?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
new buffering logic part 1
[cor_2_6_31.git] / fs / xfs / xfs_dir2.c
blobc657bec6d9513849f2ad86dca172e88417742f14
1 /*
2 * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18 #include "xfs.h"
19 #include "xfs_fs.h"
20 #include "xfs_types.h"
21 #include "xfs_bit.h"
22 #include "xfs_log.h"
23 #include "xfs_inum.h"
24 #include "xfs_trans.h"
25 #include "xfs_sb.h"
26 #include "xfs_ag.h"
27 #include "xfs_dir2.h"
28 #include "xfs_dmapi.h"
29 #include "xfs_mount.h"
30 #include "xfs_da_btree.h"
31 #include "xfs_bmap_btree.h"
32 #include "xfs_alloc_btree.h"
33 #include "xfs_dir2_sf.h"
34 #include "xfs_attr_sf.h"
35 #include "xfs_dinode.h"
36 #include "xfs_inode.h"
37 #include "xfs_inode_item.h"
38 #include "xfs_bmap.h"
39 #include "xfs_dir2_data.h"
40 #include "xfs_dir2_leaf.h"
41 #include "xfs_dir2_block.h"
42 #include "xfs_dir2_node.h"
43 #include "xfs_dir2_trace.h"
44 #include "xfs_error.h"
45 #include "xfs_vnodeops.h"
46
47 struct xfs_name xfs_name_dotdot = {"..", 2};
48
49 /*
50 * ASCII case-insensitive (ie. A-Z) support for directories that was
51 * used in IRIX.
52 */
53 STATIC xfs_dahash_t
54 xfs_ascii_ci_hashname(
55 struct xfs_name *name)
56 {
57 xfs_dahash_t hash;
58 int i;
59
60 for (i = 0, hash = 0; i < name->len; i++)
61 hash = tolower(name->name[i]) ^ rol32(hash, 7);
62
63 return hash;
64 }
65
66 STATIC enum xfs_dacmp
67 xfs_ascii_ci_compname(
68 struct xfs_da_args *args,
69 const char *name,
70 int len)
71 {
72 enum xfs_dacmp result;
73 int i;
74
75 if (args->namelen != len)
76 return XFS_CMP_DIFFERENT;
77
78 result = XFS_CMP_EXACT;
79 for (i = 0; i < len; i++) {
80 if (args->name[i] == name[i])
81 continue;
82 if (tolower(args->name[i]) != tolower(name[i]))
83 return XFS_CMP_DIFFERENT;
84 result = XFS_CMP_CASE;
85 }
86
87 return result;
88 }
89
90 static struct xfs_nameops xfs_ascii_ci_nameops = {
91 .hashname = xfs_ascii_ci_hashname,
92 .compname = xfs_ascii_ci_compname,
93 };
94
95 void
96 xfs_dir_mount(
97 xfs_mount_t *mp)
98 {
99 ASSERT(xfs_sb_version_hasdirv2(&mp->m_sb));
100 ASSERT((1 << (mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog)) <=
101 XFS_MAX_BLOCKSIZE);
102 mp->m_dirblksize = 1 << (mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog);
103 mp->m_dirblkfsbs = 1 << mp->m_sb.sb_dirblklog;
104 mp->m_dirdatablk = xfs_dir2_db_to_da(mp, XFS_DIR2_DATA_FIRSTDB(mp));
105 mp->m_dirleafblk = xfs_dir2_db_to_da(mp, XFS_DIR2_LEAF_FIRSTDB(mp));
106 mp->m_dirfreeblk = xfs_dir2_db_to_da(mp, XFS_DIR2_FREE_FIRSTDB(mp));
107 mp->m_attr_node_ents =
108 (mp->m_sb.sb_blocksize - (uint)sizeof(xfs_da_node_hdr_t)) /
109 (uint)sizeof(xfs_da_node_entry_t);
110 mp->m_dir_node_ents =
111 (mp->m_dirblksize - (uint)sizeof(xfs_da_node_hdr_t)) /
112 (uint)sizeof(xfs_da_node_entry_t);
113 mp->m_dir_magicpct = (mp->m_dirblksize * 37) / 100;
114 if (xfs_sb_version_hasasciici(&mp->m_sb))
115 mp->m_dirnameops = &xfs_ascii_ci_nameops;
116 else
117 mp->m_dirnameops = &xfs_default_nameops;
118 }
119
120 /*
121 * Return 1 if directory contains only "." and "..".
122 */
123 int
124 xfs_dir_isempty(
125 xfs_inode_t *dp)
126 {
127 xfs_dir2_sf_t *sfp;
128
129 ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
130 if (dp->i_d.di_size == 0) /* might happen during shutdown. */
131 return 1;
132 if (dp->i_d.di_size > XFS_IFORK_DSIZE(dp))
133 return 0;
134 sfp = (xfs_dir2_sf_t *)dp->i_df.if_u1.if_data;
135 return !sfp->hdr.count;
136 }
137
138 /*
139 * Validate a given inode number.
140 */
141 int
142 xfs_dir_ino_validate(
143 xfs_mount_t *mp,
144 xfs_ino_t ino)
145 {
146 xfs_agblock_t agblkno;
147 xfs_agino_t agino;
148 xfs_agnumber_t agno;
149 int ino_ok;
150 int ioff;
151
152 agno = XFS_INO_TO_AGNO(mp, ino);
153 agblkno = XFS_INO_TO_AGBNO(mp, ino);
154 ioff = XFS_INO_TO_OFFSET(mp, ino);
155 agino = XFS_OFFBNO_TO_AGINO(mp, agblkno, ioff);
156 ino_ok =
157 agno < mp->m_sb.sb_agcount &&
158 agblkno < mp->m_sb.sb_agblocks &&
159 agblkno != 0 &&
160 ioff < (1 << mp->m_sb.sb_inopblog) &&
161 XFS_AGINO_TO_INO(mp, agno, agino) == ino;
162 if (unlikely(XFS_TEST_ERROR(!ino_ok, mp, XFS_ERRTAG_DIR_INO_VALIDATE,
163 XFS_RANDOM_DIR_INO_VALIDATE))) {
164 xfs_fs_cmn_err(CE_WARN, mp, "Invalid inode number 0x%Lx",
165 (unsigned long long) ino);
166 XFS_ERROR_REPORT("xfs_dir_ino_validate", XFS_ERRLEVEL_LOW, mp);
167 return XFS_ERROR(EFSCORRUPTED);
168 }
169 return 0;
170 }
171
172 /*
173 * Initialize a directory with its "." and ".." entries.
174 */
175 int
176 xfs_dir_init(
177 xfs_trans_t *tp,
178 xfs_inode_t *dp,
179 xfs_inode_t *pdp)
180 {
181 xfs_da_args_t args;
182 int error;
183
184 memset((char *)&args, 0, sizeof(args));
185 args.dp = dp;
186 args.trans = tp;
187 ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
188 if ((error = xfs_dir_ino_validate(tp->t_mountp, pdp->i_ino)))
189 return error;
190 return xfs_dir2_sf_create(&args, pdp->i_ino);
191 }
192
193 /*
194 Enter a name in a directory.
195 */
196 int
197 xfs_dir_createname(
198 xfs_trans_t *tp,
199 xfs_inode_t *dp,
200 struct xfs_name *name,
201 xfs_ino_t inum, /* new entry inode number */
202 xfs_fsblock_t *first, /* bmap's firstblock */
203 xfs_bmap_free_t *flist, /* bmap's freeblock list */
204 xfs_extlen_t total) /* bmap's total block count */
205 {
206 xfs_da_args_t args;
207 int rval;
208 int v; /* type-checking value */
209
210 ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
211 if ((rval = xfs_dir_ino_validate(tp->t_mountp, inum)))
212 return rval;
213 XFS_STATS_INC(xs_dir_create);
214
215 memset(&args, 0, sizeof(xfs_da_args_t));
216 args.name = name->name;
217 args.namelen = name->len;
218 args.hashval = dp->i_mount->m_dirnameops->hashname(name);
219 args.inumber = inum;
220 args.dp = dp;
221 args.firstblock = first;
222 args.flist = flist;
223 args.total = total;
224 args.whichfork = XFS_DATA_FORK;
225 args.trans = tp;
226 args.op_flags = XFS_DA_OP_ADDNAME | XFS_DA_OP_OKNOENT;
227
228 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
229 rval = xfs_dir2_sf_addname(&args);
230 else if ((rval = xfs_dir2_isblock(tp, dp, &v)))
231 return rval;
232 else if (v)
233 rval = xfs_dir2_block_addname(&args);
234 else if ((rval = xfs_dir2_isleaf(tp, dp, &v)))
235 return rval;
236 else if (v)
237 rval = xfs_dir2_leaf_addname(&args);
238 else
239 rval = xfs_dir2_node_addname(&args);
240 return rval;
241 }
242
243 /*
244 * If doing a CI lookup and case-insensitive match, dup actual name into
245 * args.value. Return EEXIST for success (ie. name found) or an error.
246 */
247 int
248 xfs_dir_cilookup_result(
249 struct xfs_da_args *args,
250 const char *name,
251 int len)
252 {
253 if (args->cmpresult == XFS_CMP_DIFFERENT)
254 return ENOENT;
255 if (args->cmpresult != XFS_CMP_CASE ||
256 !(args->op_flags & XFS_DA_OP_CILOOKUP))
257 return EEXIST;
258
259 args->value = kmem_alloc(len, KM_MAYFAIL);
260 if (!args->value)
261 return ENOMEM;
262
263 memcpy(args->value, name, len);
264 args->valuelen = len;
265 return EEXIST;
266 }
267
268 /*
269 * Lookup a name in a directory, give back the inode number.
270 * If ci_name is not NULL, returns the actual name in ci_name if it differs
271 * to name, or ci_name->name is set to NULL for an exact match.
272 */
273
274 int
275 xfs_dir_lookup(
276 xfs_trans_t *tp,
277 xfs_inode_t *dp,
278 struct xfs_name *name,
279 xfs_ino_t *inum, /* out: inode number */
280 struct xfs_name *ci_name) /* out: actual name if CI match */
281 {
282 xfs_da_args_t args;
283 int rval;
284 int v; /* type-checking value */
285
286 ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
287 XFS_STATS_INC(xs_dir_lookup);
288
289 memset(&args, 0, sizeof(xfs_da_args_t));
290 args.name = name->name;
291 args.namelen = name->len;
292 args.hashval = dp->i_mount->m_dirnameops->hashname(name);
293 args.dp = dp;
294 args.whichfork = XFS_DATA_FORK;
295 args.trans = tp;
296 args.op_flags = XFS_DA_OP_OKNOENT;
297 if (ci_name)
298 args.op_flags |= XFS_DA_OP_CILOOKUP;
299
300 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
301 rval = xfs_dir2_sf_lookup(&args);
302 else if ((rval = xfs_dir2_isblock(tp, dp, &v)))
303 return rval;
304 else if (v)
305 rval = xfs_dir2_block_lookup(&args);
306 else if ((rval = xfs_dir2_isleaf(tp, dp, &v)))
307 return rval;
308 else if (v)
309 rval = xfs_dir2_leaf_lookup(&args);
310 else
311 rval = xfs_dir2_node_lookup(&args);
312 if (rval == EEXIST)
313 rval = 0;
314 if (!rval) {
315 *inum = args.inumber;
316 if (ci_name) {
317 ci_name->name = args.value;
318 ci_name->len = args.valuelen;
319 }
320 }
321 return rval;
322 }
323
324 /*
325 * Remove an entry from a directory.
326 */
327 int
328 xfs_dir_removename(
329 xfs_trans_t *tp,
330 xfs_inode_t *dp,
331 struct xfs_name *name,
332 xfs_ino_t ino,
333 xfs_fsblock_t *first, /* bmap's firstblock */
334 xfs_bmap_free_t *flist, /* bmap's freeblock list */
335 xfs_extlen_t total) /* bmap's total block count */
336 {
337 xfs_da_args_t args;
338 int rval;
339 int v; /* type-checking value */
340
341 ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
342 XFS_STATS_INC(xs_dir_remove);
343
344 memset(&args, 0, sizeof(xfs_da_args_t));
345 args.name = name->name;
346 args.namelen = name->len;
347 args.hashval = dp->i_mount->m_dirnameops->hashname(name);
348 args.inumber = ino;
349 args.dp = dp;
350 args.firstblock = first;
351 args.flist = flist;
352 args.total = total;
353 args.whichfork = XFS_DATA_FORK;
354 args.trans = tp;
355
356 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
357 rval = xfs_dir2_sf_removename(&args);
358 else if ((rval = xfs_dir2_isblock(tp, dp, &v)))
359 return rval;
360 else if (v)
361 rval = xfs_dir2_block_removename(&args);
362 else if ((rval = xfs_dir2_isleaf(tp, dp, &v)))
363 return rval;
364 else if (v)
365 rval = xfs_dir2_leaf_removename(&args);
366 else
367 rval = xfs_dir2_node_removename(&args);
368 return rval;
369 }
370
371 /*
372 * Read a directory.
373 */
374 int
375 xfs_readdir(
376 xfs_inode_t *dp,
377 void *dirent,
378 size_t bufsize,
379 xfs_off_t *offset,
380 filldir_t filldir)
381 {
382 int rval; /* return value */
383 int v; /* type-checking value */
384
385 xfs_itrace_entry(dp);
386
387 if (XFS_FORCED_SHUTDOWN(dp->i_mount))
388 return XFS_ERROR(EIO);
389
390 ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
391 XFS_STATS_INC(xs_dir_getdents);
392
393 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
394 rval = xfs_dir2_sf_getdents(dp, dirent, offset, filldir);
395 else if ((rval = xfs_dir2_isblock(NULL, dp, &v)))
396 ;
397 else if (v)
398 rval = xfs_dir2_block_getdents(dp, dirent, offset, filldir);
399 else
400 rval = xfs_dir2_leaf_getdents(dp, dirent, bufsize, offset,
401 filldir);
402 return rval;
403 }
404
405 /*
406 * Replace the inode number of a directory entry.
407 */
408 int
409 xfs_dir_replace(
410 xfs_trans_t *tp,
411 xfs_inode_t *dp,
412 struct xfs_name *name, /* name of entry to replace */
413 xfs_ino_t inum, /* new inode number */
414 xfs_fsblock_t *first, /* bmap's firstblock */
415 xfs_bmap_free_t *flist, /* bmap's freeblock list */
416 xfs_extlen_t total) /* bmap's total block count */
417 {
418 xfs_da_args_t args;
419 int rval;
420 int v; /* type-checking value */
421
422 ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
423
424 if ((rval = xfs_dir_ino_validate(tp->t_mountp, inum)))
425 return rval;
426
427 memset(&args, 0, sizeof(xfs_da_args_t));
428 args.name = name->name;
429 args.namelen = name->len;
430 args.hashval = dp->i_mount->m_dirnameops->hashname(name);
431 args.inumber = inum;
432 args.dp = dp;
433 args.firstblock = first;
434 args.flist = flist;
435 args.total = total;
436 args.whichfork = XFS_DATA_FORK;
437 args.trans = tp;
438
439 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
440 rval = xfs_dir2_sf_replace(&args);
441 else if ((rval = xfs_dir2_isblock(tp, dp, &v)))
442 return rval;
443 else if (v)
444 rval = xfs_dir2_block_replace(&args);
445 else if ((rval = xfs_dir2_isleaf(tp, dp, &v)))
446 return rval;
447 else if (v)
448 rval = xfs_dir2_leaf_replace(&args);
449 else
450 rval = xfs_dir2_node_replace(&args);
451 return rval;
452 }
453
454 /*
455 * See if this entry can be added to the directory without allocating space.
456 * First checks that the caller couldn't reserve enough space (resblks = 0).
457 */
458 int
459 xfs_dir_canenter(
460 xfs_trans_t *tp,
461 xfs_inode_t *dp,
462 struct xfs_name *name, /* name of entry to add */
463 uint resblks)
464 {
465 xfs_da_args_t args;
466 int rval;
467 int v; /* type-checking value */
468
469 if (resblks)
470 return 0;
471
472 ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
473
474 memset(&args, 0, sizeof(xfs_da_args_t));
475 args.name = name->name;
476 args.namelen = name->len;
477 args.hashval = dp->i_mount->m_dirnameops->hashname(name);
478 args.dp = dp;
479 args.whichfork = XFS_DATA_FORK;
480 args.trans = tp;
481 args.op_flags = XFS_DA_OP_JUSTCHECK | XFS_DA_OP_ADDNAME |
482 XFS_DA_OP_OKNOENT;
483
484 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
485 rval = xfs_dir2_sf_addname(&args);
486 else if ((rval = xfs_dir2_isblock(tp, dp, &v)))
487 return rval;
488 else if (v)
489 rval = xfs_dir2_block_addname(&args);
490 else if ((rval = xfs_dir2_isleaf(tp, dp, &v)))
491 return rval;
492 else if (v)
493 rval = xfs_dir2_leaf_addname(&args);
494 else
495 rval = xfs_dir2_node_addname(&args);
496 return rval;
497 }
498
499 /*
500 * Utility routines.
501 */
502
503 /*
504 * Add a block to the directory.
505 * This routine is for data and free blocks, not leaf/node blocks
506 * which are handled by xfs_da_grow_inode.
507 */
508 int
509 xfs_dir2_grow_inode(
510 xfs_da_args_t *args,
511 int space, /* v2 dir's space XFS_DIR2_xxx_SPACE */
512 xfs_dir2_db_t *dbp) /* out: block number added */
513 {
514 xfs_fileoff_t bno; /* directory offset of new block */
515 int count; /* count of filesystem blocks */
516 xfs_inode_t *dp; /* incore directory inode */
517 int error;
518 int got; /* blocks actually mapped */
519 int i;
520 xfs_bmbt_irec_t map; /* single structure for bmap */
521 int mapi; /* mapping index */
522 xfs_bmbt_irec_t *mapp; /* bmap mapping structure(s) */
523 xfs_mount_t *mp;
524 int nmap; /* number of bmap entries */
525 xfs_trans_t *tp;
526 xfs_drfsbno_t nblks;
527
528 xfs_dir2_trace_args_s("grow_inode", args, space);
529 dp = args->dp;
530 tp = args->trans;
531 mp = dp->i_mount;
532 nblks = dp->i_d.di_nblocks;
533 /*
534 * Set lowest possible block in the space requested.
535 */
536 bno = XFS_B_TO_FSBT(mp, space * XFS_DIR2_SPACE_SIZE);
537 count = mp->m_dirblkfsbs;
538 /*
539 * Find the first hole for our block.
540 */
541 if ((error = xfs_bmap_first_unused(tp, dp, count, &bno, XFS_DATA_FORK)))
542 return error;
543 nmap = 1;
544 ASSERT(args->firstblock != NULL);
545 /*
546 * Try mapping the new block contiguously (one extent).
547 */
548 if ((error = xfs_bmapi(tp, dp, bno, count,
549 XFS_BMAPI_WRITE|XFS_BMAPI_METADATA|XFS_BMAPI_CONTIG,
550 args->firstblock, args->total, &map, &nmap,
551 args->flist, NULL)))
552 return error;
553 ASSERT(nmap <= 1);
554 if (nmap == 1) {
555 mapp = &map;
556 mapi = 1;
557 }
558 /*
559 * Didn't work and this is a multiple-fsb directory block.
560 * Try again with contiguous flag turned on.
561 */
562 else if (nmap == 0 && count > 1) {
563 xfs_fileoff_t b; /* current file offset */
564
565 /*
566 * Space for maximum number of mappings.
567 */
568 mapp = kmem_alloc(sizeof(*mapp) * count, KM_SLEEP);
569 /*
570 * Iterate until we get to the end of our block.
571 */
572 for (b = bno, mapi = 0; b < bno + count; ) {
573 int c; /* current fsb count */
574
575 /*
576 * Can't map more than MAX_NMAP at once.
577 */
578 nmap = MIN(XFS_BMAP_MAX_NMAP, count);
579 c = (int)(bno + count - b);
580 if ((error = xfs_bmapi(tp, dp, b, c,
581 XFS_BMAPI_WRITE|XFS_BMAPI_METADATA,
582 args->firstblock, args->total,
583 &mapp[mapi], &nmap, args->flist,
584 NULL))) {
585 kmem_free(mapp);
586 return error;
587 }
588 if (nmap < 1)
589 break;
590 /*
591 * Add this bunch into our table, go to the next offset.
592 */
593 mapi += nmap;
594 b = mapp[mapi - 1].br_startoff +
595 mapp[mapi - 1].br_blockcount;
596 }
597 }
598 /*
599 * Didn't work.
600 */
601 else {
602 mapi = 0;
603 mapp = NULL;
604 }
605 /*
606 * See how many fsb's we got.
607 */
608 for (i = 0, got = 0; i < mapi; i++)
609 got += mapp[i].br_blockcount;
610 /*
611 * Didn't get enough fsb's, or the first/last block's are wrong.
612 */
613 if (got != count || mapp[0].br_startoff != bno ||
614 mapp[mapi - 1].br_startoff + mapp[mapi - 1].br_blockcount !=
615 bno + count) {
616 if (mapp != &map)
617 kmem_free(mapp);
618 return XFS_ERROR(ENOSPC);
619 }
620 /*
621 * Done with the temporary mapping table.
622 */
623 if (mapp != &map)
624 kmem_free(mapp);
625
626 /* account for newly allocated blocks in reserved blocks total */
627 args->total -= dp->i_d.di_nblocks - nblks;
628 *dbp = xfs_dir2_da_to_db(mp, (xfs_dablk_t)bno);
629
630 /*
631 * Update file's size if this is the data space and it grew.
632 */
633 if (space == XFS_DIR2_DATA_SPACE) {
634 xfs_fsize_t size; /* directory file (data) size */
635
636 size = XFS_FSB_TO_B(mp, bno + count);
637 if (size > dp->i_d.di_size) {
638 dp->i_d.di_size = size;
639 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
640 }
641 }
642 return 0;
643 }
644
645 /*
646 * See if the directory is a single-block form directory.
647 */
648 int
649 xfs_dir2_isblock(
650 xfs_trans_t *tp,
651 xfs_inode_t *dp,
652 int *vp) /* out: 1 is block, 0 is not block */
653 {
654 xfs_fileoff_t last; /* last file offset */
655 xfs_mount_t *mp;
656 int rval;
657
658 mp = dp->i_mount;
659 if ((rval = xfs_bmap_last_offset(tp, dp, &last, XFS_DATA_FORK)))
660 return rval;
661 rval = XFS_FSB_TO_B(mp, last) == mp->m_dirblksize;
662 ASSERT(rval == 0 || dp->i_d.di_size == mp->m_dirblksize);
663 *vp = rval;
664 return 0;
665 }
666
667 /*
668 * See if the directory is a single-leaf form directory.
669 */
670 int
671 xfs_dir2_isleaf(
672 xfs_trans_t *tp,
673 xfs_inode_t *dp,
674 int *vp) /* out: 1 is leaf, 0 is not leaf */
675 {
676 xfs_fileoff_t last; /* last file offset */
677 xfs_mount_t *mp;
678 int rval;
679
680 mp = dp->i_mount;
681 if ((rval = xfs_bmap_last_offset(tp, dp, &last, XFS_DATA_FORK)))
682 return rval;
683 *vp = last == mp->m_dirleafblk + (1 << mp->m_sb.sb_dirblklog);
684 return 0;
685 }
686
687 /*
688 * Remove the given block from the directory.
689 * This routine is used for data and free blocks, leaf/node are done
690 * by xfs_da_shrink_inode.
691 */
692 int
693 xfs_dir2_shrink_inode(
694 xfs_da_args_t *args,
695 xfs_dir2_db_t db,
696 xfs_dabuf_t *bp)
697 {
698 xfs_fileoff_t bno; /* directory file offset */
699 xfs_dablk_t da; /* directory file offset */
700 int done; /* bunmap is finished */
701 xfs_inode_t *dp;
702 int error;
703 xfs_mount_t *mp;
704 xfs_trans_t *tp;
705
706 xfs_dir2_trace_args_db("shrink_inode", args, db, bp);
707 dp = args->dp;
708 mp = dp->i_mount;
709 tp = args->trans;
710 da = xfs_dir2_db_to_da(mp, db);
711 /*
712 * Unmap the fsblock(s).
713 */
714 if ((error = xfs_bunmapi(tp, dp, da, mp->m_dirblkfsbs,
715 XFS_BMAPI_METADATA, 0, args->firstblock, args->flist,
716 NULL, &done))) {
717 /*
718 * ENOSPC actually can happen if we're in a removename with
719 * no space reservation, and the resulting block removal
720 * would cause a bmap btree split or conversion from extents
721 * to btree. This can only happen for un-fragmented
722 * directory blocks, since you need to be punching out
723 * the middle of an extent.
724 * In this case we need to leave the block in the file,
725 * and not binval it.
726 * So the block has to be in a consistent empty state
727 * and appropriately logged.
728 * We don't free up the buffer, the caller can tell it
729 * hasn't happened since it got an error back.
730 */
731 return error;
732 }
733 ASSERT(done);
734 /*
735 * Invalidate the buffer from the transaction.
736 */
737 xfs_da_binval(tp, bp);
738 /*
739 * If it's not a data block, we're done.
740 */
741 if (db >= XFS_DIR2_LEAF_FIRSTDB(mp))
742 return 0;
743 /*
744 * If the block isn't the last one in the directory, we're done.
745 */
746 if (dp->i_d.di_size > xfs_dir2_db_off_to_byte(mp, db + 1, 0))
747 return 0;
748 bno = da;
749 if ((error = xfs_bmap_last_before(tp, dp, &bno, XFS_DATA_FORK))) {
750 /*
751 * This can't really happen unless there's kernel corruption.
752 */
753 return error;
754 }
755 if (db == mp->m_dirdatablk)
756 ASSERT(bno == 0);
757 else
758 ASSERT(bno > 0);
759 /*
760 * Set the size to the new last block.
761 */
762 dp->i_d.di_size = XFS_FSB_TO_B(mp, bno);
763 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
764 return 0;
765 }
connection oriented routing - ARCHIVE NO UPDATES HERE