scrub_stripe_get_kaddr
void *first_kaddr = scrub_stripe_get_kaddr(stripe, sector_nr);
btrfs_csum_update(&csum, scrub_stripe_get_kaddr(stripe, i),
if (scrub_stripe_get_kaddr(stripe, i) == bvec_virt(first_bvec))
void *kaddr = scrub_stripe_get_kaddr(stripe, sector_nr);