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Prevent freeing uninitialized pointer in compat_do_readv_writev
[linux-2.6.git] / fs / xfs / xfs_dir2_leaf.c
blob504be8640e918250d5ea58a6df3d64c223655187
1 /*
2 * Copyright (c) 2000-2003,2005 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_types.h"
21 #include "xfs_bit.h"
22 #include "xfs_log.h"
23 #include "xfs_inum.h"
24 #include "xfs_trans.h"
25 #include "xfs_sb.h"
26 #include "xfs_ag.h"
27 #include "xfs_dir2.h"
28 #include "xfs_mount.h"
29 #include "xfs_da_btree.h"
30 #include "xfs_bmap_btree.h"
31 #include "xfs_dir2_sf.h"
32 #include "xfs_dinode.h"
33 #include "xfs_inode.h"
34 #include "xfs_bmap.h"
35 #include "xfs_dir2_data.h"
36 #include "xfs_dir2_leaf.h"
37 #include "xfs_dir2_block.h"
38 #include "xfs_dir2_node.h"
39 #include "xfs_error.h"
40 #include "xfs_trace.h"
41
42 /*
43 * Local function declarations.
44 */
45 #ifdef DEBUG
46 static void xfs_dir2_leaf_check(xfs_inode_t *dp, xfs_dabuf_t *bp);
47 #else
48 #define xfs_dir2_leaf_check(dp, bp)
49 #endif
50 static int xfs_dir2_leaf_lookup_int(xfs_da_args_t *args, xfs_dabuf_t **lbpp,
51 int *indexp, xfs_dabuf_t **dbpp);
52 static void xfs_dir2_leaf_log_bests(struct xfs_trans *tp, struct xfs_dabuf *bp,
53 int first, int last);
54 static void xfs_dir2_leaf_log_tail(struct xfs_trans *tp, struct xfs_dabuf *bp);
55
56
57 /*
58 * Convert a block form directory to a leaf form directory.
59 */
60 int /* error */
61 xfs_dir2_block_to_leaf(
62 xfs_da_args_t *args, /* operation arguments */
63 xfs_dabuf_t *dbp) /* input block's buffer */
64 {
65 __be16 *bestsp; /* leaf's bestsp entries */
66 xfs_dablk_t blkno; /* leaf block's bno */
67 xfs_dir2_block_t *block; /* block structure */
68 xfs_dir2_leaf_entry_t *blp; /* block's leaf entries */
69 xfs_dir2_block_tail_t *btp; /* block's tail */
70 xfs_inode_t *dp; /* incore directory inode */
71 int error; /* error return code */
72 xfs_dabuf_t *lbp; /* leaf block's buffer */
73 xfs_dir2_db_t ldb; /* leaf block's bno */
74 xfs_dir2_leaf_t *leaf; /* leaf structure */
75 xfs_dir2_leaf_tail_t *ltp; /* leaf's tail */
76 xfs_mount_t *mp; /* filesystem mount point */
77 int needlog; /* need to log block header */
78 int needscan; /* need to rescan bestfree */
79 xfs_trans_t *tp; /* transaction pointer */
80
81 trace_xfs_dir2_block_to_leaf(args);
82
83 dp = args->dp;
84 mp = dp->i_mount;
85 tp = args->trans;
86 /*
87 * Add the leaf block to the inode.
88 * This interface will only put blocks in the leaf/node range.
89 * Since that's empty now, we'll get the root (block 0 in range).
90 */
91 if ((error = xfs_da_grow_inode(args, &blkno))) {
92 return error;
93 }
94 ldb = xfs_dir2_da_to_db(mp, blkno);
95 ASSERT(ldb == XFS_DIR2_LEAF_FIRSTDB(mp));
96 /*
97 * Initialize the leaf block, get a buffer for it.
98 */
99 if ((error = xfs_dir2_leaf_init(args, ldb, &lbp, XFS_DIR2_LEAF1_MAGIC))) {
100 return error;
101 }
102 ASSERT(lbp != NULL);
103 leaf = lbp->data;
104 block = dbp->data;
105 xfs_dir2_data_check(dp, dbp);
106 btp = xfs_dir2_block_tail_p(mp, block);
107 blp = xfs_dir2_block_leaf_p(btp);
108 /*
109 * Set the counts in the leaf header.
110 */
111 leaf->hdr.count = cpu_to_be16(be32_to_cpu(btp->count));
112 leaf->hdr.stale = cpu_to_be16(be32_to_cpu(btp->stale));
113 /*
114 * Could compact these but I think we always do the conversion
115 * after squeezing out stale entries.
116 */
117 memcpy(leaf->ents, blp, be32_to_cpu(btp->count) * sizeof(xfs_dir2_leaf_entry_t));
118 xfs_dir2_leaf_log_ents(tp, lbp, 0, be16_to_cpu(leaf->hdr.count) - 1);
119 needscan = 0;
120 needlog = 1;
121 /*
122 * Make the space formerly occupied by the leaf entries and block
123 * tail be free.
124 */
125 xfs_dir2_data_make_free(tp, dbp,
126 (xfs_dir2_data_aoff_t)((char *)blp - (char *)block),
127 (xfs_dir2_data_aoff_t)((char *)block + mp->m_dirblksize -
128 (char *)blp),
129 &needlog, &needscan);
130 /*
131 * Fix up the block header, make it a data block.
132 */
133 block->hdr.magic = cpu_to_be32(XFS_DIR2_DATA_MAGIC);
134 if (needscan)
135 xfs_dir2_data_freescan(mp, (xfs_dir2_data_t *)block, &needlog);
136 /*
137 * Set up leaf tail and bests table.
138 */
139 ltp = xfs_dir2_leaf_tail_p(mp, leaf);
140 ltp->bestcount = cpu_to_be32(1);
141 bestsp = xfs_dir2_leaf_bests_p(ltp);
142 bestsp[0] = block->hdr.bestfree[0].length;
143 /*
144 * Log the data header and leaf bests table.
145 */
146 if (needlog)
147 xfs_dir2_data_log_header(tp, dbp);
148 xfs_dir2_leaf_check(dp, lbp);
149 xfs_dir2_data_check(dp, dbp);
150 xfs_dir2_leaf_log_bests(tp, lbp, 0, 0);
151 xfs_da_buf_done(lbp);
152 return 0;
153 }
154
155 /*
156 * Add an entry to a leaf form directory.
157 */
158 int /* error */
159 xfs_dir2_leaf_addname(
160 xfs_da_args_t *args) /* operation arguments */
161 {
162 __be16 *bestsp; /* freespace table in leaf */
163 int compact; /* need to compact leaves */
164 xfs_dir2_data_t *data; /* data block structure */
165 xfs_dabuf_t *dbp; /* data block buffer */
166 xfs_dir2_data_entry_t *dep; /* data block entry */
167 xfs_inode_t *dp; /* incore directory inode */
168 xfs_dir2_data_unused_t *dup; /* data unused entry */
169 int error; /* error return value */
170 int grown; /* allocated new data block */
171 int highstale; /* index of next stale leaf */
172 int i; /* temporary, index */
173 int index; /* leaf table position */
174 xfs_dabuf_t *lbp; /* leaf's buffer */
175 xfs_dir2_leaf_t *leaf; /* leaf structure */
176 int length; /* length of new entry */
177 xfs_dir2_leaf_entry_t *lep; /* leaf entry table pointer */
178 int lfloglow; /* low leaf logging index */
179 int lfloghigh; /* high leaf logging index */
180 int lowstale; /* index of prev stale leaf */
181 xfs_dir2_leaf_tail_t *ltp; /* leaf tail pointer */
182 xfs_mount_t *mp; /* filesystem mount point */
183 int needbytes; /* leaf block bytes needed */
184 int needlog; /* need to log data header */
185 int needscan; /* need to rescan data free */
186 __be16 *tagp; /* end of data entry */
187 xfs_trans_t *tp; /* transaction pointer */
188 xfs_dir2_db_t use_block; /* data block number */
189
190 trace_xfs_dir2_leaf_addname(args);
191
192 dp = args->dp;
193 tp = args->trans;
194 mp = dp->i_mount;
195 /*
196 * Read the leaf block.
197 */
198 error = xfs_da_read_buf(tp, dp, mp->m_dirleafblk, -1, &lbp,
199 XFS_DATA_FORK);
200 if (error) {
201 return error;
202 }
203 ASSERT(lbp != NULL);
204 /*
205 * Look up the entry by hash value and name.
206 * We know it's not there, our caller has already done a lookup.
207 * So the index is of the entry to insert in front of.
208 * But if there are dup hash values the index is of the first of those.
209 */
210 index = xfs_dir2_leaf_search_hash(args, lbp);
211 leaf = lbp->data;
212 ltp = xfs_dir2_leaf_tail_p(mp, leaf);
213 bestsp = xfs_dir2_leaf_bests_p(ltp);
214 length = xfs_dir2_data_entsize(args->namelen);
215 /*
216 * See if there are any entries with the same hash value
217 * and space in their block for the new entry.
218 * This is good because it puts multiple same-hash value entries
219 * in a data block, improving the lookup of those entries.
220 */
221 for (use_block = -1, lep = &leaf->ents[index];
222 index < be16_to_cpu(leaf->hdr.count) && be32_to_cpu(lep->hashval) == args->hashval;
223 index++, lep++) {
224 if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
225 continue;
226 i = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
227 ASSERT(i < be32_to_cpu(ltp->bestcount));
228 ASSERT(be16_to_cpu(bestsp[i]) != NULLDATAOFF);
229 if (be16_to_cpu(bestsp[i]) >= length) {
230 use_block = i;
231 break;
232 }
233 }
234 /*
235 * Didn't find a block yet, linear search all the data blocks.
236 */
237 if (use_block == -1) {
238 for (i = 0; i < be32_to_cpu(ltp->bestcount); i++) {
239 /*
240 * Remember a block we see that's missing.
241 */
242 if (be16_to_cpu(bestsp[i]) == NULLDATAOFF && use_block == -1)
243 use_block = i;
244 else if (be16_to_cpu(bestsp[i]) >= length) {
245 use_block = i;
246 break;
247 }
248 }
249 }
250 /*
251 * How many bytes do we need in the leaf block?
252 */
253 needbytes =
254 (leaf->hdr.stale ? 0 : (uint)sizeof(leaf->ents[0])) +
255 (use_block != -1 ? 0 : (uint)sizeof(leaf->bests[0]));
256 /*
257 * Now kill use_block if it refers to a missing block, so we
258 * can use it as an indication of allocation needed.
259 */
260 if (use_block != -1 && be16_to_cpu(bestsp[use_block]) == NULLDATAOFF)
261 use_block = -1;
262 /*
263 * If we don't have enough free bytes but we can make enough
264 * by compacting out stale entries, we'll do that.
265 */
266 if ((char *)bestsp - (char *)&leaf->ents[be16_to_cpu(leaf->hdr.count)] <
267 needbytes && be16_to_cpu(leaf->hdr.stale) > 1) {
268 compact = 1;
269 }
270 /*
271 * Otherwise if we don't have enough free bytes we need to
272 * convert to node form.
273 */
274 else if ((char *)bestsp - (char *)&leaf->ents[be16_to_cpu(
275 leaf->hdr.count)] < needbytes) {
276 /*
277 * Just checking or no space reservation, give up.
278 */
279 if ((args->op_flags & XFS_DA_OP_JUSTCHECK) ||
280 args->total == 0) {
281 xfs_da_brelse(tp, lbp);
282 return XFS_ERROR(ENOSPC);
283 }
284 /*
285 * Convert to node form.
286 */
287 error = xfs_dir2_leaf_to_node(args, lbp);
288 xfs_da_buf_done(lbp);
289 if (error)
290 return error;
291 /*
292 * Then add the new entry.
293 */
294 return xfs_dir2_node_addname(args);
295 }
296 /*
297 * Otherwise it will fit without compaction.
298 */
299 else
300 compact = 0;
301 /*
302 * If just checking, then it will fit unless we needed to allocate
303 * a new data block.
304 */
305 if (args->op_flags & XFS_DA_OP_JUSTCHECK) {
306 xfs_da_brelse(tp, lbp);
307 return use_block == -1 ? XFS_ERROR(ENOSPC) : 0;
308 }
309 /*
310 * If no allocations are allowed, return now before we've
311 * changed anything.
312 */
313 if (args->total == 0 && use_block == -1) {
314 xfs_da_brelse(tp, lbp);
315 return XFS_ERROR(ENOSPC);
316 }
317 /*
318 * Need to compact the leaf entries, removing stale ones.
319 * Leave one stale entry behind - the one closest to our
320 * insertion index - and we'll shift that one to our insertion
321 * point later.
322 */
323 if (compact) {
324 xfs_dir2_leaf_compact_x1(lbp, &index, &lowstale, &highstale,
325 &lfloglow, &lfloghigh);
326 }
327 /*
328 * There are stale entries, so we'll need log-low and log-high
329 * impossibly bad values later.
330 */
331 else if (be16_to_cpu(leaf->hdr.stale)) {
332 lfloglow = be16_to_cpu(leaf->hdr.count);
333 lfloghigh = -1;
334 }
335 /*
336 * If there was no data block space found, we need to allocate
337 * a new one.
338 */
339 if (use_block == -1) {
340 /*
341 * Add the new data block.
342 */
343 if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_DATA_SPACE,
344 &use_block))) {
345 xfs_da_brelse(tp, lbp);
346 return error;
347 }
348 /*
349 * Initialize the block.
350 */
351 if ((error = xfs_dir2_data_init(args, use_block, &dbp))) {
352 xfs_da_brelse(tp, lbp);
353 return error;
354 }
355 /*
356 * If we're adding a new data block on the end we need to
357 * extend the bests table. Copy it up one entry.
358 */
359 if (use_block >= be32_to_cpu(ltp->bestcount)) {
360 bestsp--;
361 memmove(&bestsp[0], &bestsp[1],
362 be32_to_cpu(ltp->bestcount) * sizeof(bestsp[0]));
363 be32_add_cpu(&ltp->bestcount, 1);
364 xfs_dir2_leaf_log_tail(tp, lbp);
365 xfs_dir2_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
366 }
367 /*
368 * If we're filling in a previously empty block just log it.
369 */
370 else
371 xfs_dir2_leaf_log_bests(tp, lbp, use_block, use_block);
372 data = dbp->data;
373 bestsp[use_block] = data->hdr.bestfree[0].length;
374 grown = 1;
375 }
376 /*
377 * Already had space in some data block.
378 * Just read that one in.
379 */
380 else {
381 if ((error =
382 xfs_da_read_buf(tp, dp, xfs_dir2_db_to_da(mp, use_block),
383 -1, &dbp, XFS_DATA_FORK))) {
384 xfs_da_brelse(tp, lbp);
385 return error;
386 }
387 data = dbp->data;
388 grown = 0;
389 }
390 xfs_dir2_data_check(dp, dbp);
391 /*
392 * Point to the biggest freespace in our data block.
393 */
394 dup = (xfs_dir2_data_unused_t *)
395 ((char *)data + be16_to_cpu(data->hdr.bestfree[0].offset));
396 ASSERT(be16_to_cpu(dup->length) >= length);
397 needscan = needlog = 0;
398 /*
399 * Mark the initial part of our freespace in use for the new entry.
400 */
401 xfs_dir2_data_use_free(tp, dbp, dup,
402 (xfs_dir2_data_aoff_t)((char *)dup - (char *)data), length,
403 &needlog, &needscan);
404 /*
405 * Initialize our new entry (at last).
406 */
407 dep = (xfs_dir2_data_entry_t *)dup;
408 dep->inumber = cpu_to_be64(args->inumber);
409 dep->namelen = args->namelen;
410 memcpy(dep->name, args->name, dep->namelen);
411 tagp = xfs_dir2_data_entry_tag_p(dep);
412 *tagp = cpu_to_be16((char *)dep - (char *)data);
413 /*
414 * Need to scan fix up the bestfree table.
415 */
416 if (needscan)
417 xfs_dir2_data_freescan(mp, data, &needlog);
418 /*
419 * Need to log the data block's header.
420 */
421 if (needlog)
422 xfs_dir2_data_log_header(tp, dbp);
423 xfs_dir2_data_log_entry(tp, dbp, dep);
424 /*
425 * If the bests table needs to be changed, do it.
426 * Log the change unless we've already done that.
427 */
428 if (be16_to_cpu(bestsp[use_block]) != be16_to_cpu(data->hdr.bestfree[0].length)) {
429 bestsp[use_block] = data->hdr.bestfree[0].length;
430 if (!grown)
431 xfs_dir2_leaf_log_bests(tp, lbp, use_block, use_block);
432 }
433 /*
434 * Now we need to make room to insert the leaf entry.
435 * If there are no stale entries, we just insert a hole at index.
436 */
437 if (!leaf->hdr.stale) {
438 /*
439 * lep is still good as the index leaf entry.
440 */
441 if (index < be16_to_cpu(leaf->hdr.count))
442 memmove(lep + 1, lep,
443 (be16_to_cpu(leaf->hdr.count) - index) * sizeof(*lep));
444 /*
445 * Record low and high logging indices for the leaf.
446 */
447 lfloglow = index;
448 lfloghigh = be16_to_cpu(leaf->hdr.count);
449 be16_add_cpu(&leaf->hdr.count, 1);
450 }
451 /*
452 * There are stale entries.
453 * We will use one of them for the new entry.
454 * It's probably not at the right location, so we'll have to
455 * shift some up or down first.
456 */
457 else {
458 /*
459 * If we didn't compact before, we need to find the nearest
460 * stale entries before and after our insertion point.
461 */
462 if (compact == 0) {
463 /*
464 * Find the first stale entry before the insertion
465 * point, if any.
466 */
467 for (lowstale = index - 1;
468 lowstale >= 0 &&
469 be32_to_cpu(leaf->ents[lowstale].address) !=
470 XFS_DIR2_NULL_DATAPTR;
471 lowstale--)
472 continue;
473 /*
474 * Find the next stale entry at or after the insertion
475 * point, if any. Stop if we go so far that the
476 * lowstale entry would be better.
477 */
478 for (highstale = index;
479 highstale < be16_to_cpu(leaf->hdr.count) &&
480 be32_to_cpu(leaf->ents[highstale].address) !=
481 XFS_DIR2_NULL_DATAPTR &&
482 (lowstale < 0 ||
483 index - lowstale - 1 >= highstale - index);
484 highstale++)
485 continue;
486 }
487 /*
488 * If the low one is better, use it.
489 */
490 if (lowstale >= 0 &&
491 (highstale == be16_to_cpu(leaf->hdr.count) ||
492 index - lowstale - 1 < highstale - index)) {
493 ASSERT(index - lowstale - 1 >= 0);
494 ASSERT(be32_to_cpu(leaf->ents[lowstale].address) ==
495 XFS_DIR2_NULL_DATAPTR);
496 /*
497 * Copy entries up to cover the stale entry
498 * and make room for the new entry.
499 */
500 if (index - lowstale - 1 > 0)
501 memmove(&leaf->ents[lowstale],
502 &leaf->ents[lowstale + 1],
503 (index - lowstale - 1) * sizeof(*lep));
504 lep = &leaf->ents[index - 1];
505 lfloglow = MIN(lowstale, lfloglow);
506 lfloghigh = MAX(index - 1, lfloghigh);
507 }
508 /*
509 * The high one is better, so use that one.
510 */
511 else {
512 ASSERT(highstale - index >= 0);
513 ASSERT(be32_to_cpu(leaf->ents[highstale].address) ==
514 XFS_DIR2_NULL_DATAPTR);
515 /*
516 * Copy entries down to cover the stale entry
517 * and make room for the new entry.
518 */
519 if (highstale - index > 0)
520 memmove(&leaf->ents[index + 1],
521 &leaf->ents[index],
522 (highstale - index) * sizeof(*lep));
523 lep = &leaf->ents[index];
524 lfloglow = MIN(index, lfloglow);
525 lfloghigh = MAX(highstale, lfloghigh);
526 }
527 be16_add_cpu(&leaf->hdr.stale, -1);
528 }
529 /*
530 * Fill in the new leaf entry.
531 */
532 lep->hashval = cpu_to_be32(args->hashval);
533 lep->address = cpu_to_be32(xfs_dir2_db_off_to_dataptr(mp, use_block,
534 be16_to_cpu(*tagp)));
535 /*
536 * Log the leaf fields and give up the buffers.
537 */
538 xfs_dir2_leaf_log_header(tp, lbp);
539 xfs_dir2_leaf_log_ents(tp, lbp, lfloglow, lfloghigh);
540 xfs_dir2_leaf_check(dp, lbp);
541 xfs_da_buf_done(lbp);
542 xfs_dir2_data_check(dp, dbp);
543 xfs_da_buf_done(dbp);
544 return 0;
545 }
546
547 #ifdef DEBUG
548 /*
549 * Check the internal consistency of a leaf1 block.
550 * Pop an assert if something is wrong.
551 */
552 STATIC void
553 xfs_dir2_leaf_check(
554 xfs_inode_t *dp, /* incore directory inode */
555 xfs_dabuf_t *bp) /* leaf's buffer */
556 {
557 int i; /* leaf index */
558 xfs_dir2_leaf_t *leaf; /* leaf structure */
559 xfs_dir2_leaf_tail_t *ltp; /* leaf tail pointer */
560 xfs_mount_t *mp; /* filesystem mount point */
561 int stale; /* count of stale leaves */
562
563 leaf = bp->data;
564 mp = dp->i_mount;
565 ASSERT(be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAF1_MAGIC);
566 /*
567 * This value is not restrictive enough.
568 * Should factor in the size of the bests table as well.
569 * We can deduce a value for that from di_size.
570 */
571 ASSERT(be16_to_cpu(leaf->hdr.count) <= xfs_dir2_max_leaf_ents(mp));
572 ltp = xfs_dir2_leaf_tail_p(mp, leaf);
573 /*
574 * Leaves and bests don't overlap.
575 */
576 ASSERT((char *)&leaf->ents[be16_to_cpu(leaf->hdr.count)] <=
577 (char *)xfs_dir2_leaf_bests_p(ltp));
578 /*
579 * Check hash value order, count stale entries.
580 */
581 for (i = stale = 0; i < be16_to_cpu(leaf->hdr.count); i++) {
582 if (i + 1 < be16_to_cpu(leaf->hdr.count))
583 ASSERT(be32_to_cpu(leaf->ents[i].hashval) <=
584 be32_to_cpu(leaf->ents[i + 1].hashval));
585 if (be32_to_cpu(leaf->ents[i].address) == XFS_DIR2_NULL_DATAPTR)
586 stale++;
587 }
588 ASSERT(be16_to_cpu(leaf->hdr.stale) == stale);
589 }
590 #endif /* DEBUG */
591
592 /*
593 * Compact out any stale entries in the leaf.
594 * Log the header and changed leaf entries, if any.
595 */
596 void
597 xfs_dir2_leaf_compact(
598 xfs_da_args_t *args, /* operation arguments */
599 xfs_dabuf_t *bp) /* leaf buffer */
600 {
601 int from; /* source leaf index */
602 xfs_dir2_leaf_t *leaf; /* leaf structure */
603 int loglow; /* first leaf entry to log */
604 int to; /* target leaf index */
605
606 leaf = bp->data;
607 if (!leaf->hdr.stale) {
608 return;
609 }
610 /*
611 * Compress out the stale entries in place.
612 */
613 for (from = to = 0, loglow = -1; from < be16_to_cpu(leaf->hdr.count); from++) {
614 if (be32_to_cpu(leaf->ents[from].address) == XFS_DIR2_NULL_DATAPTR)
615 continue;
616 /*
617 * Only actually copy the entries that are different.
618 */
619 if (from > to) {
620 if (loglow == -1)
621 loglow = to;
622 leaf->ents[to] = leaf->ents[from];
623 }
624 to++;
625 }
626 /*
627 * Update and log the header, log the leaf entries.
628 */
629 ASSERT(be16_to_cpu(leaf->hdr.stale) == from - to);
630 be16_add_cpu(&leaf->hdr.count, -(be16_to_cpu(leaf->hdr.stale)));
631 leaf->hdr.stale = 0;
632 xfs_dir2_leaf_log_header(args->trans, bp);
633 if (loglow != -1)
634 xfs_dir2_leaf_log_ents(args->trans, bp, loglow, to - 1);
635 }
636
637 /*
638 * Compact the leaf entries, removing stale ones.
639 * Leave one stale entry behind - the one closest to our
640 * insertion index - and the caller will shift that one to our insertion
641 * point later.
642 * Return new insertion index, where the remaining stale entry is,
643 * and leaf logging indices.
644 */
645 void
646 xfs_dir2_leaf_compact_x1(
647 xfs_dabuf_t *bp, /* leaf buffer */
648 int *indexp, /* insertion index */
649 int *lowstalep, /* out: stale entry before us */
650 int *highstalep, /* out: stale entry after us */
651 int *lowlogp, /* out: low log index */
652 int *highlogp) /* out: high log index */
653 {
654 int from; /* source copy index */
655 int highstale; /* stale entry at/after index */
656 int index; /* insertion index */
657 int keepstale; /* source index of kept stale */
658 xfs_dir2_leaf_t *leaf; /* leaf structure */
659 int lowstale; /* stale entry before index */
660 int newindex=0; /* new insertion index */
661 int to; /* destination copy index */
662
663 leaf = bp->data;
664 ASSERT(be16_to_cpu(leaf->hdr.stale) > 1);
665 index = *indexp;
666 /*
667 * Find the first stale entry before our index, if any.
668 */
669 for (lowstale = index - 1;
670 lowstale >= 0 &&
671 be32_to_cpu(leaf->ents[lowstale].address) != XFS_DIR2_NULL_DATAPTR;
672 lowstale--)
673 continue;
674 /*
675 * Find the first stale entry at or after our index, if any.
676 * Stop if the answer would be worse than lowstale.
677 */
678 for (highstale = index;
679 highstale < be16_to_cpu(leaf->hdr.count) &&
680 be32_to_cpu(leaf->ents[highstale].address) != XFS_DIR2_NULL_DATAPTR &&
681 (lowstale < 0 || index - lowstale > highstale - index);
682 highstale++)
683 continue;
684 /*
685 * Pick the better of lowstale and highstale.
686 */
687 if (lowstale >= 0 &&
688 (highstale == be16_to_cpu(leaf->hdr.count) ||
689 index - lowstale <= highstale - index))
690 keepstale = lowstale;
691 else
692 keepstale = highstale;
693 /*
694 * Copy the entries in place, removing all the stale entries
695 * except keepstale.
696 */
697 for (from = to = 0; from < be16_to_cpu(leaf->hdr.count); from++) {
698 /*
699 * Notice the new value of index.
700 */
701 if (index == from)
702 newindex = to;
703 if (from != keepstale &&
704 be32_to_cpu(leaf->ents[from].address) == XFS_DIR2_NULL_DATAPTR) {
705 if (from == to)
706 *lowlogp = to;
707 continue;
708 }
709 /*
710 * Record the new keepstale value for the insertion.
711 */
712 if (from == keepstale)
713 lowstale = highstale = to;
714 /*
715 * Copy only the entries that have moved.
716 */
717 if (from > to)
718 leaf->ents[to] = leaf->ents[from];
719 to++;
720 }
721 ASSERT(from > to);
722 /*
723 * If the insertion point was past the last entry,
724 * set the new insertion point accordingly.
725 */
726 if (index == from)
727 newindex = to;
728 *indexp = newindex;
729 /*
730 * Adjust the leaf header values.
731 */
732 be16_add_cpu(&leaf->hdr.count, -(from - to));
733 leaf->hdr.stale = cpu_to_be16(1);
734 /*
735 * Remember the low/high stale value only in the "right"
736 * direction.
737 */
738 if (lowstale >= newindex)
739 lowstale = -1;
740 else
741 highstale = be16_to_cpu(leaf->hdr.count);
742 *highlogp = be16_to_cpu(leaf->hdr.count) - 1;
743 *lowstalep = lowstale;
744 *highstalep = highstale;
745 }
746
747 /*
748 * Getdents (readdir) for leaf and node directories.
749 * This reads the data blocks only, so is the same for both forms.
750 */
751 int /* error */
752 xfs_dir2_leaf_getdents(
753 xfs_inode_t *dp, /* incore directory inode */
754 void *dirent,
755 size_t bufsize,
756 xfs_off_t *offset,
757 filldir_t filldir)
758 {
759 xfs_dabuf_t *bp; /* data block buffer */
760 int byteoff; /* offset in current block */
761 xfs_dir2_db_t curdb; /* db for current block */
762 xfs_dir2_off_t curoff; /* current overall offset */
763 xfs_dir2_data_t *data; /* data block structure */
764 xfs_dir2_data_entry_t *dep; /* data entry */
765 xfs_dir2_data_unused_t *dup; /* unused entry */
766 int error = 0; /* error return value */
767 int i; /* temporary loop index */
768 int j; /* temporary loop index */
769 int length; /* temporary length value */
770 xfs_bmbt_irec_t *map; /* map vector for blocks */
771 xfs_extlen_t map_blocks; /* number of fsbs in map */
772 xfs_dablk_t map_off; /* last mapped file offset */
773 int map_size; /* total entries in *map */
774 int map_valid; /* valid entries in *map */
775 xfs_mount_t *mp; /* filesystem mount point */
776 xfs_dir2_off_t newoff; /* new curoff after new blk */
777 int nmap; /* mappings to ask xfs_bmapi */
778 char *ptr = NULL; /* pointer to current data */
779 int ra_current; /* number of read-ahead blks */
780 int ra_index; /* *map index for read-ahead */
781 int ra_offset; /* map entry offset for ra */
782 int ra_want; /* readahead count wanted */
783
784 /*
785 * If the offset is at or past the largest allowed value,
786 * give up right away.
787 */
788 if (*offset >= XFS_DIR2_MAX_DATAPTR)
789 return 0;
790
791 mp = dp->i_mount;
792
793 /*
794 * Set up to bmap a number of blocks based on the caller's
795 * buffer size, the directory block size, and the filesystem
796 * block size.
797 */
798 map_size = howmany(bufsize + mp->m_dirblksize, mp->m_sb.sb_blocksize);
799 map = kmem_alloc(map_size * sizeof(*map), KM_SLEEP);
800 map_valid = ra_index = ra_offset = ra_current = map_blocks = 0;
801 bp = NULL;
802
803 /*
804 * Inside the loop we keep the main offset value as a byte offset
805 * in the directory file.
806 */
807 curoff = xfs_dir2_dataptr_to_byte(mp, *offset);
808
809 /*
810 * Force this conversion through db so we truncate the offset
811 * down to get the start of the data block.
812 */
813 map_off = xfs_dir2_db_to_da(mp, xfs_dir2_byte_to_db(mp, curoff));
814 /*
815 * Loop over directory entries until we reach the end offset.
816 * Get more blocks and readahead as necessary.
817 */
818 while (curoff < XFS_DIR2_LEAF_OFFSET) {
819 /*
820 * If we have no buffer, or we're off the end of the
821 * current buffer, need to get another one.
822 */
823 if (!bp || ptr >= (char *)bp->data + mp->m_dirblksize) {
824 /*
825 * If we have a buffer, we need to release it and
826 * take it out of the mapping.
827 */
828 if (bp) {
829 xfs_da_brelse(NULL, bp);
830 bp = NULL;
831 map_blocks -= mp->m_dirblkfsbs;
832 /*
833 * Loop to get rid of the extents for the
834 * directory block.
835 */
836 for (i = mp->m_dirblkfsbs; i > 0; ) {
837 j = MIN((int)map->br_blockcount, i);
838 map->br_blockcount -= j;
839 map->br_startblock += j;
840 map->br_startoff += j;
841 /*
842 * If mapping is done, pitch it from
843 * the table.
844 */
845 if (!map->br_blockcount && --map_valid)
846 memmove(&map[0], &map[1],
847 sizeof(map[0]) *
848 map_valid);
849 i -= j;
850 }
851 }
852 /*
853 * Recalculate the readahead blocks wanted.
854 */
855 ra_want = howmany(bufsize + mp->m_dirblksize,
856 mp->m_sb.sb_blocksize) - 1;
857 ASSERT(ra_want >= 0);
858
859 /*
860 * If we don't have as many as we want, and we haven't
861 * run out of data blocks, get some more mappings.
862 */
863 if (1 + ra_want > map_blocks &&
864 map_off <
865 xfs_dir2_byte_to_da(mp, XFS_DIR2_LEAF_OFFSET)) {
866 /*
867 * Get more bmaps, fill in after the ones
868 * we already have in the table.
869 */
870 nmap = map_size - map_valid;
871 error = xfs_bmapi(NULL, dp,
872 map_off,
873 xfs_dir2_byte_to_da(mp,
874 XFS_DIR2_LEAF_OFFSET) - map_off,
875 XFS_BMAPI_METADATA, NULL, 0,
876 &map[map_valid], &nmap, NULL);
877 /*
878 * Don't know if we should ignore this or
879 * try to return an error.
880 * The trouble with returning errors
881 * is that readdir will just stop without
882 * actually passing the error through.
883 */
884 if (error)
885 break; /* XXX */
886 /*
887 * If we got all the mappings we asked for,
888 * set the final map offset based on the
889 * last bmap value received.
890 * Otherwise, we've reached the end.
891 */
892 if (nmap == map_size - map_valid)
893 map_off =
894 map[map_valid + nmap - 1].br_startoff +
895 map[map_valid + nmap - 1].br_blockcount;
896 else
897 map_off =
898 xfs_dir2_byte_to_da(mp,
899 XFS_DIR2_LEAF_OFFSET);
900 /*
901 * Look for holes in the mapping, and
902 * eliminate them. Count up the valid blocks.
903 */
904 for (i = map_valid; i < map_valid + nmap; ) {
905 if (map[i].br_startblock ==
906 HOLESTARTBLOCK) {
907 nmap--;
908 length = map_valid + nmap - i;
909 if (length)
910 memmove(&map[i],
911 &map[i + 1],
912 sizeof(map[i]) *
913 length);
914 } else {
915 map_blocks +=
916 map[i].br_blockcount;
917 i++;
918 }
919 }
920 map_valid += nmap;
921 }
922 /*
923 * No valid mappings, so no more data blocks.
924 */
925 if (!map_valid) {
926 curoff = xfs_dir2_da_to_byte(mp, map_off);
927 break;
928 }
929 /*
930 * Read the directory block starting at the first
931 * mapping.
932 */
933 curdb = xfs_dir2_da_to_db(mp, map->br_startoff);
934 error = xfs_da_read_buf(NULL, dp, map->br_startoff,
935 map->br_blockcount >= mp->m_dirblkfsbs ?
936 XFS_FSB_TO_DADDR(mp, map->br_startblock) :
937 -1,
938 &bp, XFS_DATA_FORK);
939 /*
940 * Should just skip over the data block instead
941 * of giving up.
942 */
943 if (error)
944 break; /* XXX */
945 /*
946 * Adjust the current amount of read-ahead: we just
947 * read a block that was previously ra.
948 */
949 if (ra_current)
950 ra_current -= mp->m_dirblkfsbs;
951 /*
952 * Do we need more readahead?
953 */
954 for (ra_index = ra_offset = i = 0;
955 ra_want > ra_current && i < map_blocks;
956 i += mp->m_dirblkfsbs) {
957 ASSERT(ra_index < map_valid);
958 /*
959 * Read-ahead a contiguous directory block.
960 */
961 if (i > ra_current &&
962 map[ra_index].br_blockcount >=
963 mp->m_dirblkfsbs) {
964 xfs_baread(mp->m_ddev_targp,
965 XFS_FSB_TO_DADDR(mp,
966 map[ra_index].br_startblock +
967 ra_offset),
968 (int)BTOBB(mp->m_dirblksize));
969 ra_current = i;
970 }
971 /*
972 * Read-ahead a non-contiguous directory block.
973 * This doesn't use our mapping, but this
974 * is a very rare case.
975 */
976 else if (i > ra_current) {
977 (void)xfs_da_reada_buf(NULL, dp,
978 map[ra_index].br_startoff +
979 ra_offset, XFS_DATA_FORK);
980 ra_current = i;
981 }
982 /*
983 * Advance offset through the mapping table.
984 */
985 for (j = 0; j < mp->m_dirblkfsbs; j++) {
986 /*
987 * The rest of this extent but not
988 * more than a dir block.
989 */
990 length = MIN(mp->m_dirblkfsbs,
991 (int)(map[ra_index].br_blockcount -
992 ra_offset));
993 j += length;
994 ra_offset += length;
995 /*
996 * Advance to the next mapping if
997 * this one is used up.
998 */
999 if (ra_offset ==
1000 map[ra_index].br_blockcount) {
1001 ra_offset = 0;
1002 ra_index++;
1003 }
1004 }
1005 }
1006 /*
1007 * Having done a read, we need to set a new offset.
1008 */
1009 newoff = xfs_dir2_db_off_to_byte(mp, curdb, 0);
1010 /*
1011 * Start of the current block.
1012 */
1013 if (curoff < newoff)
1014 curoff = newoff;
1015 /*
1016 * Make sure we're in the right block.
1017 */
1018 else if (curoff > newoff)
1019 ASSERT(xfs_dir2_byte_to_db(mp, curoff) ==
1020 curdb);
1021 data = bp->data;
1022 xfs_dir2_data_check(dp, bp);
1023 /*
1024 * Find our position in the block.
1025 */
1026 ptr = (char *)&data->u;
1027 byteoff = xfs_dir2_byte_to_off(mp, curoff);
1028 /*
1029 * Skip past the header.
1030 */
1031 if (byteoff == 0)
1032 curoff += (uint)sizeof(data->hdr);
1033 /*
1034 * Skip past entries until we reach our offset.
1035 */
1036 else {
1037 while ((char *)ptr - (char *)data < byteoff) {
1038 dup = (xfs_dir2_data_unused_t *)ptr;
1039
1040 if (be16_to_cpu(dup->freetag)
1041 == XFS_DIR2_DATA_FREE_TAG) {
1042
1043 length = be16_to_cpu(dup->length);
1044 ptr += length;
1045 continue;
1046 }
1047 dep = (xfs_dir2_data_entry_t *)ptr;
1048 length =
1049 xfs_dir2_data_entsize(dep->namelen);
1050 ptr += length;
1051 }
1052 /*
1053 * Now set our real offset.
1054 */
1055 curoff =
1056 xfs_dir2_db_off_to_byte(mp,
1057 xfs_dir2_byte_to_db(mp, curoff),
1058 (char *)ptr - (char *)data);
1059 if (ptr >= (char *)data + mp->m_dirblksize) {
1060 continue;
1061 }
1062 }
1063 }
1064 /*
1065 * We have a pointer to an entry.
1066 * Is it a live one?
1067 */
1068 dup = (xfs_dir2_data_unused_t *)ptr;
1069 /*
1070 * No, it's unused, skip over it.
1071 */
1072 if (be16_to_cpu(dup->freetag) == XFS_DIR2_DATA_FREE_TAG) {
1073 length = be16_to_cpu(dup->length);
1074 ptr += length;
1075 curoff += length;
1076 continue;
1077 }
1078
1079 dep = (xfs_dir2_data_entry_t *)ptr;
1080 length = xfs_dir2_data_entsize(dep->namelen);
1081
1082 if (filldir(dirent, (char *)dep->name, dep->namelen,
1083 xfs_dir2_byte_to_dataptr(mp, curoff) & 0x7fffffff,
1084 be64_to_cpu(dep->inumber), DT_UNKNOWN))
1085 break;
1086
1087 /*
1088 * Advance to next entry in the block.
1089 */
1090 ptr += length;
1091 curoff += length;
1092 /* bufsize may have just been a guess; don't go negative */
1093 bufsize = bufsize > length ? bufsize - length : 0;
1094 }
1095
1096 /*
1097 * All done. Set output offset value to current offset.
1098 */
1099 if (curoff > xfs_dir2_dataptr_to_byte(mp, XFS_DIR2_MAX_DATAPTR))
1100 *offset = XFS_DIR2_MAX_DATAPTR & 0x7fffffff;
1101 else
1102 *offset = xfs_dir2_byte_to_dataptr(mp, curoff) & 0x7fffffff;
1103 kmem_free(map);
1104 if (bp)
1105 xfs_da_brelse(NULL, bp);
1106 return error;
1107 }
1108
1109 /*
1110 * Initialize a new leaf block, leaf1 or leafn magic accepted.
1111 */
1112 int
1113 xfs_dir2_leaf_init(
1114 xfs_da_args_t *args, /* operation arguments */
1115 xfs_dir2_db_t bno, /* directory block number */
1116 xfs_dabuf_t **bpp, /* out: leaf buffer */
1117 int magic) /* magic number for block */
1118 {
1119 xfs_dabuf_t *bp; /* leaf buffer */
1120 xfs_inode_t *dp; /* incore directory inode */
1121 int error; /* error return code */
1122 xfs_dir2_leaf_t *leaf; /* leaf structure */
1123 xfs_dir2_leaf_tail_t *ltp; /* leaf tail structure */
1124 xfs_mount_t *mp; /* filesystem mount point */
1125 xfs_trans_t *tp; /* transaction pointer */
1126
1127 dp = args->dp;
1128 ASSERT(dp != NULL);
1129 tp = args->trans;
1130 mp = dp->i_mount;
1131 ASSERT(bno >= XFS_DIR2_LEAF_FIRSTDB(mp) &&
1132 bno < XFS_DIR2_FREE_FIRSTDB(mp));
1133 /*
1134 * Get the buffer for the block.
1135 */
1136 error = xfs_da_get_buf(tp, dp, xfs_dir2_db_to_da(mp, bno), -1, &bp,
1137 XFS_DATA_FORK);
1138 if (error) {
1139 return error;
1140 }
1141 ASSERT(bp != NULL);
1142 leaf = bp->data;
1143 /*
1144 * Initialize the header.
1145 */
1146 leaf->hdr.info.magic = cpu_to_be16(magic);
1147 leaf->hdr.info.forw = 0;
1148 leaf->hdr.info.back = 0;
1149 leaf->hdr.count = 0;
1150 leaf->hdr.stale = 0;
1151 xfs_dir2_leaf_log_header(tp, bp);
1152 /*
1153 * If it's a leaf-format directory initialize the tail.
1154 * In this case our caller has the real bests table to copy into
1155 * the block.
1156 */
1157 if (magic == XFS_DIR2_LEAF1_MAGIC) {
1158 ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1159 ltp->bestcount = 0;
1160 xfs_dir2_leaf_log_tail(tp, bp);
1161 }
1162 *bpp = bp;
1163 return 0;
1164 }
1165
1166 /*
1167 * Log the bests entries indicated from a leaf1 block.
1168 */
1169 static void
1170 xfs_dir2_leaf_log_bests(
1171 xfs_trans_t *tp, /* transaction pointer */
1172 xfs_dabuf_t *bp, /* leaf buffer */
1173 int first, /* first entry to log */
1174 int last) /* last entry to log */
1175 {
1176 __be16 *firstb; /* pointer to first entry */
1177 __be16 *lastb; /* pointer to last entry */
1178 xfs_dir2_leaf_t *leaf; /* leaf structure */
1179 xfs_dir2_leaf_tail_t *ltp; /* leaf tail structure */
1180
1181 leaf = bp->data;
1182 ASSERT(be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAF1_MAGIC);
1183 ltp = xfs_dir2_leaf_tail_p(tp->t_mountp, leaf);
1184 firstb = xfs_dir2_leaf_bests_p(ltp) + first;
1185 lastb = xfs_dir2_leaf_bests_p(ltp) + last;
1186 xfs_da_log_buf(tp, bp, (uint)((char *)firstb - (char *)leaf),
1187 (uint)((char *)lastb - (char *)leaf + sizeof(*lastb) - 1));
1188 }
1189
1190 /*
1191 * Log the leaf entries indicated from a leaf1 or leafn block.
1192 */
1193 void
1194 xfs_dir2_leaf_log_ents(
1195 xfs_trans_t *tp, /* transaction pointer */
1196 xfs_dabuf_t *bp, /* leaf buffer */
1197 int first, /* first entry to log */
1198 int last) /* last entry to log */
1199 {
1200 xfs_dir2_leaf_entry_t *firstlep; /* pointer to first entry */
1201 xfs_dir2_leaf_entry_t *lastlep; /* pointer to last entry */
1202 xfs_dir2_leaf_t *leaf; /* leaf structure */
1203
1204 leaf = bp->data;
1205 ASSERT(be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAF1_MAGIC ||
1206 be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAFN_MAGIC);
1207 firstlep = &leaf->ents[first];
1208 lastlep = &leaf->ents[last];
1209 xfs_da_log_buf(tp, bp, (uint)((char *)firstlep - (char *)leaf),
1210 (uint)((char *)lastlep - (char *)leaf + sizeof(*lastlep) - 1));
1211 }
1212
1213 /*
1214 * Log the header of the leaf1 or leafn block.
1215 */
1216 void
1217 xfs_dir2_leaf_log_header(
1218 xfs_trans_t *tp, /* transaction pointer */
1219 xfs_dabuf_t *bp) /* leaf buffer */
1220 {
1221 xfs_dir2_leaf_t *leaf; /* leaf structure */
1222
1223 leaf = bp->data;
1224 ASSERT(be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAF1_MAGIC ||
1225 be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAFN_MAGIC);
1226 xfs_da_log_buf(tp, bp, (uint)((char *)&leaf->hdr - (char *)leaf),
1227 (uint)(sizeof(leaf->hdr) - 1));
1228 }
1229
1230 /*
1231 * Log the tail of the leaf1 block.
1232 */
1233 STATIC void
1234 xfs_dir2_leaf_log_tail(
1235 xfs_trans_t *tp, /* transaction pointer */
1236 xfs_dabuf_t *bp) /* leaf buffer */
1237 {
1238 xfs_dir2_leaf_t *leaf; /* leaf structure */
1239 xfs_dir2_leaf_tail_t *ltp; /* leaf tail structure */
1240 xfs_mount_t *mp; /* filesystem mount point */
1241
1242 mp = tp->t_mountp;
1243 leaf = bp->data;
1244 ASSERT(be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAF1_MAGIC);
1245 ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1246 xfs_da_log_buf(tp, bp, (uint)((char *)ltp - (char *)leaf),
1247 (uint)(mp->m_dirblksize - 1));
1248 }
1249
1250 /*
1251 * Look up the entry referred to by args in the leaf format directory.
1252 * Most of the work is done by the xfs_dir2_leaf_lookup_int routine which
1253 * is also used by the node-format code.
1254 */
1255 int
1256 xfs_dir2_leaf_lookup(
1257 xfs_da_args_t *args) /* operation arguments */
1258 {
1259 xfs_dabuf_t *dbp; /* data block buffer */
1260 xfs_dir2_data_entry_t *dep; /* data block entry */
1261 xfs_inode_t *dp; /* incore directory inode */
1262 int error; /* error return code */
1263 int index; /* found entry index */
1264 xfs_dabuf_t *lbp; /* leaf buffer */
1265 xfs_dir2_leaf_t *leaf; /* leaf structure */
1266 xfs_dir2_leaf_entry_t *lep; /* leaf entry */
1267 xfs_trans_t *tp; /* transaction pointer */
1268
1269 trace_xfs_dir2_leaf_lookup(args);
1270
1271 /*
1272 * Look up name in the leaf block, returning both buffers and index.
1273 */
1274 if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1275 return error;
1276 }
1277 tp = args->trans;
1278 dp = args->dp;
1279 xfs_dir2_leaf_check(dp, lbp);
1280 leaf = lbp->data;
1281 /*
1282 * Get to the leaf entry and contained data entry address.
1283 */
1284 lep = &leaf->ents[index];
1285 /*
1286 * Point to the data entry.
1287 */
1288 dep = (xfs_dir2_data_entry_t *)
1289 ((char *)dbp->data +
1290 xfs_dir2_dataptr_to_off(dp->i_mount, be32_to_cpu(lep->address)));
1291 /*
1292 * Return the found inode number & CI name if appropriate
1293 */
1294 args->inumber = be64_to_cpu(dep->inumber);
1295 error = xfs_dir_cilookup_result(args, dep->name, dep->namelen);
1296 xfs_da_brelse(tp, dbp);
1297 xfs_da_brelse(tp, lbp);
1298 return XFS_ERROR(error);
1299 }
1300
1301 /*
1302 * Look up name/hash in the leaf block.
1303 * Fill in indexp with the found index, and dbpp with the data buffer.
1304 * If not found dbpp will be NULL, and ENOENT comes back.
1305 * lbpp will always be filled in with the leaf buffer unless there's an error.
1306 */
1307 static int /* error */
1308 xfs_dir2_leaf_lookup_int(
1309 xfs_da_args_t *args, /* operation arguments */
1310 xfs_dabuf_t **lbpp, /* out: leaf buffer */
1311 int *indexp, /* out: index in leaf block */
1312 xfs_dabuf_t **dbpp) /* out: data buffer */
1313 {
1314 xfs_dir2_db_t curdb = -1; /* current data block number */
1315 xfs_dabuf_t *dbp = NULL; /* data buffer */
1316 xfs_dir2_data_entry_t *dep; /* data entry */
1317 xfs_inode_t *dp; /* incore directory inode */
1318 int error; /* error return code */
1319 int index; /* index in leaf block */
1320 xfs_dabuf_t *lbp; /* leaf buffer */
1321 xfs_dir2_leaf_entry_t *lep; /* leaf entry */
1322 xfs_dir2_leaf_t *leaf; /* leaf structure */
1323 xfs_mount_t *mp; /* filesystem mount point */
1324 xfs_dir2_db_t newdb; /* new data block number */
1325 xfs_trans_t *tp; /* transaction pointer */
1326 xfs_dir2_db_t cidb = -1; /* case match data block no. */
1327 enum xfs_dacmp cmp; /* name compare result */
1328
1329 dp = args->dp;
1330 tp = args->trans;
1331 mp = dp->i_mount;
1332 /*
1333 * Read the leaf block into the buffer.
1334 */
1335 error = xfs_da_read_buf(tp, dp, mp->m_dirleafblk, -1, &lbp,
1336 XFS_DATA_FORK);
1337 if (error)
1338 return error;
1339 *lbpp = lbp;
1340 leaf = lbp->data;
1341 xfs_dir2_leaf_check(dp, lbp);
1342 /*
1343 * Look for the first leaf entry with our hash value.
1344 */
1345 index = xfs_dir2_leaf_search_hash(args, lbp);
1346 /*
1347 * Loop over all the entries with the right hash value
1348 * looking to match the name.
1349 */
1350 for (lep = &leaf->ents[index]; index < be16_to_cpu(leaf->hdr.count) &&
1351 be32_to_cpu(lep->hashval) == args->hashval;
1352 lep++, index++) {
1353 /*
1354 * Skip over stale leaf entries.
1355 */
1356 if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
1357 continue;
1358 /*
1359 * Get the new data block number.
1360 */
1361 newdb = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
1362 /*
1363 * If it's not the same as the old data block number,
1364 * need to pitch the old one and read the new one.
1365 */
1366 if (newdb != curdb) {
1367 if (dbp)
1368 xfs_da_brelse(tp, dbp);
1369 error = xfs_da_read_buf(tp, dp,
1370 xfs_dir2_db_to_da(mp, newdb),
1371 -1, &dbp, XFS_DATA_FORK);
1372 if (error) {
1373 xfs_da_brelse(tp, lbp);
1374 return error;
1375 }
1376 xfs_dir2_data_check(dp, dbp);
1377 curdb = newdb;
1378 }
1379 /*
1380 * Point to the data entry.
1381 */
1382 dep = (xfs_dir2_data_entry_t *)((char *)dbp->data +
1383 xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address)));
1384 /*
1385 * Compare name and if it's an exact match, return the index
1386 * and buffer. If it's the first case-insensitive match, store
1387 * the index and buffer and continue looking for an exact match.
1388 */
1389 cmp = mp->m_dirnameops->compname(args, dep->name, dep->namelen);
1390 if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) {
1391 args->cmpresult = cmp;
1392 *indexp = index;
1393 /* case exact match: return the current buffer. */
1394 if (cmp == XFS_CMP_EXACT) {
1395 *dbpp = dbp;
1396 return 0;
1397 }
1398 cidb = curdb;
1399 }
1400 }
1401 ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
1402 /*
1403 * Here, we can only be doing a lookup (not a rename or remove).
1404 * If a case-insensitive match was found earlier, re-read the
1405 * appropriate data block if required and return it.
1406 */
1407 if (args->cmpresult == XFS_CMP_CASE) {
1408 ASSERT(cidb != -1);
1409 if (cidb != curdb) {
1410 xfs_da_brelse(tp, dbp);
1411 error = xfs_da_read_buf(tp, dp,
1412 xfs_dir2_db_to_da(mp, cidb),
1413 -1, &dbp, XFS_DATA_FORK);
1414 if (error) {
1415 xfs_da_brelse(tp, lbp);
1416 return error;
1417 }
1418 }
1419 *dbpp = dbp;
1420 return 0;
1421 }
1422 /*
1423 * No match found, return ENOENT.
1424 */
1425 ASSERT(cidb == -1);
1426 if (dbp)
1427 xfs_da_brelse(tp, dbp);
1428 xfs_da_brelse(tp, lbp);
1429 return XFS_ERROR(ENOENT);
1430 }
1431
1432 /*
1433 * Remove an entry from a leaf format directory.
1434 */
1435 int /* error */
1436 xfs_dir2_leaf_removename(
1437 xfs_da_args_t *args) /* operation arguments */
1438 {
1439 __be16 *bestsp; /* leaf block best freespace */
1440 xfs_dir2_data_t *data; /* data block structure */
1441 xfs_dir2_db_t db; /* data block number */
1442 xfs_dabuf_t *dbp; /* data block buffer */
1443 xfs_dir2_data_entry_t *dep; /* data entry structure */
1444 xfs_inode_t *dp; /* incore directory inode */
1445 int error; /* error return code */
1446 xfs_dir2_db_t i; /* temporary data block # */
1447 int index; /* index into leaf entries */
1448 xfs_dabuf_t *lbp; /* leaf buffer */
1449 xfs_dir2_leaf_t *leaf; /* leaf structure */
1450 xfs_dir2_leaf_entry_t *lep; /* leaf entry */
1451 xfs_dir2_leaf_tail_t *ltp; /* leaf tail structure */
1452 xfs_mount_t *mp; /* filesystem mount point */
1453 int needlog; /* need to log data header */
1454 int needscan; /* need to rescan data frees */
1455 xfs_dir2_data_off_t oldbest; /* old value of best free */
1456 xfs_trans_t *tp; /* transaction pointer */
1457
1458 trace_xfs_dir2_leaf_removename(args);
1459
1460 /*
1461 * Lookup the leaf entry, get the leaf and data blocks read in.
1462 */
1463 if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1464 return error;
1465 }
1466 dp = args->dp;
1467 tp = args->trans;
1468 mp = dp->i_mount;
1469 leaf = lbp->data;
1470 data = dbp->data;
1471 xfs_dir2_data_check(dp, dbp);
1472 /*
1473 * Point to the leaf entry, use that to point to the data entry.
1474 */
1475 lep = &leaf->ents[index];
1476 db = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
1477 dep = (xfs_dir2_data_entry_t *)
1478 ((char *)data + xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address)));
1479 needscan = needlog = 0;
1480 oldbest = be16_to_cpu(data->hdr.bestfree[0].length);
1481 ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1482 bestsp = xfs_dir2_leaf_bests_p(ltp);
1483 ASSERT(be16_to_cpu(bestsp[db]) == oldbest);
1484 /*
1485 * Mark the former data entry unused.
1486 */
1487 xfs_dir2_data_make_free(tp, dbp,
1488 (xfs_dir2_data_aoff_t)((char *)dep - (char *)data),
1489 xfs_dir2_data_entsize(dep->namelen), &needlog, &needscan);
1490 /*
1491 * We just mark the leaf entry stale by putting a null in it.
1492 */
1493 be16_add_cpu(&leaf->hdr.stale, 1);
1494 xfs_dir2_leaf_log_header(tp, lbp);
1495 lep->address = cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
1496 xfs_dir2_leaf_log_ents(tp, lbp, index, index);
1497 /*
1498 * Scan the freespace in the data block again if necessary,
1499 * log the data block header if necessary.
1500 */
1501 if (needscan)
1502 xfs_dir2_data_freescan(mp, data, &needlog);
1503 if (needlog)
1504 xfs_dir2_data_log_header(tp, dbp);
1505 /*
1506 * If the longest freespace in the data block has changed,
1507 * put the new value in the bests table and log that.
1508 */
1509 if (be16_to_cpu(data->hdr.bestfree[0].length) != oldbest) {
1510 bestsp[db] = data->hdr.bestfree[0].length;
1511 xfs_dir2_leaf_log_bests(tp, lbp, db, db);
1512 }
1513 xfs_dir2_data_check(dp, dbp);
1514 /*
1515 * If the data block is now empty then get rid of the data block.
1516 */
1517 if (be16_to_cpu(data->hdr.bestfree[0].length) ==
1518 mp->m_dirblksize - (uint)sizeof(data->hdr)) {
1519 ASSERT(db != mp->m_dirdatablk);
1520 if ((error = xfs_dir2_shrink_inode(args, db, dbp))) {
1521 /*
1522 * Nope, can't get rid of it because it caused
1523 * allocation of a bmap btree block to do so.
1524 * Just go on, returning success, leaving the
1525 * empty block in place.
1526 */
1527 if (error == ENOSPC && args->total == 0) {
1528 xfs_da_buf_done(dbp);
1529 error = 0;
1530 }
1531 xfs_dir2_leaf_check(dp, lbp);
1532 xfs_da_buf_done(lbp);
1533 return error;
1534 }
1535 dbp = NULL;
1536 /*
1537 * If this is the last data block then compact the
1538 * bests table by getting rid of entries.
1539 */
1540 if (db == be32_to_cpu(ltp->bestcount) - 1) {
1541 /*
1542 * Look for the last active entry (i).
1543 */
1544 for (i = db - 1; i > 0; i--) {
1545 if (be16_to_cpu(bestsp[i]) != NULLDATAOFF)
1546 break;
1547 }
1548 /*
1549 * Copy the table down so inactive entries at the
1550 * end are removed.
1551 */
1552 memmove(&bestsp[db - i], bestsp,
1553 (be32_to_cpu(ltp->bestcount) - (db - i)) * sizeof(*bestsp));
1554 be32_add_cpu(&ltp->bestcount, -(db - i));
1555 xfs_dir2_leaf_log_tail(tp, lbp);
1556 xfs_dir2_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1557 } else
1558 bestsp[db] = cpu_to_be16(NULLDATAOFF);
1559 }
1560 /*
1561 * If the data block was not the first one, drop it.
1562 */
1563 else if (db != mp->m_dirdatablk && dbp != NULL) {
1564 xfs_da_buf_done(dbp);
1565 dbp = NULL;
1566 }
1567 xfs_dir2_leaf_check(dp, lbp);
1568 /*
1569 * See if we can convert to block form.
1570 */
1571 return xfs_dir2_leaf_to_block(args, lbp, dbp);
1572 }
1573
1574 /*
1575 * Replace the inode number in a leaf format directory entry.
1576 */
1577 int /* error */
1578 xfs_dir2_leaf_replace(
1579 xfs_da_args_t *args) /* operation arguments */
1580 {
1581 xfs_dabuf_t *dbp; /* data block buffer */
1582 xfs_dir2_data_entry_t *dep; /* data block entry */
1583 xfs_inode_t *dp; /* incore directory inode */
1584 int error; /* error return code */
1585 int index; /* index of leaf entry */
1586 xfs_dabuf_t *lbp; /* leaf buffer */
1587 xfs_dir2_leaf_t *leaf; /* leaf structure */
1588 xfs_dir2_leaf_entry_t *lep; /* leaf entry */
1589 xfs_trans_t *tp; /* transaction pointer */
1590
1591 trace_xfs_dir2_leaf_replace(args);
1592
1593 /*
1594 * Look up the entry.
1595 */
1596 if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1597 return error;
1598 }
1599 dp = args->dp;
1600 leaf = lbp->data;
1601 /*
1602 * Point to the leaf entry, get data address from it.
1603 */
1604 lep = &leaf->ents[index];
1605 /*
1606 * Point to the data entry.
1607 */
1608 dep = (xfs_dir2_data_entry_t *)
1609 ((char *)dbp->data +
1610 xfs_dir2_dataptr_to_off(dp->i_mount, be32_to_cpu(lep->address)));
1611 ASSERT(args->inumber != be64_to_cpu(dep->inumber));
1612 /*
1613 * Put the new inode number in, log it.
1614 */
1615 dep->inumber = cpu_to_be64(args->inumber);
1616 tp = args->trans;
1617 xfs_dir2_data_log_entry(tp, dbp, dep);
1618 xfs_da_buf_done(dbp);
1619 xfs_dir2_leaf_check(dp, lbp);
1620 xfs_da_brelse(tp, lbp);
1621 return 0;
1622 }
1623
1624 /*
1625 * Return index in the leaf block (lbp) which is either the first
1626 * one with this hash value, or if there are none, the insert point
1627 * for that hash value.
1628 */
1629 int /* index value */
1630 xfs_dir2_leaf_search_hash(
1631 xfs_da_args_t *args, /* operation arguments */
1632 xfs_dabuf_t *lbp) /* leaf buffer */
1633 {
1634 xfs_dahash_t hash=0; /* hash from this entry */
1635 xfs_dahash_t hashwant; /* hash value looking for */
1636 int high; /* high leaf index */
1637 int low; /* low leaf index */
1638 xfs_dir2_leaf_t *leaf; /* leaf structure */
1639 xfs_dir2_leaf_entry_t *lep; /* leaf entry */
1640 int mid=0; /* current leaf index */
1641
1642 leaf = lbp->data;
1643 #ifndef __KERNEL__
1644 if (!leaf->hdr.count)
1645 return 0;
1646 #endif
1647 /*
1648 * Note, the table cannot be empty, so we have to go through the loop.
1649 * Binary search the leaf entries looking for our hash value.
1650 */
1651 for (lep = leaf->ents, low = 0, high = be16_to_cpu(leaf->hdr.count) - 1,
1652 hashwant = args->hashval;
1653 low <= high; ) {
1654 mid = (low + high) >> 1;
1655 if ((hash = be32_to_cpu(lep[mid].hashval)) == hashwant)
1656 break;
1657 if (hash < hashwant)
1658 low = mid + 1;
1659 else
1660 high = mid - 1;
1661 }
1662 /*
1663 * Found one, back up through all the equal hash values.
1664 */
1665 if (hash == hashwant) {
1666 while (mid > 0 && be32_to_cpu(lep[mid - 1].hashval) == hashwant) {
1667 mid--;
1668 }
1669 }
1670 /*
1671 * Need to point to an entry higher than ours.
1672 */
1673 else if (hash < hashwant)
1674 mid++;
1675 return mid;
1676 }
1677
1678 /*
1679 * Trim off a trailing data block. We know it's empty since the leaf
1680 * freespace table says so.
1681 */
1682 int /* error */
1683 xfs_dir2_leaf_trim_data(
1684 xfs_da_args_t *args, /* operation arguments */
1685 xfs_dabuf_t *lbp, /* leaf buffer */
1686 xfs_dir2_db_t db) /* data block number */
1687 {
1688 __be16 *bestsp; /* leaf bests table */
1689 #ifdef DEBUG
1690 xfs_dir2_data_t *data; /* data block structure */
1691 #endif
1692 xfs_dabuf_t *dbp; /* data block buffer */
1693 xfs_inode_t *dp; /* incore directory inode */
1694 int error; /* error return value */
1695 xfs_dir2_leaf_t *leaf; /* leaf structure */
1696 xfs_dir2_leaf_tail_t *ltp; /* leaf tail structure */
1697 xfs_mount_t *mp; /* filesystem mount point */
1698 xfs_trans_t *tp; /* transaction pointer */
1699
1700 dp = args->dp;
1701 mp = dp->i_mount;
1702 tp = args->trans;
1703 /*
1704 * Read the offending data block. We need its buffer.
1705 */
1706 if ((error = xfs_da_read_buf(tp, dp, xfs_dir2_db_to_da(mp, db), -1, &dbp,
1707 XFS_DATA_FORK))) {
1708 return error;
1709 }
1710 #ifdef DEBUG
1711 data = dbp->data;
1712 ASSERT(be32_to_cpu(data->hdr.magic) == XFS_DIR2_DATA_MAGIC);
1713 #endif
1714 /* this seems to be an error
1715 * data is only valid if DEBUG is defined?
1716 * RMC 09/08/1999
1717 */
1718
1719 leaf = lbp->data;
1720 ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1721 ASSERT(be16_to_cpu(data->hdr.bestfree[0].length) ==
1722 mp->m_dirblksize - (uint)sizeof(data->hdr));
1723 ASSERT(db == be32_to_cpu(ltp->bestcount) - 1);
1724 /*
1725 * Get rid of the data block.
1726 */
1727 if ((error = xfs_dir2_shrink_inode(args, db, dbp))) {
1728 ASSERT(error != ENOSPC);
1729 xfs_da_brelse(tp, dbp);
1730 return error;
1731 }
1732 /*
1733 * Eliminate the last bests entry from the table.
1734 */
1735 bestsp = xfs_dir2_leaf_bests_p(ltp);
1736 be32_add_cpu(&ltp->bestcount, -1);
1737 memmove(&bestsp[1], &bestsp[0], be32_to_cpu(ltp->bestcount) * sizeof(*bestsp));
1738 xfs_dir2_leaf_log_tail(tp, lbp);
1739 xfs_dir2_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1740 return 0;
1741 }
1742
1743 /*
1744 * Convert node form directory to leaf form directory.
1745 * The root of the node form dir needs to already be a LEAFN block.
1746 * Just return if we can't do anything.
1747 */
1748 int /* error */
1749 xfs_dir2_node_to_leaf(
1750 xfs_da_state_t *state) /* directory operation state */
1751 {
1752 xfs_da_args_t *args; /* operation arguments */
1753 xfs_inode_t *dp; /* incore directory inode */
1754 int error; /* error return code */
1755 xfs_dabuf_t *fbp; /* buffer for freespace block */
1756 xfs_fileoff_t fo; /* freespace file offset */
1757 xfs_dir2_free_t *free; /* freespace structure */
1758 xfs_dabuf_t *lbp; /* buffer for leaf block */
1759 xfs_dir2_leaf_tail_t *ltp; /* tail of leaf structure */
1760 xfs_dir2_leaf_t *leaf; /* leaf structure */
1761 xfs_mount_t *mp; /* filesystem mount point */
1762 int rval; /* successful free trim? */
1763 xfs_trans_t *tp; /* transaction pointer */
1764
1765 /*
1766 * There's more than a leaf level in the btree, so there must
1767 * be multiple leafn blocks. Give up.
1768 */
1769 if (state->path.active > 1)
1770 return 0;
1771 args = state->args;
1772
1773 trace_xfs_dir2_node_to_leaf(args);
1774
1775 mp = state->mp;
1776 dp = args->dp;
1777 tp = args->trans;
1778 /*
1779 * Get the last offset in the file.
1780 */
1781 if ((error = xfs_bmap_last_offset(tp, dp, &fo, XFS_DATA_FORK))) {
1782 return error;
1783 }
1784 fo -= mp->m_dirblkfsbs;
1785 /*
1786 * If there are freespace blocks other than the first one,
1787 * take this opportunity to remove trailing empty freespace blocks
1788 * that may have been left behind during no-space-reservation
1789 * operations.
1790 */
1791 while (fo > mp->m_dirfreeblk) {
1792 if ((error = xfs_dir2_node_trim_free(args, fo, &rval))) {
1793 return error;
1794 }
1795 if (rval)
1796 fo -= mp->m_dirblkfsbs;
1797 else
1798 return 0;
1799 }
1800 /*
1801 * Now find the block just before the freespace block.
1802 */
1803 if ((error = xfs_bmap_last_before(tp, dp, &fo, XFS_DATA_FORK))) {
1804 return error;
1805 }
1806 /*
1807 * If it's not the single leaf block, give up.
1808 */
1809 if (XFS_FSB_TO_B(mp, fo) > XFS_DIR2_LEAF_OFFSET + mp->m_dirblksize)
1810 return 0;
1811 lbp = state->path.blk[0].bp;
1812 leaf = lbp->data;
1813 ASSERT(be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAFN_MAGIC);
1814 /*
1815 * Read the freespace block.
1816 */
1817 if ((error = xfs_da_read_buf(tp, dp, mp->m_dirfreeblk, -1, &fbp,
1818 XFS_DATA_FORK))) {
1819 return error;
1820 }
1821 free = fbp->data;
1822 ASSERT(be32_to_cpu(free->hdr.magic) == XFS_DIR2_FREE_MAGIC);
1823 ASSERT(!free->hdr.firstdb);
1824 /*
1825 * Now see if the leafn and free data will fit in a leaf1.
1826 * If not, release the buffer and give up.
1827 */
1828 if ((uint)sizeof(leaf->hdr) +
1829 (be16_to_cpu(leaf->hdr.count) - be16_to_cpu(leaf->hdr.stale)) * (uint)sizeof(leaf->ents[0]) +
1830 be32_to_cpu(free->hdr.nvalid) * (uint)sizeof(leaf->bests[0]) +
1831 (uint)sizeof(leaf->tail) >
1832 mp->m_dirblksize) {
1833 xfs_da_brelse(tp, fbp);
1834 return 0;
1835 }
1836 /*
1837 * If the leaf has any stale entries in it, compress them out.
1838 * The compact routine will log the header.
1839 */
1840 if (be16_to_cpu(leaf->hdr.stale))
1841 xfs_dir2_leaf_compact(args, lbp);
1842 else
1843 xfs_dir2_leaf_log_header(tp, lbp);
1844 leaf->hdr.info.magic = cpu_to_be16(XFS_DIR2_LEAF1_MAGIC);
1845 /*
1846 * Set up the leaf tail from the freespace block.
1847 */
1848 ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1849 ltp->bestcount = free->hdr.nvalid;
1850 /*
1851 * Set up the leaf bests table.
1852 */
1853 memcpy(xfs_dir2_leaf_bests_p(ltp), free->bests,
1854 be32_to_cpu(ltp->bestcount) * sizeof(leaf->bests[0]));
1855 xfs_dir2_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1856 xfs_dir2_leaf_log_tail(tp, lbp);
1857 xfs_dir2_leaf_check(dp, lbp);
1858 /*
1859 * Get rid of the freespace block.
1860 */
1861 error = xfs_dir2_shrink_inode(args, XFS_DIR2_FREE_FIRSTDB(mp), fbp);
1862 if (error) {
1863 /*
1864 * This can't fail here because it can only happen when
1865 * punching out the middle of an extent, and this is an
1866 * isolated block.
1867 */
1868 ASSERT(error != ENOSPC);
1869 return error;
1870 }
1871 fbp = NULL;
1872 /*
1873 * Now see if we can convert the single-leaf directory
1874 * down to a block form directory.
1875 * This routine always kills the dabuf for the leaf, so
1876 * eliminate it from the path.
1877 */
1878 error = xfs_dir2_leaf_to_block(args, lbp, NULL);
1879 state->path.blk[0].bp = NULL;
1880 return error;
1881 }
Linus' kernel tree