static void cirrus_invalidate_region(CirrusVGAState * s, int off_begin,
				     int off_pitch, int bytesperline,
				     int lines)
{
    int y;
    int off_cur;
    int off_cur_end;

    for (y = 0; y < lines; y++) {
	off_cur = off_begin;
	off_cur_end = off_cur + bytesperline;
	off_cur &= TARGET_PAGE_MASK;
	while (off_cur < off_cur_end) {
	    cpu_physical_memory_set_dirty(s->vram_offset + off_cur);
	    off_cur += TARGET_PAGE_SIZE;
	}
	off_begin += off_pitch;
    }
}
Unknown