spapr_vio/spapr_iommu: Move VIO bypass where it belongs

Instead of tweaking a TCE table device by adding there a bypass flag,
let's add an alias to RAM and IOMMU memory region, and enable/disable
those according to the selected bypass mode.
This way IOMMU memory region can have size of the actual window rather
than ram_size which is essential for upcoming DDW support.

This moves bypass logic to VIO layer and keeps @bypass flag in TCE table
for migration compatibility only. This replaces spapr_tce_set_bypass()
calls with explicit assignment to avoid confusion as the function could
do something more that just syncing the @bypass flag.

This adds a pointer to VIO device into the sPAPRTCETable struct to provide
the sPAPRTCETable device a way to update bypass mode for the VIO device.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>

1 files changed, 4 insertions, 0 deletions

diff --git a/include/hw/ppc/spapr_vio.h b/include/hw/ppc/spapr_vio.h
index 46edc2a20c..222397ddc6 100644
--- a/include/hw/ppc/spapr_vio.h
+++ b/include/hw/ppc/spapr_vio.h
@@ -64,6 +64,8 @@ struct VIOsPAPRDevice {
     target_ulong signal_state;
     VIOsPAPR_CRQ crq;
     AddressSpace as;
+    MemoryRegion mrroot;
+    MemoryRegion mrbypass;
     sPAPRTCETable *tcet;
 };
 
@@ -139,4 +141,6 @@ extern const VMStateDescription vmstate_spapr_vio;
 #define VMSTATE_SPAPR_VIO(_f, _s) \
     VMSTATE_STRUCT(_f, _s, 0, vmstate_spapr_vio, VIOsPAPRDevice)
 
+void spapr_vio_set_bypass(VIOsPAPRDevice *dev, bool bypass);
+
 #endif /* _HW_SPAPR_VIO_H */