gspca: Fix falling back to lower isoc alt settings
[zen-stable.git] / fs / nilfs2 / super.c
blob8351c44a7320f06902bf03dcc114ade367c22fbe
1 /*
2 * super.c - NILFS module and super block management.
4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
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.
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.
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
20 * Written by Ryusuke Konishi <ryusuke@osrg.net>
23 * linux/fs/ext2/super.c
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)
30 * from
32 * linux/fs/minix/inode.c
34 * Copyright (C) 1991, 1992 Linus Torvalds
36 * Big-endian to little-endian byte-swapping/bitmaps by
37 * David S. Miller (davem@caip.rutgers.edu), 1995
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/crc32.h>
47 #include <linux/vfs.h>
48 #include <linux/writeback.h>
49 #include <linux/seq_file.h>
50 #include <linux/mount.h>
51 #include "nilfs.h"
52 #include "export.h"
53 #include "mdt.h"
54 #include "alloc.h"
55 #include "btree.h"
56 #include "btnode.h"
57 #include "page.h"
58 #include "cpfile.h"
59 #include "sufile.h" /* nilfs_sufile_resize(), nilfs_sufile_set_alloc_range() */
60 #include "ifile.h"
61 #include "dat.h"
62 #include "segment.h"
63 #include "segbuf.h"
65 MODULE_AUTHOR("NTT Corp.");
66 MODULE_DESCRIPTION("A New Implementation of the Log-structured Filesystem "
67 "(NILFS)");
68 MODULE_LICENSE("GPL");
70 static struct kmem_cache *nilfs_inode_cachep;
71 struct kmem_cache *nilfs_transaction_cachep;
72 struct kmem_cache *nilfs_segbuf_cachep;
73 struct kmem_cache *nilfs_btree_path_cache;
75 static int nilfs_setup_super(struct super_block *sb, int is_mount);
76 static int nilfs_remount(struct super_block *sb, int *flags, char *data);
78 static void nilfs_set_error(struct super_block *sb)
80 struct the_nilfs *nilfs = sb->s_fs_info;
81 struct nilfs_super_block **sbp;
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(sb, 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(sb, NILFS_SB_COMMIT_ALL);
94 up_write(&nilfs->ns_sem);
97 /**
98 * nilfs_error() - report failure condition on a filesystem
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.
106 * The segment constructor must not call this function because it can
107 * kill itself.
109 void nilfs_error(struct super_block *sb, const char *function,
110 const char *fmt, ...)
112 struct the_nilfs *nilfs = sb->s_fs_info;
113 struct va_format vaf;
114 va_list args;
116 va_start(args, fmt);
118 vaf.fmt = fmt;
119 vaf.va = &args;
121 printk(KERN_CRIT "NILFS error (device %s): %s: %pV\n",
122 sb->s_id, function, &vaf);
124 va_end(args);
126 if (!(sb->s_flags & MS_RDONLY)) {
127 nilfs_set_error(sb);
129 if (nilfs_test_opt(nilfs, ERRORS_RO)) {
130 printk(KERN_CRIT "Remounting filesystem read-only\n");
131 sb->s_flags |= MS_RDONLY;
135 if (nilfs_test_opt(nilfs, ERRORS_PANIC))
136 panic("NILFS (device %s): panic forced after error\n",
137 sb->s_id);
140 void nilfs_warning(struct super_block *sb, const char *function,
141 const char *fmt, ...)
143 struct va_format vaf;
144 va_list args;
146 va_start(args, fmt);
148 vaf.fmt = fmt;
149 vaf.va = &args;
151 printk(KERN_WARNING "NILFS warning (device %s): %s: %pV\n",
152 sb->s_id, function, &vaf);
154 va_end(args);
158 struct inode *nilfs_alloc_inode(struct super_block *sb)
160 struct nilfs_inode_info *ii;
162 ii = kmem_cache_alloc(nilfs_inode_cachep, GFP_NOFS);
163 if (!ii)
164 return NULL;
165 ii->i_bh = NULL;
166 ii->i_state = 0;
167 ii->i_cno = 0;
168 ii->vfs_inode.i_version = 1;
169 nilfs_mapping_init(&ii->i_btnode_cache, &ii->vfs_inode, sb->s_bdi);
170 return &ii->vfs_inode;
173 static void nilfs_i_callback(struct rcu_head *head)
175 struct inode *inode = container_of(head, struct inode, i_rcu);
176 struct nilfs_mdt_info *mdi = NILFS_MDT(inode);
178 INIT_LIST_HEAD(&inode->i_dentry);
180 if (mdi) {
181 kfree(mdi->mi_bgl); /* kfree(NULL) is safe */
182 kfree(mdi);
184 kmem_cache_free(nilfs_inode_cachep, NILFS_I(inode));
187 void nilfs_destroy_inode(struct inode *inode)
189 call_rcu(&inode->i_rcu, nilfs_i_callback);
192 static int nilfs_sync_super(struct super_block *sb, int flag)
194 struct the_nilfs *nilfs = sb->s_fs_info;
195 int err;
197 retry:
198 set_buffer_dirty(nilfs->ns_sbh[0]);
199 if (nilfs_test_opt(nilfs, BARRIER)) {
200 err = __sync_dirty_buffer(nilfs->ns_sbh[0],
201 WRITE_SYNC | WRITE_FLUSH_FUA);
202 } else {
203 err = sync_dirty_buffer(nilfs->ns_sbh[0]);
206 if (unlikely(err)) {
207 printk(KERN_ERR
208 "NILFS: unable to write superblock (err=%d)\n", err);
209 if (err == -EIO && nilfs->ns_sbh[1]) {
211 * sbp[0] points to newer log than sbp[1],
212 * so copy sbp[0] to sbp[1] to take over sbp[0].
214 memcpy(nilfs->ns_sbp[1], nilfs->ns_sbp[0],
215 nilfs->ns_sbsize);
216 nilfs_fall_back_super_block(nilfs);
217 goto retry;
219 } else {
220 struct nilfs_super_block *sbp = nilfs->ns_sbp[0];
222 nilfs->ns_sbwcount++;
225 * The latest segment becomes trailable from the position
226 * written in superblock.
228 clear_nilfs_discontinued(nilfs);
230 /* update GC protection for recent segments */
231 if (nilfs->ns_sbh[1]) {
232 if (flag == NILFS_SB_COMMIT_ALL) {
233 set_buffer_dirty(nilfs->ns_sbh[1]);
234 if (sync_dirty_buffer(nilfs->ns_sbh[1]) < 0)
235 goto out;
237 if (le64_to_cpu(nilfs->ns_sbp[1]->s_last_cno) <
238 le64_to_cpu(nilfs->ns_sbp[0]->s_last_cno))
239 sbp = nilfs->ns_sbp[1];
242 spin_lock(&nilfs->ns_last_segment_lock);
243 nilfs->ns_prot_seq = le64_to_cpu(sbp->s_last_seq);
244 spin_unlock(&nilfs->ns_last_segment_lock);
246 out:
247 return err;
250 void nilfs_set_log_cursor(struct nilfs_super_block *sbp,
251 struct the_nilfs *nilfs)
253 sector_t nfreeblocks;
255 /* nilfs->ns_sem must be locked by the caller. */
256 nilfs_count_free_blocks(nilfs, &nfreeblocks);
257 sbp->s_free_blocks_count = cpu_to_le64(nfreeblocks);
259 spin_lock(&nilfs->ns_last_segment_lock);
260 sbp->s_last_seq = cpu_to_le64(nilfs->ns_last_seq);
261 sbp->s_last_pseg = cpu_to_le64(nilfs->ns_last_pseg);
262 sbp->s_last_cno = cpu_to_le64(nilfs->ns_last_cno);
263 spin_unlock(&nilfs->ns_last_segment_lock);
266 struct nilfs_super_block **nilfs_prepare_super(struct super_block *sb,
267 int flip)
269 struct the_nilfs *nilfs = sb->s_fs_info;
270 struct nilfs_super_block **sbp = nilfs->ns_sbp;
272 /* nilfs->ns_sem must be locked by the caller. */
273 if (sbp[0]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) {
274 if (sbp[1] &&
275 sbp[1]->s_magic == cpu_to_le16(NILFS_SUPER_MAGIC)) {
276 memcpy(sbp[0], sbp[1], nilfs->ns_sbsize);
277 } else {
278 printk(KERN_CRIT "NILFS: superblock broke on dev %s\n",
279 sb->s_id);
280 return NULL;
282 } else if (sbp[1] &&
283 sbp[1]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) {
284 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
287 if (flip && sbp[1])
288 nilfs_swap_super_block(nilfs);
290 return sbp;
293 int nilfs_commit_super(struct super_block *sb, int flag)
295 struct the_nilfs *nilfs = sb->s_fs_info;
296 struct nilfs_super_block **sbp = nilfs->ns_sbp;
297 time_t t;
299 /* nilfs->ns_sem must be locked by the caller. */
300 t = get_seconds();
301 nilfs->ns_sbwtime = t;
302 sbp[0]->s_wtime = cpu_to_le64(t);
303 sbp[0]->s_sum = 0;
304 sbp[0]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed,
305 (unsigned char *)sbp[0],
306 nilfs->ns_sbsize));
307 if (flag == NILFS_SB_COMMIT_ALL && sbp[1]) {
308 sbp[1]->s_wtime = sbp[0]->s_wtime;
309 sbp[1]->s_sum = 0;
310 sbp[1]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed,
311 (unsigned char *)sbp[1],
312 nilfs->ns_sbsize));
314 clear_nilfs_sb_dirty(nilfs);
315 return nilfs_sync_super(sb, flag);
319 * nilfs_cleanup_super() - write filesystem state for cleanup
320 * @sb: super block instance to be unmounted or degraded to read-only
322 * This function restores state flags in the on-disk super block.
323 * This will set "clean" flag (i.e. NILFS_VALID_FS) unless the
324 * filesystem was not clean previously.
326 int nilfs_cleanup_super(struct super_block *sb)
328 struct the_nilfs *nilfs = sb->s_fs_info;
329 struct nilfs_super_block **sbp;
330 int flag = NILFS_SB_COMMIT;
331 int ret = -EIO;
333 sbp = nilfs_prepare_super(sb, 0);
334 if (sbp) {
335 sbp[0]->s_state = cpu_to_le16(nilfs->ns_mount_state);
336 nilfs_set_log_cursor(sbp[0], nilfs);
337 if (sbp[1] && sbp[0]->s_last_cno == sbp[1]->s_last_cno) {
339 * make the "clean" flag also to the opposite
340 * super block if both super blocks point to
341 * the same checkpoint.
343 sbp[1]->s_state = sbp[0]->s_state;
344 flag = NILFS_SB_COMMIT_ALL;
346 ret = nilfs_commit_super(sb, flag);
348 return ret;
352 * nilfs_move_2nd_super - relocate secondary super block
353 * @sb: super block instance
354 * @sb2off: new offset of the secondary super block (in bytes)
356 static int nilfs_move_2nd_super(struct super_block *sb, loff_t sb2off)
358 struct the_nilfs *nilfs = sb->s_fs_info;
359 struct buffer_head *nsbh;
360 struct nilfs_super_block *nsbp;
361 sector_t blocknr, newblocknr;
362 unsigned long offset;
363 int sb2i = -1; /* array index of the secondary superblock */
364 int ret = 0;
366 /* nilfs->ns_sem must be locked by the caller. */
367 if (nilfs->ns_sbh[1] &&
368 nilfs->ns_sbh[1]->b_blocknr > nilfs->ns_first_data_block) {
369 sb2i = 1;
370 blocknr = nilfs->ns_sbh[1]->b_blocknr;
371 } else if (nilfs->ns_sbh[0]->b_blocknr > nilfs->ns_first_data_block) {
372 sb2i = 0;
373 blocknr = nilfs->ns_sbh[0]->b_blocknr;
375 if (sb2i >= 0 && (u64)blocknr << nilfs->ns_blocksize_bits == sb2off)
376 goto out; /* super block location is unchanged */
378 /* Get new super block buffer */
379 newblocknr = sb2off >> nilfs->ns_blocksize_bits;
380 offset = sb2off & (nilfs->ns_blocksize - 1);
381 nsbh = sb_getblk(sb, newblocknr);
382 if (!nsbh) {
383 printk(KERN_WARNING
384 "NILFS warning: unable to move secondary superblock "
385 "to block %llu\n", (unsigned long long)newblocknr);
386 ret = -EIO;
387 goto out;
389 nsbp = (void *)nsbh->b_data + offset;
390 memset(nsbp, 0, nilfs->ns_blocksize);
392 if (sb2i >= 0) {
393 memcpy(nsbp, nilfs->ns_sbp[sb2i], nilfs->ns_sbsize);
394 brelse(nilfs->ns_sbh[sb2i]);
395 nilfs->ns_sbh[sb2i] = nsbh;
396 nilfs->ns_sbp[sb2i] = nsbp;
397 } else if (nilfs->ns_sbh[0]->b_blocknr < nilfs->ns_first_data_block) {
398 /* secondary super block will be restored to index 1 */
399 nilfs->ns_sbh[1] = nsbh;
400 nilfs->ns_sbp[1] = nsbp;
401 } else {
402 brelse(nsbh);
404 out:
405 return ret;
409 * nilfs_resize_fs - resize the filesystem
410 * @sb: super block instance
411 * @newsize: new size of the filesystem (in bytes)
413 int nilfs_resize_fs(struct super_block *sb, __u64 newsize)
415 struct the_nilfs *nilfs = sb->s_fs_info;
416 struct nilfs_super_block **sbp;
417 __u64 devsize, newnsegs;
418 loff_t sb2off;
419 int ret;
421 ret = -ERANGE;
422 devsize = i_size_read(sb->s_bdev->bd_inode);
423 if (newsize > devsize)
424 goto out;
427 * Write lock is required to protect some functions depending
428 * on the number of segments, the number of reserved segments,
429 * and so forth.
431 down_write(&nilfs->ns_segctor_sem);
433 sb2off = NILFS_SB2_OFFSET_BYTES(newsize);
434 newnsegs = sb2off >> nilfs->ns_blocksize_bits;
435 do_div(newnsegs, nilfs->ns_blocks_per_segment);
437 ret = nilfs_sufile_resize(nilfs->ns_sufile, newnsegs);
438 up_write(&nilfs->ns_segctor_sem);
439 if (ret < 0)
440 goto out;
442 ret = nilfs_construct_segment(sb);
443 if (ret < 0)
444 goto out;
446 down_write(&nilfs->ns_sem);
447 nilfs_move_2nd_super(sb, sb2off);
448 ret = -EIO;
449 sbp = nilfs_prepare_super(sb, 0);
450 if (likely(sbp)) {
451 nilfs_set_log_cursor(sbp[0], nilfs);
453 * Drop NILFS_RESIZE_FS flag for compatibility with
454 * mount-time resize which may be implemented in a
455 * future release.
457 sbp[0]->s_state = cpu_to_le16(le16_to_cpu(sbp[0]->s_state) &
458 ~NILFS_RESIZE_FS);
459 sbp[0]->s_dev_size = cpu_to_le64(newsize);
460 sbp[0]->s_nsegments = cpu_to_le64(nilfs->ns_nsegments);
461 if (sbp[1])
462 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
463 ret = nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL);
465 up_write(&nilfs->ns_sem);
468 * Reset the range of allocatable segments last. This order
469 * is important in the case of expansion because the secondary
470 * superblock must be protected from log write until migration
471 * completes.
473 if (!ret)
474 nilfs_sufile_set_alloc_range(nilfs->ns_sufile, 0, newnsegs - 1);
475 out:
476 return ret;
479 static void nilfs_put_super(struct super_block *sb)
481 struct the_nilfs *nilfs = sb->s_fs_info;
483 nilfs_detach_log_writer(sb);
485 if (!(sb->s_flags & MS_RDONLY)) {
486 down_write(&nilfs->ns_sem);
487 nilfs_cleanup_super(sb);
488 up_write(&nilfs->ns_sem);
491 iput(nilfs->ns_sufile);
492 iput(nilfs->ns_cpfile);
493 iput(nilfs->ns_dat);
495 destroy_nilfs(nilfs);
496 sb->s_fs_info = NULL;
499 static int nilfs_sync_fs(struct super_block *sb, int wait)
501 struct the_nilfs *nilfs = sb->s_fs_info;
502 struct nilfs_super_block **sbp;
503 int err = 0;
505 /* This function is called when super block should be written back */
506 if (wait)
507 err = nilfs_construct_segment(sb);
509 down_write(&nilfs->ns_sem);
510 if (nilfs_sb_dirty(nilfs)) {
511 sbp = nilfs_prepare_super(sb, nilfs_sb_will_flip(nilfs));
512 if (likely(sbp)) {
513 nilfs_set_log_cursor(sbp[0], nilfs);
514 nilfs_commit_super(sb, NILFS_SB_COMMIT);
517 up_write(&nilfs->ns_sem);
519 return err;
522 int nilfs_attach_checkpoint(struct super_block *sb, __u64 cno, int curr_mnt,
523 struct nilfs_root **rootp)
525 struct the_nilfs *nilfs = sb->s_fs_info;
526 struct nilfs_root *root;
527 struct nilfs_checkpoint *raw_cp;
528 struct buffer_head *bh_cp;
529 int err = -ENOMEM;
531 root = nilfs_find_or_create_root(
532 nilfs, curr_mnt ? NILFS_CPTREE_CURRENT_CNO : cno);
533 if (!root)
534 return err;
536 if (root->ifile)
537 goto reuse; /* already attached checkpoint */
539 down_read(&nilfs->ns_segctor_sem);
540 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, cno, 0, &raw_cp,
541 &bh_cp);
542 up_read(&nilfs->ns_segctor_sem);
543 if (unlikely(err)) {
544 if (err == -ENOENT || err == -EINVAL) {
545 printk(KERN_ERR
546 "NILFS: Invalid checkpoint "
547 "(checkpoint number=%llu)\n",
548 (unsigned long long)cno);
549 err = -EINVAL;
551 goto failed;
554 err = nilfs_ifile_read(sb, root, nilfs->ns_inode_size,
555 &raw_cp->cp_ifile_inode, &root->ifile);
556 if (err)
557 goto failed_bh;
559 atomic_set(&root->inodes_count, le64_to_cpu(raw_cp->cp_inodes_count));
560 atomic_set(&root->blocks_count, le64_to_cpu(raw_cp->cp_blocks_count));
562 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp);
564 reuse:
565 *rootp = root;
566 return 0;
568 failed_bh:
569 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp);
570 failed:
571 nilfs_put_root(root);
573 return err;
576 static int nilfs_freeze(struct super_block *sb)
578 struct the_nilfs *nilfs = sb->s_fs_info;
579 int err;
581 if (sb->s_flags & MS_RDONLY)
582 return 0;
584 /* Mark super block clean */
585 down_write(&nilfs->ns_sem);
586 err = nilfs_cleanup_super(sb);
587 up_write(&nilfs->ns_sem);
588 return err;
591 static int nilfs_unfreeze(struct super_block *sb)
593 struct the_nilfs *nilfs = sb->s_fs_info;
595 if (sb->s_flags & MS_RDONLY)
596 return 0;
598 down_write(&nilfs->ns_sem);
599 nilfs_setup_super(sb, false);
600 up_write(&nilfs->ns_sem);
601 return 0;
604 static int nilfs_statfs(struct dentry *dentry, struct kstatfs *buf)
606 struct super_block *sb = dentry->d_sb;
607 struct nilfs_root *root = NILFS_I(dentry->d_inode)->i_root;
608 struct the_nilfs *nilfs = root->nilfs;
609 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
610 unsigned long long blocks;
611 unsigned long overhead;
612 unsigned long nrsvblocks;
613 sector_t nfreeblocks;
614 int err;
617 * Compute all of the segment blocks
619 * The blocks before first segment and after last segment
620 * are excluded.
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;
627 * Compute the overhead
629 * When distributing meta data blocks outside segment structure,
630 * We must count them as the overhead.
632 overhead = 0;
634 err = nilfs_count_free_blocks(nilfs, &nfreeblocks);
635 if (unlikely(err))
636 return err;
638 buf->f_type = NILFS_SUPER_MAGIC;
639 buf->f_bsize = sb->s_blocksize;
640 buf->f_blocks = blocks - overhead;
641 buf->f_bfree = nfreeblocks;
642 buf->f_bavail = (buf->f_bfree >= nrsvblocks) ?
643 (buf->f_bfree - nrsvblocks) : 0;
644 buf->f_files = atomic_read(&root->inodes_count);
645 buf->f_ffree = 0; /* nilfs_count_free_inodes(sb); */
646 buf->f_namelen = NILFS_NAME_LEN;
647 buf->f_fsid.val[0] = (u32)id;
648 buf->f_fsid.val[1] = (u32)(id >> 32);
650 return 0;
653 static int nilfs_show_options(struct seq_file *seq, struct vfsmount *vfs)
655 struct super_block *sb = vfs->mnt_sb;
656 struct the_nilfs *nilfs = sb->s_fs_info;
657 struct nilfs_root *root = NILFS_I(vfs->mnt_root->d_inode)->i_root;
659 if (!nilfs_test_opt(nilfs, BARRIER))
660 seq_puts(seq, ",nobarrier");
661 if (root->cno != NILFS_CPTREE_CURRENT_CNO)
662 seq_printf(seq, ",cp=%llu", (unsigned long long)root->cno);
663 if (nilfs_test_opt(nilfs, ERRORS_PANIC))
664 seq_puts(seq, ",errors=panic");
665 if (nilfs_test_opt(nilfs, ERRORS_CONT))
666 seq_puts(seq, ",errors=continue");
667 if (nilfs_test_opt(nilfs, STRICT_ORDER))
668 seq_puts(seq, ",order=strict");
669 if (nilfs_test_opt(nilfs, NORECOVERY))
670 seq_puts(seq, ",norecovery");
671 if (nilfs_test_opt(nilfs, DISCARD))
672 seq_puts(seq, ",discard");
674 return 0;
677 static const struct super_operations nilfs_sops = {
678 .alloc_inode = nilfs_alloc_inode,
679 .destroy_inode = nilfs_destroy_inode,
680 .dirty_inode = nilfs_dirty_inode,
681 /* .write_inode = nilfs_write_inode, */
682 /* .put_inode = nilfs_put_inode, */
683 /* .drop_inode = nilfs_drop_inode, */
684 .evict_inode = nilfs_evict_inode,
685 .put_super = nilfs_put_super,
686 /* .write_super = nilfs_write_super, */
687 .sync_fs = nilfs_sync_fs,
688 .freeze_fs = nilfs_freeze,
689 .unfreeze_fs = nilfs_unfreeze,
690 /* .write_super_lockfs */
691 /* .unlockfs */
692 .statfs = nilfs_statfs,
693 .remount_fs = nilfs_remount,
694 /* .umount_begin */
695 .show_options = nilfs_show_options
698 enum {
699 Opt_err_cont, Opt_err_panic, Opt_err_ro,
700 Opt_barrier, Opt_nobarrier, Opt_snapshot, Opt_order, Opt_norecovery,
701 Opt_discard, Opt_nodiscard, Opt_err,
704 static match_table_t tokens = {
705 {Opt_err_cont, "errors=continue"},
706 {Opt_err_panic, "errors=panic"},
707 {Opt_err_ro, "errors=remount-ro"},
708 {Opt_barrier, "barrier"},
709 {Opt_nobarrier, "nobarrier"},
710 {Opt_snapshot, "cp=%u"},
711 {Opt_order, "order=%s"},
712 {Opt_norecovery, "norecovery"},
713 {Opt_discard, "discard"},
714 {Opt_nodiscard, "nodiscard"},
715 {Opt_err, NULL}
718 static int parse_options(char *options, struct super_block *sb, int is_remount)
720 struct the_nilfs *nilfs = sb->s_fs_info;
721 char *p;
722 substring_t args[MAX_OPT_ARGS];
724 if (!options)
725 return 1;
727 while ((p = strsep(&options, ",")) != NULL) {
728 int token;
729 if (!*p)
730 continue;
732 token = match_token(p, tokens, args);
733 switch (token) {
734 case Opt_barrier:
735 nilfs_set_opt(nilfs, BARRIER);
736 break;
737 case Opt_nobarrier:
738 nilfs_clear_opt(nilfs, BARRIER);
739 break;
740 case Opt_order:
741 if (strcmp(args[0].from, "relaxed") == 0)
742 /* Ordered data semantics */
743 nilfs_clear_opt(nilfs, STRICT_ORDER);
744 else if (strcmp(args[0].from, "strict") == 0)
745 /* Strict in-order semantics */
746 nilfs_set_opt(nilfs, STRICT_ORDER);
747 else
748 return 0;
749 break;
750 case Opt_err_panic:
751 nilfs_write_opt(nilfs, ERROR_MODE, ERRORS_PANIC);
752 break;
753 case Opt_err_ro:
754 nilfs_write_opt(nilfs, ERROR_MODE, ERRORS_RO);
755 break;
756 case Opt_err_cont:
757 nilfs_write_opt(nilfs, ERROR_MODE, ERRORS_CONT);
758 break;
759 case Opt_snapshot:
760 if (is_remount) {
761 printk(KERN_ERR
762 "NILFS: \"%s\" option is invalid "
763 "for remount.\n", p);
764 return 0;
766 break;
767 case Opt_norecovery:
768 nilfs_set_opt(nilfs, NORECOVERY);
769 break;
770 case Opt_discard:
771 nilfs_set_opt(nilfs, DISCARD);
772 break;
773 case Opt_nodiscard:
774 nilfs_clear_opt(nilfs, DISCARD);
775 break;
776 default:
777 printk(KERN_ERR
778 "NILFS: Unrecognized mount option \"%s\"\n", p);
779 return 0;
782 return 1;
785 static inline void
786 nilfs_set_default_options(struct super_block *sb,
787 struct nilfs_super_block *sbp)
789 struct the_nilfs *nilfs = sb->s_fs_info;
791 nilfs->ns_mount_opt =
792 NILFS_MOUNT_ERRORS_RO | NILFS_MOUNT_BARRIER;
795 static int nilfs_setup_super(struct super_block *sb, int is_mount)
797 struct the_nilfs *nilfs = sb->s_fs_info;
798 struct nilfs_super_block **sbp;
799 int max_mnt_count;
800 int mnt_count;
802 /* nilfs->ns_sem must be locked by the caller. */
803 sbp = nilfs_prepare_super(sb, 0);
804 if (!sbp)
805 return -EIO;
807 if (!is_mount)
808 goto skip_mount_setup;
810 max_mnt_count = le16_to_cpu(sbp[0]->s_max_mnt_count);
811 mnt_count = le16_to_cpu(sbp[0]->s_mnt_count);
813 if (nilfs->ns_mount_state & NILFS_ERROR_FS) {
814 printk(KERN_WARNING
815 "NILFS warning: mounting fs with errors\n");
816 #if 0
817 } else if (max_mnt_count >= 0 && mnt_count >= max_mnt_count) {
818 printk(KERN_WARNING
819 "NILFS warning: maximal mount count reached\n");
820 #endif
822 if (!max_mnt_count)
823 sbp[0]->s_max_mnt_count = cpu_to_le16(NILFS_DFL_MAX_MNT_COUNT);
825 sbp[0]->s_mnt_count = cpu_to_le16(mnt_count + 1);
826 sbp[0]->s_mtime = cpu_to_le64(get_seconds());
828 skip_mount_setup:
829 sbp[0]->s_state =
830 cpu_to_le16(le16_to_cpu(sbp[0]->s_state) & ~NILFS_VALID_FS);
831 /* synchronize sbp[1] with sbp[0] */
832 if (sbp[1])
833 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
834 return nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL);
837 struct nilfs_super_block *nilfs_read_super_block(struct super_block *sb,
838 u64 pos, int blocksize,
839 struct buffer_head **pbh)
841 unsigned long long sb_index = pos;
842 unsigned long offset;
844 offset = do_div(sb_index, blocksize);
845 *pbh = sb_bread(sb, sb_index);
846 if (!*pbh)
847 return NULL;
848 return (struct nilfs_super_block *)((char *)(*pbh)->b_data + offset);
851 int nilfs_store_magic_and_option(struct super_block *sb,
852 struct nilfs_super_block *sbp,
853 char *data)
855 struct the_nilfs *nilfs = sb->s_fs_info;
857 sb->s_magic = le16_to_cpu(sbp->s_magic);
859 /* FS independent flags */
860 #ifdef NILFS_ATIME_DISABLE
861 sb->s_flags |= MS_NOATIME;
862 #endif
864 nilfs_set_default_options(sb, sbp);
866 nilfs->ns_resuid = le16_to_cpu(sbp->s_def_resuid);
867 nilfs->ns_resgid = le16_to_cpu(sbp->s_def_resgid);
868 nilfs->ns_interval = le32_to_cpu(sbp->s_c_interval);
869 nilfs->ns_watermark = le32_to_cpu(sbp->s_c_block_max);
871 return !parse_options(data, sb, 0) ? -EINVAL : 0 ;
874 int nilfs_check_feature_compatibility(struct super_block *sb,
875 struct nilfs_super_block *sbp)
877 __u64 features;
879 features = le64_to_cpu(sbp->s_feature_incompat) &
880 ~NILFS_FEATURE_INCOMPAT_SUPP;
881 if (features) {
882 printk(KERN_ERR "NILFS: couldn't mount because of unsupported "
883 "optional features (%llx)\n",
884 (unsigned long long)features);
885 return -EINVAL;
887 features = le64_to_cpu(sbp->s_feature_compat_ro) &
888 ~NILFS_FEATURE_COMPAT_RO_SUPP;
889 if (!(sb->s_flags & MS_RDONLY) && features) {
890 printk(KERN_ERR "NILFS: couldn't mount RDWR because of "
891 "unsupported optional features (%llx)\n",
892 (unsigned long long)features);
893 return -EINVAL;
895 return 0;
898 static int nilfs_get_root_dentry(struct super_block *sb,
899 struct nilfs_root *root,
900 struct dentry **root_dentry)
902 struct inode *inode;
903 struct dentry *dentry;
904 int ret = 0;
906 inode = nilfs_iget(sb, root, NILFS_ROOT_INO);
907 if (IS_ERR(inode)) {
908 printk(KERN_ERR "NILFS: get root inode failed\n");
909 ret = PTR_ERR(inode);
910 goto out;
912 if (!S_ISDIR(inode->i_mode) || !inode->i_blocks || !inode->i_size) {
913 iput(inode);
914 printk(KERN_ERR "NILFS: corrupt root inode.\n");
915 ret = -EINVAL;
916 goto out;
919 if (root->cno == NILFS_CPTREE_CURRENT_CNO) {
920 dentry = d_find_alias(inode);
921 if (!dentry) {
922 dentry = d_alloc_root(inode);
923 if (!dentry) {
924 iput(inode);
925 ret = -ENOMEM;
926 goto failed_dentry;
928 } else {
929 iput(inode);
931 } else {
932 dentry = d_obtain_alias(inode);
933 if (IS_ERR(dentry)) {
934 ret = PTR_ERR(dentry);
935 goto failed_dentry;
938 *root_dentry = dentry;
939 out:
940 return ret;
942 failed_dentry:
943 printk(KERN_ERR "NILFS: get root dentry failed\n");
944 goto out;
947 static int nilfs_attach_snapshot(struct super_block *s, __u64 cno,
948 struct dentry **root_dentry)
950 struct the_nilfs *nilfs = s->s_fs_info;
951 struct nilfs_root *root;
952 int ret;
954 down_read(&nilfs->ns_segctor_sem);
955 ret = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile, cno);
956 up_read(&nilfs->ns_segctor_sem);
957 if (ret < 0) {
958 ret = (ret == -ENOENT) ? -EINVAL : ret;
959 goto out;
960 } else if (!ret) {
961 printk(KERN_ERR "NILFS: The specified checkpoint is "
962 "not a snapshot (checkpoint number=%llu).\n",
963 (unsigned long long)cno);
964 ret = -EINVAL;
965 goto out;
968 ret = nilfs_attach_checkpoint(s, cno, false, &root);
969 if (ret) {
970 printk(KERN_ERR "NILFS: error loading snapshot "
971 "(checkpoint number=%llu).\n",
972 (unsigned long long)cno);
973 goto out;
975 ret = nilfs_get_root_dentry(s, root, root_dentry);
976 nilfs_put_root(root);
977 out:
978 return ret;
981 static int nilfs_tree_was_touched(struct dentry *root_dentry)
983 return root_dentry->d_count > 1;
987 * nilfs_try_to_shrink_tree() - try to shrink dentries of a checkpoint
988 * @root_dentry: root dentry of the tree to be shrunk
990 * This function returns true if the tree was in-use.
992 static int nilfs_try_to_shrink_tree(struct dentry *root_dentry)
994 if (have_submounts(root_dentry))
995 return true;
996 shrink_dcache_parent(root_dentry);
997 return nilfs_tree_was_touched(root_dentry);
1000 int nilfs_checkpoint_is_mounted(struct super_block *sb, __u64 cno)
1002 struct the_nilfs *nilfs = sb->s_fs_info;
1003 struct nilfs_root *root;
1004 struct inode *inode;
1005 struct dentry *dentry;
1006 int ret;
1008 if (cno < 0 || cno > nilfs->ns_cno)
1009 return false;
1011 if (cno >= nilfs_last_cno(nilfs))
1012 return true; /* protect recent checkpoints */
1014 ret = false;
1015 root = nilfs_lookup_root(nilfs, cno);
1016 if (root) {
1017 inode = nilfs_ilookup(sb, root, NILFS_ROOT_INO);
1018 if (inode) {
1019 dentry = d_find_alias(inode);
1020 if (dentry) {
1021 if (nilfs_tree_was_touched(dentry))
1022 ret = nilfs_try_to_shrink_tree(dentry);
1023 dput(dentry);
1025 iput(inode);
1027 nilfs_put_root(root);
1029 return ret;
1033 * nilfs_fill_super() - initialize a super block instance
1034 * @sb: super_block
1035 * @data: mount options
1036 * @silent: silent mode flag
1038 * This function is called exclusively by nilfs->ns_mount_mutex.
1039 * So, the recovery process is protected from other simultaneous mounts.
1041 static int
1042 nilfs_fill_super(struct super_block *sb, void *data, int silent)
1044 struct the_nilfs *nilfs;
1045 struct nilfs_root *fsroot;
1046 struct backing_dev_info *bdi;
1047 __u64 cno;
1048 int err;
1050 nilfs = alloc_nilfs(sb->s_bdev);
1051 if (!nilfs)
1052 return -ENOMEM;
1054 sb->s_fs_info = nilfs;
1056 err = init_nilfs(nilfs, sb, (char *)data);
1057 if (err)
1058 goto failed_nilfs;
1060 sb->s_op = &nilfs_sops;
1061 sb->s_export_op = &nilfs_export_ops;
1062 sb->s_root = NULL;
1063 sb->s_time_gran = 1;
1065 bdi = sb->s_bdev->bd_inode->i_mapping->backing_dev_info;
1066 sb->s_bdi = bdi ? : &default_backing_dev_info;
1068 err = load_nilfs(nilfs, sb);
1069 if (err)
1070 goto failed_nilfs;
1072 cno = nilfs_last_cno(nilfs);
1073 err = nilfs_attach_checkpoint(sb, cno, true, &fsroot);
1074 if (err) {
1075 printk(KERN_ERR "NILFS: error loading last checkpoint "
1076 "(checkpoint number=%llu).\n", (unsigned long long)cno);
1077 goto failed_unload;
1080 if (!(sb->s_flags & MS_RDONLY)) {
1081 err = nilfs_attach_log_writer(sb, fsroot);
1082 if (err)
1083 goto failed_checkpoint;
1086 err = nilfs_get_root_dentry(sb, fsroot, &sb->s_root);
1087 if (err)
1088 goto failed_segctor;
1090 nilfs_put_root(fsroot);
1092 if (!(sb->s_flags & MS_RDONLY)) {
1093 down_write(&nilfs->ns_sem);
1094 nilfs_setup_super(sb, true);
1095 up_write(&nilfs->ns_sem);
1098 return 0;
1100 failed_segctor:
1101 nilfs_detach_log_writer(sb);
1103 failed_checkpoint:
1104 nilfs_put_root(fsroot);
1106 failed_unload:
1107 iput(nilfs->ns_sufile);
1108 iput(nilfs->ns_cpfile);
1109 iput(nilfs->ns_dat);
1111 failed_nilfs:
1112 destroy_nilfs(nilfs);
1113 return err;
1116 static int nilfs_remount(struct super_block *sb, int *flags, char *data)
1118 struct the_nilfs *nilfs = sb->s_fs_info;
1119 unsigned long old_sb_flags;
1120 unsigned long old_mount_opt;
1121 int err;
1123 old_sb_flags = sb->s_flags;
1124 old_mount_opt = nilfs->ns_mount_opt;
1126 if (!parse_options(data, sb, 1)) {
1127 err = -EINVAL;
1128 goto restore_opts;
1130 sb->s_flags = (sb->s_flags & ~MS_POSIXACL);
1132 err = -EINVAL;
1134 if (!nilfs_valid_fs(nilfs)) {
1135 printk(KERN_WARNING "NILFS (device %s): couldn't "
1136 "remount because the filesystem is in an "
1137 "incomplete recovery state.\n", sb->s_id);
1138 goto restore_opts;
1141 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
1142 goto out;
1143 if (*flags & MS_RDONLY) {
1144 /* Shutting down log writer */
1145 nilfs_detach_log_writer(sb);
1146 sb->s_flags |= MS_RDONLY;
1149 * Remounting a valid RW partition RDONLY, so set
1150 * the RDONLY flag and then mark the partition as valid again.
1152 down_write(&nilfs->ns_sem);
1153 nilfs_cleanup_super(sb);
1154 up_write(&nilfs->ns_sem);
1155 } else {
1156 __u64 features;
1157 struct nilfs_root *root;
1160 * Mounting a RDONLY partition read-write, so reread and
1161 * store the current valid flag. (It may have been changed
1162 * by fsck since we originally mounted the partition.)
1164 down_read(&nilfs->ns_sem);
1165 features = le64_to_cpu(nilfs->ns_sbp[0]->s_feature_compat_ro) &
1166 ~NILFS_FEATURE_COMPAT_RO_SUPP;
1167 up_read(&nilfs->ns_sem);
1168 if (features) {
1169 printk(KERN_WARNING "NILFS (device %s): couldn't "
1170 "remount RDWR because of unsupported optional "
1171 "features (%llx)\n",
1172 sb->s_id, (unsigned long long)features);
1173 err = -EROFS;
1174 goto restore_opts;
1177 sb->s_flags &= ~MS_RDONLY;
1179 root = NILFS_I(sb->s_root->d_inode)->i_root;
1180 err = nilfs_attach_log_writer(sb, root);
1181 if (err)
1182 goto restore_opts;
1184 down_write(&nilfs->ns_sem);
1185 nilfs_setup_super(sb, true);
1186 up_write(&nilfs->ns_sem);
1188 out:
1189 return 0;
1191 restore_opts:
1192 sb->s_flags = old_sb_flags;
1193 nilfs->ns_mount_opt = old_mount_opt;
1194 return err;
1197 struct nilfs_super_data {
1198 struct block_device *bdev;
1199 __u64 cno;
1200 int flags;
1204 * nilfs_identify - pre-read mount options needed to identify mount instance
1205 * @data: mount options
1206 * @sd: nilfs_super_data
1208 static int nilfs_identify(char *data, struct nilfs_super_data *sd)
1210 char *p, *options = data;
1211 substring_t args[MAX_OPT_ARGS];
1212 int token;
1213 int ret = 0;
1215 do {
1216 p = strsep(&options, ",");
1217 if (p != NULL && *p) {
1218 token = match_token(p, tokens, args);
1219 if (token == Opt_snapshot) {
1220 if (!(sd->flags & MS_RDONLY)) {
1221 ret++;
1222 } else {
1223 sd->cno = simple_strtoull(args[0].from,
1224 NULL, 0);
1226 * No need to see the end pointer;
1227 * match_token() has done syntax
1228 * checking.
1230 if (sd->cno == 0)
1231 ret++;
1234 if (ret)
1235 printk(KERN_ERR
1236 "NILFS: invalid mount option: %s\n", p);
1238 if (!options)
1239 break;
1240 BUG_ON(options == data);
1241 *(options - 1) = ',';
1242 } while (!ret);
1243 return ret;
1246 static int nilfs_set_bdev_super(struct super_block *s, void *data)
1248 s->s_bdev = data;
1249 s->s_dev = s->s_bdev->bd_dev;
1250 return 0;
1253 static int nilfs_test_bdev_super(struct super_block *s, void *data)
1255 return (void *)s->s_bdev == data;
1258 static struct dentry *
1259 nilfs_mount(struct file_system_type *fs_type, int flags,
1260 const char *dev_name, void *data)
1262 struct nilfs_super_data sd;
1263 struct super_block *s;
1264 fmode_t mode = FMODE_READ | FMODE_EXCL;
1265 struct dentry *root_dentry;
1266 int err, s_new = false;
1268 if (!(flags & MS_RDONLY))
1269 mode |= FMODE_WRITE;
1271 sd.bdev = blkdev_get_by_path(dev_name, mode, fs_type);
1272 if (IS_ERR(sd.bdev))
1273 return ERR_CAST(sd.bdev);
1275 sd.cno = 0;
1276 sd.flags = flags;
1277 if (nilfs_identify((char *)data, &sd)) {
1278 err = -EINVAL;
1279 goto failed;
1283 * once the super is inserted into the list by sget, s_umount
1284 * will protect the lockfs code from trying to start a snapshot
1285 * while we are mounting
1287 mutex_lock(&sd.bdev->bd_fsfreeze_mutex);
1288 if (sd.bdev->bd_fsfreeze_count > 0) {
1289 mutex_unlock(&sd.bdev->bd_fsfreeze_mutex);
1290 err = -EBUSY;
1291 goto failed;
1293 s = sget(fs_type, nilfs_test_bdev_super, nilfs_set_bdev_super, sd.bdev);
1294 mutex_unlock(&sd.bdev->bd_fsfreeze_mutex);
1295 if (IS_ERR(s)) {
1296 err = PTR_ERR(s);
1297 goto failed;
1300 if (!s->s_root) {
1301 char b[BDEVNAME_SIZE];
1303 s_new = true;
1305 /* New superblock instance created */
1306 s->s_flags = flags;
1307 s->s_mode = mode;
1308 strlcpy(s->s_id, bdevname(sd.bdev, b), sizeof(s->s_id));
1309 sb_set_blocksize(s, block_size(sd.bdev));
1311 err = nilfs_fill_super(s, data, flags & MS_SILENT ? 1 : 0);
1312 if (err)
1313 goto failed_super;
1315 s->s_flags |= MS_ACTIVE;
1316 } else if (!sd.cno) {
1317 int busy = false;
1319 if (nilfs_tree_was_touched(s->s_root)) {
1320 busy = nilfs_try_to_shrink_tree(s->s_root);
1321 if (busy && (flags ^ s->s_flags) & MS_RDONLY) {
1322 printk(KERN_ERR "NILFS: the device already "
1323 "has a %s mount.\n",
1324 (s->s_flags & MS_RDONLY) ?
1325 "read-only" : "read/write");
1326 err = -EBUSY;
1327 goto failed_super;
1330 if (!busy) {
1332 * Try remount to setup mount states if the current
1333 * tree is not mounted and only snapshots use this sb.
1335 err = nilfs_remount(s, &flags, data);
1336 if (err)
1337 goto failed_super;
1341 if (sd.cno) {
1342 err = nilfs_attach_snapshot(s, sd.cno, &root_dentry);
1343 if (err)
1344 goto failed_super;
1345 } else {
1346 root_dentry = dget(s->s_root);
1349 if (!s_new)
1350 blkdev_put(sd.bdev, mode);
1352 return root_dentry;
1354 failed_super:
1355 deactivate_locked_super(s);
1357 failed:
1358 if (!s_new)
1359 blkdev_put(sd.bdev, mode);
1360 return ERR_PTR(err);
1363 struct file_system_type nilfs_fs_type = {
1364 .owner = THIS_MODULE,
1365 .name = "nilfs2",
1366 .mount = nilfs_mount,
1367 .kill_sb = kill_block_super,
1368 .fs_flags = FS_REQUIRES_DEV,
1371 static void nilfs_inode_init_once(void *obj)
1373 struct nilfs_inode_info *ii = obj;
1375 INIT_LIST_HEAD(&ii->i_dirty);
1376 #ifdef CONFIG_NILFS_XATTR
1377 init_rwsem(&ii->xattr_sem);
1378 #endif
1379 address_space_init_once(&ii->i_btnode_cache);
1380 ii->i_bmap = &ii->i_bmap_data;
1381 inode_init_once(&ii->vfs_inode);
1384 static void nilfs_segbuf_init_once(void *obj)
1386 memset(obj, 0, sizeof(struct nilfs_segment_buffer));
1389 static void nilfs_destroy_cachep(void)
1391 if (nilfs_inode_cachep)
1392 kmem_cache_destroy(nilfs_inode_cachep);
1393 if (nilfs_transaction_cachep)
1394 kmem_cache_destroy(nilfs_transaction_cachep);
1395 if (nilfs_segbuf_cachep)
1396 kmem_cache_destroy(nilfs_segbuf_cachep);
1397 if (nilfs_btree_path_cache)
1398 kmem_cache_destroy(nilfs_btree_path_cache);
1401 static int __init nilfs_init_cachep(void)
1403 nilfs_inode_cachep = kmem_cache_create("nilfs2_inode_cache",
1404 sizeof(struct nilfs_inode_info), 0,
1405 SLAB_RECLAIM_ACCOUNT, nilfs_inode_init_once);
1406 if (!nilfs_inode_cachep)
1407 goto fail;
1409 nilfs_transaction_cachep = kmem_cache_create("nilfs2_transaction_cache",
1410 sizeof(struct nilfs_transaction_info), 0,
1411 SLAB_RECLAIM_ACCOUNT, NULL);
1412 if (!nilfs_transaction_cachep)
1413 goto fail;
1415 nilfs_segbuf_cachep = kmem_cache_create("nilfs2_segbuf_cache",
1416 sizeof(struct nilfs_segment_buffer), 0,
1417 SLAB_RECLAIM_ACCOUNT, nilfs_segbuf_init_once);
1418 if (!nilfs_segbuf_cachep)
1419 goto fail;
1421 nilfs_btree_path_cache = kmem_cache_create("nilfs2_btree_path_cache",
1422 sizeof(struct nilfs_btree_path) * NILFS_BTREE_LEVEL_MAX,
1423 0, 0, NULL);
1424 if (!nilfs_btree_path_cache)
1425 goto fail;
1427 return 0;
1429 fail:
1430 nilfs_destroy_cachep();
1431 return -ENOMEM;
1434 static int __init init_nilfs_fs(void)
1436 int err;
1438 err = nilfs_init_cachep();
1439 if (err)
1440 goto fail;
1442 err = register_filesystem(&nilfs_fs_type);
1443 if (err)
1444 goto free_cachep;
1446 printk(KERN_INFO "NILFS version 2 loaded\n");
1447 return 0;
1449 free_cachep:
1450 nilfs_destroy_cachep();
1451 fail:
1452 return err;
1455 static void __exit exit_nilfs_fs(void)
1457 nilfs_destroy_cachep();
1458 unregister_filesystem(&nilfs_fs_type);
1461 module_init(init_nilfs_fs)
1462 module_exit(exit_nilfs_fs)