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 * Written by Ryusuke Konishi.
19 * linux/fs/ext2/super.c
21 * Copyright (C) 1992, 1993, 1994, 1995
22 * Remy Card (card@masi.ibp.fr)
23 * Laboratoire MASI - Institut Blaise Pascal
24 * Universite Pierre et Marie Curie (Paris VI)
28 * linux/fs/minix/inode.c
30 * Copyright (C) 1991, 1992 Linus Torvalds
32 * Big-endian to little-endian byte-swapping/bitmaps by
33 * David S. Miller (davem@caip.rutgers.edu), 1995
36 #include <linux/module.h>
37 #include <linux/string.h>
38 #include <linux/slab.h>
39 #include <linux/init.h>
40 #include <linux/blkdev.h>
41 #include <linux/parser.h>
42 #include <linux/crc32.h>
43 #include <linux/vfs.h>
44 #include <linux/writeback.h>
45 #include <linux/seq_file.h>
46 #include <linux/mount.h>
55 #include "sufile.h" /* nilfs_sufile_resize(), nilfs_sufile_set_alloc_range() */
61 MODULE_AUTHOR("NTT Corp.");
62 MODULE_DESCRIPTION("A New Implementation of the Log-structured Filesystem "
64 MODULE_LICENSE("GPL");
66 static struct kmem_cache
*nilfs_inode_cachep
;
67 struct kmem_cache
*nilfs_transaction_cachep
;
68 struct kmem_cache
*nilfs_segbuf_cachep
;
69 struct kmem_cache
*nilfs_btree_path_cache
;
71 static int nilfs_setup_super(struct super_block
*sb
, int is_mount
);
72 static int nilfs_remount(struct super_block
*sb
, int *flags
, char *data
);
74 static void nilfs_set_error(struct super_block
*sb
)
76 struct the_nilfs
*nilfs
= sb
->s_fs_info
;
77 struct nilfs_super_block
**sbp
;
79 down_write(&nilfs
->ns_sem
);
80 if (!(nilfs
->ns_mount_state
& NILFS_ERROR_FS
)) {
81 nilfs
->ns_mount_state
|= NILFS_ERROR_FS
;
82 sbp
= nilfs_prepare_super(sb
, 0);
84 sbp
[0]->s_state
|= cpu_to_le16(NILFS_ERROR_FS
);
86 sbp
[1]->s_state
|= cpu_to_le16(NILFS_ERROR_FS
);
87 nilfs_commit_super(sb
, NILFS_SB_COMMIT_ALL
);
90 up_write(&nilfs
->ns_sem
);
94 * nilfs_error() - report failure condition on a filesystem
96 * nilfs_error() sets an ERROR_FS flag on the superblock as well as
97 * reporting an error message. It should be called when NILFS detects
98 * incoherences or defects of meta data on disk. As for sustainable
99 * errors such as a single-shot I/O error, nilfs_warning() or the printk()
100 * function should be used instead.
102 * The segment constructor must not call this function because it can
105 void nilfs_error(struct super_block
*sb
, const char *function
,
106 const char *fmt
, ...)
108 struct the_nilfs
*nilfs
= sb
->s_fs_info
;
109 struct va_format vaf
;
117 printk(KERN_CRIT
"NILFS error (device %s): %s: %pV\n",
118 sb
->s_id
, function
, &vaf
);
122 if (!(sb
->s_flags
& MS_RDONLY
)) {
125 if (nilfs_test_opt(nilfs
, ERRORS_RO
)) {
126 printk(KERN_CRIT
"Remounting filesystem read-only\n");
127 sb
->s_flags
|= MS_RDONLY
;
131 if (nilfs_test_opt(nilfs
, 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
, ...)
139 struct va_format vaf
;
147 printk(KERN_WARNING
"NILFS warning (device %s): %s: %pV\n",
148 sb
->s_id
, function
, &vaf
);
154 struct inode
*nilfs_alloc_inode(struct super_block
*sb
)
156 struct nilfs_inode_info
*ii
;
158 ii
= kmem_cache_alloc(nilfs_inode_cachep
, GFP_NOFS
);
164 ii
->vfs_inode
.i_version
= 1;
165 nilfs_mapping_init(&ii
->i_btnode_cache
, &ii
->vfs_inode
);
166 return &ii
->vfs_inode
;
169 static void nilfs_i_callback(struct rcu_head
*head
)
171 struct inode
*inode
= container_of(head
, struct inode
, i_rcu
);
172 struct nilfs_mdt_info
*mdi
= NILFS_MDT(inode
);
175 kfree(mdi
->mi_bgl
); /* kfree(NULL) is safe */
178 kmem_cache_free(nilfs_inode_cachep
, NILFS_I(inode
));
181 void nilfs_destroy_inode(struct inode
*inode
)
183 call_rcu(&inode
->i_rcu
, nilfs_i_callback
);
186 static int nilfs_sync_super(struct super_block
*sb
, int flag
)
188 struct the_nilfs
*nilfs
= sb
->s_fs_info
;
192 set_buffer_dirty(nilfs
->ns_sbh
[0]);
193 if (nilfs_test_opt(nilfs
, BARRIER
)) {
194 err
= __sync_dirty_buffer(nilfs
->ns_sbh
[0],
195 WRITE_SYNC
| WRITE_FLUSH_FUA
);
197 err
= sync_dirty_buffer(nilfs
->ns_sbh
[0]);
202 "NILFS: unable to write superblock (err=%d)\n", err
);
203 if (err
== -EIO
&& nilfs
->ns_sbh
[1]) {
205 * sbp[0] points to newer log than sbp[1],
206 * so copy sbp[0] to sbp[1] to take over sbp[0].
208 memcpy(nilfs
->ns_sbp
[1], nilfs
->ns_sbp
[0],
210 nilfs_fall_back_super_block(nilfs
);
214 struct nilfs_super_block
*sbp
= nilfs
->ns_sbp
[0];
216 nilfs
->ns_sbwcount
++;
219 * The latest segment becomes trailable from the position
220 * written in superblock.
222 clear_nilfs_discontinued(nilfs
);
224 /* update GC protection for recent segments */
225 if (nilfs
->ns_sbh
[1]) {
226 if (flag
== NILFS_SB_COMMIT_ALL
) {
227 set_buffer_dirty(nilfs
->ns_sbh
[1]);
228 if (sync_dirty_buffer(nilfs
->ns_sbh
[1]) < 0)
231 if (le64_to_cpu(nilfs
->ns_sbp
[1]->s_last_cno
) <
232 le64_to_cpu(nilfs
->ns_sbp
[0]->s_last_cno
))
233 sbp
= nilfs
->ns_sbp
[1];
236 spin_lock(&nilfs
->ns_last_segment_lock
);
237 nilfs
->ns_prot_seq
= le64_to_cpu(sbp
->s_last_seq
);
238 spin_unlock(&nilfs
->ns_last_segment_lock
);
244 void nilfs_set_log_cursor(struct nilfs_super_block
*sbp
,
245 struct the_nilfs
*nilfs
)
247 sector_t nfreeblocks
;
249 /* nilfs->ns_sem must be locked by the caller. */
250 nilfs_count_free_blocks(nilfs
, &nfreeblocks
);
251 sbp
->s_free_blocks_count
= cpu_to_le64(nfreeblocks
);
253 spin_lock(&nilfs
->ns_last_segment_lock
);
254 sbp
->s_last_seq
= cpu_to_le64(nilfs
->ns_last_seq
);
255 sbp
->s_last_pseg
= cpu_to_le64(nilfs
->ns_last_pseg
);
256 sbp
->s_last_cno
= cpu_to_le64(nilfs
->ns_last_cno
);
257 spin_unlock(&nilfs
->ns_last_segment_lock
);
260 struct nilfs_super_block
**nilfs_prepare_super(struct super_block
*sb
,
263 struct the_nilfs
*nilfs
= sb
->s_fs_info
;
264 struct nilfs_super_block
**sbp
= nilfs
->ns_sbp
;
266 /* nilfs->ns_sem must be locked by the caller. */
267 if (sbp
[0]->s_magic
!= cpu_to_le16(NILFS_SUPER_MAGIC
)) {
269 sbp
[1]->s_magic
== cpu_to_le16(NILFS_SUPER_MAGIC
)) {
270 memcpy(sbp
[0], sbp
[1], nilfs
->ns_sbsize
);
272 printk(KERN_CRIT
"NILFS: superblock broke on dev %s\n",
277 sbp
[1]->s_magic
!= cpu_to_le16(NILFS_SUPER_MAGIC
)) {
278 memcpy(sbp
[1], sbp
[0], nilfs
->ns_sbsize
);
282 nilfs_swap_super_block(nilfs
);
287 int nilfs_commit_super(struct super_block
*sb
, int flag
)
289 struct the_nilfs
*nilfs
= sb
->s_fs_info
;
290 struct nilfs_super_block
**sbp
= nilfs
->ns_sbp
;
293 /* nilfs->ns_sem must be locked by the caller. */
295 nilfs
->ns_sbwtime
= t
;
296 sbp
[0]->s_wtime
= cpu_to_le64(t
);
298 sbp
[0]->s_sum
= cpu_to_le32(crc32_le(nilfs
->ns_crc_seed
,
299 (unsigned char *)sbp
[0],
301 if (flag
== NILFS_SB_COMMIT_ALL
&& sbp
[1]) {
302 sbp
[1]->s_wtime
= sbp
[0]->s_wtime
;
304 sbp
[1]->s_sum
= cpu_to_le32(crc32_le(nilfs
->ns_crc_seed
,
305 (unsigned char *)sbp
[1],
308 clear_nilfs_sb_dirty(nilfs
);
309 nilfs
->ns_flushed_device
= 1;
310 /* make sure store to ns_flushed_device cannot be reordered */
312 return nilfs_sync_super(sb
, flag
);
316 * nilfs_cleanup_super() - write filesystem state for cleanup
317 * @sb: super block instance to be unmounted or degraded to read-only
319 * This function restores state flags in the on-disk super block.
320 * This will set "clean" flag (i.e. NILFS_VALID_FS) unless the
321 * filesystem was not clean previously.
323 int nilfs_cleanup_super(struct super_block
*sb
)
325 struct the_nilfs
*nilfs
= sb
->s_fs_info
;
326 struct nilfs_super_block
**sbp
;
327 int flag
= NILFS_SB_COMMIT
;
330 sbp
= nilfs_prepare_super(sb
, 0);
332 sbp
[0]->s_state
= cpu_to_le16(nilfs
->ns_mount_state
);
333 nilfs_set_log_cursor(sbp
[0], nilfs
);
334 if (sbp
[1] && sbp
[0]->s_last_cno
== sbp
[1]->s_last_cno
) {
336 * make the "clean" flag also to the opposite
337 * super block if both super blocks point to
338 * the same checkpoint.
340 sbp
[1]->s_state
= sbp
[0]->s_state
;
341 flag
= NILFS_SB_COMMIT_ALL
;
343 ret
= nilfs_commit_super(sb
, flag
);
349 * nilfs_move_2nd_super - relocate secondary super block
350 * @sb: super block instance
351 * @sb2off: new offset of the secondary super block (in bytes)
353 static int nilfs_move_2nd_super(struct super_block
*sb
, loff_t sb2off
)
355 struct the_nilfs
*nilfs
= sb
->s_fs_info
;
356 struct buffer_head
*nsbh
;
357 struct nilfs_super_block
*nsbp
;
358 sector_t blocknr
, newblocknr
;
359 unsigned long offset
;
360 int sb2i
; /* array index of the secondary superblock */
363 /* nilfs->ns_sem must be locked by the caller. */
364 if (nilfs
->ns_sbh
[1] &&
365 nilfs
->ns_sbh
[1]->b_blocknr
> nilfs
->ns_first_data_block
) {
367 blocknr
= nilfs
->ns_sbh
[1]->b_blocknr
;
368 } else if (nilfs
->ns_sbh
[0]->b_blocknr
> nilfs
->ns_first_data_block
) {
370 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
);
384 "NILFS warning: unable to move secondary superblock "
385 "to block %llu\n", (unsigned long long)newblocknr
);
389 nsbp
= (void *)nsbh
->b_data
+ offset
;
390 memset(nsbp
, 0, nilfs
->ns_blocksize
);
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
;
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
;
422 devsize
= i_size_read(sb
->s_bdev
->bd_inode
);
423 if (newsize
> devsize
)
427 * Write lock is required to protect some functions depending
428 * on the number of segments, the number of reserved segments,
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
);
442 ret
= nilfs_construct_segment(sb
);
446 down_write(&nilfs
->ns_sem
);
447 nilfs_move_2nd_super(sb
, sb2off
);
449 sbp
= nilfs_prepare_super(sb
, 0);
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
457 sbp
[0]->s_state
= cpu_to_le16(le16_to_cpu(sbp
[0]->s_state
) &
459 sbp
[0]->s_dev_size
= cpu_to_le64(newsize
);
460 sbp
[0]->s_nsegments
= cpu_to_le64(nilfs
->ns_nsegments
);
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
474 nilfs_sufile_set_alloc_range(nilfs
->ns_sufile
, 0, newnsegs
- 1);
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
);
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
;
505 /* This function is called when super block should be written back */
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
));
513 nilfs_set_log_cursor(sbp
[0], nilfs
);
514 nilfs_commit_super(sb
, NILFS_SB_COMMIT
);
517 up_write(&nilfs
->ns_sem
);
520 err
= nilfs_flush_device(nilfs
);
525 int nilfs_attach_checkpoint(struct super_block
*sb
, __u64 cno
, int curr_mnt
,
526 struct nilfs_root
**rootp
)
528 struct the_nilfs
*nilfs
= sb
->s_fs_info
;
529 struct nilfs_root
*root
;
530 struct nilfs_checkpoint
*raw_cp
;
531 struct buffer_head
*bh_cp
;
534 root
= nilfs_find_or_create_root(
535 nilfs
, curr_mnt
? NILFS_CPTREE_CURRENT_CNO
: cno
);
540 goto reuse
; /* already attached checkpoint */
542 down_read(&nilfs
->ns_segctor_sem
);
543 err
= nilfs_cpfile_get_checkpoint(nilfs
->ns_cpfile
, cno
, 0, &raw_cp
,
545 up_read(&nilfs
->ns_segctor_sem
);
547 if (err
== -ENOENT
|| err
== -EINVAL
) {
549 "NILFS: Invalid checkpoint "
550 "(checkpoint number=%llu)\n",
551 (unsigned long long)cno
);
557 err
= nilfs_ifile_read(sb
, root
, nilfs
->ns_inode_size
,
558 &raw_cp
->cp_ifile_inode
, &root
->ifile
);
562 atomic64_set(&root
->inodes_count
,
563 le64_to_cpu(raw_cp
->cp_inodes_count
));
564 atomic64_set(&root
->blocks_count
,
565 le64_to_cpu(raw_cp
->cp_blocks_count
));
567 nilfs_cpfile_put_checkpoint(nilfs
->ns_cpfile
, cno
, bh_cp
);
574 nilfs_cpfile_put_checkpoint(nilfs
->ns_cpfile
, cno
, bh_cp
);
576 nilfs_put_root(root
);
581 static int nilfs_freeze(struct super_block
*sb
)
583 struct the_nilfs
*nilfs
= sb
->s_fs_info
;
586 if (sb
->s_flags
& MS_RDONLY
)
589 /* Mark super block clean */
590 down_write(&nilfs
->ns_sem
);
591 err
= nilfs_cleanup_super(sb
);
592 up_write(&nilfs
->ns_sem
);
596 static int nilfs_unfreeze(struct super_block
*sb
)
598 struct the_nilfs
*nilfs
= sb
->s_fs_info
;
600 if (sb
->s_flags
& MS_RDONLY
)
603 down_write(&nilfs
->ns_sem
);
604 nilfs_setup_super(sb
, false);
605 up_write(&nilfs
->ns_sem
);
609 static int nilfs_statfs(struct dentry
*dentry
, struct kstatfs
*buf
)
611 struct super_block
*sb
= dentry
->d_sb
;
612 struct nilfs_root
*root
= NILFS_I(d_inode(dentry
))->i_root
;
613 struct the_nilfs
*nilfs
= root
->nilfs
;
614 u64 id
= huge_encode_dev(sb
->s_bdev
->bd_dev
);
615 unsigned long long blocks
;
616 unsigned long overhead
;
617 unsigned long nrsvblocks
;
618 sector_t nfreeblocks
;
619 u64 nmaxinodes
, nfreeinodes
;
623 * Compute all of the segment blocks
625 * The blocks before first segment and after last segment
628 blocks
= nilfs
->ns_blocks_per_segment
* nilfs
->ns_nsegments
629 - nilfs
->ns_first_data_block
;
630 nrsvblocks
= nilfs
->ns_nrsvsegs
* nilfs
->ns_blocks_per_segment
;
633 * Compute the overhead
635 * When distributing meta data blocks outside segment structure,
636 * We must count them as the overhead.
640 err
= nilfs_count_free_blocks(nilfs
, &nfreeblocks
);
644 err
= nilfs_ifile_count_free_inodes(root
->ifile
,
645 &nmaxinodes
, &nfreeinodes
);
648 "NILFS warning: fail to count free inodes: err %d.\n",
650 if (err
== -ERANGE
) {
652 * If nilfs_palloc_count_max_entries() returns
653 * -ERANGE error code then we simply treat
654 * curent inodes count as maximum possible and
655 * zero as free inodes value.
657 nmaxinodes
= atomic64_read(&root
->inodes_count
);
664 buf
->f_type
= NILFS_SUPER_MAGIC
;
665 buf
->f_bsize
= sb
->s_blocksize
;
666 buf
->f_blocks
= blocks
- overhead
;
667 buf
->f_bfree
= nfreeblocks
;
668 buf
->f_bavail
= (buf
->f_bfree
>= nrsvblocks
) ?
669 (buf
->f_bfree
- nrsvblocks
) : 0;
670 buf
->f_files
= nmaxinodes
;
671 buf
->f_ffree
= nfreeinodes
;
672 buf
->f_namelen
= NILFS_NAME_LEN
;
673 buf
->f_fsid
.val
[0] = (u32
)id
;
674 buf
->f_fsid
.val
[1] = (u32
)(id
>> 32);
679 static int nilfs_show_options(struct seq_file
*seq
, struct dentry
*dentry
)
681 struct super_block
*sb
= dentry
->d_sb
;
682 struct the_nilfs
*nilfs
= sb
->s_fs_info
;
683 struct nilfs_root
*root
= NILFS_I(d_inode(dentry
))->i_root
;
685 if (!nilfs_test_opt(nilfs
, BARRIER
))
686 seq_puts(seq
, ",nobarrier");
687 if (root
->cno
!= NILFS_CPTREE_CURRENT_CNO
)
688 seq_printf(seq
, ",cp=%llu", (unsigned long long)root
->cno
);
689 if (nilfs_test_opt(nilfs
, ERRORS_PANIC
))
690 seq_puts(seq
, ",errors=panic");
691 if (nilfs_test_opt(nilfs
, ERRORS_CONT
))
692 seq_puts(seq
, ",errors=continue");
693 if (nilfs_test_opt(nilfs
, STRICT_ORDER
))
694 seq_puts(seq
, ",order=strict");
695 if (nilfs_test_opt(nilfs
, NORECOVERY
))
696 seq_puts(seq
, ",norecovery");
697 if (nilfs_test_opt(nilfs
, DISCARD
))
698 seq_puts(seq
, ",discard");
703 static const struct super_operations nilfs_sops
= {
704 .alloc_inode
= nilfs_alloc_inode
,
705 .destroy_inode
= nilfs_destroy_inode
,
706 .dirty_inode
= nilfs_dirty_inode
,
707 .evict_inode
= nilfs_evict_inode
,
708 .put_super
= nilfs_put_super
,
709 .sync_fs
= nilfs_sync_fs
,
710 .freeze_fs
= nilfs_freeze
,
711 .unfreeze_fs
= nilfs_unfreeze
,
712 .statfs
= nilfs_statfs
,
713 .remount_fs
= nilfs_remount
,
714 .show_options
= nilfs_show_options
718 Opt_err_cont
, Opt_err_panic
, Opt_err_ro
,
719 Opt_barrier
, Opt_nobarrier
, Opt_snapshot
, Opt_order
, Opt_norecovery
,
720 Opt_discard
, Opt_nodiscard
, Opt_err
,
723 static match_table_t tokens
= {
724 {Opt_err_cont
, "errors=continue"},
725 {Opt_err_panic
, "errors=panic"},
726 {Opt_err_ro
, "errors=remount-ro"},
727 {Opt_barrier
, "barrier"},
728 {Opt_nobarrier
, "nobarrier"},
729 {Opt_snapshot
, "cp=%u"},
730 {Opt_order
, "order=%s"},
731 {Opt_norecovery
, "norecovery"},
732 {Opt_discard
, "discard"},
733 {Opt_nodiscard
, "nodiscard"},
737 static int parse_options(char *options
, struct super_block
*sb
, int is_remount
)
739 struct the_nilfs
*nilfs
= sb
->s_fs_info
;
741 substring_t args
[MAX_OPT_ARGS
];
746 while ((p
= strsep(&options
, ",")) != NULL
) {
751 token
= match_token(p
, tokens
, args
);
754 nilfs_set_opt(nilfs
, BARRIER
);
757 nilfs_clear_opt(nilfs
, BARRIER
);
760 if (strcmp(args
[0].from
, "relaxed") == 0)
761 /* Ordered data semantics */
762 nilfs_clear_opt(nilfs
, STRICT_ORDER
);
763 else if (strcmp(args
[0].from
, "strict") == 0)
764 /* Strict in-order semantics */
765 nilfs_set_opt(nilfs
, STRICT_ORDER
);
770 nilfs_write_opt(nilfs
, ERROR_MODE
, ERRORS_PANIC
);
773 nilfs_write_opt(nilfs
, ERROR_MODE
, ERRORS_RO
);
776 nilfs_write_opt(nilfs
, ERROR_MODE
, ERRORS_CONT
);
781 "NILFS: \"%s\" option is invalid "
782 "for remount.\n", p
);
787 nilfs_set_opt(nilfs
, NORECOVERY
);
790 nilfs_set_opt(nilfs
, DISCARD
);
793 nilfs_clear_opt(nilfs
, DISCARD
);
797 "NILFS: Unrecognized mount option \"%s\"\n", p
);
805 nilfs_set_default_options(struct super_block
*sb
,
806 struct nilfs_super_block
*sbp
)
808 struct the_nilfs
*nilfs
= sb
->s_fs_info
;
810 nilfs
->ns_mount_opt
=
811 NILFS_MOUNT_ERRORS_RO
| NILFS_MOUNT_BARRIER
;
814 static int nilfs_setup_super(struct super_block
*sb
, int is_mount
)
816 struct the_nilfs
*nilfs
= sb
->s_fs_info
;
817 struct nilfs_super_block
**sbp
;
821 /* nilfs->ns_sem must be locked by the caller. */
822 sbp
= nilfs_prepare_super(sb
, 0);
827 goto skip_mount_setup
;
829 max_mnt_count
= le16_to_cpu(sbp
[0]->s_max_mnt_count
);
830 mnt_count
= le16_to_cpu(sbp
[0]->s_mnt_count
);
832 if (nilfs
->ns_mount_state
& NILFS_ERROR_FS
) {
834 "NILFS warning: mounting fs with errors\n");
836 } else if (max_mnt_count
>= 0 && mnt_count
>= max_mnt_count
) {
838 "NILFS warning: maximal mount count reached\n");
842 sbp
[0]->s_max_mnt_count
= cpu_to_le16(NILFS_DFL_MAX_MNT_COUNT
);
844 sbp
[0]->s_mnt_count
= cpu_to_le16(mnt_count
+ 1);
845 sbp
[0]->s_mtime
= cpu_to_le64(get_seconds());
849 cpu_to_le16(le16_to_cpu(sbp
[0]->s_state
) & ~NILFS_VALID_FS
);
850 /* synchronize sbp[1] with sbp[0] */
852 memcpy(sbp
[1], sbp
[0], nilfs
->ns_sbsize
);
853 return nilfs_commit_super(sb
, NILFS_SB_COMMIT_ALL
);
856 struct nilfs_super_block
*nilfs_read_super_block(struct super_block
*sb
,
857 u64 pos
, int blocksize
,
858 struct buffer_head
**pbh
)
860 unsigned long long sb_index
= pos
;
861 unsigned long offset
;
863 offset
= do_div(sb_index
, blocksize
);
864 *pbh
= sb_bread(sb
, sb_index
);
867 return (struct nilfs_super_block
*)((char *)(*pbh
)->b_data
+ offset
);
870 int nilfs_store_magic_and_option(struct super_block
*sb
,
871 struct nilfs_super_block
*sbp
,
874 struct the_nilfs
*nilfs
= sb
->s_fs_info
;
876 sb
->s_magic
= le16_to_cpu(sbp
->s_magic
);
878 /* FS independent flags */
879 #ifdef NILFS_ATIME_DISABLE
880 sb
->s_flags
|= MS_NOATIME
;
883 nilfs_set_default_options(sb
, sbp
);
885 nilfs
->ns_resuid
= le16_to_cpu(sbp
->s_def_resuid
);
886 nilfs
->ns_resgid
= le16_to_cpu(sbp
->s_def_resgid
);
887 nilfs
->ns_interval
= le32_to_cpu(sbp
->s_c_interval
);
888 nilfs
->ns_watermark
= le32_to_cpu(sbp
->s_c_block_max
);
890 return !parse_options(data
, sb
, 0) ? -EINVAL
: 0 ;
893 int nilfs_check_feature_compatibility(struct super_block
*sb
,
894 struct nilfs_super_block
*sbp
)
898 features
= le64_to_cpu(sbp
->s_feature_incompat
) &
899 ~NILFS_FEATURE_INCOMPAT_SUPP
;
901 printk(KERN_ERR
"NILFS: couldn't mount because of unsupported "
902 "optional features (%llx)\n",
903 (unsigned long long)features
);
906 features
= le64_to_cpu(sbp
->s_feature_compat_ro
) &
907 ~NILFS_FEATURE_COMPAT_RO_SUPP
;
908 if (!(sb
->s_flags
& MS_RDONLY
) && features
) {
909 printk(KERN_ERR
"NILFS: couldn't mount RDWR because of "
910 "unsupported optional features (%llx)\n",
911 (unsigned long long)features
);
917 static int nilfs_get_root_dentry(struct super_block
*sb
,
918 struct nilfs_root
*root
,
919 struct dentry
**root_dentry
)
922 struct dentry
*dentry
;
925 inode
= nilfs_iget(sb
, root
, NILFS_ROOT_INO
);
927 printk(KERN_ERR
"NILFS: get root inode failed\n");
928 ret
= PTR_ERR(inode
);
931 if (!S_ISDIR(inode
->i_mode
) || !inode
->i_blocks
|| !inode
->i_size
) {
933 printk(KERN_ERR
"NILFS: corrupt root inode.\n");
938 if (root
->cno
== NILFS_CPTREE_CURRENT_CNO
) {
939 dentry
= d_find_alias(inode
);
941 dentry
= d_make_root(inode
);
950 dentry
= d_obtain_root(inode
);
951 if (IS_ERR(dentry
)) {
952 ret
= PTR_ERR(dentry
);
956 *root_dentry
= dentry
;
961 printk(KERN_ERR
"NILFS: get root dentry failed\n");
965 static int nilfs_attach_snapshot(struct super_block
*s
, __u64 cno
,
966 struct dentry
**root_dentry
)
968 struct the_nilfs
*nilfs
= s
->s_fs_info
;
969 struct nilfs_root
*root
;
972 mutex_lock(&nilfs
->ns_snapshot_mount_mutex
);
974 down_read(&nilfs
->ns_segctor_sem
);
975 ret
= nilfs_cpfile_is_snapshot(nilfs
->ns_cpfile
, cno
);
976 up_read(&nilfs
->ns_segctor_sem
);
978 ret
= (ret
== -ENOENT
) ? -EINVAL
: ret
;
981 printk(KERN_ERR
"NILFS: The specified checkpoint is "
982 "not a snapshot (checkpoint number=%llu).\n",
983 (unsigned long long)cno
);
988 ret
= nilfs_attach_checkpoint(s
, cno
, false, &root
);
990 printk(KERN_ERR
"NILFS: error loading snapshot "
991 "(checkpoint number=%llu).\n",
992 (unsigned long long)cno
);
995 ret
= nilfs_get_root_dentry(s
, root
, root_dentry
);
996 nilfs_put_root(root
);
998 mutex_unlock(&nilfs
->ns_snapshot_mount_mutex
);
1003 * nilfs_tree_is_busy() - try to shrink dentries of a checkpoint
1004 * @root_dentry: root dentry of the tree to be shrunk
1006 * This function returns true if the tree was in-use.
1008 static bool nilfs_tree_is_busy(struct dentry
*root_dentry
)
1010 shrink_dcache_parent(root_dentry
);
1011 return d_count(root_dentry
) > 1;
1014 int nilfs_checkpoint_is_mounted(struct super_block
*sb
, __u64 cno
)
1016 struct the_nilfs
*nilfs
= sb
->s_fs_info
;
1017 struct nilfs_root
*root
;
1018 struct inode
*inode
;
1019 struct dentry
*dentry
;
1022 if (cno
> nilfs
->ns_cno
)
1025 if (cno
>= nilfs_last_cno(nilfs
))
1026 return true; /* protect recent checkpoints */
1029 root
= nilfs_lookup_root(nilfs
, cno
);
1031 inode
= nilfs_ilookup(sb
, root
, NILFS_ROOT_INO
);
1033 dentry
= d_find_alias(inode
);
1035 ret
= nilfs_tree_is_busy(dentry
);
1040 nilfs_put_root(root
);
1046 * nilfs_fill_super() - initialize a super block instance
1048 * @data: mount options
1049 * @silent: silent mode flag
1051 * This function is called exclusively by nilfs->ns_mount_mutex.
1052 * So, the recovery process is protected from other simultaneous mounts.
1055 nilfs_fill_super(struct super_block
*sb
, void *data
, int silent
)
1057 struct the_nilfs
*nilfs
;
1058 struct nilfs_root
*fsroot
;
1062 nilfs
= alloc_nilfs(sb
->s_bdev
);
1066 sb
->s_fs_info
= nilfs
;
1068 err
= init_nilfs(nilfs
, sb
, (char *)data
);
1072 sb
->s_op
= &nilfs_sops
;
1073 sb
->s_export_op
= &nilfs_export_ops
;
1075 sb
->s_time_gran
= 1;
1076 sb
->s_max_links
= NILFS_LINK_MAX
;
1078 sb
->s_bdi
= &bdev_get_queue(sb
->s_bdev
)->backing_dev_info
;
1080 err
= load_nilfs(nilfs
, sb
);
1084 cno
= nilfs_last_cno(nilfs
);
1085 err
= nilfs_attach_checkpoint(sb
, cno
, true, &fsroot
);
1087 printk(KERN_ERR
"NILFS: error loading last checkpoint "
1088 "(checkpoint number=%llu).\n", (unsigned long long)cno
);
1092 if (!(sb
->s_flags
& MS_RDONLY
)) {
1093 err
= nilfs_attach_log_writer(sb
, fsroot
);
1095 goto failed_checkpoint
;
1098 err
= nilfs_get_root_dentry(sb
, fsroot
, &sb
->s_root
);
1100 goto failed_segctor
;
1102 nilfs_put_root(fsroot
);
1104 if (!(sb
->s_flags
& MS_RDONLY
)) {
1105 down_write(&nilfs
->ns_sem
);
1106 nilfs_setup_super(sb
, true);
1107 up_write(&nilfs
->ns_sem
);
1113 nilfs_detach_log_writer(sb
);
1116 nilfs_put_root(fsroot
);
1119 iput(nilfs
->ns_sufile
);
1120 iput(nilfs
->ns_cpfile
);
1121 iput(nilfs
->ns_dat
);
1124 destroy_nilfs(nilfs
);
1128 static int nilfs_remount(struct super_block
*sb
, int *flags
, char *data
)
1130 struct the_nilfs
*nilfs
= sb
->s_fs_info
;
1131 unsigned long old_sb_flags
;
1132 unsigned long old_mount_opt
;
1135 sync_filesystem(sb
);
1136 old_sb_flags
= sb
->s_flags
;
1137 old_mount_opt
= nilfs
->ns_mount_opt
;
1139 if (!parse_options(data
, sb
, 1)) {
1143 sb
->s_flags
= (sb
->s_flags
& ~MS_POSIXACL
);
1147 if (!nilfs_valid_fs(nilfs
)) {
1148 printk(KERN_WARNING
"NILFS (device %s): couldn't "
1149 "remount because the filesystem is in an "
1150 "incomplete recovery state.\n", sb
->s_id
);
1154 if ((*flags
& MS_RDONLY
) == (sb
->s_flags
& MS_RDONLY
))
1156 if (*flags
& MS_RDONLY
) {
1157 /* Shutting down log writer */
1158 nilfs_detach_log_writer(sb
);
1159 sb
->s_flags
|= MS_RDONLY
;
1162 * Remounting a valid RW partition RDONLY, so set
1163 * the RDONLY flag and then mark the partition as valid again.
1165 down_write(&nilfs
->ns_sem
);
1166 nilfs_cleanup_super(sb
);
1167 up_write(&nilfs
->ns_sem
);
1170 struct nilfs_root
*root
;
1173 * Mounting a RDONLY partition read-write, so reread and
1174 * store the current valid flag. (It may have been changed
1175 * by fsck since we originally mounted the partition.)
1177 down_read(&nilfs
->ns_sem
);
1178 features
= le64_to_cpu(nilfs
->ns_sbp
[0]->s_feature_compat_ro
) &
1179 ~NILFS_FEATURE_COMPAT_RO_SUPP
;
1180 up_read(&nilfs
->ns_sem
);
1182 printk(KERN_WARNING
"NILFS (device %s): couldn't "
1183 "remount RDWR because of unsupported optional "
1184 "features (%llx)\n",
1185 sb
->s_id
, (unsigned long long)features
);
1190 sb
->s_flags
&= ~MS_RDONLY
;
1192 root
= NILFS_I(d_inode(sb
->s_root
))->i_root
;
1193 err
= nilfs_attach_log_writer(sb
, root
);
1197 down_write(&nilfs
->ns_sem
);
1198 nilfs_setup_super(sb
, true);
1199 up_write(&nilfs
->ns_sem
);
1205 sb
->s_flags
= old_sb_flags
;
1206 nilfs
->ns_mount_opt
= old_mount_opt
;
1210 struct nilfs_super_data
{
1211 struct block_device
*bdev
;
1217 * nilfs_identify - pre-read mount options needed to identify mount instance
1218 * @data: mount options
1219 * @sd: nilfs_super_data
1221 static int nilfs_identify(char *data
, struct nilfs_super_data
*sd
)
1223 char *p
, *options
= data
;
1224 substring_t args
[MAX_OPT_ARGS
];
1229 p
= strsep(&options
, ",");
1230 if (p
!= NULL
&& *p
) {
1231 token
= match_token(p
, tokens
, args
);
1232 if (token
== Opt_snapshot
) {
1233 if (!(sd
->flags
& MS_RDONLY
)) {
1236 sd
->cno
= simple_strtoull(args
[0].from
,
1239 * No need to see the end pointer;
1240 * match_token() has done syntax
1249 "NILFS: invalid mount option: %s\n", p
);
1253 BUG_ON(options
== data
);
1254 *(options
- 1) = ',';
1259 static int nilfs_set_bdev_super(struct super_block
*s
, void *data
)
1262 s
->s_dev
= s
->s_bdev
->bd_dev
;
1266 static int nilfs_test_bdev_super(struct super_block
*s
, void *data
)
1268 return (void *)s
->s_bdev
== data
;
1271 static struct dentry
*
1272 nilfs_mount(struct file_system_type
*fs_type
, int flags
,
1273 const char *dev_name
, void *data
)
1275 struct nilfs_super_data sd
;
1276 struct super_block
*s
;
1277 fmode_t mode
= FMODE_READ
| FMODE_EXCL
;
1278 struct dentry
*root_dentry
;
1279 int err
, s_new
= false;
1281 if (!(flags
& MS_RDONLY
))
1282 mode
|= FMODE_WRITE
;
1284 sd
.bdev
= blkdev_get_by_path(dev_name
, mode
, fs_type
);
1285 if (IS_ERR(sd
.bdev
))
1286 return ERR_CAST(sd
.bdev
);
1290 if (nilfs_identify((char *)data
, &sd
)) {
1296 * once the super is inserted into the list by sget, s_umount
1297 * will protect the lockfs code from trying to start a snapshot
1298 * while we are mounting
1300 mutex_lock(&sd
.bdev
->bd_fsfreeze_mutex
);
1301 if (sd
.bdev
->bd_fsfreeze_count
> 0) {
1302 mutex_unlock(&sd
.bdev
->bd_fsfreeze_mutex
);
1306 s
= sget(fs_type
, nilfs_test_bdev_super
, nilfs_set_bdev_super
, flags
,
1308 mutex_unlock(&sd
.bdev
->bd_fsfreeze_mutex
);
1317 /* New superblock instance created */
1319 snprintf(s
->s_id
, sizeof(s
->s_id
), "%pg", sd
.bdev
);
1320 sb_set_blocksize(s
, block_size(sd
.bdev
));
1322 err
= nilfs_fill_super(s
, data
, flags
& MS_SILENT
? 1 : 0);
1326 s
->s_flags
|= MS_ACTIVE
;
1327 } else if (!sd
.cno
) {
1328 if (nilfs_tree_is_busy(s
->s_root
)) {
1329 if ((flags
^ s
->s_flags
) & MS_RDONLY
) {
1330 printk(KERN_ERR
"NILFS: the device already "
1331 "has a %s mount.\n",
1332 (s
->s_flags
& MS_RDONLY
) ?
1333 "read-only" : "read/write");
1339 * Try remount to setup mount states if the current
1340 * tree is not mounted and only snapshots use this sb.
1342 err
= nilfs_remount(s
, &flags
, data
);
1349 err
= nilfs_attach_snapshot(s
, sd
.cno
, &root_dentry
);
1353 root_dentry
= dget(s
->s_root
);
1357 blkdev_put(sd
.bdev
, mode
);
1362 deactivate_locked_super(s
);
1366 blkdev_put(sd
.bdev
, mode
);
1367 return ERR_PTR(err
);
1370 struct file_system_type nilfs_fs_type
= {
1371 .owner
= THIS_MODULE
,
1373 .mount
= nilfs_mount
,
1374 .kill_sb
= kill_block_super
,
1375 .fs_flags
= FS_REQUIRES_DEV
,
1377 MODULE_ALIAS_FS("nilfs2");
1379 static void nilfs_inode_init_once(void *obj
)
1381 struct nilfs_inode_info
*ii
= obj
;
1383 INIT_LIST_HEAD(&ii
->i_dirty
);
1384 #ifdef CONFIG_NILFS_XATTR
1385 init_rwsem(&ii
->xattr_sem
);
1387 address_space_init_once(&ii
->i_btnode_cache
);
1388 ii
->i_bmap
= &ii
->i_bmap_data
;
1389 inode_init_once(&ii
->vfs_inode
);
1392 static void nilfs_segbuf_init_once(void *obj
)
1394 memset(obj
, 0, sizeof(struct nilfs_segment_buffer
));
1397 static void nilfs_destroy_cachep(void)
1400 * Make sure all delayed rcu free inodes are flushed before we
1405 kmem_cache_destroy(nilfs_inode_cachep
);
1406 kmem_cache_destroy(nilfs_transaction_cachep
);
1407 kmem_cache_destroy(nilfs_segbuf_cachep
);
1408 kmem_cache_destroy(nilfs_btree_path_cache
);
1411 static int __init
nilfs_init_cachep(void)
1413 nilfs_inode_cachep
= kmem_cache_create("nilfs2_inode_cache",
1414 sizeof(struct nilfs_inode_info
), 0,
1415 SLAB_RECLAIM_ACCOUNT
|SLAB_ACCOUNT
,
1416 nilfs_inode_init_once
);
1417 if (!nilfs_inode_cachep
)
1420 nilfs_transaction_cachep
= kmem_cache_create("nilfs2_transaction_cache",
1421 sizeof(struct nilfs_transaction_info
), 0,
1422 SLAB_RECLAIM_ACCOUNT
, NULL
);
1423 if (!nilfs_transaction_cachep
)
1426 nilfs_segbuf_cachep
= kmem_cache_create("nilfs2_segbuf_cache",
1427 sizeof(struct nilfs_segment_buffer
), 0,
1428 SLAB_RECLAIM_ACCOUNT
, nilfs_segbuf_init_once
);
1429 if (!nilfs_segbuf_cachep
)
1432 nilfs_btree_path_cache
= kmem_cache_create("nilfs2_btree_path_cache",
1433 sizeof(struct nilfs_btree_path
) * NILFS_BTREE_LEVEL_MAX
,
1435 if (!nilfs_btree_path_cache
)
1441 nilfs_destroy_cachep();
1445 static int __init
init_nilfs_fs(void)
1449 err
= nilfs_init_cachep();
1453 err
= nilfs_sysfs_init();
1457 err
= register_filesystem(&nilfs_fs_type
);
1459 goto deinit_sysfs_entry
;
1461 printk(KERN_INFO
"NILFS version 2 loaded\n");
1467 nilfs_destroy_cachep();
1472 static void __exit
exit_nilfs_fs(void)
1474 nilfs_destroy_cachep();
1476 unregister_filesystem(&nilfs_fs_type
);
1479 module_init(init_nilfs_fs
)
1480 module_exit(exit_nilfs_fs
)