memory-device: add and use memory_device_get_region_size()

We will factor out get_memory_region() from pc-dimm to memory device code
soon. Once that is done, get_region_size() can be implemented
generically and essentially be replaced by
memory_device_get_region_size (and work only on get_memory_region()).

We have some users of get_memory_region() (spapr and pc-dimm code) that are
only interested in the size. So let's rework them to use
memory_device_get_region_size() first, then we can factor out
get_memory_region() and eventually remove get_region_size() without
touching the same code multiple times.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20181005092024.14344-10-david@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>

3 files changed, 21 insertions, 23 deletions

diff --git a/hw/mem/memory-device.c b/hw/mem/memory-device.c
index c1e1b81..425830c 100644
--- a/hw/mem/memory-device.c
+++ b/hw/mem/memory-device.c
@@ -57,10 +57,9 @@ static int memory_device_used_region_size(Object *obj, void *opaque)
     if (object_dynamic_cast(obj, TYPE_MEMORY_DEVICE)) {
         const DeviceState *dev = DEVICE(obj);
         const MemoryDeviceState *md = MEMORY_DEVICE(obj);
-        const MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(obj);
 
         if (dev->realized) {
-            *size += mdc->get_region_size(md, &error_abort);
+            *size += memory_device_get_region_size(md, &error_abort);
         }
     }
 
@@ -167,7 +166,7 @@ uint64_t memory_device_get_free_addr(MachineState *ms, const uint64_t *hint,
         uint64_t md_size, md_addr;
 
         md_addr = mdc->get_addr(md);
-        md_size = mdc->get_region_size(md, &error_abort);
+        md_size = memory_device_get_region_size(md, &error_abort);
 
         if (ranges_overlap(md_addr, md_size, new_addr, size)) {
             if (hint) {
@@ -266,6 +265,14 @@ void memory_device_unplug_region(MachineState *ms, MemoryRegion *mr)
     memory_region_del_subregion(&ms->device_memory->mr, mr);
 }
 
+uint64_t memory_device_get_region_size(const MemoryDeviceState *md,
+                                       Error **errp)
+{
+    MemoryDeviceClass *mdc = MEMORY_DEVICE_GET_CLASS(md);
+
+    return mdc->get_region_size(md, errp);
+}
+
 static const TypeInfo memory_device_info = {
     .name          = TYPE_MEMORY_DEVICE,
     .parent        = TYPE_INTERFACE,
diff --git a/hw/mem/pc-dimm.c b/hw/mem/pc-dimm.c
index 130f78d..3e43ec8 100644
--- a/hw/mem/pc-dimm.c
+++ b/hw/mem/pc-dimm.c
@@ -161,16 +161,14 @@ static Property pc_dimm_properties[] = {
 static void pc_dimm_get_size(Object *obj, Visitor *v, const char *name,
                              void *opaque, Error **errp)
 {
+    Error *local_err = NULL;
     uint64_t value;
-    MemoryRegion *mr;
-    PCDIMMDevice *dimm = PC_DIMM(obj);
-    PCDIMMDeviceClass *ddc = PC_DIMM_GET_CLASS(obj);
 
-    mr = ddc->get_memory_region(dimm, errp);
-    if (!mr) {
+    value = memory_device_get_region_size(MEMORY_DEVICE(obj), &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
         return;
     }
-    value = memory_region_size(mr);
 
     visit_type_uint64(v, name, &value, errp);
 }
diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index c078347..c08130f 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -3128,12 +3128,10 @@ static void spapr_memory_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
     Error *local_err = NULL;
     sPAPRMachineState *ms = SPAPR_MACHINE(hotplug_dev);
     PCDIMMDevice *dimm = PC_DIMM(dev);
-    PCDIMMDeviceClass *ddc = PC_DIMM_GET_CLASS(dimm);
-    MemoryRegion *mr = ddc->get_memory_region(dimm, &error_abort);
     uint64_t size, addr;
     uint32_t node;
 
-    size = memory_region_size(mr);
+    size = memory_device_get_region_size(MEMORY_DEVICE(dev), &error_abort);
 
     pc_dimm_plug(dimm, MACHINE(ms), &local_err);
     if (local_err) {
@@ -3169,9 +3167,7 @@ static void spapr_memory_pre_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
     const sPAPRMachineClass *smc = SPAPR_MACHINE_GET_CLASS(hotplug_dev);
     sPAPRMachineState *spapr = SPAPR_MACHINE(hotplug_dev);
     PCDIMMDevice *dimm = PC_DIMM(dev);
-    PCDIMMDeviceClass *ddc = PC_DIMM_GET_CLASS(dimm);
     Error *local_err = NULL;
-    MemoryRegion *mr;
     uint64_t size;
     Object *memdev;
     hwaddr pagesize;
@@ -3181,11 +3177,11 @@ static void spapr_memory_pre_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
         return;
     }
 
-    mr = ddc->get_memory_region(dimm, errp);
-    if (!mr) {
+    size = memory_device_get_region_size(MEMORY_DEVICE(dimm), &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
         return;
     }
-    size = memory_region_size(mr);
 
     if (size % SPAPR_MEMORY_BLOCK_SIZE) {
         error_setg(errp, "Hotplugged memory size must be a multiple of "
@@ -3257,9 +3253,8 @@ static sPAPRDIMMState *spapr_recover_pending_dimm_state(sPAPRMachineState *ms,
                                                         PCDIMMDevice *dimm)
 {
     sPAPRDRConnector *drc;
-    PCDIMMDeviceClass *ddc = PC_DIMM_GET_CLASS(dimm);
-    MemoryRegion *mr = ddc->get_memory_region(dimm, &error_abort);
-    uint64_t size = memory_region_size(mr);
+    uint64_t size = memory_device_get_region_size(MEMORY_DEVICE(dimm),
+                                                  &error_abort);
     uint32_t nr_lmbs = size / SPAPR_MEMORY_BLOCK_SIZE;
     uint32_t avail_lmbs = 0;
     uint64_t addr_start, addr;
@@ -3325,14 +3320,12 @@ static void spapr_memory_unplug_request(HotplugHandler *hotplug_dev,
     sPAPRMachineState *spapr = SPAPR_MACHINE(hotplug_dev);
     Error *local_err = NULL;
     PCDIMMDevice *dimm = PC_DIMM(dev);
-    PCDIMMDeviceClass *ddc = PC_DIMM_GET_CLASS(dimm);
-    MemoryRegion *mr = ddc->get_memory_region(dimm, &error_abort);
     uint32_t nr_lmbs;
     uint64_t size, addr_start, addr;
     int i;
     sPAPRDRConnector *drc;
 
-    size = memory_region_size(mr);
+    size = memory_device_get_region_size(MEMORY_DEVICE(dimm), &error_abort);
     nr_lmbs = size / SPAPR_MEMORY_BLOCK_SIZE;
 
     addr_start = object_property_get_uint(OBJECT(dimm), PC_DIMM_ADDR_PROP,