Merge master.kernel.org:/home/rmk/linux-2.6-mmc
[linux-2.6] / fs / xfs / xfs_dir2_leaf.c
1 /*
2  * Copyright (c) 2000-2003 Silicon Graphics, Inc.  All Rights Reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms of version 2 of the GNU General Public License as
6  * published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it would be useful, but
9  * WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
11  *
12  * Further, this software is distributed without any warranty that it is
13  * free of the rightful claim of any third person regarding infringement
14  * or the like.  Any license provided herein, whether implied or
15  * otherwise, applies only to this software file.  Patent licenses, if
16  * any, provided herein do not apply to combinations of this program with
17  * other software, or any other product whatsoever.
18  *
19  * You should have received a copy of the GNU General Public License along
20  * with this program; if not, write the Free Software Foundation, Inc., 59
21  * Temple Place - Suite 330, Boston MA 02111-1307, USA.
22  *
23  * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
24  * Mountain View, CA  94043, or:
25  *
26  * http://www.sgi.com
27  *
28  * For further information regarding this notice, see:
29  *
30  * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
31  */
32
33 /*
34  * xfs_dir2_leaf.c
35  * XFS directory version 2 implementation - single leaf form
36  * see xfs_dir2_leaf.h for data structures.
37  * These directories have multiple XFS_DIR2_DATA blocks and one
38  * XFS_DIR2_LEAF1 block containing the hash table and freespace map.
39  */
40
41 #include "xfs.h"
42
43 #include "xfs_macros.h"
44 #include "xfs_types.h"
45 #include "xfs_inum.h"
46 #include "xfs_log.h"
47 #include "xfs_trans.h"
48 #include "xfs_sb.h"
49 #include "xfs_ag.h"
50 #include "xfs_dir.h"
51 #include "xfs_dir2.h"
52 #include "xfs_dmapi.h"
53 #include "xfs_mount.h"
54 #include "xfs_bmap_btree.h"
55 #include "xfs_attr_sf.h"
56 #include "xfs_dir_sf.h"
57 #include "xfs_dir2_sf.h"
58 #include "xfs_dinode.h"
59 #include "xfs_inode.h"
60 #include "xfs_bmap.h"
61 #include "xfs_da_btree.h"
62 #include "xfs_dir2_data.h"
63 #include "xfs_dir2_leaf.h"
64 #include "xfs_dir2_block.h"
65 #include "xfs_dir2_node.h"
66 #include "xfs_dir2_trace.h"
67 #include "xfs_error.h"
68 #include "xfs_bit.h"
69
70 /*
71  * Local function declarations.
72  */
73 #ifdef DEBUG
74 static void xfs_dir2_leaf_check(xfs_inode_t *dp, xfs_dabuf_t *bp);
75 #else
76 #define xfs_dir2_leaf_check(dp, bp)
77 #endif
78 static int xfs_dir2_leaf_lookup_int(xfs_da_args_t *args, xfs_dabuf_t **lbpp,
79                                     int *indexp, xfs_dabuf_t **dbpp);
80 static void xfs_dir2_leaf_log_bests(struct xfs_trans *tp, struct xfs_dabuf *bp,
81                                     int first, int last);
82 static void xfs_dir2_leaf_log_tail(struct xfs_trans *tp, struct xfs_dabuf *bp);
83
84
85 /*
86  * Convert a block form directory to a leaf form directory.
87  */
88 int                                             /* error */
89 xfs_dir2_block_to_leaf(
90         xfs_da_args_t           *args,          /* operation arguments */
91         xfs_dabuf_t             *dbp)           /* input block's buffer */
92 {
93         xfs_dir2_data_off_t     *bestsp;        /* leaf's bestsp entries */
94         xfs_dablk_t             blkno;          /* leaf block's bno */
95         xfs_dir2_block_t        *block;         /* block structure */
96         xfs_dir2_leaf_entry_t   *blp;           /* block's leaf entries */
97         xfs_dir2_block_tail_t   *btp;           /* block's tail */
98         xfs_inode_t             *dp;            /* incore directory inode */
99         int                     error;          /* error return code */
100         xfs_dabuf_t             *lbp;           /* leaf block's buffer */
101         xfs_dir2_db_t           ldb;            /* leaf block's bno */
102         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
103         xfs_dir2_leaf_tail_t    *ltp;           /* leaf's tail */
104         xfs_mount_t             *mp;            /* filesystem mount point */
105         int                     needlog;        /* need to log block header */
106         int                     needscan;       /* need to rescan bestfree */
107         xfs_trans_t             *tp;            /* transaction pointer */
108
109         xfs_dir2_trace_args_b("block_to_leaf", args, dbp);
110         dp = args->dp;
111         mp = dp->i_mount;
112         tp = args->trans;
113         /*
114          * Add the leaf block to the inode.
115          * This interface will only put blocks in the leaf/node range.
116          * Since that's empty now, we'll get the root (block 0 in range).
117          */
118         if ((error = xfs_da_grow_inode(args, &blkno))) {
119                 return error;
120         }
121         ldb = XFS_DIR2_DA_TO_DB(mp, blkno);
122         ASSERT(ldb == XFS_DIR2_LEAF_FIRSTDB(mp));
123         /*
124          * Initialize the leaf block, get a buffer for it.
125          */
126         if ((error = xfs_dir2_leaf_init(args, ldb, &lbp, XFS_DIR2_LEAF1_MAGIC))) {
127                 return error;
128         }
129         ASSERT(lbp != NULL);
130         leaf = lbp->data;
131         block = dbp->data;
132         xfs_dir2_data_check(dp, dbp);
133         btp = XFS_DIR2_BLOCK_TAIL_P(mp, block);
134         blp = XFS_DIR2_BLOCK_LEAF_P(btp);
135         /*
136          * Set the counts in the leaf header.
137          */
138         INT_COPY(leaf->hdr.count, btp->count, ARCH_CONVERT); /* INT_: type change */
139         INT_COPY(leaf->hdr.stale, btp->stale, ARCH_CONVERT); /* INT_: type change */
140         /*
141          * Could compact these but I think we always do the conversion
142          * after squeezing out stale entries.
143          */
144         memcpy(leaf->ents, blp, INT_GET(btp->count, ARCH_CONVERT) * sizeof(xfs_dir2_leaf_entry_t));
145         xfs_dir2_leaf_log_ents(tp, lbp, 0, INT_GET(leaf->hdr.count, ARCH_CONVERT) - 1);
146         needscan = 0;
147         needlog = 1;
148         /*
149          * Make the space formerly occupied by the leaf entries and block
150          * tail be free.
151          */
152         xfs_dir2_data_make_free(tp, dbp,
153                 (xfs_dir2_data_aoff_t)((char *)blp - (char *)block),
154                 (xfs_dir2_data_aoff_t)((char *)block + mp->m_dirblksize -
155                                        (char *)blp),
156                 &needlog, &needscan);
157         /*
158          * Fix up the block header, make it a data block.
159          */
160         INT_SET(block->hdr.magic, ARCH_CONVERT, XFS_DIR2_DATA_MAGIC);
161         if (needscan)
162                 xfs_dir2_data_freescan(mp, (xfs_dir2_data_t *)block, &needlog,
163                         NULL);
164         /*
165          * Set up leaf tail and bests table.
166          */
167         ltp = XFS_DIR2_LEAF_TAIL_P(mp, leaf);
168         INT_SET(ltp->bestcount, ARCH_CONVERT, 1);
169         bestsp = XFS_DIR2_LEAF_BESTS_P(ltp);
170         INT_COPY(bestsp[0], block->hdr.bestfree[0].length, ARCH_CONVERT);
171         /*
172          * Log the data header and leaf bests table.
173          */
174         if (needlog)
175                 xfs_dir2_data_log_header(tp, dbp);
176         xfs_dir2_leaf_check(dp, lbp);
177         xfs_dir2_data_check(dp, dbp);
178         xfs_dir2_leaf_log_bests(tp, lbp, 0, 0);
179         xfs_da_buf_done(lbp);
180         return 0;
181 }
182
183 /*
184  * Add an entry to a leaf form directory.
185  */
186 int                                             /* error */
187 xfs_dir2_leaf_addname(
188         xfs_da_args_t           *args)          /* operation arguments */
189 {
190         xfs_dir2_data_off_t     *bestsp;        /* freespace table in leaf */
191         int                     compact;        /* need to compact leaves */
192         xfs_dir2_data_t         *data;          /* data block structure */
193         xfs_dabuf_t             *dbp;           /* data block buffer */
194         xfs_dir2_data_entry_t   *dep;           /* data block entry */
195         xfs_inode_t             *dp;            /* incore directory inode */
196         xfs_dir2_data_unused_t  *dup;           /* data unused entry */
197         int                     error;          /* error return value */
198         int                     grown;          /* allocated new data block */
199         int                     highstale;      /* index of next stale leaf */
200         int                     i;              /* temporary, index */
201         int                     index;          /* leaf table position */
202         xfs_dabuf_t             *lbp;           /* leaf's buffer */
203         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
204         int                     length;         /* length of new entry */
205         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry table pointer */
206         int                     lfloglow;       /* low leaf logging index */
207         int                     lfloghigh;      /* high leaf logging index */
208         int                     lowstale;       /* index of prev stale leaf */
209         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail pointer */
210         xfs_mount_t             *mp;            /* filesystem mount point */
211         int                     needbytes;      /* leaf block bytes needed */
212         int                     needlog;        /* need to log data header */
213         int                     needscan;       /* need to rescan data free */
214         xfs_dir2_data_off_t     *tagp;          /* end of data entry */
215         xfs_trans_t             *tp;            /* transaction pointer */
216         xfs_dir2_db_t           use_block;      /* data block number */
217
218         xfs_dir2_trace_args("leaf_addname", args);
219         dp = args->dp;
220         tp = args->trans;
221         mp = dp->i_mount;
222         /*
223          * Read the leaf block.
224          */
225         error = xfs_da_read_buf(tp, dp, mp->m_dirleafblk, -1, &lbp,
226                 XFS_DATA_FORK);
227         if (error) {
228                 return error;
229         }
230         ASSERT(lbp != NULL);
231         /*
232          * Look up the entry by hash value and name.
233          * We know it's not there, our caller has already done a lookup.
234          * So the index is of the entry to insert in front of.
235          * But if there are dup hash values the index is of the first of those.
236          */
237         index = xfs_dir2_leaf_search_hash(args, lbp);
238         leaf = lbp->data;
239         ltp = XFS_DIR2_LEAF_TAIL_P(mp, leaf);
240         bestsp = XFS_DIR2_LEAF_BESTS_P(ltp);
241         length = XFS_DIR2_DATA_ENTSIZE(args->namelen);
242         /*
243          * See if there are any entries with the same hash value
244          * and space in their block for the new entry.
245          * This is good because it puts multiple same-hash value entries
246          * in a data block, improving the lookup of those entries.
247          */
248         for (use_block = -1, lep = &leaf->ents[index];
249              index < INT_GET(leaf->hdr.count, ARCH_CONVERT) && INT_GET(lep->hashval, ARCH_CONVERT) == args->hashval;
250              index++, lep++) {
251                 if (INT_GET(lep->address, ARCH_CONVERT) == XFS_DIR2_NULL_DATAPTR)
252                         continue;
253                 i = XFS_DIR2_DATAPTR_TO_DB(mp, INT_GET(lep->address, ARCH_CONVERT));
254                 ASSERT(i < INT_GET(ltp->bestcount, ARCH_CONVERT));
255                 ASSERT(INT_GET(bestsp[i], ARCH_CONVERT) != NULLDATAOFF);
256                 if (INT_GET(bestsp[i], ARCH_CONVERT) >= length) {
257                         use_block = i;
258                         break;
259                 }
260         }
261         /*
262          * Didn't find a block yet, linear search all the data blocks.
263          */
264         if (use_block == -1) {
265                 for (i = 0; i < INT_GET(ltp->bestcount, ARCH_CONVERT); i++) {
266                         /*
267                          * Remember a block we see that's missing.
268                          */
269                         if (INT_GET(bestsp[i], ARCH_CONVERT) == NULLDATAOFF && use_block == -1)
270                                 use_block = i;
271                         else if (INT_GET(bestsp[i], ARCH_CONVERT) >= length) {
272                                 use_block = i;
273                                 break;
274                         }
275                 }
276         }
277         /*
278          * How many bytes do we need in the leaf block?
279          */
280         needbytes =
281                 (leaf->hdr.stale ? 0 : (uint)sizeof(leaf->ents[0])) +
282                 (use_block != -1 ? 0 : (uint)sizeof(leaf->bests[0]));
283         /*
284          * Now kill use_block if it refers to a missing block, so we
285          * can use it as an indication of allocation needed.
286          */
287         if (use_block != -1 && INT_GET(bestsp[use_block], ARCH_CONVERT) == NULLDATAOFF)
288                 use_block = -1;
289         /*
290          * If we don't have enough free bytes but we can make enough
291          * by compacting out stale entries, we'll do that.
292          */
293         if ((char *)bestsp - (char *)&leaf->ents[INT_GET(leaf->hdr.count, ARCH_CONVERT)] < needbytes &&
294             INT_GET(leaf->hdr.stale, ARCH_CONVERT) > 1) {
295                 compact = 1;
296         }
297         /*
298          * Otherwise if we don't have enough free bytes we need to
299          * convert to node form.
300          */
301         else if ((char *)bestsp - (char *)&leaf->ents[INT_GET(leaf->hdr.count, ARCH_CONVERT)] <
302                  needbytes) {
303                 /*
304                  * Just checking or no space reservation, give up.
305                  */
306                 if (args->justcheck || args->total == 0) {
307                         xfs_da_brelse(tp, lbp);
308                         return XFS_ERROR(ENOSPC);
309                 }
310                 /*
311                  * Convert to node form.
312                  */
313                 error = xfs_dir2_leaf_to_node(args, lbp);
314                 xfs_da_buf_done(lbp);
315                 if (error)
316                         return error;
317                 /*
318                  * Then add the new entry.
319                  */
320                 return xfs_dir2_node_addname(args);
321         }
322         /*
323          * Otherwise it will fit without compaction.
324          */
325         else
326                 compact = 0;
327         /*
328          * If just checking, then it will fit unless we needed to allocate
329          * a new data block.
330          */
331         if (args->justcheck) {
332                 xfs_da_brelse(tp, lbp);
333                 return use_block == -1 ? XFS_ERROR(ENOSPC) : 0;
334         }
335         /*
336          * If no allocations are allowed, return now before we've
337          * changed anything.
338          */
339         if (args->total == 0 && use_block == -1) {
340                 xfs_da_brelse(tp, lbp);
341                 return XFS_ERROR(ENOSPC);
342         }
343         /*
344          * Need to compact the leaf entries, removing stale ones.
345          * Leave one stale entry behind - the one closest to our
346          * insertion index - and we'll shift that one to our insertion
347          * point later.
348          */
349         if (compact) {
350                 xfs_dir2_leaf_compact_x1(lbp, &index, &lowstale, &highstale,
351                         &lfloglow, &lfloghigh);
352         }
353         /*
354          * There are stale entries, so we'll need log-low and log-high
355          * impossibly bad values later.
356          */
357         else if (INT_GET(leaf->hdr.stale, ARCH_CONVERT)) {
358                 lfloglow = INT_GET(leaf->hdr.count, ARCH_CONVERT);
359                 lfloghigh = -1;
360         }
361         /*
362          * If there was no data block space found, we need to allocate
363          * a new one.
364          */
365         if (use_block == -1) {
366                 /*
367                  * Add the new data block.
368                  */
369                 if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_DATA_SPACE,
370                                 &use_block))) {
371                         xfs_da_brelse(tp, lbp);
372                         return error;
373                 }
374                 /*
375                  * Initialize the block.
376                  */
377                 if ((error = xfs_dir2_data_init(args, use_block, &dbp))) {
378                         xfs_da_brelse(tp, lbp);
379                         return error;
380                 }
381                 /*
382                  * If we're adding a new data block on the end we need to
383                  * extend the bests table.  Copy it up one entry.
384                  */
385                 if (use_block >= INT_GET(ltp->bestcount, ARCH_CONVERT)) {
386                         bestsp--;
387                         memmove(&bestsp[0], &bestsp[1],
388                                 INT_GET(ltp->bestcount, ARCH_CONVERT) * sizeof(bestsp[0]));
389                         INT_MOD(ltp->bestcount, ARCH_CONVERT, +1);
390                         xfs_dir2_leaf_log_tail(tp, lbp);
391                         xfs_dir2_leaf_log_bests(tp, lbp, 0, INT_GET(ltp->bestcount, ARCH_CONVERT) - 1);
392                 }
393                 /*
394                  * If we're filling in a previously empty block just log it.
395                  */
396                 else
397                         xfs_dir2_leaf_log_bests(tp, lbp, use_block, use_block);
398                 data = dbp->data;
399                 INT_COPY(bestsp[use_block], data->hdr.bestfree[0].length, ARCH_CONVERT);
400                 grown = 1;
401         }
402         /*
403          * Already had space in some data block.
404          * Just read that one in.
405          */
406         else {
407                 if ((error =
408                     xfs_da_read_buf(tp, dp, XFS_DIR2_DB_TO_DA(mp, use_block),
409                             -1, &dbp, XFS_DATA_FORK))) {
410                         xfs_da_brelse(tp, lbp);
411                         return error;
412                 }
413                 data = dbp->data;
414                 grown = 0;
415         }
416         xfs_dir2_data_check(dp, dbp);
417         /*
418          * Point to the biggest freespace in our data block.
419          */
420         dup = (xfs_dir2_data_unused_t *)
421               ((char *)data + INT_GET(data->hdr.bestfree[0].offset, ARCH_CONVERT));
422         ASSERT(INT_GET(dup->length, ARCH_CONVERT) >= length);
423         needscan = needlog = 0;
424         /*
425          * Mark the initial part of our freespace in use for the new entry.
426          */
427         xfs_dir2_data_use_free(tp, dbp, dup,
428                 (xfs_dir2_data_aoff_t)((char *)dup - (char *)data), length,
429                 &needlog, &needscan);
430         /*
431          * Initialize our new entry (at last).
432          */
433         dep = (xfs_dir2_data_entry_t *)dup;
434         INT_SET(dep->inumber, ARCH_CONVERT, args->inumber);
435         dep->namelen = args->namelen;
436         memcpy(dep->name, args->name, dep->namelen);
437         tagp = XFS_DIR2_DATA_ENTRY_TAG_P(dep);
438         INT_SET(*tagp, ARCH_CONVERT, (xfs_dir2_data_off_t)((char *)dep - (char *)data));
439         /*
440          * Need to scan fix up the bestfree table.
441          */
442         if (needscan)
443                 xfs_dir2_data_freescan(mp, data, &needlog, NULL);
444         /*
445          * Need to log the data block's header.
446          */
447         if (needlog)
448                 xfs_dir2_data_log_header(tp, dbp);
449         xfs_dir2_data_log_entry(tp, dbp, dep);
450         /*
451          * If the bests table needs to be changed, do it.
452          * Log the change unless we've already done that.
453          */
454         if (INT_GET(bestsp[use_block], ARCH_CONVERT) != INT_GET(data->hdr.bestfree[0].length, ARCH_CONVERT)) {
455                 INT_COPY(bestsp[use_block], data->hdr.bestfree[0].length, ARCH_CONVERT);
456                 if (!grown)
457                         xfs_dir2_leaf_log_bests(tp, lbp, use_block, use_block);
458         }
459         /*
460          * Now we need to make room to insert the leaf entry.
461          * If there are no stale entries, we just insert a hole at index.
462          */
463         if (!leaf->hdr.stale) {
464                 /*
465                  * lep is still good as the index leaf entry.
466                  */
467                 if (index < INT_GET(leaf->hdr.count, ARCH_CONVERT))
468                         memmove(lep + 1, lep,
469                                 (INT_GET(leaf->hdr.count, ARCH_CONVERT) - index) * sizeof(*lep));
470                 /*
471                  * Record low and high logging indices for the leaf.
472                  */
473                 lfloglow = index;
474                 lfloghigh = INT_GET(leaf->hdr.count, ARCH_CONVERT);
475                 INT_MOD(leaf->hdr.count, ARCH_CONVERT, +1);
476         }
477         /*
478          * There are stale entries.
479          * We will use one of them for the new entry.
480          * It's probably not at the right location, so we'll have to
481          * shift some up or down first.
482          */
483         else {
484                 /*
485                  * If we didn't compact before, we need to find the nearest
486                  * stale entries before and after our insertion point.
487                  */
488                 if (compact == 0) {
489                         /*
490                          * Find the first stale entry before the insertion
491                          * point, if any.
492                          */
493                         for (lowstale = index - 1;
494                              lowstale >= 0 &&
495                                 INT_GET(leaf->ents[lowstale].address, ARCH_CONVERT) !=
496                                 XFS_DIR2_NULL_DATAPTR;
497                              lowstale--)
498                                 continue;
499                         /*
500                          * Find the next stale entry at or after the insertion
501                          * point, if any.   Stop if we go so far that the
502                          * lowstale entry would be better.
503                          */
504                         for (highstale = index;
505                              highstale < INT_GET(leaf->hdr.count, ARCH_CONVERT) &&
506                                 INT_GET(leaf->ents[highstale].address, ARCH_CONVERT) !=
507                                 XFS_DIR2_NULL_DATAPTR &&
508                                 (lowstale < 0 ||
509                                  index - lowstale - 1 >= highstale - index);
510                              highstale++)
511                                 continue;
512                 }
513                 /*
514                  * If the low one is better, use it.
515                  */
516                 if (lowstale >= 0 &&
517                     (highstale == INT_GET(leaf->hdr.count, ARCH_CONVERT) ||
518                      index - lowstale - 1 < highstale - index)) {
519                         ASSERT(index - lowstale - 1 >= 0);
520                         ASSERT(INT_GET(leaf->ents[lowstale].address, ARCH_CONVERT) ==
521                                XFS_DIR2_NULL_DATAPTR);
522                         /*
523                          * Copy entries up to cover the stale entry
524                          * and make room for the new entry.
525                          */
526                         if (index - lowstale - 1 > 0)
527                                 memmove(&leaf->ents[lowstale],
528                                         &leaf->ents[lowstale + 1],
529                                         (index - lowstale - 1) * sizeof(*lep));
530                         lep = &leaf->ents[index - 1];
531                         lfloglow = MIN(lowstale, lfloglow);
532                         lfloghigh = MAX(index - 1, lfloghigh);
533                 }
534                 /*
535                  * The high one is better, so use that one.
536                  */
537                 else {
538                         ASSERT(highstale - index >= 0);
539                         ASSERT(INT_GET(leaf->ents[highstale].address, ARCH_CONVERT) ==
540                                XFS_DIR2_NULL_DATAPTR);
541                         /*
542                          * Copy entries down to copver the stale entry
543                          * and make room for the new entry.
544                          */
545                         if (highstale - index > 0)
546                                 memmove(&leaf->ents[index + 1],
547                                         &leaf->ents[index],
548                                         (highstale - index) * sizeof(*lep));
549                         lep = &leaf->ents[index];
550                         lfloglow = MIN(index, lfloglow);
551                         lfloghigh = MAX(highstale, lfloghigh);
552                 }
553                 INT_MOD(leaf->hdr.stale, ARCH_CONVERT, -1);
554         }
555         /*
556          * Fill in the new leaf entry.
557          */
558         INT_SET(lep->hashval, ARCH_CONVERT, args->hashval);
559         INT_SET(lep->address, ARCH_CONVERT, XFS_DIR2_DB_OFF_TO_DATAPTR(mp, use_block, INT_GET(*tagp, ARCH_CONVERT)));
560         /*
561          * Log the leaf fields and give up the buffers.
562          */
563         xfs_dir2_leaf_log_header(tp, lbp);
564         xfs_dir2_leaf_log_ents(tp, lbp, lfloglow, lfloghigh);
565         xfs_dir2_leaf_check(dp, lbp);
566         xfs_da_buf_done(lbp);
567         xfs_dir2_data_check(dp, dbp);
568         xfs_da_buf_done(dbp);
569         return 0;
570 }
571
572 #ifdef DEBUG
573 /*
574  * Check the internal consistency of a leaf1 block.
575  * Pop an assert if something is wrong.
576  */
577 void
578 xfs_dir2_leaf_check(
579         xfs_inode_t             *dp,            /* incore directory inode */
580         xfs_dabuf_t             *bp)            /* leaf's buffer */
581 {
582         int                     i;              /* leaf index */
583         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
584         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail pointer */
585         xfs_mount_t             *mp;            /* filesystem mount point */
586         int                     stale;          /* count of stale leaves */
587
588         leaf = bp->data;
589         mp = dp->i_mount;
590         ASSERT(INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAF1_MAGIC);
591         /*
592          * This value is not restrictive enough.
593          * Should factor in the size of the bests table as well.
594          * We can deduce a value for that from di_size.
595          */
596         ASSERT(INT_GET(leaf->hdr.count, ARCH_CONVERT) <= XFS_DIR2_MAX_LEAF_ENTS(mp));
597         ltp = XFS_DIR2_LEAF_TAIL_P(mp, leaf);
598         /*
599          * Leaves and bests don't overlap.
600          */
601         ASSERT((char *)&leaf->ents[INT_GET(leaf->hdr.count, ARCH_CONVERT)] <=
602                (char *)XFS_DIR2_LEAF_BESTS_P(ltp));
603         /*
604          * Check hash value order, count stale entries.
605          */
606         for (i = stale = 0; i < INT_GET(leaf->hdr.count, ARCH_CONVERT); i++) {
607                 if (i + 1 < INT_GET(leaf->hdr.count, ARCH_CONVERT))
608                         ASSERT(INT_GET(leaf->ents[i].hashval, ARCH_CONVERT) <=
609                                INT_GET(leaf->ents[i + 1].hashval, ARCH_CONVERT));
610                 if (INT_GET(leaf->ents[i].address, ARCH_CONVERT) == XFS_DIR2_NULL_DATAPTR)
611                         stale++;
612         }
613         ASSERT(INT_GET(leaf->hdr.stale, ARCH_CONVERT) == stale);
614 }
615 #endif  /* DEBUG */
616
617 /*
618  * Compact out any stale entries in the leaf.
619  * Log the header and changed leaf entries, if any.
620  */
621 void
622 xfs_dir2_leaf_compact(
623         xfs_da_args_t   *args,          /* operation arguments */
624         xfs_dabuf_t     *bp)            /* leaf buffer */
625 {
626         int             from;           /* source leaf index */
627         xfs_dir2_leaf_t *leaf;          /* leaf structure */
628         int             loglow;         /* first leaf entry to log */
629         int             to;             /* target leaf index */
630
631         leaf = bp->data;
632         if (!leaf->hdr.stale) {
633                 return;
634         }
635         /*
636          * Compress out the stale entries in place.
637          */
638         for (from = to = 0, loglow = -1; from < INT_GET(leaf->hdr.count, ARCH_CONVERT); from++) {
639                 if (INT_GET(leaf->ents[from].address, ARCH_CONVERT) == XFS_DIR2_NULL_DATAPTR)
640                         continue;
641                 /*
642                  * Only actually copy the entries that are different.
643                  */
644                 if (from > to) {
645                         if (loglow == -1)
646                                 loglow = to;
647                         leaf->ents[to] = leaf->ents[from];
648                 }
649                 to++;
650         }
651         /*
652          * Update and log the header, log the leaf entries.
653          */
654         ASSERT(INT_GET(leaf->hdr.stale, ARCH_CONVERT) == from - to);
655         INT_MOD(leaf->hdr.count, ARCH_CONVERT, -(INT_GET(leaf->hdr.stale, ARCH_CONVERT)));
656         leaf->hdr.stale = 0;
657         xfs_dir2_leaf_log_header(args->trans, bp);
658         if (loglow != -1)
659                 xfs_dir2_leaf_log_ents(args->trans, bp, loglow, to - 1);
660 }
661
662 /*
663  * Compact the leaf entries, removing stale ones.
664  * Leave one stale entry behind - the one closest to our
665  * insertion index - and the caller will shift that one to our insertion
666  * point later.
667  * Return new insertion index, where the remaining stale entry is,
668  * and leaf logging indices.
669  */
670 void
671 xfs_dir2_leaf_compact_x1(
672         xfs_dabuf_t     *bp,            /* leaf buffer */
673         int             *indexp,        /* insertion index */
674         int             *lowstalep,     /* out: stale entry before us */
675         int             *highstalep,    /* out: stale entry after us */
676         int             *lowlogp,       /* out: low log index */
677         int             *highlogp)      /* out: high log index */
678 {
679         int             from;           /* source copy index */
680         int             highstale;      /* stale entry at/after index */
681         int             index;          /* insertion index */
682         int             keepstale;      /* source index of kept stale */
683         xfs_dir2_leaf_t *leaf;          /* leaf structure */
684         int             lowstale;       /* stale entry before index */
685         int             newindex=0;     /* new insertion index */
686         int             to;             /* destination copy index */
687
688         leaf = bp->data;
689         ASSERT(INT_GET(leaf->hdr.stale, ARCH_CONVERT) > 1);
690         index = *indexp;
691         /*
692          * Find the first stale entry before our index, if any.
693          */
694         for (lowstale = index - 1;
695              lowstale >= 0 &&
696                 INT_GET(leaf->ents[lowstale].address, ARCH_CONVERT) != XFS_DIR2_NULL_DATAPTR;
697              lowstale--)
698                 continue;
699         /*
700          * Find the first stale entry at or after our index, if any.
701          * Stop if the answer would be worse than lowstale.
702          */
703         for (highstale = index;
704              highstale < INT_GET(leaf->hdr.count, ARCH_CONVERT) &&
705                 INT_GET(leaf->ents[highstale].address, ARCH_CONVERT) != XFS_DIR2_NULL_DATAPTR &&
706                 (lowstale < 0 || index - lowstale > highstale - index);
707              highstale++)
708                 continue;
709         /*
710          * Pick the better of lowstale and highstale.
711          */
712         if (lowstale >= 0 &&
713             (highstale == INT_GET(leaf->hdr.count, ARCH_CONVERT) ||
714              index - lowstale <= highstale - index))
715                 keepstale = lowstale;
716         else
717                 keepstale = highstale;
718         /*
719          * Copy the entries in place, removing all the stale entries
720          * except keepstale.
721          */
722         for (from = to = 0; from < INT_GET(leaf->hdr.count, ARCH_CONVERT); from++) {
723                 /*
724                  * Notice the new value of index.
725                  */
726                 if (index == from)
727                         newindex = to;
728                 if (from != keepstale &&
729                     INT_GET(leaf->ents[from].address, ARCH_CONVERT) == XFS_DIR2_NULL_DATAPTR) {
730                         if (from == to)
731                                 *lowlogp = to;
732                         continue;
733                 }
734                 /*
735                  * Record the new keepstale value for the insertion.
736                  */
737                 if (from == keepstale)
738                         lowstale = highstale = to;
739                 /*
740                  * Copy only the entries that have moved.
741                  */
742                 if (from > to)
743                         leaf->ents[to] = leaf->ents[from];
744                 to++;
745         }
746         ASSERT(from > to);
747         /*
748          * If the insertion point was past the last entry,
749          * set the new insertion point accordingly.
750          */
751         if (index == from)
752                 newindex = to;
753         *indexp = newindex;
754         /*
755          * Adjust the leaf header values.
756          */
757         INT_MOD(leaf->hdr.count, ARCH_CONVERT, -(from - to));
758         INT_SET(leaf->hdr.stale, ARCH_CONVERT, 1);
759         /*
760          * Remember the low/high stale value only in the "right"
761          * direction.
762          */
763         if (lowstale >= newindex)
764                 lowstale = -1;
765         else
766                 highstale = INT_GET(leaf->hdr.count, ARCH_CONVERT);
767         *highlogp = INT_GET(leaf->hdr.count, ARCH_CONVERT) - 1;
768         *lowstalep = lowstale;
769         *highstalep = highstale;
770 }
771
772 /*
773  * Getdents (readdir) for leaf and node directories.
774  * This reads the data blocks only, so is the same for both forms.
775  */
776 int                                             /* error */
777 xfs_dir2_leaf_getdents(
778         xfs_trans_t             *tp,            /* transaction pointer */
779         xfs_inode_t             *dp,            /* incore directory inode */
780         uio_t                   *uio,           /* I/O control & vectors */
781         int                     *eofp,          /* out: reached end of dir */
782         xfs_dirent_t            *dbp,           /* caller's buffer */
783         xfs_dir2_put_t          put)            /* ABI formatting routine */
784 {
785         xfs_dabuf_t             *bp;            /* data block buffer */
786         int                     byteoff;        /* offset in current block */
787         xfs_dir2_db_t           curdb;          /* db for current block */
788         xfs_dir2_off_t          curoff;         /* current overall offset */
789         xfs_dir2_data_t         *data;          /* data block structure */
790         xfs_dir2_data_entry_t   *dep;           /* data entry */
791         xfs_dir2_data_unused_t  *dup;           /* unused entry */
792         int                     eof;            /* reached end of directory */
793         int                     error=0;                /* error return value */
794         int                     i;              /* temporary loop index */
795         int                     j;              /* temporary loop index */
796         int                     length;         /* temporary length value */
797         xfs_bmbt_irec_t         *map;           /* map vector for blocks */
798         xfs_extlen_t            map_blocks;     /* number of fsbs in map */
799         xfs_dablk_t             map_off;        /* last mapped file offset */
800         int                     map_size;       /* total entries in *map */
801         int                     map_valid;      /* valid entries in *map */
802         xfs_mount_t             *mp;            /* filesystem mount point */
803         xfs_dir2_off_t          newoff;         /* new curoff after new blk */
804         int                     nmap;           /* mappings to ask xfs_bmapi */
805         xfs_dir2_put_args_t     p;              /* formatting arg bundle */
806         char                    *ptr=NULL;              /* pointer to current data */
807         int                     ra_current;     /* number of read-ahead blks */
808         int                     ra_index;       /* *map index for read-ahead */
809         int                     ra_offset;      /* map entry offset for ra */
810         int                     ra_want;        /* readahead count wanted */
811
812         /*
813          * If the offset is at or past the largest allowed value,
814          * give up right away, return eof.
815          */
816         if (uio->uio_offset >= XFS_DIR2_MAX_DATAPTR) {
817                 *eofp = 1;
818                 return 0;
819         }
820         mp = dp->i_mount;
821         /*
822          * Setup formatting arguments.
823          */
824         p.dbp = dbp;
825         p.put = put;
826         p.uio = uio;
827         /*
828          * Set up to bmap a number of blocks based on the caller's
829          * buffer size, the directory block size, and the filesystem
830          * block size.
831          */
832         map_size =
833                 howmany(uio->uio_resid + mp->m_dirblksize,
834                         mp->m_sb.sb_blocksize);
835         map = kmem_alloc(map_size * sizeof(*map), KM_SLEEP);
836         map_valid = ra_index = ra_offset = ra_current = map_blocks = 0;
837         bp = NULL;
838         eof = 1;
839         /*
840          * Inside the loop we keep the main offset value as a byte offset
841          * in the directory file.
842          */
843         curoff = XFS_DIR2_DATAPTR_TO_BYTE(mp, uio->uio_offset);
844         /*
845          * Force this conversion through db so we truncate the offset
846          * down to get the start of the data block.
847          */
848         map_off = XFS_DIR2_DB_TO_DA(mp, XFS_DIR2_BYTE_TO_DB(mp, curoff));
849         /*
850          * Loop over directory entries until we reach the end offset.
851          * Get more blocks and readahead as necessary.
852          */
853         while (curoff < XFS_DIR2_LEAF_OFFSET) {
854                 /*
855                  * If we have no buffer, or we're off the end of the
856                  * current buffer, need to get another one.
857                  */
858                 if (!bp || ptr >= (char *)bp->data + mp->m_dirblksize) {
859                         /*
860                          * If we have a buffer, we need to release it and
861                          * take it out of the mapping.
862                          */
863                         if (bp) {
864                                 xfs_da_brelse(tp, bp);
865                                 bp = NULL;
866                                 map_blocks -= mp->m_dirblkfsbs;
867                                 /*
868                                  * Loop to get rid of the extents for the
869                                  * directory block.
870                                  */
871                                 for (i = mp->m_dirblkfsbs; i > 0; ) {
872                                         j = MIN((int)map->br_blockcount, i);
873                                         map->br_blockcount -= j;
874                                         map->br_startblock += j;
875                                         map->br_startoff += j;
876                                         /*
877                                          * If mapping is done, pitch it from
878                                          * the table.
879                                          */
880                                         if (!map->br_blockcount && --map_valid)
881                                                 memmove(&map[0], &map[1],
882                                                         sizeof(map[0]) *
883                                                         map_valid);
884                                         i -= j;
885                                 }
886                         }
887                         /*
888                          * Recalculate the readahead blocks wanted.
889                          */
890                         ra_want = howmany(uio->uio_resid + mp->m_dirblksize,
891                                           mp->m_sb.sb_blocksize) - 1;
892                         /*
893                          * If we don't have as many as we want, and we haven't
894                          * run out of data blocks, get some more mappings.
895                          */
896                         if (1 + ra_want > map_blocks &&
897                             map_off <
898                             XFS_DIR2_BYTE_TO_DA(mp, XFS_DIR2_LEAF_OFFSET)) {
899                                 /*
900                                  * Get more bmaps, fill in after the ones
901                                  * we already have in the table.
902                                  */
903                                 nmap = map_size - map_valid;
904                                 error = xfs_bmapi(tp, dp,
905                                         map_off,
906                                         XFS_DIR2_BYTE_TO_DA(mp,
907                                                 XFS_DIR2_LEAF_OFFSET) - map_off,
908                                         XFS_BMAPI_METADATA, NULL, 0,
909                                         &map[map_valid], &nmap, NULL);
910                                 /*
911                                  * Don't know if we should ignore this or
912                                  * try to return an error.
913                                  * The trouble with returning errors
914                                  * is that readdir will just stop without
915                                  * actually passing the error through.
916                                  */
917                                 if (error)
918                                         break;  /* XXX */
919                                 /*
920                                  * If we got all the mappings we asked for,
921                                  * set the final map offset based on the
922                                  * last bmap value received.
923                                  * Otherwise, we've reached the end.
924                                  */
925                                 if (nmap == map_size - map_valid)
926                                         map_off =
927                                         map[map_valid + nmap - 1].br_startoff +
928                                         map[map_valid + nmap - 1].br_blockcount;
929                                 else
930                                         map_off =
931                                                 XFS_DIR2_BYTE_TO_DA(mp,
932                                                         XFS_DIR2_LEAF_OFFSET);
933                                 /*
934                                  * Look for holes in the mapping, and
935                                  * eliminate them.  Count up the valid blocks.
936                                  */
937                                 for (i = map_valid; i < map_valid + nmap; ) {
938                                         if (map[i].br_startblock ==
939                                             HOLESTARTBLOCK) {
940                                                 nmap--;
941                                                 length = map_valid + nmap - i;
942                                                 if (length)
943                                                         memmove(&map[i],
944                                                                 &map[i + 1],
945                                                                 sizeof(map[i]) *
946                                                                 length);
947                                         } else {
948                                                 map_blocks +=
949                                                         map[i].br_blockcount;
950                                                 i++;
951                                         }
952                                 }
953                                 map_valid += nmap;
954                         }
955                         /*
956                          * No valid mappings, so no more data blocks.
957                          */
958                         if (!map_valid) {
959                                 curoff = XFS_DIR2_DA_TO_BYTE(mp, map_off);
960                                 break;
961                         }
962                         /*
963                          * Read the directory block starting at the first
964                          * mapping.
965                          */
966                         curdb = XFS_DIR2_DA_TO_DB(mp, map->br_startoff);
967                         error = xfs_da_read_buf(tp, dp, map->br_startoff,
968                                 map->br_blockcount >= mp->m_dirblkfsbs ?
969                                     XFS_FSB_TO_DADDR(mp, map->br_startblock) :
970                                     -1,
971                                 &bp, XFS_DATA_FORK);
972                         /*
973                          * Should just skip over the data block instead
974                          * of giving up.
975                          */
976                         if (error)
977                                 break;  /* XXX */
978                         /*
979                          * Adjust the current amount of read-ahead: we just
980                          * read a block that was previously ra.
981                          */
982                         if (ra_current)
983                                 ra_current -= mp->m_dirblkfsbs;
984                         /*
985                          * Do we need more readahead?
986                          */
987                         for (ra_index = ra_offset = i = 0;
988                              ra_want > ra_current && i < map_blocks;
989                              i += mp->m_dirblkfsbs) {
990                                 ASSERT(ra_index < map_valid);
991                                 /*
992                                  * Read-ahead a contiguous directory block.
993                                  */
994                                 if (i > ra_current &&
995                                     map[ra_index].br_blockcount >=
996                                     mp->m_dirblkfsbs) {
997                                         xfs_baread(mp->m_ddev_targp,
998                                                 XFS_FSB_TO_DADDR(mp,
999                                                    map[ra_index].br_startblock +
1000                                                    ra_offset),
1001                                                 (int)BTOBB(mp->m_dirblksize));
1002                                         ra_current = i;
1003                                 }
1004                                 /*
1005                                  * Read-ahead a non-contiguous directory block.
1006                                  * This doesn't use our mapping, but this
1007                                  * is a very rare case.
1008                                  */
1009                                 else if (i > ra_current) {
1010                                         (void)xfs_da_reada_buf(tp, dp,
1011                                                 map[ra_index].br_startoff +
1012                                                 ra_offset, XFS_DATA_FORK);
1013                                         ra_current = i;
1014                                 }
1015                                 /*
1016                                  * Advance offset through the mapping table.
1017                                  */
1018                                 for (j = 0; j < mp->m_dirblkfsbs; j++) {
1019                                         /*
1020                                          * The rest of this extent but not
1021                                          * more than a dir block.
1022                                          */
1023                                         length = MIN(mp->m_dirblkfsbs,
1024                                                 (int)(map[ra_index].br_blockcount -
1025                                                 ra_offset));
1026                                         j += length;
1027                                         ra_offset += length;
1028                                         /*
1029                                          * Advance to the next mapping if
1030                                          * this one is used up.
1031                                          */
1032                                         if (ra_offset ==
1033                                             map[ra_index].br_blockcount) {
1034                                                 ra_offset = 0;
1035                                                 ra_index++;
1036                                         }
1037                                 }
1038                         }
1039                         /*
1040                          * Having done a read, we need to set a new offset.
1041                          */
1042                         newoff = XFS_DIR2_DB_OFF_TO_BYTE(mp, curdb, 0);
1043                         /*
1044                          * Start of the current block.
1045                          */
1046                         if (curoff < newoff)
1047                                 curoff = newoff;
1048                         /*
1049                          * Make sure we're in the right block.
1050                          */
1051                         else if (curoff > newoff)
1052                                 ASSERT(XFS_DIR2_BYTE_TO_DB(mp, curoff) ==
1053                                        curdb);
1054                         data = bp->data;
1055                         xfs_dir2_data_check(dp, bp);
1056                         /*
1057                          * Find our position in the block.
1058                          */
1059                         ptr = (char *)&data->u;
1060                         byteoff = XFS_DIR2_BYTE_TO_OFF(mp, curoff);
1061                         /*
1062                          * Skip past the header.
1063                          */
1064                         if (byteoff == 0)
1065                                 curoff += (uint)sizeof(data->hdr);
1066                         /*
1067                          * Skip past entries until we reach our offset.
1068                          */
1069                         else {
1070                                 while ((char *)ptr - (char *)data < byteoff) {
1071                                         dup = (xfs_dir2_data_unused_t *)ptr;
1072
1073                                         if (INT_GET(dup->freetag, ARCH_CONVERT)
1074                                                   == XFS_DIR2_DATA_FREE_TAG) {
1075
1076                                                 length = INT_GET(dup->length,
1077                                                                  ARCH_CONVERT);
1078                                                 ptr += length;
1079                                                 continue;
1080                                         }
1081                                         dep = (xfs_dir2_data_entry_t *)ptr;
1082                                         length =
1083                                            XFS_DIR2_DATA_ENTSIZE(dep->namelen);
1084                                         ptr += length;
1085                                 }
1086                                 /*
1087                                  * Now set our real offset.
1088                                  */
1089                                 curoff =
1090                                         XFS_DIR2_DB_OFF_TO_BYTE(mp,
1091                                             XFS_DIR2_BYTE_TO_DB(mp, curoff),
1092                                             (char *)ptr - (char *)data);
1093                                 if (ptr >= (char *)data + mp->m_dirblksize) {
1094                                         continue;
1095                                 }
1096                         }
1097                 }
1098                 /*
1099                  * We have a pointer to an entry.
1100                  * Is it a live one?
1101                  */
1102                 dup = (xfs_dir2_data_unused_t *)ptr;
1103                 /*
1104                  * No, it's unused, skip over it.
1105                  */
1106                 if (INT_GET(dup->freetag, ARCH_CONVERT)
1107                                                 == XFS_DIR2_DATA_FREE_TAG) {
1108                         length = INT_GET(dup->length, ARCH_CONVERT);
1109                         ptr += length;
1110                         curoff += length;
1111                         continue;
1112                 }
1113
1114                 /*
1115                  * Copy the entry into the putargs, and try formatting it.
1116                  */
1117                 dep = (xfs_dir2_data_entry_t *)ptr;
1118
1119                 p.namelen = dep->namelen;
1120
1121                 length = XFS_DIR2_DATA_ENTSIZE(p.namelen);
1122
1123                 p.cook = XFS_DIR2_BYTE_TO_DATAPTR(mp, curoff + length);
1124
1125                 p.ino = INT_GET(dep->inumber, ARCH_CONVERT);
1126 #if XFS_BIG_INUMS
1127                 p.ino += mp->m_inoadd;
1128 #endif
1129                 p.name = (char *)dep->name;
1130
1131                 error = p.put(&p);
1132
1133                 /*
1134                  * Won't fit.  Return to caller.
1135                  */
1136                 if (!p.done) {
1137                         eof = 0;
1138                         break;
1139                 }
1140                 /*
1141                  * Advance to next entry in the block.
1142                  */
1143                 ptr += length;
1144                 curoff += length;
1145         }
1146
1147         /*
1148          * All done.  Set output offset value to current offset.
1149          */
1150         *eofp = eof;
1151         if (curoff > XFS_DIR2_DATAPTR_TO_BYTE(mp, XFS_DIR2_MAX_DATAPTR))
1152                 uio->uio_offset = XFS_DIR2_MAX_DATAPTR;
1153         else
1154                 uio->uio_offset = XFS_DIR2_BYTE_TO_DATAPTR(mp, curoff);
1155         kmem_free(map, map_size * sizeof(*map));
1156         if (bp)
1157                 xfs_da_brelse(tp, bp);
1158         return error;
1159 }
1160
1161 /*
1162  * Initialize a new leaf block, leaf1 or leafn magic accepted.
1163  */
1164 int
1165 xfs_dir2_leaf_init(
1166         xfs_da_args_t           *args,          /* operation arguments */
1167         xfs_dir2_db_t           bno,            /* directory block number */
1168         xfs_dabuf_t             **bpp,          /* out: leaf buffer */
1169         int                     magic)          /* magic number for block */
1170 {
1171         xfs_dabuf_t             *bp;            /* leaf buffer */
1172         xfs_inode_t             *dp;            /* incore directory inode */
1173         int                     error;          /* error return code */
1174         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1175         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1176         xfs_mount_t             *mp;            /* filesystem mount point */
1177         xfs_trans_t             *tp;            /* transaction pointer */
1178
1179         dp = args->dp;
1180         ASSERT(dp != NULL);
1181         tp = args->trans;
1182         mp = dp->i_mount;
1183         ASSERT(bno >= XFS_DIR2_LEAF_FIRSTDB(mp) &&
1184                bno < XFS_DIR2_FREE_FIRSTDB(mp));
1185         /*
1186          * Get the buffer for the block.
1187          */
1188         error = xfs_da_get_buf(tp, dp, XFS_DIR2_DB_TO_DA(mp, bno), -1, &bp,
1189                 XFS_DATA_FORK);
1190         if (error) {
1191                 return error;
1192         }
1193         ASSERT(bp != NULL);
1194         leaf = bp->data;
1195         /*
1196          * Initialize the header.
1197          */
1198         INT_SET(leaf->hdr.info.magic, ARCH_CONVERT, magic);
1199         leaf->hdr.info.forw = 0;
1200         leaf->hdr.info.back = 0;
1201         leaf->hdr.count = 0;
1202         leaf->hdr.stale = 0;
1203         xfs_dir2_leaf_log_header(tp, bp);
1204         /*
1205          * If it's a leaf-format directory initialize the tail.
1206          * In this case our caller has the real bests table to copy into
1207          * the block.
1208          */
1209         if (magic == XFS_DIR2_LEAF1_MAGIC) {
1210                 ltp = XFS_DIR2_LEAF_TAIL_P(mp, leaf);
1211                 ltp->bestcount = 0;
1212                 xfs_dir2_leaf_log_tail(tp, bp);
1213         }
1214         *bpp = bp;
1215         return 0;
1216 }
1217
1218 /*
1219  * Log the bests entries indicated from a leaf1 block.
1220  */
1221 static void
1222 xfs_dir2_leaf_log_bests(
1223         xfs_trans_t             *tp,            /* transaction pointer */
1224         xfs_dabuf_t             *bp,            /* leaf buffer */
1225         int                     first,          /* first entry to log */
1226         int                     last)           /* last entry to log */
1227 {
1228         xfs_dir2_data_off_t     *firstb;        /* pointer to first entry */
1229         xfs_dir2_data_off_t     *lastb;         /* pointer to last entry */
1230         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1231         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1232
1233         leaf = bp->data;
1234         ASSERT(INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAF1_MAGIC);
1235         ltp = XFS_DIR2_LEAF_TAIL_P(tp->t_mountp, leaf);
1236         firstb = XFS_DIR2_LEAF_BESTS_P(ltp) + first;
1237         lastb = XFS_DIR2_LEAF_BESTS_P(ltp) + last;
1238         xfs_da_log_buf(tp, bp, (uint)((char *)firstb - (char *)leaf),
1239                 (uint)((char *)lastb - (char *)leaf + sizeof(*lastb) - 1));
1240 }
1241
1242 /*
1243  * Log the leaf entries indicated from a leaf1 or leafn block.
1244  */
1245 void
1246 xfs_dir2_leaf_log_ents(
1247         xfs_trans_t             *tp,            /* transaction pointer */
1248         xfs_dabuf_t             *bp,            /* leaf buffer */
1249         int                     first,          /* first entry to log */
1250         int                     last)           /* last entry to log */
1251 {
1252         xfs_dir2_leaf_entry_t   *firstlep;      /* pointer to first entry */
1253         xfs_dir2_leaf_entry_t   *lastlep;       /* pointer to last entry */
1254         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1255
1256         leaf = bp->data;
1257         ASSERT(INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAF1_MAGIC ||
1258                INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
1259         firstlep = &leaf->ents[first];
1260         lastlep = &leaf->ents[last];
1261         xfs_da_log_buf(tp, bp, (uint)((char *)firstlep - (char *)leaf),
1262                 (uint)((char *)lastlep - (char *)leaf + sizeof(*lastlep) - 1));
1263 }
1264
1265 /*
1266  * Log the header of the leaf1 or leafn block.
1267  */
1268 void
1269 xfs_dir2_leaf_log_header(
1270         xfs_trans_t             *tp,            /* transaction pointer */
1271         xfs_dabuf_t             *bp)            /* leaf buffer */
1272 {
1273         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1274
1275         leaf = bp->data;
1276         ASSERT(INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAF1_MAGIC ||
1277                INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
1278         xfs_da_log_buf(tp, bp, (uint)((char *)&leaf->hdr - (char *)leaf),
1279                 (uint)(sizeof(leaf->hdr) - 1));
1280 }
1281
1282 /*
1283  * Log the tail of the leaf1 block.
1284  */
1285 STATIC void
1286 xfs_dir2_leaf_log_tail(
1287         xfs_trans_t             *tp,            /* transaction pointer */
1288         xfs_dabuf_t             *bp)            /* leaf buffer */
1289 {
1290         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1291         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1292         xfs_mount_t             *mp;            /* filesystem mount point */
1293
1294         mp = tp->t_mountp;
1295         leaf = bp->data;
1296         ASSERT(INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAF1_MAGIC);
1297         ltp = XFS_DIR2_LEAF_TAIL_P(mp, leaf);
1298         xfs_da_log_buf(tp, bp, (uint)((char *)ltp - (char *)leaf),
1299                 (uint)(mp->m_dirblksize - 1));
1300 }
1301
1302 /*
1303  * Look up the entry referred to by args in the leaf format directory.
1304  * Most of the work is done by the xfs_dir2_leaf_lookup_int routine which
1305  * is also used by the node-format code.
1306  */
1307 int
1308 xfs_dir2_leaf_lookup(
1309         xfs_da_args_t           *args)          /* operation arguments */
1310 {
1311         xfs_dabuf_t             *dbp;           /* data block buffer */
1312         xfs_dir2_data_entry_t   *dep;           /* data block entry */
1313         xfs_inode_t             *dp;            /* incore directory inode */
1314         int                     error;          /* error return code */
1315         int                     index;          /* found entry index */
1316         xfs_dabuf_t             *lbp;           /* leaf buffer */
1317         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1318         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1319         xfs_trans_t             *tp;            /* transaction pointer */
1320
1321         xfs_dir2_trace_args("leaf_lookup", args);
1322         /*
1323          * Look up name in the leaf block, returning both buffers and index.
1324          */
1325         if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1326                 return error;
1327         }
1328         tp = args->trans;
1329         dp = args->dp;
1330         xfs_dir2_leaf_check(dp, lbp);
1331         leaf = lbp->data;
1332         /*
1333          * Get to the leaf entry and contained data entry address.
1334          */
1335         lep = &leaf->ents[index];
1336         /*
1337          * Point to the data entry.
1338          */
1339         dep = (xfs_dir2_data_entry_t *)
1340               ((char *)dbp->data +
1341                XFS_DIR2_DATAPTR_TO_OFF(dp->i_mount, INT_GET(lep->address, ARCH_CONVERT)));
1342         /*
1343          * Return the found inode number.
1344          */
1345         args->inumber = INT_GET(dep->inumber, ARCH_CONVERT);
1346         xfs_da_brelse(tp, dbp);
1347         xfs_da_brelse(tp, lbp);
1348         return XFS_ERROR(EEXIST);
1349 }
1350
1351 /*
1352  * Look up name/hash in the leaf block.
1353  * Fill in indexp with the found index, and dbpp with the data buffer.
1354  * If not found dbpp will be NULL, and ENOENT comes back.
1355  * lbpp will always be filled in with the leaf buffer unless there's an error.
1356  */
1357 static int                                      /* error */
1358 xfs_dir2_leaf_lookup_int(
1359         xfs_da_args_t           *args,          /* operation arguments */
1360         xfs_dabuf_t             **lbpp,         /* out: leaf buffer */
1361         int                     *indexp,        /* out: index in leaf block */
1362         xfs_dabuf_t             **dbpp)         /* out: data buffer */
1363 {
1364         xfs_dir2_db_t           curdb;          /* current data block number */
1365         xfs_dabuf_t             *dbp;           /* data buffer */
1366         xfs_dir2_data_entry_t   *dep;           /* data entry */
1367         xfs_inode_t             *dp;            /* incore directory inode */
1368         int                     error;          /* error return code */
1369         int                     index;          /* index in leaf block */
1370         xfs_dabuf_t             *lbp;           /* leaf buffer */
1371         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1372         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1373         xfs_mount_t             *mp;            /* filesystem mount point */
1374         xfs_dir2_db_t           newdb;          /* new data block number */
1375         xfs_trans_t             *tp;            /* transaction pointer */
1376
1377         dp = args->dp;
1378         tp = args->trans;
1379         mp = dp->i_mount;
1380         /*
1381          * Read the leaf block into the buffer.
1382          */
1383         if ((error =
1384             xfs_da_read_buf(tp, dp, mp->m_dirleafblk, -1, &lbp,
1385                     XFS_DATA_FORK))) {
1386                 return error;
1387         }
1388         *lbpp = lbp;
1389         leaf = lbp->data;
1390         xfs_dir2_leaf_check(dp, lbp);
1391         /*
1392          * Look for the first leaf entry with our hash value.
1393          */
1394         index = xfs_dir2_leaf_search_hash(args, lbp);
1395         /*
1396          * Loop over all the entries with the right hash value
1397          * looking to match the name.
1398          */
1399         for (lep = &leaf->ents[index], dbp = NULL, curdb = -1;
1400              index < INT_GET(leaf->hdr.count, ARCH_CONVERT) && INT_GET(lep->hashval, ARCH_CONVERT) == args->hashval;
1401              lep++, index++) {
1402                 /*
1403                  * Skip over stale leaf entries.
1404                  */
1405                 if (INT_GET(lep->address, ARCH_CONVERT) == XFS_DIR2_NULL_DATAPTR)
1406                         continue;
1407                 /*
1408                  * Get the new data block number.
1409                  */
1410                 newdb = XFS_DIR2_DATAPTR_TO_DB(mp, INT_GET(lep->address, ARCH_CONVERT));
1411                 /*
1412                  * If it's not the same as the old data block number,
1413                  * need to pitch the old one and read the new one.
1414                  */
1415                 if (newdb != curdb) {
1416                         if (dbp)
1417                                 xfs_da_brelse(tp, dbp);
1418                         if ((error =
1419                             xfs_da_read_buf(tp, dp,
1420                                     XFS_DIR2_DB_TO_DA(mp, newdb), -1, &dbp,
1421                                     XFS_DATA_FORK))) {
1422                                 xfs_da_brelse(tp, lbp);
1423                                 return error;
1424                         }
1425                         xfs_dir2_data_check(dp, dbp);
1426                         curdb = newdb;
1427                 }
1428                 /*
1429                  * Point to the data entry.
1430                  */
1431                 dep = (xfs_dir2_data_entry_t *)
1432                       ((char *)dbp->data +
1433                        XFS_DIR2_DATAPTR_TO_OFF(mp, INT_GET(lep->address, ARCH_CONVERT)));
1434                 /*
1435                  * If it matches then return it.
1436                  */
1437                 if (dep->namelen == args->namelen &&
1438                     dep->name[0] == args->name[0] &&
1439                     memcmp(dep->name, args->name, args->namelen) == 0) {
1440                         *dbpp = dbp;
1441                         *indexp = index;
1442                         return 0;
1443                 }
1444         }
1445         /*
1446          * No match found, return ENOENT.
1447          */
1448         ASSERT(args->oknoent);
1449         if (dbp)
1450                 xfs_da_brelse(tp, dbp);
1451         xfs_da_brelse(tp, lbp);
1452         return XFS_ERROR(ENOENT);
1453 }
1454
1455 /*
1456  * Remove an entry from a leaf format directory.
1457  */
1458 int                                             /* error */
1459 xfs_dir2_leaf_removename(
1460         xfs_da_args_t           *args)          /* operation arguments */
1461 {
1462         xfs_dir2_data_off_t     *bestsp;        /* leaf block best freespace */
1463         xfs_dir2_data_t         *data;          /* data block structure */
1464         xfs_dir2_db_t           db;             /* data block number */
1465         xfs_dabuf_t             *dbp;           /* data block buffer */
1466         xfs_dir2_data_entry_t   *dep;           /* data entry structure */
1467         xfs_inode_t             *dp;            /* incore directory inode */
1468         int                     error;          /* error return code */
1469         xfs_dir2_db_t           i;              /* temporary data block # */
1470         int                     index;          /* index into leaf entries */
1471         xfs_dabuf_t             *lbp;           /* leaf buffer */
1472         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1473         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1474         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1475         xfs_mount_t             *mp;            /* filesystem mount point */
1476         int                     needlog;        /* need to log data header */
1477         int                     needscan;       /* need to rescan data frees */
1478         xfs_dir2_data_off_t     oldbest;        /* old value of best free */
1479         xfs_trans_t             *tp;            /* transaction pointer */
1480
1481         xfs_dir2_trace_args("leaf_removename", args);
1482         /*
1483          * Lookup the leaf entry, get the leaf and data blocks read in.
1484          */
1485         if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1486                 return error;
1487         }
1488         dp = args->dp;
1489         tp = args->trans;
1490         mp = dp->i_mount;
1491         leaf = lbp->data;
1492         data = dbp->data;
1493         xfs_dir2_data_check(dp, dbp);
1494         /*
1495          * Point to the leaf entry, use that to point to the data entry.
1496          */
1497         lep = &leaf->ents[index];
1498         db = XFS_DIR2_DATAPTR_TO_DB(mp, INT_GET(lep->address, ARCH_CONVERT));
1499         dep = (xfs_dir2_data_entry_t *)
1500               ((char *)data + XFS_DIR2_DATAPTR_TO_OFF(mp, INT_GET(lep->address, ARCH_CONVERT)));
1501         needscan = needlog = 0;
1502         oldbest = INT_GET(data->hdr.bestfree[0].length, ARCH_CONVERT);
1503         ltp = XFS_DIR2_LEAF_TAIL_P(mp, leaf);
1504         bestsp = XFS_DIR2_LEAF_BESTS_P(ltp);
1505         ASSERT(INT_GET(bestsp[db], ARCH_CONVERT) == oldbest);
1506         /*
1507          * Mark the former data entry unused.
1508          */
1509         xfs_dir2_data_make_free(tp, dbp,
1510                 (xfs_dir2_data_aoff_t)((char *)dep - (char *)data),
1511                 XFS_DIR2_DATA_ENTSIZE(dep->namelen), &needlog, &needscan);
1512         /*
1513          * We just mark the leaf entry stale by putting a null in it.
1514          */
1515         INT_MOD(leaf->hdr.stale, ARCH_CONVERT, +1);
1516         xfs_dir2_leaf_log_header(tp, lbp);
1517         INT_SET(lep->address, ARCH_CONVERT, XFS_DIR2_NULL_DATAPTR);
1518         xfs_dir2_leaf_log_ents(tp, lbp, index, index);
1519         /*
1520          * Scan the freespace in the data block again if necessary,
1521          * log the data block header if necessary.
1522          */
1523         if (needscan)
1524                 xfs_dir2_data_freescan(mp, data, &needlog, NULL);
1525         if (needlog)
1526                 xfs_dir2_data_log_header(tp, dbp);
1527         /*
1528          * If the longest freespace in the data block has changed,
1529          * put the new value in the bests table and log that.
1530          */
1531         if (INT_GET(data->hdr.bestfree[0].length, ARCH_CONVERT) != oldbest) {
1532                 INT_COPY(bestsp[db], data->hdr.bestfree[0].length, ARCH_CONVERT);
1533                 xfs_dir2_leaf_log_bests(tp, lbp, db, db);
1534         }
1535         xfs_dir2_data_check(dp, dbp);
1536         /*
1537          * If the data block is now empty then get rid of the data block.
1538          */
1539         if (INT_GET(data->hdr.bestfree[0].length, ARCH_CONVERT) ==
1540             mp->m_dirblksize - (uint)sizeof(data->hdr)) {
1541                 ASSERT(db != mp->m_dirdatablk);
1542                 if ((error = xfs_dir2_shrink_inode(args, db, dbp))) {
1543                         /*
1544                          * Nope, can't get rid of it because it caused
1545                          * allocation of a bmap btree block to do so.
1546                          * Just go on, returning success, leaving the
1547                          * empty block in place.
1548                          */
1549                         if (error == ENOSPC && args->total == 0) {
1550                                 xfs_da_buf_done(dbp);
1551                                 error = 0;
1552                         }
1553                         xfs_dir2_leaf_check(dp, lbp);
1554                         xfs_da_buf_done(lbp);
1555                         return error;
1556                 }
1557                 dbp = NULL;
1558                 /*
1559                  * If this is the last data block then compact the
1560                  * bests table by getting rid of entries.
1561                  */
1562                 if (db == INT_GET(ltp->bestcount, ARCH_CONVERT) - 1) {
1563                         /*
1564                          * Look for the last active entry (i).
1565                          */
1566                         for (i = db - 1; i > 0; i--) {
1567                                 if (INT_GET(bestsp[i], ARCH_CONVERT) != NULLDATAOFF)
1568                                         break;
1569                         }
1570                         /*
1571                          * Copy the table down so inactive entries at the
1572                          * end are removed.
1573                          */
1574                         memmove(&bestsp[db - i], bestsp,
1575                                 (INT_GET(ltp->bestcount, ARCH_CONVERT) - (db - i)) * sizeof(*bestsp));
1576                         INT_MOD(ltp->bestcount, ARCH_CONVERT, -(db - i));
1577                         xfs_dir2_leaf_log_tail(tp, lbp);
1578                         xfs_dir2_leaf_log_bests(tp, lbp, 0, INT_GET(ltp->bestcount, ARCH_CONVERT) - 1);
1579                 } else
1580                         INT_SET(bestsp[db], ARCH_CONVERT, NULLDATAOFF);
1581         }
1582         /*
1583          * If the data block was not the first one, drop it.
1584          */
1585         else if (db != mp->m_dirdatablk && dbp != NULL) {
1586                 xfs_da_buf_done(dbp);
1587                 dbp = NULL;
1588         }
1589         xfs_dir2_leaf_check(dp, lbp);
1590         /*
1591          * See if we can convert to block form.
1592          */
1593         return xfs_dir2_leaf_to_block(args, lbp, dbp);
1594 }
1595
1596 /*
1597  * Replace the inode number in a leaf format directory entry.
1598  */
1599 int                                             /* error */
1600 xfs_dir2_leaf_replace(
1601         xfs_da_args_t           *args)          /* operation arguments */
1602 {
1603         xfs_dabuf_t             *dbp;           /* data block buffer */
1604         xfs_dir2_data_entry_t   *dep;           /* data block entry */
1605         xfs_inode_t             *dp;            /* incore directory inode */
1606         int                     error;          /* error return code */
1607         int                     index;          /* index of leaf entry */
1608         xfs_dabuf_t             *lbp;           /* leaf buffer */
1609         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1610         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1611         xfs_trans_t             *tp;            /* transaction pointer */
1612
1613         xfs_dir2_trace_args("leaf_replace", args);
1614         /*
1615          * Look up the entry.
1616          */
1617         if ((error = xfs_dir2_leaf_lookup_int(args, &lbp, &index, &dbp))) {
1618                 return error;
1619         }
1620         dp = args->dp;
1621         leaf = lbp->data;
1622         /*
1623          * Point to the leaf entry, get data address from it.
1624          */
1625         lep = &leaf->ents[index];
1626         /*
1627          * Point to the data entry.
1628          */
1629         dep = (xfs_dir2_data_entry_t *)
1630               ((char *)dbp->data +
1631                XFS_DIR2_DATAPTR_TO_OFF(dp->i_mount, INT_GET(lep->address, ARCH_CONVERT)));
1632         ASSERT(args->inumber != INT_GET(dep->inumber, ARCH_CONVERT));
1633         /*
1634          * Put the new inode number in, log it.
1635          */
1636         INT_SET(dep->inumber, ARCH_CONVERT, args->inumber);
1637         tp = args->trans;
1638         xfs_dir2_data_log_entry(tp, dbp, dep);
1639         xfs_da_buf_done(dbp);
1640         xfs_dir2_leaf_check(dp, lbp);
1641         xfs_da_brelse(tp, lbp);
1642         return 0;
1643 }
1644
1645 /*
1646  * Return index in the leaf block (lbp) which is either the first
1647  * one with this hash value, or if there are none, the insert point
1648  * for that hash value.
1649  */
1650 int                                             /* index value */
1651 xfs_dir2_leaf_search_hash(
1652         xfs_da_args_t           *args,          /* operation arguments */
1653         xfs_dabuf_t             *lbp)           /* leaf buffer */
1654 {
1655         xfs_dahash_t            hash=0;         /* hash from this entry */
1656         xfs_dahash_t            hashwant;       /* hash value looking for */
1657         int                     high;           /* high leaf index */
1658         int                     low;            /* low leaf index */
1659         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1660         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
1661         int                     mid=0;          /* current leaf index */
1662
1663         leaf = lbp->data;
1664 #ifndef __KERNEL__
1665         if (!leaf->hdr.count)
1666                 return 0;
1667 #endif
1668         /*
1669          * Note, the table cannot be empty, so we have to go through the loop.
1670          * Binary search the leaf entries looking for our hash value.
1671          */
1672         for (lep = leaf->ents, low = 0, high = INT_GET(leaf->hdr.count, ARCH_CONVERT) - 1,
1673                 hashwant = args->hashval;
1674              low <= high; ) {
1675                 mid = (low + high) >> 1;
1676                 if ((hash = INT_GET(lep[mid].hashval, ARCH_CONVERT)) == hashwant)
1677                         break;
1678                 if (hash < hashwant)
1679                         low = mid + 1;
1680                 else
1681                         high = mid - 1;
1682         }
1683         /*
1684          * Found one, back up through all the equal hash values.
1685          */
1686         if (hash == hashwant) {
1687                 while (mid > 0 && INT_GET(lep[mid - 1].hashval, ARCH_CONVERT) == hashwant) {
1688                         mid--;
1689                 }
1690         }
1691         /*
1692          * Need to point to an entry higher than ours.
1693          */
1694         else if (hash < hashwant)
1695                 mid++;
1696         return mid;
1697 }
1698
1699 /*
1700  * Trim off a trailing data block.  We know it's empty since the leaf
1701  * freespace table says so.
1702  */
1703 int                                             /* error */
1704 xfs_dir2_leaf_trim_data(
1705         xfs_da_args_t           *args,          /* operation arguments */
1706         xfs_dabuf_t             *lbp,           /* leaf buffer */
1707         xfs_dir2_db_t           db)             /* data block number */
1708 {
1709         xfs_dir2_data_off_t     *bestsp;        /* leaf bests table */
1710 #ifdef DEBUG
1711         xfs_dir2_data_t         *data;          /* data block structure */
1712 #endif
1713         xfs_dabuf_t             *dbp;           /* data block buffer */
1714         xfs_inode_t             *dp;            /* incore directory inode */
1715         int                     error;          /* error return value */
1716         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1717         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
1718         xfs_mount_t             *mp;            /* filesystem mount point */
1719         xfs_trans_t             *tp;            /* transaction pointer */
1720
1721         dp = args->dp;
1722         mp = dp->i_mount;
1723         tp = args->trans;
1724         /*
1725          * Read the offending data block.  We need its buffer.
1726          */
1727         if ((error = xfs_da_read_buf(tp, dp, XFS_DIR2_DB_TO_DA(mp, db), -1, &dbp,
1728                         XFS_DATA_FORK))) {
1729                 return error;
1730         }
1731 #ifdef DEBUG
1732         data = dbp->data;
1733         ASSERT(INT_GET(data->hdr.magic, ARCH_CONVERT) == XFS_DIR2_DATA_MAGIC);
1734 #endif
1735         /* this seems to be an error
1736          * data is only valid if DEBUG is defined?
1737          * RMC 09/08/1999
1738          */
1739
1740         leaf = lbp->data;
1741         ltp = XFS_DIR2_LEAF_TAIL_P(mp, leaf);
1742         ASSERT(INT_GET(data->hdr.bestfree[0].length, ARCH_CONVERT) ==
1743                mp->m_dirblksize - (uint)sizeof(data->hdr));
1744         ASSERT(db == INT_GET(ltp->bestcount, ARCH_CONVERT) - 1);
1745         /*
1746          * Get rid of the data block.
1747          */
1748         if ((error = xfs_dir2_shrink_inode(args, db, dbp))) {
1749                 ASSERT(error != ENOSPC);
1750                 xfs_da_brelse(tp, dbp);
1751                 return error;
1752         }
1753         /*
1754          * Eliminate the last bests entry from the table.
1755          */
1756         bestsp = XFS_DIR2_LEAF_BESTS_P(ltp);
1757         INT_MOD(ltp->bestcount, ARCH_CONVERT, -1);
1758         memmove(&bestsp[1], &bestsp[0], INT_GET(ltp->bestcount, ARCH_CONVERT) * sizeof(*bestsp));
1759         xfs_dir2_leaf_log_tail(tp, lbp);
1760         xfs_dir2_leaf_log_bests(tp, lbp, 0, INT_GET(ltp->bestcount, ARCH_CONVERT) - 1);
1761         return 0;
1762 }
1763
1764 /*
1765  * Convert node form directory to leaf form directory.
1766  * The root of the node form dir needs to already be a LEAFN block.
1767  * Just return if we can't do anything.
1768  */
1769 int                                             /* error */
1770 xfs_dir2_node_to_leaf(
1771         xfs_da_state_t          *state)         /* directory operation state */
1772 {
1773         xfs_da_args_t           *args;          /* operation arguments */
1774         xfs_inode_t             *dp;            /* incore directory inode */
1775         int                     error;          /* error return code */
1776         xfs_dabuf_t             *fbp;           /* buffer for freespace block */
1777         xfs_fileoff_t           fo;             /* freespace file offset */
1778         xfs_dir2_free_t         *free;          /* freespace structure */
1779         xfs_dabuf_t             *lbp;           /* buffer for leaf block */
1780         xfs_dir2_leaf_tail_t    *ltp;           /* tail of leaf structure */
1781         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1782         xfs_mount_t             *mp;            /* filesystem mount point */
1783         int                     rval;           /* successful free trim? */
1784         xfs_trans_t             *tp;            /* transaction pointer */
1785
1786         /*
1787          * There's more than a leaf level in the btree, so there must
1788          * be multiple leafn blocks.  Give up.
1789          */
1790         if (state->path.active > 1)
1791                 return 0;
1792         args = state->args;
1793         xfs_dir2_trace_args("node_to_leaf", args);
1794         mp = state->mp;
1795         dp = args->dp;
1796         tp = args->trans;
1797         /*
1798          * Get the last offset in the file.
1799          */
1800         if ((error = xfs_bmap_last_offset(tp, dp, &fo, XFS_DATA_FORK))) {
1801                 return error;
1802         }
1803         fo -= mp->m_dirblkfsbs;
1804         /*
1805          * If there are freespace blocks other than the first one,
1806          * take this opportunity to remove trailing empty freespace blocks
1807          * that may have been left behind during no-space-reservation
1808          * operations.
1809          */
1810         while (fo > mp->m_dirfreeblk) {
1811                 if ((error = xfs_dir2_node_trim_free(args, fo, &rval))) {
1812                         return error;
1813                 }
1814                 if (rval)
1815                         fo -= mp->m_dirblkfsbs;
1816                 else
1817                         return 0;
1818         }
1819         /*
1820          * Now find the block just before the freespace block.
1821          */
1822         if ((error = xfs_bmap_last_before(tp, dp, &fo, XFS_DATA_FORK))) {
1823                 return error;
1824         }
1825         /*
1826          * If it's not the single leaf block, give up.
1827          */
1828         if (XFS_FSB_TO_B(mp, fo) > XFS_DIR2_LEAF_OFFSET + mp->m_dirblksize)
1829                 return 0;
1830         lbp = state->path.blk[0].bp;
1831         leaf = lbp->data;
1832         ASSERT(INT_GET(leaf->hdr.info.magic, ARCH_CONVERT) == XFS_DIR2_LEAFN_MAGIC);
1833         /*
1834          * Read the freespace block.
1835          */
1836         if ((error = xfs_da_read_buf(tp, dp, mp->m_dirfreeblk, -1, &fbp,
1837                         XFS_DATA_FORK))) {
1838                 return error;
1839         }
1840         free = fbp->data;
1841         ASSERT(INT_GET(free->hdr.magic, ARCH_CONVERT) == XFS_DIR2_FREE_MAGIC);
1842         ASSERT(!free->hdr.firstdb);
1843         /*
1844          * Now see if the leafn and free data will fit in a leaf1.
1845          * If not, release the buffer and give up.
1846          */
1847         if ((uint)sizeof(leaf->hdr) +
1848             (INT_GET(leaf->hdr.count, ARCH_CONVERT) - INT_GET(leaf->hdr.stale, ARCH_CONVERT)) * (uint)sizeof(leaf->ents[0]) +
1849             INT_GET(free->hdr.nvalid, ARCH_CONVERT) * (uint)sizeof(leaf->bests[0]) +
1850             (uint)sizeof(leaf->tail) >
1851             mp->m_dirblksize) {
1852                 xfs_da_brelse(tp, fbp);
1853                 return 0;
1854         }
1855         /*
1856          * If the leaf has any stale entries in it, compress them out.
1857          * The compact routine will log the header.
1858          */
1859         if (INT_GET(leaf->hdr.stale, ARCH_CONVERT))
1860                 xfs_dir2_leaf_compact(args, lbp);
1861         else
1862                 xfs_dir2_leaf_log_header(tp, lbp);
1863         INT_SET(leaf->hdr.info.magic, ARCH_CONVERT, XFS_DIR2_LEAF1_MAGIC);
1864         /*
1865          * Set up the leaf tail from the freespace block.
1866          */
1867         ltp = XFS_DIR2_LEAF_TAIL_P(mp, leaf);
1868         INT_COPY(ltp->bestcount, free->hdr.nvalid, ARCH_CONVERT);
1869         /*
1870          * Set up the leaf bests table.
1871          */
1872         memcpy(XFS_DIR2_LEAF_BESTS_P(ltp), free->bests,
1873                 INT_GET(ltp->bestcount, ARCH_CONVERT) * sizeof(leaf->bests[0]));
1874         xfs_dir2_leaf_log_bests(tp, lbp, 0, INT_GET(ltp->bestcount, ARCH_CONVERT) - 1);
1875         xfs_dir2_leaf_log_tail(tp, lbp);
1876         xfs_dir2_leaf_check(dp, lbp);
1877         /*
1878          * Get rid of the freespace block.
1879          */
1880         error = xfs_dir2_shrink_inode(args, XFS_DIR2_FREE_FIRSTDB(mp), fbp);
1881         if (error) {
1882                 /*
1883                  * This can't fail here because it can only happen when
1884                  * punching out the middle of an extent, and this is an
1885                  * isolated block.
1886                  */
1887                 ASSERT(error != ENOSPC);
1888                 return error;
1889         }
1890         fbp = NULL;
1891         /*
1892          * Now see if we can convert the single-leaf directory
1893          * down to a block form directory.
1894          * This routine always kills the dabuf for the leaf, so
1895          * eliminate it from the path.
1896          */
1897         error = xfs_dir2_leaf_to_block(args, lbp, NULL);
1898         state->path.blk[0].bp = NULL;
1899         return error;
1900 }