2 * super.c - NILFS module and super block management.
4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
20 * Written by Ryusuke Konishi <ryusuke@osrg.net>
23 * linux/fs/ext2/super.c
25 * Copyright (C) 1992, 1993, 1994, 1995
26 * Remy Card (card@masi.ibp.fr)
27 * Laboratoire MASI - Institut Blaise Pascal
28 * Universite Pierre et Marie Curie (Paris VI)
32 * linux/fs/minix/inode.c
34 * Copyright (C) 1991, 1992 Linus Torvalds
36 * Big-endian to little-endian byte-swapping/bitmaps by
37 * David S. Miller (davem@caip.rutgers.edu), 1995
40 #include <linux/module.h>
41 #include <linux/string.h>
42 #include <linux/slab.h>
43 #include <linux/init.h>
44 #include <linux/blkdev.h>
45 #include <linux/parser.h>
46 #include <linux/random.h>
47 #include <linux/crc32.h>
48 #include <linux/smp_lock.h>
49 #include <linux/vfs.h>
50 #include <linux/writeback.h>
51 #include <linux/kobject.h>
52 #include <linux/exportfs.h>
53 #include <linux/seq_file.h>
54 #include <linux/mount.h>
67 MODULE_AUTHOR("NTT Corp.");
68 MODULE_DESCRIPTION("A New Implementation of the Log-structured Filesystem "
70 MODULE_LICENSE("GPL");
72 struct kmem_cache *nilfs_inode_cachep;
73 struct kmem_cache *nilfs_transaction_cachep;
74 struct kmem_cache *nilfs_segbuf_cachep;
75 struct kmem_cache *nilfs_btree_path_cache;
77 static int nilfs_remount(struct super_block *sb, int *flags, char *data);
79 static void nilfs_set_error(struct nilfs_sb_info *sbi)
81 struct the_nilfs *nilfs = sbi->s_nilfs;
82 struct nilfs_super_block **sbp;
84 down_write(&nilfs->ns_sem);
85 if (!(nilfs->ns_mount_state & NILFS_ERROR_FS)) {
86 nilfs->ns_mount_state |= NILFS_ERROR_FS;
87 sbp = nilfs_prepare_super(sbi, 0);
89 sbp[0]->s_state |= cpu_to_le16(NILFS_ERROR_FS);
91 sbp[1]->s_state |= cpu_to_le16(NILFS_ERROR_FS);
92 nilfs_commit_super(sbi, NILFS_SB_COMMIT_ALL);
95 up_write(&nilfs->ns_sem);
99 * nilfs_error() - report failure condition on a filesystem
101 * nilfs_error() sets an ERROR_FS flag on the superblock as well as
102 * reporting an error message. It should be called when NILFS detects
103 * incoherences or defects of meta data on disk. As for sustainable
104 * errors such as a single-shot I/O error, nilfs_warning() or the printk()
105 * function should be used instead.
107 * The segment constructor must not call this function because it can
110 void nilfs_error(struct super_block *sb, const char *function,
111 const char *fmt, ...)
113 struct nilfs_sb_info *sbi = NILFS_SB(sb);
117 printk(KERN_CRIT "NILFS error (device %s): %s: ", sb->s_id, function);
122 if (!(sb->s_flags & MS_RDONLY)) {
123 nilfs_set_error(sbi);
125 if (nilfs_test_opt(sbi, ERRORS_RO)) {
126 printk(KERN_CRIT "Remounting filesystem read-only\n");
127 sb->s_flags |= MS_RDONLY;
131 if (nilfs_test_opt(sbi, ERRORS_PANIC))
132 panic("NILFS (device %s): panic forced after error\n",
136 void nilfs_warning(struct super_block *sb, const char *function,
137 const char *fmt, ...)
142 printk(KERN_WARNING "NILFS warning (device %s): %s: ",
150 struct inode *nilfs_alloc_inode_common(struct the_nilfs *nilfs)
152 struct nilfs_inode_info *ii;
154 ii = kmem_cache_alloc(nilfs_inode_cachep, GFP_NOFS);
159 ii->vfs_inode.i_version = 1;
160 nilfs_btnode_cache_init(&ii->i_btnode_cache, nilfs->ns_bdi);
161 return &ii->vfs_inode;
164 struct inode *nilfs_alloc_inode(struct super_block *sb)
166 return nilfs_alloc_inode_common(NILFS_SB(sb)->s_nilfs);
169 void nilfs_destroy_inode(struct inode *inode)
171 kmem_cache_free(nilfs_inode_cachep, NILFS_I(inode));
174 static int nilfs_sync_super(struct nilfs_sb_info *sbi, int flag)
176 struct the_nilfs *nilfs = sbi->s_nilfs;
180 set_buffer_dirty(nilfs->ns_sbh[0]);
181 if (nilfs_test_opt(sbi, BARRIER)) {
182 err = __sync_dirty_buffer(nilfs->ns_sbh[0],
183 WRITE_SYNC | WRITE_FLUSH_FUA);
185 err = sync_dirty_buffer(nilfs->ns_sbh[0]);
190 "NILFS: unable to write superblock (err=%d)\n", err);
191 if (err == -EIO && nilfs->ns_sbh[1]) {
193 * sbp[0] points to newer log than sbp[1],
194 * so copy sbp[0] to sbp[1] to take over sbp[0].
196 memcpy(nilfs->ns_sbp[1], nilfs->ns_sbp[0],
198 nilfs_fall_back_super_block(nilfs);
202 struct nilfs_super_block *sbp = nilfs->ns_sbp[0];
204 nilfs->ns_sbwcount++;
207 * The latest segment becomes trailable from the position
208 * written in superblock.
210 clear_nilfs_discontinued(nilfs);
212 /* update GC protection for recent segments */
213 if (nilfs->ns_sbh[1]) {
214 if (flag == NILFS_SB_COMMIT_ALL) {
215 set_buffer_dirty(nilfs->ns_sbh[1]);
216 if (sync_dirty_buffer(nilfs->ns_sbh[1]) < 0)
219 if (le64_to_cpu(nilfs->ns_sbp[1]->s_last_cno) <
220 le64_to_cpu(nilfs->ns_sbp[0]->s_last_cno))
221 sbp = nilfs->ns_sbp[1];
224 spin_lock(&nilfs->ns_last_segment_lock);
225 nilfs->ns_prot_seq = le64_to_cpu(sbp->s_last_seq);
226 spin_unlock(&nilfs->ns_last_segment_lock);
232 void nilfs_set_log_cursor(struct nilfs_super_block *sbp,
233 struct the_nilfs *nilfs)
235 sector_t nfreeblocks;
237 /* nilfs->ns_sem must be locked by the caller. */
238 nilfs_count_free_blocks(nilfs, &nfreeblocks);
239 sbp->s_free_blocks_count = cpu_to_le64(nfreeblocks);
241 spin_lock(&nilfs->ns_last_segment_lock);
242 sbp->s_last_seq = cpu_to_le64(nilfs->ns_last_seq);
243 sbp->s_last_pseg = cpu_to_le64(nilfs->ns_last_pseg);
244 sbp->s_last_cno = cpu_to_le64(nilfs->ns_last_cno);
245 spin_unlock(&nilfs->ns_last_segment_lock);
248 struct nilfs_super_block **nilfs_prepare_super(struct nilfs_sb_info *sbi,
251 struct the_nilfs *nilfs = sbi->s_nilfs;
252 struct nilfs_super_block **sbp = nilfs->ns_sbp;
254 /* nilfs->ns_sem must be locked by the caller. */
255 if (sbp[0]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) {
257 sbp[1]->s_magic == cpu_to_le16(NILFS_SUPER_MAGIC)) {
258 memcpy(sbp[0], sbp[1], nilfs->ns_sbsize);
260 printk(KERN_CRIT "NILFS: superblock broke on dev %s\n",
265 sbp[1]->s_magic != cpu_to_le16(NILFS_SUPER_MAGIC)) {
266 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
270 nilfs_swap_super_block(nilfs);
275 int nilfs_commit_super(struct nilfs_sb_info *sbi, int flag)
277 struct the_nilfs *nilfs = sbi->s_nilfs;
278 struct nilfs_super_block **sbp = nilfs->ns_sbp;
281 /* nilfs->ns_sem must be locked by the caller. */
283 nilfs->ns_sbwtime = t;
284 sbp[0]->s_wtime = cpu_to_le64(t);
286 sbp[0]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed,
287 (unsigned char *)sbp[0],
289 if (flag == NILFS_SB_COMMIT_ALL && sbp[1]) {
290 sbp[1]->s_wtime = sbp[0]->s_wtime;
292 sbp[1]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed,
293 (unsigned char *)sbp[1],
296 clear_nilfs_sb_dirty(nilfs);
297 return nilfs_sync_super(sbi, flag);
301 * nilfs_cleanup_super() - write filesystem state for cleanup
302 * @sbi: nilfs_sb_info to be unmounted or degraded to read-only
304 * This function restores state flags in the on-disk super block.
305 * This will set "clean" flag (i.e. NILFS_VALID_FS) unless the
306 * filesystem was not clean previously.
308 int nilfs_cleanup_super(struct nilfs_sb_info *sbi)
310 struct nilfs_super_block **sbp;
311 int flag = NILFS_SB_COMMIT;
314 sbp = nilfs_prepare_super(sbi, 0);
316 sbp[0]->s_state = cpu_to_le16(sbi->s_nilfs->ns_mount_state);
317 nilfs_set_log_cursor(sbp[0], sbi->s_nilfs);
318 if (sbp[1] && sbp[0]->s_last_cno == sbp[1]->s_last_cno) {
320 * make the "clean" flag also to the opposite
321 * super block if both super blocks point to
322 * the same checkpoint.
324 sbp[1]->s_state = sbp[0]->s_state;
325 flag = NILFS_SB_COMMIT_ALL;
327 ret = nilfs_commit_super(sbi, flag);
332 static void nilfs_put_super(struct super_block *sb)
334 struct nilfs_sb_info *sbi = NILFS_SB(sb);
335 struct the_nilfs *nilfs = sbi->s_nilfs;
339 nilfs_detach_segment_constructor(sbi);
341 if (!(sb->s_flags & MS_RDONLY)) {
342 down_write(&nilfs->ns_sem);
343 nilfs_cleanup_super(sbi);
344 up_write(&nilfs->ns_sem);
346 down_write(&nilfs->ns_super_sem);
347 if (nilfs->ns_current == sbi)
348 nilfs->ns_current = NULL;
349 up_write(&nilfs->ns_super_sem);
351 nilfs_detach_checkpoint(sbi);
352 put_nilfs(sbi->s_nilfs);
354 sb->s_fs_info = NULL;
355 nilfs_put_sbinfo(sbi);
360 static int nilfs_sync_fs(struct super_block *sb, int wait)
362 struct nilfs_sb_info *sbi = NILFS_SB(sb);
363 struct the_nilfs *nilfs = sbi->s_nilfs;
364 struct nilfs_super_block **sbp;
367 /* This function is called when super block should be written back */
369 err = nilfs_construct_segment(sb);
371 down_write(&nilfs->ns_sem);
372 if (nilfs_sb_dirty(nilfs)) {
373 sbp = nilfs_prepare_super(sbi, nilfs_sb_will_flip(nilfs));
375 nilfs_set_log_cursor(sbp[0], nilfs);
376 nilfs_commit_super(sbi, NILFS_SB_COMMIT);
379 up_write(&nilfs->ns_sem);
384 int nilfs_attach_checkpoint(struct nilfs_sb_info *sbi, __u64 cno)
386 struct the_nilfs *nilfs = sbi->s_nilfs;
387 struct nilfs_checkpoint *raw_cp;
388 struct buffer_head *bh_cp;
391 down_write(&nilfs->ns_super_sem);
392 list_add(&sbi->s_list, &nilfs->ns_supers);
393 up_write(&nilfs->ns_super_sem);
396 sbi->s_ifile = nilfs_ifile_new(sbi, nilfs->ns_inode_size);
400 down_read(&nilfs->ns_segctor_sem);
401 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, cno, 0, &raw_cp,
403 up_read(&nilfs->ns_segctor_sem);
405 if (err == -ENOENT || err == -EINVAL) {
407 "NILFS: Invalid checkpoint "
408 "(checkpoint number=%llu)\n",
409 (unsigned long long)cno);
414 err = nilfs_read_inode_common(sbi->s_ifile, &raw_cp->cp_ifile_inode);
417 atomic_set(&sbi->s_inodes_count, le64_to_cpu(raw_cp->cp_inodes_count));
418 atomic_set(&sbi->s_blocks_count, le64_to_cpu(raw_cp->cp_blocks_count));
420 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp);
424 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp);
426 nilfs_mdt_destroy(sbi->s_ifile);
430 down_write(&nilfs->ns_super_sem);
431 list_del_init(&sbi->s_list);
432 up_write(&nilfs->ns_super_sem);
437 void nilfs_detach_checkpoint(struct nilfs_sb_info *sbi)
439 struct the_nilfs *nilfs = sbi->s_nilfs;
441 nilfs_mdt_destroy(sbi->s_ifile);
443 down_write(&nilfs->ns_super_sem);
444 list_del_init(&sbi->s_list);
445 up_write(&nilfs->ns_super_sem);
448 static int nilfs_statfs(struct dentry *dentry, struct kstatfs *buf)
450 struct super_block *sb = dentry->d_sb;
451 struct nilfs_sb_info *sbi = NILFS_SB(sb);
452 struct the_nilfs *nilfs = sbi->s_nilfs;
453 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
454 unsigned long long blocks;
455 unsigned long overhead;
456 unsigned long nrsvblocks;
457 sector_t nfreeblocks;
461 * Compute all of the segment blocks
463 * The blocks before first segment and after last segment
466 blocks = nilfs->ns_blocks_per_segment * nilfs->ns_nsegments
467 - nilfs->ns_first_data_block;
468 nrsvblocks = nilfs->ns_nrsvsegs * nilfs->ns_blocks_per_segment;
471 * Compute the overhead
473 * When distributing meta data blocks outside segment structure,
474 * We must count them as the overhead.
478 err = nilfs_count_free_blocks(nilfs, &nfreeblocks);
482 buf->f_type = NILFS_SUPER_MAGIC;
483 buf->f_bsize = sb->s_blocksize;
484 buf->f_blocks = blocks - overhead;
485 buf->f_bfree = nfreeblocks;
486 buf->f_bavail = (buf->f_bfree >= nrsvblocks) ?
487 (buf->f_bfree - nrsvblocks) : 0;
488 buf->f_files = atomic_read(&sbi->s_inodes_count);
489 buf->f_ffree = 0; /* nilfs_count_free_inodes(sb); */
490 buf->f_namelen = NILFS_NAME_LEN;
491 buf->f_fsid.val[0] = (u32)id;
492 buf->f_fsid.val[1] = (u32)(id >> 32);
497 static int nilfs_show_options(struct seq_file *seq, struct vfsmount *vfs)
499 struct super_block *sb = vfs->mnt_sb;
500 struct nilfs_sb_info *sbi = NILFS_SB(sb);
502 if (!nilfs_test_opt(sbi, BARRIER))
503 seq_puts(seq, ",nobarrier");
504 if (nilfs_test_opt(sbi, SNAPSHOT))
505 seq_printf(seq, ",cp=%llu",
506 (unsigned long long int)sbi->s_snapshot_cno);
507 if (nilfs_test_opt(sbi, ERRORS_PANIC))
508 seq_puts(seq, ",errors=panic");
509 if (nilfs_test_opt(sbi, ERRORS_CONT))
510 seq_puts(seq, ",errors=continue");
511 if (nilfs_test_opt(sbi, STRICT_ORDER))
512 seq_puts(seq, ",order=strict");
513 if (nilfs_test_opt(sbi, NORECOVERY))
514 seq_puts(seq, ",norecovery");
515 if (nilfs_test_opt(sbi, DISCARD))
516 seq_puts(seq, ",discard");
521 static const struct super_operations nilfs_sops = {
522 .alloc_inode = nilfs_alloc_inode,
523 .destroy_inode = nilfs_destroy_inode,
524 .dirty_inode = nilfs_dirty_inode,
525 /* .write_inode = nilfs_write_inode, */
526 /* .put_inode = nilfs_put_inode, */
527 /* .drop_inode = nilfs_drop_inode, */
528 .evict_inode = nilfs_evict_inode,
529 .put_super = nilfs_put_super,
530 /* .write_super = nilfs_write_super, */
531 .sync_fs = nilfs_sync_fs,
532 /* .write_super_lockfs */
534 .statfs = nilfs_statfs,
535 .remount_fs = nilfs_remount,
537 .show_options = nilfs_show_options
540 static struct inode *
541 nilfs_nfs_get_inode(struct super_block *sb, u64 ino, u32 generation)
545 if (ino < NILFS_FIRST_INO(sb) && ino != NILFS_ROOT_INO &&
546 ino != NILFS_SKETCH_INO)
547 return ERR_PTR(-ESTALE);
549 inode = nilfs_iget(sb, ino);
551 return ERR_CAST(inode);
552 if (generation && inode->i_generation != generation) {
554 return ERR_PTR(-ESTALE);
560 static struct dentry *
561 nilfs_fh_to_dentry(struct super_block *sb, struct fid *fid, int fh_len,
564 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
565 nilfs_nfs_get_inode);
568 static struct dentry *
569 nilfs_fh_to_parent(struct super_block *sb, struct fid *fid, int fh_len,
572 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
573 nilfs_nfs_get_inode);
576 static const struct export_operations nilfs_export_ops = {
577 .fh_to_dentry = nilfs_fh_to_dentry,
578 .fh_to_parent = nilfs_fh_to_parent,
579 .get_parent = nilfs_get_parent,
583 Opt_err_cont, Opt_err_panic, Opt_err_ro,
584 Opt_barrier, Opt_nobarrier, Opt_snapshot, Opt_order, Opt_norecovery,
585 Opt_discard, Opt_nodiscard, Opt_err,
588 static match_table_t tokens = {
589 {Opt_err_cont, "errors=continue"},
590 {Opt_err_panic, "errors=panic"},
591 {Opt_err_ro, "errors=remount-ro"},
592 {Opt_barrier, "barrier"},
593 {Opt_nobarrier, "nobarrier"},
594 {Opt_snapshot, "cp=%u"},
595 {Opt_order, "order=%s"},
596 {Opt_norecovery, "norecovery"},
597 {Opt_discard, "discard"},
598 {Opt_nodiscard, "nodiscard"},
602 static int parse_options(char *options, struct super_block *sb, int is_remount)
604 struct nilfs_sb_info *sbi = NILFS_SB(sb);
606 substring_t args[MAX_OPT_ARGS];
612 while ((p = strsep(&options, ",")) != NULL) {
617 token = match_token(p, tokens, args);
620 nilfs_set_opt(sbi, BARRIER);
623 nilfs_clear_opt(sbi, BARRIER);
626 if (strcmp(args[0].from, "relaxed") == 0)
627 /* Ordered data semantics */
628 nilfs_clear_opt(sbi, STRICT_ORDER);
629 else if (strcmp(args[0].from, "strict") == 0)
630 /* Strict in-order semantics */
631 nilfs_set_opt(sbi, STRICT_ORDER);
636 nilfs_write_opt(sbi, ERROR_MODE, ERRORS_PANIC);
639 nilfs_write_opt(sbi, ERROR_MODE, ERRORS_RO);
642 nilfs_write_opt(sbi, ERROR_MODE, ERRORS_CONT);
645 if (match_int(&args[0], &option) || option <= 0)
648 if (!nilfs_test_opt(sbi, SNAPSHOT)) {
650 "NILFS: cannot change regular "
651 "mount to snapshot.\n");
653 } else if (option != sbi->s_snapshot_cno) {
655 "NILFS: cannot remount to a "
656 "different snapshot.\n");
661 if (!(sb->s_flags & MS_RDONLY)) {
662 printk(KERN_ERR "NILFS: cannot mount snapshot "
663 "read/write. A read-only option is "
667 sbi->s_snapshot_cno = option;
668 nilfs_set_opt(sbi, SNAPSHOT);
671 nilfs_set_opt(sbi, NORECOVERY);
674 nilfs_set_opt(sbi, DISCARD);
677 nilfs_clear_opt(sbi, DISCARD);
681 "NILFS: Unrecognized mount option \"%s\"\n", p);
689 nilfs_set_default_options(struct nilfs_sb_info *sbi,
690 struct nilfs_super_block *sbp)
693 NILFS_MOUNT_ERRORS_RO | NILFS_MOUNT_BARRIER;
696 static int nilfs_setup_super(struct nilfs_sb_info *sbi)
698 struct the_nilfs *nilfs = sbi->s_nilfs;
699 struct nilfs_super_block **sbp;
703 /* nilfs->ns_sem must be locked by the caller. */
704 sbp = nilfs_prepare_super(sbi, 0);
708 max_mnt_count = le16_to_cpu(sbp[0]->s_max_mnt_count);
709 mnt_count = le16_to_cpu(sbp[0]->s_mnt_count);
711 if (nilfs->ns_mount_state & NILFS_ERROR_FS) {
713 "NILFS warning: mounting fs with errors\n");
715 } else if (max_mnt_count >= 0 && mnt_count >= max_mnt_count) {
717 "NILFS warning: maximal mount count reached\n");
721 sbp[0]->s_max_mnt_count = cpu_to_le16(NILFS_DFL_MAX_MNT_COUNT);
723 sbp[0]->s_mnt_count = cpu_to_le16(mnt_count + 1);
725 cpu_to_le16(le16_to_cpu(sbp[0]->s_state) & ~NILFS_VALID_FS);
726 sbp[0]->s_mtime = cpu_to_le64(get_seconds());
727 /* synchronize sbp[1] with sbp[0] */
728 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
729 return nilfs_commit_super(sbi, NILFS_SB_COMMIT_ALL);
732 struct nilfs_super_block *nilfs_read_super_block(struct super_block *sb,
733 u64 pos, int blocksize,
734 struct buffer_head **pbh)
736 unsigned long long sb_index = pos;
737 unsigned long offset;
739 offset = do_div(sb_index, blocksize);
740 *pbh = sb_bread(sb, sb_index);
743 return (struct nilfs_super_block *)((char *)(*pbh)->b_data + offset);
746 int nilfs_store_magic_and_option(struct super_block *sb,
747 struct nilfs_super_block *sbp,
750 struct nilfs_sb_info *sbi = NILFS_SB(sb);
752 sb->s_magic = le16_to_cpu(sbp->s_magic);
754 /* FS independent flags */
755 #ifdef NILFS_ATIME_DISABLE
756 sb->s_flags |= MS_NOATIME;
759 nilfs_set_default_options(sbi, sbp);
761 sbi->s_resuid = le16_to_cpu(sbp->s_def_resuid);
762 sbi->s_resgid = le16_to_cpu(sbp->s_def_resgid);
763 sbi->s_interval = le32_to_cpu(sbp->s_c_interval);
764 sbi->s_watermark = le32_to_cpu(sbp->s_c_block_max);
766 return !parse_options(data, sb, 0) ? -EINVAL : 0 ;
769 int nilfs_check_feature_compatibility(struct super_block *sb,
770 struct nilfs_super_block *sbp)
774 features = le64_to_cpu(sbp->s_feature_incompat) &
775 ~NILFS_FEATURE_INCOMPAT_SUPP;
777 printk(KERN_ERR "NILFS: couldn't mount because of unsupported "
778 "optional features (%llx)\n",
779 (unsigned long long)features);
782 features = le64_to_cpu(sbp->s_feature_compat_ro) &
783 ~NILFS_FEATURE_COMPAT_RO_SUPP;
784 if (!(sb->s_flags & MS_RDONLY) && features) {
785 printk(KERN_ERR "NILFS: couldn't mount RDWR because of "
786 "unsupported optional features (%llx)\n",
787 (unsigned long long)features);
794 * nilfs_fill_super() - initialize a super block instance
796 * @data: mount options
797 * @silent: silent mode flag
798 * @nilfs: the_nilfs struct
800 * This function is called exclusively by nilfs->ns_mount_mutex.
801 * So, the recovery process is protected from other simultaneous mounts.
804 nilfs_fill_super(struct super_block *sb, void *data, int silent,
805 struct the_nilfs *nilfs)
807 struct nilfs_sb_info *sbi;
812 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
819 sbi->s_nilfs = nilfs;
821 atomic_set(&sbi->s_count, 1);
823 err = init_nilfs(nilfs, sbi, (char *)data);
827 spin_lock_init(&sbi->s_inode_lock);
828 INIT_LIST_HEAD(&sbi->s_dirty_files);
829 INIT_LIST_HEAD(&sbi->s_list);
832 * Following initialization is overlapped because
833 * nilfs_sb_info structure has been cleared at the beginning.
834 * But we reserve them to keep our interest and make ready
835 * for the future change.
837 get_random_bytes(&sbi->s_next_generation,
838 sizeof(sbi->s_next_generation));
839 spin_lock_init(&sbi->s_next_gen_lock);
841 sb->s_op = &nilfs_sops;
842 sb->s_export_op = &nilfs_export_ops;
845 sb->s_bdi = nilfs->ns_bdi;
847 err = load_nilfs(nilfs, sbi);
851 cno = nilfs_last_cno(nilfs);
853 if (sb->s_flags & MS_RDONLY) {
854 if (nilfs_test_opt(sbi, SNAPSHOT)) {
855 down_read(&nilfs->ns_segctor_sem);
856 err = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile,
857 sbi->s_snapshot_cno);
858 up_read(&nilfs->ns_segctor_sem);
866 "NILFS: The specified checkpoint is "
868 "(checkpoint number=%llu).\n",
869 (unsigned long long)sbi->s_snapshot_cno);
873 cno = sbi->s_snapshot_cno;
877 err = nilfs_attach_checkpoint(sbi, cno);
879 printk(KERN_ERR "NILFS: error loading a checkpoint"
880 " (checkpoint number=%llu).\n", (unsigned long long)cno);
884 if (!(sb->s_flags & MS_RDONLY)) {
885 err = nilfs_attach_segment_constructor(sbi);
887 goto failed_checkpoint;
890 root = nilfs_iget(sb, NILFS_ROOT_INO);
892 printk(KERN_ERR "NILFS: get root inode failed\n");
896 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
898 printk(KERN_ERR "NILFS: corrupt root inode.\n");
902 sb->s_root = d_alloc_root(root);
905 printk(KERN_ERR "NILFS: get root dentry failed\n");
910 if (!(sb->s_flags & MS_RDONLY)) {
911 down_write(&nilfs->ns_sem);
912 nilfs_setup_super(sbi);
913 up_write(&nilfs->ns_sem);
916 down_write(&nilfs->ns_super_sem);
917 if (!nilfs_test_opt(sbi, SNAPSHOT))
918 nilfs->ns_current = sbi;
919 up_write(&nilfs->ns_super_sem);
924 nilfs_detach_segment_constructor(sbi);
927 nilfs_detach_checkpoint(sbi);
931 sb->s_fs_info = NULL;
932 nilfs_put_sbinfo(sbi);
936 static int nilfs_remount(struct super_block *sb, int *flags, char *data)
938 struct nilfs_sb_info *sbi = NILFS_SB(sb);
939 struct the_nilfs *nilfs = sbi->s_nilfs;
940 unsigned long old_sb_flags;
941 struct nilfs_mount_options old_opts;
942 int was_snapshot, err;
946 down_write(&nilfs->ns_super_sem);
947 old_sb_flags = sb->s_flags;
948 old_opts.mount_opt = sbi->s_mount_opt;
949 old_opts.snapshot_cno = sbi->s_snapshot_cno;
950 was_snapshot = nilfs_test_opt(sbi, SNAPSHOT);
952 if (!parse_options(data, sb, 1)) {
956 sb->s_flags = (sb->s_flags & ~MS_POSIXACL);
959 if (was_snapshot && !(*flags & MS_RDONLY)) {
960 printk(KERN_ERR "NILFS (device %s): cannot remount snapshot "
961 "read/write.\n", sb->s_id);
965 if (!nilfs_valid_fs(nilfs)) {
966 printk(KERN_WARNING "NILFS (device %s): couldn't "
967 "remount because the filesystem is in an "
968 "incomplete recovery state.\n", sb->s_id);
972 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
974 if (*flags & MS_RDONLY) {
975 /* Shutting down the segment constructor */
976 nilfs_detach_segment_constructor(sbi);
977 sb->s_flags |= MS_RDONLY;
980 * Remounting a valid RW partition RDONLY, so set
981 * the RDONLY flag and then mark the partition as valid again.
983 down_write(&nilfs->ns_sem);
984 nilfs_cleanup_super(sbi);
985 up_write(&nilfs->ns_sem);
990 * Mounting a RDONLY partition read-write, so reread and
991 * store the current valid flag. (It may have been changed
992 * by fsck since we originally mounted the partition.)
994 down_read(&nilfs->ns_sem);
995 features = le64_to_cpu(nilfs->ns_sbp[0]->s_feature_compat_ro) &
996 ~NILFS_FEATURE_COMPAT_RO_SUPP;
997 up_read(&nilfs->ns_sem);
999 printk(KERN_WARNING "NILFS (device %s): couldn't "
1000 "remount RDWR because of unsupported optional "
1001 "features (%llx)\n",
1002 sb->s_id, (unsigned long long)features);
1007 sb->s_flags &= ~MS_RDONLY;
1009 err = nilfs_attach_segment_constructor(sbi);
1013 down_write(&nilfs->ns_sem);
1014 nilfs_setup_super(sbi);
1015 up_write(&nilfs->ns_sem);
1018 up_write(&nilfs->ns_super_sem);
1023 sb->s_flags = old_sb_flags;
1024 sbi->s_mount_opt = old_opts.mount_opt;
1025 sbi->s_snapshot_cno = old_opts.snapshot_cno;
1026 up_write(&nilfs->ns_super_sem);
1031 struct nilfs_super_data {
1032 struct block_device *bdev;
1033 struct nilfs_sb_info *sbi;
1039 * nilfs_identify - pre-read mount options needed to identify mount instance
1040 * @data: mount options
1041 * @sd: nilfs_super_data
1043 static int nilfs_identify(char *data, struct nilfs_super_data *sd)
1045 char *p, *options = data;
1046 substring_t args[MAX_OPT_ARGS];
1051 p = strsep(&options, ",");
1052 if (p != NULL && *p) {
1053 token = match_token(p, tokens, args);
1054 if (token == Opt_snapshot) {
1055 if (!(sd->flags & MS_RDONLY))
1058 ret = match_int(&args[0], &option);
1069 "NILFS: invalid mount option: %s\n", p);
1073 BUG_ON(options == data);
1074 *(options - 1) = ',';
1079 static int nilfs_set_bdev_super(struct super_block *s, void *data)
1081 struct nilfs_super_data *sd = data;
1083 s->s_bdev = sd->bdev;
1084 s->s_dev = s->s_bdev->bd_dev;
1088 static int nilfs_test_bdev_super(struct super_block *s, void *data)
1090 struct nilfs_super_data *sd = data;
1092 return sd->sbi && s->s_fs_info == (void *)sd->sbi;
1096 nilfs_get_sb(struct file_system_type *fs_type, int flags,
1097 const char *dev_name, void *data, struct vfsmount *mnt)
1099 struct nilfs_super_data sd;
1100 struct super_block *s;
1101 fmode_t mode = FMODE_READ;
1102 struct the_nilfs *nilfs;
1103 int err, need_to_close = 1;
1105 if (!(flags & MS_RDONLY))
1106 mode |= FMODE_WRITE;
1108 sd.bdev = open_bdev_exclusive(dev_name, mode, fs_type);
1109 if (IS_ERR(sd.bdev))
1110 return PTR_ERR(sd.bdev);
1113 * To get mount instance using sget() vfs-routine, NILFS needs
1114 * much more information than normal filesystems to identify mount
1115 * instance. For snapshot mounts, not only a mount type (ro-mount
1116 * or rw-mount) but also a checkpoint number is required.
1120 if (nilfs_identify((char *)data, &sd)) {
1125 nilfs = find_or_create_nilfs(sd.bdev);
1131 mutex_lock(&nilfs->ns_mount_mutex);
1135 * Check if an exclusive mount exists or not.
1136 * Snapshot mounts coexist with a current mount
1137 * (i.e. rw-mount or ro-mount), whereas rw-mount and
1138 * ro-mount are mutually exclusive.
1140 down_read(&nilfs->ns_super_sem);
1141 if (nilfs->ns_current &&
1142 ((nilfs->ns_current->s_super->s_flags ^ flags)
1144 up_read(&nilfs->ns_super_sem);
1148 up_read(&nilfs->ns_super_sem);
1152 * Find existing nilfs_sb_info struct
1154 sd.sbi = nilfs_find_sbinfo(nilfs, !(flags & MS_RDONLY), sd.cno);
1157 * Get super block instance holding the nilfs_sb_info struct.
1158 * A new instance is allocated if no existing mount is present or
1159 * existing instance has been unmounted.
1161 s = sget(fs_type, nilfs_test_bdev_super, nilfs_set_bdev_super, &sd);
1163 nilfs_put_sbinfo(sd.sbi);
1171 char b[BDEVNAME_SIZE];
1173 /* New superblock instance created */
1176 strlcpy(s->s_id, bdevname(sd.bdev, b), sizeof(s->s_id));
1177 sb_set_blocksize(s, block_size(sd.bdev));
1179 err = nilfs_fill_super(s, data, flags & MS_SILENT ? 1 : 0,
1184 s->s_flags |= MS_ACTIVE;
1188 mutex_unlock(&nilfs->ns_mount_mutex);
1191 close_bdev_exclusive(sd.bdev, mode);
1192 simple_set_mnt(mnt, s);
1196 mutex_unlock(&nilfs->ns_mount_mutex);
1199 close_bdev_exclusive(sd.bdev, mode);
1204 /* Abandoning the newly allocated superblock */
1205 mutex_unlock(&nilfs->ns_mount_mutex);
1207 deactivate_locked_super(s);
1209 * deactivate_locked_super() invokes close_bdev_exclusive().
1210 * We must finish all post-cleaning before this call;
1211 * put_nilfs() needs the block device.
1216 struct file_system_type nilfs_fs_type = {
1217 .owner = THIS_MODULE,
1219 .get_sb = nilfs_get_sb,
1220 .kill_sb = kill_block_super,
1221 .fs_flags = FS_REQUIRES_DEV,
1224 static void nilfs_inode_init_once(void *obj)
1226 struct nilfs_inode_info *ii = obj;
1228 INIT_LIST_HEAD(&ii->i_dirty);
1229 #ifdef CONFIG_NILFS_XATTR
1230 init_rwsem(&ii->xattr_sem);
1232 nilfs_btnode_cache_init_once(&ii->i_btnode_cache);
1233 ii->i_bmap = &ii->i_bmap_data;
1234 inode_init_once(&ii->vfs_inode);
1237 static void nilfs_segbuf_init_once(void *obj)
1239 memset(obj, 0, sizeof(struct nilfs_segment_buffer));
1242 static void nilfs_destroy_cachep(void)
1244 if (nilfs_inode_cachep)
1245 kmem_cache_destroy(nilfs_inode_cachep);
1246 if (nilfs_transaction_cachep)
1247 kmem_cache_destroy(nilfs_transaction_cachep);
1248 if (nilfs_segbuf_cachep)
1249 kmem_cache_destroy(nilfs_segbuf_cachep);
1250 if (nilfs_btree_path_cache)
1251 kmem_cache_destroy(nilfs_btree_path_cache);
1254 static int __init nilfs_init_cachep(void)
1256 nilfs_inode_cachep = kmem_cache_create("nilfs2_inode_cache",
1257 sizeof(struct nilfs_inode_info), 0,
1258 SLAB_RECLAIM_ACCOUNT, nilfs_inode_init_once);
1259 if (!nilfs_inode_cachep)
1262 nilfs_transaction_cachep = kmem_cache_create("nilfs2_transaction_cache",
1263 sizeof(struct nilfs_transaction_info), 0,
1264 SLAB_RECLAIM_ACCOUNT, NULL);
1265 if (!nilfs_transaction_cachep)
1268 nilfs_segbuf_cachep = kmem_cache_create("nilfs2_segbuf_cache",
1269 sizeof(struct nilfs_segment_buffer), 0,
1270 SLAB_RECLAIM_ACCOUNT, nilfs_segbuf_init_once);
1271 if (!nilfs_segbuf_cachep)
1274 nilfs_btree_path_cache = kmem_cache_create("nilfs2_btree_path_cache",
1275 sizeof(struct nilfs_btree_path) * NILFS_BTREE_LEVEL_MAX,
1277 if (!nilfs_btree_path_cache)
1283 nilfs_destroy_cachep();
1287 static int __init init_nilfs_fs(void)
1291 err = nilfs_init_cachep();
1295 err = register_filesystem(&nilfs_fs_type);
1299 printk(KERN_INFO "NILFS version 2 loaded\n");
1303 nilfs_destroy_cachep();
1308 static void __exit exit_nilfs_fs(void)
1310 nilfs_destroy_cachep();
1311 unregister_filesystem(&nilfs_fs_type);
1314 module_init(init_nilfs_fs)
1315 module_exit(exit_nilfs_fs)