pc-dimm: assign and verify the "addr" property during pre_plug

We can assign and verify the address before realizing and trying to plug.
reading/writing the address property should never fail for DIMMs, so let's
reduce error handling a bit by using &error_abort. Getting access to the
memory region now might however fail. So forward errors from
get_memory_region() properly.

As all memory devices should use the alignment of the underlying memory
region for guest physical address asignment, do detection of the
alignment in pc_dimm_pre_plug(), but allow pc.c to overwrite the
alignment for compatibility handling.

Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180801133444.11269-5-david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 26 insertions, 24 deletions

diff --git a/hw/mem/pc-dimm.c b/hw/mem/pc-dimm.c
index e56c4da..fb6bcae 100644
--- a/hw/mem/pc-dimm.c
+++ b/hw/mem/pc-dimm.c
@@ -29,9 +29,14 @@
 
 static int pc_dimm_get_free_slot(const int *hint, int max_slots, Error **errp);
 
-void pc_dimm_pre_plug(DeviceState *dev, MachineState *machine, Error **errp)
+void pc_dimm_pre_plug(DeviceState *dev, MachineState *machine,
+                      const uint64_t *legacy_align, Error **errp)
 {
+    PCDIMMDevice *dimm = PC_DIMM(dev);
+    PCDIMMDeviceClass *ddc = PC_DIMM_GET_CLASS(dimm);
     Error *local_err = NULL;
+    MemoryRegion *mr;
+    uint64_t addr, align;
     int slot;
 
     slot = object_property_get_int(OBJECT(dev), PC_DIMM_SLOT_PROP,
@@ -43,44 +48,41 @@ void pc_dimm_pre_plug(DeviceState *dev, MachineState *machine, Error **errp)
     }
     object_property_set_int(OBJECT(dev), slot, PC_DIMM_SLOT_PROP, &error_abort);
     trace_mhp_pc_dimm_assigned_slot(slot);
+
+    mr = ddc->get_memory_region(dimm, &local_err);
+    if (local_err) {
+        goto out;
+    }
+
+    align = legacy_align ? *legacy_align : memory_region_get_alignment(mr);
+    addr = object_property_get_uint(OBJECT(dev), PC_DIMM_ADDR_PROP,
+                                    &error_abort);
+    addr = memory_device_get_free_addr(machine, !addr ? NULL : &addr, align,
+                                       memory_region_size(mr), &local_err);
+    if (local_err) {
+        goto out;
+    }
+    trace_mhp_pc_dimm_assigned_address(addr);
+    object_property_set_uint(OBJECT(dev), addr, PC_DIMM_ADDR_PROP,
+                             &error_abort);
 out:
     error_propagate(errp, local_err);
 }
 
-void pc_dimm_plug(DeviceState *dev, MachineState *machine, uint64_t align,
-                  Error **errp)
+void pc_dimm_plug(DeviceState *dev, MachineState *machine, Error **errp)
 {
     PCDIMMDevice *dimm = PC_DIMM(dev);
     PCDIMMDeviceClass *ddc = PC_DIMM_GET_CLASS(dimm);
     MemoryRegion *vmstate_mr = ddc->get_vmstate_memory_region(dimm,
                                                               &error_abort);
     MemoryRegion *mr = ddc->get_memory_region(dimm, &error_abort);
-    Error *local_err = NULL;
     uint64_t addr;
 
-    addr = object_property_get_uint(OBJECT(dimm),
-                                    PC_DIMM_ADDR_PROP, &local_err);
-    if (local_err) {
-        goto out;
-    }
-
-    addr = memory_device_get_free_addr(machine, !addr ? NULL : &addr, align,
-                                       memory_region_size(mr), &local_err);
-    if (local_err) {
-        goto out;
-    }
-
-    object_property_set_uint(OBJECT(dev), addr, PC_DIMM_ADDR_PROP, &local_err);
-    if (local_err) {
-        goto out;
-    }
-    trace_mhp_pc_dimm_assigned_address(addr);
+    addr = object_property_get_uint(OBJECT(dev), PC_DIMM_ADDR_PROP,
+                                    &error_abort);
 
     memory_device_plug_region(machine, mr, addr);
     vmstate_register_ram(vmstate_mr, dev);
-
-out:
-    error_propagate(errp, local_err);
 }
 
 void pc_dimm_unplug(DeviceState *dev, MachineState *machine)