示例#1
0
long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
	struct inode *inode = file_inode(filp);
	struct super_block *sb = inode->i_sb;
	struct ext4_inode_info *ei = EXT4_I(inode);
	unsigned int flags;

	ext4_debug("cmd = %u, arg = %lu\n", cmd, arg);

	switch (cmd) {
	case EXT4_IOC_GETFLAGS:
		ext4_get_inode_flags(ei);
		flags = ei->i_flags & EXT4_FL_USER_VISIBLE;
		return put_user(flags, (int __user *) arg);
	case EXT4_IOC_SETFLAGS: {
		handle_t *handle = NULL;
		int err, migrate = 0;
		struct ext4_iloc iloc;
		unsigned int oldflags, mask, i;
		unsigned int jflag;

		if (!inode_owner_or_capable(inode))
			return -EACCES;

		if (get_user(flags, (int __user *) arg))
			return -EFAULT;

		err = mnt_want_write_file(filp);
		if (err)
			return err;

		flags = ext4_mask_flags(inode->i_mode, flags);

		err = -EPERM;
		mutex_lock(&inode->i_mutex);
		/* Is it quota file? Do not allow user to mess with it */
		if (IS_NOQUOTA(inode))
			goto flags_out;

		oldflags = ei->i_flags;

		/* The JOURNAL_DATA flag is modifiable only by root */
		jflag = flags & EXT4_JOURNAL_DATA_FL;

		/*
		 * The IMMUTABLE and APPEND_ONLY flags can only be changed by
		 * the relevant capability.
		 *
		 * This test looks nicer. Thanks to Pauline Middelink
		 */
		if ((flags ^ oldflags) & (EXT4_APPEND_FL | EXT4_IMMUTABLE_FL)) {
			if (!capable(CAP_LINUX_IMMUTABLE))
				goto flags_out;
		}

		/*
		 * The JOURNAL_DATA flag can only be changed by
		 * the relevant capability.
		 */
		if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL)) {
			if (!capable(CAP_SYS_RESOURCE))
				goto flags_out;
		}
		if ((flags ^ oldflags) & EXT4_EXTENTS_FL)
			migrate = 1;

		if (flags & EXT4_EOFBLOCKS_FL) {
			/* we don't support adding EOFBLOCKS flag */
			if (!(oldflags & EXT4_EOFBLOCKS_FL)) {
				err = -EOPNOTSUPP;
				goto flags_out;
			}
		} else if (oldflags & EXT4_EOFBLOCKS_FL)
			ext4_truncate(inode);

		handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
		if (IS_ERR(handle)) {
			err = PTR_ERR(handle);
			goto flags_out;
		}
		if (IS_SYNC(inode))
			ext4_handle_sync(handle);
		err = ext4_reserve_inode_write(handle, inode, &iloc);
		if (err)
			goto flags_err;

		for (i = 0, mask = 1; i < 32; i++, mask <<= 1) {
			if (!(mask & EXT4_FL_USER_MODIFIABLE))
				continue;
			if (mask & flags)
				ext4_set_inode_flag(inode, i);
			else
				ext4_clear_inode_flag(inode, i);
		}

		ext4_set_inode_flags(inode);
		inode->i_ctime = ext4_current_time(inode);

		err = ext4_mark_iloc_dirty(handle, inode, &iloc);
flags_err:
		ext4_journal_stop(handle);
		if (err)
			goto flags_out;

		if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL))
			err = ext4_change_inode_journal_flag(inode, jflag);
		if (err)
			goto flags_out;
		if (migrate) {
			if (flags & EXT4_EXTENTS_FL)
				err = ext4_ext_migrate(inode);
			else
				err = ext4_ind_migrate(inode);
		}

flags_out:
		mutex_unlock(&inode->i_mutex);
		mnt_drop_write_file(filp);
		return err;
	}
	case EXT4_IOC_GETVERSION:
	case EXT4_IOC_GETVERSION_OLD:
		return put_user(inode->i_generation, (int __user *) arg);
	case EXT4_IOC_SETVERSION:
	case EXT4_IOC_SETVERSION_OLD: {
		handle_t *handle;
		struct ext4_iloc iloc;
		__u32 generation;
		int err;

		if (!inode_owner_or_capable(inode))
			return -EPERM;

		if (ext4_has_metadata_csum(inode->i_sb)) {
			ext4_warning(sb, "Setting inode version is not "
				     "supported with metadata_csum enabled.");
			return -ENOTTY;
		}

		err = mnt_want_write_file(filp);
		if (err)
			return err;
		if (get_user(generation, (int __user *) arg)) {
			err = -EFAULT;
			goto setversion_out;
		}

		mutex_lock(&inode->i_mutex);
		handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
		if (IS_ERR(handle)) {
			err = PTR_ERR(handle);
			goto unlock_out;
		}
		err = ext4_reserve_inode_write(handle, inode, &iloc);
		if (err == 0) {
			inode->i_ctime = ext4_current_time(inode);
			inode->i_generation = generation;
			err = ext4_mark_iloc_dirty(handle, inode, &iloc);
		}
		ext4_journal_stop(handle);

unlock_out:
		mutex_unlock(&inode->i_mutex);
setversion_out:
		mnt_drop_write_file(filp);
		return err;
	}
	case EXT4_IOC_GROUP_EXTEND: {
		ext4_fsblk_t n_blocks_count;
		int err, err2=0;

		err = ext4_resize_begin(sb);
		if (err)
			return err;

		if (get_user(n_blocks_count, (__u32 __user *)arg)) {
			err = -EFAULT;
			goto group_extend_out;
		}

		if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
			       EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
			ext4_msg(sb, KERN_ERR,
				 "Online resizing not supported with bigalloc");
			err = -EOPNOTSUPP;
			goto group_extend_out;
		}

		err = mnt_want_write_file(filp);
		if (err)
			goto group_extend_out;

		err = ext4_group_extend(sb, EXT4_SB(sb)->s_es, n_blocks_count);
		if (EXT4_SB(sb)->s_journal) {
			jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
			err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
			jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
		}
		if (err == 0)
			err = err2;
		mnt_drop_write_file(filp);
group_extend_out:
		ext4_resize_end(sb);
		return err;
	}

	case EXT4_IOC_MOVE_EXT: {
		struct move_extent me;
		struct fd donor;
		int err;

		if (!(filp->f_mode & FMODE_READ) ||
		    !(filp->f_mode & FMODE_WRITE))
			return -EBADF;

		if (copy_from_user(&me,
			(struct move_extent __user *)arg, sizeof(me)))
			return -EFAULT;
		me.moved_len = 0;

		donor = fdget(me.donor_fd);
		if (!donor.file)
			return -EBADF;

		if (!(donor.file->f_mode & FMODE_WRITE)) {
			err = -EBADF;
			goto mext_out;
		}

		if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
			       EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
			ext4_msg(sb, KERN_ERR,
				 "Online defrag not supported with bigalloc");
			err = -EOPNOTSUPP;
			goto mext_out;
		}

		err = mnt_want_write_file(filp);
		if (err)
			goto mext_out;

		err = ext4_move_extents(filp, donor.file, me.orig_start,
					me.donor_start, me.len, &me.moved_len);
		mnt_drop_write_file(filp);

		if (copy_to_user((struct move_extent __user *)arg,
				 &me, sizeof(me)))
			err = -EFAULT;
mext_out:
		fdput(donor);
		return err;
	}

	case EXT4_IOC_GROUP_ADD: {
		struct ext4_new_group_data input;
		int err, err2=0;

		err = ext4_resize_begin(sb);
		if (err)
			return err;

		if (copy_from_user(&input, (struct ext4_new_group_input __user *)arg,
				sizeof(input))) {
			err = -EFAULT;
			goto group_add_out;
		}

		if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
			       EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
			ext4_msg(sb, KERN_ERR,
				 "Online resizing not supported with bigalloc");
			err = -EOPNOTSUPP;
			goto group_add_out;
		}

		err = mnt_want_write_file(filp);
		if (err)
			goto group_add_out;

		err = ext4_group_add(sb, &input);
		if (EXT4_SB(sb)->s_journal) {
			jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
			err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
			jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
		}
		if (err == 0)
			err = err2;
		mnt_drop_write_file(filp);
		if (!err && ext4_has_group_desc_csum(sb) &&
		    test_opt(sb, INIT_INODE_TABLE))
			err = ext4_register_li_request(sb, input.group);
group_add_out:
		ext4_resize_end(sb);
		return err;
	}

	case EXT4_IOC_MIGRATE:
	{
		int err;
		if (!inode_owner_or_capable(inode))
			return -EACCES;

		err = mnt_want_write_file(filp);
		if (err)
			return err;
		/*
		 * inode_mutex prevent write and truncate on the file.
		 * Read still goes through. We take i_data_sem in
		 * ext4_ext_swap_inode_data before we switch the
		 * inode format to prevent read.
		 */
		mutex_lock(&(inode->i_mutex));
		err = ext4_ext_migrate(inode);
		mutex_unlock(&(inode->i_mutex));
		mnt_drop_write_file(filp);
		return err;
	}

	case EXT4_IOC_ALLOC_DA_BLKS:
	{
		int err;
		if (!inode_owner_or_capable(inode))
			return -EACCES;

		err = mnt_want_write_file(filp);
		if (err)
			return err;
		err = ext4_alloc_da_blocks(inode);
		mnt_drop_write_file(filp);
		return err;
	}

	case EXT4_IOC_SWAP_BOOT:
	{
		int err;
		if (!(filp->f_mode & FMODE_WRITE))
			return -EBADF;
		err = mnt_want_write_file(filp);
		if (err)
			return err;
		err = swap_inode_boot_loader(sb, inode);
		mnt_drop_write_file(filp);
		return err;
	}

	case EXT4_IOC_RESIZE_FS: {
		ext4_fsblk_t n_blocks_count;
		int err = 0, err2 = 0;
		ext4_group_t o_group = EXT4_SB(sb)->s_groups_count;

		if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
			       EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
			ext4_msg(sb, KERN_ERR,
				 "Online resizing not (yet) supported with bigalloc");
			return -EOPNOTSUPP;
		}

		if (copy_from_user(&n_blocks_count, (__u64 __user *)arg,
				   sizeof(__u64))) {
			return -EFAULT;
		}

		err = ext4_resize_begin(sb);
		if (err)
			return err;

		err = mnt_want_write_file(filp);
		if (err)
			goto resizefs_out;

		err = ext4_resize_fs(sb, n_blocks_count);
		if (EXT4_SB(sb)->s_journal) {
			jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
			err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
			jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
		}
		if (err == 0)
			err = err2;
		mnt_drop_write_file(filp);
		if (!err && (o_group > EXT4_SB(sb)->s_groups_count) &&
		    ext4_has_group_desc_csum(sb) &&
		    test_opt(sb, INIT_INODE_TABLE))
			err = ext4_register_li_request(sb, o_group);

resizefs_out:
		ext4_resize_end(sb);
		return err;
	}

	case FITRIM:
	{
		struct request_queue *q = bdev_get_queue(sb->s_bdev);
		struct fstrim_range range;
		int ret = 0;

		if (!capable(CAP_SYS_ADMIN))
			return -EPERM;

		if (!blk_queue_discard(q))
			return -EOPNOTSUPP;

		if (copy_from_user(&range, (struct fstrim_range __user *)arg,
		    sizeof(range)))
			return -EFAULT;

		range.minlen = max((unsigned int)range.minlen,
				   q->limits.discard_granularity);
		ret = ext4_trim_fs(sb, &range);
		if (ret < 0)
			return ret;

		if (copy_to_user((struct fstrim_range __user *)arg, &range,
		    sizeof(range)))
			return -EFAULT;

		return 0;
	}
	case EXT4_IOC_PRECACHE_EXTENTS:
		return ext4_ext_precache(inode);
	case EXT4_IOC_SET_ENCRYPTION_POLICY: {
#ifdef CONFIG_EXT4_FS_ENCRYPTION
		struct ext4_encryption_policy policy;
		int err = 0;

		if (copy_from_user(&policy,
				   (struct ext4_encryption_policy __user *)arg,
				   sizeof(policy))) {
			err = -EFAULT;
			goto encryption_policy_out;
		}

		err = ext4_process_policy(&policy, inode);
encryption_policy_out:
		return err;
#else
		return -EOPNOTSUPP;
#endif
	}
	case EXT4_IOC_GET_ENCRYPTION_PWSALT: {
		int err, err2;
		struct ext4_sb_info *sbi = EXT4_SB(sb);
		handle_t *handle;

		if (!ext4_sb_has_crypto(sb))
			return -EOPNOTSUPP;
		if (uuid_is_zero(sbi->s_es->s_encrypt_pw_salt)) {
			err = mnt_want_write_file(filp);
			if (err)
				return err;
			handle = ext4_journal_start_sb(sb, EXT4_HT_MISC, 1);
			if (IS_ERR(handle)) {
				err = PTR_ERR(handle);
				goto pwsalt_err_exit;
			}
			err = ext4_journal_get_write_access(handle, sbi->s_sbh);
			if (err)
				goto pwsalt_err_journal;
			generate_random_uuid(sbi->s_es->s_encrypt_pw_salt);
			err = ext4_handle_dirty_metadata(handle, NULL,
							 sbi->s_sbh);
		pwsalt_err_journal:
			err2 = ext4_journal_stop(handle);
			if (err2 && !err)
				err = err2;
		pwsalt_err_exit:
			mnt_drop_write_file(filp);
			if (err)
				return err;
		}
		if (copy_to_user((void *) arg, sbi->s_es->s_encrypt_pw_salt,
				 16))
			return -EFAULT;
		return 0;
	}
	case EXT4_IOC_GET_ENCRYPTION_POLICY: {
#ifdef CONFIG_EXT4_FS_ENCRYPTION
		struct ext4_encryption_policy policy;
		int err = 0;

		if (!ext4_encrypted_inode(inode))
			return -ENOENT;
		err = ext4_get_policy(inode, &policy);
		if (err)
			return err;
		if (copy_to_user((void *)arg, &policy, sizeof(policy)))
			return -EFAULT;
		return 0;
#else
		return -EOPNOTSUPP;
#endif
	}
	default:
		return -ENOTTY;
	}
}
示例#2
0
文件: ioctl.c 项目: andy-shev/linux
long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
	struct inode *inode = file_inode(filp);
	struct super_block *sb = inode->i_sb;
	struct ext4_inode_info *ei = EXT4_I(inode);
	unsigned int flags;

	ext4_debug("cmd = %u, arg = %lu\n", cmd, arg);

	switch (cmd) {
	case EXT4_IOC_GETFLAGS:
		ext4_get_inode_flags(ei);
		flags = ei->i_flags & EXT4_FL_USER_VISIBLE;
		return put_user(flags, (int __user *) arg);
	case EXT4_IOC_SETFLAGS: {
		int err;

		if (!inode_owner_or_capable(inode))
			return -EACCES;

		if (get_user(flags, (int __user *) arg))
			return -EFAULT;

		err = mnt_want_write_file(filp);
		if (err)
			return err;

		flags = ext4_mask_flags(inode->i_mode, flags);

		inode_lock(inode);
		err = ext4_ioctl_setflags(inode, flags);
		inode_unlock(inode);
		mnt_drop_write_file(filp);
		return err;
	}
	case EXT4_IOC_GETVERSION:
	case EXT4_IOC_GETVERSION_OLD:
		return put_user(inode->i_generation, (int __user *) arg);
	case EXT4_IOC_SETVERSION:
	case EXT4_IOC_SETVERSION_OLD: {
		handle_t *handle;
		struct ext4_iloc iloc;
		__u32 generation;
		int err;

		if (!inode_owner_or_capable(inode))
			return -EPERM;

		if (ext4_has_metadata_csum(inode->i_sb)) {
			ext4_warning(sb, "Setting inode version is not "
				     "supported with metadata_csum enabled.");
			return -ENOTTY;
		}

		err = mnt_want_write_file(filp);
		if (err)
			return err;
		if (get_user(generation, (int __user *) arg)) {
			err = -EFAULT;
			goto setversion_out;
		}

		inode_lock(inode);
		handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
		if (IS_ERR(handle)) {
			err = PTR_ERR(handle);
			goto unlock_out;
		}
		err = ext4_reserve_inode_write(handle, inode, &iloc);
		if (err == 0) {
			inode->i_ctime = ext4_current_time(inode);
			inode->i_generation = generation;
			err = ext4_mark_iloc_dirty(handle, inode, &iloc);
		}
		ext4_journal_stop(handle);

unlock_out:
		inode_unlock(inode);
setversion_out:
		mnt_drop_write_file(filp);
		return err;
	}
	case EXT4_IOC_GROUP_EXTEND: {
		ext4_fsblk_t n_blocks_count;
		int err, err2=0;

		err = ext4_resize_begin(sb);
		if (err)
			return err;

		if (get_user(n_blocks_count, (__u32 __user *)arg)) {
			err = -EFAULT;
			goto group_extend_out;
		}

		if (ext4_has_feature_bigalloc(sb)) {
			ext4_msg(sb, KERN_ERR,
				 "Online resizing not supported with bigalloc");
			err = -EOPNOTSUPP;
			goto group_extend_out;
		}

		err = mnt_want_write_file(filp);
		if (err)
			goto group_extend_out;

		err = ext4_group_extend(sb, EXT4_SB(sb)->s_es, n_blocks_count);
		if (EXT4_SB(sb)->s_journal) {
			jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
			err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
			jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
		}
		if (err == 0)
			err = err2;
		mnt_drop_write_file(filp);
group_extend_out:
		ext4_resize_end(sb);
		return err;
	}

	case EXT4_IOC_MOVE_EXT: {
		struct move_extent me;
		struct fd donor;
		int err;

		if (!(filp->f_mode & FMODE_READ) ||
		    !(filp->f_mode & FMODE_WRITE))
			return -EBADF;

		if (copy_from_user(&me,
			(struct move_extent __user *)arg, sizeof(me)))
			return -EFAULT;
		me.moved_len = 0;

		donor = fdget(me.donor_fd);
		if (!donor.file)
			return -EBADF;

		if (!(donor.file->f_mode & FMODE_WRITE)) {
			err = -EBADF;
			goto mext_out;
		}

		if (ext4_has_feature_bigalloc(sb)) {
			ext4_msg(sb, KERN_ERR,
				 "Online defrag not supported with bigalloc");
			err = -EOPNOTSUPP;
			goto mext_out;
		}

		err = mnt_want_write_file(filp);
		if (err)
			goto mext_out;

		err = ext4_move_extents(filp, donor.file, me.orig_start,
					me.donor_start, me.len, &me.moved_len);
		mnt_drop_write_file(filp);

		if (copy_to_user((struct move_extent __user *)arg,
				 &me, sizeof(me)))
			err = -EFAULT;
mext_out:
		fdput(donor);
		return err;
	}

	case EXT4_IOC_GROUP_ADD: {
		struct ext4_new_group_data input;
		int err, err2=0;

		err = ext4_resize_begin(sb);
		if (err)
			return err;

		if (copy_from_user(&input, (struct ext4_new_group_input __user *)arg,
				sizeof(input))) {
			err = -EFAULT;
			goto group_add_out;
		}

		if (ext4_has_feature_bigalloc(sb)) {
			ext4_msg(sb, KERN_ERR,
				 "Online resizing not supported with bigalloc");
			err = -EOPNOTSUPP;
			goto group_add_out;
		}

		err = mnt_want_write_file(filp);
		if (err)
			goto group_add_out;

		err = ext4_group_add(sb, &input);
		if (EXT4_SB(sb)->s_journal) {
			jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
			err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
			jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
		}
		if (err == 0)
			err = err2;
		mnt_drop_write_file(filp);
		if (!err && ext4_has_group_desc_csum(sb) &&
		    test_opt(sb, INIT_INODE_TABLE))
			err = ext4_register_li_request(sb, input.group);
group_add_out:
		ext4_resize_end(sb);
		return err;
	}

	case EXT4_IOC_MIGRATE:
	{
		int err;
		if (!inode_owner_or_capable(inode))
			return -EACCES;

		err = mnt_want_write_file(filp);
		if (err)
			return err;
		/*
		 * inode_mutex prevent write and truncate on the file.
		 * Read still goes through. We take i_data_sem in
		 * ext4_ext_swap_inode_data before we switch the
		 * inode format to prevent read.
		 */
		inode_lock((inode));
		err = ext4_ext_migrate(inode);
		inode_unlock((inode));
		mnt_drop_write_file(filp);
		return err;
	}

	case EXT4_IOC_ALLOC_DA_BLKS:
	{
		int err;
		if (!inode_owner_or_capable(inode))
			return -EACCES;

		err = mnt_want_write_file(filp);
		if (err)
			return err;
		err = ext4_alloc_da_blocks(inode);
		mnt_drop_write_file(filp);
		return err;
	}

	case EXT4_IOC_SWAP_BOOT:
	{
		int err;
		if (!(filp->f_mode & FMODE_WRITE))
			return -EBADF;
		err = mnt_want_write_file(filp);
		if (err)
			return err;
		err = swap_inode_boot_loader(sb, inode);
		mnt_drop_write_file(filp);
		return err;
	}

	case EXT4_IOC_RESIZE_FS: {
		ext4_fsblk_t n_blocks_count;
		int err = 0, err2 = 0;
		ext4_group_t o_group = EXT4_SB(sb)->s_groups_count;

		if (ext4_has_feature_bigalloc(sb)) {
			ext4_msg(sb, KERN_ERR,
				 "Online resizing not (yet) supported with bigalloc");
			return -EOPNOTSUPP;
		}

		if (copy_from_user(&n_blocks_count, (__u64 __user *)arg,
				   sizeof(__u64))) {
			return -EFAULT;
		}

		err = ext4_resize_begin(sb);
		if (err)
			return err;

		err = mnt_want_write_file(filp);
		if (err)
			goto resizefs_out;

		err = ext4_resize_fs(sb, n_blocks_count);
		if (EXT4_SB(sb)->s_journal) {
			jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
			err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
			jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
		}
		if (err == 0)
			err = err2;
		mnt_drop_write_file(filp);
		if (!err && (o_group > EXT4_SB(sb)->s_groups_count) &&
		    ext4_has_group_desc_csum(sb) &&
		    test_opt(sb, INIT_INODE_TABLE))
			err = ext4_register_li_request(sb, o_group);

resizefs_out:
		ext4_resize_end(sb);
		return err;
	}

	case FITRIM:
	{
		struct request_queue *q = bdev_get_queue(sb->s_bdev);
		struct fstrim_range range;
		int ret = 0;

		if (!capable(CAP_SYS_ADMIN))
			return -EPERM;

		if (!blk_queue_discard(q))
			return -EOPNOTSUPP;

		if (copy_from_user(&range, (struct fstrim_range __user *)arg,
		    sizeof(range)))
			return -EFAULT;

		range.minlen = max((unsigned int)range.minlen,
				   q->limits.discard_granularity);
		ret = ext4_trim_fs(sb, &range);
		if (ret < 0)
			return ret;

		if (copy_to_user((struct fstrim_range __user *)arg, &range,
		    sizeof(range)))
			return -EFAULT;

		return 0;
	}
	case EXT4_IOC_PRECACHE_EXTENTS:
		return ext4_ext_precache(inode);
	case EXT4_IOC_SET_ENCRYPTION_POLICY: {
#ifdef CONFIG_EXT4_FS_ENCRYPTION
		struct ext4_encryption_policy policy;
		int err = 0;

		if (copy_from_user(&policy,
				   (struct ext4_encryption_policy __user *)arg,
				   sizeof(policy))) {
			err = -EFAULT;
			goto encryption_policy_out;
		}

		err = ext4_process_policy(&policy, inode);
encryption_policy_out:
		return err;
#else
		return -EOPNOTSUPP;
#endif
	}
	case EXT4_IOC_GET_ENCRYPTION_PWSALT: {
		int err, err2;
		struct ext4_sb_info *sbi = EXT4_SB(sb);
		handle_t *handle;

		if (!ext4_sb_has_crypto(sb))
			return -EOPNOTSUPP;
		if (uuid_is_zero(sbi->s_es->s_encrypt_pw_salt)) {
			err = mnt_want_write_file(filp);
			if (err)
				return err;
			handle = ext4_journal_start_sb(sb, EXT4_HT_MISC, 1);
			if (IS_ERR(handle)) {
				err = PTR_ERR(handle);
				goto pwsalt_err_exit;
			}
			err = ext4_journal_get_write_access(handle, sbi->s_sbh);
			if (err)
				goto pwsalt_err_journal;
			generate_random_uuid(sbi->s_es->s_encrypt_pw_salt);
			err = ext4_handle_dirty_metadata(handle, NULL,
							 sbi->s_sbh);
		pwsalt_err_journal:
			err2 = ext4_journal_stop(handle);
			if (err2 && !err)
				err = err2;
		pwsalt_err_exit:
			mnt_drop_write_file(filp);
			if (err)
				return err;
		}
		if (copy_to_user((void __user *) arg,
				 sbi->s_es->s_encrypt_pw_salt, 16))
			return -EFAULT;
		return 0;
	}
	case EXT4_IOC_GET_ENCRYPTION_POLICY: {
#ifdef CONFIG_EXT4_FS_ENCRYPTION
		struct ext4_encryption_policy policy;
		int err = 0;

		if (!ext4_encrypted_inode(inode))
			return -ENOENT;
		err = ext4_get_policy(inode, &policy);
		if (err)
			return err;
		if (copy_to_user((void __user *)arg, &policy, sizeof(policy)))
			return -EFAULT;
		return 0;
#else
		return -EOPNOTSUPP;
#endif
	}
	case EXT4_IOC_FSGETXATTR:
	{
		struct fsxattr fa;

		memset(&fa, 0, sizeof(struct fsxattr));
		ext4_get_inode_flags(ei);
		fa.fsx_xflags = ext4_iflags_to_xflags(ei->i_flags & EXT4_FL_USER_VISIBLE);

		if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
				EXT4_FEATURE_RO_COMPAT_PROJECT)) {
			fa.fsx_projid = (__u32)from_kprojid(&init_user_ns,
				EXT4_I(inode)->i_projid);
		}

		if (copy_to_user((struct fsxattr __user *)arg,
				 &fa, sizeof(fa)))
			return -EFAULT;
		return 0;
	}
	case EXT4_IOC_FSSETXATTR:
	{
		struct fsxattr fa;
		int err;

		if (copy_from_user(&fa, (struct fsxattr __user *)arg,
				   sizeof(fa)))
			return -EFAULT;

		/* Make sure caller has proper permission */
		if (!inode_owner_or_capable(inode))
			return -EACCES;

		err = mnt_want_write_file(filp);
		if (err)
			return err;

		flags = ext4_xflags_to_iflags(fa.fsx_xflags);
		flags = ext4_mask_flags(inode->i_mode, flags);

		inode_lock(inode);
		flags = (ei->i_flags & ~EXT4_FL_XFLAG_VISIBLE) |
			 (flags & EXT4_FL_XFLAG_VISIBLE);
		err = ext4_ioctl_setflags(inode, flags);
		inode_unlock(inode);
		mnt_drop_write_file(filp);
		if (err)
			return err;

		err = ext4_ioctl_setproject(filp, fa.fsx_projid);
		if (err)
			return err;

		return 0;
	}
	default:
		return -ENOTTY;
	}
}