[Qemu-devel] [PATCH v1 4/4] pc-dimm: assign and verify the "addr" property during pre_plug

[David Hildenbrand]

We can assign and verify the slot before realizing and trying to plug.
reading/writing the address property should never fail, 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.

Keep tracing the assigned address for now in the plug code, as that's the
point we are sure plugging succeeded and the address willa ctually be
used.

Signed-off-by: David Hildenbrand <da...@redhat.com>
---
 hw/mem/pc-dimm.c | 43 ++++++++++++++++++++++---------------------
 1 file changed, 22 insertions(+), 21 deletions(-)

diff --git a/hw/mem/pc-dimm.c b/hw/mem/pc-dimm.c
index 9198104d34..42c4d0b750 100644
--- a/hw/mem/pc-dimm.c
+++ b/hw/mem/pc-dimm.c
@@ -31,7 +31,11 @@ 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)
 {
+    PCDIMMDevice *dimm = PC_DIMM(dev);
+    PCDIMMDeviceClass *ddc = PC_DIMM_GET_CLASS(dimm);
     Error *local_err = NULL;
+    uint64_t align, addr;
+    MemoryRegion *mr;
     int slot;
 
     slot = object_property_get_int(OBJECT(dev), PC_DIMM_SLOT_PROP,
@@ -43,6 +47,22 @@ 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 = memory_device_get_align(machine, 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;
+    }
+    object_property_set_uint(OBJECT(dev), addr, PC_DIMM_ADDR_PROP,
+                             &error_abort);
 out:
     error_propagate(errp, local_err);
 }
@@ -54,33 +74,14 @@ void pc_dimm_plug(DeviceState *dev, MachineState *machine, 
Error **errp)
     MemoryRegion *vmstate_mr = ddc->get_vmstate_memory_region(dimm,
                                                               &error_abort);
     MemoryRegion *mr = ddc->get_memory_region(dimm, &error_abort);
-    const uint64_t align = memory_device_get_align(machine, mr);
-    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;
-    }
+    addr = object_property_get_uint(OBJECT(dev), PC_DIMM_ADDR_PROP,
+                                    &error_abort);
     trace_mhp_pc_dimm_assigned_address(addr);
 
     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)
-- 
2.17.1