summaryrefslogtreecommitdiffstats
path: root/fs/nfs/nfs3xdr.c
blob: 01c5e8b1941d2faea2732a181b1bec1fcdd85302 (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
/*
 * linux/fs/nfs/nfs3xdr.c
 *
 * XDR functions to encode/decode NFSv3 RPC arguments and results.
 *
 * Copyright (C) 1996, 1997 Olaf Kirch
 */

#include <linux/param.h>
#include <linux/time.h>
#include <linux/mm.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/in.h>
#include <linux/pagemap.h>
#include <linux/proc_fs.h>
#include <linux/kdev_t.h>
#include <linux/sunrpc/clnt.h>
#include <linux/nfs.h>
#include <linux/nfs3.h>
#include <linux/nfs_fs.h>
#include <linux/nfsacl.h>
#include "internal.h"

#define NFSDBG_FACILITY		NFSDBG_XDR

/* Mapping from NFS error code to "errno" error code. */
#define errno_NFSERR_IO		EIO

/*
 * Declare the space requirements for NFS arguments and replies as
 * number of 32bit-words
 */
#define NFS3_fhandle_sz		(1+16)
#define NFS3_fh_sz		(NFS3_fhandle_sz)	/* shorthand */
#define NFS3_sattr_sz		(15)
#define NFS3_filename_sz	(1+(NFS3_MAXNAMLEN>>2))
#define NFS3_path_sz		(1+(NFS3_MAXPATHLEN>>2))
#define NFS3_fattr_sz		(21)
#define NFS3_cookieverf_sz	(NFS3_COOKIEVERFSIZE>>2)
#define NFS3_wcc_attr_sz	(6)
#define NFS3_pre_op_attr_sz	(1+NFS3_wcc_attr_sz)
#define NFS3_post_op_attr_sz	(1+NFS3_fattr_sz)
#define NFS3_wcc_data_sz	(NFS3_pre_op_attr_sz+NFS3_post_op_attr_sz)
#define NFS3_diropargs_sz	(NFS3_fh_sz+NFS3_filename_sz)

#define NFS3_getattrargs_sz	(NFS3_fh_sz)
#define NFS3_setattrargs_sz	(NFS3_fh_sz+NFS3_sattr_sz+3)
#define NFS3_lookupargs_sz	(NFS3_fh_sz+NFS3_filename_sz)
#define NFS3_accessargs_sz	(NFS3_fh_sz+1)
#define NFS3_readlinkargs_sz	(NFS3_fh_sz)
#define NFS3_readargs_sz	(NFS3_fh_sz+3)
#define NFS3_writeargs_sz	(NFS3_fh_sz+5)
#define NFS3_createargs_sz	(NFS3_diropargs_sz+NFS3_sattr_sz)
#define NFS3_mkdirargs_sz	(NFS3_diropargs_sz+NFS3_sattr_sz)
#define NFS3_symlinkargs_sz	(NFS3_diropargs_sz+1+NFS3_sattr_sz)
#define NFS3_mknodargs_sz	(NFS3_diropargs_sz+2+NFS3_sattr_sz)
#define NFS3_removeargs_sz	(NFS3_fh_sz+NFS3_filename_sz)
#define NFS3_renameargs_sz	(NFS3_diropargs_sz+NFS3_diropargs_sz)
#define NFS3_linkargs_sz		(NFS3_fh_sz+NFS3_diropargs_sz)
#define NFS3_readdirargs_sz	(NFS3_fh_sz+NFS3_cookieverf_sz+3)
#define NFS3_readdirplusargs_sz	(NFS3_fh_sz+NFS3_cookieverf_sz+4)
#define NFS3_commitargs_sz	(NFS3_fh_sz+3)

#define NFS3_getattrres_sz	(1+NFS3_fattr_sz)
#define NFS3_setattrres_sz	(1+NFS3_wcc_data_sz)
#define NFS3_removeres_sz	(NFS3_setattrres_sz)
#define NFS3_lookupres_sz	(1+NFS3_fh_sz+(2 * NFS3_post_op_attr_sz))
#define NFS3_accessres_sz	(1+NFS3_post_op_attr_sz+1)
#define NFS3_readlinkres_sz	(1+NFS3_post_op_attr_sz+1)
#define NFS3_readres_sz		(1+NFS3_post_op_attr_sz+3)
#define NFS3_writeres_sz	(1+NFS3_wcc_data_sz+4)
#define NFS3_createres_sz	(1+NFS3_fh_sz+NFS3_post_op_attr_sz+NFS3_wcc_data_sz)
#define NFS3_renameres_sz	(1+(2 * NFS3_wcc_data_sz))
#define NFS3_linkres_sz		(1+NFS3_post_op_attr_sz+NFS3_wcc_data_sz)
#define NFS3_readdirres_sz	(1+NFS3_post_op_attr_sz+2)
#define NFS3_fsstatres_sz	(1+NFS3_post_op_attr_sz+13)
#define NFS3_fsinfores_sz	(1+NFS3_post_op_attr_sz+12)
#define NFS3_pathconfres_sz	(1+NFS3_post_op_attr_sz+6)
#define NFS3_commitres_sz	(1+NFS3_wcc_data_sz+2)

#define ACL3_getaclargs_sz	(NFS3_fh_sz+1)
#define ACL3_setaclargs_sz	(NFS3_fh_sz+1+ \
				XDR_QUADLEN(NFS_ACL_INLINE_BUFSIZE))
#define ACL3_getaclres_sz	(1+NFS3_post_op_attr_sz+1+ \
				XDR_QUADLEN(NFS_ACL_INLINE_BUFSIZE))
#define ACL3_setaclres_sz	(1+NFS3_post_op_attr_sz)

/*
 * Map file type to S_IFMT bits
 */
static const umode_t nfs_type2fmt[] = {
	[NF3BAD] = 0,
	[NF3REG] = S_IFREG,
	[NF3DIR] = S_IFDIR,
	[NF3BLK] = S_IFBLK,
	[NF3CHR] = S_IFCHR,
	[NF3LNK] = S_IFLNK,
	[NF3SOCK] = S_IFSOCK,
	[NF3FIFO] = S_IFIFO,
};

/*
 * While encoding arguments, set up the reply buffer in advance to
 * receive reply data directly into the page cache.
 */
static void prepare_reply_buffer(struct rpc_rqst *req, struct page **pages,
				 unsigned int base, unsigned int len,
				 unsigned int bufsize)
{
	struct rpc_auth	*auth = req->rq_cred->cr_auth;
	unsigned int replen;

	replen = RPC_REPHDRSIZE + auth->au_rslack + bufsize;
	xdr_inline_pages(&req->rq_rcv_buf, replen << 2, pages, base, len);
}

/*
 * Handle decode buffer overflows out-of-line.
 */
static void print_overflow_msg(const char *func, const struct xdr_stream *xdr)
{
	dprintk("NFS: %s prematurely hit the end of our receive buffer. "
		"Remaining buffer length is %tu words.\n",
		func, xdr->end - xdr->p);
}


/*
 * Encode/decode NFSv3 basic data types
 *
 * Basic NFSv3 data types are defined in section 2.5 of RFC 1813:
 * "NFS Version 3 Protocol Specification".
 *
 * Not all basic data types have their own encoding and decoding
 * functions.  For run-time efficiency, some data types are encoded
 * or decoded inline.
 */

static void encode_uint32(struct xdr_stream *xdr, u32 value)
{
	__be32 *p = xdr_reserve_space(xdr, 4);
	*p = cpu_to_be32(value);
}

static int decode_uint32(struct xdr_stream *xdr, u32 *value)
{
	__be32 *p;

	p = xdr_inline_decode(xdr, 4);
	if (unlikely(p == NULL))
		goto out_overflow;
	*value = be32_to_cpup(p);
	return 0;
out_overflow:
	print_overflow_msg(__func__, xdr);
	return -EIO;
}

static int decode_uint64(struct xdr_stream *xdr, u64 *value)
{
	__be32 *p;

	p = xdr_inline_decode(xdr, 8);
	if (unlikely(p == NULL))
		goto out_overflow;
	xdr_decode_hyper(p, value);
	return 0;
out_overflow:
	print_overflow_msg(__func__, xdr);
	return -EIO;
}

/*
 * fileid3
 *
 *	typedef uint64 fileid3;
 */
static __be32 *xdr_decode_fileid3(__be32 *p, u64 *fileid)
{
	return xdr_decode_hyper(p, fileid);
}

static int decode_fileid3(struct xdr_stream *xdr, u64 *fileid)
{
	return decode_uint64(xdr, fileid);
}

/*
 * filename3
 *
 *	typedef string filename3<>;
 */
static void encode_filename3(struct xdr_stream *xdr,
			     const char *name, u32 length)
{
	__be32 *p;

	BUG_ON(length > NFS3_MAXNAMLEN);
	p = xdr_reserve_space(xdr, 4 + length);
	xdr_encode_opaque(p, name, length);
}

static int decode_inline_filename3(struct xdr_stream *xdr,
				   const char **name, u32 *length)
{
	__be32 *p;
	u32 count;

	p = xdr_inline_decode(xdr, 4);
	if (unlikely(p == NULL))
		goto out_overflow;
	count = be32_to_cpup(p);
	if (count > NFS3_MAXNAMLEN)
		goto out_nametoolong;
	p = xdr_inline_decode(xdr, count);
	if (unlikely(p == NULL))
		goto out_overflow;
	*name = (const char *)p;
	*length = count;
	return 0;

out_nametoolong:
	dprintk("NFS: returned filename too long: %u\n", count);
	return -ENAMETOOLONG;
out_overflow:
	print_overflow_msg(__func__, xdr);
	return -EIO;
}

/*
 * nfspath3
 *
 *	typedef string nfspath3<>;
 */
static void encode_nfspath3(struct xdr_stream *xdr, struct page **pages,
			    const u32 length)
{
	BUG_ON(length > NFS3_MAXPATHLEN);
	encode_uint32(xdr, length);
	xdr_write_pages(xdr, pages, 0, length);
}

static int decode_nfspath3(struct xdr_stream *xdr)
{
	u32 recvd, count;
	size_t hdrlen;
	__be32 *p;

	p = xdr_inline_decode(xdr, 4);
	if (unlikely(p == NULL))
		goto out_overflow;
	count = be32_to_cpup(p);
	if (unlikely(count >= xdr->buf->page_len || count > NFS3_MAXPATHLEN))
		goto out_nametoolong;
	hdrlen = (u8 *)xdr->p - (u8 *)xdr->iov->iov_base;
	recvd = xdr->buf->len - hdrlen;
	if (unlikely(count > recvd))
		goto out_cheating;

	xdr_read_pages(xdr, count);
	xdr_terminate_string(xdr->buf, count);
	return 0;

out_nametoolong:
	dprintk("NFS: returned pathname too long: %u\n", count);
	return -ENAMETOOLONG;
out_cheating:
	dprintk("NFS: server cheating in pathname result: "
		"count %u > recvd %u\n", count, recvd);
	return -EIO;
out_overflow:
	print_overflow_msg(__func__, xdr);
	return -EIO;
}

/*
 * cookie3
 *
 *	typedef uint64 cookie3
 */
static __be32 *xdr_encode_cookie3(__be32 *p, u64 cookie)
{
	return xdr_encode_hyper(p, cookie);
}

static int decode_cookie3(struct xdr_stream *xdr, u64 *cookie)
{
	return decode_uint64(xdr, cookie);
}

/*
 * cookieverf3
 *
 *	typedef opaque cookieverf3[NFS3_COOKIEVERFSIZE];
 */
static __be32 *xdr_encode_cookieverf3(__be32 *p, const __be32 *verifier)
{
	memcpy(p, verifier, NFS3_COOKIEVERFSIZE);
	return p + XDR_QUADLEN(NFS3_COOKIEVERFSIZE);
}

static int decode_cookieverf3(struct xdr_stream *xdr, __be32 *verifier)
{
	__be32 *p;

	p = xdr_inline_decode(xdr, NFS3_COOKIEVERFSIZE);
	if (unlikely(p == NULL))
		goto out_overflow;
	memcpy(verifier, p, NFS3_COOKIEVERFSIZE);
	return 0;
out_overflow:
	print_overflow_msg(__func__, xdr);
	return -EIO;
}

/*
 * createverf3
 *
 *	typedef opaque createverf3[NFS3_CREATEVERFSIZE];
 */
static void encode_createverf3(struct xdr_stream *xdr, const __be32 *verifier)
{
	__be32 *p;

	p = xdr_reserve_space(xdr, NFS3_CREATEVERFSIZE);
	memcpy(p, verifier, NFS3_CREATEVERFSIZE);
}

static int decode_writeverf3(struct xdr_stream *xdr, __be32 *verifier)
{
	__be32 *p;

	p = xdr_inline_decode(xdr, NFS3_WRITEVERFSIZE);
	if (unlikely(p == NULL))
		goto out_overflow;
	memcpy(verifier, p, NFS3_WRITEVERFSIZE);
	return 0;
out_overflow:
	print_overflow_msg(__func__, xdr);
	return -EIO;
}

/*
 * size3
 *
 *	typedef uint64 size3;
 */
static __be32 *xdr_decode_size3(__be32 *p, u64 *size)
{
	return xdr_decode_hyper(p, size);
}

/*
 * nfsstat3
 *
 *	enum nfsstat3 {
 *		NFS3_OK = 0,
 *		...
 *	}
 */
#define NFS3_OK		NFS_OK

static int decode_nfsstat3(struct xdr_stream *xdr, enum nfs_stat *status)
{
	__be32 *p;

	p = xdr_inline_decode(xdr, 4);
	if (unlikely(p == NULL))
		goto out_overflow;
	*status = be32_to_cpup(p);
	return 0;
out_overflow:
	print_overflow_msg(__func__, xdr);
	return -EIO;
}

/*
 * ftype3
 *
 *	enum ftype3 {
 *		NF3REG	= 1,
 *		NF3DIR	= 2,
 *		NF3BLK	= 3,
 *		NF3CHR	= 4,
 *		NF3LNK	= 5,
 *		NF3SOCK	= 6,
 *		NF3FIFO	= 7
 *	};
 */
static void encode_ftype3(struct xdr_stream *xdr, const u32 type)
{
	BUG_ON(type > NF3FIFO);
	encode_uint32(xdr, type);
}

static __be32 *xdr_decode_ftype3(__be32 *p, umode_t *mode)
{
	u32 type;

	type = be32_to_cpup(p++);
	if (type > NF3FIFO)
		type = NF3NON;
	*mode = nfs_type2fmt[type];
	return p;
}

/*
 * specdata3
 *
 *     struct specdata3 {
 *             uint32  specdata1;
 *             uint32  specdata2;
 *     };
 */
static void encode_specdata3(struct xdr_stream *xdr, const dev_t rdev)
{
	__be32 *p;

	p = xdr_reserve_space(xdr, 8);
	*p++ = cpu_to_be32(MAJOR(rdev));
	*p = cpu_to_be32(MINOR(rdev));
}

static __be32 *xdr_decode_specdata3(__be32 *p, dev_t *rdev)
{
	unsigned int major, minor;

	major = be32_to_cpup(p++);
	minor = be32_to_cpup(p++);
	*rdev = MKDEV(major, minor);
	if (MAJOR(*rdev) != major || MINOR(*rdev) != minor)
		*rdev = 0;
	return p;
}

/*
 * nfs_fh3
 *
 *	struct nfs_fh3 {
 *		opaque       data<NFS3_FHSIZE>;
 *	};
 */
static void encode_nfs_fh3(struct xdr_stream *xdr, const struct nfs_fh *fh)
{
	__be32 *p;

	BUG_ON(fh->size > NFS3_FHSIZE);
	p = xdr_reserve_space(xdr, 4 + fh->size);
	xdr_encode_opaque(p, fh->data, fh->size);
}

static int decode_nfs_fh3(struct xdr_stream *xdr, struct nfs_fh *fh)
{
	u32 length;
	__be32 *p;

	p = xdr_inline_decode(xdr, 4);
	if (unlikely(p == NULL))
		goto out_overflow;
	length = be32_to_cpup(p++);
	if (unlikely(length > NFS3_FHSIZE))
		goto out_toobig;
	p = xdr_inline_decode(xdr, length);
	if (unlikely(p == NULL))
		goto out_overflow;
	fh->size = length;
	memcpy(fh->data, p, length);
	return 0;
out_toobig:
	dprintk("NFS: file handle size (%u) too big\n", length);
	return -E2BIG;
out_overflow:
	print_overflow_msg(__func__, xdr);
	return -EIO;
}

static void zero_nfs_fh3(struct nfs_fh *fh)
{
	memset(fh, 0, sizeof(*fh));
}

/*
 * nfstime3
 *
 *	struct nfstime3 {
 *		uint32	seconds;
 *		uint32	nseconds;
 *	};
 */
static __be32 *xdr_encode_nfstime3(__be32 *p, const struct timespec *timep)
{
	*p++ = cpu_to_be32(timep->tv_sec);
	*p++ = cpu_to_be32(timep->tv_nsec);
	return p;
}

static __be32 *xdr_decode_nfstime3(__be32 *p, struct timespec *timep)
{
	timep->tv_sec = be32_to_cpup(p++);
	timep->tv_nsec = be32_to_cpup(p++);
	return p;
}

/*
 * sattr3
 *
 *	enum time_how {
 *		DONT_CHANGE		= 0,
 *		SET_TO_SERVER_TIME	= 1,
 *		SET_TO_CLIENT_TIME	= 2
 *	};
 *
 *	union set_mode3 switch (bool set_it) {
 *	case TRUE:
 *		mode3	mode;
 *	default:
 *		void;
 *	};
 *
 *	union set_uid3 switch (bool set_it) {
 *	case TRUE:
 *		uid3	uid;
 *	default:
 *		void;
 *	};
 *
 *	union set_gid3 switch (bool set_it) {
 *	case TRUE:
 *		gid3	gid;
 *	default:
 *		void;
 *	};
 *
 *	union set_size3 switch (bool set_it) {
 *	case TRUE:
 *		size3	size;
 *	default:
 *		void;
 *	};
 *
 *	union set_atime switch (time_how set_it) {
 *	case SET_TO_CLIENT_TIME:
 *		nfstime3	atime;
 *	default:
 *		void;
 *	};
 *
 *	union set_mtime switch (time_how set_it) {
 *	case SET_TO_CLIENT_TIME:
 *		nfstime3  mtime;
 *	default:
 *		void;
 *	};
 *
 *	struct sattr3 {
 *		set_mode3	mode;
 *		set_uid3	uid;
 *		set_gid3	gid;
 *		set_size3	size;
 *		set_atime	atime;
 *		set_mtime	mtime;
 *	};
 */
static void encode_sattr3(struct xdr_stream *xdr, const struct iattr *attr)
{
	u32 nbytes;
	__be32 *p;

	/*
	 * In order to make only a single xdr_reserve_space() call,
	 * pre-compute the total number of bytes to be reserved.
	 * Six boolean values, one for each set_foo field, are always
	 * present in the encoded result, so start there.
	 */
	nbytes = 6 * 4;
	if (attr->ia_valid & ATTR_MODE)
		nbytes += 4;
	if (attr->ia_valid & ATTR_UID)
		nbytes += 4;
	if (attr->ia_valid & ATTR_GID)
		nbytes += 4;
	if (attr->ia_valid & ATTR_SIZE)
		nbytes += 8;
	if (attr->ia_valid & ATTR_ATIME_SET)
		nbytes += 8;
	if (attr->ia_valid & ATTR_MTIME_SET)
		nbytes += 8;
	p = xdr_reserve_space(xdr, nbytes);

	if (attr->ia_valid & ATTR_MODE) {
		*p++ = xdr_one;
		*p++ = cpu_to_be32(attr->ia_mode & S_IALLUGO);
	} else
		*p++ = xdr_zero;

	if (attr->ia_valid & ATTR_UID) {
		*p++ = xdr_one;
		*p++ = cpu_to_be32(attr->ia_uid);
	} else
		*p++ = xdr_zero;

	if (attr->ia_valid & ATTR_GID) {
		*p++ = xdr_one;
		*p++ = cpu_to_be32(attr->ia_gid);
	} else
		*p++ = xdr_zero;

	if (attr->ia_valid & ATTR_SIZE) {
		*p++ = xdr_one;
		p = xdr_encode_hyper(p, (u64)attr->ia_size);
	} else
		*p++ = xdr_zero;

	if (attr->ia_valid & ATTR_ATIME_SET) {
		*p++ = xdr_two;
		p = xdr_encode_nfstime3(p, &attr->ia_atime);
	} else if (attr->ia_valid & ATTR_ATIME) {
		*p++ = xdr_one;
	} else
		*p++ = xdr_zero;

	if (attr->ia_valid & ATTR_MTIME_SET) {
		*p++ = xdr_two;
		xdr_encode_nfstime3(p, &attr->ia_mtime);
	} else if (attr->ia_valid & ATTR_MTIME) {
		*p = xdr_one;
	} else
		*p = xdr_zero;
}

/*
 * fattr3
 *
 *	struct fattr3 {
 *		ftype3		type;
 *		mode3		mode;
 *		uint32		nlink;
 *		uid3		uid;
 *		gid3		gid;
 *		size3		size;
 *		size3		used;
 *		specdata3	rdev;
 *		uint64		fsid;
 *		fileid3		fileid;
 *		nfstime3	atime;
 *		nfstime3	mtime;
 *		nfstime3	ctime;
 *	};
 */
static int decode_fattr3(struct xdr_stream *xdr, struct nfs_fattr *fattr)
{
	umode_t fmode;
	__be32 *p;

	p = xdr_inline_decode(xdr, NFS3_fattr_sz << 2);
	if (unlikely(p == NULL))
		goto out_overflow;

	p = xdr_decode_ftype3(p, &fmode);

	fattr->mode = (be32_to_cpup(p++) & ~S_IFMT) | fmode;
	fattr->nlink = be32_to_cpup(p++);
	fattr->uid = be32_to_cpup(p++);
	fattr->gid = be32_to_cpup(p++);

	p = xdr_decode_size3(p, &fattr->size);
	p = xdr_decode_size3(p, &fattr->du.nfs3.used);
	p = xdr_decode_specdata3(p, &fattr->rdev);

	p = xdr_decode_hyper(p, &fattr->fsid.major);
	fattr->fsid.minor = 0;

	p = xdr_decode_fileid3(p, &fattr->fileid);
	p = xdr_decode_nfstime3(p, &fattr->atime);
	p = xdr_decode_nfstime3(p, &fattr->mtime);
	xdr_decode_nfstime3(p, &fattr->ctime);

	fattr->valid |= NFS_ATTR_FATTR_V3;
	return 0;
out_overflow:
	print_overflow_msg(__func__, xdr);
	return -EIO;
}

/*
 * post_op_attr
 *
 *	union post_op_attr switch (bool attributes_follow) {
 *	case TRUE:
 *		fattr3	attributes;
 *	case FALSE:
 *		void;
 *	};
 */
static int decode_post_op_attr(struct xdr_stream *xdr, struct nfs_fattr *fattr)
{
	__be32 *p;

	p = xdr_inline_decode(xdr, 4);
	if (unlikely(p == NULL))
		goto out_overflow;
	if (*p != xdr_zero)
		return decode_fattr3(xdr, fattr);
	return 0;
out_overflow:
	print_overflow_msg(__func__, xdr);
	return -EIO;
}

/*
 * wcc_attr
 *	struct wcc_attr {
 *		size3		size;
 *		nfstime3	mtime;
 *		nfstime3	ctime;
 *	};
 */
static int decode_wcc_attr(struct xdr_stream *xdr, struct nfs_fattr *fattr)
{
	__be32 *p;

	p = xdr_inline_decode(xdr, NFS3_wcc_attr_sz << 2);
	if (unlikely(p == NULL))
		goto out_overflow;

	fattr->valid |= NFS_ATTR_FATTR_PRESIZE
		| NFS_ATTR_FATTR_PREMTIME
		| NFS_ATTR_FATTR_PRECTIME;

	p = xdr_decode_size3(p, &fattr->pre_size);
	p = xdr_decode_nfstime3(p, &fattr->pre_mtime);
	xdr_decode_nfstime3(p, &fattr->pre_ctime);

	return 0;
out_overflow:
	print_overflow_msg(__func__, xdr);
	return -EIO;
}

/*
 * pre_op_attr
 *	union pre_op_attr switch (bool attributes_follow) {
 *	case TRUE:
 *		wcc_attr	attributes;
 *	case FALSE:
 *		void;
 *	};
 *
 * wcc_data
 *
 *	struct wcc_data {
 *		pre_op_attr	before;
 *		post_op_attr	after;
 *	};
 */
static int decode_pre_op_attr(struct xdr_stream *xdr, struct nfs_fattr *fattr)
{
	__be32 *p;

	p = xdr_inline_decode(xdr, 4);
	if (unlikely(p == NULL))
		goto out_overflow;
	if (*p != xdr_zero)
		return decode_wcc_attr(xdr, fattr);
	return 0;
out_overflow:
	print_overflow_msg(__func__, xdr);
	return -EIO;
}

static int decode_wcc_data(struct xdr_stream *xdr, struct nfs_fattr *fattr)
{
	int error;

	error = decode_pre_op_attr(xdr, fattr);
	if (unlikely(error))
		goto out;
	error = decode_post_op_attr(xdr, fattr);
out:
	return error;
}

/*
 * post_op_fh3
 *
 *	union post_op_fh3 switch (bool handle_follows) {
 *	case TRUE:
 *		nfs_fh3  handle;
 *	case FALSE:
 *		void;
 *	};
 */
static int decode_post_op_fh3(struct xdr_stream *xdr, struct nfs_fh *fh)
{
	__be32 *p = xdr_inline_decode(xdr, 4);
	if (unlikely(p == NULL))
		goto out_overflow;
	if (*p != xdr_zero)
		return decode_nfs_fh3(xdr, fh);
	zero_nfs_fh3(fh);
	return 0;
out_overflow:
	print_overflow_msg(__func__, xdr);
	return -EIO;
}

/*
 * diropargs3
 *
 *	struct diropargs3 {
 *		nfs_fh3		dir;
 *		filename3	name;
 *	};
 */
static void encode_diropargs3(struct xdr_stream *xdr, const struct nfs_fh *fh,
			      const char *name, u32 length)
{
	encode_nfs_fh3(xdr, fh);
	encode_filename3(xdr, name, length);
}


/*
 * NFSv3 XDR encode functions
 *
 * NFSv3 argument types are defined in section 3.3 of RFC 1813:
 * "NFS Version 3 Protocol Specification".
 */

/*
 * 3.3.1  GETATTR3args
 *
 *	struct GETATTR3args {
 *		nfs_fh3  object;
 *	};
 */
static void nfs3_xdr_enc_getattr3args(struct rpc_rqst *req,
				      struct xdr_stream *xdr,
				      const struct nfs_fh *fh)
{
	encode_nfs_fh3(xdr, fh);
}

/*
 * 3.3.2  SETATTR3args
 *
 *	union sattrguard3 switch (bool check) {
 *	case TRUE:
 *		nfstime3  obj_ctime;
 *	case FALSE:
 *		void;
 *	};
 *
 *	struct SETATTR3args {
 *		nfs_fh3		object;
 *		sattr3		new_attributes;
 *		sattrguard3	guard;
 *	};
 */
static void encode_sattrguard3(struct xdr_stream *xdr,
			       const struct nfs3_sattrargs *args)
{
	__be32 *p;

	if (args->guard) {
		p = xdr_reserve_space(xdr, 4 + 8);
		*p++ = xdr_one;
		xdr_encode_nfstime3(p, &args->guardtime);
	} else {
		p = xdr_reserve_space(xdr, 4);
		*p = xdr_zero;
	}
}

static void nfs3_xdr_enc_setattr3args(struct rpc_rqst *req,
				      struct xdr_stream *xdr,
				      const struct nfs3_sattrargs *args)
{
	encode_nfs_fh3(xdr, args->fh);
	encode_sattr3(xdr, args->sattr);
	encode_sattrguard3(xdr, args);
}

/*
 * 3.3.3  LOOKUP3args
 *
 *	struct LOOKUP3args {
 *		diropargs3  what;
 *	};
 */
static void nfs3_xdr_enc_lookup3args(struct rpc_rqst *req,
				     struct xdr_stream *xdr,
				     const struct nfs3_diropargs *args)
{
	encode_diropargs3(xdr, args->fh, args->name, args->len);
}

/*
 * 3.3.4  ACCESS3args
 *
 *	struct ACCESS3args {
 *		nfs_fh3		object;
 *		uint32		access;
 *	};
 */
static void encode_access3args(struct xdr_stream *xdr,
			       const struct nfs3_accessargs *args)
{
	encode_nfs_fh3(xdr, args->fh);
	encode_uint32(xdr, args->access);
}

static void nfs3_xdr_enc_access3args(struct rpc_rqst *req,
				     struct xdr_stream *xdr,
				     const struct nfs3_accessargs *args)
{
	encode_access3args(xdr, args);
}

/*
 * 3.3.5  READLINK3args
 *
 *	struct READLINK3args {
 *		nfs_fh3	symlink;
 *	};
 */
static void nfs3_xdr_enc_readlink3args(struct rpc_rqst *req,
				       struct xdr_stream *xdr,
				       const struct nfs3_readlinkargs *args)
{
	encode_nfs_fh3(xdr, args->fh);
	prepare_reply_buffer(req, args->pages, args->pgbase,
					args->pglen, NFS3_readlinkres_sz);
}

/*
 * 3.3.6  READ3args
 *
 *	struct READ3args {
 *		nfs_fh3		file;
 *		offset3		offset;
 *		count3		count;
 *	};
 */
static void encode_read3args(struct xdr_stream *xdr,
			     const struct nfs_readargs *args)
{
	__be32 *p;

	encode_nfs_fh3(xdr, args->fh);

	p = xdr_reserve_space(xdr, 8 + 4);
	p = xdr_encode_hyper(p, args->offset);
	*p = cpu_to_be32(args->count);
}

static void nfs3_xdr_enc_read3args(struct rpc_rqst *req,
				   struct xdr_stream *xdr,
				   const struct nfs_readargs *args)
{
	encode_read3args(xdr, args);
	prepare_reply_buffer(req, args->pages, args->pgbase,
					args->count, NFS3_readres_sz);
	req->rq_rcv_buf.flags |= XDRBUF_READ;
}

/*
 * 3.3.7  WRITE3args
 *
 *	enum stable_how {
 *		UNSTABLE  = 0,
 *		DATA_SYNC = 1,
 *		FILE_SYNC = 2
 *	};
 *
 *	struct WRITE3args {
 *		nfs_fh3		file;
 *		offset3		offset;
 *		count3		count;
 *		stable_how	stable;
 *		opaque		data<>;
 *	};
 */
static void encode_write3args(struct xdr_stream *xdr,
			      const struct nfs_writeargs *args)
{
	__be32 *p;

	encode_nfs_fh3(xdr, args->fh);

	p = xdr_reserve_space(xdr, 8 + 4 + 4 + 4);
	p = xdr_encode_hyper(p, args->offset);
	*p++ = cpu_to_be32(args->count);
	*p++ = cpu_to_be32(args->stable);
	*p = cpu_to_be32(args->count);
	xdr_write_pages(xdr, args->pages, args->pgbase, args->count);
}

static void nfs3_xdr_enc_write3args(struct rpc_rqst *req,
				    struct xdr_stream *xdr,
				    const struct nfs_writeargs *args)
{
	encode_write3args(xdr, args);
	xdr->buf->flags |= XDRBUF_WRITE;
}

/*
 * 3.3.8  CREATE3args
 *
 *	enum createmode3 {
 *		UNCHECKED = 0,
 *		GUARDED   = 1,
 *		EXCLUSIVE = 2
 *	};
 *
 *	union createhow3 switch (createmode3 mode) {
 *	case UNCHECKED:
 *	case GUARDED:
 *		sattr3       obj_attributes;
 *	case EXCLUSIVE:
 *		createverf3  verf;
 *	};
 *
 *	struct CREATE3args {
 *		diropargs3	where;
 *		createhow3	how;
 *	};
 */
static void encode_createhow3(struct xdr_stream *xdr,
			      const struct nfs3_createargs *args)
{
	encode_uint32(xdr, args->createmode);
	switch (args->createmode) {
	case NFS3_CREATE_UNCHECKED:
	case NFS3_CREATE_GUARDED:
		encode_sattr3(xdr, args->sattr);
		break;
	case NFS3_CREATE_EXCLUSIVE:
		encode_createverf3(xdr, args->verifier);
		break;
	default:
		BUG();
	}
}

static void nfs3_xdr_enc_create3args(struct rpc_rqst *req,
				     struct xdr_stream *xdr,
				     const struct nfs3_createargs *args)
{
	encode_diropargs3(xdr, args->fh, args->name, args->len);
	encode_createhow3(xdr, args);
}

/*
 * 3.3.9  MKDIR3args
 *
 *	struct MKDIR3args {
 *		diropargs3	where;
 *		sattr3		attributes;
 *	};
 */
static void nfs3_xdr_enc_mkdir3args(struct rpc_rqst *req,
				    struct xdr_stream *xdr,
				    const struct nfs3_mkdirargs *args)
{
	encode_diropargs3(xdr, args->fh, args->name, args->len);
	encode_sattr3(xdr, args->sattr);
}

/*
 * 3.3.10  SYMLINK3args
 *
 *	struct symlinkdata3 {
 *		sattr3		symlink_attributes;
 *		nfspath3	symlink_data;
 *	};
 *
 *	struct SYMLINK3args {
 *		diropargs3	where;
 *		symlinkdata3	symlink;
 *	};
 */
static void encode_symlinkdata3(struct xdr_stream *xdr,
				const struct nfs3_symlinkargs *args)
{
	encode_sattr3(xdr, args->sattr);
	encode_nfspath3(xdr, args->pages, args->pathlen);
}

static void nfs3_xdr_enc_symlink3args(struct rpc_rqst *req,
				      struct xdr_stream *xdr,
				      const struct nfs3_symlinkargs *args)
{
	encode_diropargs3(xdr, args->fromfh, args->fromname, args->fromlen);
	encode_symlinkdata3(xdr, args);
}

/*
 * 3.3.11  MKNOD3args
 *
 *	struct devicedata3 {
 *		sattr3		dev_attributes;
 *		specdata3	spec;
 *	};
 *
 *	union mknoddata3 switch (ftype3 type) {
 *	case NF3CHR:
 *	case NF3BLK:
 *		devicedata3	device;
 *	case NF3SOCK:
 *	case NF3FIFO:
 *		sattr3		pipe_attributes;
 *	default:
 *		void;
 *	};
 *
 *	struct MKNOD3args {
 *		diropargs3	where;
 *		mknoddata3	what;
 *	};
 */
static void encode_devicedata3(struct xdr_stream *xdr,
			       const struct nfs3_mknodargs *args)
{
	encode_sattr3(xdr, args->sattr);
	encode_specdata3(xdr, args->rdev);
}

static void encode_mknoddata3(struct xdr_stream *xdr,
			      const struct nfs3_mknodargs *args)
{
	encode_ftype3(xdr, args->type);
	switch (args->type) {
	case NF3CHR:
	case NF3BLK:
		encode_devicedata3(xdr, args);
		break;
	case NF3SOCK:
	case NF3FIFO:
		encode_sattr3(xdr, args->sattr);
		break;
	case NF3REG:
	case NF3DIR:
		break;
	default:
		BUG();
	}
}

static void nfs3_xdr_enc_mknod3args(struct rpc_rqst *req,
				    struct xdr_stream *xdr,
				    const struct nfs3_mknodargs *args)
{
	encode_diropargs3(xdr, args->fh, args->name, args->len);
	encode_mknoddata3(xdr, args);
}

/*
 * 3.3.12  REMOVE3args
 *
 *	struct REMOVE3args {
 *		diropargs3  object;
 *	};
 */
static void nfs3_xdr_enc_remove3args(struct rpc_rqst *req,
				     struct xdr_stream *xdr,
				     const struct nfs_removeargs *args)
{
	encode_diropargs3(xdr, args->fh, args->name.name, args->name.len);
}

/*
 * 3.3.14  RENAME3args
 *
 *	struct RENAME3args {
 *		diropargs3	from;
 *		diropargs3	to;
 *	};
 */
static void nfs3_xdr_enc_rename3args(struct rpc_rqst *req,
				     struct xdr_stream *xdr,
				     const struct nfs_renameargs *args)
{
	const struct qstr *old = args->old_name;
	const struct qstr *new = args->new_name;

	encode_diropargs3(xdr, args->old_dir, old->name, old->len);
	encode_diropargs3(xdr, args->new_dir, new->name, new->len);
}

/*
 * 3.3.15  LINK3args
 *
 *	struct LINK3args {
 *		nfs_fh3		file;
 *		diropargs3	link;
 *	};
 */
static void nfs3_xdr_enc_link3args(struct rpc_rqst *req,
				   struct xdr_stream *xdr,
				   const struct nfs3_linkargs *args)
{
	encode_nfs_fh3(xdr, args->fromfh);
	encode_diropargs3(xdr, args->tofh, args->toname, args->tolen);
}

/*
 * 3.3.16  READDIR3args
 *
 *	struct READDIR3args {
 *		nfs_fh3		dir;
 *		cookie3		cookie;
 *		cookieverf3	cookieverf;
 *		count3		count;
 *	};
 */
static void encode_readdir3args(struct xdr_stream *xdr,
				const struct nfs3_readdirargs *args)
{
	__be32 *p;

	encode_nfs_fh3(xdr, args->fh);

	p = xdr_reserve_space(xdr, 8 + NFS3_COOKIEVERFSIZE + 4);
	p = xdr_encode_cookie3(p, args->cookie);
	p = xdr_encode_cookieverf3(p, args->verf);
	*p = cpu_to_be32(args->count);
}

static void nfs3_xdr_enc_readdir3args(struct rpc_rqst *req,
				      struct xdr_stream *xdr,
				      const struct nfs3_readdirargs *args)
{
	encode_readdir3args(xdr, args);
	prepare_reply_buffer(req, args->pages, 0,
				args->count, NFS3_readdirres_sz);
}

/*
 * 3.3.17  READDIRPLUS3args
 *
 *	struct READDIRPLUS3args {
 *		nfs_fh3		dir;
 *		cookie3		cookie;
 *		cookieverf3	cookieverf;
 *		count3		dircount;
 *		count3		maxcount;
 *	};
 */
static void encode_readdirplus3args(struct xdr_stream *xdr,
				    const struct nfs3_readdirargs *args)
{
	__be32 *p;

	encode_nfs_fh3(xdr, args->fh);

	p = xdr_reserve_space(xdr, 8 + NFS3_COOKIEVERFSIZE + 4 + 4);
	p = xdr_encode_cookie3(p, args->cookie);
	p = xdr_encode_cookieverf3(p, args->verf);

	/*
	 * readdirplus: need dircount + buffer size.
	 * We just make sure we make dircount big enough
	 */
	*p++ = cpu_to_be32(args->count >> 3);

	*p = cpu_to_be32(args->count);
}

static void nfs3_xdr_enc_readdirplus3args(struct rpc_rqst *req,
					  struct xdr_stream *xdr,
					  const struct nfs3_readdirargs *args)
{
	encode_readdirplus3args(xdr, args);
	prepare_reply_buffer(req, args->pages, 0,
				args->count, NFS3_readdirres_sz);
}

/*
 * 3.3.21  COMMIT3args
 *
 *	struct COMMIT3args {
 *		nfs_fh3		file;
 *		offset3		offset;
 *		count3		count;
 *	};
 */
static void encode_commit3args(struct xdr_stream *xdr,
			       const struct nfs_writeargs *args)
{
	__be32 *p;

	encode_nfs_fh3(xdr, args->fh);

	p = xdr_reserve_space(xdr, 8 + 4);
	p = xdr_encode_hyper(p, args->offset);
	*p = cpu_to_be32(args->count);
}

static void nfs3_xdr_enc_commit3args(struct rpc_rqst *req,
				     struct xdr_stream *xdr,
				     const struct nfs_writeargs *args)
{
	encode_commit3args(xdr, args);
}

#ifdef CONFIG_NFS_V3_ACL

static void nfs3_xdr_enc_getacl3args(struct rpc_rqst *req,
				     struct xdr_stream *xdr,
				     const struct nfs3_getaclargs *args)
{
	encode_nfs_fh3(xdr, args->fh);
	encode_uint32(xdr, args->mask);
	if (args->mask & (NFS_ACL | NFS_DFACL))
		prepare_reply_buffer(req, args->pages, 0,
					NFSACL_MAXPAGES << PAGE_SHIFT,
					ACL3_getaclres_sz);
}

static void nfs3_xdr_enc_setacl3args(struct rpc_rqst *req,
				     struct xdr_stream *xdr,
				     const struct nfs3_setaclargs *args)
{
	unsigned int base;
	int error;

	encode_nfs_fh3(xdr, NFS_FH(args->inode));
	encode_uint32(xdr, args->mask);
	if (args->npages != 0)
		xdr_write_pages(xdr, args->pages, 0, args->len);

	base = req->rq_slen;
	error = nfsacl_encode(xdr->buf, base, args->inode,
			    (args->mask & NFS_ACL) ?
			    args->acl_access : NULL, 1, 0);
	BUG_ON(error < 0);
	error = nfsacl_encode(xdr->buf, base + error, args->inode,
			    (args->mask & NFS_DFACL) ?
			    args->acl_default : NULL, 1,
			    NFS_ACL_DEFAULT);
	BUG_ON(error < 0);
}

#endif  /* CONFIG_NFS_V3_ACL */

/*
 * NFSv3 XDR decode functions
 *
 * NFSv3 result types are defined in section 3.3 of RFC 1813:
 * "NFS Version 3 Protocol Specification".
 */

/*
 * 3.3.1  GETATTR3res
 *
 *	struct GETATTR3resok {
 *		fattr3		obj_attributes;
 *	};
 *
 *	union GETATTR3res switch (nfsstat3 status) {
 *	case NFS3_OK:
 *		GETATTR3resok  resok;
 *	default:
 *		void;
 *	};
 */
static int nfs3_xdr_dec_getattr3res(struct rpc_rqst *req,
				    struct xdr_stream *xdr,
				    struct nfs_fattr *result)
{
	enum nfs_stat status;
	int error;

	error = decode_nfsstat3(xdr, &status);
	if (unlikely(error))
		goto out;
	if (status != NFS3_OK)
		goto out_default;
	error = decode_fattr3(xdr, result);
out:
	return error;
out_default:
	return nfs_stat_to_errno(status);
}

/*
 * 3.3.2  SETATTR3res
 *
 *	struct SETATTR3resok {
 *		wcc_data  obj_wcc;
 *	};
 *
 *	struct SETATTR3resfail {
 *		wcc_data  obj_wcc;
 *	};
 *
 *	union SETATTR3res switch (nfsstat3 status) {
 *	case NFS3_OK:
 *		SETATTR3resok   resok;
 *	default:
 *		SETATTR3resfail resfail;
 *	};
 */
static int nfs3_xdr_dec_setattr3res(struct rpc_rqst *req,
				    struct xdr_stream *xdr,
				    struct nfs_fattr *result)
{
	enum nfs_stat status;
	int error;

	error = decode_nfsstat3(xdr, &status);
	if (unlikely(error))
		goto out;
	error = decode_wcc_data(xdr, result);
	if (unlikely(error))
		goto out;
	if (status != NFS3_OK)
		goto out_status;
out:
	return error;
out_status:
	return nfs_stat_to_errno(status);
}

/*
 * 3.3.3  LOOKUP3res
 *
 *	struct LOOKUP3resok {
 *		nfs_fh3		object;
 *		post_op_attr	obj_attributes;
 *		post_op_attr	dir_attributes;
 *	};
 *
 *	struct LOOKUP3resfail {
 *		post_op_attr	dir_attributes;
 *	};
 *
 *	union LOOKUP3res switch (nfsstat3 status) {
 *	case NFS3_OK:
 *		LOOKUP3resok	resok;
 *	default:
 *		LOOKUP3resfail	resfail;
 *	};
 */
static int nfs3_xdr_dec_lookup3res(struct rpc_rqst *req,
				   struct xdr_stream *xdr,
				   struct nfs3_diropres *result)
{
	enum nfs_stat status;
	int error;

	error = decode_nfsstat3(xdr, &status);
	if (unlikely(error))
		goto out;
	if (status != NFS3_OK)
		goto out_default;
	error = decode_nfs_fh3(xdr, result->fh);
	if (unlikely(error))
		goto out;
	error = decode_post_op_attr(xdr, result->fattr);
	if (unlikely(error))
		goto out;
	error = decode_post_op_attr(xdr, result->dir_attr);
out:
	return error;
out_default:
	error = decode_post_op_attr(xdr, result->dir_attr);
	if (unlikely(error))
		goto out;
	return nfs_stat_to_errno(status);
}

/*
 * 3.3.4  ACCESS3res
 *
 *	struct ACCESS3resok {
 *		post_op_attr	obj_attributes;
 *		uint32		access;
 *	};
 *
 *	struct ACCESS3resfail {
 *		post_op_attr	obj_attributes;
 *	};
 *
 *	union ACCESS3res switch (nfsstat3 status) {
 *	case NFS3_OK:
 *		ACCESS3resok	resok;
 *	default:
 *		ACCESS3resfail	resfail;
 *	};
 */
static int nfs3_xdr_dec_access3res(struct rpc_rqst *req,
				   struct xdr_stream *xdr,
				   struct nfs3_accessres *result)
{
	enum nfs_stat status;
	int error;

	error = decode_nfsstat3(xdr, &status);
	if (unlikely(error))
		goto out;
	error = decode_post_op_attr(xdr, result->fattr);
	if (unlikely(error))
		goto out;
	if (status != NFS3_OK)
		goto out_default;
	error = decode_uint32(xdr, &result->access);
out:
	return error;
out_default:
	return nfs_stat_to_errno(status);
}

/*
 * 3.3.5  READLINK3res
 *
 *	struct READLINK3resok {
 *		post_op_attr	symlink_attributes;
 *		nfspath3	data;
 *	};
 *
 *	struct READLINK3resfail {
 *		post_op_attr	symlink_attributes;
 *	};
 *
 *	union READLINK3res switch (nfsstat3 status) {
 *	case NFS3_OK:
 *		READLINK3resok	resok;
 *	default:
 *		READLINK3resfail resfail;
 *	};
 */
static int nfs3_xdr_dec_readlink3res(struct rpc_rqst *req,
				     struct xdr_stream *xdr,
				     struct nfs_fattr *result)
{
	enum nfs_stat status;
	int error;

	error = decode_nfsstat3(xdr, &status);
	if (unlikely(error))
		goto out;
	error = decode_post_op_attr(xdr, result);
	if (unlikely(error))
		goto out;
	if (status != NFS3_OK)
		goto out_default;
	error = decode_nfspath3(xdr);
out:
	return error;
out_default:
	return nfs_stat_to_errno(status);
}

/*
 * 3.3.6  READ3res
 *
 *	struct READ3resok {
 *		post_op_attr	file_attributes;
 *		count3		count;
 *		bool		eof;
 *		opaque		data<>;
 *	};
 *
 *	struct READ3resfail {
 *		post_op_attr	file_attributes;
 *	};
 *
 *	union READ3res switch (nfsstat3 status) {
 *	case NFS3_OK:
 *		READ3resok	resok;
 *	default:
 *		READ3resfail	resfail;
 *	};
 */
static int decode_read3resok(struct xdr_stream *xdr,
			     struct nfs_readres *result)
{
	u32 eof, count, ocount, recvd;
	size_t hdrlen;
	__be32 *p;

	p = xdr_inline_decode(xdr, 4 + 4 + 4);
	if (unlikely(p == NULL))
		goto out_overflow;
	count = be32_to_cpup(p++);
	eof = be32_to_cpup(p++);
	ocount = be32_to_cpup(p++);
	if (unlikely(ocount != count))
		goto out_mismatch;
	hdrlen = (u8 *)xdr->p - (u8 *)xdr->iov->iov_base;
	recvd = xdr->buf->len - hdrlen;
	if (unlikely(count > recvd))
		goto out_cheating;

out:
	xdr_read_pages(xdr, count);
	result->eof = eof;
	result->count = count;
	return count;
out_mismatch:
	dprintk("NFS: READ count doesn't match length of opaque: "
		"count %u != ocount %u\n", count, ocount);
	return -EIO;
out_cheating:
	dprintk("NFS: server cheating in read result: "
		"count %u > recvd %u\n", count, recvd);
	count = recvd;
	eof = 0;
	goto out;
out_overflow:
	print_overflow_msg(__func__, xdr);
	return -EIO;
}

static int nfs3_xdr_dec_read3res(struct rpc_rqst *req, struct xdr_stream *xdr,
				 struct nfs_readres *result)
{
	enum nfs_stat status;
	int error;

	error = decode_nfsstat3(xdr, &status);
	if (unlikely(error))
		goto out;
	error = decode_post_op_attr(xdr, result->fattr);
	if (unlikely(error))
		goto out;
	if (status != NFS3_OK)
		goto out_status;
	error = decode_read3resok(xdr, result);
out:
	return error;
out_status:
	return nfs_stat_to_errno(status);
}

/*
 * 3.3.7  WRITE3res
 *
 *	enum stable_how {
 *		UNSTABLE  = 0,
 *		DATA_SYNC = 1,
 *		FILE_SYNC = 2
 *	};
 *
 *	struct WRITE3resok {
 *		wcc_data	file_wcc;
 *		count3		count;
 *		stable_how	committed;
 *		writeverf3	verf;
 *	};
 *
 *	struct WRITE3resfail {
 *		wcc_data	file_wcc;
 *	};
 *
 *	union WRITE3res switch (nfsstat3 status) {
 *	case NFS3_OK:
 *		WRITE3resok	resok;
 *	default:
 *		WRITE3resfail	resfail;
 *	};
 */
static int decode_write3resok(struct xdr_stream *xdr,
			      struct nfs_writeres *result)
{
	__be32 *p;

	p = xdr_inline_decode(xdr, 4 + 4 + NFS3_WRITEVERFSIZE);
	if (unlikely(p == NULL))
		goto out_overflow;
	result->count = be32_to_cpup(p++);
	result->verf->committed = be32_to_cpup(p++);
	if (unlikely(result->verf->committed > NFS_FILE_SYNC))
		goto out_badvalue;
	memcpy(result->verf->verifier, p, NFS3_WRITEVERFSIZE);
	return result->count;
out_badvalue:
	dprintk("NFS: bad stable_how value: %u\n", result->verf->committed);
	return -EIO;
out_overflow:
	print_overflow_msg(__func__, xdr);
	return -EIO;
}

static int nfs3_xdr_dec_write3res(struct rpc_rqst *req, struct xdr_stream *xdr,
				  struct nfs_writeres *result)
{
	enum nfs_stat status;
	int error;

	error = decode_nfsstat3(xdr, &status);
	if (unlikely(error))
		goto out;
	error = decode_wcc_data(xdr, result->fattr);
	if (unlikely(error))
		goto out;
	if (status != NFS3_OK)
		goto out_status;
	error = decode_write3resok(xdr, result);
out:
	return error;
out_status:
	return nfs_stat_to_errno(status);
}

/*
 * 3.3.8  CREATE3res
 *
 *	struct CREATE3resok {
 *		post_op_fh3	obj;
 *		post_op_attr	obj_attributes;
 *		wcc_data	dir_wcc;
 *	};
 *
 *	struct CREATE3resfail {
 *		wcc_data	dir_wcc;
 *	};
 *
 *	union CREATE3res switch (nfsstat3 status) {
 *	case NFS3_OK:
 *		CREATE3resok	resok;
 *	default:
 *		CREATE3resfail	resfail;
 *	};
 */
static int decode_create3resok(struct xdr_stream *xdr,
			       struct nfs3_diropres *result)
{
	int error;

	error = decode_post_op_fh3(xdr, result->fh);
	if (unlikely(error))
		goto out;
	error = decode_post_op_attr(xdr, result->fattr);
	if (unlikely(error))
		goto out;
	/* The server isn't required to return a file handle.
	 * If it didn't, force the client to perform a LOOKUP
	 * to determine the correct file handle and attribute
	 * values for the new object. */
	if (result->fh->size == 0)
		result->fattr->valid = 0;
	error = decode_wcc_data(xdr, result->dir_attr);
out:
	return error;
}

static int nfs3_xdr_dec_create3res(struct rpc_rqst *req,
				   struct xdr_stream *xdr,
				   struct nfs3_diropres *result)
{
	enum nfs_stat status;
	int error;

	error = decode_nfsstat3(xdr, &status);
	if (unlikely(error))
		goto out;
	if (status != NFS3_OK)
		goto out_default;
	error = decode_create3resok(xdr, result);
out:
	return error;
out_default:
	error = decode_wcc_data(xdr, result->dir_attr);
	if (unlikely(error))
		goto out;
	return nfs_stat_to_errno(status);
}

/*
 * 3.3.12  REMOVE3res
 *
 *	struct REMOVE3resok {
 *		wcc_data    dir_wcc;
 *	};
 *
 *	struct REMOVE3resfail {
 *		wcc_data    dir_wcc;
 *	};
 *
 *	union REMOVE3res switch (nfsstat3 status) {
 *	case NFS3_OK:
 *		REMOVE3resok   resok;
 *	default:
 *		REMOVE3resfail resfail;
 *	};
 */
static int nfs3_xdr_dec_remove3res(struct rpc_rqst *req,
				   struct xdr_stream *xdr,
				   struct nfs_removeres *result)
{
	enum nfs_stat status;
	int error;

	error = decode_nfsstat3(xdr, &status);
	if (unlikely(error))
		goto out;
	error = decode_wcc_data(xdr, result->dir_attr);
	if (unlikely(error))
		goto out;
	if (status != NFS3_OK)
		goto out_status;
out:
	return error;
out_status:
	return nfs_stat_to_errno(status);
}

/*
 * 3.3.14  RENAME3res
 *
 *	struct RENAME3resok {
 *		wcc_data	fromdir_wcc;
 *		wcc_data	todir_wcc;
 *	};
 *
 *	struct RENAME3resfail {
 *		wcc_data	fromdir_wcc;
 *		wcc_data	todir_wcc;
 *	};
 *
 *	union RENAME3res switch (nfsstat3 status) {
 *	case NFS3_OK:
 *		RENAME3resok   resok;
 *	default:
 *		RENAME3resfail resfail;
 *	};
 */
static int nfs3_xdr_dec_rename3res(struct rpc_rqst *req,
				   struct xdr_stream *xdr,
				   struct nfs_renameres *result)
{
	enum nfs_stat status;
	int error;

	error = decode_nfsstat3(xdr, &status);
	if (unlikely(error))
		goto out;
	error = decode_wcc_data(xdr, result->old_fattr);
	if (unlikely(error))
		goto out;
	error = decode_wcc_data(xdr, result->new_fattr);
	if (unlikely(error))
		goto out;
	if (status != NFS3_OK)
		goto out_status;
out:
	return error;
out_status:
	return nfs_stat_to_errno(status);
}

/*
 * 3.3.15  LINK3res
 *
 *	struct LINK3resok {
 *		post_op_attr	file_attributes;
 *		wcc_data	linkdir_wcc;
 *	};
 *
 *	struct LINK3resfail {
 *		post_op_attr	file_attributes;
 *		wcc_data	linkdir_wcc;
 *	};
 *
 *	union LINK3res switch (nfsstat3 status) {
 *	case NFS3_OK:
 *		LINK3resok	resok;
 *	default:
 *		LINK3resfail	resfail;
 *	};
 */
static int nfs3_xdr_dec_link3res(struct rpc_rqst *req, struct xdr_stream *xdr,
				 struct nfs3_linkres *result)
{
	enum nfs_stat status;
	int error;

	error = decode_nfsstat3(xdr, &status);
	if (unlikely(error))
		goto out;
	error = decode_post_op_attr(xdr, result->fattr);
	if (unlikely(error))
		goto out;
	error = decode_wcc_data(xdr, result->dir_attr);
	if (unlikely(error))
		goto out;
	if (status != NFS3_OK)
		goto out_status;
out:
	return error;
out_status:
	return nfs_stat_to_errno(status);
}

/**
 * nfs3_decode_dirent - Decode a single NFSv3 directory entry stored in
 *			the local page cache
 * @xdr: XDR stream where entry resides
 * @entry: buffer to fill in with entry data
 * @plus: boolean indicating whether this should be a readdirplus entry
 *
 * Returns zero if successful, otherwise a negative errno value is
 * returned.
 *
 * This function is not invoked during READDIR reply decoding, but
 * rather whenever an application invokes the getdents(2) system call
 * on a directory already in our cache.
 *
 * 3.3.16  entry3
 *
 *	struct entry3 {
 *		fileid3		fileid;
 *		filename3	name;
 *		cookie3		cookie;
 *		fhandle3	filehandle;
 *		post_op_attr3	attributes;
 *		entry3		*nextentry;
 *	};
 *
 * 3.3.17  entryplus3
 *	struct entryplus3 {
 *		fileid3		fileid;
 *		filename3	name;
 *		cookie3		cookie;
 *		post_op_attr	name_attributes;
 *		post_op_fh3	name_handle;
 *		entryplus3	*nextentry;
 *	};
 */
int nfs3_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry,
		       int plus)
{
	struct nfs_entry old = *entry;
	__be32 *p;
	int error;

	p = xdr_inline_decode(xdr, 4);
	if (unlikely(p == NULL))
		goto out_overflow;
	if (*p == xdr_zero) {
		p = xdr_inline_decode(xdr, 4);
		if (unlikely(p == NULL))
			goto out_overflow;
		if (*p == xdr_zero)
			return -EAGAIN;
		entry->eof = 1;
		return -EBADCOOKIE;
	}

	error = decode_fileid3(xdr, &entry->ino);
	if (unlikely(error))
		return error;

	error = decode_inline_filename3(xdr, &entry->name, &entry->len);
	if (unlikely(error))
		return error;

	entry->prev_cookie = entry->cookie;
	error = decode_cookie3(xdr, &entry->cookie);
	if (unlikely(error))
		return error;

	entry->d_type = DT_UNKNOWN;

	if (plus) {
		entry->fattr->valid = 0;
		error = decode_post_op_attr(xdr, entry->fattr);
		if (unlikely(error))
			return error;
		if (entry->fattr->valid & NFS_ATTR_FATTR_V3)
			entry->d_type = nfs_umode_to_dtype(entry->fattr->mode);

		/* In fact, a post_op_fh3: */
		p = xdr_inline_decode(xdr, 4);
		if (unlikely(p == NULL))
			goto out_overflow;
		if (*p != xdr_zero) {
			error = decode_nfs_fh3(xdr, entry->fh);
			if (unlikely(error)) {
				if (error == -E2BIG)
					goto out_truncated;
				return error;
			}
		} else
			zero_nfs_fh3(entry->fh);
	}

	return 0;

out_overflow:
	print_overflow_msg(__func__, xdr);
	return -EAGAIN;
out_truncated:
	dprintk("NFS: directory entry contains invalid file handle\n");
	*entry = old;
	return -EAGAIN;
}

/*
 * 3.3.16  READDIR3res
 *
 *	struct dirlist3 {
 *		entry3		*entries;
 *		bool		eof;
 *	};
 *
 *	struct READDIR3resok {
 *		post_op_attr	dir_attributes;
 *		cookieverf3	cookieverf;
 *		dirlist3	reply;
 *	};
 *
 *	struct READDIR3resfail {
 *		post_op_attr	dir_attributes;
 *	};
 *
 *	union READDIR3res switch (nfsstat3 status) {
 *	case NFS3_OK:
 *		READDIR3resok	resok;
 *	default:
 *		READDIR3resfail	resfail;
 *	};
 *
 * Read the directory contents into the page cache, but otherwise
 * don't touch them.  The actual decoding is done by nfs3_decode_entry()
 * during subsequent nfs_readdir() calls.
 */
static int decode_dirlist3(struct xdr_stream *xdr)
{
	u32 recvd, pglen;
	size_t hdrlen;

	pglen = xdr->buf->page_len;
	hdrlen = (u8 *)xdr->p - (u8 *)xdr->iov->iov_base;
	recvd = xdr->buf->len - hdrlen;
	if (unlikely(pglen > recvd))
		goto out_cheating;
out:
	xdr_read_pages(xdr, pglen);
	return pglen;
out_cheating:
	dprintk("NFS: server cheating in readdir result: "
		"pglen %u > recvd %u\n", pglen, recvd);
	pglen = recvd;
	goto out;
}

static int decode_readdir3resok(struct xdr_stream *xdr,
				struct nfs3_readdirres *result)
{
	int error;

	error = decode_post_op_attr(xdr, result->dir_attr);
	if (unlikely(error))
		goto out;
	/* XXX: do we need to check if result->verf != NULL ? */
	error = decode_cookieverf3(xdr, result->verf);
	if (unlikely(error))
		goto out;
	error = decode_dirlist3(xdr);
out:
	return error;
}

static int nfs3_xdr_dec_readdir3res(struct rpc_rqst *req,
				    struct xdr_stream *xdr,
				    struct nfs3_readdirres *result)
{
	enum nfs_stat status;
	int error;

	error = decode_nfsstat3(xdr, &status);
	if (unlikely(error))
		goto out;
	if (status != NFS3_OK)
		goto out_default;
	error = decode_readdir3resok(xdr, result);
out:
	return error;
out_default:
	error = decode_post_op_attr(xdr, result->dir_attr);
	if (unlikely(error))
		goto out;
	return nfs_stat_to_errno(status);
}

/*
 * 3.3.18  FSSTAT3res
 *
 *	struct FSSTAT3resok {
 *		post_op_attr	obj_attributes;
 *		size3		tbytes;
 *		size3		fbytes;
 *		size3		abytes;
 *		size3		tfiles;
 *		size3		ffiles;
 *		size3		afiles;
 *		uint32		invarsec;
 *	};
 *
 *	struct FSSTAT3resfail {
 *		post_op_attr	obj_attributes;
 *	};
 *
 *	union FSSTAT3res switch (nfsstat3 status) {
 *	case NFS3_OK:
 *		FSSTAT3resok	resok;
 *	default:
 *		FSSTAT3resfail	resfail;
 *	};
 */
static int decode_fsstat3resok(struct xdr_stream *xdr,
			       struct nfs_fsstat *result)
{
	__be32 *p;

	p = xdr_inline_decode(xdr, 8 * 6 + 4);
	if (unlikely(p == NULL))
		goto out_overflow;
	p = xdr_decode_size3(p, &result->tbytes);
	p = xdr_decode_size3(p, &result->fbytes);
	p = xdr_decode_size3(p, &result->abytes);
	p = xdr_decode_size3(p, &result->tfiles);
	p = xdr_decode_size3(p, &result->ffiles);
	xdr_decode_size3(p, &result->afiles);
	/* ignore invarsec */
	return 0;
out_overflow:
	print_overflow_msg(__func__, xdr);
	return -EIO;
}

static int nfs3_xdr_dec_fsstat3res(struct rpc_rqst *req,
				   struct xdr_stream *xdr,
				   struct nfs_fsstat *result)
{
	enum nfs_stat status;
	int error;

	error = decode_nfsstat3(xdr, &status);
	if (unlikely(error))
		goto out;
	error = decode_post_op_attr(xdr, result->fattr);
	if (unlikely(error))
		goto out;
	if (status != NFS3_OK)
		goto out_status;
	error = decode_fsstat3resok(xdr, result);
out:
	return error;
out_status:
	return nfs_stat_to_errno(status);
}

/*
 * 3.3.19  FSINFO3res
 *
 *	struct FSINFO3resok {
 *		post_op_attr	obj_attributes;
 *		uint32		rtmax;
 *		uint32		rtpref;
 *		uint32		rtmult;
 *		uint32		wtmax;
 *		uint32		wtpref;
 *		uint32		wtmult;
 *		uint32		dtpref;
 *		size3		maxfilesize;
 *		nfstime3	time_delta;
 *		uint32		properties;
 *	};
 *
 *	struct FSINFO3resfail {
 *		post_op_attr	obj_attributes;
 *	};
 *
 *	union FSINFO3res switch (nfsstat3 status) {
 *	case NFS3_OK:
 *		FSINFO3resok	resok;
 *	default:
 *		FSINFO3resfail	resfail;
 *	};
 */
static int decode_fsinfo3resok(struct xdr_stream *xdr,
			       struct nfs_fsinfo *result)
{
	__be32 *p;

	p = xdr_inline_decode(xdr, 4 * 7 + 8 + 8 + 4);
	if (unlikely(p == NULL))
		goto out_overflow;
	result->rtmax  = be32_to_cpup(p++);
	result->rtpref = be32_to_cpup(p++);
	result->rtmult = be32_to_cpup(p++);
	result->wtmax  = be32_to_cpup(p++);
	result->wtpref = be32_to_cpup(p++);
	result->wtmult = be32_to_cpup(p++);
	result->dtpref = be32_to_cpup(p++);
	p = xdr_decode_size3(p, &result->maxfilesize);
	xdr_decode_nfstime3(p, &result->time_delta);

	/* ignore properties */
	result->lease_time = 0;
	return 0;
out_overflow:
	print_overflow_msg(__func__, xdr);
	return -EIO;
}

static int nfs3_xdr_dec_fsinfo3res(struct rpc_rqst *req,
				   struct xdr_stream *xdr,
				   struct nfs_fsinfo *result)
{
	enum nfs_stat status;
	int error;

	error = decode_nfsstat3(xdr, &status);
	if (unlikely(error))
		goto out;
	error = decode_post_op_attr(xdr, result->fattr);
	if (unlikely(error))
		goto out;
	if (status != NFS3_OK)
		goto out_status;
	error = decode_fsinfo3resok(xdr, result);
out:
	return error;
out_status:
	return nfs_stat_to_errno(status);
}

/*
 * 3.3.20  PATHCONF3res
 *
 *	struct PATHCONF3resok {
 *		post_op_attr	obj_attributes;
 *		uint32		linkmax;
 *		uint32		name_max;
 *		bool		no_trunc;
 *		bool		chown_restricted;
 *		bool		case_insensitive;
 *		bool		case_preserving;
 *	};
 *
 *	struct PATHCONF3resfail {
 *		post_op_attr	obj_attributes;
 *	};
 *
 *	union PATHCONF3res switch (nfsstat3 status) {
 *	case NFS3_OK:
 *		PATHCONF3resok	resok;
 *	default:
 *		PATHCONF3resfail resfail;
 *	};
 */
static int decode_pathconf3resok(struct xdr_stream *xdr,
				 struct nfs_pathconf *result)
{
	__be32 *p;

	p = xdr_inline_decode(xdr, 4 * 6);
	if (unlikely(p == NULL))
		goto out_overflow;
	result->max_link = be32_to_cpup(p++);
	result->max_namelen = be32_to_cpup(p);
	/* ignore remaining fields */
	return 0;
out_overflow:
	print_overflow_msg(__func__, xdr);
	return -EIO;
}

static int nfs3_xdr_dec_pathconf3res(struct rpc_rqst *req,
				     struct xdr_stream *xdr,
				     struct nfs_pathconf *result)
{
	enum nfs_stat status;
	int error;

	error = decode_nfsstat3(xdr, &status);
	if (unlikely(error))
		goto out;
	error = decode_post_op_attr(xdr, result->fattr);
	if (unlikely(error))
		goto out;
	if (status != NFS3_OK)
		goto out_status;
	error = decode_pathconf3resok(xdr, result);
out:
	return error;
out_status:
	return nfs_stat_to_errno(status);
}

/*
 * 3.3.21  COMMIT3res
 *
 *	struct COMMIT3resok {
 *		wcc_data	file_wcc;
 *		writeverf3	verf;
 *	};
 *
 *	struct COMMIT3resfail {
 *		wcc_data	file_wcc;
 *	};
 *
 *	union COMMIT3res switch (nfsstat3 status) {
 *	case NFS3_OK:
 *		COMMIT3resok	resok;
 *	default:
 *		COMMIT3resfail	resfail;
 *	};
 */
static int nfs3_xdr_dec_commit3res(struct rpc_rqst *req,
				   struct xdr_stream *xdr,
				   struct nfs_writeres *result)
{
	enum nfs_stat status;
	int error;

	error = decode_nfsstat3(xdr, &status);
	if (unlikely(error))
		goto out;
	error = decode_wcc_data(xdr, result->fattr);
	if (unlikely(error))
		goto out;
	if (status != NFS3_OK)
		goto out_status;
	error = decode_writeverf3(xdr, result->verf->verifier);
out:
	return error;
out_status:
	return nfs_stat_to_errno(status);
}

#ifdef CONFIG_NFS_V3_ACL

static inline int decode_getacl3resok(struct xdr_stream *xdr,
				      struct nfs3_getaclres *result)
{
	struct posix_acl **acl;
	unsigned int *aclcnt;
	size_t hdrlen;
	int error;

	error = decode_post_op_attr(xdr, result->fattr);
	if (unlikely(error))
		goto out;
	error = decode_uint32(xdr, &result->mask);
	if (unlikely(error))
		goto out;
	error = -EINVAL;
	if (result->mask & ~(NFS_ACL|NFS_ACLCNT|NFS_DFACL|NFS_DFACLCNT))
		goto out;

	hdrlen = (u8 *)xdr->p - (u8 *)xdr->iov->iov_base;

	acl = NULL;
	if (result->mask & NFS_ACL)
		acl = &result->acl_access;
	aclcnt = NULL;
	if (result->mask & NFS_ACLCNT)
		aclcnt = &result->acl_access_count;
	error = nfsacl_decode(xdr->buf, hdrlen, aclcnt, acl);
	if (unlikely(error <= 0))
		goto out;

	acl = NULL;
	if (result->mask & NFS_DFACL)
		acl = &result->acl_default;
	aclcnt = NULL;
	if (result->mask & NFS_DFACLCNT)
		aclcnt = &result->acl_default_count;
	error = nfsacl_decode(xdr->buf, hdrlen + error, aclcnt, acl);
	if (unlikely(error <= 0))
		return error;
	error = 0;
out:
	return error;
}

static int nfs3_xdr_dec_getacl3res(struct rpc_rqst *req,
				   struct xdr_stream *xdr,
				   struct nfs3_getaclres *result)
{
	enum nfs_stat status;
	int error;

	error = decode_nfsstat3(xdr, &status);
	if (unlikely(error))
		goto out;
	if (status != NFS3_OK)
		goto out_default;
	error = decode_getacl3resok(xdr, result);
out:
	return error;
out_default:
	return nfs_stat_to_errno(status);
}

static int nfs3_xdr_dec_setacl3res(struct rpc_rqst *req,
				   struct xdr_stream *xdr,
				   struct nfs_fattr *result)
{
	enum nfs_stat status;
	int error;

	error = decode_nfsstat3(xdr, &status);
	if (unlikely(error))
		goto out;
	if (status != NFS3_OK)
		goto out_default;
	error = decode_post_op_attr(xdr, result);
out:
	return error;
out_default:
	return nfs_stat_to_errno(status);
}

#endif  /* CONFIG_NFS_V3_ACL */

#define PROC(proc, argtype, restype, timer)				\
[NFS3PROC_##proc] = {							\
	.p_proc      = NFS3PROC_##proc,					\
	.p_encode    = (kxdreproc_t)nfs3_xdr_enc_##argtype##3args,	\
	.p_decode    = (kxdrdproc_t)nfs3_xdr_dec_##restype##3res,	\
	.p_arglen    = NFS3_##argtype##args_sz,				\
	.p_replen    = NFS3_##restype##res_sz,				\
	.p_timer     = timer,						\
	.p_statidx   = NFS3PROC_##proc,					\
	.p_name      = #proc,						\
	}

struct rpc_procinfo	nfs3_procedures[] = {
	PROC(GETATTR,		getattr,	getattr,	1),
	PROC(SETATTR,		setattr,	setattr,	0),
	PROC(LOOKUP,		lookup,		lookup,		2),
	PROC(ACCESS,		access,		access,		1),
	PROC(READLINK,		readlink,	readlink,	3),
	PROC(READ,		read,		read,		3),
	PROC(WRITE,		write,		write,		4),
	PROC(CREATE,		create,		create,		0),
	PROC(MKDIR,		mkdir,		create,		0),
	PROC(SYMLINK,		symlink,	create,		0),
	PROC(MKNOD,		mknod,		create,		0),
	PROC(REMOVE,		remove,		remove,		0),
	PROC(RMDIR,		lookup,		setattr,	0),
	PROC(RENAME,		rename,		rename,		0),
	PROC(LINK,		link,		link,		0),
	PROC(READDIR,		readdir,	readdir,	3),
	PROC(READDIRPLUS,	readdirplus,	readdir,	3),
	PROC(FSSTAT,		getattr,	fsstat,		0),
	PROC(FSINFO,		getattr,	fsinfo,		0),
	PROC(PATHCONF,		getattr,	pathconf,	0),
	PROC(COMMIT,		commit,		commit,		5),
};

struct rpc_version		nfs_version3 = {
	.number			= 3,
	.nrprocs		= ARRAY_SIZE(nfs3_procedures),
	.procs			= nfs3_procedures
};

#ifdef CONFIG_NFS_V3_ACL
static struct rpc_procinfo	nfs3_acl_procedures[] = {
	[ACLPROC3_GETACL] = {
		.p_proc = ACLPROC3_GETACL,
		.p_encode = (kxdreproc_t)nfs3_xdr_enc_getacl3args,
		.p_decode = (kxdrdproc_t)nfs3_xdr_dec_getacl3res,
		.p_arglen = ACL3_getaclargs_sz,
		.p_replen = ACL3_getaclres_sz,
		.p_timer = 1,
		.p_name = "GETACL",
	},
	[ACLPROC3_SETACL] = {
		.p_proc = ACLPROC3_SETACL,
		.p_encode = (kxdreproc_t)nfs3_xdr_enc_setacl3args,
		.p_decode = (kxdrdproc_t)nfs3_xdr_dec_setacl3res,
		.p_arglen = ACL3_setaclargs_sz,
		.p_replen = ACL3_setaclres_sz,
		.p_timer = 0,
		.p_name = "SETACL",
	},
};

struct rpc_version		nfsacl_version3 = {
	.number			= 3,
	.nrprocs		= sizeof(nfs3_acl_procedures)/
				  sizeof(nfs3_acl_procedures[0]),
	.procs			= nfs3_acl_procedures,
};
#endif  /* CONFIG_NFS_V3_ACL */
OpenPOWER on IntegriCloud