XFS_RTSUMMARY_MAGIC
.magic = { 0, cpu_to_be32(XFS_RTSUMMARY_MAGIC) },
hdr->rt_magic = cpu_to_be32(XFS_RTSUMMARY_MAGIC);
hdr->rt_magic = cpu_to_be32(XFS_RTSUMMARY_MAGIC);
if (xfs_has_rtgroups(mp) && magic32 != XFS_RTSUMMARY_MAGIC) {
case XFS_RTSUMMARY_MAGIC: