aboutsummaryrefslogblamecommitdiffstats
path: root/fs/ext3/namei.c
blob: af193a304ee5868c6bd54db9f8018159940463bb (plain) (tree)
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
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





































                                                                     

                  































































































































































































































































































































































































































































































































































































































































































































































































































































































































                                                                                                     









                                                                                



















































































































































































































































































































































































































































































































































                                                                                                  
                                                              









































































































































































                                                                                            
                                                                            
                                                                           
                                                                             






























                                                                           
                                                                            
                                                                           
                                                                             
































                                                                           
                                                                            
                                                                           
                                                                             































































































































































































































































































                                                                                       
                                                                              

























































                                                                        
                                                                              





















































                                                                    
                                                                            
                                                                           
                                                                             


















































                                                                               
                                                                            








































                                                                               

                                                                               






































































































































































                                                                               
/*
 *  linux/fs/ext3/namei.c
 *
 * Copyright (C) 1992, 1993, 1994, 1995
 * Remy Card (card@masi.ibp.fr)
 * Laboratoire MASI - Institut Blaise Pascal
 * Universite Pierre et Marie Curie (Paris VI)
 *
 *  from
 *
 *  linux/fs/minix/namei.c
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 *
 *  Big-endian to little-endian byte-swapping/bitmaps by
 *        David S. Miller (davem@caip.rutgers.edu), 1995
 *  Directory entry file type support and forward compatibility hooks
 *  	for B-tree directories by Theodore Ts'o (tytso@mit.edu), 1998
 *  Hash Tree Directory indexing (c)
 *  	Daniel Phillips, 2001
 *  Hash Tree Directory indexing porting
 *  	Christopher Li, 2002
 *  Hash Tree Directory indexing cleanup
 * 	Theodore Ts'o, 2002
 */

#include <linux/fs.h>
#include <linux/pagemap.h>
#include <linux/jbd.h>
#include <linux/time.h>
#include <linux/ext3_fs.h>
#include <linux/ext3_jbd.h>
#include <linux/fcntl.h>
#include <linux/stat.h>
#include <linux/string.h>
#include <linux/quotaops.h>
#include <linux/buffer_head.h>
#include <linux/smp_lock.h>

#include "namei.h"
#include "xattr.h"
#include "acl.h"

/*
 * define how far ahead to read directories while searching them.
 */
#define NAMEI_RA_CHUNKS  2
#define NAMEI_RA_BLOCKS  4
#define NAMEI_RA_SIZE        (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS)
#define NAMEI_RA_INDEX(c,b)  (((c) * NAMEI_RA_BLOCKS) + (b))

static struct buffer_head *ext3_append(handle_t *handle,
					struct inode *inode,
					u32 *block, int *err)
{
	struct buffer_head *bh;

	*block = inode->i_size >> inode->i_sb->s_blocksize_bits;

	if ((bh = ext3_bread(handle, inode, *block, 1, err))) {
		inode->i_size += inode->i_sb->s_blocksize;
		EXT3_I(inode)->i_disksize = inode->i_size;
		ext3_journal_get_write_access(handle,bh);
	}
	return bh;
}

#ifndef assert
#define assert(test) J_ASSERT(test)
#endif

#ifndef swap
#define swap(x, y) do { typeof(x) z = x; x = y; y = z; } while (0)
#endif

#ifdef DX_DEBUG
#define dxtrace(command) command
#else
#define dxtrace(command) 
#endif

struct fake_dirent
{
	__le32 inode;
	__le16 rec_len;
	u8 name_len;
	u8 file_type;
};

struct dx_countlimit
{
	__le16 limit;
	__le16 count;
};

struct dx_entry
{
	__le32 hash;
	__le32 block;
};

/*
 * dx_root_info is laid out so that if it should somehow get overlaid by a
 * dirent the two low bits of the hash version will be zero.  Therefore, the
 * hash version mod 4 should never be 0.  Sincerely, the paranoia department.
 */

struct dx_root
{
	struct fake_dirent dot;
	char dot_name[4];
	struct fake_dirent dotdot;
	char dotdot_name[4];
	struct dx_root_info
	{
		__le32 reserved_zero;
		u8 hash_version;
		u8 info_length; /* 8 */
		u8 indirect_levels;
		u8 unused_flags;
	}
	info;
	struct dx_entry	entries[0];
};

struct dx_node
{
	struct fake_dirent fake;
	struct dx_entry	entries[0];
};


struct dx_frame
{
	struct buffer_head *bh;
	struct dx_entry *entries;
	struct dx_entry *at;
};

struct dx_map_entry
{
	u32 hash;
	u32 offs;
};

#ifdef CONFIG_EXT3_INDEX
static inline unsigned dx_get_block (struct dx_entry *entry);
static void dx_set_block (struct dx_entry *entry, unsigned value);
static inline unsigned dx_get_hash (struct dx_entry *entry);
static void dx_set_hash (struct dx_entry *entry, unsigned value);
static unsigned dx_get_count (struct dx_entry *entries);
static unsigned dx_get_limit (struct dx_entry *entries);
static void dx_set_count (struct dx_entry *entries, unsigned value);
static void dx_set_limit (struct dx_entry *entries, unsigned value);
static unsigned dx_root_limit (struct inode *dir, unsigned infosize);
static unsigned dx_node_limit (struct inode *dir);
static struct dx_frame *dx_probe(struct dentry *dentry,
				 struct inode *dir,
				 struct dx_hash_info *hinfo,
				 struct dx_frame *frame,
				 int *err);
static void dx_release (struct dx_frame *frames);
static int dx_make_map (struct ext3_dir_entry_2 *de, int size,
			struct dx_hash_info *hinfo, struct dx_map_entry map[]);
static void dx_sort_map(struct dx_map_entry *map, unsigned count);
static struct ext3_dir_entry_2 *dx_move_dirents (char *from, char *to,
		struct dx_map_entry *offsets, int count);
static struct ext3_dir_entry_2* dx_pack_dirents (char *base, int size);
static void dx_insert_block (struct dx_frame *frame, u32 hash, u32 block);
static int ext3_htree_next_block(struct inode *dir, __u32 hash,
				 struct dx_frame *frame,
				 struct dx_frame *frames, 
				 __u32 *start_hash);
static struct buffer_head * ext3_dx_find_entry(struct dentry *dentry,
		       struct ext3_dir_entry_2 **res_dir, int *err);
static int ext3_dx_add_entry(handle_t *handle, struct dentry *dentry,
			     struct inode *inode);

/*
 * Future: use high four bits of block for coalesce-on-delete flags
 * Mask them off for now.
 */

static inline unsigned dx_get_block (struct dx_entry *entry)
{
	return le32_to_cpu(entry->block) & 0x00ffffff;
}

static inline void dx_set_block (struct dx_entry *entry, unsigned value)
{
	entry->block = cpu_to_le32(value);
}

static inline unsigned dx_get_hash (struct dx_entry *entry)
{
	return le32_to_cpu(entry->hash);
}

static inline void dx_set_hash (struct dx_entry *entry, unsigned value)
{
	entry->hash = cpu_to_le32(value);
}

static inline unsigned dx_get_count (struct dx_entry *entries)
{
	return le16_to_cpu(((struct dx_countlimit *) entries)->count);
}

static inline unsigned dx_get_limit (struct dx_entry *entries)
{
	return le16_to_cpu(((struct dx_countlimit *) entries)->limit);
}

static inline void dx_set_count (struct dx_entry *entries, unsigned value)
{
	((struct dx_countlimit *) entries)->count = cpu_to_le16(value);
}

static inline void dx_set_limit (struct dx_entry *entries, unsigned value)
{
	((struct dx_countlimit *) entries)->limit = cpu_to_le16(value);
}

static inline unsigned dx_root_limit (struct inode *dir, unsigned infosize)
{
	unsigned entry_space = dir->i_sb->s_blocksize - EXT3_DIR_REC_LEN(1) -
		EXT3_DIR_REC_LEN(2) - infosize;
	return 0? 20: entry_space / sizeof(struct dx_entry);
}

static inline unsigned dx_node_limit (struct inode *dir)
{
	unsigned entry_space = dir->i_sb->s_blocksize - EXT3_DIR_REC_LEN(0);
	return 0? 22: entry_space / sizeof(struct dx_entry);
}

/*
 * Debug
 */
#ifdef DX_DEBUG
static void dx_show_index (char * label, struct dx_entry *entries)
{
        int i, n = dx_get_count (entries);
        printk("%s index ", label);
        for (i = 0; i < n; i++)
        {
                printk("%x->%u ", i? dx_get_hash(entries + i): 0, dx_get_block(entries + i));
        }
        printk("\n");
}

struct stats
{ 
	unsigned names;
	unsigned space;
	unsigned bcount;
};

static struct stats dx_show_leaf(struct dx_hash_info *hinfo, struct ext3_dir_entry_2 *de,
				 int size, int show_names)
{
	unsigned names = 0, space = 0;
	char *base = (char *) de;
	struct dx_hash_info h = *hinfo;

	printk("names: ");
	while ((char *) de < base + size)
	{
		if (de->inode)
		{
			if (show_names)
			{
				int len = de->name_len;
				char *name = de->name;
				while (len--) printk("%c", *name++);
				ext3fs_dirhash(de->name, de->name_len, &h);
				printk(":%x.%u ", h.hash,
				       ((char *) de - base));
			}
			space += EXT3_DIR_REC_LEN(de->name_len);
	 		names++;
		}
		de = (struct ext3_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len));
	}
	printk("(%i)\n", names);
	return (struct stats) { names, space, 1 };
}

struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir,
			     struct dx_entry *entries, int levels)
{
	unsigned blocksize = dir->i_sb->s_blocksize;
	unsigned count = dx_get_count (entries), names = 0, space = 0, i;
	unsigned bcount = 0;
	struct buffer_head *bh;
	int err;
	printk("%i indexed blocks...\n", count);
	for (i = 0; i < count; i++, entries++)
	{
		u32 block = dx_get_block(entries), hash = i? dx_get_hash(entries): 0;
		u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash;
		struct stats stats;
		printk("%s%3u:%03u hash %8x/%8x ",levels?"":"   ", i, block, hash, range);
		if (!(bh = ext3_bread (NULL,dir, block, 0,&err))) continue;
		stats = levels?
		   dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1):
		   dx_show_leaf(hinfo, (struct ext3_dir_entry_2 *) bh->b_data, blocksize, 0);
		names += stats.names;
		space += stats.space;
		bcount += stats.bcount;
		brelse (bh);
	}
	if (bcount)
		printk("%snames %u, fullness %u (%u%%)\n", levels?"":"   ",
			names, space/bcount,(space/bcount)*100/blocksize);
	return (struct stats) { names, space, bcount};
}
#endif /* DX_DEBUG */

/*
 * Probe for a directory leaf block to search.
 *
 * dx_probe can return ERR_BAD_DX_DIR, which means there was a format
 * error in the directory index, and the caller should fall back to
 * searching the directory normally.  The callers of dx_probe **MUST**
 * check for this error code, and make sure it never gets reflected
 * back to userspace.
 */
static struct dx_frame *
dx_probe(struct dentry *dentry, struct inode *dir,
	 struct dx_hash_info *hinfo, struct dx_frame *frame_in, int *err)
{
	unsigned count, indirect;
	struct dx_entry *at, *entries, *p, *q, *m;
	struct dx_root *root;
	struct buffer_head *bh;
	struct dx_frame *frame = frame_in;
	u32 hash;

	frame->bh = NULL;
	if (dentry)
		dir = dentry->d_parent->d_inode;
	if (!(bh = ext3_bread (NULL,dir, 0, 0, err)))
		goto fail;
	root = (struct dx_root *) bh->b_data;
	if (root->info.hash_version != DX_HASH_TEA &&
	    root->info.hash_version != DX_HASH_HALF_MD4 &&
	    root->info.hash_version != DX_HASH_LEGACY) {
		ext3_warning(dir->i_sb, __FUNCTION__,
			     "Unrecognised inode hash code %d",
			     root->info.hash_version);
		brelse(bh);
		*err = ERR_BAD_DX_DIR;
		goto fail;
	}
	hinfo->hash_version = root->info.hash_version;
	hinfo->seed = EXT3_SB(dir->i_sb)->s_hash_seed;
	if (dentry)
		ext3fs_dirhash(dentry->d_name.name, dentry->d_name.len, hinfo);
	hash = hinfo->hash;

	if (root->info.unused_flags & 1) {
		ext3_warning(dir->i_sb, __FUNCTION__,
			     "Unimplemented inode hash flags: %#06x",
			     root->info.unused_flags);
		brelse(bh);
		*err = ERR_BAD_DX_DIR;
		goto fail;
	}

	if ((indirect = root->info.indirect_levels) > 1) {
		ext3_warning(dir->i_sb, __FUNCTION__,
			     "Unimplemented inode hash depth: %#06x",
			     root->info.indirect_levels);
		brelse(bh);
		*err = ERR_BAD_DX_DIR;
		goto fail;
	}

	entries = (struct dx_entry *) (((char *)&root->info) +
				       root->info.info_length);
	assert(dx_get_limit(entries) == dx_root_limit(dir,
						      root->info.info_length));
	dxtrace (printk("Look up %x", hash));
	while (1)
	{
		count = dx_get_count(entries);
		assert (count && count <= dx_get_limit(entries));
		p = entries + 1;
		q = entries + count - 1;
		while (p <= q)
		{
			m = p + (q - p)/2;
			dxtrace(printk("."));
			if (dx_get_hash(m) > hash)
				q = m - 1;
			else
				p = m + 1;
		}

		if (0) // linear search cross check
		{
			unsigned n = count - 1;
			at = entries;
			while (n--)
			{
				dxtrace(printk(","));
				if (dx_get_hash(++at) > hash)
				{
					at--;
					break;
				}
			}
			assert (at == p - 1);
		}

		at = p - 1;
		dxtrace(printk(" %x->%u\n", at == entries? 0: dx_get_hash(at), dx_get_block(at)));
		frame->bh = bh;
		frame->entries = entries;
		frame->at = at;
		if (!indirect--) return frame;
		if (!(bh = ext3_bread (NULL,dir, dx_get_block(at), 0, err)))
			goto fail2;
		at = entries = ((struct dx_node *) bh->b_data)->entries;
		assert (dx_get_limit(entries) == dx_node_limit (dir));
		frame++;
	}
fail2:
	while (frame >= frame_in) {
		brelse(frame->bh);
		frame--;
	}
fail:
	return NULL;
}

static void dx_release (struct dx_frame *frames)
{
	if (frames[0].bh == NULL)
		return;

	if (((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels)
		brelse(frames[1].bh);
	brelse(frames[0].bh);
}

/*
 * This function increments the frame pointer to search the next leaf
 * block, and reads in the necessary intervening nodes if the search
 * should be necessary.  Whether or not the search is necessary is
 * controlled by the hash parameter.  If the hash value is even, then
 * the search is only continued if the next block starts with that
 * hash value.  This is used if we are searching for a specific file.
 *
 * If the hash value is HASH_NB_ALWAYS, then always go to the next block.
 *
 * This function returns 1 if the caller should continue to search,
 * or 0 if it should not.  If there is an error reading one of the
 * index blocks, it will a negative error code.
 *
 * If start_hash is non-null, it will be filled in with the starting
 * hash of the next page.
 */
static int ext3_htree_next_block(struct inode *dir, __u32 hash,
				 struct dx_frame *frame,
				 struct dx_frame *frames, 
				 __u32 *start_hash)
{
	struct dx_frame *p;
	struct buffer_head *bh;
	int err, num_frames = 0;
	__u32 bhash;

	p = frame;
	/*
	 * Find the next leaf page by incrementing the frame pointer.
	 * If we run out of entries in the interior node, loop around and
	 * increment pointer in the parent node.  When we break out of
	 * this loop, num_frames indicates the number of interior
	 * nodes need to be read.
	 */
	while (1) {
		if (++(p->at) < p->entries + dx_get_count(p->entries))
			break;
		if (p == frames)
			return 0;
		num_frames++;
		p--;
	}

	/*
	 * If the hash is 1, then continue only if the next page has a
	 * continuation hash of any value.  This is used for readdir
	 * handling.  Otherwise, check to see if the hash matches the
	 * desired contiuation hash.  If it doesn't, return since
	 * there's no point to read in the successive index pages.
	 */
	bhash = dx_get_hash(p->at);
	if (start_hash)
		*start_hash = bhash;
	if ((hash & 1) == 0) {
		if ((bhash & ~1) != hash)
			return 0;
	}
	/*
	 * If the hash is HASH_NB_ALWAYS, we always go to the next
	 * block so no check is necessary
	 */
	while (num_frames--) {
		if (!(bh = ext3_bread(NULL, dir, dx_get_block(p->at),
				      0, &err)))
			return err; /* Failure */
		p++;
		brelse (p->bh);
		p->bh = bh;
		p->at = p->entries = ((struct dx_node *) bh->b_data)->entries;
	}
	return 1;
}


/*
 * p is at least 6 bytes before the end of page
 */
static inline struct ext3_dir_entry_2 *ext3_next_entry(struct ext3_dir_entry_2 *p)
{
	return (struct ext3_dir_entry_2 *)((char*)p + le16_to_cpu(p->rec_len));
}

/*
 * This function fills a red-black tree with information from a
 * directory block.  It returns the number directory entries loaded
 * into the tree.  If there is an error it is returned in err.
 */
static int htree_dirblock_to_tree(struct file *dir_file,
				  struct inode *dir, int block,
				  struct dx_hash_info *hinfo,
				  __u32 start_hash, __u32 start_minor_hash)
{
	struct buffer_head *bh;
	struct ext3_dir_entry_2 *de, *top;
	int err, count = 0;

	dxtrace(printk("In htree dirblock_to_tree: block %d\n", block));
	if (!(bh = ext3_bread (NULL, dir, block, 0, &err)))
		return err;

	de = (struct ext3_dir_entry_2 *) bh->b_data;
	top = (struct ext3_dir_entry_2 *) ((char *) de +
					   dir->i_sb->s_blocksize -
					   EXT3_DIR_REC_LEN(0));
	for (; de < top; de = ext3_next_entry(de)) {
		ext3fs_dirhash(de->name, de->name_len, hinfo);
		if ((hinfo->hash < start_hash) ||
		    ((hinfo->hash == start_hash) &&
		     (hinfo->minor_hash < start_minor_hash)))
			continue;
		if (de->inode == 0)
			continue;
		if ((err = ext3_htree_store_dirent(dir_file,
				   hinfo->hash, hinfo->minor_hash, de)) != 0) {
			brelse(bh);
			return err;
		}
		count++;
	}
	brelse(bh);
	return count;
}


/*
 * This function fills a red-black tree with information from a
 * directory.  We start scanning the directory in hash order, starting
 * at start_hash and start_minor_hash.
 *
 * This function returns the number of entries inserted into the tree,
 * or a negative error code.
 */
int ext3_htree_fill_tree(struct file *dir_file, __u32 start_hash,
			 __u32 start_minor_hash, __u32 *next_hash)
{
	struct dx_hash_info hinfo;
	struct ext3_dir_entry_2 *de;
	struct dx_frame frames[2], *frame;
	struct inode *dir;
	int block, err;
	int count = 0;
	int ret;
	__u32 hashval;

	dxtrace(printk("In htree_fill_tree, start hash: %x:%x\n", start_hash,
		       start_minor_hash));
	dir = dir_file->f_dentry->d_inode;
	if (!(EXT3_I(dir)->i_flags & EXT3_INDEX_FL)) {
		hinfo.hash_version = EXT3_SB(dir->i_sb)->s_def_hash_version;
		hinfo.seed = EXT3_SB(dir->i_sb)->s_hash_seed;
		count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo,
					       start_hash, start_minor_hash);
		*next_hash = ~0;
		return count;
	}
	hinfo.hash = start_hash;
	hinfo.minor_hash = 0;
	frame = dx_probe(NULL, dir_file->f_dentry->d_inode, &hinfo, frames, &err);
	if (!frame)
		return err;

	/* Add '.' and '..' from the htree header */
	if (!start_hash && !start_minor_hash) {
		de = (struct ext3_dir_entry_2 *) frames[0].bh->b_data;
		if ((err = ext3_htree_store_dirent(dir_file, 0, 0, de)) != 0)
			goto errout;
		count++;
	}
	if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) {
		de = (struct ext3_dir_entry_2 *) frames[0].bh->b_data;
		de = ext3_next_entry(de);
		if ((err = ext3_htree_store_dirent(dir_file, 2, 0, de)) != 0)
			goto errout;
		count++;
	}

	while (1) {
		block = dx_get_block(frame->at);
		ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo,
					     start_hash, start_minor_hash);
		if (ret < 0) {
			err = ret;
			goto errout;
		}
		count += ret;
		hashval = ~0;
		ret = ext3_htree_next_block(dir, HASH_NB_ALWAYS, 
					    frame, frames, &hashval);
		*next_hash = hashval;
		if (ret < 0) {
			err = ret;
			goto errout;
		}
		/*
		 * Stop if:  (a) there are no more entries, or
		 * (b) we have inserted at least one entry and the
		 * next hash value is not a continuation
		 */
		if ((ret == 0) ||
		    (count && ((hashval & 1) == 0)))
			break;
	}
	dx_release(frames);
	dxtrace(printk("Fill tree: returned %d entries, next hash: %x\n", 
		       count, *next_hash));
	return count;
errout:
	dx_release(frames);
	return (err);
}


/*
 * Directory block splitting, compacting
 */

static int dx_make_map (struct ext3_dir_entry_2 *de, int size,
			struct dx_hash_info *hinfo, struct dx_map_entry *map_tail)
{
	int count = 0;
	char *base = (char *) de;
	struct dx_hash_info h = *hinfo;

	while ((char *) de < base + size)
	{
		if (de->name_len && de->inode) {
			ext3fs_dirhash(de->name, de->name_len, &h);
			map_tail--;
			map_tail->hash = h.hash;
			map_tail->offs = (u32) ((char *) de - base);
			count++;
			cond_resched();
		}
		/* XXX: do we need to check rec_len == 0 case? -Chris */
		de = (struct ext3_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len));
	}
	return count;
}

static void dx_sort_map (struct dx_map_entry *map, unsigned count)
{
        struct dx_map_entry *p, *q, *top = map + count - 1;
        int more;
        /* Combsort until bubble sort doesn't suck */
        while (count > 2)
	{
                count = count*10/13;
                if (count - 9 < 2) /* 9, 10 -> 11 */
                        count = 11;
                for (p = top, q = p - count; q >= map; p--, q--)
                        if (p->hash < q->hash)
                                swap(*p, *q);
        }
        /* Garden variety bubble sort */
        do {
                more = 0;
                q = top;
                while (q-- > map)
		{
                        if (q[1].hash >= q[0].hash)
				continue;
                        swap(*(q+1), *q);
                        more = 1;
		}
	} while(more);
}

static void dx_insert_block(struct dx_frame *frame, u32 hash, u32 block)
{
	struct dx_entry *entries = frame->entries;
	struct dx_entry *old = frame->at, *new = old + 1;
	int count = dx_get_count(entries);

	assert(count < dx_get_limit(entries));
	assert(old < entries + count);
	memmove(new + 1, new, (char *)(entries + count) - (char *)(new));
	dx_set_hash(new, hash);
	dx_set_block(new, block);
	dx_set_count(entries, count + 1);
}
#endif


static void ext3_update_dx_flag(struct inode *inode)
{
	if (!EXT3_HAS_COMPAT_FEATURE(inode->i_sb,
				     EXT3_FEATURE_COMPAT_DIR_INDEX))
		EXT3_I(inode)->i_flags &= ~EXT3_INDEX_FL;
}

/*
 * NOTE! unlike strncmp, ext3_match returns 1 for success, 0 for failure.
 *
 * `len <= EXT3_NAME_LEN' is guaranteed by caller.
 * `de != NULL' is guaranteed by caller.
 */
static inline int ext3_match (int len, const char * const name,
			      struct ext3_dir_entry_2 * de)
{
	if (len != de->name_len)
		return 0;
	if (!de->inode)
		return 0;
	return !memcmp(name, de->name, len);
}

/*
 * Returns 0 if not found, -1 on failure, and 1 on success
 */
static inline int search_dirblock(struct buffer_head * bh,
				  struct inode *dir,
				  struct dentry *dentry,
				  unsigned long offset,
				  struct ext3_dir_entry_2 ** res_dir)
{
	struct ext3_dir_entry_2 * de;
	char * dlimit;
	int de_len;
	const char *name = dentry->d_name.name;
	int namelen = dentry->d_name.len;

	de = (struct ext3_dir_entry_2 *) bh->b_data;
	dlimit = bh->b_data + dir->i_sb->s_blocksize;
	while ((char *) de < dlimit) {
		/* this code is executed quadratically often */
		/* do minimal checking `by hand' */

		if ((char *) de + namelen <= dlimit &&
		    ext3_match (namelen, name, de)) {
			/* found a match - just to be sure, do a full check */
			if (!ext3_check_dir_entry("ext3_find_entry",
						  dir, de, bh, offset))
				return -1;
			*res_dir = de;
			return 1;
		}
		/* prevent looping on a bad block */
		de_len = le16_to_cpu(de->rec_len);
		if (de_len <= 0)
			return -1;
		offset += de_len;
		de = (struct ext3_dir_entry_2 *) ((char *) de + de_len);
	}
	return 0;
}


/*
 *	ext3_find_entry()
 *
 * finds an entry in the specified directory with the wanted name. It
 * returns the cache buffer in which the entry was found, and the entry
 * itself (as a parameter - res_dir). It does NOT read the inode of the
 * entry - you'll have to do that yourself if you want to.
 *
 * The returned buffer_head has ->b_count elevated.  The caller is expected
 * to brelse() it when appropriate.
 */
static struct buffer_head * ext3_find_entry (struct dentry *dentry,
					struct ext3_dir_entry_2 ** res_dir)
{
	struct super_block * sb;
	struct buffer_head * bh_use[NAMEI_RA_SIZE];
	struct buffer_head * bh, *ret = NULL;
	unsigned long start, block, b;
	int ra_max = 0;		/* Number of bh's in the readahead
				   buffer, bh_use[] */
	int ra_ptr = 0;		/* Current index into readahead
				   buffer */
	int num = 0;
	int nblocks, i, err;
	struct inode *dir = dentry->d_parent->d_inode;
	int namelen;
	const u8 *name;
	unsigned blocksize;

	*res_dir = NULL;
	sb = dir->i_sb;
	blocksize = sb->s_blocksize;
	namelen = dentry->d_name.len;
	name = dentry->d_name.name;
	if (namelen > EXT3_NAME_LEN)
		return NULL;
#ifdef CONFIG_EXT3_INDEX
	if (is_dx(dir)) {
		bh = ext3_dx_find_entry(dentry, res_dir, &err);
		/*
		 * On success, or if the error was file not found,
		 * return.  Otherwise, fall back to doing a search the
		 * old fashioned way.
		 */
		if (bh || (err != ERR_BAD_DX_DIR))
			return bh;
		dxtrace(printk("ext3_find_entry: dx failed, falling back\n"));
	}
#endif
	nblocks = dir->i_size >> EXT3_BLOCK_SIZE_BITS(sb);
	start = EXT3_I(dir)->i_dir_start_lookup;
	if (start >= nblocks)
		start = 0;
	block = start;
restart:
	do {
		/*
		 * We deal with the read-ahead logic here.
		 */
		if (ra_ptr >= ra_max) {
			/* Refill the readahead buffer */
			ra_ptr = 0;
			b = block;
			for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) {
				/*
				 * Terminate if we reach the end of the
				 * directory and must wrap, or if our
				 * search has finished at this block.
				 */
				if (b >= nblocks || (num && block == start)) {
					bh_use[ra_max] = NULL;
					break;
				}
				num++;
				bh = ext3_getblk(NULL, dir, b++, 0, &err);
				bh_use[ra_max] = bh;
				if (bh)
					ll_rw_block(READ, 1, &bh);
			}
		}
		if ((bh = bh_use[ra_ptr++]) == NULL)
			goto next;
		wait_on_buffer(bh);
		if (!buffer_uptodate(bh)) {
			/* read error, skip block & hope for the best */
			ext3_error(sb, __FUNCTION__, "reading directory #%lu "
				   "offset %lu", dir->i_ino, block);
			brelse(bh);
			goto next;
		}
		i = search_dirblock(bh, dir, dentry,
			    block << EXT3_BLOCK_SIZE_BITS(sb), res_dir);
		if (i == 1) {
			EXT3_I(dir)->i_dir_start_lookup = block;
			ret = bh;
			goto cleanup_and_exit;
		} else {
			brelse(bh);
			if (i < 0)
				goto cleanup_and_exit;
		}
	next:
		if (++block >= nblocks)
			block = 0;
	} while (block != start);

	/*
	 * If the directory has grown while we were searching, then
	 * search the last part of the directory before giving up.
	 */
	block = nblocks;
	nblocks = dir->i_size >> EXT3_BLOCK_SIZE_BITS(sb);
	if (block < nblocks) {
		start = 0;
		goto restart;
	}

cleanup_and_exit:
	/* Clean up the read-ahead blocks */
	for (; ra_ptr < ra_max; ra_ptr++)
		brelse (bh_use[ra_ptr]);
	return ret;
}

#ifdef CONFIG_EXT3_INDEX
static struct buffer_head * ext3_dx_find_entry(struct dentry *dentry,
		       struct ext3_dir_entry_2 **res_dir, int *err)
{
	struct super_block * sb;
	struct dx_hash_info	hinfo;
	u32 hash;
	struct dx_frame frames[2], *frame;
	struct ext3_dir_entry_2 *de, *top;
	struct buffer_head *bh;
	unsigned long block;
	int retval;
	int namelen = dentry->d_name.len;
	const u8 *name = dentry->d_name.name;
	struct inode *dir = dentry->d_parent->d_inode;

	sb = dir->i_sb;
	/* NFS may look up ".." - look at dx_root directory block */
	if (namelen > 2 || name[0] != '.'||(name[1] != '.' && name[1] != '\0')){
		if (!(frame = dx_probe(dentry, NULL, &hinfo, frames, err)))
			return NULL;
	} else {
		frame = frames;
		frame->bh = NULL;			/* for dx_release() */
		frame->at = (struct dx_entry *)frames;	/* hack for zero entry*/
		dx_set_block(frame->at, 0);		/* dx_root block is 0 */
	}
	hash = hinfo.hash;
	do {
		block = dx_get_block(frame->at);
		if (!(bh = ext3_bread (NULL,dir, block, 0, err)))
			goto errout;
		de = (struct ext3_dir_entry_2 *) bh->b_data;
		top = (struct ext3_dir_entry_2 *) ((char *) de + sb->s_blocksize -
				       EXT3_DIR_REC_LEN(0));
		for (; de < top; de = ext3_next_entry(de))
		if (ext3_match (namelen, name, de)) {
			if (!ext3_check_dir_entry("ext3_find_entry",
						  dir, de, bh,
				  (block<<EXT3_BLOCK_SIZE_BITS(sb))
					  +((char *)de - bh->b_data))) {
				brelse (bh);
				goto errout;
			}
			*res_dir = de;
			dx_release (frames);
			return bh;
		}
		brelse (bh);
		/* Check to see if we should continue to search */
		retval = ext3_htree_next_block(dir, hash, frame,
					       frames, NULL);
		if (retval < 0) {
			ext3_warning(sb, __FUNCTION__,
			     "error reading index page in directory #%lu",
			     dir->i_ino);
			*err = retval;
			goto errout;
		}
	} while (retval == 1);

	*err = -ENOENT;
errout:
	dxtrace(printk("%s not found\n", name));
	dx_release (frames);
	return NULL;
}
#endif

static struct dentry *ext3_lookup(struct inode * dir, struct dentry *dentry, struct nameidata *nd)
{
	struct inode * inode;
	struct ext3_dir_entry_2 * de;
	struct buffer_head * bh;

	if (dentry->d_name.len > EXT3_NAME_LEN)
		return ERR_PTR(-ENAMETOOLONG);

	bh = ext3_find_entry(dentry, &de);
	inode = NULL;
	if (bh) {
		unsigned long ino = le32_to_cpu(de->inode);
		brelse (bh);
		inode = iget(dir->i_sb, ino);

		if (!inode)
			return ERR_PTR(-EACCES);
	}
	if (inode)
		return d_splice_alias(inode, dentry);
	d_add(dentry, inode);
	return NULL;
}


struct dentry *ext3_get_parent(struct dentry *child)
{
	unsigned long ino;
	struct dentry *parent;
	struct inode *inode;
	struct dentry dotdot;
	struct ext3_dir_entry_2 * de;
	struct buffer_head *bh;

	dotdot.d_name.name = "..";
	dotdot.d_name.len = 2;
	dotdot.d_parent = child; /* confusing, isn't it! */

	bh = ext3_find_entry(&dotdot, &de);
	inode = NULL;
	if (!bh)
		return ERR_PTR(-ENOENT);
	ino = le32_to_cpu(de->inode);
	brelse(bh);
	inode = iget(child->d_inode->i_sb, ino);

	if (!inode)
		return ERR_PTR(-EACCES);

	parent = d_alloc_anon(inode);
	if (!parent) {
		iput(inode);
		parent = ERR_PTR(-ENOMEM);
	}
	return parent;
} 

#define S_SHIFT 12
static unsigned char ext3_type_by_mode[S_IFMT >> S_SHIFT] = {
	[S_IFREG >> S_SHIFT]	= EXT3_FT_REG_FILE,
	[S_IFDIR >> S_SHIFT]	= EXT3_FT_DIR,
	[S_IFCHR >> S_SHIFT]	= EXT3_FT_CHRDEV,
	[S_IFBLK >> S_SHIFT]	= EXT3_FT_BLKDEV,
	[S_IFIFO >> S_SHIFT]	= EXT3_FT_FIFO,
	[S_IFSOCK >> S_SHIFT]	= EXT3_FT_SOCK,
	[S_IFLNK >> S_SHIFT]	= EXT3_FT_SYMLINK,
};

static inline void ext3_set_de_type(struct super_block *sb,
				struct ext3_dir_entry_2 *de,
				umode_t mode) {
	if (EXT3_HAS_INCOMPAT_FEATURE(sb, EXT3_FEATURE_INCOMPAT_FILETYPE))
		de->file_type = ext3_type_by_mode[(mode & S_IFMT)>>S_SHIFT];
}

#ifdef CONFIG_EXT3_INDEX
static struct ext3_dir_entry_2 *
dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count)
{
	unsigned rec_len = 0;

	while (count--) {
		struct ext3_dir_entry_2 *de = (struct ext3_dir_entry_2 *) (from + map->offs);
		rec_len = EXT3_DIR_REC_LEN(de->name_len);
		memcpy (to, de, rec_len);
		((struct ext3_dir_entry_2 *) to)->rec_len =
				cpu_to_le16(rec_len);
		de->inode = 0;
		map++;
		to += rec_len;
	}
	return (struct ext3_dir_entry_2 *) (to - rec_len);
}

static struct ext3_dir_entry_2* dx_pack_dirents(char *base, int size)
{
	struct ext3_dir_entry_2 *next, *to, *prev, *de = (struct ext3_dir_entry_2 *) base;
	unsigned rec_len = 0;

	prev = to = de;
	while ((char*)de < base + size) {
		next = (struct ext3_dir_entry_2 *) ((char *) de +
						    le16_to_cpu(de->rec_len));
		if (de->inode && de->name_len) {
			rec_len = EXT3_DIR_REC_LEN(de->name_len);
			if (de > to)
				memmove(to, de, rec_len);
			to->rec_len = cpu_to_le16(rec_len);
			prev = to;
			to = (struct ext3_dir_entry_2 *) (((char *) to) + rec_len);
		}
		de = next;
	}
	return prev;
}

static struct ext3_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
			struct buffer_head **bh,struct dx_frame *frame,
			struct dx_hash_info *hinfo, int *error)
{
	unsigned blocksize = dir->i_sb->s_blocksize;
	unsigned count, continued;
	struct buffer_head *bh2;
	u32 newblock;
	u32 hash2;
	struct dx_map_entry *map;
	char *data1 = (*bh)->b_data, *data2;
	unsigned split;
	struct ext3_dir_entry_2 *de = NULL, *de2;
	int	err;

	bh2 = ext3_append (handle, dir, &newblock, error);
	if (!(bh2)) {
		brelse(*bh);
		*bh = NULL;
		goto errout;
	}

	BUFFER_TRACE(*bh, "get_write_access");
	err = ext3_journal_get_write_access(handle, *bh);
	if (err) {
	journal_error:
		brelse(*bh);
		brelse(bh2);
		*bh = NULL;
		ext3_std_error(dir->i_sb, err);
		goto errout;
	}
	BUFFER_TRACE(frame->bh, "get_write_access");
	err = ext3_journal_get_write_access(handle, frame->bh);
	if (err)
		goto journal_error;

	data2 = bh2->b_data;

	/* create map in the end of data2 block */
	map = (struct dx_map_entry *) (data2 + blocksize);
	count = dx_make_map ((struct ext3_dir_entry_2 *) data1,
			     blocksize, hinfo, map);
	map -= count;
	split = count/2; // need to adjust to actual middle
	dx_sort_map (map, count);
	hash2 = map[split].hash;
	continued = hash2 == map[split - 1].hash;
	dxtrace(printk("Split block %i at %x, %i/%i\n",
		dx_get_block(frame->at), hash2, split, count-split));

	/* Fancy dance to stay within two buffers */
	de2 = dx_move_dirents(data1, data2, map + split, count - split);
	de = dx_pack_dirents(data1,blocksize);
	de->rec_len = cpu_to_le16(data1 + blocksize - (char *) de);
	de2->rec_len = cpu_to_le16(data2 + blocksize - (char *) de2);
	dxtrace(dx_show_leaf (hinfo, (struct ext3_dir_entry_2 *) data1, blocksize, 1));
	dxtrace(dx_show_leaf (hinfo, (struct ext3_dir_entry_2 *) data2, blocksize, 1));

	/* Which block gets the new entry? */
	if (hinfo->hash >= hash2)
	{
		swap(*bh, bh2);
		de = de2;
	}
	dx_insert_block (frame, hash2 + continued, newblock);
	err = ext3_journal_dirty_metadata (handle, bh2);
	if (err)
		goto journal_error;
	err = ext3_journal_dirty_metadata (handle, frame->bh);
	if (err)
		goto journal_error;
	brelse (bh2);
	dxtrace(dx_show_index ("frame", frame->entries));
errout:
	return de;
}
#endif


/*
 * Add a new entry into a directory (leaf) block.  If de is non-NULL,
 * it points to a directory entry which is guaranteed to be large
 * enough for new directory entry.  If de is NULL, then
 * add_dirent_to_buf will attempt search the directory block for
 * space.  It will return -ENOSPC if no space is available, and -EIO
 * and -EEXIST if directory entry already exists.
 * 
 * NOTE!  bh is NOT released in the case where ENOSPC is returned.  In
 * all other cases bh is released.
 */
static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry,
			     struct inode *inode, struct ext3_dir_entry_2 *de,
			     struct buffer_head * bh)
{
	struct inode	*dir = dentry->d_parent->d_inode;
	const char	*name = dentry->d_name.name;
	int		namelen = dentry->d_name.len;
	unsigned long	offset = 0;
	unsigned short	reclen;
	int		nlen, rlen, err;
	char		*top;

	reclen = EXT3_DIR_REC_LEN(namelen);
	if (!de) {
		de = (struct ext3_dir_entry_2 *)bh->b_data;
		top = bh->b_data + dir->i_sb->s_blocksize - reclen;
		while ((char *) de <= top) {
			if (!ext3_check_dir_entry("ext3_add_entry", dir, de,
						  bh, offset)) {
				brelse (bh);
				return -EIO;
			}
			if (ext3_match (namelen, name, de)) {
				brelse (bh);
				return -EEXIST;
			}
			nlen = EXT3_DIR_REC_LEN(de->name_len);
			rlen = le16_to_cpu(de->rec_len);
			if ((de->inode? rlen - nlen: rlen) >= reclen)
				break;
			de = (struct ext3_dir_entry_2 *)((char *)de + rlen);
			offset += rlen;
		}
		if ((char *) de > top)
			return -ENOSPC;
	}
	BUFFER_TRACE(bh, "get_write_access");
	err = ext3_journal_get_write_access(handle, bh);
	if (err) {
		ext3_std_error(dir->i_sb, err);
		brelse(bh);
		return err;
	}

	/* By now the buffer is marked for journaling */
	nlen = EXT3_DIR_REC_LEN(de->name_len);
	rlen = le16_to_cpu(de->rec_len);
	if (de->inode) {
		struct ext3_dir_entry_2 *de1 = (struct ext3_dir_entry_2 *)((char *)de + nlen);
		de1->rec_len = cpu_to_le16(rlen - nlen);
		de->rec_len = cpu_to_le16(nlen);
		de = de1;
	}
	de->file_type = EXT3_FT_UNKNOWN;
	if (inode) {
		de->inode = cpu_to_le32(inode->i_ino);
		ext3_set_de_type(dir->i_sb, de, inode->i_mode);
	} else
		de->inode = 0;
	de->name_len = namelen;
	memcpy (de->name, name, namelen);
	/*
	 * XXX shouldn't update any times until successful
	 * completion of syscall, but too many callers depend
	 * on this.
	 *
	 * XXX similarly, too many callers depend on
	 * ext3_new_inode() setting the times, but error
	 * recovery deletes the inode, so the worst that can
	 * happen is that the times are slightly out of date
	 * and/or different from the directory change time.
	 */
	dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
	ext3_update_dx_flag(dir);
	dir->i_version++;
	ext3_mark_inode_dirty(handle, dir);
	BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
	err = ext3_journal_dirty_metadata(handle, bh);
	if (err)
		ext3_std_error(dir->i_sb, err);
	brelse(bh);
	return 0;
}

#ifdef CONFIG_EXT3_INDEX
/*
 * This converts a one block unindexed directory to a 3 block indexed
 * directory, and adds the dentry to the indexed directory.
 */
static int make_indexed_dir(handle_t *handle, struct dentry *dentry,
			    struct inode *inode, struct buffer_head *bh)
{
	struct inode	*dir = dentry->d_parent->d_inode;
	const char	*name = dentry->d_name.name;
	int		namelen = dentry->d_name.len;
	struct buffer_head *bh2;
	struct dx_root	*root;
	struct dx_frame	frames[2], *frame;
	struct dx_entry *entries;
	struct ext3_dir_entry_2	*de, *de2;
	char		*data1, *top;
	unsigned	len;
	int		retval;
	unsigned	blocksize;
	struct dx_hash_info hinfo;
	u32		block;
	struct fake_dirent *fde;

	blocksize =  dir->i_sb->s_blocksize;
	dxtrace(printk("Creating index\n"));
	retval = ext3_journal_get_write_access(handle, bh);
	if (retval) {
		ext3_std_error(dir->i_sb, retval);
		brelse(bh);
		return retval;
	}
	root = (struct dx_root *) bh->b_data;

	bh2 = ext3_append (handle, dir, &block, &retval);
	if (!(bh2)) {
		brelse(bh);
		return retval;
	}
	EXT3_I(dir)->i_flags |= EXT3_INDEX_FL;
	data1 = bh2->b_data;

	/* The 0th block becomes the root, move the dirents out */
	fde = &root->dotdot;
	de = (struct ext3_dir_entry_2 *)((char *)fde + le16_to_cpu(fde->rec_len));
	len = ((char *) root) + blocksize - (char *) de;
	memcpy (data1, de, len);
	de = (struct ext3_dir_entry_2 *) data1;
	top = data1 + len;
	while ((char *)(de2=(void*)de+le16_to_cpu(de->rec_len)) < top)
		de = de2;
	de->rec_len = cpu_to_le16(data1 + blocksize - (char *) de);
	/* Initialize the root; the dot dirents already exist */
	de = (struct ext3_dir_entry_2 *) (&root->dotdot);
	de->rec_len = cpu_to_le16(blocksize - EXT3_DIR_REC_LEN(2));
	memset (&root->info, 0, sizeof(root->info));
	root->info.info_length = sizeof(root->info);
	root->info.hash_version = EXT3_SB(dir->i_sb)->s_def_hash_version;
	entries = root->entries;
	dx_set_block (entries, 1);
	dx_set_count (entries, 1);
	dx_set_limit (entries, dx_root_limit(dir, sizeof(root->info)));

	/* Initialize as for dx_probe */
	hinfo.hash_version = root->info.hash_version;
	hinfo.seed = EXT3_SB(dir->i_sb)->s_hash_seed;
	ext3fs_dirhash(name, namelen, &hinfo);
	frame = frames;
	frame->entries = entries;
	frame->at = entries;
	frame->bh = bh;
	bh = bh2;
	de = do_split(handle,dir, &bh, frame, &hinfo, &retval);
	dx_release (frames);
	if (!(de))
		return retval;

	return add_dirent_to_buf(handle, dentry, inode, de, bh);
}
#endif

/*
 *	ext3_add_entry()
 *
 * adds a file entry to the specified directory, using the same
 * semantics as ext3_find_entry(). It returns NULL if it failed.
 *
 * NOTE!! The inode part of 'de' is left at 0 - which means you
 * may not sleep between calling this and putting something into
 * the entry, as someone else might have used it while you slept.
 */
static int ext3_add_entry (handle_t *handle, struct dentry *dentry,
	struct inode *inode)
{
	struct inode *dir = dentry->d_parent->d_inode;
	unsigned long offset;
	struct buffer_head * bh;
	struct ext3_dir_entry_2 *de;
	struct super_block * sb;
	int	retval;
#ifdef CONFIG_EXT3_INDEX
	int	dx_fallback=0;
#endif
	unsigned blocksize;
	unsigned nlen, rlen;
	u32 block, blocks;

	sb = dir->i_sb;
	blocksize = sb->s_blocksize;
	if (!dentry->d_name.len)
		return -EINVAL;
#ifdef CONFIG_EXT3_INDEX
	if (is_dx(dir)) {
		retval = ext3_dx_add_entry(handle, dentry, inode);
		if (!retval || (retval != ERR_BAD_DX_DIR))
			return retval;
		EXT3_I(dir)->i_flags &= ~EXT3_INDEX_FL;
		dx_fallback++;
		ext3_mark_inode_dirty(handle, dir);
	}
#endif
	blocks = dir->i_size >> sb->s_blocksize_bits;
	for (block = 0, offset = 0; block < blocks; block++) {
		bh = ext3_bread(handle, dir, block, 0, &retval);
		if(!bh)
			return retval;
		retval = add_dirent_to_buf(handle, dentry, inode, NULL, bh);
		if (retval != -ENOSPC)
			return retval;

#ifdef CONFIG_EXT3_INDEX
		if (blocks == 1 && !dx_fallback &&
		    EXT3_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_DIR_INDEX))
			return make_indexed_dir(handle, dentry, inode, bh);
#endif
		brelse(bh);
	}
	bh = ext3_append(handle, dir, &block, &retval);
	if (!bh)
		return retval;
	de = (struct ext3_dir_entry_2 *) bh->b_data;
	de->inode = 0;
	de->rec_len = cpu_to_le16(rlen = blocksize);
	nlen = 0;
	return add_dirent_to_buf(handle, dentry, inode, de, bh);
}

#ifdef CONFIG_EXT3_INDEX
/*
 * Returns 0 for success, or a negative error value
 */
static int ext3_dx_add_entry(handle_t *handle, struct dentry *dentry,
			     struct inode *inode)
{
	struct dx_frame frames[2], *frame;
	struct dx_entry *entries, *at;
	struct dx_hash_info hinfo;
	struct buffer_head * bh;
	struct inode *dir = dentry->d_parent->d_inode;
	struct super_block * sb = dir->i_sb;
	struct ext3_dir_entry_2 *de;
	int err;

	frame = dx_probe(dentry, NULL, &hinfo, frames, &err);
	if (!frame)
		return err;
	entries = frame->entries;
	at = frame->at;

	if (!(bh = ext3_bread(handle,dir, dx_get_block(frame->at), 0, &err)))
		goto cleanup;

	BUFFER_TRACE(bh, "get_write_access");
	err = ext3_journal_get_write_access(handle, bh);
	if (err)
		goto journal_error;

	err = add_dirent_to_buf(handle, dentry, inode, NULL, bh);
	if (err != -ENOSPC) {
		bh = NULL;
		goto cleanup;
	}

	/* Block full, should compress but for now just split */
	dxtrace(printk("using %u of %u node entries\n",
		       dx_get_count(entries), dx_get_limit(entries)));
	/* Need to split index? */
	if (dx_get_count(entries) == dx_get_limit(entries)) {
		u32 newblock;
		unsigned icount = dx_get_count(entries);
		int levels = frame - frames;
		struct dx_entry *entries2;
		struct dx_node *node2;
		struct buffer_head *bh2;

		if (levels && (dx_get_count(frames->entries) ==
			       dx_get_limit(frames->entries))) {
			ext3_warning(sb, __FUNCTION__,
				     "Directory index full!");
			err = -ENOSPC;
			goto cleanup;
		}
		bh2 = ext3_append (handle, dir, &newblock, &err);
		if (!(bh2))
			goto cleanup;
		node2 = (struct dx_node *)(bh2->b_data);
		entries2 = node2->entries;
		node2->fake.rec_len = cpu_to_le16(sb->s_blocksize);
		node2->fake.inode = 0;
		BUFFER_TRACE(frame->bh, "get_write_access");
		err = ext3_journal_get_write_access(handle, frame->bh);
		if (err)
			goto journal_error;
		if (levels) {
			unsigned icount1 = icount/2, icount2 = icount - icount1;
			unsigned hash2 = dx_get_hash(entries + icount1);
			dxtrace(printk("Split index %i/%i\n", icount1, icount2));

			BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */
			err = ext3_journal_get_write_access(handle,
							     frames[0].bh);
			if (err)
				goto journal_error;

			memcpy ((char *) entries2, (char *) (entries + icount1),
				icount2 * sizeof(struct dx_entry));
			dx_set_count (entries, icount1);
			dx_set_count (entries2, icount2);
			dx_set_limit (entries2, dx_node_limit(dir));

			/* Which index block gets the new entry? */
			if (at - entries >= icount1) {
				frame->at = at = at - entries - icount1 + entries2;
				frame->entries = entries = entries2;
				swap(frame->bh, bh2);
			}
			dx_insert_block (frames + 0, hash2, newblock);
			dxtrace(dx_show_index ("node", frames[1].entries));
			dxtrace(dx_show_index ("node",
			       ((struct dx_node *) bh2->b_data)->entries));
			err = ext3_journal_dirty_metadata(handle, bh2);
			if (err)
				goto journal_error;
			brelse (bh2);
		} else {
			dxtrace(printk("Creating second level index...\n"));
			memcpy((char *) entries2, (char *) entries,
			       icount * sizeof(struct dx_entry));
			dx_set_limit(entries2, dx_node_limit(dir));

			/* Set up root */
			dx_set_count(entries, 1);
			dx_set_block(entries + 0, newblock);
			((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels = 1;

			/* Add new access path frame */
			frame = frames + 1;
			frame->at = at = at - entries + entries2;
			frame->entries = entries = entries2;
			frame->bh = bh2;
			err = ext3_journal_get_write_access(handle,
							     frame->bh);
			if (err)
				goto journal_error;
		}
		ext3_journal_dirty_metadata(handle, frames[0].bh);
	}
	de = do_split(handle, dir, &bh, frame, &hinfo, &err);
	if (!de)
		goto cleanup;
	err = add_dirent_to_buf(handle, dentry, inode, de, bh);
	bh = NULL;
	goto cleanup;

journal_error:
	ext3_std_error(dir->i_sb, err);
cleanup:
	if (bh)
		brelse(bh);
	dx_release(frames);
	return err;
}
#endif

/*
 * ext3_delete_entry deletes a directory entry by merging it with the
 * previous entry
 */
static int ext3_delete_entry (handle_t *handle, 
			      struct inode * dir,
			      struct ext3_dir_entry_2 * de_del,
			      struct buffer_head * bh)
{
	struct ext3_dir_entry_2 * de, * pde;
	int i;

	i = 0;
	pde = NULL;
	de = (struct ext3_dir_entry_2 *) bh->b_data;
	while (i < bh->b_size) {
		if (!ext3_check_dir_entry("ext3_delete_entry", dir, de, bh, i))
			return -EIO;
		if (de == de_del)  {
			BUFFER_TRACE(bh, "get_write_access");
			ext3_journal_get_write_access(handle, bh);
			if (pde)
				pde->rec_len =
					cpu_to_le16(le16_to_cpu(pde->rec_len) +
						    le16_to_cpu(de->rec_len));
			else
				de->inode = 0;
			dir->i_version++;
			BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata");
			ext3_journal_dirty_metadata(handle, bh);
			return 0;
		}
		i += le16_to_cpu(de->rec_len);
		pde = de;
		de = (struct ext3_dir_entry_2 *)
			((char *) de + le16_to_cpu(de->rec_len));
	}
	return -ENOENT;
}

/*
 * ext3_mark_inode_dirty is somewhat expensive, so unlike ext2 we
 * do not perform it in these functions.  We perform it at the call site,
 * if it is needed.
 */
static inline void ext3_inc_count(handle_t *handle, struct inode *inode)
{
	inode->i_nlink++;
}

static inline void ext3_dec_count(handle_t *handle, struct inode *inode)
{
	inode->i_nlink--;
}

static int ext3_add_nondir(handle_t *handle,
		struct dentry *dentry, struct inode *inode)
{
	int err = ext3_add_entry(handle, dentry, inode);
	if (!err) {
		ext3_mark_inode_dirty(handle, inode);
		d_instantiate(dentry, inode);
		return 0;
	}
	ext3_dec_count(handle, inode);
	iput(inode);
	return err;
}

/*
 * By the time this is called, we already have created
 * the directory cache entry for the new file, but it
 * is so far negative - it has no inode.
 *
 * If the create succeeds, we fill in the inode information
 * with d_instantiate(). 
 */
static int ext3_create (struct inode * dir, struct dentry * dentry, int mode,
		struct nameidata *nd)
{
	handle_t *handle; 
	struct inode * inode;
	int err, retries = 0;

retry:
	handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) +
					EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 +
					2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb));
	if (IS_ERR(handle))
		return PTR_ERR(handle);

	if (IS_DIRSYNC(dir))
		handle->h_sync = 1;

	inode = ext3_new_inode (handle, dir, mode);
	err = PTR_ERR(inode);
	if (!IS_ERR(inode)) {
		inode->i_op = &ext3_file_inode_operations;
		inode->i_fop = &ext3_file_operations;
		ext3_set_aops(inode);
		err = ext3_add_nondir(handle, dentry, inode);
	}
	ext3_journal_stop(handle);
	if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries))
		goto retry;
	return err;
}

static int ext3_mknod (struct inode * dir, struct dentry *dentry,
			int mode, dev_t rdev)
{
	handle_t *handle;
	struct inode *inode;
	int err, retries = 0;

	if (!new_valid_dev(rdev))
		return -EINVAL;

retry:
	handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) +
			 		EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 +
					2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb));
	if (IS_ERR(handle))
		return PTR_ERR(handle);

	if (IS_DIRSYNC(dir))
		handle->h_sync = 1;

	inode = ext3_new_inode (handle, dir, mode);
	err = PTR_ERR(inode);
	if (!IS_ERR(inode)) {
		init_special_inode(inode, inode->i_mode, rdev);
#ifdef CONFIG_EXT3_FS_XATTR
		inode->i_op = &ext3_special_inode_operations;
#endif
		err = ext3_add_nondir(handle, dentry, inode);
	}
	ext3_journal_stop(handle);
	if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries))
		goto retry;
	return err;
}

static int ext3_mkdir(struct inode * dir, struct dentry * dentry, int mode)
{
	handle_t *handle;
	struct inode * inode;
	struct buffer_head * dir_block;
	struct ext3_dir_entry_2 * de;
	int err, retries = 0;

	if (dir->i_nlink >= EXT3_LINK_MAX)
		return -EMLINK;

retry:
	handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) +
					EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 +
					2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb));
	if (IS_ERR(handle))
		return PTR_ERR(handle);

	if (IS_DIRSYNC(dir))
		handle->h_sync = 1;

	inode = ext3_new_inode (handle, dir, S_IFDIR | mode);
	err = PTR_ERR(inode);
	if (IS_ERR(inode))
		goto out_stop;

	inode->i_op = &ext3_dir_inode_operations;
	inode->i_fop = &ext3_dir_operations;
	inode->i_size = EXT3_I(inode)->i_disksize = inode->i_sb->s_blocksize;
	dir_block = ext3_bread (handle, inode, 0, 1, &err);
	if (!dir_block) {
		inode->i_nlink--; /* is this nlink == 0? */
		ext3_mark_inode_dirty(handle, inode);
		iput (inode);
		goto out_stop;
	}
	BUFFER_TRACE(dir_block, "get_write_access");
	ext3_journal_get_write_access(handle, dir_block);
	de = (struct ext3_dir_entry_2 *) dir_block->b_data;
	de->inode = cpu_to_le32(inode->i_ino);
	de->name_len = 1;
	de->rec_len = cpu_to_le16(EXT3_DIR_REC_LEN(de->name_len));
	strcpy (de->name, ".");
	ext3_set_de_type(dir->i_sb, de, S_IFDIR);
	de = (struct ext3_dir_entry_2 *)
			((char *) de + le16_to_cpu(de->rec_len));
	de->inode = cpu_to_le32(dir->i_ino);
	de->rec_len = cpu_to_le16(inode->i_sb->s_blocksize-EXT3_DIR_REC_LEN(1));
	de->name_len = 2;
	strcpy (de->name, "..");
	ext3_set_de_type(dir->i_sb, de, S_IFDIR);
	inode->i_nlink = 2;
	BUFFER_TRACE(dir_block, "call ext3_journal_dirty_metadata");
	ext3_journal_dirty_metadata(handle, dir_block);
	brelse (dir_block);
	ext3_mark_inode_dirty(handle, inode);
	err = ext3_add_entry (handle, dentry, inode);
	if (err) {
		inode->i_nlink = 0;
		ext3_mark_inode_dirty(handle, inode);
		iput (inode);
		goto out_stop;
	}
	dir->i_nlink++;
	ext3_update_dx_flag(dir);
	ext3_mark_inode_dirty(handle, dir);
	d_instantiate(dentry, inode);
out_stop:
	ext3_journal_stop(handle);
	if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries))
		goto retry;
	return err;
}

/*
 * routine to check that the specified directory is empty (for rmdir)
 */
static int empty_dir (struct inode * inode)
{
	unsigned long offset;
	struct buffer_head * bh;
	struct ext3_dir_entry_2 * de, * de1;
	struct super_block * sb;
	int err = 0;

	sb = inode->i_sb;
	if (inode->i_size < EXT3_DIR_REC_LEN(1) + EXT3_DIR_REC_LEN(2) ||
	    !(bh = ext3_bread (NULL, inode, 0, 0, &err))) {
		if (err)
			ext3_error(inode->i_sb, __FUNCTION__,
				   "error %d reading directory #%lu offset 0",
				   err, inode->i_ino);
		else
			ext3_warning(inode->i_sb, __FUNCTION__,
				     "bad directory (dir #%lu) - no data block",
				     inode->i_ino);
		return 1;
	}
	de = (struct ext3_dir_entry_2 *) bh->b_data;
	de1 = (struct ext3_dir_entry_2 *)
			((char *) de + le16_to_cpu(de->rec_len));
	if (le32_to_cpu(de->inode) != inode->i_ino ||
			!le32_to_cpu(de1->inode) || 
			strcmp (".", de->name) ||
			strcmp ("..", de1->name)) {
	    	ext3_warning (inode->i_sb, "empty_dir",
			      "bad directory (dir #%lu) - no `.' or `..'",
			      inode->i_ino);
		brelse (bh);
		return 1;
	}
	offset = le16_to_cpu(de->rec_len) + le16_to_cpu(de1->rec_len);
	de = (struct ext3_dir_entry_2 *)
			((char *) de1 + le16_to_cpu(de1->rec_len));
	while (offset < inode->i_size ) {
		if (!bh ||
			(void *) de >= (void *) (bh->b_data+sb->s_blocksize)) {
			err = 0;
			brelse (bh);
			bh = ext3_bread (NULL, inode,
				offset >> EXT3_BLOCK_SIZE_BITS(sb), 0, &err);
			if (!bh) {
				if (err)
					ext3_error(sb, __FUNCTION__,
						   "error %d reading directory"
						   " #%lu offset %lu",
						   err, inode->i_ino, offset);
				offset += sb->s_blocksize;
				continue;
			}
			de = (struct ext3_dir_entry_2 *) bh->b_data;
		}
		if (!ext3_check_dir_entry("empty_dir", inode, de, bh, offset)) {
			de = (struct ext3_dir_entry_2 *)(bh->b_data +
							 sb->s_blocksize);
			offset = (offset | (sb->s_blocksize - 1)) + 1;
			continue;
		}
		if (le32_to_cpu(de->inode)) {
			brelse (bh);
			return 0;
		}
		offset += le16_to_cpu(de->rec_len);
		de = (struct ext3_dir_entry_2 *)
				((char *) de + le16_to_cpu(de->rec_len));
	}
	brelse (bh);
	return 1;
}

/* ext3_orphan_add() links an unlinked or truncated inode into a list of
 * such inodes, starting at the superblock, in case we crash before the
 * file is closed/deleted, or in case the inode truncate spans multiple
 * transactions and the last transaction is not recovered after a crash.
 *
 * At filesystem recovery time, we walk this list deleting unlinked
 * inodes and truncating linked inodes in ext3_orphan_cleanup().
 */
int ext3_orphan_add(handle_t *handle, struct inode *inode)
{
	struct super_block *sb = inode->i_sb;
	struct ext3_iloc iloc;
	int err = 0, rc;

	lock_super(sb);
	if (!list_empty(&EXT3_I(inode)->i_orphan))
		goto out_unlock;

	/* Orphan handling is only valid for files with data blocks
	 * being truncated, or files being unlinked. */

	/* @@@ FIXME: Observation from aviro:
	 * I think I can trigger J_ASSERT in ext3_orphan_add().  We block 
	 * here (on lock_super()), so race with ext3_link() which might bump
	 * ->i_nlink. For, say it, character device. Not a regular file,
	 * not a directory, not a symlink and ->i_nlink > 0.
	 */
	J_ASSERT ((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
		S_ISLNK(inode->i_mode)) || inode->i_nlink == 0);

	BUFFER_TRACE(EXT3_SB(sb)->s_sbh, "get_write_access");
	err = ext3_journal_get_write_access(handle, EXT3_SB(sb)->s_sbh);
	if (err)
		goto out_unlock;

	err = ext3_reserve_inode_write(handle, inode, &iloc);
	if (err)
		goto out_unlock;

	/* Insert this inode at the head of the on-disk orphan list... */
	NEXT_ORPHAN(inode) = le32_to_cpu(EXT3_SB(sb)->s_es->s_last_orphan);
	EXT3_SB(sb)->s_es->s_last_orphan = cpu_to_le32(inode->i_ino);
	err = ext3_journal_dirty_metadata(handle, EXT3_SB(sb)->s_sbh);
	rc = ext3_mark_iloc_dirty(handle, inode, &iloc);
	if (!err)
		err = rc;

	/* Only add to the head of the in-memory list if all the
	 * previous operations succeeded.  If the orphan_add is going to
	 * fail (possibly taking the journal offline), we can't risk
	 * leaving the inode on the orphan list: stray orphan-list
	 * entries can cause panics at unmount time.
	 *
	 * This is safe: on error we're going to ignore the orphan list
	 * anyway on the next recovery. */
	if (!err)
		list_add(&EXT3_I(inode)->i_orphan, &EXT3_SB(sb)->s_orphan);

	jbd_debug(4, "superblock will point to %ld\n", inode->i_ino);
	jbd_debug(4, "orphan inode %ld will point to %d\n",
			inode->i_ino, NEXT_ORPHAN(inode));
out_unlock:
	unlock_super(sb);
	ext3_std_error(inode->i_sb, err);
	return err;
}

/*
 * ext3_orphan_del() removes an unlinked or truncated inode from the list
 * of such inodes stored on disk, because it is finally being cleaned up.
 */
int ext3_orphan_del(handle_t *handle, struct inode *inode)
{
	struct list_head *prev;
	struct ext3_inode_info *ei = EXT3_I(inode);
	struct ext3_sb_info *sbi;
	unsigned long ino_next;
	struct ext3_iloc iloc;
	int err = 0;

	lock_super(inode->i_sb);
	if (list_empty(&ei->i_orphan)) {
		unlock_super(inode->i_sb);
		return 0;
	}

	ino_next = NEXT_ORPHAN(inode);
	prev = ei->i_orphan.prev;
	sbi = EXT3_SB(inode->i_sb);

	jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino);

	list_del_init(&ei->i_orphan);

	/* If we're on an error path, we may not have a valid
	 * transaction handle with which to update the orphan list on
	 * disk, but we still need to remove the inode from the linked
	 * list in memory. */
	if (!handle)
		goto out;

	err = ext3_reserve_inode_write(handle, inode, &iloc);
	if (err)
		goto out_err;

	if (prev == &sbi->s_orphan) {
		jbd_debug(4, "superblock will point to %lu\n", ino_next);
		BUFFER_TRACE(sbi->s_sbh, "get_write_access");
		err = ext3_journal_get_write_access(handle, sbi->s_sbh);
		if (err)
			goto out_brelse;
		sbi->s_es->s_last_orphan = cpu_to_le32(ino_next);
		err = ext3_journal_dirty_metadata(handle, sbi->s_sbh);
	} else {
		struct ext3_iloc iloc2;
		struct inode *i_prev =
			&list_entry(prev, struct ext3_inode_info, i_orphan)->vfs_inode;

		jbd_debug(4, "orphan inode %lu will point to %lu\n",
			  i_prev->i_ino, ino_next);
		err = ext3_reserve_inode_write(handle, i_prev, &iloc2);
		if (err)
			goto out_brelse;
		NEXT_ORPHAN(i_prev) = ino_next;
		err = ext3_mark_iloc_dirty(handle, i_prev, &iloc2);
	}
	if (err)
		goto out_brelse;
	NEXT_ORPHAN(inode) = 0;
	err = ext3_mark_iloc_dirty(handle, inode, &iloc);

out_err:
	ext3_std_error(inode->i_sb, err);
out:
	unlock_super(inode->i_sb);
	return err;

out_brelse:
	brelse(iloc.bh);
	goto out_err;
}

static int ext3_rmdir (struct inode * dir, struct dentry *dentry)
{
	int retval;
	struct inode * inode;
	struct buffer_head * bh;
	struct ext3_dir_entry_2 * de;
	handle_t *handle;

	/* Initialize quotas before so that eventual writes go in
	 * separate transaction */
	DQUOT_INIT(dentry->d_inode);
	handle = ext3_journal_start(dir, EXT3_DELETE_TRANS_BLOCKS(dir->i_sb));
	if (IS_ERR(handle))
		return PTR_ERR(handle);

	retval = -ENOENT;
	bh = ext3_find_entry (dentry, &de);
	if (!bh)
		goto end_rmdir;

	if (IS_DIRSYNC(dir))
		handle->h_sync = 1;

	inode = dentry->d_inode;

	retval = -EIO;
	if (le32_to_cpu(de->inode) != inode->i_ino)
		goto end_rmdir;

	retval = -ENOTEMPTY;
	if (!empty_dir (inode))
		goto end_rmdir;

	retval = ext3_delete_entry(handle, dir, de, bh);
	if (retval)
		goto end_rmdir;
	if (inode->i_nlink != 2)
		ext3_warning (inode->i_sb, "ext3_rmdir",
			      "empty directory has nlink!=2 (%d)",
			      inode->i_nlink);
	inode->i_version++;
	inode->i_nlink = 0;
	/* There's no need to set i_disksize: the fact that i_nlink is
	 * zero will ensure that the right thing happens during any
	 * recovery. */
	inode->i_size = 0;
	ext3_orphan_add(handle, inode);
	inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC;
	ext3_mark_inode_dirty(handle, inode);
	dir->i_nlink--;
	ext3_update_dx_flag(dir);
	ext3_mark_inode_dirty(handle, dir);

end_rmdir:
	ext3_journal_stop(handle);
	brelse (bh);
	return retval;
}

static int ext3_unlink(struct inode * dir, struct dentry *dentry)
{
	int retval;
	struct inode * inode;
	struct buffer_head * bh;
	struct ext3_dir_entry_2 * de;
	handle_t *handle;

	/* Initialize quotas before so that eventual writes go
	 * in separate transaction */
	DQUOT_INIT(dentry->d_inode);
	handle = ext3_journal_start(dir, EXT3_DELETE_TRANS_BLOCKS(dir->i_sb));
	if (IS_ERR(handle))
		return PTR_ERR(handle);

	if (IS_DIRSYNC(dir))
		handle->h_sync = 1;

	retval = -ENOENT;
	bh = ext3_find_entry (dentry, &de);
	if (!bh)
		goto end_unlink;

	inode = dentry->d_inode;

	retval = -EIO;
	if (le32_to_cpu(de->inode) != inode->i_ino)
		goto end_unlink;

	if (!inode->i_nlink) {
		ext3_warning (inode->i_sb, "ext3_unlink",
			      "Deleting nonexistent file (%lu), %d",
			      inode->i_ino, inode->i_nlink);
		inode->i_nlink = 1;
	}
	retval = ext3_delete_entry(handle, dir, de, bh);
	if (retval)
		goto end_unlink;
	dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC;
	ext3_update_dx_flag(dir);
	ext3_mark_inode_dirty(handle, dir);
	inode->i_nlink--;
	if (!inode->i_nlink)
		ext3_orphan_add(handle, inode);
	inode->i_ctime = dir->i_ctime;
	ext3_mark_inode_dirty(handle, inode);
	retval = 0;

end_unlink:
	ext3_journal_stop(handle);
	brelse (bh);
	return retval;
}

static int ext3_symlink (struct inode * dir,
		struct dentry *dentry, const char * symname)
{
	handle_t *handle;
	struct inode * inode;
	int l, err, retries = 0;

	l = strlen(symname)+1;
	if (l > dir->i_sb->s_blocksize)
		return -ENAMETOOLONG;

retry:
	handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) +
			 		EXT3_INDEX_EXTRA_TRANS_BLOCKS + 5 +
					2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb));
	if (IS_ERR(handle))
		return PTR_ERR(handle);

	if (IS_DIRSYNC(dir))
		handle->h_sync = 1;

	inode = ext3_new_inode (handle, dir, S_IFLNK|S_IRWXUGO);
	err = PTR_ERR(inode);
	if (IS_ERR(inode))
		goto out_stop;

	if (l > sizeof (EXT3_I(inode)->i_data)) {
		inode->i_op = &ext3_symlink_inode_operations;
		ext3_set_aops(inode);
		/*
		 * page_symlink() calls into ext3_prepare/commit_write.
		 * We have a transaction open.  All is sweetness.  It also sets
		 * i_size in generic_commit_write().
		 */
		err = page_symlink(inode, symname, l);
		if (err) {
			ext3_dec_count(handle, inode);
			ext3_mark_inode_dirty(handle, inode);
			iput (inode);
			goto out_stop;
		}
	} else {
		inode->i_op = &ext3_fast_symlink_inode_operations;
		memcpy((char*)&EXT3_I(inode)->i_data,symname,l);
		inode->i_size = l-1;
	}
	EXT3_I(inode)->i_disksize = inode->i_size;
	err = ext3_add_nondir(handle, dentry, inode);
out_stop:
	ext3_journal_stop(handle);
	if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries))
		goto retry;
	return err;
}

static int ext3_link (struct dentry * old_dentry,
		struct inode * dir, struct dentry *dentry)
{
	handle_t *handle;
	struct inode *inode = old_dentry->d_inode;
	int err, retries = 0;

	if (inode->i_nlink >= EXT3_LINK_MAX)
		return -EMLINK;

retry:
	handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) +
					EXT3_INDEX_EXTRA_TRANS_BLOCKS);
	if (IS_ERR(handle))
		return PTR_ERR(handle);

	if (IS_DIRSYNC(dir))
		handle->h_sync = 1;

	inode->i_ctime = CURRENT_TIME_SEC;
	ext3_inc_count(handle, inode);
	atomic_inc(&inode->i_count);

	err = ext3_add_nondir(handle, dentry, inode);
	ext3_journal_stop(handle);
	if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries))
		goto retry;
	return err;
}

#define PARENT_INO(buffer) \
	((struct ext3_dir_entry_2 *) ((char *) buffer + \
	le16_to_cpu(((struct ext3_dir_entry_2 *) buffer)->rec_len)))->inode

/*
 * Anybody can rename anything with this: the permission checks are left to the
 * higher-level routines.
 */
static int ext3_rename (struct inode * old_dir, struct dentry *old_dentry,
			   struct inode * new_dir,struct dentry *new_dentry)
{
	handle_t *handle;
	struct inode * old_inode, * new_inode;
	struct buffer_head * old_bh, * new_bh, * dir_bh;
	struct ext3_dir_entry_2 * old_de, * new_de;
	int retval;

	old_bh = new_bh = dir_bh = NULL;

	/* Initialize quotas before so that eventual writes go
	 * in separate transaction */
	if (new_dentry->d_inode)
		DQUOT_INIT(new_dentry->d_inode);
	handle = ext3_journal_start(old_dir, 2 *
					EXT3_DATA_TRANS_BLOCKS(old_dir->i_sb) +
			 		EXT3_INDEX_EXTRA_TRANS_BLOCKS + 2);
	if (IS_ERR(handle))
		return PTR_ERR(handle);

	if (IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir))
		handle->h_sync = 1;

	old_bh = ext3_find_entry (old_dentry, &old_de);
	/*
	 *  Check for inode number is _not_ due to possible IO errors.
	 *  We might rmdir the source, keep it as pwd of some process
	 *  and merrily kill the link to whatever was created under the
	 *  same name. Goodbye sticky bit ;-<
	 */
	old_inode = old_dentry->d_inode;
	retval = -ENOENT;
	if (!old_bh || le32_to_cpu(old_de->inode) != old_inode->i_ino)
		goto end_rename;

	new_inode = new_dentry->d_inode;
	new_bh = ext3_find_entry (new_dentry, &new_de);
	if (new_bh) {
		if (!new_inode) {
			brelse (new_bh);
			new_bh = NULL;
		}
	}
	if (S_ISDIR(old_inode->i_mode)) {
		if (new_inode) {
			retval = -ENOTEMPTY;
			if (!empty_dir (new_inode))
				goto end_rename;
		}
		retval = -EIO;
		dir_bh = ext3_bread (handle, old_inode, 0, 0, &retval);
		if (!dir_bh)
			goto end_rename;
		if (le32_to_cpu(PARENT_INO(dir_bh->b_data)) != old_dir->i_ino)
			goto end_rename;
		retval = -EMLINK;
		if (!new_inode && new_dir!=old_dir &&
				new_dir->i_nlink >= EXT3_LINK_MAX)
			goto end_rename;
	}
	if (!new_bh) {
		retval = ext3_add_entry (handle, new_dentry, old_inode);
		if (retval)
			goto end_rename;
	} else {
		BUFFER_TRACE(new_bh, "get write access");
		ext3_journal_get_write_access(handle, new_bh);
		new_de->inode = cpu_to_le32(old_inode->i_ino);
		if (EXT3_HAS_INCOMPAT_FEATURE(new_dir->i_sb,
					      EXT3_FEATURE_INCOMPAT_FILETYPE))
			new_de->file_type = old_de->file_type;
		new_dir->i_version++;
		BUFFER_TRACE(new_bh, "call ext3_journal_dirty_metadata");
		ext3_journal_dirty_metadata(handle, new_bh);
		brelse(new_bh);
		new_bh = NULL;
	}

	/*
	 * Like most other Unix systems, set the ctime for inodes on a
	 * rename.
	 */
	old_inode->i_ctime = CURRENT_TIME_SEC;
	ext3_mark_inode_dirty(handle, old_inode);

	/*
	 * ok, that's it
	 */
	if (le32_to_cpu(old_de->inode) != old_inode->i_ino ||
	    old_de->name_len != old_dentry->d_name.len ||
	    strncmp(old_de->name, old_dentry->d_name.name, old_de->name_len) ||
	    (retval = ext3_delete_entry(handle, old_dir,
					old_de, old_bh)) == -ENOENT) {
		/* old_de could have moved from under us during htree split, so
		 * make sure that we are deleting the right entry.  We might
		 * also be pointing to a stale entry in the unused part of
		 * old_bh so just checking inum and the name isn't enough. */
		struct buffer_head *old_bh2;
		struct ext3_dir_entry_2 *old_de2;

		old_bh2 = ext3_find_entry(old_dentry, &old_de2);
		if (old_bh2) {
			retval = ext3_delete_entry(handle, old_dir,
						   old_de2, old_bh2);
			brelse(old_bh2);
		}
	}
	if (retval) {
		ext3_warning(old_dir->i_sb, "ext3_rename",
				"Deleting old file (%lu), %d, error=%d",
				old_dir->i_ino, old_dir->i_nlink, retval);
	}

	if (new_inode) {
		new_inode->i_nlink--;
		new_inode->i_ctime = CURRENT_TIME_SEC;
	}
	old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME_SEC;
	ext3_update_dx_flag(old_dir);
	if (dir_bh) {
		BUFFER_TRACE(dir_bh, "get_write_access");
		ext3_journal_get_write_access(handle, dir_bh);
		PARENT_INO(dir_bh->b_data) = cpu_to_le32(new_dir->i_ino);
		BUFFER_TRACE(dir_bh, "call ext3_journal_dirty_metadata");
		ext3_journal_dirty_metadata(handle, dir_bh);
		old_dir->i_nlink--;
		if (new_inode) {
			new_inode->i_nlink--;
		} else {
			new_dir->i_nlink++;
			ext3_update_dx_flag(new_dir);
			ext3_mark_inode_dirty(handle, new_dir);
		}
	}
	ext3_mark_inode_dirty(handle, old_dir);
	if (new_inode) {
		ext3_mark_inode_dirty(handle, new_inode);
		if (!new_inode->i_nlink)
			ext3_orphan_add(handle, new_inode);
	}
	retval = 0;

end_rename:
	brelse (dir_bh);
	brelse (old_bh);
	brelse (new_bh);
	ext3_journal_stop(handle);
	return retval;
}

/*
 * directories can handle most operations...
 */
struct inode_operations ext3_dir_inode_operations = {
	.create		= ext3_create,
	.lookup		= ext3_lookup,
	.link		= ext3_link,
	.unlink		= ext3_unlink,
	.symlink	= ext3_symlink,
	.mkdir		= ext3_mkdir,
	.rmdir		= ext3_rmdir,
	.mknod		= ext3_mknod,
	.rename		= ext3_rename,
	.setattr	= ext3_setattr,
#ifdef CONFIG_EXT3_FS_XATTR
	.setxattr	= generic_setxattr,
	.getxattr	= generic_getxattr,
	.listxattr	= ext3_listxattr,
	.removexattr	= generic_removexattr,
#endif
	.permission	= ext3_permission,
};

struct inode_operations ext3_special_inode_operations = {
	.setattr	= ext3_setattr,
#ifdef CONFIG_EXT3_FS_XATTR
	.setxattr	= generic_setxattr,
	.getxattr	= generic_getxattr,
	.listxattr	= ext3_listxattr,
	.removexattr	= generic_removexattr,
#endif
	.permission	= ext3_permission,
};