Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
[wrt350n-kernel.git] / fs / xfs / xfs_dir2.c
blobbe7c4251fa619e03a161cf3d66c60dd2e0518151
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"
45 #include "xfs_vnodeops.h"
48 void
49 xfs_dir_mount(
50 xfs_mount_t *mp)
52 ASSERT(XFS_SB_VERSION_HASDIRV2(&mp->m_sb));
53 ASSERT((1 << (mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog)) <=
54 XFS_MAX_BLOCKSIZE);
55 mp->m_dirblksize = 1 << (mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog);
56 mp->m_dirblkfsbs = 1 << mp->m_sb.sb_dirblklog;
57 mp->m_dirdatablk = xfs_dir2_db_to_da(mp, XFS_DIR2_DATA_FIRSTDB(mp));
58 mp->m_dirleafblk = xfs_dir2_db_to_da(mp, XFS_DIR2_LEAF_FIRSTDB(mp));
59 mp->m_dirfreeblk = xfs_dir2_db_to_da(mp, XFS_DIR2_FREE_FIRSTDB(mp));
60 mp->m_attr_node_ents =
61 (mp->m_sb.sb_blocksize - (uint)sizeof(xfs_da_node_hdr_t)) /
62 (uint)sizeof(xfs_da_node_entry_t);
63 mp->m_dir_node_ents =
64 (mp->m_dirblksize - (uint)sizeof(xfs_da_node_hdr_t)) /
65 (uint)sizeof(xfs_da_node_entry_t);
66 mp->m_dir_magicpct = (mp->m_dirblksize * 37) / 100;
70 * Return 1 if directory contains only "." and "..".
72 int
73 xfs_dir_isempty(
74 xfs_inode_t *dp)
76 xfs_dir2_sf_t *sfp;
78 ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
79 if (dp->i_d.di_size == 0) /* might happen during shutdown. */
80 return 1;
81 if (dp->i_d.di_size > XFS_IFORK_DSIZE(dp))
82 return 0;
83 sfp = (xfs_dir2_sf_t *)dp->i_df.if_u1.if_data;
84 return !sfp->hdr.count;
88 * Validate a given inode number.
90 int
91 xfs_dir_ino_validate(
92 xfs_mount_t *mp,
93 xfs_ino_t ino)
95 xfs_agblock_t agblkno;
96 xfs_agino_t agino;
97 xfs_agnumber_t agno;
98 int ino_ok;
99 int ioff;
101 agno = XFS_INO_TO_AGNO(mp, ino);
102 agblkno = XFS_INO_TO_AGBNO(mp, ino);
103 ioff = XFS_INO_TO_OFFSET(mp, ino);
104 agino = XFS_OFFBNO_TO_AGINO(mp, agblkno, ioff);
105 ino_ok =
106 agno < mp->m_sb.sb_agcount &&
107 agblkno < mp->m_sb.sb_agblocks &&
108 agblkno != 0 &&
109 ioff < (1 << mp->m_sb.sb_inopblog) &&
110 XFS_AGINO_TO_INO(mp, agno, agino) == ino;
111 if (unlikely(XFS_TEST_ERROR(!ino_ok, mp, XFS_ERRTAG_DIR_INO_VALIDATE,
112 XFS_RANDOM_DIR_INO_VALIDATE))) {
113 xfs_fs_cmn_err(CE_WARN, mp, "Invalid inode number 0x%Lx",
114 (unsigned long long) ino);
115 XFS_ERROR_REPORT("xfs_dir_ino_validate", XFS_ERRLEVEL_LOW, mp);
116 return XFS_ERROR(EFSCORRUPTED);
118 return 0;
122 * Initialize a directory with its "." and ".." entries.
125 xfs_dir_init(
126 xfs_trans_t *tp,
127 xfs_inode_t *dp,
128 xfs_inode_t *pdp)
130 xfs_da_args_t args;
131 int error;
133 memset((char *)&args, 0, sizeof(args));
134 args.dp = dp;
135 args.trans = tp;
136 ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
137 if ((error = xfs_dir_ino_validate(tp->t_mountp, pdp->i_ino)))
138 return error;
139 return xfs_dir2_sf_create(&args, pdp->i_ino);
143 Enter a name in a directory.
146 xfs_dir_createname(
147 xfs_trans_t *tp,
148 xfs_inode_t *dp,
149 char *name,
150 int namelen,
151 xfs_ino_t inum, /* new entry inode number */
152 xfs_fsblock_t *first, /* bmap's firstblock */
153 xfs_bmap_free_t *flist, /* bmap's freeblock list */
154 xfs_extlen_t total) /* bmap's total block count */
156 xfs_da_args_t args;
157 int rval;
158 int v; /* type-checking value */
160 ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
161 if ((rval = xfs_dir_ino_validate(tp->t_mountp, inum)))
162 return rval;
163 XFS_STATS_INC(xs_dir_create);
165 args.name = name;
166 args.namelen = namelen;
167 args.hashval = xfs_da_hashname(name, namelen);
168 args.inumber = inum;
169 args.dp = dp;
170 args.firstblock = first;
171 args.flist = flist;
172 args.total = total;
173 args.whichfork = XFS_DATA_FORK;
174 args.trans = tp;
175 args.justcheck = 0;
176 args.addname = args.oknoent = 1;
178 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
179 rval = xfs_dir2_sf_addname(&args);
180 else if ((rval = xfs_dir2_isblock(tp, dp, &v)))
181 return rval;
182 else if (v)
183 rval = xfs_dir2_block_addname(&args);
184 else if ((rval = xfs_dir2_isleaf(tp, dp, &v)))
185 return rval;
186 else if (v)
187 rval = xfs_dir2_leaf_addname(&args);
188 else
189 rval = xfs_dir2_node_addname(&args);
190 return rval;
194 * Lookup a name in a directory, give back the inode number.
197 xfs_dir_lookup(
198 xfs_trans_t *tp,
199 xfs_inode_t *dp,
200 char *name,
201 int namelen,
202 xfs_ino_t *inum) /* out: inode number */
204 xfs_da_args_t args;
205 int rval;
206 int v; /* type-checking value */
208 ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
209 XFS_STATS_INC(xs_dir_lookup);
211 args.name = name;
212 args.namelen = namelen;
213 args.hashval = xfs_da_hashname(name, namelen);
214 args.inumber = 0;
215 args.dp = dp;
216 args.firstblock = NULL;
217 args.flist = NULL;
218 args.total = 0;
219 args.whichfork = XFS_DATA_FORK;
220 args.trans = tp;
221 args.justcheck = args.addname = 0;
222 args.oknoent = 1;
224 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
225 rval = xfs_dir2_sf_lookup(&args);
226 else if ((rval = xfs_dir2_isblock(tp, dp, &v)))
227 return rval;
228 else if (v)
229 rval = xfs_dir2_block_lookup(&args);
230 else if ((rval = xfs_dir2_isleaf(tp, dp, &v)))
231 return rval;
232 else if (v)
233 rval = xfs_dir2_leaf_lookup(&args);
234 else
235 rval = xfs_dir2_node_lookup(&args);
236 if (rval == EEXIST)
237 rval = 0;
238 if (rval == 0)
239 *inum = args.inumber;
240 return rval;
244 * Remove an entry from a directory.
247 xfs_dir_removename(
248 xfs_trans_t *tp,
249 xfs_inode_t *dp,
250 char *name,
251 int namelen,
252 xfs_ino_t ino,
253 xfs_fsblock_t *first, /* bmap's firstblock */
254 xfs_bmap_free_t *flist, /* bmap's freeblock list */
255 xfs_extlen_t total) /* bmap's total block count */
257 xfs_da_args_t args;
258 int rval;
259 int v; /* type-checking value */
261 ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
262 XFS_STATS_INC(xs_dir_remove);
264 args.name = name;
265 args.namelen = namelen;
266 args.hashval = xfs_da_hashname(name, namelen);
267 args.inumber = ino;
268 args.dp = dp;
269 args.firstblock = first;
270 args.flist = flist;
271 args.total = total;
272 args.whichfork = XFS_DATA_FORK;
273 args.trans = tp;
274 args.justcheck = args.addname = args.oknoent = 0;
276 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
277 rval = xfs_dir2_sf_removename(&args);
278 else if ((rval = xfs_dir2_isblock(tp, dp, &v)))
279 return rval;
280 else if (v)
281 rval = xfs_dir2_block_removename(&args);
282 else if ((rval = xfs_dir2_isleaf(tp, dp, &v)))
283 return rval;
284 else if (v)
285 rval = xfs_dir2_leaf_removename(&args);
286 else
287 rval = xfs_dir2_node_removename(&args);
288 return rval;
292 * Read a directory.
295 xfs_readdir(
296 xfs_inode_t *dp,
297 void *dirent,
298 size_t bufsize,
299 xfs_off_t *offset,
300 filldir_t filldir)
302 int rval; /* return value */
303 int v; /* type-checking value */
305 xfs_itrace_entry(dp);
307 if (XFS_FORCED_SHUTDOWN(dp->i_mount))
308 return XFS_ERROR(EIO);
310 ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
311 XFS_STATS_INC(xs_dir_getdents);
313 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
314 rval = xfs_dir2_sf_getdents(dp, dirent, offset, filldir);
315 else if ((rval = xfs_dir2_isblock(NULL, dp, &v)))
317 else if (v)
318 rval = xfs_dir2_block_getdents(dp, dirent, offset, filldir);
319 else
320 rval = xfs_dir2_leaf_getdents(dp, dirent, bufsize, offset,
321 filldir);
322 return rval;
326 * Replace the inode number of a directory entry.
329 xfs_dir_replace(
330 xfs_trans_t *tp,
331 xfs_inode_t *dp,
332 char *name, /* name of entry to replace */
333 int namelen,
334 xfs_ino_t inum, /* new inode number */
335 xfs_fsblock_t *first, /* bmap's firstblock */
336 xfs_bmap_free_t *flist, /* bmap's freeblock list */
337 xfs_extlen_t total) /* bmap's total block count */
339 xfs_da_args_t args;
340 int rval;
341 int v; /* type-checking value */
343 ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
345 if ((rval = xfs_dir_ino_validate(tp->t_mountp, inum)))
346 return rval;
348 args.name = name;
349 args.namelen = namelen;
350 args.hashval = xfs_da_hashname(name, namelen);
351 args.inumber = inum;
352 args.dp = dp;
353 args.firstblock = first;
354 args.flist = flist;
355 args.total = total;
356 args.whichfork = XFS_DATA_FORK;
357 args.trans = tp;
358 args.justcheck = args.addname = args.oknoent = 0;
360 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
361 rval = xfs_dir2_sf_replace(&args);
362 else if ((rval = xfs_dir2_isblock(tp, dp, &v)))
363 return rval;
364 else if (v)
365 rval = xfs_dir2_block_replace(&args);
366 else if ((rval = xfs_dir2_isleaf(tp, dp, &v)))
367 return rval;
368 else if (v)
369 rval = xfs_dir2_leaf_replace(&args);
370 else
371 rval = xfs_dir2_node_replace(&args);
372 return rval;
376 * See if this entry can be added to the directory without allocating space.
379 xfs_dir_canenter(
380 xfs_trans_t *tp,
381 xfs_inode_t *dp,
382 char *name, /* name of entry to add */
383 int namelen)
385 xfs_da_args_t args;
386 int rval;
387 int v; /* type-checking value */
389 ASSERT((dp->i_d.di_mode & S_IFMT) == S_IFDIR);
391 args.name = name;
392 args.namelen = namelen;
393 args.hashval = xfs_da_hashname(name, namelen);
394 args.inumber = 0;
395 args.dp = dp;
396 args.firstblock = NULL;
397 args.flist = NULL;
398 args.total = 0;
399 args.whichfork = XFS_DATA_FORK;
400 args.trans = tp;
401 args.justcheck = args.addname = args.oknoent = 1;
403 if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
404 rval = xfs_dir2_sf_addname(&args);
405 else if ((rval = xfs_dir2_isblock(tp, dp, &v)))
406 return rval;
407 else if (v)
408 rval = xfs_dir2_block_addname(&args);
409 else if ((rval = xfs_dir2_isleaf(tp, dp, &v)))
410 return rval;
411 else if (v)
412 rval = xfs_dir2_leaf_addname(&args);
413 else
414 rval = xfs_dir2_node_addname(&args);
415 return rval;
419 * Utility routines.
423 * Add a block to the directory.
424 * This routine is for data and free blocks, not leaf/node blocks
425 * which are handled by xfs_da_grow_inode.
428 xfs_dir2_grow_inode(
429 xfs_da_args_t *args,
430 int space, /* v2 dir's space XFS_DIR2_xxx_SPACE */
431 xfs_dir2_db_t *dbp) /* out: block number added */
433 xfs_fileoff_t bno; /* directory offset of new block */
434 int count; /* count of filesystem blocks */
435 xfs_inode_t *dp; /* incore directory inode */
436 int error;
437 int got; /* blocks actually mapped */
438 int i;
439 xfs_bmbt_irec_t map; /* single structure for bmap */
440 int mapi; /* mapping index */
441 xfs_bmbt_irec_t *mapp; /* bmap mapping structure(s) */
442 xfs_mount_t *mp;
443 int nmap; /* number of bmap entries */
444 xfs_trans_t *tp;
446 xfs_dir2_trace_args_s("grow_inode", args, space);
447 dp = args->dp;
448 tp = args->trans;
449 mp = dp->i_mount;
451 * Set lowest possible block in the space requested.
453 bno = XFS_B_TO_FSBT(mp, space * XFS_DIR2_SPACE_SIZE);
454 count = mp->m_dirblkfsbs;
456 * Find the first hole for our block.
458 if ((error = xfs_bmap_first_unused(tp, dp, count, &bno, XFS_DATA_FORK)))
459 return error;
460 nmap = 1;
461 ASSERT(args->firstblock != NULL);
463 * Try mapping the new block contiguously (one extent).
465 if ((error = xfs_bmapi(tp, dp, bno, count,
466 XFS_BMAPI_WRITE|XFS_BMAPI_METADATA|XFS_BMAPI_CONTIG,
467 args->firstblock, args->total, &map, &nmap,
468 args->flist, NULL)))
469 return error;
470 ASSERT(nmap <= 1);
471 if (nmap == 1) {
472 mapp = &map;
473 mapi = 1;
476 * Didn't work and this is a multiple-fsb directory block.
477 * Try again with contiguous flag turned on.
479 else if (nmap == 0 && count > 1) {
480 xfs_fileoff_t b; /* current file offset */
483 * Space for maximum number of mappings.
485 mapp = kmem_alloc(sizeof(*mapp) * count, KM_SLEEP);
487 * Iterate until we get to the end of our block.
489 for (b = bno, mapi = 0; b < bno + count; ) {
490 int c; /* current fsb count */
493 * Can't map more than MAX_NMAP at once.
495 nmap = MIN(XFS_BMAP_MAX_NMAP, count);
496 c = (int)(bno + count - b);
497 if ((error = xfs_bmapi(tp, dp, b, c,
498 XFS_BMAPI_WRITE|XFS_BMAPI_METADATA,
499 args->firstblock, args->total,
500 &mapp[mapi], &nmap, args->flist,
501 NULL))) {
502 kmem_free(mapp, sizeof(*mapp) * count);
503 return error;
505 if (nmap < 1)
506 break;
508 * Add this bunch into our table, go to the next offset.
510 mapi += nmap;
511 b = mapp[mapi - 1].br_startoff +
512 mapp[mapi - 1].br_blockcount;
516 * Didn't work.
518 else {
519 mapi = 0;
520 mapp = NULL;
523 * See how many fsb's we got.
525 for (i = 0, got = 0; i < mapi; i++)
526 got += mapp[i].br_blockcount;
528 * Didn't get enough fsb's, or the first/last block's are wrong.
530 if (got != count || mapp[0].br_startoff != bno ||
531 mapp[mapi - 1].br_startoff + mapp[mapi - 1].br_blockcount !=
532 bno + count) {
533 if (mapp != &map)
534 kmem_free(mapp, sizeof(*mapp) * count);
535 return XFS_ERROR(ENOSPC);
538 * Done with the temporary mapping table.
540 if (mapp != &map)
541 kmem_free(mapp, sizeof(*mapp) * count);
542 *dbp = xfs_dir2_da_to_db(mp, (xfs_dablk_t)bno);
544 * Update file's size if this is the data space and it grew.
546 if (space == XFS_DIR2_DATA_SPACE) {
547 xfs_fsize_t size; /* directory file (data) size */
549 size = XFS_FSB_TO_B(mp, bno + count);
550 if (size > dp->i_d.di_size) {
551 dp->i_d.di_size = size;
552 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
555 return 0;
559 * See if the directory is a single-block form directory.
562 xfs_dir2_isblock(
563 xfs_trans_t *tp,
564 xfs_inode_t *dp,
565 int *vp) /* out: 1 is block, 0 is not block */
567 xfs_fileoff_t last; /* last file offset */
568 xfs_mount_t *mp;
569 int rval;
571 mp = dp->i_mount;
572 if ((rval = xfs_bmap_last_offset(tp, dp, &last, XFS_DATA_FORK)))
573 return rval;
574 rval = XFS_FSB_TO_B(mp, last) == mp->m_dirblksize;
575 ASSERT(rval == 0 || dp->i_d.di_size == mp->m_dirblksize);
576 *vp = rval;
577 return 0;
581 * See if the directory is a single-leaf form directory.
584 xfs_dir2_isleaf(
585 xfs_trans_t *tp,
586 xfs_inode_t *dp,
587 int *vp) /* out: 1 is leaf, 0 is not leaf */
589 xfs_fileoff_t last; /* last file offset */
590 xfs_mount_t *mp;
591 int rval;
593 mp = dp->i_mount;
594 if ((rval = xfs_bmap_last_offset(tp, dp, &last, XFS_DATA_FORK)))
595 return rval;
596 *vp = last == mp->m_dirleafblk + (1 << mp->m_sb.sb_dirblklog);
597 return 0;
601 * Remove the given block from the directory.
602 * This routine is used for data and free blocks, leaf/node are done
603 * by xfs_da_shrink_inode.
606 xfs_dir2_shrink_inode(
607 xfs_da_args_t *args,
608 xfs_dir2_db_t db,
609 xfs_dabuf_t *bp)
611 xfs_fileoff_t bno; /* directory file offset */
612 xfs_dablk_t da; /* directory file offset */
613 int done; /* bunmap is finished */
614 xfs_inode_t *dp;
615 int error;
616 xfs_mount_t *mp;
617 xfs_trans_t *tp;
619 xfs_dir2_trace_args_db("shrink_inode", args, db, bp);
620 dp = args->dp;
621 mp = dp->i_mount;
622 tp = args->trans;
623 da = xfs_dir2_db_to_da(mp, db);
625 * Unmap the fsblock(s).
627 if ((error = xfs_bunmapi(tp, dp, da, mp->m_dirblkfsbs,
628 XFS_BMAPI_METADATA, 0, args->firstblock, args->flist,
629 NULL, &done))) {
631 * ENOSPC actually can happen if we're in a removename with
632 * no space reservation, and the resulting block removal
633 * would cause a bmap btree split or conversion from extents
634 * to btree. This can only happen for un-fragmented
635 * directory blocks, since you need to be punching out
636 * the middle of an extent.
637 * In this case we need to leave the block in the file,
638 * and not binval it.
639 * So the block has to be in a consistent empty state
640 * and appropriately logged.
641 * We don't free up the buffer, the caller can tell it
642 * hasn't happened since it got an error back.
644 return error;
646 ASSERT(done);
648 * Invalidate the buffer from the transaction.
650 xfs_da_binval(tp, bp);
652 * If it's not a data block, we're done.
654 if (db >= XFS_DIR2_LEAF_FIRSTDB(mp))
655 return 0;
657 * If the block isn't the last one in the directory, we're done.
659 if (dp->i_d.di_size > xfs_dir2_db_off_to_byte(mp, db + 1, 0))
660 return 0;
661 bno = da;
662 if ((error = xfs_bmap_last_before(tp, dp, &bno, XFS_DATA_FORK))) {
664 * This can't really happen unless there's kernel corruption.
666 return error;
668 if (db == mp->m_dirdatablk)
669 ASSERT(bno == 0);
670 else
671 ASSERT(bno > 0);
673 * Set the size to the new last block.
675 dp->i_d.di_size = XFS_FSB_TO_B(mp, bno);
676 xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
677 return 0;