- /* magic number and level verification */
- level = be16_to_cpu(block->bb_level);
- sblock_ok = block->bb_magic == cpu_to_be32(XFS_IBT_MAGIC) &&
- level < mp->m_in_maxlevels;
+ /*
+ * During growfs operations, we can't verify the exact owner as the
+ * perag is not fully initialised and hence not attached to the buffer.
+ *
+ * Similarly, during log recovery we will have a perag structure
+ * attached, but the agi information will not yet have been initialised
+ * from the on disk AGI. We don't currently use any of this information,
+ * but beware of the landmine (i.e. need to check pag->pagi_init) if we
+ * ever do.
+ */
+ switch (block->bb_magic) {
+ case cpu_to_be32(XFS_IBT_CRC_MAGIC):
+ if (!xfs_sb_version_hascrc(&mp->m_sb))
+ return false;
+ if (!uuid_equal(&block->bb_u.s.bb_uuid, &mp->m_sb.sb_uuid))
+ return false;
+ if (block->bb_u.s.bb_blkno != cpu_to_be64(bp->b_bn))
+ return false;
+ if (pag &&
+ be32_to_cpu(block->bb_u.s.bb_owner) != pag->pag_agno)
+ return false;
+ /* fall through */
+ case cpu_to_be32(XFS_IBT_MAGIC):
+ break;
+ default:
+ return 0;
+ }