blob: ae47f450792f81f745d9a6a571b9b4f898adda3a [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;
77 unsigned long offset, blk;
78 int i, num, stored;
79 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;
84 int have_disk_lock = 0;
85
Mark Fashehb0697052006-03-03 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;
98 goto bail;
99 }
100 have_disk_lock = 1;
101
102 offset = filp->f_pos & (sb->s_blocksize - 1);
103
104 while (!error && !stored && filp->f_pos < i_size_read(inode)) {
105 blk = (filp->f_pos) >> sb->s_blocksize_bits;
106 bh = ocfs2_bread(inode, blk, &err, 0);
107 if (!bh) {
Mark Fashehb0697052006-03-03 10:24:33 -0800108 mlog(ML_ERROR,
109 "directory #%llu contains a hole at offset %lld\n",
110 (unsigned long long)OCFS2_I(inode)->ip_blkno,
Mark Fashehccd979b2005-12-15 14:31:24 -0800111 filp->f_pos);
112 filp->f_pos += sb->s_blocksize - offset;
113 continue;
114 }
115
116 /*
117 * Do the readahead (8k)
118 */
119 if (!offset) {
120 for (i = 16 >> (sb->s_blocksize_bits - 9), num = 0;
121 i > 0; i--) {
122 tmp = ocfs2_bread(inode, ++blk, &err, 1);
123 if (tmp)
124 brelse(tmp);
125 }
126 }
127
128revalidate:
129 /* If the dir block has changed since the last call to
130 * readdir(2), then we might be pointing to an invalid
131 * dirent right now. Scan from the start of the block
132 * to make sure. */
133 if (filp->f_version != inode->i_version) {
134 for (i = 0; i < sb->s_blocksize && i < offset; ) {
135 de = (struct ocfs2_dir_entry *) (bh->b_data + i);
136 /* It's too expensive to do a full
137 * dirent test each time round this
138 * loop, but we do have to test at
139 * least that it is non-zero. A
140 * failure will be detected in the
141 * dirent test below. */
142 if (le16_to_cpu(de->rec_len) <
143 OCFS2_DIR_REC_LEN(1))
144 break;
145 i += le16_to_cpu(de->rec_len);
146 }
147 offset = i;
148 filp->f_pos = (filp->f_pos & ~(sb->s_blocksize - 1))
149 | offset;
150 filp->f_version = inode->i_version;
151 }
152
153 while (!error && filp->f_pos < i_size_read(inode)
154 && offset < sb->s_blocksize) {
155 de = (struct ocfs2_dir_entry *) (bh->b_data + offset);
156 if (!ocfs2_check_dir_entry(inode, de, bh, offset)) {
157 /* On error, skip the f_pos to the
158 next block. */
159 filp->f_pos = (filp->f_pos |
160 (sb->s_blocksize - 1)) + 1;
161 brelse(bh);
162 goto bail;
163 }
164 offset += le16_to_cpu(de->rec_len);
165 if (le64_to_cpu(de->inode)) {
166 /* We might block in the next section
167 * if the data destination is
168 * currently swapped out. So, use a
169 * version stamp to detect whether or
170 * not the directory has been modified
171 * during the copy operation.
172 */
173 unsigned long version = filp->f_version;
174 unsigned char d_type = DT_UNKNOWN;
175
176 if (de->file_type < OCFS2_FT_MAX)
177 d_type = ocfs2_filetype_table[de->file_type];
178 error = filldir(dirent, de->name,
179 de->name_len,
180 filp->f_pos,
181 ino_from_blkno(sb, le64_to_cpu(de->inode)),
182 d_type);
183 if (error)
184 break;
185 if (version != filp->f_version)
186 goto revalidate;
187 stored ++;
188 }
189 filp->f_pos += le16_to_cpu(de->rec_len);
190 }
191 offset = 0;
192 brelse(bh);
193 }
194
195 stored = 0;
196bail:
197 if (have_disk_lock)
198 ocfs2_meta_unlock(inode, 0);
199
200 mlog_exit(stored);
201
202 return stored;
203}
204
205/*
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800206 * NOTE: this should always be called with parent dir i_mutex taken.
Mark Fashehccd979b2005-12-15 14:31:24 -0800207 */
208int ocfs2_find_files_on_disk(const char *name,
209 int namelen,
210 u64 *blkno,
211 struct inode *inode,
212 struct buffer_head **dirent_bh,
213 struct ocfs2_dir_entry **dirent)
214{
215 int status = -ENOENT;
216 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
217
Mark Fashehb0697052006-03-03 10:24:33 -0800218 mlog_entry("(osb=%p, parent=%llu, name='%.*s', blkno=%p, inode=%p)\n",
219 osb, (unsigned long long)OCFS2_I(inode)->ip_blkno,
220 namelen, name, blkno, inode);
Mark Fashehccd979b2005-12-15 14:31:24 -0800221
222 *dirent_bh = ocfs2_find_entry(name, namelen, inode, dirent);
223 if (!*dirent_bh || !*dirent) {
224 status = -ENOENT;
225 goto leave;
226 }
227
228 *blkno = le64_to_cpu((*dirent)->inode);
229
230 status = 0;
231leave:
232 if (status < 0) {
233 *dirent = NULL;
234 if (*dirent_bh) {
235 brelse(*dirent_bh);
236 *dirent_bh = NULL;
237 }
238 }
239
240 mlog_exit(status);
241 return status;
242}
243
244/* Check for a name within a directory.
245 *
246 * Return 0 if the name does not exist
247 * Return -EEXIST if the directory contains the name
248 *
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800249 * Callers should have i_mutex + a cluster lock on dir
Mark Fashehccd979b2005-12-15 14:31:24 -0800250 */
251int ocfs2_check_dir_for_entry(struct inode *dir,
252 const char *name,
253 int namelen)
254{
255 int ret;
256 struct buffer_head *dirent_bh = NULL;
257 struct ocfs2_dir_entry *dirent = NULL;
258
Mark Fashehb0697052006-03-03 10:24:33 -0800259 mlog_entry("dir %llu, name '%.*s'\n",
260 (unsigned long long)OCFS2_I(dir)->ip_blkno, namelen, name);
Mark Fashehccd979b2005-12-15 14:31:24 -0800261
262 ret = -EEXIST;
263 dirent_bh = ocfs2_find_entry(name, namelen, dir, &dirent);
264 if (dirent_bh)
265 goto bail;
266
267 ret = 0;
268bail:
269 if (dirent_bh)
270 brelse(dirent_bh);
271
272 mlog_exit(ret);
273 return ret;
274}
275
276/*
277 * routine to check that the specified directory is empty (for rmdir)
278 */
279int ocfs2_empty_dir(struct inode *inode)
280{
281 unsigned long offset;
282 struct buffer_head * bh;
283 struct ocfs2_dir_entry * de, * de1;
284 struct super_block * sb;
285 int err;
286
287 sb = inode->i_sb;
288 if ((i_size_read(inode) <
289 (OCFS2_DIR_REC_LEN(1) + OCFS2_DIR_REC_LEN(2))) ||
290 !(bh = ocfs2_bread(inode, 0, &err, 0))) {
Mark Fashehb0697052006-03-03 10:24:33 -0800291 mlog(ML_ERROR, "bad directory (dir #%llu) - no data block\n",
292 (unsigned long long)OCFS2_I(inode)->ip_blkno);
Mark Fashehccd979b2005-12-15 14:31:24 -0800293 return 1;
294 }
295
296 de = (struct ocfs2_dir_entry *) bh->b_data;
297 de1 = (struct ocfs2_dir_entry *)
298 ((char *)de + le16_to_cpu(de->rec_len));
299 if ((le64_to_cpu(de->inode) != OCFS2_I(inode)->ip_blkno) ||
300 !le64_to_cpu(de1->inode) ||
301 strcmp(".", de->name) ||
302 strcmp("..", de1->name)) {
Mark Fashehb0697052006-03-03 10:24:33 -0800303 mlog(ML_ERROR, "bad directory (dir #%llu) - no `.' or `..'\n",
304 (unsigned long long)OCFS2_I(inode)->ip_blkno);
Mark Fashehccd979b2005-12-15 14:31:24 -0800305 brelse(bh);
306 return 1;
307 }
308 offset = le16_to_cpu(de->rec_len) + le16_to_cpu(de1->rec_len);
309 de = (struct ocfs2_dir_entry *)((char *)de1 + le16_to_cpu(de1->rec_len));
310 while (offset < i_size_read(inode) ) {
311 if (!bh || (void *)de >= (void *)(bh->b_data + sb->s_blocksize)) {
312 brelse(bh);
313 bh = ocfs2_bread(inode,
314 offset >> sb->s_blocksize_bits, &err, 0);
315 if (!bh) {
Mark Fashehb0697052006-03-03 10:24:33 -0800316 mlog(ML_ERROR, "dir %llu has a hole at %lu\n",
317 (unsigned long long)OCFS2_I(inode)->ip_blkno, offset);
Mark Fashehccd979b2005-12-15 14:31:24 -0800318 offset += sb->s_blocksize;
319 continue;
320 }
321 de = (struct ocfs2_dir_entry *) bh->b_data;
322 }
323 if (!ocfs2_check_dir_entry(inode, de, bh, offset)) {
324 brelse(bh);
325 return 1;
326 }
327 if (le64_to_cpu(de->inode)) {
328 brelse(bh);
329 return 0;
330 }
331 offset += le16_to_cpu(de->rec_len);
332 de = (struct ocfs2_dir_entry *)
333 ((char *)de + le16_to_cpu(de->rec_len));
334 }
335 brelse(bh);
336 return 1;
337}
338
339/* returns a bh of the 1st new block in the allocation. */
340int ocfs2_do_extend_dir(struct super_block *sb,
341 struct ocfs2_journal_handle *handle,
342 struct inode *dir,
343 struct buffer_head *parent_fe_bh,
344 struct ocfs2_alloc_context *data_ac,
345 struct ocfs2_alloc_context *meta_ac,
346 struct buffer_head **new_bh)
347{
348 int status;
349 int extend;
350 u64 p_blkno;
351
352 spin_lock(&OCFS2_I(dir)->ip_lock);
353 extend = (i_size_read(dir) == ocfs2_clusters_to_bytes(sb, OCFS2_I(dir)->ip_clusters));
354 spin_unlock(&OCFS2_I(dir)->ip_lock);
355
356 if (extend) {
357 status = ocfs2_do_extend_allocation(OCFS2_SB(sb), dir, 1,
358 parent_fe_bh, handle,
359 data_ac, meta_ac, NULL);
360 BUG_ON(status == -EAGAIN);
361 if (status < 0) {
362 mlog_errno(status);
363 goto bail;
364 }
365 }
366
367 status = ocfs2_extent_map_get_blocks(dir, (dir->i_blocks >>
368 (sb->s_blocksize_bits - 9)),
369 1, &p_blkno, NULL);
370 if (status < 0) {
371 mlog_errno(status);
372 goto bail;
373 }
374
375 *new_bh = sb_getblk(sb, p_blkno);
376 if (!*new_bh) {
377 status = -EIO;
378 mlog_errno(status);
379 goto bail;
380 }
381 status = 0;
382bail:
383 mlog_exit(status);
384 return status;
385}
386
387/* assumes you already have a cluster lock on the directory. */
388static int ocfs2_extend_dir(struct ocfs2_super *osb,
389 struct inode *dir,
390 struct buffer_head *parent_fe_bh,
391 struct buffer_head **new_de_bh)
392{
393 int status = 0;
394 int credits, num_free_extents;
395 loff_t dir_i_size;
396 struct ocfs2_dinode *fe = (struct ocfs2_dinode *) parent_fe_bh->b_data;
397 struct ocfs2_alloc_context *data_ac = NULL;
398 struct ocfs2_alloc_context *meta_ac = NULL;
399 struct ocfs2_journal_handle *handle = NULL;
400 struct buffer_head *new_bh = NULL;
401 struct ocfs2_dir_entry * de;
402 struct super_block *sb = osb->sb;
403
404 mlog_entry_void();
405
406 dir_i_size = i_size_read(dir);
Mark Fashehb0697052006-03-03 10:24:33 -0800407 mlog(0, "extending dir %llu (i_size = %lld)\n",
408 (unsigned long long)OCFS2_I(dir)->ip_blkno, dir_i_size);
Mark Fashehccd979b2005-12-15 14:31:24 -0800409
410 handle = ocfs2_alloc_handle(osb);
411 if (handle == NULL) {
412 status = -ENOMEM;
413 mlog_errno(status);
414 goto bail;
415 }
416
417 /* dir->i_size is always block aligned. */
418 spin_lock(&OCFS2_I(dir)->ip_lock);
419 if (dir_i_size == ocfs2_clusters_to_bytes(sb, OCFS2_I(dir)->ip_clusters)) {
420 spin_unlock(&OCFS2_I(dir)->ip_lock);
421 num_free_extents = ocfs2_num_free_extents(osb, dir, fe);
422 if (num_free_extents < 0) {
423 status = num_free_extents;
424 mlog_errno(status);
425 goto bail;
426 }
427
428 if (!num_free_extents) {
429 status = ocfs2_reserve_new_metadata(osb, handle,
430 fe, &meta_ac);
431 if (status < 0) {
432 if (status != -ENOSPC)
433 mlog_errno(status);
434 goto bail;
435 }
436 }
437
438 status = ocfs2_reserve_clusters(osb, handle, 1, &data_ac);
439 if (status < 0) {
440 if (status != -ENOSPC)
441 mlog_errno(status);
442 goto bail;
443 }
444
445 credits = ocfs2_calc_extend_credits(sb, fe, 1);
446 } else {
447 spin_unlock(&OCFS2_I(dir)->ip_lock);
448 credits = OCFS2_SIMPLE_DIR_EXTEND_CREDITS;
449 }
450
451 handle = ocfs2_start_trans(osb, handle, credits);
452 if (IS_ERR(handle)) {
453 status = PTR_ERR(handle);
454 handle = NULL;
455 mlog_errno(status);
456 goto bail;
457 }
458
459 status = ocfs2_do_extend_dir(osb->sb, handle, dir, parent_fe_bh,
460 data_ac, meta_ac, &new_bh);
461 if (status < 0) {
462 mlog_errno(status);
463 goto bail;
464 }
465
466 ocfs2_set_new_buffer_uptodate(dir, new_bh);
467
468 status = ocfs2_journal_access(handle, dir, new_bh,
469 OCFS2_JOURNAL_ACCESS_CREATE);
470 if (status < 0) {
471 mlog_errno(status);
472 goto bail;
473 }
474 memset(new_bh->b_data, 0, sb->s_blocksize);
475 de = (struct ocfs2_dir_entry *) new_bh->b_data;
476 de->inode = 0;
477 de->rec_len = cpu_to_le16(sb->s_blocksize);
478 status = ocfs2_journal_dirty(handle, new_bh);
479 if (status < 0) {
480 mlog_errno(status);
481 goto bail;
482 }
483
484 dir_i_size += dir->i_sb->s_blocksize;
485 i_size_write(dir, dir_i_size);
486 dir->i_blocks = ocfs2_align_bytes_to_sectors(dir_i_size);
487 status = ocfs2_mark_inode_dirty(handle, dir, parent_fe_bh);
488 if (status < 0) {
489 mlog_errno(status);
490 goto bail;
491 }
492
493 *new_de_bh = new_bh;
494 get_bh(*new_de_bh);
495bail:
496 if (handle)
497 ocfs2_commit_trans(handle);
498
499 if (data_ac)
500 ocfs2_free_alloc_context(data_ac);
501 if (meta_ac)
502 ocfs2_free_alloc_context(meta_ac);
503
504 if (new_bh)
505 brelse(new_bh);
506
507 mlog_exit(status);
508 return status;
509}
510
511/*
512 * Search the dir for a good spot, extending it if necessary. The
513 * block containing an appropriate record is returned in ret_de_bh.
514 */
515int ocfs2_prepare_dir_for_insert(struct ocfs2_super *osb,
516 struct inode *dir,
517 struct buffer_head *parent_fe_bh,
518 const char *name,
519 int namelen,
520 struct buffer_head **ret_de_bh)
521{
522 unsigned long offset;
523 struct buffer_head * bh = NULL;
524 unsigned short rec_len;
525 struct ocfs2_dinode *fe;
526 struct ocfs2_dir_entry *de;
527 struct super_block *sb;
528 int status;
529
530 mlog_entry_void();
531
Mark Fashehb0697052006-03-03 10:24:33 -0800532 mlog(0, "getting ready to insert namelen %d into dir %llu\n",
533 namelen, (unsigned long long)OCFS2_I(dir)->ip_blkno);
Mark Fashehccd979b2005-12-15 14:31:24 -0800534
535 BUG_ON(!S_ISDIR(dir->i_mode));
536 fe = (struct ocfs2_dinode *) parent_fe_bh->b_data;
537 BUG_ON(le64_to_cpu(fe->i_size) != i_size_read(dir));
538
539 sb = dir->i_sb;
540
541 if (!namelen) {
542 status = -EINVAL;
543 mlog_errno(status);
544 goto bail;
545 }
546
547 bh = ocfs2_bread(dir, 0, &status, 0);
548 if (!bh) {
549 mlog_errno(status);
550 goto bail;
551 }
552
553 rec_len = OCFS2_DIR_REC_LEN(namelen);
554 offset = 0;
555 de = (struct ocfs2_dir_entry *) bh->b_data;
556 while (1) {
557 if ((char *)de >= sb->s_blocksize + bh->b_data) {
558 brelse(bh);
559 bh = NULL;
560
561 if (i_size_read(dir) <= offset) {
562 status = ocfs2_extend_dir(osb,
563 dir,
564 parent_fe_bh,
565 &bh);
566 if (status < 0) {
567 mlog_errno(status);
568 goto bail;
569 }
570 BUG_ON(!bh);
571 *ret_de_bh = bh;
572 get_bh(*ret_de_bh);
573 goto bail;
574 }
575 bh = ocfs2_bread(dir,
576 offset >> sb->s_blocksize_bits,
577 &status,
578 0);
579 if (!bh) {
580 mlog_errno(status);
581 goto bail;
582 }
583 /* move to next block */
584 de = (struct ocfs2_dir_entry *) bh->b_data;
585 }
586 if (!ocfs2_check_dir_entry(dir, de, bh, offset)) {
587 status = -ENOENT;
588 goto bail;
589 }
590 if (ocfs2_match(namelen, name, de)) {
591 status = -EEXIST;
592 goto bail;
593 }
594 if (((le64_to_cpu(de->inode) == 0) &&
595 (le16_to_cpu(de->rec_len) >= rec_len)) ||
596 (le16_to_cpu(de->rec_len) >=
597 (OCFS2_DIR_REC_LEN(de->name_len) + rec_len))) {
598 /* Ok, we found a spot. Return this bh and let
599 * the caller actually fill it in. */
600 *ret_de_bh = bh;
601 get_bh(*ret_de_bh);
602 status = 0;
603 goto bail;
604 }
605 offset += le16_to_cpu(de->rec_len);
606 de = (struct ocfs2_dir_entry *)((char *) de + le16_to_cpu(de->rec_len));
607 }
608
609 status = 0;
610bail:
611 if (bh)
612 brelse(bh);
613
614 mlog_exit(status);
615 return status;
616}