On Tue, Aug 26, 2025 at 03:57:34PM +0200, Christoph Hellwig wrote: > On Tue, Aug 26, 2025 at 07:47:46AM -0600, Keith Busch wrote: > > Currently, the virtual boundary is always compared to bv_offset, which > > is a page offset. If the virtual boundary is larger than a page, then we > > need something like "page_to_phys(bv.bv_page) + bv.bv_offset" every > > place we need to check against the virt boundary. > > bv_offset is only guaranteed to be a page offset if your use > bio_for_each_segment(_all) or the low-level helpers implementing > it and not bio_for_each_bvec(_all) where it can be much larger > than PAGE_SIZE. Yes, good point. So we'd have a folio offset when it's not a single page, but I don't think we want to special case large folios for every virt boundary check. It's looking like replace bvec's "page + offset" with phys addrs, yeah?!
