Loading...
1/*
2 * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
3 * Copyright (c) 2013 Red Hat, Inc.
4 * All Rights Reserved.
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License as
8 * published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it would be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18 */
19#include "xfs.h"
20#include "xfs_fs.h"
21#include "xfs_format.h"
22#include "xfs_log_format.h"
23#include "xfs_trans_resv.h"
24#include "xfs_mount.h"
25#include "xfs_da_format.h"
26#include "xfs_da_btree.h"
27#include "xfs_inode.h"
28#include "xfs_dir2.h"
29#include "xfs_dir2_priv.h"
30#include "xfs_error.h"
31#include "xfs_trans.h"
32#include "xfs_buf_item.h"
33#include "xfs_cksum.h"
34#include "xfs_log.h"
35
36/*
37 * Check the consistency of the data block.
38 * The input can also be a block-format directory.
39 * Return NULL if the buffer is good, otherwise the address of the error.
40 */
41xfs_failaddr_t
42__xfs_dir3_data_check(
43 struct xfs_inode *dp, /* incore inode pointer */
44 struct xfs_buf *bp) /* data block's buffer */
45{
46 xfs_dir2_dataptr_t addr; /* addr for leaf lookup */
47 xfs_dir2_data_free_t *bf; /* bestfree table */
48 xfs_dir2_block_tail_t *btp=NULL; /* block tail */
49 int count; /* count of entries found */
50 xfs_dir2_data_hdr_t *hdr; /* data block header */
51 xfs_dir2_data_entry_t *dep; /* data entry */
52 xfs_dir2_data_free_t *dfp; /* bestfree entry */
53 xfs_dir2_data_unused_t *dup; /* unused entry */
54 char *endp; /* end of useful data */
55 int freeseen; /* mask of bestfrees seen */
56 xfs_dahash_t hash; /* hash of current name */
57 int i; /* leaf index */
58 int lastfree; /* last entry was unused */
59 xfs_dir2_leaf_entry_t *lep=NULL; /* block leaf entries */
60 xfs_mount_t *mp; /* filesystem mount point */
61 char *p; /* current data position */
62 int stale; /* count of stale leaves */
63 struct xfs_name name;
64 const struct xfs_dir_ops *ops;
65 struct xfs_da_geometry *geo;
66
67 mp = bp->b_target->bt_mount;
68 geo = mp->m_dir_geo;
69
70 /*
71 * We can be passed a null dp here from a verifier, so we need to go the
72 * hard way to get them.
73 */
74 ops = xfs_dir_get_ops(mp, dp);
75
76 /*
77 * If this isn't a directory, or we don't get handed the dir ops,
78 * something is seriously wrong. Bail out.
79 */
80 if ((dp && !S_ISDIR(VFS_I(dp)->i_mode)) ||
81 ops != xfs_dir_get_ops(mp, NULL))
82 return __this_address;
83
84 hdr = bp->b_addr;
85 p = (char *)ops->data_entry_p(hdr);
86
87 switch (hdr->magic) {
88 case cpu_to_be32(XFS_DIR3_BLOCK_MAGIC):
89 case cpu_to_be32(XFS_DIR2_BLOCK_MAGIC):
90 btp = xfs_dir2_block_tail_p(geo, hdr);
91 lep = xfs_dir2_block_leaf_p(btp);
92
93 /*
94 * The number of leaf entries is limited by the size of the
95 * block and the amount of space used by the data entries.
96 * We don't know how much space is used by the data entries yet,
97 * so just ensure that the count falls somewhere inside the
98 * block right now.
99 */
100 if (be32_to_cpu(btp->count) >=
101 ((char *)btp - p) / sizeof(struct xfs_dir2_leaf_entry))
102 return __this_address;
103 break;
104 case cpu_to_be32(XFS_DIR3_DATA_MAGIC):
105 case cpu_to_be32(XFS_DIR2_DATA_MAGIC):
106 break;
107 default:
108 return __this_address;
109 }
110 endp = xfs_dir3_data_endp(geo, hdr);
111 if (!endp)
112 return __this_address;
113
114 /*
115 * Account for zero bestfree entries.
116 */
117 bf = ops->data_bestfree_p(hdr);
118 count = lastfree = freeseen = 0;
119 if (!bf[0].length) {
120 if (bf[0].offset)
121 return __this_address;
122 freeseen |= 1 << 0;
123 }
124 if (!bf[1].length) {
125 if (bf[1].offset)
126 return __this_address;
127 freeseen |= 1 << 1;
128 }
129 if (!bf[2].length) {
130 if (bf[2].offset)
131 return __this_address;
132 freeseen |= 1 << 2;
133 }
134
135 if (be16_to_cpu(bf[0].length) < be16_to_cpu(bf[1].length))
136 return __this_address;
137 if (be16_to_cpu(bf[1].length) < be16_to_cpu(bf[2].length))
138 return __this_address;
139 /*
140 * Loop over the data/unused entries.
141 */
142 while (p < endp) {
143 dup = (xfs_dir2_data_unused_t *)p;
144 /*
145 * If it's unused, look for the space in the bestfree table.
146 * If we find it, account for that, else make sure it
147 * doesn't need to be there.
148 */
149 if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
150 if (lastfree != 0)
151 return __this_address;
152 if (endp < p + be16_to_cpu(dup->length))
153 return __this_address;
154 if (be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup)) !=
155 (char *)dup - (char *)hdr)
156 return __this_address;
157 dfp = xfs_dir2_data_freefind(hdr, bf, dup);
158 if (dfp) {
159 i = (int)(dfp - bf);
160 if ((freeseen & (1 << i)) != 0)
161 return __this_address;
162 freeseen |= 1 << i;
163 } else {
164 if (be16_to_cpu(dup->length) >
165 be16_to_cpu(bf[2].length))
166 return __this_address;
167 }
168 p += be16_to_cpu(dup->length);
169 lastfree = 1;
170 continue;
171 }
172 /*
173 * It's a real entry. Validate the fields.
174 * If this is a block directory then make sure it's
175 * in the leaf section of the block.
176 * The linear search is crude but this is DEBUG code.
177 */
178 dep = (xfs_dir2_data_entry_t *)p;
179 if (dep->namelen == 0)
180 return __this_address;
181 if (xfs_dir_ino_validate(mp, be64_to_cpu(dep->inumber)))
182 return __this_address;
183 if (endp < p + ops->data_entsize(dep->namelen))
184 return __this_address;
185 if (be16_to_cpu(*ops->data_entry_tag_p(dep)) !=
186 (char *)dep - (char *)hdr)
187 return __this_address;
188 if (ops->data_get_ftype(dep) >= XFS_DIR3_FT_MAX)
189 return __this_address;
190 count++;
191 lastfree = 0;
192 if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
193 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)) {
194 addr = xfs_dir2_db_off_to_dataptr(geo, geo->datablk,
195 (xfs_dir2_data_aoff_t)
196 ((char *)dep - (char *)hdr));
197 name.name = dep->name;
198 name.len = dep->namelen;
199 hash = mp->m_dirnameops->hashname(&name);
200 for (i = 0; i < be32_to_cpu(btp->count); i++) {
201 if (be32_to_cpu(lep[i].address) == addr &&
202 be32_to_cpu(lep[i].hashval) == hash)
203 break;
204 }
205 if (i >= be32_to_cpu(btp->count))
206 return __this_address;
207 }
208 p += ops->data_entsize(dep->namelen);
209 }
210 /*
211 * Need to have seen all the entries and all the bestfree slots.
212 */
213 if (freeseen != 7)
214 return __this_address;
215 if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
216 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)) {
217 for (i = stale = 0; i < be32_to_cpu(btp->count); i++) {
218 if (lep[i].address ==
219 cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
220 stale++;
221 if (i > 0 && be32_to_cpu(lep[i].hashval) <
222 be32_to_cpu(lep[i - 1].hashval))
223 return __this_address;
224 }
225 if (count != be32_to_cpu(btp->count) - be32_to_cpu(btp->stale))
226 return __this_address;
227 if (stale != be32_to_cpu(btp->stale))
228 return __this_address;
229 }
230 return NULL;
231}
232
233#ifdef DEBUG
234void
235xfs_dir3_data_check(
236 struct xfs_inode *dp,
237 struct xfs_buf *bp)
238{
239 xfs_failaddr_t fa;
240
241 fa = __xfs_dir3_data_check(dp, bp);
242 if (!fa)
243 return;
244 xfs_corruption_error(__func__, XFS_ERRLEVEL_LOW, dp->i_mount,
245 bp->b_addr, __FILE__, __LINE__, fa);
246 ASSERT(0);
247}
248#endif
249
250static xfs_failaddr_t
251xfs_dir3_data_verify(
252 struct xfs_buf *bp)
253{
254 struct xfs_mount *mp = bp->b_target->bt_mount;
255 struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr;
256
257 if (xfs_sb_version_hascrc(&mp->m_sb)) {
258 if (hdr3->magic != cpu_to_be32(XFS_DIR3_DATA_MAGIC))
259 return __this_address;
260 if (!uuid_equal(&hdr3->uuid, &mp->m_sb.sb_meta_uuid))
261 return __this_address;
262 if (be64_to_cpu(hdr3->blkno) != bp->b_bn)
263 return __this_address;
264 if (!xfs_log_check_lsn(mp, be64_to_cpu(hdr3->lsn)))
265 return __this_address;
266 } else {
267 if (hdr3->magic != cpu_to_be32(XFS_DIR2_DATA_MAGIC))
268 return __this_address;
269 }
270 return __xfs_dir3_data_check(NULL, bp);
271}
272
273/*
274 * Readahead of the first block of the directory when it is opened is completely
275 * oblivious to the format of the directory. Hence we can either get a block
276 * format buffer or a data format buffer on readahead.
277 */
278static void
279xfs_dir3_data_reada_verify(
280 struct xfs_buf *bp)
281{
282 struct xfs_dir2_data_hdr *hdr = bp->b_addr;
283
284 switch (hdr->magic) {
285 case cpu_to_be32(XFS_DIR2_BLOCK_MAGIC):
286 case cpu_to_be32(XFS_DIR3_BLOCK_MAGIC):
287 bp->b_ops = &xfs_dir3_block_buf_ops;
288 bp->b_ops->verify_read(bp);
289 return;
290 case cpu_to_be32(XFS_DIR2_DATA_MAGIC):
291 case cpu_to_be32(XFS_DIR3_DATA_MAGIC):
292 bp->b_ops = &xfs_dir3_data_buf_ops;
293 bp->b_ops->verify_read(bp);
294 return;
295 default:
296 xfs_verifier_error(bp, -EFSCORRUPTED, __this_address);
297 break;
298 }
299}
300
301static void
302xfs_dir3_data_read_verify(
303 struct xfs_buf *bp)
304{
305 struct xfs_mount *mp = bp->b_target->bt_mount;
306 xfs_failaddr_t fa;
307
308 if (xfs_sb_version_hascrc(&mp->m_sb) &&
309 !xfs_buf_verify_cksum(bp, XFS_DIR3_DATA_CRC_OFF))
310 xfs_verifier_error(bp, -EFSBADCRC, __this_address);
311 else {
312 fa = xfs_dir3_data_verify(bp);
313 if (fa)
314 xfs_verifier_error(bp, -EFSCORRUPTED, fa);
315 }
316}
317
318static void
319xfs_dir3_data_write_verify(
320 struct xfs_buf *bp)
321{
322 struct xfs_mount *mp = bp->b_target->bt_mount;
323 struct xfs_buf_log_item *bip = bp->b_log_item;
324 struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr;
325 xfs_failaddr_t fa;
326
327 fa = xfs_dir3_data_verify(bp);
328 if (fa) {
329 xfs_verifier_error(bp, -EFSCORRUPTED, fa);
330 return;
331 }
332
333 if (!xfs_sb_version_hascrc(&mp->m_sb))
334 return;
335
336 if (bip)
337 hdr3->lsn = cpu_to_be64(bip->bli_item.li_lsn);
338
339 xfs_buf_update_cksum(bp, XFS_DIR3_DATA_CRC_OFF);
340}
341
342const struct xfs_buf_ops xfs_dir3_data_buf_ops = {
343 .name = "xfs_dir3_data",
344 .verify_read = xfs_dir3_data_read_verify,
345 .verify_write = xfs_dir3_data_write_verify,
346 .verify_struct = xfs_dir3_data_verify,
347};
348
349static const struct xfs_buf_ops xfs_dir3_data_reada_buf_ops = {
350 .name = "xfs_dir3_data_reada",
351 .verify_read = xfs_dir3_data_reada_verify,
352 .verify_write = xfs_dir3_data_write_verify,
353};
354
355
356int
357xfs_dir3_data_read(
358 struct xfs_trans *tp,
359 struct xfs_inode *dp,
360 xfs_dablk_t bno,
361 xfs_daddr_t mapped_bno,
362 struct xfs_buf **bpp)
363{
364 int err;
365
366 err = xfs_da_read_buf(tp, dp, bno, mapped_bno, bpp,
367 XFS_DATA_FORK, &xfs_dir3_data_buf_ops);
368 if (!err && tp && *bpp)
369 xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_DATA_BUF);
370 return err;
371}
372
373int
374xfs_dir3_data_readahead(
375 struct xfs_inode *dp,
376 xfs_dablk_t bno,
377 xfs_daddr_t mapped_bno)
378{
379 return xfs_da_reada_buf(dp, bno, mapped_bno,
380 XFS_DATA_FORK, &xfs_dir3_data_reada_buf_ops);
381}
382
383/*
384 * Given a data block and an unused entry from that block,
385 * return the bestfree entry if any that corresponds to it.
386 */
387xfs_dir2_data_free_t *
388xfs_dir2_data_freefind(
389 struct xfs_dir2_data_hdr *hdr, /* data block header */
390 struct xfs_dir2_data_free *bf, /* bestfree table pointer */
391 struct xfs_dir2_data_unused *dup) /* unused space */
392{
393 xfs_dir2_data_free_t *dfp; /* bestfree entry */
394 xfs_dir2_data_aoff_t off; /* offset value needed */
395#ifdef DEBUG
396 int matched; /* matched the value */
397 int seenzero; /* saw a 0 bestfree entry */
398#endif
399
400 off = (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr);
401
402#ifdef DEBUG
403 /*
404 * Validate some consistency in the bestfree table.
405 * Check order, non-overlapping entries, and if we find the
406 * one we're looking for it has to be exact.
407 */
408 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
409 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
410 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
411 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC));
412 for (dfp = &bf[0], seenzero = matched = 0;
413 dfp < &bf[XFS_DIR2_DATA_FD_COUNT];
414 dfp++) {
415 if (!dfp->offset) {
416 ASSERT(!dfp->length);
417 seenzero = 1;
418 continue;
419 }
420 ASSERT(seenzero == 0);
421 if (be16_to_cpu(dfp->offset) == off) {
422 matched = 1;
423 ASSERT(dfp->length == dup->length);
424 } else if (off < be16_to_cpu(dfp->offset))
425 ASSERT(off + be16_to_cpu(dup->length) <= be16_to_cpu(dfp->offset));
426 else
427 ASSERT(be16_to_cpu(dfp->offset) + be16_to_cpu(dfp->length) <= off);
428 ASSERT(matched || be16_to_cpu(dfp->length) >= be16_to_cpu(dup->length));
429 if (dfp > &bf[0])
430 ASSERT(be16_to_cpu(dfp[-1].length) >= be16_to_cpu(dfp[0].length));
431 }
432#endif
433 /*
434 * If this is smaller than the smallest bestfree entry,
435 * it can't be there since they're sorted.
436 */
437 if (be16_to_cpu(dup->length) <
438 be16_to_cpu(bf[XFS_DIR2_DATA_FD_COUNT - 1].length))
439 return NULL;
440 /*
441 * Look at the three bestfree entries for our guy.
442 */
443 for (dfp = &bf[0]; dfp < &bf[XFS_DIR2_DATA_FD_COUNT]; dfp++) {
444 if (!dfp->offset)
445 return NULL;
446 if (be16_to_cpu(dfp->offset) == off)
447 return dfp;
448 }
449 /*
450 * Didn't find it. This only happens if there are duplicate lengths.
451 */
452 return NULL;
453}
454
455/*
456 * Insert an unused-space entry into the bestfree table.
457 */
458xfs_dir2_data_free_t * /* entry inserted */
459xfs_dir2_data_freeinsert(
460 struct xfs_dir2_data_hdr *hdr, /* data block pointer */
461 struct xfs_dir2_data_free *dfp, /* bestfree table pointer */
462 struct xfs_dir2_data_unused *dup, /* unused space */
463 int *loghead) /* log the data header (out) */
464{
465 xfs_dir2_data_free_t new; /* new bestfree entry */
466
467 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
468 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
469 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
470 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC));
471
472 new.length = dup->length;
473 new.offset = cpu_to_be16((char *)dup - (char *)hdr);
474
475 /*
476 * Insert at position 0, 1, or 2; or not at all.
477 */
478 if (be16_to_cpu(new.length) > be16_to_cpu(dfp[0].length)) {
479 dfp[2] = dfp[1];
480 dfp[1] = dfp[0];
481 dfp[0] = new;
482 *loghead = 1;
483 return &dfp[0];
484 }
485 if (be16_to_cpu(new.length) > be16_to_cpu(dfp[1].length)) {
486 dfp[2] = dfp[1];
487 dfp[1] = new;
488 *loghead = 1;
489 return &dfp[1];
490 }
491 if (be16_to_cpu(new.length) > be16_to_cpu(dfp[2].length)) {
492 dfp[2] = new;
493 *loghead = 1;
494 return &dfp[2];
495 }
496 return NULL;
497}
498
499/*
500 * Remove a bestfree entry from the table.
501 */
502STATIC void
503xfs_dir2_data_freeremove(
504 struct xfs_dir2_data_hdr *hdr, /* data block header */
505 struct xfs_dir2_data_free *bf, /* bestfree table pointer */
506 struct xfs_dir2_data_free *dfp, /* bestfree entry pointer */
507 int *loghead) /* out: log data header */
508{
509
510 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
511 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
512 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
513 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC));
514
515 /*
516 * It's the first entry, slide the next 2 up.
517 */
518 if (dfp == &bf[0]) {
519 bf[0] = bf[1];
520 bf[1] = bf[2];
521 }
522 /*
523 * It's the second entry, slide the 3rd entry up.
524 */
525 else if (dfp == &bf[1])
526 bf[1] = bf[2];
527 /*
528 * Must be the last entry.
529 */
530 else
531 ASSERT(dfp == &bf[2]);
532 /*
533 * Clear the 3rd entry, must be zero now.
534 */
535 bf[2].length = 0;
536 bf[2].offset = 0;
537 *loghead = 1;
538}
539
540/*
541 * Given a data block, reconstruct its bestfree map.
542 */
543void
544xfs_dir2_data_freescan_int(
545 struct xfs_da_geometry *geo,
546 const struct xfs_dir_ops *ops,
547 struct xfs_dir2_data_hdr *hdr,
548 int *loghead)
549{
550 xfs_dir2_data_entry_t *dep; /* active data entry */
551 xfs_dir2_data_unused_t *dup; /* unused data entry */
552 struct xfs_dir2_data_free *bf;
553 char *endp; /* end of block's data */
554 char *p; /* current entry pointer */
555
556 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
557 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
558 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
559 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC));
560
561 /*
562 * Start by clearing the table.
563 */
564 bf = ops->data_bestfree_p(hdr);
565 memset(bf, 0, sizeof(*bf) * XFS_DIR2_DATA_FD_COUNT);
566 *loghead = 1;
567 /*
568 * Set up pointers.
569 */
570 p = (char *)ops->data_entry_p(hdr);
571 endp = xfs_dir3_data_endp(geo, hdr);
572 /*
573 * Loop over the block's entries.
574 */
575 while (p < endp) {
576 dup = (xfs_dir2_data_unused_t *)p;
577 /*
578 * If it's a free entry, insert it.
579 */
580 if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
581 ASSERT((char *)dup - (char *)hdr ==
582 be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup)));
583 xfs_dir2_data_freeinsert(hdr, bf, dup, loghead);
584 p += be16_to_cpu(dup->length);
585 }
586 /*
587 * For active entries, check their tags and skip them.
588 */
589 else {
590 dep = (xfs_dir2_data_entry_t *)p;
591 ASSERT((char *)dep - (char *)hdr ==
592 be16_to_cpu(*ops->data_entry_tag_p(dep)));
593 p += ops->data_entsize(dep->namelen);
594 }
595 }
596}
597
598void
599xfs_dir2_data_freescan(
600 struct xfs_inode *dp,
601 struct xfs_dir2_data_hdr *hdr,
602 int *loghead)
603{
604 return xfs_dir2_data_freescan_int(dp->i_mount->m_dir_geo, dp->d_ops,
605 hdr, loghead);
606}
607
608/*
609 * Initialize a data block at the given block number in the directory.
610 * Give back the buffer for the created block.
611 */
612int /* error */
613xfs_dir3_data_init(
614 xfs_da_args_t *args, /* directory operation args */
615 xfs_dir2_db_t blkno, /* logical dir block number */
616 struct xfs_buf **bpp) /* output block buffer */
617{
618 struct xfs_buf *bp; /* block buffer */
619 xfs_dir2_data_hdr_t *hdr; /* data block header */
620 xfs_inode_t *dp; /* incore directory inode */
621 xfs_dir2_data_unused_t *dup; /* unused entry pointer */
622 struct xfs_dir2_data_free *bf;
623 int error; /* error return value */
624 int i; /* bestfree index */
625 xfs_mount_t *mp; /* filesystem mount point */
626 xfs_trans_t *tp; /* transaction pointer */
627 int t; /* temp */
628
629 dp = args->dp;
630 mp = dp->i_mount;
631 tp = args->trans;
632 /*
633 * Get the buffer set up for the block.
634 */
635 error = xfs_da_get_buf(tp, dp, xfs_dir2_db_to_da(args->geo, blkno),
636 -1, &bp, XFS_DATA_FORK);
637 if (error)
638 return error;
639 bp->b_ops = &xfs_dir3_data_buf_ops;
640 xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_DATA_BUF);
641
642 /*
643 * Initialize the header.
644 */
645 hdr = bp->b_addr;
646 if (xfs_sb_version_hascrc(&mp->m_sb)) {
647 struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr;
648
649 memset(hdr3, 0, sizeof(*hdr3));
650 hdr3->magic = cpu_to_be32(XFS_DIR3_DATA_MAGIC);
651 hdr3->blkno = cpu_to_be64(bp->b_bn);
652 hdr3->owner = cpu_to_be64(dp->i_ino);
653 uuid_copy(&hdr3->uuid, &mp->m_sb.sb_meta_uuid);
654
655 } else
656 hdr->magic = cpu_to_be32(XFS_DIR2_DATA_MAGIC);
657
658 bf = dp->d_ops->data_bestfree_p(hdr);
659 bf[0].offset = cpu_to_be16(dp->d_ops->data_entry_offset);
660 for (i = 1; i < XFS_DIR2_DATA_FD_COUNT; i++) {
661 bf[i].length = 0;
662 bf[i].offset = 0;
663 }
664
665 /*
666 * Set up an unused entry for the block's body.
667 */
668 dup = dp->d_ops->data_unused_p(hdr);
669 dup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG);
670
671 t = args->geo->blksize - (uint)dp->d_ops->data_entry_offset;
672 bf[0].length = cpu_to_be16(t);
673 dup->length = cpu_to_be16(t);
674 *xfs_dir2_data_unused_tag_p(dup) = cpu_to_be16((char *)dup - (char *)hdr);
675 /*
676 * Log it and return it.
677 */
678 xfs_dir2_data_log_header(args, bp);
679 xfs_dir2_data_log_unused(args, bp, dup);
680 *bpp = bp;
681 return 0;
682}
683
684/*
685 * Log an active data entry from the block.
686 */
687void
688xfs_dir2_data_log_entry(
689 struct xfs_da_args *args,
690 struct xfs_buf *bp,
691 xfs_dir2_data_entry_t *dep) /* data entry pointer */
692{
693 struct xfs_dir2_data_hdr *hdr = bp->b_addr;
694
695 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
696 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
697 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
698 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC));
699
700 xfs_trans_log_buf(args->trans, bp, (uint)((char *)dep - (char *)hdr),
701 (uint)((char *)(args->dp->d_ops->data_entry_tag_p(dep) + 1) -
702 (char *)hdr - 1));
703}
704
705/*
706 * Log a data block header.
707 */
708void
709xfs_dir2_data_log_header(
710 struct xfs_da_args *args,
711 struct xfs_buf *bp)
712{
713#ifdef DEBUG
714 struct xfs_dir2_data_hdr *hdr = bp->b_addr;
715
716 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
717 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
718 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
719 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC));
720#endif
721
722 xfs_trans_log_buf(args->trans, bp, 0,
723 args->dp->d_ops->data_entry_offset - 1);
724}
725
726/*
727 * Log a data unused entry.
728 */
729void
730xfs_dir2_data_log_unused(
731 struct xfs_da_args *args,
732 struct xfs_buf *bp,
733 xfs_dir2_data_unused_t *dup) /* data unused pointer */
734{
735 xfs_dir2_data_hdr_t *hdr = bp->b_addr;
736
737 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
738 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
739 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
740 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC));
741
742 /*
743 * Log the first part of the unused entry.
744 */
745 xfs_trans_log_buf(args->trans, bp, (uint)((char *)dup - (char *)hdr),
746 (uint)((char *)&dup->length + sizeof(dup->length) -
747 1 - (char *)hdr));
748 /*
749 * Log the end (tag) of the unused entry.
750 */
751 xfs_trans_log_buf(args->trans, bp,
752 (uint)((char *)xfs_dir2_data_unused_tag_p(dup) - (char *)hdr),
753 (uint)((char *)xfs_dir2_data_unused_tag_p(dup) - (char *)hdr +
754 sizeof(xfs_dir2_data_off_t) - 1));
755}
756
757/*
758 * Make a byte range in the data block unused.
759 * Its current contents are unimportant.
760 */
761void
762xfs_dir2_data_make_free(
763 struct xfs_da_args *args,
764 struct xfs_buf *bp,
765 xfs_dir2_data_aoff_t offset, /* starting byte offset */
766 xfs_dir2_data_aoff_t len, /* length in bytes */
767 int *needlogp, /* out: log header */
768 int *needscanp) /* out: regen bestfree */
769{
770 xfs_dir2_data_hdr_t *hdr; /* data block pointer */
771 xfs_dir2_data_free_t *dfp; /* bestfree pointer */
772 char *endptr; /* end of data area */
773 int needscan; /* need to regen bestfree */
774 xfs_dir2_data_unused_t *newdup; /* new unused entry */
775 xfs_dir2_data_unused_t *postdup; /* unused entry after us */
776 xfs_dir2_data_unused_t *prevdup; /* unused entry before us */
777 struct xfs_dir2_data_free *bf;
778
779 hdr = bp->b_addr;
780
781 /*
782 * Figure out where the end of the data area is.
783 */
784 endptr = xfs_dir3_data_endp(args->geo, hdr);
785 ASSERT(endptr != NULL);
786
787 /*
788 * If this isn't the start of the block, then back up to
789 * the previous entry and see if it's free.
790 */
791 if (offset > args->dp->d_ops->data_entry_offset) {
792 __be16 *tagp; /* tag just before us */
793
794 tagp = (__be16 *)((char *)hdr + offset) - 1;
795 prevdup = (xfs_dir2_data_unused_t *)((char *)hdr + be16_to_cpu(*tagp));
796 if (be16_to_cpu(prevdup->freetag) != XFS_DIR2_DATA_FREE_TAG)
797 prevdup = NULL;
798 } else
799 prevdup = NULL;
800 /*
801 * If this isn't the end of the block, see if the entry after
802 * us is free.
803 */
804 if ((char *)hdr + offset + len < endptr) {
805 postdup =
806 (xfs_dir2_data_unused_t *)((char *)hdr + offset + len);
807 if (be16_to_cpu(postdup->freetag) != XFS_DIR2_DATA_FREE_TAG)
808 postdup = NULL;
809 } else
810 postdup = NULL;
811 ASSERT(*needscanp == 0);
812 needscan = 0;
813 /*
814 * Previous and following entries are both free,
815 * merge everything into a single free entry.
816 */
817 bf = args->dp->d_ops->data_bestfree_p(hdr);
818 if (prevdup && postdup) {
819 xfs_dir2_data_free_t *dfp2; /* another bestfree pointer */
820
821 /*
822 * See if prevdup and/or postdup are in bestfree table.
823 */
824 dfp = xfs_dir2_data_freefind(hdr, bf, prevdup);
825 dfp2 = xfs_dir2_data_freefind(hdr, bf, postdup);
826 /*
827 * We need a rescan unless there are exactly 2 free entries
828 * namely our two. Then we know what's happening, otherwise
829 * since the third bestfree is there, there might be more
830 * entries.
831 */
832 needscan = (bf[2].length != 0);
833 /*
834 * Fix up the new big freespace.
835 */
836 be16_add_cpu(&prevdup->length, len + be16_to_cpu(postdup->length));
837 *xfs_dir2_data_unused_tag_p(prevdup) =
838 cpu_to_be16((char *)prevdup - (char *)hdr);
839 xfs_dir2_data_log_unused(args, bp, prevdup);
840 if (!needscan) {
841 /*
842 * Has to be the case that entries 0 and 1 are
843 * dfp and dfp2 (don't know which is which), and
844 * entry 2 is empty.
845 * Remove entry 1 first then entry 0.
846 */
847 ASSERT(dfp && dfp2);
848 if (dfp == &bf[1]) {
849 dfp = &bf[0];
850 ASSERT(dfp2 == dfp);
851 dfp2 = &bf[1];
852 }
853 xfs_dir2_data_freeremove(hdr, bf, dfp2, needlogp);
854 xfs_dir2_data_freeremove(hdr, bf, dfp, needlogp);
855 /*
856 * Now insert the new entry.
857 */
858 dfp = xfs_dir2_data_freeinsert(hdr, bf, prevdup,
859 needlogp);
860 ASSERT(dfp == &bf[0]);
861 ASSERT(dfp->length == prevdup->length);
862 ASSERT(!dfp[1].length);
863 ASSERT(!dfp[2].length);
864 }
865 }
866 /*
867 * The entry before us is free, merge with it.
868 */
869 else if (prevdup) {
870 dfp = xfs_dir2_data_freefind(hdr, bf, prevdup);
871 be16_add_cpu(&prevdup->length, len);
872 *xfs_dir2_data_unused_tag_p(prevdup) =
873 cpu_to_be16((char *)prevdup - (char *)hdr);
874 xfs_dir2_data_log_unused(args, bp, prevdup);
875 /*
876 * If the previous entry was in the table, the new entry
877 * is longer, so it will be in the table too. Remove
878 * the old one and add the new one.
879 */
880 if (dfp) {
881 xfs_dir2_data_freeremove(hdr, bf, dfp, needlogp);
882 xfs_dir2_data_freeinsert(hdr, bf, prevdup, needlogp);
883 }
884 /*
885 * Otherwise we need a scan if the new entry is big enough.
886 */
887 else {
888 needscan = be16_to_cpu(prevdup->length) >
889 be16_to_cpu(bf[2].length);
890 }
891 }
892 /*
893 * The following entry is free, merge with it.
894 */
895 else if (postdup) {
896 dfp = xfs_dir2_data_freefind(hdr, bf, postdup);
897 newdup = (xfs_dir2_data_unused_t *)((char *)hdr + offset);
898 newdup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG);
899 newdup->length = cpu_to_be16(len + be16_to_cpu(postdup->length));
900 *xfs_dir2_data_unused_tag_p(newdup) =
901 cpu_to_be16((char *)newdup - (char *)hdr);
902 xfs_dir2_data_log_unused(args, bp, newdup);
903 /*
904 * If the following entry was in the table, the new entry
905 * is longer, so it will be in the table too. Remove
906 * the old one and add the new one.
907 */
908 if (dfp) {
909 xfs_dir2_data_freeremove(hdr, bf, dfp, needlogp);
910 xfs_dir2_data_freeinsert(hdr, bf, newdup, needlogp);
911 }
912 /*
913 * Otherwise we need a scan if the new entry is big enough.
914 */
915 else {
916 needscan = be16_to_cpu(newdup->length) >
917 be16_to_cpu(bf[2].length);
918 }
919 }
920 /*
921 * Neither neighbor is free. Make a new entry.
922 */
923 else {
924 newdup = (xfs_dir2_data_unused_t *)((char *)hdr + offset);
925 newdup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG);
926 newdup->length = cpu_to_be16(len);
927 *xfs_dir2_data_unused_tag_p(newdup) =
928 cpu_to_be16((char *)newdup - (char *)hdr);
929 xfs_dir2_data_log_unused(args, bp, newdup);
930 xfs_dir2_data_freeinsert(hdr, bf, newdup, needlogp);
931 }
932 *needscanp = needscan;
933}
934
935/* Check our free data for obvious signs of corruption. */
936static inline xfs_failaddr_t
937xfs_dir2_data_check_free(
938 struct xfs_dir2_data_hdr *hdr,
939 struct xfs_dir2_data_unused *dup,
940 xfs_dir2_data_aoff_t offset,
941 xfs_dir2_data_aoff_t len)
942{
943 if (hdr->magic != cpu_to_be32(XFS_DIR2_DATA_MAGIC) &&
944 hdr->magic != cpu_to_be32(XFS_DIR3_DATA_MAGIC) &&
945 hdr->magic != cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) &&
946 hdr->magic != cpu_to_be32(XFS_DIR3_BLOCK_MAGIC))
947 return __this_address;
948 if (be16_to_cpu(dup->freetag) != XFS_DIR2_DATA_FREE_TAG)
949 return __this_address;
950 if (offset < (char *)dup - (char *)hdr)
951 return __this_address;
952 if (offset + len > (char *)dup + be16_to_cpu(dup->length) - (char *)hdr)
953 return __this_address;
954 if ((char *)dup - (char *)hdr !=
955 be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup)))
956 return __this_address;
957 return NULL;
958}
959
960/* Sanity-check a new bestfree entry. */
961static inline xfs_failaddr_t
962xfs_dir2_data_check_new_free(
963 struct xfs_dir2_data_hdr *hdr,
964 struct xfs_dir2_data_free *dfp,
965 struct xfs_dir2_data_unused *newdup)
966{
967 if (dfp == NULL)
968 return __this_address;
969 if (dfp->length != newdup->length)
970 return __this_address;
971 if (be16_to_cpu(dfp->offset) != (char *)newdup - (char *)hdr)
972 return __this_address;
973 return NULL;
974}
975
976/*
977 * Take a byte range out of an existing unused space and make it un-free.
978 */
979int
980xfs_dir2_data_use_free(
981 struct xfs_da_args *args,
982 struct xfs_buf *bp,
983 xfs_dir2_data_unused_t *dup, /* unused entry */
984 xfs_dir2_data_aoff_t offset, /* starting offset to use */
985 xfs_dir2_data_aoff_t len, /* length to use */
986 int *needlogp, /* out: need to log header */
987 int *needscanp) /* out: need regen bestfree */
988{
989 xfs_dir2_data_hdr_t *hdr; /* data block header */
990 xfs_dir2_data_free_t *dfp; /* bestfree pointer */
991 xfs_dir2_data_unused_t *newdup; /* new unused entry */
992 xfs_dir2_data_unused_t *newdup2; /* another new unused entry */
993 struct xfs_dir2_data_free *bf;
994 xfs_failaddr_t fa;
995 int matchback; /* matches end of freespace */
996 int matchfront; /* matches start of freespace */
997 int needscan; /* need to regen bestfree */
998 int oldlen; /* old unused entry's length */
999
1000 hdr = bp->b_addr;
1001 fa = xfs_dir2_data_check_free(hdr, dup, offset, len);
1002 if (fa)
1003 goto corrupt;
1004 /*
1005 * Look up the entry in the bestfree table.
1006 */
1007 oldlen = be16_to_cpu(dup->length);
1008 bf = args->dp->d_ops->data_bestfree_p(hdr);
1009 dfp = xfs_dir2_data_freefind(hdr, bf, dup);
1010 ASSERT(dfp || oldlen <= be16_to_cpu(bf[2].length));
1011 /*
1012 * Check for alignment with front and back of the entry.
1013 */
1014 matchfront = (char *)dup - (char *)hdr == offset;
1015 matchback = (char *)dup + oldlen - (char *)hdr == offset + len;
1016 ASSERT(*needscanp == 0);
1017 needscan = 0;
1018 /*
1019 * If we matched it exactly we just need to get rid of it from
1020 * the bestfree table.
1021 */
1022 if (matchfront && matchback) {
1023 if (dfp) {
1024 needscan = (bf[2].offset != 0);
1025 if (!needscan)
1026 xfs_dir2_data_freeremove(hdr, bf, dfp,
1027 needlogp);
1028 }
1029 }
1030 /*
1031 * We match the first part of the entry.
1032 * Make a new entry with the remaining freespace.
1033 */
1034 else if (matchfront) {
1035 newdup = (xfs_dir2_data_unused_t *)((char *)hdr + offset + len);
1036 newdup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG);
1037 newdup->length = cpu_to_be16(oldlen - len);
1038 *xfs_dir2_data_unused_tag_p(newdup) =
1039 cpu_to_be16((char *)newdup - (char *)hdr);
1040 xfs_dir2_data_log_unused(args, bp, newdup);
1041 /*
1042 * If it was in the table, remove it and add the new one.
1043 */
1044 if (dfp) {
1045 xfs_dir2_data_freeremove(hdr, bf, dfp, needlogp);
1046 dfp = xfs_dir2_data_freeinsert(hdr, bf, newdup,
1047 needlogp);
1048 fa = xfs_dir2_data_check_new_free(hdr, dfp, newdup);
1049 if (fa)
1050 goto corrupt;
1051 /*
1052 * If we got inserted at the last slot,
1053 * that means we don't know if there was a better
1054 * choice for the last slot, or not. Rescan.
1055 */
1056 needscan = dfp == &bf[2];
1057 }
1058 }
1059 /*
1060 * We match the last part of the entry.
1061 * Trim the allocated space off the tail of the entry.
1062 */
1063 else if (matchback) {
1064 newdup = dup;
1065 newdup->length = cpu_to_be16(((char *)hdr + offset) - (char *)newdup);
1066 *xfs_dir2_data_unused_tag_p(newdup) =
1067 cpu_to_be16((char *)newdup - (char *)hdr);
1068 xfs_dir2_data_log_unused(args, bp, newdup);
1069 /*
1070 * If it was in the table, remove it and add the new one.
1071 */
1072 if (dfp) {
1073 xfs_dir2_data_freeremove(hdr, bf, dfp, needlogp);
1074 dfp = xfs_dir2_data_freeinsert(hdr, bf, newdup,
1075 needlogp);
1076 fa = xfs_dir2_data_check_new_free(hdr, dfp, newdup);
1077 if (fa)
1078 goto corrupt;
1079 /*
1080 * If we got inserted at the last slot,
1081 * that means we don't know if there was a better
1082 * choice for the last slot, or not. Rescan.
1083 */
1084 needscan = dfp == &bf[2];
1085 }
1086 }
1087 /*
1088 * Poking out the middle of an entry.
1089 * Make two new entries.
1090 */
1091 else {
1092 newdup = dup;
1093 newdup->length = cpu_to_be16(((char *)hdr + offset) - (char *)newdup);
1094 *xfs_dir2_data_unused_tag_p(newdup) =
1095 cpu_to_be16((char *)newdup - (char *)hdr);
1096 xfs_dir2_data_log_unused(args, bp, newdup);
1097 newdup2 = (xfs_dir2_data_unused_t *)((char *)hdr + offset + len);
1098 newdup2->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG);
1099 newdup2->length = cpu_to_be16(oldlen - len - be16_to_cpu(newdup->length));
1100 *xfs_dir2_data_unused_tag_p(newdup2) =
1101 cpu_to_be16((char *)newdup2 - (char *)hdr);
1102 xfs_dir2_data_log_unused(args, bp, newdup2);
1103 /*
1104 * If the old entry was in the table, we need to scan
1105 * if the 3rd entry was valid, since these entries
1106 * are smaller than the old one.
1107 * If we don't need to scan that means there were 1 or 2
1108 * entries in the table, and removing the old and adding
1109 * the 2 new will work.
1110 */
1111 if (dfp) {
1112 needscan = (bf[2].length != 0);
1113 if (!needscan) {
1114 xfs_dir2_data_freeremove(hdr, bf, dfp,
1115 needlogp);
1116 xfs_dir2_data_freeinsert(hdr, bf, newdup,
1117 needlogp);
1118 xfs_dir2_data_freeinsert(hdr, bf, newdup2,
1119 needlogp);
1120 }
1121 }
1122 }
1123 *needscanp = needscan;
1124 return 0;
1125corrupt:
1126 xfs_corruption_error(__func__, XFS_ERRLEVEL_LOW, args->dp->i_mount,
1127 hdr, __FILE__, __LINE__, fa);
1128 return -EFSCORRUPTED;
1129}
1130
1131/* Find the end of the entry data in a data/block format dir block. */
1132void *
1133xfs_dir3_data_endp(
1134 struct xfs_da_geometry *geo,
1135 struct xfs_dir2_data_hdr *hdr)
1136{
1137 switch (hdr->magic) {
1138 case cpu_to_be32(XFS_DIR3_BLOCK_MAGIC):
1139 case cpu_to_be32(XFS_DIR2_BLOCK_MAGIC):
1140 return xfs_dir2_block_leaf_p(xfs_dir2_block_tail_p(geo, hdr));
1141 case cpu_to_be32(XFS_DIR3_DATA_MAGIC):
1142 case cpu_to_be32(XFS_DIR2_DATA_MAGIC):
1143 return (char *)hdr + geo->blksize;
1144 default:
1145 return NULL;
1146 }
1147}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
4 * Copyright (c) 2013 Red Hat, Inc.
5 * All Rights Reserved.
6 */
7#include "xfs.h"
8#include "xfs_fs.h"
9#include "xfs_shared.h"
10#include "xfs_format.h"
11#include "xfs_log_format.h"
12#include "xfs_trans_resv.h"
13#include "xfs_mount.h"
14#include "xfs_inode.h"
15#include "xfs_dir2.h"
16#include "xfs_dir2_priv.h"
17#include "xfs_error.h"
18#include "xfs_trans.h"
19#include "xfs_buf_item.h"
20#include "xfs_log.h"
21
22static xfs_failaddr_t xfs_dir2_data_freefind_verify(
23 struct xfs_dir2_data_hdr *hdr, struct xfs_dir2_data_free *bf,
24 struct xfs_dir2_data_unused *dup,
25 struct xfs_dir2_data_free **bf_ent);
26
27struct xfs_dir2_data_free *
28xfs_dir2_data_bestfree_p(
29 struct xfs_mount *mp,
30 struct xfs_dir2_data_hdr *hdr)
31{
32 if (xfs_has_crc(mp))
33 return ((struct xfs_dir3_data_hdr *)hdr)->best_free;
34 return hdr->bestfree;
35}
36
37/*
38 * Pointer to an entry's tag word.
39 */
40__be16 *
41xfs_dir2_data_entry_tag_p(
42 struct xfs_mount *mp,
43 struct xfs_dir2_data_entry *dep)
44{
45 return (__be16 *)((char *)dep +
46 xfs_dir2_data_entsize(mp, dep->namelen) - sizeof(__be16));
47}
48
49uint8_t
50xfs_dir2_data_get_ftype(
51 struct xfs_mount *mp,
52 struct xfs_dir2_data_entry *dep)
53{
54 if (xfs_has_ftype(mp)) {
55 uint8_t ftype = dep->name[dep->namelen];
56
57 if (likely(ftype < XFS_DIR3_FT_MAX))
58 return ftype;
59 }
60
61 return XFS_DIR3_FT_UNKNOWN;
62}
63
64void
65xfs_dir2_data_put_ftype(
66 struct xfs_mount *mp,
67 struct xfs_dir2_data_entry *dep,
68 uint8_t ftype)
69{
70 ASSERT(ftype < XFS_DIR3_FT_MAX);
71 ASSERT(dep->namelen != 0);
72
73 if (xfs_has_ftype(mp))
74 dep->name[dep->namelen] = ftype;
75}
76
77/*
78 * The number of leaf entries is limited by the size of the block and the amount
79 * of space used by the data entries. We don't know how much space is used by
80 * the data entries yet, so just ensure that the count falls somewhere inside
81 * the block right now.
82 */
83static inline unsigned int
84xfs_dir2_data_max_leaf_entries(
85 struct xfs_da_geometry *geo)
86{
87 return (geo->blksize - sizeof(struct xfs_dir2_block_tail) -
88 geo->data_entry_offset) /
89 sizeof(struct xfs_dir2_leaf_entry);
90}
91
92/*
93 * Check the consistency of the data block.
94 * The input can also be a block-format directory.
95 * Return NULL if the buffer is good, otherwise the address of the error.
96 */
97xfs_failaddr_t
98__xfs_dir3_data_check(
99 struct xfs_inode *dp, /* incore inode pointer */
100 struct xfs_buf *bp) /* data block's buffer */
101{
102 xfs_dir2_dataptr_t addr; /* addr for leaf lookup */
103 xfs_dir2_data_free_t *bf; /* bestfree table */
104 xfs_dir2_block_tail_t *btp=NULL; /* block tail */
105 int count; /* count of entries found */
106 xfs_dir2_data_hdr_t *hdr; /* data block header */
107 xfs_dir2_data_free_t *dfp; /* bestfree entry */
108 int freeseen; /* mask of bestfrees seen */
109 xfs_dahash_t hash; /* hash of current name */
110 int i; /* leaf index */
111 int lastfree; /* last entry was unused */
112 xfs_dir2_leaf_entry_t *lep=NULL; /* block leaf entries */
113 struct xfs_mount *mp = bp->b_mount;
114 int stale; /* count of stale leaves */
115 struct xfs_name name;
116 unsigned int offset;
117 unsigned int end;
118 struct xfs_da_geometry *geo = mp->m_dir_geo;
119
120 /*
121 * If this isn't a directory, something is seriously wrong. Bail out.
122 */
123 if (dp && !S_ISDIR(VFS_I(dp)->i_mode))
124 return __this_address;
125
126 hdr = bp->b_addr;
127 offset = geo->data_entry_offset;
128
129 switch (hdr->magic) {
130 case cpu_to_be32(XFS_DIR3_BLOCK_MAGIC):
131 case cpu_to_be32(XFS_DIR2_BLOCK_MAGIC):
132 btp = xfs_dir2_block_tail_p(geo, hdr);
133 lep = xfs_dir2_block_leaf_p(btp);
134
135 if (be32_to_cpu(btp->count) >=
136 xfs_dir2_data_max_leaf_entries(geo))
137 return __this_address;
138 break;
139 case cpu_to_be32(XFS_DIR3_DATA_MAGIC):
140 case cpu_to_be32(XFS_DIR2_DATA_MAGIC):
141 break;
142 default:
143 return __this_address;
144 }
145 end = xfs_dir3_data_end_offset(geo, hdr);
146 if (!end)
147 return __this_address;
148
149 /*
150 * Account for zero bestfree entries.
151 */
152 bf = xfs_dir2_data_bestfree_p(mp, hdr);
153 count = lastfree = freeseen = 0;
154 if (!bf[0].length) {
155 if (bf[0].offset)
156 return __this_address;
157 freeseen |= 1 << 0;
158 }
159 if (!bf[1].length) {
160 if (bf[1].offset)
161 return __this_address;
162 freeseen |= 1 << 1;
163 }
164 if (!bf[2].length) {
165 if (bf[2].offset)
166 return __this_address;
167 freeseen |= 1 << 2;
168 }
169
170 if (be16_to_cpu(bf[0].length) < be16_to_cpu(bf[1].length))
171 return __this_address;
172 if (be16_to_cpu(bf[1].length) < be16_to_cpu(bf[2].length))
173 return __this_address;
174 /*
175 * Loop over the data/unused entries.
176 */
177 while (offset < end) {
178 struct xfs_dir2_data_unused *dup = bp->b_addr + offset;
179 struct xfs_dir2_data_entry *dep = bp->b_addr + offset;
180
181 /*
182 * If it's unused, look for the space in the bestfree table.
183 * If we find it, account for that, else make sure it
184 * doesn't need to be there.
185 */
186 if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
187 xfs_failaddr_t fa;
188
189 if (lastfree != 0)
190 return __this_address;
191 if (offset + be16_to_cpu(dup->length) > end)
192 return __this_address;
193 if (be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup)) !=
194 offset)
195 return __this_address;
196 fa = xfs_dir2_data_freefind_verify(hdr, bf, dup, &dfp);
197 if (fa)
198 return fa;
199 if (dfp) {
200 i = (int)(dfp - bf);
201 if ((freeseen & (1 << i)) != 0)
202 return __this_address;
203 freeseen |= 1 << i;
204 } else {
205 if (be16_to_cpu(dup->length) >
206 be16_to_cpu(bf[2].length))
207 return __this_address;
208 }
209 offset += be16_to_cpu(dup->length);
210 lastfree = 1;
211 continue;
212 }
213 /*
214 * It's a real entry. Validate the fields.
215 * If this is a block directory then make sure it's
216 * in the leaf section of the block.
217 * The linear search is crude but this is DEBUG code.
218 */
219 if (dep->namelen == 0)
220 return __this_address;
221 if (!xfs_verify_dir_ino(mp, be64_to_cpu(dep->inumber)))
222 return __this_address;
223 if (offset + xfs_dir2_data_entsize(mp, dep->namelen) > end)
224 return __this_address;
225 if (be16_to_cpu(*xfs_dir2_data_entry_tag_p(mp, dep)) != offset)
226 return __this_address;
227 if (xfs_dir2_data_get_ftype(mp, dep) >= XFS_DIR3_FT_MAX)
228 return __this_address;
229 count++;
230 lastfree = 0;
231 if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
232 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)) {
233 addr = xfs_dir2_db_off_to_dataptr(geo, geo->datablk,
234 (xfs_dir2_data_aoff_t)
235 ((char *)dep - (char *)hdr));
236 name.name = dep->name;
237 name.len = dep->namelen;
238 hash = xfs_dir2_hashname(mp, &name);
239 for (i = 0; i < be32_to_cpu(btp->count); i++) {
240 if (be32_to_cpu(lep[i].address) == addr &&
241 be32_to_cpu(lep[i].hashval) == hash)
242 break;
243 }
244 if (i >= be32_to_cpu(btp->count))
245 return __this_address;
246 }
247 offset += xfs_dir2_data_entsize(mp, dep->namelen);
248 }
249 /*
250 * Need to have seen all the entries and all the bestfree slots.
251 */
252 if (freeseen != 7)
253 return __this_address;
254 if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
255 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)) {
256 for (i = stale = 0; i < be32_to_cpu(btp->count); i++) {
257 if (lep[i].address ==
258 cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
259 stale++;
260 if (i > 0 && be32_to_cpu(lep[i].hashval) <
261 be32_to_cpu(lep[i - 1].hashval))
262 return __this_address;
263 }
264 if (count != be32_to_cpu(btp->count) - be32_to_cpu(btp->stale))
265 return __this_address;
266 if (stale != be32_to_cpu(btp->stale))
267 return __this_address;
268 }
269 return NULL;
270}
271
272#ifdef DEBUG
273void
274xfs_dir3_data_check(
275 struct xfs_inode *dp,
276 struct xfs_buf *bp)
277{
278 xfs_failaddr_t fa;
279
280 fa = __xfs_dir3_data_check(dp, bp);
281 if (!fa)
282 return;
283 xfs_corruption_error(__func__, XFS_ERRLEVEL_LOW, dp->i_mount,
284 bp->b_addr, BBTOB(bp->b_length), __FILE__, __LINE__,
285 fa);
286 ASSERT(0);
287}
288#endif
289
290static xfs_failaddr_t
291xfs_dir3_data_verify(
292 struct xfs_buf *bp)
293{
294 struct xfs_mount *mp = bp->b_mount;
295 struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr;
296
297 if (!xfs_verify_magic(bp, hdr3->magic))
298 return __this_address;
299
300 if (xfs_has_crc(mp)) {
301 if (!uuid_equal(&hdr3->uuid, &mp->m_sb.sb_meta_uuid))
302 return __this_address;
303 if (be64_to_cpu(hdr3->blkno) != xfs_buf_daddr(bp))
304 return __this_address;
305 if (!xfs_log_check_lsn(mp, be64_to_cpu(hdr3->lsn)))
306 return __this_address;
307 }
308 return __xfs_dir3_data_check(NULL, bp);
309}
310
311/*
312 * Readahead of the first block of the directory when it is opened is completely
313 * oblivious to the format of the directory. Hence we can either get a block
314 * format buffer or a data format buffer on readahead.
315 */
316static void
317xfs_dir3_data_reada_verify(
318 struct xfs_buf *bp)
319{
320 struct xfs_dir2_data_hdr *hdr = bp->b_addr;
321
322 switch (hdr->magic) {
323 case cpu_to_be32(XFS_DIR2_BLOCK_MAGIC):
324 case cpu_to_be32(XFS_DIR3_BLOCK_MAGIC):
325 bp->b_ops = &xfs_dir3_block_buf_ops;
326 bp->b_ops->verify_read(bp);
327 return;
328 case cpu_to_be32(XFS_DIR2_DATA_MAGIC):
329 case cpu_to_be32(XFS_DIR3_DATA_MAGIC):
330 bp->b_ops = &xfs_dir3_data_buf_ops;
331 bp->b_ops->verify_read(bp);
332 return;
333 default:
334 xfs_verifier_error(bp, -EFSCORRUPTED, __this_address);
335 break;
336 }
337}
338
339static void
340xfs_dir3_data_read_verify(
341 struct xfs_buf *bp)
342{
343 struct xfs_mount *mp = bp->b_mount;
344 xfs_failaddr_t fa;
345
346 if (xfs_has_crc(mp) &&
347 !xfs_buf_verify_cksum(bp, XFS_DIR3_DATA_CRC_OFF))
348 xfs_verifier_error(bp, -EFSBADCRC, __this_address);
349 else {
350 fa = xfs_dir3_data_verify(bp);
351 if (fa)
352 xfs_verifier_error(bp, -EFSCORRUPTED, fa);
353 }
354}
355
356static void
357xfs_dir3_data_write_verify(
358 struct xfs_buf *bp)
359{
360 struct xfs_mount *mp = bp->b_mount;
361 struct xfs_buf_log_item *bip = bp->b_log_item;
362 struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr;
363 xfs_failaddr_t fa;
364
365 fa = xfs_dir3_data_verify(bp);
366 if (fa) {
367 xfs_verifier_error(bp, -EFSCORRUPTED, fa);
368 return;
369 }
370
371 if (!xfs_has_crc(mp))
372 return;
373
374 if (bip)
375 hdr3->lsn = cpu_to_be64(bip->bli_item.li_lsn);
376
377 xfs_buf_update_cksum(bp, XFS_DIR3_DATA_CRC_OFF);
378}
379
380const struct xfs_buf_ops xfs_dir3_data_buf_ops = {
381 .name = "xfs_dir3_data",
382 .magic = { cpu_to_be32(XFS_DIR2_DATA_MAGIC),
383 cpu_to_be32(XFS_DIR3_DATA_MAGIC) },
384 .verify_read = xfs_dir3_data_read_verify,
385 .verify_write = xfs_dir3_data_write_verify,
386 .verify_struct = xfs_dir3_data_verify,
387};
388
389static const struct xfs_buf_ops xfs_dir3_data_reada_buf_ops = {
390 .name = "xfs_dir3_data_reada",
391 .magic = { cpu_to_be32(XFS_DIR2_DATA_MAGIC),
392 cpu_to_be32(XFS_DIR3_DATA_MAGIC) },
393 .verify_read = xfs_dir3_data_reada_verify,
394 .verify_write = xfs_dir3_data_write_verify,
395};
396
397static xfs_failaddr_t
398xfs_dir3_data_header_check(
399 struct xfs_inode *dp,
400 struct xfs_buf *bp)
401{
402 struct xfs_mount *mp = dp->i_mount;
403
404 if (xfs_has_crc(mp)) {
405 struct xfs_dir3_data_hdr *hdr3 = bp->b_addr;
406
407 if (be64_to_cpu(hdr3->hdr.owner) != dp->i_ino)
408 return __this_address;
409 }
410
411 return NULL;
412}
413
414int
415xfs_dir3_data_read(
416 struct xfs_trans *tp,
417 struct xfs_inode *dp,
418 xfs_dablk_t bno,
419 unsigned int flags,
420 struct xfs_buf **bpp)
421{
422 xfs_failaddr_t fa;
423 int err;
424
425 err = xfs_da_read_buf(tp, dp, bno, flags, bpp, XFS_DATA_FORK,
426 &xfs_dir3_data_buf_ops);
427 if (err || !*bpp)
428 return err;
429
430 /* Check things that we can't do in the verifier. */
431 fa = xfs_dir3_data_header_check(dp, *bpp);
432 if (fa) {
433 __xfs_buf_mark_corrupt(*bpp, fa);
434 xfs_trans_brelse(tp, *bpp);
435 *bpp = NULL;
436 return -EFSCORRUPTED;
437 }
438
439 xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_DATA_BUF);
440 return err;
441}
442
443int
444xfs_dir3_data_readahead(
445 struct xfs_inode *dp,
446 xfs_dablk_t bno,
447 unsigned int flags)
448{
449 return xfs_da_reada_buf(dp, bno, flags, XFS_DATA_FORK,
450 &xfs_dir3_data_reada_buf_ops);
451}
452
453/*
454 * Find the bestfree entry that exactly coincides with unused directory space
455 * or a verifier error because the bestfree data are bad.
456 */
457static xfs_failaddr_t
458xfs_dir2_data_freefind_verify(
459 struct xfs_dir2_data_hdr *hdr,
460 struct xfs_dir2_data_free *bf,
461 struct xfs_dir2_data_unused *dup,
462 struct xfs_dir2_data_free **bf_ent)
463{
464 struct xfs_dir2_data_free *dfp;
465 xfs_dir2_data_aoff_t off;
466 bool matched = false;
467 bool seenzero = false;
468
469 *bf_ent = NULL;
470 off = (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr);
471
472 /*
473 * Validate some consistency in the bestfree table.
474 * Check order, non-overlapping entries, and if we find the
475 * one we're looking for it has to be exact.
476 */
477 for (dfp = &bf[0]; dfp < &bf[XFS_DIR2_DATA_FD_COUNT]; dfp++) {
478 if (!dfp->offset) {
479 if (dfp->length)
480 return __this_address;
481 seenzero = true;
482 continue;
483 }
484 if (seenzero)
485 return __this_address;
486 if (be16_to_cpu(dfp->offset) == off) {
487 matched = true;
488 if (dfp->length != dup->length)
489 return __this_address;
490 } else if (be16_to_cpu(dfp->offset) > off) {
491 if (off + be16_to_cpu(dup->length) >
492 be16_to_cpu(dfp->offset))
493 return __this_address;
494 } else {
495 if (be16_to_cpu(dfp->offset) +
496 be16_to_cpu(dfp->length) > off)
497 return __this_address;
498 }
499 if (!matched &&
500 be16_to_cpu(dfp->length) < be16_to_cpu(dup->length))
501 return __this_address;
502 if (dfp > &bf[0] &&
503 be16_to_cpu(dfp[-1].length) < be16_to_cpu(dfp[0].length))
504 return __this_address;
505 }
506
507 /* Looks ok so far; now try to match up with a bestfree entry. */
508 *bf_ent = xfs_dir2_data_freefind(hdr, bf, dup);
509 return NULL;
510}
511
512/*
513 * Given a data block and an unused entry from that block,
514 * return the bestfree entry if any that corresponds to it.
515 */
516xfs_dir2_data_free_t *
517xfs_dir2_data_freefind(
518 struct xfs_dir2_data_hdr *hdr, /* data block header */
519 struct xfs_dir2_data_free *bf, /* bestfree table pointer */
520 struct xfs_dir2_data_unused *dup) /* unused space */
521{
522 xfs_dir2_data_free_t *dfp; /* bestfree entry */
523 xfs_dir2_data_aoff_t off; /* offset value needed */
524
525 off = (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr);
526
527 /*
528 * If this is smaller than the smallest bestfree entry,
529 * it can't be there since they're sorted.
530 */
531 if (be16_to_cpu(dup->length) <
532 be16_to_cpu(bf[XFS_DIR2_DATA_FD_COUNT - 1].length))
533 return NULL;
534 /*
535 * Look at the three bestfree entries for our guy.
536 */
537 for (dfp = &bf[0]; dfp < &bf[XFS_DIR2_DATA_FD_COUNT]; dfp++) {
538 if (!dfp->offset)
539 return NULL;
540 if (be16_to_cpu(dfp->offset) == off)
541 return dfp;
542 }
543 /*
544 * Didn't find it. This only happens if there are duplicate lengths.
545 */
546 return NULL;
547}
548
549/*
550 * Insert an unused-space entry into the bestfree table.
551 */
552xfs_dir2_data_free_t * /* entry inserted */
553xfs_dir2_data_freeinsert(
554 struct xfs_dir2_data_hdr *hdr, /* data block pointer */
555 struct xfs_dir2_data_free *dfp, /* bestfree table pointer */
556 struct xfs_dir2_data_unused *dup, /* unused space */
557 int *loghead) /* log the data header (out) */
558{
559 xfs_dir2_data_free_t new; /* new bestfree entry */
560
561 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
562 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
563 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
564 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC));
565
566 new.length = dup->length;
567 new.offset = cpu_to_be16((char *)dup - (char *)hdr);
568
569 /*
570 * Insert at position 0, 1, or 2; or not at all.
571 */
572 if (be16_to_cpu(new.length) > be16_to_cpu(dfp[0].length)) {
573 dfp[2] = dfp[1];
574 dfp[1] = dfp[0];
575 dfp[0] = new;
576 *loghead = 1;
577 return &dfp[0];
578 }
579 if (be16_to_cpu(new.length) > be16_to_cpu(dfp[1].length)) {
580 dfp[2] = dfp[1];
581 dfp[1] = new;
582 *loghead = 1;
583 return &dfp[1];
584 }
585 if (be16_to_cpu(new.length) > be16_to_cpu(dfp[2].length)) {
586 dfp[2] = new;
587 *loghead = 1;
588 return &dfp[2];
589 }
590 return NULL;
591}
592
593/*
594 * Remove a bestfree entry from the table.
595 */
596STATIC void
597xfs_dir2_data_freeremove(
598 struct xfs_dir2_data_hdr *hdr, /* data block header */
599 struct xfs_dir2_data_free *bf, /* bestfree table pointer */
600 struct xfs_dir2_data_free *dfp, /* bestfree entry pointer */
601 int *loghead) /* out: log data header */
602{
603
604 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
605 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
606 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
607 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC));
608
609 /*
610 * It's the first entry, slide the next 2 up.
611 */
612 if (dfp == &bf[0]) {
613 bf[0] = bf[1];
614 bf[1] = bf[2];
615 }
616 /*
617 * It's the second entry, slide the 3rd entry up.
618 */
619 else if (dfp == &bf[1])
620 bf[1] = bf[2];
621 /*
622 * Must be the last entry.
623 */
624 else
625 ASSERT(dfp == &bf[2]);
626 /*
627 * Clear the 3rd entry, must be zero now.
628 */
629 bf[2].length = 0;
630 bf[2].offset = 0;
631 *loghead = 1;
632}
633
634/*
635 * Given a data block, reconstruct its bestfree map.
636 */
637void
638xfs_dir2_data_freescan(
639 struct xfs_mount *mp,
640 struct xfs_dir2_data_hdr *hdr,
641 int *loghead)
642{
643 struct xfs_da_geometry *geo = mp->m_dir_geo;
644 struct xfs_dir2_data_free *bf = xfs_dir2_data_bestfree_p(mp, hdr);
645 void *addr = hdr;
646 unsigned int offset = geo->data_entry_offset;
647 unsigned int end;
648
649 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
650 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
651 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
652 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC));
653
654 /*
655 * Start by clearing the table.
656 */
657 memset(bf, 0, sizeof(*bf) * XFS_DIR2_DATA_FD_COUNT);
658 *loghead = 1;
659
660 end = xfs_dir3_data_end_offset(geo, addr);
661 while (offset < end) {
662 struct xfs_dir2_data_unused *dup = addr + offset;
663 struct xfs_dir2_data_entry *dep = addr + offset;
664
665 /*
666 * If it's a free entry, insert it.
667 */
668 if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
669 ASSERT(offset ==
670 be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup)));
671 xfs_dir2_data_freeinsert(hdr, bf, dup, loghead);
672 offset += be16_to_cpu(dup->length);
673 continue;
674 }
675
676 /*
677 * For active entries, check their tags and skip them.
678 */
679 ASSERT(offset ==
680 be16_to_cpu(*xfs_dir2_data_entry_tag_p(mp, dep)));
681 offset += xfs_dir2_data_entsize(mp, dep->namelen);
682 }
683}
684
685/*
686 * Initialize a data block at the given block number in the directory.
687 * Give back the buffer for the created block.
688 */
689int /* error */
690xfs_dir3_data_init(
691 struct xfs_da_args *args, /* directory operation args */
692 xfs_dir2_db_t blkno, /* logical dir block number */
693 struct xfs_buf **bpp) /* output block buffer */
694{
695 struct xfs_trans *tp = args->trans;
696 struct xfs_inode *dp = args->dp;
697 struct xfs_mount *mp = dp->i_mount;
698 struct xfs_da_geometry *geo = args->geo;
699 struct xfs_buf *bp;
700 struct xfs_dir2_data_hdr *hdr;
701 struct xfs_dir2_data_unused *dup;
702 struct xfs_dir2_data_free *bf;
703 int error;
704 int i;
705
706 /*
707 * Get the buffer set up for the block.
708 */
709 error = xfs_da_get_buf(tp, dp, xfs_dir2_db_to_da(args->geo, blkno),
710 &bp, XFS_DATA_FORK);
711 if (error)
712 return error;
713 bp->b_ops = &xfs_dir3_data_buf_ops;
714 xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_DATA_BUF);
715
716 /*
717 * Initialize the header.
718 */
719 hdr = bp->b_addr;
720 if (xfs_has_crc(mp)) {
721 struct xfs_dir3_blk_hdr *hdr3 = bp->b_addr;
722
723 memset(hdr3, 0, sizeof(*hdr3));
724 hdr3->magic = cpu_to_be32(XFS_DIR3_DATA_MAGIC);
725 hdr3->blkno = cpu_to_be64(xfs_buf_daddr(bp));
726 hdr3->owner = cpu_to_be64(dp->i_ino);
727 uuid_copy(&hdr3->uuid, &mp->m_sb.sb_meta_uuid);
728
729 } else
730 hdr->magic = cpu_to_be32(XFS_DIR2_DATA_MAGIC);
731
732 bf = xfs_dir2_data_bestfree_p(mp, hdr);
733 bf[0].offset = cpu_to_be16(geo->data_entry_offset);
734 bf[0].length = cpu_to_be16(geo->blksize - geo->data_entry_offset);
735 for (i = 1; i < XFS_DIR2_DATA_FD_COUNT; i++) {
736 bf[i].length = 0;
737 bf[i].offset = 0;
738 }
739
740 /*
741 * Set up an unused entry for the block's body.
742 */
743 dup = bp->b_addr + geo->data_entry_offset;
744 dup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG);
745 dup->length = bf[0].length;
746 *xfs_dir2_data_unused_tag_p(dup) = cpu_to_be16((char *)dup - (char *)hdr);
747
748 /*
749 * Log it and return it.
750 */
751 xfs_dir2_data_log_header(args, bp);
752 xfs_dir2_data_log_unused(args, bp, dup);
753 *bpp = bp;
754 return 0;
755}
756
757/*
758 * Log an active data entry from the block.
759 */
760void
761xfs_dir2_data_log_entry(
762 struct xfs_da_args *args,
763 struct xfs_buf *bp,
764 xfs_dir2_data_entry_t *dep) /* data entry pointer */
765{
766 struct xfs_mount *mp = bp->b_mount;
767 struct xfs_dir2_data_hdr *hdr = bp->b_addr;
768
769 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
770 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
771 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
772 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC));
773
774 xfs_trans_log_buf(args->trans, bp, (uint)((char *)dep - (char *)hdr),
775 (uint)((char *)(xfs_dir2_data_entry_tag_p(mp, dep) + 1) -
776 (char *)hdr - 1));
777}
778
779/*
780 * Log a data block header.
781 */
782void
783xfs_dir2_data_log_header(
784 struct xfs_da_args *args,
785 struct xfs_buf *bp)
786{
787#ifdef DEBUG
788 struct xfs_dir2_data_hdr *hdr = bp->b_addr;
789
790 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
791 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
792 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
793 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC));
794#endif
795
796 xfs_trans_log_buf(args->trans, bp, 0, args->geo->data_entry_offset - 1);
797}
798
799/*
800 * Log a data unused entry.
801 */
802void
803xfs_dir2_data_log_unused(
804 struct xfs_da_args *args,
805 struct xfs_buf *bp,
806 xfs_dir2_data_unused_t *dup) /* data unused pointer */
807{
808 xfs_dir2_data_hdr_t *hdr = bp->b_addr;
809
810 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
811 hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
812 hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) ||
813 hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC));
814
815 /*
816 * Log the first part of the unused entry.
817 */
818 xfs_trans_log_buf(args->trans, bp, (uint)((char *)dup - (char *)hdr),
819 (uint)((char *)&dup->length + sizeof(dup->length) -
820 1 - (char *)hdr));
821 /*
822 * Log the end (tag) of the unused entry.
823 */
824 xfs_trans_log_buf(args->trans, bp,
825 (uint)((char *)xfs_dir2_data_unused_tag_p(dup) - (char *)hdr),
826 (uint)((char *)xfs_dir2_data_unused_tag_p(dup) - (char *)hdr +
827 sizeof(xfs_dir2_data_off_t) - 1));
828}
829
830/*
831 * Make a byte range in the data block unused.
832 * Its current contents are unimportant.
833 */
834void
835xfs_dir2_data_make_free(
836 struct xfs_da_args *args,
837 struct xfs_buf *bp,
838 xfs_dir2_data_aoff_t offset, /* starting byte offset */
839 xfs_dir2_data_aoff_t len, /* length in bytes */
840 int *needlogp, /* out: log header */
841 int *needscanp) /* out: regen bestfree */
842{
843 xfs_dir2_data_hdr_t *hdr; /* data block pointer */
844 xfs_dir2_data_free_t *dfp; /* bestfree pointer */
845 int needscan; /* need to regen bestfree */
846 xfs_dir2_data_unused_t *newdup; /* new unused entry */
847 xfs_dir2_data_unused_t *postdup; /* unused entry after us */
848 xfs_dir2_data_unused_t *prevdup; /* unused entry before us */
849 unsigned int end;
850 struct xfs_dir2_data_free *bf;
851
852 hdr = bp->b_addr;
853
854 /*
855 * Figure out where the end of the data area is.
856 */
857 end = xfs_dir3_data_end_offset(args->geo, hdr);
858 ASSERT(end != 0);
859
860 /*
861 * If this isn't the start of the block, then back up to
862 * the previous entry and see if it's free.
863 */
864 if (offset > args->geo->data_entry_offset) {
865 __be16 *tagp; /* tag just before us */
866
867 tagp = (__be16 *)((char *)hdr + offset) - 1;
868 prevdup = (xfs_dir2_data_unused_t *)((char *)hdr + be16_to_cpu(*tagp));
869 if (be16_to_cpu(prevdup->freetag) != XFS_DIR2_DATA_FREE_TAG)
870 prevdup = NULL;
871 } else
872 prevdup = NULL;
873 /*
874 * If this isn't the end of the block, see if the entry after
875 * us is free.
876 */
877 if (offset + len < end) {
878 postdup =
879 (xfs_dir2_data_unused_t *)((char *)hdr + offset + len);
880 if (be16_to_cpu(postdup->freetag) != XFS_DIR2_DATA_FREE_TAG)
881 postdup = NULL;
882 } else
883 postdup = NULL;
884 ASSERT(*needscanp == 0);
885 needscan = 0;
886 /*
887 * Previous and following entries are both free,
888 * merge everything into a single free entry.
889 */
890 bf = xfs_dir2_data_bestfree_p(args->dp->i_mount, hdr);
891 if (prevdup && postdup) {
892 xfs_dir2_data_free_t *dfp2; /* another bestfree pointer */
893
894 /*
895 * See if prevdup and/or postdup are in bestfree table.
896 */
897 dfp = xfs_dir2_data_freefind(hdr, bf, prevdup);
898 dfp2 = xfs_dir2_data_freefind(hdr, bf, postdup);
899 /*
900 * We need a rescan unless there are exactly 2 free entries
901 * namely our two. Then we know what's happening, otherwise
902 * since the third bestfree is there, there might be more
903 * entries.
904 */
905 needscan = (bf[2].length != 0);
906 /*
907 * Fix up the new big freespace.
908 */
909 be16_add_cpu(&prevdup->length, len + be16_to_cpu(postdup->length));
910 *xfs_dir2_data_unused_tag_p(prevdup) =
911 cpu_to_be16((char *)prevdup - (char *)hdr);
912 xfs_dir2_data_log_unused(args, bp, prevdup);
913 if (!needscan) {
914 /*
915 * Has to be the case that entries 0 and 1 are
916 * dfp and dfp2 (don't know which is which), and
917 * entry 2 is empty.
918 * Remove entry 1 first then entry 0.
919 */
920 ASSERT(dfp && dfp2);
921 if (dfp == &bf[1]) {
922 dfp = &bf[0];
923 ASSERT(dfp2 == dfp);
924 dfp2 = &bf[1];
925 }
926 xfs_dir2_data_freeremove(hdr, bf, dfp2, needlogp);
927 xfs_dir2_data_freeremove(hdr, bf, dfp, needlogp);
928 /*
929 * Now insert the new entry.
930 */
931 dfp = xfs_dir2_data_freeinsert(hdr, bf, prevdup,
932 needlogp);
933 ASSERT(dfp == &bf[0]);
934 ASSERT(dfp->length == prevdup->length);
935 ASSERT(!dfp[1].length);
936 ASSERT(!dfp[2].length);
937 }
938 }
939 /*
940 * The entry before us is free, merge with it.
941 */
942 else if (prevdup) {
943 dfp = xfs_dir2_data_freefind(hdr, bf, prevdup);
944 be16_add_cpu(&prevdup->length, len);
945 *xfs_dir2_data_unused_tag_p(prevdup) =
946 cpu_to_be16((char *)prevdup - (char *)hdr);
947 xfs_dir2_data_log_unused(args, bp, prevdup);
948 /*
949 * If the previous entry was in the table, the new entry
950 * is longer, so it will be in the table too. Remove
951 * the old one and add the new one.
952 */
953 if (dfp) {
954 xfs_dir2_data_freeremove(hdr, bf, dfp, needlogp);
955 xfs_dir2_data_freeinsert(hdr, bf, prevdup, needlogp);
956 }
957 /*
958 * Otherwise we need a scan if the new entry is big enough.
959 */
960 else {
961 needscan = be16_to_cpu(prevdup->length) >
962 be16_to_cpu(bf[2].length);
963 }
964 }
965 /*
966 * The following entry is free, merge with it.
967 */
968 else if (postdup) {
969 dfp = xfs_dir2_data_freefind(hdr, bf, postdup);
970 newdup = (xfs_dir2_data_unused_t *)((char *)hdr + offset);
971 newdup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG);
972 newdup->length = cpu_to_be16(len + be16_to_cpu(postdup->length));
973 *xfs_dir2_data_unused_tag_p(newdup) =
974 cpu_to_be16((char *)newdup - (char *)hdr);
975 xfs_dir2_data_log_unused(args, bp, newdup);
976 /*
977 * If the following entry was in the table, the new entry
978 * is longer, so it will be in the table too. Remove
979 * the old one and add the new one.
980 */
981 if (dfp) {
982 xfs_dir2_data_freeremove(hdr, bf, dfp, needlogp);
983 xfs_dir2_data_freeinsert(hdr, bf, newdup, needlogp);
984 }
985 /*
986 * Otherwise we need a scan if the new entry is big enough.
987 */
988 else {
989 needscan = be16_to_cpu(newdup->length) >
990 be16_to_cpu(bf[2].length);
991 }
992 }
993 /*
994 * Neither neighbor is free. Make a new entry.
995 */
996 else {
997 newdup = (xfs_dir2_data_unused_t *)((char *)hdr + offset);
998 newdup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG);
999 newdup->length = cpu_to_be16(len);
1000 *xfs_dir2_data_unused_tag_p(newdup) =
1001 cpu_to_be16((char *)newdup - (char *)hdr);
1002 xfs_dir2_data_log_unused(args, bp, newdup);
1003 xfs_dir2_data_freeinsert(hdr, bf, newdup, needlogp);
1004 }
1005 *needscanp = needscan;
1006}
1007
1008/* Check our free data for obvious signs of corruption. */
1009static inline xfs_failaddr_t
1010xfs_dir2_data_check_free(
1011 struct xfs_dir2_data_hdr *hdr,
1012 struct xfs_dir2_data_unused *dup,
1013 xfs_dir2_data_aoff_t offset,
1014 xfs_dir2_data_aoff_t len)
1015{
1016 if (hdr->magic != cpu_to_be32(XFS_DIR2_DATA_MAGIC) &&
1017 hdr->magic != cpu_to_be32(XFS_DIR3_DATA_MAGIC) &&
1018 hdr->magic != cpu_to_be32(XFS_DIR2_BLOCK_MAGIC) &&
1019 hdr->magic != cpu_to_be32(XFS_DIR3_BLOCK_MAGIC))
1020 return __this_address;
1021 if (be16_to_cpu(dup->freetag) != XFS_DIR2_DATA_FREE_TAG)
1022 return __this_address;
1023 if (offset < (char *)dup - (char *)hdr)
1024 return __this_address;
1025 if (offset + len > (char *)dup + be16_to_cpu(dup->length) - (char *)hdr)
1026 return __this_address;
1027 if ((char *)dup - (char *)hdr !=
1028 be16_to_cpu(*xfs_dir2_data_unused_tag_p(dup)))
1029 return __this_address;
1030 return NULL;
1031}
1032
1033/* Sanity-check a new bestfree entry. */
1034static inline xfs_failaddr_t
1035xfs_dir2_data_check_new_free(
1036 struct xfs_dir2_data_hdr *hdr,
1037 struct xfs_dir2_data_free *dfp,
1038 struct xfs_dir2_data_unused *newdup)
1039{
1040 if (dfp == NULL)
1041 return __this_address;
1042 if (dfp->length != newdup->length)
1043 return __this_address;
1044 if (be16_to_cpu(dfp->offset) != (char *)newdup - (char *)hdr)
1045 return __this_address;
1046 return NULL;
1047}
1048
1049/*
1050 * Take a byte range out of an existing unused space and make it un-free.
1051 */
1052int
1053xfs_dir2_data_use_free(
1054 struct xfs_da_args *args,
1055 struct xfs_buf *bp,
1056 xfs_dir2_data_unused_t *dup, /* unused entry */
1057 xfs_dir2_data_aoff_t offset, /* starting offset to use */
1058 xfs_dir2_data_aoff_t len, /* length to use */
1059 int *needlogp, /* out: need to log header */
1060 int *needscanp) /* out: need regen bestfree */
1061{
1062 xfs_dir2_data_hdr_t *hdr; /* data block header */
1063 xfs_dir2_data_free_t *dfp; /* bestfree pointer */
1064 xfs_dir2_data_unused_t *newdup; /* new unused entry */
1065 xfs_dir2_data_unused_t *newdup2; /* another new unused entry */
1066 struct xfs_dir2_data_free *bf;
1067 xfs_failaddr_t fa;
1068 int matchback; /* matches end of freespace */
1069 int matchfront; /* matches start of freespace */
1070 int needscan; /* need to regen bestfree */
1071 int oldlen; /* old unused entry's length */
1072
1073 hdr = bp->b_addr;
1074 fa = xfs_dir2_data_check_free(hdr, dup, offset, len);
1075 if (fa)
1076 goto corrupt;
1077 /*
1078 * Look up the entry in the bestfree table.
1079 */
1080 oldlen = be16_to_cpu(dup->length);
1081 bf = xfs_dir2_data_bestfree_p(args->dp->i_mount, hdr);
1082 dfp = xfs_dir2_data_freefind(hdr, bf, dup);
1083 ASSERT(dfp || oldlen <= be16_to_cpu(bf[2].length));
1084 /*
1085 * Check for alignment with front and back of the entry.
1086 */
1087 matchfront = (char *)dup - (char *)hdr == offset;
1088 matchback = (char *)dup + oldlen - (char *)hdr == offset + len;
1089 ASSERT(*needscanp == 0);
1090 needscan = 0;
1091 /*
1092 * If we matched it exactly we just need to get rid of it from
1093 * the bestfree table.
1094 */
1095 if (matchfront && matchback) {
1096 if (dfp) {
1097 needscan = (bf[2].offset != 0);
1098 if (!needscan)
1099 xfs_dir2_data_freeremove(hdr, bf, dfp,
1100 needlogp);
1101 }
1102 }
1103 /*
1104 * We match the first part of the entry.
1105 * Make a new entry with the remaining freespace.
1106 */
1107 else if (matchfront) {
1108 newdup = (xfs_dir2_data_unused_t *)((char *)hdr + offset + len);
1109 newdup->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG);
1110 newdup->length = cpu_to_be16(oldlen - len);
1111 *xfs_dir2_data_unused_tag_p(newdup) =
1112 cpu_to_be16((char *)newdup - (char *)hdr);
1113 xfs_dir2_data_log_unused(args, bp, newdup);
1114 /*
1115 * If it was in the table, remove it and add the new one.
1116 */
1117 if (dfp) {
1118 xfs_dir2_data_freeremove(hdr, bf, dfp, needlogp);
1119 dfp = xfs_dir2_data_freeinsert(hdr, bf, newdup,
1120 needlogp);
1121 fa = xfs_dir2_data_check_new_free(hdr, dfp, newdup);
1122 if (fa)
1123 goto corrupt;
1124 /*
1125 * If we got inserted at the last slot,
1126 * that means we don't know if there was a better
1127 * choice for the last slot, or not. Rescan.
1128 */
1129 needscan = dfp == &bf[2];
1130 }
1131 }
1132 /*
1133 * We match the last part of the entry.
1134 * Trim the allocated space off the tail of the entry.
1135 */
1136 else if (matchback) {
1137 newdup = dup;
1138 newdup->length = cpu_to_be16(((char *)hdr + offset) - (char *)newdup);
1139 *xfs_dir2_data_unused_tag_p(newdup) =
1140 cpu_to_be16((char *)newdup - (char *)hdr);
1141 xfs_dir2_data_log_unused(args, bp, newdup);
1142 /*
1143 * If it was in the table, remove it and add the new one.
1144 */
1145 if (dfp) {
1146 xfs_dir2_data_freeremove(hdr, bf, dfp, needlogp);
1147 dfp = xfs_dir2_data_freeinsert(hdr, bf, newdup,
1148 needlogp);
1149 fa = xfs_dir2_data_check_new_free(hdr, dfp, newdup);
1150 if (fa)
1151 goto corrupt;
1152 /*
1153 * If we got inserted at the last slot,
1154 * that means we don't know if there was a better
1155 * choice for the last slot, or not. Rescan.
1156 */
1157 needscan = dfp == &bf[2];
1158 }
1159 }
1160 /*
1161 * Poking out the middle of an entry.
1162 * Make two new entries.
1163 */
1164 else {
1165 newdup = dup;
1166 newdup->length = cpu_to_be16(((char *)hdr + offset) - (char *)newdup);
1167 *xfs_dir2_data_unused_tag_p(newdup) =
1168 cpu_to_be16((char *)newdup - (char *)hdr);
1169 xfs_dir2_data_log_unused(args, bp, newdup);
1170 newdup2 = (xfs_dir2_data_unused_t *)((char *)hdr + offset + len);
1171 newdup2->freetag = cpu_to_be16(XFS_DIR2_DATA_FREE_TAG);
1172 newdup2->length = cpu_to_be16(oldlen - len - be16_to_cpu(newdup->length));
1173 *xfs_dir2_data_unused_tag_p(newdup2) =
1174 cpu_to_be16((char *)newdup2 - (char *)hdr);
1175 xfs_dir2_data_log_unused(args, bp, newdup2);
1176 /*
1177 * If the old entry was in the table, we need to scan
1178 * if the 3rd entry was valid, since these entries
1179 * are smaller than the old one.
1180 * If we don't need to scan that means there were 1 or 2
1181 * entries in the table, and removing the old and adding
1182 * the 2 new will work.
1183 */
1184 if (dfp) {
1185 needscan = (bf[2].length != 0);
1186 if (!needscan) {
1187 xfs_dir2_data_freeremove(hdr, bf, dfp,
1188 needlogp);
1189 xfs_dir2_data_freeinsert(hdr, bf, newdup,
1190 needlogp);
1191 xfs_dir2_data_freeinsert(hdr, bf, newdup2,
1192 needlogp);
1193 }
1194 }
1195 }
1196 *needscanp = needscan;
1197 return 0;
1198corrupt:
1199 xfs_corruption_error(__func__, XFS_ERRLEVEL_LOW, args->dp->i_mount,
1200 hdr, sizeof(*hdr), __FILE__, __LINE__, fa);
1201 return -EFSCORRUPTED;
1202}
1203
1204/* Find the end of the entry data in a data/block format dir block. */
1205unsigned int
1206xfs_dir3_data_end_offset(
1207 struct xfs_da_geometry *geo,
1208 struct xfs_dir2_data_hdr *hdr)
1209{
1210 void *p;
1211
1212 switch (hdr->magic) {
1213 case cpu_to_be32(XFS_DIR3_BLOCK_MAGIC):
1214 case cpu_to_be32(XFS_DIR2_BLOCK_MAGIC):
1215 p = xfs_dir2_block_leaf_p(xfs_dir2_block_tail_p(geo, hdr));
1216 return p - (void *)hdr;
1217 case cpu_to_be32(XFS_DIR3_DATA_MAGIC):
1218 case cpu_to_be32(XFS_DIR2_DATA_MAGIC):
1219 return geo->blksize;
1220 default:
1221 return 0;
1222 }
1223}