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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
4 * All Rights Reserved.
5 */
6#include "xfs.h"
7#include "xfs_fs.h"
8#include "xfs_shared.h"
9#include "xfs_format.h"
10#include "xfs_log_format.h"
11#include "xfs_trans_resv.h"
12#include "xfs_mount.h"
13#include "xfs_inode.h"
14#include "xfs_trans.h"
15#include "xfs_bmap.h"
16#include "xfs_dir2.h"
17#include "xfs_dir2_priv.h"
18#include "xfs_errortag.h"
19#include "xfs_error.h"
20#include "xfs_trace.h"
21
22const struct xfs_name xfs_name_dotdot = {
23 .name = (const unsigned char *)"..",
24 .len = 2,
25 .type = XFS_DIR3_FT_DIR,
26};
27
28/*
29 * Convert inode mode to directory entry filetype
30 */
31unsigned char
32xfs_mode_to_ftype(
33 int mode)
34{
35 switch (mode & S_IFMT) {
36 case S_IFREG:
37 return XFS_DIR3_FT_REG_FILE;
38 case S_IFDIR:
39 return XFS_DIR3_FT_DIR;
40 case S_IFCHR:
41 return XFS_DIR3_FT_CHRDEV;
42 case S_IFBLK:
43 return XFS_DIR3_FT_BLKDEV;
44 case S_IFIFO:
45 return XFS_DIR3_FT_FIFO;
46 case S_IFSOCK:
47 return XFS_DIR3_FT_SOCK;
48 case S_IFLNK:
49 return XFS_DIR3_FT_SYMLINK;
50 default:
51 return XFS_DIR3_FT_UNKNOWN;
52 }
53}
54
55/*
56 * ASCII case-insensitive (ie. A-Z) support for directories that was
57 * used in IRIX.
58 */
59xfs_dahash_t
60xfs_ascii_ci_hashname(
61 const struct xfs_name *name)
62{
63 xfs_dahash_t hash;
64 int i;
65
66 for (i = 0, hash = 0; i < name->len; i++)
67 hash = xfs_ascii_ci_xfrm(name->name[i]) ^ rol32(hash, 7);
68
69 return hash;
70}
71
72enum xfs_dacmp
73xfs_ascii_ci_compname(
74 struct xfs_da_args *args,
75 const unsigned char *name,
76 int len)
77{
78 enum xfs_dacmp result;
79 int i;
80
81 if (args->namelen != len)
82 return XFS_CMP_DIFFERENT;
83
84 result = XFS_CMP_EXACT;
85 for (i = 0; i < len; i++) {
86 if (args->name[i] == name[i])
87 continue;
88 if (xfs_ascii_ci_xfrm(args->name[i]) !=
89 xfs_ascii_ci_xfrm(name[i]))
90 return XFS_CMP_DIFFERENT;
91 result = XFS_CMP_CASE;
92 }
93
94 return result;
95}
96
97int
98xfs_da_mount(
99 struct xfs_mount *mp)
100{
101 struct xfs_da_geometry *dageo;
102
103
104 ASSERT(mp->m_sb.sb_versionnum & XFS_SB_VERSION_DIRV2BIT);
105 ASSERT(xfs_dir2_dirblock_bytes(&mp->m_sb) <= XFS_MAX_BLOCKSIZE);
106
107 mp->m_dir_geo = kmem_zalloc(sizeof(struct xfs_da_geometry),
108 KM_MAYFAIL);
109 mp->m_attr_geo = kmem_zalloc(sizeof(struct xfs_da_geometry),
110 KM_MAYFAIL);
111 if (!mp->m_dir_geo || !mp->m_attr_geo) {
112 kmem_free(mp->m_dir_geo);
113 kmem_free(mp->m_attr_geo);
114 return -ENOMEM;
115 }
116
117 /* set up directory geometry */
118 dageo = mp->m_dir_geo;
119 dageo->blklog = mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog;
120 dageo->fsblog = mp->m_sb.sb_blocklog;
121 dageo->blksize = xfs_dir2_dirblock_bytes(&mp->m_sb);
122 dageo->fsbcount = 1 << mp->m_sb.sb_dirblklog;
123 if (xfs_has_crc(mp)) {
124 dageo->node_hdr_size = sizeof(struct xfs_da3_node_hdr);
125 dageo->leaf_hdr_size = sizeof(struct xfs_dir3_leaf_hdr);
126 dageo->free_hdr_size = sizeof(struct xfs_dir3_free_hdr);
127 dageo->data_entry_offset =
128 sizeof(struct xfs_dir3_data_hdr);
129 } else {
130 dageo->node_hdr_size = sizeof(struct xfs_da_node_hdr);
131 dageo->leaf_hdr_size = sizeof(struct xfs_dir2_leaf_hdr);
132 dageo->free_hdr_size = sizeof(struct xfs_dir2_free_hdr);
133 dageo->data_entry_offset =
134 sizeof(struct xfs_dir2_data_hdr);
135 }
136 dageo->leaf_max_ents = (dageo->blksize - dageo->leaf_hdr_size) /
137 sizeof(struct xfs_dir2_leaf_entry);
138 dageo->free_max_bests = (dageo->blksize - dageo->free_hdr_size) /
139 sizeof(xfs_dir2_data_off_t);
140
141 dageo->data_first_offset = dageo->data_entry_offset +
142 xfs_dir2_data_entsize(mp, 1) +
143 xfs_dir2_data_entsize(mp, 2);
144
145 /*
146 * Now we've set up the block conversion variables, we can calculate the
147 * segment block constants using the geometry structure.
148 */
149 dageo->datablk = xfs_dir2_byte_to_da(dageo, XFS_DIR2_DATA_OFFSET);
150 dageo->leafblk = xfs_dir2_byte_to_da(dageo, XFS_DIR2_LEAF_OFFSET);
151 dageo->freeblk = xfs_dir2_byte_to_da(dageo, XFS_DIR2_FREE_OFFSET);
152 dageo->node_ents = (dageo->blksize - dageo->node_hdr_size) /
153 (uint)sizeof(xfs_da_node_entry_t);
154 dageo->max_extents = (XFS_DIR2_MAX_SPACES * XFS_DIR2_SPACE_SIZE) >>
155 mp->m_sb.sb_blocklog;
156 dageo->magicpct = (dageo->blksize * 37) / 100;
157
158 /* set up attribute geometry - single fsb only */
159 dageo = mp->m_attr_geo;
160 dageo->blklog = mp->m_sb.sb_blocklog;
161 dageo->fsblog = mp->m_sb.sb_blocklog;
162 dageo->blksize = 1 << dageo->blklog;
163 dageo->fsbcount = 1;
164 dageo->node_hdr_size = mp->m_dir_geo->node_hdr_size;
165 dageo->node_ents = (dageo->blksize - dageo->node_hdr_size) /
166 (uint)sizeof(xfs_da_node_entry_t);
167
168 if (xfs_has_large_extent_counts(mp))
169 dageo->max_extents = XFS_MAX_EXTCNT_ATTR_FORK_LARGE;
170 else
171 dageo->max_extents = XFS_MAX_EXTCNT_ATTR_FORK_SMALL;
172
173 dageo->magicpct = (dageo->blksize * 37) / 100;
174 return 0;
175}
176
177void
178xfs_da_unmount(
179 struct xfs_mount *mp)
180{
181 kmem_free(mp->m_dir_geo);
182 kmem_free(mp->m_attr_geo);
183}
184
185/*
186 * Return 1 if directory contains only "." and "..".
187 */
188int
189xfs_dir_isempty(
190 xfs_inode_t *dp)
191{
192 xfs_dir2_sf_hdr_t *sfp;
193
194 ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
195 if (dp->i_disk_size == 0) /* might happen during shutdown. */
196 return 1;
197 if (dp->i_disk_size > xfs_inode_data_fork_size(dp))
198 return 0;
199 sfp = dp->i_df.if_data;
200 return !sfp->count;
201}
202
203/*
204 * Validate a given inode number.
205 */
206int
207xfs_dir_ino_validate(
208 xfs_mount_t *mp,
209 xfs_ino_t ino)
210{
211 bool ino_ok = xfs_verify_dir_ino(mp, ino);
212
213 if (XFS_IS_CORRUPT(mp, !ino_ok) ||
214 XFS_TEST_ERROR(false, mp, XFS_ERRTAG_DIR_INO_VALIDATE)) {
215 xfs_warn(mp, "Invalid inode number 0x%Lx",
216 (unsigned long long) ino);
217 return -EFSCORRUPTED;
218 }
219 return 0;
220}
221
222/*
223 * Initialize a directory with its "." and ".." entries.
224 */
225int
226xfs_dir_init(
227 xfs_trans_t *tp,
228 xfs_inode_t *dp,
229 xfs_inode_t *pdp)
230{
231 struct xfs_da_args *args;
232 int error;
233
234 ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
235 error = xfs_dir_ino_validate(tp->t_mountp, pdp->i_ino);
236 if (error)
237 return error;
238
239 args = kmem_zalloc(sizeof(*args), KM_NOFS);
240 if (!args)
241 return -ENOMEM;
242
243 args->geo = dp->i_mount->m_dir_geo;
244 args->dp = dp;
245 args->trans = tp;
246 error = xfs_dir2_sf_create(args, pdp->i_ino);
247 kmem_free(args);
248 return error;
249}
250
251/*
252 * Enter a name in a directory, or check for available space.
253 * If inum is 0, only the available space test is performed.
254 */
255int
256xfs_dir_createname(
257 struct xfs_trans *tp,
258 struct xfs_inode *dp,
259 const struct xfs_name *name,
260 xfs_ino_t inum, /* new entry inode number */
261 xfs_extlen_t total) /* bmap's total block count */
262{
263 struct xfs_da_args *args;
264 int rval;
265 bool v;
266
267 ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
268
269 if (inum) {
270 rval = xfs_dir_ino_validate(tp->t_mountp, inum);
271 if (rval)
272 return rval;
273 XFS_STATS_INC(dp->i_mount, xs_dir_create);
274 }
275
276 args = kmem_zalloc(sizeof(*args), KM_NOFS);
277 if (!args)
278 return -ENOMEM;
279
280 args->geo = dp->i_mount->m_dir_geo;
281 args->name = name->name;
282 args->namelen = name->len;
283 args->filetype = name->type;
284 args->hashval = xfs_dir2_hashname(dp->i_mount, name);
285 args->inumber = inum;
286 args->dp = dp;
287 args->total = total;
288 args->whichfork = XFS_DATA_FORK;
289 args->trans = tp;
290 args->op_flags = XFS_DA_OP_ADDNAME | XFS_DA_OP_OKNOENT;
291 if (!inum)
292 args->op_flags |= XFS_DA_OP_JUSTCHECK;
293
294 if (dp->i_df.if_format == XFS_DINODE_FMT_LOCAL) {
295 rval = xfs_dir2_sf_addname(args);
296 goto out_free;
297 }
298
299 rval = xfs_dir2_isblock(args, &v);
300 if (rval)
301 goto out_free;
302 if (v) {
303 rval = xfs_dir2_block_addname(args);
304 goto out_free;
305 }
306
307 rval = xfs_dir2_isleaf(args, &v);
308 if (rval)
309 goto out_free;
310 if (v)
311 rval = xfs_dir2_leaf_addname(args);
312 else
313 rval = xfs_dir2_node_addname(args);
314
315out_free:
316 kmem_free(args);
317 return rval;
318}
319
320/*
321 * If doing a CI lookup and case-insensitive match, dup actual name into
322 * args.value. Return EEXIST for success (ie. name found) or an error.
323 */
324int
325xfs_dir_cilookup_result(
326 struct xfs_da_args *args,
327 const unsigned char *name,
328 int len)
329{
330 if (args->cmpresult == XFS_CMP_DIFFERENT)
331 return -ENOENT;
332 if (args->cmpresult != XFS_CMP_CASE ||
333 !(args->op_flags & XFS_DA_OP_CILOOKUP))
334 return -EEXIST;
335
336 args->value = kmem_alloc(len, KM_NOFS | KM_MAYFAIL);
337 if (!args->value)
338 return -ENOMEM;
339
340 memcpy(args->value, name, len);
341 args->valuelen = len;
342 return -EEXIST;
343}
344
345/*
346 * Lookup a name in a directory, give back the inode number.
347 * If ci_name is not NULL, returns the actual name in ci_name if it differs
348 * to name, or ci_name->name is set to NULL for an exact match.
349 */
350
351int
352xfs_dir_lookup(
353 struct xfs_trans *tp,
354 struct xfs_inode *dp,
355 const struct xfs_name *name,
356 xfs_ino_t *inum, /* out: inode number */
357 struct xfs_name *ci_name) /* out: actual name if CI match */
358{
359 struct xfs_da_args *args;
360 int rval;
361 bool v;
362 int lock_mode;
363
364 ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
365 XFS_STATS_INC(dp->i_mount, xs_dir_lookup);
366
367 /*
368 * We need to use KM_NOFS here so that lockdep will not throw false
369 * positive deadlock warnings on a non-transactional lookup path. It is
370 * safe to recurse into inode recalim in that case, but lockdep can't
371 * easily be taught about it. Hence KM_NOFS avoids having to add more
372 * lockdep Doing this avoids having to add a bunch of lockdep class
373 * annotations into the reclaim path for the ilock.
374 */
375 args = kmem_zalloc(sizeof(*args), KM_NOFS);
376 args->geo = dp->i_mount->m_dir_geo;
377 args->name = name->name;
378 args->namelen = name->len;
379 args->filetype = name->type;
380 args->hashval = xfs_dir2_hashname(dp->i_mount, name);
381 args->dp = dp;
382 args->whichfork = XFS_DATA_FORK;
383 args->trans = tp;
384 args->op_flags = XFS_DA_OP_OKNOENT;
385 if (ci_name)
386 args->op_flags |= XFS_DA_OP_CILOOKUP;
387
388 lock_mode = xfs_ilock_data_map_shared(dp);
389 if (dp->i_df.if_format == XFS_DINODE_FMT_LOCAL) {
390 rval = xfs_dir2_sf_lookup(args);
391 goto out_check_rval;
392 }
393
394 rval = xfs_dir2_isblock(args, &v);
395 if (rval)
396 goto out_free;
397 if (v) {
398 rval = xfs_dir2_block_lookup(args);
399 goto out_check_rval;
400 }
401
402 rval = xfs_dir2_isleaf(args, &v);
403 if (rval)
404 goto out_free;
405 if (v)
406 rval = xfs_dir2_leaf_lookup(args);
407 else
408 rval = xfs_dir2_node_lookup(args);
409
410out_check_rval:
411 if (rval == -EEXIST)
412 rval = 0;
413 if (!rval) {
414 *inum = args->inumber;
415 if (ci_name) {
416 ci_name->name = args->value;
417 ci_name->len = args->valuelen;
418 }
419 }
420out_free:
421 xfs_iunlock(dp, lock_mode);
422 kmem_free(args);
423 return rval;
424}
425
426/*
427 * Remove an entry from a directory.
428 */
429int
430xfs_dir_removename(
431 struct xfs_trans *tp,
432 struct xfs_inode *dp,
433 struct xfs_name *name,
434 xfs_ino_t ino,
435 xfs_extlen_t total) /* bmap's total block count */
436{
437 struct xfs_da_args *args;
438 int rval;
439 bool v;
440
441 ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
442 XFS_STATS_INC(dp->i_mount, xs_dir_remove);
443
444 args = kmem_zalloc(sizeof(*args), KM_NOFS);
445 if (!args)
446 return -ENOMEM;
447
448 args->geo = dp->i_mount->m_dir_geo;
449 args->name = name->name;
450 args->namelen = name->len;
451 args->filetype = name->type;
452 args->hashval = xfs_dir2_hashname(dp->i_mount, name);
453 args->inumber = ino;
454 args->dp = dp;
455 args->total = total;
456 args->whichfork = XFS_DATA_FORK;
457 args->trans = tp;
458
459 if (dp->i_df.if_format == XFS_DINODE_FMT_LOCAL) {
460 rval = xfs_dir2_sf_removename(args);
461 goto out_free;
462 }
463
464 rval = xfs_dir2_isblock(args, &v);
465 if (rval)
466 goto out_free;
467 if (v) {
468 rval = xfs_dir2_block_removename(args);
469 goto out_free;
470 }
471
472 rval = xfs_dir2_isleaf(args, &v);
473 if (rval)
474 goto out_free;
475 if (v)
476 rval = xfs_dir2_leaf_removename(args);
477 else
478 rval = xfs_dir2_node_removename(args);
479out_free:
480 kmem_free(args);
481 return rval;
482}
483
484/*
485 * Replace the inode number of a directory entry.
486 */
487int
488xfs_dir_replace(
489 struct xfs_trans *tp,
490 struct xfs_inode *dp,
491 const struct xfs_name *name, /* name of entry to replace */
492 xfs_ino_t inum, /* new inode number */
493 xfs_extlen_t total) /* bmap's total block count */
494{
495 struct xfs_da_args *args;
496 int rval;
497 bool v;
498
499 ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
500
501 rval = xfs_dir_ino_validate(tp->t_mountp, inum);
502 if (rval)
503 return rval;
504
505 args = kmem_zalloc(sizeof(*args), KM_NOFS);
506 if (!args)
507 return -ENOMEM;
508
509 args->geo = dp->i_mount->m_dir_geo;
510 args->name = name->name;
511 args->namelen = name->len;
512 args->filetype = name->type;
513 args->hashval = xfs_dir2_hashname(dp->i_mount, name);
514 args->inumber = inum;
515 args->dp = dp;
516 args->total = total;
517 args->whichfork = XFS_DATA_FORK;
518 args->trans = tp;
519
520 if (dp->i_df.if_format == XFS_DINODE_FMT_LOCAL) {
521 rval = xfs_dir2_sf_replace(args);
522 goto out_free;
523 }
524
525 rval = xfs_dir2_isblock(args, &v);
526 if (rval)
527 goto out_free;
528 if (v) {
529 rval = xfs_dir2_block_replace(args);
530 goto out_free;
531 }
532
533 rval = xfs_dir2_isleaf(args, &v);
534 if (rval)
535 goto out_free;
536 if (v)
537 rval = xfs_dir2_leaf_replace(args);
538 else
539 rval = xfs_dir2_node_replace(args);
540out_free:
541 kmem_free(args);
542 return rval;
543}
544
545/*
546 * See if this entry can be added to the directory without allocating space.
547 */
548int
549xfs_dir_canenter(
550 xfs_trans_t *tp,
551 xfs_inode_t *dp,
552 struct xfs_name *name) /* name of entry to add */
553{
554 return xfs_dir_createname(tp, dp, name, 0, 0);
555}
556
557/*
558 * Utility routines.
559 */
560
561/*
562 * Add a block to the directory.
563 *
564 * This routine is for data and free blocks, not leaf/node blocks which are
565 * handled by xfs_da_grow_inode.
566 */
567int
568xfs_dir2_grow_inode(
569 struct xfs_da_args *args,
570 int space, /* v2 dir's space XFS_DIR2_xxx_SPACE */
571 xfs_dir2_db_t *dbp) /* out: block number added */
572{
573 struct xfs_inode *dp = args->dp;
574 struct xfs_mount *mp = dp->i_mount;
575 xfs_fileoff_t bno; /* directory offset of new block */
576 int count; /* count of filesystem blocks */
577 int error;
578
579 trace_xfs_dir2_grow_inode(args, space);
580
581 /*
582 * Set lowest possible block in the space requested.
583 */
584 bno = XFS_B_TO_FSBT(mp, space * XFS_DIR2_SPACE_SIZE);
585 count = args->geo->fsbcount;
586
587 error = xfs_da_grow_inode_int(args, &bno, count);
588 if (error)
589 return error;
590
591 *dbp = xfs_dir2_da_to_db(args->geo, (xfs_dablk_t)bno);
592
593 /*
594 * Update file's size if this is the data space and it grew.
595 */
596 if (space == XFS_DIR2_DATA_SPACE) {
597 xfs_fsize_t size; /* directory file (data) size */
598
599 size = XFS_FSB_TO_B(mp, bno + count);
600 if (size > dp->i_disk_size) {
601 dp->i_disk_size = size;
602 xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE);
603 }
604 }
605 return 0;
606}
607
608/*
609 * See if the directory is a single-block form directory.
610 */
611int
612xfs_dir2_isblock(
613 struct xfs_da_args *args,
614 bool *isblock)
615{
616 struct xfs_mount *mp = args->dp->i_mount;
617 xfs_fileoff_t eof;
618 int error;
619
620 error = xfs_bmap_last_offset(args->dp, &eof, XFS_DATA_FORK);
621 if (error)
622 return error;
623
624 *isblock = false;
625 if (XFS_FSB_TO_B(mp, eof) != args->geo->blksize)
626 return 0;
627
628 *isblock = true;
629 if (XFS_IS_CORRUPT(mp, args->dp->i_disk_size != args->geo->blksize))
630 return -EFSCORRUPTED;
631 return 0;
632}
633
634/*
635 * See if the directory is a single-leaf form directory.
636 */
637int
638xfs_dir2_isleaf(
639 struct xfs_da_args *args,
640 bool *isleaf)
641{
642 xfs_fileoff_t eof;
643 int error;
644
645 error = xfs_bmap_last_offset(args->dp, &eof, XFS_DATA_FORK);
646 if (error)
647 return error;
648
649 *isleaf = false;
650 if (eof != args->geo->leafblk + args->geo->fsbcount)
651 return 0;
652
653 *isleaf = true;
654 return 0;
655}
656
657/*
658 * Remove the given block from the directory.
659 * This routine is used for data and free blocks, leaf/node are done
660 * by xfs_da_shrink_inode.
661 */
662int
663xfs_dir2_shrink_inode(
664 struct xfs_da_args *args,
665 xfs_dir2_db_t db,
666 struct xfs_buf *bp)
667{
668 xfs_fileoff_t bno; /* directory file offset */
669 xfs_dablk_t da; /* directory file offset */
670 int done; /* bunmap is finished */
671 struct xfs_inode *dp;
672 int error;
673 struct xfs_mount *mp;
674 struct xfs_trans *tp;
675
676 trace_xfs_dir2_shrink_inode(args, db);
677
678 dp = args->dp;
679 mp = dp->i_mount;
680 tp = args->trans;
681 da = xfs_dir2_db_to_da(args->geo, db);
682
683 /* Unmap the fsblock(s). */
684 error = xfs_bunmapi(tp, dp, da, args->geo->fsbcount, 0, 0, &done);
685 if (error) {
686 /*
687 * ENOSPC actually can happen if we're in a removename with no
688 * space reservation, and the resulting block removal would
689 * cause a bmap btree split or conversion from extents to btree.
690 * This can only happen for un-fragmented directory blocks,
691 * since you need to be punching out the middle of an extent.
692 * In this case we need to leave the block in the file, and not
693 * binval it. So the block has to be in a consistent empty
694 * state and appropriately logged. We don't free up the buffer,
695 * the caller can tell it hasn't happened since it got an error
696 * back.
697 */
698 return error;
699 }
700 ASSERT(done);
701 /*
702 * Invalidate the buffer from the transaction.
703 */
704 xfs_trans_binval(tp, bp);
705 /*
706 * If it's not a data block, we're done.
707 */
708 if (db >= xfs_dir2_byte_to_db(args->geo, XFS_DIR2_LEAF_OFFSET))
709 return 0;
710 /*
711 * If the block isn't the last one in the directory, we're done.
712 */
713 if (dp->i_disk_size > xfs_dir2_db_off_to_byte(args->geo, db + 1, 0))
714 return 0;
715 bno = da;
716 if ((error = xfs_bmap_last_before(tp, dp, &bno, XFS_DATA_FORK))) {
717 /*
718 * This can't really happen unless there's kernel corruption.
719 */
720 return error;
721 }
722 if (db == args->geo->datablk)
723 ASSERT(bno == 0);
724 else
725 ASSERT(bno > 0);
726 /*
727 * Set the size to the new last block.
728 */
729 dp->i_disk_size = XFS_FSB_TO_B(mp, bno);
730 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
731 return 0;
732}
733
734/* Returns true if the directory entry name is valid. */
735bool
736xfs_dir2_namecheck(
737 const void *name,
738 size_t length)
739{
740 /*
741 * MAXNAMELEN includes the trailing null, but (name/length) leave it
742 * out, so use >= for the length check.
743 */
744 if (length >= MAXNAMELEN)
745 return false;
746
747 /* There shouldn't be any slashes or nulls here */
748 return !memchr(name, '/', length) && !memchr(name, 0, length);
749}
750
751xfs_dahash_t
752xfs_dir2_hashname(
753 struct xfs_mount *mp,
754 const struct xfs_name *name)
755{
756 if (unlikely(xfs_has_asciici(mp)))
757 return xfs_ascii_ci_hashname(name);
758 return xfs_da_hashname(name->name, name->len);
759}
760
761enum xfs_dacmp
762xfs_dir2_compname(
763 struct xfs_da_args *args,
764 const unsigned char *name,
765 int len)
766{
767 if (unlikely(xfs_has_asciici(args->dp->i_mount)))
768 return xfs_ascii_ci_compname(args, name, len);
769 return xfs_da_compname(args, name, len);
770}
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_mount.h"
24#include "xfs_da_format.h"
25#include "xfs_da_btree.h"
26#include "xfs_inode.h"
27#include "xfs_trans.h"
28#include "xfs_inode_item.h"
29#include "xfs_bmap.h"
30#include "xfs_dir2.h"
31#include "xfs_dir2_priv.h"
32#include "xfs_error.h"
33#include "xfs_trace.h"
34
35struct xfs_name xfs_name_dotdot = { (unsigned char *)"..", 2, XFS_DIR3_FT_DIR };
36
37/*
38 * @mode, if set, indicates that the type field needs to be set up.
39 * This uses the transformation from file mode to DT_* as defined in linux/fs.h
40 * for file type specification. This will be propagated into the directory
41 * structure if appropriate for the given operation and filesystem config.
42 */
43const unsigned char xfs_mode_to_ftype[S_IFMT >> S_SHIFT] = {
44 [0] = XFS_DIR3_FT_UNKNOWN,
45 [S_IFREG >> S_SHIFT] = XFS_DIR3_FT_REG_FILE,
46 [S_IFDIR >> S_SHIFT] = XFS_DIR3_FT_DIR,
47 [S_IFCHR >> S_SHIFT] = XFS_DIR3_FT_CHRDEV,
48 [S_IFBLK >> S_SHIFT] = XFS_DIR3_FT_BLKDEV,
49 [S_IFIFO >> S_SHIFT] = XFS_DIR3_FT_FIFO,
50 [S_IFSOCK >> S_SHIFT] = XFS_DIR3_FT_SOCK,
51 [S_IFLNK >> S_SHIFT] = XFS_DIR3_FT_SYMLINK,
52};
53
54/*
55 * ASCII case-insensitive (ie. A-Z) support for directories that was
56 * used in IRIX.
57 */
58STATIC xfs_dahash_t
59xfs_ascii_ci_hashname(
60 struct xfs_name *name)
61{
62 xfs_dahash_t hash;
63 int i;
64
65 for (i = 0, hash = 0; i < name->len; i++)
66 hash = tolower(name->name[i]) ^ rol32(hash, 7);
67
68 return hash;
69}
70
71STATIC enum xfs_dacmp
72xfs_ascii_ci_compname(
73 struct xfs_da_args *args,
74 const unsigned char *name,
75 int len)
76{
77 enum xfs_dacmp result;
78 int i;
79
80 if (args->namelen != len)
81 return XFS_CMP_DIFFERENT;
82
83 result = XFS_CMP_EXACT;
84 for (i = 0; i < len; i++) {
85 if (args->name[i] == name[i])
86 continue;
87 if (tolower(args->name[i]) != tolower(name[i]))
88 return XFS_CMP_DIFFERENT;
89 result = XFS_CMP_CASE;
90 }
91
92 return result;
93}
94
95static struct xfs_nameops xfs_ascii_ci_nameops = {
96 .hashname = xfs_ascii_ci_hashname,
97 .compname = xfs_ascii_ci_compname,
98};
99
100int
101xfs_da_mount(
102 struct xfs_mount *mp)
103{
104 struct xfs_da_geometry *dageo;
105 int nodehdr_size;
106
107
108 ASSERT(mp->m_sb.sb_versionnum & XFS_SB_VERSION_DIRV2BIT);
109 ASSERT((1 << (mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog)) <=
110 XFS_MAX_BLOCKSIZE);
111
112 mp->m_dir_inode_ops = xfs_dir_get_ops(mp, NULL);
113 mp->m_nondir_inode_ops = xfs_nondir_get_ops(mp, NULL);
114
115 nodehdr_size = mp->m_dir_inode_ops->node_hdr_size;
116 mp->m_dir_geo = kmem_zalloc(sizeof(struct xfs_da_geometry),
117 KM_SLEEP | KM_MAYFAIL);
118 mp->m_attr_geo = kmem_zalloc(sizeof(struct xfs_da_geometry),
119 KM_SLEEP | KM_MAYFAIL);
120 if (!mp->m_dir_geo || !mp->m_attr_geo) {
121 kmem_free(mp->m_dir_geo);
122 kmem_free(mp->m_attr_geo);
123 return -ENOMEM;
124 }
125
126 /* set up directory geometry */
127 dageo = mp->m_dir_geo;
128 dageo->blklog = mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog;
129 dageo->fsblog = mp->m_sb.sb_blocklog;
130 dageo->blksize = 1 << dageo->blklog;
131 dageo->fsbcount = 1 << mp->m_sb.sb_dirblklog;
132
133 /*
134 * Now we've set up the block conversion variables, we can calculate the
135 * segment block constants using the geometry structure.
136 */
137 dageo->datablk = xfs_dir2_byte_to_da(dageo, XFS_DIR2_DATA_OFFSET);
138 dageo->leafblk = xfs_dir2_byte_to_da(dageo, XFS_DIR2_LEAF_OFFSET);
139 dageo->freeblk = xfs_dir2_byte_to_da(dageo, XFS_DIR2_FREE_OFFSET);
140 dageo->node_ents = (dageo->blksize - nodehdr_size) /
141 (uint)sizeof(xfs_da_node_entry_t);
142 dageo->magicpct = (dageo->blksize * 37) / 100;
143
144 /* set up attribute geometry - single fsb only */
145 dageo = mp->m_attr_geo;
146 dageo->blklog = mp->m_sb.sb_blocklog;
147 dageo->fsblog = mp->m_sb.sb_blocklog;
148 dageo->blksize = 1 << dageo->blklog;
149 dageo->fsbcount = 1;
150 dageo->node_ents = (dageo->blksize - nodehdr_size) /
151 (uint)sizeof(xfs_da_node_entry_t);
152 dageo->magicpct = (dageo->blksize * 37) / 100;
153
154 if (xfs_sb_version_hasasciici(&mp->m_sb))
155 mp->m_dirnameops = &xfs_ascii_ci_nameops;
156 else
157 mp->m_dirnameops = &xfs_default_nameops;
158
159 return 0;
160}
161
162void
163xfs_da_unmount(
164 struct xfs_mount *mp)
165{
166 kmem_free(mp->m_dir_geo);
167 kmem_free(mp->m_attr_geo);
168}
169
170/*
171 * Return 1 if directory contains only "." and "..".
172 */
173int
174xfs_dir_isempty(
175 xfs_inode_t *dp)
176{
177 xfs_dir2_sf_hdr_t *sfp;
178
179 ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
180 if (dp->i_d.di_size == 0) /* might happen during shutdown. */
181 return 1;
182 if (dp->i_d.di_size > XFS_IFORK_DSIZE(dp))
183 return 0;
184 sfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
185 return !sfp->count;
186}
187
188/*
189 * Validate a given inode number.
190 */
191int
192xfs_dir_ino_validate(
193 xfs_mount_t *mp,
194 xfs_ino_t ino)
195{
196 xfs_agblock_t agblkno;
197 xfs_agino_t agino;
198 xfs_agnumber_t agno;
199 int ino_ok;
200 int ioff;
201
202 agno = XFS_INO_TO_AGNO(mp, ino);
203 agblkno = XFS_INO_TO_AGBNO(mp, ino);
204 ioff = XFS_INO_TO_OFFSET(mp, ino);
205 agino = XFS_OFFBNO_TO_AGINO(mp, agblkno, ioff);
206 ino_ok =
207 agno < mp->m_sb.sb_agcount &&
208 agblkno < mp->m_sb.sb_agblocks &&
209 agblkno != 0 &&
210 ioff < (1 << mp->m_sb.sb_inopblog) &&
211 XFS_AGINO_TO_INO(mp, agno, agino) == ino;
212 if (unlikely(XFS_TEST_ERROR(!ino_ok, mp, XFS_ERRTAG_DIR_INO_VALIDATE,
213 XFS_RANDOM_DIR_INO_VALIDATE))) {
214 xfs_warn(mp, "Invalid inode number 0x%Lx",
215 (unsigned long long) ino);
216 XFS_ERROR_REPORT("xfs_dir_ino_validate", XFS_ERRLEVEL_LOW, mp);
217 return -EFSCORRUPTED;
218 }
219 return 0;
220}
221
222/*
223 * Initialize a directory with its "." and ".." entries.
224 */
225int
226xfs_dir_init(
227 xfs_trans_t *tp,
228 xfs_inode_t *dp,
229 xfs_inode_t *pdp)
230{
231 struct xfs_da_args *args;
232 int error;
233
234 ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
235 error = xfs_dir_ino_validate(tp->t_mountp, pdp->i_ino);
236 if (error)
237 return error;
238
239 args = kmem_zalloc(sizeof(*args), KM_SLEEP | KM_NOFS);
240 if (!args)
241 return -ENOMEM;
242
243 args->geo = dp->i_mount->m_dir_geo;
244 args->dp = dp;
245 args->trans = tp;
246 error = xfs_dir2_sf_create(args, pdp->i_ino);
247 kmem_free(args);
248 return error;
249}
250
251/*
252 * Enter a name in a directory, or check for available space.
253 * If inum is 0, only the available space test is performed.
254 */
255int
256xfs_dir_createname(
257 xfs_trans_t *tp,
258 xfs_inode_t *dp,
259 struct xfs_name *name,
260 xfs_ino_t inum, /* new entry inode number */
261 xfs_fsblock_t *first, /* bmap's firstblock */
262 xfs_bmap_free_t *flist, /* bmap's freeblock list */
263 xfs_extlen_t total) /* bmap's total block count */
264{
265 struct xfs_da_args *args;
266 int rval;
267 int v; /* type-checking value */
268
269 ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
270 if (inum) {
271 rval = xfs_dir_ino_validate(tp->t_mountp, inum);
272 if (rval)
273 return rval;
274 XFS_STATS_INC(dp->i_mount, xs_dir_create);
275 }
276
277 args = kmem_zalloc(sizeof(*args), KM_SLEEP | KM_NOFS);
278 if (!args)
279 return -ENOMEM;
280
281 args->geo = dp->i_mount->m_dir_geo;
282 args->name = name->name;
283 args->namelen = name->len;
284 args->filetype = name->type;
285 args->hashval = dp->i_mount->m_dirnameops->hashname(name);
286 args->inumber = inum;
287 args->dp = dp;
288 args->firstblock = first;
289 args->flist = flist;
290 args->total = total;
291 args->whichfork = XFS_DATA_FORK;
292 args->trans = tp;
293 args->op_flags = XFS_DA_OP_ADDNAME | XFS_DA_OP_OKNOENT;
294 if (!inum)
295 args->op_flags |= XFS_DA_OP_JUSTCHECK;
296
297 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL) {
298 rval = xfs_dir2_sf_addname(args);
299 goto out_free;
300 }
301
302 rval = xfs_dir2_isblock(args, &v);
303 if (rval)
304 goto out_free;
305 if (v) {
306 rval = xfs_dir2_block_addname(args);
307 goto out_free;
308 }
309
310 rval = xfs_dir2_isleaf(args, &v);
311 if (rval)
312 goto out_free;
313 if (v)
314 rval = xfs_dir2_leaf_addname(args);
315 else
316 rval = xfs_dir2_node_addname(args);
317
318out_free:
319 kmem_free(args);
320 return rval;
321}
322
323/*
324 * If doing a CI lookup and case-insensitive match, dup actual name into
325 * args.value. Return EEXIST for success (ie. name found) or an error.
326 */
327int
328xfs_dir_cilookup_result(
329 struct xfs_da_args *args,
330 const unsigned char *name,
331 int len)
332{
333 if (args->cmpresult == XFS_CMP_DIFFERENT)
334 return -ENOENT;
335 if (args->cmpresult != XFS_CMP_CASE ||
336 !(args->op_flags & XFS_DA_OP_CILOOKUP))
337 return -EEXIST;
338
339 args->value = kmem_alloc(len, KM_NOFS | KM_MAYFAIL);
340 if (!args->value)
341 return -ENOMEM;
342
343 memcpy(args->value, name, len);
344 args->valuelen = len;
345 return -EEXIST;
346}
347
348/*
349 * Lookup a name in a directory, give back the inode number.
350 * If ci_name is not NULL, returns the actual name in ci_name if it differs
351 * to name, or ci_name->name is set to NULL for an exact match.
352 */
353
354int
355xfs_dir_lookup(
356 xfs_trans_t *tp,
357 xfs_inode_t *dp,
358 struct xfs_name *name,
359 xfs_ino_t *inum, /* out: inode number */
360 struct xfs_name *ci_name) /* out: actual name if CI match */
361{
362 struct xfs_da_args *args;
363 int rval;
364 int v; /* type-checking value */
365 int lock_mode;
366
367 ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
368 XFS_STATS_INC(dp->i_mount, xs_dir_lookup);
369
370 /*
371 * We need to use KM_NOFS here so that lockdep will not throw false
372 * positive deadlock warnings on a non-transactional lookup path. It is
373 * safe to recurse into inode recalim in that case, but lockdep can't
374 * easily be taught about it. Hence KM_NOFS avoids having to add more
375 * lockdep Doing this avoids having to add a bunch of lockdep class
376 * annotations into the reclaim path for the ilock.
377 */
378 args = kmem_zalloc(sizeof(*args), KM_SLEEP | KM_NOFS);
379 args->geo = dp->i_mount->m_dir_geo;
380 args->name = name->name;
381 args->namelen = name->len;
382 args->filetype = name->type;
383 args->hashval = dp->i_mount->m_dirnameops->hashname(name);
384 args->dp = dp;
385 args->whichfork = XFS_DATA_FORK;
386 args->trans = tp;
387 args->op_flags = XFS_DA_OP_OKNOENT;
388 if (ci_name)
389 args->op_flags |= XFS_DA_OP_CILOOKUP;
390
391 lock_mode = xfs_ilock_data_map_shared(dp);
392 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL) {
393 rval = xfs_dir2_sf_lookup(args);
394 goto out_check_rval;
395 }
396
397 rval = xfs_dir2_isblock(args, &v);
398 if (rval)
399 goto out_free;
400 if (v) {
401 rval = xfs_dir2_block_lookup(args);
402 goto out_check_rval;
403 }
404
405 rval = xfs_dir2_isleaf(args, &v);
406 if (rval)
407 goto out_free;
408 if (v)
409 rval = xfs_dir2_leaf_lookup(args);
410 else
411 rval = xfs_dir2_node_lookup(args);
412
413out_check_rval:
414 if (rval == -EEXIST)
415 rval = 0;
416 if (!rval) {
417 *inum = args->inumber;
418 if (ci_name) {
419 ci_name->name = args->value;
420 ci_name->len = args->valuelen;
421 }
422 }
423out_free:
424 xfs_iunlock(dp, lock_mode);
425 kmem_free(args);
426 return rval;
427}
428
429/*
430 * Remove an entry from a directory.
431 */
432int
433xfs_dir_removename(
434 xfs_trans_t *tp,
435 xfs_inode_t *dp,
436 struct xfs_name *name,
437 xfs_ino_t ino,
438 xfs_fsblock_t *first, /* bmap's firstblock */
439 xfs_bmap_free_t *flist, /* bmap's freeblock list */
440 xfs_extlen_t total) /* bmap's total block count */
441{
442 struct xfs_da_args *args;
443 int rval;
444 int v; /* type-checking value */
445
446 ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
447 XFS_STATS_INC(dp->i_mount, xs_dir_remove);
448
449 args = kmem_zalloc(sizeof(*args), KM_SLEEP | KM_NOFS);
450 if (!args)
451 return -ENOMEM;
452
453 args->geo = dp->i_mount->m_dir_geo;
454 args->name = name->name;
455 args->namelen = name->len;
456 args->filetype = name->type;
457 args->hashval = dp->i_mount->m_dirnameops->hashname(name);
458 args->inumber = ino;
459 args->dp = dp;
460 args->firstblock = first;
461 args->flist = flist;
462 args->total = total;
463 args->whichfork = XFS_DATA_FORK;
464 args->trans = tp;
465
466 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL) {
467 rval = xfs_dir2_sf_removename(args);
468 goto out_free;
469 }
470
471 rval = xfs_dir2_isblock(args, &v);
472 if (rval)
473 goto out_free;
474 if (v) {
475 rval = xfs_dir2_block_removename(args);
476 goto out_free;
477 }
478
479 rval = xfs_dir2_isleaf(args, &v);
480 if (rval)
481 goto out_free;
482 if (v)
483 rval = xfs_dir2_leaf_removename(args);
484 else
485 rval = xfs_dir2_node_removename(args);
486out_free:
487 kmem_free(args);
488 return rval;
489}
490
491/*
492 * Replace the inode number of a directory entry.
493 */
494int
495xfs_dir_replace(
496 xfs_trans_t *tp,
497 xfs_inode_t *dp,
498 struct xfs_name *name, /* name of entry to replace */
499 xfs_ino_t inum, /* new inode number */
500 xfs_fsblock_t *first, /* bmap's firstblock */
501 xfs_bmap_free_t *flist, /* bmap's freeblock list */
502 xfs_extlen_t total) /* bmap's total block count */
503{
504 struct xfs_da_args *args;
505 int rval;
506 int v; /* type-checking value */
507
508 ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
509
510 rval = xfs_dir_ino_validate(tp->t_mountp, inum);
511 if (rval)
512 return rval;
513
514 args = kmem_zalloc(sizeof(*args), KM_SLEEP | KM_NOFS);
515 if (!args)
516 return -ENOMEM;
517
518 args->geo = dp->i_mount->m_dir_geo;
519 args->name = name->name;
520 args->namelen = name->len;
521 args->filetype = name->type;
522 args->hashval = dp->i_mount->m_dirnameops->hashname(name);
523 args->inumber = inum;
524 args->dp = dp;
525 args->firstblock = first;
526 args->flist = flist;
527 args->total = total;
528 args->whichfork = XFS_DATA_FORK;
529 args->trans = tp;
530
531 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL) {
532 rval = xfs_dir2_sf_replace(args);
533 goto out_free;
534 }
535
536 rval = xfs_dir2_isblock(args, &v);
537 if (rval)
538 goto out_free;
539 if (v) {
540 rval = xfs_dir2_block_replace(args);
541 goto out_free;
542 }
543
544 rval = xfs_dir2_isleaf(args, &v);
545 if (rval)
546 goto out_free;
547 if (v)
548 rval = xfs_dir2_leaf_replace(args);
549 else
550 rval = xfs_dir2_node_replace(args);
551out_free:
552 kmem_free(args);
553 return rval;
554}
555
556/*
557 * See if this entry can be added to the directory without allocating space.
558 */
559int
560xfs_dir_canenter(
561 xfs_trans_t *tp,
562 xfs_inode_t *dp,
563 struct xfs_name *name) /* name of entry to add */
564{
565 return xfs_dir_createname(tp, dp, name, 0, NULL, NULL, 0);
566}
567
568/*
569 * Utility routines.
570 */
571
572/*
573 * Add a block to the directory.
574 *
575 * This routine is for data and free blocks, not leaf/node blocks which are
576 * handled by xfs_da_grow_inode.
577 */
578int
579xfs_dir2_grow_inode(
580 struct xfs_da_args *args,
581 int space, /* v2 dir's space XFS_DIR2_xxx_SPACE */
582 xfs_dir2_db_t *dbp) /* out: block number added */
583{
584 struct xfs_inode *dp = args->dp;
585 struct xfs_mount *mp = dp->i_mount;
586 xfs_fileoff_t bno; /* directory offset of new block */
587 int count; /* count of filesystem blocks */
588 int error;
589
590 trace_xfs_dir2_grow_inode(args, space);
591
592 /*
593 * Set lowest possible block in the space requested.
594 */
595 bno = XFS_B_TO_FSBT(mp, space * XFS_DIR2_SPACE_SIZE);
596 count = args->geo->fsbcount;
597
598 error = xfs_da_grow_inode_int(args, &bno, count);
599 if (error)
600 return error;
601
602 *dbp = xfs_dir2_da_to_db(args->geo, (xfs_dablk_t)bno);
603
604 /*
605 * Update file's size if this is the data space and it grew.
606 */
607 if (space == XFS_DIR2_DATA_SPACE) {
608 xfs_fsize_t size; /* directory file (data) size */
609
610 size = XFS_FSB_TO_B(mp, bno + count);
611 if (size > dp->i_d.di_size) {
612 dp->i_d.di_size = size;
613 xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE);
614 }
615 }
616 return 0;
617}
618
619/*
620 * See if the directory is a single-block form directory.
621 */
622int
623xfs_dir2_isblock(
624 struct xfs_da_args *args,
625 int *vp) /* out: 1 is block, 0 is not block */
626{
627 xfs_fileoff_t last; /* last file offset */
628 int rval;
629
630 if ((rval = xfs_bmap_last_offset(args->dp, &last, XFS_DATA_FORK)))
631 return rval;
632 rval = XFS_FSB_TO_B(args->dp->i_mount, last) == args->geo->blksize;
633 ASSERT(rval == 0 || args->dp->i_d.di_size == args->geo->blksize);
634 *vp = rval;
635 return 0;
636}
637
638/*
639 * See if the directory is a single-leaf form directory.
640 */
641int
642xfs_dir2_isleaf(
643 struct xfs_da_args *args,
644 int *vp) /* out: 1 is block, 0 is not block */
645{
646 xfs_fileoff_t last; /* last file offset */
647 int rval;
648
649 if ((rval = xfs_bmap_last_offset(args->dp, &last, XFS_DATA_FORK)))
650 return rval;
651 *vp = last == args->geo->leafblk + args->geo->fsbcount;
652 return 0;
653}
654
655/*
656 * Remove the given block from the directory.
657 * This routine is used for data and free blocks, leaf/node are done
658 * by xfs_da_shrink_inode.
659 */
660int
661xfs_dir2_shrink_inode(
662 xfs_da_args_t *args,
663 xfs_dir2_db_t db,
664 struct xfs_buf *bp)
665{
666 xfs_fileoff_t bno; /* directory file offset */
667 xfs_dablk_t da; /* directory file offset */
668 int done; /* bunmap is finished */
669 xfs_inode_t *dp;
670 int error;
671 xfs_mount_t *mp;
672 xfs_trans_t *tp;
673
674 trace_xfs_dir2_shrink_inode(args, db);
675
676 dp = args->dp;
677 mp = dp->i_mount;
678 tp = args->trans;
679 da = xfs_dir2_db_to_da(args->geo, db);
680
681 /* Unmap the fsblock(s). */
682 error = xfs_bunmapi(tp, dp, da, args->geo->fsbcount, 0, 0,
683 args->firstblock, args->flist, &done);
684 if (error) {
685 /*
686 * ENOSPC actually can happen if we're in a removename with no
687 * space reservation, and the resulting block removal would
688 * cause a bmap btree split or conversion from extents to btree.
689 * This can only happen for un-fragmented directory blocks,
690 * since you need to be punching out the middle of an extent.
691 * In this case we need to leave the block in the file, and not
692 * binval it. So the block has to be in a consistent empty
693 * state and appropriately logged. We don't free up the buffer,
694 * the caller can tell it hasn't happened since it got an error
695 * back.
696 */
697 return error;
698 }
699 ASSERT(done);
700 /*
701 * Invalidate the buffer from the transaction.
702 */
703 xfs_trans_binval(tp, bp);
704 /*
705 * If it's not a data block, we're done.
706 */
707 if (db >= xfs_dir2_byte_to_db(args->geo, XFS_DIR2_LEAF_OFFSET))
708 return 0;
709 /*
710 * If the block isn't the last one in the directory, we're done.
711 */
712 if (dp->i_d.di_size > xfs_dir2_db_off_to_byte(args->geo, db + 1, 0))
713 return 0;
714 bno = da;
715 if ((error = xfs_bmap_last_before(tp, dp, &bno, XFS_DATA_FORK))) {
716 /*
717 * This can't really happen unless there's kernel corruption.
718 */
719 return error;
720 }
721 if (db == args->geo->datablk)
722 ASSERT(bno == 0);
723 else
724 ASSERT(bno > 0);
725 /*
726 * Set the size to the new last block.
727 */
728 dp->i_d.di_size = XFS_FSB_TO_B(mp, bno);
729 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
730 return 0;
731}