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/seq_file.h>
51 #include <linux/mount.h>
65 MODULE_AUTHOR("NTT Corp.");
66 MODULE_DESCRIPTION("A New Implementation of the Log-structured Filesystem "
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 nilfs_sb_info
*sbi
, int is_mount
);
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
);
113 struct va_format vaf
;
121 printk(KERN_CRIT
"NILFS error (device %s): %s: %pV\n",
122 sb
->s_id
, function
, &vaf
);
126 if (!(sb
->s_flags
& MS_RDONLY
)) {
127 nilfs_set_error(sbi
);
129 if (nilfs_test_opt(sbi
, ERRORS_RO
)) {
130 printk(KERN_CRIT
"Remounting filesystem read-only\n");
131 sb
->s_flags
|= MS_RDONLY
;
135 if (nilfs_test_opt(sbi
, ERRORS_PANIC
))
136 panic("NILFS (device %s): panic forced after error\n",
140 void nilfs_warning(struct super_block
*sb
, const char *function
,
141 const char *fmt
, ...)
143 struct va_format vaf
;
151 printk(KERN_WARNING
"NILFS warning (device %s): %s: %pV\n",
152 sb
->s_id
, function
, &vaf
);
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
);
168 ii
->vfs_inode
.i_version
= 1;
169 nilfs_btnode_cache_init(&ii
->i_btnode_cache
, 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
);
181 kfree(mdi
->mi_bgl
); /* kfree(NULL) is safe */
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 nilfs_sb_info
*sbi
, int flag
)
194 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
198 set_buffer_dirty(nilfs
->ns_sbh
[0]);
199 if (nilfs_test_opt(sbi
, BARRIER
)) {
200 err
= __sync_dirty_buffer(nilfs
->ns_sbh
[0],
201 WRITE_SYNC
| WRITE_FLUSH_FUA
);
203 err
= sync_dirty_buffer(nilfs
->ns_sbh
[0]);
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],
216 nilfs_fall_back_super_block(nilfs
);
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)
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
);
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 nilfs_sb_info
*sbi
,
269 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
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
)) {
275 sbp
[1]->s_magic
== cpu_to_le16(NILFS_SUPER_MAGIC
)) {
276 memcpy(sbp
[0], sbp
[1], nilfs
->ns_sbsize
);
278 printk(KERN_CRIT
"NILFS: superblock broke on dev %s\n",
283 sbp
[1]->s_magic
!= cpu_to_le16(NILFS_SUPER_MAGIC
)) {
284 memcpy(sbp
[1], sbp
[0], nilfs
->ns_sbsize
);
288 nilfs_swap_super_block(nilfs
);
293 int nilfs_commit_super(struct nilfs_sb_info
*sbi
, int flag
)
295 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
296 struct nilfs_super_block
**sbp
= nilfs
->ns_sbp
;
299 /* nilfs->ns_sem must be locked by the caller. */
301 nilfs
->ns_sbwtime
= t
;
302 sbp
[0]->s_wtime
= cpu_to_le64(t
);
304 sbp
[0]->s_sum
= cpu_to_le32(crc32_le(nilfs
->ns_crc_seed
,
305 (unsigned char *)sbp
[0],
307 if (flag
== NILFS_SB_COMMIT_ALL
&& sbp
[1]) {
308 sbp
[1]->s_wtime
= sbp
[0]->s_wtime
;
310 sbp
[1]->s_sum
= cpu_to_le32(crc32_le(nilfs
->ns_crc_seed
,
311 (unsigned char *)sbp
[1],
314 clear_nilfs_sb_dirty(nilfs
);
315 return nilfs_sync_super(sbi
, flag
);
319 * nilfs_cleanup_super() - write filesystem state for cleanup
320 * @sbi: nilfs_sb_info 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 nilfs_sb_info
*sbi
)
328 struct nilfs_super_block
**sbp
;
329 int flag
= NILFS_SB_COMMIT
;
332 sbp
= nilfs_prepare_super(sbi
, 0);
334 sbp
[0]->s_state
= cpu_to_le16(sbi
->s_nilfs
->ns_mount_state
);
335 nilfs_set_log_cursor(sbp
[0], sbi
->s_nilfs
);
336 if (sbp
[1] && sbp
[0]->s_last_cno
== sbp
[1]->s_last_cno
) {
338 * make the "clean" flag also to the opposite
339 * super block if both super blocks point to
340 * the same checkpoint.
342 sbp
[1]->s_state
= sbp
[0]->s_state
;
343 flag
= NILFS_SB_COMMIT_ALL
;
345 ret
= nilfs_commit_super(sbi
, flag
);
350 static void nilfs_put_super(struct super_block
*sb
)
352 struct nilfs_sb_info
*sbi
= NILFS_SB(sb
);
353 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
355 nilfs_detach_segment_constructor(sbi
);
357 if (!(sb
->s_flags
& MS_RDONLY
)) {
358 down_write(&nilfs
->ns_sem
);
359 nilfs_cleanup_super(sbi
);
360 up_write(&nilfs
->ns_sem
);
363 iput(nilfs
->ns_sufile
);
364 iput(nilfs
->ns_cpfile
);
367 destroy_nilfs(nilfs
);
369 sb
->s_fs_info
= NULL
;
373 static int nilfs_sync_fs(struct super_block
*sb
, int wait
)
375 struct nilfs_sb_info
*sbi
= NILFS_SB(sb
);
376 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
377 struct nilfs_super_block
**sbp
;
380 /* This function is called when super block should be written back */
382 err
= nilfs_construct_segment(sb
);
384 down_write(&nilfs
->ns_sem
);
385 if (nilfs_sb_dirty(nilfs
)) {
386 sbp
= nilfs_prepare_super(sbi
, nilfs_sb_will_flip(nilfs
));
388 nilfs_set_log_cursor(sbp
[0], nilfs
);
389 nilfs_commit_super(sbi
, NILFS_SB_COMMIT
);
392 up_write(&nilfs
->ns_sem
);
397 int nilfs_attach_checkpoint(struct nilfs_sb_info
*sbi
, __u64 cno
, int curr_mnt
,
398 struct nilfs_root
**rootp
)
400 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
401 struct nilfs_root
*root
;
402 struct nilfs_checkpoint
*raw_cp
;
403 struct buffer_head
*bh_cp
;
406 root
= nilfs_find_or_create_root(
407 nilfs
, curr_mnt
? NILFS_CPTREE_CURRENT_CNO
: cno
);
412 goto reuse
; /* already attached checkpoint */
414 down_read(&nilfs
->ns_segctor_sem
);
415 err
= nilfs_cpfile_get_checkpoint(nilfs
->ns_cpfile
, cno
, 0, &raw_cp
,
417 up_read(&nilfs
->ns_segctor_sem
);
419 if (err
== -ENOENT
|| err
== -EINVAL
) {
421 "NILFS: Invalid checkpoint "
422 "(checkpoint number=%llu)\n",
423 (unsigned long long)cno
);
429 err
= nilfs_ifile_read(sbi
->s_super
, root
, nilfs
->ns_inode_size
,
430 &raw_cp
->cp_ifile_inode
, &root
->ifile
);
434 atomic_set(&root
->inodes_count
, le64_to_cpu(raw_cp
->cp_inodes_count
));
435 atomic_set(&root
->blocks_count
, le64_to_cpu(raw_cp
->cp_blocks_count
));
437 nilfs_cpfile_put_checkpoint(nilfs
->ns_cpfile
, cno
, bh_cp
);
444 nilfs_cpfile_put_checkpoint(nilfs
->ns_cpfile
, cno
, bh_cp
);
446 nilfs_put_root(root
);
451 static int nilfs_freeze(struct super_block
*sb
)
453 struct nilfs_sb_info
*sbi
= NILFS_SB(sb
);
454 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
457 if (sb
->s_flags
& MS_RDONLY
)
460 /* Mark super block clean */
461 down_write(&nilfs
->ns_sem
);
462 err
= nilfs_cleanup_super(sbi
);
463 up_write(&nilfs
->ns_sem
);
467 static int nilfs_unfreeze(struct super_block
*sb
)
469 struct nilfs_sb_info
*sbi
= NILFS_SB(sb
);
470 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
472 if (sb
->s_flags
& MS_RDONLY
)
475 down_write(&nilfs
->ns_sem
);
476 nilfs_setup_super(sbi
, false);
477 up_write(&nilfs
->ns_sem
);
481 static int nilfs_statfs(struct dentry
*dentry
, struct kstatfs
*buf
)
483 struct super_block
*sb
= dentry
->d_sb
;
484 struct nilfs_root
*root
= NILFS_I(dentry
->d_inode
)->i_root
;
485 struct the_nilfs
*nilfs
= root
->nilfs
;
486 u64 id
= huge_encode_dev(sb
->s_bdev
->bd_dev
);
487 unsigned long long blocks
;
488 unsigned long overhead
;
489 unsigned long nrsvblocks
;
490 sector_t nfreeblocks
;
494 * Compute all of the segment blocks
496 * The blocks before first segment and after last segment
499 blocks
= nilfs
->ns_blocks_per_segment
* nilfs
->ns_nsegments
500 - nilfs
->ns_first_data_block
;
501 nrsvblocks
= nilfs
->ns_nrsvsegs
* nilfs
->ns_blocks_per_segment
;
504 * Compute the overhead
506 * When distributing meta data blocks outside segment structure,
507 * We must count them as the overhead.
511 err
= nilfs_count_free_blocks(nilfs
, &nfreeblocks
);
515 buf
->f_type
= NILFS_SUPER_MAGIC
;
516 buf
->f_bsize
= sb
->s_blocksize
;
517 buf
->f_blocks
= blocks
- overhead
;
518 buf
->f_bfree
= nfreeblocks
;
519 buf
->f_bavail
= (buf
->f_bfree
>= nrsvblocks
) ?
520 (buf
->f_bfree
- nrsvblocks
) : 0;
521 buf
->f_files
= atomic_read(&root
->inodes_count
);
522 buf
->f_ffree
= 0; /* nilfs_count_free_inodes(sb); */
523 buf
->f_namelen
= NILFS_NAME_LEN
;
524 buf
->f_fsid
.val
[0] = (u32
)id
;
525 buf
->f_fsid
.val
[1] = (u32
)(id
>> 32);
530 static int nilfs_show_options(struct seq_file
*seq
, struct vfsmount
*vfs
)
532 struct super_block
*sb
= vfs
->mnt_sb
;
533 struct nilfs_sb_info
*sbi
= NILFS_SB(sb
);
534 struct nilfs_root
*root
= NILFS_I(vfs
->mnt_root
->d_inode
)->i_root
;
536 if (!nilfs_test_opt(sbi
, BARRIER
))
537 seq_puts(seq
, ",nobarrier");
538 if (root
->cno
!= NILFS_CPTREE_CURRENT_CNO
)
539 seq_printf(seq
, ",cp=%llu", (unsigned long long)root
->cno
);
540 if (nilfs_test_opt(sbi
, ERRORS_PANIC
))
541 seq_puts(seq
, ",errors=panic");
542 if (nilfs_test_opt(sbi
, ERRORS_CONT
))
543 seq_puts(seq
, ",errors=continue");
544 if (nilfs_test_opt(sbi
, STRICT_ORDER
))
545 seq_puts(seq
, ",order=strict");
546 if (nilfs_test_opt(sbi
, NORECOVERY
))
547 seq_puts(seq
, ",norecovery");
548 if (nilfs_test_opt(sbi
, DISCARD
))
549 seq_puts(seq
, ",discard");
554 static const struct super_operations nilfs_sops
= {
555 .alloc_inode
= nilfs_alloc_inode
,
556 .destroy_inode
= nilfs_destroy_inode
,
557 .dirty_inode
= nilfs_dirty_inode
,
558 /* .write_inode = nilfs_write_inode, */
559 /* .put_inode = nilfs_put_inode, */
560 /* .drop_inode = nilfs_drop_inode, */
561 .evict_inode
= nilfs_evict_inode
,
562 .put_super
= nilfs_put_super
,
563 /* .write_super = nilfs_write_super, */
564 .sync_fs
= nilfs_sync_fs
,
565 .freeze_fs
= nilfs_freeze
,
566 .unfreeze_fs
= nilfs_unfreeze
,
567 /* .write_super_lockfs */
569 .statfs
= nilfs_statfs
,
570 .remount_fs
= nilfs_remount
,
572 .show_options
= nilfs_show_options
576 Opt_err_cont
, Opt_err_panic
, Opt_err_ro
,
577 Opt_barrier
, Opt_nobarrier
, Opt_snapshot
, Opt_order
, Opt_norecovery
,
578 Opt_discard
, Opt_nodiscard
, Opt_err
,
581 static match_table_t tokens
= {
582 {Opt_err_cont
, "errors=continue"},
583 {Opt_err_panic
, "errors=panic"},
584 {Opt_err_ro
, "errors=remount-ro"},
585 {Opt_barrier
, "barrier"},
586 {Opt_nobarrier
, "nobarrier"},
587 {Opt_snapshot
, "cp=%u"},
588 {Opt_order
, "order=%s"},
589 {Opt_norecovery
, "norecovery"},
590 {Opt_discard
, "discard"},
591 {Opt_nodiscard
, "nodiscard"},
595 static int parse_options(char *options
, struct super_block
*sb
, int is_remount
)
597 struct nilfs_sb_info
*sbi
= NILFS_SB(sb
);
599 substring_t args
[MAX_OPT_ARGS
];
604 while ((p
= strsep(&options
, ",")) != NULL
) {
609 token
= match_token(p
, tokens
, args
);
612 nilfs_set_opt(sbi
, BARRIER
);
615 nilfs_clear_opt(sbi
, BARRIER
);
618 if (strcmp(args
[0].from
, "relaxed") == 0)
619 /* Ordered data semantics */
620 nilfs_clear_opt(sbi
, STRICT_ORDER
);
621 else if (strcmp(args
[0].from
, "strict") == 0)
622 /* Strict in-order semantics */
623 nilfs_set_opt(sbi
, STRICT_ORDER
);
628 nilfs_write_opt(sbi
, ERROR_MODE
, ERRORS_PANIC
);
631 nilfs_write_opt(sbi
, ERROR_MODE
, ERRORS_RO
);
634 nilfs_write_opt(sbi
, ERROR_MODE
, ERRORS_CONT
);
639 "NILFS: \"%s\" option is invalid "
640 "for remount.\n", p
);
645 nilfs_set_opt(sbi
, NORECOVERY
);
648 nilfs_set_opt(sbi
, DISCARD
);
651 nilfs_clear_opt(sbi
, DISCARD
);
655 "NILFS: Unrecognized mount option \"%s\"\n", p
);
663 nilfs_set_default_options(struct nilfs_sb_info
*sbi
,
664 struct nilfs_super_block
*sbp
)
667 NILFS_MOUNT_ERRORS_RO
| NILFS_MOUNT_BARRIER
;
670 static int nilfs_setup_super(struct nilfs_sb_info
*sbi
, int is_mount
)
672 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
673 struct nilfs_super_block
**sbp
;
677 /* nilfs->ns_sem must be locked by the caller. */
678 sbp
= nilfs_prepare_super(sbi
, 0);
683 goto skip_mount_setup
;
685 max_mnt_count
= le16_to_cpu(sbp
[0]->s_max_mnt_count
);
686 mnt_count
= le16_to_cpu(sbp
[0]->s_mnt_count
);
688 if (nilfs
->ns_mount_state
& NILFS_ERROR_FS
) {
690 "NILFS warning: mounting fs with errors\n");
692 } else if (max_mnt_count
>= 0 && mnt_count
>= max_mnt_count
) {
694 "NILFS warning: maximal mount count reached\n");
698 sbp
[0]->s_max_mnt_count
= cpu_to_le16(NILFS_DFL_MAX_MNT_COUNT
);
700 sbp
[0]->s_mnt_count
= cpu_to_le16(mnt_count
+ 1);
701 sbp
[0]->s_mtime
= cpu_to_le64(get_seconds());
705 cpu_to_le16(le16_to_cpu(sbp
[0]->s_state
) & ~NILFS_VALID_FS
);
706 /* synchronize sbp[1] with sbp[0] */
708 memcpy(sbp
[1], sbp
[0], nilfs
->ns_sbsize
);
709 return nilfs_commit_super(sbi
, NILFS_SB_COMMIT_ALL
);
712 struct nilfs_super_block
*nilfs_read_super_block(struct super_block
*sb
,
713 u64 pos
, int blocksize
,
714 struct buffer_head
**pbh
)
716 unsigned long long sb_index
= pos
;
717 unsigned long offset
;
719 offset
= do_div(sb_index
, blocksize
);
720 *pbh
= sb_bread(sb
, sb_index
);
723 return (struct nilfs_super_block
*)((char *)(*pbh
)->b_data
+ offset
);
726 int nilfs_store_magic_and_option(struct super_block
*sb
,
727 struct nilfs_super_block
*sbp
,
730 struct nilfs_sb_info
*sbi
= NILFS_SB(sb
);
732 sb
->s_magic
= le16_to_cpu(sbp
->s_magic
);
734 /* FS independent flags */
735 #ifdef NILFS_ATIME_DISABLE
736 sb
->s_flags
|= MS_NOATIME
;
739 nilfs_set_default_options(sbi
, sbp
);
741 sbi
->s_resuid
= le16_to_cpu(sbp
->s_def_resuid
);
742 sbi
->s_resgid
= le16_to_cpu(sbp
->s_def_resgid
);
743 sbi
->s_interval
= le32_to_cpu(sbp
->s_c_interval
);
744 sbi
->s_watermark
= le32_to_cpu(sbp
->s_c_block_max
);
746 return !parse_options(data
, sb
, 0) ? -EINVAL
: 0 ;
749 int nilfs_check_feature_compatibility(struct super_block
*sb
,
750 struct nilfs_super_block
*sbp
)
754 features
= le64_to_cpu(sbp
->s_feature_incompat
) &
755 ~NILFS_FEATURE_INCOMPAT_SUPP
;
757 printk(KERN_ERR
"NILFS: couldn't mount because of unsupported "
758 "optional features (%llx)\n",
759 (unsigned long long)features
);
762 features
= le64_to_cpu(sbp
->s_feature_compat_ro
) &
763 ~NILFS_FEATURE_COMPAT_RO_SUPP
;
764 if (!(sb
->s_flags
& MS_RDONLY
) && features
) {
765 printk(KERN_ERR
"NILFS: couldn't mount RDWR because of "
766 "unsupported optional features (%llx)\n",
767 (unsigned long long)features
);
773 static int nilfs_get_root_dentry(struct super_block
*sb
,
774 struct nilfs_root
*root
,
775 struct dentry
**root_dentry
)
778 struct dentry
*dentry
;
781 inode
= nilfs_iget(sb
, root
, NILFS_ROOT_INO
);
783 printk(KERN_ERR
"NILFS: get root inode failed\n");
784 ret
= PTR_ERR(inode
);
787 if (!S_ISDIR(inode
->i_mode
) || !inode
->i_blocks
|| !inode
->i_size
) {
789 printk(KERN_ERR
"NILFS: corrupt root inode.\n");
794 if (root
->cno
== NILFS_CPTREE_CURRENT_CNO
) {
795 dentry
= d_find_alias(inode
);
797 dentry
= d_alloc_root(inode
);
807 dentry
= d_obtain_alias(inode
);
808 if (IS_ERR(dentry
)) {
809 ret
= PTR_ERR(dentry
);
813 *root_dentry
= dentry
;
818 printk(KERN_ERR
"NILFS: get root dentry failed\n");
822 static int nilfs_attach_snapshot(struct super_block
*s
, __u64 cno
,
823 struct dentry
**root_dentry
)
825 struct the_nilfs
*nilfs
= NILFS_SB(s
)->s_nilfs
;
826 struct nilfs_root
*root
;
829 down_read(&nilfs
->ns_segctor_sem
);
830 ret
= nilfs_cpfile_is_snapshot(nilfs
->ns_cpfile
, cno
);
831 up_read(&nilfs
->ns_segctor_sem
);
833 ret
= (ret
== -ENOENT
) ? -EINVAL
: ret
;
836 printk(KERN_ERR
"NILFS: The specified checkpoint is "
837 "not a snapshot (checkpoint number=%llu).\n",
838 (unsigned long long)cno
);
843 ret
= nilfs_attach_checkpoint(NILFS_SB(s
), cno
, false, &root
);
845 printk(KERN_ERR
"NILFS: error loading snapshot "
846 "(checkpoint number=%llu).\n",
847 (unsigned long long)cno
);
850 ret
= nilfs_get_root_dentry(s
, root
, root_dentry
);
851 nilfs_put_root(root
);
856 static int nilfs_tree_was_touched(struct dentry
*root_dentry
)
858 return root_dentry
->d_count
> 1;
862 * nilfs_try_to_shrink_tree() - try to shrink dentries of a checkpoint
863 * @root_dentry: root dentry of the tree to be shrunk
865 * This function returns true if the tree was in-use.
867 static int nilfs_try_to_shrink_tree(struct dentry
*root_dentry
)
869 if (have_submounts(root_dentry
))
871 shrink_dcache_parent(root_dentry
);
872 return nilfs_tree_was_touched(root_dentry
);
875 int nilfs_checkpoint_is_mounted(struct super_block
*sb
, __u64 cno
)
877 struct the_nilfs
*nilfs
= NILFS_SB(sb
)->s_nilfs
;
878 struct nilfs_root
*root
;
880 struct dentry
*dentry
;
883 if (cno
< 0 || cno
> nilfs
->ns_cno
)
886 if (cno
>= nilfs_last_cno(nilfs
))
887 return true; /* protect recent checkpoints */
890 root
= nilfs_lookup_root(NILFS_SB(sb
)->s_nilfs
, cno
);
892 inode
= nilfs_ilookup(sb
, root
, NILFS_ROOT_INO
);
894 dentry
= d_find_alias(inode
);
896 if (nilfs_tree_was_touched(dentry
))
897 ret
= nilfs_try_to_shrink_tree(dentry
);
902 nilfs_put_root(root
);
908 * nilfs_fill_super() - initialize a super block instance
910 * @data: mount options
911 * @silent: silent mode flag
913 * This function is called exclusively by nilfs->ns_mount_mutex.
914 * So, the recovery process is protected from other simultaneous mounts.
917 nilfs_fill_super(struct super_block
*sb
, void *data
, int silent
)
919 struct the_nilfs
*nilfs
;
920 struct nilfs_sb_info
*sbi
;
921 struct nilfs_root
*fsroot
;
922 struct backing_dev_info
*bdi
;
926 sbi
= kzalloc(sizeof(*sbi
), GFP_KERNEL
);
933 nilfs
= alloc_nilfs(sb
->s_bdev
);
938 sbi
->s_nilfs
= nilfs
;
940 err
= init_nilfs(nilfs
, sbi
, (char *)data
);
944 spin_lock_init(&sbi
->s_inode_lock
);
945 INIT_LIST_HEAD(&sbi
->s_dirty_files
);
948 * Following initialization is overlapped because
949 * nilfs_sb_info structure has been cleared at the beginning.
950 * But we reserve them to keep our interest and make ready
951 * for the future change.
953 get_random_bytes(&sbi
->s_next_generation
,
954 sizeof(sbi
->s_next_generation
));
955 spin_lock_init(&sbi
->s_next_gen_lock
);
957 sb
->s_op
= &nilfs_sops
;
958 sb
->s_export_op
= &nilfs_export_ops
;
962 bdi
= sb
->s_bdev
->bd_inode
->i_mapping
->backing_dev_info
;
963 sb
->s_bdi
= bdi
? : &default_backing_dev_info
;
965 err
= load_nilfs(nilfs
, sbi
);
969 cno
= nilfs_last_cno(nilfs
);
970 err
= nilfs_attach_checkpoint(sbi
, cno
, true, &fsroot
);
972 printk(KERN_ERR
"NILFS: error loading last checkpoint "
973 "(checkpoint number=%llu).\n", (unsigned long long)cno
);
977 if (!(sb
->s_flags
& MS_RDONLY
)) {
978 err
= nilfs_attach_segment_constructor(sbi
, fsroot
);
980 goto failed_checkpoint
;
983 err
= nilfs_get_root_dentry(sb
, fsroot
, &sb
->s_root
);
987 nilfs_put_root(fsroot
);
989 if (!(sb
->s_flags
& MS_RDONLY
)) {
990 down_write(&nilfs
->ns_sem
);
991 nilfs_setup_super(sbi
, true);
992 up_write(&nilfs
->ns_sem
);
998 nilfs_detach_segment_constructor(sbi
);
1001 nilfs_put_root(fsroot
);
1004 iput(nilfs
->ns_sufile
);
1005 iput(nilfs
->ns_cpfile
);
1006 iput(nilfs
->ns_dat
);
1009 destroy_nilfs(nilfs
);
1012 sb
->s_fs_info
= NULL
;
1017 static int nilfs_remount(struct super_block
*sb
, int *flags
, char *data
)
1019 struct nilfs_sb_info
*sbi
= NILFS_SB(sb
);
1020 struct the_nilfs
*nilfs
= sbi
->s_nilfs
;
1021 unsigned long old_sb_flags
;
1022 unsigned long old_mount_opt
;
1025 old_sb_flags
= sb
->s_flags
;
1026 old_mount_opt
= sbi
->s_mount_opt
;
1028 if (!parse_options(data
, sb
, 1)) {
1032 sb
->s_flags
= (sb
->s_flags
& ~MS_POSIXACL
);
1036 if (!nilfs_valid_fs(nilfs
)) {
1037 printk(KERN_WARNING
"NILFS (device %s): couldn't "
1038 "remount because the filesystem is in an "
1039 "incomplete recovery state.\n", sb
->s_id
);
1043 if ((*flags
& MS_RDONLY
) == (sb
->s_flags
& MS_RDONLY
))
1045 if (*flags
& MS_RDONLY
) {
1046 /* Shutting down the segment constructor */
1047 nilfs_detach_segment_constructor(sbi
);
1048 sb
->s_flags
|= MS_RDONLY
;
1051 * Remounting a valid RW partition RDONLY, so set
1052 * the RDONLY flag and then mark the partition as valid again.
1054 down_write(&nilfs
->ns_sem
);
1055 nilfs_cleanup_super(sbi
);
1056 up_write(&nilfs
->ns_sem
);
1059 struct nilfs_root
*root
;
1062 * Mounting a RDONLY partition read-write, so reread and
1063 * store the current valid flag. (It may have been changed
1064 * by fsck since we originally mounted the partition.)
1066 down_read(&nilfs
->ns_sem
);
1067 features
= le64_to_cpu(nilfs
->ns_sbp
[0]->s_feature_compat_ro
) &
1068 ~NILFS_FEATURE_COMPAT_RO_SUPP
;
1069 up_read(&nilfs
->ns_sem
);
1071 printk(KERN_WARNING
"NILFS (device %s): couldn't "
1072 "remount RDWR because of unsupported optional "
1073 "features (%llx)\n",
1074 sb
->s_id
, (unsigned long long)features
);
1079 sb
->s_flags
&= ~MS_RDONLY
;
1081 root
= NILFS_I(sb
->s_root
->d_inode
)->i_root
;
1082 err
= nilfs_attach_segment_constructor(sbi
, root
);
1086 down_write(&nilfs
->ns_sem
);
1087 nilfs_setup_super(sbi
, true);
1088 up_write(&nilfs
->ns_sem
);
1094 sb
->s_flags
= old_sb_flags
;
1095 sbi
->s_mount_opt
= old_mount_opt
;
1099 struct nilfs_super_data
{
1100 struct block_device
*bdev
;
1101 struct nilfs_sb_info
*sbi
;
1107 * nilfs_identify - pre-read mount options needed to identify mount instance
1108 * @data: mount options
1109 * @sd: nilfs_super_data
1111 static int nilfs_identify(char *data
, struct nilfs_super_data
*sd
)
1113 char *p
, *options
= data
;
1114 substring_t args
[MAX_OPT_ARGS
];
1119 p
= strsep(&options
, ",");
1120 if (p
!= NULL
&& *p
) {
1121 token
= match_token(p
, tokens
, args
);
1122 if (token
== Opt_snapshot
) {
1123 if (!(sd
->flags
& MS_RDONLY
)) {
1126 sd
->cno
= simple_strtoull(args
[0].from
,
1129 * No need to see the end pointer;
1130 * match_token() has done syntax
1139 "NILFS: invalid mount option: %s\n", p
);
1143 BUG_ON(options
== data
);
1144 *(options
- 1) = ',';
1149 static int nilfs_set_bdev_super(struct super_block
*s
, void *data
)
1152 s
->s_dev
= s
->s_bdev
->bd_dev
;
1156 static int nilfs_test_bdev_super(struct super_block
*s
, void *data
)
1158 return (void *)s
->s_bdev
== data
;
1161 static struct dentry
*
1162 nilfs_mount(struct file_system_type
*fs_type
, int flags
,
1163 const char *dev_name
, void *data
)
1165 struct nilfs_super_data sd
;
1166 struct super_block
*s
;
1167 fmode_t mode
= FMODE_READ
| FMODE_EXCL
;
1168 struct dentry
*root_dentry
;
1169 int err
, s_new
= false;
1171 if (!(flags
& MS_RDONLY
))
1172 mode
|= FMODE_WRITE
;
1174 sd
.bdev
= blkdev_get_by_path(dev_name
, mode
, fs_type
);
1175 if (IS_ERR(sd
.bdev
))
1176 return ERR_CAST(sd
.bdev
);
1180 if (nilfs_identify((char *)data
, &sd
)) {
1186 * once the super is inserted into the list by sget, s_umount
1187 * will protect the lockfs code from trying to start a snapshot
1188 * while we are mounting
1190 mutex_lock(&sd
.bdev
->bd_fsfreeze_mutex
);
1191 if (sd
.bdev
->bd_fsfreeze_count
> 0) {
1192 mutex_unlock(&sd
.bdev
->bd_fsfreeze_mutex
);
1196 s
= sget(fs_type
, nilfs_test_bdev_super
, nilfs_set_bdev_super
, sd
.bdev
);
1197 mutex_unlock(&sd
.bdev
->bd_fsfreeze_mutex
);
1204 char b
[BDEVNAME_SIZE
];
1208 /* New superblock instance created */
1211 strlcpy(s
->s_id
, bdevname(sd
.bdev
, b
), sizeof(s
->s_id
));
1212 sb_set_blocksize(s
, block_size(sd
.bdev
));
1214 err
= nilfs_fill_super(s
, data
, flags
& MS_SILENT
? 1 : 0);
1218 s
->s_flags
|= MS_ACTIVE
;
1219 } else if (!sd
.cno
) {
1222 if (nilfs_tree_was_touched(s
->s_root
)) {
1223 busy
= nilfs_try_to_shrink_tree(s
->s_root
);
1224 if (busy
&& (flags
^ s
->s_flags
) & MS_RDONLY
) {
1225 printk(KERN_ERR
"NILFS: the device already "
1226 "has a %s mount.\n",
1227 (s
->s_flags
& MS_RDONLY
) ?
1228 "read-only" : "read/write");
1235 * Try remount to setup mount states if the current
1236 * tree is not mounted and only snapshots use this sb.
1238 err
= nilfs_remount(s
, &flags
, data
);
1245 err
= nilfs_attach_snapshot(s
, sd
.cno
, &root_dentry
);
1249 root_dentry
= dget(s
->s_root
);
1253 blkdev_put(sd
.bdev
, mode
);
1258 deactivate_locked_super(s
);
1262 blkdev_put(sd
.bdev
, mode
);
1263 return ERR_PTR(err
);
1266 struct file_system_type nilfs_fs_type
= {
1267 .owner
= THIS_MODULE
,
1269 .mount
= nilfs_mount
,
1270 .kill_sb
= kill_block_super
,
1271 .fs_flags
= FS_REQUIRES_DEV
,
1274 static void nilfs_inode_init_once(void *obj
)
1276 struct nilfs_inode_info
*ii
= obj
;
1278 INIT_LIST_HEAD(&ii
->i_dirty
);
1279 #ifdef CONFIG_NILFS_XATTR
1280 init_rwsem(&ii
->xattr_sem
);
1282 address_space_init_once(&ii
->i_btnode_cache
);
1283 ii
->i_bmap
= &ii
->i_bmap_data
;
1284 inode_init_once(&ii
->vfs_inode
);
1287 static void nilfs_segbuf_init_once(void *obj
)
1289 memset(obj
, 0, sizeof(struct nilfs_segment_buffer
));
1292 static void nilfs_destroy_cachep(void)
1294 if (nilfs_inode_cachep
)
1295 kmem_cache_destroy(nilfs_inode_cachep
);
1296 if (nilfs_transaction_cachep
)
1297 kmem_cache_destroy(nilfs_transaction_cachep
);
1298 if (nilfs_segbuf_cachep
)
1299 kmem_cache_destroy(nilfs_segbuf_cachep
);
1300 if (nilfs_btree_path_cache
)
1301 kmem_cache_destroy(nilfs_btree_path_cache
);
1304 static int __init
nilfs_init_cachep(void)
1306 nilfs_inode_cachep
= kmem_cache_create("nilfs2_inode_cache",
1307 sizeof(struct nilfs_inode_info
), 0,
1308 SLAB_RECLAIM_ACCOUNT
, nilfs_inode_init_once
);
1309 if (!nilfs_inode_cachep
)
1312 nilfs_transaction_cachep
= kmem_cache_create("nilfs2_transaction_cache",
1313 sizeof(struct nilfs_transaction_info
), 0,
1314 SLAB_RECLAIM_ACCOUNT
, NULL
);
1315 if (!nilfs_transaction_cachep
)
1318 nilfs_segbuf_cachep
= kmem_cache_create("nilfs2_segbuf_cache",
1319 sizeof(struct nilfs_segment_buffer
), 0,
1320 SLAB_RECLAIM_ACCOUNT
, nilfs_segbuf_init_once
);
1321 if (!nilfs_segbuf_cachep
)
1324 nilfs_btree_path_cache
= kmem_cache_create("nilfs2_btree_path_cache",
1325 sizeof(struct nilfs_btree_path
) * NILFS_BTREE_LEVEL_MAX
,
1327 if (!nilfs_btree_path_cache
)
1333 nilfs_destroy_cachep();
1337 static int __init
init_nilfs_fs(void)
1341 err
= nilfs_init_cachep();
1345 err
= register_filesystem(&nilfs_fs_type
);
1349 printk(KERN_INFO
"NILFS version 2 loaded\n");
1353 nilfs_destroy_cachep();
1358 static void __exit
exit_nilfs_fs(void)
1360 nilfs_destroy_cachep();
1361 unregister_filesystem(&nilfs_fs_type
);
1364 module_init(init_nilfs_fs
)
1365 module_exit(exit_nilfs_fs
)