Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-2.6.git] / fs / xfs / xfs_dir2_node.c
1 /*
2  * Copyright (c) 2000-2005 Silicon Graphics, Inc.
3  * All Rights Reserved.
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it would be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write the Free Software Foundation,
16  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
17  */
18 #include "xfs.h"
19 #include "xfs_fs.h"
20 #include "xfs_types.h"
21 #include "xfs_log.h"
22 #include "xfs_inum.h"
23 #include "xfs_trans.h"
24 #include "xfs_sb.h"
25 #include "xfs_ag.h"
26 #include "xfs_mount.h"
27 #include "xfs_da_btree.h"
28 #include "xfs_bmap_btree.h"
29 #include "xfs_dinode.h"
30 #include "xfs_inode.h"
31 #include "xfs_bmap.h"
32 #include "xfs_dir2_format.h"
33 #include "xfs_dir2_priv.h"
34 #include "xfs_error.h"
35 #include "xfs_trace.h"
36
37 /*
38  * Function declarations.
39  */
40 static void xfs_dir2_free_log_header(xfs_trans_t *tp, xfs_dabuf_t *bp);
41 static int xfs_dir2_leafn_add(xfs_dabuf_t *bp, xfs_da_args_t *args, int index);
42 #ifdef DEBUG
43 static void xfs_dir2_leafn_check(xfs_inode_t *dp, xfs_dabuf_t *bp);
44 #else
45 #define xfs_dir2_leafn_check(dp, bp)
46 #endif
47 static void xfs_dir2_leafn_moveents(xfs_da_args_t *args, xfs_dabuf_t *bp_s,
48                                     int start_s, xfs_dabuf_t *bp_d, int start_d,
49                                     int count);
50 static void xfs_dir2_leafn_rebalance(xfs_da_state_t *state,
51                                      xfs_da_state_blk_t *blk1,
52                                      xfs_da_state_blk_t *blk2);
53 static int xfs_dir2_leafn_remove(xfs_da_args_t *args, xfs_dabuf_t *bp,
54                                  int index, xfs_da_state_blk_t *dblk,
55                                  int *rval);
56 static int xfs_dir2_node_addname_int(xfs_da_args_t *args,
57                                      xfs_da_state_blk_t *fblk);
58
59 /*
60  * Log entries from a freespace block.
61  */
62 STATIC void
63 xfs_dir2_free_log_bests(
64         xfs_trans_t             *tp,            /* transaction pointer */
65         xfs_dabuf_t             *bp,            /* freespace buffer */
66         int                     first,          /* first entry to log */
67         int                     last)           /* last entry to log */
68 {
69         xfs_dir2_free_t         *free;          /* freespace structure */
70
71         free = bp->data;
72         ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
73         xfs_da_log_buf(tp, bp,
74                 (uint)((char *)&free->bests[first] - (char *)free),
75                 (uint)((char *)&free->bests[last] - (char *)free +
76                        sizeof(free->bests[0]) - 1));
77 }
78
79 /*
80  * Log header from a freespace block.
81  */
82 static void
83 xfs_dir2_free_log_header(
84         xfs_trans_t             *tp,            /* transaction pointer */
85         xfs_dabuf_t             *bp)            /* freespace buffer */
86 {
87         xfs_dir2_free_t         *free;          /* freespace structure */
88
89         free = bp->data;
90         ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
91         xfs_da_log_buf(tp, bp, (uint)((char *)&free->hdr - (char *)free),
92                 (uint)(sizeof(xfs_dir2_free_hdr_t) - 1));
93 }
94
95 /*
96  * Convert a leaf-format directory to a node-format directory.
97  * We need to change the magic number of the leaf block, and copy
98  * the freespace table out of the leaf block into its own block.
99  */
100 int                                             /* error */
101 xfs_dir2_leaf_to_node(
102         xfs_da_args_t           *args,          /* operation arguments */
103         xfs_dabuf_t             *lbp)           /* leaf buffer */
104 {
105         xfs_inode_t             *dp;            /* incore directory inode */
106         int                     error;          /* error return value */
107         xfs_dabuf_t             *fbp;           /* freespace buffer */
108         xfs_dir2_db_t           fdb;            /* freespace block number */
109         xfs_dir2_free_t         *free;          /* freespace structure */
110         __be16                  *from;          /* pointer to freespace entry */
111         int                     i;              /* leaf freespace index */
112         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
113         xfs_dir2_leaf_tail_t    *ltp;           /* leaf tail structure */
114         xfs_mount_t             *mp;            /* filesystem mount point */
115         int                     n;              /* count of live freespc ents */
116         xfs_dir2_data_off_t     off;            /* freespace entry value */
117         __be16                  *to;            /* pointer to freespace entry */
118         xfs_trans_t             *tp;            /* transaction pointer */
119
120         trace_xfs_dir2_leaf_to_node(args);
121
122         dp = args->dp;
123         mp = dp->i_mount;
124         tp = args->trans;
125         /*
126          * Add a freespace block to the directory.
127          */
128         if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_FREE_SPACE, &fdb))) {
129                 return error;
130         }
131         ASSERT(fdb == XFS_DIR2_FREE_FIRSTDB(mp));
132         /*
133          * Get the buffer for the new freespace block.
134          */
135         if ((error = xfs_da_get_buf(tp, dp, xfs_dir2_db_to_da(mp, fdb), -1, &fbp,
136                         XFS_DATA_FORK))) {
137                 return error;
138         }
139         ASSERT(fbp != NULL);
140         free = fbp->data;
141         leaf = lbp->data;
142         ltp = xfs_dir2_leaf_tail_p(mp, leaf);
143         /*
144          * Initialize the freespace block header.
145          */
146         free->hdr.magic = cpu_to_be32(XFS_DIR2_FREE_MAGIC);
147         free->hdr.firstdb = 0;
148         ASSERT(be32_to_cpu(ltp->bestcount) <= (uint)dp->i_d.di_size / mp->m_dirblksize);
149         free->hdr.nvalid = ltp->bestcount;
150         /*
151          * Copy freespace entries from the leaf block to the new block.
152          * Count active entries.
153          */
154         for (i = n = 0, from = xfs_dir2_leaf_bests_p(ltp), to = free->bests;
155              i < be32_to_cpu(ltp->bestcount); i++, from++, to++) {
156                 if ((off = be16_to_cpu(*from)) != NULLDATAOFF)
157                         n++;
158                 *to = cpu_to_be16(off);
159         }
160         free->hdr.nused = cpu_to_be32(n);
161         leaf->hdr.info.magic = cpu_to_be16(XFS_DIR2_LEAFN_MAGIC);
162         /*
163          * Log everything.
164          */
165         xfs_dir2_leaf_log_header(tp, lbp);
166         xfs_dir2_free_log_header(tp, fbp);
167         xfs_dir2_free_log_bests(tp, fbp, 0, be32_to_cpu(free->hdr.nvalid) - 1);
168         xfs_da_buf_done(fbp);
169         xfs_dir2_leafn_check(dp, lbp);
170         return 0;
171 }
172
173 /*
174  * Add a leaf entry to a leaf block in a node-form directory.
175  * The other work necessary is done from the caller.
176  */
177 static int                                      /* error */
178 xfs_dir2_leafn_add(
179         xfs_dabuf_t             *bp,            /* leaf buffer */
180         xfs_da_args_t           *args,          /* operation arguments */
181         int                     index)          /* insertion pt for new entry */
182 {
183         int                     compact;        /* compacting stale leaves */
184         xfs_inode_t             *dp;            /* incore directory inode */
185         int                     highstale;      /* next stale entry */
186         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
187         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
188         int                     lfloghigh;      /* high leaf entry logging */
189         int                     lfloglow;       /* low leaf entry logging */
190         int                     lowstale;       /* previous stale entry */
191         xfs_mount_t             *mp;            /* filesystem mount point */
192         xfs_trans_t             *tp;            /* transaction pointer */
193
194         trace_xfs_dir2_leafn_add(args, index);
195
196         dp = args->dp;
197         mp = dp->i_mount;
198         tp = args->trans;
199         leaf = bp->data;
200
201         /*
202          * Quick check just to make sure we are not going to index
203          * into other peoples memory
204          */
205         if (index < 0)
206                 return XFS_ERROR(EFSCORRUPTED);
207
208         /*
209          * If there are already the maximum number of leaf entries in
210          * the block, if there are no stale entries it won't fit.
211          * Caller will do a split.  If there are stale entries we'll do
212          * a compact.
213          */
214
215         if (be16_to_cpu(leaf->hdr.count) == xfs_dir2_max_leaf_ents(mp)) {
216                 if (!leaf->hdr.stale)
217                         return XFS_ERROR(ENOSPC);
218                 compact = be16_to_cpu(leaf->hdr.stale) > 1;
219         } else
220                 compact = 0;
221         ASSERT(index == 0 || be32_to_cpu(leaf->ents[index - 1].hashval) <= args->hashval);
222         ASSERT(index == be16_to_cpu(leaf->hdr.count) ||
223                be32_to_cpu(leaf->ents[index].hashval) >= args->hashval);
224
225         if (args->op_flags & XFS_DA_OP_JUSTCHECK)
226                 return 0;
227
228         /*
229          * Compact out all but one stale leaf entry.  Leaves behind
230          * the entry closest to index.
231          */
232         if (compact) {
233                 xfs_dir2_leaf_compact_x1(bp, &index, &lowstale, &highstale,
234                         &lfloglow, &lfloghigh);
235         }
236         /*
237          * Set impossible logging indices for this case.
238          */
239         else if (leaf->hdr.stale) {
240                 lfloglow = be16_to_cpu(leaf->hdr.count);
241                 lfloghigh = -1;
242         }
243
244         /*
245          * Insert the new entry, log everything.
246          */
247         lep = xfs_dir2_leaf_find_entry(leaf, index, compact, lowstale,
248                                        highstale, &lfloglow, &lfloghigh);
249
250         lep->hashval = cpu_to_be32(args->hashval);
251         lep->address = cpu_to_be32(xfs_dir2_db_off_to_dataptr(mp,
252                                 args->blkno, args->index));
253         xfs_dir2_leaf_log_header(tp, bp);
254         xfs_dir2_leaf_log_ents(tp, bp, lfloglow, lfloghigh);
255         xfs_dir2_leafn_check(dp, bp);
256         return 0;
257 }
258
259 #ifdef DEBUG
260 /*
261  * Check internal consistency of a leafn block.
262  */
263 void
264 xfs_dir2_leafn_check(
265         xfs_inode_t     *dp,                    /* incore directory inode */
266         xfs_dabuf_t     *bp)                    /* leaf buffer */
267 {
268         int             i;                      /* leaf index */
269         xfs_dir2_leaf_t *leaf;                  /* leaf structure */
270         xfs_mount_t     *mp;                    /* filesystem mount point */
271         int             stale;                  /* count of stale leaves */
272
273         leaf = bp->data;
274         mp = dp->i_mount;
275         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
276         ASSERT(be16_to_cpu(leaf->hdr.count) <= xfs_dir2_max_leaf_ents(mp));
277         for (i = stale = 0; i < be16_to_cpu(leaf->hdr.count); i++) {
278                 if (i + 1 < be16_to_cpu(leaf->hdr.count)) {
279                         ASSERT(be32_to_cpu(leaf->ents[i].hashval) <=
280                                be32_to_cpu(leaf->ents[i + 1].hashval));
281                 }
282                 if (leaf->ents[i].address == cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
283                         stale++;
284         }
285         ASSERT(be16_to_cpu(leaf->hdr.stale) == stale);
286 }
287 #endif  /* DEBUG */
288
289 /*
290  * Return the last hash value in the leaf.
291  * Stale entries are ok.
292  */
293 xfs_dahash_t                                    /* hash value */
294 xfs_dir2_leafn_lasthash(
295         xfs_dabuf_t     *bp,                    /* leaf buffer */
296         int             *count)                 /* count of entries in leaf */
297 {
298         xfs_dir2_leaf_t *leaf;                  /* leaf structure */
299
300         leaf = bp->data;
301         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
302         if (count)
303                 *count = be16_to_cpu(leaf->hdr.count);
304         if (!leaf->hdr.count)
305                 return 0;
306         return be32_to_cpu(leaf->ents[be16_to_cpu(leaf->hdr.count) - 1].hashval);
307 }
308
309 /*
310  * Look up a leaf entry for space to add a name in a node-format leaf block.
311  * The extrablk in state is a freespace block.
312  */
313 STATIC int
314 xfs_dir2_leafn_lookup_for_addname(
315         xfs_dabuf_t             *bp,            /* leaf buffer */
316         xfs_da_args_t           *args,          /* operation arguments */
317         int                     *indexp,        /* out: leaf entry index */
318         xfs_da_state_t          *state)         /* state to fill in */
319 {
320         xfs_dabuf_t             *curbp = NULL;  /* current data/free buffer */
321         xfs_dir2_db_t           curdb = -1;     /* current data block number */
322         xfs_dir2_db_t           curfdb = -1;    /* current free block number */
323         xfs_inode_t             *dp;            /* incore directory inode */
324         int                     error;          /* error return value */
325         int                     fi;             /* free entry index */
326         xfs_dir2_free_t         *free = NULL;   /* free block structure */
327         int                     index;          /* leaf entry index */
328         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
329         int                     length;         /* length of new data entry */
330         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
331         xfs_mount_t             *mp;            /* filesystem mount point */
332         xfs_dir2_db_t           newdb;          /* new data block number */
333         xfs_dir2_db_t           newfdb;         /* new free block number */
334         xfs_trans_t             *tp;            /* transaction pointer */
335
336         dp = args->dp;
337         tp = args->trans;
338         mp = dp->i_mount;
339         leaf = bp->data;
340         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
341 #ifdef __KERNEL__
342         ASSERT(be16_to_cpu(leaf->hdr.count) > 0);
343 #endif
344         xfs_dir2_leafn_check(dp, bp);
345         /*
346          * Look up the hash value in the leaf entries.
347          */
348         index = xfs_dir2_leaf_search_hash(args, bp);
349         /*
350          * Do we have a buffer coming in?
351          */
352         if (state->extravalid) {
353                 /* If so, it's a free block buffer, get the block number. */
354                 curbp = state->extrablk.bp;
355                 curfdb = state->extrablk.blkno;
356                 free = curbp->data;
357                 ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
358         }
359         length = xfs_dir2_data_entsize(args->namelen);
360         /*
361          * Loop over leaf entries with the right hash value.
362          */
363         for (lep = &leaf->ents[index]; index < be16_to_cpu(leaf->hdr.count) &&
364                                 be32_to_cpu(lep->hashval) == args->hashval;
365                                 lep++, index++) {
366                 /*
367                  * Skip stale leaf entries.
368                  */
369                 if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
370                         continue;
371                 /*
372                  * Pull the data block number from the entry.
373                  */
374                 newdb = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
375                 /*
376                  * For addname, we're looking for a place to put the new entry.
377                  * We want to use a data block with an entry of equal
378                  * hash value to ours if there is one with room.
379                  *
380                  * If this block isn't the data block we already have
381                  * in hand, take a look at it.
382                  */
383                 if (newdb != curdb) {
384                         curdb = newdb;
385                         /*
386                          * Convert the data block to the free block
387                          * holding its freespace information.
388                          */
389                         newfdb = xfs_dir2_db_to_fdb(mp, newdb);
390                         /*
391                          * If it's not the one we have in hand, read it in.
392                          */
393                         if (newfdb != curfdb) {
394                                 /*
395                                  * If we had one before, drop it.
396                                  */
397                                 if (curbp)
398                                         xfs_da_brelse(tp, curbp);
399                                 /*
400                                  * Read the free block.
401                                  */
402                                 error = xfs_da_read_buf(tp, dp,
403                                                 xfs_dir2_db_to_da(mp, newfdb),
404                                                 -1, &curbp, XFS_DATA_FORK);
405                                 if (error)
406                                         return error;
407                                 free = curbp->data;
408                                 ASSERT(be32_to_cpu(free->hdr.magic) ==
409                                         XFS_DIR2_FREE_MAGIC);
410                                 ASSERT((be32_to_cpu(free->hdr.firstdb) %
411                                         xfs_dir2_free_max_bests(mp)) == 0);
412                                 ASSERT(be32_to_cpu(free->hdr.firstdb) <= curdb);
413                                 ASSERT(curdb < be32_to_cpu(free->hdr.firstdb) +
414                                         be32_to_cpu(free->hdr.nvalid));
415                         }
416                         /*
417                          * Get the index for our entry.
418                          */
419                         fi = xfs_dir2_db_to_fdindex(mp, curdb);
420                         /*
421                          * If it has room, return it.
422                          */
423                         if (unlikely(free->bests[fi] ==
424                             cpu_to_be16(NULLDATAOFF))) {
425                                 XFS_ERROR_REPORT("xfs_dir2_leafn_lookup_int",
426                                                         XFS_ERRLEVEL_LOW, mp);
427                                 if (curfdb != newfdb)
428                                         xfs_da_brelse(tp, curbp);
429                                 return XFS_ERROR(EFSCORRUPTED);
430                         }
431                         curfdb = newfdb;
432                         if (be16_to_cpu(free->bests[fi]) >= length)
433                                 goto out;
434                 }
435         }
436         /* Didn't find any space */
437         fi = -1;
438 out:
439         ASSERT(args->op_flags & XFS_DA_OP_OKNOENT);
440         if (curbp) {
441                 /* Giving back a free block. */
442                 state->extravalid = 1;
443                 state->extrablk.bp = curbp;
444                 state->extrablk.index = fi;
445                 state->extrablk.blkno = curfdb;
446                 state->extrablk.magic = XFS_DIR2_FREE_MAGIC;
447         } else {
448                 state->extravalid = 0;
449         }
450         /*
451          * Return the index, that will be the insertion point.
452          */
453         *indexp = index;
454         return XFS_ERROR(ENOENT);
455 }
456
457 /*
458  * Look up a leaf entry in a node-format leaf block.
459  * The extrablk in state a data block.
460  */
461 STATIC int
462 xfs_dir2_leafn_lookup_for_entry(
463         xfs_dabuf_t             *bp,            /* leaf buffer */
464         xfs_da_args_t           *args,          /* operation arguments */
465         int                     *indexp,        /* out: leaf entry index */
466         xfs_da_state_t          *state)         /* state to fill in */
467 {
468         xfs_dabuf_t             *curbp = NULL;  /* current data/free buffer */
469         xfs_dir2_db_t           curdb = -1;     /* current data block number */
470         xfs_dir2_data_entry_t   *dep;           /* data block entry */
471         xfs_inode_t             *dp;            /* incore directory inode */
472         int                     error;          /* error return value */
473         int                     index;          /* leaf entry index */
474         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
475         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
476         xfs_mount_t             *mp;            /* filesystem mount point */
477         xfs_dir2_db_t           newdb;          /* new data block number */
478         xfs_trans_t             *tp;            /* transaction pointer */
479         enum xfs_dacmp          cmp;            /* comparison result */
480
481         dp = args->dp;
482         tp = args->trans;
483         mp = dp->i_mount;
484         leaf = bp->data;
485         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
486 #ifdef __KERNEL__
487         ASSERT(be16_to_cpu(leaf->hdr.count) > 0);
488 #endif
489         xfs_dir2_leafn_check(dp, bp);
490         /*
491          * Look up the hash value in the leaf entries.
492          */
493         index = xfs_dir2_leaf_search_hash(args, bp);
494         /*
495          * Do we have a buffer coming in?
496          */
497         if (state->extravalid) {
498                 curbp = state->extrablk.bp;
499                 curdb = state->extrablk.blkno;
500         }
501         /*
502          * Loop over leaf entries with the right hash value.
503          */
504         for (lep = &leaf->ents[index]; index < be16_to_cpu(leaf->hdr.count) &&
505                                 be32_to_cpu(lep->hashval) == args->hashval;
506                                 lep++, index++) {
507                 /*
508                  * Skip stale leaf entries.
509                  */
510                 if (be32_to_cpu(lep->address) == XFS_DIR2_NULL_DATAPTR)
511                         continue;
512                 /*
513                  * Pull the data block number from the entry.
514                  */
515                 newdb = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
516                 /*
517                  * Not adding a new entry, so we really want to find
518                  * the name given to us.
519                  *
520                  * If it's a different data block, go get it.
521                  */
522                 if (newdb != curdb) {
523                         /*
524                          * If we had a block before that we aren't saving
525                          * for a CI name, drop it
526                          */
527                         if (curbp && (args->cmpresult == XFS_CMP_DIFFERENT ||
528                                                 curdb != state->extrablk.blkno))
529                                 xfs_da_brelse(tp, curbp);
530                         /*
531                          * If needing the block that is saved with a CI match,
532                          * use it otherwise read in the new data block.
533                          */
534                         if (args->cmpresult != XFS_CMP_DIFFERENT &&
535                                         newdb == state->extrablk.blkno) {
536                                 ASSERT(state->extravalid);
537                                 curbp = state->extrablk.bp;
538                         } else {
539                                 error = xfs_da_read_buf(tp, dp,
540                                                 xfs_dir2_db_to_da(mp, newdb),
541                                                 -1, &curbp, XFS_DATA_FORK);
542                                 if (error)
543                                         return error;
544                         }
545                         xfs_dir2_data_check(dp, curbp);
546                         curdb = newdb;
547                 }
548                 /*
549                  * Point to the data entry.
550                  */
551                 dep = (xfs_dir2_data_entry_t *)((char *)curbp->data +
552                         xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address)));
553                 /*
554                  * Compare the entry and if it's an exact match, return
555                  * EEXIST immediately. If it's the first case-insensitive
556                  * match, store the block & inode number and continue looking.
557                  */
558                 cmp = mp->m_dirnameops->compname(args, dep->name, dep->namelen);
559                 if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) {
560                         /* If there is a CI match block, drop it */
561                         if (args->cmpresult != XFS_CMP_DIFFERENT &&
562                                                 curdb != state->extrablk.blkno)
563                                 xfs_da_brelse(tp, state->extrablk.bp);
564                         args->cmpresult = cmp;
565                         args->inumber = be64_to_cpu(dep->inumber);
566                         *indexp = index;
567                         state->extravalid = 1;
568                         state->extrablk.bp = curbp;
569                         state->extrablk.blkno = curdb;
570                         state->extrablk.index = (int)((char *)dep -
571                                                         (char *)curbp->data);
572                         state->extrablk.magic = XFS_DIR2_DATA_MAGIC;
573                         if (cmp == XFS_CMP_EXACT)
574                                 return XFS_ERROR(EEXIST);
575                 }
576         }
577         ASSERT(index == be16_to_cpu(leaf->hdr.count) ||
578                                         (args->op_flags & XFS_DA_OP_OKNOENT));
579         if (curbp) {
580                 if (args->cmpresult == XFS_CMP_DIFFERENT) {
581                         /* Giving back last used data block. */
582                         state->extravalid = 1;
583                         state->extrablk.bp = curbp;
584                         state->extrablk.index = -1;
585                         state->extrablk.blkno = curdb;
586                         state->extrablk.magic = XFS_DIR2_DATA_MAGIC;
587                 } else {
588                         /* If the curbp is not the CI match block, drop it */
589                         if (state->extrablk.bp != curbp)
590                                 xfs_da_brelse(tp, curbp);
591                 }
592         } else {
593                 state->extravalid = 0;
594         }
595         *indexp = index;
596         return XFS_ERROR(ENOENT);
597 }
598
599 /*
600  * Look up a leaf entry in a node-format leaf block.
601  * If this is an addname then the extrablk in state is a freespace block,
602  * otherwise it's a data block.
603  */
604 int
605 xfs_dir2_leafn_lookup_int(
606         xfs_dabuf_t             *bp,            /* leaf buffer */
607         xfs_da_args_t           *args,          /* operation arguments */
608         int                     *indexp,        /* out: leaf entry index */
609         xfs_da_state_t          *state)         /* state to fill in */
610 {
611         if (args->op_flags & XFS_DA_OP_ADDNAME)
612                 return xfs_dir2_leafn_lookup_for_addname(bp, args, indexp,
613                                                         state);
614         return xfs_dir2_leafn_lookup_for_entry(bp, args, indexp, state);
615 }
616
617 /*
618  * Move count leaf entries from source to destination leaf.
619  * Log entries and headers.  Stale entries are preserved.
620  */
621 static void
622 xfs_dir2_leafn_moveents(
623         xfs_da_args_t   *args,                  /* operation arguments */
624         xfs_dabuf_t     *bp_s,                  /* source leaf buffer */
625         int             start_s,                /* source leaf index */
626         xfs_dabuf_t     *bp_d,                  /* destination leaf buffer */
627         int             start_d,                /* destination leaf index */
628         int             count)                  /* count of leaves to copy */
629 {
630         xfs_dir2_leaf_t *leaf_d;                /* destination leaf structure */
631         xfs_dir2_leaf_t *leaf_s;                /* source leaf structure */
632         int             stale;                  /* count stale leaves copied */
633         xfs_trans_t     *tp;                    /* transaction pointer */
634
635         trace_xfs_dir2_leafn_moveents(args, start_s, start_d, count);
636
637         /*
638          * Silently return if nothing to do.
639          */
640         if (count == 0) {
641                 return;
642         }
643         tp = args->trans;
644         leaf_s = bp_s->data;
645         leaf_d = bp_d->data;
646         /*
647          * If the destination index is not the end of the current
648          * destination leaf entries, open up a hole in the destination
649          * to hold the new entries.
650          */
651         if (start_d < be16_to_cpu(leaf_d->hdr.count)) {
652                 memmove(&leaf_d->ents[start_d + count], &leaf_d->ents[start_d],
653                         (be16_to_cpu(leaf_d->hdr.count) - start_d) *
654                         sizeof(xfs_dir2_leaf_entry_t));
655                 xfs_dir2_leaf_log_ents(tp, bp_d, start_d + count,
656                         count + be16_to_cpu(leaf_d->hdr.count) - 1);
657         }
658         /*
659          * If the source has stale leaves, count the ones in the copy range
660          * so we can update the header correctly.
661          */
662         if (leaf_s->hdr.stale) {
663                 int     i;                      /* temp leaf index */
664
665                 for (i = start_s, stale = 0; i < start_s + count; i++) {
666                         if (leaf_s->ents[i].address ==
667                             cpu_to_be32(XFS_DIR2_NULL_DATAPTR))
668                                 stale++;
669                 }
670         } else
671                 stale = 0;
672         /*
673          * Copy the leaf entries from source to destination.
674          */
675         memcpy(&leaf_d->ents[start_d], &leaf_s->ents[start_s],
676                 count * sizeof(xfs_dir2_leaf_entry_t));
677         xfs_dir2_leaf_log_ents(tp, bp_d, start_d, start_d + count - 1);
678         /*
679          * If there are source entries after the ones we copied,
680          * delete the ones we copied by sliding the next ones down.
681          */
682         if (start_s + count < be16_to_cpu(leaf_s->hdr.count)) {
683                 memmove(&leaf_s->ents[start_s], &leaf_s->ents[start_s + count],
684                         count * sizeof(xfs_dir2_leaf_entry_t));
685                 xfs_dir2_leaf_log_ents(tp, bp_s, start_s, start_s + count - 1);
686         }
687         /*
688          * Update the headers and log them.
689          */
690         be16_add_cpu(&leaf_s->hdr.count, -(count));
691         be16_add_cpu(&leaf_s->hdr.stale, -(stale));
692         be16_add_cpu(&leaf_d->hdr.count, count);
693         be16_add_cpu(&leaf_d->hdr.stale, stale);
694         xfs_dir2_leaf_log_header(tp, bp_s);
695         xfs_dir2_leaf_log_header(tp, bp_d);
696         xfs_dir2_leafn_check(args->dp, bp_s);
697         xfs_dir2_leafn_check(args->dp, bp_d);
698 }
699
700 /*
701  * Determine the sort order of two leaf blocks.
702  * Returns 1 if both are valid and leaf2 should be before leaf1, else 0.
703  */
704 int                                             /* sort order */
705 xfs_dir2_leafn_order(
706         xfs_dabuf_t     *leaf1_bp,              /* leaf1 buffer */
707         xfs_dabuf_t     *leaf2_bp)              /* leaf2 buffer */
708 {
709         xfs_dir2_leaf_t *leaf1;                 /* leaf1 structure */
710         xfs_dir2_leaf_t *leaf2;                 /* leaf2 structure */
711
712         leaf1 = leaf1_bp->data;
713         leaf2 = leaf2_bp->data;
714         ASSERT(leaf1->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
715         ASSERT(leaf2->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
716         if (be16_to_cpu(leaf1->hdr.count) > 0 &&
717             be16_to_cpu(leaf2->hdr.count) > 0 &&
718             (be32_to_cpu(leaf2->ents[0].hashval) < be32_to_cpu(leaf1->ents[0].hashval) ||
719              be32_to_cpu(leaf2->ents[be16_to_cpu(leaf2->hdr.count) - 1].hashval) <
720              be32_to_cpu(leaf1->ents[be16_to_cpu(leaf1->hdr.count) - 1].hashval)))
721                 return 1;
722         return 0;
723 }
724
725 /*
726  * Rebalance leaf entries between two leaf blocks.
727  * This is actually only called when the second block is new,
728  * though the code deals with the general case.
729  * A new entry will be inserted in one of the blocks, and that
730  * entry is taken into account when balancing.
731  */
732 static void
733 xfs_dir2_leafn_rebalance(
734         xfs_da_state_t          *state,         /* btree cursor */
735         xfs_da_state_blk_t      *blk1,          /* first btree block */
736         xfs_da_state_blk_t      *blk2)          /* second btree block */
737 {
738         xfs_da_args_t           *args;          /* operation arguments */
739         int                     count;          /* count (& direction) leaves */
740         int                     isleft;         /* new goes in left leaf */
741         xfs_dir2_leaf_t         *leaf1;         /* first leaf structure */
742         xfs_dir2_leaf_t         *leaf2;         /* second leaf structure */
743         int                     mid;            /* midpoint leaf index */
744 #ifdef DEBUG
745         int                     oldstale;       /* old count of stale leaves */
746 #endif
747         int                     oldsum;         /* old total leaf count */
748         int                     swap;           /* swapped leaf blocks */
749
750         args = state->args;
751         /*
752          * If the block order is wrong, swap the arguments.
753          */
754         if ((swap = xfs_dir2_leafn_order(blk1->bp, blk2->bp))) {
755                 xfs_da_state_blk_t      *tmp;   /* temp for block swap */
756
757                 tmp = blk1;
758                 blk1 = blk2;
759                 blk2 = tmp;
760         }
761         leaf1 = blk1->bp->data;
762         leaf2 = blk2->bp->data;
763         oldsum = be16_to_cpu(leaf1->hdr.count) + be16_to_cpu(leaf2->hdr.count);
764 #ifdef DEBUG
765         oldstale = be16_to_cpu(leaf1->hdr.stale) + be16_to_cpu(leaf2->hdr.stale);
766 #endif
767         mid = oldsum >> 1;
768         /*
769          * If the old leaf count was odd then the new one will be even,
770          * so we need to divide the new count evenly.
771          */
772         if (oldsum & 1) {
773                 xfs_dahash_t    midhash;        /* middle entry hash value */
774
775                 if (mid >= be16_to_cpu(leaf1->hdr.count))
776                         midhash = be32_to_cpu(leaf2->ents[mid - be16_to_cpu(leaf1->hdr.count)].hashval);
777                 else
778                         midhash = be32_to_cpu(leaf1->ents[mid].hashval);
779                 isleft = args->hashval <= midhash;
780         }
781         /*
782          * If the old count is even then the new count is odd, so there's
783          * no preferred side for the new entry.
784          * Pick the left one.
785          */
786         else
787                 isleft = 1;
788         /*
789          * Calculate moved entry count.  Positive means left-to-right,
790          * negative means right-to-left.  Then move the entries.
791          */
792         count = be16_to_cpu(leaf1->hdr.count) - mid + (isleft == 0);
793         if (count > 0)
794                 xfs_dir2_leafn_moveents(args, blk1->bp,
795                         be16_to_cpu(leaf1->hdr.count) - count, blk2->bp, 0, count);
796         else if (count < 0)
797                 xfs_dir2_leafn_moveents(args, blk2->bp, 0, blk1->bp,
798                         be16_to_cpu(leaf1->hdr.count), count);
799         ASSERT(be16_to_cpu(leaf1->hdr.count) + be16_to_cpu(leaf2->hdr.count) == oldsum);
800         ASSERT(be16_to_cpu(leaf1->hdr.stale) + be16_to_cpu(leaf2->hdr.stale) == oldstale);
801         /*
802          * Mark whether we're inserting into the old or new leaf.
803          */
804         if (be16_to_cpu(leaf1->hdr.count) < be16_to_cpu(leaf2->hdr.count))
805                 state->inleaf = swap;
806         else if (be16_to_cpu(leaf1->hdr.count) > be16_to_cpu(leaf2->hdr.count))
807                 state->inleaf = !swap;
808         else
809                 state->inleaf =
810                         swap ^ (blk1->index <= be16_to_cpu(leaf1->hdr.count));
811         /*
812          * Adjust the expected index for insertion.
813          */
814         if (!state->inleaf)
815                 blk2->index = blk1->index - be16_to_cpu(leaf1->hdr.count);
816
817         /*
818          * Finally sanity check just to make sure we are not returning a
819          * negative index
820          */
821         if(blk2->index < 0) {
822                 state->inleaf = 1;
823                 blk2->index = 0;
824                 xfs_alert(args->dp->i_mount,
825         "%s: picked the wrong leaf? reverting original leaf: blk1->index %d\n",
826                         __func__, blk1->index);
827         }
828 }
829
830 /*
831  * Remove an entry from a node directory.
832  * This removes the leaf entry and the data entry,
833  * and updates the free block if necessary.
834  */
835 static int                                      /* error */
836 xfs_dir2_leafn_remove(
837         xfs_da_args_t           *args,          /* operation arguments */
838         xfs_dabuf_t             *bp,            /* leaf buffer */
839         int                     index,          /* leaf entry index */
840         xfs_da_state_blk_t      *dblk,          /* data block */
841         int                     *rval)          /* resulting block needs join */
842 {
843         xfs_dir2_data_hdr_t     *hdr;           /* data block header */
844         xfs_dir2_db_t           db;             /* data block number */
845         xfs_dabuf_t             *dbp;           /* data block buffer */
846         xfs_dir2_data_entry_t   *dep;           /* data block entry */
847         xfs_inode_t             *dp;            /* incore directory inode */
848         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
849         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry */
850         int                     longest;        /* longest data free entry */
851         int                     off;            /* data block entry offset */
852         xfs_mount_t             *mp;            /* filesystem mount point */
853         int                     needlog;        /* need to log data header */
854         int                     needscan;       /* need to rescan data frees */
855         xfs_trans_t             *tp;            /* transaction pointer */
856
857         trace_xfs_dir2_leafn_remove(args, index);
858
859         dp = args->dp;
860         tp = args->trans;
861         mp = dp->i_mount;
862         leaf = bp->data;
863         ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
864         /*
865          * Point to the entry we're removing.
866          */
867         lep = &leaf->ents[index];
868         /*
869          * Extract the data block and offset from the entry.
870          */
871         db = xfs_dir2_dataptr_to_db(mp, be32_to_cpu(lep->address));
872         ASSERT(dblk->blkno == db);
873         off = xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address));
874         ASSERT(dblk->index == off);
875         /*
876          * Kill the leaf entry by marking it stale.
877          * Log the leaf block changes.
878          */
879         be16_add_cpu(&leaf->hdr.stale, 1);
880         xfs_dir2_leaf_log_header(tp, bp);
881         lep->address = cpu_to_be32(XFS_DIR2_NULL_DATAPTR);
882         xfs_dir2_leaf_log_ents(tp, bp, index, index);
883         /*
884          * Make the data entry free.  Keep track of the longest freespace
885          * in the data block in case it changes.
886          */
887         dbp = dblk->bp;
888         hdr = dbp->data;
889         dep = (xfs_dir2_data_entry_t *)((char *)hdr + off);
890         longest = be16_to_cpu(hdr->bestfree[0].length);
891         needlog = needscan = 0;
892         xfs_dir2_data_make_free(tp, dbp, off,
893                 xfs_dir2_data_entsize(dep->namelen), &needlog, &needscan);
894         /*
895          * Rescan the data block freespaces for bestfree.
896          * Log the data block header if needed.
897          */
898         if (needscan)
899                 xfs_dir2_data_freescan(mp, hdr, &needlog);
900         if (needlog)
901                 xfs_dir2_data_log_header(tp, dbp);
902         xfs_dir2_data_check(dp, dbp);
903         /*
904          * If the longest data block freespace changes, need to update
905          * the corresponding freeblock entry.
906          */
907         if (longest < be16_to_cpu(hdr->bestfree[0].length)) {
908                 int             error;          /* error return value */
909                 xfs_dabuf_t     *fbp;           /* freeblock buffer */
910                 xfs_dir2_db_t   fdb;            /* freeblock block number */
911                 int             findex;         /* index in freeblock entries */
912                 xfs_dir2_free_t *free;          /* freeblock structure */
913                 int             logfree;        /* need to log free entry */
914
915                 /*
916                  * Convert the data block number to a free block,
917                  * read in the free block.
918                  */
919                 fdb = xfs_dir2_db_to_fdb(mp, db);
920                 if ((error = xfs_da_read_buf(tp, dp, xfs_dir2_db_to_da(mp, fdb),
921                                 -1, &fbp, XFS_DATA_FORK))) {
922                         return error;
923                 }
924                 free = fbp->data;
925                 ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
926                 ASSERT(be32_to_cpu(free->hdr.firstdb) ==
927                        xfs_dir2_free_max_bests(mp) *
928                        (fdb - XFS_DIR2_FREE_FIRSTDB(mp)));
929                 /*
930                  * Calculate which entry we need to fix.
931                  */
932                 findex = xfs_dir2_db_to_fdindex(mp, db);
933                 longest = be16_to_cpu(hdr->bestfree[0].length);
934                 /*
935                  * If the data block is now empty we can get rid of it
936                  * (usually).
937                  */
938                 if (longest == mp->m_dirblksize - (uint)sizeof(*hdr)) {
939                         /*
940                          * Try to punch out the data block.
941                          */
942                         error = xfs_dir2_shrink_inode(args, db, dbp);
943                         if (error == 0) {
944                                 dblk->bp = NULL;
945                                 hdr = NULL;
946                         }
947                         /*
948                          * We can get ENOSPC if there's no space reservation.
949                          * In this case just drop the buffer and some one else
950                          * will eventually get rid of the empty block.
951                          */
952                         else if (error == ENOSPC && args->total == 0)
953                                 xfs_da_buf_done(dbp);
954                         else
955                                 return error;
956                 }
957                 /*
958                  * If we got rid of the data block, we can eliminate that entry
959                  * in the free block.
960                  */
961                 if (hdr == NULL) {
962                         /*
963                          * One less used entry in the free table.
964                          */
965                         be32_add_cpu(&free->hdr.nused, -1);
966                         xfs_dir2_free_log_header(tp, fbp);
967                         /*
968                          * If this was the last entry in the table, we can
969                          * trim the table size back.  There might be other
970                          * entries at the end referring to non-existent
971                          * data blocks, get those too.
972                          */
973                         if (findex == be32_to_cpu(free->hdr.nvalid) - 1) {
974                                 int     i;              /* free entry index */
975
976                                 for (i = findex - 1;
977                                      i >= 0 &&
978                                      free->bests[i] == cpu_to_be16(NULLDATAOFF);
979                                      i--)
980                                         continue;
981                                 free->hdr.nvalid = cpu_to_be32(i + 1);
982                                 logfree = 0;
983                         }
984                         /*
985                          * Not the last entry, just punch it out.
986                          */
987                         else {
988                                 free->bests[findex] = cpu_to_be16(NULLDATAOFF);
989                                 logfree = 1;
990                         }
991                         /*
992                          * If there are no useful entries left in the block,
993                          * get rid of the block if we can.
994                          */
995                         if (!free->hdr.nused) {
996                                 error = xfs_dir2_shrink_inode(args, fdb, fbp);
997                                 if (error == 0) {
998                                         fbp = NULL;
999                                         logfree = 0;
1000                                 } else if (error != ENOSPC || args->total != 0)
1001                                         return error;
1002                                 /*
1003                                  * It's possible to get ENOSPC if there is no
1004                                  * space reservation.  In this case some one
1005                                  * else will eventually get rid of this block.
1006                                  */
1007                         }
1008                 }
1009                 /*
1010                  * Data block is not empty, just set the free entry to
1011                  * the new value.
1012                  */
1013                 else {
1014                         free->bests[findex] = cpu_to_be16(longest);
1015                         logfree = 1;
1016                 }
1017                 /*
1018                  * Log the free entry that changed, unless we got rid of it.
1019                  */
1020                 if (logfree)
1021                         xfs_dir2_free_log_bests(tp, fbp, findex, findex);
1022                 /*
1023                  * Drop the buffer if we still have it.
1024                  */
1025                 if (fbp)
1026                         xfs_da_buf_done(fbp);
1027         }
1028         xfs_dir2_leafn_check(dp, bp);
1029         /*
1030          * Return indication of whether this leaf block is empty enough
1031          * to justify trying to join it with a neighbor.
1032          */
1033         *rval =
1034                 ((uint)sizeof(leaf->hdr) +
1035                  (uint)sizeof(leaf->ents[0]) *
1036                  (be16_to_cpu(leaf->hdr.count) - be16_to_cpu(leaf->hdr.stale))) <
1037                 mp->m_dir_magicpct;
1038         return 0;
1039 }
1040
1041 /*
1042  * Split the leaf entries in the old block into old and new blocks.
1043  */
1044 int                                             /* error */
1045 xfs_dir2_leafn_split(
1046         xfs_da_state_t          *state,         /* btree cursor */
1047         xfs_da_state_blk_t      *oldblk,        /* original block */
1048         xfs_da_state_blk_t      *newblk)        /* newly created block */
1049 {
1050         xfs_da_args_t           *args;          /* operation arguments */
1051         xfs_dablk_t             blkno;          /* new leaf block number */
1052         int                     error;          /* error return value */
1053         xfs_mount_t             *mp;            /* filesystem mount point */
1054
1055         /*
1056          * Allocate space for a new leaf node.
1057          */
1058         args = state->args;
1059         mp = args->dp->i_mount;
1060         ASSERT(args != NULL);
1061         ASSERT(oldblk->magic == XFS_DIR2_LEAFN_MAGIC);
1062         error = xfs_da_grow_inode(args, &blkno);
1063         if (error) {
1064                 return error;
1065         }
1066         /*
1067          * Initialize the new leaf block.
1068          */
1069         error = xfs_dir2_leaf_init(args, xfs_dir2_da_to_db(mp, blkno),
1070                 &newblk->bp, XFS_DIR2_LEAFN_MAGIC);
1071         if (error) {
1072                 return error;
1073         }
1074         newblk->blkno = blkno;
1075         newblk->magic = XFS_DIR2_LEAFN_MAGIC;
1076         /*
1077          * Rebalance the entries across the two leaves, link the new
1078          * block into the leaves.
1079          */
1080         xfs_dir2_leafn_rebalance(state, oldblk, newblk);
1081         error = xfs_da_blk_link(state, oldblk, newblk);
1082         if (error) {
1083                 return error;
1084         }
1085         /*
1086          * Insert the new entry in the correct block.
1087          */
1088         if (state->inleaf)
1089                 error = xfs_dir2_leafn_add(oldblk->bp, args, oldblk->index);
1090         else
1091                 error = xfs_dir2_leafn_add(newblk->bp, args, newblk->index);
1092         /*
1093          * Update last hashval in each block since we added the name.
1094          */
1095         oldblk->hashval = xfs_dir2_leafn_lasthash(oldblk->bp, NULL);
1096         newblk->hashval = xfs_dir2_leafn_lasthash(newblk->bp, NULL);
1097         xfs_dir2_leafn_check(args->dp, oldblk->bp);
1098         xfs_dir2_leafn_check(args->dp, newblk->bp);
1099         return error;
1100 }
1101
1102 /*
1103  * Check a leaf block and its neighbors to see if the block should be
1104  * collapsed into one or the other neighbor.  Always keep the block
1105  * with the smaller block number.
1106  * If the current block is over 50% full, don't try to join it, return 0.
1107  * If the block is empty, fill in the state structure and return 2.
1108  * If it can be collapsed, fill in the state structure and return 1.
1109  * If nothing can be done, return 0.
1110  */
1111 int                                             /* error */
1112 xfs_dir2_leafn_toosmall(
1113         xfs_da_state_t          *state,         /* btree cursor */
1114         int                     *action)        /* resulting action to take */
1115 {
1116         xfs_da_state_blk_t      *blk;           /* leaf block */
1117         xfs_dablk_t             blkno;          /* leaf block number */
1118         xfs_dabuf_t             *bp;            /* leaf buffer */
1119         int                     bytes;          /* bytes in use */
1120         int                     count;          /* leaf live entry count */
1121         int                     error;          /* error return value */
1122         int                     forward;        /* sibling block direction */
1123         int                     i;              /* sibling counter */
1124         xfs_da_blkinfo_t        *info;          /* leaf block header */
1125         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1126         int                     rval;           /* result from path_shift */
1127
1128         /*
1129          * Check for the degenerate case of the block being over 50% full.
1130          * If so, it's not worth even looking to see if we might be able
1131          * to coalesce with a sibling.
1132          */
1133         blk = &state->path.blk[state->path.active - 1];
1134         info = blk->bp->data;
1135         ASSERT(info->magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
1136         leaf = (xfs_dir2_leaf_t *)info;
1137         count = be16_to_cpu(leaf->hdr.count) - be16_to_cpu(leaf->hdr.stale);
1138         bytes = (uint)sizeof(leaf->hdr) + count * (uint)sizeof(leaf->ents[0]);
1139         if (bytes > (state->blocksize >> 1)) {
1140                 /*
1141                  * Blk over 50%, don't try to join.
1142                  */
1143                 *action = 0;
1144                 return 0;
1145         }
1146         /*
1147          * Check for the degenerate case of the block being empty.
1148          * If the block is empty, we'll simply delete it, no need to
1149          * coalesce it with a sibling block.  We choose (arbitrarily)
1150          * to merge with the forward block unless it is NULL.
1151          */
1152         if (count == 0) {
1153                 /*
1154                  * Make altpath point to the block we want to keep and
1155                  * path point to the block we want to drop (this one).
1156                  */
1157                 forward = (info->forw != 0);
1158                 memcpy(&state->altpath, &state->path, sizeof(state->path));
1159                 error = xfs_da_path_shift(state, &state->altpath, forward, 0,
1160                         &rval);
1161                 if (error)
1162                         return error;
1163                 *action = rval ? 2 : 0;
1164                 return 0;
1165         }
1166         /*
1167          * Examine each sibling block to see if we can coalesce with
1168          * at least 25% free space to spare.  We need to figure out
1169          * whether to merge with the forward or the backward block.
1170          * We prefer coalescing with the lower numbered sibling so as
1171          * to shrink a directory over time.
1172          */
1173         forward = be32_to_cpu(info->forw) < be32_to_cpu(info->back);
1174         for (i = 0, bp = NULL; i < 2; forward = !forward, i++) {
1175                 blkno = forward ? be32_to_cpu(info->forw) : be32_to_cpu(info->back);
1176                 if (blkno == 0)
1177                         continue;
1178                 /*
1179                  * Read the sibling leaf block.
1180                  */
1181                 if ((error =
1182                     xfs_da_read_buf(state->args->trans, state->args->dp, blkno,
1183                             -1, &bp, XFS_DATA_FORK))) {
1184                         return error;
1185                 }
1186                 ASSERT(bp != NULL);
1187                 /*
1188                  * Count bytes in the two blocks combined.
1189                  */
1190                 leaf = (xfs_dir2_leaf_t *)info;
1191                 count = be16_to_cpu(leaf->hdr.count) - be16_to_cpu(leaf->hdr.stale);
1192                 bytes = state->blocksize - (state->blocksize >> 2);
1193                 leaf = bp->data;
1194                 ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
1195                 count += be16_to_cpu(leaf->hdr.count) - be16_to_cpu(leaf->hdr.stale);
1196                 bytes -= count * (uint)sizeof(leaf->ents[0]);
1197                 /*
1198                  * Fits with at least 25% to spare.
1199                  */
1200                 if (bytes >= 0)
1201                         break;
1202                 xfs_da_brelse(state->args->trans, bp);
1203         }
1204         /*
1205          * Didn't like either block, give up.
1206          */
1207         if (i >= 2) {
1208                 *action = 0;
1209                 return 0;
1210         }
1211         /*
1212          * Done with the sibling leaf block here, drop the dabuf
1213          * so path_shift can get it.
1214          */
1215         xfs_da_buf_done(bp);
1216         /*
1217          * Make altpath point to the block we want to keep (the lower
1218          * numbered block) and path point to the block we want to drop.
1219          */
1220         memcpy(&state->altpath, &state->path, sizeof(state->path));
1221         if (blkno < blk->blkno)
1222                 error = xfs_da_path_shift(state, &state->altpath, forward, 0,
1223                         &rval);
1224         else
1225                 error = xfs_da_path_shift(state, &state->path, forward, 0,
1226                         &rval);
1227         if (error) {
1228                 return error;
1229         }
1230         *action = rval ? 0 : 1;
1231         return 0;
1232 }
1233
1234 /*
1235  * Move all the leaf entries from drop_blk to save_blk.
1236  * This is done as part of a join operation.
1237  */
1238 void
1239 xfs_dir2_leafn_unbalance(
1240         xfs_da_state_t          *state,         /* cursor */
1241         xfs_da_state_blk_t      *drop_blk,      /* dead block */
1242         xfs_da_state_blk_t      *save_blk)      /* surviving block */
1243 {
1244         xfs_da_args_t           *args;          /* operation arguments */
1245         xfs_dir2_leaf_t         *drop_leaf;     /* dead leaf structure */
1246         xfs_dir2_leaf_t         *save_leaf;     /* surviving leaf structure */
1247
1248         args = state->args;
1249         ASSERT(drop_blk->magic == XFS_DIR2_LEAFN_MAGIC);
1250         ASSERT(save_blk->magic == XFS_DIR2_LEAFN_MAGIC);
1251         drop_leaf = drop_blk->bp->data;
1252         save_leaf = save_blk->bp->data;
1253         ASSERT(drop_leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
1254         ASSERT(save_leaf->hdr.info.magic == cpu_to_be16(XFS_DIR2_LEAFN_MAGIC));
1255         /*
1256          * If there are any stale leaf entries, take this opportunity
1257          * to purge them.
1258          */
1259         if (drop_leaf->hdr.stale)
1260                 xfs_dir2_leaf_compact(args, drop_blk->bp);
1261         if (save_leaf->hdr.stale)
1262                 xfs_dir2_leaf_compact(args, save_blk->bp);
1263         /*
1264          * Move the entries from drop to the appropriate end of save.
1265          */
1266         drop_blk->hashval = be32_to_cpu(drop_leaf->ents[be16_to_cpu(drop_leaf->hdr.count) - 1].hashval);
1267         if (xfs_dir2_leafn_order(save_blk->bp, drop_blk->bp))
1268                 xfs_dir2_leafn_moveents(args, drop_blk->bp, 0, save_blk->bp, 0,
1269                         be16_to_cpu(drop_leaf->hdr.count));
1270         else
1271                 xfs_dir2_leafn_moveents(args, drop_blk->bp, 0, save_blk->bp,
1272                         be16_to_cpu(save_leaf->hdr.count), be16_to_cpu(drop_leaf->hdr.count));
1273         save_blk->hashval = be32_to_cpu(save_leaf->ents[be16_to_cpu(save_leaf->hdr.count) - 1].hashval);
1274         xfs_dir2_leafn_check(args->dp, save_blk->bp);
1275 }
1276
1277 /*
1278  * Top-level node form directory addname routine.
1279  */
1280 int                                             /* error */
1281 xfs_dir2_node_addname(
1282         xfs_da_args_t           *args)          /* operation arguments */
1283 {
1284         xfs_da_state_blk_t      *blk;           /* leaf block for insert */
1285         int                     error;          /* error return value */
1286         int                     rval;           /* sub-return value */
1287         xfs_da_state_t          *state;         /* btree cursor */
1288
1289         trace_xfs_dir2_node_addname(args);
1290
1291         /*
1292          * Allocate and initialize the state (btree cursor).
1293          */
1294         state = xfs_da_state_alloc();
1295         state->args = args;
1296         state->mp = args->dp->i_mount;
1297         state->blocksize = state->mp->m_dirblksize;
1298         state->node_ents = state->mp->m_dir_node_ents;
1299         /*
1300          * Look up the name.  We're not supposed to find it, but
1301          * this gives us the insertion point.
1302          */
1303         error = xfs_da_node_lookup_int(state, &rval);
1304         if (error)
1305                 rval = error;
1306         if (rval != ENOENT) {
1307                 goto done;
1308         }
1309         /*
1310          * Add the data entry to a data block.
1311          * Extravalid is set to a freeblock found by lookup.
1312          */
1313         rval = xfs_dir2_node_addname_int(args,
1314                 state->extravalid ? &state->extrablk : NULL);
1315         if (rval) {
1316                 goto done;
1317         }
1318         blk = &state->path.blk[state->path.active - 1];
1319         ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
1320         /*
1321          * Add the new leaf entry.
1322          */
1323         rval = xfs_dir2_leafn_add(blk->bp, args, blk->index);
1324         if (rval == 0) {
1325                 /*
1326                  * It worked, fix the hash values up the btree.
1327                  */
1328                 if (!(args->op_flags & XFS_DA_OP_JUSTCHECK))
1329                         xfs_da_fixhashpath(state, &state->path);
1330         } else {
1331                 /*
1332                  * It didn't work, we need to split the leaf block.
1333                  */
1334                 if (args->total == 0) {
1335                         ASSERT(rval == ENOSPC);
1336                         goto done;
1337                 }
1338                 /*
1339                  * Split the leaf block and insert the new entry.
1340                  */
1341                 rval = xfs_da_split(state);
1342         }
1343 done:
1344         xfs_da_state_free(state);
1345         return rval;
1346 }
1347
1348 /*
1349  * Add the data entry for a node-format directory name addition.
1350  * The leaf entry is added in xfs_dir2_leafn_add.
1351  * We may enter with a freespace block that the lookup found.
1352  */
1353 static int                                      /* error */
1354 xfs_dir2_node_addname_int(
1355         xfs_da_args_t           *args,          /* operation arguments */
1356         xfs_da_state_blk_t      *fblk)          /* optional freespace block */
1357 {
1358         xfs_dir2_data_hdr_t     *hdr;           /* data block header */
1359         xfs_dir2_db_t           dbno;           /* data block number */
1360         xfs_dabuf_t             *dbp;           /* data block buffer */
1361         xfs_dir2_data_entry_t   *dep;           /* data entry pointer */
1362         xfs_inode_t             *dp;            /* incore directory inode */
1363         xfs_dir2_data_unused_t  *dup;           /* data unused entry pointer */
1364         int                     error;          /* error return value */
1365         xfs_dir2_db_t           fbno;           /* freespace block number */
1366         xfs_dabuf_t             *fbp;           /* freespace buffer */
1367         int                     findex;         /* freespace entry index */
1368         xfs_dir2_free_t         *free=NULL;     /* freespace block structure */
1369         xfs_dir2_db_t           ifbno;          /* initial freespace block no */
1370         xfs_dir2_db_t           lastfbno=0;     /* highest freespace block no */
1371         int                     length;         /* length of the new entry */
1372         int                     logfree;        /* need to log free entry */
1373         xfs_mount_t             *mp;            /* filesystem mount point */
1374         int                     needlog;        /* need to log data header */
1375         int                     needscan;       /* need to rescan data frees */
1376         __be16                  *tagp;          /* data entry tag pointer */
1377         xfs_trans_t             *tp;            /* transaction pointer */
1378
1379         dp = args->dp;
1380         mp = dp->i_mount;
1381         tp = args->trans;
1382         length = xfs_dir2_data_entsize(args->namelen);
1383         /*
1384          * If we came in with a freespace block that means that lookup
1385          * found an entry with our hash value.  This is the freespace
1386          * block for that data entry.
1387          */
1388         if (fblk) {
1389                 fbp = fblk->bp;
1390                 /*
1391                  * Remember initial freespace block number.
1392                  */
1393                 ifbno = fblk->blkno;
1394                 free = fbp->data;
1395                 ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
1396                 findex = fblk->index;
1397                 /*
1398                  * This means the free entry showed that the data block had
1399                  * space for our entry, so we remembered it.
1400                  * Use that data block.
1401                  */
1402                 if (findex >= 0) {
1403                         ASSERT(findex < be32_to_cpu(free->hdr.nvalid));
1404                         ASSERT(be16_to_cpu(free->bests[findex]) != NULLDATAOFF);
1405                         ASSERT(be16_to_cpu(free->bests[findex]) >= length);
1406                         dbno = be32_to_cpu(free->hdr.firstdb) + findex;
1407                 }
1408                 /*
1409                  * The data block looked at didn't have enough room.
1410                  * We'll start at the beginning of the freespace entries.
1411                  */
1412                 else {
1413                         dbno = -1;
1414                         findex = 0;
1415                 }
1416         }
1417         /*
1418          * Didn't come in with a freespace block, so don't have a data block.
1419          */
1420         else {
1421                 ifbno = dbno = -1;
1422                 fbp = NULL;
1423                 findex = 0;
1424         }
1425         /*
1426          * If we don't have a data block yet, we're going to scan the
1427          * freespace blocks looking for one.  Figure out what the
1428          * highest freespace block number is.
1429          */
1430         if (dbno == -1) {
1431                 xfs_fileoff_t   fo;             /* freespace block number */
1432
1433                 if ((error = xfs_bmap_last_offset(tp, dp, &fo, XFS_DATA_FORK)))
1434                         return error;
1435                 lastfbno = xfs_dir2_da_to_db(mp, (xfs_dablk_t)fo);
1436                 fbno = ifbno;
1437         }
1438         /*
1439          * While we haven't identified a data block, search the freeblock
1440          * data for a good data block.  If we find a null freeblock entry,
1441          * indicating a hole in the data blocks, remember that.
1442          */
1443         while (dbno == -1) {
1444                 /*
1445                  * If we don't have a freeblock in hand, get the next one.
1446                  */
1447                 if (fbp == NULL) {
1448                         /*
1449                          * Happens the first time through unless lookup gave
1450                          * us a freespace block to start with.
1451                          */
1452                         if (++fbno == 0)
1453                                 fbno = XFS_DIR2_FREE_FIRSTDB(mp);
1454                         /*
1455                          * If it's ifbno we already looked at it.
1456                          */
1457                         if (fbno == ifbno)
1458                                 fbno++;
1459                         /*
1460                          * If it's off the end we're done.
1461                          */
1462                         if (fbno >= lastfbno)
1463                                 break;
1464                         /*
1465                          * Read the block.  There can be holes in the
1466                          * freespace blocks, so this might not succeed.
1467                          * This should be really rare, so there's no reason
1468                          * to avoid it.
1469                          */
1470                         if ((error = xfs_da_read_buf(tp, dp,
1471                                         xfs_dir2_db_to_da(mp, fbno), -2, &fbp,
1472                                         XFS_DATA_FORK))) {
1473                                 return error;
1474                         }
1475                         if (unlikely(fbp == NULL)) {
1476                                 continue;
1477                         }
1478                         free = fbp->data;
1479                         ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
1480                         findex = 0;
1481                 }
1482                 /*
1483                  * Look at the current free entry.  Is it good enough?
1484                  */
1485                 if (be16_to_cpu(free->bests[findex]) != NULLDATAOFF &&
1486                     be16_to_cpu(free->bests[findex]) >= length)
1487                         dbno = be32_to_cpu(free->hdr.firstdb) + findex;
1488                 else {
1489                         /*
1490                          * Are we done with the freeblock?
1491                          */
1492                         if (++findex == be32_to_cpu(free->hdr.nvalid)) {
1493                                 /*
1494                                  * Drop the block.
1495                                  */
1496                                 xfs_da_brelse(tp, fbp);
1497                                 fbp = NULL;
1498                                 if (fblk && fblk->bp)
1499                                         fblk->bp = NULL;
1500                         }
1501                 }
1502         }
1503         /*
1504          * If we don't have a data block, we need to allocate one and make
1505          * the freespace entries refer to it.
1506          */
1507         if (unlikely(dbno == -1)) {
1508                 /*
1509                  * Not allowed to allocate, return failure.
1510                  */
1511                 if ((args->op_flags & XFS_DA_OP_JUSTCHECK) ||
1512                                                         args->total == 0) {
1513                         /*
1514                          * Drop the freespace buffer unless it came from our
1515                          * caller.
1516                          */
1517                         if ((fblk == NULL || fblk->bp == NULL) && fbp != NULL)
1518                                 xfs_da_buf_done(fbp);
1519                         return XFS_ERROR(ENOSPC);
1520                 }
1521                 /*
1522                  * Allocate and initialize the new data block.
1523                  */
1524                 if (unlikely((error = xfs_dir2_grow_inode(args,
1525                                                          XFS_DIR2_DATA_SPACE,
1526                                                          &dbno)) ||
1527                     (error = xfs_dir2_data_init(args, dbno, &dbp)))) {
1528                         /*
1529                          * Drop the freespace buffer unless it came from our
1530                          * caller.
1531                          */
1532                         if ((fblk == NULL || fblk->bp == NULL) && fbp != NULL)
1533                                 xfs_da_buf_done(fbp);
1534                         return error;
1535                 }
1536                 /*
1537                  * If (somehow) we have a freespace block, get rid of it.
1538                  */
1539                 if (fbp)
1540                         xfs_da_brelse(tp, fbp);
1541                 if (fblk && fblk->bp)
1542                         fblk->bp = NULL;
1543
1544                 /*
1545                  * Get the freespace block corresponding to the data block
1546                  * that was just allocated.
1547                  */
1548                 fbno = xfs_dir2_db_to_fdb(mp, dbno);
1549                 if (unlikely(error = xfs_da_read_buf(tp, dp,
1550                                 xfs_dir2_db_to_da(mp, fbno), -2, &fbp,
1551                                 XFS_DATA_FORK))) {
1552                         xfs_da_buf_done(dbp);
1553                         return error;
1554                 }
1555                 /*
1556                  * If there wasn't a freespace block, the read will
1557                  * return a NULL fbp.  Allocate and initialize a new one.
1558                  */
1559                 if( fbp == NULL ) {
1560                         if ((error = xfs_dir2_grow_inode(args, XFS_DIR2_FREE_SPACE,
1561                                                         &fbno))) {
1562                                 return error;
1563                         }
1564
1565                         if (unlikely(xfs_dir2_db_to_fdb(mp, dbno) != fbno)) {
1566                                 xfs_alert(mp,
1567                         "%s: dir ino " "%llu needed freesp block %lld for\n"
1568                         "  data block %lld, got %lld ifbno %llu lastfbno %d",
1569                                         __func__, (unsigned long long)dp->i_ino,
1570                                         (long long)xfs_dir2_db_to_fdb(mp, dbno),
1571                                         (long long)dbno, (long long)fbno,
1572                                         (unsigned long long)ifbno, lastfbno);
1573                                 if (fblk) {
1574                                         xfs_alert(mp,
1575                                 " fblk 0x%p blkno %llu index %d magic 0x%x",
1576                                                 fblk,
1577                                                 (unsigned long long)fblk->blkno,
1578                                                 fblk->index,
1579                                                 fblk->magic);
1580                                 } else {
1581                                         xfs_alert(mp, " ... fblk is NULL");
1582                                 }
1583                                 XFS_ERROR_REPORT("xfs_dir2_node_addname_int",
1584                                                  XFS_ERRLEVEL_LOW, mp);
1585                                 return XFS_ERROR(EFSCORRUPTED);
1586                         }
1587
1588                         /*
1589                          * Get a buffer for the new block.
1590                          */
1591                         if ((error = xfs_da_get_buf(tp, dp,
1592                                                    xfs_dir2_db_to_da(mp, fbno),
1593                                                    -1, &fbp, XFS_DATA_FORK))) {
1594                                 return error;
1595                         }
1596                         ASSERT(fbp != NULL);
1597
1598                         /*
1599                          * Initialize the new block to be empty, and remember
1600                          * its first slot as our empty slot.
1601                          */
1602                         free = fbp->data;
1603                         free->hdr.magic = cpu_to_be32(XFS_DIR2_FREE_MAGIC);
1604                         free->hdr.firstdb = cpu_to_be32(
1605                                 (fbno - XFS_DIR2_FREE_FIRSTDB(mp)) *
1606                                 xfs_dir2_free_max_bests(mp));
1607                         free->hdr.nvalid = 0;
1608                         free->hdr.nused = 0;
1609                 } else {
1610                         free = fbp->data;
1611                         ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
1612                 }
1613
1614                 /*
1615                  * Set the freespace block index from the data block number.
1616                  */
1617                 findex = xfs_dir2_db_to_fdindex(mp, dbno);
1618                 /*
1619                  * If it's after the end of the current entries in the
1620                  * freespace block, extend that table.
1621                  */
1622                 if (findex >= be32_to_cpu(free->hdr.nvalid)) {
1623                         ASSERT(findex < xfs_dir2_free_max_bests(mp));
1624                         free->hdr.nvalid = cpu_to_be32(findex + 1);
1625                         /*
1626                          * Tag new entry so nused will go up.
1627                          */
1628                         free->bests[findex] = cpu_to_be16(NULLDATAOFF);
1629                 }
1630                 /*
1631                  * If this entry was for an empty data block
1632                  * (this should always be true) then update the header.
1633                  */
1634                 if (free->bests[findex] == cpu_to_be16(NULLDATAOFF)) {
1635                         be32_add_cpu(&free->hdr.nused, 1);
1636                         xfs_dir2_free_log_header(tp, fbp);
1637                 }
1638                 /*
1639                  * Update the real value in the table.
1640                  * We haven't allocated the data entry yet so this will
1641                  * change again.
1642                  */
1643                 hdr = dbp->data;
1644                 free->bests[findex] = hdr->bestfree[0].length;
1645                 logfree = 1;
1646         }
1647         /*
1648          * We had a data block so we don't have to make a new one.
1649          */
1650         else {
1651                 /*
1652                  * If just checking, we succeeded.
1653                  */
1654                 if (args->op_flags & XFS_DA_OP_JUSTCHECK) {
1655                         if ((fblk == NULL || fblk->bp == NULL) && fbp != NULL)
1656                                 xfs_da_buf_done(fbp);
1657                         return 0;
1658                 }
1659                 /*
1660                  * Read the data block in.
1661                  */
1662                 if (unlikely(
1663                     error = xfs_da_read_buf(tp, dp, xfs_dir2_db_to_da(mp, dbno),
1664                                 -1, &dbp, XFS_DATA_FORK))) {
1665                         if ((fblk == NULL || fblk->bp == NULL) && fbp != NULL)
1666                                 xfs_da_buf_done(fbp);
1667                         return error;
1668                 }
1669                 hdr = dbp->data;
1670                 logfree = 0;
1671         }
1672         ASSERT(be16_to_cpu(hdr->bestfree[0].length) >= length);
1673         /*
1674          * Point to the existing unused space.
1675          */
1676         dup = (xfs_dir2_data_unused_t *)
1677               ((char *)hdr + be16_to_cpu(hdr->bestfree[0].offset));
1678         needscan = needlog = 0;
1679         /*
1680          * Mark the first part of the unused space, inuse for us.
1681          */
1682         xfs_dir2_data_use_free(tp, dbp, dup,
1683                 (xfs_dir2_data_aoff_t)((char *)dup - (char *)hdr), length,
1684                 &needlog, &needscan);
1685         /*
1686          * Fill in the new entry and log it.
1687          */
1688         dep = (xfs_dir2_data_entry_t *)dup;
1689         dep->inumber = cpu_to_be64(args->inumber);
1690         dep->namelen = args->namelen;
1691         memcpy(dep->name, args->name, dep->namelen);
1692         tagp = xfs_dir2_data_entry_tag_p(dep);
1693         *tagp = cpu_to_be16((char *)dep - (char *)hdr);
1694         xfs_dir2_data_log_entry(tp, dbp, dep);
1695         /*
1696          * Rescan the block for bestfree if needed.
1697          */
1698         if (needscan)
1699                 xfs_dir2_data_freescan(mp, hdr, &needlog);
1700         /*
1701          * Log the data block header if needed.
1702          */
1703         if (needlog)
1704                 xfs_dir2_data_log_header(tp, dbp);
1705         /*
1706          * If the freespace entry is now wrong, update it.
1707          */
1708         if (be16_to_cpu(free->bests[findex]) != be16_to_cpu(hdr->bestfree[0].length)) {
1709                 free->bests[findex] = hdr->bestfree[0].length;
1710                 logfree = 1;
1711         }
1712         /*
1713          * Log the freespace entry if needed.
1714          */
1715         if (logfree)
1716                 xfs_dir2_free_log_bests(tp, fbp, findex, findex);
1717         /*
1718          * If the caller didn't hand us the freespace block, drop it.
1719          */
1720         if ((fblk == NULL || fblk->bp == NULL) && fbp != NULL)
1721                 xfs_da_buf_done(fbp);
1722         /*
1723          * Return the data block and offset in args, then drop the data block.
1724          */
1725         args->blkno = (xfs_dablk_t)dbno;
1726         args->index = be16_to_cpu(*tagp);
1727         xfs_da_buf_done(dbp);
1728         return 0;
1729 }
1730
1731 /*
1732  * Lookup an entry in a node-format directory.
1733  * All the real work happens in xfs_da_node_lookup_int.
1734  * The only real output is the inode number of the entry.
1735  */
1736 int                                             /* error */
1737 xfs_dir2_node_lookup(
1738         xfs_da_args_t   *args)                  /* operation arguments */
1739 {
1740         int             error;                  /* error return value */
1741         int             i;                      /* btree level */
1742         int             rval;                   /* operation return value */
1743         xfs_da_state_t  *state;                 /* btree cursor */
1744
1745         trace_xfs_dir2_node_lookup(args);
1746
1747         /*
1748          * Allocate and initialize the btree cursor.
1749          */
1750         state = xfs_da_state_alloc();
1751         state->args = args;
1752         state->mp = args->dp->i_mount;
1753         state->blocksize = state->mp->m_dirblksize;
1754         state->node_ents = state->mp->m_dir_node_ents;
1755         /*
1756          * Fill in the path to the entry in the cursor.
1757          */
1758         error = xfs_da_node_lookup_int(state, &rval);
1759         if (error)
1760                 rval = error;
1761         else if (rval == ENOENT && args->cmpresult == XFS_CMP_CASE) {
1762                 /* If a CI match, dup the actual name and return EEXIST */
1763                 xfs_dir2_data_entry_t   *dep;
1764
1765                 dep = (xfs_dir2_data_entry_t *)((char *)state->extrablk.bp->
1766                                                 data + state->extrablk.index);
1767                 rval = xfs_dir_cilookup_result(args, dep->name, dep->namelen);
1768         }
1769         /*
1770          * Release the btree blocks and leaf block.
1771          */
1772         for (i = 0; i < state->path.active; i++) {
1773                 xfs_da_brelse(args->trans, state->path.blk[i].bp);
1774                 state->path.blk[i].bp = NULL;
1775         }
1776         /*
1777          * Release the data block if we have it.
1778          */
1779         if (state->extravalid && state->extrablk.bp) {
1780                 xfs_da_brelse(args->trans, state->extrablk.bp);
1781                 state->extrablk.bp = NULL;
1782         }
1783         xfs_da_state_free(state);
1784         return rval;
1785 }
1786
1787 /*
1788  * Remove an entry from a node-format directory.
1789  */
1790 int                                             /* error */
1791 xfs_dir2_node_removename(
1792         xfs_da_args_t           *args)          /* operation arguments */
1793 {
1794         xfs_da_state_blk_t      *blk;           /* leaf block */
1795         int                     error;          /* error return value */
1796         int                     rval;           /* operation return value */
1797         xfs_da_state_t          *state;         /* btree cursor */
1798
1799         trace_xfs_dir2_node_removename(args);
1800
1801         /*
1802          * Allocate and initialize the btree cursor.
1803          */
1804         state = xfs_da_state_alloc();
1805         state->args = args;
1806         state->mp = args->dp->i_mount;
1807         state->blocksize = state->mp->m_dirblksize;
1808         state->node_ents = state->mp->m_dir_node_ents;
1809         /*
1810          * Look up the entry we're deleting, set up the cursor.
1811          */
1812         error = xfs_da_node_lookup_int(state, &rval);
1813         if (error)
1814                 rval = error;
1815         /*
1816          * Didn't find it, upper layer screwed up.
1817          */
1818         if (rval != EEXIST) {
1819                 xfs_da_state_free(state);
1820                 return rval;
1821         }
1822         blk = &state->path.blk[state->path.active - 1];
1823         ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
1824         ASSERT(state->extravalid);
1825         /*
1826          * Remove the leaf and data entries.
1827          * Extrablk refers to the data block.
1828          */
1829         error = xfs_dir2_leafn_remove(args, blk->bp, blk->index,
1830                 &state->extrablk, &rval);
1831         if (error)
1832                 return error;
1833         /*
1834          * Fix the hash values up the btree.
1835          */
1836         xfs_da_fixhashpath(state, &state->path);
1837         /*
1838          * If we need to join leaf blocks, do it.
1839          */
1840         if (rval && state->path.active > 1)
1841                 error = xfs_da_join(state);
1842         /*
1843          * If no errors so far, try conversion to leaf format.
1844          */
1845         if (!error)
1846                 error = xfs_dir2_node_to_leaf(state);
1847         xfs_da_state_free(state);
1848         return error;
1849 }
1850
1851 /*
1852  * Replace an entry's inode number in a node-format directory.
1853  */
1854 int                                             /* error */
1855 xfs_dir2_node_replace(
1856         xfs_da_args_t           *args)          /* operation arguments */
1857 {
1858         xfs_da_state_blk_t      *blk;           /* leaf block */
1859         xfs_dir2_data_hdr_t     *hdr;           /* data block header */
1860         xfs_dir2_data_entry_t   *dep;           /* data entry changed */
1861         int                     error;          /* error return value */
1862         int                     i;              /* btree level */
1863         xfs_ino_t               inum;           /* new inode number */
1864         xfs_dir2_leaf_t         *leaf;          /* leaf structure */
1865         xfs_dir2_leaf_entry_t   *lep;           /* leaf entry being changed */
1866         int                     rval;           /* internal return value */
1867         xfs_da_state_t          *state;         /* btree cursor */
1868
1869         trace_xfs_dir2_node_replace(args);
1870
1871         /*
1872          * Allocate and initialize the btree cursor.
1873          */
1874         state = xfs_da_state_alloc();
1875         state->args = args;
1876         state->mp = args->dp->i_mount;
1877         state->blocksize = state->mp->m_dirblksize;
1878         state->node_ents = state->mp->m_dir_node_ents;
1879         inum = args->inumber;
1880         /*
1881          * Lookup the entry to change in the btree.
1882          */
1883         error = xfs_da_node_lookup_int(state, &rval);
1884         if (error) {
1885                 rval = error;
1886         }
1887         /*
1888          * It should be found, since the vnodeops layer has looked it up
1889          * and locked it.  But paranoia is good.
1890          */
1891         if (rval == EEXIST) {
1892                 /*
1893                  * Find the leaf entry.
1894                  */
1895                 blk = &state->path.blk[state->path.active - 1];
1896                 ASSERT(blk->magic == XFS_DIR2_LEAFN_MAGIC);
1897                 leaf = blk->bp->data;
1898                 lep = &leaf->ents[blk->index];
1899                 ASSERT(state->extravalid);
1900                 /*
1901                  * Point to the data entry.
1902                  */
1903                 hdr = state->extrablk.bp->data;
1904                 ASSERT(hdr->magic == cpu_to_be32(XFS_DIR2_DATA_MAGIC));
1905                 dep = (xfs_dir2_data_entry_t *)
1906                       ((char *)hdr +
1907                        xfs_dir2_dataptr_to_off(state->mp, be32_to_cpu(lep->address)));
1908                 ASSERT(inum != be64_to_cpu(dep->inumber));
1909                 /*
1910                  * Fill in the new inode number and log the entry.
1911                  */
1912                 dep->inumber = cpu_to_be64(inum);
1913                 xfs_dir2_data_log_entry(args->trans, state->extrablk.bp, dep);
1914                 rval = 0;
1915         }
1916         /*
1917          * Didn't find it, and we're holding a data block.  Drop it.
1918          */
1919         else if (state->extravalid) {
1920                 xfs_da_brelse(args->trans, state->extrablk.bp);
1921                 state->extrablk.bp = NULL;
1922         }
1923         /*
1924          * Release all the buffers in the cursor.
1925          */
1926         for (i = 0; i < state->path.active; i++) {
1927                 xfs_da_brelse(args->trans, state->path.blk[i].bp);
1928                 state->path.blk[i].bp = NULL;
1929         }
1930         xfs_da_state_free(state);
1931         return rval;
1932 }
1933
1934 /*
1935  * Trim off a trailing empty freespace block.
1936  * Return (in rvalp) 1 if we did it, 0 if not.
1937  */
1938 int                                             /* error */
1939 xfs_dir2_node_trim_free(
1940         xfs_da_args_t           *args,          /* operation arguments */
1941         xfs_fileoff_t           fo,             /* free block number */
1942         int                     *rvalp)         /* out: did something */
1943 {
1944         xfs_dabuf_t             *bp;            /* freespace buffer */
1945         xfs_inode_t             *dp;            /* incore directory inode */
1946         int                     error;          /* error return code */
1947         xfs_dir2_free_t         *free;          /* freespace structure */
1948         xfs_mount_t             *mp;            /* filesystem mount point */
1949         xfs_trans_t             *tp;            /* transaction pointer */
1950
1951         dp = args->dp;
1952         mp = dp->i_mount;
1953         tp = args->trans;
1954         /*
1955          * Read the freespace block.
1956          */
1957         if (unlikely(error = xfs_da_read_buf(tp, dp, (xfs_dablk_t)fo, -2, &bp,
1958                         XFS_DATA_FORK))) {
1959                 return error;
1960         }
1961
1962         /*
1963          * There can be holes in freespace.  If fo is a hole, there's
1964          * nothing to do.
1965          */
1966         if (bp == NULL) {
1967                 return 0;
1968         }
1969         free = bp->data;
1970         ASSERT(free->hdr.magic == cpu_to_be32(XFS_DIR2_FREE_MAGIC));
1971         /*
1972          * If there are used entries, there's nothing to do.
1973          */
1974         if (be32_to_cpu(free->hdr.nused) > 0) {
1975                 xfs_da_brelse(tp, bp);
1976                 *rvalp = 0;
1977                 return 0;
1978         }
1979         /*
1980          * Blow the block away.
1981          */
1982         if ((error =
1983             xfs_dir2_shrink_inode(args, xfs_dir2_da_to_db(mp, (xfs_dablk_t)fo),
1984                     bp))) {
1985                 /*
1986                  * Can't fail with ENOSPC since that only happens with no
1987                  * space reservation, when breaking up an extent into two
1988                  * pieces.  This is the last block of an extent.
1989                  */
1990                 ASSERT(error != ENOSPC);
1991                 xfs_da_brelse(tp, bp);
1992                 return error;
1993         }
1994         /*
1995          * Return that we succeeded.
1996          */
1997         *rvalp = 1;
1998         return 0;
1999 }