1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * NILFS module and super block management.
4 *
5 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
6 *
7 * Written by Ryusuke Konishi.
8 */
9 /*
10 * linux/fs/ext2/super.c
11 *
12 * Copyright (C) 1992, 1993, 1994, 1995
13 * Remy Card (card@masi.ibp.fr)
14 * Laboratoire MASI - Institut Blaise Pascal
15 * Universite Pierre et Marie Curie (Paris VI)
16 *
17 * from
18 *
19 * linux/fs/minix/inode.c
20 *
21 * Copyright (C) 1991, 1992 Linus Torvalds
22 *
23 * Big-endian to little-endian byte-swapping/bitmaps by
24 * David S. Miller (davem@caip.rutgers.edu), 1995
25 */
26
27 #include <linux/module.h>
28 #include <linux/string.h>
29 #include <linux/slab.h>
30 #include <linux/init.h>
31 #include <linux/blkdev.h>
32 #include <linux/crc32.h>
33 #include <linux/vfs.h>
34 #include <linux/writeback.h>
35 #include <linux/seq_file.h>
36 #include <linux/mount.h>
37 #include <linux/fs_context.h>
38 #include <linux/fs_parser.h>
39 #include "nilfs.h"
40 #include "export.h"
41 #include "mdt.h"
42 #include "alloc.h"
43 #include "btree.h"
44 #include "btnode.h"
45 #include "page.h"
46 #include "cpfile.h"
47 #include "sufile.h" /* nilfs_sufile_resize(), nilfs_sufile_set_alloc_range() */
48 #include "ifile.h"
49 #include "dat.h"
50 #include "segment.h"
51 #include "segbuf.h"
52
53 MODULE_AUTHOR("NTT Corp.");
54 MODULE_DESCRIPTION("A New Implementation of the Log-structured Filesystem "
55 "(NILFS)");
56 MODULE_LICENSE("GPL");
57
58 static struct kmem_cache *nilfs_inode_cachep;
59 struct kmem_cache *nilfs_transaction_cachep;
60 struct kmem_cache *nilfs_segbuf_cachep;
61 struct kmem_cache *nilfs_btree_path_cache;
62
63 static int nilfs_setup_super(struct super_block *sb, int is_mount);
64
65 void __nilfs_msg(struct super_block *sb, const char *fmt, ...)
66 {
67 struct va_format vaf;
68 va_list args;
69 int level;
70
71 va_start(args, fmt);
72
73 level = printk_get_level(fmt);
74 vaf.fmt = printk_skip_level(fmt);
75 vaf.va = &args;
76
77 if (sb)
78 printk("%c%cNILFS (%s): %pV\n",
79 KERN_SOH_ASCII, level, sb->s_id, &vaf);
80 else
81 printk("%c%cNILFS: %pV\n",
82 KERN_SOH_ASCII, level, &vaf);
83
84 va_end(args);
85 }
86
87 static void nilfs_set_error(struct super_block *sb)
88 {
89 struct the_nilfs *nilfs = sb->s_fs_info;
90 struct nilfs_super_block **sbp;
91
92 down_write(&nilfs->ns_sem);
93 if (!(nilfs->ns_mount_state & NILFS_ERROR_FS)) {
94 nilfs->ns_mount_state |= NILFS_ERROR_FS;
95 sbp = nilfs_prepare_super(sb, 0);
96 if (likely(sbp)) {
97 sbp[0]->s_state |= cpu_to_le16(NILFS_ERROR_FS);
98 if (sbp[1])
99 sbp[1]->s_state |= cpu_to_le16(NILFS_ERROR_FS);
100 nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL);
101 }
102 }
103 up_write(&nilfs->ns_sem);
104 }
105
106 /**
107 * __nilfs_error() - report failure condition on a filesystem
108 *
109 * __nilfs_error() sets an ERROR_FS flag on the superblock as well as
110 * reporting an error message. This function should be called when
111 * NILFS detects incoherences or defects of meta data on disk.
112 *
113 * This implements the body of nilfs_error() macro. Normally,
114 * nilfs_error() should be used. As for sustainable errors such as a
115 * single-shot I/O error, nilfs_err() should be used instead.
116 *
117 * Callers should not add a trailing newline since this will do it.
118 */
119 void __nilfs_error(struct super_block *sb, const char *function,
120 const char *fmt, ...)
121 {
122 struct the_nilfs *nilfs = sb->s_fs_info;
123 struct va_format vaf;
124 va_list args;
125
126 va_start(args, fmt);
127
128 vaf.fmt = fmt;
129 vaf.va = &args;
130
131 printk(KERN_CRIT "NILFS error (device %s): %s: %pV\n",
132 sb->s_id, function, &vaf);
133
134 va_end(args);
135
136 if (!sb_rdonly(sb)) {
137 nilfs_set_error(sb);
138
139 if (nilfs_test_opt(nilfs, ERRORS_RO)) {
140 printk(KERN_CRIT "Remounting filesystem read-only\n");
141 sb->s_flags |= SB_RDONLY;
142 }
143 }
144
145 if (nilfs_test_opt(nilfs, ERRORS_PANIC))
146 panic("NILFS (device %s): panic forced after error\n",
147 sb->s_id);
148 }
149
150 struct inode *nilfs_alloc_inode(struct super_block *sb)
151 {
152 struct nilfs_inode_info *ii;
153
154 ii = alloc_inode_sb(sb, nilfs_inode_cachep, GFP_NOFS);
155 if (!ii)
156 return NULL;
157 ii->i_bh = NULL;
158 ii->i_state = 0;
159 ii->i_cno = 0;
160 ii->i_assoc_inode = NULL;
161 ii->i_bmap = &ii->i_bmap_data;
162 return &ii->vfs_inode;
163 }
164
165 static void nilfs_free_inode(struct inode *inode)
166 {
167 if (nilfs_is_metadata_file_inode(inode))
168 nilfs_mdt_destroy(inode);
169
170 kmem_cache_free(nilfs_inode_cachep, NILFS_I(inode));
171 }
172
173 static int nilfs_sync_super(struct super_block *sb, int flag)
174 {
175 struct the_nilfs *nilfs = sb->s_fs_info;
176 int err;
177
178 retry:
179 set_buffer_dirty(nilfs->ns_sbh[0]);
180 if (nilfs_test_opt(nilfs, BARRIER)) {
181 err = __sync_dirty_buffer(nilfs->ns_sbh[0],
182 REQ_SYNC | REQ_PREFLUSH | REQ_FUA);
183 } else {
184 err = sync_dirty_buffer(nilfs->ns_sbh[0]);
185 }
186
187 if (unlikely(err)) {
188 nilfs_err(sb, "unable to write superblock: err=%d", err);
189 if (err == -EIO && nilfs->ns_sbh[1]) {
190 /*
191 * sbp[0] points to newer log than sbp[1],
192 * so copy sbp[0] to sbp[1] to take over sbp[0].
193 */
194 memcpy(nilfs->ns_sbp[1], nilfs->ns_sbp[0],
195 nilfs->ns_sbsize);
196 nilfs_fall_back_super_block(nilfs);
197 goto retry;
198 }
199 } else {
200 struct nilfs_super_block *sbp = nilfs->ns_sbp[0];
201
202 nilfs->ns_sbwcount++;
203
204 /*
205 * The latest segment becomes trailable from the position
206 * written in superblock.
207 */
208 clear_nilfs_discontinued(nilfs);
209
210 /* update GC protection for recent segments */
211 if (nilfs->ns_sbh[1]) {
212 if (flag == NILFS_SB_COMMIT_ALL) {
213 set_buffer_dirty(nilfs->ns_sbh[1]);
214 if (sync_dirty_buffer(nilfs->ns_sbh[1]) < 0)
215 goto out;
216 }
217 if (le64_to_cpu(nilfs->ns_sbp[1]->s_last_cno) <
218 le64_to_cpu(nilfs->ns_sbp[0]->s_last_cno))
219 sbp = nilfs->ns_sbp[1];
220 }
221
222 spin_lock(&nilfs->ns_last_segment_lock);
223 nilfs->ns_prot_seq = le64_to_cpu(sbp->s_last_seq);
224 spin_unlock(&nilfs->ns_last_segment_lock);
225 }
226 out:
227 return err;
228 }
229
230 void nilfs_set_log_cursor(struct nilfs_super_block *sbp,
231 struct the_nilfs *nilfs)
232 {
233 sector_t nfreeblocks;
234
235 /* nilfs->ns_sem must be locked by the caller. */
236 nilfs_count_free_blocks(nilfs, &nfreeblocks);
237 sbp->s_free_blocks_count = cpu_to_le64(nfreeblocks);
238
239 spin_lock(&nilfs->ns_last_segment_lock);
240 sbp->s_last_seq = cpu_to_le64(nilfs->ns_last_seq);
241 sbp->s_last_pseg = cpu_to_le64(nilfs->ns_last_pseg);
242 sbp->s_last_cno = cpu_to_le64(nilfs->ns_last_cno);
243 spin_unlock(&nilfs->ns_last_segment_lock);
244 }
245
246 struct nilfs_super_block **nilfs_prepare_super(struct super_block *sb,
247 int flip)
248 {
249 struct the_nilfs *nilfs = sb->s_fs_info;
250 struct nilfs_super_block **sbp = nilfs->ns_sbp;
251
252 /* nilfs->ns_sem must be locked by the caller. */
253 if (sbp[0]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) {
254 if (sbp[1] &&
255 sbp[1]->s_magic == cpu_to_le16(NILFS_SUPER_MAGIC)) {
256 memcpy(sbp[0], sbp[1], nilfs->ns_sbsize);
257 } else {
258 nilfs_crit(sb, "superblock broke");
259 return NULL;
260 }
261 } else if (sbp[1] &&
262 sbp[1]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) {
263 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
264 }
265
266 if (flip && sbp[1])
267 nilfs_swap_super_block(nilfs);
268
269 return sbp;
270 }
271
272 int nilfs_commit_super(struct super_block *sb, int flag)
273 {
274 struct the_nilfs *nilfs = sb->s_fs_info;
275 struct nilfs_super_block **sbp = nilfs->ns_sbp;
276 time64_t t;
277
278 /* nilfs->ns_sem must be locked by the caller. */
279 t = ktime_get_real_seconds();
280 nilfs->ns_sbwtime = t;
281 sbp[0]->s_wtime = cpu_to_le64(t);
282 sbp[0]->s_sum = 0;
283 sbp[0]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed,
284 (unsigned char *)sbp[0],
285 nilfs->ns_sbsize));
286 if (flag == NILFS_SB_COMMIT_ALL && sbp[1]) {
287 sbp[1]->s_wtime = sbp[0]->s_wtime;
288 sbp[1]->s_sum = 0;
289 sbp[1]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed,
290 (unsigned char *)sbp[1],
291 nilfs->ns_sbsize));
292 }
293 clear_nilfs_sb_dirty(nilfs);
294 nilfs->ns_flushed_device = 1;
295 /* make sure store to ns_flushed_device cannot be reordered */
296 smp_wmb();
297 return nilfs_sync_super(sb, flag);
298 }
299
300 /**
301 * nilfs_cleanup_super() - write filesystem state for cleanup
302 * @sb: super block instance to be unmounted or degraded to read-only
303 *
304 * This function restores state flags in the on-disk super block.
305 * This will set "clean" flag (i.e. NILFS_VALID_FS) unless the
306 * filesystem was not clean previously.
307 */
308 int nilfs_cleanup_super(struct super_block *sb)
309 {
310 struct the_nilfs *nilfs = sb->s_fs_info;
311 struct nilfs_super_block **sbp;
312 int flag = NILFS_SB_COMMIT;
313 int ret = -EIO;
314
315 sbp = nilfs_prepare_super(sb, 0);
316 if (sbp) {
317 sbp[0]->s_state = cpu_to_le16(nilfs->ns_mount_state);
318 nilfs_set_log_cursor(sbp[0], nilfs);
319 if (sbp[1] && sbp[0]->s_last_cno == sbp[1]->s_last_cno) {
320 /*
321 * make the "clean" flag also to the opposite
322 * super block if both super blocks point to
323 * the same checkpoint.
324 */
325 sbp[1]->s_state = sbp[0]->s_state;
326 flag = NILFS_SB_COMMIT_ALL;
327 }
328 ret = nilfs_commit_super(sb, flag);
329 }
330 return ret;
331 }
332
333 /**
334 * nilfs_move_2nd_super - relocate secondary super block
335 * @sb: super block instance
336 * @sb2off: new offset of the secondary super block (in bytes)
337 */
338 static int nilfs_move_2nd_super(struct super_block *sb, loff_t sb2off)
339 {
340 struct the_nilfs *nilfs = sb->s_fs_info;
341 struct buffer_head *nsbh;
342 struct nilfs_super_block *nsbp;
343 sector_t blocknr, newblocknr;
344 unsigned long offset;
345 int sb2i; /* array index of the secondary superblock */
346 int ret = 0;
347
348 /* nilfs->ns_sem must be locked by the caller. */
349 if (nilfs->ns_sbh[1] &&
350 nilfs->ns_sbh[1]->b_blocknr > nilfs->ns_first_data_block) {
351 sb2i = 1;
352 blocknr = nilfs->ns_sbh[1]->b_blocknr;
353 } else if (nilfs->ns_sbh[0]->b_blocknr > nilfs->ns_first_data_block) {
354 sb2i = 0;
355 blocknr = nilfs->ns_sbh[0]->b_blocknr;
356 } else {
357 sb2i = -1;
358 blocknr = 0;
359 }
360 if (sb2i >= 0 && (u64)blocknr << nilfs->ns_blocksize_bits == sb2off)
361 goto out; /* super block location is unchanged */
362
363 /* Get new super block buffer */
364 newblocknr = sb2off >> nilfs->ns_blocksize_bits;
365 offset = sb2off & (nilfs->ns_blocksize - 1);
366 nsbh = sb_getblk(sb, newblocknr);
367 if (!nsbh) {
368 nilfs_warn(sb,
369 "unable to move secondary superblock to block %llu",
370 (unsigned long long)newblocknr);
371 ret = -EIO;
372 goto out;
373 }
374 nsbp = (void *)nsbh->b_data + offset;
375
376 lock_buffer(nsbh);
377 if (sb2i >= 0) {
378 /*
379 * The position of the second superblock only changes by 4KiB,
380 * which is larger than the maximum superblock data size
381 * (= 1KiB), so there is no need to use memmove() to allow
382 * overlap between source and destination.
383 */
384 memcpy(nsbp, nilfs->ns_sbp[sb2i], nilfs->ns_sbsize);
385
386 /*
387 * Zero fill after copy to avoid overwriting in case of move
388 * within the same block.
389 */
390 memset(nsbh->b_data, 0, offset);
391 memset((void *)nsbp + nilfs->ns_sbsize, 0,
392 nsbh->b_size - offset - nilfs->ns_sbsize);
393 } else {
394 memset(nsbh->b_data, 0, nsbh->b_size);
395 }
396 set_buffer_uptodate(nsbh);
397 unlock_buffer(nsbh);
398
399 if (sb2i >= 0) {
400 brelse(nilfs->ns_sbh[sb2i]);
401 nilfs->ns_sbh[sb2i] = nsbh;
402 nilfs->ns_sbp[sb2i] = nsbp;
403 } else if (nilfs->ns_sbh[0]->b_blocknr < nilfs->ns_first_data_block) {
404 /* secondary super block will be restored to index 1 */
405 nilfs->ns_sbh[1] = nsbh;
406 nilfs->ns_sbp[1] = nsbp;
407 } else {
408 brelse(nsbh);
409 }
410 out:
411 return ret;
412 }
413
414 /**
415 * nilfs_resize_fs - resize the filesystem
416 * @sb: super block instance
417 * @newsize: new size of the filesystem (in bytes)
418 */
419 int nilfs_resize_fs(struct super_block *sb, __u64 newsize)
420 {
421 struct the_nilfs *nilfs = sb->s_fs_info;
422 struct nilfs_super_block **sbp;
423 __u64 devsize, newnsegs;
424 loff_t sb2off;
425 int ret;
426
427 ret = -ERANGE;
428 devsize = bdev_nr_bytes(sb->s_bdev);
429 if (newsize > devsize)
430 goto out;
431
432 /*
433 * Prevent underflow in second superblock position calculation.
434 * The exact minimum size check is done in nilfs_sufile_resize().
435 */
436 if (newsize < 4096) {
437 ret = -ENOSPC;
438 goto out;
439 }
440
441 /*
442 * Write lock is required to protect some functions depending
443 * on the number of segments, the number of reserved segments,
444 * and so forth.
445 */
446 down_write(&nilfs->ns_segctor_sem);
447
448 sb2off = NILFS_SB2_OFFSET_BYTES(newsize);
449 newnsegs = sb2off >> nilfs->ns_blocksize_bits;
450 newnsegs = div64_ul(newnsegs, nilfs->ns_blocks_per_segment);
451
452 ret = nilfs_sufile_resize(nilfs->ns_sufile, newnsegs);
453 up_write(&nilfs->ns_segctor_sem);
454 if (ret < 0)
455 goto out;
456
457 ret = nilfs_construct_segment(sb);
458 if (ret < 0)
459 goto out;
460
461 down_write(&nilfs->ns_sem);
462 nilfs_move_2nd_super(sb, sb2off);
463 ret = -EIO;
464 sbp = nilfs_prepare_super(sb, 0);
465 if (likely(sbp)) {
466 nilfs_set_log_cursor(sbp[0], nilfs);
467 /*
468 * Drop NILFS_RESIZE_FS flag for compatibility with
469 * mount-time resize which may be implemented in a
470 * future release.
471 */
472 sbp[0]->s_state = cpu_to_le16(le16_to_cpu(sbp[0]->s_state) &
473 ~NILFS_RESIZE_FS);
474 sbp[0]->s_dev_size = cpu_to_le64(newsize);
475 sbp[0]->s_nsegments = cpu_to_le64(nilfs->ns_nsegments);
476 if (sbp[1])
477 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
478 ret = nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL);
479 }
480 up_write(&nilfs->ns_sem);
481
482 /*
483 * Reset the range of allocatable segments last. This order
484 * is important in the case of expansion because the secondary
485 * superblock must be protected from log write until migration
486 * completes.
487 */
488 if (!ret)
489 nilfs_sufile_set_alloc_range(nilfs->ns_sufile, 0, newnsegs - 1);
490 out:
491 return ret;
492 }
493
494 static void nilfs_put_super(struct super_block *sb)
495 {
496 struct the_nilfs *nilfs = sb->s_fs_info;
497
498 nilfs_detach_log_writer(sb);
499
500 if (!sb_rdonly(sb)) {
501 down_write(&nilfs->ns_sem);
502 nilfs_cleanup_super(sb);
503 up_write(&nilfs->ns_sem);
504 }
505
506 nilfs_sysfs_delete_device_group(nilfs);
507 iput(nilfs->ns_sufile);
508 iput(nilfs->ns_cpfile);
509 iput(nilfs->ns_dat);
510
511 destroy_nilfs(nilfs);
512 sb->s_fs_info = NULL;
513 }
514
515 static int nilfs_sync_fs(struct super_block *sb, int wait)
516 {
517 struct the_nilfs *nilfs = sb->s_fs_info;
518 struct nilfs_super_block **sbp;
519 int err = 0;
520
521 /* This function is called when super block should be written back */
522 if (wait)
523 err = nilfs_construct_segment(sb);
524
525 down_write(&nilfs->ns_sem);
526 if (nilfs_sb_dirty(nilfs)) {
527 sbp = nilfs_prepare_super(sb, nilfs_sb_will_flip(nilfs));
528 if (likely(sbp)) {
529 nilfs_set_log_cursor(sbp[0], nilfs);
530 nilfs_commit_super(sb, NILFS_SB_COMMIT);
531 }
532 }
533 up_write(&nilfs->ns_sem);
534
535 if (!err)
536 err = nilfs_flush_device(nilfs);
537
538 return err;
539 }
540
541 int nilfs_attach_checkpoint(struct super_block *sb, __u64 cno, int curr_mnt,
542 struct nilfs_root **rootp)
543 {
544 struct the_nilfs *nilfs = sb->s_fs_info;
545 struct nilfs_root *root;
546 int err = -ENOMEM;
547
548 root = nilfs_find_or_create_root(
549 nilfs, curr_mnt ? NILFS_CPTREE_CURRENT_CNO : cno);
550 if (!root)
551 return err;
552
553 if (root->ifile)
554 goto reuse; /* already attached checkpoint */
555
556 down_read(&nilfs->ns_segctor_sem);
557 err = nilfs_ifile_read(sb, root, cno, nilfs->ns_inode_size);
558 up_read(&nilfs->ns_segctor_sem);
559 if (unlikely(err))
560 goto failed;
561
562 reuse:
563 *rootp = root;
564 return 0;
565
566 failed:
567 if (err == -EINVAL)
568 nilfs_err(sb, "Invalid checkpoint (checkpoint number=%llu)",
569 (unsigned long long)cno);
570 nilfs_put_root(root);
571
572 return err;
573 }
574
575 static int nilfs_freeze(struct super_block *sb)
576 {
577 struct the_nilfs *nilfs = sb->s_fs_info;
578 int err;
579
580 if (sb_rdonly(sb))
581 return 0;
582
583 /* Mark super block clean */
584 down_write(&nilfs->ns_sem);
585 err = nilfs_cleanup_super(sb);
586 up_write(&nilfs->ns_sem);
587 return err;
588 }
589
590 static int nilfs_unfreeze(struct super_block *sb)
591 {
592 struct the_nilfs *nilfs = sb->s_fs_info;
593
594 if (sb_rdonly(sb))
595 return 0;
596
597 down_write(&nilfs->ns_sem);
598 nilfs_setup_super(sb, false);
599 up_write(&nilfs->ns_sem);
600 return 0;
601 }
602
603 static int nilfs_statfs(struct dentry *dentry, struct kstatfs *buf)
604 {
605 struct super_block *sb = dentry->d_sb;
606 struct nilfs_root *root = NILFS_I(d_inode(dentry))->i_root;
607 struct the_nilfs *nilfs = root->nilfs;
608 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
609 unsigned long long blocks;
610 unsigned long overhead;
611 unsigned long nrsvblocks;
612 sector_t nfreeblocks;
613 u64 nmaxinodes, nfreeinodes;
614 int err;
615
616 /*
617 * Compute all of the segment blocks
618 *
619 * The blocks before first segment and after last segment
620 * are excluded.
621 */
622 blocks = nilfs->ns_blocks_per_segment * nilfs->ns_nsegments
623 - nilfs->ns_first_data_block;
624 nrsvblocks = nilfs->ns_nrsvsegs * nilfs->ns_blocks_per_segment;
625
626 /*
627 * Compute the overhead
628 *
629 * When distributing meta data blocks outside segment structure,
630 * We must count them as the overhead.
631 */
632 overhead = 0;
633
634 err = nilfs_count_free_blocks(nilfs, &nfreeblocks);
635 if (unlikely(err))
636 return err;
637
638 err = nilfs_ifile_count_free_inodes(root->ifile,
639 &nmaxinodes, &nfreeinodes);
640 if (unlikely(err)) {
641 nilfs_warn(sb, "failed to count free inodes: err=%d", err);
642 if (err == -ERANGE) {
643 /*
644 * If nilfs_palloc_count_max_entries() returns
645 * -ERANGE error code then we simply treat
646 * curent inodes count as maximum possible and
647 * zero as free inodes value.
648 */
649 nmaxinodes = atomic64_read(&root->inodes_count);
650 nfreeinodes = 0;
651 err = 0;
652 } else
653 return err;
654 }
655
656 buf->f_type = NILFS_SUPER_MAGIC;
657 buf->f_bsize = sb->s_blocksize;
658 buf->f_blocks = blocks - overhead;
659 buf->f_bfree = nfreeblocks;
660 buf->f_bavail = (buf->f_bfree >= nrsvblocks) ?
661 (buf->f_bfree - nrsvblocks) : 0;
662 buf->f_files = nmaxinodes;
663 buf->f_ffree = nfreeinodes;
664 buf->f_namelen = NILFS_NAME_LEN;
665 buf->f_fsid = u64_to_fsid(id);
666
667 return 0;
668 }
669
670 static int nilfs_show_options(struct seq_file *seq, struct dentry *dentry)
671 {
672 struct super_block *sb = dentry->d_sb;
673 struct the_nilfs *nilfs = sb->s_fs_info;
674 struct nilfs_root *root = NILFS_I(d_inode(dentry))->i_root;
675
676 if (!nilfs_test_opt(nilfs, BARRIER))
677 seq_puts(seq, ",nobarrier");
678 if (root->cno != NILFS_CPTREE_CURRENT_CNO)
679 seq_printf(seq, ",cp=%llu", (unsigned long long)root->cno);
680 if (nilfs_test_opt(nilfs, ERRORS_PANIC))
681 seq_puts(seq, ",errors=panic");
682 if (nilfs_test_opt(nilfs, ERRORS_CONT))
683 seq_puts(seq, ",errors=continue");
684 if (nilfs_test_opt(nilfs, STRICT_ORDER))
685 seq_puts(seq, ",order=strict");
686 if (nilfs_test_opt(nilfs, NORECOVERY))
687 seq_puts(seq, ",norecovery");
688 if (nilfs_test_opt(nilfs, DISCARD))
689 seq_puts(seq, ",discard");
690
691 return 0;
692 }
693
694 static const struct super_operations nilfs_sops = {
695 .alloc_inode = nilfs_alloc_inode,
696 .free_inode = nilfs_free_inode,
697 .dirty_inode = nilfs_dirty_inode,
698 .evict_inode = nilfs_evict_inode,
699 .put_super = nilfs_put_super,
700 .sync_fs = nilfs_sync_fs,
701 .freeze_fs = nilfs_freeze,
702 .unfreeze_fs = nilfs_unfreeze,
703 .statfs = nilfs_statfs,
704 .show_options = nilfs_show_options
705 };
706
707 enum {
708 Opt_err, Opt_barrier, Opt_snapshot, Opt_order, Opt_norecovery,
709 Opt_discard,
710 };
711
712 static const struct constant_table nilfs_param_err[] = {
713 {"continue", NILFS_MOUNT_ERRORS_CONT},
714 {"panic", NILFS_MOUNT_ERRORS_PANIC},
715 {"remount-ro", NILFS_MOUNT_ERRORS_RO},
716 {}
717 };
718
719 static const struct fs_parameter_spec nilfs_param_spec[] = {
720 fsparam_enum ("errors", Opt_err, nilfs_param_err),
721 fsparam_flag_no ("barrier", Opt_barrier),
722 fsparam_u64 ("cp", Opt_snapshot),
723 fsparam_string ("order", Opt_order),
724 fsparam_flag ("norecovery", Opt_norecovery),
725 fsparam_flag_no ("discard", Opt_discard),
726 {}
727 };
728
729 struct nilfs_fs_context {
730 unsigned long ns_mount_opt;
731 __u64 cno;
732 };
733
734 static int nilfs_parse_param(struct fs_context *fc, struct fs_parameter *param)
735 {
736 struct nilfs_fs_context *nilfs = fc->fs_private;
737 int is_remount = fc->purpose == FS_CONTEXT_FOR_RECONFIGURE;
738 struct fs_parse_result result;
739 int opt;
740
741 opt = fs_parse(fc, nilfs_param_spec, param, &result);
742 if (opt < 0)
743 return opt;
744
745 switch (opt) {
746 case Opt_barrier:
747 if (result.negated)
748 nilfs_clear_opt(nilfs, BARRIER);
749 else
750 nilfs_set_opt(nilfs, BARRIER);
751 break;
752 case Opt_order:
753 if (strcmp(param->string, "relaxed") == 0)
754 /* Ordered data semantics */
755 nilfs_clear_opt(nilfs, STRICT_ORDER);
756 else if (strcmp(param->string, "strict") == 0)
757 /* Strict in-order semantics */
758 nilfs_set_opt(nilfs, STRICT_ORDER);
759 else
760 return -EINVAL;
761 break;
762 case Opt_err:
763 nilfs->ns_mount_opt &= ~NILFS_MOUNT_ERROR_MODE;
764 nilfs->ns_mount_opt |= result.uint_32;
765 break;
766 case Opt_snapshot:
767 if (is_remount) {
768 struct super_block *sb = fc->root->d_sb;
769
770 nilfs_err(sb,
771 "\"%s\" option is invalid for remount",
772 param->key);
773 return -EINVAL;
774 }
775 if (result.uint_64 == 0) {
776 nilfs_err(NULL,
777 "invalid option \"cp=0\": invalid checkpoint number 0");
778 return -EINVAL;
779 }
780 nilfs->cno = result.uint_64;
781 break;
782 case Opt_norecovery:
783 nilfs_set_opt(nilfs, NORECOVERY);
784 break;
785 case Opt_discard:
786 if (result.negated)
787 nilfs_clear_opt(nilfs, DISCARD);
788 else
789 nilfs_set_opt(nilfs, DISCARD);
790 break;
791 default:
792 return -EINVAL;
793 }
794
795 return 0;
796 }
797
798 static int nilfs_setup_super(struct super_block *sb, int is_mount)
799 {
800 struct the_nilfs *nilfs = sb->s_fs_info;
801 struct nilfs_super_block **sbp;
802 int max_mnt_count;
803 int mnt_count;
804
805 /* nilfs->ns_sem must be locked by the caller. */
806 sbp = nilfs_prepare_super(sb, 0);
807 if (!sbp)
808 return -EIO;
809
810 if (!is_mount)
811 goto skip_mount_setup;
812
813 max_mnt_count = le16_to_cpu(sbp[0]->s_max_mnt_count);
814 mnt_count = le16_to_cpu(sbp[0]->s_mnt_count);
815
816 if (nilfs->ns_mount_state & NILFS_ERROR_FS) {
817 nilfs_warn(sb, "mounting fs with errors");
818 #if 0
819 } else if (max_mnt_count >= 0 && mnt_count >= max_mnt_count) {
820 nilfs_warn(sb, "maximal mount count reached");
821 #endif
822 }
823 if (!max_mnt_count)
824 sbp[0]->s_max_mnt_count = cpu_to_le16(NILFS_DFL_MAX_MNT_COUNT);
825
826 sbp[0]->s_mnt_count = cpu_to_le16(mnt_count + 1);
827 sbp[0]->s_mtime = cpu_to_le64(ktime_get_real_seconds());
828
829 skip_mount_setup:
830 sbp[0]->s_state =
831 cpu_to_le16(le16_to_cpu(sbp[0]->s_state) & ~NILFS_VALID_FS);
832 /* synchronize sbp[1] with sbp[0] */
833 if (sbp[1])
834 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
835 return nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL);
836 }
837
838 struct nilfs_super_block *nilfs_read_super_block(struct super_block *sb,
839 u64 pos, int blocksize,
840 struct buffer_head **pbh)
841 {
842 unsigned long long sb_index = pos;
843 unsigned long offset;
844
845 offset = do_div(sb_index, blocksize);
846 *pbh = sb_bread(sb, sb_index);
847 if (!*pbh)
848 return NULL;
849 return (struct nilfs_super_block *)((char *)(*pbh)->b_data + offset);
850 }
851
852 int nilfs_store_magic(struct super_block *sb,
853 struct nilfs_super_block *sbp)
854 {
855 struct the_nilfs *nilfs = sb->s_fs_info;
856
857 sb->s_magic = le16_to_cpu(sbp->s_magic);
858
859 /* FS independent flags */
860 #ifdef NILFS_ATIME_DISABLE
861 sb->s_flags |= SB_NOATIME;
862 #endif
863
864 nilfs->ns_resuid = le16_to_cpu(sbp->s_def_resuid);
865 nilfs->ns_resgid = le16_to_cpu(sbp->s_def_resgid);
866 nilfs->ns_interval = le32_to_cpu(sbp->s_c_interval);
867 nilfs->ns_watermark = le32_to_cpu(sbp->s_c_block_max);
868
869 return 0;
870 }
871
872 int nilfs_check_feature_compatibility(struct super_block *sb,
873 struct nilfs_super_block *sbp)
874 {
875 __u64 features;
876
877 features = le64_to_cpu(sbp->s_feature_incompat) &
878 ~NILFS_FEATURE_INCOMPAT_SUPP;
879 if (features) {
880 nilfs_err(sb,
881 "couldn't mount because of unsupported optional features (%llx)",
882 (unsigned long long)features);
883 return -EINVAL;
884 }
885 features = le64_to_cpu(sbp->s_feature_compat_ro) &
886 ~NILFS_FEATURE_COMPAT_RO_SUPP;
887 if (!sb_rdonly(sb) && features) {
888 nilfs_err(sb,
889 "couldn't mount RDWR because of unsupported optional features (%llx)",
890 (unsigned long long)features);
891 return -EINVAL;
892 }
893 return 0;
894 }
895
896 static int nilfs_get_root_dentry(struct super_block *sb,
897 struct nilfs_root *root,
898 struct dentry **root_dentry)
899 {
900 struct inode *inode;
901 struct dentry *dentry;
902 int ret = 0;
903
904 inode = nilfs_iget(sb, root, NILFS_ROOT_INO);
905 if (IS_ERR(inode)) {
906 ret = PTR_ERR(inode);
907 nilfs_err(sb, "error %d getting root inode", ret);
908 goto out;
909 }
910 if (!S_ISDIR(inode->i_mode) || !inode->i_blocks || !inode->i_size) {
911 iput(inode);
912 nilfs_err(sb, "corrupt root inode");
913 ret = -EINVAL;
914 goto out;
915 }
916
917 if (root->cno == NILFS_CPTREE_CURRENT_CNO) {
918 dentry = d_find_alias(inode);
919 if (!dentry) {
920 dentry = d_make_root(inode);
921 if (!dentry) {
922 ret = -ENOMEM;
923 goto failed_dentry;
924 }
925 } else {
926 iput(inode);
927 }
928 } else {
929 dentry = d_obtain_root(inode);
930 if (IS_ERR(dentry)) {
931 ret = PTR_ERR(dentry);
932 goto failed_dentry;
933 }
934 }
935 *root_dentry = dentry;
936 out:
937 return ret;
938
939 failed_dentry:
940 nilfs_err(sb, "error %d getting root dentry", ret);
941 goto out;
942 }
943
944 static int nilfs_attach_snapshot(struct super_block *s, __u64 cno,
945 struct dentry **root_dentry)
946 {
947 struct the_nilfs *nilfs = s->s_fs_info;
948 struct nilfs_root *root;
949 int ret;
950
951 mutex_lock(&nilfs->ns_snapshot_mount_mutex);
952
953 down_read(&nilfs->ns_segctor_sem);
954 ret = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile, cno);
955 up_read(&nilfs->ns_segctor_sem);
956 if (ret < 0) {
957 ret = (ret == -ENOENT) ? -EINVAL : ret;
958 goto out;
959 } else if (!ret) {
960 nilfs_err(s,
961 "The specified checkpoint is not a snapshot (checkpoint number=%llu)",
962 (unsigned long long)cno);
963 ret = -EINVAL;
964 goto out;
965 }
966
967 ret = nilfs_attach_checkpoint(s, cno, false, &root);
968 if (ret) {
969 nilfs_err(s,
970 "error %d while loading snapshot (checkpoint number=%llu)",
971 ret, (unsigned long long)cno);
972 goto out;
973 }
974 ret = nilfs_get_root_dentry(s, root, root_dentry);
975 nilfs_put_root(root);
976 out:
977 mutex_unlock(&nilfs->ns_snapshot_mount_mutex);
978 return ret;
979 }
980
981 /**
982 * nilfs_tree_is_busy() - try to shrink dentries of a checkpoint
983 * @root_dentry: root dentry of the tree to be shrunk
984 *
985 * This function returns true if the tree was in-use.
986 */
987 static bool nilfs_tree_is_busy(struct dentry *root_dentry)
988 {
989 shrink_dcache_parent(root_dentry);
990 return d_count(root_dentry) > 1;
991 }
992
993 int nilfs_checkpoint_is_mounted(struct super_block *sb, __u64 cno)
994 {
995 struct the_nilfs *nilfs = sb->s_fs_info;
996 struct nilfs_root *root;
997 struct inode *inode;
998 struct dentry *dentry;
999 int ret;
1000
1001 if (cno > nilfs->ns_cno)
1002 return false;
1003
1004 if (cno >= nilfs_last_cno(nilfs))
1005 return true; /* protect recent checkpoints */
1006
1007 ret = false;
1008 root = nilfs_lookup_root(nilfs, cno);
1009 if (root) {
1010 inode = nilfs_ilookup(sb, root, NILFS_ROOT_INO);
1011 if (inode) {
1012 dentry = d_find_alias(inode);
1013 if (dentry) {
1014 ret = nilfs_tree_is_busy(dentry);
1015 dput(dentry);
1016 }
1017 iput(inode);
1018 }
1019 nilfs_put_root(root);
1020 }
1021 return ret;
1022 }
1023
1024 /**
1025 * nilfs_fill_super() - initialize a super block instance
1026 * @sb: super_block
1027 * @fc: filesystem context
1028 *
1029 * This function is called exclusively by nilfs->ns_mount_mutex.
1030 * So, the recovery process is protected from other simultaneous mounts.
1031 */
1032 static int
1033 nilfs_fill_super(struct super_block *sb, struct fs_context *fc)
1034 {
1035 struct the_nilfs *nilfs;
1036 struct nilfs_root *fsroot;
1037 struct nilfs_fs_context *ctx = fc->fs_private;
1038 __u64 cno;
1039 int err;
1040
1041 nilfs = alloc_nilfs(sb);
1042 if (!nilfs)
1043 return -ENOMEM;
1044
1045 sb->s_fs_info = nilfs;
1046
1047 err = init_nilfs(nilfs, sb);
1048 if (err)
1049 goto failed_nilfs;
1050
1051 /* Copy in parsed mount options */
1052 nilfs->ns_mount_opt = ctx->ns_mount_opt;
1053
1054 sb->s_op = &nilfs_sops;
1055 sb->s_export_op = &nilfs_export_ops;
1056 sb->s_root = NULL;
1057 sb->s_time_gran = 1;
1058 sb->s_max_links = NILFS_LINK_MAX;
1059
1060 sb->s_bdi = bdi_get(sb->s_bdev->bd_disk->bdi);
1061
1062 err = load_nilfs(nilfs, sb);
1063 if (err)
1064 goto failed_nilfs;
1065
1066 cno = nilfs_last_cno(nilfs);
1067 err = nilfs_attach_checkpoint(sb, cno, true, &fsroot);
1068 if (err) {
1069 nilfs_err(sb,
1070 "error %d while loading last checkpoint (checkpoint number=%llu)",
1071 err, (unsigned long long)cno);
1072 goto failed_unload;
1073 }
1074
1075 if (!sb_rdonly(sb)) {
1076 err = nilfs_attach_log_writer(sb, fsroot);
1077 if (err)
1078 goto failed_checkpoint;
1079 }
1080
1081 err = nilfs_get_root_dentry(sb, fsroot, &sb->s_root);
1082 if (err)
1083 goto failed_segctor;
1084
1085 nilfs_put_root(fsroot);
1086
1087 if (!sb_rdonly(sb)) {
1088 down_write(&nilfs->ns_sem);
1089 nilfs_setup_super(sb, true);
1090 up_write(&nilfs->ns_sem);
1091 }
1092
1093 return 0;
1094
1095 failed_segctor:
1096 nilfs_detach_log_writer(sb);
1097
1098 failed_checkpoint:
1099 nilfs_put_root(fsroot);
1100
1101 failed_unload:
1102 nilfs_sysfs_delete_device_group(nilfs);
1103 iput(nilfs->ns_sufile);
1104 iput(nilfs->ns_cpfile);
1105 iput(nilfs->ns_dat);
1106
1107 failed_nilfs:
1108 destroy_nilfs(nilfs);
1109 return err;
1110 }
1111
1112 static int nilfs_reconfigure(struct fs_context *fc)
1113 {
1114 struct nilfs_fs_context *ctx = fc->fs_private;
1115 struct super_block *sb = fc->root->d_sb;
1116 struct the_nilfs *nilfs = sb->s_fs_info;
1117 int err;
1118
1119 sync_filesystem(sb);
1120
1121 err = -EINVAL;
1122
1123 if (!nilfs_valid_fs(nilfs)) {
1124 nilfs_warn(sb,
1125 "couldn't remount because the filesystem is in an incomplete recovery state");
1126 goto ignore_opts;
1127 }
1128 if ((bool)(fc->sb_flags & SB_RDONLY) == sb_rdonly(sb))
1129 goto out;
1130 if (fc->sb_flags & SB_RDONLY) {
1131 sb->s_flags |= SB_RDONLY;
1132
1133 /*
1134 * Remounting a valid RW partition RDONLY, so set
1135 * the RDONLY flag and then mark the partition as valid again.
1136 */
1137 down_write(&nilfs->ns_sem);
1138 nilfs_cleanup_super(sb);
1139 up_write(&nilfs->ns_sem);
1140 } else {
1141 __u64 features;
1142 struct nilfs_root *root;
1143
1144 /*
1145 * Mounting a RDONLY partition read-write, so reread and
1146 * store the current valid flag. (It may have been changed
1147 * by fsck since we originally mounted the partition.)
1148 */
1149 down_read(&nilfs->ns_sem);
1150 features = le64_to_cpu(nilfs->ns_sbp[0]->s_feature_compat_ro) &
1151 ~NILFS_FEATURE_COMPAT_RO_SUPP;
1152 up_read(&nilfs->ns_sem);
1153 if (features) {
1154 nilfs_warn(sb,
1155 "couldn't remount RDWR because of unsupported optional features (%llx)",
1156 (unsigned long long)features);
1157 err = -EROFS;
1158 goto ignore_opts;
1159 }
1160
1161 sb->s_flags &= ~SB_RDONLY;
1162
1163 root = NILFS_I(d_inode(sb->s_root))->i_root;
1164 err = nilfs_attach_log_writer(sb, root);
1165 if (err) {
1166 sb->s_flags |= SB_RDONLY;
1167 goto ignore_opts;
1168 }
1169
1170 down_write(&nilfs->ns_sem);
1171 nilfs_setup_super(sb, true);
1172 up_write(&nilfs->ns_sem);
1173 }
1174 out:
1175 sb->s_flags = (sb->s_flags & ~SB_POSIXACL);
1176 /* Copy over parsed remount options */
1177 nilfs->ns_mount_opt = ctx->ns_mount_opt;
1178
1179 return 0;
1180
1181 ignore_opts:
1182 return err;
1183 }
1184
1185 static int
1186 nilfs_get_tree(struct fs_context *fc)
1187 {
1188 struct nilfs_fs_context *ctx = fc->fs_private;
1189 struct super_block *s;
1190 dev_t dev;
1191 int err;
1192
1193 if (ctx->cno && !(fc->sb_flags & SB_RDONLY)) {
1194 nilfs_err(NULL,
1195 "invalid option \"cp=%llu\": read-only option is not specified",
1196 ctx->cno);
1197 return -EINVAL;
1198 }
1199
1200 err = lookup_bdev(fc->source, &dev);
1201 if (err)
1202 return err;
1203
1204 s = sget_dev(fc, dev);
1205 if (IS_ERR(s))
1206 return PTR_ERR(s);
1207
1208 if (!s->s_root) {
1209 err = setup_bdev_super(s, fc->sb_flags, fc);
1210 if (!err)
1211 err = nilfs_fill_super(s, fc);
1212 if (err)
1213 goto failed_super;
1214
1215 s->s_flags |= SB_ACTIVE;
1216 } else if (!ctx->cno) {
1217 if (nilfs_tree_is_busy(s->s_root)) {
1218 if ((fc->sb_flags ^ s->s_flags) & SB_RDONLY) {
1219 nilfs_err(s,
1220 "the device already has a %s mount.",
1221 sb_rdonly(s) ? "read-only" : "read/write");
1222 err = -EBUSY;
1223 goto failed_super;
1224 }
1225 } else {
1226 /*
1227 * Try reconfigure to setup mount states if the current
1228 * tree is not mounted and only snapshots use this sb.
1229 *
1230 * Since nilfs_reconfigure() requires fc->root to be
1231 * set, set it first and release it on failure.
1232 */
1233 fc->root = dget(s->s_root);
1234 err = nilfs_reconfigure(fc);
1235 if (err) {
1236 dput(fc->root);
1237 fc->root = NULL; /* prevent double release */
1238 goto failed_super;
1239 }
1240 return 0;
1241 }
1242 }
1243
1244 if (ctx->cno) {
1245 struct dentry *root_dentry;
1246
1247 err = nilfs_attach_snapshot(s, ctx->cno, &root_dentry);
1248 if (err)
1249 goto failed_super;
1250 fc->root = root_dentry;
1251 return 0;
1252 }
1253
1254 fc->root = dget(s->s_root);
1255 return 0;
1256
1257 failed_super:
1258 deactivate_locked_super(s);
1259 return err;
1260 }
1261
1262 static void nilfs_free_fc(struct fs_context *fc)
1263 {
1264 kfree(fc->fs_private);
1265 }
1266
1267 static const struct fs_context_operations nilfs_context_ops = {
1268 .parse_param = nilfs_parse_param,
1269 .get_tree = nilfs_get_tree,
1270 .reconfigure = nilfs_reconfigure,
1271 .free = nilfs_free_fc,
1272 };
1273
1274 static int nilfs_init_fs_context(struct fs_context *fc)
1275 {
1276 struct nilfs_fs_context *ctx;
1277
1278 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
1279 if (!ctx)
1280 return -ENOMEM;
1281
1282 ctx->ns_mount_opt = NILFS_MOUNT_ERRORS_RO | NILFS_MOUNT_BARRIER;
1283 fc->fs_private = ctx;
1284 fc->ops = &nilfs_context_ops;
1285
1286 return 0;
1287 }
1288
1289 struct file_system_type nilfs_fs_type = {
1290 .owner = THIS_MODULE,
1291 .name = "nilfs2",
1292 .kill_sb = kill_block_super,
1293 .fs_flags = FS_REQUIRES_DEV,
1294 .init_fs_context = nilfs_init_fs_context,
1295 .parameters = nilfs_param_spec,
1296 };
1297 MODULE_ALIAS_FS("nilfs2");
1298
1299 static void nilfs_inode_init_once(void *obj)
1300 {
1301 struct nilfs_inode_info *ii = obj;
1302
1303 INIT_LIST_HEAD(&ii->i_dirty);
1304 #ifdef CONFIG_NILFS_XATTR
1305 init_rwsem(&ii->xattr_sem);
1306 #endif
1307 inode_init_once(&ii->vfs_inode);
1308 }
1309
1310 static void nilfs_segbuf_init_once(void *obj)
1311 {
1312 memset(obj, 0, sizeof(struct nilfs_segment_buffer));
1313 }
1314
1315 static void nilfs_destroy_cachep(void)
1316 {
1317 /*
1318 * Make sure all delayed rcu free inodes are flushed before we
1319 * destroy cache.
1320 */
1321 rcu_barrier();
1322
1323 kmem_cache_destroy(nilfs_inode_cachep);
1324 kmem_cache_destroy(nilfs_transaction_cachep);
1325 kmem_cache_destroy(nilfs_segbuf_cachep);
1326 kmem_cache_destroy(nilfs_btree_path_cache);
1327 }
1328
1329 static int __init nilfs_init_cachep(void)
1330 {
1331 nilfs_inode_cachep = kmem_cache_create("nilfs2_inode_cache",
1332 sizeof(struct nilfs_inode_info), 0,
1333 SLAB_RECLAIM_ACCOUNT|SLAB_ACCOUNT,
1334 nilfs_inode_init_once);
1335 if (!nilfs_inode_cachep)
1336 goto fail;
1337
1338 nilfs_transaction_cachep = kmem_cache_create("nilfs2_transaction_cache",
1339 sizeof(struct nilfs_transaction_info), 0,
1340 SLAB_RECLAIM_ACCOUNT, NULL);
1341 if (!nilfs_transaction_cachep)
1342 goto fail;
1343
1344 nilfs_segbuf_cachep = kmem_cache_create("nilfs2_segbuf_cache",
1345 sizeof(struct nilfs_segment_buffer), 0,
1346 SLAB_RECLAIM_ACCOUNT, nilfs_segbuf_init_once);
1347 if (!nilfs_segbuf_cachep)
1348 goto fail;
1349
1350 nilfs_btree_path_cache = kmem_cache_create("nilfs2_btree_path_cache",
1351 sizeof(struct nilfs_btree_path) * NILFS_BTREE_LEVEL_MAX,
1352 0, 0, NULL);
1353 if (!nilfs_btree_path_cache)
1354 goto fail;
1355
1356 return 0;
1357
1358 fail:
1359 nilfs_destroy_cachep();
1360 return -ENOMEM;
1361 }
1362
1363 static int __init init_nilfs_fs(void)
1364 {
1365 int err;
1366
1367 err = nilfs_init_cachep();
1368 if (err)
1369 goto fail;
1370
1371 err = nilfs_sysfs_init();
1372 if (err)
1373 goto free_cachep;
1374
1375 err = register_filesystem(&nilfs_fs_type);
1376 if (err)
1377 goto deinit_sysfs_entry;
1378
1379 printk(KERN_INFO "NILFS version 2 loaded\n");
1380 return 0;
1381
1382 deinit_sysfs_entry:
1383 nilfs_sysfs_exit();
1384 free_cachep:
1385 nilfs_destroy_cachep();
1386 fail:
1387 return err;
1388 }
1389
1390 static void __exit exit_nilfs_fs(void)
1391 {
1392 nilfs_destroy_cachep();
1393 nilfs_sysfs_exit();
1394 unregister_filesystem(&nilfs_fs_type);
1395 }
1396
1397 module_init(init_nilfs_fs)
1398 module_exit(exit_nilfs_fs)
1399
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