kconfig: allow overriding symbols
[linux/fpc-iii.git] / fs / xfs / xfs_dir2.c
blobb0f1ee8fcb90abb776a8dbd53f3664d4df189fe3
1 /*
2 * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
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.
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.
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
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"
47 void
48 xfs_dir_mount(
49 xfs_mount_t *mp)
51 ASSERT(XFS_SB_VERSION_HASDIRV2(&mp->m_sb));
52 ASSERT((1 << (mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog)) <=
53 XFS_MAX_BLOCKSIZE);
54 mp->m_dirblksize = 1 << (mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog);
55 mp->m_dirblkfsbs = 1 << mp->m_sb.sb_dirblklog;
56 mp->m_dirdatablk = xfs_dir2_db_to_da(mp, XFS_DIR2_DATA_FIRSTDB(mp));
57 mp->m_dirleafblk = xfs_dir2_db_to_da(mp, XFS_DIR2_LEAF_FIRSTDB(mp));
58 mp->m_dirfreeblk = xfs_dir2_db_to_da(mp, XFS_DIR2_FREE_FIRSTDB(mp));
59 mp->m_attr_node_ents =
60 (mp->m_sb.sb_blocksize - (uint)sizeof(xfs_da_node_hdr_t)) /
61 (uint)sizeof(xfs_da_node_entry_t);
62 mp->m_dir_node_ents =
63 (mp->m_dirblksize - (uint)sizeof(xfs_da_node_hdr_t)) /
64 (uint)sizeof(xfs_da_node_entry_t);
65 mp->m_dir_magicpct = (mp->m_dirblksize * 37) / 100;
69 * Return 1 if directory contains only "." and "..".
71 int
72 xfs_dir_isempty(
73 xfs_inode_t *dp)
75 xfs_dir2_sf_t *sfp;
77 ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
78 if (dp->i_d.di_size == 0) /* might happen during shutdown. */
79 return 1;
80 if (dp->i_d.di_size > XFS_IFORK_DSIZE(dp))
81 return 0;
82 sfp = (xfs_dir2_sf_t *)dp->i_df.if_u1.if_data;
83 return !sfp->hdr.count;
87 * Validate a given inode number.
89 int
90 xfs_dir_ino_validate(
91 xfs_mount_t *mp,
92 xfs_ino_t ino)
94 xfs_agblock_t agblkno;
95 xfs_agino_t agino;
96 xfs_agnumber_t agno;
97 int ino_ok;
98 int ioff;
100 agno = XFS_INO_TO_AGNO(mp, ino);
101 agblkno = XFS_INO_TO_AGBNO(mp, ino);
102 ioff = XFS_INO_TO_OFFSET(mp, ino);
103 agino = XFS_OFFBNO_TO_AGINO(mp, agblkno, ioff);
104 ino_ok =
105 agno < mp->m_sb.sb_agcount &&
106 agblkno < mp->m_sb.sb_agblocks &&
107 agblkno != 0 &&
108 ioff < (1 << mp->m_sb.sb_inopblog) &&
109 XFS_AGINO_TO_INO(mp, agno, agino) == ino;
110 if (unlikely(XFS_TEST_ERROR(!ino_ok, mp, XFS_ERRTAG_DIR_INO_VALIDATE,
111 XFS_RANDOM_DIR_INO_VALIDATE))) {
112 xfs_fs_cmn_err(CE_WARN, mp, "Invalid inode number 0x%Lx",
113 (unsigned long long) ino);
114 XFS_ERROR_REPORT("xfs_dir_ino_validate", XFS_ERRLEVEL_LOW, mp);
115 return XFS_ERROR(EFSCORRUPTED);
117 return 0;
121 * Initialize a directory with its "." and ".." entries.
124 xfs_dir_init(
125 xfs_trans_t *tp,
126 xfs_inode_t *dp,
127 xfs_inode_t *pdp)
129 xfs_da_args_t args;
130 int error;
132 memset((char *)&args, 0, sizeof(args));
133 args.dp = dp;
134 args.trans = tp;
135 ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
136 if ((error = xfs_dir_ino_validate(tp->t_mountp, pdp->i_ino)))
137 return error;
138 return xfs_dir2_sf_create(&args, pdp->i_ino);
142 Enter a name in a directory.
145 xfs_dir_createname(
146 xfs_trans_t *tp,
147 xfs_inode_t *dp,
148 char *name,
149 int namelen,
150 xfs_ino_t inum, /* new entry inode number */
151 xfs_fsblock_t *first, /* bmap's firstblock */
152 xfs_bmap_free_t *flist, /* bmap's freeblock list */
153 xfs_extlen_t total) /* bmap's total block count */
155 xfs_da_args_t args;
156 int rval;
157 int v; /* type-checking value */
159 ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
160 if ((rval = xfs_dir_ino_validate(tp->t_mountp, inum)))
161 return rval;
162 XFS_STATS_INC(xs_dir_create);
164 args.name = name;
165 args.namelen = namelen;
166 args.hashval = xfs_da_hashname(name, namelen);
167 args.inumber = inum;
168 args.dp = dp;
169 args.firstblock = first;
170 args.flist = flist;
171 args.total = total;
172 args.whichfork = XFS_DATA_FORK;
173 args.trans = tp;
174 args.justcheck = 0;
175 args.addname = args.oknoent = 1;
177 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
178 rval = xfs_dir2_sf_addname(&args);
179 else if ((rval = xfs_dir2_isblock(tp, dp, &v)))
180 return rval;
181 else if (v)
182 rval = xfs_dir2_block_addname(&args);
183 else if ((rval = xfs_dir2_isleaf(tp, dp, &v)))
184 return rval;
185 else if (v)
186 rval = xfs_dir2_leaf_addname(&args);
187 else
188 rval = xfs_dir2_node_addname(&args);
189 return rval;
193 * Lookup a name in a directory, give back the inode number.
196 xfs_dir_lookup(
197 xfs_trans_t *tp,
198 xfs_inode_t *dp,
199 char *name,
200 int namelen,
201 xfs_ino_t *inum) /* out: inode number */
203 xfs_da_args_t args;
204 int rval;
205 int v; /* type-checking value */
207 ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
208 XFS_STATS_INC(xs_dir_lookup);
210 args.name = name;
211 args.namelen = namelen;
212 args.hashval = xfs_da_hashname(name, namelen);
213 args.inumber = 0;
214 args.dp = dp;
215 args.firstblock = NULL;
216 args.flist = NULL;
217 args.total = 0;
218 args.whichfork = XFS_DATA_FORK;
219 args.trans = tp;
220 args.justcheck = args.addname = 0;
221 args.oknoent = 1;
223 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
224 rval = xfs_dir2_sf_lookup(&args);
225 else if ((rval = xfs_dir2_isblock(tp, dp, &v)))
226 return rval;
227 else if (v)
228 rval = xfs_dir2_block_lookup(&args);
229 else if ((rval = xfs_dir2_isleaf(tp, dp, &v)))
230 return rval;
231 else if (v)
232 rval = xfs_dir2_leaf_lookup(&args);
233 else
234 rval = xfs_dir2_node_lookup(&args);
235 if (rval == EEXIST)
236 rval = 0;
237 if (rval == 0)
238 *inum = args.inumber;
239 return rval;
243 * Remove an entry from a directory.
246 xfs_dir_removename(
247 xfs_trans_t *tp,
248 xfs_inode_t *dp,
249 char *name,
250 int namelen,
251 xfs_ino_t ino,
252 xfs_fsblock_t *first, /* bmap's firstblock */
253 xfs_bmap_free_t *flist, /* bmap's freeblock list */
254 xfs_extlen_t total) /* bmap's total block count */
256 xfs_da_args_t args;
257 int rval;
258 int v; /* type-checking value */
260 ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
261 XFS_STATS_INC(xs_dir_remove);
263 args.name = name;
264 args.namelen = namelen;
265 args.hashval = xfs_da_hashname(name, namelen);
266 args.inumber = ino;
267 args.dp = dp;
268 args.firstblock = first;
269 args.flist = flist;
270 args.total = total;
271 args.whichfork = XFS_DATA_FORK;
272 args.trans = tp;
273 args.justcheck = args.addname = args.oknoent = 0;
275 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
276 rval = xfs_dir2_sf_removename(&args);
277 else if ((rval = xfs_dir2_isblock(tp, dp, &v)))
278 return rval;
279 else if (v)
280 rval = xfs_dir2_block_removename(&args);
281 else if ((rval = xfs_dir2_isleaf(tp, dp, &v)))
282 return rval;
283 else if (v)
284 rval = xfs_dir2_leaf_removename(&args);
285 else
286 rval = xfs_dir2_node_removename(&args);
287 return rval;
291 * Read a directory.
294 xfs_readdir(
295 xfs_inode_t *dp,
296 void *dirent,
297 size_t bufsize,
298 xfs_off_t *offset,
299 filldir_t filldir)
301 int rval; /* return value */
302 int v; /* type-checking value */
304 vn_trace_entry(dp, __FUNCTION__, (inst_t *)__return_address);
306 if (XFS_FORCED_SHUTDOWN(dp->i_mount))
307 return XFS_ERROR(EIO);
309 ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
310 XFS_STATS_INC(xs_dir_getdents);
312 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
313 rval = xfs_dir2_sf_getdents(dp, dirent, offset, filldir);
314 else if ((rval = xfs_dir2_isblock(NULL, dp, &v)))
316 else if (v)
317 rval = xfs_dir2_block_getdents(dp, dirent, offset, filldir);
318 else
319 rval = xfs_dir2_leaf_getdents(dp, dirent, bufsize, offset,
320 filldir);
321 return rval;
325 * Replace the inode number of a directory entry.
328 xfs_dir_replace(
329 xfs_trans_t *tp,
330 xfs_inode_t *dp,
331 char *name, /* name of entry to replace */
332 int namelen,
333 xfs_ino_t inum, /* new inode number */
334 xfs_fsblock_t *first, /* bmap's firstblock */
335 xfs_bmap_free_t *flist, /* bmap's freeblock list */
336 xfs_extlen_t total) /* bmap's total block count */
338 xfs_da_args_t args;
339 int rval;
340 int v; /* type-checking value */
342 ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
344 if ((rval = xfs_dir_ino_validate(tp->t_mountp, inum)))
345 return rval;
347 args.name = name;
348 args.namelen = namelen;
349 args.hashval = xfs_da_hashname(name, namelen);
350 args.inumber = inum;
351 args.dp = dp;
352 args.firstblock = first;
353 args.flist = flist;
354 args.total = total;
355 args.whichfork = XFS_DATA_FORK;
356 args.trans = tp;
357 args.justcheck = args.addname = args.oknoent = 0;
359 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
360 rval = xfs_dir2_sf_replace(&args);
361 else if ((rval = xfs_dir2_isblock(tp, dp, &v)))
362 return rval;
363 else if (v)
364 rval = xfs_dir2_block_replace(&args);
365 else if ((rval = xfs_dir2_isleaf(tp, dp, &v)))
366 return rval;
367 else if (v)
368 rval = xfs_dir2_leaf_replace(&args);
369 else
370 rval = xfs_dir2_node_replace(&args);
371 return rval;
375 * See if this entry can be added to the directory without allocating space.
378 xfs_dir_canenter(
379 xfs_trans_t *tp,
380 xfs_inode_t *dp,
381 char *name, /* name of entry to add */
382 int namelen)
384 xfs_da_args_t args;
385 int rval;
386 int v; /* type-checking value */
388 ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
390 args.name = name;
391 args.namelen = namelen;
392 args.hashval = xfs_da_hashname(name, namelen);
393 args.inumber = 0;
394 args.dp = dp;
395 args.firstblock = NULL;
396 args.flist = NULL;
397 args.total = 0;
398 args.whichfork = XFS_DATA_FORK;
399 args.trans = tp;
400 args.justcheck = args.addname = args.oknoent = 1;
402 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
403 rval = xfs_dir2_sf_addname(&args);
404 else if ((rval = xfs_dir2_isblock(tp, dp, &v)))
405 return rval;
406 else if (v)
407 rval = xfs_dir2_block_addname(&args);
408 else if ((rval = xfs_dir2_isleaf(tp, dp, &v)))
409 return rval;
410 else if (v)
411 rval = xfs_dir2_leaf_addname(&args);
412 else
413 rval = xfs_dir2_node_addname(&args);
414 return rval;
418 * Utility routines.
422 * Add a block to the directory.
423 * This routine is for data and free blocks, not leaf/node blocks
424 * which are handled by xfs_da_grow_inode.
427 xfs_dir2_grow_inode(
428 xfs_da_args_t *args,
429 int space, /* v2 dir's space XFS_DIR2_xxx_SPACE */
430 xfs_dir2_db_t *dbp) /* out: block number added */
432 xfs_fileoff_t bno; /* directory offset of new block */
433 int count; /* count of filesystem blocks */
434 xfs_inode_t *dp; /* incore directory inode */
435 int error;
436 int got; /* blocks actually mapped */
437 int i;
438 xfs_bmbt_irec_t map; /* single structure for bmap */
439 int mapi; /* mapping index */
440 xfs_bmbt_irec_t *mapp; /* bmap mapping structure(s) */
441 xfs_mount_t *mp;
442 int nmap; /* number of bmap entries */
443 xfs_trans_t *tp;
445 xfs_dir2_trace_args_s("grow_inode", args, space);
446 dp = args->dp;
447 tp = args->trans;
448 mp = dp->i_mount;
450 * Set lowest possible block in the space requested.
452 bno = XFS_B_TO_FSBT(mp, space * XFS_DIR2_SPACE_SIZE);
453 count = mp->m_dirblkfsbs;
455 * Find the first hole for our block.
457 if ((error = xfs_bmap_first_unused(tp, dp, count, &bno, XFS_DATA_FORK)))
458 return error;
459 nmap = 1;
460 ASSERT(args->firstblock != NULL);
462 * Try mapping the new block contiguously (one extent).
464 if ((error = xfs_bmapi(tp, dp, bno, count,
465 XFS_BMAPI_WRITE|XFS_BMAPI_METADATA|XFS_BMAPI_CONTIG,
466 args->firstblock, args->total, &map, &nmap,
467 args->flist, NULL)))
468 return error;
469 ASSERT(nmap <= 1);
470 if (nmap == 1) {
471 mapp = &map;
472 mapi = 1;
475 * Didn't work and this is a multiple-fsb directory block.
476 * Try again with contiguous flag turned on.
478 else if (nmap == 0 && count > 1) {
479 xfs_fileoff_t b; /* current file offset */
482 * Space for maximum number of mappings.
484 mapp = kmem_alloc(sizeof(*mapp) * count, KM_SLEEP);
486 * Iterate until we get to the end of our block.
488 for (b = bno, mapi = 0; b < bno + count; ) {
489 int c; /* current fsb count */
492 * Can't map more than MAX_NMAP at once.
494 nmap = MIN(XFS_BMAP_MAX_NMAP, count);
495 c = (int)(bno + count - b);
496 if ((error = xfs_bmapi(tp, dp, b, c,
497 XFS_BMAPI_WRITE|XFS_BMAPI_METADATA,
498 args->firstblock, args->total,
499 &mapp[mapi], &nmap, args->flist,
500 NULL))) {
501 kmem_free(mapp, sizeof(*mapp) * count);
502 return error;
504 if (nmap < 1)
505 break;
507 * Add this bunch into our table, go to the next offset.
509 mapi += nmap;
510 b = mapp[mapi - 1].br_startoff +
511 mapp[mapi - 1].br_blockcount;
515 * Didn't work.
517 else {
518 mapi = 0;
519 mapp = NULL;
522 * See how many fsb's we got.
524 for (i = 0, got = 0; i < mapi; i++)
525 got += mapp[i].br_blockcount;
527 * Didn't get enough fsb's, or the first/last block's are wrong.
529 if (got != count || mapp[0].br_startoff != bno ||
530 mapp[mapi - 1].br_startoff + mapp[mapi - 1].br_blockcount !=
531 bno + count) {
532 if (mapp != &map)
533 kmem_free(mapp, sizeof(*mapp) * count);
534 return XFS_ERROR(ENOSPC);
537 * Done with the temporary mapping table.
539 if (mapp != &map)
540 kmem_free(mapp, sizeof(*mapp) * count);
541 *dbp = xfs_dir2_da_to_db(mp, (xfs_dablk_t)bno);
543 * Update file's size if this is the data space and it grew.
545 if (space == XFS_DIR2_DATA_SPACE) {
546 xfs_fsize_t size; /* directory file (data) size */
548 size = XFS_FSB_TO_B(mp, bno + count);
549 if (size > dp->i_d.di_size) {
550 dp->i_d.di_size = size;
551 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
554 return 0;
558 * See if the directory is a single-block form directory.
561 xfs_dir2_isblock(
562 xfs_trans_t *tp,
563 xfs_inode_t *dp,
564 int *vp) /* out: 1 is block, 0 is not block */
566 xfs_fileoff_t last; /* last file offset */
567 xfs_mount_t *mp;
568 int rval;
570 mp = dp->i_mount;
571 if ((rval = xfs_bmap_last_offset(tp, dp, &last, XFS_DATA_FORK)))
572 return rval;
573 rval = XFS_FSB_TO_B(mp, last) == mp->m_dirblksize;
574 ASSERT(rval == 0 || dp->i_d.di_size == mp->m_dirblksize);
575 *vp = rval;
576 return 0;
580 * See if the directory is a single-leaf form directory.
583 xfs_dir2_isleaf(
584 xfs_trans_t *tp,
585 xfs_inode_t *dp,
586 int *vp) /* out: 1 is leaf, 0 is not leaf */
588 xfs_fileoff_t last; /* last file offset */
589 xfs_mount_t *mp;
590 int rval;
592 mp = dp->i_mount;
593 if ((rval = xfs_bmap_last_offset(tp, dp, &last, XFS_DATA_FORK)))
594 return rval;
595 *vp = last == mp->m_dirleafblk + (1 << mp->m_sb.sb_dirblklog);
596 return 0;
600 * Remove the given block from the directory.
601 * This routine is used for data and free blocks, leaf/node are done
602 * by xfs_da_shrink_inode.
605 xfs_dir2_shrink_inode(
606 xfs_da_args_t *args,
607 xfs_dir2_db_t db,
608 xfs_dabuf_t *bp)
610 xfs_fileoff_t bno; /* directory file offset */
611 xfs_dablk_t da; /* directory file offset */
612 int done; /* bunmap is finished */
613 xfs_inode_t *dp;
614 int error;
615 xfs_mount_t *mp;
616 xfs_trans_t *tp;
618 xfs_dir2_trace_args_db("shrink_inode", args, db, bp);
619 dp = args->dp;
620 mp = dp->i_mount;
621 tp = args->trans;
622 da = xfs_dir2_db_to_da(mp, db);
624 * Unmap the fsblock(s).
626 if ((error = xfs_bunmapi(tp, dp, da, mp->m_dirblkfsbs,
627 XFS_BMAPI_METADATA, 0, args->firstblock, args->flist,
628 NULL, &done))) {
630 * ENOSPC actually can happen if we're in a removename with
631 * no space reservation, and the resulting block removal
632 * would cause a bmap btree split or conversion from extents
633 * to btree. This can only happen for un-fragmented
634 * directory blocks, since you need to be punching out
635 * the middle of an extent.
636 * In this case we need to leave the block in the file,
637 * and not binval it.
638 * So the block has to be in a consistent empty state
639 * and appropriately logged.
640 * We don't free up the buffer, the caller can tell it
641 * hasn't happened since it got an error back.
643 return error;
645 ASSERT(done);
647 * Invalidate the buffer from the transaction.
649 xfs_da_binval(tp, bp);
651 * If it's not a data block, we're done.
653 if (db >= XFS_DIR2_LEAF_FIRSTDB(mp))
654 return 0;
656 * If the block isn't the last one in the directory, we're done.
658 if (dp->i_d.di_size > xfs_dir2_db_off_to_byte(mp, db + 1, 0))
659 return 0;
660 bno = da;
661 if ((error = xfs_bmap_last_before(tp, dp, &bno, XFS_DATA_FORK))) {
663 * This can't really happen unless there's kernel corruption.
665 return error;
667 if (db == mp->m_dirdatablk)
668 ASSERT(bno == 0);
669 else
670 ASSERT(bno > 0);
672 * Set the size to the new last block.
674 dp->i_d.di_size = XFS_FSB_TO_B(mp, bno);
675 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
676 return 0;