qemu: Add command-line to generate the nvdimm pmem property

According to the result parsing from xml, add pmem property
into QEMU command line:

-object memory-backend-file,...[,pmem=on]
Signed-off-by: NLuyao Zhong <luyao.zhong@intel.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

src/qemu/qemu_command.c

@@ -3409,6 +3409,17 @@ qemuBuildMemoryBackendProps(virJSONValuePtr *backendProps,
             goto cleanup;
     }
 
+    if (mem->nvdimmPmem) {
+        if (!virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_OBJECT_MEMORY_FILE_PMEM)) {
+            virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+                           _("nvdimm pmem property is not available "
+                             "with this QEMU binary"));
+            goto cleanup;
+        }
+        if (virJSONValueObjectAdd(props, "s:pmem", "on", NULL) < 0)
+            goto cleanup;
+    }
+
     if (mem->sourceNodes) {
         nodemask = mem->sourceNodes;
     } else {

tests/qemuxml2argvdata/memory-hotplug-nvdimm-pmem.x86_64-latest.args

+LC_ALL=C \
+PATH=/bin \
+HOME=/home/test \
+USER=test \
+LOGNAME=test \
+QEMU_AUDIO_DRV=none \
+/usr/bin/qemu-system-i686 \
+-name guest=QEMUGuest1,debug-threads=on \
+-S \
+-object secret,id=masterKey0,format=raw,\
+file=/tmp/lib/domain--1-QEMUGuest1/master-key.aes \
+-machine pc,accel=tcg,usb=off,dump-guest-core=off,nvdimm=on \
+-m size=219136k,slots=16,maxmem=1099511627776k \
+-realtime mlock=off \
+-smp 2,sockets=2,cores=1,threads=1 \
+-numa node,nodeid=0,cpus=0-1,mem=214 \
+-object memory-backend-file,id=memnvdimm0,prealloc=yes,mem-path=/tmp/nvdimm,\
+share=no,size=536870912,pmem=on \
+-device nvdimm,node=0,memdev=memnvdimm0,id=nvdimm0,slot=0 \
+-uuid c7a5fdbd-edaf-9455-926a-d65c16db1809 \
+-display none \
+-no-user-config \
+-nodefaults \
+-chardev socket,id=charmonitor,fd=1729,server,nowait \
+-mon chardev=charmonitor,id=monitor,mode=control \
+-rtc base=utc \
+-no-shutdown \
+-no-acpi \
+-boot strict=on \
+-device piix3-usb-uhci,id=usb,bus=pci.0,addr=0x1.0x2 \
+-drive file=/dev/HostVG/QEMUGuest1,format=raw,if=none,id=drive-ide0-0-0 \
+-device ide-hd,bus=ide.0,unit=0,drive=drive-ide0-0-0,id=ide0-0-0,bootindex=1 \
+-device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3 \
+-sandbox on,obsolete=deny,elevateprivileges=deny,spawn=deny,\
+resourcecontrol=deny \
+-msg timestamp=on

tests/qemuxml2argvtest.c

@@ -2759,6 +2759,7 @@ mymain(void)
     DO_TEST_CAPS_LATEST("memory-hotplug-nvdimm-access");
     DO_TEST_CAPS_LATEST("memory-hotplug-nvdimm-label");
     DO_TEST_CAPS_LATEST("memory-hotplug-nvdimm-align");
+    DO_TEST_CAPS_LATEST("memory-hotplug-nvdimm-pmem");
 
     DO_TEST("machine-aeskeywrap-on-caps",
             QEMU_CAPS_AES_KEY_WRAP,