예제 #1
0
파일: super.c 프로젝트: ANFS/ANFS-kernel
static int nilfs_attach_snapshot(struct super_block *s, __u64 cno,
				 struct dentry **root_dentry)
{
	struct the_nilfs *nilfs = NILFS_SB(s)->s_nilfs;
	struct nilfs_root *root;
	int ret;

	down_read(&nilfs->ns_segctor_sem);
	ret = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile, cno);
	up_read(&nilfs->ns_segctor_sem);
	if (ret < 0) {
		ret = (ret == -ENOENT) ? -EINVAL : ret;
		goto out;
	} else if (!ret) {
		printk(KERN_ERR "NILFS: The specified checkpoint is "
		       "not a snapshot (checkpoint number=%llu).\n",
		       (unsigned long long)cno);
		ret = -EINVAL;
		goto out;
	}

	ret = nilfs_attach_checkpoint(NILFS_SB(s), cno, false, &root);
	if (ret) {
		printk(KERN_ERR "NILFS: error loading snapshot "
		       "(checkpoint number=%llu).\n",
	       (unsigned long long)cno);
		goto out;
	}
	ret = nilfs_get_root_dentry(s, root, root_dentry);
	nilfs_put_root(root);
 out:
	return ret;
}
예제 #2
0
파일: super.c 프로젝트: AK101111/linux
static int nilfs_attach_snapshot(struct super_block *s, __u64 cno,
				 struct dentry **root_dentry)
{
	struct the_nilfs *nilfs = s->s_fs_info;
	struct nilfs_root *root;
	int ret;

	mutex_lock(&nilfs->ns_snapshot_mount_mutex);

	down_read(&nilfs->ns_segctor_sem);
	ret = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile, cno);
	up_read(&nilfs->ns_segctor_sem);
	if (ret < 0) {
		ret = (ret == -ENOENT) ? -EINVAL : ret;
		goto out;
	} else if (!ret) {
		nilfs_msg(s, KERN_ERR,
			  "The specified checkpoint is not a snapshot (checkpoint number=%llu)",
			  (unsigned long long)cno);
		ret = -EINVAL;
		goto out;
	}

	ret = nilfs_attach_checkpoint(s, cno, false, &root);
	if (ret) {
		nilfs_msg(s, KERN_ERR,
			  "error %d while loading snapshot (checkpoint number=%llu)",
			  ret, (unsigned long long)cno);
		goto out;
	}
	ret = nilfs_get_root_dentry(s, root, root_dentry);
	nilfs_put_root(root);
 out:
	mutex_unlock(&nilfs->ns_snapshot_mount_mutex);
	return ret;
}
예제 #3
0
/**
 * 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;
}