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/vfs.h>
49 #include <linux/writeback.h>
50 #include <linux/kobject.h>
51 #include <linux/seq_file.h>
52 #include <linux/mount.h>
66 MODULE_AUTHOR("NTT Corp.");
67 MODULE_DESCRIPTION("A New Implementation of the Log-structured Filesystem "
69 MODULE_LICENSE("GPL");
71 struct kmem_cache
*nilfs_inode_cachep
;
72 struct kmem_cache
*nilfs_transaction_cachep
;
73 struct kmem_cache
*nilfs_segbuf_cachep
;
74 struct kmem_cache
*nilfs_btree_path_cache
;
76 static int nilfs_remount(struct super_block
*sb
, int *flags
, char *data
);
78 static void nilfs_set_error(struct nilfs_sb_info
*sbi
)
80 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
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(sbi
, 0);
88 sbp
[0]->s_state
|= cpu_to_le16(NILFS_ERROR_FS
);
90 sbp
[1]->s_state
|= cpu_to_le16(NILFS_ERROR_FS
);
91 nilfs_commit_super(sbi
, NILFS_SB_COMMIT_ALL
);
94 up_write(&nilfs
->ns_sem
);
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
109 void nilfs_error(struct super_block
*sb
, const char *function
,
110 const char *fmt
, ...)
112 struct nilfs_sb_info
*sbi
= NILFS_SB(sb
);
116 printk(KERN_CRIT
"NILFS error (device %s): %s: ", sb
->s_id
, function
);
121 if (!(sb
->s_flags
& MS_RDONLY
)) {
122 nilfs_set_error(sbi
);
124 if (nilfs_test_opt(sbi
, ERRORS_RO
)) {
125 printk(KERN_CRIT
"Remounting filesystem read-only\n");
126 sb
->s_flags
|= MS_RDONLY
;
130 if (nilfs_test_opt(sbi
, ERRORS_PANIC
))
131 panic("NILFS (device %s): panic forced after error\n",
135 void nilfs_warning(struct super_block
*sb
, const char *function
,
136 const char *fmt
, ...)
141 printk(KERN_WARNING
"NILFS warning (device %s): %s: ",
149 struct inode
*nilfs_alloc_inode_common(struct the_nilfs
*nilfs
)
151 struct nilfs_inode_info
*ii
;
153 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 struct nilfs_mdt_info
*mdi
= NILFS_MDT(inode
);
174 kfree(mdi
->mi_bgl
); /* kfree(NULL) is safe */
177 kmem_cache_free(nilfs_inode_cachep
, NILFS_I(inode
));
180 static int nilfs_sync_super(struct nilfs_sb_info
*sbi
, int flag
)
182 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
186 set_buffer_dirty(nilfs
->ns_sbh
[0]);
188 if (nilfs_test_opt(sbi
, BARRIER
)) {
189 err
= __sync_dirty_buffer(nilfs
->ns_sbh
[0],
190 WRITE_SYNC
| WRITE_BARRIER
);
191 if (err
== -EOPNOTSUPP
) {
192 nilfs_warning(sbi
->s_super
, __func__
,
193 "barrier-based sync failed. "
194 "disabling barriers\n");
195 nilfs_clear_opt(sbi
, BARRIER
);
199 err
= sync_dirty_buffer(nilfs
->ns_sbh
[0]);
204 "NILFS: unable to write superblock (err=%d)\n", err
);
205 if (err
== -EIO
&& nilfs
->ns_sbh
[1]) {
207 * sbp[0] points to newer log than sbp[1],
208 * so copy sbp[0] to sbp[1] to take over sbp[0].
210 memcpy(nilfs
->ns_sbp
[1], nilfs
->ns_sbp
[0],
212 nilfs_fall_back_super_block(nilfs
);
216 struct nilfs_super_block
*sbp
= nilfs
->ns_sbp
[0];
218 nilfs
->ns_sbwcount
++;
221 * The latest segment becomes trailable from the position
222 * written in superblock.
224 clear_nilfs_discontinued(nilfs
);
226 /* update GC protection for recent segments */
227 if (nilfs
->ns_sbh
[1]) {
228 if (flag
== NILFS_SB_COMMIT_ALL
) {
229 set_buffer_dirty(nilfs
->ns_sbh
[1]);
230 if (sync_dirty_buffer(nilfs
->ns_sbh
[1]) < 0)
233 if (le64_to_cpu(nilfs
->ns_sbp
[1]->s_last_cno
) <
234 le64_to_cpu(nilfs
->ns_sbp
[0]->s_last_cno
))
235 sbp
= nilfs
->ns_sbp
[1];
238 spin_lock(&nilfs
->ns_last_segment_lock
);
239 nilfs
->ns_prot_seq
= le64_to_cpu(sbp
->s_last_seq
);
240 spin_unlock(&nilfs
->ns_last_segment_lock
);
246 void nilfs_set_log_cursor(struct nilfs_super_block
*sbp
,
247 struct the_nilfs
*nilfs
)
249 sector_t nfreeblocks
;
251 /* nilfs->ns_sem must be locked by the caller. */
252 nilfs_count_free_blocks(nilfs
, &nfreeblocks
);
253 sbp
->s_free_blocks_count
= cpu_to_le64(nfreeblocks
);
255 spin_lock(&nilfs
->ns_last_segment_lock
);
256 sbp
->s_last_seq
= cpu_to_le64(nilfs
->ns_last_seq
);
257 sbp
->s_last_pseg
= cpu_to_le64(nilfs
->ns_last_pseg
);
258 sbp
->s_last_cno
= cpu_to_le64(nilfs
->ns_last_cno
);
259 spin_unlock(&nilfs
->ns_last_segment_lock
);
262 struct nilfs_super_block
**nilfs_prepare_super(struct nilfs_sb_info
*sbi
,
265 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
266 struct nilfs_super_block
**sbp
= nilfs
->ns_sbp
;
268 /* nilfs->ns_sem must be locked by the caller. */
269 if (sbp
[0]->s_magic
!= cpu_to_le16(NILFS_SUPER_MAGIC
)) {
271 sbp
[1]->s_magic
== cpu_to_le16(NILFS_SUPER_MAGIC
)) {
272 memcpy(sbp
[0], sbp
[1], nilfs
->ns_sbsize
);
274 printk(KERN_CRIT
"NILFS: superblock broke on dev %s\n",
279 sbp
[1]->s_magic
!= cpu_to_le16(NILFS_SUPER_MAGIC
)) {
280 memcpy(sbp
[1], sbp
[0], nilfs
->ns_sbsize
);
284 nilfs_swap_super_block(nilfs
);
289 int nilfs_commit_super(struct nilfs_sb_info
*sbi
, int flag
)
291 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
292 struct nilfs_super_block
**sbp
= nilfs
->ns_sbp
;
295 /* nilfs->ns_sem must be locked by the caller. */
297 nilfs
->ns_sbwtime
= t
;
298 sbp
[0]->s_wtime
= cpu_to_le64(t
);
300 sbp
[0]->s_sum
= cpu_to_le32(crc32_le(nilfs
->ns_crc_seed
,
301 (unsigned char *)sbp
[0],
303 if (flag
== NILFS_SB_COMMIT_ALL
&& sbp
[1]) {
304 sbp
[1]->s_wtime
= sbp
[0]->s_wtime
;
306 sbp
[1]->s_sum
= cpu_to_le32(crc32_le(nilfs
->ns_crc_seed
,
307 (unsigned char *)sbp
[1],
310 clear_nilfs_sb_dirty(nilfs
);
311 return nilfs_sync_super(sbi
, flag
);
315 * nilfs_cleanup_super() - write filesystem state for cleanup
316 * @sbi: nilfs_sb_info to be unmounted or degraded to read-only
318 * This function restores state flags in the on-disk super block.
319 * This will set "clean" flag (i.e. NILFS_VALID_FS) unless the
320 * filesystem was not clean previously.
322 int nilfs_cleanup_super(struct nilfs_sb_info
*sbi
)
324 struct nilfs_super_block
**sbp
;
325 int flag
= NILFS_SB_COMMIT
;
328 sbp
= nilfs_prepare_super(sbi
, 0);
330 sbp
[0]->s_state
= cpu_to_le16(sbi
->s_nilfs
->ns_mount_state
);
331 nilfs_set_log_cursor(sbp
[0], sbi
->s_nilfs
);
332 if (sbp
[1] && sbp
[0]->s_last_cno
== sbp
[1]->s_last_cno
) {
334 * make the "clean" flag also to the opposite
335 * super block if both super blocks point to
336 * the same checkpoint.
338 sbp
[1]->s_state
= sbp
[0]->s_state
;
339 flag
= NILFS_SB_COMMIT_ALL
;
341 ret
= nilfs_commit_super(sbi
, flag
);
346 static void nilfs_put_super(struct super_block
*sb
)
348 struct nilfs_sb_info
*sbi
= NILFS_SB(sb
);
349 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
351 nilfs_detach_segment_constructor(sbi
);
353 if (!(sb
->s_flags
& MS_RDONLY
)) {
354 down_write(&nilfs
->ns_sem
);
355 nilfs_cleanup_super(sbi
);
356 up_write(&nilfs
->ns_sem
);
358 down_write(&nilfs
->ns_super_sem
);
359 if (nilfs
->ns_current
== sbi
)
360 nilfs
->ns_current
= NULL
;
361 list_del_init(&sbi
->s_list
);
362 up_write(&nilfs
->ns_super_sem
);
364 put_nilfs(sbi
->s_nilfs
);
366 sb
->s_fs_info
= NULL
;
367 nilfs_put_sbinfo(sbi
);
370 static int nilfs_sync_fs(struct super_block
*sb
, int wait
)
372 struct nilfs_sb_info
*sbi
= NILFS_SB(sb
);
373 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
374 struct nilfs_super_block
**sbp
;
377 /* This function is called when super block should be written back */
379 err
= nilfs_construct_segment(sb
);
381 down_write(&nilfs
->ns_sem
);
382 if (nilfs_sb_dirty(nilfs
)) {
383 sbp
= nilfs_prepare_super(sbi
, nilfs_sb_will_flip(nilfs
));
385 nilfs_set_log_cursor(sbp
[0], nilfs
);
386 nilfs_commit_super(sbi
, NILFS_SB_COMMIT
);
389 up_write(&nilfs
->ns_sem
);
394 int nilfs_attach_checkpoint(struct nilfs_sb_info
*sbi
, __u64 cno
, int curr_mnt
,
395 struct nilfs_root
**rootp
)
397 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
398 struct nilfs_root
*root
;
399 struct nilfs_checkpoint
*raw_cp
;
400 struct buffer_head
*bh_cp
;
403 root
= nilfs_find_or_create_root(
404 nilfs
, curr_mnt
? NILFS_CPTREE_CURRENT_CNO
: cno
);
409 goto reuse
; /* already attached checkpoint */
411 root
->ifile
= nilfs_ifile_new(sbi
, nilfs
->ns_inode_size
);
415 down_read(&nilfs
->ns_segctor_sem
);
416 err
= nilfs_cpfile_get_checkpoint(nilfs
->ns_cpfile
, cno
, 0, &raw_cp
,
418 up_read(&nilfs
->ns_segctor_sem
);
420 if (err
== -ENOENT
|| err
== -EINVAL
) {
422 "NILFS: Invalid checkpoint "
423 "(checkpoint number=%llu)\n",
424 (unsigned long long)cno
);
429 err
= nilfs_read_inode_common(root
->ifile
, &raw_cp
->cp_ifile_inode
);
432 atomic_set(&sbi
->s_inodes_count
, le64_to_cpu(raw_cp
->cp_inodes_count
));
433 atomic_set(&sbi
->s_blocks_count
, le64_to_cpu(raw_cp
->cp_blocks_count
));
435 nilfs_cpfile_put_checkpoint(nilfs
->ns_cpfile
, cno
, bh_cp
);
442 nilfs_cpfile_put_checkpoint(nilfs
->ns_cpfile
, cno
, bh_cp
);
444 nilfs_put_root(root
);
449 static int nilfs_statfs(struct dentry
*dentry
, struct kstatfs
*buf
)
451 struct super_block
*sb
= dentry
->d_sb
;
452 struct nilfs_sb_info
*sbi
= NILFS_SB(sb
);
453 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
454 u64 id
= huge_encode_dev(sb
->s_bdev
->bd_dev
);
455 unsigned long long blocks
;
456 unsigned long overhead
;
457 unsigned long nrsvblocks
;
458 sector_t nfreeblocks
;
462 * Compute all of the segment blocks
464 * The blocks before first segment and after last segment
467 blocks
= nilfs
->ns_blocks_per_segment
* nilfs
->ns_nsegments
468 - nilfs
->ns_first_data_block
;
469 nrsvblocks
= nilfs
->ns_nrsvsegs
* nilfs
->ns_blocks_per_segment
;
472 * Compute the overhead
474 * When distributing meta data blocks outside segment structure,
475 * We must count them as the overhead.
479 err
= nilfs_count_free_blocks(nilfs
, &nfreeblocks
);
483 buf
->f_type
= NILFS_SUPER_MAGIC
;
484 buf
->f_bsize
= sb
->s_blocksize
;
485 buf
->f_blocks
= blocks
- overhead
;
486 buf
->f_bfree
= nfreeblocks
;
487 buf
->f_bavail
= (buf
->f_bfree
>= nrsvblocks
) ?
488 (buf
->f_bfree
- nrsvblocks
) : 0;
489 buf
->f_files
= atomic_read(&sbi
->s_inodes_count
);
490 buf
->f_ffree
= 0; /* nilfs_count_free_inodes(sb); */
491 buf
->f_namelen
= NILFS_NAME_LEN
;
492 buf
->f_fsid
.val
[0] = (u32
)id
;
493 buf
->f_fsid
.val
[1] = (u32
)(id
>> 32);
498 static int nilfs_show_options(struct seq_file
*seq
, struct vfsmount
*vfs
)
500 struct super_block
*sb
= vfs
->mnt_sb
;
501 struct nilfs_sb_info
*sbi
= NILFS_SB(sb
);
503 if (!nilfs_test_opt(sbi
, BARRIER
))
504 seq_puts(seq
, ",nobarrier");
505 if (nilfs_test_opt(sbi
, SNAPSHOT
))
506 seq_printf(seq
, ",cp=%llu",
507 (unsigned long long int)sbi
->s_snapshot_cno
);
508 if (nilfs_test_opt(sbi
, ERRORS_PANIC
))
509 seq_puts(seq
, ",errors=panic");
510 if (nilfs_test_opt(sbi
, ERRORS_CONT
))
511 seq_puts(seq
, ",errors=continue");
512 if (nilfs_test_opt(sbi
, STRICT_ORDER
))
513 seq_puts(seq
, ",order=strict");
514 if (nilfs_test_opt(sbi
, NORECOVERY
))
515 seq_puts(seq
, ",norecovery");
516 if (nilfs_test_opt(sbi
, DISCARD
))
517 seq_puts(seq
, ",discard");
522 static const struct super_operations nilfs_sops
= {
523 .alloc_inode
= nilfs_alloc_inode
,
524 .destroy_inode
= nilfs_destroy_inode
,
525 .dirty_inode
= nilfs_dirty_inode
,
526 /* .write_inode = nilfs_write_inode, */
527 /* .put_inode = nilfs_put_inode, */
528 /* .drop_inode = nilfs_drop_inode, */
529 .evict_inode
= nilfs_evict_inode
,
530 .put_super
= nilfs_put_super
,
531 /* .write_super = nilfs_write_super, */
532 .sync_fs
= nilfs_sync_fs
,
533 /* .write_super_lockfs */
535 .statfs
= nilfs_statfs
,
536 .remount_fs
= nilfs_remount
,
538 .show_options
= nilfs_show_options
542 Opt_err_cont
, Opt_err_panic
, Opt_err_ro
,
543 Opt_barrier
, Opt_nobarrier
, Opt_snapshot
, Opt_order
, Opt_norecovery
,
544 Opt_discard
, Opt_nodiscard
, Opt_err
,
547 static match_table_t tokens
= {
548 {Opt_err_cont
, "errors=continue"},
549 {Opt_err_panic
, "errors=panic"},
550 {Opt_err_ro
, "errors=remount-ro"},
551 {Opt_barrier
, "barrier"},
552 {Opt_nobarrier
, "nobarrier"},
553 {Opt_snapshot
, "cp=%u"},
554 {Opt_order
, "order=%s"},
555 {Opt_norecovery
, "norecovery"},
556 {Opt_discard
, "discard"},
557 {Opt_nodiscard
, "nodiscard"},
561 static int parse_options(char *options
, struct super_block
*sb
, int is_remount
)
563 struct nilfs_sb_info
*sbi
= NILFS_SB(sb
);
565 substring_t args
[MAX_OPT_ARGS
];
571 while ((p
= strsep(&options
, ",")) != NULL
) {
576 token
= match_token(p
, tokens
, args
);
579 nilfs_set_opt(sbi
, BARRIER
);
582 nilfs_clear_opt(sbi
, BARRIER
);
585 if (strcmp(args
[0].from
, "relaxed") == 0)
586 /* Ordered data semantics */
587 nilfs_clear_opt(sbi
, STRICT_ORDER
);
588 else if (strcmp(args
[0].from
, "strict") == 0)
589 /* Strict in-order semantics */
590 nilfs_set_opt(sbi
, STRICT_ORDER
);
595 nilfs_write_opt(sbi
, ERROR_MODE
, ERRORS_PANIC
);
598 nilfs_write_opt(sbi
, ERROR_MODE
, ERRORS_RO
);
601 nilfs_write_opt(sbi
, ERROR_MODE
, ERRORS_CONT
);
604 if (match_int(&args
[0], &option
) || option
<= 0)
607 if (!nilfs_test_opt(sbi
, SNAPSHOT
)) {
609 "NILFS: cannot change regular "
610 "mount to snapshot.\n");
612 } else if (option
!= sbi
->s_snapshot_cno
) {
614 "NILFS: cannot remount to a "
615 "different snapshot.\n");
620 if (!(sb
->s_flags
& MS_RDONLY
)) {
621 printk(KERN_ERR
"NILFS: cannot mount snapshot "
622 "read/write. A read-only option is "
626 sbi
->s_snapshot_cno
= option
;
627 nilfs_set_opt(sbi
, SNAPSHOT
);
630 nilfs_set_opt(sbi
, NORECOVERY
);
633 nilfs_set_opt(sbi
, DISCARD
);
636 nilfs_clear_opt(sbi
, DISCARD
);
640 "NILFS: Unrecognized mount option \"%s\"\n", p
);
648 nilfs_set_default_options(struct nilfs_sb_info
*sbi
,
649 struct nilfs_super_block
*sbp
)
652 NILFS_MOUNT_ERRORS_RO
| NILFS_MOUNT_BARRIER
;
655 static int nilfs_setup_super(struct nilfs_sb_info
*sbi
)
657 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
658 struct nilfs_super_block
**sbp
;
662 /* nilfs->ns_sem must be locked by the caller. */
663 sbp
= nilfs_prepare_super(sbi
, 0);
667 max_mnt_count
= le16_to_cpu(sbp
[0]->s_max_mnt_count
);
668 mnt_count
= le16_to_cpu(sbp
[0]->s_mnt_count
);
670 if (nilfs
->ns_mount_state
& NILFS_ERROR_FS
) {
672 "NILFS warning: mounting fs with errors\n");
674 } else if (max_mnt_count
>= 0 && mnt_count
>= max_mnt_count
) {
676 "NILFS warning: maximal mount count reached\n");
680 sbp
[0]->s_max_mnt_count
= cpu_to_le16(NILFS_DFL_MAX_MNT_COUNT
);
682 sbp
[0]->s_mnt_count
= cpu_to_le16(mnt_count
+ 1);
684 cpu_to_le16(le16_to_cpu(sbp
[0]->s_state
) & ~NILFS_VALID_FS
);
685 sbp
[0]->s_mtime
= cpu_to_le64(get_seconds());
686 /* synchronize sbp[1] with sbp[0] */
687 memcpy(sbp
[1], sbp
[0], nilfs
->ns_sbsize
);
688 return nilfs_commit_super(sbi
, NILFS_SB_COMMIT_ALL
);
691 struct nilfs_super_block
*nilfs_read_super_block(struct super_block
*sb
,
692 u64 pos
, int blocksize
,
693 struct buffer_head
**pbh
)
695 unsigned long long sb_index
= pos
;
696 unsigned long offset
;
698 offset
= do_div(sb_index
, blocksize
);
699 *pbh
= sb_bread(sb
, sb_index
);
702 return (struct nilfs_super_block
*)((char *)(*pbh
)->b_data
+ offset
);
705 int nilfs_store_magic_and_option(struct super_block
*sb
,
706 struct nilfs_super_block
*sbp
,
709 struct nilfs_sb_info
*sbi
= NILFS_SB(sb
);
711 sb
->s_magic
= le16_to_cpu(sbp
->s_magic
);
713 /* FS independent flags */
714 #ifdef NILFS_ATIME_DISABLE
715 sb
->s_flags
|= MS_NOATIME
;
718 nilfs_set_default_options(sbi
, sbp
);
720 sbi
->s_resuid
= le16_to_cpu(sbp
->s_def_resuid
);
721 sbi
->s_resgid
= le16_to_cpu(sbp
->s_def_resgid
);
722 sbi
->s_interval
= le32_to_cpu(sbp
->s_c_interval
);
723 sbi
->s_watermark
= le32_to_cpu(sbp
->s_c_block_max
);
725 return !parse_options(data
, sb
, 0) ? -EINVAL
: 0 ;
728 int nilfs_check_feature_compatibility(struct super_block
*sb
,
729 struct nilfs_super_block
*sbp
)
733 features
= le64_to_cpu(sbp
->s_feature_incompat
) &
734 ~NILFS_FEATURE_INCOMPAT_SUPP
;
736 printk(KERN_ERR
"NILFS: couldn't mount because of unsupported "
737 "optional features (%llx)\n",
738 (unsigned long long)features
);
741 features
= le64_to_cpu(sbp
->s_feature_compat_ro
) &
742 ~NILFS_FEATURE_COMPAT_RO_SUPP
;
743 if (!(sb
->s_flags
& MS_RDONLY
) && features
) {
744 printk(KERN_ERR
"NILFS: couldn't mount RDWR because of "
745 "unsupported optional features (%llx)\n",
746 (unsigned long long)features
);
753 * nilfs_fill_super() - initialize a super block instance
755 * @data: mount options
756 * @silent: silent mode flag
757 * @nilfs: the_nilfs struct
759 * This function is called exclusively by nilfs->ns_mount_mutex.
760 * So, the recovery process is protected from other simultaneous mounts.
763 nilfs_fill_super(struct super_block
*sb
, void *data
, int silent
,
764 struct the_nilfs
*nilfs
)
766 struct nilfs_sb_info
*sbi
;
767 struct nilfs_root
*fsroot
;
772 sbi
= kzalloc(sizeof(*sbi
), GFP_KERNEL
);
779 sbi
->s_nilfs
= nilfs
;
781 atomic_set(&sbi
->s_count
, 1);
783 err
= init_nilfs(nilfs
, sbi
, (char *)data
);
787 spin_lock_init(&sbi
->s_inode_lock
);
788 INIT_LIST_HEAD(&sbi
->s_dirty_files
);
789 INIT_LIST_HEAD(&sbi
->s_list
);
792 * Following initialization is overlapped because
793 * nilfs_sb_info structure has been cleared at the beginning.
794 * But we reserve them to keep our interest and make ready
795 * for the future change.
797 get_random_bytes(&sbi
->s_next_generation
,
798 sizeof(sbi
->s_next_generation
));
799 spin_lock_init(&sbi
->s_next_gen_lock
);
801 sb
->s_op
= &nilfs_sops
;
802 sb
->s_export_op
= &nilfs_export_ops
;
805 sb
->s_bdi
= nilfs
->ns_bdi
;
807 err
= load_nilfs(nilfs
, sbi
);
811 cno
= nilfs_last_cno(nilfs
);
814 if (sb
->s_flags
& MS_RDONLY
) {
815 if (nilfs_test_opt(sbi
, SNAPSHOT
)) {
816 down_read(&nilfs
->ns_segctor_sem
);
817 err
= nilfs_cpfile_is_snapshot(nilfs
->ns_cpfile
,
818 sbi
->s_snapshot_cno
);
819 up_read(&nilfs
->ns_segctor_sem
);
827 "NILFS: The specified checkpoint is "
829 "(checkpoint number=%llu).\n",
830 (unsigned long long)sbi
->s_snapshot_cno
);
834 cno
= sbi
->s_snapshot_cno
;
839 err
= nilfs_attach_checkpoint(sbi
, cno
, curr_mnt
, &fsroot
);
841 printk(KERN_ERR
"NILFS: error loading a checkpoint"
842 " (checkpoint number=%llu).\n", (unsigned long long)cno
);
846 if (!(sb
->s_flags
& MS_RDONLY
)) {
847 err
= nilfs_attach_segment_constructor(sbi
, fsroot
);
849 goto failed_checkpoint
;
852 root
= nilfs_iget(sb
, fsroot
, NILFS_ROOT_INO
);
854 printk(KERN_ERR
"NILFS: get root inode failed\n");
858 if (!S_ISDIR(root
->i_mode
) || !root
->i_blocks
|| !root
->i_size
) {
860 printk(KERN_ERR
"NILFS: corrupt root inode.\n");
864 sb
->s_root
= d_alloc_root(root
);
867 printk(KERN_ERR
"NILFS: get root dentry failed\n");
872 nilfs_put_root(fsroot
);
874 if (!(sb
->s_flags
& MS_RDONLY
)) {
875 down_write(&nilfs
->ns_sem
);
876 nilfs_setup_super(sbi
);
877 up_write(&nilfs
->ns_sem
);
880 down_write(&nilfs
->ns_super_sem
);
881 list_add(&sbi
->s_list
, &nilfs
->ns_supers
);
882 if (!nilfs_test_opt(sbi
, SNAPSHOT
))
883 nilfs
->ns_current
= sbi
;
884 up_write(&nilfs
->ns_super_sem
);
889 nilfs_detach_segment_constructor(sbi
);
892 nilfs_put_root(fsroot
);
896 sb
->s_fs_info
= NULL
;
897 nilfs_put_sbinfo(sbi
);
901 static int nilfs_remount(struct super_block
*sb
, int *flags
, char *data
)
903 struct nilfs_sb_info
*sbi
= NILFS_SB(sb
);
904 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
905 unsigned long old_sb_flags
;
906 struct nilfs_mount_options old_opts
;
907 int was_snapshot
, err
;
909 down_write(&nilfs
->ns_super_sem
);
910 old_sb_flags
= sb
->s_flags
;
911 old_opts
.mount_opt
= sbi
->s_mount_opt
;
912 old_opts
.snapshot_cno
= sbi
->s_snapshot_cno
;
913 was_snapshot
= nilfs_test_opt(sbi
, SNAPSHOT
);
915 if (!parse_options(data
, sb
, 1)) {
919 sb
->s_flags
= (sb
->s_flags
& ~MS_POSIXACL
);
922 if (was_snapshot
&& !(*flags
& MS_RDONLY
)) {
923 printk(KERN_ERR
"NILFS (device %s): cannot remount snapshot "
924 "read/write.\n", sb
->s_id
);
928 if (!nilfs_valid_fs(nilfs
)) {
929 printk(KERN_WARNING
"NILFS (device %s): couldn't "
930 "remount because the filesystem is in an "
931 "incomplete recovery state.\n", sb
->s_id
);
935 if ((*flags
& MS_RDONLY
) == (sb
->s_flags
& MS_RDONLY
))
937 if (*flags
& MS_RDONLY
) {
938 /* Shutting down the segment constructor */
939 nilfs_detach_segment_constructor(sbi
);
940 sb
->s_flags
|= MS_RDONLY
;
943 * Remounting a valid RW partition RDONLY, so set
944 * the RDONLY flag and then mark the partition as valid again.
946 down_write(&nilfs
->ns_sem
);
947 nilfs_cleanup_super(sbi
);
948 up_write(&nilfs
->ns_sem
);
951 struct nilfs_root
*root
;
954 * Mounting a RDONLY partition read-write, so reread and
955 * store the current valid flag. (It may have been changed
956 * by fsck since we originally mounted the partition.)
958 down_read(&nilfs
->ns_sem
);
959 features
= le64_to_cpu(nilfs
->ns_sbp
[0]->s_feature_compat_ro
) &
960 ~NILFS_FEATURE_COMPAT_RO_SUPP
;
961 up_read(&nilfs
->ns_sem
);
963 printk(KERN_WARNING
"NILFS (device %s): couldn't "
964 "remount RDWR because of unsupported optional "
966 sb
->s_id
, (unsigned long long)features
);
971 sb
->s_flags
&= ~MS_RDONLY
;
973 root
= NILFS_I(sb
->s_root
->d_inode
)->i_root
;
974 err
= nilfs_attach_segment_constructor(sbi
, root
);
978 down_write(&nilfs
->ns_sem
);
979 nilfs_setup_super(sbi
);
980 up_write(&nilfs
->ns_sem
);
983 up_write(&nilfs
->ns_super_sem
);
987 sb
->s_flags
= old_sb_flags
;
988 sbi
->s_mount_opt
= old_opts
.mount_opt
;
989 sbi
->s_snapshot_cno
= old_opts
.snapshot_cno
;
990 up_write(&nilfs
->ns_super_sem
);
994 struct nilfs_super_data
{
995 struct block_device
*bdev
;
996 struct nilfs_sb_info
*sbi
;
1002 * nilfs_identify - pre-read mount options needed to identify mount instance
1003 * @data: mount options
1004 * @sd: nilfs_super_data
1006 static int nilfs_identify(char *data
, struct nilfs_super_data
*sd
)
1008 char *p
, *options
= data
;
1009 substring_t args
[MAX_OPT_ARGS
];
1014 p
= strsep(&options
, ",");
1015 if (p
!= NULL
&& *p
) {
1016 token
= match_token(p
, tokens
, args
);
1017 if (token
== Opt_snapshot
) {
1018 if (!(sd
->flags
& MS_RDONLY
))
1021 ret
= match_int(&args
[0], &option
);
1032 "NILFS: invalid mount option: %s\n", p
);
1036 BUG_ON(options
== data
);
1037 *(options
- 1) = ',';
1042 static int nilfs_set_bdev_super(struct super_block
*s
, void *data
)
1044 struct nilfs_super_data
*sd
= data
;
1046 s
->s_bdev
= sd
->bdev
;
1047 s
->s_dev
= s
->s_bdev
->bd_dev
;
1051 static int nilfs_test_bdev_super(struct super_block
*s
, void *data
)
1053 struct nilfs_super_data
*sd
= data
;
1055 return sd
->sbi
&& s
->s_fs_info
== (void *)sd
->sbi
;
1059 nilfs_get_sb(struct file_system_type
*fs_type
, int flags
,
1060 const char *dev_name
, void *data
, struct vfsmount
*mnt
)
1062 struct nilfs_super_data sd
;
1063 struct super_block
*s
;
1064 fmode_t mode
= FMODE_READ
;
1065 struct the_nilfs
*nilfs
;
1066 int err
, need_to_close
= 1;
1068 if (!(flags
& MS_RDONLY
))
1069 mode
|= FMODE_WRITE
;
1071 sd
.bdev
= open_bdev_exclusive(dev_name
, mode
, fs_type
);
1072 if (IS_ERR(sd
.bdev
))
1073 return PTR_ERR(sd
.bdev
);
1076 * To get mount instance using sget() vfs-routine, NILFS needs
1077 * much more information than normal filesystems to identify mount
1078 * instance. For snapshot mounts, not only a mount type (ro-mount
1079 * or rw-mount) but also a checkpoint number is required.
1083 if (nilfs_identify((char *)data
, &sd
)) {
1088 nilfs
= find_or_create_nilfs(sd
.bdev
);
1094 mutex_lock(&nilfs
->ns_mount_mutex
);
1098 * Check if an exclusive mount exists or not.
1099 * Snapshot mounts coexist with a current mount
1100 * (i.e. rw-mount or ro-mount), whereas rw-mount and
1101 * ro-mount are mutually exclusive.
1103 down_read(&nilfs
->ns_super_sem
);
1104 if (nilfs
->ns_current
&&
1105 ((nilfs
->ns_current
->s_super
->s_flags
^ flags
)
1107 up_read(&nilfs
->ns_super_sem
);
1111 up_read(&nilfs
->ns_super_sem
);
1115 * Find existing nilfs_sb_info struct
1117 sd
.sbi
= nilfs_find_sbinfo(nilfs
, !(flags
& MS_RDONLY
), sd
.cno
);
1120 * Get super block instance holding the nilfs_sb_info struct.
1121 * A new instance is allocated if no existing mount is present or
1122 * existing instance has been unmounted.
1124 s
= sget(fs_type
, nilfs_test_bdev_super
, nilfs_set_bdev_super
, &sd
);
1126 nilfs_put_sbinfo(sd
.sbi
);
1134 char b
[BDEVNAME_SIZE
];
1136 /* New superblock instance created */
1139 strlcpy(s
->s_id
, bdevname(sd
.bdev
, b
), sizeof(s
->s_id
));
1140 sb_set_blocksize(s
, block_size(sd
.bdev
));
1142 err
= nilfs_fill_super(s
, data
, flags
& MS_SILENT
? 1 : 0,
1147 s
->s_flags
|= MS_ACTIVE
;
1151 mutex_unlock(&nilfs
->ns_mount_mutex
);
1154 close_bdev_exclusive(sd
.bdev
, mode
);
1155 simple_set_mnt(mnt
, s
);
1159 mutex_unlock(&nilfs
->ns_mount_mutex
);
1162 close_bdev_exclusive(sd
.bdev
, mode
);
1166 /* Abandoning the newly allocated superblock */
1167 mutex_unlock(&nilfs
->ns_mount_mutex
);
1169 deactivate_locked_super(s
);
1171 * deactivate_locked_super() invokes close_bdev_exclusive().
1172 * We must finish all post-cleaning before this call;
1173 * put_nilfs() needs the block device.
1178 struct file_system_type nilfs_fs_type
= {
1179 .owner
= THIS_MODULE
,
1181 .get_sb
= nilfs_get_sb
,
1182 .kill_sb
= kill_block_super
,
1183 .fs_flags
= FS_REQUIRES_DEV
,
1186 static void nilfs_inode_init_once(void *obj
)
1188 struct nilfs_inode_info
*ii
= obj
;
1190 INIT_LIST_HEAD(&ii
->i_dirty
);
1191 #ifdef CONFIG_NILFS_XATTR
1192 init_rwsem(&ii
->xattr_sem
);
1194 nilfs_btnode_cache_init_once(&ii
->i_btnode_cache
);
1195 ii
->i_bmap
= &ii
->i_bmap_data
;
1196 inode_init_once(&ii
->vfs_inode
);
1199 static void nilfs_segbuf_init_once(void *obj
)
1201 memset(obj
, 0, sizeof(struct nilfs_segment_buffer
));
1204 static void nilfs_destroy_cachep(void)
1206 if (nilfs_inode_cachep
)
1207 kmem_cache_destroy(nilfs_inode_cachep
);
1208 if (nilfs_transaction_cachep
)
1209 kmem_cache_destroy(nilfs_transaction_cachep
);
1210 if (nilfs_segbuf_cachep
)
1211 kmem_cache_destroy(nilfs_segbuf_cachep
);
1212 if (nilfs_btree_path_cache
)
1213 kmem_cache_destroy(nilfs_btree_path_cache
);
1216 static int __init
nilfs_init_cachep(void)
1218 nilfs_inode_cachep
= kmem_cache_create("nilfs2_inode_cache",
1219 sizeof(struct nilfs_inode_info
), 0,
1220 SLAB_RECLAIM_ACCOUNT
, nilfs_inode_init_once
);
1221 if (!nilfs_inode_cachep
)
1224 nilfs_transaction_cachep
= kmem_cache_create("nilfs2_transaction_cache",
1225 sizeof(struct nilfs_transaction_info
), 0,
1226 SLAB_RECLAIM_ACCOUNT
, NULL
);
1227 if (!nilfs_transaction_cachep
)
1230 nilfs_segbuf_cachep
= kmem_cache_create("nilfs2_segbuf_cache",
1231 sizeof(struct nilfs_segment_buffer
), 0,
1232 SLAB_RECLAIM_ACCOUNT
, nilfs_segbuf_init_once
);
1233 if (!nilfs_segbuf_cachep
)
1236 nilfs_btree_path_cache
= kmem_cache_create("nilfs2_btree_path_cache",
1237 sizeof(struct nilfs_btree_path
) * NILFS_BTREE_LEVEL_MAX
,
1239 if (!nilfs_btree_path_cache
)
1245 nilfs_destroy_cachep();
1249 static int __init
init_nilfs_fs(void)
1253 err
= nilfs_init_cachep();
1257 err
= register_filesystem(&nilfs_fs_type
);
1261 printk(KERN_INFO
"NILFS version 2 loaded\n");
1265 nilfs_destroy_cachep();
1270 static void __exit
exit_nilfs_fs(void)
1272 nilfs_destroy_cachep();
1273 unregister_filesystem(&nilfs_fs_type
);
1276 module_init(init_nilfs_fs
)
1277 module_exit(exit_nilfs_fs
)