nilfs2: reject incompatible filesystem
[linux-2.6.git] / fs / nilfs2 / super.c
1 /*
2  * super.c - NILFS module and super block management.
3  *
4  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
19  *
20  * Written by Ryusuke Konishi <ryusuke@osrg.net>
21  */
22 /*
23  *  linux/fs/ext2/super.c
24  *
25  * Copyright (C) 1992, 1993, 1994, 1995
26  * Remy Card (card@masi.ibp.fr)
27  * Laboratoire MASI - Institut Blaise Pascal
28  * Universite Pierre et Marie Curie (Paris VI)
29  *
30  *  from
31  *
32  *  linux/fs/minix/inode.c
33  *
34  *  Copyright (C) 1991, 1992  Linus Torvalds
35  *
36  *  Big-endian to little-endian byte-swapping/bitmaps by
37  *        David S. Miller (davem@caip.rutgers.edu), 1995
38  */
39
40 #include <linux/module.h>
41 #include <linux/string.h>
42 #include <linux/slab.h>
43 #include <linux/init.h>
44 #include <linux/blkdev.h>
45 #include <linux/parser.h>
46 #include <linux/random.h>
47 #include <linux/crc32.h>
48 #include <linux/smp_lock.h>
49 #include <linux/vfs.h>
50 #include <linux/writeback.h>
51 #include <linux/kobject.h>
52 #include <linux/exportfs.h>
53 #include <linux/seq_file.h>
54 #include <linux/mount.h>
55 #include "nilfs.h"
56 #include "mdt.h"
57 #include "alloc.h"
58 #include "btree.h"
59 #include "btnode.h"
60 #include "page.h"
61 #include "cpfile.h"
62 #include "ifile.h"
63 #include "dat.h"
64 #include "segment.h"
65 #include "segbuf.h"
66
67 MODULE_AUTHOR("NTT Corp.");
68 MODULE_DESCRIPTION("A New Implementation of the Log-structured Filesystem "
69                    "(NILFS)");
70 MODULE_LICENSE("GPL");
71
72 struct kmem_cache *nilfs_inode_cachep;
73 struct kmem_cache *nilfs_transaction_cachep;
74 struct kmem_cache *nilfs_segbuf_cachep;
75 struct kmem_cache *nilfs_btree_path_cache;
76
77 static int nilfs_remount(struct super_block *sb, int *flags, char *data);
78
79 static void nilfs_set_error(struct nilfs_sb_info *sbi)
80 {
81         struct the_nilfs *nilfs = sbi->s_nilfs;
82         struct nilfs_super_block **sbp;
83
84         down_write(&nilfs->ns_sem);
85         if (!(nilfs->ns_mount_state & NILFS_ERROR_FS)) {
86                 nilfs->ns_mount_state |= NILFS_ERROR_FS;
87                 sbp = nilfs_prepare_super(sbi, 0);
88                 if (likely(sbp)) {
89                         sbp[0]->s_state |= cpu_to_le16(NILFS_ERROR_FS);
90                         if (sbp[1])
91                                 sbp[1]->s_state |= cpu_to_le16(NILFS_ERROR_FS);
92                         nilfs_commit_super(sbi, NILFS_SB_COMMIT_ALL);
93                 }
94         }
95         up_write(&nilfs->ns_sem);
96 }
97
98 /**
99  * nilfs_error() - report failure condition on a filesystem
100  *
101  * nilfs_error() sets an ERROR_FS flag on the superblock as well as
102  * reporting an error message.  It should be called when NILFS detects
103  * incoherences or defects of meta data on disk.  As for sustainable
104  * errors such as a single-shot I/O error, nilfs_warning() or the printk()
105  * function should be used instead.
106  *
107  * The segment constructor must not call this function because it can
108  * kill itself.
109  */
110 void nilfs_error(struct super_block *sb, const char *function,
111                  const char *fmt, ...)
112 {
113         struct nilfs_sb_info *sbi = NILFS_SB(sb);
114         va_list args;
115
116         va_start(args, fmt);
117         printk(KERN_CRIT "NILFS error (device %s): %s: ", sb->s_id, function);
118         vprintk(fmt, args);
119         printk("\n");
120         va_end(args);
121
122         if (!(sb->s_flags & MS_RDONLY)) {
123                 nilfs_set_error(sbi);
124
125                 if (nilfs_test_opt(sbi, ERRORS_RO)) {
126                         printk(KERN_CRIT "Remounting filesystem read-only\n");
127                         sb->s_flags |= MS_RDONLY;
128                 }
129         }
130
131         if (nilfs_test_opt(sbi, ERRORS_PANIC))
132                 panic("NILFS (device %s): panic forced after error\n",
133                       sb->s_id);
134 }
135
136 void nilfs_warning(struct super_block *sb, const char *function,
137                    const char *fmt, ...)
138 {
139         va_list args;
140
141         va_start(args, fmt);
142         printk(KERN_WARNING "NILFS warning (device %s): %s: ",
143                sb->s_id, function);
144         vprintk(fmt, args);
145         printk("\n");
146         va_end(args);
147 }
148
149
150 struct inode *nilfs_alloc_inode_common(struct the_nilfs *nilfs)
151 {
152         struct nilfs_inode_info *ii;
153
154         ii = kmem_cache_alloc(nilfs_inode_cachep, GFP_NOFS);
155         if (!ii)
156                 return NULL;
157         ii->i_bh = NULL;
158         ii->i_state = 0;
159         ii->vfs_inode.i_version = 1;
160         nilfs_btnode_cache_init(&ii->i_btnode_cache, nilfs->ns_bdi);
161         return &ii->vfs_inode;
162 }
163
164 struct inode *nilfs_alloc_inode(struct super_block *sb)
165 {
166         return nilfs_alloc_inode_common(NILFS_SB(sb)->s_nilfs);
167 }
168
169 void nilfs_destroy_inode(struct inode *inode)
170 {
171         kmem_cache_free(nilfs_inode_cachep, NILFS_I(inode));
172 }
173
174 static void nilfs_clear_inode(struct inode *inode)
175 {
176         struct nilfs_inode_info *ii = NILFS_I(inode);
177
178         /*
179          * Free resources allocated in nilfs_read_inode(), here.
180          */
181         BUG_ON(!list_empty(&ii->i_dirty));
182         brelse(ii->i_bh);
183         ii->i_bh = NULL;
184
185         if (test_bit(NILFS_I_BMAP, &ii->i_state))
186                 nilfs_bmap_clear(ii->i_bmap);
187
188         nilfs_btnode_cache_clear(&ii->i_btnode_cache);
189 }
190
191 static int nilfs_sync_super(struct nilfs_sb_info *sbi, int flag)
192 {
193         struct the_nilfs *nilfs = sbi->s_nilfs;
194         int err;
195         int barrier_done = 0;
196
197         if (nilfs_test_opt(sbi, BARRIER)) {
198                 set_buffer_ordered(nilfs->ns_sbh[0]);
199                 barrier_done = 1;
200         }
201  retry:
202         set_buffer_dirty(nilfs->ns_sbh[0]);
203         err = sync_dirty_buffer(nilfs->ns_sbh[0]);
204         if (err == -EOPNOTSUPP && barrier_done) {
205                 nilfs_warning(sbi->s_super, __func__,
206                               "barrier-based sync failed. "
207                               "disabling barriers\n");
208                 nilfs_clear_opt(sbi, BARRIER);
209                 barrier_done = 0;
210                 clear_buffer_ordered(nilfs->ns_sbh[0]);
211                 goto retry;
212         }
213         if (unlikely(err)) {
214                 printk(KERN_ERR
215                        "NILFS: unable to write superblock (err=%d)\n", err);
216                 if (err == -EIO && nilfs->ns_sbh[1]) {
217                         /*
218                          * sbp[0] points to newer log than sbp[1],
219                          * so copy sbp[0] to sbp[1] to take over sbp[0].
220                          */
221                         memcpy(nilfs->ns_sbp[1], nilfs->ns_sbp[0],
222                                nilfs->ns_sbsize);
223                         nilfs_fall_back_super_block(nilfs);
224                         goto retry;
225                 }
226         } else {
227                 struct nilfs_super_block *sbp = nilfs->ns_sbp[0];
228
229                 nilfs->ns_sbwcount++;
230
231                 /*
232                  * The latest segment becomes trailable from the position
233                  * written in superblock.
234                  */
235                 clear_nilfs_discontinued(nilfs);
236
237                 /* update GC protection for recent segments */
238                 if (nilfs->ns_sbh[1]) {
239                         if (flag == NILFS_SB_COMMIT_ALL) {
240                                 set_buffer_dirty(nilfs->ns_sbh[1]);
241                                 if (sync_dirty_buffer(nilfs->ns_sbh[1]) < 0)
242                                         goto out;
243                         }
244                         if (le64_to_cpu(nilfs->ns_sbp[1]->s_last_cno) <
245                             le64_to_cpu(nilfs->ns_sbp[0]->s_last_cno))
246                                 sbp = nilfs->ns_sbp[1];
247                 }
248
249                 spin_lock(&nilfs->ns_last_segment_lock);
250                 nilfs->ns_prot_seq = le64_to_cpu(sbp->s_last_seq);
251                 spin_unlock(&nilfs->ns_last_segment_lock);
252         }
253  out:
254         return err;
255 }
256
257 void nilfs_set_log_cursor(struct nilfs_super_block *sbp,
258                           struct the_nilfs *nilfs)
259 {
260         sector_t nfreeblocks;
261
262         /* nilfs->ns_sem must be locked by the caller. */
263         nilfs_count_free_blocks(nilfs, &nfreeblocks);
264         sbp->s_free_blocks_count = cpu_to_le64(nfreeblocks);
265
266         spin_lock(&nilfs->ns_last_segment_lock);
267         sbp->s_last_seq = cpu_to_le64(nilfs->ns_last_seq);
268         sbp->s_last_pseg = cpu_to_le64(nilfs->ns_last_pseg);
269         sbp->s_last_cno = cpu_to_le64(nilfs->ns_last_cno);
270         spin_unlock(&nilfs->ns_last_segment_lock);
271 }
272
273 struct nilfs_super_block **nilfs_prepare_super(struct nilfs_sb_info *sbi,
274                                                int flip)
275 {
276         struct the_nilfs *nilfs = sbi->s_nilfs;
277         struct nilfs_super_block **sbp = nilfs->ns_sbp;
278
279         /* nilfs->ns_sem must be locked by the caller. */
280         if (sbp[0]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) {
281                 if (sbp[1] &&
282                     sbp[1]->s_magic == cpu_to_le16(NILFS_SUPER_MAGIC)) {
283                         memcpy(sbp[0], sbp[1], nilfs->ns_sbsize);
284                 } else {
285                         printk(KERN_CRIT "NILFS: superblock broke on dev %s\n",
286                                sbi->s_super->s_id);
287                         return NULL;
288                 }
289         } else if (sbp[1] &&
290                    sbp[1]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) {
291                         memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
292         }
293
294         if (flip && sbp[1])
295                 nilfs_swap_super_block(nilfs);
296
297         return sbp;
298 }
299
300 int nilfs_commit_super(struct nilfs_sb_info *sbi, int flag)
301 {
302         struct the_nilfs *nilfs = sbi->s_nilfs;
303         struct nilfs_super_block **sbp = nilfs->ns_sbp;
304         time_t t;
305
306         /* nilfs->ns_sem must be locked by the caller. */
307         t = get_seconds();
308         nilfs->ns_sbwtime = t;
309         sbp[0]->s_wtime = cpu_to_le64(t);
310         sbp[0]->s_sum = 0;
311         sbp[0]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed,
312                                              (unsigned char *)sbp[0],
313                                              nilfs->ns_sbsize));
314         if (flag == NILFS_SB_COMMIT_ALL && sbp[1]) {
315                 sbp[1]->s_wtime = sbp[0]->s_wtime;
316                 sbp[1]->s_sum = 0;
317                 sbp[1]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed,
318                                             (unsigned char *)sbp[1],
319                                             nilfs->ns_sbsize));
320         }
321         clear_nilfs_sb_dirty(nilfs);
322         return nilfs_sync_super(sbi, flag);
323 }
324
325 /**
326  * nilfs_cleanup_super() - write filesystem state for cleanup
327  * @sbi: nilfs_sb_info to be unmounted or degraded to read-only
328  *
329  * This function restores state flags in the on-disk super block.
330  * This will set "clean" flag (i.e. NILFS_VALID_FS) unless the
331  * filesystem was not clean previously.
332  */
333 int nilfs_cleanup_super(struct nilfs_sb_info *sbi)
334 {
335         struct nilfs_super_block **sbp;
336         int flag = NILFS_SB_COMMIT;
337         int ret = -EIO;
338
339         sbp = nilfs_prepare_super(sbi, 0);
340         if (sbp) {
341                 sbp[0]->s_state = cpu_to_le16(sbi->s_nilfs->ns_mount_state);
342                 nilfs_set_log_cursor(sbp[0], sbi->s_nilfs);
343                 if (sbp[1] && sbp[0]->s_last_cno == sbp[1]->s_last_cno) {
344                         /*
345                          * make the "clean" flag also to the opposite
346                          * super block if both super blocks point to
347                          * the same checkpoint.
348                          */
349                         sbp[1]->s_state = sbp[0]->s_state;
350                         flag = NILFS_SB_COMMIT_ALL;
351                 }
352                 ret = nilfs_commit_super(sbi, flag);
353         }
354         return ret;
355 }
356
357 static void nilfs_put_super(struct super_block *sb)
358 {
359         struct nilfs_sb_info *sbi = NILFS_SB(sb);
360         struct the_nilfs *nilfs = sbi->s_nilfs;
361
362         lock_kernel();
363
364         nilfs_detach_segment_constructor(sbi);
365
366         if (!(sb->s_flags & MS_RDONLY)) {
367                 down_write(&nilfs->ns_sem);
368                 nilfs_cleanup_super(sbi);
369                 up_write(&nilfs->ns_sem);
370         }
371         down_write(&nilfs->ns_super_sem);
372         if (nilfs->ns_current == sbi)
373                 nilfs->ns_current = NULL;
374         up_write(&nilfs->ns_super_sem);
375
376         nilfs_detach_checkpoint(sbi);
377         put_nilfs(sbi->s_nilfs);
378         sbi->s_super = NULL;
379         sb->s_fs_info = NULL;
380         nilfs_put_sbinfo(sbi);
381
382         unlock_kernel();
383 }
384
385 static int nilfs_sync_fs(struct super_block *sb, int wait)
386 {
387         struct nilfs_sb_info *sbi = NILFS_SB(sb);
388         struct the_nilfs *nilfs = sbi->s_nilfs;
389         struct nilfs_super_block **sbp;
390         int err = 0;
391
392         /* This function is called when super block should be written back */
393         if (wait)
394                 err = nilfs_construct_segment(sb);
395
396         down_write(&nilfs->ns_sem);
397         if (nilfs_sb_dirty(nilfs)) {
398                 sbp = nilfs_prepare_super(sbi, nilfs_sb_will_flip(nilfs));
399                 if (likely(sbp)) {
400                         nilfs_set_log_cursor(sbp[0], nilfs);
401                         nilfs_commit_super(sbi, NILFS_SB_COMMIT);
402                 }
403         }
404         up_write(&nilfs->ns_sem);
405
406         return err;
407 }
408
409 int nilfs_attach_checkpoint(struct nilfs_sb_info *sbi, __u64 cno)
410 {
411         struct the_nilfs *nilfs = sbi->s_nilfs;
412         struct nilfs_checkpoint *raw_cp;
413         struct buffer_head *bh_cp;
414         int err;
415
416         down_write(&nilfs->ns_super_sem);
417         list_add(&sbi->s_list, &nilfs->ns_supers);
418         up_write(&nilfs->ns_super_sem);
419
420         sbi->s_ifile = nilfs_ifile_new(sbi, nilfs->ns_inode_size);
421         if (!sbi->s_ifile)
422                 return -ENOMEM;
423
424         down_read(&nilfs->ns_segctor_sem);
425         err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, cno, 0, &raw_cp,
426                                           &bh_cp);
427         up_read(&nilfs->ns_segctor_sem);
428         if (unlikely(err)) {
429                 if (err == -ENOENT || err == -EINVAL) {
430                         printk(KERN_ERR
431                                "NILFS: Invalid checkpoint "
432                                "(checkpoint number=%llu)\n",
433                                (unsigned long long)cno);
434                         err = -EINVAL;
435                 }
436                 goto failed;
437         }
438         err = nilfs_read_inode_common(sbi->s_ifile, &raw_cp->cp_ifile_inode);
439         if (unlikely(err))
440                 goto failed_bh;
441         atomic_set(&sbi->s_inodes_count, le64_to_cpu(raw_cp->cp_inodes_count));
442         atomic_set(&sbi->s_blocks_count, le64_to_cpu(raw_cp->cp_blocks_count));
443
444         nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp);
445         return 0;
446
447  failed_bh:
448         nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp);
449  failed:
450         nilfs_mdt_destroy(sbi->s_ifile);
451         sbi->s_ifile = NULL;
452
453         down_write(&nilfs->ns_super_sem);
454         list_del_init(&sbi->s_list);
455         up_write(&nilfs->ns_super_sem);
456
457         return err;
458 }
459
460 void nilfs_detach_checkpoint(struct nilfs_sb_info *sbi)
461 {
462         struct the_nilfs *nilfs = sbi->s_nilfs;
463
464         nilfs_mdt_destroy(sbi->s_ifile);
465         sbi->s_ifile = NULL;
466         down_write(&nilfs->ns_super_sem);
467         list_del_init(&sbi->s_list);
468         up_write(&nilfs->ns_super_sem);
469 }
470
471 static int nilfs_statfs(struct dentry *dentry, struct kstatfs *buf)
472 {
473         struct super_block *sb = dentry->d_sb;
474         struct nilfs_sb_info *sbi = NILFS_SB(sb);
475         struct the_nilfs *nilfs = sbi->s_nilfs;
476         u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
477         unsigned long long blocks;
478         unsigned long overhead;
479         unsigned long nrsvblocks;
480         sector_t nfreeblocks;
481         int err;
482
483         /*
484          * Compute all of the segment blocks
485          *
486          * The blocks before first segment and after last segment
487          * are excluded.
488          */
489         blocks = nilfs->ns_blocks_per_segment * nilfs->ns_nsegments
490                 - nilfs->ns_first_data_block;
491         nrsvblocks = nilfs->ns_nrsvsegs * nilfs->ns_blocks_per_segment;
492
493         /*
494          * Compute the overhead
495          *
496          * When distributing meta data blocks outside segment structure,
497          * We must count them as the overhead.
498          */
499         overhead = 0;
500
501         err = nilfs_count_free_blocks(nilfs, &nfreeblocks);
502         if (unlikely(err))
503                 return err;
504
505         buf->f_type = NILFS_SUPER_MAGIC;
506         buf->f_bsize = sb->s_blocksize;
507         buf->f_blocks = blocks - overhead;
508         buf->f_bfree = nfreeblocks;
509         buf->f_bavail = (buf->f_bfree >= nrsvblocks) ?
510                 (buf->f_bfree - nrsvblocks) : 0;
511         buf->f_files = atomic_read(&sbi->s_inodes_count);
512         buf->f_ffree = 0; /* nilfs_count_free_inodes(sb); */
513         buf->f_namelen = NILFS_NAME_LEN;
514         buf->f_fsid.val[0] = (u32)id;
515         buf->f_fsid.val[1] = (u32)(id >> 32);
516
517         return 0;
518 }
519
520 static int nilfs_show_options(struct seq_file *seq, struct vfsmount *vfs)
521 {
522         struct super_block *sb = vfs->mnt_sb;
523         struct nilfs_sb_info *sbi = NILFS_SB(sb);
524
525         if (!nilfs_test_opt(sbi, BARRIER))
526                 seq_puts(seq, ",nobarrier");
527         if (nilfs_test_opt(sbi, SNAPSHOT))
528                 seq_printf(seq, ",cp=%llu",
529                            (unsigned long long int)sbi->s_snapshot_cno);
530         if (nilfs_test_opt(sbi, ERRORS_PANIC))
531                 seq_puts(seq, ",errors=panic");
532         if (nilfs_test_opt(sbi, ERRORS_CONT))
533                 seq_puts(seq, ",errors=continue");
534         if (nilfs_test_opt(sbi, STRICT_ORDER))
535                 seq_puts(seq, ",order=strict");
536         if (nilfs_test_opt(sbi, NORECOVERY))
537                 seq_puts(seq, ",norecovery");
538         if (nilfs_test_opt(sbi, DISCARD))
539                 seq_puts(seq, ",discard");
540
541         return 0;
542 }
543
544 static const struct super_operations nilfs_sops = {
545         .alloc_inode    = nilfs_alloc_inode,
546         .destroy_inode  = nilfs_destroy_inode,
547         .dirty_inode    = nilfs_dirty_inode,
548         /* .write_inode    = nilfs_write_inode, */
549         /* .put_inode      = nilfs_put_inode, */
550         /* .drop_inode    = nilfs_drop_inode, */
551         .delete_inode   = nilfs_delete_inode,
552         .put_super      = nilfs_put_super,
553         /* .write_super    = nilfs_write_super, */
554         .sync_fs        = nilfs_sync_fs,
555         /* .write_super_lockfs */
556         /* .unlockfs */
557         .statfs         = nilfs_statfs,
558         .remount_fs     = nilfs_remount,
559         .clear_inode    = nilfs_clear_inode,
560         /* .umount_begin */
561         .show_options = nilfs_show_options
562 };
563
564 static struct inode *
565 nilfs_nfs_get_inode(struct super_block *sb, u64 ino, u32 generation)
566 {
567         struct inode *inode;
568
569         if (ino < NILFS_FIRST_INO(sb) && ino != NILFS_ROOT_INO &&
570             ino != NILFS_SKETCH_INO)
571                 return ERR_PTR(-ESTALE);
572
573         inode = nilfs_iget(sb, ino);
574         if (IS_ERR(inode))
575                 return ERR_CAST(inode);
576         if (generation && inode->i_generation != generation) {
577                 iput(inode);
578                 return ERR_PTR(-ESTALE);
579         }
580
581         return inode;
582 }
583
584 static struct dentry *
585 nilfs_fh_to_dentry(struct super_block *sb, struct fid *fid, int fh_len,
586                    int fh_type)
587 {
588         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
589                                     nilfs_nfs_get_inode);
590 }
591
592 static struct dentry *
593 nilfs_fh_to_parent(struct super_block *sb, struct fid *fid, int fh_len,
594                    int fh_type)
595 {
596         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
597                                     nilfs_nfs_get_inode);
598 }
599
600 static const struct export_operations nilfs_export_ops = {
601         .fh_to_dentry = nilfs_fh_to_dentry,
602         .fh_to_parent = nilfs_fh_to_parent,
603         .get_parent = nilfs_get_parent,
604 };
605
606 enum {
607         Opt_err_cont, Opt_err_panic, Opt_err_ro,
608         Opt_barrier, Opt_nobarrier, Opt_snapshot, Opt_order, Opt_norecovery,
609         Opt_discard, Opt_nodiscard, Opt_err,
610 };
611
612 static match_table_t tokens = {
613         {Opt_err_cont, "errors=continue"},
614         {Opt_err_panic, "errors=panic"},
615         {Opt_err_ro, "errors=remount-ro"},
616         {Opt_barrier, "barrier"},
617         {Opt_nobarrier, "nobarrier"},
618         {Opt_snapshot, "cp=%u"},
619         {Opt_order, "order=%s"},
620         {Opt_norecovery, "norecovery"},
621         {Opt_discard, "discard"},
622         {Opt_nodiscard, "nodiscard"},
623         {Opt_err, NULL}
624 };
625
626 static int parse_options(char *options, struct super_block *sb, int is_remount)
627 {
628         struct nilfs_sb_info *sbi = NILFS_SB(sb);
629         char *p;
630         substring_t args[MAX_OPT_ARGS];
631         int option;
632
633         if (!options)
634                 return 1;
635
636         while ((p = strsep(&options, ",")) != NULL) {
637                 int token;
638                 if (!*p)
639                         continue;
640
641                 token = match_token(p, tokens, args);
642                 switch (token) {
643                 case Opt_barrier:
644                         nilfs_set_opt(sbi, BARRIER);
645                         break;
646                 case Opt_nobarrier:
647                         nilfs_clear_opt(sbi, BARRIER);
648                         break;
649                 case Opt_order:
650                         if (strcmp(args[0].from, "relaxed") == 0)
651                                 /* Ordered data semantics */
652                                 nilfs_clear_opt(sbi, STRICT_ORDER);
653                         else if (strcmp(args[0].from, "strict") == 0)
654                                 /* Strict in-order semantics */
655                                 nilfs_set_opt(sbi, STRICT_ORDER);
656                         else
657                                 return 0;
658                         break;
659                 case Opt_err_panic:
660                         nilfs_write_opt(sbi, ERROR_MODE, ERRORS_PANIC);
661                         break;
662                 case Opt_err_ro:
663                         nilfs_write_opt(sbi, ERROR_MODE, ERRORS_RO);
664                         break;
665                 case Opt_err_cont:
666                         nilfs_write_opt(sbi, ERROR_MODE, ERRORS_CONT);
667                         break;
668                 case Opt_snapshot:
669                         if (match_int(&args[0], &option) || option <= 0)
670                                 return 0;
671                         if (is_remount) {
672                                 if (!nilfs_test_opt(sbi, SNAPSHOT)) {
673                                         printk(KERN_ERR
674                                                "NILFS: cannot change regular "
675                                                "mount to snapshot.\n");
676                                         return 0;
677                                 } else if (option != sbi->s_snapshot_cno) {
678                                         printk(KERN_ERR
679                                                "NILFS: cannot remount to a "
680                                                "different snapshot.\n");
681                                         return 0;
682                                 }
683                                 break;
684                         }
685                         if (!(sb->s_flags & MS_RDONLY)) {
686                                 printk(KERN_ERR "NILFS: cannot mount snapshot "
687                                        "read/write.  A read-only option is "
688                                        "required.\n");
689                                 return 0;
690                         }
691                         sbi->s_snapshot_cno = option;
692                         nilfs_set_opt(sbi, SNAPSHOT);
693                         break;
694                 case Opt_norecovery:
695                         nilfs_set_opt(sbi, NORECOVERY);
696                         break;
697                 case Opt_discard:
698                         nilfs_set_opt(sbi, DISCARD);
699                         break;
700                 case Opt_nodiscard:
701                         nilfs_clear_opt(sbi, DISCARD);
702                         break;
703                 default:
704                         printk(KERN_ERR
705                                "NILFS: Unrecognized mount option \"%s\"\n", p);
706                         return 0;
707                 }
708         }
709         return 1;
710 }
711
712 static inline void
713 nilfs_set_default_options(struct nilfs_sb_info *sbi,
714                           struct nilfs_super_block *sbp)
715 {
716         sbi->s_mount_opt =
717                 NILFS_MOUNT_ERRORS_RO | NILFS_MOUNT_BARRIER;
718 }
719
720 static int nilfs_setup_super(struct nilfs_sb_info *sbi)
721 {
722         struct the_nilfs *nilfs = sbi->s_nilfs;
723         struct nilfs_super_block **sbp;
724         int max_mnt_count;
725         int mnt_count;
726
727         /* nilfs->ns_sem must be locked by the caller. */
728         sbp = nilfs_prepare_super(sbi, 0);
729         if (!sbp)
730                 return -EIO;
731
732         max_mnt_count = le16_to_cpu(sbp[0]->s_max_mnt_count);
733         mnt_count = le16_to_cpu(sbp[0]->s_mnt_count);
734
735         if (nilfs->ns_mount_state & NILFS_ERROR_FS) {
736                 printk(KERN_WARNING
737                        "NILFS warning: mounting fs with errors\n");
738 #if 0
739         } else if (max_mnt_count >= 0 && mnt_count >= max_mnt_count) {
740                 printk(KERN_WARNING
741                        "NILFS warning: maximal mount count reached\n");
742 #endif
743         }
744         if (!max_mnt_count)
745                 sbp[0]->s_max_mnt_count = cpu_to_le16(NILFS_DFL_MAX_MNT_COUNT);
746
747         sbp[0]->s_mnt_count = cpu_to_le16(mnt_count + 1);
748         sbp[0]->s_state =
749                 cpu_to_le16(le16_to_cpu(sbp[0]->s_state) & ~NILFS_VALID_FS);
750         sbp[0]->s_mtime = cpu_to_le64(get_seconds());
751         /* synchronize sbp[1] with sbp[0] */
752         memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
753         return nilfs_commit_super(sbi, NILFS_SB_COMMIT_ALL);
754 }
755
756 struct nilfs_super_block *nilfs_read_super_block(struct super_block *sb,
757                                                  u64 pos, int blocksize,
758                                                  struct buffer_head **pbh)
759 {
760         unsigned long long sb_index = pos;
761         unsigned long offset;
762
763         offset = do_div(sb_index, blocksize);
764         *pbh = sb_bread(sb, sb_index);
765         if (!*pbh)
766                 return NULL;
767         return (struct nilfs_super_block *)((char *)(*pbh)->b_data + offset);
768 }
769
770 int nilfs_store_magic_and_option(struct super_block *sb,
771                                  struct nilfs_super_block *sbp,
772                                  char *data)
773 {
774         struct nilfs_sb_info *sbi = NILFS_SB(sb);
775
776         sb->s_magic = le16_to_cpu(sbp->s_magic);
777
778         /* FS independent flags */
779 #ifdef NILFS_ATIME_DISABLE
780         sb->s_flags |= MS_NOATIME;
781 #endif
782
783         nilfs_set_default_options(sbi, sbp);
784
785         sbi->s_resuid = le16_to_cpu(sbp->s_def_resuid);
786         sbi->s_resgid = le16_to_cpu(sbp->s_def_resgid);
787         sbi->s_interval = le32_to_cpu(sbp->s_c_interval);
788         sbi->s_watermark = le32_to_cpu(sbp->s_c_block_max);
789
790         return !parse_options(data, sb, 0) ? -EINVAL : 0 ;
791 }
792
793 int nilfs_check_feature_compatibility(struct super_block *sb,
794                                       struct nilfs_super_block *sbp)
795 {
796         __u64 features;
797
798         features = le64_to_cpu(sbp->s_feature_incompat) &
799                 ~NILFS_FEATURE_INCOMPAT_SUPP;
800         if (features) {
801                 printk(KERN_ERR "NILFS: couldn't mount because of unsupported "
802                        "optional features (%llx)\n",
803                        (unsigned long long)features);
804                 return -EINVAL;
805         }
806         features = le64_to_cpu(sbp->s_feature_compat_ro) &
807                 ~NILFS_FEATURE_COMPAT_RO_SUPP;
808         if (!(sb->s_flags & MS_RDONLY) && features) {
809                 printk(KERN_ERR "NILFS: couldn't mount RDWR because of "
810                        "unsupported optional features (%llx)\n",
811                        (unsigned long long)features);
812                 return -EINVAL;
813         }
814         return 0;
815 }
816
817 /**
818  * nilfs_fill_super() - initialize a super block instance
819  * @sb: super_block
820  * @data: mount options
821  * @silent: silent mode flag
822  * @nilfs: the_nilfs struct
823  *
824  * This function is called exclusively by nilfs->ns_mount_mutex.
825  * So, the recovery process is protected from other simultaneous mounts.
826  */
827 static int
828 nilfs_fill_super(struct super_block *sb, void *data, int silent,
829                  struct the_nilfs *nilfs)
830 {
831         struct nilfs_sb_info *sbi;
832         struct inode *root;
833         __u64 cno;
834         int err;
835
836         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
837         if (!sbi)
838                 return -ENOMEM;
839
840         sb->s_fs_info = sbi;
841
842         get_nilfs(nilfs);
843         sbi->s_nilfs = nilfs;
844         sbi->s_super = sb;
845         atomic_set(&sbi->s_count, 1);
846
847         err = init_nilfs(nilfs, sbi, (char *)data);
848         if (err)
849                 goto failed_sbi;
850
851         spin_lock_init(&sbi->s_inode_lock);
852         INIT_LIST_HEAD(&sbi->s_dirty_files);
853         INIT_LIST_HEAD(&sbi->s_list);
854
855         /*
856          * Following initialization is overlapped because
857          * nilfs_sb_info structure has been cleared at the beginning.
858          * But we reserve them to keep our interest and make ready
859          * for the future change.
860          */
861         get_random_bytes(&sbi->s_next_generation,
862                          sizeof(sbi->s_next_generation));
863         spin_lock_init(&sbi->s_next_gen_lock);
864
865         sb->s_op = &nilfs_sops;
866         sb->s_export_op = &nilfs_export_ops;
867         sb->s_root = NULL;
868         sb->s_time_gran = 1;
869         sb->s_bdi = nilfs->ns_bdi;
870
871         err = load_nilfs(nilfs, sbi);
872         if (err)
873                 goto failed_sbi;
874
875         cno = nilfs_last_cno(nilfs);
876
877         if (sb->s_flags & MS_RDONLY) {
878                 if (nilfs_test_opt(sbi, SNAPSHOT)) {
879                         down_read(&nilfs->ns_segctor_sem);
880                         err = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile,
881                                                        sbi->s_snapshot_cno);
882                         up_read(&nilfs->ns_segctor_sem);
883                         if (err < 0) {
884                                 if (err == -ENOENT)
885                                         err = -EINVAL;
886                                 goto failed_sbi;
887                         }
888                         if (!err) {
889                                 printk(KERN_ERR
890                                        "NILFS: The specified checkpoint is "
891                                        "not a snapshot "
892                                        "(checkpoint number=%llu).\n",
893                                        (unsigned long long)sbi->s_snapshot_cno);
894                                 err = -EINVAL;
895                                 goto failed_sbi;
896                         }
897                         cno = sbi->s_snapshot_cno;
898                 }
899         }
900
901         err = nilfs_attach_checkpoint(sbi, cno);
902         if (err) {
903                 printk(KERN_ERR "NILFS: error loading a checkpoint"
904                        " (checkpoint number=%llu).\n", (unsigned long long)cno);
905                 goto failed_sbi;
906         }
907
908         if (!(sb->s_flags & MS_RDONLY)) {
909                 err = nilfs_attach_segment_constructor(sbi);
910                 if (err)
911                         goto failed_checkpoint;
912         }
913
914         root = nilfs_iget(sb, NILFS_ROOT_INO);
915         if (IS_ERR(root)) {
916                 printk(KERN_ERR "NILFS: get root inode failed\n");
917                 err = PTR_ERR(root);
918                 goto failed_segctor;
919         }
920         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
921                 iput(root);
922                 printk(KERN_ERR "NILFS: corrupt root inode.\n");
923                 err = -EINVAL;
924                 goto failed_segctor;
925         }
926         sb->s_root = d_alloc_root(root);
927         if (!sb->s_root) {
928                 iput(root);
929                 printk(KERN_ERR "NILFS: get root dentry failed\n");
930                 err = -ENOMEM;
931                 goto failed_segctor;
932         }
933
934         if (!(sb->s_flags & MS_RDONLY)) {
935                 down_write(&nilfs->ns_sem);
936                 nilfs_setup_super(sbi);
937                 up_write(&nilfs->ns_sem);
938         }
939
940         down_write(&nilfs->ns_super_sem);
941         if (!nilfs_test_opt(sbi, SNAPSHOT))
942                 nilfs->ns_current = sbi;
943         up_write(&nilfs->ns_super_sem);
944
945         return 0;
946
947  failed_segctor:
948         nilfs_detach_segment_constructor(sbi);
949
950  failed_checkpoint:
951         nilfs_detach_checkpoint(sbi);
952
953  failed_sbi:
954         put_nilfs(nilfs);
955         sb->s_fs_info = NULL;
956         nilfs_put_sbinfo(sbi);
957         return err;
958 }
959
960 static int nilfs_remount(struct super_block *sb, int *flags, char *data)
961 {
962         struct nilfs_sb_info *sbi = NILFS_SB(sb);
963         struct the_nilfs *nilfs = sbi->s_nilfs;
964         unsigned long old_sb_flags;
965         struct nilfs_mount_options old_opts;
966         int was_snapshot, err;
967
968         lock_kernel();
969
970         down_write(&nilfs->ns_super_sem);
971         old_sb_flags = sb->s_flags;
972         old_opts.mount_opt = sbi->s_mount_opt;
973         old_opts.snapshot_cno = sbi->s_snapshot_cno;
974         was_snapshot = nilfs_test_opt(sbi, SNAPSHOT);
975
976         if (!parse_options(data, sb, 1)) {
977                 err = -EINVAL;
978                 goto restore_opts;
979         }
980         sb->s_flags = (sb->s_flags & ~MS_POSIXACL);
981
982         err = -EINVAL;
983         if (was_snapshot && !(*flags & MS_RDONLY)) {
984                 printk(KERN_ERR "NILFS (device %s): cannot remount snapshot "
985                        "read/write.\n", sb->s_id);
986                 goto restore_opts;
987         }
988
989         if (!nilfs_valid_fs(nilfs)) {
990                 printk(KERN_WARNING "NILFS (device %s): couldn't "
991                        "remount because the filesystem is in an "
992                        "incomplete recovery state.\n", sb->s_id);
993                 goto restore_opts;
994         }
995
996         if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
997                 goto out;
998         if (*flags & MS_RDONLY) {
999                 /* Shutting down the segment constructor */
1000                 nilfs_detach_segment_constructor(sbi);
1001                 sb->s_flags |= MS_RDONLY;
1002
1003                 /*
1004                  * Remounting a valid RW partition RDONLY, so set
1005                  * the RDONLY flag and then mark the partition as valid again.
1006                  */
1007                 down_write(&nilfs->ns_sem);
1008                 nilfs_cleanup_super(sbi);
1009                 up_write(&nilfs->ns_sem);
1010         } else {
1011                 __u64 features;
1012
1013                 /*
1014                  * Mounting a RDONLY partition read-write, so reread and
1015                  * store the current valid flag.  (It may have been changed
1016                  * by fsck since we originally mounted the partition.)
1017                  */
1018                 down_read(&nilfs->ns_sem);
1019                 features = le64_to_cpu(nilfs->ns_sbp[0]->s_feature_compat_ro) &
1020                         ~NILFS_FEATURE_COMPAT_RO_SUPP;
1021                 up_read(&nilfs->ns_sem);
1022                 if (features) {
1023                         printk(KERN_WARNING "NILFS (device %s): couldn't "
1024                                "remount RDWR because of unsupported optional "
1025                                "features (%llx)\n",
1026                                sb->s_id, (unsigned long long)features);
1027                         err = -EROFS;
1028                         goto restore_opts;
1029                 }
1030
1031                 sb->s_flags &= ~MS_RDONLY;
1032
1033                 err = nilfs_attach_segment_constructor(sbi);
1034                 if (err)
1035                         goto restore_opts;
1036
1037                 down_write(&nilfs->ns_sem);
1038                 nilfs_setup_super(sbi);
1039                 up_write(&nilfs->ns_sem);
1040         }
1041  out:
1042         up_write(&nilfs->ns_super_sem);
1043         unlock_kernel();
1044         return 0;
1045
1046  restore_opts:
1047         sb->s_flags = old_sb_flags;
1048         sbi->s_mount_opt = old_opts.mount_opt;
1049         sbi->s_snapshot_cno = old_opts.snapshot_cno;
1050         up_write(&nilfs->ns_super_sem);
1051         unlock_kernel();
1052         return err;
1053 }
1054
1055 struct nilfs_super_data {
1056         struct block_device *bdev;
1057         struct nilfs_sb_info *sbi;
1058         __u64 cno;
1059         int flags;
1060 };
1061
1062 /**
1063  * nilfs_identify - pre-read mount options needed to identify mount instance
1064  * @data: mount options
1065  * @sd: nilfs_super_data
1066  */
1067 static int nilfs_identify(char *data, struct nilfs_super_data *sd)
1068 {
1069         char *p, *options = data;
1070         substring_t args[MAX_OPT_ARGS];
1071         int option, token;
1072         int ret = 0;
1073
1074         do {
1075                 p = strsep(&options, ",");
1076                 if (p != NULL && *p) {
1077                         token = match_token(p, tokens, args);
1078                         if (token == Opt_snapshot) {
1079                                 if (!(sd->flags & MS_RDONLY))
1080                                         ret++;
1081                                 else {
1082                                         ret = match_int(&args[0], &option);
1083                                         if (!ret) {
1084                                                 if (option > 0)
1085                                                         sd->cno = option;
1086                                                 else
1087                                                         ret++;
1088                                         }
1089                                 }
1090                         }
1091                         if (ret)
1092                                 printk(KERN_ERR
1093                                        "NILFS: invalid mount option: %s\n", p);
1094                 }
1095                 if (!options)
1096                         break;
1097                 BUG_ON(options == data);
1098                 *(options - 1) = ',';
1099         } while (!ret);
1100         return ret;
1101 }
1102
1103 static int nilfs_set_bdev_super(struct super_block *s, void *data)
1104 {
1105         struct nilfs_super_data *sd = data;
1106
1107         s->s_bdev = sd->bdev;
1108         s->s_dev = s->s_bdev->bd_dev;
1109         return 0;
1110 }
1111
1112 static int nilfs_test_bdev_super(struct super_block *s, void *data)
1113 {
1114         struct nilfs_super_data *sd = data;
1115
1116         return sd->sbi && s->s_fs_info == (void *)sd->sbi;
1117 }
1118
1119 static int
1120 nilfs_get_sb(struct file_system_type *fs_type, int flags,
1121              const char *dev_name, void *data, struct vfsmount *mnt)
1122 {
1123         struct nilfs_super_data sd;
1124         struct super_block *s;
1125         fmode_t mode = FMODE_READ;
1126         struct the_nilfs *nilfs;
1127         int err, need_to_close = 1;
1128
1129         if (!(flags & MS_RDONLY))
1130                 mode |= FMODE_WRITE;
1131
1132         sd.bdev = open_bdev_exclusive(dev_name, mode, fs_type);
1133         if (IS_ERR(sd.bdev))
1134                 return PTR_ERR(sd.bdev);
1135
1136         /*
1137          * To get mount instance using sget() vfs-routine, NILFS needs
1138          * much more information than normal filesystems to identify mount
1139          * instance.  For snapshot mounts, not only a mount type (ro-mount
1140          * or rw-mount) but also a checkpoint number is required.
1141          */
1142         sd.cno = 0;
1143         sd.flags = flags;
1144         if (nilfs_identify((char *)data, &sd)) {
1145                 err = -EINVAL;
1146                 goto failed;
1147         }
1148
1149         nilfs = find_or_create_nilfs(sd.bdev);
1150         if (!nilfs) {
1151                 err = -ENOMEM;
1152                 goto failed;
1153         }
1154
1155         mutex_lock(&nilfs->ns_mount_mutex);
1156
1157         if (!sd.cno) {
1158                 /*
1159                  * Check if an exclusive mount exists or not.
1160                  * Snapshot mounts coexist with a current mount
1161                  * (i.e. rw-mount or ro-mount), whereas rw-mount and
1162                  * ro-mount are mutually exclusive.
1163                  */
1164                 down_read(&nilfs->ns_super_sem);
1165                 if (nilfs->ns_current &&
1166                     ((nilfs->ns_current->s_super->s_flags ^ flags)
1167                      & MS_RDONLY)) {
1168                         up_read(&nilfs->ns_super_sem);
1169                         err = -EBUSY;
1170                         goto failed_unlock;
1171                 }
1172                 up_read(&nilfs->ns_super_sem);
1173         }
1174
1175         /*
1176          * Find existing nilfs_sb_info struct
1177          */
1178         sd.sbi = nilfs_find_sbinfo(nilfs, !(flags & MS_RDONLY), sd.cno);
1179
1180         /*
1181          * Get super block instance holding the nilfs_sb_info struct.
1182          * A new instance is allocated if no existing mount is present or
1183          * existing instance has been unmounted.
1184          */
1185         s = sget(fs_type, nilfs_test_bdev_super, nilfs_set_bdev_super, &sd);
1186         if (sd.sbi)
1187                 nilfs_put_sbinfo(sd.sbi);
1188
1189         if (IS_ERR(s)) {
1190                 err = PTR_ERR(s);
1191                 goto failed_unlock;
1192         }
1193
1194         if (!s->s_root) {
1195                 char b[BDEVNAME_SIZE];
1196
1197                 /* New superblock instance created */
1198                 s->s_flags = flags;
1199                 s->s_mode = mode;
1200                 strlcpy(s->s_id, bdevname(sd.bdev, b), sizeof(s->s_id));
1201                 sb_set_blocksize(s, block_size(sd.bdev));
1202
1203                 err = nilfs_fill_super(s, data, flags & MS_SILENT ? 1 : 0,
1204                                        nilfs);
1205                 if (err)
1206                         goto cancel_new;
1207
1208                 s->s_flags |= MS_ACTIVE;
1209                 need_to_close = 0;
1210         }
1211
1212         mutex_unlock(&nilfs->ns_mount_mutex);
1213         put_nilfs(nilfs);
1214         if (need_to_close)
1215                 close_bdev_exclusive(sd.bdev, mode);
1216         simple_set_mnt(mnt, s);
1217         return 0;
1218
1219  failed_unlock:
1220         mutex_unlock(&nilfs->ns_mount_mutex);
1221         put_nilfs(nilfs);
1222  failed:
1223         close_bdev_exclusive(sd.bdev, mode);
1224
1225         return err;
1226
1227  cancel_new:
1228         /* Abandoning the newly allocated superblock */
1229         mutex_unlock(&nilfs->ns_mount_mutex);
1230         put_nilfs(nilfs);
1231         deactivate_locked_super(s);
1232         /*
1233          * deactivate_locked_super() invokes close_bdev_exclusive().
1234          * We must finish all post-cleaning before this call;
1235          * put_nilfs() needs the block device.
1236          */
1237         return err;
1238 }
1239
1240 struct file_system_type nilfs_fs_type = {
1241         .owner    = THIS_MODULE,
1242         .name     = "nilfs2",
1243         .get_sb   = nilfs_get_sb,
1244         .kill_sb  = kill_block_super,
1245         .fs_flags = FS_REQUIRES_DEV,
1246 };
1247
1248 static void nilfs_inode_init_once(void *obj)
1249 {
1250         struct nilfs_inode_info *ii = obj;
1251
1252         INIT_LIST_HEAD(&ii->i_dirty);
1253 #ifdef CONFIG_NILFS_XATTR
1254         init_rwsem(&ii->xattr_sem);
1255 #endif
1256         nilfs_btnode_cache_init_once(&ii->i_btnode_cache);
1257         ii->i_bmap = &ii->i_bmap_data;
1258         inode_init_once(&ii->vfs_inode);
1259 }
1260
1261 static void nilfs_segbuf_init_once(void *obj)
1262 {
1263         memset(obj, 0, sizeof(struct nilfs_segment_buffer));
1264 }
1265
1266 static void nilfs_destroy_cachep(void)
1267 {
1268         if (nilfs_inode_cachep)
1269                 kmem_cache_destroy(nilfs_inode_cachep);
1270         if (nilfs_transaction_cachep)
1271                 kmem_cache_destroy(nilfs_transaction_cachep);
1272         if (nilfs_segbuf_cachep)
1273                 kmem_cache_destroy(nilfs_segbuf_cachep);
1274         if (nilfs_btree_path_cache)
1275                 kmem_cache_destroy(nilfs_btree_path_cache);
1276 }
1277
1278 static int __init nilfs_init_cachep(void)
1279 {
1280         nilfs_inode_cachep = kmem_cache_create("nilfs2_inode_cache",
1281                         sizeof(struct nilfs_inode_info), 0,
1282                         SLAB_RECLAIM_ACCOUNT, nilfs_inode_init_once);
1283         if (!nilfs_inode_cachep)
1284                 goto fail;
1285
1286         nilfs_transaction_cachep = kmem_cache_create("nilfs2_transaction_cache",
1287                         sizeof(struct nilfs_transaction_info), 0,
1288                         SLAB_RECLAIM_ACCOUNT, NULL);
1289         if (!nilfs_transaction_cachep)
1290                 goto fail;
1291
1292         nilfs_segbuf_cachep = kmem_cache_create("nilfs2_segbuf_cache",
1293                         sizeof(struct nilfs_segment_buffer), 0,
1294                         SLAB_RECLAIM_ACCOUNT, nilfs_segbuf_init_once);
1295         if (!nilfs_segbuf_cachep)
1296                 goto fail;
1297
1298         nilfs_btree_path_cache = kmem_cache_create("nilfs2_btree_path_cache",
1299                         sizeof(struct nilfs_btree_path) * NILFS_BTREE_LEVEL_MAX,
1300                         0, 0, NULL);
1301         if (!nilfs_btree_path_cache)
1302                 goto fail;
1303
1304         return 0;
1305
1306 fail:
1307         nilfs_destroy_cachep();
1308         return -ENOMEM;
1309 }
1310
1311 static int __init init_nilfs_fs(void)
1312 {
1313         int err;
1314
1315         err = nilfs_init_cachep();
1316         if (err)
1317                 goto fail;
1318
1319         err = register_filesystem(&nilfs_fs_type);
1320         if (err)
1321                 goto free_cachep;
1322
1323         printk(KERN_INFO "NILFS version 2 loaded\n");
1324         return 0;
1325
1326 free_cachep:
1327         nilfs_destroy_cachep();
1328 fail:
1329         return err;
1330 }
1331
1332 static void __exit exit_nilfs_fs(void)
1333 {
1334         nilfs_destroy_cachep();
1335         unregister_filesystem(&nilfs_fs_type);
1336 }
1337
1338 module_init(init_nilfs_fs)
1339 module_exit(exit_nilfs_fs)