summaryrefslogtreecommitdiffstats
path: root/fs/nfsd/nfs4state.c
blob: f19ed866c95fd18ef5da370b9cd09387c6d71c8a (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
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
3626
3627
3628
3629
3630
3631
3632
3633
3634
3635
3636
3637
3638
3639
3640
3641
3642
3643
3644
3645
3646
3647
3648
3649
3650
3651
3652
3653
3654
3655
3656
3657
3658
3659
3660
3661
3662
3663
3664
3665
3666
3667
3668
3669
3670
3671
3672
3673
3674
3675
3676
3677
3678
3679
3680
3681
3682
3683
3684
3685
3686
3687
3688
3689
3690
3691
3692
3693
3694
3695
3696
3697
3698
3699
3700
3701
3702
3703
3704
3705
3706
3707
3708
3709
3710
3711
3712
3713
3714
3715
3716
3717
3718
3719
3720
3721
3722
3723
3724
3725
3726
3727
3728
3729
3730
3731
3732
3733
3734
3735
3736
3737
3738
3739
3740
3741
3742
3743
3744
3745
3746
3747
3748
3749
3750
3751
3752
3753
3754
3755
3756
3757
3758
3759
3760
3761
3762
3763
3764
3765
3766
3767
3768
3769
3770
3771
3772
3773
3774
3775
3776
3777
3778
3779
3780
3781
3782
3783
3784
3785
3786
3787
3788
3789
3790
3791
3792
3793
3794
3795
3796
3797
3798
3799
3800
3801
3802
3803
3804
3805
3806
3807
3808
3809
3810
3811
3812
3813
3814
3815
3816
3817
3818
3819
3820
3821
3822
3823
3824
3825
3826
3827
3828
3829
3830
3831
3832
3833
3834
3835
3836
3837
3838
3839
3840
3841
3842
3843
3844
3845
3846
3847
3848
3849
3850
3851
3852
3853
3854
3855
3856
3857
3858
3859
3860
3861
3862
3863
3864
3865
3866
3867
3868
3869
3870
3871
3872
3873
3874
3875
3876
3877
3878
3879
3880
3881
3882
3883
3884
3885
3886
3887
3888
3889
3890
3891
3892
3893
3894
3895
3896
3897
3898
3899
3900
3901
3902
3903
3904
3905
3906
3907
3908
3909
3910
3911
3912
3913
3914
3915
3916
3917
3918
3919
3920
3921
3922
3923
3924
3925
3926
3927
3928
3929
3930
3931
3932
3933
3934
3935
3936
3937
3938
3939
3940
3941
3942
3943
3944
3945
3946
3947
3948
3949
3950
3951
3952
3953
3954
3955
3956
3957
3958
3959
3960
3961
3962
3963
3964
3965
3966
3967
3968
3969
3970
3971
3972
3973
3974
3975
3976
3977
3978
3979
3980
3981
3982
3983
3984
3985
3986
3987
3988
3989
3990
3991
3992
3993
3994
3995
3996
3997
3998
3999
4000
4001
4002
4003
4004
4005
4006
4007
4008
4009
4010
4011
4012
4013
4014
4015
4016
4017
4018
4019
4020
4021
4022
4023
4024
4025
4026
4027
4028
4029
4030
4031
4032
4033
4034
4035
4036
4037
4038
4039
4040
4041
4042
4043
4044
4045
4046
4047
4048
4049
4050
4051
4052
4053
4054
4055
4056
4057
4058
4059
4060
4061
4062
4063
4064
4065
4066
4067
4068
4069
4070
4071
4072
4073
4074
4075
4076
4077
4078
4079
4080
4081
4082
4083
4084
4085
4086
4087
4088
4089
4090
4091
4092
4093
4094
4095
4096
4097
4098
4099
4100
4101
4102
4103
4104
4105
4106
4107
4108
4109
4110
4111
4112
4113
4114
4115
4116
4117
4118
4119
4120
4121
4122
4123
4124
4125
4126
4127
4128
4129
4130
4131
4132
4133
4134
4135
4136
4137
4138
4139
4140
4141
4142
4143
/*
*  Copyright (c) 2001 The Regents of the University of Michigan.
*  All rights reserved.
*
*  Kendrick Smith <kmsmith@umich.edu>
*  Andy Adamson <kandros@umich.edu>
*
*  Redistribution and use in source and binary forms, with or without
*  modification, are permitted provided that the following conditions
*  are met:
*
*  1. Redistributions of source code must retain the above copyright
*     notice, this list of conditions and the following disclaimer.
*  2. Redistributions in binary form must reproduce the above copyright
*     notice, this list of conditions and the following disclaimer in the
*     documentation and/or other materials provided with the distribution.
*  3. Neither the name of the University nor the names of its
*     contributors may be used to endorse or promote products derived
*     from this software without specific prior written permission.
*
*  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
*  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
*  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
*  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
*  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
*  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
*  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
*  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
*  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
*  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
*  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/

#include <linux/file.h>
#include <linux/smp_lock.h>
#include <linux/namei.h>
#include <linux/swap.h>
#include <linux/sunrpc/svcauth_gss.h>
#include <linux/sunrpc/clnt.h>
#include "xdr4.h"
#include "vfs.h"

#define NFSDDBG_FACILITY                NFSDDBG_PROC

/* Globals */
static time_t lease_time = 90;     /* default lease time */
static time_t user_lease_time = 90;
static time_t boot_time;
static u32 current_ownerid = 1;
static u32 current_fileid = 1;
static u32 current_delegid = 1;
static u32 nfs4_init;
static stateid_t zerostateid;             /* bits all 0 */
static stateid_t onestateid;              /* bits all 1 */
static u64 current_sessionid = 1;

#define ZERO_STATEID(stateid) (!memcmp((stateid), &zerostateid, sizeof(stateid_t)))
#define ONE_STATEID(stateid)  (!memcmp((stateid), &onestateid, sizeof(stateid_t)))

/* forward declarations */
static struct nfs4_stateid * find_stateid(stateid_t *stid, int flags);
static struct nfs4_delegation * find_delegation_stateid(struct inode *ino, stateid_t *stid);
static char user_recovery_dirname[PATH_MAX] = "/var/lib/nfs/v4recovery";
static void nfs4_set_recdir(char *recdir);

/* Locking: */

/* Currently used for almost all code touching nfsv4 state: */
static DEFINE_MUTEX(client_mutex);

/*
 * Currently used for the del_recall_lru and file hash table.  In an
 * effort to decrease the scope of the client_mutex, this spinlock may
 * eventually cover more:
 */
static DEFINE_SPINLOCK(recall_lock);

static struct kmem_cache *stateowner_slab = NULL;
static struct kmem_cache *file_slab = NULL;
static struct kmem_cache *stateid_slab = NULL;
static struct kmem_cache *deleg_slab = NULL;

void
nfs4_lock_state(void)
{
	mutex_lock(&client_mutex);
}

void
nfs4_unlock_state(void)
{
	mutex_unlock(&client_mutex);
}

static inline u32
opaque_hashval(const void *ptr, int nbytes)
{
	unsigned char *cptr = (unsigned char *) ptr;

	u32 x = 0;
	while (nbytes--) {
		x *= 37;
		x += *cptr++;
	}
	return x;
}

static struct list_head del_recall_lru;

static inline void
put_nfs4_file(struct nfs4_file *fi)
{
	if (atomic_dec_and_lock(&fi->fi_ref, &recall_lock)) {
		list_del(&fi->fi_hash);
		spin_unlock(&recall_lock);
		iput(fi->fi_inode);
		kmem_cache_free(file_slab, fi);
	}
}

static inline void
get_nfs4_file(struct nfs4_file *fi)
{
	atomic_inc(&fi->fi_ref);
}

static int num_delegations;
unsigned int max_delegations;

/*
 * Open owner state (share locks)
 */

/* hash tables for nfs4_stateowner */
#define OWNER_HASH_BITS              8
#define OWNER_HASH_SIZE             (1 << OWNER_HASH_BITS)
#define OWNER_HASH_MASK             (OWNER_HASH_SIZE - 1)

#define ownerid_hashval(id) \
        ((id) & OWNER_HASH_MASK)
#define ownerstr_hashval(clientid, ownername) \
        (((clientid) + opaque_hashval((ownername.data), (ownername.len))) & OWNER_HASH_MASK)

static struct list_head	ownerid_hashtbl[OWNER_HASH_SIZE];
static struct list_head	ownerstr_hashtbl[OWNER_HASH_SIZE];

/* hash table for nfs4_file */
#define FILE_HASH_BITS                   8
#define FILE_HASH_SIZE                  (1 << FILE_HASH_BITS)
#define FILE_HASH_MASK                  (FILE_HASH_SIZE - 1)
/* hash table for (open)nfs4_stateid */
#define STATEID_HASH_BITS              10
#define STATEID_HASH_SIZE              (1 << STATEID_HASH_BITS)
#define STATEID_HASH_MASK              (STATEID_HASH_SIZE - 1)

#define file_hashval(x) \
        hash_ptr(x, FILE_HASH_BITS)
#define stateid_hashval(owner_id, file_id)  \
        (((owner_id) + (file_id)) & STATEID_HASH_MASK)

static struct list_head file_hashtbl[FILE_HASH_SIZE];
static struct list_head stateid_hashtbl[STATEID_HASH_SIZE];

static struct nfs4_delegation *
alloc_init_deleg(struct nfs4_client *clp, struct nfs4_stateid *stp, struct svc_fh *current_fh, u32 type)
{
	struct nfs4_delegation *dp;
	struct nfs4_file *fp = stp->st_file;
	struct nfs4_cb_conn *cb = &stp->st_stateowner->so_client->cl_cb_conn;

	dprintk("NFSD alloc_init_deleg\n");
	if (fp->fi_had_conflict)
		return NULL;
	if (num_delegations > max_delegations)
		return NULL;
	dp = kmem_cache_alloc(deleg_slab, GFP_KERNEL);
	if (dp == NULL)
		return dp;
	num_delegations++;
	INIT_LIST_HEAD(&dp->dl_perfile);
	INIT_LIST_HEAD(&dp->dl_perclnt);
	INIT_LIST_HEAD(&dp->dl_recall_lru);
	dp->dl_client = clp;
	get_nfs4_file(fp);
	dp->dl_file = fp;
	dp->dl_flock = NULL;
	get_file(stp->st_vfs_file);
	dp->dl_vfs_file = stp->st_vfs_file;
	dp->dl_type = type;
	dp->dl_ident = cb->cb_ident;
	dp->dl_stateid.si_boot = get_seconds();
	dp->dl_stateid.si_stateownerid = current_delegid++;
	dp->dl_stateid.si_fileid = 0;
	dp->dl_stateid.si_generation = 0;
	fh_copy_shallow(&dp->dl_fh, &current_fh->fh_handle);
	dp->dl_time = 0;
	atomic_set(&dp->dl_count, 1);
	list_add(&dp->dl_perfile, &fp->fi_delegations);
	list_add(&dp->dl_perclnt, &clp->cl_delegations);
	return dp;
}

void
nfs4_put_delegation(struct nfs4_delegation *dp)
{
	if (atomic_dec_and_test(&dp->dl_count)) {
		dprintk("NFSD: freeing dp %p\n",dp);
		put_nfs4_file(dp->dl_file);
		kmem_cache_free(deleg_slab, dp);
		num_delegations--;
	}
}

/* Remove the associated file_lock first, then remove the delegation.
 * lease_modify() is called to remove the FS_LEASE file_lock from
 * the i_flock list, eventually calling nfsd's lock_manager
 * fl_release_callback.
 */
static void
nfs4_close_delegation(struct nfs4_delegation *dp)
{
	struct file *filp = dp->dl_vfs_file;

	dprintk("NFSD: close_delegation dp %p\n",dp);
	dp->dl_vfs_file = NULL;
	/* The following nfsd_close may not actually close the file,
	 * but we want to remove the lease in any case. */
	if (dp->dl_flock)
		vfs_setlease(filp, F_UNLCK, &dp->dl_flock);
	nfsd_close(filp);
}

/* Called under the state lock. */
static void
unhash_delegation(struct nfs4_delegation *dp)
{
	list_del_init(&dp->dl_perfile);
	list_del_init(&dp->dl_perclnt);
	spin_lock(&recall_lock);
	list_del_init(&dp->dl_recall_lru);
	spin_unlock(&recall_lock);
	nfs4_close_delegation(dp);
	nfs4_put_delegation(dp);
}

/* 
 * SETCLIENTID state 
 */

/* Hash tables for nfs4_clientid state */
#define CLIENT_HASH_BITS                 4
#define CLIENT_HASH_SIZE                (1 << CLIENT_HASH_BITS)
#define CLIENT_HASH_MASK                (CLIENT_HASH_SIZE - 1)

#define clientid_hashval(id) \
	((id) & CLIENT_HASH_MASK)
#define clientstr_hashval(name) \
	(opaque_hashval((name), 8) & CLIENT_HASH_MASK)
/*
 * reclaim_str_hashtbl[] holds known client info from previous reset/reboot
 * used in reboot/reset lease grace period processing
 *
 * conf_id_hashtbl[], and conf_str_hashtbl[] hold confirmed
 * setclientid_confirmed info. 
 *
 * unconf_str_hastbl[] and unconf_id_hashtbl[] hold unconfirmed 
 * setclientid info.
 *
 * client_lru holds client queue ordered by nfs4_client.cl_time
 * for lease renewal.
 *
 * close_lru holds (open) stateowner queue ordered by nfs4_stateowner.so_time
 * for last close replay.
 */
static struct list_head	reclaim_str_hashtbl[CLIENT_HASH_SIZE];
static int reclaim_str_hashtbl_size = 0;
static struct list_head	conf_id_hashtbl[CLIENT_HASH_SIZE];
static struct list_head	conf_str_hashtbl[CLIENT_HASH_SIZE];
static struct list_head	unconf_str_hashtbl[CLIENT_HASH_SIZE];
static struct list_head	unconf_id_hashtbl[CLIENT_HASH_SIZE];
static struct list_head client_lru;
static struct list_head close_lru;

static void unhash_generic_stateid(struct nfs4_stateid *stp)
{
	list_del(&stp->st_hash);
	list_del(&stp->st_perfile);
	list_del(&stp->st_perstateowner);
}

static void free_generic_stateid(struct nfs4_stateid *stp)
{
	put_nfs4_file(stp->st_file);
	kmem_cache_free(stateid_slab, stp);
}

static void release_lock_stateid(struct nfs4_stateid *stp)
{
	unhash_generic_stateid(stp);
	locks_remove_posix(stp->st_vfs_file, (fl_owner_t)stp->st_stateowner);
	free_generic_stateid(stp);
}

static void unhash_lockowner(struct nfs4_stateowner *sop)
{
	struct nfs4_stateid *stp;

	list_del(&sop->so_idhash);
	list_del(&sop->so_strhash);
	list_del(&sop->so_perstateid);
	while (!list_empty(&sop->so_stateids)) {
		stp = list_first_entry(&sop->so_stateids,
				struct nfs4_stateid, st_perstateowner);
		release_lock_stateid(stp);
	}
}

static void release_lockowner(struct nfs4_stateowner *sop)
{
	unhash_lockowner(sop);
	nfs4_put_stateowner(sop);
}

static void
release_stateid_lockowners(struct nfs4_stateid *open_stp)
{
	struct nfs4_stateowner *lock_sop;

	while (!list_empty(&open_stp->st_lockowners)) {
		lock_sop = list_entry(open_stp->st_lockowners.next,
				struct nfs4_stateowner, so_perstateid);
		/* list_del(&open_stp->st_lockowners);  */
		BUG_ON(lock_sop->so_is_open_owner);
		release_lockowner(lock_sop);
	}
}

static void release_open_stateid(struct nfs4_stateid *stp)
{
	unhash_generic_stateid(stp);
	release_stateid_lockowners(stp);
	nfsd_close(stp->st_vfs_file);
	free_generic_stateid(stp);
}

static void unhash_openowner(struct nfs4_stateowner *sop)
{
	struct nfs4_stateid *stp;

	list_del(&sop->so_idhash);
	list_del(&sop->so_strhash);
	list_del(&sop->so_perclient);
	list_del(&sop->so_perstateid); /* XXX: necessary? */
	while (!list_empty(&sop->so_stateids)) {
		stp = list_first_entry(&sop->so_stateids,
				struct nfs4_stateid, st_perstateowner);
		release_open_stateid(stp);
	}
}

static void release_openowner(struct nfs4_stateowner *sop)
{
	unhash_openowner(sop);
	list_del(&sop->so_close_lru);
	nfs4_put_stateowner(sop);
}

static DEFINE_SPINLOCK(sessionid_lock);
#define SESSION_HASH_SIZE	512
static struct list_head sessionid_hashtbl[SESSION_HASH_SIZE];

static inline int
hash_sessionid(struct nfs4_sessionid *sessionid)
{
	struct nfsd4_sessionid *sid = (struct nfsd4_sessionid *)sessionid;

	return sid->sequence % SESSION_HASH_SIZE;
}

static inline void
dump_sessionid(const char *fn, struct nfs4_sessionid *sessionid)
{
	u32 *ptr = (u32 *)(&sessionid->data[0]);
	dprintk("%s: %u:%u:%u:%u\n", fn, ptr[0], ptr[1], ptr[2], ptr[3]);
}

static void
gen_sessionid(struct nfsd4_session *ses)
{
	struct nfs4_client *clp = ses->se_client;
	struct nfsd4_sessionid *sid;

	sid = (struct nfsd4_sessionid *)ses->se_sessionid.data;
	sid->clientid = clp->cl_clientid;
	sid->sequence = current_sessionid++;
	sid->reserved = 0;
}

/*
 * The protocol defines ca_maxresponssize_cached to include the size of
 * the rpc header, but all we need to cache is the data starting after
 * the end of the initial SEQUENCE operation--the rest we regenerate
 * each time.  Therefore we can advertise a ca_maxresponssize_cached
 * value that is the number of bytes in our cache plus a few additional
 * bytes.  In order to stay on the safe side, and not promise more than
 * we can cache, those additional bytes must be the minimum possible: 24
 * bytes of rpc header (xid through accept state, with AUTH_NULL
 * verifier), 12 for the compound header (with zero-length tag), and 44
 * for the SEQUENCE op response:
 */
#define NFSD_MIN_HDR_SEQ_SZ  (24 + 12 + 44)

/*
 * Give the client the number of ca_maxresponsesize_cached slots it
 * requests, of size bounded by NFSD_SLOT_CACHE_SIZE,
 * NFSD_MAX_MEM_PER_SESSION, and nfsd_drc_max_mem. Do not allow more
 * than NFSD_MAX_SLOTS_PER_SESSION.
 *
 * If we run out of reserved DRC memory we should (up to a point)
 * re-negotiate active sessions and reduce their slot usage to make
 * rooom for new connections. For now we just fail the create session.
 */
static int set_forechannel_drc_size(struct nfsd4_channel_attrs *fchan)
{
	int mem, size = fchan->maxresp_cached;

	if (fchan->maxreqs < 1)
		return nfserr_inval;

	if (size < NFSD_MIN_HDR_SEQ_SZ)
		size = NFSD_MIN_HDR_SEQ_SZ;
	size -= NFSD_MIN_HDR_SEQ_SZ;
	if (size > NFSD_SLOT_CACHE_SIZE)
		size = NFSD_SLOT_CACHE_SIZE;

	/* bound the maxreqs by NFSD_MAX_MEM_PER_SESSION */
	mem = fchan->maxreqs * size;
	if (mem > NFSD_MAX_MEM_PER_SESSION) {
		fchan->maxreqs = NFSD_MAX_MEM_PER_SESSION / size;
		if (fchan->maxreqs > NFSD_MAX_SLOTS_PER_SESSION)
			fchan->maxreqs = NFSD_MAX_SLOTS_PER_SESSION;
		mem = fchan->maxreqs * size;
	}

	spin_lock(&nfsd_drc_lock);
	/* bound the total session drc memory ussage */
	if (mem + nfsd_drc_mem_used > nfsd_drc_max_mem) {
		fchan->maxreqs = (nfsd_drc_max_mem - nfsd_drc_mem_used) / size;
		mem = fchan->maxreqs * size;
	}
	nfsd_drc_mem_used += mem;
	spin_unlock(&nfsd_drc_lock);

	if (fchan->maxreqs == 0)
		return nfserr_serverfault;

	fchan->maxresp_cached = size + NFSD_MIN_HDR_SEQ_SZ;
	return 0;
}

/*
 * fchan holds the client values on input, and the server values on output
 * sv_max_mesg is the maximum payload plus one page for overhead.
 */
static int init_forechannel_attrs(struct svc_rqst *rqstp,
				  struct nfsd4_channel_attrs *session_fchan,
				  struct nfsd4_channel_attrs *fchan)
{
	int status = 0;
	__u32   maxcount = nfsd_serv->sv_max_mesg;

	/* headerpadsz set to zero in encode routine */

	/* Use the client's max request and max response size if possible */
	if (fchan->maxreq_sz > maxcount)
		fchan->maxreq_sz = maxcount;
	session_fchan->maxreq_sz = fchan->maxreq_sz;

	if (fchan->maxresp_sz > maxcount)
		fchan->maxresp_sz = maxcount;
	session_fchan->maxresp_sz = fchan->maxresp_sz;

	/* Use the client's maxops if possible */
	if (fchan->maxops > NFSD_MAX_OPS_PER_COMPOUND)
		fchan->maxops = NFSD_MAX_OPS_PER_COMPOUND;
	session_fchan->maxops = fchan->maxops;

	/* FIXME: Error means no more DRC pages so the server should
	 * recover pages from existing sessions. For now fail session
	 * creation.
	 */
	status = set_forechannel_drc_size(fchan);

	session_fchan->maxresp_cached = fchan->maxresp_cached;
	session_fchan->maxreqs = fchan->maxreqs;

	dprintk("%s status %d\n", __func__, status);
	return status;
}

static void
free_session_slots(struct nfsd4_session *ses)
{
	int i;

	for (i = 0; i < ses->se_fchannel.maxreqs; i++)
		kfree(ses->se_slots[i]);
}

/*
 * We don't actually need to cache the rpc and session headers, so we
 * can allocate a little less for each slot:
 */
static inline int slot_bytes(struct nfsd4_channel_attrs *ca)
{
	return ca->maxresp_cached - NFSD_MIN_HDR_SEQ_SZ;
}

static int
alloc_init_session(struct svc_rqst *rqstp, struct nfs4_client *clp,
		   struct nfsd4_create_session *cses)
{
	struct nfsd4_session *new, tmp;
	struct nfsd4_slot *sp;
	int idx, slotsize, cachesize, i;
	int status;

	memset(&tmp, 0, sizeof(tmp));

	/* FIXME: For now, we just accept the client back channel attributes. */
	tmp.se_bchannel = cses->back_channel;
	status = init_forechannel_attrs(rqstp, &tmp.se_fchannel,
					&cses->fore_channel);
	if (status)
		goto out;

	BUILD_BUG_ON(NFSD_MAX_SLOTS_PER_SESSION * sizeof(struct nfsd4_slot)
		     + sizeof(struct nfsd4_session) > PAGE_SIZE);

	status = nfserr_serverfault;
	/* allocate struct nfsd4_session and slot table pointers in one piece */
	slotsize = tmp.se_fchannel.maxreqs * sizeof(struct nfsd4_slot *);
	new = kzalloc(sizeof(*new) + slotsize, GFP_KERNEL);
	if (!new)
		goto out;

	memcpy(new, &tmp, sizeof(*new));

	/* allocate each struct nfsd4_slot and data cache in one piece */
	cachesize = slot_bytes(&new->se_fchannel);
	for (i = 0; i < new->se_fchannel.maxreqs; i++) {
		sp = kzalloc(sizeof(*sp) + cachesize, GFP_KERNEL);
		if (!sp)
			goto out_free;
		new->se_slots[i] = sp;
	}

	new->se_client = clp;
	gen_sessionid(new);
	idx = hash_sessionid(&new->se_sessionid);
	memcpy(clp->cl_sessionid.data, new->se_sessionid.data,
	       NFS4_MAX_SESSIONID_LEN);

	new->se_flags = cses->flags;
	kref_init(&new->se_ref);
	spin_lock(&sessionid_lock);
	list_add(&new->se_hash, &sessionid_hashtbl[idx]);
	list_add(&new->se_perclnt, &clp->cl_sessions);
	spin_unlock(&sessionid_lock);

	status = nfs_ok;
out:
	return status;
out_free:
	free_session_slots(new);
	kfree(new);
	goto out;
}

/* caller must hold sessionid_lock */
static struct nfsd4_session *
find_in_sessionid_hashtbl(struct nfs4_sessionid *sessionid)
{
	struct nfsd4_session *elem;
	int idx;

	dump_sessionid(__func__, sessionid);
	idx = hash_sessionid(sessionid);
	dprintk("%s: idx is %d\n", __func__, idx);
	/* Search in the appropriate list */
	list_for_each_entry(elem, &sessionid_hashtbl[idx], se_hash) {
		dump_sessionid("list traversal", &elem->se_sessionid);
		if (!memcmp(elem->se_sessionid.data, sessionid->data,
			    NFS4_MAX_SESSIONID_LEN)) {
			return elem;
		}
	}

	dprintk("%s: session not found\n", __func__);
	return NULL;
}

/* caller must hold sessionid_lock */
static void
unhash_session(struct nfsd4_session *ses)
{
	list_del(&ses->se_hash);
	list_del(&ses->se_perclnt);
}

static void
release_session(struct nfsd4_session *ses)
{
	spin_lock(&sessionid_lock);
	unhash_session(ses);
	spin_unlock(&sessionid_lock);
	nfsd4_put_session(ses);
}

void
free_session(struct kref *kref)
{
	struct nfsd4_session *ses;
	int mem;

	ses = container_of(kref, struct nfsd4_session, se_ref);
	spin_lock(&nfsd_drc_lock);
	mem = ses->se_fchannel.maxreqs * slot_bytes(&ses->se_fchannel);
	nfsd_drc_mem_used -= mem;
	spin_unlock(&nfsd_drc_lock);
	free_session_slots(ses);
	kfree(ses);
}

static inline void
renew_client(struct nfs4_client *clp)
{
	/*
	* Move client to the end to the LRU list.
	*/
	dprintk("renewing client (clientid %08x/%08x)\n", 
			clp->cl_clientid.cl_boot, 
			clp->cl_clientid.cl_id);
	list_move_tail(&clp->cl_lru, &client_lru);
	clp->cl_time = get_seconds();
}

/* SETCLIENTID and SETCLIENTID_CONFIRM Helper functions */
static int
STALE_CLIENTID(clientid_t *clid)
{
	if (clid->cl_boot == boot_time)
		return 0;
	dprintk("NFSD stale clientid (%08x/%08x) boot_time %08lx\n",
		clid->cl_boot, clid->cl_id, boot_time);
	return 1;
}

/* 
 * XXX Should we use a slab cache ?
 * This type of memory management is somewhat inefficient, but we use it
 * anyway since SETCLIENTID is not a common operation.
 */
static struct nfs4_client *alloc_client(struct xdr_netobj name)
{
	struct nfs4_client *clp;

	clp = kzalloc(sizeof(struct nfs4_client), GFP_KERNEL);
	if (clp == NULL)
		return NULL;
	clp->cl_name.data = kmalloc(name.len, GFP_KERNEL);
	if (clp->cl_name.data == NULL) {
		kfree(clp);
		return NULL;
	}
	memcpy(clp->cl_name.data, name.data, name.len);
	clp->cl_name.len = name.len;
	return clp;
}

static void
shutdown_callback_client(struct nfs4_client *clp)
{
	struct rpc_clnt *clnt = clp->cl_cb_conn.cb_client;

	if (clnt) {
		/*
		 * Callback threads take a reference on the client, so there
		 * should be no outstanding callbacks at this point.
		 */
		clp->cl_cb_conn.cb_client = NULL;
		rpc_shutdown_client(clnt);
	}
}

static inline void
free_client(struct nfs4_client *clp)
{
	shutdown_callback_client(clp);
	if (clp->cl_cb_xprt)
		svc_xprt_put(clp->cl_cb_xprt);
	if (clp->cl_cred.cr_group_info)
		put_group_info(clp->cl_cred.cr_group_info);
	kfree(clp->cl_principal);
	kfree(clp->cl_name.data);
	kfree(clp);
}

void
put_nfs4_client(struct nfs4_client *clp)
{
	if (atomic_dec_and_test(&clp->cl_count))
		free_client(clp);
}

static void
expire_client(struct nfs4_client *clp)
{
	struct nfs4_stateowner *sop;
	struct nfs4_delegation *dp;
	struct list_head reaplist;

	dprintk("NFSD: expire_client cl_count %d\n",
	                    atomic_read(&clp->cl_count));

	INIT_LIST_HEAD(&reaplist);
	spin_lock(&recall_lock);
	while (!list_empty(&clp->cl_delegations)) {
		dp = list_entry(clp->cl_delegations.next, struct nfs4_delegation, dl_perclnt);
		dprintk("NFSD: expire client. dp %p, fp %p\n", dp,
				dp->dl_flock);
		list_del_init(&dp->dl_perclnt);
		list_move(&dp->dl_recall_lru, &reaplist);
	}
	spin_unlock(&recall_lock);
	while (!list_empty(&reaplist)) {
		dp = list_entry(reaplist.next, struct nfs4_delegation, dl_recall_lru);
		list_del_init(&dp->dl_recall_lru);
		unhash_delegation(dp);
	}
	list_del(&clp->cl_idhash);
	list_del(&clp->cl_strhash);
	list_del(&clp->cl_lru);
	while (!list_empty(&clp->cl_openowners)) {
		sop = list_entry(clp->cl_openowners.next, struct nfs4_stateowner, so_perclient);
		release_openowner(sop);
	}
	while (!list_empty(&clp->cl_sessions)) {
		struct nfsd4_session  *ses;
		ses = list_entry(clp->cl_sessions.next, struct nfsd4_session,
				 se_perclnt);
		release_session(ses);
	}
	put_nfs4_client(clp);
}

static void copy_verf(struct nfs4_client *target, nfs4_verifier *source)
{
	memcpy(target->cl_verifier.data, source->data,
			sizeof(target->cl_verifier.data));
}

static void copy_clid(struct nfs4_client *target, struct nfs4_client *source)
{
	target->cl_clientid.cl_boot = source->cl_clientid.cl_boot; 
	target->cl_clientid.cl_id = source->cl_clientid.cl_id; 
}

static void copy_cred(struct svc_cred *target, struct svc_cred *source)
{
	target->cr_uid = source->cr_uid;
	target->cr_gid = source->cr_gid;
	target->cr_group_info = source->cr_group_info;
	get_group_info(target->cr_group_info);
}

static int same_name(const char *n1, const char *n2)
{
	return 0 == memcmp(n1, n2, HEXDIR_LEN);
}

static int
same_verf(nfs4_verifier *v1, nfs4_verifier *v2)
{
	return 0 == memcmp(v1->data, v2->data, sizeof(v1->data));
}

static int
same_clid(clientid_t *cl1, clientid_t *cl2)
{
	return (cl1->cl_boot == cl2->cl_boot) && (cl1->cl_id == cl2->cl_id);
}

/* XXX what about NGROUP */
static int
same_creds(struct svc_cred *cr1, struct svc_cred *cr2)
{
	return cr1->cr_uid == cr2->cr_uid;
}

static void gen_clid(struct nfs4_client *clp)
{
	static u32 current_clientid = 1;

	clp->cl_clientid.cl_boot = boot_time;
	clp->cl_clientid.cl_id = current_clientid++; 
}

static void gen_confirm(struct nfs4_client *clp)
{
	static u32 i;
	u32 *p;

	p = (u32 *)clp->cl_confirm.data;
	*p++ = get_seconds();
	*p++ = i++;
}

static struct nfs4_client *create_client(struct xdr_netobj name, char *recdir,
		struct svc_rqst *rqstp, nfs4_verifier *verf)
{
	struct nfs4_client *clp;
	struct sockaddr *sa = svc_addr(rqstp);
	char *princ;

	clp = alloc_client(name);
	if (clp == NULL)
		return NULL;

	princ = svc_gss_principal(rqstp);
	if (princ) {
		clp->cl_principal = kstrdup(princ, GFP_KERNEL);
		if (clp->cl_principal == NULL) {
			free_client(clp);
			return NULL;
		}
	}

	memcpy(clp->cl_recdir, recdir, HEXDIR_LEN);
	atomic_set(&clp->cl_count, 1);
	atomic_set(&clp->cl_cb_conn.cb_set, 0);
	INIT_LIST_HEAD(&clp->cl_idhash);
	INIT_LIST_HEAD(&clp->cl_strhash);
	INIT_LIST_HEAD(&clp->cl_openowners);
	INIT_LIST_HEAD(&clp->cl_delegations);
	INIT_LIST_HEAD(&clp->cl_sessions);
	INIT_LIST_HEAD(&clp->cl_lru);
	clear_bit(0, &clp->cl_cb_slot_busy);
	rpc_init_wait_queue(&clp->cl_cb_waitq, "Backchannel slot table");
	copy_verf(clp, verf);
	rpc_copy_addr((struct sockaddr *) &clp->cl_addr, sa);
	clp->cl_flavor = rqstp->rq_flavor;
	copy_cred(&clp->cl_cred, &rqstp->rq_cred);
	gen_confirm(clp);

	return clp;
}

static int check_name(struct xdr_netobj name)
{
	if (name.len == 0) 
		return 0;
	if (name.len > NFS4_OPAQUE_LIMIT) {
		dprintk("NFSD: check_name: name too long(%d)!\n", name.len);
		return 0;
	}
	return 1;
}

static void
add_to_unconfirmed(struct nfs4_client *clp, unsigned int strhashval)
{
	unsigned int idhashval;

	list_add(&clp->cl_strhash, &unconf_str_hashtbl[strhashval]);
	idhashval = clientid_hashval(clp->cl_clientid.cl_id);
	list_add(&clp->cl_idhash, &unconf_id_hashtbl[idhashval]);
	list_add_tail(&clp->cl_lru, &client_lru);
	clp->cl_time = get_seconds();
}

static void
move_to_confirmed(struct nfs4_client *clp)
{
	unsigned int idhashval = clientid_hashval(clp->cl_clientid.cl_id);
	unsigned int strhashval;

	dprintk("NFSD: move_to_confirm nfs4_client %p\n", clp);
	list_del_init(&clp->cl_strhash);
	list_move(&clp->cl_idhash, &conf_id_hashtbl[idhashval]);
	strhashval = clientstr_hashval(clp->cl_recdir);
	list_add(&clp->cl_strhash, &conf_str_hashtbl[strhashval]);
	renew_client(clp);
}

static struct nfs4_client *
find_confirmed_client(clientid_t *clid)
{
	struct nfs4_client *clp;
	unsigned int idhashval = clientid_hashval(clid->cl_id);

	list_for_each_entry(clp, &conf_id_hashtbl[idhashval], cl_idhash) {
		if (same_clid(&clp->cl_clientid, clid))
			return clp;
	}
	return NULL;
}

static struct nfs4_client *
find_unconfirmed_client(clientid_t *clid)
{
	struct nfs4_client *clp;
	unsigned int idhashval = clientid_hashval(clid->cl_id);

	list_for_each_entry(clp, &unconf_id_hashtbl[idhashval], cl_idhash) {
		if (same_clid(&clp->cl_clientid, clid))
			return clp;
	}
	return NULL;
}

/*
 * Return 1 iff clp's clientid establishment method matches the use_exchange_id
 * parameter. Matching is based on the fact the at least one of the
 * EXCHGID4_FLAG_USE_{NON_PNFS,PNFS_MDS,PNFS_DS} flags must be set for v4.1
 *
 * FIXME: we need to unify the clientid namespaces for nfsv4.x
 * and correctly deal with client upgrade/downgrade in EXCHANGE_ID
 * and SET_CLIENTID{,_CONFIRM}
 */
static inline int
match_clientid_establishment(struct nfs4_client *clp, bool use_exchange_id)
{
	bool has_exchange_flags = (clp->cl_exchange_flags != 0);
	return use_exchange_id == has_exchange_flags;
}

static struct nfs4_client *
find_confirmed_client_by_str(const char *dname, unsigned int hashval,
			     bool use_exchange_id)
{
	struct nfs4_client *clp;

	list_for_each_entry(clp, &conf_str_hashtbl[hashval], cl_strhash) {
		if (same_name(clp->cl_recdir, dname) &&
		    match_clientid_establishment(clp, use_exchange_id))
			return clp;
	}
	return NULL;
}

static struct nfs4_client *
find_unconfirmed_client_by_str(const char *dname, unsigned int hashval,
			       bool use_exchange_id)
{
	struct nfs4_client *clp;

	list_for_each_entry(clp, &unconf_str_hashtbl[hashval], cl_strhash) {
		if (same_name(clp->cl_recdir, dname) &&
		    match_clientid_establishment(clp, use_exchange_id))
			return clp;
	}
	return NULL;
}

static void
gen_callback(struct nfs4_client *clp, struct nfsd4_setclientid *se, u32 scopeid)
{
	struct nfs4_cb_conn *cb = &clp->cl_cb_conn;
	unsigned short expected_family;

	/* Currently, we only support tcp and tcp6 for the callback channel */
	if (se->se_callback_netid_len == 3 &&
	    !memcmp(se->se_callback_netid_val, "tcp", 3))
		expected_family = AF_INET;
	else if (se->se_callback_netid_len == 4 &&
		 !memcmp(se->se_callback_netid_val, "tcp6", 4))
		expected_family = AF_INET6;
	else
		goto out_err;

	cb->cb_addrlen = rpc_uaddr2sockaddr(se->se_callback_addr_val,
					    se->se_callback_addr_len,
					    (struct sockaddr *) &cb->cb_addr,
					    sizeof(cb->cb_addr));

	if (!cb->cb_addrlen || cb->cb_addr.ss_family != expected_family)
		goto out_err;

	if (cb->cb_addr.ss_family == AF_INET6)
		((struct sockaddr_in6 *) &cb->cb_addr)->sin6_scope_id = scopeid;

	cb->cb_minorversion = 0;
	cb->cb_prog = se->se_callback_prog;
	cb->cb_ident = se->se_callback_ident;
	return;
out_err:
	cb->cb_addr.ss_family = AF_UNSPEC;
	cb->cb_addrlen = 0;
	dprintk(KERN_INFO "NFSD: this client (clientid %08x/%08x) "
		"will not receive delegations\n",
		clp->cl_clientid.cl_boot, clp->cl_clientid.cl_id);

	return;
}

/*
 * Cache a reply. nfsd4_check_drc_limit() has bounded the cache size.
 */
void
nfsd4_store_cache_entry(struct nfsd4_compoundres *resp)
{
	struct nfsd4_slot *slot = resp->cstate.slot;
	unsigned int base;

	dprintk("--> %s slot %p\n", __func__, slot);

	slot->sl_opcnt = resp->opcnt;
	slot->sl_status = resp->cstate.status;

	if (nfsd4_not_cached(resp)) {
		slot->sl_datalen = 0;
		return;
	}
	slot->sl_datalen = (char *)resp->p - (char *)resp->cstate.datap;
	base = (char *)resp->cstate.datap -
					(char *)resp->xbuf->head[0].iov_base;
	if (read_bytes_from_xdr_buf(resp->xbuf, base, slot->sl_data,
				    slot->sl_datalen))
		WARN("%s: sessions DRC could not cache compound\n", __func__);
	return;
}

/*
 * Encode the replay sequence operation from the slot values.
 * If cachethis is FALSE encode the uncached rep error on the next
 * operation which sets resp->p and increments resp->opcnt for
 * nfs4svc_encode_compoundres.
 *
 */
static __be32
nfsd4_enc_sequence_replay(struct nfsd4_compoundargs *args,
			  struct nfsd4_compoundres *resp)
{
	struct nfsd4_op *op;
	struct nfsd4_slot *slot = resp->cstate.slot;

	dprintk("--> %s resp->opcnt %d cachethis %u \n", __func__,
		resp->opcnt, resp->cstate.slot->sl_cachethis);

	/* Encode the replayed sequence operation */
	op = &args->ops[resp->opcnt - 1];
	nfsd4_encode_operation(resp, op);

	/* Return nfserr_retry_uncached_rep in next operation. */
	if (args->opcnt > 1 && slot->sl_cachethis == 0) {
		op = &args->ops[resp->opcnt++];
		op->status = nfserr_retry_uncached_rep;
		nfsd4_encode_operation(resp, op);
	}
	return op->status;
}

/*
 * The sequence operation is not cached because we can use the slot and
 * session values.
 */
__be32
nfsd4_replay_cache_entry(struct nfsd4_compoundres *resp,
			 struct nfsd4_sequence *seq)
{
	struct nfsd4_slot *slot = resp->cstate.slot;
	__be32 status;

	dprintk("--> %s slot %p\n", __func__, slot);

	/* Either returns 0 or nfserr_retry_uncached */
	status = nfsd4_enc_sequence_replay(resp->rqstp->rq_argp, resp);
	if (status == nfserr_retry_uncached_rep)
		return status;

	/* The sequence operation has been encoded, cstate->datap set. */
	memcpy(resp->cstate.datap, slot->sl_data, slot->sl_datalen);

	resp->opcnt = slot->sl_opcnt;
	resp->p = resp->cstate.datap + XDR_QUADLEN(slot->sl_datalen);
	status = slot->sl_status;

	return status;
}

/*
 * Set the exchange_id flags returned by the server.
 */
static void
nfsd4_set_ex_flags(struct nfs4_client *new, struct nfsd4_exchange_id *clid)
{
	/* pNFS is not supported */
	new->cl_exchange_flags |= EXCHGID4_FLAG_USE_NON_PNFS;

	/* Referrals are supported, Migration is not. */
	new->cl_exchange_flags |= EXCHGID4_FLAG_SUPP_MOVED_REFER;

	/* set the wire flags to return to client. */
	clid->flags = new->cl_exchange_flags;
}

__be32
nfsd4_exchange_id(struct svc_rqst *rqstp,
		  struct nfsd4_compound_state *cstate,
		  struct nfsd4_exchange_id *exid)
{
	struct nfs4_client *unconf, *conf, *new;
	int status;
	unsigned int		strhashval;
	char			dname[HEXDIR_LEN];
	char			addr_str[INET6_ADDRSTRLEN];
	nfs4_verifier		verf = exid->verifier;
	struct sockaddr		*sa = svc_addr(rqstp);

	rpc_ntop(sa, addr_str, sizeof(addr_str));
	dprintk("%s rqstp=%p exid=%p clname.len=%u clname.data=%p "
		"ip_addr=%s flags %x, spa_how %d\n",
		__func__, rqstp, exid, exid->clname.len, exid->clname.data,
		addr_str, exid->flags, exid->spa_how);

	if (!check_name(exid->clname) || (exid->flags & ~EXCHGID4_FLAG_MASK_A))
		return nfserr_inval;

	/* Currently only support SP4_NONE */
	switch (exid->spa_how) {
	case SP4_NONE:
		break;
	case SP4_SSV:
		return nfserr_encr_alg_unsupp;
	default:
		BUG();				/* checked by xdr code */
	case SP4_MACH_CRED:
		return nfserr_serverfault;	/* no excuse :-/ */
	}

	status = nfs4_make_rec_clidname(dname, &exid->clname);

	if (status)
		goto error;

	strhashval = clientstr_hashval(dname);

	nfs4_lock_state();
	status = nfs_ok;

	conf = find_confirmed_client_by_str(dname, strhashval, true);
	if (conf) {
		if (!same_verf(&verf, &conf->cl_verifier)) {
			/* 18.35.4 case 8 */
			if (exid->flags & EXCHGID4_FLAG_UPD_CONFIRMED_REC_A) {
				status = nfserr_not_same;
				goto out;
			}
			/* Client reboot: destroy old state */
			expire_client(conf);
			goto out_new;
		}
		if (!same_creds(&conf->cl_cred, &rqstp->rq_cred)) {
			/* 18.35.4 case 9 */
			if (exid->flags & EXCHGID4_FLAG_UPD_CONFIRMED_REC_A) {
				status = nfserr_perm;
				goto out;
			}
			expire_client(conf);
			goto out_new;
		}
		/*
		 * Set bit when the owner id and verifier map to an already
		 * confirmed client id (18.35.3).
		 */
		exid->flags |= EXCHGID4_FLAG_CONFIRMED_R;

		/*
		 * Falling into 18.35.4 case 2, possible router replay.
		 * Leave confirmed record intact and return same result.
		 */
		copy_verf(conf, &verf);
		new = conf;
		goto out_copy;
	}

	/* 18.35.4 case 7 */
	if (exid->flags & EXCHGID4_FLAG_UPD_CONFIRMED_REC_A) {
		status = nfserr_noent;
		goto out;
	}

	unconf  = find_unconfirmed_client_by_str(dname, strhashval, true);
	if (unconf) {
		/*
		 * Possible retry or client restart.  Per 18.35.4 case 4,
		 * a new unconfirmed record should be generated regardless
		 * of whether any properties have changed.
		 */
		expire_client(unconf);
	}

out_new:
	/* Normal case */
	new = create_client(exid->clname, dname, rqstp, &verf);
	if (new == NULL) {
		status = nfserr_serverfault;
		goto out;
	}

	gen_clid(new);
	add_to_unconfirmed(new, strhashval);
out_copy:
	exid->clientid.cl_boot = new->cl_clientid.cl_boot;
	exid->clientid.cl_id = new->cl_clientid.cl_id;

	exid->seqid = 1;
	nfsd4_set_ex_flags(new, exid);

	dprintk("nfsd4_exchange_id seqid %d flags %x\n",
		new->cl_cs_slot.sl_seqid, new->cl_exchange_flags);
	status = nfs_ok;

out:
	nfs4_unlock_state();
error:
	dprintk("nfsd4_exchange_id returns %d\n", ntohl(status));
	return status;
}

static int
check_slot_seqid(u32 seqid, u32 slot_seqid, int slot_inuse)
{
	dprintk("%s enter. seqid %d slot_seqid %d\n", __func__, seqid,
		slot_seqid);

	/* The slot is in use, and no response has been sent. */
	if (slot_inuse) {
		if (seqid == slot_seqid)
			return nfserr_jukebox;
		else
			return nfserr_seq_misordered;
	}
	/* Normal */
	if (likely(seqid == slot_seqid + 1))
		return nfs_ok;
	/* Replay */
	if (seqid == slot_seqid)
		return nfserr_replay_cache;
	/* Wraparound */
	if (seqid == 1 && (slot_seqid + 1) == 0)
		return nfs_ok;
	/* Misordered replay or misordered new request */
	return nfserr_seq_misordered;
}

/*
 * Cache the create session result into the create session single DRC
 * slot cache by saving the xdr structure. sl_seqid has been set.
 * Do this for solo or embedded create session operations.
 */
static void
nfsd4_cache_create_session(struct nfsd4_create_session *cr_ses,
			   struct nfsd4_clid_slot *slot, int nfserr)
{
	slot->sl_status = nfserr;
	memcpy(&slot->sl_cr_ses, cr_ses, sizeof(*cr_ses));
}

static __be32
nfsd4_replay_create_session(struct nfsd4_create_session *cr_ses,
			    struct nfsd4_clid_slot *slot)
{
	memcpy(cr_ses, &slot->sl_cr_ses, sizeof(*cr_ses));
	return slot->sl_status;
}

__be32
nfsd4_create_session(struct svc_rqst *rqstp,
		     struct nfsd4_compound_state *cstate,
		     struct nfsd4_create_session *cr_ses)
{
	struct sockaddr *sa = svc_addr(rqstp);
	struct nfs4_client *conf, *unconf;
	struct nfsd4_clid_slot *cs_slot = NULL;
	int status = 0;

	nfs4_lock_state();
	unconf = find_unconfirmed_client(&cr_ses->clientid);
	conf = find_confirmed_client(&cr_ses->clientid);

	if (conf) {
		cs_slot = &conf->cl_cs_slot;
		status = check_slot_seqid(cr_ses->seqid, cs_slot->sl_seqid, 0);
		if (status == nfserr_replay_cache) {
			dprintk("Got a create_session replay! seqid= %d\n",
				cs_slot->sl_seqid);
			/* Return the cached reply status */
			status = nfsd4_replay_create_session(cr_ses, cs_slot);
			goto out;
		} else if (cr_ses->seqid != cs_slot->sl_seqid + 1) {
			status = nfserr_seq_misordered;
			dprintk("Sequence misordered!\n");
			dprintk("Expected seqid= %d but got seqid= %d\n",
				cs_slot->sl_seqid, cr_ses->seqid);
			goto out;
		}
		cs_slot->sl_seqid++;
	} else if (unconf) {
		if (!same_creds(&unconf->cl_cred, &rqstp->rq_cred) ||
		    !rpc_cmp_addr(sa, (struct sockaddr *) &unconf->cl_addr)) {
			status = nfserr_clid_inuse;
			goto out;
		}

		cs_slot = &unconf->cl_cs_slot;
		status = check_slot_seqid(cr_ses->seqid, cs_slot->sl_seqid, 0);
		if (status) {
			/* an unconfirmed replay returns misordered */
			status = nfserr_seq_misordered;
			goto out_cache;
		}

		cs_slot->sl_seqid++; /* from 0 to 1 */
		move_to_confirmed(unconf);

		/*
		 * We do not support RDMA or persistent sessions
		 */
		cr_ses->flags &= ~SESSION4_PERSIST;
		cr_ses->flags &= ~SESSION4_RDMA;

		if (cr_ses->flags & SESSION4_BACK_CHAN) {
			unconf->cl_cb_xprt = rqstp->rq_xprt;
			svc_xprt_get(unconf->cl_cb_xprt);
			rpc_copy_addr(
				(struct sockaddr *)&unconf->cl_cb_conn.cb_addr,
				sa);
			unconf->cl_cb_conn.cb_addrlen = svc_addr_len(sa);
			unconf->cl_cb_conn.cb_minorversion =
				cstate->minorversion;
			unconf->cl_cb_conn.cb_prog = cr_ses->callback_prog;
			unconf->cl_cb_seq_nr = 1;
			nfsd4_probe_callback(unconf);
		}
		conf = unconf;
	} else {
		status = nfserr_stale_clientid;
		goto out;
	}

	status = alloc_init_session(rqstp, conf, cr_ses);
	if (status)
		goto out;

	memcpy(cr_ses->sessionid.data, conf->cl_sessionid.data,
	       NFS4_MAX_SESSIONID_LEN);
	cr_ses->seqid = cs_slot->sl_seqid;

out_cache:
	/* cache solo and embedded create sessions under the state lock */
	nfsd4_cache_create_session(cr_ses, cs_slot, status);
out:
	nfs4_unlock_state();
	dprintk("%s returns %d\n", __func__, ntohl(status));
	return status;
}

__be32
nfsd4_destroy_session(struct svc_rqst *r,
		      struct nfsd4_compound_state *cstate,
		      struct nfsd4_destroy_session *sessionid)
{
	struct nfsd4_session *ses;
	u32 status = nfserr_badsession;

	/* Notes:
	 * - The confirmed nfs4_client->cl_sessionid holds destroyed sessinid
	 * - Should we return nfserr_back_chan_busy if waiting for
	 *   callbacks on to-be-destroyed session?
	 * - Do we need to clear any callback info from previous session?
	 */

	dump_sessionid(__func__, &sessionid->sessionid);
	spin_lock(&sessionid_lock);
	ses = find_in_sessionid_hashtbl(&sessionid->sessionid);
	if (!ses) {
		spin_unlock(&sessionid_lock);
		goto out;
	}

	unhash_session(ses);
	spin_unlock(&sessionid_lock);

	/* wait for callbacks */
	shutdown_callback_client(ses->se_client);
	nfsd4_put_session(ses);
	status = nfs_ok;
out:
	dprintk("%s returns %d\n", __func__, ntohl(status));
	return status;
}

__be32
nfsd4_sequence(struct svc_rqst *rqstp,
	       struct nfsd4_compound_state *cstate,
	       struct nfsd4_sequence *seq)
{
	struct nfsd4_compoundres *resp = rqstp->rq_resp;
	struct nfsd4_session *session;
	struct nfsd4_slot *slot;
	int status;

	if (resp->opcnt != 1)
		return nfserr_sequence_pos;

	spin_lock(&sessionid_lock);
	status = nfserr_badsession;
	session = find_in_sessionid_hashtbl(&seq->sessionid);
	if (!session)
		goto out;

	status = nfserr_badslot;
	if (seq->slotid >= session->se_fchannel.maxreqs)
		goto out;

	slot = session->se_slots[seq->slotid];
	dprintk("%s: slotid %d\n", __func__, seq->slotid);

	/* We do not negotiate the number of slots yet, so set the
	 * maxslots to the session maxreqs which is used to encode
	 * sr_highest_slotid and the sr_target_slot id to maxslots */
	seq->maxslots = session->se_fchannel.maxreqs;

	status = check_slot_seqid(seq->seqid, slot->sl_seqid, slot->sl_inuse);
	if (status == nfserr_replay_cache) {
		cstate->slot = slot;
		cstate->session = session;
		/* Return the cached reply status and set cstate->status
		 * for nfsd4_proc_compound processing */
		status = nfsd4_replay_cache_entry(resp, seq);
		cstate->status = nfserr_replay_cache;
		goto out;
	}
	if (status)
		goto out;

	/* Success! bump slot seqid */
	slot->sl_inuse = true;
	slot->sl_seqid = seq->seqid;
	slot->sl_cachethis = seq->cachethis;

	cstate->slot = slot;
	cstate->session = session;

	/* Hold a session reference until done processing the compound:
	 * nfsd4_put_session called only if the cstate slot is set.
	 */
	nfsd4_get_session(session);
out:
	spin_unlock(&sessionid_lock);
	/* Renew the clientid on success and on replay */
	if (cstate->session) {
		nfs4_lock_state();
		renew_client(session->se_client);
		nfs4_unlock_state();
	}
	dprintk("%s: return %d\n", __func__, ntohl(status));
	return status;
}

__be32
nfsd4_setclientid(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
		  struct nfsd4_setclientid *setclid)
{
	struct sockaddr		*sa = svc_addr(rqstp);
	struct xdr_netobj 	clname = { 
		.len = setclid->se_namelen,
		.data = setclid->se_name,
	};
	nfs4_verifier		clverifier = setclid->se_verf;
	unsigned int 		strhashval;
	struct nfs4_client	*conf, *unconf, *new;
	__be32 			status;
	char                    dname[HEXDIR_LEN];
	
	if (!check_name(clname))
		return nfserr_inval;

	status = nfs4_make_rec_clidname(dname, &clname);
	if (status)
		return status;

	/* 
	 * XXX The Duplicate Request Cache (DRC) has been checked (??)
	 * We get here on a DRC miss.
	 */

	strhashval = clientstr_hashval(dname);

	nfs4_lock_state();
	conf = find_confirmed_client_by_str(dname, strhashval, false);
	if (conf) {
		/* RFC 3530 14.2.33 CASE 0: */
		status = nfserr_clid_inuse;
		if (!same_creds(&conf->cl_cred, &rqstp->rq_cred)) {
			char addr_str[INET6_ADDRSTRLEN];
			rpc_ntop((struct sockaddr *) &conf->cl_addr, addr_str,
				 sizeof(addr_str));
			dprintk("NFSD: setclientid: string in use by client "
				"at %s\n", addr_str);
			goto out;
		}
	}
	/*
	 * section 14.2.33 of RFC 3530 (under the heading "IMPLEMENTATION")
	 * has a description of SETCLIENTID request processing consisting
	 * of 5 bullet points, labeled as CASE0 - CASE4 below.
	 */
	unconf = find_unconfirmed_client_by_str(dname, strhashval, false);
	status = nfserr_resource;
	if (!conf) {
		/*
		 * RFC 3530 14.2.33 CASE 4:
		 * placed first, because it is the normal case
		 */
		if (unconf)
			expire_client(unconf);
		new = create_client(clname, dname, rqstp, &clverifier);
		if (new == NULL)
			goto out;
		gen_clid(new);
	} else if (same_verf(&conf->cl_verifier, &clverifier)) {
		/*
		 * RFC 3530 14.2.33 CASE 1:
		 * probable callback update
		 */
		if (unconf) {
			/* Note this is removing unconfirmed {*x***},
			 * which is stronger than RFC recommended {vxc**}.
			 * This has the advantage that there is at most
			 * one {*x***} in either list at any time.
			 */
			expire_client(unconf);
		}
		new = create_client(clname, dname, rqstp, &clverifier);
		if (new == NULL)
			goto out;
		copy_clid(new, conf);
	} else if (!unconf) {
		/*
		 * RFC 3530 14.2.33 CASE 2:
		 * probable client reboot; state will be removed if
		 * confirmed.
		 */
		new = create_client(clname, dname, rqstp, &clverifier);
		if (new == NULL)
			goto out;
		gen_clid(new);
	} else {
		/*
		 * RFC 3530 14.2.33 CASE 3:
		 * probable client reboot; state will be removed if
		 * confirmed.
		 */
		expire_client(unconf);
		new = create_client(clname, dname, rqstp, &clverifier);
		if (new == NULL)
			goto out;
		gen_clid(new);
	}
	gen_callback(new, setclid, rpc_get_scope_id(sa));
	add_to_unconfirmed(new, strhashval);
	setclid->se_clientid.cl_boot = new->cl_clientid.cl_boot;
	setclid->se_clientid.cl_id = new->cl_clientid.cl_id;
	memcpy(setclid->se_confirm.data, new->cl_confirm.data, sizeof(setclid->se_confirm.data));
	status = nfs_ok;
out:
	nfs4_unlock_state();
	return status;
}


/*
 * Section 14.2.34 of RFC 3530 (under the heading "IMPLEMENTATION") has
 * a description of SETCLIENTID_CONFIRM request processing consisting of 4
 * bullets, labeled as CASE1 - CASE4 below.
 */
__be32
nfsd4_setclientid_confirm(struct svc_rqst *rqstp,
			 struct nfsd4_compound_state *cstate,
			 struct nfsd4_setclientid_confirm *setclientid_confirm)
{
	struct sockaddr *sa = svc_addr(rqstp);
	struct nfs4_client *conf, *unconf;
	nfs4_verifier confirm = setclientid_confirm->sc_confirm; 
	clientid_t * clid = &setclientid_confirm->sc_clientid;
	__be32 status;

	if (STALE_CLIENTID(clid))
		return nfserr_stale_clientid;
	/* 
	 * XXX The Duplicate Request Cache (DRC) has been checked (??)
	 * We get here on a DRC miss.
	 */

	nfs4_lock_state();

	conf = find_confirmed_client(clid);
	unconf = find_unconfirmed_client(clid);

	status = nfserr_clid_inuse;
	if (conf && !rpc_cmp_addr((struct sockaddr *) &conf->cl_addr, sa))
		goto out;
	if (unconf && !rpc_cmp_addr((struct sockaddr *) &unconf->cl_addr, sa))
		goto out;

	/*
	 * section 14.2.34 of RFC 3530 has a description of
	 * SETCLIENTID_CONFIRM request processing consisting
	 * of 4 bullet points, labeled as CASE1 - CASE4 below.
	 */
	if (conf && unconf && same_verf(&confirm, &unconf->cl_confirm)) {
		/*
		 * RFC 3530 14.2.34 CASE 1:
		 * callback update
		 */
		if (!same_creds(&conf->cl_cred, &unconf->cl_cred))
			status = nfserr_clid_inuse;
		else {
			/* XXX: We just turn off callbacks until we can handle
			  * change request correctly. */
			atomic_set(&conf->cl_cb_conn.cb_set, 0);
			expire_client(unconf);
			status = nfs_ok;

		}
	} else if (conf && !unconf) {
		/*
		 * RFC 3530 14.2.34 CASE 2:
		 * probable retransmitted request; play it safe and
		 * do nothing.
		 */
		if (!same_creds(&conf->cl_cred, &rqstp->rq_cred))
			status = nfserr_clid_inuse;
		else
			status = nfs_ok;
	} else if (!conf && unconf
			&& same_verf(&unconf->cl_confirm, &confirm)) {
		/*
		 * RFC 3530 14.2.34 CASE 3:
		 * Normal case; new or rebooted client:
		 */
		if (!same_creds(&unconf->cl_cred, &rqstp->rq_cred)) {
			status = nfserr_clid_inuse;
		} else {
			unsigned int hash =
				clientstr_hashval(unconf->cl_recdir);
			conf = find_confirmed_client_by_str(unconf->cl_recdir,
							    hash, false);
			if (conf) {
				nfsd4_remove_clid_dir(conf);
				expire_client(conf);
			}
			move_to_confirmed(unconf);
			conf = unconf;
			nfsd4_probe_callback(conf);
			status = nfs_ok;
		}
	} else if ((!conf || (conf && !same_verf(&conf->cl_confirm, &confirm)))
	    && (!unconf || (unconf && !same_verf(&unconf->cl_confirm,
				    				&confirm)))) {
		/*
		 * RFC 3530 14.2.34 CASE 4:
		 * Client probably hasn't noticed that we rebooted yet.
		 */
		status = nfserr_stale_clientid;
	} else {
		/* check that we have hit one of the cases...*/
		status = nfserr_clid_inuse;
	}
out:
	nfs4_unlock_state();
	return status;
}

/* OPEN Share state helper functions */
static inline struct nfs4_file *
alloc_init_file(struct inode *ino)
{
	struct nfs4_file *fp;
	unsigned int hashval = file_hashval(ino);

	fp = kmem_cache_alloc(file_slab, GFP_KERNEL);
	if (fp) {
		atomic_set(&fp->fi_ref, 1);
		INIT_LIST_HEAD(&fp->fi_hash);
		INIT_LIST_HEAD(&fp->fi_stateids);
		INIT_LIST_HEAD(&fp->fi_delegations);
		spin_lock(&recall_lock);
		list_add(&fp->fi_hash, &file_hashtbl[hashval]);
		spin_unlock(&recall_lock);
		fp->fi_inode = igrab(ino);
		fp->fi_id = current_fileid++;
		fp->fi_had_conflict = false;
		return fp;
	}
	return NULL;
}

static void
nfsd4_free_slab(struct kmem_cache **slab)
{
	if (*slab == NULL)
		return;
	kmem_cache_destroy(*slab);
	*slab = NULL;
}

void
nfsd4_free_slabs(void)
{
	nfsd4_free_slab(&stateowner_slab);
	nfsd4_free_slab(&file_slab);
	nfsd4_free_slab(&stateid_slab);
	nfsd4_free_slab(&deleg_slab);
}

static int
nfsd4_init_slabs(void)
{
	stateowner_slab = kmem_cache_create("nfsd4_stateowners",
			sizeof(struct nfs4_stateowner), 0, 0, NULL);
	if (stateowner_slab == NULL)
		goto out_nomem;
	file_slab = kmem_cache_create("nfsd4_files",
			sizeof(struct nfs4_file), 0, 0, NULL);
	if (file_slab == NULL)
		goto out_nomem;
	stateid_slab = kmem_cache_create("nfsd4_stateids",
			sizeof(struct nfs4_stateid), 0, 0, NULL);
	if (stateid_slab == NULL)
		goto out_nomem;
	deleg_slab = kmem_cache_create("nfsd4_delegations",
			sizeof(struct nfs4_delegation), 0, 0, NULL);
	if (deleg_slab == NULL)
		goto out_nomem;
	return 0;
out_nomem:
	nfsd4_free_slabs();
	dprintk("nfsd4: out of memory while initializing nfsv4\n");
	return -ENOMEM;
}

void
nfs4_free_stateowner(struct kref *kref)
{
	struct nfs4_stateowner *sop =
		container_of(kref, struct nfs4_stateowner, so_ref);
	kfree(sop->so_owner.data);
	kmem_cache_free(stateowner_slab, sop);
}

static inline struct nfs4_stateowner *
alloc_stateowner(struct xdr_netobj *owner)
{
	struct nfs4_stateowner *sop;

	if ((sop = kmem_cache_alloc(stateowner_slab, GFP_KERNEL))) {
		if ((sop->so_owner.data = kmalloc(owner->len, GFP_KERNEL))) {
			memcpy(sop->so_owner.data, owner->data, owner->len);
			sop->so_owner.len = owner->len;
			kref_init(&sop->so_ref);
			return sop;
		} 
		kmem_cache_free(stateowner_slab, sop);
	}
	return NULL;
}

static struct nfs4_stateowner *
alloc_init_open_stateowner(unsigned int strhashval, struct nfs4_client *clp, struct nfsd4_open *open) {
	struct nfs4_stateowner *sop;
	struct nfs4_replay *rp;
	unsigned int idhashval;

	if (!(sop = alloc_stateowner(&open->op_owner)))
		return NULL;
	idhashval = ownerid_hashval(current_ownerid);
	INIT_LIST_HEAD(&sop->so_idhash);
	INIT_LIST_HEAD(&sop->so_strhash);
	INIT_LIST_HEAD(&sop->so_perclient);
	INIT_LIST_HEAD(&sop->so_stateids);
	INIT_LIST_HEAD(&sop->so_perstateid);  /* not used */
	INIT_LIST_HEAD(&sop->so_close_lru);
	sop->so_time = 0;
	list_add(&sop->so_idhash, &ownerid_hashtbl[idhashval]);
	list_add(&sop->so_strhash, &ownerstr_hashtbl[strhashval]);
	list_add(&sop->so_perclient, &clp->cl_openowners);
	sop->so_is_open_owner = 1;
	sop->so_id = current_ownerid++;
	sop->so_client = clp;
	sop->so_seqid = open->op_seqid;
	sop->so_confirmed = 0;
	rp = &sop->so_replay;
	rp->rp_status = nfserr_serverfault;
	rp->rp_buflen = 0;
	rp->rp_buf = rp->rp_ibuf;
	return sop;
}

static inline void
init_stateid(struct nfs4_stateid *stp, struct nfs4_file *fp, struct nfsd4_open *open) {
	struct nfs4_stateowner *sop = open->op_stateowner;
	unsigned int hashval = stateid_hashval(sop->so_id, fp->fi_id);

	INIT_LIST_HEAD(&stp->st_hash);
	INIT_LIST_HEAD(&stp->st_perstateowner);
	INIT_LIST_HEAD(&stp->st_lockowners);
	INIT_LIST_HEAD(&stp->st_perfile);
	list_add(&stp->st_hash, &stateid_hashtbl[hashval]);
	list_add(&stp->st_perstateowner, &sop->so_stateids);
	list_add(&stp->st_perfile, &fp->fi_stateids);
	stp->st_stateowner = sop;
	get_nfs4_file(fp);
	stp->st_file = fp;
	stp->st_stateid.si_boot = get_seconds();
	stp->st_stateid.si_stateownerid = sop->so_id;
	stp->st_stateid.si_fileid = fp->fi_id;
	stp->st_stateid.si_generation = 0;
	stp->st_access_bmap = 0;
	stp->st_deny_bmap = 0;
	__set_bit(open->op_share_access & ~NFS4_SHARE_WANT_MASK,
		  &stp->st_access_bmap);
	__set_bit(open->op_share_deny, &stp->st_deny_bmap);
	stp->st_openstp = NULL;
}

static void
move_to_close_lru(struct nfs4_stateowner *sop)
{
	dprintk("NFSD: move_to_close_lru nfs4_stateowner %p\n", sop);

	list_move_tail(&sop->so_close_lru, &close_lru);
	sop->so_time = get_seconds();
}

static int
same_owner_str(struct nfs4_stateowner *sop, struct xdr_netobj *owner,
							clientid_t *clid)
{
	return (sop->so_owner.len == owner->len) &&
		0 == memcmp(sop->so_owner.data, owner->data, owner->len) &&
		(sop->so_client->cl_clientid.cl_id == clid->cl_id);
}

static struct nfs4_stateowner *
find_openstateowner_str(unsigned int hashval, struct nfsd4_open *open)
{
	struct nfs4_stateowner *so = NULL;

	list_for_each_entry(so, &ownerstr_hashtbl[hashval], so_strhash) {
		if (same_owner_str(so, &open->op_owner, &open->op_clientid))
			return so;
	}
	return NULL;
}

/* search file_hashtbl[] for file */
static struct nfs4_file *
find_file(struct inode *ino)
{
	unsigned int hashval = file_hashval(ino);
	struct nfs4_file *fp;

	spin_lock(&recall_lock);
	list_for_each_entry(fp, &file_hashtbl[hashval], fi_hash) {
		if (fp->fi_inode == ino) {
			get_nfs4_file(fp);
			spin_unlock(&recall_lock);
			return fp;
		}
	}
	spin_unlock(&recall_lock);
	return NULL;
}

static inline int access_valid(u32 x, u32 minorversion)
{
	if ((x & NFS4_SHARE_ACCESS_MASK) < NFS4_SHARE_ACCESS_READ)
		return 0;
	if ((x & NFS4_SHARE_ACCESS_MASK) > NFS4_SHARE_ACCESS_BOTH)
		return 0;
	x &= ~NFS4_SHARE_ACCESS_MASK;
	if (minorversion && x) {
		if ((x & NFS4_SHARE_WANT_MASK) > NFS4_SHARE_WANT_CANCEL)
			return 0;
		if ((x & NFS4_SHARE_WHEN_MASK) > NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED)
			return 0;
		x &= ~(NFS4_SHARE_WANT_MASK | NFS4_SHARE_WHEN_MASK);
	}
	if (x)
		return 0;
	return 1;
}

static inline int deny_valid(u32 x)
{
	/* Note: unlike access bits, deny bits may be zero. */
	return x <= NFS4_SHARE_DENY_BOTH;
}

/*
 * We store the NONE, READ, WRITE, and BOTH bits separately in the
 * st_{access,deny}_bmap field of the stateid, in order to track not
 * only what share bits are currently in force, but also what
 * combinations of share bits previous opens have used.  This allows us
 * to enforce the recommendation of rfc 3530 14.2.19 that the server
 * return an error if the client attempt to downgrade to a combination
 * of share bits not explicable by closing some of its previous opens.
 *
 * XXX: This enforcement is actually incomplete, since we don't keep
 * track of access/deny bit combinations; so, e.g., we allow:
 *
 *	OPEN allow read, deny write
 *	OPEN allow both, deny none
 *	DOWNGRADE allow read, deny none
 *
 * which we should reject.
 */
static void
set_access(unsigned int *access, unsigned long bmap) {
	int i;

	*access = 0;
	for (i = 1; i < 4; i++) {
		if (test_bit(i, &bmap))
			*access |= i;
	}
}

static void
set_deny(unsigned int *deny, unsigned long bmap) {
	int i;

	*deny = 0;
	for (i = 0; i < 4; i++) {
		if (test_bit(i, &bmap))
			*deny |= i ;
	}
}

static int
test_share(struct nfs4_stateid *stp, struct nfsd4_open *open) {
	unsigned int access, deny;

	set_access(&access, stp->st_access_bmap);
	set_deny(&deny, stp->st_deny_bmap);
	if ((access & open->op_share_deny) || (deny & open->op_share_access))
		return 0;
	return 1;
}

/*
 * Called to check deny when READ with all zero stateid or
 * WRITE with all zero or all one stateid
 */
static __be32
nfs4_share_conflict(struct svc_fh *current_fh, unsigned int deny_type)
{
	struct inode *ino = current_fh->fh_dentry->d_inode;
	struct nfs4_file *fp;
	struct nfs4_stateid *stp;
	__be32 ret;

	dprintk("NFSD: nfs4_share_conflict\n");

	fp = find_file(ino);
	if (!fp)
		return nfs_ok;
	ret = nfserr_locked;
	/* Search for conflicting share reservations */
	list_for_each_entry(stp, &fp->fi_stateids, st_perfile) {
		if (test_bit(deny_type, &stp->st_deny_bmap) ||
		    test_bit(NFS4_SHARE_DENY_BOTH, &stp->st_deny_bmap))
			goto out;
	}
	ret = nfs_ok;
out:
	put_nfs4_file(fp);
	return ret;
}

static inline void
nfs4_file_downgrade(struct file *filp, unsigned int share_access)
{
	if (share_access & NFS4_SHARE_ACCESS_WRITE) {
		drop_file_write_access(filp);
		filp->f_mode = (filp->f_mode | FMODE_READ) & ~FMODE_WRITE;
	}
}

/*
 * Spawn a thread to perform a recall on the delegation represented
 * by the lease (file_lock)
 *
 * Called from break_lease() with lock_kernel() held.
 * Note: we assume break_lease will only call this *once* for any given
 * lease.
 */
static
void nfsd_break_deleg_cb(struct file_lock *fl)
{
	struct nfs4_delegation *dp = (struct nfs4_delegation *)fl->fl_owner;

	dprintk("NFSD nfsd_break_deleg_cb: dp %p fl %p\n",dp,fl);
	if (!dp)
		return;

	/* We're assuming the state code never drops its reference
	 * without first removing the lease.  Since we're in this lease
	 * callback (and since the lease code is serialized by the kernel
	 * lock) we know the server hasn't removed the lease yet, we know
	 * it's safe to take a reference: */
	atomic_inc(&dp->dl_count);
	atomic_inc(&dp->dl_client->cl_count);

	spin_lock(&recall_lock);
	list_add_tail(&dp->dl_recall_lru, &del_recall_lru);
	spin_unlock(&recall_lock);

	/* only place dl_time is set. protected by lock_kernel*/
	dp->dl_time = get_seconds();

	/*
	 * We don't want the locks code to timeout the lease for us;
	 * we'll remove it ourself if the delegation isn't returned
	 * in time.
	 */
	fl->fl_break_time = 0;

	dp->dl_file->fi_had_conflict = true;
	nfsd4_cb_recall(dp);
}

/*
 * The file_lock is being reapd.
 *
 * Called by locks_free_lock() with lock_kernel() held.
 */
static
void nfsd_release_deleg_cb(struct file_lock *fl)
{
	struct nfs4_delegation *dp = (struct nfs4_delegation *)fl->fl_owner;

	dprintk("NFSD nfsd_release_deleg_cb: fl %p dp %p dl_count %d\n", fl,dp, atomic_read(&dp->dl_count));

	if (!(fl->fl_flags & FL_LEASE) || !dp)
		return;
	dp->dl_flock = NULL;
}

/*
 * Set the delegation file_lock back pointer.
 *
 * Called from setlease() with lock_kernel() held.
 */
static
void nfsd_copy_lock_deleg_cb(struct file_lock *new, struct file_lock *fl)
{
	struct nfs4_delegation *dp = (struct nfs4_delegation *)new->fl_owner;

	dprintk("NFSD: nfsd_copy_lock_deleg_cb: new fl %p dp %p\n", new, dp);
	if (!dp)
		return;
	dp->dl_flock = new;
}

/*
 * Called from setlease() with lock_kernel() held
 */
static
int nfsd_same_client_deleg_cb(struct file_lock *onlist, struct file_lock *try)
{
	struct nfs4_delegation *onlistd =
		(struct nfs4_delegation *)onlist->fl_owner;
	struct nfs4_delegation *tryd =
		(struct nfs4_delegation *)try->fl_owner;

	if (onlist->fl_lmops != try->fl_lmops)
		return 0;

	return onlistd->dl_client == tryd->dl_client;
}


static
int nfsd_change_deleg_cb(struct file_lock **onlist, int arg)
{
	if (arg & F_UNLCK)
		return lease_modify(onlist, arg);
	else
		return -EAGAIN;
}

static const struct lock_manager_operations nfsd_lease_mng_ops = {
	.fl_break = nfsd_break_deleg_cb,
	.fl_release_private = nfsd_release_deleg_cb,
	.fl_copy_lock = nfsd_copy_lock_deleg_cb,
	.fl_mylease = nfsd_same_client_deleg_cb,
	.fl_change = nfsd_change_deleg_cb,
};


__be32
nfsd4_process_open1(struct nfsd4_compound_state *cstate,
		    struct nfsd4_open *open)
{
	clientid_t *clientid = &open->op_clientid;
	struct nfs4_client *clp = NULL;
	unsigned int strhashval;
	struct nfs4_stateowner *sop = NULL;

	if (!check_name(open->op_owner))
		return nfserr_inval;

	if (STALE_CLIENTID(&open->op_clientid))
		return nfserr_stale_clientid;

	strhashval = ownerstr_hashval(clientid->cl_id, open->op_owner);
	sop = find_openstateowner_str(strhashval, open);
	open->op_stateowner = sop;
	if (!sop) {
		/* Make sure the client's lease hasn't expired. */
		clp = find_confirmed_client(clientid);
		if (clp == NULL)
			return nfserr_expired;
		goto renew;
	}
	/* When sessions are used, skip open sequenceid processing */
	if (nfsd4_has_session(cstate))
		goto renew;
	if (!sop->so_confirmed) {
		/* Replace unconfirmed owners without checking for replay. */
		clp = sop->so_client;
		release_openowner(sop);
		open->op_stateowner = NULL;
		goto renew;
	}
	if (open->op_seqid == sop->so_seqid - 1) {
		if (sop->so_replay.rp_buflen)
			return nfserr_replay_me;
		/* The original OPEN failed so spectacularly
		 * that we don't even have replay data saved!
		 * Therefore, we have no choice but to continue
		 * processing this OPEN; presumably, we'll
		 * fail again for the same reason.
		 */
		dprintk("nfsd4_process_open1: replay with no replay cache\n");
		goto renew;
	}
	if (open->op_seqid != sop->so_seqid)
		return nfserr_bad_seqid;
renew:
	if (open->op_stateowner == NULL) {
		sop = alloc_init_open_stateowner(strhashval, clp, open);
		if (sop == NULL)
			return nfserr_resource;
		open->op_stateowner = sop;
	}
	list_del_init(&sop->so_close_lru);
	renew_client(sop->so_client);
	return nfs_ok;
}

static inline __be32
nfs4_check_delegmode(struct nfs4_delegation *dp, int flags)
{
	if ((flags & WR_STATE) && (dp->dl_type == NFS4_OPEN_DELEGATE_READ))
		return nfserr_openmode;
	else
		return nfs_ok;
}

static struct nfs4_delegation *
find_delegation_file(struct nfs4_file *fp, stateid_t *stid)
{
	struct nfs4_delegation *dp;

	list_for_each_entry(dp, &fp->fi_delegations, dl_perfile) {
		if (dp->dl_stateid.si_stateownerid == stid->si_stateownerid)
			return dp;
	}
	return NULL;
}

static __be32
nfs4_check_deleg(struct nfs4_file *fp, struct nfsd4_open *open,
		struct nfs4_delegation **dp)
{
	int flags;
	__be32 status = nfserr_bad_stateid;

	*dp = find_delegation_file(fp, &open->op_delegate_stateid);
	if (*dp == NULL)
		goto out;
	flags = open->op_share_access == NFS4_SHARE_ACCESS_READ ?
						RD_STATE : WR_STATE;
	status = nfs4_check_delegmode(*dp, flags);
	if (status)
		*dp = NULL;
out:
	if (open->op_claim_type != NFS4_OPEN_CLAIM_DELEGATE_CUR)
		return nfs_ok;
	if (status)
		return status;
	open->op_stateowner->so_confirmed = 1;
	return nfs_ok;
}

static __be32
nfs4_check_open(struct nfs4_file *fp, struct nfsd4_open *open, struct nfs4_stateid **stpp)
{
	struct nfs4_stateid *local;
	__be32 status = nfserr_share_denied;
	struct nfs4_stateowner *sop = open->op_stateowner;

	list_for_each_entry(local, &fp->fi_stateids, st_perfile) {
		/* ignore lock owners */
		if (local->st_stateowner->so_is_open_owner == 0)
			continue;
		/* remember if we have seen this open owner */
		if (local->st_stateowner == sop)
			*stpp = local;
		/* check for conflicting share reservations */
		if (!test_share(local, open))
			goto out;
	}
	status = 0;
out:
	return status;
}

static inline struct nfs4_stateid *
nfs4_alloc_stateid(void)
{
	return kmem_cache_alloc(stateid_slab, GFP_KERNEL);
}

static __be32
nfs4_new_open(struct svc_rqst *rqstp, struct nfs4_stateid **stpp,
		struct nfs4_delegation *dp,
		struct svc_fh *cur_fh, int flags)
{
	struct nfs4_stateid *stp;

	stp = nfs4_alloc_stateid();
	if (stp == NULL)
		return nfserr_resource;

	if (dp) {
		get_file(dp->dl_vfs_file);
		stp->st_vfs_file = dp->dl_vfs_file;
	} else {
		__be32 status;
		status = nfsd_open(rqstp, cur_fh, S_IFREG, flags,
				&stp->st_vfs_file);
		if (status) {
			if (status == nfserr_dropit)
				status = nfserr_jukebox;
			kmem_cache_free(stateid_slab, stp);
			return status;
		}
	}
	*stpp = stp;
	return 0;
}

static inline __be32
nfsd4_truncate(struct svc_rqst *rqstp, struct svc_fh *fh,
		struct nfsd4_open *open)
{
	struct iattr iattr = {
		.ia_valid = ATTR_SIZE,
		.ia_size = 0,
	};
	if (!open->op_truncate)
		return 0;
	if (!(open->op_share_access & NFS4_SHARE_ACCESS_WRITE))
		return nfserr_inval;
	return nfsd_setattr(rqstp, fh, &iattr, 0, (time_t)0);
}

static __be32
nfs4_upgrade_open(struct svc_rqst *rqstp, struct svc_fh *cur_fh, struct nfs4_stateid *stp, struct nfsd4_open *open)
{
	struct file *filp = stp->st_vfs_file;
	struct inode *inode = filp->f_path.dentry->d_inode;
	unsigned int share_access, new_writer;
	__be32 status;

	set_access(&share_access, stp->st_access_bmap);
	new_writer = (~share_access) & open->op_share_access
			& NFS4_SHARE_ACCESS_WRITE;

	if (new_writer) {
		int err = get_write_access(inode);
		if (err)
			return nfserrno(err);
		err = mnt_want_write(cur_fh->fh_export->ex_path.mnt);
		if (err)
			return nfserrno(err);
		file_take_write(filp);
	}
	status = nfsd4_truncate(rqstp, cur_fh, open);
	if (status) {
		if (new_writer)
			put_write_access(inode);
		return status;
	}
	/* remember the open */
	filp->f_mode |= open->op_share_access;
	__set_bit(open->op_share_access, &stp->st_access_bmap);
	__set_bit(open->op_share_deny, &stp->st_deny_bmap);

	return nfs_ok;
}


static void
nfs4_set_claim_prev(struct nfsd4_open *open)
{
	open->op_stateowner->so_confirmed = 1;
	open->op_stateowner->so_client->cl_firststate = 1;
}

/*
 * Attempt to hand out a delegation.
 */
static void
nfs4_open_delegation(struct svc_fh *fh, struct nfsd4_open *open, struct nfs4_stateid *stp)
{
	struct nfs4_delegation *dp;
	struct nfs4_stateowner *sop = stp->st_stateowner;
	struct nfs4_cb_conn *cb = &sop->so_client->cl_cb_conn;
	struct file_lock fl, *flp = &fl;
	int status, flag = 0;

	flag = NFS4_OPEN_DELEGATE_NONE;
	open->op_recall = 0;
	switch (open->op_claim_type) {
		case NFS4_OPEN_CLAIM_PREVIOUS:
			if (!atomic_read(&cb->cb_set))
				open->op_recall = 1;
			flag = open->op_delegate_type;
			if (flag == NFS4_OPEN_DELEGATE_NONE)
				goto out;
			break;
		case NFS4_OPEN_CLAIM_NULL:
			/* Let's not give out any delegations till everyone's
			 * had the chance to reclaim theirs.... */
			if (locks_in_grace())
				goto out;
			if (!atomic_read(&cb->cb_set) || !sop->so_confirmed)
				goto out;
			if (open->op_share_access & NFS4_SHARE_ACCESS_WRITE)
				flag = NFS4_OPEN_DELEGATE_WRITE;
			else
				flag = NFS4_OPEN_DELEGATE_READ;
			break;
		default:
			goto out;
	}

	dp = alloc_init_deleg(sop->so_client, stp, fh, flag);
	if (dp == NULL) {
		flag = NFS4_OPEN_DELEGATE_NONE;
		goto out;
	}
	locks_init_lock(&fl);
	fl.fl_lmops = &nfsd_lease_mng_ops;
	fl.fl_flags = FL_LEASE;
	fl.fl_type = flag == NFS4_OPEN_DELEGATE_READ? F_RDLCK: F_WRLCK;
	fl.fl_end = OFFSET_MAX;
	fl.fl_owner =  (fl_owner_t)dp;
	fl.fl_file = stp->st_vfs_file;
	fl.fl_pid = current->tgid;

	/* vfs_setlease checks to see if delegation should be handed out.
	 * the lock_manager callbacks fl_mylease and fl_change are used
	 */
	if ((status = vfs_setlease(stp->st_vfs_file, fl.fl_type, &flp))) {
		dprintk("NFSD: setlease failed [%d], no delegation\n", status);
		unhash_delegation(dp);
		flag = NFS4_OPEN_DELEGATE_NONE;
		goto out;
	}

	memcpy(&open->op_delegate_stateid, &dp->dl_stateid, sizeof(dp->dl_stateid));

	dprintk("NFSD: delegation stateid=" STATEID_FMT "\n",
		STATEID_VAL(&dp->dl_stateid));
out:
	if (open->op_claim_type == NFS4_OPEN_CLAIM_PREVIOUS
			&& flag == NFS4_OPEN_DELEGATE_NONE
			&& open->op_delegate_type != NFS4_OPEN_DELEGATE_NONE)
		dprintk("NFSD: WARNING: refusing delegation reclaim\n");
	open->op_delegate_type = flag;
}

/*
 * called with nfs4_lock_state() held.
 */
__be32
nfsd4_process_open2(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_open *open)
{
	struct nfsd4_compoundres *resp = rqstp->rq_resp;
	struct nfs4_file *fp = NULL;
	struct inode *ino = current_fh->fh_dentry->d_inode;
	struct nfs4_stateid *stp = NULL;
	struct nfs4_delegation *dp = NULL;
	__be32 status;

	status = nfserr_inval;
	if (!access_valid(open->op_share_access, resp->cstate.minorversion)
			|| !deny_valid(open->op_share_deny))
		goto out;
	/*
	 * Lookup file; if found, lookup stateid and check open request,
	 * and check for delegations in the process of being recalled.
	 * If not found, create the nfs4_file struct
	 */
	fp = find_file(ino);
	if (fp) {
		if ((status = nfs4_check_open(fp, open, &stp)))
			goto out;
		status = nfs4_check_deleg(fp, open, &dp);
		if (status)
			goto out;
	} else {
		status = nfserr_bad_stateid;
		if (open->op_claim_type == NFS4_OPEN_CLAIM_DELEGATE_CUR)
			goto out;
		status = nfserr_resource;
		fp = alloc_init_file(ino);
		if (fp == NULL)
			goto out;
	}

	/*
	 * OPEN the file, or upgrade an existing OPEN.
	 * If truncate fails, the OPEN fails.
	 */
	if (stp) {
		/* Stateid was found, this is an OPEN upgrade */
		status = nfs4_upgrade_open(rqstp, current_fh, stp, open);
		if (status)
			goto out;
		update_stateid(&stp->st_stateid);
	} else {
		/* Stateid was not found, this is a new OPEN */
		int flags = 0;
		if (open->op_share_access & NFS4_SHARE_ACCESS_READ)
			flags |= NFSD_MAY_READ;
		if (open->op_share_access & NFS4_SHARE_ACCESS_WRITE)
			flags |= NFSD_MAY_WRITE;
		status = nfs4_new_open(rqstp, &stp, dp, current_fh, flags);
		if (status)
			goto out;
		init_stateid(stp, fp, open);
		status = nfsd4_truncate(rqstp, current_fh, open);
		if (status) {
			release_open_stateid(stp);
			goto out;
		}
		if (nfsd4_has_session(&resp->cstate))
			update_stateid(&stp->st_stateid);
	}
	memcpy(&open->op_stateid, &stp->st_stateid, sizeof(stateid_t));

	if (nfsd4_has_session(&resp->cstate))
		open->op_stateowner->so_confirmed = 1;

	/*
	* Attempt to hand out a delegation. No error return, because the
	* OPEN succeeds even if we fail.
	*/
	nfs4_open_delegation(current_fh, open, stp);

	status = nfs_ok;

	dprintk("%s: stateid=" STATEID_FMT "\n", __func__,
		STATEID_VAL(&stp->st_stateid));
out:
	if (fp)
		put_nfs4_file(fp);
	if (status == 0 && open->op_claim_type == NFS4_OPEN_CLAIM_PREVIOUS)
		nfs4_set_claim_prev(open);
	/*
	* To finish the open response, we just need to set the rflags.
	*/
	open->op_rflags = NFS4_OPEN_RESULT_LOCKTYPE_POSIX;
	if (!open->op_stateowner->so_confirmed &&
	    !nfsd4_has_session(&resp->cstate))
		open->op_rflags |= NFS4_OPEN_RESULT_CONFIRM;

	return status;
}

__be32
nfsd4_renew(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	    clientid_t *clid)
{
	struct nfs4_client *clp;
	__be32 status;

	nfs4_lock_state();
	dprintk("process_renew(%08x/%08x): starting\n", 
			clid->cl_boot, clid->cl_id);
	status = nfserr_stale_clientid;
	if (STALE_CLIENTID(clid))
		goto out;
	clp = find_confirmed_client(clid);
	status = nfserr_expired;
	if (clp == NULL) {
		/* We assume the client took too long to RENEW. */
		dprintk("nfsd4_renew: clientid not found!\n");
		goto out;
	}
	renew_client(clp);
	status = nfserr_cb_path_down;
	if (!list_empty(&clp->cl_delegations)
			&& !atomic_read(&clp->cl_cb_conn.cb_set))
		goto out;
	status = nfs_ok;
out:
	nfs4_unlock_state();
	return status;
}

struct lock_manager nfsd4_manager = {
};

static void
nfsd4_end_grace(void)
{
	dprintk("NFSD: end of grace period\n");
	nfsd4_recdir_purge_old();
	locks_end_grace(&nfsd4_manager);
}

static time_t
nfs4_laundromat(void)
{
	struct nfs4_client *clp;
	struct nfs4_stateowner *sop;
	struct nfs4_delegation *dp;
	struct list_head *pos, *next, reaplist;
	time_t cutoff = get_seconds() - NFSD_LEASE_TIME;
	time_t t, clientid_val = NFSD_LEASE_TIME;
	time_t u, test_val = NFSD_LEASE_TIME;

	nfs4_lock_state();

	dprintk("NFSD: laundromat service - starting\n");
	if (locks_in_grace())
		nfsd4_end_grace();
	list_for_each_safe(pos, next, &client_lru) {
		clp = list_entry(pos, struct nfs4_client, cl_lru);
		if (time_after((unsigned long)clp->cl_time, (unsigned long)cutoff)) {
			t = clp->cl_time - cutoff;
			if (clientid_val > t)
				clientid_val = t;
			break;
		}
		dprintk("NFSD: purging unused client (clientid %08x)\n",
			clp->cl_clientid.cl_id);
		nfsd4_remove_clid_dir(clp);
		expire_client(clp);
	}
	INIT_LIST_HEAD(&reaplist);
	spin_lock(&recall_lock);
	list_for_each_safe(pos, next, &del_recall_lru) {
		dp = list_entry (pos, struct nfs4_delegation, dl_recall_lru);
		if (time_after((unsigned long)dp->dl_time, (unsigned long)cutoff)) {
			u = dp->dl_time - cutoff;
			if (test_val > u)
				test_val = u;
			break;
		}
		dprintk("NFSD: purging unused delegation dp %p, fp %p\n",
			            dp, dp->dl_flock);
		list_move(&dp->dl_recall_lru, &reaplist);
	}
	spin_unlock(&recall_lock);
	list_for_each_safe(pos, next, &reaplist) {
		dp = list_entry (pos, struct nfs4_delegation, dl_recall_lru);
		list_del_init(&dp->dl_recall_lru);
		unhash_delegation(dp);
	}
	test_val = NFSD_LEASE_TIME;
	list_for_each_safe(pos, next, &close_lru) {
		sop = list_entry(pos, struct nfs4_stateowner, so_close_lru);
		if (time_after((unsigned long)sop->so_time, (unsigned long)cutoff)) {
			u = sop->so_time - cutoff;
			if (test_val > u)
				test_val = u;
			break;
		}
		dprintk("NFSD: purging unused open stateowner (so_id %d)\n",
			sop->so_id);
		release_openowner(sop);
	}
	if (clientid_val < NFSD_LAUNDROMAT_MINTIMEOUT)
		clientid_val = NFSD_LAUNDROMAT_MINTIMEOUT;
	nfs4_unlock_state();
	return clientid_val;
}

static struct workqueue_struct *laundry_wq;
static void laundromat_main(struct work_struct *);
static DECLARE_DELAYED_WORK(laundromat_work, laundromat_main);

static void
laundromat_main(struct work_struct *not_used)
{
	time_t t;

	t = nfs4_laundromat();
	dprintk("NFSD: laundromat_main - sleeping for %ld seconds\n", t);
	queue_delayed_work(laundry_wq, &laundromat_work, t*HZ);
}

static struct nfs4_stateowner *
search_close_lru(u32 st_id, int flags)
{
	struct nfs4_stateowner *local = NULL;

	if (flags & CLOSE_STATE) {
		list_for_each_entry(local, &close_lru, so_close_lru) {
			if (local->so_id == st_id)
				return local;
		}
	}
	return NULL;
}

static inline int
nfs4_check_fh(struct svc_fh *fhp, struct nfs4_stateid *stp)
{
	return fhp->fh_dentry->d_inode != stp->st_vfs_file->f_path.dentry->d_inode;
}

static int
STALE_STATEID(stateid_t *stateid)
{
	if (time_after((unsigned long)boot_time,
			(unsigned long)stateid->si_boot)) {
		dprintk("NFSD: stale stateid " STATEID_FMT "!\n",
			STATEID_VAL(stateid));
		return 1;
	}
	return 0;
}

static int
EXPIRED_STATEID(stateid_t *stateid)
{
	if (time_before((unsigned long)boot_time,
			((unsigned long)stateid->si_boot)) &&
	    time_before((unsigned long)(stateid->si_boot + lease_time), get_seconds())) {
		dprintk("NFSD: expired stateid " STATEID_FMT "!\n",
			STATEID_VAL(stateid));
		return 1;
	}
	return 0;
}

static __be32
stateid_error_map(stateid_t *stateid)
{
	if (STALE_STATEID(stateid))
		return nfserr_stale_stateid;
	if (EXPIRED_STATEID(stateid))
		return nfserr_expired;

	dprintk("NFSD: bad stateid " STATEID_FMT "!\n",
		STATEID_VAL(stateid));
	return nfserr_bad_stateid;
}

static inline int
access_permit_read(unsigned long access_bmap)
{
	return test_bit(NFS4_SHARE_ACCESS_READ, &access_bmap) ||
		test_bit(NFS4_SHARE_ACCESS_BOTH, &access_bmap) ||
		test_bit(NFS4_SHARE_ACCESS_WRITE, &access_bmap);
}

static inline int
access_permit_write(unsigned long access_bmap)
{
	return test_bit(NFS4_SHARE_ACCESS_WRITE, &access_bmap) ||
		test_bit(NFS4_SHARE_ACCESS_BOTH, &access_bmap);
}

static
__be32 nfs4_check_openmode(struct nfs4_stateid *stp, int flags)
{
        __be32 status = nfserr_openmode;

	if ((flags & WR_STATE) && (!access_permit_write(stp->st_access_bmap)))
                goto out;
	if ((flags & RD_STATE) && (!access_permit_read(stp->st_access_bmap)))
                goto out;
	status = nfs_ok;
out:
	return status;
}

static inline __be32
check_special_stateids(svc_fh *current_fh, stateid_t *stateid, int flags)
{
	if (ONE_STATEID(stateid) && (flags & RD_STATE))
		return nfs_ok;
	else if (locks_in_grace()) {
		/* Answer in remaining cases depends on existance of
		 * conflicting state; so we must wait out the grace period. */
		return nfserr_grace;
	} else if (flags & WR_STATE)
		return nfs4_share_conflict(current_fh,
				NFS4_SHARE_DENY_WRITE);
	else /* (flags & RD_STATE) && ZERO_STATEID(stateid) */
		return nfs4_share_conflict(current_fh,
				NFS4_SHARE_DENY_READ);
}

/*
 * Allow READ/WRITE during grace period on recovered state only for files
 * that are not able to provide mandatory locking.
 */
static inline int
grace_disallows_io(struct inode *inode)
{
	return locks_in_grace() && mandatory_lock(inode);
}

static int check_stateid_generation(stateid_t *in, stateid_t *ref, int flags)
{
	/*
	 * When sessions are used the stateid generation number is ignored
	 * when it is zero.
	 */
	if ((flags & HAS_SESSION) && in->si_generation == 0)
		goto out;

	/* If the client sends us a stateid from the future, it's buggy: */
	if (in->si_generation > ref->si_generation)
		return nfserr_bad_stateid;
	/*
	 * The following, however, can happen.  For example, if the
	 * client sends an open and some IO at the same time, the open
	 * may bump si_generation while the IO is still in flight.
	 * Thanks to hard links and renames, the client never knows what
	 * file an open will affect.  So it could avoid that situation
	 * only by serializing all opens and IO from the same open
	 * owner.  To recover from the old_stateid error, the client
	 * will just have to retry the IO:
	 */
	if (in->si_generation < ref->si_generation)
		return nfserr_old_stateid;
out:
	return nfs_ok;
}

static int is_delegation_stateid(stateid_t *stateid)
{
	return stateid->si_fileid == 0;
}

/*
* Checks for stateid operations
*/
__be32
nfs4_preprocess_stateid_op(struct nfsd4_compound_state *cstate,
			   stateid_t *stateid, int flags, struct file **filpp)
{
	struct nfs4_stateid *stp = NULL;
	struct nfs4_delegation *dp = NULL;
	struct svc_fh *current_fh = &cstate->current_fh;
	struct inode *ino = current_fh->fh_dentry->d_inode;
	__be32 status;

	if (filpp)
		*filpp = NULL;

	if (grace_disallows_io(ino))
		return nfserr_grace;

	if (nfsd4_has_session(cstate))
		flags |= HAS_SESSION;

	if (ZERO_STATEID(stateid) || ONE_STATEID(stateid))
		return check_special_stateids(current_fh, stateid, flags);

	status = nfserr_stale_stateid;
	if (STALE_STATEID(stateid)) 
		goto out;

	status = nfserr_bad_stateid;
	if (is_delegation_stateid(stateid)) {
		dp = find_delegation_stateid(ino, stateid);
		if (!dp) {
			status = stateid_error_map(stateid);
			goto out;
		}
		status = check_stateid_generation(stateid, &dp->dl_stateid,
						  flags);
		if (status)
			goto out;
		status = nfs4_check_delegmode(dp, flags);
		if (status)
			goto out;
		renew_client(dp->dl_client);
		if (filpp)
			*filpp = dp->dl_vfs_file;
	} else { /* open or lock stateid */
		stp = find_stateid(stateid, flags);
		if (!stp) {
			status = stateid_error_map(stateid);
			goto out;
		}
		if (nfs4_check_fh(current_fh, stp))
			goto out;
		if (!stp->st_stateowner->so_confirmed)
			goto out;
		status = check_stateid_generation(stateid, &stp->st_stateid,
						  flags);
		if (status)
			goto out;
		status = nfs4_check_openmode(stp, flags);
		if (status)
			goto out;
		renew_client(stp->st_stateowner->so_client);
		if (filpp)
			*filpp = stp->st_vfs_file;
	}
	status = nfs_ok;
out:
	return status;
}

static inline int
setlkflg (int type)
{
	return (type == NFS4_READW_LT || type == NFS4_READ_LT) ?
		RD_STATE : WR_STATE;
}

/* 
 * Checks for sequence id mutating operations. 
 */
static __be32
nfs4_preprocess_seqid_op(struct nfsd4_compound_state *cstate, u32 seqid,
			 stateid_t *stateid, int flags,
			 struct nfs4_stateowner **sopp,
			 struct nfs4_stateid **stpp, struct nfsd4_lock *lock)
{
	struct nfs4_stateid *stp;
	struct nfs4_stateowner *sop;
	struct svc_fh *current_fh = &cstate->current_fh;
	__be32 status;

	dprintk("NFSD: %s: seqid=%d stateid = " STATEID_FMT "\n", __func__,
		seqid, STATEID_VAL(stateid));

	*stpp = NULL;
	*sopp = NULL;

	if (ZERO_STATEID(stateid) || ONE_STATEID(stateid)) {
		dprintk("NFSD: preprocess_seqid_op: magic stateid!\n");
		return nfserr_bad_stateid;
	}

	if (STALE_STATEID(stateid))
		return nfserr_stale_stateid;

	if (nfsd4_has_session(cstate))
		flags |= HAS_SESSION;

	/*
	* We return BAD_STATEID if filehandle doesn't match stateid, 
	* the confirmed flag is incorrecly set, or the generation 
	* number is incorrect.  
	*/
	stp = find_stateid(stateid, flags);
	if (stp == NULL) {
		/*
		 * Also, we should make sure this isn't just the result of
		 * a replayed close:
		 */
		sop = search_close_lru(stateid->si_stateownerid, flags);
		if (sop == NULL)
			return stateid_error_map(stateid);
		*sopp = sop;
		goto check_replay;
	}

	*stpp = stp;
	*sopp = sop = stp->st_stateowner;

	if (lock) {
		clientid_t *lockclid = &lock->v.new.clientid;
		struct nfs4_client *clp = sop->so_client;
		int lkflg = 0;
		__be32 status;

		lkflg = setlkflg(lock->lk_type);

		if (lock->lk_is_new) {
			if (!sop->so_is_open_owner)
				return nfserr_bad_stateid;
			if (!(flags & HAS_SESSION) &&
			    !same_clid(&clp->cl_clientid, lockclid))
				return nfserr_bad_stateid;
			/* stp is the open stateid */
			status = nfs4_check_openmode(stp, lkflg);
			if (status)
				return status;
		} else {
			/* stp is the lock stateid */
			status = nfs4_check_openmode(stp->st_openstp, lkflg);
			if (status)
				return status;
               }
	}

	if (nfs4_check_fh(current_fh, stp)) {
		dprintk("NFSD: preprocess_seqid_op: fh-stateid mismatch!\n");
		return nfserr_bad_stateid;
	}

	/*
	*  We now validate the seqid and stateid generation numbers.
	*  For the moment, we ignore the possibility of 
	*  generation number wraparound.
	*/
	if (!(flags & HAS_SESSION) && seqid != sop->so_seqid)
		goto check_replay;

	if (sop->so_confirmed && flags & CONFIRM) {
		dprintk("NFSD: preprocess_seqid_op: expected"
				" unconfirmed stateowner!\n");
		return nfserr_bad_stateid;
	}
	if (!sop->so_confirmed && !(flags & CONFIRM)) {
		dprintk("NFSD: preprocess_seqid_op: stateowner not"
				" confirmed yet!\n");
		return nfserr_bad_stateid;
	}
	status = check_stateid_generation(stateid, &stp->st_stateid, flags);
	if (status)
		return status;
	renew_client(sop->so_client);
	return nfs_ok;

check_replay:
	if (seqid == sop->so_seqid - 1) {
		dprintk("NFSD: preprocess_seqid_op: retransmission?\n");
		/* indicate replay to calling function */
		return nfserr_replay_me;
	}
	dprintk("NFSD: preprocess_seqid_op: bad seqid (expected %d, got %d)\n",
			sop->so_seqid, seqid);
	*sopp = NULL;
	return nfserr_bad_seqid;
}

__be32
nfsd4_open_confirm(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
		   struct nfsd4_open_confirm *oc)
{
	__be32 status;
	struct nfs4_stateowner *sop;
	struct nfs4_stateid *stp;

	dprintk("NFSD: nfsd4_open_confirm on file %.*s\n",
			(int)cstate->current_fh.fh_dentry->d_name.len,
			cstate->current_fh.fh_dentry->d_name.name);

	status = fh_verify(rqstp, &cstate->current_fh, S_IFREG, 0);
	if (status)
		return status;

	nfs4_lock_state();

	if ((status = nfs4_preprocess_seqid_op(cstate,
					oc->oc_seqid, &oc->oc_req_stateid,
					CONFIRM | OPEN_STATE,
					&oc->oc_stateowner, &stp, NULL)))
		goto out; 

	sop = oc->oc_stateowner;
	sop->so_confirmed = 1;
	update_stateid(&stp->st_stateid);
	memcpy(&oc->oc_resp_stateid, &stp->st_stateid, sizeof(stateid_t));
	dprintk("NFSD: %s: success, seqid=%d stateid=" STATEID_FMT "\n",
		__func__, oc->oc_seqid, STATEID_VAL(&stp->st_stateid));

	nfsd4_create_clid_dir(sop->so_client);
out:
	if (oc->oc_stateowner) {
		nfs4_get_stateowner(oc->oc_stateowner);
		cstate->replay_owner = oc->oc_stateowner;
	}
	nfs4_unlock_state();
	return status;
}


/*
 * unset all bits in union bitmap (bmap) that
 * do not exist in share (from successful OPEN_DOWNGRADE)
 */
static void
reset_union_bmap_access(unsigned long access, unsigned long *bmap)
{
	int i;
	for (i = 1; i < 4; i++) {
		if ((i & access) != i)
			__clear_bit(i, bmap);
	}
}

static void
reset_union_bmap_deny(unsigned long deny, unsigned long *bmap)
{
	int i;
	for (i = 0; i < 4; i++) {
		if ((i & deny) != i)
			__clear_bit(i, bmap);
	}
}

__be32
nfsd4_open_downgrade(struct svc_rqst *rqstp,
		     struct nfsd4_compound_state *cstate,
		     struct nfsd4_open_downgrade *od)
{
	__be32 status;
	struct nfs4_stateid *stp;
	unsigned int share_access;

	dprintk("NFSD: nfsd4_open_downgrade on file %.*s\n", 
			(int)cstate->current_fh.fh_dentry->d_name.len,
			cstate->current_fh.fh_dentry->d_name.name);

	if (!access_valid(od->od_share_access, cstate->minorversion)
			|| !deny_valid(od->od_share_deny))
		return nfserr_inval;

	nfs4_lock_state();
	if ((status = nfs4_preprocess_seqid_op(cstate,
					od->od_seqid,
					&od->od_stateid, 
					OPEN_STATE,
					&od->od_stateowner, &stp, NULL)))
		goto out; 

	status = nfserr_inval;
	if (!test_bit(od->od_share_access, &stp->st_access_bmap)) {
		dprintk("NFSD:access not a subset current bitmap: 0x%lx, input access=%08x\n",
			stp->st_access_bmap, od->od_share_access);
		goto out;
	}
	if (!test_bit(od->od_share_deny, &stp->st_deny_bmap)) {
		dprintk("NFSD:deny not a subset current bitmap: 0x%lx, input deny=%08x\n",
			stp->st_deny_bmap, od->od_share_deny);
		goto out;
	}
	set_access(&share_access, stp->st_access_bmap);
	nfs4_file_downgrade(stp->st_vfs_file,
	                    share_access & ~od->od_share_access);

	reset_union_bmap_access(od->od_share_access, &stp->st_access_bmap);
	reset_union_bmap_deny(od->od_share_deny, &stp->st_deny_bmap);

	update_stateid(&stp->st_stateid);
	memcpy(&od->od_stateid, &stp->st_stateid, sizeof(stateid_t));
	status = nfs_ok;
out:
	if (od->od_stateowner) {
		nfs4_get_stateowner(od->od_stateowner);
		cstate->replay_owner = od->od_stateowner;
	}
	nfs4_unlock_state();
	return status;
}

/*
 * nfs4_unlock_state() called after encode
 */
__be32
nfsd4_close(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	    struct nfsd4_close *close)
{
	__be32 status;
	struct nfs4_stateid *stp;

	dprintk("NFSD: nfsd4_close on file %.*s\n", 
			(int)cstate->current_fh.fh_dentry->d_name.len,
			cstate->current_fh.fh_dentry->d_name.name);

	nfs4_lock_state();
	/* check close_lru for replay */
	if ((status = nfs4_preprocess_seqid_op(cstate,
					close->cl_seqid,
					&close->cl_stateid, 
					OPEN_STATE | CLOSE_STATE,
					&close->cl_stateowner, &stp, NULL)))
		goto out; 
	status = nfs_ok;
	update_stateid(&stp->st_stateid);
	memcpy(&close->cl_stateid, &stp->st_stateid, sizeof(stateid_t));

	/* release_stateid() calls nfsd_close() if needed */
	release_open_stateid(stp);

	/* place unused nfs4_stateowners on so_close_lru list to be
	 * released by the laundromat service after the lease period
	 * to enable us to handle CLOSE replay
	 */
	if (list_empty(&close->cl_stateowner->so_stateids))
		move_to_close_lru(close->cl_stateowner);
out:
	if (close->cl_stateowner) {
		nfs4_get_stateowner(close->cl_stateowner);
		cstate->replay_owner = close->cl_stateowner;
	}
	nfs4_unlock_state();
	return status;
}

__be32
nfsd4_delegreturn(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
		  struct nfsd4_delegreturn *dr)
{
	struct nfs4_delegation *dp;
	stateid_t *stateid = &dr->dr_stateid;
	struct inode *inode;
	__be32 status;
	int flags = 0;

	if ((status = fh_verify(rqstp, &cstate->current_fh, S_IFREG, 0)))
		return status;
	inode = cstate->current_fh.fh_dentry->d_inode;

	if (nfsd4_has_session(cstate))
		flags |= HAS_SESSION;
	nfs4_lock_state();
	status = nfserr_bad_stateid;
	if (ZERO_STATEID(stateid) || ONE_STATEID(stateid))
		goto out;
	status = nfserr_stale_stateid;
	if (STALE_STATEID(stateid))
		goto out;
	status = nfserr_bad_stateid;
	if (!is_delegation_stateid(stateid))
		goto out;
	dp = find_delegation_stateid(inode, stateid);
	if (!dp) {
		status = stateid_error_map(stateid);
		goto out;
	}
	status = check_stateid_generation(stateid, &dp->dl_stateid, flags);
	if (status)
		goto out;
	renew_client(dp->dl_client);

	unhash_delegation(dp);
out:
	nfs4_unlock_state();

	return status;
}


/* 
 * Lock owner state (byte-range locks)
 */
#define LOFF_OVERFLOW(start, len)      ((u64)(len) > ~(u64)(start))
#define LOCK_HASH_BITS              8
#define LOCK_HASH_SIZE             (1 << LOCK_HASH_BITS)
#define LOCK_HASH_MASK             (LOCK_HASH_SIZE - 1)

static inline u64
end_offset(u64 start, u64 len)
{
	u64 end;

	end = start + len;
	return end >= start ? end: NFS4_MAX_UINT64;
}

/* last octet in a range */
static inline u64
last_byte_offset(u64 start, u64 len)
{
	u64 end;

	BUG_ON(!len);
	end = start + len;
	return end > start ? end - 1: NFS4_MAX_UINT64;
}

#define lockownerid_hashval(id) \
        ((id) & LOCK_HASH_MASK)

static inline unsigned int
lock_ownerstr_hashval(struct inode *inode, u32 cl_id,
		struct xdr_netobj *ownername)
{
	return (file_hashval(inode) + cl_id
			+ opaque_hashval(ownername->data, ownername->len))
		& LOCK_HASH_MASK;
}

static struct list_head lock_ownerid_hashtbl[LOCK_HASH_SIZE];
static struct list_head	lock_ownerstr_hashtbl[LOCK_HASH_SIZE];
static struct list_head lockstateid_hashtbl[STATEID_HASH_SIZE];

static struct nfs4_stateid *
find_stateid(stateid_t *stid, int flags)
{
	struct nfs4_stateid *local;
	u32 st_id = stid->si_stateownerid;
	u32 f_id = stid->si_fileid;
	unsigned int hashval;

	dprintk("NFSD: find_stateid flags 0x%x\n",flags);
	if (flags & (LOCK_STATE | RD_STATE | WR_STATE)) {
		hashval = stateid_hashval(st_id, f_id);
		list_for_each_entry(local, &lockstateid_hashtbl[hashval], st_hash) {
			if ((local->st_stateid.si_stateownerid == st_id) &&
			    (local->st_stateid.si_fileid == f_id))
				return local;
		}
	} 

	if (flags & (OPEN_STATE | RD_STATE | WR_STATE)) {
		hashval = stateid_hashval(st_id, f_id);
		list_for_each_entry(local, &stateid_hashtbl[hashval], st_hash) {
			if ((local->st_stateid.si_stateownerid == st_id) &&
			    (local->st_stateid.si_fileid == f_id))
				return local;
		}
	}
	return NULL;
}

static struct nfs4_delegation *
find_delegation_stateid(struct inode *ino, stateid_t *stid)
{
	struct nfs4_file *fp;
	struct nfs4_delegation *dl;

	dprintk("NFSD: %s: stateid=" STATEID_FMT "\n", __func__,
		STATEID_VAL(stid));

	fp = find_file(ino);
	if (!fp)
		return NULL;
	dl = find_delegation_file(fp, stid);
	put_nfs4_file(fp);
	return dl;
}

/*
 * TODO: Linux file offsets are _signed_ 64-bit quantities, which means that
 * we can't properly handle lock requests that go beyond the (2^63 - 1)-th
 * byte, because of sign extension problems.  Since NFSv4 calls for 64-bit
 * locking, this prevents us from being completely protocol-compliant.  The
 * real solution to this problem is to start using unsigned file offsets in
 * the VFS, but this is a very deep change!
 */
static inline void
nfs4_transform_lock_offset(struct file_lock *lock)
{
	if (lock->fl_start < 0)
		lock->fl_start = OFFSET_MAX;
	if (lock->fl_end < 0)
		lock->fl_end = OFFSET_MAX;
}

/* Hack!: For now, we're defining this just so we can use a pointer to it
 * as a unique cookie to identify our (NFSv4's) posix locks. */
static const struct lock_manager_operations nfsd_posix_mng_ops  = {
};

static inline void
nfs4_set_lock_denied(struct file_lock *fl, struct nfsd4_lock_denied *deny)
{
	struct nfs4_stateowner *sop;
	unsigned int hval;

	if (fl->fl_lmops == &nfsd_posix_mng_ops) {
		sop = (struct nfs4_stateowner *) fl->fl_owner;
		hval = lockownerid_hashval(sop->so_id);
		kref_get(&sop->so_ref);
		deny->ld_sop = sop;
		deny->ld_clientid = sop->so_client->cl_clientid;
	} else {
		deny->ld_sop = NULL;
		deny->ld_clientid.cl_boot = 0;
		deny->ld_clientid.cl_id = 0;
	}
	deny->ld_start = fl->fl_start;
	deny->ld_length = NFS4_MAX_UINT64;
	if (fl->fl_end != NFS4_MAX_UINT64)
		deny->ld_length = fl->fl_end - fl->fl_start + 1;        
	deny->ld_type = NFS4_READ_LT;
	if (fl->fl_type != F_RDLCK)
		deny->ld_type = NFS4_WRITE_LT;
}

static struct nfs4_stateowner *
find_lockstateowner_str(struct inode *inode, clientid_t *clid,
		struct xdr_netobj *owner)
{
	unsigned int hashval = lock_ownerstr_hashval(inode, clid->cl_id, owner);
	struct nfs4_stateowner *op;

	list_for_each_entry(op, &lock_ownerstr_hashtbl[hashval], so_strhash) {
		if (same_owner_str(op, owner, clid))
			return op;
	}
	return NULL;
}

/*
 * Alloc a lock owner structure.
 * Called in nfsd4_lock - therefore, OPEN and OPEN_CONFIRM (if needed) has 
 * occured. 
 *
 * strhashval = lock_ownerstr_hashval 
 */

static struct nfs4_stateowner *
alloc_init_lock_stateowner(unsigned int strhashval, struct nfs4_client *clp, struct nfs4_stateid *open_stp, struct nfsd4_lock *lock) {
	struct nfs4_stateowner *sop;
	struct nfs4_replay *rp;
	unsigned int idhashval;

	if (!(sop = alloc_stateowner(&lock->lk_new_owner)))
		return NULL;
	idhashval = lockownerid_hashval(current_ownerid);
	INIT_LIST_HEAD(&sop->so_idhash);
	INIT_LIST_HEAD(&sop->so_strhash);
	INIT_LIST_HEAD(&sop->so_perclient);
	INIT_LIST_HEAD(&sop->so_stateids);
	INIT_LIST_HEAD(&sop->so_perstateid);
	INIT_LIST_HEAD(&sop->so_close_lru); /* not used */
	sop->so_time = 0;
	list_add(&sop->so_idhash, &lock_ownerid_hashtbl[idhashval]);
	list_add(&sop->so_strhash, &lock_ownerstr_hashtbl[strhashval]);
	list_add(&sop->so_perstateid, &open_stp->st_lockowners);
	sop->so_is_open_owner = 0;
	sop->so_id = current_ownerid++;
	sop->so_client = clp;
	/* It is the openowner seqid that will be incremented in encode in the
	 * case of new lockowners; so increment the lock seqid manually: */
	sop->so_seqid = lock->lk_new_lock_seqid + 1;
	sop->so_confirmed = 1;
	rp = &sop->so_replay;
	rp->rp_status = nfserr_serverfault;
	rp->rp_buflen = 0;
	rp->rp_buf = rp->rp_ibuf;
	return sop;
}

static struct nfs4_stateid *
alloc_init_lock_stateid(struct nfs4_stateowner *sop, struct nfs4_file *fp, struct nfs4_stateid *open_stp)
{
	struct nfs4_stateid *stp;
	unsigned int hashval = stateid_hashval(sop->so_id, fp->fi_id);

	stp = nfs4_alloc_stateid();
	if (stp == NULL)
		goto out;
	INIT_LIST_HEAD(&stp->st_hash);
	INIT_LIST_HEAD(&stp->st_perfile);
	INIT_LIST_HEAD(&stp->st_perstateowner);
	INIT_LIST_HEAD(&stp->st_lockowners); /* not used */
	list_add(&stp->st_hash, &lockstateid_hashtbl[hashval]);
	list_add(&stp->st_perfile, &fp->fi_stateids);
	list_add(&stp->st_perstateowner, &sop->so_stateids);
	stp->st_stateowner = sop;
	get_nfs4_file(fp);
	stp->st_file = fp;
	stp->st_stateid.si_boot = get_seconds();
	stp->st_stateid.si_stateownerid = sop->so_id;
	stp->st_stateid.si_fileid = fp->fi_id;
	stp->st_stateid.si_generation = 0;
	stp->st_vfs_file = open_stp->st_vfs_file; /* FIXME refcount?? */
	stp->st_access_bmap = open_stp->st_access_bmap;
	stp->st_deny_bmap = open_stp->st_deny_bmap;
	stp->st_openstp = open_stp;

out:
	return stp;
}

static int
check_lock_length(u64 offset, u64 length)
{
	return ((length == 0)  || ((length != NFS4_MAX_UINT64) &&
	     LOFF_OVERFLOW(offset, length)));
}

/*
 *  LOCK operation 
 */
__be32
nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	   struct nfsd4_lock *lock)
{
	struct nfs4_stateowner *open_sop = NULL;
	struct nfs4_stateowner *lock_sop = NULL;
	struct nfs4_stateid *lock_stp;
	struct file *filp;
	struct file_lock file_lock;
	struct file_lock conflock;
	__be32 status = 0;
	unsigned int strhashval;
	unsigned int cmd;
	int err;

	dprintk("NFSD: nfsd4_lock: start=%Ld length=%Ld\n",
		(long long) lock->lk_offset,
		(long long) lock->lk_length);

	if (check_lock_length(lock->lk_offset, lock->lk_length))
		 return nfserr_inval;

	if ((status = fh_verify(rqstp, &cstate->current_fh,
				S_IFREG, NFSD_MAY_LOCK))) {
		dprintk("NFSD: nfsd4_lock: permission denied!\n");
		return status;
	}

	nfs4_lock_state();

	if (lock->lk_is_new) {
		/*
		 * Client indicates that this is a new lockowner.
		 * Use open owner and open stateid to create lock owner and
		 * lock stateid.
		 */
		struct nfs4_stateid *open_stp = NULL;
		struct nfs4_file *fp;
		
		status = nfserr_stale_clientid;
		if (!nfsd4_has_session(cstate) &&
		    STALE_CLIENTID(&lock->lk_new_clientid))
			goto out;

		/* validate and update open stateid and open seqid */
		status = nfs4_preprocess_seqid_op(cstate,
				        lock->lk_new_open_seqid,
		                        &lock->lk_new_open_stateid,
					OPEN_STATE,
		                        &lock->lk_replay_owner, &open_stp,
					lock);
		if (status)
			goto out;
		open_sop = lock->lk_replay_owner;
		/* create lockowner and lock stateid */
		fp = open_stp->st_file;
		strhashval = lock_ownerstr_hashval(fp->fi_inode, 
				open_sop->so_client->cl_clientid.cl_id, 
				&lock->v.new.owner);
		/* XXX: Do we need to check for duplicate stateowners on
		 * the same file, or should they just be allowed (and
		 * create new stateids)? */
		status = nfserr_resource;
		lock_sop = alloc_init_lock_stateowner(strhashval,
				open_sop->so_client, open_stp, lock);
		if (lock_sop == NULL)
			goto out;
		lock_stp = alloc_init_lock_stateid(lock_sop, fp, open_stp);
		if (lock_stp == NULL)
			goto out;
	} else {
		/* lock (lock owner + lock stateid) already exists */
		status = nfs4_preprocess_seqid_op(cstate,
				       lock->lk_old_lock_seqid, 
				       &lock->lk_old_lock_stateid, 
				       LOCK_STATE,
				       &lock->lk_replay_owner, &lock_stp, lock);
		if (status)
			goto out;
		lock_sop = lock->lk_replay_owner;
	}
	/* lock->lk_replay_owner and lock_stp have been created or found */
	filp = lock_stp->st_vfs_file;

	status = nfserr_grace;
	if (locks_in_grace() && !lock->lk_reclaim)
		goto out;
	status = nfserr_no_grace;
	if (!locks_in_grace() && lock->lk_reclaim)
		goto out;

	locks_init_lock(&file_lock);
	switch (lock->lk_type) {
		case NFS4_READ_LT:
		case NFS4_READW_LT:
			file_lock.fl_type = F_RDLCK;
			cmd = F_SETLK;
		break;
		case NFS4_WRITE_LT:
		case NFS4_WRITEW_LT:
			file_lock.fl_type = F_WRLCK;
			cmd = F_SETLK;
		break;
		default:
			status = nfserr_inval;
		goto out;
	}
	file_lock.fl_owner = (fl_owner_t)lock_sop;
	file_lock.fl_pid = current->tgid;
	file_lock.fl_file = filp;
	file_lock.fl_flags = FL_POSIX;
	file_lock.fl_lmops = &nfsd_posix_mng_ops;

	file_lock.fl_start = lock->lk_offset;
	file_lock.fl_end = last_byte_offset(lock->lk_offset, lock->lk_length);
	nfs4_transform_lock_offset(&file_lock);

	/*
	* Try to lock the file in the VFS.
	* Note: locks.c uses the BKL to protect the inode's lock list.
	*/

	err = vfs_lock_file(filp, cmd, &file_lock, &conflock);
	switch (-err) {
	case 0: /* success! */
		update_stateid(&lock_stp->st_stateid);
		memcpy(&lock->lk_resp_stateid, &lock_stp->st_stateid, 
				sizeof(stateid_t));
		status = 0;
		break;
	case (EAGAIN):		/* conflock holds conflicting lock */
		status = nfserr_denied;
		dprintk("NFSD: nfsd4_lock: conflicting lock found!\n");
		nfs4_set_lock_denied(&conflock, &lock->lk_denied);
		break;
	case (EDEADLK):
		status = nfserr_deadlock;
		break;
	default:        
		dprintk("NFSD: nfsd4_lock: vfs_lock_file() failed! status %d\n",err);
		status = nfserr_resource;
		break;
	}
out:
	if (status && lock->lk_is_new && lock_sop)
		release_lockowner(lock_sop);
	if (lock->lk_replay_owner) {
		nfs4_get_stateowner(lock->lk_replay_owner);
		cstate->replay_owner = lock->lk_replay_owner;
	}
	nfs4_unlock_state();
	return status;
}

/*
 * The NFSv4 spec allows a client to do a LOCKT without holding an OPEN,
 * so we do a temporary open here just to get an open file to pass to
 * vfs_test_lock.  (Arguably perhaps test_lock should be done with an
 * inode operation.)
 */
static int nfsd_test_lock(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file_lock *lock)
{
	struct file *file;
	int err;

	err = nfsd_open(rqstp, fhp, S_IFREG, NFSD_MAY_READ, &file);
	if (err)
		return err;
	err = vfs_test_lock(file, lock);
	nfsd_close(file);
	return err;
}

/*
 * LOCKT operation
 */
__be32
nfsd4_lockt(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	    struct nfsd4_lockt *lockt)
{
	struct inode *inode;
	struct file_lock file_lock;
	int error;
	__be32 status;

	if (locks_in_grace())
		return nfserr_grace;

	if (check_lock_length(lockt->lt_offset, lockt->lt_length))
		 return nfserr_inval;

	lockt->lt_stateowner = NULL;
	nfs4_lock_state();

	status = nfserr_stale_clientid;
	if (!nfsd4_has_session(cstate) && STALE_CLIENTID(&lockt->lt_clientid))
		goto out;

	if ((status = fh_verify(rqstp, &cstate->current_fh, S_IFREG, 0))) {
		dprintk("NFSD: nfsd4_lockt: fh_verify() failed!\n");
		if (status == nfserr_symlink)
			status = nfserr_inval;
		goto out;
	}

	inode = cstate->current_fh.fh_dentry->d_inode;
	locks_init_lock(&file_lock);
	switch (lockt->lt_type) {
		case NFS4_READ_LT:
		case NFS4_READW_LT:
			file_lock.fl_type = F_RDLCK;
		break;
		case NFS4_WRITE_LT:
		case NFS4_WRITEW_LT:
			file_lock.fl_type = F_WRLCK;
		break;
		default:
			dprintk("NFSD: nfs4_lockt: bad lock type!\n");
			status = nfserr_inval;
		goto out;
	}

	lockt->lt_stateowner = find_lockstateowner_str(inode,
			&lockt->lt_clientid, &lockt->lt_owner);
	if (lockt->lt_stateowner)
		file_lock.fl_owner = (fl_owner_t)lockt->lt_stateowner;
	file_lock.fl_pid = current->tgid;
	file_lock.fl_flags = FL_POSIX;

	file_lock.fl_start = lockt->lt_offset;
	file_lock.fl_end = last_byte_offset(lockt->lt_offset, lockt->lt_length);

	nfs4_transform_lock_offset(&file_lock);

	status = nfs_ok;
	error = nfsd_test_lock(rqstp, &cstate->current_fh, &file_lock);
	if (error) {
		status = nfserrno(error);
		goto out;
	}
	if (file_lock.fl_type != F_UNLCK) {
		status = nfserr_denied;
		nfs4_set_lock_denied(&file_lock, &lockt->lt_denied);
	}
out:
	nfs4_unlock_state();
	return status;
}

__be32
nfsd4_locku(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
	    struct nfsd4_locku *locku)
{
	struct nfs4_stateid *stp;
	struct file *filp = NULL;
	struct file_lock file_lock;
	__be32 status;
	int err;
						        
	dprintk("NFSD: nfsd4_locku: start=%Ld length=%Ld\n",
		(long long) locku->lu_offset,
		(long long) locku->lu_length);

	if (check_lock_length(locku->lu_offset, locku->lu_length))
		 return nfserr_inval;

	nfs4_lock_state();
									        
	if ((status = nfs4_preprocess_seqid_op(cstate,
					locku->lu_seqid, 
					&locku->lu_stateid, 
					LOCK_STATE,
					&locku->lu_stateowner, &stp, NULL)))
		goto out;

	filp = stp->st_vfs_file;
	BUG_ON(!filp);
	locks_init_lock(&file_lock);
	file_lock.fl_type = F_UNLCK;
	file_lock.fl_owner = (fl_owner_t) locku->lu_stateowner;
	file_lock.fl_pid = current->tgid;
	file_lock.fl_file = filp;
	file_lock.fl_flags = FL_POSIX; 
	file_lock.fl_lmops = &nfsd_posix_mng_ops;
	file_lock.fl_start = locku->lu_offset;

	file_lock.fl_end = last_byte_offset(locku->lu_offset, locku->lu_length);
	nfs4_transform_lock_offset(&file_lock);

	/*
	*  Try to unlock the file in the VFS.
	*/
	err = vfs_lock_file(filp, F_SETLK, &file_lock, NULL);
	if (err) {
		dprintk("NFSD: nfs4_locku: vfs_lock_file failed!\n");
		goto out_nfserr;
	}
	/*
	* OK, unlock succeeded; the only thing left to do is update the stateid.
	*/
	update_stateid(&stp->st_stateid);
	memcpy(&locku->lu_stateid, &stp->st_stateid, sizeof(stateid_t));

out:
	if (locku->lu_stateowner) {
		nfs4_get_stateowner(locku->lu_stateowner);
		cstate->replay_owner = locku->lu_stateowner;
	}
	nfs4_unlock_state();
	return status;

out_nfserr:
	status = nfserrno(err);
	goto out;
}

/*
 * returns
 * 	1: locks held by lockowner
 * 	0: no locks held by lockowner
 */
static int
check_for_locks(struct file *filp, struct nfs4_stateowner *lowner)
{
	struct file_lock **flpp;
	struct inode *inode = filp->f_path.dentry->d_inode;
	int status = 0;

	lock_kernel();
	for (flpp = &inode->i_flock; *flpp != NULL; flpp = &(*flpp)->fl_next) {
		if ((*flpp)->fl_owner == (fl_owner_t)lowner) {
			status = 1;
			goto out;
		}
	}
out:
	unlock_kernel();
	return status;
}

__be32
nfsd4_release_lockowner(struct svc_rqst *rqstp,
			struct nfsd4_compound_state *cstate,
			struct nfsd4_release_lockowner *rlockowner)
{
	clientid_t *clid = &rlockowner->rl_clientid;
	struct nfs4_stateowner *sop;
	struct nfs4_stateid *stp;
	struct xdr_netobj *owner = &rlockowner->rl_owner;
	struct list_head matches;
	int i;
	__be32 status;

	dprintk("nfsd4_release_lockowner clientid: (%08x/%08x):\n",
		clid->cl_boot, clid->cl_id);

	/* XXX check for lease expiration */

	status = nfserr_stale_clientid;
	if (STALE_CLIENTID(clid))
		return status;

	nfs4_lock_state();

	status = nfserr_locks_held;
	/* XXX: we're doing a linear search through all the lockowners.
	 * Yipes!  For now we'll just hope clients aren't really using
	 * release_lockowner much, but eventually we have to fix these
	 * data structures. */
	INIT_LIST_HEAD(&matches);
	for (i = 0; i < LOCK_HASH_SIZE; i++) {
		list_for_each_entry(sop, &lock_ownerid_hashtbl[i], so_idhash) {
			if (!same_owner_str(sop, owner, clid))
				continue;
			list_for_each_entry(stp, &sop->so_stateids,
					st_perstateowner) {
				if (check_for_locks(stp->st_vfs_file, sop))
					goto out;
				/* Note: so_perclient unused for lockowners,
				 * so it's OK to fool with here. */
				list_add(&sop->so_perclient, &matches);
			}
		}
	}
	/* Clients probably won't expect us to return with some (but not all)
	 * of the lockowner state released; so don't release any until all
	 * have been checked. */
	status = nfs_ok;
	while (!list_empty(&matches)) {
		sop = list_entry(matches.next, struct nfs4_stateowner,
								so_perclient);
		/* unhash_stateowner deletes so_perclient only
		 * for openowners. */
		list_del(&sop->so_perclient);
		release_lockowner(sop);
	}
out:
	nfs4_unlock_state();
	return status;
}

static inline struct nfs4_client_reclaim *
alloc_reclaim(void)
{
	return kmalloc(sizeof(struct nfs4_client_reclaim), GFP_KERNEL);
}

int
nfs4_has_reclaimed_state(const char *name, bool use_exchange_id)
{
	unsigned int strhashval = clientstr_hashval(name);
	struct nfs4_client *clp;

	clp = find_confirmed_client_by_str(name, strhashval, use_exchange_id);
	return clp ? 1 : 0;
}

/*
 * failure => all reset bets are off, nfserr_no_grace...
 */
int
nfs4_client_to_reclaim(const char *name)
{
	unsigned int strhashval;
	struct nfs4_client_reclaim *crp = NULL;

	dprintk("NFSD nfs4_client_to_reclaim NAME: %.*s\n", HEXDIR_LEN, name);
	crp = alloc_reclaim();
	if (!crp)
		return 0;
	strhashval = clientstr_hashval(name);
	INIT_LIST_HEAD(&crp->cr_strhash);
	list_add(&crp->cr_strhash, &reclaim_str_hashtbl[strhashval]);
	memcpy(crp->cr_recdir, name, HEXDIR_LEN);
	reclaim_str_hashtbl_size++;
	return 1;
}

static void
nfs4_release_reclaim(void)
{
	struct nfs4_client_reclaim *crp = NULL;
	int i;

	for (i = 0; i < CLIENT_HASH_SIZE; i++) {
		while (!list_empty(&reclaim_str_hashtbl[i])) {
			crp = list_entry(reclaim_str_hashtbl[i].next,
			                struct nfs4_client_reclaim, cr_strhash);
			list_del(&crp->cr_strhash);
			kfree(crp);
			reclaim_str_hashtbl_size--;
		}
	}
	BUG_ON(reclaim_str_hashtbl_size);
}

/*
 * called from OPEN, CLAIM_PREVIOUS with a new clientid. */
static struct nfs4_client_reclaim *
nfs4_find_reclaim_client(clientid_t *clid)
{
	unsigned int strhashval;
	struct nfs4_client *clp;
	struct nfs4_client_reclaim *crp = NULL;


	/* find clientid in conf_id_hashtbl */
	clp = find_confirmed_client(clid);
	if (clp == NULL)
		return NULL;

	dprintk("NFSD: nfs4_find_reclaim_client for %.*s with recdir %s\n",
		            clp->cl_name.len, clp->cl_name.data,
			    clp->cl_recdir);

	/* find clp->cl_name in reclaim_str_hashtbl */
	strhashval = clientstr_hashval(clp->cl_recdir);
	list_for_each_entry(crp, &reclaim_str_hashtbl[strhashval], cr_strhash) {
		if (same_name(crp->cr_recdir, clp->cl_recdir)) {
			return crp;
		}
	}
	return NULL;
}

/*
* Called from OPEN. Look for clientid in reclaim list.
*/
__be32
nfs4_check_open_reclaim(clientid_t *clid)
{
	return nfs4_find_reclaim_client(clid) ? nfs_ok : nfserr_reclaim_bad;
}

/* initialization to perform at module load time: */

int
nfs4_state_init(void)
{
	int i, status;

	status = nfsd4_init_slabs();
	if (status)
		return status;
	for (i = 0; i < CLIENT_HASH_SIZE; i++) {
		INIT_LIST_HEAD(&conf_id_hashtbl[i]);
		INIT_LIST_HEAD(&conf_str_hashtbl[i]);
		INIT_LIST_HEAD(&unconf_str_hashtbl[i]);
		INIT_LIST_HEAD(&unconf_id_hashtbl[i]);
		INIT_LIST_HEAD(&reclaim_str_hashtbl[i]);
	}
	for (i = 0; i < SESSION_HASH_SIZE; i++)
		INIT_LIST_HEAD(&sessionid_hashtbl[i]);
	for (i = 0; i < FILE_HASH_SIZE; i++) {
		INIT_LIST_HEAD(&file_hashtbl[i]);
	}
	for (i = 0; i < OWNER_HASH_SIZE; i++) {
		INIT_LIST_HEAD(&ownerstr_hashtbl[i]);
		INIT_LIST_HEAD(&ownerid_hashtbl[i]);
	}
	for (i = 0; i < STATEID_HASH_SIZE; i++) {
		INIT_LIST_HEAD(&stateid_hashtbl[i]);
		INIT_LIST_HEAD(&lockstateid_hashtbl[i]);
	}
	for (i = 0; i < LOCK_HASH_SIZE; i++) {
		INIT_LIST_HEAD(&lock_ownerid_hashtbl[i]);
		INIT_LIST_HEAD(&lock_ownerstr_hashtbl[i]);
	}
	memset(&onestateid, ~0, sizeof(stateid_t));
	INIT_LIST_HEAD(&close_lru);
	INIT_LIST_HEAD(&client_lru);
	INIT_LIST_HEAD(&del_recall_lru);
	reclaim_str_hashtbl_size = 0;
	return 0;
}

static void
nfsd4_load_reboot_recovery_data(void)
{
	int status;

	nfs4_lock_state();
	nfsd4_init_recdir(user_recovery_dirname);
	status = nfsd4_recdir_load();
	nfs4_unlock_state();
	if (status)
		printk("NFSD: Failure reading reboot recovery data\n");
}

unsigned long
get_nfs4_grace_period(void)
{
	return max(user_lease_time, lease_time) * HZ;
}

/*
 * Since the lifetime of a delegation isn't limited to that of an open, a
 * client may quite reasonably hang on to a delegation as long as it has
 * the inode cached.  This becomes an obvious problem the first time a
 * client's inode cache approaches the size of the server's total memory.
 *
 * For now we avoid this problem by imposing a hard limit on the number
 * of delegations, which varies according to the server's memory size.
 */
static void
set_max_delegations(void)
{
	/*
	 * Allow at most 4 delegations per megabyte of RAM.  Quick
	 * estimates suggest that in the worst case (where every delegation
	 * is for a different inode), a delegation could take about 1.5K,
	 * giving a worst case usage of about 6% of memory.
	 */
	max_delegations = nr_free_buffer_pages() >> (20 - 2 - PAGE_SHIFT);
}

/* initialization to perform when the nfsd service is started: */

static int
__nfs4_state_start(void)
{
	unsigned long grace_time;

	boot_time = get_seconds();
	grace_time = get_nfs4_grace_period();
	lease_time = user_lease_time;
	locks_start_grace(&nfsd4_manager);
	printk(KERN_INFO "NFSD: starting %ld-second grace period\n",
	       grace_time/HZ);
	laundry_wq = create_singlethread_workqueue("nfsd4");
	if (laundry_wq == NULL)
		return -ENOMEM;
	queue_delayed_work(laundry_wq, &laundromat_work, grace_time);
	set_max_delegations();
	return set_callback_cred();
}

int
nfs4_state_start(void)
{
	int ret;

	if (nfs4_init)
		return 0;
	nfsd4_load_reboot_recovery_data();
	ret = __nfs4_state_start();
	if (ret)
		return ret;
	nfs4_init = 1;
	return 0;
}

time_t
nfs4_lease_time(void)
{
	return lease_time;
}

static void
__nfs4_state_shutdown(void)
{
	int i;
	struct nfs4_client *clp = NULL;
	struct nfs4_delegation *dp = NULL;
	struct list_head *pos, *next, reaplist;

	for (i = 0; i < CLIENT_HASH_SIZE; i++) {
		while (!list_empty(&conf_id_hashtbl[i])) {
			clp = list_entry(conf_id_hashtbl[i].next, struct nfs4_client, cl_idhash);
			expire_client(clp);
		}
		while (!list_empty(&unconf_str_hashtbl[i])) {
			clp = list_entry(unconf_str_hashtbl[i].next, struct nfs4_client, cl_strhash);
			expire_client(clp);
		}
	}
	INIT_LIST_HEAD(&reaplist);
	spin_lock(&recall_lock);
	list_for_each_safe(pos, next, &del_recall_lru) {
		dp = list_entry (pos, struct nfs4_delegation, dl_recall_lru);
		list_move(&dp->dl_recall_lru, &reaplist);
	}
	spin_unlock(&recall_lock);
	list_for_each_safe(pos, next, &reaplist) {
		dp = list_entry (pos, struct nfs4_delegation, dl_recall_lru);
		list_del_init(&dp->dl_recall_lru);
		unhash_delegation(dp);
	}

	nfsd4_shutdown_recdir();
	nfs4_init = 0;
}

void
nfs4_state_shutdown(void)
{
	cancel_rearming_delayed_workqueue(laundry_wq, &laundromat_work);
	destroy_workqueue(laundry_wq);
	locks_end_grace(&nfsd4_manager);
	nfs4_lock_state();
	nfs4_release_reclaim();
	__nfs4_state_shutdown();
	nfs4_unlock_state();
}

/*
 * user_recovery_dirname is protected by the nfsd_mutex since it's only
 * accessed when nfsd is starting.
 */
static void
nfs4_set_recdir(char *recdir)
{
	strcpy(user_recovery_dirname, recdir);
}

/*
 * Change the NFSv4 recovery directory to recdir.
 */
int
nfs4_reset_recoverydir(char *recdir)
{
	int status;
	struct path path;

	status = kern_path(recdir, LOOKUP_FOLLOW, &path);
	if (status)
		return status;
	status = -ENOTDIR;
	if (S_ISDIR(path.dentry->d_inode->i_mode)) {
		nfs4_set_recdir(recdir);
		status = 0;
	}
	path_put(&path);
	return status;
}

char *
nfs4_recoverydir(void)
{
	return user_recovery_dirname;
}

/*
 * Called when leasetime is changed.
 *
 * The only way the protocol gives us to handle on-the-fly lease changes is to
 * simulate a reboot.  Instead of doing that, we just wait till the next time
 * we start to register any changes in lease time.  If the administrator
 * really wants to change the lease time *now*, they can go ahead and bring
 * nfsd down and then back up again after changing the lease time.
 *
 * user_lease_time is protected by nfsd_mutex since it's only really accessed
 * when nfsd is starting
 */
void
nfs4_reset_lease(time_t leasetime)
{
	user_lease_time = leasetime;
}