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>
65 MODULE_AUTHOR("NTT Corp.");
66 MODULE_DESCRIPTION("A New Implementation of the Log-structured Filesystem "
68 MODULE_LICENSE("GPL");
70 static int nilfs_remount(struct super_block *sb, int *flags, char *data);
73 * nilfs_error() - report failure condition on a filesystem
75 * nilfs_error() sets an ERROR_FS flag on the superblock as well as
76 * reporting an error message. It should be called when NILFS detects
77 * incoherences or defects of meta data on disk. As for sustainable
78 * errors such as a single-shot I/O error, nilfs_warning() or the printk()
79 * function should be used instead.
81 * The segment constructor must not call this function because it can
84 void nilfs_error(struct super_block *sb, const char *function,
87 struct nilfs_sb_info *sbi = NILFS_SB(sb);
91 printk(KERN_CRIT "NILFS error (device %s): %s: ", sb->s_id, function);
96 if (!(sb->s_flags & MS_RDONLY)) {
97 struct the_nilfs *nilfs = sbi->s_nilfs;
99 if (!nilfs_test_opt(sbi, ERRORS_CONT))
100 nilfs_detach_segment_constructor(sbi);
102 down_write(&nilfs->ns_sem);
103 if (!(nilfs->ns_mount_state & NILFS_ERROR_FS)) {
104 nilfs->ns_mount_state |= NILFS_ERROR_FS;
105 nilfs->ns_sbp[0]->s_state |=
106 cpu_to_le16(NILFS_ERROR_FS);
107 nilfs_commit_super(sbi, 1);
109 up_write(&nilfs->ns_sem);
111 if (nilfs_test_opt(sbi, ERRORS_RO)) {
112 printk(KERN_CRIT "Remounting filesystem read-only\n");
113 sb->s_flags |= MS_RDONLY;
117 if (nilfs_test_opt(sbi, ERRORS_PANIC))
118 panic("NILFS (device %s): panic forced after error\n",
122 void nilfs_warning(struct super_block *sb, const char *function,
123 const char *fmt, ...)
128 printk(KERN_WARNING "NILFS warning (device %s): %s: ",
135 static struct kmem_cache *nilfs_inode_cachep;
137 struct inode *nilfs_alloc_inode_common(struct the_nilfs *nilfs)
139 struct nilfs_inode_info *ii;
141 ii = kmem_cache_alloc(nilfs_inode_cachep, GFP_NOFS);
146 ii->vfs_inode.i_version = 1;
147 nilfs_btnode_cache_init(&ii->i_btnode_cache, nilfs->ns_bdi);
148 return &ii->vfs_inode;
151 struct inode *nilfs_alloc_inode(struct super_block *sb)
153 return nilfs_alloc_inode_common(NILFS_SB(sb)->s_nilfs);
156 void nilfs_destroy_inode(struct inode *inode)
158 kmem_cache_free(nilfs_inode_cachep, NILFS_I(inode));
161 static void init_once(void *obj)
163 struct nilfs_inode_info *ii = obj;
165 INIT_LIST_HEAD(&ii->i_dirty);
166 #ifdef CONFIG_NILFS_XATTR
167 init_rwsem(&ii->xattr_sem);
169 nilfs_btnode_cache_init_once(&ii->i_btnode_cache);
170 ii->i_bmap = (struct nilfs_bmap *)&ii->i_bmap_union;
171 inode_init_once(&ii->vfs_inode);
174 static int nilfs_init_inode_cache(void)
176 nilfs_inode_cachep = kmem_cache_create("nilfs2_inode_cache",
177 sizeof(struct nilfs_inode_info),
178 0, SLAB_RECLAIM_ACCOUNT,
181 return (nilfs_inode_cachep == NULL) ? -ENOMEM : 0;
184 static inline void nilfs_destroy_inode_cache(void)
186 kmem_cache_destroy(nilfs_inode_cachep);
189 static void nilfs_clear_inode(struct inode *inode)
191 struct nilfs_inode_info *ii = NILFS_I(inode);
194 * Free resources allocated in nilfs_read_inode(), here.
196 BUG_ON(!list_empty(&ii->i_dirty));
200 if (test_bit(NILFS_I_BMAP, &ii->i_state))
201 nilfs_bmap_clear(ii->i_bmap);
203 nilfs_btnode_cache_clear(&ii->i_btnode_cache);
206 static int nilfs_sync_super(struct nilfs_sb_info *sbi, int dupsb)
208 struct the_nilfs *nilfs = sbi->s_nilfs;
210 int barrier_done = 0;
212 if (nilfs_test_opt(sbi, BARRIER)) {
213 set_buffer_ordered(nilfs->ns_sbh[0]);
217 set_buffer_dirty(nilfs->ns_sbh[0]);
218 err = sync_dirty_buffer(nilfs->ns_sbh[0]);
219 if (err == -EOPNOTSUPP && barrier_done) {
220 nilfs_warning(sbi->s_super, __func__,
221 "barrier-based sync failed. "
222 "disabling barriers\n");
223 nilfs_clear_opt(sbi, BARRIER);
225 clear_buffer_ordered(nilfs->ns_sbh[0]);
230 "NILFS: unable to write superblock (err=%d)\n", err);
231 if (err == -EIO && nilfs->ns_sbh[1]) {
232 nilfs_fall_back_super_block(nilfs);
236 struct nilfs_super_block *sbp = nilfs->ns_sbp[0];
239 * The latest segment becomes trailable from the position
240 * written in superblock.
242 clear_nilfs_discontinued(nilfs);
244 /* update GC protection for recent segments */
245 if (nilfs->ns_sbh[1]) {
248 set_buffer_dirty(nilfs->ns_sbh[1]);
249 if (!sync_dirty_buffer(nilfs->ns_sbh[1]))
250 sbp = nilfs->ns_sbp[1];
254 spin_lock(&nilfs->ns_last_segment_lock);
255 nilfs->ns_prot_seq = le64_to_cpu(sbp->s_last_seq);
256 spin_unlock(&nilfs->ns_last_segment_lock);
263 int nilfs_commit_super(struct nilfs_sb_info *sbi, int dupsb)
265 struct the_nilfs *nilfs = sbi->s_nilfs;
266 struct nilfs_super_block **sbp = nilfs->ns_sbp;
267 sector_t nfreeblocks;
271 /* nilfs->sem must be locked by the caller. */
272 if (sbp[0]->s_magic != NILFS_SUPER_MAGIC) {
273 if (sbp[1] && sbp[1]->s_magic == NILFS_SUPER_MAGIC)
274 nilfs_swap_super_block(nilfs);
276 printk(KERN_CRIT "NILFS: superblock broke on dev %s\n",
281 err = nilfs_count_free_blocks(nilfs, &nfreeblocks);
283 printk(KERN_ERR "NILFS: failed to count free blocks\n");
286 spin_lock(&nilfs->ns_last_segment_lock);
287 sbp[0]->s_last_seq = cpu_to_le64(nilfs->ns_last_seq);
288 sbp[0]->s_last_pseg = cpu_to_le64(nilfs->ns_last_pseg);
289 sbp[0]->s_last_cno = cpu_to_le64(nilfs->ns_last_cno);
290 spin_unlock(&nilfs->ns_last_segment_lock);
293 nilfs->ns_sbwtime[0] = t;
294 sbp[0]->s_free_blocks_count = cpu_to_le64(nfreeblocks);
295 sbp[0]->s_wtime = cpu_to_le64(t);
297 sbp[0]->s_sum = cpu_to_le32(crc32_le(nilfs->ns_crc_seed,
298 (unsigned char *)sbp[0],
300 if (dupsb && sbp[1]) {
301 memcpy(sbp[1], sbp[0], nilfs->ns_sbsize);
302 nilfs->ns_sbwtime[1] = t;
304 sbi->s_super->s_dirt = 0;
305 return nilfs_sync_super(sbi, dupsb);
308 static void nilfs_put_super(struct super_block *sb)
310 struct nilfs_sb_info *sbi = NILFS_SB(sb);
311 struct the_nilfs *nilfs = sbi->s_nilfs;
315 nilfs_detach_segment_constructor(sbi);
317 if (!(sb->s_flags & MS_RDONLY)) {
318 down_write(&nilfs->ns_sem);
319 nilfs->ns_sbp[0]->s_state = cpu_to_le16(nilfs->ns_mount_state);
320 nilfs_commit_super(sbi, 1);
321 up_write(&nilfs->ns_sem);
323 down_write(&nilfs->ns_super_sem);
324 if (nilfs->ns_current == sbi)
325 nilfs->ns_current = NULL;
326 up_write(&nilfs->ns_super_sem);
328 nilfs_detach_checkpoint(sbi);
329 put_nilfs(sbi->s_nilfs);
331 sb->s_fs_info = NULL;
332 nilfs_put_sbinfo(sbi);
337 static int nilfs_sync_fs(struct super_block *sb, int wait)
339 struct nilfs_sb_info *sbi = NILFS_SB(sb);
340 struct the_nilfs *nilfs = sbi->s_nilfs;
343 /* This function is called when super block should be written back */
345 err = nilfs_construct_segment(sb);
347 down_write(&nilfs->ns_sem);
349 nilfs_commit_super(sbi, 1);
350 up_write(&nilfs->ns_sem);
355 int nilfs_attach_checkpoint(struct nilfs_sb_info *sbi, __u64 cno)
357 struct the_nilfs *nilfs = sbi->s_nilfs;
358 struct nilfs_checkpoint *raw_cp;
359 struct buffer_head *bh_cp;
362 down_write(&nilfs->ns_super_sem);
363 list_add(&sbi->s_list, &nilfs->ns_supers);
364 up_write(&nilfs->ns_super_sem);
366 sbi->s_ifile = nilfs_mdt_new(
367 nilfs, sbi->s_super, NILFS_IFILE_INO, NILFS_IFILE_GFP);
371 err = nilfs_palloc_init_blockgroup(sbi->s_ifile, nilfs->ns_inode_size);
375 down_read(&nilfs->ns_segctor_sem);
376 err = nilfs_cpfile_get_checkpoint(nilfs->ns_cpfile, cno, 0, &raw_cp,
378 up_read(&nilfs->ns_segctor_sem);
380 if (err == -ENOENT || err == -EINVAL) {
382 "NILFS: Invalid checkpoint "
383 "(checkpoint number=%llu)\n",
384 (unsigned long long)cno);
389 err = nilfs_read_inode_common(sbi->s_ifile, &raw_cp->cp_ifile_inode);
392 atomic_set(&sbi->s_inodes_count, le64_to_cpu(raw_cp->cp_inodes_count));
393 atomic_set(&sbi->s_blocks_count, le64_to_cpu(raw_cp->cp_blocks_count));
395 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp);
399 nilfs_cpfile_put_checkpoint(nilfs->ns_cpfile, cno, bh_cp);
401 nilfs_mdt_destroy(sbi->s_ifile);
404 down_write(&nilfs->ns_super_sem);
405 list_del_init(&sbi->s_list);
406 up_write(&nilfs->ns_super_sem);
411 void nilfs_detach_checkpoint(struct nilfs_sb_info *sbi)
413 struct the_nilfs *nilfs = sbi->s_nilfs;
415 nilfs_mdt_clear(sbi->s_ifile);
416 nilfs_mdt_destroy(sbi->s_ifile);
418 down_write(&nilfs->ns_super_sem);
419 list_del_init(&sbi->s_list);
420 up_write(&nilfs->ns_super_sem);
423 static int nilfs_mark_recovery_complete(struct nilfs_sb_info *sbi)
425 struct the_nilfs *nilfs = sbi->s_nilfs;
428 down_write(&nilfs->ns_sem);
429 if (!(nilfs->ns_mount_state & NILFS_VALID_FS)) {
430 nilfs->ns_mount_state |= NILFS_VALID_FS;
431 err = nilfs_commit_super(sbi, 1);
433 printk(KERN_INFO "NILFS: recovery complete.\n");
435 up_write(&nilfs->ns_sem);
439 static int nilfs_statfs(struct dentry *dentry, struct kstatfs *buf)
441 struct super_block *sb = dentry->d_sb;
442 struct nilfs_sb_info *sbi = NILFS_SB(sb);
443 struct the_nilfs *nilfs = sbi->s_nilfs;
444 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
445 unsigned long long blocks;
446 unsigned long overhead;
447 unsigned long nrsvblocks;
448 sector_t nfreeblocks;
452 * Compute all of the segment blocks
454 * The blocks before first segment and after last segment
457 blocks = nilfs->ns_blocks_per_segment * nilfs->ns_nsegments
458 - nilfs->ns_first_data_block;
459 nrsvblocks = nilfs->ns_nrsvsegs * nilfs->ns_blocks_per_segment;
462 * Compute the overhead
464 * When distributing meta data blocks outside semgent structure,
465 * We must count them as the overhead.
469 err = nilfs_count_free_blocks(nilfs, &nfreeblocks);
473 buf->f_type = NILFS_SUPER_MAGIC;
474 buf->f_bsize = sb->s_blocksize;
475 buf->f_blocks = blocks - overhead;
476 buf->f_bfree = nfreeblocks;
477 buf->f_bavail = (buf->f_bfree >= nrsvblocks) ?
478 (buf->f_bfree - nrsvblocks) : 0;
479 buf->f_files = atomic_read(&sbi->s_inodes_count);
480 buf->f_ffree = 0; /* nilfs_count_free_inodes(sb); */
481 buf->f_namelen = NILFS_NAME_LEN;
482 buf->f_fsid.val[0] = (u32)id;
483 buf->f_fsid.val[1] = (u32)(id >> 32);
488 static int nilfs_show_options(struct seq_file *seq, struct vfsmount *vfs)
490 struct super_block *sb = vfs->mnt_sb;
491 struct nilfs_sb_info *sbi = NILFS_SB(sb);
493 if (!nilfs_test_opt(sbi, BARRIER))
494 seq_printf(seq, ",barrier=off");
495 if (nilfs_test_opt(sbi, SNAPSHOT))
496 seq_printf(seq, ",cp=%llu",
497 (unsigned long long int)sbi->s_snapshot_cno);
498 if (nilfs_test_opt(sbi, ERRORS_RO))
499 seq_printf(seq, ",errors=remount-ro");
500 if (nilfs_test_opt(sbi, ERRORS_PANIC))
501 seq_printf(seq, ",errors=panic");
502 if (nilfs_test_opt(sbi, STRICT_ORDER))
503 seq_printf(seq, ",order=strict");
508 static struct super_operations nilfs_sops = {
509 .alloc_inode = nilfs_alloc_inode,
510 .destroy_inode = nilfs_destroy_inode,
511 .dirty_inode = nilfs_dirty_inode,
512 /* .write_inode = nilfs_write_inode, */
513 /* .put_inode = nilfs_put_inode, */
514 /* .drop_inode = nilfs_drop_inode, */
515 .delete_inode = nilfs_delete_inode,
516 .put_super = nilfs_put_super,
517 /* .write_super = nilfs_write_super, */
518 .sync_fs = nilfs_sync_fs,
519 /* .write_super_lockfs */
521 .statfs = nilfs_statfs,
522 .remount_fs = nilfs_remount,
523 .clear_inode = nilfs_clear_inode,
525 .show_options = nilfs_show_options
528 static struct inode *
529 nilfs_nfs_get_inode(struct super_block *sb, u64 ino, u32 generation)
533 if (ino < NILFS_FIRST_INO(sb) && ino != NILFS_ROOT_INO &&
534 ino != NILFS_SKETCH_INO)
535 return ERR_PTR(-ESTALE);
537 inode = nilfs_iget(sb, ino);
539 return ERR_CAST(inode);
540 if (generation && inode->i_generation != generation) {
542 return ERR_PTR(-ESTALE);
548 static struct dentry *
549 nilfs_fh_to_dentry(struct super_block *sb, struct fid *fid, int fh_len,
552 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
553 nilfs_nfs_get_inode);
556 static struct dentry *
557 nilfs_fh_to_parent(struct super_block *sb, struct fid *fid, int fh_len,
560 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
561 nilfs_nfs_get_inode);
564 static struct export_operations nilfs_export_ops = {
565 .fh_to_dentry = nilfs_fh_to_dentry,
566 .fh_to_parent = nilfs_fh_to_parent,
567 .get_parent = nilfs_get_parent,
571 Opt_err_cont, Opt_err_panic, Opt_err_ro,
572 Opt_barrier, Opt_snapshot, Opt_order,
576 static match_table_t tokens = {
577 {Opt_err_cont, "errors=continue"},
578 {Opt_err_panic, "errors=panic"},
579 {Opt_err_ro, "errors=remount-ro"},
580 {Opt_barrier, "barrier=%s"},
581 {Opt_snapshot, "cp=%u"},
582 {Opt_order, "order=%s"},
586 static int match_bool(substring_t *s, int *result)
588 int len = s->to - s->from;
590 if (strncmp(s->from, "on", len) == 0)
592 else if (strncmp(s->from, "off", len) == 0)
599 static int parse_options(char *options, struct super_block *sb)
601 struct nilfs_sb_info *sbi = NILFS_SB(sb);
603 substring_t args[MAX_OPT_ARGS];
609 while ((p = strsep(&options, ",")) != NULL) {
614 token = match_token(p, tokens, args);
617 if (match_bool(&args[0], &option))
620 nilfs_set_opt(sbi, BARRIER);
622 nilfs_clear_opt(sbi, BARRIER);
625 if (strcmp(args[0].from, "relaxed") == 0)
626 /* Ordered data semantics */
627 nilfs_clear_opt(sbi, STRICT_ORDER);
628 else if (strcmp(args[0].from, "strict") == 0)
629 /* Strict in-order semantics */
630 nilfs_set_opt(sbi, STRICT_ORDER);
635 nilfs_write_opt(sbi, ERROR_MODE, ERRORS_PANIC);
638 nilfs_write_opt(sbi, ERROR_MODE, ERRORS_RO);
641 nilfs_write_opt(sbi, ERROR_MODE, ERRORS_CONT);
644 if (match_int(&args[0], &option) || option <= 0)
646 if (!(sb->s_flags & MS_RDONLY))
648 sbi->s_snapshot_cno = option;
649 nilfs_set_opt(sbi, SNAPSHOT);
653 "NILFS: Unrecognized mount option \"%s\"\n", p);
661 nilfs_set_default_options(struct nilfs_sb_info *sbi,
662 struct nilfs_super_block *sbp)
665 NILFS_MOUNT_ERRORS_CONT | NILFS_MOUNT_BARRIER;
668 static int nilfs_setup_super(struct nilfs_sb_info *sbi)
670 struct the_nilfs *nilfs = sbi->s_nilfs;
671 struct nilfs_super_block *sbp = nilfs->ns_sbp[0];
672 int max_mnt_count = le16_to_cpu(sbp->s_max_mnt_count);
673 int mnt_count = le16_to_cpu(sbp->s_mnt_count);
675 /* nilfs->sem must be locked by the caller. */
676 if (!(nilfs->ns_mount_state & NILFS_VALID_FS)) {
677 printk(KERN_WARNING "NILFS warning: mounting unchecked fs\n");
678 } else if (nilfs->ns_mount_state & NILFS_ERROR_FS) {
680 "NILFS warning: mounting fs with errors\n");
682 } else if (max_mnt_count >= 0 && mnt_count >= max_mnt_count) {
684 "NILFS warning: maximal mount count reached\n");
688 sbp->s_max_mnt_count = cpu_to_le16(NILFS_DFL_MAX_MNT_COUNT);
690 sbp->s_mnt_count = cpu_to_le16(mnt_count + 1);
691 sbp->s_state = cpu_to_le16(le16_to_cpu(sbp->s_state) & ~NILFS_VALID_FS);
692 sbp->s_mtime = cpu_to_le64(get_seconds());
693 return nilfs_commit_super(sbi, 1);
696 struct nilfs_super_block *nilfs_read_super_block(struct super_block *sb,
697 u64 pos, int blocksize,
698 struct buffer_head **pbh)
700 unsigned long long sb_index = pos;
701 unsigned long offset;
703 offset = do_div(sb_index, blocksize);
704 *pbh = sb_bread(sb, sb_index);
707 return (struct nilfs_super_block *)((char *)(*pbh)->b_data + offset);
710 int nilfs_store_magic_and_option(struct super_block *sb,
711 struct nilfs_super_block *sbp,
714 struct nilfs_sb_info *sbi = NILFS_SB(sb);
716 sb->s_magic = le16_to_cpu(sbp->s_magic);
718 /* FS independent flags */
719 #ifdef NILFS_ATIME_DISABLE
720 sb->s_flags |= MS_NOATIME;
723 nilfs_set_default_options(sbi, sbp);
725 sbi->s_resuid = le16_to_cpu(sbp->s_def_resuid);
726 sbi->s_resgid = le16_to_cpu(sbp->s_def_resgid);
727 sbi->s_interval = le32_to_cpu(sbp->s_c_interval);
728 sbi->s_watermark = le32_to_cpu(sbp->s_c_block_max);
730 return !parse_options(data, sb) ? -EINVAL : 0 ;
734 * nilfs_fill_super() - initialize a super block instance
736 * @data: mount options
737 * @silent: silent mode flag
738 * @nilfs: the_nilfs struct
740 * This function is called exclusively by nilfs->ns_mount_mutex.
741 * So, the recovery process is protected from other simultaneous mounts.
744 nilfs_fill_super(struct super_block *sb, void *data, int silent,
745 struct the_nilfs *nilfs)
747 struct nilfs_sb_info *sbi;
752 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
759 sbi->s_nilfs = nilfs;
761 atomic_set(&sbi->s_count, 1);
763 err = init_nilfs(nilfs, sbi, (char *)data);
767 spin_lock_init(&sbi->s_inode_lock);
768 INIT_LIST_HEAD(&sbi->s_dirty_files);
769 INIT_LIST_HEAD(&sbi->s_list);
772 * Following initialization is overlapped because
773 * nilfs_sb_info structure has been cleared at the beginning.
774 * But we reserve them to keep our interest and make ready
775 * for the future change.
777 get_random_bytes(&sbi->s_next_generation,
778 sizeof(sbi->s_next_generation));
779 spin_lock_init(&sbi->s_next_gen_lock);
781 sb->s_op = &nilfs_sops;
782 sb->s_export_op = &nilfs_export_ops;
786 if (!nilfs_loaded(nilfs)) {
787 err = load_nilfs(nilfs, sbi);
791 cno = nilfs_last_cno(nilfs);
793 if (sb->s_flags & MS_RDONLY) {
794 if (nilfs_test_opt(sbi, SNAPSHOT)) {
795 down_read(&nilfs->ns_segctor_sem);
796 err = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile,
797 sbi->s_snapshot_cno);
798 up_read(&nilfs->ns_segctor_sem);
806 "NILFS: The specified checkpoint is "
808 "(checkpoint number=%llu).\n",
809 (unsigned long long)sbi->s_snapshot_cno);
813 cno = sbi->s_snapshot_cno;
815 /* Read-only mount */
816 sbi->s_snapshot_cno = cno;
819 err = nilfs_attach_checkpoint(sbi, cno);
821 printk(KERN_ERR "NILFS: error loading a checkpoint"
822 " (checkpoint number=%llu).\n", (unsigned long long)cno);
826 if (!(sb->s_flags & MS_RDONLY)) {
827 err = nilfs_attach_segment_constructor(sbi);
829 goto failed_checkpoint;
832 root = nilfs_iget(sb, NILFS_ROOT_INO);
834 printk(KERN_ERR "NILFS: get root inode failed\n");
838 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
840 printk(KERN_ERR "NILFS: corrupt root inode.\n");
844 sb->s_root = d_alloc_root(root);
847 printk(KERN_ERR "NILFS: get root dentry failed\n");
852 if (!(sb->s_flags & MS_RDONLY)) {
853 down_write(&nilfs->ns_sem);
854 nilfs_setup_super(sbi);
855 up_write(&nilfs->ns_sem);
858 err = nilfs_mark_recovery_complete(sbi);
860 printk(KERN_ERR "NILFS: recovery failed.\n");
864 down_write(&nilfs->ns_super_sem);
865 if (!nilfs_test_opt(sbi, SNAPSHOT))
866 nilfs->ns_current = sbi;
867 up_write(&nilfs->ns_super_sem);
876 nilfs_detach_segment_constructor(sbi);
879 nilfs_detach_checkpoint(sbi);
883 sb->s_fs_info = NULL;
884 nilfs_put_sbinfo(sbi);
888 static int nilfs_remount(struct super_block *sb, int *flags, char *data)
890 struct nilfs_sb_info *sbi = NILFS_SB(sb);
891 struct nilfs_super_block *sbp;
892 struct the_nilfs *nilfs = sbi->s_nilfs;
893 unsigned long old_sb_flags;
894 struct nilfs_mount_options old_opts;
899 down_write(&nilfs->ns_super_sem);
900 old_sb_flags = sb->s_flags;
901 old_opts.mount_opt = sbi->s_mount_opt;
902 old_opts.snapshot_cno = sbi->s_snapshot_cno;
904 if (!parse_options(data, sb)) {
908 sb->s_flags = (sb->s_flags & ~MS_POSIXACL);
910 if ((*flags & MS_RDONLY) &&
911 sbi->s_snapshot_cno != old_opts.snapshot_cno) {
912 printk(KERN_WARNING "NILFS (device %s): couldn't "
913 "remount to a different snapshot. \n",
919 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
921 if (*flags & MS_RDONLY) {
922 /* Shutting down the segment constructor */
923 nilfs_detach_segment_constructor(sbi);
924 sb->s_flags |= MS_RDONLY;
926 sbi->s_snapshot_cno = nilfs_last_cno(nilfs);
927 /* nilfs_set_opt(sbi, SNAPSHOT); */
930 * Remounting a valid RW partition RDONLY, so set
931 * the RDONLY flag and then mark the partition as valid again.
933 down_write(&nilfs->ns_sem);
934 sbp = nilfs->ns_sbp[0];
935 if (!(sbp->s_state & le16_to_cpu(NILFS_VALID_FS)) &&
936 (nilfs->ns_mount_state & NILFS_VALID_FS))
937 sbp->s_state = cpu_to_le16(nilfs->ns_mount_state);
938 sbp->s_mtime = cpu_to_le64(get_seconds());
939 nilfs_commit_super(sbi, 1);
940 up_write(&nilfs->ns_sem);
943 * Mounting a RDONLY partition read-write, so reread and
944 * store the current valid flag. (It may have been changed
945 * by fsck since we originally mounted the partition.)
947 if (nilfs->ns_current && nilfs->ns_current != sbi) {
948 printk(KERN_WARNING "NILFS (device %s): couldn't "
949 "remount because an RW-mount exists.\n",
954 if (sbi->s_snapshot_cno != nilfs_last_cno(nilfs)) {
955 printk(KERN_WARNING "NILFS (device %s): couldn't "
956 "remount because the current RO-mount is not "
962 sb->s_flags &= ~MS_RDONLY;
963 nilfs_clear_opt(sbi, SNAPSHOT);
964 sbi->s_snapshot_cno = 0;
966 err = nilfs_attach_segment_constructor(sbi);
970 down_write(&nilfs->ns_sem);
971 nilfs_setup_super(sbi);
972 up_write(&nilfs->ns_sem);
974 nilfs->ns_current = sbi;
977 up_write(&nilfs->ns_super_sem);
982 sb->s_flags = old_sb_flags;
983 sbi->s_mount_opt = old_opts.mount_opt;
984 sbi->s_snapshot_cno = old_opts.snapshot_cno;
985 up_write(&nilfs->ns_super_sem);
990 struct nilfs_super_data {
991 struct block_device *bdev;
992 struct nilfs_sb_info *sbi;
998 * nilfs_identify - pre-read mount options needed to identify mount instance
999 * @data: mount options
1000 * @sd: nilfs_super_data
1002 static int nilfs_identify(char *data, struct nilfs_super_data *sd)
1004 char *p, *options = data;
1005 substring_t args[MAX_OPT_ARGS];
1010 p = strsep(&options, ",");
1011 if (p != NULL && *p) {
1012 token = match_token(p, tokens, args);
1013 if (token == Opt_snapshot) {
1014 if (!(sd->flags & MS_RDONLY))
1017 ret = match_int(&args[0], &option);
1028 "NILFS: invalid mount option: %s\n", p);
1032 BUG_ON(options == data);
1033 *(options - 1) = ',';
1038 static int nilfs_set_bdev_super(struct super_block *s, void *data)
1040 struct nilfs_super_data *sd = data;
1042 s->s_bdev = sd->bdev;
1043 s->s_dev = s->s_bdev->bd_dev;
1047 static int nilfs_test_bdev_super(struct super_block *s, void *data)
1049 struct nilfs_super_data *sd = data;
1051 return sd->sbi && s->s_fs_info == (void *)sd->sbi;
1055 nilfs_get_sb(struct file_system_type *fs_type, int flags,
1056 const char *dev_name, void *data, struct vfsmount *mnt)
1058 struct nilfs_super_data sd;
1059 struct super_block *s;
1060 struct the_nilfs *nilfs;
1061 int err, need_to_close = 1;
1063 sd.bdev = open_bdev_exclusive(dev_name, flags, fs_type);
1064 if (IS_ERR(sd.bdev))
1065 return PTR_ERR(sd.bdev);
1068 * To get mount instance using sget() vfs-routine, NILFS needs
1069 * much more information than normal filesystems to identify mount
1070 * instance. For snapshot mounts, not only a mount type (ro-mount
1071 * or rw-mount) but also a checkpoint number is required.
1075 if (nilfs_identify((char *)data, &sd)) {
1080 nilfs = find_or_create_nilfs(sd.bdev);
1086 mutex_lock(&nilfs->ns_mount_mutex);
1090 * Check if an exclusive mount exists or not.
1091 * Snapshot mounts coexist with a current mount
1092 * (i.e. rw-mount or ro-mount), whereas rw-mount and
1093 * ro-mount are mutually exclusive.
1095 down_read(&nilfs->ns_super_sem);
1096 if (nilfs->ns_current &&
1097 ((nilfs->ns_current->s_super->s_flags ^ flags)
1099 up_read(&nilfs->ns_super_sem);
1103 up_read(&nilfs->ns_super_sem);
1107 * Find existing nilfs_sb_info struct
1109 sd.sbi = nilfs_find_sbinfo(nilfs, !(flags & MS_RDONLY), sd.cno);
1112 * Get super block instance holding the nilfs_sb_info struct.
1113 * A new instance is allocated if no existing mount is present or
1114 * existing instance has been unmounted.
1116 s = sget(fs_type, nilfs_test_bdev_super, nilfs_set_bdev_super, &sd);
1118 nilfs_put_sbinfo(sd.sbi);
1126 char b[BDEVNAME_SIZE];
1128 /* New superblock instance created */
1130 strlcpy(s->s_id, bdevname(sd.bdev, b), sizeof(s->s_id));
1131 sb_set_blocksize(s, block_size(sd.bdev));
1133 err = nilfs_fill_super(s, data, flags & MS_VERBOSE, nilfs);
1137 s->s_flags |= MS_ACTIVE;
1141 mutex_unlock(&nilfs->ns_mount_mutex);
1144 close_bdev_exclusive(sd.bdev, flags);
1145 simple_set_mnt(mnt, s);
1149 mutex_unlock(&nilfs->ns_mount_mutex);
1152 close_bdev_exclusive(sd.bdev, flags);
1157 /* Abandoning the newly allocated superblock */
1158 mutex_unlock(&nilfs->ns_mount_mutex);
1160 up_write(&s->s_umount);
1161 deactivate_super(s);
1163 * deactivate_super() invokes close_bdev_exclusive().
1164 * We must finish all post-cleaning before this call;
1165 * put_nilfs() needs the block device.
1170 struct file_system_type nilfs_fs_type = {
1171 .owner = THIS_MODULE,
1173 .get_sb = nilfs_get_sb,
1174 .kill_sb = kill_block_super,
1175 .fs_flags = FS_REQUIRES_DEV,
1178 static int __init init_nilfs_fs(void)
1182 err = nilfs_init_inode_cache();
1186 err = nilfs_init_transaction_cache();
1188 goto failed_inode_cache;
1190 err = nilfs_init_segbuf_cache();
1192 goto failed_transaction_cache;
1194 err = nilfs_btree_path_cache_init();
1196 goto failed_segbuf_cache;
1198 err = register_filesystem(&nilfs_fs_type);
1200 goto failed_btree_path_cache;
1204 failed_btree_path_cache:
1205 nilfs_btree_path_cache_destroy();
1207 failed_segbuf_cache:
1208 nilfs_destroy_segbuf_cache();
1210 failed_transaction_cache:
1211 nilfs_destroy_transaction_cache();
1214 nilfs_destroy_inode_cache();
1220 static void __exit exit_nilfs_fs(void)
1222 nilfs_destroy_segbuf_cache();
1223 nilfs_destroy_transaction_cache();
1224 nilfs_destroy_inode_cache();
1225 nilfs_btree_path_cache_destroy();
1226 unregister_filesystem(&nilfs_fs_type);
1229 module_init(init_nilfs_fs)
1230 module_exit(exit_nilfs_fs)