xfs: move getdents code into it's own file
[firefly-linux-kernel-4.4.55.git] / fs / xfs / xfs_dir2_leaf.c
1 /*
2  * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
3  * Copyright (c) 2013 Red Hat, Inc.
4  * All Rights Reserved.
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License as
8  * published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it would be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write the Free Software Foundation,
17  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
18  */
19 #include "xfs.h"
20 #include "xfs_fs.h"
21 #include "xfs_types.h"
22 #include "xfs_bit.h"
23 #include "xfs_log.h"
24 #include "xfs_trans.h"
25 #include "xfs_sb.h"
26 #include "xfs_ag.h"
27 #include "xfs_mount.h"
28 #include "xfs_da_btree.h"
29 #include "xfs_bmap_btree.h"
30 #include "xfs_dinode.h"
31 #include "xfs_inode.h"
32 #include "xfs_bmap.h"
33 #include "xfs_dir2_format.h"
34 #include "xfs_dir2_priv.h"
35 #include "xfs_error.h"
36 #include "xfs_trace.h"
37 #include "xfs_buf_item.h"
38 #include "xfs_cksum.h"
39
40 /*
41  * Local function declarations.
42  */
43 static int xfs_dir2_leaf_lookup_int(xfs_da_args_t *args, struct xfs_buf **lbpp,
44                                     int *indexp, struct xfs_buf **dbpp);
45 static void xfs_dir3_leaf_log_bests(struct xfs_trans *tp, struct xfs_buf *bp,
46                                     int first, int last);
47 static void xfs_dir3_leaf_log_tail(struct xfs_trans *tp, struct xfs_buf *bp);
48
49 /*
50  * Check the internal consistency of a leaf1 block.
51  * Pop an assert if something is wrong.
52  */
53 #ifdef DEBUG
54 #define xfs_dir3_leaf_check(mp, bp) \
55 do { \
56         if (!xfs_dir3_leaf1_check((mp), (bp))) \
57                 ASSERT(0); \
58 } while (0);
59
60 STATIC bool
61 xfs_dir3_leaf1_check(
62         struct xfs_mount        *mp,
63         struct xfs_buf          *bp)
64 {
65         struct xfs_dir2_leaf    *leaf = bp->b_addr;
66         struct xfs_dir3_icleaf_hdr leafhdr;
67
68         xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
69
70         if (leafhdr.magic == XFS_DIR3_LEAF1_MAGIC) {
71                 struct xfs_dir3_leaf_hdr *leaf3 = bp->b_addr;
72                 if (be64_to_cpu(leaf3->info.blkno) != bp->b_bn)
73                         return false;
74         } else if (leafhdr.magic != XFS_DIR2_LEAF1_MAGIC)
75                 return false;
76
77         return xfs_dir3_leaf_check_int(mp, &leafhdr, leaf);
78 }
79 #else
80 #define xfs_dir3_leaf_check(mp, bp)
81 #endif
82
83 void
84 xfs_dir3_leaf_hdr_from_disk(
85         struct xfs_dir3_icleaf_hdr      *to,
86         struct xfs_dir2_leaf            *from)
87 {
88         if (from->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
89             from->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC)) {
90                 to->forw = be32_to_cpu(from->hdr.info.forw);
91                 to->back = be32_to_cpu(from->hdr.info.back);
92                 to->magic = be16_to_cpu(from->hdr.info.magic);
93                 to->count = be16_to_cpu(from->hdr.count);
94                 to->stale = be16_to_cpu(from->hdr.stale);
95         } else {
96                 struct xfs_dir3_leaf_hdr *hdr3 = (struct xfs_dir3_leaf_hdr *)from;
97
98                 to->forw = be32_to_cpu(hdr3->info.hdr.forw);
99                 to->back = be32_to_cpu(hdr3->info.hdr.back);
100                 to->magic = be16_to_cpu(hdr3->info.hdr.magic);
101                 to->count = be16_to_cpu(hdr3->count);
102                 to->stale = be16_to_cpu(hdr3->stale);
103         }
104
105         ASSERT(to->magic == XFS_DIR2_LEAF1_MAGIC ||
106                to->magic == XFS_DIR3_LEAF1_MAGIC ||
107                to->magic == XFS_DIR2_LEAFN_MAGIC ||
108                to->magic == XFS_DIR3_LEAFN_MAGIC);
109 }
110
111 void
112 xfs_dir3_leaf_hdr_to_disk(
113         struct xfs_dir2_leaf            *to,
114         struct xfs_dir3_icleaf_hdr      *from)
115 {
116         ASSERT(from->magic == XFS_DIR2_LEAF1_MAGIC ||
117                from->magic == XFS_DIR3_LEAF1_MAGIC ||
118                from->magic == XFS_DIR2_LEAFN_MAGIC ||
119                from->magic == XFS_DIR3_LEAFN_MAGIC);
120
121         if (from->magic == XFS_DIR2_LEAF1_MAGIC ||
122             from->magic == XFS_DIR2_LEAFN_MAGIC) {
123                 to->hdr.info.forw = cpu_to_be32(from->forw);
124                 to->hdr.info.back = cpu_to_be32(from->back);
125                 to->hdr.info.magic = cpu_to_be16(from->magic);
126                 to->hdr.count = cpu_to_be16(from->count);
127                 to->hdr.stale = cpu_to_be16(from->stale);
128         } else {
129                 struct xfs_dir3_leaf_hdr *hdr3 = (struct xfs_dir3_leaf_hdr *)to;
130
131                 hdr3->info.hdr.forw = cpu_to_be32(from->forw);
132                 hdr3->info.hdr.back = cpu_to_be32(from->back);
133                 hdr3->info.hdr.magic = cpu_to_be16(from->magic);
134                 hdr3->count = cpu_to_be16(from->count);
135                 hdr3->stale = cpu_to_be16(from->stale);
136         }
137 }
138
139 bool
140 xfs_dir3_leaf_check_int(
141         struct xfs_mount        *mp,
142         struct xfs_dir3_icleaf_hdr *hdr,
143         struct xfs_dir2_leaf    *leaf)
144 {
145         struct xfs_dir2_leaf_entry *ents;
146         xfs_dir2_leaf_tail_t    *ltp;
147         int                     stale;
148         int                     i;
149
150         ents = xfs_dir3_leaf_ents_p(leaf);
151         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
152
153         /*
154          * XXX (dgc): This value is not restrictive enough.
155          * Should factor in the size of the bests table as well.
156          * We can deduce a value for that from di_size.
157          */
158         if (hdr->count > xfs_dir3_max_leaf_ents(mp, leaf))
159                 return false;
160
161         /* Leaves and bests don't overlap in leaf format. */
162         if ((hdr->magic == XFS_DIR2_LEAF1_MAGIC ||
163              hdr->magic == XFS_DIR3_LEAF1_MAGIC) &&
164             (char *)&ents[hdr->count] > (char *)xfs_dir2_leaf_bests_p(ltp))
165                 return false;
166
167         /* Check hash value order, count stale entries.  */
168         for (i = stale = 0; i < hdr->count; i++) {
169                 if (i + 1 < hdr->count) {
170                         if (be32_to_cpu(ents[i].hashval) >
171                                         be32_to_cpu(ents[i + 1].hashval))
172                                 return false;
173                 }
174                 if (ents[i].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
175                         stale++;
176         }
177         if (hdr->stale != stale)
178                 return false;
179         return true;
180 }
181
182 static bool
183 xfs_dir3_leaf_verify(
184         struct xfs_buf          *bp,
185         __uint16_t              magic)
186 {
187         struct xfs_mount        *mp = bp->b_target->bt_mount;
188         struct xfs_dir2_leaf    *leaf = bp->b_addr;
189         struct xfs_dir3_icleaf_hdr leafhdr;
190
191         ASSERT(magic == XFS_DIR2_LEAF1_MAGIC || magic == XFS_DIR2_LEAFN_MAGIC);
192
193         xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
194         if (xfs_sb_version_hascrc(&mp->m_sb)) {
195                 struct xfs_dir3_leaf_hdr *leaf3 = bp->b_addr;
196
197                 if ((magic == XFS_DIR2_LEAF1_MAGIC &&
198                      leafhdr.magic != XFS_DIR3_LEAF1_MAGIC) ||
199                     (magic == XFS_DIR2_LEAFN_MAGIC &&
200                      leafhdr.magic != XFS_DIR3_LEAFN_MAGIC))
201                         return false;
202
203                 if (!uuid_equal(&leaf3->info.uuid, &mp->m_sb.sb_uuid))
204                         return false;
205                 if (be64_to_cpu(leaf3->info.blkno) != bp->b_bn)
206                         return false;
207         } else {
208                 if (leafhdr.magic != magic)
209                         return false;
210         }
211         return xfs_dir3_leaf_check_int(mp, &leafhdr, leaf);
212 }
213
214 static void
215 __read_verify(
216         struct xfs_buf  *bp,
217         __uint16_t      magic)
218 {
219         struct xfs_mount        *mp = bp->b_target->bt_mount;
220
221         if ((xfs_sb_version_hascrc(&mp->m_sb) &&
222              !xfs_verify_cksum(bp->b_addr, BBTOB(bp->b_length),
223                                           XFS_DIR3_LEAF_CRC_OFF)) ||
224             !xfs_dir3_leaf_verify(bp, magic)) {
225                 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
226                 xfs_buf_ioerror(bp, EFSCORRUPTED);
227         }
228 }
229
230 static void
231 __write_verify(
232         struct xfs_buf  *bp,
233         __uint16_t      magic)
234 {
235         struct xfs_mount        *mp = bp->b_target->bt_mount;
236         struct xfs_buf_log_item *bip = bp->b_fspriv;
237         struct xfs_dir3_leaf_hdr *hdr3 = bp->b_addr;
238
239         if (!xfs_dir3_leaf_verify(bp, magic)) {
240                 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
241                 xfs_buf_ioerror(bp, EFSCORRUPTED);
242                 return;
243         }
244
245         if (!xfs_sb_version_hascrc(&mp->m_sb))
246                 return;
247
248         if (bip)
249                 hdr3->info.lsn = cpu_to_be64(bip->bli_item.li_lsn);
250
251         xfs_update_cksum(bp->b_addr, BBTOB(bp->b_length), XFS_DIR3_LEAF_CRC_OFF);
252 }
253
254 static void
255 xfs_dir3_leaf1_read_verify(
256         struct xfs_buf  *bp)
257 {
258         __read_verify(bp, XFS_DIR2_LEAF1_MAGIC);
259 }
260
261 static void
262 xfs_dir3_leaf1_write_verify(
263         struct xfs_buf  *bp)
264 {
265         __write_verify(bp, XFS_DIR2_LEAF1_MAGIC);
266 }
267
268 static void
269 xfs_dir3_leafn_read_verify(
270         struct xfs_buf  *bp)
271 {
272         __read_verify(bp, XFS_DIR2_LEAFN_MAGIC);
273 }
274
275 static void
276 xfs_dir3_leafn_write_verify(
277         struct xfs_buf  *bp)
278 {
279         __write_verify(bp, XFS_DIR2_LEAFN_MAGIC);
280 }
281
282 const struct xfs_buf_ops xfs_dir3_leaf1_buf_ops = {
283         .verify_read = xfs_dir3_leaf1_read_verify,
284         .verify_write = xfs_dir3_leaf1_write_verify,
285 };
286
287 const struct xfs_buf_ops xfs_dir3_leafn_buf_ops = {
288         .verify_read = xfs_dir3_leafn_read_verify,
289         .verify_write = xfs_dir3_leafn_write_verify,
290 };
291
292 static int
293 xfs_dir3_leaf_read(
294         struct xfs_trans        *tp,
295         struct xfs_inode        *dp,
296         xfs_dablk_t             fbno,
297         xfs_daddr_t             mappedbno,
298         struct xfs_buf          **bpp)
299 {
300         int                     err;
301
302         err = xfs_da_read_buf(tp, dp, fbno, mappedbno, bpp,
303                                 XFS_DATA_FORK, &xfs_dir3_leaf1_buf_ops);
304         if (!err && tp)
305                 xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_LEAF1_BUF);
306         return err;
307 }
308
309 int
310 xfs_dir3_leafn_read(
311         struct xfs_trans        *tp,
312         struct xfs_inode        *dp,
313         xfs_dablk_t             fbno,
314         xfs_daddr_t             mappedbno,
315         struct xfs_buf          **bpp)
316 {
317         int                     err;
318
319         err = xfs_da_read_buf(tp, dp, fbno, mappedbno, bpp,
320                                 XFS_DATA_FORK, &xfs_dir3_leafn_buf_ops);
321         if (!err && tp)
322                 xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_DIR_LEAFN_BUF);
323         return err;
324 }
325
326 /*
327  * Initialize a new leaf block, leaf1 or leafn magic accepted.
328  */
329 static void
330 xfs_dir3_leaf_init(
331         struct xfs_mount        *mp,
332         struct xfs_trans        *tp,
333         struct xfs_buf          *bp,
334         xfs_ino_t               owner,
335         __uint16_t              type)
336 {
337         struct xfs_dir2_leaf    *leaf = bp->b_addr;
338
339         ASSERT(type == XFS_DIR2_LEAF1_MAGIC || type == XFS_DIR2_LEAFN_MAGIC);
340
341         if (xfs_sb_version_hascrc(&mp->m_sb)) {
342                 struct xfs_dir3_leaf_hdr *leaf3 = bp->b_addr;
343
344                 memset(leaf3, 0, sizeof(*leaf3));
345
346                 leaf3->info.hdr.magic = (type == XFS_DIR2_LEAF1_MAGIC)
347                                          ? cpu_to_be16(XFS_DIR3_LEAF1_MAGIC)
348                                          : cpu_to_be16(XFS_DIR3_LEAFN_MAGIC);
349                 leaf3->info.blkno = cpu_to_be64(bp->b_bn);
350                 leaf3->info.owner = cpu_to_be64(owner);
351                 uuid_copy(&leaf3->info.uuid, &mp->m_sb.sb_uuid);
352         } else {
353                 memset(leaf, 0, sizeof(*leaf));
354                 leaf->hdr.info.magic = cpu_to_be16(type);
355         }
356
357         /*
358          * If it's a leaf-format directory initialize the tail.
359          * Caller is responsible for initialising the bests table.
360          */
361         if (type == XFS_DIR2_LEAF1_MAGIC) {
362                 struct xfs_dir2_leaf_tail *ltp;
363
364                 ltp = xfs_dir2_leaf_tail_p(mp, leaf);
365                 ltp->bestcount = 0;
366                 bp->b_ops = &xfs_dir3_leaf1_buf_ops;
367                 xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_LEAF1_BUF);
368         } else {
369                 bp->b_ops = &xfs_dir3_leafn_buf_ops;
370                 xfs_trans_buf_set_type(tp, bp, XFS_BLFT_DIR_LEAFN_BUF);
371         }
372 }
373
374 int
375 xfs_dir3_leaf_get_buf(
376         xfs_da_args_t           *args,
377         xfs_dir2_db_t           bno,
378         struct xfs_buf          **bpp,
379         __uint16_t              magic)
380 {
381         struct xfs_inode        *dp = args->dp;
382         struct xfs_trans        *tp = args->trans;
383         struct xfs_mount        *mp = dp->i_mount;
384         struct xfs_buf          *bp;
385         int                     error;
386
387         ASSERT(magic == XFS_DIR2_LEAF1_MAGIC || magic == XFS_DIR2_LEAFN_MAGIC);
388         ASSERT(bno >= XFS_DIR2_LEAF_FIRSTDB(mp) &&
389                bno < XFS_DIR2_FREE_FIRSTDB(mp));
390
391         error = xfs_da_get_buf(tp, dp, xfs_dir2_db_to_da(mp, bno), -1, &bp,
392                                XFS_DATA_FORK);
393         if (error)
394                 return error;
395
396         xfs_dir3_leaf_init(mp, tp, bp, dp->i_ino, magic);
397         xfs_dir3_leaf_log_header(tp, bp);
398         if (magic == XFS_DIR2_LEAF1_MAGIC)
399                 xfs_dir3_leaf_log_tail(tp, bp);
400         *bpp = bp;
401         return 0;
402 }
403
404 /*
405  * Convert a block form directory to a leaf form directory.
406  */
407 int                                             /* error */
408 xfs_dir2_block_to_leaf(
409         xfs_da_args_t           *args,          /* operation arguments */
410         struct xfs_buf          *dbp)           /* input block's buffer */
411 {
412         __be16                  *bestsp;        /* leaf's bestsp entries */
413         xfs_dablk_t             blkno;          /* leaf block's bno */
414         xfs_dir2_data_hdr_t     *hdr;           /* block header */
415         xfs_dir2_leaf_entry_t   *blp;           /* block's leaf entries */
416         xfs_dir2_block_tail_t   *btp;           /* block's tail */
417         xfs_inode_t             *dp;            /* incore directory inode */
418         int                     error;          /* error return code */
419         struct xfs_buf          *lbp;           /* leaf block's buffer */
420         xfs_dir2_db_t           ldb;            /* leaf block's bno */
421         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
422         xfs_dir2_leaf_tail_t    *ltp;           /* leaf's tail */
423         xfs_mount_t             *mp;            /* filesystem mount point */
424         int                     needlog;        /* need to log block header */
425         int                     needscan;       /* need to rescan bestfree */
426         xfs_trans_t             *tp;            /* transaction pointer */
427         struct xfs_dir2_data_free *bf;
428         struct xfs_dir2_leaf_entry *ents;
429         struct xfs_dir3_icleaf_hdr leafhdr;
430
431         trace_xfs_dir2_block_to_leaf(args);
432
433         dp = args->dp;
434         mp = dp->i_mount;
435         tp = args->trans;
436         /*
437          * Add the leaf block to the inode.
438          * This interface will only put blocks in the leaf/node range.
439          * Since that's empty now, we'll get the root (block 0 in range).
440          */
441         if ((error = xfs_da_grow_inode(args, &blkno))) {
442                 return error;
443         }
444         ldb = xfs_dir2_da_to_db(mp, blkno);
445         ASSERT(ldb == XFS_DIR2_LEAF_FIRSTDB(mp));
446         /*
447          * Initialize the leaf block, get a buffer for it.
448          */
449         error = xfs_dir3_leaf_get_buf(args, ldb, &lbp, XFS_DIR2_LEAF1_MAGIC);
450         if (error)
451                 return error;
452
453         leaf = lbp->b_addr;
454         hdr = dbp->b_addr;
455         xfs_dir3_data_check(dp, dbp);
456         btp = xfs_dir2_block_tail_p(mp, hdr);
457         blp = xfs_dir2_block_leaf_p(btp);
458         bf = xfs_dir3_data_bestfree_p(hdr);
459         ents = xfs_dir3_leaf_ents_p(leaf);
460
461         /*
462          * Set the counts in the leaf header.
463          */
464         xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
465         leafhdr.count = be32_to_cpu(btp->count);
466         leafhdr.stale = be32_to_cpu(btp->stale);
467         xfs_dir3_leaf_hdr_to_disk(leaf, &leafhdr);
468         xfs_dir3_leaf_log_header(tp, lbp);
469
470         /*
471          * Could compact these but I think we always do the conversion
472          * after squeezing out stale entries.
473          */
474         memcpy(ents, blp, be32_to_cpu(btp->count) * sizeof(xfs_dir2_leaf_entry_t));
475         xfs_dir3_leaf_log_ents(tp, lbp, 0, leafhdr.count - 1);
476         needscan = 0;
477         needlog = 1;
478         /*
479          * Make the space formerly occupied by the leaf entries and block
480          * tail be free.
481          */
482         xfs_dir2_data_make_free(tp, dbp,
483                 (xfs_dir2_data_aoff_t)((char *)blp - (char *)hdr),
484                 (xfs_dir2_data_aoff_t)((char *)hdr + mp->m_dirblksize -
485                                        (char *)blp),
486                 &needlog, &needscan);
487         /*
488          * Fix up the block header, make it a data block.
489          */
490         dbp->b_ops = &xfs_dir3_data_buf_ops;
491         xfs_trans_buf_set_type(tp, dbp, XFS_BLFT_DIR_DATA_BUF);
492         if (hdr->magic == cpu_to_be32(XFS_DIR2_BLOCK_MAGIC))
493                 hdr->magic = cpu_to_be32(XFS_DIR2_DATA_MAGIC);
494         else
495                 hdr->magic = cpu_to_be32(XFS_DIR3_DATA_MAGIC);
496
497         if (needscan)
498                 xfs_dir2_data_freescan(mp, hdr, &needlog);
499         /*
500          * Set up leaf tail and bests table.
501          */
502         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
503         ltp->bestcount = cpu_to_be32(1);
504         bestsp = xfs_dir2_leaf_bests_p(ltp);
505         bestsp[0] =  bf[0].length;
506         /*
507          * Log the data header and leaf bests table.
508          */
509         if (needlog)
510                 xfs_dir2_data_log_header(tp, dbp);
511         xfs_dir3_leaf_check(mp, lbp);
512         xfs_dir3_data_check(dp, dbp);
513         xfs_dir3_leaf_log_bests(tp, lbp, 0, 0);
514         return 0;
515 }
516
517 STATIC void
518 xfs_dir3_leaf_find_stale(
519         struct xfs_dir3_icleaf_hdr *leafhdr,
520         struct xfs_dir2_leaf_entry *ents,
521         int                     index,
522         int                     *lowstale,
523         int                     *highstale)
524 {
525         /*
526          * Find the first stale entry before our index, if any.
527          */
528         for (*lowstale = index - 1; *lowstale >= 0; --*lowstale) {
529                 if (ents[*lowstale].address ==
530                     cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
531                         break;
532         }
533
534         /*
535          * Find the first stale entry at or after our index, if any.
536          * Stop if the result would require moving more entries than using
537          * lowstale.
538          */
539         for (*highstale = index; *highstale < leafhdr->count; ++*highstale) {
540                 if (ents[*highstale].address ==
541                     cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
542                         break;
543                 if (*lowstale >= 0 && index - *lowstale <= *highstale - index)
544                         break;
545         }
546 }
547
548 struct xfs_dir2_leaf_entry *
549 xfs_dir3_leaf_find_entry(
550         struct xfs_dir3_icleaf_hdr *leafhdr,
551         struct xfs_dir2_leaf_entry *ents,
552         int                     index,          /* leaf table position */
553         int                     compact,        /* need to compact leaves */
554         int                     lowstale,       /* index of prev stale leaf */
555         int                     highstale,      /* index of next stale leaf */
556         int                     *lfloglow,      /* low leaf logging index */
557         int                     *lfloghigh)     /* high leaf logging index */
558 {
559         if (!leafhdr->stale) {
560                 xfs_dir2_leaf_entry_t   *lep;   /* leaf entry table pointer */
561
562                 /*
563                  * Now we need to make room to insert the leaf entry.
564                  *
565                  * If there are no stale entries, just insert a hole at index.
566                  */
567                 lep = &ents[index];
568                 if (index < leafhdr->count)
569                         memmove(lep + 1, lep,
570                                 (leafhdr->count - index) * sizeof(*lep));
571
572                 /*
573                  * Record low and high logging indices for the leaf.
574                  */
575                 *lfloglow = index;
576                 *lfloghigh = leafhdr->count++;
577                 return lep;
578         }
579
580         /*
581          * There are stale entries.
582          *
583          * We will use one of them for the new entry.  It's probably not at
584          * the right location, so we'll have to shift some up or down first.
585          *
586          * If we didn't compact before, we need to find the nearest stale
587          * entries before and after our insertion point.
588          */
589         if (compact == 0)
590                 xfs_dir3_leaf_find_stale(leafhdr, ents, index,
591                                          &lowstale, &highstale);
592
593         /*
594          * If the low one is better, use it.
595          */
596         if (lowstale >= 0 &&
597             (highstale == leafhdr->count ||
598              index - lowstale - 1 < highstale - index)) {
599                 ASSERT(index - lowstale - 1 >= 0);
600                 ASSERT(ents[lowstale].address ==
601                        cpu_to_be32(XFS_DIR2_NULL_DATAPTR));
602
603                 /*
604                  * Copy entries up to cover the stale entry and make room
605                  * for the new entry.
606                  */
607                 if (index - lowstale - 1 > 0) {
608                         memmove(&ents[lowstale], &ents[lowstale + 1],
609                                 (index - lowstale - 1) *
610                                         sizeof(xfs_dir2_leaf_entry_t));
611                 }
612                 *lfloglow = MIN(lowstale, *lfloglow);
613                 *lfloghigh = MAX(index - 1, *lfloghigh);
614                 leafhdr->stale--;
615                 return &ents[index - 1];
616         }
617
618         /*
619          * The high one is better, so use that one.
620          */
621         ASSERT(highstale - index >= 0);
622         ASSERT(ents[highstale].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR));
623
624         /*
625          * Copy entries down to cover the stale entry and make room for the
626          * new entry.
627          */
628         if (highstale - index > 0) {
629                 memmove(&ents[index + 1], &ents[index],
630                         (highstale - index) * sizeof(xfs_dir2_leaf_entry_t));
631         }
632         *lfloglow = MIN(index, *lfloglow);
633         *lfloghigh = MAX(highstale, *lfloghigh);
634         leafhdr->stale--;
635         return &ents[index];
636 }
637
638 /*
639  * Add an entry to a leaf form directory.
640  */
641 int                                             /* error */
642 xfs_dir2_leaf_addname(
643         xfs_da_args_t           *args)          /* operation arguments */
644 {
645         __be16                  *bestsp;        /* freespace table in leaf */
646         int                     compact;        /* need to compact leaves */
647         xfs_dir2_data_hdr_t     *hdr;           /* data block header */
648         struct xfs_buf          *dbp;           /* data block buffer */
649         xfs_dir2_data_entry_t   *dep;           /* data block entry */
650         xfs_inode_t             *dp;            /* incore directory inode */
651         xfs_dir2_data_unused_t  *dup;           /* data unused entry */
652         int                     error;          /* error return value */
653         int                     grown;          /* allocated new data block */
654         int                     highstale;      /* index of next stale leaf */
655         int                     i;              /* temporary, index */
656         int                     index;          /* leaf table position */
657         struct xfs_buf          *lbp;           /* leaf's buffer */
658         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
659         int                     length;         /* length of new entry */
660         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry table pointer */
661         int                     lfloglow;       /* low leaf logging index */
662         int                     lfloghigh;      /* high leaf logging index */
663         int                     lowstale;       /* index of prev stale leaf */
664         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail pointer */
665         xfs_mount_t             *mp;            /* filesystem mount point */
666         int                     needbytes;      /* leaf block bytes needed */
667         int                     needlog;        /* need to log data header */
668         int                     needscan;       /* need to rescan data free */
669         __be16                  *tagp;          /* end of data entry */
670         xfs_trans_t             *tp;            /* transaction pointer */
671         xfs_dir2_db_t           use_block;      /* data block number */
672         struct xfs_dir2_data_free *bf;          /* bestfree table */
673         struct xfs_dir2_leaf_entry *ents;
674         struct xfs_dir3_icleaf_hdr leafhdr;
675
676         trace_xfs_dir2_leaf_addname(args);
677
678         dp = args->dp;
679         tp = args->trans;
680         mp = dp->i_mount;
681
682         error = xfs_dir3_leaf_read(tp, dp, mp->m_dirleafblk, -1, &lbp);
683         if (error)
684                 return error;
685
686         /*
687          * Look up the entry by hash value and name.
688          * We know it's not there, our caller has already done a lookup.
689          * So the index is of the entry to insert in front of.
690          * But if there are dup hash values the index is of the first of those.
691          */
692         index = xfs_dir2_leaf_search_hash(args, lbp);
693         leaf = lbp->b_addr;
694         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
695         ents = xfs_dir3_leaf_ents_p(leaf);
696         xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
697         bestsp = xfs_dir2_leaf_bests_p(ltp);
698         length = xfs_dir2_data_entsize(args->namelen);
699
700         /*
701          * See if there are any entries with the same hash value
702          * and space in their block for the new entry.
703          * This is good because it puts multiple same-hash value entries
704          * in a data block, improving the lookup of those entries.
705          */
706         for (use_block = -1, lep = &ents[index];
707              index < leafhdr.count && be32_to_cpu(lep->hashval) == args->hashval;
708              index++, lep++) {
709                 if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
710                         continue;
711                 i = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
712                 ASSERT(i < be32_to_cpu(ltp->bestcount));
713                 ASSERT(bestsp[i] != cpu_to_be16(NULLDATAOFF));
714                 if (be16_to_cpu(bestsp[i]) >= length) {
715                         use_block = i;
716                         break;
717                 }
718         }
719         /*
720          * Didn't find a block yet, linear search all the data blocks.
721          */
722         if (use_block == -1) {
723                 for (i = 0; i < be32_to_cpu(ltp->bestcount); i++) {
724                         /*
725                          * Remember a block we see that's missing.
726                          */
727                         if (bestsp[i] == cpu_to_be16(NULLDATAOFF) &&
728                             use_block == -1)
729                                 use_block = i;
730                         else if (be16_to_cpu(bestsp[i]) >= length) {
731                                 use_block = i;
732                                 break;
733                         }
734                 }
735         }
736         /*
737          * How many bytes do we need in the leaf block?
738          */
739         needbytes = 0;
740         if (!leafhdr.stale)
741                 needbytes += sizeof(xfs_dir2_leaf_entry_t);
742         if (use_block == -1)
743                 needbytes += sizeof(xfs_dir2_data_off_t);
744
745         /*
746          * Now kill use_block if it refers to a missing block, so we
747          * can use it as an indication of allocation needed.
748          */
749         if (use_block != -1 && bestsp[use_block] == cpu_to_be16(NULLDATAOFF))
750                 use_block = -1;
751         /*
752          * If we don't have enough free bytes but we can make enough
753          * by compacting out stale entries, we'll do that.
754          */
755         if ((char *)bestsp - (char *)&ents[leafhdr.count] < needbytes &&
756             leafhdr.stale > 1)
757                 compact = 1;
758
759         /*
760          * Otherwise if we don't have enough free bytes we need to
761          * convert to node form.
762          */
763         else if ((char *)bestsp - (char *)&ents[leafhdr.count] < needbytes) {
764                 /*
765                  * Just checking or no space reservation, give up.
766                  */
767                 if ((args->op_flags & XFS_DA_OP_JUSTCHECK) ||
768                                                         args->total == 0) {
769                         xfs_trans_brelse(tp, lbp);
770                         return XFS_ERROR(ENOSPC);
771                 }
772                 /*
773                  * Convert to node form.
774                  */
775                 error = xfs_dir2_leaf_to_node(args, lbp);
776                 if (error)
777                         return error;
778                 /*
779                  * Then add the new entry.
780                  */
781                 return xfs_dir2_node_addname(args);
782         }
783         /*
784          * Otherwise it will fit without compaction.
785          */
786         else
787                 compact = 0;
788         /*
789          * If just checking, then it will fit unless we needed to allocate
790          * a new data block.
791          */
792         if (args->op_flags & XFS_DA_OP_JUSTCHECK) {
793                 xfs_trans_brelse(tp, lbp);
794                 return use_block == -1 ? XFS_ERROR(ENOSPC) : 0;
795         }
796         /*
797          * If no allocations are allowed, return now before we've
798          * changed anything.
799          */
800         if (args->total == 0 && use_block == -1) {
801                 xfs_trans_brelse(tp, lbp);
802                 return XFS_ERROR(ENOSPC);
803         }
804         /*
805          * Need to compact the leaf entries, removing stale ones.
806          * Leave one stale entry behind - the one closest to our
807          * insertion index - and we'll shift that one to our insertion
808          * point later.
809          */
810         if (compact) {
811                 xfs_dir3_leaf_compact_x1(&leafhdr, ents, &index, &lowstale,
812                         &highstale, &lfloglow, &lfloghigh);
813         }
814         /*
815          * There are stale entries, so we'll need log-low and log-high
816          * impossibly bad values later.
817          */
818         else if (leafhdr.stale) {
819                 lfloglow = leafhdr.count;
820                 lfloghigh = -1;
821         }
822         /*
823          * If there was no data block space found, we need to allocate
824          * a new one.
825          */
826         if (use_block == -1) {
827                 /*
828                  * Add the new data block.
829                  */
830                 if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_DATA_SPACE,
831                                 &use_block))) {
832                         xfs_trans_brelse(tp, lbp);
833                         return error;
834                 }
835                 /*
836                  * Initialize the block.
837                  */
838                 if ((error = xfs_dir3_data_init(args, use_block, &dbp))) {
839                         xfs_trans_brelse(tp, lbp);
840                         return error;
841                 }
842                 /*
843                  * If we're adding a new data block on the end we need to
844                  * extend the bests table.  Copy it up one entry.
845                  */
846                 if (use_block >= be32_to_cpu(ltp->bestcount)) {
847                         bestsp--;
848                         memmove(&bestsp[0], &bestsp[1],
849                                 be32_to_cpu(ltp->bestcount) * sizeof(bestsp[0]));
850                         be32_add_cpu(&ltp->bestcount, 1);
851                         xfs_dir3_leaf_log_tail(tp, lbp);
852                         xfs_dir3_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
853                 }
854                 /*
855                  * If we're filling in a previously empty block just log it.
856                  */
857                 else
858                         xfs_dir3_leaf_log_bests(tp, lbp, use_block, use_block);
859                 hdr = dbp->b_addr;
860                 bf = xfs_dir3_data_bestfree_p(hdr);
861                 bestsp[use_block] = bf[0].length;
862                 grown = 1;
863         } else {
864                 /*
865                  * Already had space in some data block.
866                  * Just read that one in.
867                  */
868                 error = xfs_dir3_data_read(tp, dp,
869                                            xfs_dir2_db_to_da(mp, use_block),
870                                            -1, &dbp);
871                 if (error) {
872                         xfs_trans_brelse(tp, lbp);
873                         return error;
874                 }
875                 hdr = dbp->b_addr;
876                 bf = xfs_dir3_data_bestfree_p(hdr);
877                 grown = 0;
878         }
879         /*
880          * Point to the biggest freespace in our data block.
881          */
882         dup = (xfs_dir2_data_unused_t *)
883               ((char *)hdr + be16_to_cpu(bf[0].offset));
884         ASSERT(be16_to_cpu(dup->length) >= length);
885         needscan = needlog = 0;
886         /*
887          * Mark the initial part of our freespace in use for the new entry.
888          */
889         xfs_dir2_data_use_free(tp, dbp, dup,
890                 (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr), length,
891                 &needlog, &needscan);
892         /*
893          * Initialize our new entry (at last).
894          */
895         dep = (xfs_dir2_data_entry_t *)dup;
896         dep->inumber = cpu_to_be64(args->inumber);
897         dep->namelen = args->namelen;
898         memcpy(dep->name, args->name, dep->namelen);
899         tagp = xfs_dir2_data_entry_tag_p(dep);
900         *tagp = cpu_to_be16((char *)dep - (char *)hdr);
901         /*
902          * Need to scan fix up the bestfree table.
903          */
904         if (needscan)
905                 xfs_dir2_data_freescan(mp, hdr, &needlog);
906         /*
907          * Need to log the data block's header.
908          */
909         if (needlog)
910                 xfs_dir2_data_log_header(tp, dbp);
911         xfs_dir2_data_log_entry(tp, dbp, dep);
912         /*
913          * If the bests table needs to be changed, do it.
914          * Log the change unless we've already done that.
915          */
916         if (be16_to_cpu(bestsp[use_block]) != be16_to_cpu(bf[0].length)) {
917                 bestsp[use_block] = bf[0].length;
918                 if (!grown)
919                         xfs_dir3_leaf_log_bests(tp, lbp, use_block, use_block);
920         }
921
922         lep = xfs_dir3_leaf_find_entry(&leafhdr, ents, index, compact, lowstale,
923                                        highstale, &lfloglow, &lfloghigh);
924
925         /*
926          * Fill in the new leaf entry.
927          */
928         lep->hashval = cpu_to_be32(args->hashval);
929         lep->address = cpu_to_be32(xfs_dir2_db_off_to_dataptr(mp, use_block,
930                                 be16_to_cpu(*tagp)));
931         /*
932          * Log the leaf fields and give up the buffers.
933          */
934         xfs_dir3_leaf_hdr_to_disk(leaf, &leafhdr);
935         xfs_dir3_leaf_log_header(tp, lbp);
936         xfs_dir3_leaf_log_ents(tp, lbp, lfloglow, lfloghigh);
937         xfs_dir3_leaf_check(mp, lbp);
938         xfs_dir3_data_check(dp, dbp);
939         return 0;
940 }
941
942 /*
943  * Compact out any stale entries in the leaf.
944  * Log the header and changed leaf entries, if any.
945  */
946 void
947 xfs_dir3_leaf_compact(
948         xfs_da_args_t   *args,          /* operation arguments */
949         struct xfs_dir3_icleaf_hdr *leafhdr,
950         struct xfs_buf  *bp)            /* leaf buffer */
951 {
952         int             from;           /* source leaf index */
953         xfs_dir2_leaf_t *leaf;          /* leaf structure */
954         int             loglow;         /* first leaf entry to log */
955         int             to;             /* target leaf index */
956         struct xfs_dir2_leaf_entry *ents;
957
958         leaf = bp->b_addr;
959         if (!leafhdr->stale)
960                 return;
961
962         /*
963          * Compress out the stale entries in place.
964          */
965         ents = xfs_dir3_leaf_ents_p(leaf);
966         for (from = to = 0, loglow = -1; from < leafhdr->count; from++) {
967                 if (ents[from].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
968                         continue;
969                 /*
970                  * Only actually copy the entries that are different.
971                  */
972                 if (from > to) {
973                         if (loglow == -1)
974                                 loglow = to;
975                         ents[to] = ents[from];
976                 }
977                 to++;
978         }
979         /*
980          * Update and log the header, log the leaf entries.
981          */
982         ASSERT(leafhdr->stale == from - to);
983         leafhdr->count -= leafhdr->stale;
984         leafhdr->stale = 0;
985
986         xfs_dir3_leaf_hdr_to_disk(leaf, leafhdr);
987         xfs_dir3_leaf_log_header(args->trans, bp);
988         if (loglow != -1)
989                 xfs_dir3_leaf_log_ents(args->trans, bp, loglow, to - 1);
990 }
991
992 /*
993  * Compact the leaf entries, removing stale ones.
994  * Leave one stale entry behind - the one closest to our
995  * insertion index - and the caller will shift that one to our insertion
996  * point later.
997  * Return new insertion index, where the remaining stale entry is,
998  * and leaf logging indices.
999  */
1000 void
1001 xfs_dir3_leaf_compact_x1(
1002         struct xfs_dir3_icleaf_hdr *leafhdr,
1003         struct xfs_dir2_leaf_entry *ents,
1004         int             *indexp,        /* insertion index */
1005         int             *lowstalep,     /* out: stale entry before us */
1006         int             *highstalep,    /* out: stale entry after us */
1007         int             *lowlogp,       /* out: low log index */
1008         int             *highlogp)      /* out: high log index */
1009 {
1010         int             from;           /* source copy index */
1011         int             highstale;      /* stale entry at/after index */
1012         int             index;          /* insertion index */
1013         int             keepstale;      /* source index of kept stale */
1014         int             lowstale;       /* stale entry before index */
1015         int             newindex=0;     /* new insertion index */
1016         int             to;             /* destination copy index */
1017
1018         ASSERT(leafhdr->stale > 1);
1019         index = *indexp;
1020
1021         xfs_dir3_leaf_find_stale(leafhdr, ents, index, &lowstale, &highstale);
1022
1023         /*
1024          * Pick the better of lowstale and highstale.
1025          */
1026         if (lowstale >= 0 &&
1027             (highstale == leafhdr->count ||
1028              index - lowstale <= highstale - index))
1029                 keepstale = lowstale;
1030         else
1031                 keepstale = highstale;
1032         /*
1033          * Copy the entries in place, removing all the stale entries
1034          * except keepstale.
1035          */
1036         for (from = to = 0; from < leafhdr->count; from++) {
1037                 /*
1038                  * Notice the new value of index.
1039                  */
1040                 if (index == from)
1041                         newindex = to;
1042                 if (from != keepstale &&
1043                     ents[from].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR)) {
1044                         if (from == to)
1045                                 *lowlogp = to;
1046                         continue;
1047                 }
1048                 /*
1049                  * Record the new keepstale value for the insertion.
1050                  */
1051                 if (from == keepstale)
1052                         lowstale = highstale = to;
1053                 /*
1054                  * Copy only the entries that have moved.
1055                  */
1056                 if (from > to)
1057                         ents[to] = ents[from];
1058                 to++;
1059         }
1060         ASSERT(from > to);
1061         /*
1062          * If the insertion point was past the last entry,
1063          * set the new insertion point accordingly.
1064          */
1065         if (index == from)
1066                 newindex = to;
1067         *indexp = newindex;
1068         /*
1069          * Adjust the leaf header values.
1070          */
1071         leafhdr->count -= from - to;
1072         leafhdr->stale = 1;
1073         /*
1074          * Remember the low/high stale value only in the "right"
1075          * direction.
1076          */
1077         if (lowstale >= newindex)
1078                 lowstale = -1;
1079         else
1080                 highstale = leafhdr->count;
1081         *highlogp = leafhdr->count - 1;
1082         *lowstalep = lowstale;
1083         *highstalep = highstale;
1084 }
1085
1086 /*
1087  * Log the bests entries indicated from a leaf1 block.
1088  */
1089 static void
1090 xfs_dir3_leaf_log_bests(
1091         xfs_trans_t             *tp,            /* transaction pointer */
1092         struct xfs_buf          *bp,            /* leaf buffer */
1093         int                     first,          /* first entry to log */
1094         int                     last)           /* last entry to log */
1095 {
1096         __be16                  *firstb;        /* pointer to first entry */
1097         __be16                  *lastb;         /* pointer to last entry */
1098         struct xfs_dir2_leaf    *leaf = bp->b_addr;
1099         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1100
1101         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1102                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC));
1103
1104         ltp = xfs_dir2_leaf_tail_p(tp->t_mountp, leaf);
1105         firstb = xfs_dir2_leaf_bests_p(ltp) + first;
1106         lastb = xfs_dir2_leaf_bests_p(ltp) + last;
1107         xfs_trans_log_buf(tp, bp, (uint)((char *)firstb - (char *)leaf),
1108                 (uint)((char *)lastb - (char *)leaf + sizeof(*lastb) - 1));
1109 }
1110
1111 /*
1112  * Log the leaf entries indicated from a leaf1 or leafn block.
1113  */
1114 void
1115 xfs_dir3_leaf_log_ents(
1116         xfs_trans_t             *tp,            /* transaction pointer */
1117         struct xfs_buf          *bp,            /* leaf buffer */
1118         int                     first,          /* first entry to log */
1119         int                     last)           /* last entry to log */
1120 {
1121         xfs_dir2_leaf_entry_t   *firstlep;      /* pointer to first entry */
1122         xfs_dir2_leaf_entry_t   *lastlep;       /* pointer to last entry */
1123         struct xfs_dir2_leaf    *leaf = bp->b_addr;
1124         struct xfs_dir2_leaf_entry *ents;
1125
1126         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1127                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
1128                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
1129                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC));
1130
1131         ents = xfs_dir3_leaf_ents_p(leaf);
1132         firstlep = &ents[first];
1133         lastlep = &ents[last];
1134         xfs_trans_log_buf(tp, bp, (uint)((char *)firstlep - (char *)leaf),
1135                 (uint)((char *)lastlep - (char *)leaf + sizeof(*lastlep) - 1));
1136 }
1137
1138 /*
1139  * Log the header of the leaf1 or leafn block.
1140  */
1141 void
1142 xfs_dir3_leaf_log_header(
1143         struct xfs_trans        *tp,
1144         struct xfs_buf          *bp)
1145 {
1146         struct xfs_dir2_leaf    *leaf = bp->b_addr;
1147
1148         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1149                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
1150                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
1151                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC));
1152
1153         xfs_trans_log_buf(tp, bp, (uint)((char *)&leaf->hdr - (char *)leaf),
1154                           xfs_dir3_leaf_hdr_size(leaf) - 1);
1155 }
1156
1157 /*
1158  * Log the tail of the leaf1 block.
1159  */
1160 STATIC void
1161 xfs_dir3_leaf_log_tail(
1162         struct xfs_trans        *tp,
1163         struct xfs_buf          *bp)
1164 {
1165         struct xfs_dir2_leaf    *leaf = bp->b_addr;
1166         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1167         struct xfs_mount        *mp = tp->t_mountp;
1168
1169         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAF1_MAGIC) ||
1170                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
1171                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC) ||
1172                leaf->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC));
1173
1174         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1175         xfs_trans_log_buf(tp, bp, (uint)((char *)ltp - (char *)leaf),
1176                 (uint)(mp->m_dirblksize - 1));
1177 }
1178
1179 /*
1180  * Look up the entry referred to by args in the leaf format directory.
1181  * Most of the work is done by the xfs_dir2_leaf_lookup_int routine which
1182  * is also used by the node-format code.
1183  */
1184 int
1185 xfs_dir2_leaf_lookup(
1186         xfs_da_args_t           *args)          /* operation arguments */
1187 {
1188         struct xfs_buf          *dbp;           /* data block buffer */
1189         xfs_dir2_data_entry_t   *dep;           /* data block entry */
1190         xfs_inode_t             *dp;            /* incore directory inode */
1191         int                     error;          /* error return code */
1192         int                     index;          /* found entry index */
1193         struct xfs_buf          *lbp;           /* leaf buffer */
1194         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1195         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1196         xfs_trans_t             *tp;            /* transaction pointer */
1197         struct xfs_dir2_leaf_entry *ents;
1198
1199         trace_xfs_dir2_leaf_lookup(args);
1200
1201         /*
1202          * Look up name in the leaf block, returning both buffers and index.
1203          */
1204         if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1205                 return error;
1206         }
1207         tp = args->trans;
1208         dp = args->dp;
1209         xfs_dir3_leaf_check(dp->i_mount, lbp);
1210         leaf = lbp->b_addr;
1211         ents = xfs_dir3_leaf_ents_p(leaf);
1212         /*
1213          * Get to the leaf entry and contained data entry address.
1214          */
1215         lep = &ents[index];
1216
1217         /*
1218          * Point to the data entry.
1219          */
1220         dep = (xfs_dir2_data_entry_t *)
1221               ((char *)dbp->b_addr +
1222                xfs_dir2_dataptr_to_off(dp->i_mount, be32_to_cpu(lep->address)));
1223         /*
1224          * Return the found inode number & CI name if appropriate
1225          */
1226         args->inumber = be64_to_cpu(dep->inumber);
1227         error = xfs_dir_cilookup_result(args, dep->name, dep->namelen);
1228         xfs_trans_brelse(tp, dbp);
1229         xfs_trans_brelse(tp, lbp);
1230         return XFS_ERROR(error);
1231 }
1232
1233 /*
1234  * Look up name/hash in the leaf block.
1235  * Fill in indexp with the found index, and dbpp with the data buffer.
1236  * If not found dbpp will be NULL, and ENOENT comes back.
1237  * lbpp will always be filled in with the leaf buffer unless there's an error.
1238  */
1239 static int                                      /* error */
1240 xfs_dir2_leaf_lookup_int(
1241         xfs_da_args_t           *args,          /* operation arguments */
1242         struct xfs_buf          **lbpp,         /* out: leaf buffer */
1243         int                     *indexp,        /* out: index in leaf block */
1244         struct xfs_buf          **dbpp)         /* out: data buffer */
1245 {
1246         xfs_dir2_db_t           curdb = -1;     /* current data block number */
1247         struct xfs_buf          *dbp = NULL;    /* data buffer */
1248         xfs_dir2_data_entry_t   *dep;           /* data entry */
1249         xfs_inode_t             *dp;            /* incore directory inode */
1250         int                     error;          /* error return code */
1251         int                     index;          /* index in leaf block */
1252         struct xfs_buf          *lbp;           /* leaf buffer */
1253         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1254         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1255         xfs_mount_t             *mp;            /* filesystem mount point */
1256         xfs_dir2_db_t           newdb;          /* new data block number */
1257         xfs_trans_t             *tp;            /* transaction pointer */
1258         xfs_dir2_db_t           cidb = -1;      /* case match data block no. */
1259         enum xfs_dacmp          cmp;            /* name compare result */
1260         struct xfs_dir2_leaf_entry *ents;
1261         struct xfs_dir3_icleaf_hdr leafhdr;
1262
1263         dp = args->dp;
1264         tp = args->trans;
1265         mp = dp->i_mount;
1266
1267         error = xfs_dir3_leaf_read(tp, dp, mp->m_dirleafblk, -1, &lbp);
1268         if (error)
1269                 return error;
1270
1271         *lbpp = lbp;
1272         leaf = lbp->b_addr;
1273         xfs_dir3_leaf_check(mp, lbp);
1274         ents = xfs_dir3_leaf_ents_p(leaf);
1275         xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
1276
1277         /*
1278          * Look for the first leaf entry with our hash value.
1279          */
1280         index = xfs_dir2_leaf_search_hash(args, lbp);
1281         /*
1282          * Loop over all the entries with the right hash value
1283          * looking to match the name.
1284          */
1285         for (lep = &ents[index];
1286              index < leafhdr.count && be32_to_cpu(lep->hashval) == args->hashval;
1287              lep++, index++) {
1288                 /*
1289                  * Skip over stale leaf entries.
1290                  */
1291                 if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
1292                         continue;
1293                 /*
1294                  * Get the new data block number.
1295                  */
1296                 newdb = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
1297                 /*
1298                  * If it's not the same as the old data block number,
1299                  * need to pitch the old one and read the new one.
1300                  */
1301                 if (newdb != curdb) {
1302                         if (dbp)
1303                                 xfs_trans_brelse(tp, dbp);
1304                         error = xfs_dir3_data_read(tp, dp,
1305                                                    xfs_dir2_db_to_da(mp, newdb),
1306                                                    -1, &dbp);
1307                         if (error) {
1308                                 xfs_trans_brelse(tp, lbp);
1309                                 return error;
1310                         }
1311                         curdb = newdb;
1312                 }
1313                 /*
1314                  * Point to the data entry.
1315                  */
1316                 dep = (xfs_dir2_data_entry_t *)((char *)dbp->b_addr +
1317                         xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address)));
1318                 /*
1319                  * Compare name and if it's an exact match, return the index
1320                  * and buffer. If it's the first case-insensitive match, store
1321                  * the index and buffer and continue looking for an exact match.
1322                  */
1323                 cmp = mp->m_dirnameops->compname(args, dep->name, dep->namelen);
1324                 if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) {
1325                         args->cmpresult = cmp;
1326                         *indexp = index;
1327                         /* case exact match: return the current buffer. */
1328                         if (cmp == XFS_CMP_EXACT) {
1329                                 *dbpp = dbp;
1330                                 return 0;
1331                         }
1332                         cidb = curdb;
1333                 }
1334         }
1335         ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
1336         /*
1337          * Here, we can only be doing a lookup (not a rename or remove).
1338          * If a case-insensitive match was found earlier, re-read the
1339          * appropriate data block if required and return it.
1340          */
1341         if (args->cmpresult == XFS_CMP_CASE) {
1342                 ASSERT(cidb != -1);
1343                 if (cidb != curdb) {
1344                         xfs_trans_brelse(tp, dbp);
1345                         error = xfs_dir3_data_read(tp, dp,
1346                                                    xfs_dir2_db_to_da(mp, cidb),
1347                                                    -1, &dbp);
1348                         if (error) {
1349                                 xfs_trans_brelse(tp, lbp);
1350                                 return error;
1351                         }
1352                 }
1353                 *dbpp = dbp;
1354                 return 0;
1355         }
1356         /*
1357          * No match found, return ENOENT.
1358          */
1359         ASSERT(cidb == -1);
1360         if (dbp)
1361                 xfs_trans_brelse(tp, dbp);
1362         xfs_trans_brelse(tp, lbp);
1363         return XFS_ERROR(ENOENT);
1364 }
1365
1366 /*
1367  * Remove an entry from a leaf format directory.
1368  */
1369 int                                             /* error */
1370 xfs_dir2_leaf_removename(
1371         xfs_da_args_t           *args)          /* operation arguments */
1372 {
1373         __be16                  *bestsp;        /* leaf block best freespace */
1374         xfs_dir2_data_hdr_t     *hdr;           /* data block header */
1375         xfs_dir2_db_t           db;             /* data block number */
1376         struct xfs_buf          *dbp;           /* data block buffer */
1377         xfs_dir2_data_entry_t   *dep;           /* data entry structure */
1378         xfs_inode_t             *dp;            /* incore directory inode */
1379         int                     error;          /* error return code */
1380         xfs_dir2_db_t           i;              /* temporary data block # */
1381         int                     index;          /* index into leaf entries */
1382         struct xfs_buf          *lbp;           /* leaf buffer */
1383         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1384         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1385         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1386         xfs_mount_t             *mp;            /* filesystem mount point */
1387         int                     needlog;        /* need to log data header */
1388         int                     needscan;       /* need to rescan data frees */
1389         xfs_dir2_data_off_t     oldbest;        /* old value of best free */
1390         xfs_trans_t             *tp;            /* transaction pointer */
1391         struct xfs_dir2_data_free *bf;          /* bestfree table */
1392         struct xfs_dir2_leaf_entry *ents;
1393         struct xfs_dir3_icleaf_hdr leafhdr;
1394
1395         trace_xfs_dir2_leaf_removename(args);
1396
1397         /*
1398          * Lookup the leaf entry, get the leaf and data blocks read in.
1399          */
1400         if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1401                 return error;
1402         }
1403         dp = args->dp;
1404         tp = args->trans;
1405         mp = dp->i_mount;
1406         leaf = lbp->b_addr;
1407         hdr = dbp->b_addr;
1408         xfs_dir3_data_check(dp, dbp);
1409         bf = xfs_dir3_data_bestfree_p(hdr);
1410         xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
1411         ents = xfs_dir3_leaf_ents_p(leaf);
1412         /*
1413          * Point to the leaf entry, use that to point to the data entry.
1414          */
1415         lep = &ents[index];
1416         db = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
1417         dep = (xfs_dir2_data_entry_t *)
1418               ((char *)hdr + xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address)));
1419         needscan = needlog = 0;
1420         oldbest = be16_to_cpu(bf[0].length);
1421         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1422         bestsp = xfs_dir2_leaf_bests_p(ltp);
1423         ASSERT(be16_to_cpu(bestsp[db]) == oldbest);
1424         /*
1425          * Mark the former data entry unused.
1426          */
1427         xfs_dir2_data_make_free(tp, dbp,
1428                 (xfs_dir2_data_aoff_t)((char *)dep - (char *)hdr),
1429                 xfs_dir2_data_entsize(dep->namelen), &needlog, &needscan);
1430         /*
1431          * We just mark the leaf entry stale by putting a null in it.
1432          */
1433         leafhdr.stale++;
1434         xfs_dir3_leaf_hdr_to_disk(leaf, &leafhdr);
1435         xfs_dir3_leaf_log_header(tp, lbp);
1436
1437         lep->address = cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
1438         xfs_dir3_leaf_log_ents(tp, lbp, index, index);
1439
1440         /*
1441          * Scan the freespace in the data block again if necessary,
1442          * log the data block header if necessary.
1443          */
1444         if (needscan)
1445                 xfs_dir2_data_freescan(mp, hdr, &needlog);
1446         if (needlog)
1447                 xfs_dir2_data_log_header(tp, dbp);
1448         /*
1449          * If the longest freespace in the data block has changed,
1450          * put the new value in the bests table and log that.
1451          */
1452         if (be16_to_cpu(bf[0].length) != oldbest) {
1453                 bestsp[db] = bf[0].length;
1454                 xfs_dir3_leaf_log_bests(tp, lbp, db, db);
1455         }
1456         xfs_dir3_data_check(dp, dbp);
1457         /*
1458          * If the data block is now empty then get rid of the data block.
1459          */
1460         if (be16_to_cpu(bf[0].length) ==
1461                         mp->m_dirblksize - xfs_dir3_data_entry_offset(hdr)) {
1462                 ASSERT(db != mp->m_dirdatablk);
1463                 if ((error = xfs_dir2_shrink_inode(args, db, dbp))) {
1464                         /*
1465                          * Nope, can't get rid of it because it caused
1466                          * allocation of a bmap btree block to do so.
1467                          * Just go on, returning success, leaving the
1468                          * empty block in place.
1469                          */
1470                         if (error == ENOSPC && args->total == 0)
1471                                 error = 0;
1472                         xfs_dir3_leaf_check(mp, lbp);
1473                         return error;
1474                 }
1475                 dbp = NULL;
1476                 /*
1477                  * If this is the last data block then compact the
1478                  * bests table by getting rid of entries.
1479                  */
1480                 if (db == be32_to_cpu(ltp->bestcount) - 1) {
1481                         /*
1482                          * Look for the last active entry (i).
1483                          */
1484                         for (i = db - 1; i > 0; i--) {
1485                                 if (bestsp[i] != cpu_to_be16(NULLDATAOFF))
1486                                         break;
1487                         }
1488                         /*
1489                          * Copy the table down so inactive entries at the
1490                          * end are removed.
1491                          */
1492                         memmove(&bestsp[db - i], bestsp,
1493                                 (be32_to_cpu(ltp->bestcount) - (db - i)) * sizeof(*bestsp));
1494                         be32_add_cpu(&ltp->bestcount, -(db - i));
1495                         xfs_dir3_leaf_log_tail(tp, lbp);
1496                         xfs_dir3_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1497                 } else
1498                         bestsp[db] = cpu_to_be16(NULLDATAOFF);
1499         }
1500         /*
1501          * If the data block was not the first one, drop it.
1502          */
1503         else if (db != mp->m_dirdatablk)
1504                 dbp = NULL;
1505
1506         xfs_dir3_leaf_check(mp, lbp);
1507         /*
1508          * See if we can convert to block form.
1509          */
1510         return xfs_dir2_leaf_to_block(args, lbp, dbp);
1511 }
1512
1513 /*
1514  * Replace the inode number in a leaf format directory entry.
1515  */
1516 int                                             /* error */
1517 xfs_dir2_leaf_replace(
1518         xfs_da_args_t           *args)          /* operation arguments */
1519 {
1520         struct xfs_buf          *dbp;           /* data block buffer */
1521         xfs_dir2_data_entry_t   *dep;           /* data block entry */
1522         xfs_inode_t             *dp;            /* incore directory inode */
1523         int                     error;          /* error return code */
1524         int                     index;          /* index of leaf entry */
1525         struct xfs_buf          *lbp;           /* leaf buffer */
1526         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1527         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1528         xfs_trans_t             *tp;            /* transaction pointer */
1529         struct xfs_dir2_leaf_entry *ents;
1530
1531         trace_xfs_dir2_leaf_replace(args);
1532
1533         /*
1534          * Look up the entry.
1535          */
1536         if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1537                 return error;
1538         }
1539         dp = args->dp;
1540         leaf = lbp->b_addr;
1541         ents = xfs_dir3_leaf_ents_p(leaf);
1542         /*
1543          * Point to the leaf entry, get data address from it.
1544          */
1545         lep = &ents[index];
1546         /*
1547          * Point to the data entry.
1548          */
1549         dep = (xfs_dir2_data_entry_t *)
1550               ((char *)dbp->b_addr +
1551                xfs_dir2_dataptr_to_off(dp->i_mount, be32_to_cpu(lep->address)));
1552         ASSERT(args->inumber != be64_to_cpu(dep->inumber));
1553         /*
1554          * Put the new inode number in, log it.
1555          */
1556         dep->inumber = cpu_to_be64(args->inumber);
1557         tp = args->trans;
1558         xfs_dir2_data_log_entry(tp, dbp, dep);
1559         xfs_dir3_leaf_check(dp->i_mount, lbp);
1560         xfs_trans_brelse(tp, lbp);
1561         return 0;
1562 }
1563
1564 /*
1565  * Return index in the leaf block (lbp) which is either the first
1566  * one with this hash value, or if there are none, the insert point
1567  * for that hash value.
1568  */
1569 int                                             /* index value */
1570 xfs_dir2_leaf_search_hash(
1571         xfs_da_args_t           *args,          /* operation arguments */
1572         struct xfs_buf          *lbp)           /* leaf buffer */
1573 {
1574         xfs_dahash_t            hash=0;         /* hash from this entry */
1575         xfs_dahash_t            hashwant;       /* hash value looking for */
1576         int                     high;           /* high leaf index */
1577         int                     low;            /* low leaf index */
1578         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1579         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1580         int                     mid=0;          /* current leaf index */
1581         struct xfs_dir2_leaf_entry *ents;
1582         struct xfs_dir3_icleaf_hdr leafhdr;
1583
1584         leaf = lbp->b_addr;
1585         ents = xfs_dir3_leaf_ents_p(leaf);
1586         xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
1587
1588 #ifndef __KERNEL__
1589         if (!leafhdr.count)
1590                 return 0;
1591 #endif
1592         /*
1593          * Note, the table cannot be empty, so we have to go through the loop.
1594          * Binary search the leaf entries looking for our hash value.
1595          */
1596         for (lep = ents, low = 0, high = leafhdr.count - 1,
1597                 hashwant = args->hashval;
1598              low <= high; ) {
1599                 mid = (low + high) >> 1;
1600                 if ((hash = be32_to_cpu(lep[mid].hashval)) == hashwant)
1601                         break;
1602                 if (hash < hashwant)
1603                         low = mid + 1;
1604                 else
1605                         high = mid - 1;
1606         }
1607         /*
1608          * Found one, back up through all the equal hash values.
1609          */
1610         if (hash == hashwant) {
1611                 while (mid > 0 && be32_to_cpu(lep[mid - 1].hashval) == hashwant) {
1612                         mid--;
1613                 }
1614         }
1615         /*
1616          * Need to point to an entry higher than ours.
1617          */
1618         else if (hash < hashwant)
1619                 mid++;
1620         return mid;
1621 }
1622
1623 /*
1624  * Trim off a trailing data block.  We know it's empty since the leaf
1625  * freespace table says so.
1626  */
1627 int                                             /* error */
1628 xfs_dir2_leaf_trim_data(
1629         xfs_da_args_t           *args,          /* operation arguments */
1630         struct xfs_buf          *lbp,           /* leaf buffer */
1631         xfs_dir2_db_t           db)             /* data block number */
1632 {
1633         __be16                  *bestsp;        /* leaf bests table */
1634         struct xfs_buf          *dbp;           /* data block buffer */
1635         xfs_inode_t             *dp;            /* incore directory inode */
1636         int                     error;          /* error return value */
1637         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1638         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1639         xfs_mount_t             *mp;            /* filesystem mount point */
1640         xfs_trans_t             *tp;            /* transaction pointer */
1641
1642         dp = args->dp;
1643         mp = dp->i_mount;
1644         tp = args->trans;
1645         /*
1646          * Read the offending data block.  We need its buffer.
1647          */
1648         error = xfs_dir3_data_read(tp, dp, xfs_dir2_db_to_da(mp, db), -1, &dbp);
1649         if (error)
1650                 return error;
1651
1652         leaf = lbp->b_addr;
1653         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1654
1655 #ifdef DEBUG
1656 {
1657         struct xfs_dir2_data_hdr *hdr = dbp->b_addr;
1658         struct xfs_dir2_data_free *bf = xfs_dir3_data_bestfree_p(hdr);
1659
1660         ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC) ||
1661                hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC));
1662         ASSERT(be16_to_cpu(bf[0].length) ==
1663                mp->m_dirblksize - xfs_dir3_data_entry_offset(hdr));
1664         ASSERT(db == be32_to_cpu(ltp->bestcount) - 1);
1665 }
1666 #endif
1667
1668         /*
1669          * Get rid of the data block.
1670          */
1671         if ((error = xfs_dir2_shrink_inode(args, db, dbp))) {
1672                 ASSERT(error != ENOSPC);
1673                 xfs_trans_brelse(tp, dbp);
1674                 return error;
1675         }
1676         /*
1677          * Eliminate the last bests entry from the table.
1678          */
1679         bestsp = xfs_dir2_leaf_bests_p(ltp);
1680         be32_add_cpu(&ltp->bestcount, -1);
1681         memmove(&bestsp[1], &bestsp[0], be32_to_cpu(ltp->bestcount) * sizeof(*bestsp));
1682         xfs_dir3_leaf_log_tail(tp, lbp);
1683         xfs_dir3_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1684         return 0;
1685 }
1686
1687 static inline size_t
1688 xfs_dir3_leaf_size(
1689         struct xfs_dir3_icleaf_hdr      *hdr,
1690         int                             counts)
1691 {
1692         int     entries;
1693         int     hdrsize;
1694
1695         entries = hdr->count - hdr->stale;
1696         if (hdr->magic == XFS_DIR2_LEAF1_MAGIC ||
1697             hdr->magic == XFS_DIR2_LEAFN_MAGIC)
1698                 hdrsize = sizeof(struct xfs_dir2_leaf_hdr);
1699         else
1700                 hdrsize = sizeof(struct xfs_dir3_leaf_hdr);
1701
1702         return hdrsize + entries * sizeof(xfs_dir2_leaf_entry_t)
1703                        + counts * sizeof(xfs_dir2_data_off_t)
1704                        + sizeof(xfs_dir2_leaf_tail_t);
1705 }
1706
1707 /*
1708  * Convert node form directory to leaf form directory.
1709  * The root of the node form dir needs to already be a LEAFN block.
1710  * Just return if we can't do anything.
1711  */
1712 int                                             /* error */
1713 xfs_dir2_node_to_leaf(
1714         xfs_da_state_t          *state)         /* directory operation state */
1715 {
1716         xfs_da_args_t           *args;          /* operation arguments */
1717         xfs_inode_t             *dp;            /* incore directory inode */
1718         int                     error;          /* error return code */
1719         struct xfs_buf          *fbp;           /* buffer for freespace block */
1720         xfs_fileoff_t           fo;             /* freespace file offset */
1721         xfs_dir2_free_t         *free;          /* freespace structure */
1722         struct xfs_buf          *lbp;           /* buffer for leaf block */
1723         xfs_dir2_leaf_tail_t    *ltp;           /* tail of leaf structure */
1724         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1725         xfs_mount_t             *mp;            /* filesystem mount point */
1726         int                     rval;           /* successful free trim? */
1727         xfs_trans_t             *tp;            /* transaction pointer */
1728         struct xfs_dir3_icleaf_hdr leafhdr;
1729         struct xfs_dir3_icfree_hdr freehdr;
1730
1731         /*
1732          * There's more than a leaf level in the btree, so there must
1733          * be multiple leafn blocks.  Give up.
1734          */
1735         if (state->path.active > 1)
1736                 return 0;
1737         args = state->args;
1738
1739         trace_xfs_dir2_node_to_leaf(args);
1740
1741         mp = state->mp;
1742         dp = args->dp;
1743         tp = args->trans;
1744         /*
1745          * Get the last offset in the file.
1746          */
1747         if ((error = xfs_bmap_last_offset(tp, dp, &fo, XFS_DATA_FORK))) {
1748                 return error;
1749         }
1750         fo -= mp->m_dirblkfsbs;
1751         /*
1752          * If there are freespace blocks other than the first one,
1753          * take this opportunity to remove trailing empty freespace blocks
1754          * that may have been left behind during no-space-reservation
1755          * operations.
1756          */
1757         while (fo > mp->m_dirfreeblk) {
1758                 if ((error = xfs_dir2_node_trim_free(args, fo, &rval))) {
1759                         return error;
1760                 }
1761                 if (rval)
1762                         fo -= mp->m_dirblkfsbs;
1763                 else
1764                         return 0;
1765         }
1766         /*
1767          * Now find the block just before the freespace block.
1768          */
1769         if ((error = xfs_bmap_last_before(tp, dp, &fo, XFS_DATA_FORK))) {
1770                 return error;
1771         }
1772         /*
1773          * If it's not the single leaf block, give up.
1774          */
1775         if (XFS_FSB_TO_B(mp, fo) > XFS_DIR2_LEAF_OFFSET + mp->m_dirblksize)
1776                 return 0;
1777         lbp = state->path.blk[0].bp;
1778         leaf = lbp->b_addr;
1779         xfs_dir3_leaf_hdr_from_disk(&leafhdr, leaf);
1780
1781         ASSERT(leafhdr.magic == XFS_DIR2_LEAFN_MAGIC ||
1782                leafhdr.magic == XFS_DIR3_LEAFN_MAGIC);
1783
1784         /*
1785          * Read the freespace block.
1786          */
1787         error = xfs_dir2_free_read(tp, dp,  mp->m_dirfreeblk, &fbp);
1788         if (error)
1789                 return error;
1790         free = fbp->b_addr;
1791         xfs_dir3_free_hdr_from_disk(&freehdr, free);
1792
1793         ASSERT(!freehdr.firstdb);
1794
1795         /*
1796          * Now see if the leafn and free data will fit in a leaf1.
1797          * If not, release the buffer and give up.
1798          */
1799         if (xfs_dir3_leaf_size(&leafhdr, freehdr.nvalid) > mp->m_dirblksize) {
1800                 xfs_trans_brelse(tp, fbp);
1801                 return 0;
1802         }
1803
1804         /*
1805          * If the leaf has any stale entries in it, compress them out.
1806          */
1807         if (leafhdr.stale)
1808                 xfs_dir3_leaf_compact(args, &leafhdr, lbp);
1809
1810         lbp->b_ops = &xfs_dir3_leaf1_buf_ops;
1811         xfs_trans_buf_set_type(tp, lbp, XFS_BLFT_DIR_LEAF1_BUF);
1812         leafhdr.magic = (leafhdr.magic == XFS_DIR2_LEAFN_MAGIC)
1813                                         ? XFS_DIR2_LEAF1_MAGIC
1814                                         : XFS_DIR3_LEAF1_MAGIC;
1815
1816         /*
1817          * Set up the leaf tail from the freespace block.
1818          */
1819         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
1820         ltp->bestcount = cpu_to_be32(freehdr.nvalid);
1821
1822         /*
1823          * Set up the leaf bests table.
1824          */
1825         memcpy(xfs_dir2_leaf_bests_p(ltp), xfs_dir3_free_bests_p(mp, free),
1826                 freehdr.nvalid * sizeof(xfs_dir2_data_off_t));
1827
1828         xfs_dir3_leaf_hdr_to_disk(leaf, &leafhdr);
1829         xfs_dir3_leaf_log_header(tp, lbp);
1830         xfs_dir3_leaf_log_bests(tp, lbp, 0, be32_to_cpu(ltp->bestcount) - 1);
1831         xfs_dir3_leaf_log_tail(tp, lbp);
1832         xfs_dir3_leaf_check(mp, lbp);
1833
1834         /*
1835          * Get rid of the freespace block.
1836          */
1837         error = xfs_dir2_shrink_inode(args, XFS_DIR2_FREE_FIRSTDB(mp), fbp);
1838         if (error) {
1839                 /*
1840                  * This can't fail here because it can only happen when
1841                  * punching out the middle of an extent, and this is an
1842                  * isolated block.
1843                  */
1844                 ASSERT(error != ENOSPC);
1845                 return error;
1846         }
1847         fbp = NULL;
1848         /*
1849          * Now see if we can convert the single-leaf directory
1850          * down to a block form directory.
1851          * This routine always kills the dabuf for the leaf, so
1852          * eliminate it from the path.
1853          */
1854         error = xfs_dir2_leaf_to_block(args, lbp, NULL);
1855         state->path.blk[0].bp = NULL;
1856         return error;
1857 }