblock == iblock);
    } /* end if */
    else {
        /* if this is a child iblock, verify that the pointers are */
        /* either uninitialized or set up correctly.               */
        H5HF_indirect_t H5_ATTR_NDEBUG_UNUSED *par_iblock = iblock->parent;
        unsigned H5_ATTR_NDEBUG_UNUSED         indir_idx; /* Index in parent's child iblock pointer array */

        /* Sanity check */
        HDassert(par_iblock->child_iblocks);
        HDassert(iblock->par_entry >=
                 (iblock->hdr->man_dtable.max_direct_rows * iblock->hdr->man_dtable.cparam.width));

        /* Compute index in parent's child iblock pointer array */
        indir_idx = iblock->par_entry -
                    (iblock->hdr->man_dtable.max_direct_rows * iblock->hdr->man_dtable.cparam.width);

        /* The pointer to iblock in the parent may not be set yet -- */
        /* verify that it is either NULL, or that it has been set to */
        /* iblock.                                                   */
        HDassert((NULL == par_iblock->child_iblocks[indir_idx]) ||
                 (par_iblock->child_iblocks[indir_idx] == iblock));
    } /* end else */

    switch (action) {
        case H5AC_NOTIFY_ACTION_AFTER_INSERT:
        case H5AC_NOTIFY_ACTION_AFTER_LOAD:
            /* Create flush dependency with parent, if there is one */
            if (iblock->fd_parent)
                if (H5AC_create_flush_dependency(iblock->fd_parent, iblock) < 0)
                    HGOTO_ERROR(H5E_HEAP, H5E_CANTDEPEND, FAIL, "unable to create flush dependency")
            break;

        case H5AC_NOTIFY_ACTION_AFTER_FLUSH:
        case H5AC_NOTIFY_ACTION_ENTRY_DIRTIED:
        case H5AC_NOTIFY_ACTION_ENTRY_CLEANED:
        case H5AC_NOTIFY_ACTION_CHILD_DIRTIED:
        case H5AC_NOTIFY_ACTION_CHILD_CLEANED:
        case H5AC_NOTIFY_ACTION_CHILD_UNSERIALIZED:
        case H5AC_NOTIFY_ACTION_CHILD_SERIALIZED:
            /* do nothing */
            break;

        case H5AC_NOTIFY_ACTION_BEFORE_EVICT:
            if (iblock->fd_parent) {
                /* Destroy flush dependency with parent */
                if (H5AC_destroy_flush_dependency(iblock->fd_parent, iblock) < 0)
                    HGOTO_ERROR(H5E_HEAP, H5E_CANTUNDEPEND, FAIL, "unable to destroy flush dependency")
                iblock->fd_parent = NULL;
            } /* end if */
            break;

        default:
            HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "unknown action from metadata cache")
            break;
    } /* end switch */

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5HF__cache_iblock_notify() */

/*-------------------------------------------------------------------------
 * Function:	H5HF__cache_iblock_free_icr
 *
 * Purpose:	Unlink the supplied instance of H5HF_indirect_t from the
 *		fractal heap and free its memory.
 *
 * Note:	The metadata cache sets the object's cache_info.magic to
 *		H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC before calling a free_icr
 *		callback (checked in assert).
 *
 * Return:	Success:	SUCCEED
 *		Failure:	FAIL
 *
 * Programmer:	John Mainzer
 *		6/21/14
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5HF__cache_iblock_free_icr(void *thing)
{
    H5HF_indirect_t *iblock    = (H5HF_indirect_t *)thing; /* Fractal heap indirect block to free */
    herr_t           ret_value = SUCCEED;                  /* Return value */

    FUNC_ENTER_PACKAGE

    /* Sanity checks */
    HDassert(iblock);
    HDassert(iblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC);
    HDassert(iblock->cache_info.type == H5AC_FHEAP_IBLOCK);
    HDassert(iblock->rc == 0);
    HDassert(iblock->hdr);

    /* Destroy fractal heap indirect block */
    if (H5HF__man_iblock_dest(iblock) < 0)
        HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to destroy fractal heap indirect block")

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5HF__cache_iblock_free_icr() */

/*-------------------------------------------------------------------------
 * Function:	H5HF__cache_dblock_get_initial_load_size()
 *
 * Purpose:	Determine the size of the direct block on disk image, and
 *		return it in *image_len.
 *
 * Return:	Success:	SUCCEED
 *		Failure:	FAIL
 *
 * Programmer:	John Mainzer
 *		6/21/14
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5HF__cache_dblock_get_initial_load_size(void *_udata, size_t *image_len)
{
    const H5HF_dblock_cache_ud_t *udata = (const H5HF_dblock_cache_ud_t *)_udata; /* User data for callback */
    const H5HF_parent_t *         par_info; /* Pointer to parent information */
    const H5HF_hdr_t *            hdr;      /* Shared fractal heap information */

    FUNC_ENTER_PACKAGE_NOERR

    /* Sanity checks */
    HDassert(udata);
    HDassert(image_len);

    /* Convenience variables */
    par_info = (const H5HF_parent_t *)(&(udata->par_info));
    HDassert(par_info);
    hdr = par_info->hdr;
    HDassert(hdr);

    /* Check for I/O filters on this heap */
    if (hdr->filter_len > 0) {
        /* Check for root direct block */
        if (par_info->iblock == NULL)
            /* filtered root direct block */
            *image_len = hdr->pline_root_direct_size;
        else
            /* filtered direct block */
            *image_len = par_info->iblock->filt_ents[par_info->entry].size;
    } /* end if */
    else
        *image_len = udata->dblock_size;

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* end H5HF__cache_dblock_get_initial_load_size() */

/*-------------------------------------------------------------------------
 * Function:    H5HF__cache_dblock_verify_chksum
 *
 * Purpose:     Verify the computed checksum of the data structure is the
 *              same as the stored chksum.
 *
 * Return:      Success:        TRUE/FALSE
 *              Failure:        Negative
 *
 * Programmer:  Vailin Choi; Aug 2015
 *
 *-------------------------------------------------------------------------
 */
static htri_t
H5HF__cache_dblock_verify_chksum(const void *_image, size_t len, void *_udata)
{
    const uint8_t *         image    = (const uint8_t *)_image;          /* Pointer into raw data buffer */
    H5HF_dblock_cache_ud_t *udata    = (H5HF_dblock_cache_ud_t *)_udata; /* User data for callback */
    void *                  read_buf = NULL;                             /* Pointer to buffer to read in */
    H5HF_hdr_t *            hdr;                                         /* Shared fractal heap information */
    H5HF_parent_t *         par_info;                                    /* Pointer to parent information */
    uint32_t                stored_chksum;                               /* Stored metadata checksum value */
    uint32_t                computed_chksum;  /* Computed metadata checksum value */
    size_t                  chk_size;         /* The size for validating checksum */
    uint8_t *               chk_p;            /* Pointer to the area for validating checksum */
    htri_t                  ret_value = TRUE; /* Return value */

    FUNC_ENTER_PACKAGE

    /* Sanity checks */
    HDassert(image);
    HDassert(udata);
    par_info = (H5HF_parent_t *)(&(udata->par_info));
    HDassert(par_info);
    hdr = par_info->hdr;
    HDassert(hdr);

    /* Get out if data block is not checksummed */
    if (!(hdr->checksum_dblocks))
        HGOTO_DONE(TRUE);

    if (hdr->filter_len > 0) {
        size_t   nbytes;      /* Number of bytes used in buffer, after applying reverse filters */
        unsigned filter_mask; /* Excluded filters for direct block */
        H5Z_cb_t filter_cb;   /* Filter callback structure */

        /* Initialize the filter callback struct */
        filter_cb.op_data = NULL;
        filter_cb.func    = NULL; /* no callback function when failed */

        /* Allocate buffer to perform I/O filtering on and copy image into
         * it.  Must do this as H5Z_pipeline() may re-size the buffer
         * provided to it.
         */
        if (NULL == (read_buf = H5MM_malloc(len)))
            HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL, "memory allocation failed for pipeline buffer")

        /* Set up parameters for filter pipeline */
        nbytes      = len;
        filter_mask = udata->filter_mask;
        H5MM_memcpy(read_buf, image, len);

        /* Push direct block data through I/O filter pipeline */
        if (H5Z_pipeline(&(hdr->pline), H5Z_FLAG_REVERSE, &filter_mask, H5Z_ENABLE_EDC, filter_cb, &nbytes,
                         &len, &read_buf) < 0)
            HGOTO_ERROR(H5E_HEAP, H5E_CANTFILTER, FAIL, "output pipeline failed")

        /* Update info about direct block */
        udata->decompressed = TRUE;
        len                 = nbytes;
    }
    else {
        /* If the data are unfiltered, we just point to the image, which we
         * never modify. Casting away const is okay here.
         */
        H5_GCC_CLANG_DIAG_OFF("cast-qual")
        read_buf = (void *)image;
        H5_GCC_CLANG_DIAG_OFF("cast-qual")
    }

    /* Decode checksum */
    chk_size = (size_t)(H5HF_MAN_ABS_DIRECT_OVERHEAD(hdr) - H5HF_SIZEOF_CHKSUM);
    chk_p    = (uint8_t *)read_buf + chk_size;

    /* Metadata checksum */
    UINT32DECODE(chk_p, stored_chksum);

    chk_p -= H5HF_SIZEOF_CHKSUM;

    /* Reset checksum field, for computing the checksum */
    HDmemset(chk_p, 0, (size_t)H5HF_SIZEOF_CHKSUM);

    /* Compute checksum on entire direct block */
    computed_chksum = H5_checksum_metadata(read_buf, len, 0);

    /* Restore the checksum */
    UINT32ENCODE(chk_p, stored_chksum)

    /* Verify checksum */
    if (stored_chksum != computed_chksum)
        HGOTO_DONE(FALSE);

    /* Save the decompressed data to be used later in deserialize callback */
    if (hdr->filter_len > 0) {
        /* Sanity check */
        HDassert(udata->decompressed);
        HDassert(len == udata->dblock_size);

        /* Allocate block buffer */
        if (NULL == (udata->dblk = H5FL_BLK_MALLOC(direct_block, (size_t)len)))
            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed")

        /* Copy un-filtered data into block's buffer */
        H5MM_memcpy(udata->dblk, read_buf, len);
    } /* end if */

done:
    /* Release the read buffer */
    if (read_buf && read_buf != image)
        H5MM_xfree(read_buf);

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5HF__cache_dblock_verify_chksum() */

/*-------------------------------------------------------------------------
 * Function:	H5HF__cache_dblock_deserialize
 *
 * Purpose:	Given a buffer containing the on disk image of a direct
 *		block, allocate an instance of H5HF_direct_t, load the data
 *		in the buffer into this new instance, and return a pointer to
 *		it.
 *
 *		As best I can tell, the size of the direct block image is fully
 *		know before the image is loaded, so this function should succeed
 *		unless the image is corrupt or memory allocation fails.
 *
 * Return:	Success:	Pointer to in core representation
 *		Failure:	NULL
 *
 * Programmer:	John Mainzer
 *		6/21/14
 *
 *-------------------------------------------------------------------------
 */
static void *
H5HF__cache_dblock_deserialize(const void *_image, size_t len, void *_udata, hbool_t H5_ATTR_UNUSED *dirty)
{
    H5HF_hdr_t *            hdr;                                      /* Shared fractal heap information */
    H5HF_dblock_cache_ud_t *udata = (H5HF_dblock_cache_ud_t *)_udata; /* User data for callback */
    H5HF_parent_t *         par_info;                                 /* Pointer to parent information */
    H5HF_direct_t *         dblock   = NULL;                          /* Direct block info */
    const uint8_t *         image    = (const uint8_t *)_image;       /* Pointer into raw data buffer */
    void *                  read_buf = NULL;                          /* Pointer to buffer to decompress */
    haddr_t                 heap_addr;                                /* Address of heap header in the file */
    void *                  ret_value = NULL;                         /* Return value */

    FUNC_ENTER_PACKAGE

    /* Sanity checks */
    HDassert(image);
    HDassert(udata);
    par_info = (H5HF_parent_t *)(&(udata->par_info));
    HDassert(par_info);
    hdr = par_info->hdr;
    HDassert(hdr);
    HDassert(hdr->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
    HDassert(hdr->cache_info.type == H5AC_FHEAP_HDR);
    HDassert(dirty);

    /* Allocate space for the fractal heap direct block */
    if (NULL == (dblock = H5FL_CALLOC(H5HF_direct_t)))
        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
    HDmemset(&dblock->cache_info, 0, sizeof(H5AC_info_t));

    /* Set the shared heap header's file context for this operation */
    hdr->f = udata->f;

    /* Share common heap information */
    dblock->hdr = hdr;
    if (H5HF__hdr_incr(hdr) < 0)
        HGOTO_ERROR(H5E_HEAP, H5E_CANTINC, NULL, "can't increment reference count on shared heap header")

    /* Set block's internal information */
    dblock->size = udata->dblock_size;

    /* Check for I/O filters on this heap */
    if (hdr->filter_len > 0) {
        /* Direct block is already decompressed in verify_chksum callback */
        if (udata->decompressed) {
            /* Sanity check */
            HDassert(udata->dblk);

            /* Take ownership of the decompressed direct block */
            dblock->blk = udata->dblk;
            udata->dblk = NULL;
        } /* end if */
        else {
            H5Z_cb_t filter_cb;   /* Filter callback structure */
            size_t   nbytes;      /* Number of bytes used in buffer, after applying reverse filters */
            unsigned filter_mask; /* Excluded filters for direct block */

            /* Sanity check */
            HDassert(udata->dblk == NULL);

            /* Initialize the filter callback struct */
            filter_cb.op_data = NULL;
            filter_cb.func    = NULL; /* no callback function when failed */

            /* Allocate buffer to perform I/O filtering on and copy image into
             * it.  Must do this as H5Z_pipeline() may resize the buffer
             * provided to it.
             */
            if (NULL == (read_buf = H5MM_malloc(len)))
                HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, NULL, "memory allocation failed for pipeline buffer")

            /* Copy compressed image into buffer */
            H5MM_memcpy(read_buf, image, len);

            /* Push direct block data through I/O filter pipeline */
            nbytes      = len;
            filter_mask = udata->filter_mask;
            if (H5Z_pipeline(&(hdr->pline), H5Z_FLAG_REVERSE, &filter_mask, H5Z_ENABLE_EDC, filter_cb,
                             &nbytes, &len, &read_buf) < 0)
                HGOTO_ERROR(H5E_HEAP, H5E_CANTFILTER, NULL, "output pipeline failed")

            /* Sanity check */
            HDassert(nbytes == dblock->size);

            /* Copy un-filtered data into block's buffer */
            H5MM_memcpy(dblock->blk, read_buf, dblock->size);
        } /* end if */
    }     /* end if */
    else {
        /* Sanity checks */
        HDassert(udata->dblk == NULL);
        HDassert(!udata->decompressed);

        /* Allocate block buffer */
        /* XXX: Change to using free-list factories */
        if (NULL == (dblock->blk = H5FL_BLK_MALLOC(direct_block, (size_t)dblock->size)))
            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")

        /* Copy image to dblock->blk */
        HDassert(dblock->size == len);
        H5MM_memcpy(dblock->blk, image, dblock->size);
    } /* end else */

    /* Start decoding direct block */
    image = dblock->blk;

    /* Magic number */
    if (HDmemcmp(image, H5HF_DBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC) != 0)
        HGOTO_ERROR(H5E_HEAP, H5E_BADVALUE, NULL, "wrong fractal heap direct block signature")
    image += H5_SIZEOF_MAGIC;

    /* Version */
    if (*image++ != H5HF_DBLOCK_VERSION)
        HGOTO_ERROR(H5E_HEAP, H5E_VERSION, NULL, "wrong fractal heap direct block version")

    /* Address of heap that owns this block (just for file integrity checks) */
    H5F_addr_decode(udata->f, &image, &heap_addr);
    if (H5F_addr_ne(heap_addr, hdr->heap_addr))
        HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, NULL, "incorrect heap header address for direct block")

    /* Address of parent block */
    dblock->parent = par_info->iblock;
    if (par_info->iblock)
        dblock->fd_parent = par_info->iblock;
    else
        dblock->fd_parent = par_info->hdr;
    dblock->par_entry = par_info->entry;
    if (dblock->parent) {
        /* Share parent block */
        if (H5HF__iblock_incr(dblock->parent) < 0)
            HGOTO_ERROR(H5E_HEAP, H5E_CANTINC, NULL,
                        "can't increment reference count on shared indirect block")
    } /* end if */

    /* Offset of heap within the heap's address space */
    UINT64DECODE_VAR(image, dblock->block_off, hdr->heap_off_size);

    /* Decode checksum on direct block, if requested */
    if (hdr->checksum_dblocks) {
        uint32_t stored_chksum; /* Metadata checksum value */

        /* checksum verification already done in verify_chksum cb */

        /* Metadata checksum */
        UINT32DECODE(image, stored_chksum);
    } /* end if */

    /* Sanity check */
    HDassert((size_t)(image - dblock->blk) == (size_t)H5HF_MAN_ABS_DIRECT_OVERHEAD(hdr));

    /* Set return value */
    ret_value = (void *)dblock;

done:
    /* Release the read buffer */
    if (read_buf)
        H5MM_xfree(read_buf);

    /* Cleanup on error */
    if (!ret_value && dblock)
        if (H5HF__man_dblock_dest(dblock) < 0)
            HDONE_ERROR(H5E_HEAP, H5E_CANTFREE, NULL, "unable to destroy fractal heap direct block")

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5HF__cache_dblock_deserialize() */

/*-------------------------------------------------------------------------
 * Function:	H5HF__cache_dblock_image_len
 *
 * Purpose:	Report the actual size of the direct block image on disk.
 *		Note that this value will probably be incorrect if compression
 *		is enabled and the entry is dirty.
 *
 * Return:	Success:	SUCCEED
 *		Failure:	FAIL
 *
 * Programmer:	John Mainzer
 *		6/21/14
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5HF__cache_dblock_image_len(const void *_thing, size_t *image_len)
{
    const H5HF_direct_t *dblock = (const H5HF_direct_t *)_thing; /* Direct block info */
    const H5HF_hdr_t *   hdr;                                    /* Shared fractal heap information */
    size_t               size;

    FUNC_ENTER_PACKAGE_NOERR

    /* Sanity checks */
    HDassert(dblock);
    HDassert(dblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
    HDassert(dblock->cache_info.type == H5AC_FHEAP_DBLOCK);
    HDassert(image_len);

    /* Set up convenience variables */
    hdr = dblock->hdr;
    HDassert(hdr);

    /* Check for I/O filters on this heap */
    if (hdr->filter_len > 0) {
        /*
         * If the data is available, set to the compressed
         * size of the direct block -- otherwise set it equal to the
         * uncompressed size.
         *
         * We have three possible scenarios here.
         *
         * First, the block may never have been flushed.  In this
         * case, both dblock->file_size and the size stored in the
         * parent (either the header or the parent iblock) will all
         * be zero.  In this case, return the uncompressed size
         * stored in dblock->size as the size.
         *
         * Second, the block may have just been serialized, in which
         * case, dblock->file_size should be zero, and the correct
         * on disk size should be stored in the parent (again, either
         * the header or the parent iblock as case may be).
         *
         * Third, we may be in the process of discarding this
         * dblock without writing it.  In this case, dblock->file_size
         * should be non-zero and have the correct size.  Note that
         * in this case, the direct block will have been detached,
         * and thus looking up the parent will likely return incorrect
         * data.
         */
        if (dblock->file_size != 0)
            size = dblock->file_size;
        else {
            const H5HF_indirect_t *par_iblock = dblock->parent; /* Parent iblock */

            if (par_iblock)
                size = par_iblock->filt_ents[dblock->par_entry].size;
            else
                size = hdr->pline_root_direct_size;

            if (size == 0)
                size = dblock->size;
        } /* end else */
    }     /* end if */
    else
        size = dblock->size;

    /* Set the image size */
    HDassert(size > 0);
    *image_len = size;

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* end H5HF__cache_dblock_image_len() */

/*-------------------------------------------------------------------------
 * Function:	H5HF__cache_dblock_pre_serialize
 *
 * Purpose:	In principle, the purpose of this function is to determine
 *		the size and location of the disk image of the target direct
 *		block.  In this case, the uncompressed size of the block is
 *		fixed, but since the direct block could be compressed,
 *		we may need to compute and report the compressed size.
 *
 *		This is a bit sticky in the case of a direct block when I/O
 *		filters are enabled, as the size of the compressed version
 *		of the on disk image is not known until the direct block has
 *		been run through the filters.  Further, the location of the
 *		on disk image may change if the compressed size of the image
 *		changes as well.
 *
 *		To complicate matters further, the direct block may have been
 *		initially allocated in temporary (AKA imaginary) file space.
 *		In this case, we must relocate the direct block's on-disk
 *		image to "real" file space regardless of whether it has changed
 *		size.
 *
 *		One simplifying factor is the direct block's "blk" field,
 *		which contains a pointer to a buffer which (with the exception
 *		of a small header) contains the on disk image in uncompressed
 *		form.
 *
 *		To square this particular circle, this function does
 *		everything the serialize function usually does, with the
 *		exception of copying the image into the image buffer provided
 *		to the serialize function by the metadata cache.  The data to
 *		copy is provided to the serialize function in a buffer pointed
 *		to by the write_buf field.
 *
 *		If I/O filters are enabled, on exit,
 *		H5HF__cache_dblock_pre_serialize() sets the write_buf field to
 *		point to a buffer containing the filtered image of the direct
 *		block.  The serialize function should free this block, and set
 *		the write_buf field to NULL after copying it into the image
 *		buffer provided by the metadata cache.
 *
 *		If I/O filters are not enabled, this function prepares
 *		the buffer pointed to by the blk field for copying to the
 *		image buffer provided by the metadata cache, and sets the
 *		write_buf field equal to the blk field.  In this case, the
 *		serialize function should simply set the write_buf field to
 *		NULL after copying the direct block image into the image
 *		buffer.
 *
 *		In both of the above cases, the length of the buffer pointed
 *		to by write_buf is provided in the write_len field.  This
 *		field must contain 0 on entry to this function, and should
 *		be set back to 0 at the end of the serialize function.
 *
 * Return:	Success:	SUCCEED
 *		Failure:	FAIL
 *
 * Programmer:	John Mainzer
 *		6/21/14
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5HF__cache_dblock_pre_serialize(H5F_t *f, void *_thing, haddr_t addr, size_t len, haddr_t *new_addr,
                                 size_t *new_len, unsigned *flags)
{
    hbool_t at_tmp_addr; /* Flag to indicate direct block is */
                         /* at temporary address */
    haddr_t          dblock_addr;
    H5HF_hdr_t *     hdr;                              /* Shared fractal heap information */
    H5HF_direct_t *  dblock = (H5HF_direct_t *)_thing; /* Direct block info */
    H5HF_indirect_t *par_iblock;                       /* Parent indirect block */
    unsigned         par_entry = 0;                    /* Entry in parent indirect block */
    void *           write_buf;                        /* Pointer to buffer to write out */
    size_t           write_size;                       /* Size of buffer to write out */
    uint8_t *        image;                            /* Pointer into raw data buffer */
    unsigned         dblock_flags = 0;
    herr_t           ret_value    = SUCCEED; /* Return value */

    FUNC_ENTER_PACKAGE

    /* Sanity checks */
    HDassert(f);
    HDassert(dblock);
    HDassert(dblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
    HDassert(dblock->cache_info.type == H5AC_FHEAP_DBLOCK);
    HDassert(dblock->write_buf == NULL);
    HDassert(dblock->write_size == 0);
    HDassert(dblock->cache_info.size == len);
    HDassert(H5F_addr_defined(addr));
    HDassert(new_addr);
    HDassert(new_len);
    HDassert(flags);

    /* Set up local variables */
    hdr         = dblock->hdr;
    dblock_addr = addr; /* will update dblock_addr if we move the block */

    /* Set the shared heap header's file context for this operation */
    hdr->f = (H5F_t *)f;

    HDassert(hdr);
    HDassert(hdr->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
    HDassert(hdr->cache_info.type == H5AC_FHEAP_HDR);

    if (dblock->parent) {
        /* this is the common case, in which the direct block is the child
         * of an indirect block.  Set up the convenience variables we will
         * need if the address and/or compressed size of the on disk image
         * of the direct block changes, and do some sanity checking in
         * passing.
         */
        par_iblock = dblock->parent;
        par_entry  = dblock->par_entry;

        HDassert(par_iblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
        HDassert(par_iblock->cache_info.type == H5AC_FHEAP_IBLOCK);
        HDassert(H5F_addr_eq(par_iblock->ents[par_entry].addr, addr));
    } /* end if */
    else {
        /* the direct block is a root direct block -- just set par_iblock
         * to NULL, as the field will not be used.
         */
        par_iblock = NULL;
    } /* end else */

    at_tmp_addr = H5F_IS_TMP_ADDR(f, addr);

    /* Begin by preping the direct block to be written to disk.  Do
     * this by writing the correct magic number, the dblock version,
     * the address of the header, the offset of the block in the heap,
     * and the checksum at the beginning of the block.
     */

    HDassert(dblock->blk);
    image = dblock->blk;

    /* Magic number */
    H5MM_memcpy(image, H5HF_DBLOCK_MAGIC, (size_t)H5_SIZEOF_MAGIC);
    image += H5_SIZEOF_MAGIC;

    /* Version # */
    *image++ = H5HF_DBLOCK_VERSION;

    /* Address of heap header for heap which owns this block */
    H5F_addr_encode(f, &image, hdr->heap_addr);

    /* Offset of block in heap */
    UINT64ENCODE_VAR(image, dblock->block_off, hdr->heap_off_size);

    /* Metadata checksum */
    if (hdr->checksum_dblocks) {
        uint32_t metadata_chksum; /* Computed metadata checksum value */

        /* Clear the checksum field, to compute the checksum */
        HDmemset(image, 0, (size_t)H5HF_SIZEOF_CHKSUM);

        /* Compute checksum on entire direct block */
        metadata_chksum = H5_checksum_metadata(dblock->blk, dblock->size, 0);

        /* Metadata checksum */
        UINT32ENCODE(image, metadata_chksum);
    } /* end if */

    /* at this point, dblock->blk should point to an uncompressed image of
     * the direct block.  If I/O filters are not enabled, this image should
     * be ready to hand off to the metadata cache.
     */

    /* Sanity check */
    HDassert((size_t)(image - dblock->blk) == (size_t)H5HF_MAN_ABS_DIRECT_OVERHEAD(hdr));

    /* If I/O filters are enabled on this heap, we must run the direct block
     * image through the filters to obtain the image that we will hand off
     * to the metadata cache.
     */

    /* Check for I/O filters on this heap */
    if (hdr->filter_len > 0) {
        H5Z_cb_t filter_cb;       /* Filter callback structure */
        size_t   nbytes;          /* Number of bytes used */
        unsigned filter_mask = 0; /* Filter mask for block */

        /* Initialize the filter callback struct */
        filter_cb.op_data = NULL;
        filter_cb.func    = NULL; /* no callback function when failed */

        /* Allocate buffer to perform I/O filtering on */
        write_size = dblock->size;
        if (NULL == (write_buf = H5MM_malloc(write_size)))
            HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL, "memory allocation failed for pipeline buffer")

        /* Copy the direct block's image into the buffer to compress */
        H5MM_memcpy(write_buf, dblock->blk, write_size);

        /* Push direct block data through I/O filter pipeline */
        nbytes = write_size;
        if (H5Z_pipeline(&(hdr->pline), 0, &filter_mask, H5Z_ENABLE_EDC, filter_cb, &nbytes, &write_size,
                         &write_buf) < 0)
            HGOTO_ERROR(H5E_HEAP, H5E_WRITEERROR, FAIL, "output pipeline failed")

        /* Use the compressed number of bytes as the size to write */
        write_size = nbytes;

        /* If the size and/or location of the on disk image of the
         * direct block changes, we must touch up its parent to reflect
         * these changes.  Do this differently depending on whether the
         * direct block's parent is an indirect block or (rarely) the
         * fractal heap header.  In this case, the direct block is known
         * as a root direct block.
         */

        /* Check for root direct block */
        if (dblock->parent == NULL) {
            hbool_t hdr_changed = FALSE; /* Whether the header info changed */

            /* Sanity check */
            HDassert(H5F_addr_eq(hdr->man_dtable.table_addr, addr));
            HDassert(hdr->pline_root_direct_size > 0);

            /* Check if the filter mask changed */
            if (hdr->pline_root_direct_filter_mask != filter_mask) {
                hdr->pline_root_direct_filter_mask = filter_mask;
                hdr_changed                        = TRUE;
            } /* end if */

            /* verify that the cache's last record of the compressed
             * size matches the heap's last record.  This value will
             * likely change shortly.
             */
            HDassert(len == hdr->pline_root_direct_size);

            /* Check if we need to re-size the block on disk */
            if (hdr->pline_root_direct_size != write_size || at_tmp_addr) {
                /* Check if the direct block is NOT currently allocated
                 * in temp. file space
                 *
                 * (temp. file space does not need to be freed)
                 */
                if (!at_tmp_addr)
                    /* Release direct block's current disk space */
                    if (H5MF_xfree(f, H5FD_MEM_FHEAP_DBLOCK, addr, (hsize_t)hdr->pline_root_direct_size) < 0)
                        HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to free fractal heap direct block")

                /* Allocate space for the compressed direct block */
                if (HADDR_UNDEF ==
                    (dblock_addr = H5MF_alloc((H5F_t *)f, H5FD_MEM_FHEAP_DBLOCK, (hsize_t)write_size)))
                    HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL,
                                "file allocation failed for fractal heap direct block")

                /* Update information about compressed direct block's
                 * location & size
                 */
                HDassert(hdr->man_dtable.table_addr == addr);
                HDassert(hdr->pline_root_direct_size == len);
                hdr->man_dtable.table_addr  = dblock_addr;
                hdr->pline_root_direct_size = write_size;

                /* Note that heap header was modified */
                hdr_changed = TRUE;
            } /* end if */

            /* Check if heap header was modified */
            if (hdr_changed)
                if (H5HF__hdr_dirty(hdr) < 0)
                    HGOTO_ERROR(H5E_HEAP, H5E_CANTDIRTY, FAIL, "can't mark heap header as dirty")
        }                                /* end if */
        else {                           /* the direct block's parent is an indirect block */
            hbool_t par_changed = FALSE; /* Whether the parent's infochanged */

            /* Sanity check */
            HDassert(par_iblock);
            HDassert(par_iblock->filt_ents[par_entry].size > 0);

            /* Check if the filter mask changed */
            if (par_iblock->filt_ents[par_entry].filter_mask != filter_mask) {
                par_iblock->filt_ents[par_entry].filter_mask = filter_mask;
                par_changed                                  = TRUE;
            } /* end if */

            /* verify that the cache's last record of the compressed
             * size matches the heap's last record.  This value will
             * likely change shortly.
             */
            HDassert(len == par_iblock->filt_ents[par_entry].size);

            /* Check if we need to re-size the block on disk */
            if (par_iblock->filt_ents[par_entry].size != write_size || at_tmp_addr) {
                /* Check if the direct block is NOT currently allocated
                 * in temp. file space
                 *
                 * (temp. file space does not need to be freed)
                 */
                if (!at_tmp_addr)
                    /* Release direct block's current disk space */
                    if (H5MF_xfree(f, H5FD_MEM_FHEAP_DBLOCK, addr,
                                   (hsize_t)par_iblock->filt_ents[par_entry].size) < 0)
                        HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to free fractal heap direct block")

                /* Allocate space for the compressed direct block */
                if (HADDR_UNDEF ==
                    (dblock_addr = H5MF_alloc((H5F_t *)f, H5FD_MEM_FHEAP_DBLOCK, (hsize_t)write_size)))
                    HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL,
                                "file allocation failed for fractal heap direct block")

                /* Update information about compressed direct block's
                 * location & size
                 */
                HDassert(par_iblock->ents[par_entry].addr == addr);
                HDassert(par_iblock->filt_ents[par_entry].size == len);
                par_iblock->ents[par_entry].addr      = dblock_addr;
                par_iblock->filt_ents[par_entry].size = write_size;

                /* Note that parent was modified */
                par_changed = TRUE;
            } /* end if */

            /* Check if parent was modified */
            if (par_changed)
                if (H5HF__iblock_dirty(par_iblock) < 0)
                    HGOTO_ERROR(H5E_HEAP, H5E_CANTDIRTY, FAIL, "can't mark heap header as dirty")
        } /* end else */
    }     /* end if */
    else {
        /* I/O filters are not enabled -- thus all we need to do is check to
         * see if the direct block is in temporary (AKA imaginary) file
         * space, and move it to real file space if it is.
         *
         * As in the I/O filters case above, we will have to touch up the
         * direct blocks parent if the direct block is relocated.
         *
         * Recall that temporary file space need not be freed, which
         * simplifies matters slightly.
         */
        write_buf  = dblock->blk;
        write_size = dblock->size;

        /* Check to see if we must re-allocate direct block from 'temp.'
         * to 'normal' file space
         */
        if (at_tmp_addr) {
            /* Allocate 'normal' space for the direct block */
            if (HADDR_UNDEF ==
                (dblock_addr = H5MF_alloc((H5F_t *)f, H5FD_MEM_FHEAP_DBLOCK, (hsize_t)write_size)))
                HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL,
                            "file allocation failed for fractal heap direct block")

            /* Check for root direct block */
            if (NULL == dblock->parent) {
                /* Sanity checks */
                HDassert(H5F_addr_eq(hdr->man_dtable.table_addr, addr));
                HDassert(!H5F_addr_eq(hdr->man_dtable.table_addr, dblock_addr));

                /* Update information about direct block's location */
                hdr->man_dtable.table_addr = dblock_addr;

                /* Mark that heap header was modified */
                if (H5HF__hdr_dirty(hdr) < 0)
                    HGOTO_ERROR(H5E_HEAP, H5E_CANTDIRTY, FAIL, "can't mark heap header as dirty")
            }      /* end if */
            else { /* the direct block's parent is an indirect block */
                /* Sanity checks */
                HDassert(par_iblock);
                HDassert(par_iblock->ents);
                HDassert(H5F_addr_eq(par_iblock->ents[par_entry].addr, addr));
                HDassert(!H5F_addr_eq(par_iblock->ents[par_entry].addr, dblock_addr));

                /* Update information about direct block's location */
                par_iblock->ents[par_entry].addr = dblock_addr;

                /* Mark that parent was modified */
                if (H5HF__iblock_dirty(par_iblock) < 0)
                    HGOTO_ERROR(H5E_HEAP, H5E_CANTDIRTY, FAIL, "can't mark heap header as dirty")
            } /* end else */
        }     /* end if */
    }         /* end else */

    /* At this point, write_buf points to a buffer containing the image
     * of the direct block that is ready to copy into the image buffer,
     * and write_size contains the length of this buffer.
     *
     * Also, if image size or address has changed, the direct block's
     * parent has been modified to reflect the change.
     *
     * Now, make note of the pointer and length of the above buffer for
     * use by the serialize function.
     */
    dblock->write_buf  = (uint8_t *)write_buf;
    dblock->write_size = write_size;

    /* finally, pass data back to the metadata cache as appropriate */
    if (!H5F_addr_eq(addr, dblock_addr)) {
        dblock_flags |= H5AC__SERIALIZE_MOVED_FLAG;
        *new_addr = dblock_addr;
    } /* end if */

    if ((hdr->filter_len > 0) && (len != write_size)) {
        dblock_flags |= H5AC__SERIALIZE_RESIZED_FLAG;
        *new_len = write_size;
    } /* end if */

    *flags = dblock_flags;

    /* final sanity check */
    HDassert(dblock->write_buf);
    HDassert(dblock->write_size > 0);

done:
    /* discard the write buf if we have an error */
    if (write_buf && (write_buf != dblock->blk) && (dblock->write_buf == NULL))
        H5MM_xfree(write_buf);

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5HF__cache_dblock_pre_serialize() */

/*-------------------------------------------------------------------------
 * Function:	H5HF__cache_dblock_serialize
 *
 * Purpose:	In principle, this function is supposed to construct the on
 *		disk image of the direct block, and place that image in the
 *		image buffer provided by the metadata cache.
 *
 *		However, since there are cases in which the pre_serialize
 *		function has to construct the on disk image to determine its size
 *		and address, this function simply copies the image prepared by
 *		the pre-serialize function into the supplied image buffer, and
 *		discards a buffer if necessary.
 *
 * Return:	Success:	SUCCEED
 *		Failure:	FAIL
 *
 * Programmer:	John Mainzer
 *		6/21/14
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5HF__cache_dblock_serialize(const H5F_t H5_ATTR_NDEBUG_UNUSED *f, void *image,
                             size_t H5_ATTR_NDEBUG_UNUSED len, void *_thing)
{
    H5HF_direct_t *dblock    = (H5HF_direct_t *)_thing; /* Direct block info */
    herr_t         ret_value = SUCCEED;                 /* Return value */

    FUNC_ENTER_PACKAGE_NOERR

    /* Sanity checks */
    HDassert(f);
    HDassert(image);
    HDassert(len > 0);
    HDassert(dblock);
    HDassert(dblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
    HDassert(dblock->cache_info.type == H5AC_FHEAP_DBLOCK);
    HDassert((dblock->blk != dblock->write_buf) || (dblock->cache_info.size == dblock->size));
    HDassert(dblock->write_buf);
    HDassert(dblock->write_size > 0);
    HDassert((dblock->blk != dblock->write_buf) || (dblock->write_size == dblock->size));
    HDassert(dblock->write_size == len);

    /* Copy the image from *(dblock->write_buf) to *image */
    H5MM_memcpy(image, dblock->write_buf, dblock->write_size);

    /* Free *(dblock->write_buf) if it was allocated by the
     * pre-serialize function
     */
    if (dblock->write_buf != dblock->blk)
        H5MM_xfree(dblock->write_buf);

    /* Reset the write_buf and write_size fields */
    dblock->write_buf  = NULL;
    dblock->write_size = 0;

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5HF__cache_dblock_serialize() */

/*-------------------------------------------------------------------------
 * Function:	H5HF__cache_dblock_notify
 *
 * Purpose:	Setup / takedown flush dependencies as direct blocks
 *		are loaded / inserted and evicted from the metadata cache.
 *
 * Return:	Success:	SUCCEED
 *		Failure:	FAIL
 *
 * Programmer:	John Mainzer
 *		6/21/14
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5HF__cache_dblock_notify(H5AC_notify_action_t action, void *_thing)
{
    H5HF_direct_t *dblock    = (H5HF_direct_t *)_thing; /* Fractal heap direct block */
    herr_t         ret_value = SUCCEED;                 /* Return value */

    FUNC_ENTER_PACKAGE

    /* Sanity checks */
    HDassert(dblock);
    HDassert(dblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
    HDassert(dblock->cache_info.type == H5AC_FHEAP_DBLOCK);
    HDassert(dblock->hdr);

    switch (action) {
        case H5AC_NOTIFY_ACTION_AFTER_INSERT:
        case H5AC_NOTIFY_ACTION_AFTER_LOAD:
            /* Create flush dependency with parent, if there is one */
            if (dblock->fd_parent)
                if (H5AC_create_flush_dependency(dblock->fd_parent, dblock) < 0)
                    HGOTO_ERROR(H5E_HEAP, H5E_CANTDEPEND, FAIL, "unable to create flush dependency")
            break;

        case H5AC_NOTIFY_ACTION_AFTER_FLUSH:
        case H5AC_NOTIFY_ACTION_ENTRY_DIRTIED:
        case H5AC_NOTIFY_ACTION_ENTRY_CLEANED:
        case H5AC_NOTIFY_ACTION_CHILD_DIRTIED:
        case H5AC_NOTIFY_ACTION_CHILD_CLEANED:
        case H5AC_NOTIFY_ACTION_CHILD_UNSERIALIZED:
        case H5AC_NOTIFY_ACTION_CHILD_SERIALIZED:
            /* do nothing */
            break;

        case H5AC_NOTIFY_ACTION_BEFORE_EVICT:
            if (dblock->fd_parent) {
                /* Destroy flush dependency with parent */
                if (H5AC_destroy_flush_dependency(dblock->fd_parent, dblock) < 0)
                    HGOTO_ERROR(H5E_HEAP, H5E_CANTUNDEPEND, FAIL, "unable to destroy flush dependency")
                dblock->fd_parent = NULL;
            } /* end if */
            break;

        default:
            HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "unknown action from metadata cache")
            break;
    } /* end switch */

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5HF__cache_dblock_notify() */

/*-------------------------------------------------------------------------
 * Function:	H5HF__cache_dblock_free_icr
 *
 * Purpose:	Free the in core memory allocated to the supplied direct
 *		block.
 *
 * Note:	The metadata cache sets the object's cache_info.magic to
 *		H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC before calling a free_icr
 *		callback (checked in assert).
 *
 * Return:	Success:	SUCCEED
 *		Failure:	FAIL
 *
 * Programmer:	John Mainzer
 *		6/21/14
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5HF__cache_dblock_free_icr(void *_thing)
{
    H5HF_direct_t *dblock    = (H5HF_direct_t *)_thing; /* Fractal heap direct block */
    herr_t         ret_value = SUCCEED;                 /* Return value */

    FUNC_ENTER_PACKAGE

    /* Sanity checks */
    HDassert(dblock);
    HDassert(dblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_BAD_MAGIC);
    HDassert(dblock->cache_info.type == H5AC_FHEAP_DBLOCK);

    /* Destroy fractal heap direct block */
    if (H5HF__man_dblock_dest(dblock) < 0)
        HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to destroy fractal heap direct block")

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5HF__cache_dblock_free_icr() */

/*-------------------------------------------------------------------------
 * Function:	H5HF__cache_dblock_fsf_size
 *
 * Purpose:     Tell the metadata cache the actual amount of file space
 *              to free when a dblock entry is destroyed with the free
 *              file space flag set.
 *
 * Return:	Success:	SUCCEED
 *		Failure:	FAIL
 *
 * Programmer:	Quincey Koziol
 *		1/5/18
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5HF__cache_dblock_fsf_size(const void *_thing, hsize_t *fsf_size)
{
    const H5HF_direct_t *dblock = (const H5HF_direct_t *)_thing; /* Fractal heap direct block */

    FUNC_ENTER_PACKAGE_NOERR

    /* Sanity checks */
    HDassert(dblock);
    HDassert(dblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
    HDassert(dblock->cache_info.type == H5AC_FHEAP_DBLOCK);
    HDassert(dblock->file_size > 0);
    HDassert(fsf_size);

    /* Set free space in file size */
    *fsf_size = dblock->file_size;

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* end H5HF__cache_dblock_fsf_size() */

/*------------------------------------------------------------------------
 * Function:	H5HF__cache_verify_hdr_descendants_clean
 *
 * Purpose:	Sanity checking routine that verifies that all indirect
 *		and direct blocks that are descendants of the supplied
 *		instance of H5HF_hdr_t are clean.  Set *clean to
 *		TRUE if this is the case, and to FALSE otherwise.
 *
 *		Update -- 8/24/15
 *
 *		With the advent of the metadata cache image feature, it is
 *		possible for the pre-serialize and serialize calls to be
 *		invoked outside of a flush.  While this serialization
 *		observes flush dependencies for the order of serialization,
 *		the entries are not written to disk, and hence dirty entries
 *		remain dirty.
 *
 *		To address this, updated the sanity checks in this function
 *		to treat entries whose images are up to date as clean if
 *		a cache serialization is in progress.
 *
 *		Update -- 9/29/16
 *
 *		The implementation of flush dependencies has been changed.
 *		Prior to this change, a flush dependency parent could be
 *		flushed if and only if all its flush dependency descendants
 *		were clean.  In the new definition, a flush dependency
 *		parent can be flushed if all its immediate flush dependency
 *		children are clean, regardless of any other dirty
 *		descendants.
 *
 *		Further, metadata cache entries are now allowed to have
 *		multiple flush dependency parents.
 *
 *		This means that the fractal heap is no longer ncessarily
 *		flushed from the bottom up.
 *
 *		For example, it is now possible for a dirty fractal heap
 *		header to be flushed before a dirty dblock, as long as the
 *		there in an interviening iblock, and the header has no
 *		dirty immediate flush dependency children.
 *
 *		Also, I gather that under some circumstances, a dblock
 *		will be direct a flush dependency child both of the iblock
 *		that points to it, and of the fractal heap header.
 *
 *		As a result of these changes, the functionality of these
 *		sanity checking routines has been modified significantly.
 *		Instead of scanning the fractal heap from a starting point
 *		down, and verifying that there were no dirty entries, the
 *		functions now scan downward from the starting point and
 *		verify that there are no dirty flush dependency children
 *		of the specified flush dependency parent.  In passing,
 *		they also walk the data structure, and verify it.
 *
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	John Mainzer
 *		5/25/14
 *
 *-------------------------------------------------------------------------
 */
#ifndef NDEBUG
static herr_t
H5HF__cache_verify_hdr_descendants_clean(H5F_t *f, H5HF_hdr_t *hdr, hbool_t *fd_clean, hbool_t *clean)
{
    hbool_t  fd_exists = FALSE;    /* whether flush dependency exists. */
    haddr_t  hdr_addr;             /* Address of header */
    unsigned hdr_status = 0;       /* Header cache entry status */
    herr_t   ret_value  = SUCCEED; /* Return value */

    FUNC_ENTER_PACKAGE

    /* Sanity checks */
    HDassert(f);
    HDassert(hdr);
    HDassert(hdr->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
    HDassert(hdr->cache_info.type == H5AC_FHEAP_HDR);
    HDassert(fd_clean);
    HDassert(clean);
    hdr_addr = hdr->cache_info.addr;
    HDassert(hdr_addr == hdr->heap_addr);

    if (H5AC_get_entry_status(f, hdr_addr, &hdr_status) < 0)
        HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL, "can't get hdr status")
    HDassert(hdr_status & H5AC_ES__IN_CACHE);

    /* We have three basic scenarios we have to deal with:
     *
     * The first, and most common case, is that there is a root iblock.
     * In this case we need to verify that the root iblock and all its
     * children are clean.
     *
     * The second, and much less common case, is that in which the
     * the fractal heap contains only one direct block, which is
     * pointed to by hdr->man_dtable.table_addr.  In this case, all we
     * need to do is verify that the root direct block is clean.
     *
     * Finally, it is possible that the fractal heap is empty, and
     * has neither a root indirect block nor a root direct block.
     * In this case, we have nothing to do.
     */

    /* There are two ways in which we can arrive at the first scenario.
     *
     * By far the most common is when hdr->root_iblock contains a pointer
     * to the root iblock -- in this case the root iblock is almost certainly
     * pinned, although we can't count on that.
     *
     * However, it is also possible that there is a root iblock that
     * is no longer pointed to by the header.  In this case, the on
     * disk address of the iblock will be in hdr->man_dtable.table_addr
     * and hdr->man_dtable.curr_root_rows will contain a positive value.
     *
     * Since the former case is far and away the most common, we don't
     * worry too much about efficiency in the second case.
     */
    if (hdr->root_iblock ||
        ((hdr->man_dtable.curr_root_rows > 0) && (HADDR_UNDEF != hdr->man_dtable.table_addr))) {
        H5HF_indirect_t *root_iblock = hdr->root_iblock;
        haddr_t          root_iblock_addr;
        unsigned         root_iblock_status = 0;
        hbool_t          root_iblock_in_cache;

        /* make note of the on disk address of the root iblock */
        if (root_iblock == NULL)
            /* hdr->man_dtable.table_addr must contain address of root
             * iblock.  Check to see if it is in cache.  If it is,
             * protect it and put its address in root_iblock.
             */
            root_iblock_addr = hdr->man_dtable.table_addr;
        else
            root_iblock_addr = root_iblock->addr;

        /* get the status of the root iblock */
        HDassert(root_iblock_addr != HADDR_UNDEF);
        if (H5AC_get_entry_status(f, root_iblock_addr, &root_iblock_status) < 0)
            HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL, "can't get root iblock status")

        root_iblock_in_cache = ((root_iblock_status & H5AC_ES__IN_CACHE) != 0);
        HDassert(root_iblock_in_cache || (root_iblock == NULL));

        if (!root_iblock_in_cache) { /* we are done */
            *clean    = TRUE;
            *fd_clean = TRUE;
        } /* end if */
        else if ((root_iblock_status & H5AC_ES__IS_DIRTY) &&
                 (((root_iblock_status & H5AC_ES__IMAGE_IS_UP_TO_DATE) == 0) ||
                  (!H5AC_get_serialization_in_progress(f)))) {
            *clean = FALSE;

            /* verify that a flush dependency exists between the header and
             * the root inode.
             */
            if (H5AC_flush_dependency_exists(f, hdr->heap_addr, root_iblock_addr, &fd_exists) < 0)
                HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL, "can't check flush dependency")
            HDassert(fd_exists);

            *fd_clean = FALSE;
        }      /* end else-if */
        else { /* must examine children */
            hbool_t unprotect_root_iblock = FALSE;

            /* At this point, the root iblock may be pinned, protected,
             * both, or neither, and we may or may not have a pointer
             * to root iblock in memory.
             *
             * Before we call H5HF__cache_verify_iblock_descendants_clean(),
             * we must ensure that the root iblock is either pinned or
             * protected or both, and that we have a pointer to it.
             * Do this as follows:
             */
            if (root_iblock == NULL) { /* we don't have ptr to root iblock */
                if (0 == (root_iblock_status & H5AC_ES__IS_PROTECTED)) {
                    /* just protect the root iblock -- this will give us
                     * the pointer we need to proceed, and ensure that
                     * it is locked into the metadata cache for the
                     * duration.
                     *
                     * Note that the udata is only used in the load callback.
                     * While the fractal heap makes heavy use of the udata
                     * in this case, since we know that the entry is in cache,
                     * we can pass NULL udata.
                     *
                     * The tag specified in the API context we received
                     * as a parameter (via API context) may not be correct.
                     * Grab the (hopefully) correct tag from the header,
                     * and load it into the API context via the H5_BEGIN_TAG and
                     * H5_END_TAG macros.  Note that any error bracked by
                     * these macros must be reported with HGOTO_ERROR_TAG.
                     */
                    H5_BEGIN_TAG(hdr->heap_addr)

                    if (NULL == (root_iblock = (H5HF_indirect_t *)H5AC_protect(
                                     f, H5AC_FHEAP_IBLOCK, root_iblock_addr, NULL, H5AC__READ_ONLY_FLAG)))
                        HGOTO_ERROR_TAG(H5E_HEAP, H5E_CANTPROTECT, FAIL, "H5AC_protect() failed.")

                    H5_END_TAG

                    unprotect_root_iblock = TRUE;
                } /* end if */
                else {
                    /* the root iblock is protected, and we have no
                     * legitimate way of getting a pointer to it.
                     *
                     * We square this circle by using the
                     * H5AC_get_entry_ptr_from_addr() to get the needed
                     * pointer.
                     *
                     * WARNING: This call should be used only in debugging
                     *          routines, and it should be avoided there when
                     *          possible.
                     *
                     *          Further, if we ever multi-thread the cache,
                     *          this routine will have to be either discarded
                     *          or heavily re-worked.
                     *
                     *          Finally, keep in mind that the entry whose
                     *          pointer is obtained in this fashion may not
                     *          be in a stable state.
                     *
                     * Assuming that the flush dependency code is working
                     * as it should, the only reason for the root iblock to
                     * be unpinned is if none of its children are in cache.
                     * This unfortunately means that if it is protected and
                     * not pinned, the fractal heap is in the process of loading
                     * or inserting one of its children.  The obvious
                     * implication is that there is a significant chance that
                     * the root iblock is in an unstable state.
                     *
                     * All this suggests that using
                     * H5AC_get_entry_ptr_from_addr() to obtain the pointer
                     * to the protected root iblock is questionable here.
                     * However, since this is test/debugging code, I expect
                     * that we will use this approach until it causes problems,
                     *  or we think of a better way.
                     */
                    if (H5AC_get_entry_ptr_from_addr(f, root_iblock_addr, (void **)(&root_iblock)) < 0)
                        HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL, "H5AC_get_entry_ptr_from_addr() failed.")
                    HDassert(root_iblock);
                }  /* end else */
            }      /* end if */
            else { /* root_iblock != NULL */
                   /* we have the pointer to the root iblock.  Protect it
                    * if it is neither pinned nor protected -- otherwise we
                    * are ready to go.
                    */
                H5HF_indirect_t *iblock = NULL;

                if (((root_iblock_status & H5AC_ES__IS_PINNED) == 0) &&
                    ((root_iblock_status & H5AC_ES__IS_PROTECTED) == 0)) {
                    /* the root iblock is neither pinned nor protected -- hence
                     * we must protect it before we proceed
                     *
                     * Note that the udata is only used in the load callback.
                     * While the fractal heap makes heavy use of the udata
                     * in this case, since we know that the entry is in cache,
                     * we can pass NULL udata.
                     *
                     * The tag associated specified in the API context we received
                     * as a parameter (via API context) may not be correct.
                     * Grab the (hopefully) correct tag from the header,
                     * and load it into the API context via the H5_BEGIN_TAG and
                     * H5_END_TAG macros.  Note that any error bracked by
                     * these macros must be reported with HGOTO_ERROR_TAG.
                     */
                    H5_BEGIN_TAG(hdr->heap_addr)

                    if (NULL == (iblock = (H5HF_indirect_t *)H5AC_protect(
                                     f, H5AC_FHEAP_IBLOCK, root_iblock_addr, NULL, H5AC__READ_ONLY_FLAG)))
                        HGOTO_ERROR_TAG(H5E_HEAP, H5E_CANTPROTECT, FAIL, "H5AC_protect() failed.")

                    H5_END_TAG

                    unprotect_root_iblock = TRUE;
                    HDassert(iblock == root_iblock);
                } /* end if */
            }     /* end else */

            /* at this point, one way or another, the root iblock is locked
             * in memory for the duration of the call.  Do some sanity checks,
             * and then call H5HF__cache_verify_iblock_descendants_clean().
             */
            HDassert(root_iblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
            HDassert(root_iblock->cache_info.type == H5AC_FHEAP_IBLOCK);

            if (H5HF__cache_verify_iblock_descendants_clean(f, hdr->heap_addr, root_iblock,
                                                            &root_iblock_status, fd_clean, clean) < 0)
                HGOTO_ERROR(H5E_HEAP, H5E_SYSTEM, FAIL, "can't verify root iblock & descendants clean.")

            /* Unprotect the root indirect block if required */
            if (unprotect_root_iblock) {
                HDassert(root_iblock);
                if (H5AC_unprotect(f, H5AC_FHEAP_IBLOCK, root_iblock_addr, root_iblock, H5AC__NO_FLAGS_SET) <
                    0)
                    HGOTO_ERROR(H5E_HEAP, H5E_CANTUNPROTECT, FAIL, "H5AC_unprotect() failed.")
            } /* end if */
        }     /* end else */
    }         /* end if */
    else if ((hdr->man_dtable.curr_root_rows == 0) && (HADDR_UNDEF != hdr->man_dtable.table_addr)) {
        haddr_t  root_dblock_addr;
        unsigned root_dblock_status = 0;
        hbool_t  in_cache;
        hbool_t  type_ok;

        /* this is scenario 2 -- we have a root dblock */
        root_dblock_addr = hdr->man_dtable.table_addr;
        if (H5AC_get_entry_status(f, root_dblock_addr, &root_dblock_status) < 0)
            HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL, "can't get root dblock status")

        if (root_dblock_status & H5AC_ES__IN_CACHE) {
            if (H5AC_verify_entry_type(f, root_dblock_addr, &H5AC_FHEAP_DBLOCK[0], &in_cache, &type_ok) < 0)
                HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL, "can't check dblock type")
            HDassert(in_cache);
            if (!type_ok)
                HGOTO_ERROR(H5E_HEAP, H5E_SYSTEM, FAIL, "root dblock addr doesn't refer to a dblock?!?")

            /* If a root dblock is in cache, it must have a flush
             * dependency relationship with the header, and it
             * may not be the parent in any flush dependency
             * relationship.
             *
             * We don't test this fully, but we will verify that
             * the root iblock is a child in a flush dependency
             * relationship with the header.
             */
            if (H5AC_flush_dependency_exists(f, hdr->heap_addr, root_dblock_addr, &fd_exists) < 0)
                HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL, "can't check flush dependency")
            if (!fd_exists)
                HGOTO_ERROR(H5E_HEAP, H5E_SYSTEM, FAIL, "root dblock is not a flush dep parent of header.")

            if (0 != (root_dblock_status & H5AC_ES__IS_FLUSH_DEP_PARENT))
                HGOTO_ERROR(H5E_HEAP, H5E_SYSTEM, FAIL, "root dblock in cache and is a flush dep parent.")

            *clean = !((root_dblock_status & H5AC_ES__IS_DIRTY) &&
                       (((root_dblock_status & H5AC_ES__IMAGE_IS_UP_TO_DATE) == 0) ||
                        (!H5AC_get_serialization_in_progress(f))));

            *fd_clean = *clean;
        }      /* end if */
        else { /* root dblock not in cache */
            *fd_clean = TRUE;
            *clean    = TRUE;
        } /* end else */
    }     /* end else-if */
    else {
        /* this is scenario 3 -- the fractal heap is empty, and we
         * have nothing to do.
         */
        *fd_clean = TRUE;
        *clean    = TRUE;
    } /* end else */

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* H5HF__cache_verify_hdr_descendants_clean() */
#endif /* NDEBUG */

/*------------------------------------------------------------------------
 * Function:	H5HF__cache_verify_iblock_descendants_clean
 *
 * Purpose:	Sanity checking routine that verifies that all indirect
 *		and direct blocks that are descendants of the supplied
 *		instance of H5HF_indirect_t are clean.  Set *clean
 *		to TRUE if this is the case, and to FALSE otherwise.
 *
 *		In passing, the function also does a cursory check to
 *		spot any obvious errors in the flush dependency setup.
 *		If any problems are found, the function returns failure.
 *		Note that these checks are not exhaustive, thus passing
 *		them does not mean that the flush dependencies are
 *		correct -- only that there is nothing obviously wrong
 *		with them.
 *
 *		WARNING:  At its top level call, this function is
 *		intended to be called from H5HF_cache_iblock_flush(),
 *		and thus presumes that the supplied indirect block
 *		is in cache.  Any other use of this function and
 *		its descendants must insure that this assumption is
 *		met.
 *
 *		Note that this function and
 *		H5HF__cache_verify_descendant_iblocks_clean() are
 *		recursive co-routines.
 *
 *		Update -- 9/29/16
 *
 *		The implementation of flush dependencies has been changed.
 *		Prior to this change, a flush dependency parent could be
 *		flushed if and only if all its flush dependency descendants
 *		were clean.  In the new definition, a flush dependency
 *		parent can be flushed if all its immediate flush dependency
 *		children are clean, regardless of any other dirty
 *		descendants.
 *
 *		Further, metadata cache entries are now allowed to have
 *		multiple flush dependency parents.
 *
 *		This means that the fractal heap is no longer ncessarily
 *		flushed from the bottom up.
 *
 *		For example, it is now possible for a dirty fractal heap
 *		header to be flushed before a dirty dblock, as long as the
 *		there in an interviening iblock, and the header has no
 *		dirty immediate flush dependency children.
 *
 *		Also, I gather that under some circumstances, a dblock
 *		will be direct a flush dependency child both of the iblock
 *		that points to it, and of the fractal heap header.
 *
 *		As a result of these changes, the functionality of these
 *		sanity checking routines has been modified significantly.
 *		Instead of scanning the fractal heap from a starting point
 *		down, and verifying that there were no dirty entries, the
 *		functions now scan downward from the starting point and
 *		verify that there are no dirty flush dependency children
 *		of the specified flush dependency parent.  In passing,
 *		they also walk the data structure, and verify it.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	John Mainzer
 *		5/25/14
 *
 *-------------------------------------------------------------------------
 */
#ifndef NDEBUG
static herr_t
H5HF__cache_verify_iblock_descendants_clean(H5F_t *f, haddr_t fd_parent_addr, H5HF_indirect_t *iblock,
                                            unsigned *iblock_status, hbool_t *fd_clean, hbool_t *clean)
{
    hbool_t has_dblocks = FALSE;
    hbool_t has_iblocks = FALSE;
    herr_t  ret_value   = SUCCEED; /* Return value */

    FUNC_ENTER_PACKAGE

    /* Sanity checks */
    HDassert(f);
    HDassert(H5F_addr_defined(fd_parent_addr));
    HDassert(iblock);
    HDassert(iblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
    HDassert(iblock->cache_info.type == H5AC_FHEAP_IBLOCK);
    HDassert(iblock_status);
    HDassert(fd_clean);
    HDassert(*fd_clean);
    HDassert(clean); /* note that *clean need not be TRUE */

    if ((*fd_clean) && H5HF__cache_verify_iblocks_dblocks_clean(f, fd_parent_addr, iblock, fd_clean, clean,
                                                                &has_dblocks) < 0)
        HGOTO_ERROR(H5E_HEAP, H5E_SYSTEM, FAIL, "can't verify dblocks clean.")

    if ((*fd_clean) && H5HF__cache_verify_descendant_iblocks_clean(f, fd_parent_addr, iblock, fd_clean, clean,
                                                                   &has_iblocks) < 0)
        HGOTO_ERROR(H5E_HEAP, H5E_SYSTEM, FAIL, "can't verify iblocks clean.")

    /* verify that flush dependency setup is plausible */
    if (0 == (*iblock_status & H5AC_ES__IS_FLUSH_DEP_CHILD))
        HGOTO_ERROR(H5E_HEAP, H5E_SYSTEM, FAIL, "iblock is not a flush dep child.")
    if (((has_dblocks || has_iblocks)) && (0 == (*iblock_status & H5AC_ES__IS_FLUSH_DEP_PARENT)))
        HGOTO_ERROR(H5E_HEAP, H5E_SYSTEM, FAIL, "iblock has children and is not a flush dep parent.")
    if (((has_dblocks || has_iblocks)) && (0 == (*iblock_status & H5AC_ES__IS_PINNED)))
        HGOTO_ERROR(H5E_HEAP, H5E_SYSTEM, FAIL, "iblock has children and is not pinned.")

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* H5HF__cache_verify_iblock_descendants_clean() */
#endif /* NDEBUG */

/*------------------------------------------------------------------------
 * Function:	H5HF__cache_verify_iblocks_dblocks_clean
 *
 * Purpose:	Sanity checking routine that attempts to verify that all
 *		direct blocks pointed to by the supplied indirect block
 *		are either clean, or not in the cache.
 *
 *		In passing, the function also does a cursory check to
 *		spot any obvious errors in the flush dependency setup.
 *		If any problems are found, the function returns failure.
 *		Note that these checks are not exhaustive, thus passing
 *		them does not mean that the flush dependencies are
 *		correct -- only that there is nothing obviously wrong
 *		with them.
 *
 *		WARNING:  This function presumes that the supplied
 *		iblock is in the cache, and will not be removed
 *		during the call.  Caller must ensure that this is
 *		the case before the call.
 *
 *      Update -- 8/24/15
 *
 *      With the advent of the metadata cache image feature, it is
 *      possible for the pre-serialize and serialize calls to be
 *      invoked outside of a flush.  While this serialization
 *      observes flush dependencies for the order of serialization,
 *      the entries are not written to disk, and hence dirty entries
 *      remain dirty.
 *
 *      To address this, updated the sanity checks in this function
 *      to treat entries whose images are up to date as clean if
 *      a cache serialization is in progress.
 *
 *		Update -- 9/29/16
 *
 *		The implementation of flush dependencies has been changed.
 *		Prior to this change, a flush dependency parent could be
 *		flushed if and only if all its flush dependency descendants
 *		were clean.  In the new definition, a flush dependency
 *		parent can be flushed if all its immediate flush dependency
 *		children are clean, regardless of any other dirty
 *		descendants.
 *
 *		Further, metadata cache entries are now allowed to have
 *		multiple flush dependency parents.
 *
 *		This means that the fractal heap is no longer ncessarily
 *		flushed from the bottom up.
 *
 *		For example, it is now possible for a dirty fractal heap
 *		header to be flushed before a dirty dblock, as long as the
 *		there in an interviening iblock, and the header has no
 *		dirty immediate flush dependency children.
 *
 *		Also, I gather that under some circumstances, a dblock
 *		will be direct a flush dependency child both of the iblock
 *		that points to it, and of the fractal heap header.
 *
 *		As a result of these changes, the functionality of these
 *		sanity checking routines has been modified significantly.
 *		Instead of scanning the fractal heap from a starting point
 *		down, and verifying that there were no dirty entries, the
 *		functions now scan downward from the starting point and
 *		verify that there are no dirty flush dependency children
 *		of the specified flush dependency parent.  In passing,
 *		they also walk the data structure, and verify it.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	John Mainzer
 *		5/25/14
 *
 *-------------------------------------------------------------------------
 */
#ifndef NDEBUG
static herr_t
H5HF__cache_verify_iblocks_dblocks_clean(H5F_t *f, haddr_t fd_parent_addr, H5HF_indirect_t *iblock,
                                         hbool_t *fd_clean, hbool_t *clean, hbool_t *has_dblocks)
{
    unsigned num_direct_rows;
    unsigned max_dblock_index;
    unsigned i;
    haddr_t  iblock_addr;
    herr_t   ret_value = SUCCEED; /* Return value */

    FUNC_ENTER_PACKAGE

    /* Sanity checks */
    HDassert(f);
    HDassert(H5F_addr_defined(fd_parent_addr));
    HDassert(iblock);
    HDassert(iblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
    HDassert(iblock->cache_info.type == H5AC_FHEAP_IBLOCK);
    HDassert(fd_clean);
    HDassert(*fd_clean);
    HDassert(clean); /* note that *clean need not be true */
    HDassert(has_dblocks);

    i               = 0;
    num_direct_rows = MIN(iblock->nrows, iblock->hdr->man_dtable.max_direct_rows);
    HDassert(num_direct_rows <= iblock->nrows);
    max_dblock_index = (num_direct_rows * iblock->hdr->man_dtable.cparam.width) - 1;
    iblock_addr      = iblock->addr;
    HDassert(H5F_addr_defined(iblock_addr));

    while ((*fd_clean) && (i <= max_dblock_index)) {
        haddr_t dblock_addr;

        dblock_addr = iblock->ents[i].addr;
        if (H5F_addr_defined(dblock_addr)) {
            hbool_t in_cache;
            hbool_t type_ok;

            if (H5AC_verify_entry_type(f, dblock_addr, &H5AC_FHEAP_DBLOCK[0], &in_cache, &type_ok) < 0)
                HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL, "can't check dblock type")

            if (in_cache) { /* dblock is in cache */
                hbool_t  fd_exists;
                unsigned dblock_status = 0;

                if (!type_ok)
                    HGOTO_ERROR(H5E_HEAP, H5E_SYSTEM, FAIL, "dblock addr doesn't refer to a dblock?!?")

                if (H5AC_get_entry_status(f, dblock_addr, &dblock_status) < 0)
                    HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL, "can't get dblock status")

                HDassert(dblock_status & H5AC_ES__IN_CACHE);

                *has_dblocks = TRUE;

                if ((dblock_status & H5AC_ES__IS_DIRTY) &&
                    (((dblock_status & H5AC_ES__IMAGE_IS_UP_TO_DATE) == 0) ||
                     (!H5AC_get_serialization_in_progress(f)))) {
                    *clean = FALSE;

                    if (H5AC_flush_dependency_exists(f, fd_parent_addr, dblock_addr, &fd_exists) < 0)
                        HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL, "can't check flush dependency")

                    if (fd_exists)
                        *fd_clean = FALSE;
                } /* end if */

                /* If a child dblock is in cache, it must have a flush
                 * dependency relationship with this iblock.  Test this
                 * here.
                 */
                if (H5AC_flush_dependency_exists(f, iblock_addr, dblock_addr, &fd_exists) < 0)
                    HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL, "can't check flush dependency")

                if (!fd_exists)
                    HGOTO_ERROR(H5E_HEAP, H5E_SYSTEM, FAIL,
                                "dblock in cache and not a flush dep child of iblock.")
            } /* end if */
        }     /* end if */

        i++;
    } /* end while */

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* H5HF__cache_verify_iblocks_dblocks_clean() */
#endif /* NDEBUG */

/*------------------------------------------------------------------------
 * Function:	H5HF__cache_verify_descendant_iblocks_clean
 *
 * Purpose:	Sanity checking routine that attempts to verify that all
 *		direct blocks pointed to by the supplied indirect block
 *		are either clean, or not in the cache.
 *
 *		In passing, the function also does a cursory check to
 *		spot any obvious errors in the flush dependency setup.
 *		If any problems are found, the function returns failure.
 *		Note that these checks are not exhaustive, thus passing
 *		them does not mean that the flush dependencies are
 *		correct -- only that there is nothing obviously wrong
 *		with them.
 *
 *		WARNING:  This function presumes that the supplied
 *		iblock is in the cache, and will not be removed
 *		during the call.  Caller must ensure that this is
 *		the case before the call.
 *
 *              Update -- 8/24/15
 *
 *              With the advent of the metadata cache image feature, it is
 *              possible for the pre-serialize and serialize calls to be
 *              invoked outside of a flush.  While this serialization
 *              observes flush dependencies for the order of serialization,
 *              the entries are not written to disk, and hence dirty entries
 *              remain dirty.
 *
 *              To address this, updated the sanity checks in this function
 *              to treat entries whose images are up to date as clean if
 *              a cache serialization is in progress.
 *
 *		Update -- 9/29/16
 *
 *		The implementation of flush dependencies has been changed.
 *		Prior to this change, a flush dependency parent could be
 *		flushed if and only if all its flush dependency descendants
 *		were clean.  In the new definition, a flush dependency
 *		parent can be flushed if all its immediate flush dependency
 *		children are clean, regardless of any other dirty
 *		descendants.
 *
 *		Further, metadata cache entries are now allowed to have
 *		multiple flush dependency parents.
 *
 *		This means that the fractal heap is no longer ncessarily
 *		flushed from the bottom up.
 *
 *		For example, it is now possible for a dirty fractal heap
 *		header to be flushed before a dirty dblock, as long as the
 *		there in an interviening iblock, and the header has no
 *		dirty immediate flush dependency children.
 *
 *		Also, I gather that under some circumstances, a dblock
 *		will be direct a flush dependency child both of the iblock
 *		that points to it, and of the fractal heap header.
 *
 *		As a result of these changes, the functionality of these
 *		sanity checking routines has been modified significantly.
 *		Instead of scanning the fractal heap from a starting point
 *		down, and verifying that there were no dirty entries, the
 *		functions now scan downward from the starting point and
 *		verify that there are no dirty flush dependency children
 *		of the specified flush dependency parent.  In passing,
 *		they also walk the data structure, and verify it.
 *
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	John Mainzer
 *		5/25/14
 *
 *-------------------------------------------------------------------------
 */
#ifndef NDEBUG
static herr_t
H5HF__cache_verify_descendant_iblocks_clean(H5F_t *f, haddr_t fd_parent_addr, H5HF_indirect_t *iblock,
                                            hbool_t *fd_clean, hbool_t *clean, hbool_t *has_iblocks)
{
    unsigned first_iblock_index;
    unsigned last_iblock_index;
    unsigned num_direct_rows;
    unsigned i;
    haddr_t  iblock_addr;
    herr_t   ret_value = SUCCEED; /* Return value */

    FUNC_ENTER_PACKAGE

    /* Sanity checks */
    HDassert(f);
    HDassert(H5F_addr_defined(fd_parent_addr));
    HDassert(iblock);
    HDassert(iblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
    HDassert(iblock->cache_info.type == H5AC_FHEAP_IBLOCK);
    HDassert(fd_clean);
    HDassert(*fd_clean);
    HDassert(clean); /* note that *clean need not be true */
    HDassert(has_iblocks);
    num_direct_rows = MIN(iblock->nrows, iblock->hdr->man_dtable.max_direct_rows);
    HDassert(num_direct_rows <= iblock->nrows);

    iblock_addr        = iblock->addr;
    first_iblock_index = num_direct_rows * iblock->hdr->man_dtable.cparam.width;
    last_iblock_index  = (iblock->nrows * iblock->hdr->man_dtable.cparam.width) - 1;

    i = first_iblock_index;
    while ((*fd_clean) && (i <= last_iblock_index)) {
        haddr_t child_iblock_addr = iblock->ents[i].addr;

        if (H5F_addr_defined(child_iblock_addr)) {
            unsigned child_iblock_status = 0;

            if (H5AC_get_entry_status(f, child_iblock_addr, &child_iblock_status) < 0)
                HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL, "can't get iblock status")

            if (child_iblock_status & H5AC_ES__IN_CACHE) {
                hbool_t fd_exists;

                *has_iblocks = TRUE;

                if ((child_iblock_status & H5AC_ES__IS_DIRTY) &&
                    (((child_iblock_status & H5AC_ES__IMAGE_IS_UP_TO_DATE) == 0) ||
                     (!H5AC_get_serialization_in_progress(f)))) {

                    *clean = FALSE;

                    if (H5AC_flush_dependency_exists(f, fd_parent_addr, child_iblock_addr, &fd_exists) < 0)
                        HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL, "can't check flush dependency")

                    if (fd_exists)
                        *fd_clean = FALSE;
                } /* end if */

                /* if the child iblock is in cache and *fd_clean is TRUE,
                 * we must continue to explore down the fractal heap tree
                 * structure to verify that all descendant blocks that are
                 * flush dependency children of the entry at parent_addr are
                 * either clean, or not in the metadata cache.  We do this
                 * with a recursive call to
                 * H5HF__cache_verify_iblock_descendants_clean().
                 * However, we can't make this call unless the child iblock
                 * is somehow locked into the cache -- typically via either
                 * pinning or protecting.
                 *
                 * If the child iblock is pinned, we can look up its pointer
                 * on the current iblock's pinned child iblock list, and
                 * and use that pointer in the recursive call.
                 *
                 * If the entry is unprotected and unpinned, we simply
                 * protect it.
                 *
                 * If, however, the the child iblock is already protected,
                 * but not pinned, we have a bit of a problem, as we have
                 * no legitimate way of looking up its pointer in memory.
                 *
                 * To solve this problem, I have added a new metadata cache
                 * call to obtain the pointer.
                 *
                 * WARNING: This call should be used only in debugging
                 * 	    routines, and it should be avoided there when
                 *	    possible.
                 *
                 *          Further, if we ever multi-thread the cache,
                 *	    this routine will have to be either discarded
                 *	    or heavily re-worked.
                 *
                 *	    Finally, keep in mind that the entry whose
                 *	    pointer is obtained in this fashion may not
                 *          be in a stable state.
                 *
                 * Assuming that the flush dependency code is working
                 * as it should, the only reason for the child entry to
                 * be unpinned is if none of its children are in cache.
                 * This unfortunately means that if it is protected and
                 * not pinned, the fractal heap is in the process of loading
                 * or inserting one of its children.  The obvious implication
                 * is that there is a significant chance that the child
                 * iblock is in an unstable state.
                 *
                 * All this suggests that using the new call to obtain the
                 * pointer to the protected child iblock is questionable
                 * here.  However, since this is test/debugging code, I
                 * expect that we will use this approach until it causes
                 * problems, or we think of a better way.
                 */
                if (*fd_clean) {
                    H5HF_indirect_t *child_iblock           = NULL;
                    hbool_t          unprotect_child_iblock = FALSE;

                    if (0 == (child_iblock_status & H5AC_ES__IS_PINNED)) {
                        /* child iblock is not pinned */
                        if (0 == (child_iblock_status & H5AC_ES__IS_PROTECTED)) {
                            /* child iblock is unprotected, and unpinned */
                            /* protect it.  Note that the udata is only  */
                            /* used in the load callback.  While the     */
                            /* fractal heap makes heavy use of the udata */
                            /* in this case, since we know that the      */
                            /* entry is in cache, we can pass NULL udata */
                            /*                                           */
                            /* The tag associated specified in the API context  */
                            /* we received as a parameter (via API context)  */
                            /* may not be correct.                       */
                            /*                                           */
                            /* Grab the (hopefully) correct tag from the */
                            /* parent iblock, and load it into the API context  */
                            /* via the H5_BEGIN_TAG and H5_END_TAG       */
                            /* macros.  Note that any error bracked by   */
                            /* these macros must be reported with        */
                            /* HGOTO_ERROR_TAG.                          */

                            H5_BEGIN_TAG(iblock->hdr->heap_addr)

                            if (NULL ==
                                (child_iblock = (H5HF_indirect_t *)H5AC_protect(
                                     f, H5AC_FHEAP_IBLOCK, child_iblock_addr, NULL, H5AC__READ_ONLY_FLAG)))
                                HGOTO_ERROR_TAG(H5E_HEAP, H5E_CANTPROTECT, FAIL, "H5AC_protect() failed.")

                            H5_END_TAG

                            unprotect_child_iblock = TRUE;
                        } /* end if */
                        else {
                            /* child iblock is protected -- use             */
                            /* H5AC_get_entry_ptr_from_addr() to get a      */
                            /* pointer to the entry.  This is very slimy -- */
                            /* come up with a better solution.              */
                            if (H5AC_get_entry_ptr_from_addr(f, child_iblock_addr, (void **)(&child_iblock)) <
                                0)
                                HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL,
                                            "H5AC_get_entry_ptr_from_addr() failed.")
                            HDassert(child_iblock);
                        } /* end else */
                    }     /* end if */
                    else {
                        /* child iblock is pinned -- look it up in the */
                        /* parent iblocks child_iblocks array.         */
                        HDassert(iblock->child_iblocks);
                        child_iblock = iblock->child_iblocks[i - first_iblock_index];
                    } /* end else */

                    /* At this point, one way or another we should have
                     * a pointer to the child iblock.  Verify that we
                     * that we have the correct one.
                     */
                    HDassert(child_iblock);
                    HDassert(child_iblock->cache_info.magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
                    HDassert(child_iblock->cache_info.type == H5AC_FHEAP_IBLOCK);
                    HDassert(child_iblock->addr == child_iblock_addr);

                    /* now make the recursive call */
                    if (H5HF__cache_verify_iblock_descendants_clean(
                            f, fd_parent_addr, child_iblock, &child_iblock_status, fd_clean, clean) < 0)
                        HGOTO_ERROR(H5E_HEAP, H5E_SYSTEM, FAIL, "can't verify child iblock clean.")

                    /* if iblock_addr != fd_parent_addr, verify that a flush
                     * dependency relationship exists between iblock and
                     * the child iblock.
                     */
                    if (fd_parent_addr != iblock_addr) {
                        if (H5AC_flush_dependency_exists(f, iblock_addr, child_iblock_addr, &fd_exists) < 0)
                            HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL, "can't check flush dependency")

                        if (!fd_exists)
                            HGOTO_ERROR(H5E_HEAP, H5E_SYSTEM, FAIL,
                                        "iblock is not a flush dep parent of child_iblock.")
                    } /* end if */

                    /* if we protected the child iblock, unprotect it now */
                    if (unprotect_child_iblock) {
                        if (H5AC_unprotect(f, H5AC_FHEAP_IBLOCK, child_iblock_addr, child_iblock,
                                           H5AC__NO_FLAGS_SET) < 0)
                            HGOTO_ERROR(H5E_HEAP, H5E_CANTUNPROTECT, FAIL, "H5AC_unprotect() failed.")
                    } /* end if */
                }     /* end if */
            }         /* end if */
        }             /* end if */

        i++;
    } /* end while */

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* H5HF__cache_verify_descendant_iblocks_clean() */
#endif /* NDEBUG */