Function vdev_draid_get_astart

freebsd/contrib/openzfs/module/zfs/vdev_draid.c:1349–1357

* Given an offset into a dRAID return the next group width aligned offset * which can be used to start an allocation. */

 * which can be used to start an allocation.
 */
static uint64_t
vdev_draid_get_astart(vdev_t *vd, const uint64_t start)
{
	vdev_draid_config_t *vdc = vd->vdev_tsd;

	ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops);

	return (roundup(start, vdc->vdc_groupwidth << vd->vdev_ashift));
}

/*
 * Allocatable space for dRAID is (children - nspares) * sizeof(smallest child)