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Merge branch 'for-3.16-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj...
[linux-2.6/btrfs-unstable.git] / fs / xfs / xfs_dir2.c
blob79670cda48ae4797f902af912d59d105215885bb
1 /*
2 * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18 #include "xfs.h"
19 #include "xfs_fs.h"
20 #include "xfs_format.h"
21 #include "xfs_log_format.h"
22 #include "xfs_trans_resv.h"
23 #include "xfs_inum.h"
24 #include "xfs_sb.h"
25 #include "xfs_ag.h"
26 #include "xfs_mount.h"
27 #include "xfs_da_format.h"
28 #include "xfs_da_btree.h"
29 #include "xfs_inode.h"
30 #include "xfs_trans.h"
31 #include "xfs_inode_item.h"
32 #include "xfs_bmap.h"
33 #include "xfs_dir2.h"
34 #include "xfs_dir2_priv.h"
35 #include "xfs_error.h"
36 #include "xfs_trace.h"
37 #include "xfs_dinode.h"
38
39 struct xfs_name xfs_name_dotdot = { (unsigned char *)"..", 2, XFS_DIR3_FT_DIR };
40
41
42 /*
43 * ASCII case-insensitive (ie. A-Z) support for directories that was
44 * used in IRIX.
45 */
46 STATIC xfs_dahash_t
47 xfs_ascii_ci_hashname(
48 struct xfs_name *name)
49 {
50 xfs_dahash_t hash;
51 int i;
52
53 for (i = 0, hash = 0; i < name->len; i++)
54 hash = tolower(name->name[i]) ^ rol32(hash, 7);
55
56 return hash;
57 }
58
59 STATIC enum xfs_dacmp
60 xfs_ascii_ci_compname(
61 struct xfs_da_args *args,
62 const unsigned char *name,
63 int len)
64 {
65 enum xfs_dacmp result;
66 int i;
67
68 if (args->namelen != len)
69 return XFS_CMP_DIFFERENT;
70
71 result = XFS_CMP_EXACT;
72 for (i = 0; i < len; i++) {
73 if (args->name[i] == name[i])
74 continue;
75 if (tolower(args->name[i]) != tolower(name[i]))
76 return XFS_CMP_DIFFERENT;
77 result = XFS_CMP_CASE;
78 }
79
80 return result;
81 }
82
83 static struct xfs_nameops xfs_ascii_ci_nameops = {
84 .hashname = xfs_ascii_ci_hashname,
85 .compname = xfs_ascii_ci_compname,
86 };
87
88 int
89 xfs_da_mount(
90 struct xfs_mount *mp)
91 {
92 struct xfs_da_geometry *dageo;
93 int nodehdr_size;
94
95
96 ASSERT(mp->m_sb.sb_versionnum & XFS_SB_VERSION_DIRV2BIT);
97 ASSERT((1 << (mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog)) <=
98 XFS_MAX_BLOCKSIZE);
99
100 mp->m_dir_inode_ops = xfs_dir_get_ops(mp, NULL);
101 mp->m_nondir_inode_ops = xfs_nondir_get_ops(mp, NULL);
102
103 nodehdr_size = mp->m_dir_inode_ops->node_hdr_size;
104 mp->m_dir_geo = kmem_zalloc(sizeof(struct xfs_da_geometry),
105 KM_SLEEP | KM_MAYFAIL);
106 mp->m_attr_geo = kmem_zalloc(sizeof(struct xfs_da_geometry),
107 KM_SLEEP | KM_MAYFAIL);
108 if (!mp->m_dir_geo || !mp->m_attr_geo) {
109 kmem_free(mp->m_dir_geo);
110 kmem_free(mp->m_attr_geo);
111 return ENOMEM;
112 }
113
114 /* set up directory geometry */
115 dageo = mp->m_dir_geo;
116 dageo->blklog = mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog;
117 dageo->fsblog = mp->m_sb.sb_blocklog;
118 dageo->blksize = 1 << dageo->blklog;
119 dageo->fsbcount = 1 << mp->m_sb.sb_dirblklog;
120
121 /*
122 * Now we've set up the block conversion variables, we can calculate the
123 * segment block constants using the geometry structure.
124 */
125 dageo->datablk = xfs_dir2_byte_to_da(dageo, XFS_DIR2_DATA_OFFSET);
126 dageo->leafblk = xfs_dir2_byte_to_da(dageo, XFS_DIR2_LEAF_OFFSET);
127 dageo->freeblk = xfs_dir2_byte_to_da(dageo, XFS_DIR2_FREE_OFFSET);
128 dageo->node_ents = (dageo->blksize - nodehdr_size) /
129 (uint)sizeof(xfs_da_node_entry_t);
130 dageo->magicpct = (dageo->blksize * 37) / 100;
131
132 /* set up attribute geometry - single fsb only */
133 dageo = mp->m_attr_geo;
134 dageo->blklog = mp->m_sb.sb_blocklog;
135 dageo->fsblog = mp->m_sb.sb_blocklog;
136 dageo->blksize = 1 << dageo->blklog;
137 dageo->fsbcount = 1;
138 dageo->node_ents = (dageo->blksize - nodehdr_size) /
139 (uint)sizeof(xfs_da_node_entry_t);
140 dageo->magicpct = (dageo->blksize * 37) / 100;
141
142 if (xfs_sb_version_hasasciici(&mp->m_sb))
143 mp->m_dirnameops = &xfs_ascii_ci_nameops;
144 else
145 mp->m_dirnameops = &xfs_default_nameops;
146
147 return 0;
148 }
149
150 void
151 xfs_da_unmount(
152 struct xfs_mount *mp)
153 {
154 kmem_free(mp->m_dir_geo);
155 kmem_free(mp->m_attr_geo);
156 }
157
158 /*
159 * Return 1 if directory contains only "." and "..".
160 */
161 int
162 xfs_dir_isempty(
163 xfs_inode_t *dp)
164 {
165 xfs_dir2_sf_hdr_t *sfp;
166
167 ASSERT(S_ISDIR(dp->i_d.di_mode));
168 if (dp->i_d.di_size == 0) /* might happen during shutdown. */
169 return 1;
170 if (dp->i_d.di_size > XFS_IFORK_DSIZE(dp))
171 return 0;
172 sfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
173 return !sfp->count;
174 }
175
176 /*
177 * Validate a given inode number.
178 */
179 int
180 xfs_dir_ino_validate(
181 xfs_mount_t *mp,
182 xfs_ino_t ino)
183 {
184 xfs_agblock_t agblkno;
185 xfs_agino_t agino;
186 xfs_agnumber_t agno;
187 int ino_ok;
188 int ioff;
189
190 agno = XFS_INO_TO_AGNO(mp, ino);
191 agblkno = XFS_INO_TO_AGBNO(mp, ino);
192 ioff = XFS_INO_TO_OFFSET(mp, ino);
193 agino = XFS_OFFBNO_TO_AGINO(mp, agblkno, ioff);
194 ino_ok =
195 agno < mp->m_sb.sb_agcount &&
196 agblkno < mp->m_sb.sb_agblocks &&
197 agblkno != 0 &&
198 ioff < (1 << mp->m_sb.sb_inopblog) &&
199 XFS_AGINO_TO_INO(mp, agno, agino) == ino;
200 if (unlikely(XFS_TEST_ERROR(!ino_ok, mp, XFS_ERRTAG_DIR_INO_VALIDATE,
201 XFS_RANDOM_DIR_INO_VALIDATE))) {
202 xfs_warn(mp, "Invalid inode number 0x%Lx",
203 (unsigned long long) ino);
204 XFS_ERROR_REPORT("xfs_dir_ino_validate", XFS_ERRLEVEL_LOW, mp);
205 return XFS_ERROR(EFSCORRUPTED);
206 }
207 return 0;
208 }
209
210 /*
211 * Initialize a directory with its "." and ".." entries.
212 */
213 int
214 xfs_dir_init(
215 xfs_trans_t *tp,
216 xfs_inode_t *dp,
217 xfs_inode_t *pdp)
218 {
219 struct xfs_da_args *args;
220 int error;
221
222 ASSERT(S_ISDIR(dp->i_d.di_mode));
223 error = xfs_dir_ino_validate(tp->t_mountp, pdp->i_ino);
224 if (error)
225 return error;
226
227 args = kmem_zalloc(sizeof(*args), KM_SLEEP | KM_NOFS);
228 if (!args)
229 return ENOMEM;
230
231 args->geo = dp->i_mount->m_dir_geo;
232 args->dp = dp;
233 args->trans = tp;
234 error = xfs_dir2_sf_create(args, pdp->i_ino);
235 kmem_free(args);
236 return error;
237 }
238
239 /*
240 Enter a name in a directory.
241 */
242 int
243 xfs_dir_createname(
244 xfs_trans_t *tp,
245 xfs_inode_t *dp,
246 struct xfs_name *name,
247 xfs_ino_t inum, /* new entry inode number */
248 xfs_fsblock_t *first, /* bmap's firstblock */
249 xfs_bmap_free_t *flist, /* bmap's freeblock list */
250 xfs_extlen_t total) /* bmap's total block count */
251 {
252 struct xfs_da_args *args;
253 int rval;
254 int v; /* type-checking value */
255
256 ASSERT(S_ISDIR(dp->i_d.di_mode));
257 rval = xfs_dir_ino_validate(tp->t_mountp, inum);
258 if (rval)
259 return rval;
260 XFS_STATS_INC(xs_dir_create);
261
262 args = kmem_zalloc(sizeof(*args), KM_SLEEP | KM_NOFS);
263 if (!args)
264 return ENOMEM;
265
266 args->geo = dp->i_mount->m_dir_geo;
267 args->name = name->name;
268 args->namelen = name->len;
269 args->filetype = name->type;
270 args->hashval = dp->i_mount->m_dirnameops->hashname(name);
271 args->inumber = inum;
272 args->dp = dp;
273 args->firstblock = first;
274 args->flist = flist;
275 args->total = total;
276 args->whichfork = XFS_DATA_FORK;
277 args->trans = tp;
278 args->op_flags = XFS_DA_OP_ADDNAME | XFS_DA_OP_OKNOENT;
279
280 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL) {
281 rval = xfs_dir2_sf_addname(args);
282 goto out_free;
283 }
284
285 rval = xfs_dir2_isblock(args, &v);
286 if (rval)
287 goto out_free;
288 if (v) {
289 rval = xfs_dir2_block_addname(args);
290 goto out_free;
291 }
292
293 rval = xfs_dir2_isleaf(args, &v);
294 if (rval)
295 goto out_free;
296 if (v)
297 rval = xfs_dir2_leaf_addname(args);
298 else
299 rval = xfs_dir2_node_addname(args);
300
301 out_free:
302 kmem_free(args);
303 return rval;
304 }
305
306 /*
307 * If doing a CI lookup and case-insensitive match, dup actual name into
308 * args.value. Return EEXIST for success (ie. name found) or an error.
309 */
310 int
311 xfs_dir_cilookup_result(
312 struct xfs_da_args *args,
313 const unsigned char *name,
314 int len)
315 {
316 if (args->cmpresult == XFS_CMP_DIFFERENT)
317 return ENOENT;
318 if (args->cmpresult != XFS_CMP_CASE ||
319 !(args->op_flags & XFS_DA_OP_CILOOKUP))
320 return EEXIST;
321
322 args->value = kmem_alloc(len, KM_NOFS | KM_MAYFAIL);
323 if (!args->value)
324 return ENOMEM;
325
326 memcpy(args->value, name, len);
327 args->valuelen = len;
328 return EEXIST;
329 }
330
331 /*
332 * Lookup a name in a directory, give back the inode number.
333 * If ci_name is not NULL, returns the actual name in ci_name if it differs
334 * to name, or ci_name->name is set to NULL for an exact match.
335 */
336
337 int
338 xfs_dir_lookup(
339 xfs_trans_t *tp,
340 xfs_inode_t *dp,
341 struct xfs_name *name,
342 xfs_ino_t *inum, /* out: inode number */
343 struct xfs_name *ci_name) /* out: actual name if CI match */
344 {
345 struct xfs_da_args *args;
346 int rval;
347 int v; /* type-checking value */
348
349 ASSERT(S_ISDIR(dp->i_d.di_mode));
350 XFS_STATS_INC(xs_dir_lookup);
351
352 /*
353 * We need to use KM_NOFS here so that lockdep will not throw false
354 * positive deadlock warnings on a non-transactional lookup path. It is
355 * safe to recurse into inode recalim in that case, but lockdep can't
356 * easily be taught about it. Hence KM_NOFS avoids having to add more
357 * lockdep Doing this avoids having to add a bunch of lockdep class
358 * annotations into the reclaim path for the ilock.
359 */
360 args = kmem_zalloc(sizeof(*args), KM_SLEEP | KM_NOFS);
361 args->geo = dp->i_mount->m_dir_geo;
362 args->name = name->name;
363 args->namelen = name->len;
364 args->filetype = name->type;
365 args->hashval = dp->i_mount->m_dirnameops->hashname(name);
366 args->dp = dp;
367 args->whichfork = XFS_DATA_FORK;
368 args->trans = tp;
369 args->op_flags = XFS_DA_OP_OKNOENT;
370 if (ci_name)
371 args->op_flags |= XFS_DA_OP_CILOOKUP;
372
373 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL) {
374 rval = xfs_dir2_sf_lookup(args);
375 goto out_check_rval;
376 }
377
378 rval = xfs_dir2_isblock(args, &v);
379 if (rval)
380 goto out_free;
381 if (v) {
382 rval = xfs_dir2_block_lookup(args);
383 goto out_check_rval;
384 }
385
386 rval = xfs_dir2_isleaf(args, &v);
387 if (rval)
388 goto out_free;
389 if (v)
390 rval = xfs_dir2_leaf_lookup(args);
391 else
392 rval = xfs_dir2_node_lookup(args);
393
394 out_check_rval:
395 if (rval == EEXIST)
396 rval = 0;
397 if (!rval) {
398 *inum = args->inumber;
399 if (ci_name) {
400 ci_name->name = args->value;
401 ci_name->len = args->valuelen;
402 }
403 }
404 out_free:
405 kmem_free(args);
406 return rval;
407 }
408
409 /*
410 * Remove an entry from a directory.
411 */
412 int
413 xfs_dir_removename(
414 xfs_trans_t *tp,
415 xfs_inode_t *dp,
416 struct xfs_name *name,
417 xfs_ino_t ino,
418 xfs_fsblock_t *first, /* bmap's firstblock */
419 xfs_bmap_free_t *flist, /* bmap's freeblock list */
420 xfs_extlen_t total) /* bmap's total block count */
421 {
422 struct xfs_da_args *args;
423 int rval;
424 int v; /* type-checking value */
425
426 ASSERT(S_ISDIR(dp->i_d.di_mode));
427 XFS_STATS_INC(xs_dir_remove);
428
429 args = kmem_zalloc(sizeof(*args), KM_SLEEP | KM_NOFS);
430 if (!args)
431 return ENOMEM;
432
433 args->geo = dp->i_mount->m_dir_geo;
434 args->name = name->name;
435 args->namelen = name->len;
436 args->filetype = name->type;
437 args->hashval = dp->i_mount->m_dirnameops->hashname(name);
438 args->inumber = ino;
439 args->dp = dp;
440 args->firstblock = first;
441 args->flist = flist;
442 args->total = total;
443 args->whichfork = XFS_DATA_FORK;
444 args->trans = tp;
445
446 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL) {
447 rval = xfs_dir2_sf_removename(args);
448 goto out_free;
449 }
450
451 rval = xfs_dir2_isblock(args, &v);
452 if (rval)
453 goto out_free;
454 if (v) {
455 rval = xfs_dir2_block_removename(args);
456 goto out_free;
457 }
458
459 rval = xfs_dir2_isleaf(args, &v);
460 if (rval)
461 goto out_free;
462 if (v)
463 rval = xfs_dir2_leaf_removename(args);
464 else
465 rval = xfs_dir2_node_removename(args);
466 out_free:
467 kmem_free(args);
468 return rval;
469 }
470
471 /*
472 * Replace the inode number of a directory entry.
473 */
474 int
475 xfs_dir_replace(
476 xfs_trans_t *tp,
477 xfs_inode_t *dp,
478 struct xfs_name *name, /* name of entry to replace */
479 xfs_ino_t inum, /* new inode number */
480 xfs_fsblock_t *first, /* bmap's firstblock */
481 xfs_bmap_free_t *flist, /* bmap's freeblock list */
482 xfs_extlen_t total) /* bmap's total block count */
483 {
484 struct xfs_da_args *args;
485 int rval;
486 int v; /* type-checking value */
487
488 ASSERT(S_ISDIR(dp->i_d.di_mode));
489
490 rval = xfs_dir_ino_validate(tp->t_mountp, inum);
491 if (rval)
492 return rval;
493
494 args = kmem_zalloc(sizeof(*args), KM_SLEEP | KM_NOFS);
495 if (!args)
496 return ENOMEM;
497
498 args->geo = dp->i_mount->m_dir_geo;
499 args->name = name->name;
500 args->namelen = name->len;
501 args->filetype = name->type;
502 args->hashval = dp->i_mount->m_dirnameops->hashname(name);
503 args->inumber = inum;
504 args->dp = dp;
505 args->firstblock = first;
506 args->flist = flist;
507 args->total = total;
508 args->whichfork = XFS_DATA_FORK;
509 args->trans = tp;
510
511 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL) {
512 rval = xfs_dir2_sf_replace(args);
513 goto out_free;
514 }
515
516 rval = xfs_dir2_isblock(args, &v);
517 if (rval)
518 goto out_free;
519 if (v) {
520 rval = xfs_dir2_block_replace(args);
521 goto out_free;
522 }
523
524 rval = xfs_dir2_isleaf(args, &v);
525 if (rval)
526 goto out_free;
527 if (v)
528 rval = xfs_dir2_leaf_replace(args);
529 else
530 rval = xfs_dir2_node_replace(args);
531 out_free:
532 kmem_free(args);
533 return rval;
534 }
535
536 /*
537 * See if this entry can be added to the directory without allocating space.
538 * First checks that the caller couldn't reserve enough space (resblks = 0).
539 */
540 int
541 xfs_dir_canenter(
542 xfs_trans_t *tp,
543 xfs_inode_t *dp,
544 struct xfs_name *name, /* name of entry to add */
545 uint resblks)
546 {
547 struct xfs_da_args *args;
548 int rval;
549 int v; /* type-checking value */
550
551 if (resblks)
552 return 0;
553
554 ASSERT(S_ISDIR(dp->i_d.di_mode));
555
556 args = kmem_zalloc(sizeof(*args), KM_SLEEP | KM_NOFS);
557 if (!args)
558 return ENOMEM;
559
560 args->geo = dp->i_mount->m_dir_geo;
561 args->name = name->name;
562 args->namelen = name->len;
563 args->filetype = name->type;
564 args->hashval = dp->i_mount->m_dirnameops->hashname(name);
565 args->dp = dp;
566 args->whichfork = XFS_DATA_FORK;
567 args->trans = tp;
568 args->op_flags = XFS_DA_OP_JUSTCHECK | XFS_DA_OP_ADDNAME |
569 XFS_DA_OP_OKNOENT;
570
571 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL) {
572 rval = xfs_dir2_sf_addname(args);
573 goto out_free;
574 }
575
576 rval = xfs_dir2_isblock(args, &v);
577 if (rval)
578 goto out_free;
579 if (v) {
580 rval = xfs_dir2_block_addname(args);
581 goto out_free;
582 }
583
584 rval = xfs_dir2_isleaf(args, &v);
585 if (rval)
586 goto out_free;
587 if (v)
588 rval = xfs_dir2_leaf_addname(args);
589 else
590 rval = xfs_dir2_node_addname(args);
591 out_free:
592 kmem_free(args);
593 return rval;
594 }
595
596 /*
597 * Utility routines.
598 */
599
600 /*
601 * Add a block to the directory.
602 *
603 * This routine is for data and free blocks, not leaf/node blocks which are
604 * handled by xfs_da_grow_inode.
605 */
606 int
607 xfs_dir2_grow_inode(
608 struct xfs_da_args *args,
609 int space, /* v2 dir's space XFS_DIR2_xxx_SPACE */
610 xfs_dir2_db_t *dbp) /* out: block number added */
611 {
612 struct xfs_inode *dp = args->dp;
613 struct xfs_mount *mp = dp->i_mount;
614 xfs_fileoff_t bno; /* directory offset of new block */
615 int count; /* count of filesystem blocks */
616 int error;
617
618 trace_xfs_dir2_grow_inode(args, space);
619
620 /*
621 * Set lowest possible block in the space requested.
622 */
623 bno = XFS_B_TO_FSBT(mp, space * XFS_DIR2_SPACE_SIZE);
624 count = args->geo->fsbcount;
625
626 error = xfs_da_grow_inode_int(args, &bno, count);
627 if (error)
628 return error;
629
630 *dbp = xfs_dir2_da_to_db(args->geo, (xfs_dablk_t)bno);
631
632 /*
633 * Update file's size if this is the data space and it grew.
634 */
635 if (space == XFS_DIR2_DATA_SPACE) {
636 xfs_fsize_t size; /* directory file (data) size */
637
638 size = XFS_FSB_TO_B(mp, bno + count);
639 if (size > dp->i_d.di_size) {
640 dp->i_d.di_size = size;
641 xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE);
642 }
643 }
644 return 0;
645 }
646
647 /*
648 * See if the directory is a single-block form directory.
649 */
650 int
651 xfs_dir2_isblock(
652 struct xfs_da_args *args,
653 int *vp) /* out: 1 is block, 0 is not block */
654 {
655 xfs_fileoff_t last; /* last file offset */
656 int rval;
657
658 if ((rval = xfs_bmap_last_offset(args->dp, &last, XFS_DATA_FORK)))
659 return rval;
660 rval = XFS_FSB_TO_B(args->dp->i_mount, last) == args->geo->blksize;
661 ASSERT(rval == 0 || args->dp->i_d.di_size == args->geo->blksize);
662 *vp = rval;
663 return 0;
664 }
665
666 /*
667 * See if the directory is a single-leaf form directory.
668 */
669 int
670 xfs_dir2_isleaf(
671 struct xfs_da_args *args,
672 int *vp) /* out: 1 is block, 0 is not block */
673 {
674 xfs_fileoff_t last; /* last file offset */
675 int rval;
676
677 if ((rval = xfs_bmap_last_offset(args->dp, &last, XFS_DATA_FORK)))
678 return rval;
679 *vp = last == args->geo->leafblk + args->geo->fsbcount;
680 return 0;
681 }
682
683 /*
684 * Remove the given block from the directory.
685 * This routine is used for data and free blocks, leaf/node are done
686 * by xfs_da_shrink_inode.
687 */
688 int
689 xfs_dir2_shrink_inode(
690 xfs_da_args_t *args,
691 xfs_dir2_db_t db,
692 struct xfs_buf *bp)
693 {
694 xfs_fileoff_t bno; /* directory file offset */
695 xfs_dablk_t da; /* directory file offset */
696 int done; /* bunmap is finished */
697 xfs_inode_t *dp;
698 int error;
699 xfs_mount_t *mp;
700 xfs_trans_t *tp;
701
702 trace_xfs_dir2_shrink_inode(args, db);
703
704 dp = args->dp;
705 mp = dp->i_mount;
706 tp = args->trans;
707 da = xfs_dir2_db_to_da(args->geo, db);
708 /*
709 * Unmap the fsblock(s).
710 */
711 if ((error = xfs_bunmapi(tp, dp, da, args->geo->fsbcount,
712 XFS_BMAPI_METADATA, 0, args->firstblock, args->flist,
713 &done))) {
714 /*
715 * ENOSPC actually can happen if we're in a removename with
716 * no space reservation, and the resulting block removal
717 * would cause a bmap btree split or conversion from extents
718 * to btree. This can only happen for un-fragmented
719 * directory blocks, since you need to be punching out
720 * the middle of an extent.
721 * In this case we need to leave the block in the file,
722 * and not binval it.
723 * So the block has to be in a consistent empty state
724 * and appropriately logged.
725 * We don't free up the buffer, the caller can tell it
726 * hasn't happened since it got an error back.
727 */
728 return error;
729 }
730 ASSERT(done);
731 /*
732 * Invalidate the buffer from the transaction.
733 */
734 xfs_trans_binval(tp, bp);
735 /*
736 * If it's not a data block, we're done.
737 */
738 if (db >= xfs_dir2_byte_to_db(args->geo, XFS_DIR2_LEAF_OFFSET))
739 return 0;
740 /*
741 * If the block isn't the last one in the directory, we're done.
742 */
743 if (dp->i_d.di_size > xfs_dir2_db_off_to_byte(args->geo, db + 1, 0))
744 return 0;
745 bno = da;
746 if ((error = xfs_bmap_last_before(tp, dp, &bno, XFS_DATA_FORK))) {
747 /*
748 * This can't really happen unless there's kernel corruption.
749 */
750 return error;
751 }
752 if (db == args->geo->datablk)
753 ASSERT(bno == 0);
754 else
755 ASSERT(bno > 0);
756 /*
757 * Set the size to the new last block.
758 */
759 dp->i_d.di_size = XFS_FSB_TO_B(mp, bno);
760 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
761 return 0;
762 }
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