/**
* nilfs_fill_super() - initialize a super block instance
* @sb: super_block
* @data: mount options
* @silent: silent mode flag
*
* This function is called exclusively by nilfs->ns_mount_mutex.
* So, the recovery process is protected from other simultaneous mounts.
*/
static int
nilfs_fill_super(struct super_block *sb, void *data, int silent)
{
struct the_nilfs *nilfs;
struct nilfs_sb_info *sbi;
struct nilfs_root *fsroot;
struct backing_dev_info *bdi;
__u64 cno;
int err;
sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
if (!sbi)
return -ENOMEM;
sb->s_fs_info = sbi;
sbi->s_super = sb;
nilfs = alloc_nilfs(sb->s_bdev);
if (!nilfs) {
err = -ENOMEM;
goto failed_sbi;
}
sbi->s_nilfs = nilfs;
err = init_nilfs(nilfs, sbi, (char *)data);
if (err)
goto failed_nilfs;
spin_lock_init(&sbi->s_inode_lock);
INIT_LIST_HEAD(&sbi->s_dirty_files);
/*
* Following initialization is overlapped because
* nilfs_sb_info structure has been cleared at the beginning.
* But we reserve them to keep our interest and make ready
* for the future change.
*/
get_random_bytes(&sbi->s_next_generation,
sizeof(sbi->s_next_generation));
spin_lock_init(&sbi->s_next_gen_lock);
sb->s_op = &nilfs_sops;
sb->s_export_op = &nilfs_export_ops;
sb->s_root = NULL;
sb->s_time_gran = 1;
bdi = sb->s_bdev->bd_inode->i_mapping->backing_dev_info;
sb->s_bdi = bdi ? : &default_backing_dev_info;
err = load_nilfs(nilfs, sbi);
if (err)
goto failed_nilfs;
cno = nilfs_last_cno(nilfs);
err = nilfs_attach_checkpoint(sbi, cno, true, &fsroot);
if (err) {
printk(KERN_ERR "NILFS: error loading last checkpoint "
"(checkpoint number=%llu).\n", (unsigned long long)cno);
goto failed_unload;
}
if (!(sb->s_flags & MS_RDONLY)) {
err = nilfs_attach_segment_constructor(sbi, fsroot);
if (err)
goto failed_checkpoint;
}
err = nilfs_get_root_dentry(sb, fsroot, &sb->s_root);
if (err)
goto failed_segctor;
nilfs_put_root(fsroot);
if (!(sb->s_flags & MS_RDONLY)) {
down_write(&nilfs->ns_sem);
nilfs_setup_super(sbi, true);
up_write(&nilfs->ns_sem);
}
return 0;
failed_segctor:
nilfs_detach_segment_constructor(sbi);
failed_checkpoint:
nilfs_put_root(fsroot);
failed_unload:
iput(nilfs->ns_sufile);
iput(nilfs->ns_cpfile);
iput(nilfs->ns_dat);
failed_nilfs:
destroy_nilfs(nilfs);
failed_sbi:
sb->s_fs_info = NULL;
kfree(sbi);
return err;
}
static int nilfs_remount(struct super_block *sb, int *flags, char *data)
{
struct nilfs_sb_info *sbi = NILFS_SB(sb);
struct the_nilfs *nilfs = sbi->s_nilfs;
unsigned long old_sb_flags;
unsigned long old_mount_opt;
int err;
old_sb_flags = sb->s_flags;
old_mount_opt = sbi->s_mount_opt;
if (!parse_options(data, sb, 1)) {
err = -EINVAL;
goto restore_opts;
}
sb->s_flags = (sb->s_flags & ~MS_POSIXACL);
err = -EINVAL;
if (!nilfs_valid_fs(nilfs)) {
printk(KERN_WARNING "NILFS (device %s): couldn't "
"remount because the filesystem is in an "
"incomplete recovery state.\n", sb->s_id);
goto restore_opts;
}
if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
goto out;
if (*flags & MS_RDONLY) {
/* Shutting down the segment constructor */
nilfs_detach_segment_constructor(sbi);
sb->s_flags |= MS_RDONLY;
/*
* Remounting a valid RW partition RDONLY, so set
* the RDONLY flag and then mark the partition as valid again.
*/
down_write(&nilfs->ns_sem);
nilfs_cleanup_super(sbi);
up_write(&nilfs->ns_sem);
} else {
__u64 features;
struct nilfs_root *root;
/*
* Mounting a RDONLY partition read-write, so reread and
* store the current valid flag. (It may have been changed
* by fsck since we originally mounted the partition.)
*/
down_read(&nilfs->ns_sem);
features = le64_to_cpu(nilfs->ns_sbp[0]->s_feature_compat_ro) &
~NILFS_FEATURE_COMPAT_RO_SUPP;
up_read(&nilfs->ns_sem);
if (features) {
printk(KERN_WARNING "NILFS (device %s): couldn't "
"remount RDWR because of unsupported optional "
"features (%llx)\n",
sb->s_id, (unsigned long long)features);
err = -EROFS;
goto restore_opts;
}
sb->s_flags &= ~MS_RDONLY;
root = NILFS_I(sb->s_root->d_inode)->i_root;
err = nilfs_attach_segment_constructor(sbi, root);
if (err)
goto restore_opts;
down_write(&nilfs->ns_sem);
nilfs_setup_super(sbi, true);
up_write(&nilfs->ns_sem);
}
out:
return 0;
restore_opts:
sb->s_flags = old_sb_flags;
sbi->s_mount_opt = old_mount_opt;
return err;
}
/**
* nilfs_fill_super() - initialize a super block instance
* @sb: super_block
* @data: mount options
* @silent: silent mode flag
* @nilfs: the_nilfs struct
*
* This function is called exclusively by nilfs->ns_mount_mutex.
* So, the recovery process is protected from other simultaneous mounts.
*/
static int
nilfs_fill_super(struct super_block *sb, void *data, int silent,
struct the_nilfs *nilfs)
{
struct nilfs_sb_info *sbi;
struct inode *root;
__u64 cno;
int err;
sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
if (!sbi)
return -ENOMEM;
sb->s_fs_info = sbi;
get_nilfs(nilfs);
sbi->s_nilfs = nilfs;
sbi->s_super = sb;
atomic_set(&sbi->s_count, 1);
err = init_nilfs(nilfs, sbi, (char *)data);
if (err)
goto failed_sbi;
spin_lock_init(&sbi->s_inode_lock);
INIT_LIST_HEAD(&sbi->s_dirty_files);
INIT_LIST_HEAD(&sbi->s_list);
/*
* Following initialization is overlapped because
* nilfs_sb_info structure has been cleared at the beginning.
* But we reserve them to keep our interest and make ready
* for the future change.
*/
get_random_bytes(&sbi->s_next_generation,
sizeof(sbi->s_next_generation));
spin_lock_init(&sbi->s_next_gen_lock);
sb->s_op = &nilfs_sops;
sb->s_export_op = &nilfs_export_ops;
sb->s_root = NULL;
sb->s_time_gran = 1;
sb->s_bdi = nilfs->ns_bdi;
err = load_nilfs(nilfs, sbi);
if (err)
goto failed_sbi;
cno = nilfs_last_cno(nilfs);
if (sb->s_flags & MS_RDONLY) {
if (nilfs_test_opt(sbi, SNAPSHOT)) {
down_read(&nilfs->ns_segctor_sem);
err = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile,
sbi->s_snapshot_cno);
up_read(&nilfs->ns_segctor_sem);
if (err < 0) {
if (err == -ENOENT)
err = -EINVAL;
goto failed_sbi;
}
if (!err) {
printk(KERN_ERR
"NILFS: The specified checkpoint is "
"not a snapshot "
"(checkpoint number=%llu).\n",
(unsigned long long)sbi->s_snapshot_cno);
err = -EINVAL;
goto failed_sbi;
}
cno = sbi->s_snapshot_cno;
}
}
err = nilfs_attach_checkpoint(sbi, cno);
if (err) {
printk(KERN_ERR "NILFS: error loading a checkpoint"
" (checkpoint number=%llu).\n", (unsigned long long)cno);
goto failed_sbi;
}
if (!(sb->s_flags & MS_RDONLY)) {
err = nilfs_attach_segment_constructor(sbi);
if (err)
goto failed_checkpoint;
}
root = nilfs_iget(sb, NILFS_ROOT_INO);
if (IS_ERR(root)) {
printk(KERN_ERR "NILFS: get root inode failed\n");
err = PTR_ERR(root);
goto failed_segctor;
}
if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
iput(root);
printk(KERN_ERR "NILFS: corrupt root inode.\n");
err = -EINVAL;
goto failed_segctor;
}
sb->s_root = d_alloc_root(root);
if (!sb->s_root) {
iput(root);
printk(KERN_ERR "NILFS: get root dentry failed\n");
err = -ENOMEM;
goto failed_segctor;
}
if (!(sb->s_flags & MS_RDONLY)) {
down_write(&nilfs->ns_sem);
nilfs_setup_super(sbi);
up_write(&nilfs->ns_sem);
}
down_write(&nilfs->ns_super_sem);
if (!nilfs_test_opt(sbi, SNAPSHOT))
nilfs->ns_current = sbi;
up_write(&nilfs->ns_super_sem);
return 0;
failed_segctor:
nilfs_detach_segment_constructor(sbi);
failed_checkpoint:
nilfs_detach_checkpoint(sbi);
failed_sbi:
put_nilfs(nilfs);
sb->s_fs_info = NULL;
nilfs_put_sbinfo(sbi);
return err;
}
static int nilfs_remount(struct super_block *sb, int *flags, char *data)
{
struct nilfs_sb_info *sbi = NILFS_SB(sb);
struct nilfs_super_block *sbp;
struct the_nilfs *nilfs = sbi->s_nilfs;
unsigned long old_sb_flags;
struct nilfs_mount_options old_opts;
int was_snapshot, err;
down_write(&nilfs->ns_super_sem);
old_sb_flags = sb->s_flags;
old_opts.mount_opt = sbi->s_mount_opt;
old_opts.snapshot_cno = sbi->s_snapshot_cno;
was_snapshot = nilfs_test_opt(sbi, SNAPSHOT);
if (!parse_options(data, sb)) {
err = -EINVAL;
goto restore_opts;
}
sb->s_flags = (sb->s_flags & ~MS_POSIXACL);
err = -EINVAL;
if (was_snapshot) {
if (!(*flags & MS_RDONLY)) {
printk(KERN_ERR "NILFS (device %s): cannot remount "
"snapshot read/write.\n",
sb->s_id);
goto restore_opts;
} else if (sbi->s_snapshot_cno != old_opts.snapshot_cno) {
printk(KERN_ERR "NILFS (device %s): cannot "
"remount to a different snapshot.\n",
sb->s_id);
goto restore_opts;
}
} else {
if (nilfs_test_opt(sbi, SNAPSHOT)) {
printk(KERN_ERR "NILFS (device %s): cannot change "
"a regular mount to a snapshot.\n",
sb->s_id);
goto restore_opts;
}
}
if (!nilfs_valid_fs(nilfs)) {
printk(KERN_WARNING "NILFS (device %s): couldn't "
"remount because the filesystem is in an "
"incomplete recovery state.\n", sb->s_id);
goto restore_opts;
}
if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
goto out;
if (*flags & MS_RDONLY) {
/* Shutting down the segment constructor */
nilfs_detach_segment_constructor(sbi);
sb->s_flags |= MS_RDONLY;
/*
* Remounting a valid RW partition RDONLY, so set
* the RDONLY flag and then mark the partition as valid again.
*/
down_write(&nilfs->ns_sem);
sbp = nilfs->ns_sbp[0];
if (!(sbp->s_state & le16_to_cpu(NILFS_VALID_FS)) &&
(nilfs->ns_mount_state & NILFS_VALID_FS))
sbp->s_state = cpu_to_le16(nilfs->ns_mount_state);
sbp->s_mtime = cpu_to_le64(get_seconds());
nilfs_commit_super(sbi, 1);
up_write(&nilfs->ns_sem);
} else {
/*
* Mounting a RDONLY partition read-write, so reread and
* store the current valid flag. (It may have been changed
* by fsck since we originally mounted the partition.)
*/
sb->s_flags &= ~MS_RDONLY;
err = nilfs_attach_segment_constructor(sbi);
if (err)
goto restore_opts;
down_write(&nilfs->ns_sem);
nilfs_setup_super(sbi);
up_write(&nilfs->ns_sem);
}
out:
up_write(&nilfs->ns_super_sem);
return 0;
restore_opts:
sb->s_flags = old_sb_flags;
sbi->s_mount_opt = old_opts.mount_opt;
sbi->s_snapshot_cno = old_opts.snapshot_cno;
up_write(&nilfs->ns_super_sem);
return err;
}
static int nilfs_remount(struct super_block *sb, int *flags, char *data)
{
struct nilfs_sb_info *sbi = NILFS_SB(sb);
struct nilfs_super_block *sbp;
struct the_nilfs *nilfs = sbi->s_nilfs;
unsigned long old_sb_flags;
struct nilfs_mount_options old_opts;
int err;
old_sb_flags = sb->s_flags;
old_opts.mount_opt = sbi->s_mount_opt;
old_opts.snapshot_cno = sbi->s_snapshot_cno;
if (!parse_options(data, sb)) {
err = -EINVAL;
goto restore_opts;
}
sb->s_flags = (sb->s_flags & ~MS_POSIXACL);
if ((*flags & MS_RDONLY) &&
sbi->s_snapshot_cno != old_opts.snapshot_cno) {
printk(KERN_WARNING "NILFS (device %s): couldn't "
"remount to a different snapshot. \n",
sb->s_id);
err = -EINVAL;
goto restore_opts;
}
if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
goto out;
if (*flags & MS_RDONLY) {
/* Shutting down the segment constructor */
nilfs_detach_segment_constructor(sbi);
sb->s_flags |= MS_RDONLY;
sbi->s_snapshot_cno = nilfs_last_cno(nilfs);
/* nilfs_set_opt(sbi, SNAPSHOT); */
/*
* Remounting a valid RW partition RDONLY, so set
* the RDONLY flag and then mark the partition as valid again.
*/
down_write(&nilfs->ns_sem);
sbp = nilfs->ns_sbp[0];
if (!(sbp->s_state & le16_to_cpu(NILFS_VALID_FS)) &&
(nilfs->ns_mount_state & NILFS_VALID_FS))
sbp->s_state = cpu_to_le16(nilfs->ns_mount_state);
sbp->s_mtime = cpu_to_le64(get_seconds());
nilfs_commit_super(sbi, 1);
up_write(&nilfs->ns_sem);
} else {
/*
* Mounting a RDONLY partition read-write, so reread and
* store the current valid flag. (It may have been changed
* by fsck since we originally mounted the partition.)
*/
down(&sb->s_bdev->bd_mount_sem);
/* Check existing RW-mount */
if (test_exclusive_mount(sb->s_type, sb->s_bdev, 0)) {
printk(KERN_WARNING "NILFS (device %s): couldn't "
"remount because a RW-mount exists.\n",
sb->s_id);
err = -EBUSY;
goto rw_remount_failed;
}
if (sbi->s_snapshot_cno != nilfs_last_cno(nilfs)) {
printk(KERN_WARNING "NILFS (device %s): couldn't "
"remount because the current RO-mount is not "
"the latest one.\n",
sb->s_id);
err = -EINVAL;
goto rw_remount_failed;
}
sb->s_flags &= ~MS_RDONLY;
nilfs_clear_opt(sbi, SNAPSHOT);
sbi->s_snapshot_cno = 0;
err = nilfs_attach_segment_constructor(sbi);
if (err)
goto rw_remount_failed;
down_write(&nilfs->ns_sem);
nilfs_setup_super(sbi);
up_write(&nilfs->ns_sem);
up(&sb->s_bdev->bd_mount_sem);
}
out:
return 0;
rw_remount_failed:
up(&sb->s_bdev->bd_mount_sem);
restore_opts:
sb->s_flags = old_sb_flags;
sbi->s_mount_opt = old_opts.mount_opt;
sbi->s_snapshot_cno = old_opts.snapshot_cno;
return err;
}