blob: 04e01915b86e4e4f6ab86c6056da2ebcf4050d09 [file] [log] [blame]
Mark Fashehccd979b2005-12-15 14:31:24 -08001/* -*- mode: c; c-basic-offset: 8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
3 *
4 * dir.c
5 *
6 * Creates, reads, walks and deletes directory-nodes
7 *
8 * Copyright (C) 2002, 2004 Oracle. All rights reserved.
9 *
10 * Portions of this code from linux/fs/ext3/dir.c
11 *
12 * Copyright (C) 1992, 1993, 1994, 1995
13 * Remy Card (card@masi.ibp.fr)
14 * Laboratoire MASI - Institut Blaise pascal
15 * Universite Pierre et Marie Curie (Paris VI)
16 *
17 * from
18 *
19 * linux/fs/minix/dir.c
20 *
21 * Copyright (C) 1991, 1992 Linux Torvalds
22 *
23 * This program is free software; you can redistribute it and/or
24 * modify it under the terms of the GNU General Public
25 * License as published by the Free Software Foundation; either
26 * version 2 of the License, or (at your option) any later version.
27 *
28 * This program is distributed in the hope that it will be useful,
29 * but WITHOUT ANY WARRANTY; without even the implied warranty of
30 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
31 * General Public License for more details.
32 *
33 * You should have received a copy of the GNU General Public
34 * License along with this program; if not, write to the
35 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
36 * Boston, MA 021110-1307, USA.
37 */
38
39#include <linux/fs.h>
40#include <linux/types.h>
41#include <linux/slab.h>
42#include <linux/highmem.h>
43
44#define MLOG_MASK_PREFIX ML_NAMEI
45#include <cluster/masklog.h>
46
47#include "ocfs2.h"
48
49#include "alloc.h"
50#include "dir.h"
51#include "dlmglue.h"
52#include "extent_map.h"
53#include "file.h"
54#include "inode.h"
55#include "journal.h"
56#include "namei.h"
57#include "suballoc.h"
58#include "uptodate.h"
59
60#include "buffer_head_io.h"
61
62static unsigned char ocfs2_filetype_table[] = {
63 DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
64};
65
66static int ocfs2_extend_dir(struct ocfs2_super *osb,
67 struct inode *dir,
68 struct buffer_head *parent_fe_bh,
69 struct buffer_head **new_de_bh);
70/*
71 * ocfs2_readdir()
72 *
73 */
74int ocfs2_readdir(struct file * filp, void * dirent, filldir_t filldir)
75{
76 int error = 0;
Mark Fashehaa958872006-04-21 13:49:02 -070077 unsigned long offset, blk, last_ra_blk = 0;
78 int i, stored;
Mark Fashehccd979b2005-12-15 14:31:24 -080079 struct buffer_head * bh, * tmp;
80 struct ocfs2_dir_entry * de;
81 int err;
82 struct inode *inode = filp->f_dentry->d_inode;
83 struct super_block * sb = inode->i_sb;
Mark Fashehaa958872006-04-21 13:49:02 -070084 unsigned int ra_sectors = 16;
Mark Fashehccd979b2005-12-15 14:31:24 -080085
Mark Fashehb06970532006-03-03 10:24:33 -080086 mlog_entry("dirino=%llu\n",
87 (unsigned long long)OCFS2_I(inode)->ip_blkno);
Mark Fashehccd979b2005-12-15 14:31:24 -080088
89 stored = 0;
90 bh = NULL;
91
92 error = ocfs2_meta_lock(inode, NULL, NULL, 0);
93 if (error < 0) {
94 if (error != -ENOENT)
95 mlog_errno(error);
96 /* we haven't got any yet, so propagate the error. */
97 stored = error;
Mark Fashehaa958872006-04-21 13:49:02 -070098 goto bail_nolock;
Mark Fashehccd979b2005-12-15 14:31:24 -080099 }
Mark Fashehccd979b2005-12-15 14:31:24 -0800100
101 offset = filp->f_pos & (sb->s_blocksize - 1);
102
103 while (!error && !stored && filp->f_pos < i_size_read(inode)) {
104 blk = (filp->f_pos) >> sb->s_blocksize_bits;
105 bh = ocfs2_bread(inode, blk, &err, 0);
106 if (!bh) {
Mark Fashehb06970532006-03-03 10:24:33 -0800107 mlog(ML_ERROR,
108 "directory #%llu contains a hole at offset %lld\n",
109 (unsigned long long)OCFS2_I(inode)->ip_blkno,
Mark Fashehccd979b2005-12-15 14:31:24 -0800110 filp->f_pos);
111 filp->f_pos += sb->s_blocksize - offset;
112 continue;
113 }
114
Mark Fashehaa958872006-04-21 13:49:02 -0700115 /* The idea here is to begin with 8k read-ahead and to stay
116 * 4k ahead of our current position.
117 *
118 * TODO: Use the pagecache for this. We just need to
119 * make sure it's cluster-safe... */
120 if (!last_ra_blk
121 || (((last_ra_blk - blk) << 9) <= (ra_sectors / 2))) {
122 for (i = ra_sectors >> (sb->s_blocksize_bits - 9);
Mark Fashehccd979b2005-12-15 14:31:24 -0800123 i > 0; i--) {
124 tmp = ocfs2_bread(inode, ++blk, &err, 1);
125 if (tmp)
126 brelse(tmp);
127 }
Mark Fashehaa958872006-04-21 13:49:02 -0700128 last_ra_blk = blk;
129 ra_sectors = 8;
Mark Fashehccd979b2005-12-15 14:31:24 -0800130 }
131
132revalidate:
133 /* If the dir block has changed since the last call to
134 * readdir(2), then we might be pointing to an invalid
135 * dirent right now. Scan from the start of the block
136 * to make sure. */
137 if (filp->f_version != inode->i_version) {
138 for (i = 0; i < sb->s_blocksize && i < offset; ) {
139 de = (struct ocfs2_dir_entry *) (bh->b_data + i);
140 /* It's too expensive to do a full
141 * dirent test each time round this
142 * loop, but we do have to test at
143 * least that it is non-zero. A
144 * failure will be detected in the
145 * dirent test below. */
146 if (le16_to_cpu(de->rec_len) <
147 OCFS2_DIR_REC_LEN(1))
148 break;
149 i += le16_to_cpu(de->rec_len);
150 }
151 offset = i;
152 filp->f_pos = (filp->f_pos & ~(sb->s_blocksize - 1))
153 | offset;
154 filp->f_version = inode->i_version;
155 }
156
157 while (!error && filp->f_pos < i_size_read(inode)
158 && offset < sb->s_blocksize) {
159 de = (struct ocfs2_dir_entry *) (bh->b_data + offset);
160 if (!ocfs2_check_dir_entry(inode, de, bh, offset)) {
161 /* On error, skip the f_pos to the
162 next block. */
163 filp->f_pos = (filp->f_pos |
164 (sb->s_blocksize - 1)) + 1;
165 brelse(bh);
166 goto bail;
167 }
168 offset += le16_to_cpu(de->rec_len);
169 if (le64_to_cpu(de->inode)) {
170 /* We might block in the next section
171 * if the data destination is
172 * currently swapped out. So, use a
173 * version stamp to detect whether or
174 * not the directory has been modified
175 * during the copy operation.
176 */
177 unsigned long version = filp->f_version;
178 unsigned char d_type = DT_UNKNOWN;
179
180 if (de->file_type < OCFS2_FT_MAX)
181 d_type = ocfs2_filetype_table[de->file_type];
182 error = filldir(dirent, de->name,
183 de->name_len,
184 filp->f_pos,
185 ino_from_blkno(sb, le64_to_cpu(de->inode)),
186 d_type);
187 if (error)
188 break;
189 if (version != filp->f_version)
190 goto revalidate;
191 stored ++;
192 }
193 filp->f_pos += le16_to_cpu(de->rec_len);
194 }
195 offset = 0;
196 brelse(bh);
197 }
198
199 stored = 0;
200bail:
Mark Fashehaa958872006-04-21 13:49:02 -0700201 ocfs2_meta_unlock(inode, 0);
Mark Fashehccd979b2005-12-15 14:31:24 -0800202
Mark Fashehaa958872006-04-21 13:49:02 -0700203bail_nolock:
Mark Fashehccd979b2005-12-15 14:31:24 -0800204 mlog_exit(stored);
205
206 return stored;
207}
208
209/*
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800210 * NOTE: this should always be called with parent dir i_mutex taken.
Mark Fashehccd979b2005-12-15 14:31:24 -0800211 */
212int ocfs2_find_files_on_disk(const char *name,
213 int namelen,
214 u64 *blkno,
215 struct inode *inode,
216 struct buffer_head **dirent_bh,
217 struct ocfs2_dir_entry **dirent)
218{
219 int status = -ENOENT;
Mark Fashehccd979b2005-12-15 14:31:24 -0800220
Joel Becker2b388c62006-05-10 18:28:59 -0700221 mlog_entry("(name=%.*s, blkno=%p, inode=%p, dirent_bh=%p, dirent=%p)\n",
222 namelen, name, blkno, inode, dirent_bh, dirent);
Mark Fashehccd979b2005-12-15 14:31:24 -0800223
224 *dirent_bh = ocfs2_find_entry(name, namelen, inode, dirent);
225 if (!*dirent_bh || !*dirent) {
226 status = -ENOENT;
227 goto leave;
228 }
229
230 *blkno = le64_to_cpu((*dirent)->inode);
231
232 status = 0;
233leave:
234 if (status < 0) {
235 *dirent = NULL;
236 if (*dirent_bh) {
237 brelse(*dirent_bh);
238 *dirent_bh = NULL;
239 }
240 }
241
242 mlog_exit(status);
243 return status;
244}
245
246/* Check for a name within a directory.
247 *
248 * Return 0 if the name does not exist
249 * Return -EEXIST if the directory contains the name
250 *
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800251 * Callers should have i_mutex + a cluster lock on dir
Mark Fashehccd979b2005-12-15 14:31:24 -0800252 */
253int ocfs2_check_dir_for_entry(struct inode *dir,
254 const char *name,
255 int namelen)
256{
257 int ret;
258 struct buffer_head *dirent_bh = NULL;
259 struct ocfs2_dir_entry *dirent = NULL;
260
Mark Fashehb06970532006-03-03 10:24:33 -0800261 mlog_entry("dir %llu, name '%.*s'\n",
262 (unsigned long long)OCFS2_I(dir)->ip_blkno, namelen, name);
Mark Fashehccd979b2005-12-15 14:31:24 -0800263
264 ret = -EEXIST;
265 dirent_bh = ocfs2_find_entry(name, namelen, dir, &dirent);
266 if (dirent_bh)
267 goto bail;
268
269 ret = 0;
270bail:
271 if (dirent_bh)
272 brelse(dirent_bh);
273
274 mlog_exit(ret);
275 return ret;
276}
277
278/*
279 * routine to check that the specified directory is empty (for rmdir)
280 */
281int ocfs2_empty_dir(struct inode *inode)
282{
283 unsigned long offset;
284 struct buffer_head * bh;
285 struct ocfs2_dir_entry * de, * de1;
286 struct super_block * sb;
287 int err;
288
289 sb = inode->i_sb;
290 if ((i_size_read(inode) <
291 (OCFS2_DIR_REC_LEN(1) + OCFS2_DIR_REC_LEN(2))) ||
292 !(bh = ocfs2_bread(inode, 0, &err, 0))) {
Mark Fashehb06970532006-03-03 10:24:33 -0800293 mlog(ML_ERROR, "bad directory (dir #%llu) - no data block\n",
294 (unsigned long long)OCFS2_I(inode)->ip_blkno);
Mark Fashehccd979b2005-12-15 14:31:24 -0800295 return 1;
296 }
297
298 de = (struct ocfs2_dir_entry *) bh->b_data;
299 de1 = (struct ocfs2_dir_entry *)
300 ((char *)de + le16_to_cpu(de->rec_len));
301 if ((le64_to_cpu(de->inode) != OCFS2_I(inode)->ip_blkno) ||
302 !le64_to_cpu(de1->inode) ||
303 strcmp(".", de->name) ||
304 strcmp("..", de1->name)) {
Mark Fashehb06970532006-03-03 10:24:33 -0800305 mlog(ML_ERROR, "bad directory (dir #%llu) - no `.' or `..'\n",
306 (unsigned long long)OCFS2_I(inode)->ip_blkno);
Mark Fashehccd979b2005-12-15 14:31:24 -0800307 brelse(bh);
308 return 1;
309 }
310 offset = le16_to_cpu(de->rec_len) + le16_to_cpu(de1->rec_len);
311 de = (struct ocfs2_dir_entry *)((char *)de1 + le16_to_cpu(de1->rec_len));
312 while (offset < i_size_read(inode) ) {
313 if (!bh || (void *)de >= (void *)(bh->b_data + sb->s_blocksize)) {
314 brelse(bh);
315 bh = ocfs2_bread(inode,
316 offset >> sb->s_blocksize_bits, &err, 0);
317 if (!bh) {
Mark Fashehb06970532006-03-03 10:24:33 -0800318 mlog(ML_ERROR, "dir %llu has a hole at %lu\n",
319 (unsigned long long)OCFS2_I(inode)->ip_blkno, offset);
Mark Fashehccd979b2005-12-15 14:31:24 -0800320 offset += sb->s_blocksize;
321 continue;
322 }
323 de = (struct ocfs2_dir_entry *) bh->b_data;
324 }
325 if (!ocfs2_check_dir_entry(inode, de, bh, offset)) {
326 brelse(bh);
327 return 1;
328 }
329 if (le64_to_cpu(de->inode)) {
330 brelse(bh);
331 return 0;
332 }
333 offset += le16_to_cpu(de->rec_len);
334 de = (struct ocfs2_dir_entry *)
335 ((char *)de + le16_to_cpu(de->rec_len));
336 }
337 brelse(bh);
338 return 1;
339}
340
341/* returns a bh of the 1st new block in the allocation. */
342int ocfs2_do_extend_dir(struct super_block *sb,
343 struct ocfs2_journal_handle *handle,
344 struct inode *dir,
345 struct buffer_head *parent_fe_bh,
346 struct ocfs2_alloc_context *data_ac,
347 struct ocfs2_alloc_context *meta_ac,
348 struct buffer_head **new_bh)
349{
350 int status;
351 int extend;
352 u64 p_blkno;
353
354 spin_lock(&OCFS2_I(dir)->ip_lock);
355 extend = (i_size_read(dir) == ocfs2_clusters_to_bytes(sb, OCFS2_I(dir)->ip_clusters));
356 spin_unlock(&OCFS2_I(dir)->ip_lock);
357
358 if (extend) {
359 status = ocfs2_do_extend_allocation(OCFS2_SB(sb), dir, 1,
360 parent_fe_bh, handle,
361 data_ac, meta_ac, NULL);
362 BUG_ON(status == -EAGAIN);
363 if (status < 0) {
364 mlog_errno(status);
365 goto bail;
366 }
367 }
368
369 status = ocfs2_extent_map_get_blocks(dir, (dir->i_blocks >>
370 (sb->s_blocksize_bits - 9)),
371 1, &p_blkno, NULL);
372 if (status < 0) {
373 mlog_errno(status);
374 goto bail;
375 }
376
377 *new_bh = sb_getblk(sb, p_blkno);
378 if (!*new_bh) {
379 status = -EIO;
380 mlog_errno(status);
381 goto bail;
382 }
383 status = 0;
384bail:
385 mlog_exit(status);
386 return status;
387}
388
389/* assumes you already have a cluster lock on the directory. */
390static int ocfs2_extend_dir(struct ocfs2_super *osb,
391 struct inode *dir,
392 struct buffer_head *parent_fe_bh,
393 struct buffer_head **new_de_bh)
394{
395 int status = 0;
396 int credits, num_free_extents;
397 loff_t dir_i_size;
398 struct ocfs2_dinode *fe = (struct ocfs2_dinode *) parent_fe_bh->b_data;
399 struct ocfs2_alloc_context *data_ac = NULL;
400 struct ocfs2_alloc_context *meta_ac = NULL;
401 struct ocfs2_journal_handle *handle = NULL;
402 struct buffer_head *new_bh = NULL;
403 struct ocfs2_dir_entry * de;
404 struct super_block *sb = osb->sb;
405
406 mlog_entry_void();
407
408 dir_i_size = i_size_read(dir);
Mark Fashehb06970532006-03-03 10:24:33 -0800409 mlog(0, "extending dir %llu (i_size = %lld)\n",
410 (unsigned long long)OCFS2_I(dir)->ip_blkno, dir_i_size);
Mark Fashehccd979b2005-12-15 14:31:24 -0800411
412 handle = ocfs2_alloc_handle(osb);
413 if (handle == NULL) {
414 status = -ENOMEM;
415 mlog_errno(status);
416 goto bail;
417 }
418
419 /* dir->i_size is always block aligned. */
420 spin_lock(&OCFS2_I(dir)->ip_lock);
421 if (dir_i_size == ocfs2_clusters_to_bytes(sb, OCFS2_I(dir)->ip_clusters)) {
422 spin_unlock(&OCFS2_I(dir)->ip_lock);
423 num_free_extents = ocfs2_num_free_extents(osb, dir, fe);
424 if (num_free_extents < 0) {
425 status = num_free_extents;
426 mlog_errno(status);
427 goto bail;
428 }
429
430 if (!num_free_extents) {
431 status = ocfs2_reserve_new_metadata(osb, handle,
432 fe, &meta_ac);
433 if (status < 0) {
434 if (status != -ENOSPC)
435 mlog_errno(status);
436 goto bail;
437 }
438 }
439
440 status = ocfs2_reserve_clusters(osb, handle, 1, &data_ac);
441 if (status < 0) {
442 if (status != -ENOSPC)
443 mlog_errno(status);
444 goto bail;
445 }
446
447 credits = ocfs2_calc_extend_credits(sb, fe, 1);
448 } else {
449 spin_unlock(&OCFS2_I(dir)->ip_lock);
450 credits = OCFS2_SIMPLE_DIR_EXTEND_CREDITS;
451 }
452
453 handle = ocfs2_start_trans(osb, handle, credits);
454 if (IS_ERR(handle)) {
455 status = PTR_ERR(handle);
456 handle = NULL;
457 mlog_errno(status);
458 goto bail;
459 }
460
461 status = ocfs2_do_extend_dir(osb->sb, handle, dir, parent_fe_bh,
462 data_ac, meta_ac, &new_bh);
463 if (status < 0) {
464 mlog_errno(status);
465 goto bail;
466 }
467
468 ocfs2_set_new_buffer_uptodate(dir, new_bh);
469
470 status = ocfs2_journal_access(handle, dir, new_bh,
471 OCFS2_JOURNAL_ACCESS_CREATE);
472 if (status < 0) {
473 mlog_errno(status);
474 goto bail;
475 }
476 memset(new_bh->b_data, 0, sb->s_blocksize);
477 de = (struct ocfs2_dir_entry *) new_bh->b_data;
478 de->inode = 0;
479 de->rec_len = cpu_to_le16(sb->s_blocksize);
480 status = ocfs2_journal_dirty(handle, new_bh);
481 if (status < 0) {
482 mlog_errno(status);
483 goto bail;
484 }
485
486 dir_i_size += dir->i_sb->s_blocksize;
487 i_size_write(dir, dir_i_size);
488 dir->i_blocks = ocfs2_align_bytes_to_sectors(dir_i_size);
489 status = ocfs2_mark_inode_dirty(handle, dir, parent_fe_bh);
490 if (status < 0) {
491 mlog_errno(status);
492 goto bail;
493 }
494
495 *new_de_bh = new_bh;
496 get_bh(*new_de_bh);
497bail:
498 if (handle)
499 ocfs2_commit_trans(handle);
500
501 if (data_ac)
502 ocfs2_free_alloc_context(data_ac);
503 if (meta_ac)
504 ocfs2_free_alloc_context(meta_ac);
505
506 if (new_bh)
507 brelse(new_bh);
508
509 mlog_exit(status);
510 return status;
511}
512
513/*
514 * Search the dir for a good spot, extending it if necessary. The
515 * block containing an appropriate record is returned in ret_de_bh.
516 */
517int ocfs2_prepare_dir_for_insert(struct ocfs2_super *osb,
518 struct inode *dir,
519 struct buffer_head *parent_fe_bh,
520 const char *name,
521 int namelen,
522 struct buffer_head **ret_de_bh)
523{
524 unsigned long offset;
525 struct buffer_head * bh = NULL;
526 unsigned short rec_len;
527 struct ocfs2_dinode *fe;
528 struct ocfs2_dir_entry *de;
529 struct super_block *sb;
530 int status;
531
532 mlog_entry_void();
533
Mark Fashehb06970532006-03-03 10:24:33 -0800534 mlog(0, "getting ready to insert namelen %d into dir %llu\n",
535 namelen, (unsigned long long)OCFS2_I(dir)->ip_blkno);
Mark Fashehccd979b2005-12-15 14:31:24 -0800536
537 BUG_ON(!S_ISDIR(dir->i_mode));
538 fe = (struct ocfs2_dinode *) parent_fe_bh->b_data;
539 BUG_ON(le64_to_cpu(fe->i_size) != i_size_read(dir));
540
541 sb = dir->i_sb;
542
543 if (!namelen) {
544 status = -EINVAL;
545 mlog_errno(status);
546 goto bail;
547 }
548
549 bh = ocfs2_bread(dir, 0, &status, 0);
550 if (!bh) {
551 mlog_errno(status);
552 goto bail;
553 }
554
555 rec_len = OCFS2_DIR_REC_LEN(namelen);
556 offset = 0;
557 de = (struct ocfs2_dir_entry *) bh->b_data;
558 while (1) {
559 if ((char *)de >= sb->s_blocksize + bh->b_data) {
560 brelse(bh);
561 bh = NULL;
562
563 if (i_size_read(dir) <= offset) {
564 status = ocfs2_extend_dir(osb,
565 dir,
566 parent_fe_bh,
567 &bh);
568 if (status < 0) {
569 mlog_errno(status);
570 goto bail;
571 }
572 BUG_ON(!bh);
573 *ret_de_bh = bh;
574 get_bh(*ret_de_bh);
575 goto bail;
576 }
577 bh = ocfs2_bread(dir,
578 offset >> sb->s_blocksize_bits,
579 &status,
580 0);
581 if (!bh) {
582 mlog_errno(status);
583 goto bail;
584 }
585 /* move to next block */
586 de = (struct ocfs2_dir_entry *) bh->b_data;
587 }
588 if (!ocfs2_check_dir_entry(dir, de, bh, offset)) {
589 status = -ENOENT;
590 goto bail;
591 }
592 if (ocfs2_match(namelen, name, de)) {
593 status = -EEXIST;
594 goto bail;
595 }
596 if (((le64_to_cpu(de->inode) == 0) &&
597 (le16_to_cpu(de->rec_len) >= rec_len)) ||
598 (le16_to_cpu(de->rec_len) >=
599 (OCFS2_DIR_REC_LEN(de->name_len) + rec_len))) {
600 /* Ok, we found a spot. Return this bh and let
601 * the caller actually fill it in. */
602 *ret_de_bh = bh;
603 get_bh(*ret_de_bh);
604 status = 0;
605 goto bail;
606 }
607 offset += le16_to_cpu(de->rec_len);
608 de = (struct ocfs2_dir_entry *)((char *) de + le16_to_cpu(de->rec_len));
609 }
610
611 status = 0;
612bail:
613 if (bh)
614 brelse(bh);
615
616 mlog_exit(status);
617 return status;
618}