printk("Create surface");
struct doomdev_ioctl_create_surface surf_arg;
if (copy_from_user(&surf_arg, (const void __user *) arg, sizeof(struct doomdev_ioctl_create_surface))) {
    return -1;
}
printk("Create surface %d x %d", surf_arg.width, surf_arg.height);

struct surface* mem_for_surface = kmalloc(sizeof(struct surface), GFP_KERNEL);

if (IS_ERR_OR_NULL(mem_for_surface))
    return -1;

if (create_surface(dev, mem_for_surface, surf_arg.width, surf_arg.height))
{
    kfree(mem_for_surface);
    return -1;
}

struct file* surface_file = anon_inode_getfile("/doom/surface", &surface_fops, mem_for_surface, 0);

surface_file->f_mode |= FMODE_LSEEK | FMODE_PREAD | FMODE_PWRITE;

int fd = get_unused_fd_flags(O_CLOEXEC);

fd_install(fd, surface_file);

return fd;