xfs: refactor short form btree pointer verification

Now that we have xfs_verify_agbno, use it to verify short form btree
pointers instead of open-coding them.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>

fs/xfs/libxfs/xfs_btree.c

@@ -4614,19 +4614,19 @@ xfs_btree_sblock_verify(
 {
 	struct xfs_mount	*mp = bp->b_target->bt_mount;
 	struct xfs_btree_block	*block = XFS_BUF_TO_BLOCK(bp);
+	xfs_agblock_t		agno;
 
 	/* numrecs verification */
 	if (be16_to_cpu(block->bb_numrecs) > max_recs)
 		return false;
 
 	/* sibling pointer verification */
-	if (!block->bb_u.s.bb_leftsib ||
-	    (be32_to_cpu(block->bb_u.s.bb_leftsib) >= mp->m_sb.sb_agblocks &&
-	     block->bb_u.s.bb_leftsib != cpu_to_be32(NULLAGBLOCK)))
+	agno = xfs_daddr_to_agno(mp, XFS_BUF_ADDR(bp));
+	if (block->bb_u.s.bb_leftsib != cpu_to_be32(NULLAGBLOCK) &&
+	    !xfs_verify_agbno(mp, agno, be32_to_cpu(block->bb_u.s.bb_leftsib)))
 		return false;
-	if (!block->bb_u.s.bb_rightsib ||
-	    (be32_to_cpu(block->bb_u.s.bb_rightsib) >= mp->m_sb.sb_agblocks &&
-	     block->bb_u.s.bb_rightsib != cpu_to_be32(NULLAGBLOCK)))
+	if (block->bb_u.s.bb_rightsib != cpu_to_be32(NULLAGBLOCK) &&
+	    !xfs_verify_agbno(mp, agno, be32_to_cpu(block->bb_u.s.bb_rightsib)))
 		return false;
 
 	return true;