Merge branch 'x86/doc' into x86/core
[linux-2.6] / fs / xfs / xfs_dir2_leaf.c
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_dmapi.h"
29 #include "xfs_mount.h"
30 #include "xfs_da_btree.h"
31 #include "xfs_bmap_btree.h"
32 #include "xfs_attr_sf.h"
33 #include "xfs_dir2_sf.h"
34 #include "xfs_dinode.h"
35 #include "xfs_inode.h"
36 #include "xfs_bmap.h"
37 #include "xfs_dir2_data.h"
38 #include "xfs_dir2_leaf.h"
39 #include "xfs_dir2_block.h"
40 #include "xfs_dir2_node.h"
41 #include "xfs_dir2_trace.h"
42 #include "xfs_error.h"
43
44 /*
45  * Local function declarations.
46  */
47 #ifdef DEBUG
48 static void xfs_dir2_leaf_check(xfs_inode_t *dp, xfs_dabuf_t *bp);
49 #else
50 #define xfs_dir2_leaf_check(dp, bp)
51 #endif
52 static int xfs_dir2_leaf_lookup_int(xfs_da_args_t *args, xfs_dabuf_t **lbpp,
53                                     int *indexp, xfs_dabuf_t **dbpp);
54 static void xfs_dir2_leaf_log_bests(struct xfs_trans *tp, struct xfs_dabuf *bp,
55                                     int first, int last);
56 static void xfs_dir2_leaf_log_tail(struct xfs_trans *tp, struct xfs_dabuf *bp);
57
58
59 /*
60  * Convert a block form directory to a leaf form directory.
61  */
62 int                                             /* error */
63 xfs_dir2_block_to_leaf(
64         xfs_da_args_t           *args,          /* operation arguments */
65         xfs_dabuf_t             *dbp)           /* input block's buffer */
66 {
67         __be16                  *bestsp;        /* leaf's bestsp entries */
68         xfs_dablk_t             blkno;          /* leaf block's bno */
69         xfs_dir2_block_t        *block;         /* block structure */
70         xfs_dir2_leaf_entry_t   *blp;           /* block's leaf entries */
71         xfs_dir2_block_tail_t   *btp;           /* block's tail */
72         xfs_inode_t             *dp;            /* incore directory inode */
73         int                     error;          /* error return code */
74         xfs_dabuf_t             *lbp;           /* leaf block's buffer */
75         xfs_dir2_db_t           ldb;            /* leaf block's bno */
76         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
77         xfs_dir2_leaf_tail_t    *ltp;           /* leaf's tail */
78         xfs_mount_t             *mp;            /* filesystem mount point */
79         int                     needlog;        /* need to log block header */
80         int                     needscan;       /* need to rescan bestfree */
81         xfs_trans_t             *tp;            /* transaction pointer */
82
83         xfs_dir2_trace_args_b("block_to_leaf", args, dbp);
84         dp = args->dp;
85         mp = dp->i_mount;
86         tp = args->trans;
87         /*
88          * Add the leaf block to the inode.
89          * This interface will only put blocks in the leaf/node range.
90          * Since that's empty now, we'll get the root (block 0 in range).
91          */
92         if ((error = xfs_da_grow_inode(args, &blkno))) {
93                 return error;
94         }
95         ldb = xfs_dir2_da_to_db(mp, blkno);
96         ASSERT(ldb == XFS_DIR2_LEAF_FIRSTDB(mp));
97         /*
98          * Initialize the leaf block, get a buffer for it.
99          */
100         if ((error = xfs_dir2_leaf_init(args, ldb, &lbp, XFS_DIR2_LEAF1_MAGIC))) {
101                 return error;
102         }
103         ASSERT(lbp != NULL);
104         leaf = lbp->data;
105         block = dbp->data;
106         xfs_dir2_data_check(dp, dbp);
107         btp = xfs_dir2_block_tail_p(mp, block);
108         blp = xfs_dir2_block_leaf_p(btp);
109         /*
110          * Set the counts in the leaf header.
111          */
112         leaf->hdr.count = cpu_to_be16(be32_to_cpu(btp->count));
113         leaf->hdr.stale = cpu_to_be16(be32_to_cpu(btp->stale));
114         /*
115          * Could compact these but I think we always do the conversion
116          * after squeezing out stale entries.
117          */
118         memcpy(leaf->ents, blp, be32_to_cpu(btp->count) * sizeof(xfs_dir2_leaf_entry_t));
119         xfs_dir2_leaf_log_ents(tp, lbp, 0, be16_to_cpu(leaf->hdr.count) - 1);
120         needscan = 0;
121         needlog = 1;
122         /*
123          * Make the space formerly occupied by the leaf entries and block
124          * tail be free.
125          */
126         xfs_dir2_data_make_free(tp, dbp,
127                 (xfs_dir2_data_aoff_t)((char *)blp - (char *)block),
128                 (xfs_dir2_data_aoff_t)((char *)block + mp->m_dirblksize -
129                                        (char *)blp),
130                 &needlog, &needscan);
131         /*
132          * Fix up the block header, make it a data block.
133          */
134         block->hdr.magic = cpu_to_be32(XFS_DIR2_DATA_MAGIC);
135         if (needscan)
136                 xfs_dir2_data_freescan(mp, (xfs_dir2_data_t *)block, &needlog);
137         /*
138          * Set up leaf tail and bests table.
139          */
140         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
141         ltp->bestcount = cpu_to_be32(1);
142         bestsp = xfs_dir2_leaf_bests_p(ltp);
143         bestsp[0] =  block->hdr.bestfree[0].length;
144         /*
145          * Log the data header and leaf bests table.
146          */
147         if (needlog)
148                 xfs_dir2_data_log_header(tp, dbp);
149         xfs_dir2_leaf_check(dp, lbp);
150         xfs_dir2_data_check(dp, dbp);
151         xfs_dir2_leaf_log_bests(tp, lbp, 0, 0);
152         xfs_da_buf_done(lbp);
153         return 0;
154 }
155
156 /*
157  * Add an entry to a leaf form directory.
158  */
159 int                                             /* error */
160 xfs_dir2_leaf_addname(
161         xfs_da_args_t           *args)          /* operation arguments */
162 {
163         __be16                  *bestsp;        /* freespace table in leaf */
164         int                     compact;        /* need to compact leaves */
165         xfs_dir2_data_t         *data;          /* data block structure */
166         xfs_dabuf_t             *dbp;           /* data block buffer */
167         xfs_dir2_data_entry_t   *dep;           /* data block entry */
168         xfs_inode_t             *dp;            /* incore directory inode */
169         xfs_dir2_data_unused_t  *dup;           /* data unused entry */
170         int                     error;          /* error return value */
171         int                     grown;          /* allocated new data block */
172         int                     highstale;      /* index of next stale leaf */
173         int                     i;              /* temporary, index */
174         int                     index;          /* leaf table position */
175         xfs_dabuf_t             *lbp;           /* leaf's buffer */
176         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
177         int                     length;         /* length of new entry */
178         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry table pointer */
179         int                     lfloglow;       /* low leaf logging index */
180         int                     lfloghigh;      /* high leaf logging index */
181         int                     lowstale;       /* index of prev stale leaf */
182         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail pointer */
183         xfs_mount_t             *mp;            /* filesystem mount point */
184         int                     needbytes;      /* leaf block bytes needed */
185         int                     needlog;        /* need to log data header */
186         int                     needscan;       /* need to rescan data free */
187         __be16                  *tagp;          /* end of data entry */
188         xfs_trans_t             *tp;            /* transaction pointer */
189         xfs_dir2_db_t           use_block;      /* data block number */
190
191         xfs_dir2_trace_args("leaf_addname", args);
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 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         xfs_ino_t               ino;
784
785         /*
786          * If the offset is at or past the largest allowed value,
787          * give up right away.
788          */
789         if (*offset >= XFS_DIR2_MAX_DATAPTR)
790                 return 0;
791
792         mp = dp->i_mount;
793
794         /*
795          * Set up to bmap a number of blocks based on the caller's
796          * buffer size, the directory block size, and the filesystem
797          * block size.
798          */
799         map_size = howmany(bufsize + mp->m_dirblksize, mp->m_sb.sb_blocksize);
800         map = kmem_alloc(map_size * sizeof(*map), KM_SLEEP);
801         map_valid = ra_index = ra_offset = ra_current = map_blocks = 0;
802         bp = NULL;
803
804         /*
805          * Inside the loop we keep the main offset value as a byte offset
806          * in the directory file.
807          */
808         curoff = xfs_dir2_dataptr_to_byte(mp, *offset);
809
810         /*
811          * Force this conversion through db so we truncate the offset
812          * down to get the start of the data block.
813          */
814         map_off = xfs_dir2_db_to_da(mp, xfs_dir2_byte_to_db(mp, curoff));
815         /*
816          * Loop over directory entries until we reach the end offset.
817          * Get more blocks and readahead as necessary.
818          */
819         while (curoff < XFS_DIR2_LEAF_OFFSET) {
820                 /*
821                  * If we have no buffer, or we're off the end of the
822                  * current buffer, need to get another one.
823                  */
824                 if (!bp || ptr >= (char *)bp->data + mp->m_dirblksize) {
825                         /*
826                          * If we have a buffer, we need to release it and
827                          * take it out of the mapping.
828                          */
829                         if (bp) {
830                                 xfs_da_brelse(NULL, bp);
831                                 bp = NULL;
832                                 map_blocks -= mp->m_dirblkfsbs;
833                                 /*
834                                  * Loop to get rid of the extents for the
835                                  * directory block.
836                                  */
837                                 for (i = mp->m_dirblkfsbs; i > 0; ) {
838                                         j = MIN((int)map->br_blockcount, i);
839                                         map->br_blockcount -= j;
840                                         map->br_startblock += j;
841                                         map->br_startoff += j;
842                                         /*
843                                          * If mapping is done, pitch it from
844                                          * the table.
845                                          */
846                                         if (!map->br_blockcount && --map_valid)
847                                                 memmove(&map[0], &map[1],
848                                                         sizeof(map[0]) *
849                                                         map_valid);
850                                         i -= j;
851                                 }
852                         }
853                         /*
854                          * Recalculate the readahead blocks wanted.
855                          */
856                         ra_want = howmany(bufsize + mp->m_dirblksize,
857                                           mp->m_sb.sb_blocksize) - 1;
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, 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                 /*
1080                  * Copy the entry into the putargs, and try formatting it.
1081                  */
1082                 dep = (xfs_dir2_data_entry_t *)ptr;
1083
1084                 length = xfs_dir2_data_entsize(dep->namelen);
1085
1086                 ino = be64_to_cpu(dep->inumber);
1087 #if XFS_BIG_INUMS
1088                 ino += mp->m_inoadd;
1089 #endif
1090
1091                 /*
1092                  * Won't fit.  Return to caller.
1093                  */
1094                 if (filldir(dirent, dep->name, dep->namelen,
1095                             xfs_dir2_byte_to_dataptr(mp, curoff) & 0x7fffffff,
1096                             ino, DT_UNKNOWN))
1097                         break;
1098
1099                 /*
1100                  * Advance to next entry in the block.
1101                  */
1102                 ptr += length;
1103                 curoff += length;
1104                 bufsize -= length;
1105         }
1106
1107         /*
1108          * All done.  Set output offset value to current offset.
1109          */
1110         if (curoff > xfs_dir2_dataptr_to_byte(mp, XFS_DIR2_MAX_DATAPTR))
1111                 *offset = XFS_DIR2_MAX_DATAPTR & 0x7fffffff;
1112         else
1113                 *offset = xfs_dir2_byte_to_dataptr(mp, curoff) & 0x7fffffff;
1114         kmem_free(map);
1115         if (bp)
1116                 xfs_da_brelse(NULL, bp);
1117         return error;
1118 }
1119
1120 /*
1121  * Initialize a new leaf block, leaf1 or leafn magic accepted.
1122  */
1123 int
1124 xfs_dir2_leaf_init(
1125         xfs_da_args_t           *args,          /* operation arguments */
1126         xfs_dir2_db_t           bno,            /* directory block number */
1127         xfs_dabuf_t             **bpp,          /* out: leaf buffer */
1128         int                     magic)          /* magic number for block */
1129 {
1130         xfs_dabuf_t             *bp;            /* leaf buffer */
1131         xfs_inode_t             *dp;            /* incore directory inode */
1132         int                     error;          /* error return code */
1133         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1134         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1135         xfs_mount_t             *mp;            /* filesystem mount point */
1136         xfs_trans_t             *tp;            /* transaction pointer */
1137
1138         dp = args->dp;
1139         ASSERT(dp != NULL);
1140         tp = args->trans;
1141         mp = dp->i_mount;
1142         ASSERT(bno >= XFS_DIR2_LEAF_FIRSTDB(mp) &&
1143                bno < XFS_DIR2_FREE_FIRSTDB(mp));
1144         /*
1145          * Get the buffer for the block.
1146          */
1147         error = xfs_da_get_buf(tp, dp, xfs_dir2_db_to_da(mp, bno), -1, &bp,
1148                 XFS_DATA_FORK);
1149         if (error) {
1150                 return error;
1151         }
1152         ASSERT(bp != NULL);
1153         leaf = bp->data;
1154         /*
1155          * Initialize the header.
1156          */
1157         leaf->hdr.info.magic = cpu_to_be16(magic);
1158         leaf->hdr.info.forw = 0;
1159         leaf->hdr.info.back = 0;
1160         leaf->hdr.count = 0;
1161         leaf->hdr.stale = 0;
1162         xfs_dir2_leaf_log_header(tp, bp);
1163         /*
1164          * If it's a leaf-format directory initialize the tail.
1165          * In this case our caller has the real bests table to copy into
1166          * the block.
1167          */
1168         if (magic == XFS_DIR2_LEAF1_MAGIC) {
1169                 ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1170                 ltp->bestcount = 0;
1171                 xfs_dir2_leaf_log_tail(tp, bp);
1172         }
1173         *bpp = bp;
1174         return 0;
1175 }
1176
1177 /*
1178  * Log the bests entries indicated from a leaf1 block.
1179  */
1180 static void
1181 xfs_dir2_leaf_log_bests(
1182         xfs_trans_t             *tp,            /* transaction pointer */
1183         xfs_dabuf_t             *bp,            /* leaf buffer */
1184         int                     first,          /* first entry to log */
1185         int                     last)           /* last entry to log */
1186 {
1187         __be16                  *firstb;        /* pointer to first entry */
1188         __be16                  *lastb;         /* pointer to last entry */
1189         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1190         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1191
1192         leaf = bp->data;
1193         ASSERT(be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAF1_MAGIC);
1194         ltp = xfs_dir2_leaf_tail_p(tp->t_mountp, leaf);
1195         firstb = xfs_dir2_leaf_bests_p(ltp) + first;
1196         lastb = xfs_dir2_leaf_bests_p(ltp) + last;
1197         xfs_da_log_buf(tp, bp, (uint)((char *)firstb - (char *)leaf),
1198                 (uint)((char *)lastb - (char *)leaf + sizeof(*lastb) - 1));
1199 }
1200
1201 /*
1202  * Log the leaf entries indicated from a leaf1 or leafn block.
1203  */
1204 void
1205 xfs_dir2_leaf_log_ents(
1206         xfs_trans_t             *tp,            /* transaction pointer */
1207         xfs_dabuf_t             *bp,            /* leaf buffer */
1208         int                     first,          /* first entry to log */
1209         int                     last)           /* last entry to log */
1210 {
1211         xfs_dir2_leaf_entry_t   *firstlep;      /* pointer to first entry */
1212         xfs_dir2_leaf_entry_t   *lastlep;       /* pointer to last entry */
1213         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1214
1215         leaf = bp->data;
1216         ASSERT(be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAF1_MAGIC ||
1217                be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAFN_MAGIC);
1218         firstlep = &leaf->ents[first];
1219         lastlep = &leaf->ents[last];
1220         xfs_da_log_buf(tp, bp, (uint)((char *)firstlep - (char *)leaf),
1221                 (uint)((char *)lastlep - (char *)leaf + sizeof(*lastlep) - 1));
1222 }
1223
1224 /*
1225  * Log the header of the leaf1 or leafn block.
1226  */
1227 void
1228 xfs_dir2_leaf_log_header(
1229         xfs_trans_t             *tp,            /* transaction pointer */
1230         xfs_dabuf_t             *bp)            /* leaf buffer */
1231 {
1232         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1233
1234         leaf = bp->data;
1235         ASSERT(be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAF1_MAGIC ||
1236                be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAFN_MAGIC);
1237         xfs_da_log_buf(tp, bp, (uint)((char *)&leaf->hdr - (char *)leaf),
1238                 (uint)(sizeof(leaf->hdr) - 1));
1239 }
1240
1241 /*
1242  * Log the tail of the leaf1 block.
1243  */
1244 STATIC void
1245 xfs_dir2_leaf_log_tail(
1246         xfs_trans_t             *tp,            /* transaction pointer */
1247         xfs_dabuf_t             *bp)            /* leaf buffer */
1248 {
1249         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1250         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1251         xfs_mount_t             *mp;            /* filesystem mount point */
1252
1253         mp = tp->t_mountp;
1254         leaf = bp->data;
1255         ASSERT(be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAF1_MAGIC);
1256         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1257         xfs_da_log_buf(tp, bp, (uint)((char *)ltp - (char *)leaf),
1258                 (uint)(mp->m_dirblksize - 1));
1259 }
1260
1261 /*
1262  * Look up the entry referred to by args in the leaf format directory.
1263  * Most of the work is done by the xfs_dir2_leaf_lookup_int routine which
1264  * is also used by the node-format code.
1265  */
1266 int
1267 xfs_dir2_leaf_lookup(
1268         xfs_da_args_t           *args)          /* operation arguments */
1269 {
1270         xfs_dabuf_t             *dbp;           /* data block buffer */
1271         xfs_dir2_data_entry_t   *dep;           /* data block entry */
1272         xfs_inode_t             *dp;            /* incore directory inode */
1273         int                     error;          /* error return code */
1274         int                     index;          /* found entry index */
1275         xfs_dabuf_t             *lbp;           /* leaf buffer */
1276         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1277         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1278         xfs_trans_t             *tp;            /* transaction pointer */
1279
1280         xfs_dir2_trace_args("leaf_lookup", args);
1281         /*
1282          * Look up name in the leaf block, returning both buffers and index.
1283          */
1284         if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1285                 return error;
1286         }
1287         tp = args->trans;
1288         dp = args->dp;
1289         xfs_dir2_leaf_check(dp, lbp);
1290         leaf = lbp->data;
1291         /*
1292          * Get to the leaf entry and contained data entry address.
1293          */
1294         lep = &leaf->ents[index];
1295         /*
1296          * Point to the data entry.
1297          */
1298         dep = (xfs_dir2_data_entry_t *)
1299               ((char *)dbp->data +
1300                xfs_dir2_dataptr_to_off(dp->i_mount, be32_to_cpu(lep->address)));
1301         /*
1302          * Return the found inode number & CI name if appropriate
1303          */
1304         args->inumber = be64_to_cpu(dep->inumber);
1305         error = xfs_dir_cilookup_result(args, dep->name, dep->namelen);
1306         xfs_da_brelse(tp, dbp);
1307         xfs_da_brelse(tp, lbp);
1308         return XFS_ERROR(error);
1309 }
1310
1311 /*
1312  * Look up name/hash in the leaf block.
1313  * Fill in indexp with the found index, and dbpp with the data buffer.
1314  * If not found dbpp will be NULL, and ENOENT comes back.
1315  * lbpp will always be filled in with the leaf buffer unless there's an error.
1316  */
1317 static int                                      /* error */
1318 xfs_dir2_leaf_lookup_int(
1319         xfs_da_args_t           *args,          /* operation arguments */
1320         xfs_dabuf_t             **lbpp,         /* out: leaf buffer */
1321         int                     *indexp,        /* out: index in leaf block */
1322         xfs_dabuf_t             **dbpp)         /* out: data buffer */
1323 {
1324         xfs_dir2_db_t           curdb = -1;     /* current data block number */
1325         xfs_dabuf_t             *dbp = NULL;    /* data buffer */
1326         xfs_dir2_data_entry_t   *dep;           /* data entry */
1327         xfs_inode_t             *dp;            /* incore directory inode */
1328         int                     error;          /* error return code */
1329         int                     index;          /* index in leaf block */
1330         xfs_dabuf_t             *lbp;           /* leaf buffer */
1331         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1332         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1333         xfs_mount_t             *mp;            /* filesystem mount point */
1334         xfs_dir2_db_t           newdb;          /* new data block number */
1335         xfs_trans_t             *tp;            /* transaction pointer */
1336         xfs_dir2_db_t           cidb = -1;      /* case match data block no. */
1337         enum xfs_dacmp          cmp;            /* name compare result */
1338
1339         dp = args->dp;
1340         tp = args->trans;
1341         mp = dp->i_mount;
1342         /*
1343          * Read the leaf block into the buffer.
1344          */
1345         error = xfs_da_read_buf(tp, dp, mp->m_dirleafblk, -1, &lbp,
1346                                                         XFS_DATA_FORK);
1347         if (error)
1348                 return error;
1349         *lbpp = lbp;
1350         leaf = lbp->data;
1351         xfs_dir2_leaf_check(dp, lbp);
1352         /*
1353          * Look for the first leaf entry with our hash value.
1354          */
1355         index = xfs_dir2_leaf_search_hash(args, lbp);
1356         /*
1357          * Loop over all the entries with the right hash value
1358          * looking to match the name.
1359          */
1360         for (lep = &leaf->ents[index]; index < be16_to_cpu(leaf->hdr.count) &&
1361                                 be32_to_cpu(lep->hashval) == args->hashval;
1362                                 lep++, index++) {
1363                 /*
1364                  * Skip over stale leaf entries.
1365                  */
1366                 if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
1367                         continue;
1368                 /*
1369                  * Get the new data block number.
1370                  */
1371                 newdb = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
1372                 /*
1373                  * If it's not the same as the old data block number,
1374                  * need to pitch the old one and read the new one.
1375                  */
1376                 if (newdb != curdb) {
1377                         if (dbp)
1378                                 xfs_da_brelse(tp, dbp);
1379                         error = xfs_da_read_buf(tp, dp,
1380                                                 xfs_dir2_db_to_da(mp, newdb),
1381                                                 -1, &dbp, XFS_DATA_FORK);
1382                         if (error) {
1383                                 xfs_da_brelse(tp, lbp);
1384                                 return error;
1385                         }
1386                         xfs_dir2_data_check(dp, dbp);
1387                         curdb = newdb;
1388                 }
1389                 /*
1390                  * Point to the data entry.
1391                  */
1392                 dep = (xfs_dir2_data_entry_t *)((char *)dbp->data +
1393                         xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address)));
1394                 /*
1395                  * Compare name and if it's an exact match, return the index
1396                  * and buffer. If it's the first case-insensitive match, store
1397                  * the index and buffer and continue looking for an exact match.
1398                  */
1399                 cmp = mp->m_dirnameops->compname(args, dep->name, dep->namelen);
1400                 if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) {
1401                         args->cmpresult = cmp;
1402                         *indexp = index;
1403                         /* case exact match: return the current buffer. */
1404                         if (cmp == XFS_CMP_EXACT) {
1405                                 *dbpp = dbp;
1406                                 return 0;
1407                         }
1408                         cidb = curdb;
1409                 }
1410         }
1411         ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
1412         /*
1413          * Here, we can only be doing a lookup (not a rename or remove).
1414          * If a case-insensitive match was found earlier, re-read the
1415          * appropriate data block if required and return it.
1416          */
1417         if (args->cmpresult == XFS_CMP_CASE) {
1418                 ASSERT(cidb != -1);
1419                 if (cidb != curdb) {
1420                         xfs_da_brelse(tp, dbp);
1421                         error = xfs_da_read_buf(tp, dp,
1422                                                 xfs_dir2_db_to_da(mp, cidb),
1423                                                 -1, &dbp, XFS_DATA_FORK);
1424                         if (error) {
1425                                 xfs_da_brelse(tp, lbp);
1426                                 return error;
1427                         }
1428                 }
1429                 *dbpp = dbp;
1430                 return 0;
1431         }
1432         /*
1433          * No match found, return ENOENT.
1434          */
1435         ASSERT(cidb == -1);
1436         if (dbp)
1437                 xfs_da_brelse(tp, dbp);
1438         xfs_da_brelse(tp, lbp);
1439         return XFS_ERROR(ENOENT);
1440 }
1441
1442 /*
1443  * Remove an entry from a leaf format directory.
1444  */
1445 int                                             /* error */
1446 xfs_dir2_leaf_removename(
1447         xfs_da_args_t           *args)          /* operation arguments */
1448 {
1449         __be16                  *bestsp;        /* leaf block best freespace */
1450         xfs_dir2_data_t         *data;          /* data block structure */
1451         xfs_dir2_db_t           db;             /* data block number */
1452         xfs_dabuf_t             *dbp;           /* data block buffer */
1453         xfs_dir2_data_entry_t   *dep;           /* data entry structure */
1454         xfs_inode_t             *dp;            /* incore directory inode */
1455         int                     error;          /* error return code */
1456         xfs_dir2_db_t           i;              /* temporary data block # */
1457         int                     index;          /* index into leaf entries */
1458         xfs_dabuf_t             *lbp;           /* leaf buffer */
1459         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1460         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1461         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1462         xfs_mount_t             *mp;            /* filesystem mount point */
1463         int                     needlog;        /* need to log data header */
1464         int                     needscan;       /* need to rescan data frees */
1465         xfs_dir2_data_off_t     oldbest;        /* old value of best free */
1466         xfs_trans_t             *tp;            /* transaction pointer */
1467
1468         xfs_dir2_trace_args("leaf_removename", args);
1469         /*
1470          * Lookup the leaf entry, get the leaf and data blocks read in.
1471          */
1472         if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1473                 return error;
1474         }
1475         dp = args->dp;
1476         tp = args->trans;
1477         mp = dp->i_mount;
1478         leaf = lbp->data;
1479         data = dbp->data;
1480         xfs_dir2_data_check(dp, dbp);
1481         /*
1482          * Point to the leaf entry, use that to point to the data entry.
1483          */
1484         lep = &leaf->ents[index];
1485         db = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
1486         dep = (xfs_dir2_data_entry_t *)
1487               ((char *)data + xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address)));
1488         needscan = needlog = 0;
1489         oldbest = be16_to_cpu(data->hdr.bestfree[0].length);
1490         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1491         bestsp = xfs_dir2_leaf_bests_p(ltp);
1492         ASSERT(be16_to_cpu(bestsp[db]) == oldbest);
1493         /*
1494          * Mark the former data entry unused.
1495          */
1496         xfs_dir2_data_make_free(tp, dbp,
1497                 (xfs_dir2_data_aoff_t)((char *)dep - (char *)data),
1498                 xfs_dir2_data_entsize(dep->namelen), &needlog, &needscan);
1499         /*
1500          * We just mark the leaf entry stale by putting a null in it.
1501          */
1502         be16_add_cpu(&leaf->hdr.stale, 1);
1503         xfs_dir2_leaf_log_header(tp, lbp);
1504         lep->address = cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
1505         xfs_dir2_leaf_log_ents(tp, lbp, index, index);
1506         /*
1507          * Scan the freespace in the data block again if necessary,
1508          * log the data block header if necessary.
1509          */
1510         if (needscan)
1511                 xfs_dir2_data_freescan(mp, data, &needlog);
1512         if (needlog)
1513                 xfs_dir2_data_log_header(tp, dbp);
1514         /*
1515          * If the longest freespace in the data block has changed,
1516          * put the new value in the bests table and log that.
1517          */
1518         if (be16_to_cpu(data->hdr.bestfree[0].length) != oldbest) {
1519                 bestsp[db] = data->hdr.bestfree[0].length;
1520                 xfs_dir2_leaf_log_bests(tp, lbp, db, db);
1521         }
1522         xfs_dir2_data_check(dp, dbp);
1523         /*
1524          * If the data block is now empty then get rid of the data block.
1525          */
1526         if (be16_to_cpu(data->hdr.bestfree[0].length) ==
1527             mp->m_dirblksize - (uint)sizeof(data->hdr)) {
1528                 ASSERT(db != mp->m_dirdatablk);
1529                 if ((error = xfs_dir2_shrink_inode(args, db, dbp))) {
1530                         /*
1531                          * Nope, can't get rid of it because it caused
1532                          * allocation of a bmap btree block to do so.
1533                          * Just go on, returning success, leaving the
1534                          * empty block in place.
1535                          */
1536                         if (error == ENOSPC && args->total == 0) {
1537                                 xfs_da_buf_done(dbp);
1538                                 error = 0;
1539                         }
1540                         xfs_dir2_leaf_check(dp, lbp);
1541                         xfs_da_buf_done(lbp);
1542                         return error;
1543                 }
1544                 dbp = NULL;
1545                 /*
1546                  * If this is the last data block then compact the
1547                  * bests table by getting rid of entries.
1548                  */
1549                 if (db == be32_to_cpu(ltp->bestcount) - 1) {
1550                         /*
1551                          * Look for the last active entry (i).
1552                          */
1553                         for (i = db - 1; i > 0; i--) {
1554                                 if (be16_to_cpu(bestsp[i]) != NULLDATAOFF)
1555                                         break;
1556                         }
1557                         /*
1558                          * Copy the table down so inactive entries at the
1559                          * end are removed.
1560                          */
1561                         memmove(&bestsp[db - i], bestsp,
1562                                 (be32_to_cpu(ltp->bestcount) - (db - i)) * sizeof(*bestsp));
1563                         be32_add_cpu(&ltp->bestcount, -(db - i));
1564                         xfs_dir2_leaf_log_tail(tp, lbp);
1565                         xfs_dir2_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1566                 } else
1567                         bestsp[db] = cpu_to_be16(NULLDATAOFF);
1568         }
1569         /*
1570          * If the data block was not the first one, drop it.
1571          */
1572         else if (db != mp->m_dirdatablk && dbp != NULL) {
1573                 xfs_da_buf_done(dbp);
1574                 dbp = NULL;
1575         }
1576         xfs_dir2_leaf_check(dp, lbp);
1577         /*
1578          * See if we can convert to block form.
1579          */
1580         return xfs_dir2_leaf_to_block(args, lbp, dbp);
1581 }
1582
1583 /*
1584  * Replace the inode number in a leaf format directory entry.
1585  */
1586 int                                             /* error */
1587 xfs_dir2_leaf_replace(
1588         xfs_da_args_t           *args)          /* operation arguments */
1589 {
1590         xfs_dabuf_t             *dbp;           /* data block buffer */
1591         xfs_dir2_data_entry_t   *dep;           /* data block entry */
1592         xfs_inode_t             *dp;            /* incore directory inode */
1593         int                     error;          /* error return code */
1594         int                     index;          /* index of leaf entry */
1595         xfs_dabuf_t             *lbp;           /* leaf buffer */
1596         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1597         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1598         xfs_trans_t             *tp;            /* transaction pointer */
1599
1600         xfs_dir2_trace_args("leaf_replace", args);
1601         /*
1602          * Look up the entry.
1603          */
1604         if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1605                 return error;
1606         }
1607         dp = args->dp;
1608         leaf = lbp->data;
1609         /*
1610          * Point to the leaf entry, get data address from it.
1611          */
1612         lep = &leaf->ents[index];
1613         /*
1614          * Point to the data entry.
1615          */
1616         dep = (xfs_dir2_data_entry_t *)
1617               ((char *)dbp->data +
1618                xfs_dir2_dataptr_to_off(dp->i_mount, be32_to_cpu(lep->address)));
1619         ASSERT(args->inumber != be64_to_cpu(dep->inumber));
1620         /*
1621          * Put the new inode number in, log it.
1622          */
1623         dep->inumber = cpu_to_be64(args->inumber);
1624         tp = args->trans;
1625         xfs_dir2_data_log_entry(tp, dbp, dep);
1626         xfs_da_buf_done(dbp);
1627         xfs_dir2_leaf_check(dp, lbp);
1628         xfs_da_brelse(tp, lbp);
1629         return 0;
1630 }
1631
1632 /*
1633  * Return index in the leaf block (lbp) which is either the first
1634  * one with this hash value, or if there are none, the insert point
1635  * for that hash value.
1636  */
1637 int                                             /* index value */
1638 xfs_dir2_leaf_search_hash(
1639         xfs_da_args_t           *args,          /* operation arguments */
1640         xfs_dabuf_t             *lbp)           /* leaf buffer */
1641 {
1642         xfs_dahash_t            hash=0;         /* hash from this entry */
1643         xfs_dahash_t            hashwant;       /* hash value looking for */
1644         int                     high;           /* high leaf index */
1645         int                     low;            /* low leaf index */
1646         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1647         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1648         int                     mid=0;          /* current leaf index */
1649
1650         leaf = lbp->data;
1651 #ifndef __KERNEL__
1652         if (!leaf->hdr.count)
1653                 return 0;
1654 #endif
1655         /*
1656          * Note, the table cannot be empty, so we have to go through the loop.
1657          * Binary search the leaf entries looking for our hash value.
1658          */
1659         for (lep = leaf->ents, low = 0, high = be16_to_cpu(leaf->hdr.count) - 1,
1660                 hashwant = args->hashval;
1661              low <= high; ) {
1662                 mid = (low + high) >> 1;
1663                 if ((hash = be32_to_cpu(lep[mid].hashval)) == hashwant)
1664                         break;
1665                 if (hash < hashwant)
1666                         low = mid + 1;
1667                 else
1668                         high = mid - 1;
1669         }
1670         /*
1671          * Found one, back up through all the equal hash values.
1672          */
1673         if (hash == hashwant) {
1674                 while (mid > 0 && be32_to_cpu(lep[mid - 1].hashval) == hashwant) {
1675                         mid--;
1676                 }
1677         }
1678         /*
1679          * Need to point to an entry higher than ours.
1680          */
1681         else if (hash < hashwant)
1682                 mid++;
1683         return mid;
1684 }
1685
1686 /*
1687  * Trim off a trailing data block.  We know it's empty since the leaf
1688  * freespace table says so.
1689  */
1690 int                                             /* error */
1691 xfs_dir2_leaf_trim_data(
1692         xfs_da_args_t           *args,          /* operation arguments */
1693         xfs_dabuf_t             *lbp,           /* leaf buffer */
1694         xfs_dir2_db_t           db)             /* data block number */
1695 {
1696         __be16                  *bestsp;        /* leaf bests table */
1697 #ifdef DEBUG
1698         xfs_dir2_data_t         *data;          /* data block structure */
1699 #endif
1700         xfs_dabuf_t             *dbp;           /* data block buffer */
1701         xfs_inode_t             *dp;            /* incore directory inode */
1702         int                     error;          /* error return value */
1703         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1704         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1705         xfs_mount_t             *mp;            /* filesystem mount point */
1706         xfs_trans_t             *tp;            /* transaction pointer */
1707
1708         dp = args->dp;
1709         mp = dp->i_mount;
1710         tp = args->trans;
1711         /*
1712          * Read the offending data block.  We need its buffer.
1713          */
1714         if ((error = xfs_da_read_buf(tp, dp, xfs_dir2_db_to_da(mp, db), -1, &dbp,
1715                         XFS_DATA_FORK))) {
1716                 return error;
1717         }
1718 #ifdef DEBUG
1719         data = dbp->data;
1720         ASSERT(be32_to_cpu(data->hdr.magic) == XFS_DIR2_DATA_MAGIC);
1721 #endif
1722         /* this seems to be an error
1723          * data is only valid if DEBUG is defined?
1724          * RMC 09/08/1999
1725          */
1726
1727         leaf = lbp->data;
1728         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1729         ASSERT(be16_to_cpu(data->hdr.bestfree[0].length) ==
1730                mp->m_dirblksize - (uint)sizeof(data->hdr));
1731         ASSERT(db == be32_to_cpu(ltp->bestcount) - 1);
1732         /*
1733          * Get rid of the data block.
1734          */
1735         if ((error = xfs_dir2_shrink_inode(args, db, dbp))) {
1736                 ASSERT(error != ENOSPC);
1737                 xfs_da_brelse(tp, dbp);
1738                 return error;
1739         }
1740         /*
1741          * Eliminate the last bests entry from the table.
1742          */
1743         bestsp = xfs_dir2_leaf_bests_p(ltp);
1744         be32_add_cpu(&ltp->bestcount, -1);
1745         memmove(&bestsp[1], &bestsp[0], be32_to_cpu(ltp->bestcount) * sizeof(*bestsp));
1746         xfs_dir2_leaf_log_tail(tp, lbp);
1747         xfs_dir2_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1748         return 0;
1749 }
1750
1751 /*
1752  * Convert node form directory to leaf form directory.
1753  * The root of the node form dir needs to already be a LEAFN block.
1754  * Just return if we can't do anything.
1755  */
1756 int                                             /* error */
1757 xfs_dir2_node_to_leaf(
1758         xfs_da_state_t          *state)         /* directory operation state */
1759 {
1760         xfs_da_args_t           *args;          /* operation arguments */
1761         xfs_inode_t             *dp;            /* incore directory inode */
1762         int                     error;          /* error return code */
1763         xfs_dabuf_t             *fbp;           /* buffer for freespace block */
1764         xfs_fileoff_t           fo;             /* freespace file offset */
1765         xfs_dir2_free_t         *free;          /* freespace structure */
1766         xfs_dabuf_t             *lbp;           /* buffer for leaf block */
1767         xfs_dir2_leaf_tail_t    *ltp;           /* tail of leaf structure */
1768         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1769         xfs_mount_t             *mp;            /* filesystem mount point */
1770         int                     rval;           /* successful free trim? */
1771         xfs_trans_t             *tp;            /* transaction pointer */
1772
1773         /*
1774          * There's more than a leaf level in the btree, so there must
1775          * be multiple leafn blocks.  Give up.
1776          */
1777         if (state->path.active > 1)
1778                 return 0;
1779         args = state->args;
1780         xfs_dir2_trace_args("node_to_leaf", args);
1781         mp = state->mp;
1782         dp = args->dp;
1783         tp = args->trans;
1784         /*
1785          * Get the last offset in the file.
1786          */
1787         if ((error = xfs_bmap_last_offset(tp, dp, &fo, XFS_DATA_FORK))) {
1788                 return error;
1789         }
1790         fo -= mp->m_dirblkfsbs;
1791         /*
1792          * If there are freespace blocks other than the first one,
1793          * take this opportunity to remove trailing empty freespace blocks
1794          * that may have been left behind during no-space-reservation
1795          * operations.
1796          */
1797         while (fo > mp->m_dirfreeblk) {
1798                 if ((error = xfs_dir2_node_trim_free(args, fo, &rval))) {
1799                         return error;
1800                 }
1801                 if (rval)
1802                         fo -= mp->m_dirblkfsbs;
1803                 else
1804                         return 0;
1805         }
1806         /*
1807          * Now find the block just before the freespace block.
1808          */
1809         if ((error = xfs_bmap_last_before(tp, dp, &fo, XFS_DATA_FORK))) {
1810                 return error;
1811         }
1812         /*
1813          * If it's not the single leaf block, give up.
1814          */
1815         if (XFS_FSB_TO_B(mp, fo) > XFS_DIR2_LEAF_OFFSET + mp->m_dirblksize)
1816                 return 0;
1817         lbp = state->path.blk[0].bp;
1818         leaf = lbp->data;
1819         ASSERT(be16_to_cpu(leaf->hdr.info.magic) == XFS_DIR2_LEAFN_MAGIC);
1820         /*
1821          * Read the freespace block.
1822          */
1823         if ((error = xfs_da_read_buf(tp, dp, mp->m_dirfreeblk, -1, &fbp,
1824                         XFS_DATA_FORK))) {
1825                 return error;
1826         }
1827         free = fbp->data;
1828         ASSERT(be32_to_cpu(free->hdr.magic) == XFS_DIR2_FREE_MAGIC);
1829         ASSERT(!free->hdr.firstdb);
1830         /*
1831          * Now see if the leafn and free data will fit in a leaf1.
1832          * If not, release the buffer and give up.
1833          */
1834         if ((uint)sizeof(leaf->hdr) +
1835             (be16_to_cpu(leaf->hdr.count) - be16_to_cpu(leaf->hdr.stale)) * (uint)sizeof(leaf->ents[0]) +
1836             be32_to_cpu(free->hdr.nvalid) * (uint)sizeof(leaf->bests[0]) +
1837             (uint)sizeof(leaf->tail) >
1838             mp->m_dirblksize) {
1839                 xfs_da_brelse(tp, fbp);
1840                 return 0;
1841         }
1842         /*
1843          * If the leaf has any stale entries in it, compress them out.
1844          * The compact routine will log the header.
1845          */
1846         if (be16_to_cpu(leaf->hdr.stale))
1847                 xfs_dir2_leaf_compact(args, lbp);
1848         else
1849                 xfs_dir2_leaf_log_header(tp, lbp);
1850         leaf->hdr.info.magic = cpu_to_be16(XFS_DIR2_LEAF1_MAGIC);
1851         /*
1852          * Set up the leaf tail from the freespace block.
1853          */
1854         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1855         ltp->bestcount = free->hdr.nvalid;
1856         /*
1857          * Set up the leaf bests table.
1858          */
1859         memcpy(xfs_dir2_leaf_bests_p(ltp), free->bests,
1860                 be32_to_cpu(ltp->bestcount) * sizeof(leaf->bests[0]));
1861         xfs_dir2_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1862         xfs_dir2_leaf_log_tail(tp, lbp);
1863         xfs_dir2_leaf_check(dp, lbp);
1864         /*
1865          * Get rid of the freespace block.
1866          */
1867         error = xfs_dir2_shrink_inode(args, XFS_DIR2_FREE_FIRSTDB(mp), fbp);
1868         if (error) {
1869                 /*
1870                  * This can't fail here because it can only happen when
1871                  * punching out the middle of an extent, and this is an
1872                  * isolated block.
1873                  */
1874                 ASSERT(error != ENOSPC);
1875                 return error;
1876         }
1877         fbp = NULL;
1878         /*
1879          * Now see if we can convert the single-leaf directory
1880          * down to a block form directory.
1881          * This routine always kills the dabuf for the leaf, so
1882          * eliminate it from the path.
1883          */
1884         error = xfs_dir2_leaf_to_block(args, lbp, NULL);
1885         state->path.blk[0].bp = NULL;
1886         return error;
1887 }