qemu: Assign slots to memory devices prior to usage

As with other devices assign the slot number right away when adding the
device. This will make the slot numbers static as we do with other
addressing elements and it will ultimately simplify allocation of the
alias in a static way which does not break with qemu.

src/qemu/qemu_domain_address.c

@@ -1748,6 +1748,94 @@ qemuDomainUSBAddressAddHubs(virDomainDefPtr def)
 }
 
 
+static virBitmapPtr
+qemuDomainGetMemorySlotMap(const virDomainDef *def)
+{
+    virBitmapPtr ret;
+    virDomainMemoryDefPtr mem;
+    size_t i;
+
+    if (!(ret = virBitmapNew(def->mem.memory_slots)))
+        return NULL;
+
+    for (i = 0; i < def->nmems; i++) {
+        mem = def->mems[i];
+
+        if (mem->info.type == VIR_DOMAIN_DEVICE_ADDRESS_TYPE_DIMM)
+            ignore_value(virBitmapSetBit(ret, mem->info.addr.dimm.slot));
+    }
+
+    return ret;
+}
+
+
+static int
+qemuAssignMemoryDeviceSlot(virDomainMemoryDefPtr mem,
+                           virBitmapPtr slotmap)
+{
+    ssize_t nextslot = -1;
+
+    if (mem->info.type == VIR_DOMAIN_DEVICE_ADDRESS_TYPE_DIMM)
+        return 0;
+
+    if ((nextslot = virBitmapNextClearBit(slotmap, -1)) < 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                       _("failed to find a emtpy memory slot"));
+        return -1;
+    }
+
+    ignore_value(virBitmapSetBit(slotmap, nextslot));
+    mem->info.type = VIR_DOMAIN_DEVICE_ADDRESS_TYPE_DIMM;
+    mem->info.addr.dimm.slot = nextslot;
+
+    return 0;
+}
+
+
+int
+qemuDomainAssignMemoryDeviceSlot(virDomainDefPtr def,
+                                 virDomainMemoryDefPtr mem)
+{
+    virBitmapPtr slotmap = NULL;
+    int ret;
+
+    if (!(slotmap = qemuDomainGetMemorySlotMap(def)))
+        return -1;
+
+    ret = qemuAssignMemoryDeviceSlot(mem, slotmap);
+
+    virBitmapFree(slotmap);
+    return ret;
+}
+
+
+static int
+qemuDomainAssignMemorySlots(virDomainDefPtr def)
+{
+    virBitmapPtr slotmap = NULL;
+    int ret = -1;
+    size_t i;
+
+    if (!virDomainDefHasMemoryHotplug(def))
+        return 0;
+
+    if (!(slotmap = qemuDomainGetMemorySlotMap(def)))
+        return -1;
+
+    for (i = 0; i < def->nmems; i++) {
+        if (qemuAssignMemoryDeviceSlot(def->mems[i], slotmap) < 0)
+            goto cleanup;
+    }
+
+    ret = 0;
+
+ cleanup:
+    virBitmapFree(slotmap);
+    return ret;
+
+}
+
+
 static int
 qemuDomainAssignUSBAddresses(virDomainDefPtr def,
                              virDomainObjPtr obj,
@@ -1827,6 +1915,9 @@ qemuDomainAssignAddresses(virDomainDefPtr def,
     if (qemuDomainAssignUSBAddresses(def, obj, newDomain) < 0)
         return -1;
 
+    if (qemuDomainAssignMemorySlots(def) < 0)
+        return -1;
+
     return 0;
 }
 

src/qemu/qemu_domain_address.h

@@ -45,6 +45,10 @@ virDomainCCWAddressSetPtr
 qemuDomainCCWAddrSetCreateFromDomain(virDomainDefPtr def)
     ATTRIBUTE_NONNULL(1);
 
+int qemuDomainAssignMemoryDeviceSlot(virDomainDefPtr def,
+                                     virDomainMemoryDefPtr mem);
+
+
 # define __QEMU_DOMAIN_ADDRESS_H__
 
 #endif /* __QEMU_DOMAIN_ADDRESS_H__ */

src/qemu/qemu_hotplug.c

@@ -2132,6 +2132,9 @@ qemuDomainAttachMemory(virQEMUDriverPtr driver,
     if (qemuDomainDefValidateMemoryHotplug(vm->def, priv->qemuCaps, mem) < 0)
         goto cleanup;
 
+    if (qemuDomainAssignMemoryDeviceSlot(vm->def, mem) < 0)
+        goto cleanup;
+
     if (qemuAssignDeviceMemoryAlias(vm->def, mem) < 0)
         goto cleanup;
 

tests/qemuxml2argvdata/qemuxml2argv-hugepages-numa.args

@@ -16,7 +16,7 @@ QEMU_AUDIO_DRV=spice \
 -object memory-backend-file,id=memdimm0,prealloc=yes,\
 mem-path=/dev/hugepages1G/libvirt/qemu,size=1073741824,host-nodes=1-3,\
 policy=bind \
--device pc-dimm,node=0,memdev=memdimm0,id=dimm0 \
+-device pc-dimm,node=0,memdev=memdimm0,id=dimm0,slot=0 \
 -uuid 63840878-0deb-4095-97e6-fc444d9bc9fa \
 -nodefaults \
 -monitor unix:/tmp/lib/domain--1-fedora/monitor.sock,server,nowait \

tests/qemuxml2argvdata/qemuxml2argv-memory-hotplug-dimm.args

@@ -12,11 +12,11 @@ QEMU_AUDIO_DRV=none \
 -smp 2,sockets=2,cores=1,threads=1 \
 -numa node,nodeid=0,cpus=0-1,mem=214 \
 -object memory-backend-ram,id=memdimm0,size=536870912 \
--device pc-dimm,node=0,memdev=memdimm0,id=dimm0 \
+-device pc-dimm,node=0,memdev=memdimm0,id=dimm0,slot=0 \
 -object memory-backend-file,id=memdimm1,prealloc=yes,\
 mem-path=/dev/hugepages2M/libvirt/qemu,size=536870912,host-nodes=1-3,\
 policy=bind \
--device pc-dimm,node=0,memdev=memdimm1,id=dimm1 \
+-device pc-dimm,node=0,memdev=memdimm1,id=dimm1,slot=1 \
 -uuid c7a5fdbd-edaf-9455-926a-d65c16db1809 \
 -nographic \
 -nodefaults \

tests/qemuxml2argvdata/qemuxml2argv-memory-hotplug-ppc64-nonuma.args

@@ -11,9 +11,9 @@ QEMU_AUDIO_DRV=none \
 -m size=1310720k,slots=16,maxmem=4194304k \
 -smp 1,sockets=1,cores=1,threads=1 \
 -object memory-backend-ram,id=memdimm0,size=536870912 \
--device pc-dimm,memdev=memdimm0,id=dimm0 \
+-device pc-dimm,memdev=memdimm0,id=dimm0,slot=0 \
 -object memory-backend-ram,id=memdimm1,size=536870912 \
--device pc-dimm,memdev=memdimm1,id=dimm1 \
+-device pc-dimm,memdev=memdimm1,id=dimm1,slot=1 \
 -uuid 49545eb3-75e1-2d0a-acdd-f0294406c99e \
 -nographic \
 -nodefaults \

tests/qemuxml2xmloutdata/qemuxml2xmlout-memory-hotplug-dimm.xml

@@ -47,6 +47,7 @@
         <size unit='KiB'>523264</size>
         <node>0</node>
       </target>
+      <address type='dimm' slot='0'/>
     </memory>
     <memory model='dimm'>
       <source>
@@ -57,6 +58,7 @@
         <size unit='KiB'>524287</size>
         <node>0</node>
       </target>
+      <address type='dimm' slot='1'/>
     </memory>
   </devices>
 </domain>