static int fuse_file_lock(struct file *file, int cmd, struct file_lock *fl)
{
	struct inode *inode = file_inode(file);
	struct fuse_conn *fc = get_fuse_conn(inode);
	int err;

	if (cmd == F_CANCELLK) {
		err = 0;
	} else if (cmd == F_GETLK) {
		if (fc->no_lock) {
			posix_test_lock(file, fl);
			err = 0;
		} else
			err = fuse_getlk(file, fl);
	} else {
		if (fc->no_lock)
			err = posix_lock_file(file, fl, NULL);
		else
			err = fuse_setlk(file, fl, 0);
	}
	return err;
}