> +int
> +ufs_gop_write(struct vnode *vp, struct vm_page **pgs, int npages, int flags)
> +{
> +	struct inode *ip = VTOI(vp);
> +	int error;
> +
> +	error = genfs_gop_write(vp, pgs, npages, flags);
> +	if (error == 0) {
> +		/* file has been written, update mtime */
> +		ip->i_flag |= IN_CHANGE | IN_UPDATE;
> +	}
> +	return error;
> +}

as modifications are visible to the world at this point,
"if (error == 0)" here doesn't make much sense.

YAMAMOTO Takashi