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)
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/random.h>
47 #include <linux/crc32.h>
48 #include <linux/smp_lock.h>
49 #include <linux/vfs.h>
50 #include <linux/writeback.h>
51 #include <linux/kobject.h>
52 #include <linux/exportfs.h>
53 #include <linux/seq_file.h>
54 #include <linux/mount.h>
67 MODULE_AUTHOR("NTT Corp.");
68 MODULE_DESCRIPTION("A New Implementation of the Log-structured Filesystem "
70 MODULE_LICENSE("GPL");
72 struct kmem_cache
*nilfs_inode_cachep
;
73 struct kmem_cache
*nilfs_transaction_cachep
;
74 struct kmem_cache
*nilfs_segbuf_cachep
;
75 struct kmem_cache
*nilfs_btree_path_cache
;
77 static int nilfs_remount(struct super_block
*sb
, int *flags
, char *data
);
79 static void nilfs_set_error(struct nilfs_sb_info
*sbi
)
81 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
82 struct nilfs_super_block
**sbp
;
84 down_write(&nilfs
->ns_sem
);
85 if (!(nilfs
->ns_mount_state
& NILFS_ERROR_FS
)) {
86 nilfs
->ns_mount_state
|= NILFS_ERROR_FS
;
87 sbp
= nilfs_prepare_super(sbi
, 0);
89 sbp
[0]->s_state
|= cpu_to_le16(NILFS_ERROR_FS
);
91 sbp
[1]->s_state
|= cpu_to_le16(NILFS_ERROR_FS
);
92 nilfs_commit_super(sbi
, NILFS_SB_COMMIT_ALL
);
95 up_write(&nilfs
->ns_sem
);
99 * nilfs_error() - report failure condition on a filesystem
101 * nilfs_error() sets an ERROR_FS flag on the superblock as well as
102 * reporting an error message. It should be called when NILFS detects
103 * incoherences or defects of meta data on disk. As for sustainable
104 * errors such as a single-shot I/O error, nilfs_warning() or the printk()
105 * function should be used instead.
107 * The segment constructor must not call this function because it can
110 void nilfs_error(struct super_block
*sb
, const char *function
,
111 const char *fmt
, ...)
113 struct nilfs_sb_info
*sbi
= NILFS_SB(sb
);
117 printk(KERN_CRIT
"NILFS error (device %s): %s: ", sb
->s_id
, function
);
122 if (!(sb
->s_flags
& MS_RDONLY
)) {
123 nilfs_set_error(sbi
);
125 if (nilfs_test_opt(sbi
, ERRORS_RO
)) {
126 printk(KERN_CRIT
"Remounting filesystem read-only\n");
127 sb
->s_flags
|= MS_RDONLY
;
131 if (nilfs_test_opt(sbi
, ERRORS_PANIC
))
132 panic("NILFS (device %s): panic forced after error\n",
136 void nilfs_warning(struct super_block
*sb
, const char *function
,
137 const char *fmt
, ...)
142 printk(KERN_WARNING
"NILFS warning (device %s): %s: ",
150 struct inode
*nilfs_alloc_inode_common(struct the_nilfs
*nilfs
)
152 struct nilfs_inode_info
*ii
;
154 ii
= kmem_cache_alloc(nilfs_inode_cachep
, GFP_NOFS
);
159 ii
->vfs_inode
.i_version
= 1;
160 nilfs_btnode_cache_init(&ii
->i_btnode_cache
, nilfs
->ns_bdi
);
161 return &ii
->vfs_inode
;
164 struct inode
*nilfs_alloc_inode(struct super_block
*sb
)
166 return nilfs_alloc_inode_common(NILFS_SB(sb
)->s_nilfs
);
169 void nilfs_destroy_inode(struct inode
*inode
)
171 kmem_cache_free(nilfs_inode_cachep
, NILFS_I(inode
));
174 static int nilfs_sync_super(struct nilfs_sb_info
*sbi
, int flag
)
176 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
180 set_buffer_dirty(nilfs
->ns_sbh
[0]);
182 if (nilfs_test_opt(sbi
, BARRIER
)) {
183 err
= __sync_dirty_buffer(nilfs
->ns_sbh
[0],
184 WRITE_SYNC
| WRITE_BARRIER
);
185 if (err
== -EOPNOTSUPP
) {
186 nilfs_warning(sbi
->s_super
, __func__
,
187 "barrier-based sync failed. "
188 "disabling barriers\n");
189 nilfs_clear_opt(sbi
, BARRIER
);
193 err
= sync_dirty_buffer(nilfs
->ns_sbh
[0]);
198 "NILFS: unable to write superblock (err=%d)\n", err
);
199 if (err
== -EIO
&& nilfs
->ns_sbh
[1]) {
201 * sbp[0] points to newer log than sbp[1],
202 * so copy sbp[0] to sbp[1] to take over sbp[0].
204 memcpy(nilfs
->ns_sbp
[1], nilfs
->ns_sbp
[0],
206 nilfs_fall_back_super_block(nilfs
);
210 struct nilfs_super_block
*sbp
= nilfs
->ns_sbp
[0];
212 nilfs
->ns_sbwcount
++;
215 * The latest segment becomes trailable from the position
216 * written in superblock.
218 clear_nilfs_discontinued(nilfs
);
220 /* update GC protection for recent segments */
221 if (nilfs
->ns_sbh
[1]) {
222 if (flag
== NILFS_SB_COMMIT_ALL
) {
223 set_buffer_dirty(nilfs
->ns_sbh
[1]);
224 if (sync_dirty_buffer(nilfs
->ns_sbh
[1]) < 0)
227 if (le64_to_cpu(nilfs
->ns_sbp
[1]->s_last_cno
) <
228 le64_to_cpu(nilfs
->ns_sbp
[0]->s_last_cno
))
229 sbp
= nilfs
->ns_sbp
[1];
232 spin_lock(&nilfs
->ns_last_segment_lock
);
233 nilfs
->ns_prot_seq
= le64_to_cpu(sbp
->s_last_seq
);
234 spin_unlock(&nilfs
->ns_last_segment_lock
);
240 void nilfs_set_log_cursor(struct nilfs_super_block
*sbp
,
241 struct the_nilfs
*nilfs
)
243 sector_t nfreeblocks
;
245 /* nilfs->ns_sem must be locked by the caller. */
246 nilfs_count_free_blocks(nilfs
, &nfreeblocks
);
247 sbp
->s_free_blocks_count
= cpu_to_le64(nfreeblocks
);
249 spin_lock(&nilfs
->ns_last_segment_lock
);
250 sbp
->s_last_seq
= cpu_to_le64(nilfs
->ns_last_seq
);
251 sbp
->s_last_pseg
= cpu_to_le64(nilfs
->ns_last_pseg
);
252 sbp
->s_last_cno
= cpu_to_le64(nilfs
->ns_last_cno
);
253 spin_unlock(&nilfs
->ns_last_segment_lock
);
256 struct nilfs_super_block
**nilfs_prepare_super(struct nilfs_sb_info
*sbi
,
259 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
260 struct nilfs_super_block
**sbp
= nilfs
->ns_sbp
;
262 /* nilfs->ns_sem must be locked by the caller. */
263 if (sbp
[0]->s_magic
!= cpu_to_le16(NILFS_SUPER_MAGIC
)) {
265 sbp
[1]->s_magic
== cpu_to_le16(NILFS_SUPER_MAGIC
)) {
266 memcpy(sbp
[0], sbp
[1], nilfs
->ns_sbsize
);
268 printk(KERN_CRIT
"NILFS: superblock broke on dev %s\n",
273 sbp
[1]->s_magic
!= cpu_to_le16(NILFS_SUPER_MAGIC
)) {
274 memcpy(sbp
[1], sbp
[0], nilfs
->ns_sbsize
);
278 nilfs_swap_super_block(nilfs
);
283 int nilfs_commit_super(struct nilfs_sb_info
*sbi
, int flag
)
285 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
286 struct nilfs_super_block
**sbp
= nilfs
->ns_sbp
;
289 /* nilfs->ns_sem must be locked by the caller. */
291 nilfs
->ns_sbwtime
= t
;
292 sbp
[0]->s_wtime
= cpu_to_le64(t
);
294 sbp
[0]->s_sum
= cpu_to_le32(crc32_le(nilfs
->ns_crc_seed
,
295 (unsigned char *)sbp
[0],
297 if (flag
== NILFS_SB_COMMIT_ALL
&& sbp
[1]) {
298 sbp
[1]->s_wtime
= sbp
[0]->s_wtime
;
300 sbp
[1]->s_sum
= cpu_to_le32(crc32_le(nilfs
->ns_crc_seed
,
301 (unsigned char *)sbp
[1],
304 clear_nilfs_sb_dirty(nilfs
);
305 return nilfs_sync_super(sbi
, flag
);
309 * nilfs_cleanup_super() - write filesystem state for cleanup
310 * @sbi: nilfs_sb_info to be unmounted or degraded to read-only
312 * This function restores state flags in the on-disk super block.
313 * This will set "clean" flag (i.e. NILFS_VALID_FS) unless the
314 * filesystem was not clean previously.
316 int nilfs_cleanup_super(struct nilfs_sb_info
*sbi
)
318 struct nilfs_super_block
**sbp
;
319 int flag
= NILFS_SB_COMMIT
;
322 sbp
= nilfs_prepare_super(sbi
, 0);
324 sbp
[0]->s_state
= cpu_to_le16(sbi
->s_nilfs
->ns_mount_state
);
325 nilfs_set_log_cursor(sbp
[0], sbi
->s_nilfs
);
326 if (sbp
[1] && sbp
[0]->s_last_cno
== sbp
[1]->s_last_cno
) {
328 * make the "clean" flag also to the opposite
329 * super block if both super blocks point to
330 * the same checkpoint.
332 sbp
[1]->s_state
= sbp
[0]->s_state
;
333 flag
= NILFS_SB_COMMIT_ALL
;
335 ret
= nilfs_commit_super(sbi
, flag
);
340 static void nilfs_put_super(struct super_block
*sb
)
342 struct nilfs_sb_info
*sbi
= NILFS_SB(sb
);
343 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
347 nilfs_detach_segment_constructor(sbi
);
349 if (!(sb
->s_flags
& MS_RDONLY
)) {
350 down_write(&nilfs
->ns_sem
);
351 nilfs_cleanup_super(sbi
);
352 up_write(&nilfs
->ns_sem
);
354 down_write(&nilfs
->ns_super_sem
);
355 if (nilfs
->ns_current
== sbi
)
356 nilfs
->ns_current
= NULL
;
357 up_write(&nilfs
->ns_super_sem
);
359 nilfs_detach_checkpoint(sbi
);
360 put_nilfs(sbi
->s_nilfs
);
362 sb
->s_fs_info
= NULL
;
363 nilfs_put_sbinfo(sbi
);
368 static int nilfs_sync_fs(struct super_block
*sb
, int wait
)
370 struct nilfs_sb_info
*sbi
= NILFS_SB(sb
);
371 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
372 struct nilfs_super_block
**sbp
;
375 /* This function is called when super block should be written back */
377 err
= nilfs_construct_segment(sb
);
379 down_write(&nilfs
->ns_sem
);
380 if (nilfs_sb_dirty(nilfs
)) {
381 sbp
= nilfs_prepare_super(sbi
, nilfs_sb_will_flip(nilfs
));
383 nilfs_set_log_cursor(sbp
[0], nilfs
);
384 nilfs_commit_super(sbi
, NILFS_SB_COMMIT
);
387 up_write(&nilfs
->ns_sem
);
392 int nilfs_attach_checkpoint(struct nilfs_sb_info
*sbi
, __u64 cno
)
394 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
395 struct nilfs_checkpoint
*raw_cp
;
396 struct buffer_head
*bh_cp
;
399 down_write(&nilfs
->ns_super_sem
);
400 list_add(&sbi
->s_list
, &nilfs
->ns_supers
);
401 up_write(&nilfs
->ns_super_sem
);
404 sbi
->s_ifile
= nilfs_ifile_new(sbi
, nilfs
->ns_inode_size
);
408 down_read(&nilfs
->ns_segctor_sem
);
409 err
= nilfs_cpfile_get_checkpoint(nilfs
->ns_cpfile
, cno
, 0, &raw_cp
,
411 up_read(&nilfs
->ns_segctor_sem
);
413 if (err
== -ENOENT
|| err
== -EINVAL
) {
415 "NILFS: Invalid checkpoint "
416 "(checkpoint number=%llu)\n",
417 (unsigned long long)cno
);
422 err
= nilfs_read_inode_common(sbi
->s_ifile
, &raw_cp
->cp_ifile_inode
);
425 atomic_set(&sbi
->s_inodes_count
, le64_to_cpu(raw_cp
->cp_inodes_count
));
426 atomic_set(&sbi
->s_blocks_count
, le64_to_cpu(raw_cp
->cp_blocks_count
));
428 nilfs_cpfile_put_checkpoint(nilfs
->ns_cpfile
, cno
, bh_cp
);
432 nilfs_cpfile_put_checkpoint(nilfs
->ns_cpfile
, cno
, bh_cp
);
434 nilfs_mdt_destroy(sbi
->s_ifile
);
438 down_write(&nilfs
->ns_super_sem
);
439 list_del_init(&sbi
->s_list
);
440 up_write(&nilfs
->ns_super_sem
);
445 void nilfs_detach_checkpoint(struct nilfs_sb_info
*sbi
)
447 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
449 nilfs_mdt_destroy(sbi
->s_ifile
);
451 down_write(&nilfs
->ns_super_sem
);
452 list_del_init(&sbi
->s_list
);
453 up_write(&nilfs
->ns_super_sem
);
456 static int nilfs_statfs(struct dentry
*dentry
, struct kstatfs
*buf
)
458 struct super_block
*sb
= dentry
->d_sb
;
459 struct nilfs_sb_info
*sbi
= NILFS_SB(sb
);
460 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
461 u64 id
= huge_encode_dev(sb
->s_bdev
->bd_dev
);
462 unsigned long long blocks
;
463 unsigned long overhead
;
464 unsigned long nrsvblocks
;
465 sector_t nfreeblocks
;
469 * Compute all of the segment blocks
471 * The blocks before first segment and after last segment
474 blocks
= nilfs
->ns_blocks_per_segment
* nilfs
->ns_nsegments
475 - nilfs
->ns_first_data_block
;
476 nrsvblocks
= nilfs
->ns_nrsvsegs
* nilfs
->ns_blocks_per_segment
;
479 * Compute the overhead
481 * When distributing meta data blocks outside segment structure,
482 * We must count them as the overhead.
486 err
= nilfs_count_free_blocks(nilfs
, &nfreeblocks
);
490 buf
->f_type
= NILFS_SUPER_MAGIC
;
491 buf
->f_bsize
= sb
->s_blocksize
;
492 buf
->f_blocks
= blocks
- overhead
;
493 buf
->f_bfree
= nfreeblocks
;
494 buf
->f_bavail
= (buf
->f_bfree
>= nrsvblocks
) ?
495 (buf
->f_bfree
- nrsvblocks
) : 0;
496 buf
->f_files
= atomic_read(&sbi
->s_inodes_count
);
497 buf
->f_ffree
= 0; /* nilfs_count_free_inodes(sb); */
498 buf
->f_namelen
= NILFS_NAME_LEN
;
499 buf
->f_fsid
.val
[0] = (u32
)id
;
500 buf
->f_fsid
.val
[1] = (u32
)(id
>> 32);
505 static int nilfs_show_options(struct seq_file
*seq
, struct vfsmount
*vfs
)
507 struct super_block
*sb
= vfs
->mnt_sb
;
508 struct nilfs_sb_info
*sbi
= NILFS_SB(sb
);
510 if (!nilfs_test_opt(sbi
, BARRIER
))
511 seq_puts(seq
, ",nobarrier");
512 if (nilfs_test_opt(sbi
, SNAPSHOT
))
513 seq_printf(seq
, ",cp=%llu",
514 (unsigned long long int)sbi
->s_snapshot_cno
);
515 if (nilfs_test_opt(sbi
, ERRORS_PANIC
))
516 seq_puts(seq
, ",errors=panic");
517 if (nilfs_test_opt(sbi
, ERRORS_CONT
))
518 seq_puts(seq
, ",errors=continue");
519 if (nilfs_test_opt(sbi
, STRICT_ORDER
))
520 seq_puts(seq
, ",order=strict");
521 if (nilfs_test_opt(sbi
, NORECOVERY
))
522 seq_puts(seq
, ",norecovery");
523 if (nilfs_test_opt(sbi
, DISCARD
))
524 seq_puts(seq
, ",discard");
529 static const struct super_operations nilfs_sops
= {
530 .alloc_inode
= nilfs_alloc_inode
,
531 .destroy_inode
= nilfs_destroy_inode
,
532 .dirty_inode
= nilfs_dirty_inode
,
533 /* .write_inode = nilfs_write_inode, */
534 /* .put_inode = nilfs_put_inode, */
535 /* .drop_inode = nilfs_drop_inode, */
536 .evict_inode
= nilfs_evict_inode
,
537 .put_super
= nilfs_put_super
,
538 /* .write_super = nilfs_write_super, */
539 .sync_fs
= nilfs_sync_fs
,
540 /* .write_super_lockfs */
542 .statfs
= nilfs_statfs
,
543 .remount_fs
= nilfs_remount
,
545 .show_options
= nilfs_show_options
548 static struct inode
*
549 nilfs_nfs_get_inode(struct super_block
*sb
, u64 ino
, u32 generation
)
553 if (ino
< NILFS_FIRST_INO(sb
) && ino
!= NILFS_ROOT_INO
&&
554 ino
!= NILFS_SKETCH_INO
)
555 return ERR_PTR(-ESTALE
);
557 inode
= nilfs_iget(sb
, ino
);
559 return ERR_CAST(inode
);
560 if (generation
&& inode
->i_generation
!= generation
) {
562 return ERR_PTR(-ESTALE
);
568 static struct dentry
*
569 nilfs_fh_to_dentry(struct super_block
*sb
, struct fid
*fid
, int fh_len
,
572 return generic_fh_to_dentry(sb
, fid
, fh_len
, fh_type
,
573 nilfs_nfs_get_inode
);
576 static struct dentry
*
577 nilfs_fh_to_parent(struct super_block
*sb
, struct fid
*fid
, int fh_len
,
580 return generic_fh_to_parent(sb
, fid
, fh_len
, fh_type
,
581 nilfs_nfs_get_inode
);
584 static const struct export_operations nilfs_export_ops
= {
585 .fh_to_dentry
= nilfs_fh_to_dentry
,
586 .fh_to_parent
= nilfs_fh_to_parent
,
587 .get_parent
= nilfs_get_parent
,
591 Opt_err_cont
, Opt_err_panic
, Opt_err_ro
,
592 Opt_barrier
, Opt_nobarrier
, Opt_snapshot
, Opt_order
, Opt_norecovery
,
593 Opt_discard
, Opt_nodiscard
, Opt_err
,
596 static match_table_t tokens
= {
597 {Opt_err_cont
, "errors=continue"},
598 {Opt_err_panic
, "errors=panic"},
599 {Opt_err_ro
, "errors=remount-ro"},
600 {Opt_barrier
, "barrier"},
601 {Opt_nobarrier
, "nobarrier"},
602 {Opt_snapshot
, "cp=%u"},
603 {Opt_order
, "order=%s"},
604 {Opt_norecovery
, "norecovery"},
605 {Opt_discard
, "discard"},
606 {Opt_nodiscard
, "nodiscard"},
610 static int parse_options(char *options
, struct super_block
*sb
, int is_remount
)
612 struct nilfs_sb_info
*sbi
= NILFS_SB(sb
);
614 substring_t args
[MAX_OPT_ARGS
];
620 while ((p
= strsep(&options
, ",")) != NULL
) {
625 token
= match_token(p
, tokens
, args
);
628 nilfs_set_opt(sbi
, BARRIER
);
631 nilfs_clear_opt(sbi
, BARRIER
);
634 if (strcmp(args
[0].from
, "relaxed") == 0)
635 /* Ordered data semantics */
636 nilfs_clear_opt(sbi
, STRICT_ORDER
);
637 else if (strcmp(args
[0].from
, "strict") == 0)
638 /* Strict in-order semantics */
639 nilfs_set_opt(sbi
, STRICT_ORDER
);
644 nilfs_write_opt(sbi
, ERROR_MODE
, ERRORS_PANIC
);
647 nilfs_write_opt(sbi
, ERROR_MODE
, ERRORS_RO
);
650 nilfs_write_opt(sbi
, ERROR_MODE
, ERRORS_CONT
);
653 if (match_int(&args
[0], &option
) || option
<= 0)
656 if (!nilfs_test_opt(sbi
, SNAPSHOT
)) {
658 "NILFS: cannot change regular "
659 "mount to snapshot.\n");
661 } else if (option
!= sbi
->s_snapshot_cno
) {
663 "NILFS: cannot remount to a "
664 "different snapshot.\n");
669 if (!(sb
->s_flags
& MS_RDONLY
)) {
670 printk(KERN_ERR
"NILFS: cannot mount snapshot "
671 "read/write. A read-only option is "
675 sbi
->s_snapshot_cno
= option
;
676 nilfs_set_opt(sbi
, SNAPSHOT
);
679 nilfs_set_opt(sbi
, NORECOVERY
);
682 nilfs_set_opt(sbi
, DISCARD
);
685 nilfs_clear_opt(sbi
, DISCARD
);
689 "NILFS: Unrecognized mount option \"%s\"\n", p
);
697 nilfs_set_default_options(struct nilfs_sb_info
*sbi
,
698 struct nilfs_super_block
*sbp
)
701 NILFS_MOUNT_ERRORS_RO
| NILFS_MOUNT_BARRIER
;
704 static int nilfs_setup_super(struct nilfs_sb_info
*sbi
)
706 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
707 struct nilfs_super_block
**sbp
;
711 /* nilfs->ns_sem must be locked by the caller. */
712 sbp
= nilfs_prepare_super(sbi
, 0);
716 max_mnt_count
= le16_to_cpu(sbp
[0]->s_max_mnt_count
);
717 mnt_count
= le16_to_cpu(sbp
[0]->s_mnt_count
);
719 if (nilfs
->ns_mount_state
& NILFS_ERROR_FS
) {
721 "NILFS warning: mounting fs with errors\n");
724 sbp
[0]->s_max_mnt_count
= cpu_to_le16(NILFS_DFL_MAX_MNT_COUNT
);
726 sbp
[0]->s_mnt_count
= cpu_to_le16(mnt_count
+ 1);
728 cpu_to_le16(le16_to_cpu(sbp
[0]->s_state
) & ~NILFS_VALID_FS
);
729 sbp
[0]->s_mtime
= cpu_to_le64(get_seconds());
730 /* synchronize sbp[1] with sbp[0] */
732 memcpy(sbp
[1], sbp
[0], nilfs
->ns_sbsize
);
733 return nilfs_commit_super(sbi
, NILFS_SB_COMMIT_ALL
);
736 struct nilfs_super_block
*nilfs_read_super_block(struct super_block
*sb
,
737 u64 pos
, int blocksize
,
738 struct buffer_head
**pbh
)
740 unsigned long long sb_index
= pos
;
741 unsigned long offset
;
743 offset
= do_div(sb_index
, blocksize
);
744 *pbh
= sb_bread(sb
, sb_index
);
747 return (struct nilfs_super_block
*)((char *)(*pbh
)->b_data
+ offset
);
750 int nilfs_store_magic_and_option(struct super_block
*sb
,
751 struct nilfs_super_block
*sbp
,
754 struct nilfs_sb_info
*sbi
= NILFS_SB(sb
);
756 sb
->s_magic
= le16_to_cpu(sbp
->s_magic
);
758 /* FS independent flags */
759 #ifdef NILFS_ATIME_DISABLE
760 sb
->s_flags
|= MS_NOATIME
;
763 nilfs_set_default_options(sbi
, sbp
);
765 sbi
->s_resuid
= le16_to_cpu(sbp
->s_def_resuid
);
766 sbi
->s_resgid
= le16_to_cpu(sbp
->s_def_resgid
);
767 sbi
->s_interval
= le32_to_cpu(sbp
->s_c_interval
);
768 sbi
->s_watermark
= le32_to_cpu(sbp
->s_c_block_max
);
770 return !parse_options(data
, sb
, 0) ? -EINVAL
: 0 ;
773 int nilfs_check_feature_compatibility(struct super_block
*sb
,
774 struct nilfs_super_block
*sbp
)
778 features
= le64_to_cpu(sbp
->s_feature_incompat
) &
779 ~NILFS_FEATURE_INCOMPAT_SUPP
;
781 printk(KERN_ERR
"NILFS: couldn't mount because of unsupported "
782 "optional features (%llx)\n",
783 (unsigned long long)features
);
786 features
= le64_to_cpu(sbp
->s_feature_compat_ro
) &
787 ~NILFS_FEATURE_COMPAT_RO_SUPP
;
788 if (!(sb
->s_flags
& MS_RDONLY
) && features
) {
789 printk(KERN_ERR
"NILFS: couldn't mount RDWR because of "
790 "unsupported optional features (%llx)\n",
791 (unsigned long long)features
);
798 * nilfs_fill_super() - initialize a super block instance
800 * @data: mount options
801 * @silent: silent mode flag
802 * @nilfs: the_nilfs struct
804 * This function is called exclusively by nilfs->ns_mount_mutex.
805 * So, the recovery process is protected from other simultaneous mounts.
808 nilfs_fill_super(struct super_block
*sb
, void *data
, int silent
,
809 struct the_nilfs
*nilfs
)
811 struct nilfs_sb_info
*sbi
;
816 sbi
= kzalloc(sizeof(*sbi
), GFP_KERNEL
);
823 sbi
->s_nilfs
= nilfs
;
825 atomic_set(&sbi
->s_count
, 1);
827 err
= init_nilfs(nilfs
, sbi
, (char *)data
);
831 spin_lock_init(&sbi
->s_inode_lock
);
832 INIT_LIST_HEAD(&sbi
->s_dirty_files
);
833 INIT_LIST_HEAD(&sbi
->s_list
);
836 * Following initialization is overlapped because
837 * nilfs_sb_info structure has been cleared at the beginning.
838 * But we reserve them to keep our interest and make ready
839 * for the future change.
841 get_random_bytes(&sbi
->s_next_generation
,
842 sizeof(sbi
->s_next_generation
));
843 spin_lock_init(&sbi
->s_next_gen_lock
);
845 sb
->s_op
= &nilfs_sops
;
846 sb
->s_export_op
= &nilfs_export_ops
;
849 sb
->s_bdi
= nilfs
->ns_bdi
;
851 err
= load_nilfs(nilfs
, sbi
);
855 cno
= nilfs_last_cno(nilfs
);
857 if (sb
->s_flags
& MS_RDONLY
) {
858 if (nilfs_test_opt(sbi
, SNAPSHOT
)) {
859 down_read(&nilfs
->ns_segctor_sem
);
860 err
= nilfs_cpfile_is_snapshot(nilfs
->ns_cpfile
,
861 sbi
->s_snapshot_cno
);
862 up_read(&nilfs
->ns_segctor_sem
);
870 "NILFS: The specified checkpoint is "
872 "(checkpoint number=%llu).\n",
873 (unsigned long long)sbi
->s_snapshot_cno
);
877 cno
= sbi
->s_snapshot_cno
;
881 err
= nilfs_attach_checkpoint(sbi
, cno
);
883 printk(KERN_ERR
"NILFS: error loading a checkpoint"
884 " (checkpoint number=%llu).\n", (unsigned long long)cno
);
888 if (!(sb
->s_flags
& MS_RDONLY
)) {
889 err
= nilfs_attach_segment_constructor(sbi
);
891 goto failed_checkpoint
;
894 root
= nilfs_iget(sb
, NILFS_ROOT_INO
);
896 printk(KERN_ERR
"NILFS: get root inode failed\n");
900 if (!S_ISDIR(root
->i_mode
) || !root
->i_blocks
|| !root
->i_size
) {
902 printk(KERN_ERR
"NILFS: corrupt root inode.\n");
906 sb
->s_root
= d_alloc_root(root
);
909 printk(KERN_ERR
"NILFS: get root dentry failed\n");
914 if (!(sb
->s_flags
& MS_RDONLY
)) {
915 down_write(&nilfs
->ns_sem
);
916 nilfs_setup_super(sbi
);
917 up_write(&nilfs
->ns_sem
);
920 down_write(&nilfs
->ns_super_sem
);
921 if (!nilfs_test_opt(sbi
, SNAPSHOT
))
922 nilfs
->ns_current
= sbi
;
923 up_write(&nilfs
->ns_super_sem
);
928 nilfs_detach_segment_constructor(sbi
);
931 nilfs_detach_checkpoint(sbi
);
935 sb
->s_fs_info
= NULL
;
936 nilfs_put_sbinfo(sbi
);
940 static int nilfs_remount(struct super_block
*sb
, int *flags
, char *data
)
942 struct nilfs_sb_info
*sbi
= NILFS_SB(sb
);
943 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
944 unsigned long old_sb_flags
;
945 struct nilfs_mount_options old_opts
;
946 int was_snapshot
, err
;
950 down_write(&nilfs
->ns_super_sem
);
951 old_sb_flags
= sb
->s_flags
;
952 old_opts
.mount_opt
= sbi
->s_mount_opt
;
953 old_opts
.snapshot_cno
= sbi
->s_snapshot_cno
;
954 was_snapshot
= nilfs_test_opt(sbi
, SNAPSHOT
);
956 if (!parse_options(data
, sb
, 1)) {
960 sb
->s_flags
= (sb
->s_flags
& ~MS_POSIXACL
);
963 if (was_snapshot
&& !(*flags
& MS_RDONLY
)) {
964 printk(KERN_ERR
"NILFS (device %s): cannot remount snapshot "
965 "read/write.\n", sb
->s_id
);
969 if (!nilfs_valid_fs(nilfs
)) {
970 printk(KERN_WARNING
"NILFS (device %s): couldn't "
971 "remount because the filesystem is in an "
972 "incomplete recovery state.\n", sb
->s_id
);
976 if ((*flags
& MS_RDONLY
) == (sb
->s_flags
& MS_RDONLY
))
978 if (*flags
& MS_RDONLY
) {
979 /* Shutting down the segment constructor */
980 nilfs_detach_segment_constructor(sbi
);
981 sb
->s_flags
|= MS_RDONLY
;
984 * Remounting a valid RW partition RDONLY, so set
985 * the RDONLY flag and then mark the partition as valid again.
987 down_write(&nilfs
->ns_sem
);
988 nilfs_cleanup_super(sbi
);
989 up_write(&nilfs
->ns_sem
);
994 * Mounting a RDONLY partition read-write, so reread and
995 * store the current valid flag. (It may have been changed
996 * by fsck since we originally mounted the partition.)
998 down_read(&nilfs
->ns_sem
);
999 features
= le64_to_cpu(nilfs
->ns_sbp
[0]->s_feature_compat_ro
) &
1000 ~NILFS_FEATURE_COMPAT_RO_SUPP
;
1001 up_read(&nilfs
->ns_sem
);
1003 printk(KERN_WARNING
"NILFS (device %s): couldn't "
1004 "remount RDWR because of unsupported optional "
1005 "features (%llx)\n",
1006 sb
->s_id
, (unsigned long long)features
);
1011 sb
->s_flags
&= ~MS_RDONLY
;
1013 err
= nilfs_attach_segment_constructor(sbi
);
1017 down_write(&nilfs
->ns_sem
);
1018 nilfs_setup_super(sbi
);
1019 up_write(&nilfs
->ns_sem
);
1022 up_write(&nilfs
->ns_super_sem
);
1027 sb
->s_flags
= old_sb_flags
;
1028 sbi
->s_mount_opt
= old_opts
.mount_opt
;
1029 sbi
->s_snapshot_cno
= old_opts
.snapshot_cno
;
1030 up_write(&nilfs
->ns_super_sem
);
1035 struct nilfs_super_data
{
1036 struct block_device
*bdev
;
1037 struct nilfs_sb_info
*sbi
;
1043 * nilfs_identify - pre-read mount options needed to identify mount instance
1044 * @data: mount options
1045 * @sd: nilfs_super_data
1047 static int nilfs_identify(char *data
, struct nilfs_super_data
*sd
)
1049 char *p
, *options
= data
;
1050 substring_t args
[MAX_OPT_ARGS
];
1055 p
= strsep(&options
, ",");
1056 if (p
!= NULL
&& *p
) {
1057 token
= match_token(p
, tokens
, args
);
1058 if (token
== Opt_snapshot
) {
1059 if (!(sd
->flags
& MS_RDONLY
))
1062 ret
= match_int(&args
[0], &option
);
1073 "NILFS: invalid mount option: %s\n", p
);
1077 BUG_ON(options
== data
);
1078 *(options
- 1) = ',';
1083 static int nilfs_set_bdev_super(struct super_block
*s
, void *data
)
1085 struct nilfs_super_data
*sd
= data
;
1087 s
->s_bdev
= sd
->bdev
;
1088 s
->s_dev
= s
->s_bdev
->bd_dev
;
1092 static int nilfs_test_bdev_super(struct super_block
*s
, void *data
)
1094 struct nilfs_super_data
*sd
= data
;
1096 return sd
->sbi
&& s
->s_fs_info
== (void *)sd
->sbi
;
1100 nilfs_get_sb(struct file_system_type
*fs_type
, int flags
,
1101 const char *dev_name
, void *data
, struct vfsmount
*mnt
)
1103 struct nilfs_super_data sd
;
1104 struct super_block
*s
;
1105 fmode_t mode
= FMODE_READ
;
1106 struct the_nilfs
*nilfs
;
1107 int err
, need_to_close
= 1;
1109 if (!(flags
& MS_RDONLY
))
1110 mode
|= FMODE_WRITE
;
1112 sd
.bdev
= open_bdev_exclusive(dev_name
, mode
, fs_type
);
1113 if (IS_ERR(sd
.bdev
))
1114 return PTR_ERR(sd
.bdev
);
1117 * To get mount instance using sget() vfs-routine, NILFS needs
1118 * much more information than normal filesystems to identify mount
1119 * instance. For snapshot mounts, not only a mount type (ro-mount
1120 * or rw-mount) but also a checkpoint number is required.
1124 if (nilfs_identify((char *)data
, &sd
)) {
1129 nilfs
= find_or_create_nilfs(sd
.bdev
);
1135 mutex_lock(&nilfs
->ns_mount_mutex
);
1139 * Check if an exclusive mount exists or not.
1140 * Snapshot mounts coexist with a current mount
1141 * (i.e. rw-mount or ro-mount), whereas rw-mount and
1142 * ro-mount are mutually exclusive.
1144 down_read(&nilfs
->ns_super_sem
);
1145 if (nilfs
->ns_current
&&
1146 ((nilfs
->ns_current
->s_super
->s_flags
^ flags
)
1148 up_read(&nilfs
->ns_super_sem
);
1152 up_read(&nilfs
->ns_super_sem
);
1156 * Find existing nilfs_sb_info struct
1158 sd
.sbi
= nilfs_find_sbinfo(nilfs
, !(flags
& MS_RDONLY
), sd
.cno
);
1161 * Get super block instance holding the nilfs_sb_info struct.
1162 * A new instance is allocated if no existing mount is present or
1163 * existing instance has been unmounted.
1165 s
= sget(fs_type
, nilfs_test_bdev_super
, nilfs_set_bdev_super
, &sd
);
1167 nilfs_put_sbinfo(sd
.sbi
);
1175 char b
[BDEVNAME_SIZE
];
1177 /* New superblock instance created */
1180 strlcpy(s
->s_id
, bdevname(sd
.bdev
, b
), sizeof(s
->s_id
));
1181 sb_set_blocksize(s
, block_size(sd
.bdev
));
1183 err
= nilfs_fill_super(s
, data
, flags
& MS_SILENT
? 1 : 0,
1188 s
->s_flags
|= MS_ACTIVE
;
1192 mutex_unlock(&nilfs
->ns_mount_mutex
);
1195 close_bdev_exclusive(sd
.bdev
, mode
);
1196 simple_set_mnt(mnt
, s
);
1200 mutex_unlock(&nilfs
->ns_mount_mutex
);
1203 close_bdev_exclusive(sd
.bdev
, mode
);
1208 /* Abandoning the newly allocated superblock */
1209 mutex_unlock(&nilfs
->ns_mount_mutex
);
1211 deactivate_locked_super(s
);
1213 * deactivate_locked_super() invokes close_bdev_exclusive().
1214 * We must finish all post-cleaning before this call;
1215 * put_nilfs() needs the block device.
1220 struct file_system_type nilfs_fs_type
= {
1221 .owner
= THIS_MODULE
,
1223 .get_sb
= nilfs_get_sb
,
1224 .kill_sb
= kill_block_super
,
1225 .fs_flags
= FS_REQUIRES_DEV
,
1228 static void nilfs_inode_init_once(void *obj
)
1230 struct nilfs_inode_info
*ii
= obj
;
1232 INIT_LIST_HEAD(&ii
->i_dirty
);
1233 #ifdef CONFIG_NILFS_XATTR
1234 init_rwsem(&ii
->xattr_sem
);
1236 nilfs_btnode_cache_init_once(&ii
->i_btnode_cache
);
1237 ii
->i_bmap
= &ii
->i_bmap_data
;
1238 inode_init_once(&ii
->vfs_inode
);
1241 static void nilfs_segbuf_init_once(void *obj
)
1243 memset(obj
, 0, sizeof(struct nilfs_segment_buffer
));
1246 static void nilfs_destroy_cachep(void)
1248 if (nilfs_inode_cachep
)
1249 kmem_cache_destroy(nilfs_inode_cachep
);
1250 if (nilfs_transaction_cachep
)
1251 kmem_cache_destroy(nilfs_transaction_cachep
);
1252 if (nilfs_segbuf_cachep
)
1253 kmem_cache_destroy(nilfs_segbuf_cachep
);
1254 if (nilfs_btree_path_cache
)
1255 kmem_cache_destroy(nilfs_btree_path_cache
);
1258 static int __init
nilfs_init_cachep(void)
1260 nilfs_inode_cachep
= kmem_cache_create("nilfs2_inode_cache",
1261 sizeof(struct nilfs_inode_info
), 0,
1262 SLAB_RECLAIM_ACCOUNT
, nilfs_inode_init_once
);
1263 if (!nilfs_inode_cachep
)
1266 nilfs_transaction_cachep
= kmem_cache_create("nilfs2_transaction_cache",
1267 sizeof(struct nilfs_transaction_info
), 0,
1268 SLAB_RECLAIM_ACCOUNT
, NULL
);
1269 if (!nilfs_transaction_cachep
)
1272 nilfs_segbuf_cachep
= kmem_cache_create("nilfs2_segbuf_cache",
1273 sizeof(struct nilfs_segment_buffer
), 0,
1274 SLAB_RECLAIM_ACCOUNT
, nilfs_segbuf_init_once
);
1275 if (!nilfs_segbuf_cachep
)
1278 nilfs_btree_path_cache
= kmem_cache_create("nilfs2_btree_path_cache",
1279 sizeof(struct nilfs_btree_path
) * NILFS_BTREE_LEVEL_MAX
,
1281 if (!nilfs_btree_path_cache
)
1287 nilfs_destroy_cachep();
1291 static int __init
init_nilfs_fs(void)
1295 err
= nilfs_init_cachep();
1299 err
= register_filesystem(&nilfs_fs_type
);
1303 printk(KERN_INFO
"NILFS version 2 loaded\n");
1307 nilfs_destroy_cachep();
1312 static void __exit
exit_nilfs_fs(void)
1314 nilfs_destroy_cachep();
1315 unregister_filesystem(&nilfs_fs_type
);
1318 module_init(init_nilfs_fs
)
1319 module_exit(exit_nilfs_fs
)