xref: /linux/fs/ocfs2/resize.c (revision 95db3b255fde4e830e5f8cc011eb404023f669d4)
1 /* -*- mode: c; c-basic-offset: 8; -*-
2  * vim: noexpandtab sw=8 ts=8 sts=0:
3  *
4  * resize.c
5  *
6  * volume resize.
7  * Inspired by ext3/resize.c.
8  *
9  * Copyright (C) 2007 Oracle.  All rights reserved.
10  *
11  * This program is free software; you can redistribute it and/or
12  * modify it under the terms of the GNU General Public
13  * License as published by the Free Software Foundation; either
14  * version 2 of the License, or (at your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
19  * General Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public
22  * License along with this program; if not, write to the
23  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
24  * Boston, MA 021110-1307, USA.
25  */
26 
27 #include <linux/fs.h>
28 #include <linux/types.h>
29 
30 #include <cluster/masklog.h>
31 
32 #include "ocfs2.h"
33 
34 #include "alloc.h"
35 #include "dlmglue.h"
36 #include "inode.h"
37 #include "journal.h"
38 #include "super.h"
39 #include "sysfile.h"
40 #include "uptodate.h"
41 #include "ocfs2_trace.h"
42 
43 #include "buffer_head_io.h"
44 #include "suballoc.h"
45 #include "resize.h"
46 
47 /*
48  * Check whether there are new backup superblocks exist
49  * in the last group. If there are some, mark them or clear
50  * them in the bitmap.
51  *
52  * Return how many backups we find in the last group.
53  */
54 static u16 ocfs2_calc_new_backup_super(struct inode *inode,
55 				       struct ocfs2_group_desc *gd,
56 				       u16 cl_cpg,
57 				       u16 old_bg_clusters,
58 				       int set)
59 {
60 	int i;
61 	u16 backups = 0;
62 	u32 cluster, lgd_cluster;
63 	u64 blkno, gd_blkno, lgd_blkno = le64_to_cpu(gd->bg_blkno);
64 
65 	for (i = 0; i < OCFS2_MAX_BACKUP_SUPERBLOCKS; i++) {
66 		blkno = ocfs2_backup_super_blkno(inode->i_sb, i);
67 		cluster = ocfs2_blocks_to_clusters(inode->i_sb, blkno);
68 
69 		gd_blkno = ocfs2_which_cluster_group(inode, cluster);
70 		if (gd_blkno < lgd_blkno)
71 			continue;
72 		else if (gd_blkno > lgd_blkno)
73 			break;
74 
75 		/* check if already done backup super */
76 		lgd_cluster = ocfs2_blocks_to_clusters(inode->i_sb, lgd_blkno);
77 		lgd_cluster += old_bg_clusters;
78 		if (lgd_cluster >= cluster)
79 			continue;
80 
81 		if (set)
82 			ocfs2_set_bit(cluster % cl_cpg,
83 				      (unsigned long *)gd->bg_bitmap);
84 		else
85 			ocfs2_clear_bit(cluster % cl_cpg,
86 					(unsigned long *)gd->bg_bitmap);
87 		backups++;
88 	}
89 
90 	return backups;
91 }
92 
93 static int ocfs2_update_last_group_and_inode(handle_t *handle,
94 					     struct inode *bm_inode,
95 					     struct buffer_head *bm_bh,
96 					     struct buffer_head *group_bh,
97 					     u32 first_new_cluster,
98 					     int new_clusters)
99 {
100 	int ret = 0;
101 	struct ocfs2_super *osb = OCFS2_SB(bm_inode->i_sb);
102 	struct ocfs2_dinode *fe = (struct ocfs2_dinode *) bm_bh->b_data;
103 	struct ocfs2_chain_list *cl = &fe->id2.i_chain;
104 	struct ocfs2_chain_rec *cr;
105 	struct ocfs2_group_desc *group;
106 	u16 chain, num_bits, backups = 0;
107 	u16 cl_bpc = le16_to_cpu(cl->cl_bpc);
108 	u16 cl_cpg = le16_to_cpu(cl->cl_cpg);
109 	u16 old_bg_clusters;
110 
111 	trace_ocfs2_update_last_group_and_inode(new_clusters,
112 						first_new_cluster);
113 
114 	ret = ocfs2_journal_access_gd(handle, INODE_CACHE(bm_inode),
115 				      group_bh, OCFS2_JOURNAL_ACCESS_WRITE);
116 	if (ret < 0) {
117 		mlog_errno(ret);
118 		goto out;
119 	}
120 
121 	group = (struct ocfs2_group_desc *)group_bh->b_data;
122 
123 	old_bg_clusters = le16_to_cpu(group->bg_bits) / cl_bpc;
124 	/* update the group first. */
125 	num_bits = new_clusters * cl_bpc;
126 	le16_add_cpu(&group->bg_bits, num_bits);
127 	le16_add_cpu(&group->bg_free_bits_count, num_bits);
128 
129 	/*
130 	 * check whether there are some new backup superblocks exist in
131 	 * this group and update the group bitmap accordingly.
132 	 */
133 	if (OCFS2_HAS_COMPAT_FEATURE(osb->sb,
134 				     OCFS2_FEATURE_COMPAT_BACKUP_SB)) {
135 		backups = ocfs2_calc_new_backup_super(bm_inode,
136 						     group,
137 						     cl_cpg, old_bg_clusters, 1);
138 		le16_add_cpu(&group->bg_free_bits_count, -1 * backups);
139 	}
140 
141 	ocfs2_journal_dirty(handle, group_bh);
142 
143 	/* update the inode accordingly. */
144 	ret = ocfs2_journal_access_di(handle, INODE_CACHE(bm_inode), bm_bh,
145 				      OCFS2_JOURNAL_ACCESS_WRITE);
146 	if (ret < 0) {
147 		mlog_errno(ret);
148 		goto out_rollback;
149 	}
150 
151 	chain = le16_to_cpu(group->bg_chain);
152 	cr = (&cl->cl_recs[chain]);
153 	le32_add_cpu(&cr->c_total, num_bits);
154 	le32_add_cpu(&cr->c_free, num_bits);
155 	le32_add_cpu(&fe->id1.bitmap1.i_total, num_bits);
156 	le32_add_cpu(&fe->i_clusters, new_clusters);
157 
158 	if (backups) {
159 		le32_add_cpu(&cr->c_free, -1 * backups);
160 		le32_add_cpu(&fe->id1.bitmap1.i_used, backups);
161 	}
162 
163 	spin_lock(&OCFS2_I(bm_inode)->ip_lock);
164 	OCFS2_I(bm_inode)->ip_clusters = le32_to_cpu(fe->i_clusters);
165 	le64_add_cpu(&fe->i_size, (u64)new_clusters << osb->s_clustersize_bits);
166 	spin_unlock(&OCFS2_I(bm_inode)->ip_lock);
167 	i_size_write(bm_inode, le64_to_cpu(fe->i_size));
168 
169 	ocfs2_journal_dirty(handle, bm_bh);
170 
171 out_rollback:
172 	if (ret < 0) {
173 		ocfs2_calc_new_backup_super(bm_inode,
174 					    group,
175 					    cl_cpg, old_bg_clusters, 0);
176 		le16_add_cpu(&group->bg_free_bits_count, backups);
177 		le16_add_cpu(&group->bg_bits, -1 * num_bits);
178 		le16_add_cpu(&group->bg_free_bits_count, -1 * num_bits);
179 	}
180 out:
181 	if (ret)
182 		mlog_errno(ret);
183 	return ret;
184 }
185 
186 static int update_backups(struct inode * inode, u32 clusters, char *data)
187 {
188 	int i, ret = 0;
189 	u32 cluster;
190 	u64 blkno;
191 	struct buffer_head *backup = NULL;
192 	struct ocfs2_dinode *backup_di = NULL;
193 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
194 
195 	/* calculate the real backups we need to update. */
196 	for (i = 0; i < OCFS2_MAX_BACKUP_SUPERBLOCKS; i++) {
197 		blkno = ocfs2_backup_super_blkno(inode->i_sb, i);
198 		cluster = ocfs2_blocks_to_clusters(inode->i_sb, blkno);
199 		if (cluster >= clusters)
200 			break;
201 
202 		ret = ocfs2_read_blocks_sync(osb, blkno, 1, &backup);
203 		if (ret < 0) {
204 			mlog_errno(ret);
205 			break;
206 		}
207 
208 		memcpy(backup->b_data, data, inode->i_sb->s_blocksize);
209 
210 		backup_di = (struct ocfs2_dinode *)backup->b_data;
211 		backup_di->i_blkno = cpu_to_le64(blkno);
212 
213 		ret = ocfs2_write_super_or_backup(osb, backup);
214 		brelse(backup);
215 		backup = NULL;
216 		if (ret < 0) {
217 			mlog_errno(ret);
218 			break;
219 		}
220 	}
221 
222 	return ret;
223 }
224 
225 static void ocfs2_update_super_and_backups(struct inode *inode,
226 					   int new_clusters)
227 {
228 	int ret;
229 	u32 clusters = 0;
230 	struct buffer_head *super_bh = NULL;
231 	struct ocfs2_dinode *super_di = NULL;
232 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
233 
234 	/*
235 	 * update the superblock last.
236 	 * It doesn't matter if the write failed.
237 	 */
238 	ret = ocfs2_read_blocks_sync(osb, OCFS2_SUPER_BLOCK_BLKNO, 1,
239 				     &super_bh);
240 	if (ret < 0) {
241 		mlog_errno(ret);
242 		goto out;
243 	}
244 
245 	super_di = (struct ocfs2_dinode *)super_bh->b_data;
246 	le32_add_cpu(&super_di->i_clusters, new_clusters);
247 	clusters = le32_to_cpu(super_di->i_clusters);
248 
249 	ret = ocfs2_write_super_or_backup(osb, super_bh);
250 	if (ret < 0) {
251 		mlog_errno(ret);
252 		goto out;
253 	}
254 
255 	if (OCFS2_HAS_COMPAT_FEATURE(osb->sb, OCFS2_FEATURE_COMPAT_BACKUP_SB))
256 		ret = update_backups(inode, clusters, super_bh->b_data);
257 
258 out:
259 	brelse(super_bh);
260 	if (ret)
261 		printk(KERN_WARNING "ocfs2: Failed to update super blocks on %s"
262 			" during fs resize. This condition is not fatal,"
263 			" but fsck.ocfs2 should be run to fix it\n",
264 			osb->dev_str);
265 	return;
266 }
267 
268 /*
269  * Extend the filesystem to the new number of clusters specified.  This entry
270  * point is only used to extend the current filesystem to the end of the last
271  * existing group.
272  */
273 int ocfs2_group_extend(struct inode * inode, int new_clusters)
274 {
275 	int ret;
276 	handle_t *handle;
277 	struct buffer_head *main_bm_bh = NULL;
278 	struct buffer_head *group_bh = NULL;
279 	struct inode *main_bm_inode = NULL;
280 	struct ocfs2_dinode *fe = NULL;
281 	struct ocfs2_group_desc *group = NULL;
282 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
283 	u16 cl_bpc;
284 	u32 first_new_cluster;
285 	u64 lgd_blkno;
286 
287 	if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
288 		return -EROFS;
289 
290 	if (new_clusters < 0)
291 		return -EINVAL;
292 	else if (new_clusters == 0)
293 		return 0;
294 
295 	main_bm_inode = ocfs2_get_system_file_inode(osb,
296 						    GLOBAL_BITMAP_SYSTEM_INODE,
297 						    OCFS2_INVALID_SLOT);
298 	if (!main_bm_inode) {
299 		ret = -EINVAL;
300 		mlog_errno(ret);
301 		goto out;
302 	}
303 
304 	inode_lock(main_bm_inode);
305 
306 	ret = ocfs2_inode_lock(main_bm_inode, &main_bm_bh, 1);
307 	if (ret < 0) {
308 		mlog_errno(ret);
309 		goto out_mutex;
310 	}
311 
312 	fe = (struct ocfs2_dinode *)main_bm_bh->b_data;
313 
314 	/* main_bm_bh is validated by inode read inside ocfs2_inode_lock(),
315 	 * so any corruption is a code bug. */
316 	BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
317 
318 	if (le16_to_cpu(fe->id2.i_chain.cl_cpg) !=
319 		ocfs2_group_bitmap_size(osb->sb, 0,
320 					osb->s_feature_incompat) * 8) {
321 		mlog(ML_ERROR, "The disk is too old and small. "
322 		     "Force to do offline resize.");
323 		ret = -EINVAL;
324 		goto out_unlock;
325 	}
326 
327 	first_new_cluster = le32_to_cpu(fe->i_clusters);
328 	lgd_blkno = ocfs2_which_cluster_group(main_bm_inode,
329 					      first_new_cluster - 1);
330 
331 	ret = ocfs2_read_group_descriptor(main_bm_inode, fe, lgd_blkno,
332 					  &group_bh);
333 	if (ret < 0) {
334 		mlog_errno(ret);
335 		goto out_unlock;
336 	}
337 	group = (struct ocfs2_group_desc *)group_bh->b_data;
338 
339 	cl_bpc = le16_to_cpu(fe->id2.i_chain.cl_bpc);
340 	if (le16_to_cpu(group->bg_bits) / cl_bpc + new_clusters >
341 		le16_to_cpu(fe->id2.i_chain.cl_cpg)) {
342 		ret = -EINVAL;
343 		goto out_unlock;
344 	}
345 
346 
347 	trace_ocfs2_group_extend(
348 	     (unsigned long long)le64_to_cpu(group->bg_blkno), new_clusters);
349 
350 	handle = ocfs2_start_trans(osb, OCFS2_GROUP_EXTEND_CREDITS);
351 	if (IS_ERR(handle)) {
352 		mlog_errno(PTR_ERR(handle));
353 		ret = -EINVAL;
354 		goto out_unlock;
355 	}
356 
357 	/* update the last group descriptor and inode. */
358 	ret = ocfs2_update_last_group_and_inode(handle, main_bm_inode,
359 						main_bm_bh, group_bh,
360 						first_new_cluster,
361 						new_clusters);
362 	if (ret) {
363 		mlog_errno(ret);
364 		goto out_commit;
365 	}
366 
367 	ocfs2_update_super_and_backups(main_bm_inode, new_clusters);
368 
369 out_commit:
370 	ocfs2_commit_trans(osb, handle);
371 out_unlock:
372 	brelse(group_bh);
373 	brelse(main_bm_bh);
374 
375 	ocfs2_inode_unlock(main_bm_inode, 1);
376 
377 out_mutex:
378 	inode_unlock(main_bm_inode);
379 	iput(main_bm_inode);
380 
381 out:
382 	return ret;
383 }
384 
385 static int ocfs2_check_new_group(struct inode *inode,
386 				 struct ocfs2_dinode *di,
387 				 struct ocfs2_new_group_input *input,
388 				 struct buffer_head *group_bh)
389 {
390 	int ret;
391 	struct ocfs2_group_desc *gd =
392 		(struct ocfs2_group_desc *)group_bh->b_data;
393 	u16 cl_bpc = le16_to_cpu(di->id2.i_chain.cl_bpc);
394 
395 	ret = ocfs2_check_group_descriptor(inode->i_sb, di, group_bh);
396 	if (ret)
397 		goto out;
398 
399 	ret = -EINVAL;
400 	if (le16_to_cpu(gd->bg_chain) != input->chain)
401 		mlog(ML_ERROR, "Group descriptor # %llu has bad chain %u "
402 		     "while input has %u set.\n",
403 		     (unsigned long long)le64_to_cpu(gd->bg_blkno),
404 		     le16_to_cpu(gd->bg_chain), input->chain);
405 	else if (le16_to_cpu(gd->bg_bits) != input->clusters * cl_bpc)
406 		mlog(ML_ERROR, "Group descriptor # %llu has bit count %u but "
407 		     "input has %u clusters set\n",
408 		     (unsigned long long)le64_to_cpu(gd->bg_blkno),
409 		     le16_to_cpu(gd->bg_bits), input->clusters);
410 	else if (le16_to_cpu(gd->bg_free_bits_count) != input->frees * cl_bpc)
411 		mlog(ML_ERROR, "Group descriptor # %llu has free bit count %u "
412 		     "but it should have %u set\n",
413 		     (unsigned long long)le64_to_cpu(gd->bg_blkno),
414 		     le16_to_cpu(gd->bg_bits),
415 		     input->frees * cl_bpc);
416 	else
417 		ret = 0;
418 
419 out:
420 	return ret;
421 }
422 
423 static int ocfs2_verify_group_and_input(struct inode *inode,
424 					struct ocfs2_dinode *di,
425 					struct ocfs2_new_group_input *input,
426 					struct buffer_head *group_bh)
427 {
428 	u16 cl_count = le16_to_cpu(di->id2.i_chain.cl_count);
429 	u16 cl_cpg = le16_to_cpu(di->id2.i_chain.cl_cpg);
430 	u16 next_free = le16_to_cpu(di->id2.i_chain.cl_next_free_rec);
431 	u32 cluster = ocfs2_blocks_to_clusters(inode->i_sb, input->group);
432 	u32 total_clusters = le32_to_cpu(di->i_clusters);
433 	int ret = -EINVAL;
434 
435 	if (cluster < total_clusters)
436 		mlog(ML_ERROR, "add a group which is in the current volume.\n");
437 	else if (input->chain >= cl_count)
438 		mlog(ML_ERROR, "input chain exceeds the limit.\n");
439 	else if (next_free != cl_count && next_free != input->chain)
440 		mlog(ML_ERROR,
441 		     "the add group should be in chain %u\n", next_free);
442 	else if (total_clusters + input->clusters < total_clusters)
443 		mlog(ML_ERROR, "add group's clusters overflow.\n");
444 	else if (input->clusters > cl_cpg)
445 		mlog(ML_ERROR, "the cluster exceeds the maximum of a group\n");
446 	else if (input->frees > input->clusters)
447 		mlog(ML_ERROR, "the free cluster exceeds the total clusters\n");
448 	else if (total_clusters % cl_cpg != 0)
449 		mlog(ML_ERROR,
450 		     "the last group isn't full. Use group extend first.\n");
451 	else if (input->group != ocfs2_which_cluster_group(inode, cluster))
452 		mlog(ML_ERROR, "group blkno is invalid\n");
453 	else if ((ret = ocfs2_check_new_group(inode, di, input, group_bh)))
454 		mlog(ML_ERROR, "group descriptor check failed.\n");
455 	else
456 		ret = 0;
457 
458 	return ret;
459 }
460 
461 /* Add a new group descriptor to global_bitmap. */
462 int ocfs2_group_add(struct inode *inode, struct ocfs2_new_group_input *input)
463 {
464 	int ret;
465 	handle_t *handle;
466 	struct buffer_head *main_bm_bh = NULL;
467 	struct inode *main_bm_inode = NULL;
468 	struct ocfs2_dinode *fe = NULL;
469 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
470 	struct buffer_head *group_bh = NULL;
471 	struct ocfs2_group_desc *group = NULL;
472 	struct ocfs2_chain_list *cl;
473 	struct ocfs2_chain_rec *cr;
474 	u16 cl_bpc;
475 	u64 bg_ptr;
476 
477 	if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
478 		return -EROFS;
479 
480 	main_bm_inode = ocfs2_get_system_file_inode(osb,
481 						    GLOBAL_BITMAP_SYSTEM_INODE,
482 						    OCFS2_INVALID_SLOT);
483 	if (!main_bm_inode) {
484 		ret = -EINVAL;
485 		mlog_errno(ret);
486 		goto out;
487 	}
488 
489 	inode_lock(main_bm_inode);
490 
491 	ret = ocfs2_inode_lock(main_bm_inode, &main_bm_bh, 1);
492 	if (ret < 0) {
493 		mlog_errno(ret);
494 		goto out_mutex;
495 	}
496 
497 	fe = (struct ocfs2_dinode *)main_bm_bh->b_data;
498 
499 	if (le16_to_cpu(fe->id2.i_chain.cl_cpg) !=
500 		ocfs2_group_bitmap_size(osb->sb, 0,
501 					osb->s_feature_incompat) * 8) {
502 		mlog(ML_ERROR, "The disk is too old and small."
503 		     " Force to do offline resize.");
504 		ret = -EINVAL;
505 		goto out_unlock;
506 	}
507 
508 	ret = ocfs2_read_blocks_sync(osb, input->group, 1, &group_bh);
509 	if (ret < 0) {
510 		mlog(ML_ERROR, "Can't read the group descriptor # %llu "
511 		     "from the device.", (unsigned long long)input->group);
512 		goto out_unlock;
513 	}
514 
515 	ocfs2_set_new_buffer_uptodate(INODE_CACHE(inode), group_bh);
516 
517 	ret = ocfs2_verify_group_and_input(main_bm_inode, fe, input, group_bh);
518 	if (ret) {
519 		mlog_errno(ret);
520 		goto out_free_group_bh;
521 	}
522 
523 	trace_ocfs2_group_add((unsigned long long)input->group,
524 			       input->chain, input->clusters, input->frees);
525 
526 	handle = ocfs2_start_trans(osb, OCFS2_GROUP_ADD_CREDITS);
527 	if (IS_ERR(handle)) {
528 		mlog_errno(PTR_ERR(handle));
529 		ret = -EINVAL;
530 		goto out_free_group_bh;
531 	}
532 
533 	cl_bpc = le16_to_cpu(fe->id2.i_chain.cl_bpc);
534 	cl = &fe->id2.i_chain;
535 	cr = &cl->cl_recs[input->chain];
536 
537 	ret = ocfs2_journal_access_gd(handle, INODE_CACHE(main_bm_inode),
538 				      group_bh, OCFS2_JOURNAL_ACCESS_WRITE);
539 	if (ret < 0) {
540 		mlog_errno(ret);
541 		goto out_commit;
542 	}
543 
544 	group = (struct ocfs2_group_desc *)group_bh->b_data;
545 	bg_ptr = le64_to_cpu(group->bg_next_group);
546 	group->bg_next_group = cr->c_blkno;
547 	ocfs2_journal_dirty(handle, group_bh);
548 
549 	ret = ocfs2_journal_access_di(handle, INODE_CACHE(main_bm_inode),
550 				      main_bm_bh, OCFS2_JOURNAL_ACCESS_WRITE);
551 	if (ret < 0) {
552 		group->bg_next_group = cpu_to_le64(bg_ptr);
553 		mlog_errno(ret);
554 		goto out_commit;
555 	}
556 
557 	if (input->chain == le16_to_cpu(cl->cl_next_free_rec)) {
558 		le16_add_cpu(&cl->cl_next_free_rec, 1);
559 		memset(cr, 0, sizeof(struct ocfs2_chain_rec));
560 	}
561 
562 	cr->c_blkno = cpu_to_le64(input->group);
563 	le32_add_cpu(&cr->c_total, input->clusters * cl_bpc);
564 	le32_add_cpu(&cr->c_free, input->frees * cl_bpc);
565 
566 	le32_add_cpu(&fe->id1.bitmap1.i_total, input->clusters *cl_bpc);
567 	le32_add_cpu(&fe->id1.bitmap1.i_used,
568 		     (input->clusters - input->frees) * cl_bpc);
569 	le32_add_cpu(&fe->i_clusters, input->clusters);
570 
571 	ocfs2_journal_dirty(handle, main_bm_bh);
572 
573 	spin_lock(&OCFS2_I(main_bm_inode)->ip_lock);
574 	OCFS2_I(main_bm_inode)->ip_clusters = le32_to_cpu(fe->i_clusters);
575 	le64_add_cpu(&fe->i_size, (u64)input->clusters << osb->s_clustersize_bits);
576 	spin_unlock(&OCFS2_I(main_bm_inode)->ip_lock);
577 	i_size_write(main_bm_inode, le64_to_cpu(fe->i_size));
578 
579 	ocfs2_update_super_and_backups(main_bm_inode, input->clusters);
580 
581 out_commit:
582 	ocfs2_commit_trans(osb, handle);
583 
584 out_free_group_bh:
585 	brelse(group_bh);
586 
587 out_unlock:
588 	brelse(main_bm_bh);
589 
590 	ocfs2_inode_unlock(main_bm_inode, 1);
591 
592 out_mutex:
593 	inode_unlock(main_bm_inode);
594 	iput(main_bm_inode);
595 
596 out:
597 	return ret;
598 }
599