SEGS_PER_INDIRECT_FRAME
if ((n % SEGS_PER_INDIRECT_FRAME) == 0) {
segments = kmap_atomic(pages[n/SEGS_PER_INDIRECT_FRAME]->page);
i = n % SEGS_PER_INDIRECT_FRAME;
((MAX_INDIRECT_SEGMENTS + SEGS_PER_INDIRECT_FRAME - 1)/SEGS_PER_INDIRECT_FRAME)