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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 = tolower(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 (tolower(args->name[i]) != tolower(name[i]))
89 return XFS_CMP_DIFFERENT;
90 result = XFS_CMP_CASE;
91 }
92
93 return result;
94}
95
96int
97xfs_da_mount(
98 struct xfs_mount *mp)
99{
100 struct xfs_da_geometry *dageo;
101
102
103 ASSERT(mp->m_sb.sb_versionnum & XFS_SB_VERSION_DIRV2BIT);
104 ASSERT(xfs_dir2_dirblock_bytes(&mp->m_sb) <= XFS_MAX_BLOCKSIZE);
105
106 mp->m_dir_geo = kmem_zalloc(sizeof(struct xfs_da_geometry),
107 KM_MAYFAIL);
108 mp->m_attr_geo = kmem_zalloc(sizeof(struct xfs_da_geometry),
109 KM_MAYFAIL);
110 if (!mp->m_dir_geo || !mp->m_attr_geo) {
111 kmem_free(mp->m_dir_geo);
112 kmem_free(mp->m_attr_geo);
113 return -ENOMEM;
114 }
115
116 /* set up directory geometry */
117 dageo = mp->m_dir_geo;
118 dageo->blklog = mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog;
119 dageo->fsblog = mp->m_sb.sb_blocklog;
120 dageo->blksize = xfs_dir2_dirblock_bytes(&mp->m_sb);
121 dageo->fsbcount = 1 << mp->m_sb.sb_dirblklog;
122 if (xfs_has_crc(mp)) {
123 dageo->node_hdr_size = sizeof(struct xfs_da3_node_hdr);
124 dageo->leaf_hdr_size = sizeof(struct xfs_dir3_leaf_hdr);
125 dageo->free_hdr_size = sizeof(struct xfs_dir3_free_hdr);
126 dageo->data_entry_offset =
127 sizeof(struct xfs_dir3_data_hdr);
128 } else {
129 dageo->node_hdr_size = sizeof(struct xfs_da_node_hdr);
130 dageo->leaf_hdr_size = sizeof(struct xfs_dir2_leaf_hdr);
131 dageo->free_hdr_size = sizeof(struct xfs_dir2_free_hdr);
132 dageo->data_entry_offset =
133 sizeof(struct xfs_dir2_data_hdr);
134 }
135 dageo->leaf_max_ents = (dageo->blksize - dageo->leaf_hdr_size) /
136 sizeof(struct xfs_dir2_leaf_entry);
137 dageo->free_max_bests = (dageo->blksize - dageo->free_hdr_size) /
138 sizeof(xfs_dir2_data_off_t);
139
140 dageo->data_first_offset = dageo->data_entry_offset +
141 xfs_dir2_data_entsize(mp, 1) +
142 xfs_dir2_data_entsize(mp, 2);
143
144 /*
145 * Now we've set up the block conversion variables, we can calculate the
146 * segment block constants using the geometry structure.
147 */
148 dageo->datablk = xfs_dir2_byte_to_da(dageo, XFS_DIR2_DATA_OFFSET);
149 dageo->leafblk = xfs_dir2_byte_to_da(dageo, XFS_DIR2_LEAF_OFFSET);
150 dageo->freeblk = xfs_dir2_byte_to_da(dageo, XFS_DIR2_FREE_OFFSET);
151 dageo->node_ents = (dageo->blksize - dageo->node_hdr_size) /
152 (uint)sizeof(xfs_da_node_entry_t);
153 dageo->max_extents = (XFS_DIR2_MAX_SPACES * XFS_DIR2_SPACE_SIZE) >>
154 mp->m_sb.sb_blocklog;
155 dageo->magicpct = (dageo->blksize * 37) / 100;
156
157 /* set up attribute geometry - single fsb only */
158 dageo = mp->m_attr_geo;
159 dageo->blklog = mp->m_sb.sb_blocklog;
160 dageo->fsblog = mp->m_sb.sb_blocklog;
161 dageo->blksize = 1 << dageo->blklog;
162 dageo->fsbcount = 1;
163 dageo->node_hdr_size = mp->m_dir_geo->node_hdr_size;
164 dageo->node_ents = (dageo->blksize - dageo->node_hdr_size) /
165 (uint)sizeof(xfs_da_node_entry_t);
166
167 if (xfs_has_large_extent_counts(mp))
168 dageo->max_extents = XFS_MAX_EXTCNT_ATTR_FORK_LARGE;
169 else
170 dageo->max_extents = XFS_MAX_EXTCNT_ATTR_FORK_SMALL;
171
172 dageo->magicpct = (dageo->blksize * 37) / 100;
173 return 0;
174}
175
176void
177xfs_da_unmount(
178 struct xfs_mount *mp)
179{
180 kmem_free(mp->m_dir_geo);
181 kmem_free(mp->m_attr_geo);
182}
183
184/*
185 * Return 1 if directory contains only "." and "..".
186 */
187int
188xfs_dir_isempty(
189 xfs_inode_t *dp)
190{
191 xfs_dir2_sf_hdr_t *sfp;
192
193 ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
194 if (dp->i_disk_size == 0) /* might happen during shutdown. */
195 return 1;
196 if (dp->i_disk_size > xfs_inode_data_fork_size(dp))
197 return 0;
198 sfp = (xfs_dir2_sf_hdr_t *)dp->i_df.if_u1.if_data;
199 return !sfp->count;
200}
201
202/*
203 * Validate a given inode number.
204 */
205int
206xfs_dir_ino_validate(
207 xfs_mount_t *mp,
208 xfs_ino_t ino)
209{
210 bool ino_ok = xfs_verify_dir_ino(mp, ino);
211
212 if (XFS_IS_CORRUPT(mp, !ino_ok) ||
213 XFS_TEST_ERROR(false, mp, XFS_ERRTAG_DIR_INO_VALIDATE)) {
214 xfs_warn(mp, "Invalid inode number 0x%Lx",
215 (unsigned long long) ino);
216 return -EFSCORRUPTED;
217 }
218 return 0;
219}
220
221/*
222 * Initialize a directory with its "." and ".." entries.
223 */
224int
225xfs_dir_init(
226 xfs_trans_t *tp,
227 xfs_inode_t *dp,
228 xfs_inode_t *pdp)
229{
230 struct xfs_da_args *args;
231 int error;
232
233 ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
234 error = xfs_dir_ino_validate(tp->t_mountp, pdp->i_ino);
235 if (error)
236 return error;
237
238 args = kmem_zalloc(sizeof(*args), KM_NOFS);
239 if (!args)
240 return -ENOMEM;
241
242 args->geo = dp->i_mount->m_dir_geo;
243 args->dp = dp;
244 args->trans = tp;
245 error = xfs_dir2_sf_create(args, pdp->i_ino);
246 kmem_free(args);
247 return error;
248}
249
250/*
251 * Enter a name in a directory, or check for available space.
252 * If inum is 0, only the available space test is performed.
253 */
254int
255xfs_dir_createname(
256 struct xfs_trans *tp,
257 struct xfs_inode *dp,
258 const struct xfs_name *name,
259 xfs_ino_t inum, /* new entry inode number */
260 xfs_extlen_t total) /* bmap's total block count */
261{
262 struct xfs_da_args *args;
263 int rval;
264 bool v;
265
266 ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
267
268 if (inum) {
269 rval = xfs_dir_ino_validate(tp->t_mountp, inum);
270 if (rval)
271 return rval;
272 XFS_STATS_INC(dp->i_mount, xs_dir_create);
273 }
274
275 args = kmem_zalloc(sizeof(*args), KM_NOFS);
276 if (!args)
277 return -ENOMEM;
278
279 args->geo = dp->i_mount->m_dir_geo;
280 args->name = name->name;
281 args->namelen = name->len;
282 args->filetype = name->type;
283 args->hashval = xfs_dir2_hashname(dp->i_mount, name);
284 args->inumber = inum;
285 args->dp = dp;
286 args->total = total;
287 args->whichfork = XFS_DATA_FORK;
288 args->trans = tp;
289 args->op_flags = XFS_DA_OP_ADDNAME | XFS_DA_OP_OKNOENT;
290 if (!inum)
291 args->op_flags |= XFS_DA_OP_JUSTCHECK;
292
293 if (dp->i_df.if_format == XFS_DINODE_FMT_LOCAL) {
294 rval = xfs_dir2_sf_addname(args);
295 goto out_free;
296 }
297
298 rval = xfs_dir2_isblock(args, &v);
299 if (rval)
300 goto out_free;
301 if (v) {
302 rval = xfs_dir2_block_addname(args);
303 goto out_free;
304 }
305
306 rval = xfs_dir2_isleaf(args, &v);
307 if (rval)
308 goto out_free;
309 if (v)
310 rval = xfs_dir2_leaf_addname(args);
311 else
312 rval = xfs_dir2_node_addname(args);
313
314out_free:
315 kmem_free(args);
316 return rval;
317}
318
319/*
320 * If doing a CI lookup and case-insensitive match, dup actual name into
321 * args.value. Return EEXIST for success (ie. name found) or an error.
322 */
323int
324xfs_dir_cilookup_result(
325 struct xfs_da_args *args,
326 const unsigned char *name,
327 int len)
328{
329 if (args->cmpresult == XFS_CMP_DIFFERENT)
330 return -ENOENT;
331 if (args->cmpresult != XFS_CMP_CASE ||
332 !(args->op_flags & XFS_DA_OP_CILOOKUP))
333 return -EEXIST;
334
335 args->value = kmem_alloc(len, KM_NOFS | KM_MAYFAIL);
336 if (!args->value)
337 return -ENOMEM;
338
339 memcpy(args->value, name, len);
340 args->valuelen = len;
341 return -EEXIST;
342}
343
344/*
345 * Lookup a name in a directory, give back the inode number.
346 * If ci_name is not NULL, returns the actual name in ci_name if it differs
347 * to name, or ci_name->name is set to NULL for an exact match.
348 */
349
350int
351xfs_dir_lookup(
352 struct xfs_trans *tp,
353 struct xfs_inode *dp,
354 const struct xfs_name *name,
355 xfs_ino_t *inum, /* out: inode number */
356 struct xfs_name *ci_name) /* out: actual name if CI match */
357{
358 struct xfs_da_args *args;
359 int rval;
360 bool v;
361 int lock_mode;
362
363 ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
364 XFS_STATS_INC(dp->i_mount, xs_dir_lookup);
365
366 /*
367 * We need to use KM_NOFS here so that lockdep will not throw false
368 * positive deadlock warnings on a non-transactional lookup path. It is
369 * safe to recurse into inode recalim in that case, but lockdep can't
370 * easily be taught about it. Hence KM_NOFS avoids having to add more
371 * lockdep Doing this avoids having to add a bunch of lockdep class
372 * annotations into the reclaim path for the ilock.
373 */
374 args = kmem_zalloc(sizeof(*args), KM_NOFS);
375 args->geo = dp->i_mount->m_dir_geo;
376 args->name = name->name;
377 args->namelen = name->len;
378 args->filetype = name->type;
379 args->hashval = xfs_dir2_hashname(dp->i_mount, name);
380 args->dp = dp;
381 args->whichfork = XFS_DATA_FORK;
382 args->trans = tp;
383 args->op_flags = XFS_DA_OP_OKNOENT;
384 if (ci_name)
385 args->op_flags |= XFS_DA_OP_CILOOKUP;
386
387 lock_mode = xfs_ilock_data_map_shared(dp);
388 if (dp->i_df.if_format == XFS_DINODE_FMT_LOCAL) {
389 rval = xfs_dir2_sf_lookup(args);
390 goto out_check_rval;
391 }
392
393 rval = xfs_dir2_isblock(args, &v);
394 if (rval)
395 goto out_free;
396 if (v) {
397 rval = xfs_dir2_block_lookup(args);
398 goto out_check_rval;
399 }
400
401 rval = xfs_dir2_isleaf(args, &v);
402 if (rval)
403 goto out_free;
404 if (v)
405 rval = xfs_dir2_leaf_lookup(args);
406 else
407 rval = xfs_dir2_node_lookup(args);
408
409out_check_rval:
410 if (rval == -EEXIST)
411 rval = 0;
412 if (!rval) {
413 *inum = args->inumber;
414 if (ci_name) {
415 ci_name->name = args->value;
416 ci_name->len = args->valuelen;
417 }
418 }
419out_free:
420 xfs_iunlock(dp, lock_mode);
421 kmem_free(args);
422 return rval;
423}
424
425/*
426 * Remove an entry from a directory.
427 */
428int
429xfs_dir_removename(
430 struct xfs_trans *tp,
431 struct xfs_inode *dp,
432 struct xfs_name *name,
433 xfs_ino_t ino,
434 xfs_extlen_t total) /* bmap's total block count */
435{
436 struct xfs_da_args *args;
437 int rval;
438 bool v;
439
440 ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
441 XFS_STATS_INC(dp->i_mount, xs_dir_remove);
442
443 args = kmem_zalloc(sizeof(*args), KM_NOFS);
444 if (!args)
445 return -ENOMEM;
446
447 args->geo = dp->i_mount->m_dir_geo;
448 args->name = name->name;
449 args->namelen = name->len;
450 args->filetype = name->type;
451 args->hashval = xfs_dir2_hashname(dp->i_mount, name);
452 args->inumber = ino;
453 args->dp = dp;
454 args->total = total;
455 args->whichfork = XFS_DATA_FORK;
456 args->trans = tp;
457
458 if (dp->i_df.if_format == XFS_DINODE_FMT_LOCAL) {
459 rval = xfs_dir2_sf_removename(args);
460 goto out_free;
461 }
462
463 rval = xfs_dir2_isblock(args, &v);
464 if (rval)
465 goto out_free;
466 if (v) {
467 rval = xfs_dir2_block_removename(args);
468 goto out_free;
469 }
470
471 rval = xfs_dir2_isleaf(args, &v);
472 if (rval)
473 goto out_free;
474 if (v)
475 rval = xfs_dir2_leaf_removename(args);
476 else
477 rval = xfs_dir2_node_removename(args);
478out_free:
479 kmem_free(args);
480 return rval;
481}
482
483/*
484 * Replace the inode number of a directory entry.
485 */
486int
487xfs_dir_replace(
488 struct xfs_trans *tp,
489 struct xfs_inode *dp,
490 const struct xfs_name *name, /* name of entry to replace */
491 xfs_ino_t inum, /* new inode number */
492 xfs_extlen_t total) /* bmap's total block count */
493{
494 struct xfs_da_args *args;
495 int rval;
496 bool v;
497
498 ASSERT(S_ISDIR(VFS_I(dp)->i_mode));
499
500 rval = xfs_dir_ino_validate(tp->t_mountp, inum);
501 if (rval)
502 return rval;
503
504 args = kmem_zalloc(sizeof(*args), KM_NOFS);
505 if (!args)
506 return -ENOMEM;
507
508 args->geo = dp->i_mount->m_dir_geo;
509 args->name = name->name;
510 args->namelen = name->len;
511 args->filetype = name->type;
512 args->hashval = xfs_dir2_hashname(dp->i_mount, name);
513 args->inumber = inum;
514 args->dp = dp;
515 args->total = total;
516 args->whichfork = XFS_DATA_FORK;
517 args->trans = tp;
518
519 if (dp->i_df.if_format == XFS_DINODE_FMT_LOCAL) {
520 rval = xfs_dir2_sf_replace(args);
521 goto out_free;
522 }
523
524 rval = xfs_dir2_isblock(args, &v);
525 if (rval)
526 goto out_free;
527 if (v) {
528 rval = xfs_dir2_block_replace(args);
529 goto out_free;
530 }
531
532 rval = xfs_dir2_isleaf(args, &v);
533 if (rval)
534 goto out_free;
535 if (v)
536 rval = xfs_dir2_leaf_replace(args);
537 else
538 rval = xfs_dir2_node_replace(args);
539out_free:
540 kmem_free(args);
541 return rval;
542}
543
544/*
545 * See if this entry can be added to the directory without allocating space.
546 */
547int
548xfs_dir_canenter(
549 xfs_trans_t *tp,
550 xfs_inode_t *dp,
551 struct xfs_name *name) /* name of entry to add */
552{
553 return xfs_dir_createname(tp, dp, name, 0, 0);
554}
555
556/*
557 * Utility routines.
558 */
559
560/*
561 * Add a block to the directory.
562 *
563 * This routine is for data and free blocks, not leaf/node blocks which are
564 * handled by xfs_da_grow_inode.
565 */
566int
567xfs_dir2_grow_inode(
568 struct xfs_da_args *args,
569 int space, /* v2 dir's space XFS_DIR2_xxx_SPACE */
570 xfs_dir2_db_t *dbp) /* out: block number added */
571{
572 struct xfs_inode *dp = args->dp;
573 struct xfs_mount *mp = dp->i_mount;
574 xfs_fileoff_t bno; /* directory offset of new block */
575 int count; /* count of filesystem blocks */
576 int error;
577
578 trace_xfs_dir2_grow_inode(args, space);
579
580 /*
581 * Set lowest possible block in the space requested.
582 */
583 bno = XFS_B_TO_FSBT(mp, space * XFS_DIR2_SPACE_SIZE);
584 count = args->geo->fsbcount;
585
586 error = xfs_da_grow_inode_int(args, &bno, count);
587 if (error)
588 return error;
589
590 *dbp = xfs_dir2_da_to_db(args->geo, (xfs_dablk_t)bno);
591
592 /*
593 * Update file's size if this is the data space and it grew.
594 */
595 if (space == XFS_DIR2_DATA_SPACE) {
596 xfs_fsize_t size; /* directory file (data) size */
597
598 size = XFS_FSB_TO_B(mp, bno + count);
599 if (size > dp->i_disk_size) {
600 dp->i_disk_size = size;
601 xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE);
602 }
603 }
604 return 0;
605}
606
607/*
608 * See if the directory is a single-block form directory.
609 */
610int
611xfs_dir2_isblock(
612 struct xfs_da_args *args,
613 bool *isblock)
614{
615 struct xfs_mount *mp = args->dp->i_mount;
616 xfs_fileoff_t eof;
617 int error;
618
619 error = xfs_bmap_last_offset(args->dp, &eof, XFS_DATA_FORK);
620 if (error)
621 return error;
622
623 *isblock = false;
624 if (XFS_FSB_TO_B(mp, eof) != args->geo->blksize)
625 return 0;
626
627 *isblock = true;
628 if (XFS_IS_CORRUPT(mp, args->dp->i_disk_size != args->geo->blksize))
629 return -EFSCORRUPTED;
630 return 0;
631}
632
633/*
634 * See if the directory is a single-leaf form directory.
635 */
636int
637xfs_dir2_isleaf(
638 struct xfs_da_args *args,
639 bool *isleaf)
640{
641 xfs_fileoff_t eof;
642 int error;
643
644 error = xfs_bmap_last_offset(args->dp, &eof, XFS_DATA_FORK);
645 if (error)
646 return error;
647
648 *isleaf = false;
649 if (eof != args->geo->leafblk + args->geo->fsbcount)
650 return 0;
651
652 *isleaf = true;
653 return 0;
654}
655
656/*
657 * Remove the given block from the directory.
658 * This routine is used for data and free blocks, leaf/node are done
659 * by xfs_da_shrink_inode.
660 */
661int
662xfs_dir2_shrink_inode(
663 struct xfs_da_args *args,
664 xfs_dir2_db_t db,
665 struct xfs_buf *bp)
666{
667 xfs_fileoff_t bno; /* directory file offset */
668 xfs_dablk_t da; /* directory file offset */
669 int done; /* bunmap is finished */
670 struct xfs_inode *dp;
671 int error;
672 struct xfs_mount *mp;
673 struct xfs_trans *tp;
674
675 trace_xfs_dir2_shrink_inode(args, db);
676
677 dp = args->dp;
678 mp = dp->i_mount;
679 tp = args->trans;
680 da = xfs_dir2_db_to_da(args->geo, db);
681
682 /* Unmap the fsblock(s). */
683 error = xfs_bunmapi(tp, dp, da, args->geo->fsbcount, 0, 0, &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_disk_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_disk_size = XFS_FSB_TO_B(mp, bno);
729 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
730 return 0;
731}
732
733/* Returns true if the directory entry name is valid. */
734bool
735xfs_dir2_namecheck(
736 const void *name,
737 size_t length)
738{
739 /*
740 * MAXNAMELEN includes the trailing null, but (name/length) leave it
741 * out, so use >= for the length check.
742 */
743 if (length >= MAXNAMELEN)
744 return false;
745
746 /* There shouldn't be any slashes or nulls here */
747 return !memchr(name, '/', length) && !memchr(name, 0, length);
748}
749
750xfs_dahash_t
751xfs_dir2_hashname(
752 struct xfs_mount *mp,
753 const struct xfs_name *name)
754{
755 if (unlikely(xfs_has_asciici(mp)))
756 return xfs_ascii_ci_hashname(name);
757 return xfs_da_hashname(name->name, name->len);
758}
759
760enum xfs_dacmp
761xfs_dir2_compname(
762 struct xfs_da_args *args,
763 const unsigned char *name,
764 int len)
765{
766 if (unlikely(xfs_has_asciici(args->dp->i_mount)))
767 return xfs_ascii_ci_compname(args, name, len);
768 return xfs_da_compname(args, name, len);
769}
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}