spapr_iommu: Migrate full state

The source guest could have reallocated the default TCE table and
migrate bigger/smaller table. This adds reallocation in post_load()
if the default table size is different on source and destination.

This adds @bus_offset, @page_shift to the migration stream as
a subsection so when DDW is added, migration to older machines will
still be possible. As @bus_offset and @page_shift are not used yet,
this makes no change in behavior.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
index 26c327d..f849714 100644
--- a/include/hw/ppc/spapr.h
+++ b/include/hw/ppc/spapr.h
@@ -539,6 +539,8 @@
     uint64_t bus_offset;
     uint32_t page_shift;
     uint64_t *table;
+    uint32_t mig_nb_table;
+    uint64_t *mig_table;
     bool bypass;
     bool need_vfio;
     int fd;
@@ -565,6 +567,7 @@
 void spapr_tce_table_enable(sPAPRTCETable *tcet,
                             uint32_t page_shift, uint64_t bus_offset,
                             uint32_t nb_table);
+void spapr_tce_table_disable(sPAPRTCETable *tcet);
 void spapr_tce_set_need_vfio(sPAPRTCETable *tcet, bool need_vfio);
 
 MemoryRegion *spapr_tce_get_iommu(sPAPRTCETable *tcet);