From: Marc-André Lureau <marcandre.lureau(a)redhat.com>
When the memory is shared and the source isn't specified to be a file,
we can make use of memory-backend-memfd. Sealing is enabled by default
in qemu, hugepage is easier to setup, which makes it a better choice
than memory-backend-file.
Signed-off-by: Marc-André Lureau <marcandre.lureau(a)redhat.com>
---
src/qemu/qemu_command.c | 20 ++++++++++++++++---
tests/qemuxml2argvdata/memfd.args | 28 +++++++++++++++++++++++++++
tests/qemuxml2argvdata/memfd.xml | 32 +++++++++++++++++++++++++++++++
tests/qemuxml2argvtest.c | 2 ++
4 files changed, 79 insertions(+), 3 deletions(-)
create mode 100644 tests/qemuxml2argvdata/memfd.args
create mode 100644 tests/qemuxml2argvdata/memfd.xml
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index f1235099b2..45ab1f85ae 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -3137,7 +3137,21 @@ qemuBuildMemoryBackendProps(virJSONValuePtr *backendProps,
if (!(props = virJSONValueNewObject()))
return -1;
- if (useHugepage || mem->nvdimmPath || memAccess ||
+ if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_OBJECT_MEMORY_MEMFD) &&
+ memAccess == VIR_DOMAIN_MEMORY_ACCESS_SHARED &&
+ !mem->nvdimmPath &&
+ def->mem.source != VIR_DOMAIN_MEMORY_SOURCE_FILE) {
+
+ backendType = "memory-backend-memfd";
+
+ if (useHugepage &&
+ virJSONValueObjectAdd(props,
+ "b:hugetlb", true,
+ "U:hugetlbsize", pagesize * 1024,
+ NULL) < 0)
+ goto cleanup;
+
+ } else if (useHugepage || mem->nvdimmPath || memAccess ||
def->mem.source == VIR_DOMAIN_MEMORY_SOURCE_FILE) {
if (useHugepage) {
@@ -7670,8 +7684,8 @@ qemuBuildNumaArgStr(virQEMUDriverConfigPtr cfg,
* need to check which approach to use */
for (i = 0; i < ncells; i++) {
if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_OBJECT_MEMORY_RAM) ||
- virQEMUCapsGet(qemuCaps, QEMU_CAPS_OBJECT_MEMORY_FILE)) {
-
+ virQEMUCapsGet(qemuCaps, QEMU_CAPS_OBJECT_MEMORY_FILE) ||
+ virQEMUCapsGet(qemuCaps, QEMU_CAPS_OBJECT_MEMORY_MEMFD)) {
if (implicit)
rc = qemuBuildMemoryBackendStr(def, cfg, "ram-node", -1,
diff --git a/tests/qemuxml2argvdata/memfd.args b/tests/qemuxml2argvdata/memfd.args
new file mode 100644
index 0000000000..dda8e272ea
--- /dev/null
+++ b/tests/qemuxml2argvdata/memfd.args
@@ -0,0 +1,28 @@
+LC_ALL=C \
+PATH=/bin \
+HOME=/home/test \
+USER=test \
+LOGNAME=test \
+QEMU_AUDIO_DRV=none \
+/usr/bin/qemu-system-i686 \
+-name QEMUGuest1 \
+-S \
+-machine pc,accel=tcg,usb=off,dump-guest-core=off \
+-m 214 \
+-smp 1,sockets=1,cores=1,threads=1 \
+-object memory-backend-memfd,id=ram-node,size=224395264 \
+-numa node,nodeid=0,memdev=ram-node \
+-uuid c7a5fdbd-edaf-9455-926a-d65c16db1809 \
+-display none \
+-no-user-config \
+-nodefaults \
+-chardev
socket,id=charmonitor,path=/tmp/lib/domain--1-QEMUGuest1/monitor.sock,server,nowait \
+-mon chardev=charmonitor,id=monitor,mode=control \
+-rtc base=utc \
+-no-shutdown \
+-no-acpi \
+-boot c \
+-usb \
+-drive file=/dev/HostVG/QEMUGuest1,format=raw,if=none,id=drive-ide0-0-0 \
+-device ide-drive,bus=ide.0,unit=0,drive=drive-ide0-0-0,id=ide0-0-0 \
+-device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3
diff --git a/tests/qemuxml2argvdata/memfd.xml b/tests/qemuxml2argvdata/memfd.xml
new file mode 100644
index 0000000000..c60b169169
--- /dev/null
+++ b/tests/qemuxml2argvdata/memfd.xml
@@ -0,0 +1,32 @@
+<domain type='qemu'>
+ <name>QEMUGuest1</name>
+ <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid>
+ <memory unit='KiB'>219136</memory>
+ <currentMemory unit='KiB'>219136</currentMemory>
+ <memoryBacking>
+ <access mode='shared'/>
+ </memoryBacking>
+ <vcpu placement='static'>1</vcpu>
+ <os>
+ <type arch='i686' machine='pc'>hvm</type>
+ <boot dev='hd'/>
+ </os>
+ <clock offset='utc'/>
+ <on_poweroff>destroy</on_poweroff>
+ <on_reboot>restart</on_reboot>
+ <on_crash>destroy</on_crash>
+ <devices>
+ <emulator>/usr/bin/qemu-system-i686</emulator>
+ <disk type='block' device='disk'>
+ <source dev='/dev/HostVG/QEMUGuest1'/>
+ <target dev='hda' bus='ide'/>
+ <address type='drive' controller='0' bus='0'
target='0' unit='0'/>
+ </disk>
+ <controller type='usb' index='0'/>
+ <controller type='ide' index='0'/>
+ <controller type='pci' index='0' model='pci-root'/>
+ <input type='mouse' bus='ps2'/>
+ <input type='keyboard' bus='ps2'/>
+ <memballoon model='virtio'/>
+ </devices>
+</domain>
diff --git a/tests/qemuxml2argvtest.c b/tests/qemuxml2argvtest.c
index a929e4314e..47bd2ab867 100644
--- a/tests/qemuxml2argvtest.c
+++ b/tests/qemuxml2argvtest.c
@@ -945,6 +945,8 @@ mymain(void)
DO_TEST("pmu-feature", NONE);
DO_TEST("pmu-feature-off", NONE);
+ DO_TEST("memfd",
+ QEMU_CAPS_OBJECT_MEMORY_MEMFD);
DO_TEST("hugepages", NONE);
DO_TEST("hugepages-numa",
QEMU_CAPS_PIIX_DISABLE_S3, QEMU_CAPS_PIIX_DISABLE_S4,
--
2.18.0.129.ge3331758f1