Nothing special is happening here. All important changes were
done when for 'virtio-pmem' (adjusting the code to put virtio
memory on PCI bus, generating alias using
qemuDomainDeviceAliasIndex(). The only bit that might look
suspicious is no prealloc for virtio-mem. But if you think about
it, the whole purpose of this device is to change amount of
memory exposed to guest on the fly. There is no point in locking
the whole backend in memory.
Signed-off-by: Michal Privoznik <mpriv...@redhat.com>
---
src/qemu/qemu_alias.c | 9 +++-
src/qemu/qemu_command.c | 28 +++++++++++--
...mory-hotplug-virtio-mem.x86_64-latest.args | 41 +++++++++++++++++++
tests/qemuxml2argvtest.c | 1 +
4 files changed, 74 insertions(+), 5 deletions(-)
create mode 100644
tests/qemuxml2argvdata/memory-hotplug-virtio-mem.x86_64-latest.args
diff --git a/src/qemu/qemu_alias.c b/src/qemu/qemu_alias.c
index 79e8953b2f..81a1e7eeed 100644
--- a/src/qemu/qemu_alias.c
+++ b/src/qemu/qemu_alias.c
@@ -475,8 +475,11 @@ qemuDeviceMemoryGetAliasID(virDomainDef *def,
size_t i;
int maxidx = 0;
- /* virtio-pmem goes onto PCI bus and thus DIMM address is not valid */
- if (!oldAlias && mem->model != VIR_DOMAIN_MEMORY_MODEL_VIRTIO_PMEM)
+ /* virtio-pmem and virtio-mem go onto PCI bus and thus DIMM address is not
+ * valid */
+ if (!oldAlias &&
+ mem->model != VIR_DOMAIN_MEMORY_MODEL_VIRTIO_PMEM &&
+ mem->model != VIR_DOMAIN_MEMORY_MODEL_VIRTIO_MEM)
return mem->info.addr.dimm.slot;
for (i = 0; i < def->nmems; i++) {
@@ -523,6 +526,8 @@ qemuAssignDeviceMemoryAlias(virDomainDef *def,
prefix = "virtiopmem";
break;
case VIR_DOMAIN_MEMORY_MODEL_VIRTIO_MEM:
+ prefix = "virtiomem";
+ break;
case VIR_DOMAIN_MEMORY_MODEL_NONE:
case VIR_DOMAIN_MEMORY_MODEL_LAST:
default:
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 8beb3cdedc..fb307f3c61 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -3139,9 +3139,23 @@ qemuBuildMemoryBackendProps(virJSONValue **backendProps,
virJSONValueObjectAdd(props, "b:x-use-canonical-path-for-ramblock-id",
false, NULL) < 0)
return -1;
- if (!priv->memPrealloc &&
- virJSONValueObjectAdd(props, "B:prealloc", prealloc, NULL) < 0)
- return -1;
+ if (mem->model == VIR_DOMAIN_MEMORY_MODEL_VIRTIO_MEM) {
+ /* Explicitly disable prealloc for virtio-mem as it's not supported
+ * currently. Warn users if their config would result in prealloc. */
+ if (priv->memPrealloc || prealloc) {
+ VIR_WARN("Memory preallocation is unsupported for virtio-mem
memory devices");
+ }
+ if (priv->memPrealloc &&
+ virJSONValueObjectAppendBoolean(props, "prealloc", 0) < 0)
+ return -1;
+ if (virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_MEMORY_BACKEND_RESERVE) &&
+ virJSONValueObjectAppendBoolean(props, "reserve", 0) < 0)
+ return -1;
+ } else {
+ if (!priv->memPrealloc &&
+ virJSONValueObjectAdd(props, "B:prealloc", prealloc, NULL) < 0)
+ return -1;
+ }
if (virJSONValueObjectAdd(props, "U:size", mem->size * 1024, NULL) < 0)
return -1;
@@ -3321,6 +3335,9 @@ qemuBuildMemoryDeviceStr(const virDomainDef *def,
break;
case VIR_DOMAIN_MEMORY_MODEL_VIRTIO_MEM:
+ device = "virtio-mem-pci";
+ break;
+
case VIR_DOMAIN_MEMORY_MODEL_NONE:
case VIR_DOMAIN_MEMORY_MODEL_LAST:
default:
@@ -3337,6 +3354,11 @@ qemuBuildMemoryDeviceStr(const virDomainDef *def,
if (mem->labelsize)
virBufferAsprintf(&buf, "label-size=%llu,", mem->labelsize * 1024);
+ if (mem->blocksize) {
+ virBufferAsprintf(&buf, "block-size=%llu,", mem->blocksize * 1024);
+ virBufferAsprintf(&buf, "requested-size=%llu,", mem->requestedsize *
1024);
+ }
+
if (mem->uuid) {
char uuidstr[VIR_UUID_STRING_BUFLEN];
diff --git
a/tests/qemuxml2argvdata/memory-hotplug-virtio-mem.x86_64-latest.args
b/tests/qemuxml2argvdata/memory-hotplug-virtio-mem.x86_64-latest.args
new file mode 100644
index 0000000000..22ee1bc459
--- /dev/null
+++ b/tests/qemuxml2argvdata/memory-hotplug-virtio-mem.x86_64-latest.args
@@ -0,0 +1,41 @@
+LC_ALL=C \
+PATH=/bin \
+HOME=/tmp/lib/domain--1-QEMUGuest1 \
+USER=test \
+LOGNAME=test \
+XDG_DATA_HOME=/tmp/lib/domain--1-QEMUGuest1/.local/share \
+XDG_CACHE_HOME=/tmp/lib/domain--1-QEMUGuest1/.cache \
+XDG_CONFIG_HOME=/tmp/lib/domain--1-QEMUGuest1/.config \
+/usr/bin/qemu-system-i386 \
+-name guest=QEMUGuest1,debug-threads=on \
+-S \
+-object
'{"qom-type":"secret","id":"masterKey0","format":"raw","file":"/tmp/lib/domain--1-QEMUGuest1/master-key.aes"}'
\
+-machine pc,accel=kvm,usb=off,dump-guest-core=off \
+-cpu qemu64 \
+-m size=2095104k,slots=16,maxmem=1099511627776k \
+-overcommit mem-lock=off \
+-smp 2,sockets=2,dies=1,cores=1,threads=1 \
+-object '{"qom-type":"memory-backend-ram","id":"ram-node0","size":2145386496}'
\
+-numa node,nodeid=0,cpus=0-1,memdev=ram-node0 \
+-object
'{"qom-type":"memory-backend-ram","id":"memvirtiomem0","reserve":false,"size":1073741824}'
\
+-device
virtio-mem-pci,node=0,block-size=2097152,requested-size=536870912,memdev=memvirtiomem0,id=virtiomem0,bus=pci.0,addr=0x2
\
+-object
'{"qom-type":"memory-backend-file","id":"memvirtiomem1","mem-path":"/dev/hugepages2M/libvirt/qemu/-1-QEMUGuest1","reserve":false,"size":2147483648,"host-nodes":[1,2,3],"policy":"bind"}'
\
+-device
virtio-mem-pci,node=0,block-size=2097152,requested-size=1073741824,memdev=memvirtiomem1,id=virtiomem1,bus=pci.0,addr=0x3
\
+-uuid c7a5fdbd-edaf-9455-926a-d65c16db1809 \
+-display none \
+-no-user-config \
+-nodefaults \
+-chardev socket,id=charmonitor,fd=1729,server=on,wait=off \
+-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 \
+-blockdev
'{"driver":"host_device","filename":"/dev/HostVG/QEMUGuest1","node-name":"libvirt-1-storage","auto-read-only":true,"discard":"unmap"}'
\
+-blockdev
'{"node-name":"libvirt-1-format","read-only":false,"driver":"raw","file":"libvirt-1-storage"}'
\
+-device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1
\
+-audiodev id=audio1,driver=none \
+-device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x4 \
+-sandbox
on,obsolete=deny,elevateprivileges=deny,spawn=deny,resourcecontrol=deny \
+-msg timestamp=on
diff --git a/tests/qemuxml2argvtest.c b/tests/qemuxml2argvtest.c
index 18b7b0ecf1..c375d7e895 100644
--- a/tests/qemuxml2argvtest.c
+++ b/tests/qemuxml2argvtest.c
@@ -3137,6 +3137,7 @@ mymain(void)
ARG_END);
DO_TEST_CAPS_VER("memory-hotplug-virtio-pmem", "5.2.0");
DO_TEST_CAPS_LATEST("memory-hotplug-virtio-pmem");
+ DO_TEST_CAPS_LATEST("memory-hotplug-virtio-mem");
DO_TEST("machine-aeskeywrap-on-caps",
QEMU_CAPS_AES_KEY_WRAP,
--
2.32.0
