spapr_pci: spapr_iommu: Make DMA window a subregion

Currently the default DMA window is represented by a single MemoryRegion.
However there can be more than just one window so we need
a "root" memory region to be separated from the actual DMA window(s).

This introduces a "root" IOMMU memory region and adds a subregion for
the default DMA 32bit window. Following patches will add other
subregion(s).

This initializes a default DMA window subregion size to the guest RAM
size as this window can be switched into "bypass" mode which implements
direct DMA mapping.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alexander Graf <agraf@suse.de>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/hw/pci-host/spapr.h b/include/hw/pci-host/spapr.h
index 0f428a1af9..fcb62137a2 100644
--- a/include/hw/pci-host/spapr.h
+++ b/include/hw/pci-host/spapr.h
@@ -64,6 +64,7 @@ struct sPAPRPHBState {
     uint64_t dma_window_size;
     sPAPRTCETable *tcet;
     AddressSpace iommu_as;
+    MemoryRegion iommu_root;
 
     struct spapr_pci_lsi {
         uint32_t irq;