nilfs2: set pointer to root object in inodes
[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/vfs.h>
49 #include <linux/writeback.h>
50 #include <linux/kobject.h>
51 #include <linux/exportfs.h>
52 #include <linux/seq_file.h>
53 #include <linux/mount.h>
54 #include "nilfs.h"
55 #include "mdt.h"
56 #include "alloc.h"
57 #include "btree.h"
58 #include "btnode.h"
59 #include "page.h"
60 #include "cpfile.h"
61 #include "ifile.h"
62 #include "dat.h"
63 #include "segment.h"
64 #include "segbuf.h"
65
66 MODULE_AUTHOR("NTT Corp.");
67 MODULE_DESCRIPTION("A New Implementation of the Log-structured Filesystem "
68                    "(NILFS)");
69 MODULE_LICENSE("GPL");
70
71 struct kmem_cache *nilfs_inode_cachep;
72 struct kmem_cache *nilfs_transaction_cachep;
73 struct kmem_cache *nilfs_segbuf_cachep;
74 struct kmem_cache *nilfs_btree_path_cache;
75
76 static int nilfs_remount(struct super_block *sb, int *flags, char *data);
77
78 static void nilfs_set_error(struct nilfs_sb_info *sbi)
79 {
80         struct the_nilfs *nilfs = sbi->s_nilfs;
81         struct nilfs_super_block **sbp;
82
83         down_write(&nilfs->ns_sem);
84         if (!(nilfs->ns_mount_state & NILFS_ERROR_FS)) {
85                 nilfs->ns_mount_state |= NILFS_ERROR_FS;
86                 sbp = nilfs_prepare_super(sbi, 0);
87                 if (likely(sbp)) {
88                         sbp[0]->s_state |= cpu_to_le16(NILFS_ERROR_FS);
89                         if (sbp[1])
90                                 sbp[1]->s_state |= cpu_to_le16(NILFS_ERROR_FS);
91                         nilfs_commit_super(sbi, NILFS_SB_COMMIT_ALL);
92                 }
93         }
94         up_write(&nilfs->ns_sem);
95 }
96
97 /**
98  * nilfs_error() - report failure condition on a filesystem
99  *
100  * nilfs_error() sets an ERROR_FS flag on the superblock as well as
101  * reporting an error message.  It should be called when NILFS detects
102  * incoherences or defects of meta data on disk.  As for sustainable
103  * errors such as a single-shot I/O error, nilfs_warning() or the printk()
104  * function should be used instead.
105  *
106  * The segment constructor must not call this function because it can
107  * kill itself.
108  */
109 void nilfs_error(struct super_block *sb, const char *function,
110                  const char *fmt, ...)
111 {
112         struct nilfs_sb_info *sbi = NILFS_SB(sb);
113         va_list args;
114
115         va_start(args, fmt);
116         printk(KERN_CRIT "NILFS error (device %s): %s: ", sb->s_id, function);
117         vprintk(fmt, args);
118         printk("\n");
119         va_end(args);
120
121         if (!(sb->s_flags & MS_RDONLY)) {
122                 nilfs_set_error(sbi);
123
124                 if (nilfs_test_opt(sbi, ERRORS_RO)) {
125                         printk(KERN_CRIT "Remounting filesystem read-only\n");
126                         sb->s_flags |= MS_RDONLY;
127                 }
128         }
129
130         if (nilfs_test_opt(sbi, ERRORS_PANIC))
131                 panic("NILFS (device %s): panic forced after error\n",
132                       sb->s_id);
133 }
134
135 void nilfs_warning(struct super_block *sb, const char *function,
136                    const char *fmt, ...)
137 {
138         va_list args;
139
140         va_start(args, fmt);
141         printk(KERN_WARNING "NILFS warning (device %s): %s: ",
142                sb->s_id, function);
143         vprintk(fmt, args);
144         printk("\n");
145         va_end(args);
146 }
147
148
149 struct inode *nilfs_alloc_inode_common(struct the_nilfs *nilfs)
150 {
151         struct nilfs_inode_info *ii;
152
153         ii = kmem_cache_alloc(nilfs_inode_cachep, GFP_NOFS);
154         if (!ii)
155                 return NULL;
156         ii->i_bh = NULL;
157         ii->i_state = 0;
158         ii->i_cno = 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         struct nilfs_mdt_info *mdi = NILFS_MDT(inode);
172
173         if (mdi) {
174                 kfree(mdi->mi_bgl); /* kfree(NULL) is safe */
175                 kfree(mdi);
176         }
177         kmem_cache_free(nilfs_inode_cachep, NILFS_I(inode));
178 }
179
180 static int nilfs_sync_super(struct nilfs_sb_info *sbi, int flag)
181 {
182         struct the_nilfs *nilfs = sbi->s_nilfs;
183         int err;
184
185  retry:
186         set_buffer_dirty(nilfs->ns_sbh[0]);
187
188         if (nilfs_test_opt(sbi, BARRIER)) {
189                 err = __sync_dirty_buffer(nilfs->ns_sbh[0],
190                                           WRITE_SYNC | WRITE_BARRIER);
191                 if (err == -EOPNOTSUPP) {
192                         nilfs_warning(sbi->s_super, __func__,
193                                       "barrier-based sync failed. "
194                                       "disabling barriers\n");
195                         nilfs_clear_opt(sbi, BARRIER);
196                         goto retry;
197                 }
198         } else {
199                 err = sync_dirty_buffer(nilfs->ns_sbh[0]);
200         }
201
202         if (unlikely(err)) {
203                 printk(KERN_ERR
204                        "NILFS: unable to write superblock (err=%d)\n", err);
205                 if (err == -EIO && nilfs->ns_sbh[1]) {
206                         /*
207                          * sbp[0] points to newer log than sbp[1],
208                          * so copy sbp[0] to sbp[1] to take over sbp[0].
209                          */
210                         memcpy(nilfs->ns_sbp[1], nilfs->ns_sbp[0],
211                                nilfs->ns_sbsize);
212                         nilfs_fall_back_super_block(nilfs);
213                         goto retry;
214                 }
215         } else {
216                 struct nilfs_super_block *sbp = nilfs->ns_sbp[0];
217
218                 nilfs->ns_sbwcount++;
219
220                 /*
221                  * The latest segment becomes trailable from the position
222                  * written in superblock.
223                  */
224                 clear_nilfs_discontinued(nilfs);
225
226                 /* update GC protection for recent segments */
227                 if (nilfs->ns_sbh[1]) {
228                         if (flag == NILFS_SB_COMMIT_ALL) {
229                                 set_buffer_dirty(nilfs->ns_sbh[1]);
230                                 if (sync_dirty_buffer(nilfs->ns_sbh[1]) < 0)
231                                         goto out;
232                         }
233                         if (le64_to_cpu(nilfs->ns_sbp[1]->s_last_cno) <
234                             le64_to_cpu(nilfs->ns_sbp[0]->s_last_cno))
235                                 sbp = nilfs->ns_sbp[1];
236                 }
237
238                 spin_lock(&nilfs->ns_last_segment_lock);
239                 nilfs->ns_prot_seq = le64_to_cpu(sbp->s_last_seq);
240                 spin_unlock(&nilfs->ns_last_segment_lock);
241         }
242  out:
243         return err;
244 }
245
246 void nilfs_set_log_cursor(struct nilfs_super_block *sbp,
247                           struct the_nilfs *nilfs)
248 {
249         sector_t nfreeblocks;
250
251         /* nilfs->ns_sem must be locked by the caller. */
252         nilfs_count_free_blocks(nilfs, &nfreeblocks);
253         sbp->s_free_blocks_count = cpu_to_le64(nfreeblocks);
254
255         spin_lock(&nilfs->ns_last_segment_lock);
256         sbp->s_last_seq = cpu_to_le64(nilfs->ns_last_seq);
257         sbp->s_last_pseg = cpu_to_le64(nilfs->ns_last_pseg);
258         sbp->s_last_cno = cpu_to_le64(nilfs->ns_last_cno);
259         spin_unlock(&nilfs->ns_last_segment_lock);
260 }
261
262 struct nilfs_super_block **nilfs_prepare_super(struct nilfs_sb_info *sbi,
263                                                int flip)
264 {
265         struct the_nilfs *nilfs = sbi->s_nilfs;
266         struct nilfs_super_block **sbp = nilfs->ns_sbp;
267
268         /* nilfs->ns_sem must be locked by the caller. */
269         if (sbp[0]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) {
270                 if (sbp[1] &&
271                     sbp[1]->s_magic == cpu_to_le16(NILFS_SUPER_MAGIC)) {
272                         memcpy(sbp[0], sbp[1], nilfs->ns_sbsize);
273                 } else {
274                         printk(KERN_CRIT "NILFS: superblock broke on dev %s\n",
275                                sbi->s_super->s_id);
276                         return NULL;
277                 }
278         } else if (sbp[1] &&
279                    sbp[1]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) {
280                         memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
281         }
282
283         if (flip && sbp[1])
284                 nilfs_swap_super_block(nilfs);
285
286         return sbp;
287 }
288
289 int nilfs_commit_super(struct nilfs_sb_info *sbi, int flag)
290 {
291         struct the_nilfs *nilfs = sbi->s_nilfs;
292         struct nilfs_super_block **sbp = nilfs->ns_sbp;
293         time_t t;
294
295         /* nilfs->ns_sem must be locked by the caller. */
296         t = get_seconds();
297         nilfs->ns_sbwtime = t;
298         sbp[0]->s_wtime = cpu_to_le64(t);
299         sbp[0]->s_sum = 0;
300         sbp[0]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed,
301                                              (unsigned char *)sbp[0],
302                                              nilfs->ns_sbsize));
303         if (flag == NILFS_SB_COMMIT_ALL && sbp[1]) {
304                 sbp[1]->s_wtime = sbp[0]->s_wtime;
305                 sbp[1]->s_sum = 0;
306                 sbp[1]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed,
307                                             (unsigned char *)sbp[1],
308                                             nilfs->ns_sbsize));
309         }
310         clear_nilfs_sb_dirty(nilfs);
311         return nilfs_sync_super(sbi, flag);
312 }
313
314 /**
315  * nilfs_cleanup_super() - write filesystem state for cleanup
316  * @sbi: nilfs_sb_info to be unmounted or degraded to read-only
317  *
318  * This function restores state flags in the on-disk super block.
319  * This will set "clean" flag (i.e. NILFS_VALID_FS) unless the
320  * filesystem was not clean previously.
321  */
322 int nilfs_cleanup_super(struct nilfs_sb_info *sbi)
323 {
324         struct nilfs_super_block **sbp;
325         int flag = NILFS_SB_COMMIT;
326         int ret = -EIO;
327
328         sbp = nilfs_prepare_super(sbi, 0);
329         if (sbp) {
330                 sbp[0]->s_state = cpu_to_le16(sbi->s_nilfs->ns_mount_state);
331                 nilfs_set_log_cursor(sbp[0], sbi->s_nilfs);
332                 if (sbp[1] && sbp[0]->s_last_cno == sbp[1]->s_last_cno) {
333                         /*
334                          * make the "clean" flag also to the opposite
335                          * super block if both super blocks point to
336                          * the same checkpoint.
337                          */
338                         sbp[1]->s_state = sbp[0]->s_state;
339                         flag = NILFS_SB_COMMIT_ALL;
340                 }
341                 ret = nilfs_commit_super(sbi, flag);
342         }
343         return ret;
344 }
345
346 static void nilfs_put_super(struct super_block *sb)
347 {
348         struct nilfs_sb_info *sbi = NILFS_SB(sb);
349         struct the_nilfs *nilfs = sbi->s_nilfs;
350
351         nilfs_detach_segment_constructor(sbi);
352
353         if (!(sb->s_flags & MS_RDONLY)) {
354                 down_write(&nilfs->ns_sem);
355                 nilfs_cleanup_super(sbi);
356                 up_write(&nilfs->ns_sem);
357         }
358         down_write(&nilfs->ns_super_sem);
359         if (nilfs->ns_current == sbi)
360                 nilfs->ns_current = NULL;
361         up_write(&nilfs->ns_super_sem);
362
363         nilfs_detach_checkpoint(sbi);
364         put_nilfs(sbi->s_nilfs);
365         sbi->s_super = NULL;
366         sb->s_fs_info = NULL;
367         nilfs_put_sbinfo(sbi);
368 }
369
370 static int nilfs_sync_fs(struct super_block *sb, int wait)
371 {
372         struct nilfs_sb_info *sbi = NILFS_SB(sb);
373         struct the_nilfs *nilfs = sbi->s_nilfs;
374         struct nilfs_super_block **sbp;
375         int err = 0;
376
377         /* This function is called when super block should be written back */
378         if (wait)
379                 err = nilfs_construct_segment(sb);
380
381         down_write(&nilfs->ns_sem);
382         if (nilfs_sb_dirty(nilfs)) {
383                 sbp = nilfs_prepare_super(sbi, nilfs_sb_will_flip(nilfs));
384                 if (likely(sbp)) {
385                         nilfs_set_log_cursor(sbp[0], nilfs);
386                         nilfs_commit_super(sbi, NILFS_SB_COMMIT);
387                 }
388         }
389         up_write(&nilfs->ns_sem);
390
391         return err;
392 }
393
394 int nilfs_attach_checkpoint(struct nilfs_sb_info *sbi, __u64 cno, int curr_mnt,
395                             struct nilfs_root **rootp)
396 {
397         struct the_nilfs *nilfs = sbi->s_nilfs;
398         struct nilfs_root *root;
399         struct nilfs_checkpoint *raw_cp;
400         struct buffer_head *bh_cp;
401         int err = -ENOMEM;
402
403         root = nilfs_find_or_create_root(
404                 nilfs, curr_mnt ? NILFS_CPTREE_CURRENT_CNO : cno);
405         if (!root)
406                 return err;
407
408         down_write(&nilfs->ns_super_sem);
409         list_add(&sbi->s_list, &nilfs->ns_supers);
410         up_write(&nilfs->ns_super_sem);
411
412         sbi->s_ifile = nilfs_ifile_new(sbi, nilfs->ns_inode_size);
413         if (!sbi->s_ifile)
414                 goto delist;
415
416         down_read(&nilfs->ns_segctor_sem);
417         err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, cno, 0, &raw_cp,
418                                           &bh_cp);
419         up_read(&nilfs->ns_segctor_sem);
420         if (unlikely(err)) {
421                 if (err == -ENOENT || err == -EINVAL) {
422                         printk(KERN_ERR
423                                "NILFS: Invalid checkpoint "
424                                "(checkpoint number=%llu)\n",
425                                (unsigned long long)cno);
426                         err = -EINVAL;
427                 }
428                 goto failed;
429         }
430         err = nilfs_read_inode_common(sbi->s_ifile, &raw_cp->cp_ifile_inode);
431         if (unlikely(err))
432                 goto failed_bh;
433         atomic_set(&sbi->s_inodes_count, le64_to_cpu(raw_cp->cp_inodes_count));
434         atomic_set(&sbi->s_blocks_count, le64_to_cpu(raw_cp->cp_blocks_count));
435
436         nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp);
437
438         *rootp = root;
439         return 0;
440
441  failed_bh:
442         nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp);
443  failed:
444         nilfs_mdt_destroy(sbi->s_ifile);
445         sbi->s_ifile = NULL;
446
447  delist:
448         down_write(&nilfs->ns_super_sem);
449         list_del_init(&sbi->s_list);
450         up_write(&nilfs->ns_super_sem);
451         nilfs_put_root(root);
452
453         return err;
454 }
455
456 void nilfs_detach_checkpoint(struct nilfs_sb_info *sbi)
457 {
458         struct the_nilfs *nilfs = sbi->s_nilfs;
459
460         nilfs_mdt_destroy(sbi->s_ifile);
461         sbi->s_ifile = NULL;
462         down_write(&nilfs->ns_super_sem);
463         list_del_init(&sbi->s_list);
464         up_write(&nilfs->ns_super_sem);
465 }
466
467 static int nilfs_statfs(struct dentry *dentry, struct kstatfs *buf)
468 {
469         struct super_block *sb = dentry->d_sb;
470         struct nilfs_sb_info *sbi = NILFS_SB(sb);
471         struct the_nilfs *nilfs = sbi->s_nilfs;
472         u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
473         unsigned long long blocks;
474         unsigned long overhead;
475         unsigned long nrsvblocks;
476         sector_t nfreeblocks;
477         int err;
478
479         /*
480          * Compute all of the segment blocks
481          *
482          * The blocks before first segment and after last segment
483          * are excluded.
484          */
485         blocks = nilfs->ns_blocks_per_segment * nilfs->ns_nsegments
486                 - nilfs->ns_first_data_block;
487         nrsvblocks = nilfs->ns_nrsvsegs * nilfs->ns_blocks_per_segment;
488
489         /*
490          * Compute the overhead
491          *
492          * When distributing meta data blocks outside segment structure,
493          * We must count them as the overhead.
494          */
495         overhead = 0;
496
497         err = nilfs_count_free_blocks(nilfs, &nfreeblocks);
498         if (unlikely(err))
499                 return err;
500
501         buf->f_type = NILFS_SUPER_MAGIC;
502         buf->f_bsize = sb->s_blocksize;
503         buf->f_blocks = blocks - overhead;
504         buf->f_bfree = nfreeblocks;
505         buf->f_bavail = (buf->f_bfree >= nrsvblocks) ?
506                 (buf->f_bfree - nrsvblocks) : 0;
507         buf->f_files = atomic_read(&sbi->s_inodes_count);
508         buf->f_ffree = 0; /* nilfs_count_free_inodes(sb); */
509         buf->f_namelen = NILFS_NAME_LEN;
510         buf->f_fsid.val[0] = (u32)id;
511         buf->f_fsid.val[1] = (u32)(id >> 32);
512
513         return 0;
514 }
515
516 static int nilfs_show_options(struct seq_file *seq, struct vfsmount *vfs)
517 {
518         struct super_block *sb = vfs->mnt_sb;
519         struct nilfs_sb_info *sbi = NILFS_SB(sb);
520
521         if (!nilfs_test_opt(sbi, BARRIER))
522                 seq_puts(seq, ",nobarrier");
523         if (nilfs_test_opt(sbi, SNAPSHOT))
524                 seq_printf(seq, ",cp=%llu",
525                            (unsigned long long int)sbi->s_snapshot_cno);
526         if (nilfs_test_opt(sbi, ERRORS_PANIC))
527                 seq_puts(seq, ",errors=panic");
528         if (nilfs_test_opt(sbi, ERRORS_CONT))
529                 seq_puts(seq, ",errors=continue");
530         if (nilfs_test_opt(sbi, STRICT_ORDER))
531                 seq_puts(seq, ",order=strict");
532         if (nilfs_test_opt(sbi, NORECOVERY))
533                 seq_puts(seq, ",norecovery");
534         if (nilfs_test_opt(sbi, DISCARD))
535                 seq_puts(seq, ",discard");
536
537         return 0;
538 }
539
540 static const struct super_operations nilfs_sops = {
541         .alloc_inode    = nilfs_alloc_inode,
542         .destroy_inode  = nilfs_destroy_inode,
543         .dirty_inode    = nilfs_dirty_inode,
544         /* .write_inode    = nilfs_write_inode, */
545         /* .put_inode      = nilfs_put_inode, */
546         /* .drop_inode    = nilfs_drop_inode, */
547         .evict_inode    = nilfs_evict_inode,
548         .put_super      = nilfs_put_super,
549         /* .write_super    = nilfs_write_super, */
550         .sync_fs        = nilfs_sync_fs,
551         /* .write_super_lockfs */
552         /* .unlockfs */
553         .statfs         = nilfs_statfs,
554         .remount_fs     = nilfs_remount,
555         /* .umount_begin */
556         .show_options = nilfs_show_options
557 };
558
559 static struct inode *
560 nilfs_nfs_get_inode(struct super_block *sb, u64 ino, u32 generation)
561 {
562         struct inode *inode;
563         struct nilfs_root *root;
564
565         if (ino < NILFS_FIRST_INO(sb) && ino != NILFS_ROOT_INO &&
566             ino != NILFS_SKETCH_INO)
567                 return ERR_PTR(-ESTALE);
568
569         root = nilfs_lookup_root(NILFS_SB(sb)->s_nilfs,
570                                  NILFS_CPTREE_CURRENT_CNO);
571         if (!root)
572                 return ERR_PTR(-ESTALE);
573
574         /* new file handle type is required to export snapshots */
575         inode = nilfs_iget(sb, root, ino);
576         nilfs_put_root(root);
577         if (IS_ERR(inode))
578                 return ERR_CAST(inode);
579         if (generation && inode->i_generation != generation) {
580                 iput(inode);
581                 return ERR_PTR(-ESTALE);
582         }
583
584         return inode;
585 }
586
587 static struct dentry *
588 nilfs_fh_to_dentry(struct super_block *sb, struct fid *fid, int fh_len,
589                    int fh_type)
590 {
591         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
592                                     nilfs_nfs_get_inode);
593 }
594
595 static struct dentry *
596 nilfs_fh_to_parent(struct super_block *sb, struct fid *fid, int fh_len,
597                    int fh_type)
598 {
599         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
600                                     nilfs_nfs_get_inode);
601 }
602
603 static const struct export_operations nilfs_export_ops = {
604         .fh_to_dentry = nilfs_fh_to_dentry,
605         .fh_to_parent = nilfs_fh_to_parent,
606         .get_parent = nilfs_get_parent,
607 };
608
609 enum {
610         Opt_err_cont, Opt_err_panic, Opt_err_ro,
611         Opt_barrier, Opt_nobarrier, Opt_snapshot, Opt_order, Opt_norecovery,
612         Opt_discard, Opt_nodiscard, Opt_err,
613 };
614
615 static match_table_t tokens = {
616         {Opt_err_cont, "errors=continue"},
617         {Opt_err_panic, "errors=panic"},
618         {Opt_err_ro, "errors=remount-ro"},
619         {Opt_barrier, "barrier"},
620         {Opt_nobarrier, "nobarrier"},
621         {Opt_snapshot, "cp=%u"},
622         {Opt_order, "order=%s"},
623         {Opt_norecovery, "norecovery"},
624         {Opt_discard, "discard"},
625         {Opt_nodiscard, "nodiscard"},
626         {Opt_err, NULL}
627 };
628
629 static int parse_options(char *options, struct super_block *sb, int is_remount)
630 {
631         struct nilfs_sb_info *sbi = NILFS_SB(sb);
632         char *p;
633         substring_t args[MAX_OPT_ARGS];
634         int option;
635
636         if (!options)
637                 return 1;
638
639         while ((p = strsep(&options, ",")) != NULL) {
640                 int token;
641                 if (!*p)
642                         continue;
643
644                 token = match_token(p, tokens, args);
645                 switch (token) {
646                 case Opt_barrier:
647                         nilfs_set_opt(sbi, BARRIER);
648                         break;
649                 case Opt_nobarrier:
650                         nilfs_clear_opt(sbi, BARRIER);
651                         break;
652                 case Opt_order:
653                         if (strcmp(args[0].from, "relaxed") == 0)
654                                 /* Ordered data semantics */
655                                 nilfs_clear_opt(sbi, STRICT_ORDER);
656                         else if (strcmp(args[0].from, "strict") == 0)
657                                 /* Strict in-order semantics */
658                                 nilfs_set_opt(sbi, STRICT_ORDER);
659                         else
660                                 return 0;
661                         break;
662                 case Opt_err_panic:
663                         nilfs_write_opt(sbi, ERROR_MODE, ERRORS_PANIC);
664                         break;
665                 case Opt_err_ro:
666                         nilfs_write_opt(sbi, ERROR_MODE, ERRORS_RO);
667                         break;
668                 case Opt_err_cont:
669                         nilfs_write_opt(sbi, ERROR_MODE, ERRORS_CONT);
670                         break;
671                 case Opt_snapshot:
672                         if (match_int(&args[0], &option) || option <= 0)
673                                 return 0;
674                         if (is_remount) {
675                                 if (!nilfs_test_opt(sbi, SNAPSHOT)) {
676                                         printk(KERN_ERR
677                                                "NILFS: cannot change regular "
678                                                "mount to snapshot.\n");
679                                         return 0;
680                                 } else if (option != sbi->s_snapshot_cno) {
681                                         printk(KERN_ERR
682                                                "NILFS: cannot remount to a "
683                                                "different snapshot.\n");
684                                         return 0;
685                                 }
686                                 break;
687                         }
688                         if (!(sb->s_flags & MS_RDONLY)) {
689                                 printk(KERN_ERR "NILFS: cannot mount snapshot "
690                                        "read/write.  A read-only option is "
691                                        "required.\n");
692                                 return 0;
693                         }
694                         sbi->s_snapshot_cno = option;
695                         nilfs_set_opt(sbi, SNAPSHOT);
696                         break;
697                 case Opt_norecovery:
698                         nilfs_set_opt(sbi, NORECOVERY);
699                         break;
700                 case Opt_discard:
701                         nilfs_set_opt(sbi, DISCARD);
702                         break;
703                 case Opt_nodiscard:
704                         nilfs_clear_opt(sbi, DISCARD);
705                         break;
706                 default:
707                         printk(KERN_ERR
708                                "NILFS: Unrecognized mount option \"%s\"\n", p);
709                         return 0;
710                 }
711         }
712         return 1;
713 }
714
715 static inline void
716 nilfs_set_default_options(struct nilfs_sb_info *sbi,
717                           struct nilfs_super_block *sbp)
718 {
719         sbi->s_mount_opt =
720                 NILFS_MOUNT_ERRORS_RO | NILFS_MOUNT_BARRIER;
721 }
722
723 static int nilfs_setup_super(struct nilfs_sb_info *sbi)
724 {
725         struct the_nilfs *nilfs = sbi->s_nilfs;
726         struct nilfs_super_block **sbp;
727         int max_mnt_count;
728         int mnt_count;
729
730         /* nilfs->ns_sem must be locked by the caller. */
731         sbp = nilfs_prepare_super(sbi, 0);
732         if (!sbp)
733                 return -EIO;
734
735         max_mnt_count = le16_to_cpu(sbp[0]->s_max_mnt_count);
736         mnt_count = le16_to_cpu(sbp[0]->s_mnt_count);
737
738         if (nilfs->ns_mount_state & NILFS_ERROR_FS) {
739                 printk(KERN_WARNING
740                        "NILFS warning: mounting fs with errors\n");
741 #if 0
742         } else if (max_mnt_count >= 0 && mnt_count >= max_mnt_count) {
743                 printk(KERN_WARNING
744                        "NILFS warning: maximal mount count reached\n");
745 #endif
746         }
747         if (!max_mnt_count)
748                 sbp[0]->s_max_mnt_count = cpu_to_le16(NILFS_DFL_MAX_MNT_COUNT);
749
750         sbp[0]->s_mnt_count = cpu_to_le16(mnt_count + 1);
751         sbp[0]->s_state =
752                 cpu_to_le16(le16_to_cpu(sbp[0]->s_state) & ~NILFS_VALID_FS);
753         sbp[0]->s_mtime = cpu_to_le64(get_seconds());
754         /* synchronize sbp[1] with sbp[0] */
755         memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
756         return nilfs_commit_super(sbi, NILFS_SB_COMMIT_ALL);
757 }
758
759 struct nilfs_super_block *nilfs_read_super_block(struct super_block *sb,
760                                                  u64 pos, int blocksize,
761                                                  struct buffer_head **pbh)
762 {
763         unsigned long long sb_index = pos;
764         unsigned long offset;
765
766         offset = do_div(sb_index, blocksize);
767         *pbh = sb_bread(sb, sb_index);
768         if (!*pbh)
769                 return NULL;
770         return (struct nilfs_super_block *)((char *)(*pbh)->b_data + offset);
771 }
772
773 int nilfs_store_magic_and_option(struct super_block *sb,
774                                  struct nilfs_super_block *sbp,
775                                  char *data)
776 {
777         struct nilfs_sb_info *sbi = NILFS_SB(sb);
778
779         sb->s_magic = le16_to_cpu(sbp->s_magic);
780
781         /* FS independent flags */
782 #ifdef NILFS_ATIME_DISABLE
783         sb->s_flags |= MS_NOATIME;
784 #endif
785
786         nilfs_set_default_options(sbi, sbp);
787
788         sbi->s_resuid = le16_to_cpu(sbp->s_def_resuid);
789         sbi->s_resgid = le16_to_cpu(sbp->s_def_resgid);
790         sbi->s_interval = le32_to_cpu(sbp->s_c_interval);
791         sbi->s_watermark = le32_to_cpu(sbp->s_c_block_max);
792
793         return !parse_options(data, sb, 0) ? -EINVAL : 0 ;
794 }
795
796 int nilfs_check_feature_compatibility(struct super_block *sb,
797                                       struct nilfs_super_block *sbp)
798 {
799         __u64 features;
800
801         features = le64_to_cpu(sbp->s_feature_incompat) &
802                 ~NILFS_FEATURE_INCOMPAT_SUPP;
803         if (features) {
804                 printk(KERN_ERR "NILFS: couldn't mount because of unsupported "
805                        "optional features (%llx)\n",
806                        (unsigned long long)features);
807                 return -EINVAL;
808         }
809         features = le64_to_cpu(sbp->s_feature_compat_ro) &
810                 ~NILFS_FEATURE_COMPAT_RO_SUPP;
811         if (!(sb->s_flags & MS_RDONLY) && features) {
812                 printk(KERN_ERR "NILFS: couldn't mount RDWR because of "
813                        "unsupported optional features (%llx)\n",
814                        (unsigned long long)features);
815                 return -EINVAL;
816         }
817         return 0;
818 }
819
820 /**
821  * nilfs_fill_super() - initialize a super block instance
822  * @sb: super_block
823  * @data: mount options
824  * @silent: silent mode flag
825  * @nilfs: the_nilfs struct
826  *
827  * This function is called exclusively by nilfs->ns_mount_mutex.
828  * So, the recovery process is protected from other simultaneous mounts.
829  */
830 static int
831 nilfs_fill_super(struct super_block *sb, void *data, int silent,
832                  struct the_nilfs *nilfs)
833 {
834         struct nilfs_sb_info *sbi;
835         struct nilfs_root *fsroot;
836         struct inode *root;
837         __u64 cno;
838         int err, curr_mnt;
839
840         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
841         if (!sbi)
842                 return -ENOMEM;
843
844         sb->s_fs_info = sbi;
845
846         get_nilfs(nilfs);
847         sbi->s_nilfs = nilfs;
848         sbi->s_super = sb;
849         atomic_set(&sbi->s_count, 1);
850
851         err = init_nilfs(nilfs, sbi, (char *)data);
852         if (err)
853                 goto failed_sbi;
854
855         spin_lock_init(&sbi->s_inode_lock);
856         INIT_LIST_HEAD(&sbi->s_dirty_files);
857         INIT_LIST_HEAD(&sbi->s_list);
858
859         /*
860          * Following initialization is overlapped because
861          * nilfs_sb_info structure has been cleared at the beginning.
862          * But we reserve them to keep our interest and make ready
863          * for the future change.
864          */
865         get_random_bytes(&sbi->s_next_generation,
866                          sizeof(sbi->s_next_generation));
867         spin_lock_init(&sbi->s_next_gen_lock);
868
869         sb->s_op = &nilfs_sops;
870         sb->s_export_op = &nilfs_export_ops;
871         sb->s_root = NULL;
872         sb->s_time_gran = 1;
873         sb->s_bdi = nilfs->ns_bdi;
874
875         err = load_nilfs(nilfs, sbi);
876         if (err)
877                 goto failed_sbi;
878
879         cno = nilfs_last_cno(nilfs);
880         curr_mnt = true;
881
882         if (sb->s_flags & MS_RDONLY) {
883                 if (nilfs_test_opt(sbi, SNAPSHOT)) {
884                         down_read(&nilfs->ns_segctor_sem);
885                         err = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile,
886                                                        sbi->s_snapshot_cno);
887                         up_read(&nilfs->ns_segctor_sem);
888                         if (err < 0) {
889                                 if (err == -ENOENT)
890                                         err = -EINVAL;
891                                 goto failed_sbi;
892                         }
893                         if (!err) {
894                                 printk(KERN_ERR
895                                        "NILFS: The specified checkpoint is "
896                                        "not a snapshot "
897                                        "(checkpoint number=%llu).\n",
898                                        (unsigned long long)sbi->s_snapshot_cno);
899                                 err = -EINVAL;
900                                 goto failed_sbi;
901                         }
902                         cno = sbi->s_snapshot_cno;
903                         curr_mnt = false;
904                 }
905         }
906
907         err = nilfs_attach_checkpoint(sbi, cno, curr_mnt, &fsroot);
908         if (err) {
909                 printk(KERN_ERR "NILFS: error loading a checkpoint"
910                        " (checkpoint number=%llu).\n", (unsigned long long)cno);
911                 goto failed_sbi;
912         }
913
914         if (!(sb->s_flags & MS_RDONLY)) {
915                 err = nilfs_attach_segment_constructor(sbi);
916                 if (err)
917                         goto failed_checkpoint;
918         }
919
920         root = nilfs_iget(sb, fsroot, NILFS_ROOT_INO);
921         if (IS_ERR(root)) {
922                 printk(KERN_ERR "NILFS: get root inode failed\n");
923                 err = PTR_ERR(root);
924                 goto failed_segctor;
925         }
926         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
927                 iput(root);
928                 printk(KERN_ERR "NILFS: corrupt root inode.\n");
929                 err = -EINVAL;
930                 goto failed_segctor;
931         }
932         sb->s_root = d_alloc_root(root);
933         if (!sb->s_root) {
934                 iput(root);
935                 printk(KERN_ERR "NILFS: get root dentry failed\n");
936                 err = -ENOMEM;
937                 goto failed_segctor;
938         }
939
940         nilfs_put_root(fsroot);
941
942         if (!(sb->s_flags & MS_RDONLY)) {
943                 down_write(&nilfs->ns_sem);
944                 nilfs_setup_super(sbi);
945                 up_write(&nilfs->ns_sem);
946         }
947
948         down_write(&nilfs->ns_super_sem);
949         if (!nilfs_test_opt(sbi, SNAPSHOT))
950                 nilfs->ns_current = sbi;
951         up_write(&nilfs->ns_super_sem);
952
953         return 0;
954
955  failed_segctor:
956         nilfs_detach_segment_constructor(sbi);
957
958  failed_checkpoint:
959         nilfs_detach_checkpoint(sbi);
960         nilfs_put_root(fsroot);
961
962  failed_sbi:
963         put_nilfs(nilfs);
964         sb->s_fs_info = NULL;
965         nilfs_put_sbinfo(sbi);
966         return err;
967 }
968
969 static int nilfs_remount(struct super_block *sb, int *flags, char *data)
970 {
971         struct nilfs_sb_info *sbi = NILFS_SB(sb);
972         struct the_nilfs *nilfs = sbi->s_nilfs;
973         unsigned long old_sb_flags;
974         struct nilfs_mount_options old_opts;
975         int was_snapshot, err;
976
977         down_write(&nilfs->ns_super_sem);
978         old_sb_flags = sb->s_flags;
979         old_opts.mount_opt = sbi->s_mount_opt;
980         old_opts.snapshot_cno = sbi->s_snapshot_cno;
981         was_snapshot = nilfs_test_opt(sbi, SNAPSHOT);
982
983         if (!parse_options(data, sb, 1)) {
984                 err = -EINVAL;
985                 goto restore_opts;
986         }
987         sb->s_flags = (sb->s_flags & ~MS_POSIXACL);
988
989         err = -EINVAL;
990         if (was_snapshot && !(*flags & MS_RDONLY)) {
991                 printk(KERN_ERR "NILFS (device %s): cannot remount snapshot "
992                        "read/write.\n", sb->s_id);
993                 goto restore_opts;
994         }
995
996         if (!nilfs_valid_fs(nilfs)) {
997                 printk(KERN_WARNING "NILFS (device %s): couldn't "
998                        "remount because the filesystem is in an "
999                        "incomplete recovery state.\n", sb->s_id);
1000                 goto restore_opts;
1001         }
1002
1003         if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
1004                 goto out;
1005         if (*flags & MS_RDONLY) {
1006                 /* Shutting down the segment constructor */
1007                 nilfs_detach_segment_constructor(sbi);
1008                 sb->s_flags |= MS_RDONLY;
1009
1010                 /*
1011                  * Remounting a valid RW partition RDONLY, so set
1012                  * the RDONLY flag and then mark the partition as valid again.
1013                  */
1014                 down_write(&nilfs->ns_sem);
1015                 nilfs_cleanup_super(sbi);
1016                 up_write(&nilfs->ns_sem);
1017         } else {
1018                 __u64 features;
1019
1020                 /*
1021                  * Mounting a RDONLY partition read-write, so reread and
1022                  * store the current valid flag.  (It may have been changed
1023                  * by fsck since we originally mounted the partition.)
1024                  */
1025                 down_read(&nilfs->ns_sem);
1026                 features = le64_to_cpu(nilfs->ns_sbp[0]->s_feature_compat_ro) &
1027                         ~NILFS_FEATURE_COMPAT_RO_SUPP;
1028                 up_read(&nilfs->ns_sem);
1029                 if (features) {
1030                         printk(KERN_WARNING "NILFS (device %s): couldn't "
1031                                "remount RDWR because of unsupported optional "
1032                                "features (%llx)\n",
1033                                sb->s_id, (unsigned long long)features);
1034                         err = -EROFS;
1035                         goto restore_opts;
1036                 }
1037
1038                 sb->s_flags &= ~MS_RDONLY;
1039
1040                 err = nilfs_attach_segment_constructor(sbi);
1041                 if (err)
1042                         goto restore_opts;
1043
1044                 down_write(&nilfs->ns_sem);
1045                 nilfs_setup_super(sbi);
1046                 up_write(&nilfs->ns_sem);
1047         }
1048  out:
1049         up_write(&nilfs->ns_super_sem);
1050         return 0;
1051
1052  restore_opts:
1053         sb->s_flags = old_sb_flags;
1054         sbi->s_mount_opt = old_opts.mount_opt;
1055         sbi->s_snapshot_cno = old_opts.snapshot_cno;
1056         up_write(&nilfs->ns_super_sem);
1057         return err;
1058 }
1059
1060 struct nilfs_super_data {
1061         struct block_device *bdev;
1062         struct nilfs_sb_info *sbi;
1063         __u64 cno;
1064         int flags;
1065 };
1066
1067 /**
1068  * nilfs_identify - pre-read mount options needed to identify mount instance
1069  * @data: mount options
1070  * @sd: nilfs_super_data
1071  */
1072 static int nilfs_identify(char *data, struct nilfs_super_data *sd)
1073 {
1074         char *p, *options = data;
1075         substring_t args[MAX_OPT_ARGS];
1076         int option, token;
1077         int ret = 0;
1078
1079         do {
1080                 p = strsep(&options, ",");
1081                 if (p != NULL && *p) {
1082                         token = match_token(p, tokens, args);
1083                         if (token == Opt_snapshot) {
1084                                 if (!(sd->flags & MS_RDONLY))
1085                                         ret++;
1086                                 else {
1087                                         ret = match_int(&args[0], &option);
1088                                         if (!ret) {
1089                                                 if (option > 0)
1090                                                         sd->cno = option;
1091                                                 else
1092                                                         ret++;
1093                                         }
1094                                 }
1095                         }
1096                         if (ret)
1097                                 printk(KERN_ERR
1098                                        "NILFS: invalid mount option: %s\n", p);
1099                 }
1100                 if (!options)
1101                         break;
1102                 BUG_ON(options == data);
1103                 *(options - 1) = ',';
1104         } while (!ret);
1105         return ret;
1106 }
1107
1108 static int nilfs_set_bdev_super(struct super_block *s, void *data)
1109 {
1110         struct nilfs_super_data *sd = data;
1111
1112         s->s_bdev = sd->bdev;
1113         s->s_dev = s->s_bdev->bd_dev;
1114         return 0;
1115 }
1116
1117 static int nilfs_test_bdev_super(struct super_block *s, void *data)
1118 {
1119         struct nilfs_super_data *sd = data;
1120
1121         return sd->sbi && s->s_fs_info == (void *)sd->sbi;
1122 }
1123
1124 static int
1125 nilfs_get_sb(struct file_system_type *fs_type, int flags,
1126              const char *dev_name, void *data, struct vfsmount *mnt)
1127 {
1128         struct nilfs_super_data sd;
1129         struct super_block *s;
1130         fmode_t mode = FMODE_READ;
1131         struct the_nilfs *nilfs;
1132         int err, need_to_close = 1;
1133
1134         if (!(flags & MS_RDONLY))
1135                 mode |= FMODE_WRITE;
1136
1137         sd.bdev = open_bdev_exclusive(dev_name, mode, fs_type);
1138         if (IS_ERR(sd.bdev))
1139                 return PTR_ERR(sd.bdev);
1140
1141         /*
1142          * To get mount instance using sget() vfs-routine, NILFS needs
1143          * much more information than normal filesystems to identify mount
1144          * instance.  For snapshot mounts, not only a mount type (ro-mount
1145          * or rw-mount) but also a checkpoint number is required.
1146          */
1147         sd.cno = 0;
1148         sd.flags = flags;
1149         if (nilfs_identify((char *)data, &sd)) {
1150                 err = -EINVAL;
1151                 goto failed;
1152         }
1153
1154         nilfs = find_or_create_nilfs(sd.bdev);
1155         if (!nilfs) {
1156                 err = -ENOMEM;
1157                 goto failed;
1158         }
1159
1160         mutex_lock(&nilfs->ns_mount_mutex);
1161
1162         if (!sd.cno) {
1163                 /*
1164                  * Check if an exclusive mount exists or not.
1165                  * Snapshot mounts coexist with a current mount
1166                  * (i.e. rw-mount or ro-mount), whereas rw-mount and
1167                  * ro-mount are mutually exclusive.
1168                  */
1169                 down_read(&nilfs->ns_super_sem);
1170                 if (nilfs->ns_current &&
1171                     ((nilfs->ns_current->s_super->s_flags ^ flags)
1172                      & MS_RDONLY)) {
1173                         up_read(&nilfs->ns_super_sem);
1174                         err = -EBUSY;
1175                         goto failed_unlock;
1176                 }
1177                 up_read(&nilfs->ns_super_sem);
1178         }
1179
1180         /*
1181          * Find existing nilfs_sb_info struct
1182          */
1183         sd.sbi = nilfs_find_sbinfo(nilfs, !(flags & MS_RDONLY), sd.cno);
1184
1185         /*
1186          * Get super block instance holding the nilfs_sb_info struct.
1187          * A new instance is allocated if no existing mount is present or
1188          * existing instance has been unmounted.
1189          */
1190         s = sget(fs_type, nilfs_test_bdev_super, nilfs_set_bdev_super, &sd);
1191         if (sd.sbi)
1192                 nilfs_put_sbinfo(sd.sbi);
1193
1194         if (IS_ERR(s)) {
1195                 err = PTR_ERR(s);
1196                 goto failed_unlock;
1197         }
1198
1199         if (!s->s_root) {
1200                 char b[BDEVNAME_SIZE];
1201
1202                 /* New superblock instance created */
1203                 s->s_flags = flags;
1204                 s->s_mode = mode;
1205                 strlcpy(s->s_id, bdevname(sd.bdev, b), sizeof(s->s_id));
1206                 sb_set_blocksize(s, block_size(sd.bdev));
1207
1208                 err = nilfs_fill_super(s, data, flags & MS_SILENT ? 1 : 0,
1209                                        nilfs);
1210                 if (err)
1211                         goto cancel_new;
1212
1213                 s->s_flags |= MS_ACTIVE;
1214                 need_to_close = 0;
1215         }
1216
1217         mutex_unlock(&nilfs->ns_mount_mutex);
1218         put_nilfs(nilfs);
1219         if (need_to_close)
1220                 close_bdev_exclusive(sd.bdev, mode);
1221         simple_set_mnt(mnt, s);
1222         return 0;
1223
1224  failed_unlock:
1225         mutex_unlock(&nilfs->ns_mount_mutex);
1226         put_nilfs(nilfs);
1227  failed:
1228         close_bdev_exclusive(sd.bdev, mode);
1229         return err;
1230
1231  cancel_new:
1232         /* Abandoning the newly allocated superblock */
1233         mutex_unlock(&nilfs->ns_mount_mutex);
1234         put_nilfs(nilfs);
1235         deactivate_locked_super(s);
1236         /*
1237          * deactivate_locked_super() invokes close_bdev_exclusive().
1238          * We must finish all post-cleaning before this call;
1239          * put_nilfs() needs the block device.
1240          */
1241         return err;
1242 }
1243
1244 struct file_system_type nilfs_fs_type = {
1245         .owner    = THIS_MODULE,
1246         .name     = "nilfs2",
1247         .get_sb   = nilfs_get_sb,
1248         .kill_sb  = kill_block_super,
1249         .fs_flags = FS_REQUIRES_DEV,
1250 };
1251
1252 static void nilfs_inode_init_once(void *obj)
1253 {
1254         struct nilfs_inode_info *ii = obj;
1255
1256         INIT_LIST_HEAD(&ii->i_dirty);
1257 #ifdef CONFIG_NILFS_XATTR
1258         init_rwsem(&ii->xattr_sem);
1259 #endif
1260         nilfs_btnode_cache_init_once(&ii->i_btnode_cache);
1261         ii->i_bmap = &ii->i_bmap_data;
1262         inode_init_once(&ii->vfs_inode);
1263 }
1264
1265 static void nilfs_segbuf_init_once(void *obj)
1266 {
1267         memset(obj, 0, sizeof(struct nilfs_segment_buffer));
1268 }
1269
1270 static void nilfs_destroy_cachep(void)
1271 {
1272         if (nilfs_inode_cachep)
1273                 kmem_cache_destroy(nilfs_inode_cachep);
1274         if (nilfs_transaction_cachep)
1275                 kmem_cache_destroy(nilfs_transaction_cachep);
1276         if (nilfs_segbuf_cachep)
1277                 kmem_cache_destroy(nilfs_segbuf_cachep);
1278         if (nilfs_btree_path_cache)
1279                 kmem_cache_destroy(nilfs_btree_path_cache);
1280 }
1281
1282 static int __init nilfs_init_cachep(void)
1283 {
1284         nilfs_inode_cachep = kmem_cache_create("nilfs2_inode_cache",
1285                         sizeof(struct nilfs_inode_info), 0,
1286                         SLAB_RECLAIM_ACCOUNT, nilfs_inode_init_once);
1287         if (!nilfs_inode_cachep)
1288                 goto fail;
1289
1290         nilfs_transaction_cachep = kmem_cache_create("nilfs2_transaction_cache",
1291                         sizeof(struct nilfs_transaction_info), 0,
1292                         SLAB_RECLAIM_ACCOUNT, NULL);
1293         if (!nilfs_transaction_cachep)
1294                 goto fail;
1295
1296         nilfs_segbuf_cachep = kmem_cache_create("nilfs2_segbuf_cache",
1297                         sizeof(struct nilfs_segment_buffer), 0,
1298                         SLAB_RECLAIM_ACCOUNT, nilfs_segbuf_init_once);
1299         if (!nilfs_segbuf_cachep)
1300                 goto fail;
1301
1302         nilfs_btree_path_cache = kmem_cache_create("nilfs2_btree_path_cache",
1303                         sizeof(struct nilfs_btree_path) * NILFS_BTREE_LEVEL_MAX,
1304                         0, 0, NULL);
1305         if (!nilfs_btree_path_cache)
1306                 goto fail;
1307
1308         return 0;
1309
1310 fail:
1311         nilfs_destroy_cachep();
1312         return -ENOMEM;
1313 }
1314
1315 static int __init init_nilfs_fs(void)
1316 {
1317         int err;
1318
1319         err = nilfs_init_cachep();
1320         if (err)
1321                 goto fail;
1322
1323         err = register_filesystem(&nilfs_fs_type);
1324         if (err)
1325                 goto free_cachep;
1326
1327         printk(KERN_INFO "NILFS version 2 loaded\n");
1328         return 0;
1329
1330 free_cachep:
1331         nilfs_destroy_cachep();
1332 fail:
1333         return err;
1334 }
1335
1336 static void __exit exit_nilfs_fs(void)
1337 {
1338         nilfs_destroy_cachep();
1339         unregister_filesystem(&nilfs_fs_type);
1340 }
1341
1342 module_init(init_nilfs_fs)
1343 module_exit(exit_nilfs_fs)