summaryrefslogtreecommitdiffstats
path: root/fs/xfs/xfs_dir2.c
blob: 1afb12278b8d04b85eb42d0f67d0bd21936885be (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
/*
 * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
 * All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it would be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write the Free Software Foundation,
 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_types.h"
#include "xfs_bit.h"
#include "xfs_log.h"
#include "xfs_inum.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_dir2.h"
#include "xfs_dmapi.h"
#include "xfs_mount.h"
#include "xfs_da_btree.h"
#include "xfs_bmap_btree.h"
#include "xfs_alloc_btree.h"
#include "xfs_dir2_sf.h"
#include "xfs_attr_sf.h"
#include "xfs_dinode.h"
#include "xfs_inode.h"
#include "xfs_inode_item.h"
#include "xfs_bmap.h"
#include "xfs_dir2_data.h"
#include "xfs_dir2_leaf.h"
#include "xfs_dir2_block.h"
#include "xfs_dir2_node.h"
#include "xfs_dir2_trace.h"
#include "xfs_error.h"
#include "xfs_vnodeops.h"

struct xfs_name xfs_name_dotdot = {"..", 2};

extern const struct xfs_nameops xfs_default_nameops;

/*
 * ASCII case-insensitive (ie. A-Z) support for directories that was
 * used in IRIX.
 */
STATIC xfs_dahash_t
xfs_ascii_ci_hashname(
	struct xfs_name	*name)
{
	xfs_dahash_t	hash;
	int		i;

	for (i = 0, hash = 0; i < name->len; i++)
		hash = tolower(name->name[i]) ^ rol32(hash, 7);

	return hash;
}

STATIC enum xfs_dacmp
xfs_ascii_ci_compname(
	struct xfs_da_args *args,
	const char	*name,
	int 		len)
{
	enum xfs_dacmp	result;
	int		i;

	if (args->namelen != len)
		return XFS_CMP_DIFFERENT;

	result = XFS_CMP_EXACT;
	for (i = 0; i < len; i++) {
		if (args->name[i] == name[i])
			continue;
		if (tolower(args->name[i]) != tolower(name[i]))
			return XFS_CMP_DIFFERENT;
		result = XFS_CMP_CASE;
	}

	return result;
}

static struct xfs_nameops xfs_ascii_ci_nameops = {
	.hashname	= xfs_ascii_ci_hashname,
	.compname	= xfs_ascii_ci_compname,
};

void
xfs_dir_mount(
	xfs_mount_t	*mp)
{
	ASSERT(xfs_sb_version_hasdirv2(&mp->m_sb));
	ASSERT((1 << (mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog)) <=
	       XFS_MAX_BLOCKSIZE);
	mp->m_dirblksize = 1 << (mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog);
	mp->m_dirblkfsbs = 1 << mp->m_sb.sb_dirblklog;
	mp->m_dirdatablk = xfs_dir2_db_to_da(mp, XFS_DIR2_DATA_FIRSTDB(mp));
	mp->m_dirleafblk = xfs_dir2_db_to_da(mp, XFS_DIR2_LEAF_FIRSTDB(mp));
	mp->m_dirfreeblk = xfs_dir2_db_to_da(mp, XFS_DIR2_FREE_FIRSTDB(mp));
	mp->m_attr_node_ents =
		(mp->m_sb.sb_blocksize - (uint)sizeof(xfs_da_node_hdr_t)) /
		(uint)sizeof(xfs_da_node_entry_t);
	mp->m_dir_node_ents =
		(mp->m_dirblksize - (uint)sizeof(xfs_da_node_hdr_t)) /
		(uint)sizeof(xfs_da_node_entry_t);
	mp->m_dir_magicpct = (mp->m_dirblksize * 37) / 100;
	if (xfs_sb_version_hasasciici(&mp->m_sb))
		mp->m_dirnameops = &xfs_ascii_ci_nameops;
	else
		mp->m_dirnameops = &xfs_default_nameops;
}

/*
 * Return 1 if directory contains only "." and "..".
 */
int
xfs_dir_isempty(
	xfs_inode_t	*dp)
{
	xfs_dir2_sf_t	*sfp;

	ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
	if (dp->i_d.di_size == 0)	/* might happen during shutdown. */
		return 1;
	if (dp->i_d.di_size > XFS_IFORK_DSIZE(dp))
		return 0;
	sfp = (xfs_dir2_sf_t *)dp->i_df.if_u1.if_data;
	return !sfp->hdr.count;
}

/*
 * Validate a given inode number.
 */
int
xfs_dir_ino_validate(
	xfs_mount_t	*mp,
	xfs_ino_t	ino)
{
	xfs_agblock_t	agblkno;
	xfs_agino_t	agino;
	xfs_agnumber_t	agno;
	int		ino_ok;
	int		ioff;

	agno = XFS_INO_TO_AGNO(mp, ino);
	agblkno = XFS_INO_TO_AGBNO(mp, ino);
	ioff = XFS_INO_TO_OFFSET(mp, ino);
	agino = XFS_OFFBNO_TO_AGINO(mp, agblkno, ioff);
	ino_ok =
		agno < mp->m_sb.sb_agcount &&
		agblkno < mp->m_sb.sb_agblocks &&
		agblkno != 0 &&
		ioff < (1 << mp->m_sb.sb_inopblog) &&
		XFS_AGINO_TO_INO(mp, agno, agino) == ino;
	if (unlikely(XFS_TEST_ERROR(!ino_ok, mp, XFS_ERRTAG_DIR_INO_VALIDATE,
			XFS_RANDOM_DIR_INO_VALIDATE))) {
		xfs_fs_cmn_err(CE_WARN, mp, "Invalid inode number 0x%Lx",
				(unsigned long long) ino);
		XFS_ERROR_REPORT("xfs_dir_ino_validate", XFS_ERRLEVEL_LOW, mp);
		return XFS_ERROR(EFSCORRUPTED);
	}
	return 0;
}

/*
 * Initialize a directory with its "." and ".." entries.
 */
int
xfs_dir_init(
	xfs_trans_t	*tp,
	xfs_inode_t	*dp,
	xfs_inode_t	*pdp)
{
	xfs_da_args_t	args;
	int		error;

	memset((char *)&args, 0, sizeof(args));
	args.dp = dp;
	args.trans = tp;
	ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
	if ((error = xfs_dir_ino_validate(tp->t_mountp, pdp->i_ino)))
		return error;
	return xfs_dir2_sf_create(&args, pdp->i_ino);
}

/*
  Enter a name in a directory.
 */
int
xfs_dir_createname(
	xfs_trans_t		*tp,
	xfs_inode_t		*dp,
	struct xfs_name		*name,
	xfs_ino_t		inum,		/* new entry inode number */
	xfs_fsblock_t		*first,		/* bmap's firstblock */
	xfs_bmap_free_t		*flist,		/* bmap's freeblock list */
	xfs_extlen_t		total)		/* bmap's total block count */
{
	xfs_da_args_t		args;
	int			rval;
	int			v;		/* type-checking value */

	ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
	if ((rval = xfs_dir_ino_validate(tp->t_mountp, inum)))
		return rval;
	XFS_STATS_INC(xs_dir_create);

	memset(&args, 0, sizeof(xfs_da_args_t));
	args.name = name->name;
	args.namelen = name->len;
	args.hashval = dp->i_mount->m_dirnameops->hashname(name);
	args.inumber = inum;
	args.dp = dp;
	args.firstblock = first;
	args.flist = flist;
	args.total = total;
	args.whichfork = XFS_DATA_FORK;
	args.trans = tp;
	args.op_flags = XFS_DA_OP_ADDNAME | XFS_DA_OP_OKNOENT;

	if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
		rval = xfs_dir2_sf_addname(&args);
	else if ((rval = xfs_dir2_isblock(tp, dp, &v)))
		return rval;
	else if (v)
		rval = xfs_dir2_block_addname(&args);
	else if ((rval = xfs_dir2_isleaf(tp, dp, &v)))
		return rval;
	else if (v)
		rval = xfs_dir2_leaf_addname(&args);
	else
		rval = xfs_dir2_node_addname(&args);
	return rval;
}

/*
 * If doing a CI lookup and case-insensitive match, dup actual name into
 * args.value. Return EEXIST for success (ie. name found) or an error.
 */
int
xfs_dir_cilookup_result(
	struct xfs_da_args *args,
	const char	*name,
	int		len)
{
	if (args->cmpresult == XFS_CMP_DIFFERENT)
		return ENOENT;
	if (args->cmpresult != XFS_CMP_CASE ||
					!(args->op_flags & XFS_DA_OP_CILOOKUP))
		return EEXIST;

	args->value = kmem_alloc(len, KM_MAYFAIL);
	if (!args->value)
		return ENOMEM;

	memcpy(args->value, name, len);
	args->valuelen = len;
	return EEXIST;
}

/*
 * Lookup a name in a directory, give back the inode number.
 * If ci_name is not NULL, returns the actual name in ci_name if it differs
 * to name, or ci_name->name is set to NULL for an exact match.
 */

int
xfs_dir_lookup(
	xfs_trans_t	*tp,
	xfs_inode_t	*dp,
	struct xfs_name	*name,
	xfs_ino_t	*inum,		/* out: inode number */
	struct xfs_name *ci_name)	/* out: actual name if CI match */
{
	xfs_da_args_t	args;
	int		rval;
	int		v;		/* type-checking value */

	ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
	XFS_STATS_INC(xs_dir_lookup);

	memset(&args, 0, sizeof(xfs_da_args_t));
	args.name = name->name;
	args.namelen = name->len;
	args.hashval = dp->i_mount->m_dirnameops->hashname(name);
	args.dp = dp;
	args.whichfork = XFS_DATA_FORK;
	args.trans = tp;
	args.op_flags = XFS_DA_OP_OKNOENT;
	if (ci_name)
		args.op_flags |= XFS_DA_OP_CILOOKUP;

	if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
		rval = xfs_dir2_sf_lookup(&args);
	else if ((rval = xfs_dir2_isblock(tp, dp, &v)))
		return rval;
	else if (v)
		rval = xfs_dir2_block_lookup(&args);
	else if ((rval = xfs_dir2_isleaf(tp, dp, &v)))
		return rval;
	else if (v)
		rval = xfs_dir2_leaf_lookup(&args);
	else
		rval = xfs_dir2_node_lookup(&args);
	if (rval == EEXIST)
		rval = 0;
	if (!rval) {
		*inum = args.inumber;
		if (ci_name) {
			ci_name->name = args.value;
			ci_name->len = args.valuelen;
		}
	}
	return rval;
}

/*
 * Remove an entry from a directory.
 */
int
xfs_dir_removename(
	xfs_trans_t	*tp,
	xfs_inode_t	*dp,
	struct xfs_name	*name,
	xfs_ino_t	ino,
	xfs_fsblock_t	*first,		/* bmap's firstblock */
	xfs_bmap_free_t	*flist,		/* bmap's freeblock list */
	xfs_extlen_t	total)		/* bmap's total block count */
{
	xfs_da_args_t	args;
	int		rval;
	int		v;		/* type-checking value */

	ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
	XFS_STATS_INC(xs_dir_remove);

	memset(&args, 0, sizeof(xfs_da_args_t));
	args.name = name->name;
	args.namelen = name->len;
	args.hashval = dp->i_mount->m_dirnameops->hashname(name);
	args.inumber = ino;
	args.dp = dp;
	args.firstblock = first;
	args.flist = flist;
	args.total = total;
	args.whichfork = XFS_DATA_FORK;
	args.trans = tp;

	if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
		rval = xfs_dir2_sf_removename(&args);
	else if ((rval = xfs_dir2_isblock(tp, dp, &v)))
		return rval;
	else if (v)
		rval = xfs_dir2_block_removename(&args);
	else if ((rval = xfs_dir2_isleaf(tp, dp, &v)))
		return rval;
	else if (v)
		rval = xfs_dir2_leaf_removename(&args);
	else
		rval = xfs_dir2_node_removename(&args);
	return rval;
}

/*
 * Read a directory.
 */
int
xfs_readdir(
	xfs_inode_t	*dp,
	void		*dirent,
	size_t		bufsize,
	xfs_off_t	*offset,
	filldir_t	filldir)
{
	int		rval;		/* return value */
	int		v;		/* type-checking value */

	xfs_itrace_entry(dp);

	if (XFS_FORCED_SHUTDOWN(dp->i_mount))
		return XFS_ERROR(EIO);

	ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
	XFS_STATS_INC(xs_dir_getdents);

	if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
		rval = xfs_dir2_sf_getdents(dp, dirent, offset, filldir);
	else if ((rval = xfs_dir2_isblock(NULL, dp, &v)))
		;
	else if (v)
		rval = xfs_dir2_block_getdents(dp, dirent, offset, filldir);
	else
		rval = xfs_dir2_leaf_getdents(dp, dirent, bufsize, offset,
					      filldir);
	return rval;
}

/*
 * Replace the inode number of a directory entry.
 */
int
xfs_dir_replace(
	xfs_trans_t	*tp,
	xfs_inode_t	*dp,
	struct xfs_name	*name,		/* name of entry to replace */
	xfs_ino_t	inum,		/* new inode number */
	xfs_fsblock_t	*first,		/* bmap's firstblock */
	xfs_bmap_free_t	*flist,		/* bmap's freeblock list */
	xfs_extlen_t	total)		/* bmap's total block count */
{
	xfs_da_args_t	args;
	int		rval;
	int		v;		/* type-checking value */

	ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);

	if ((rval = xfs_dir_ino_validate(tp->t_mountp, inum)))
		return rval;

	memset(&args, 0, sizeof(xfs_da_args_t));
	args.name = name->name;
	args.namelen = name->len;
	args.hashval = dp->i_mount->m_dirnameops->hashname(name);
	args.inumber = inum;
	args.dp = dp;
	args.firstblock = first;
	args.flist = flist;
	args.total = total;
	args.whichfork = XFS_DATA_FORK;
	args.trans = tp;

	if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
		rval = xfs_dir2_sf_replace(&args);
	else if ((rval = xfs_dir2_isblock(tp, dp, &v)))
		return rval;
	else if (v)
		rval = xfs_dir2_block_replace(&args);
	else if ((rval = xfs_dir2_isleaf(tp, dp, &v)))
		return rval;
	else if (v)
		rval = xfs_dir2_leaf_replace(&args);
	else
		rval = xfs_dir2_node_replace(&args);
	return rval;
}

/*
 * See if this entry can be added to the directory without allocating space.
 * First checks that the caller couldn't reserve enough space (resblks = 0).
 */
int
xfs_dir_canenter(
	xfs_trans_t	*tp,
	xfs_inode_t	*dp,
	struct xfs_name	*name,		/* name of entry to add */
	uint		resblks)
{
	xfs_da_args_t	args;
	int		rval;
	int		v;		/* type-checking value */

	if (resblks)
		return 0;

	ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);

	memset(&args, 0, sizeof(xfs_da_args_t));
	args.name = name->name;
	args.namelen = name->len;
	args.hashval = dp->i_mount->m_dirnameops->hashname(name);
	args.dp = dp;
	args.whichfork = XFS_DATA_FORK;
	args.trans = tp;
	args.op_flags = XFS_DA_OP_JUSTCHECK | XFS_DA_OP_ADDNAME |
							XFS_DA_OP_OKNOENT;

	if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
		rval = xfs_dir2_sf_addname(&args);
	else if ((rval = xfs_dir2_isblock(tp, dp, &v)))
		return rval;
	else if (v)
		rval = xfs_dir2_block_addname(&args);
	else if ((rval = xfs_dir2_isleaf(tp, dp, &v)))
		return rval;
	else if (v)
		rval = xfs_dir2_leaf_addname(&args);
	else
		rval = xfs_dir2_node_addname(&args);
	return rval;
}

/*
 * Utility routines.
 */

/*
 * Add a block to the directory.
 * This routine is for data and free blocks, not leaf/node blocks
 * which are handled by xfs_da_grow_inode.
 */
int
xfs_dir2_grow_inode(
	xfs_da_args_t	*args,
	int		space,		/* v2 dir's space XFS_DIR2_xxx_SPACE */
	xfs_dir2_db_t	*dbp)		/* out: block number added */
{
	xfs_fileoff_t	bno;		/* directory offset of new block */
	int		count;		/* count of filesystem blocks */
	xfs_inode_t	*dp;		/* incore directory inode */
	int		error;
	int		got;		/* blocks actually mapped */
	int		i;
	xfs_bmbt_irec_t	map;		/* single structure for bmap */
	int		mapi;		/* mapping index */
	xfs_bmbt_irec_t	*mapp;		/* bmap mapping structure(s) */
	xfs_mount_t	*mp;
	int		nmap;		/* number of bmap entries */
	xfs_trans_t	*tp;
	xfs_drfsbno_t	nblks;

	xfs_dir2_trace_args_s("grow_inode", args, space);
	dp = args->dp;
	tp = args->trans;
	mp = dp->i_mount;
	nblks = dp->i_d.di_nblocks;
	/*
	 * Set lowest possible block in the space requested.
	 */
	bno = XFS_B_TO_FSBT(mp, space * XFS_DIR2_SPACE_SIZE);
	count = mp->m_dirblkfsbs;
	/*
	 * Find the first hole for our block.
	 */
	if ((error = xfs_bmap_first_unused(tp, dp, count, &bno, XFS_DATA_FORK)))
		return error;
	nmap = 1;
	ASSERT(args->firstblock != NULL);
	/*
	 * Try mapping the new block contiguously (one extent).
	 */
	if ((error = xfs_bmapi(tp, dp, bno, count,
			XFS_BMAPI_WRITE|XFS_BMAPI_METADATA|XFS_BMAPI_CONTIG,
			args->firstblock, args->total, &map, &nmap,
			args->flist, NULL)))
		return error;
	ASSERT(nmap <= 1);
	if (nmap == 1) {
		mapp = &map;
		mapi = 1;
	}
	/*
	 * Didn't work and this is a multiple-fsb directory block.
	 * Try again with contiguous flag turned on.
	 */
	else if (nmap == 0 && count > 1) {
		xfs_fileoff_t	b;	/* current file offset */

		/*
		 * Space for maximum number of mappings.
		 */
		mapp = kmem_alloc(sizeof(*mapp) * count, KM_SLEEP);
		/*
		 * Iterate until we get to the end of our block.
		 */
		for (b = bno, mapi = 0; b < bno + count; ) {
			int	c;	/* current fsb count */

			/*
			 * Can't map more than MAX_NMAP at once.
			 */
			nmap = MIN(XFS_BMAP_MAX_NMAP, count);
			c = (int)(bno + count - b);
			if ((error = xfs_bmapi(tp, dp, b, c,
					XFS_BMAPI_WRITE|XFS_BMAPI_METADATA,
					args->firstblock, args->total,
					&mapp[mapi], &nmap, args->flist,
					NULL))) {
				kmem_free(mapp);
				return error;
			}
			if (nmap < 1)
				break;
			/*
			 * Add this bunch into our table, go to the next offset.
			 */
			mapi += nmap;
			b = mapp[mapi - 1].br_startoff +
			    mapp[mapi - 1].br_blockcount;
		}
	}
	/*
	 * Didn't work.
	 */
	else {
		mapi = 0;
		mapp = NULL;
	}
	/*
	 * See how many fsb's we got.
	 */
	for (i = 0, got = 0; i < mapi; i++)
		got += mapp[i].br_blockcount;
	/*
	 * Didn't get enough fsb's, or the first/last block's are wrong.
	 */
	if (got != count || mapp[0].br_startoff != bno ||
	    mapp[mapi - 1].br_startoff + mapp[mapi - 1].br_blockcount !=
	    bno + count) {
		if (mapp != &map)
			kmem_free(mapp);
		return XFS_ERROR(ENOSPC);
	}
	/*
	 * Done with the temporary mapping table.
	 */
	if (mapp != &map)
		kmem_free(mapp);

	/* account for newly allocated blocks in reserved blocks total */
	args->total -= dp->i_d.di_nblocks - nblks;
	*dbp = xfs_dir2_da_to_db(mp, (xfs_dablk_t)bno);

	/*
	 * Update file's size if this is the data space and it grew.
	 */
	if (space == XFS_DIR2_DATA_SPACE) {
		xfs_fsize_t	size;		/* directory file (data) size */

		size = XFS_FSB_TO_B(mp, bno + count);
		if (size > dp->i_d.di_size) {
			dp->i_d.di_size = size;
			xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
		}
	}
	return 0;
}

/*
 * See if the directory is a single-block form directory.
 */
int
xfs_dir2_isblock(
	xfs_trans_t	*tp,
	xfs_inode_t	*dp,
	int		*vp)		/* out: 1 is block, 0 is not block */
{
	xfs_fileoff_t	last;		/* last file offset */
	xfs_mount_t	*mp;
	int		rval;

	mp = dp->i_mount;
	if ((rval = xfs_bmap_last_offset(tp, dp, &last, XFS_DATA_FORK)))
		return rval;
	rval = XFS_FSB_TO_B(mp, last) == mp->m_dirblksize;
	ASSERT(rval == 0 || dp->i_d.di_size == mp->m_dirblksize);
	*vp = rval;
	return 0;
}

/*
 * See if the directory is a single-leaf form directory.
 */
int
xfs_dir2_isleaf(
	xfs_trans_t	*tp,
	xfs_inode_t	*dp,
	int		*vp)		/* out: 1 is leaf, 0 is not leaf */
{
	xfs_fileoff_t	last;		/* last file offset */
	xfs_mount_t	*mp;
	int		rval;

	mp = dp->i_mount;
	if ((rval = xfs_bmap_last_offset(tp, dp, &last, XFS_DATA_FORK)))
		return rval;
	*vp = last == mp->m_dirleafblk + (1 << mp->m_sb.sb_dirblklog);
	return 0;
}

/*
 * Remove the given block from the directory.
 * This routine is used for data and free blocks, leaf/node are done
 * by xfs_da_shrink_inode.
 */
int
xfs_dir2_shrink_inode(
	xfs_da_args_t	*args,
	xfs_dir2_db_t	db,
	xfs_dabuf_t	*bp)
{
	xfs_fileoff_t	bno;		/* directory file offset */
	xfs_dablk_t	da;		/* directory file offset */
	int		done;		/* bunmap is finished */
	xfs_inode_t	*dp;
	int		error;
	xfs_mount_t	*mp;
	xfs_trans_t	*tp;

	xfs_dir2_trace_args_db("shrink_inode", args, db, bp);
	dp = args->dp;
	mp = dp->i_mount;
	tp = args->trans;
	da = xfs_dir2_db_to_da(mp, db);
	/*
	 * Unmap the fsblock(s).
	 */
	if ((error = xfs_bunmapi(tp, dp, da, mp->m_dirblkfsbs,
			XFS_BMAPI_METADATA, 0, args->firstblock, args->flist,
			NULL, &done))) {
		/*
		 * ENOSPC actually can happen if we're in a removename with
		 * no space reservation, and the resulting block removal
		 * would cause a bmap btree split or conversion from extents
		 * to btree.  This can only happen for un-fragmented
		 * directory blocks, since you need to be punching out
		 * the middle of an extent.
		 * In this case we need to leave the block in the file,
		 * and not binval it.
		 * So the block has to be in a consistent empty state
		 * and appropriately logged.
		 * We don't free up the buffer, the caller can tell it
		 * hasn't happened since it got an error back.
		 */
		return error;
	}
	ASSERT(done);
	/*
	 * Invalidate the buffer from the transaction.
	 */
	xfs_da_binval(tp, bp);
	/*
	 * If it's not a data block, we're done.
	 */
	if (db >= XFS_DIR2_LEAF_FIRSTDB(mp))
		return 0;
	/*
	 * If the block isn't the last one in the directory, we're done.
	 */
	if (dp->i_d.di_size > xfs_dir2_db_off_to_byte(mp, db + 1, 0))
		return 0;
	bno = da;
	if ((error = xfs_bmap_last_before(tp, dp, &bno, XFS_DATA_FORK))) {
		/*
		 * This can't really happen unless there's kernel corruption.
		 */
		return error;
	}
	if (db == mp->m_dirdatablk)
		ASSERT(bno == 0);
	else
		ASSERT(bno > 0);
	/*
	 * Set the size to the new last block.
	 */
	dp->i_d.di_size = XFS_FSB_TO_B(mp, bno);
	xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
	return 0;
}