libvirt/libvirt-qemu-Implement-support-for-persistent-reservation-migration-control.patch
Jiri Denemark e043cfc857 libvirt-11.10.0-9.el10
- qemu: capabilities: Probe properties of 'scsi-block' and 'scsi-generic' devices (RHEL-135115)
- qemu: capabilities: Introduce QEMU_CAPS_DEVICE_SCSI_BLOCK_MIGRATE_PR (RHEL-135115)
- RHEL-ONLY: backport test data for 'migrate-pr' capability of 'scsi-block' (RHEL-135115)
- qemu: Implement support for persistent reservation migration control (RHEL-135115)
- qemu: Extract disk setup done via QMP into a separate helper (RHEL-131335)
- qemu: process: Rename 'qemuProcessSetupDiskThrottling' to 'qemuProcessSetupDisks' (RHEL-131335)
- qemu: monitor: Extract block latency histogram stats into 'qemuBlockStats' (RHEL-131335)
- Expose latency histograms via 'virConnectGetAllDomainStats' (RHEL-131335)
- qemu: monitor: Add handlers for 'block-latency-histogram-set' (RHEL-131335)
- docs: formatdomain: Fix indentation of docs for <disk><driver><statistics> element (RHEL-131335)
- docs: formatdomain: Reword section about the '<statistics>' element under disk driver (RHEL-131335)
- Introduce support for disk operation latency histogram collection (RHEL-131335)
- qemu: Setup disk latency histograms on startup/hotplug/update (RHEL-131335)

Resolves: RHEL-131335, RHEL-135115
2026-02-17 14:58:02 +01:00

221 lines
9.9 KiB
Diff

From 3f03b1cbc20d0af7900cc43cc576a356a95a292b Mon Sep 17 00:00:00 2001
Message-ID: <3f03b1cbc20d0af7900cc43cc576a356a95a292b.1771336681.git.jdenemar@redhat.com>
From: Peter Krempa <pkrempa@redhat.com>
Date: Thu, 11 Dec 2025 19:47:16 +0100
Subject: [PATCH] qemu: Implement support for persistent reservation migration
control
The 'migration' attribute for the '<reservations>' element allows to
control the persistent reservation migration feature independently of
the machine type default.
Add the XML plumbing and qemu support.
We consider it ABI for now since it influences qemu migration protocol.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
(cherry picked from commit 0d3ef7cb71979172de2c531d865e4525a314f902)
https://issues.redhat.com/browse/RHEL-140614 [rhel-9.8]
https://issues.redhat.com/browse/RHEL-135115 [rhel-10.2]
---
docs/formatdomain.rst | 3 +++
src/conf/domain_conf.c | 21 +++++++++++++++++++
src/conf/schemas/storagecommon.rng | 5 +++++
src/conf/storage_source_conf.c | 10 +++++++++
src/conf/storage_source_conf.h | 2 ++
src/qemu/qemu_command.c | 4 ++++
src/qemu/qemu_validate.c | 16 ++++++++++++++
...irtio-scsi-reservations.x86_64-latest.args | 2 +-
.../disk-virtio-scsi-reservations.xml | 2 +-
9 files changed, 63 insertions(+), 2 deletions(-)
diff --git a/docs/formatdomain.rst b/docs/formatdomain.rst
index 167912348e..9836837441 100644
--- a/docs/formatdomain.rst
+++ b/docs/formatdomain.rst
@@ -3169,6 +3169,9 @@ paravirtualized driver is specified via the ``disk`` element.
the socket, and finally ``mode`` which accepts one value ``client``
specifying the role of hypervisor. It's recommended to allow libvirt
manage the persistent reservations.
+ :since:`Since 12.1.0` the ``migration`` (values ``yes``, ``no``) controls
+ whether the hypervisor should attempt to migrate persistent reservations
+ during migration.
``initiator``
:since:`Since 4.7.0`, the ``initiator`` element is supported for
a disk ``type`` "network" that is using a ``source`` element with the
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 902c1188ef..f5c4d135a9 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -20951,6 +20951,27 @@ virDomainDiskDefCheckABIStability(virDomainDiskDef *src,
return false;
}
+ /* While not guest visible it influences the qemu migration stream so
+ * we need to keep it identical */
+ if (src->src->pr || dst->src->pr) {
+ virTristateBool srcmig = VIR_TRISTATE_BOOL_ABSENT;
+ virTristateBool dstmig = VIR_TRISTATE_BOOL_ABSENT;
+
+ if (src->src->pr)
+ srcmig = src->src->pr->migration;
+
+ if (dst->src->pr)
+ dstmig = dst->src->pr->migration;
+
+ if (srcmig != dstmig) {
+ virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+ _("Target disk reservations 'migration' property %1$s does not match source %2$s"),
+ virTristateBoolTypeToString(dstmig),
+ virTristateBoolTypeToString(srcmig));
+ return false;
+ }
+ }
+
if (!virDomainVirtioOptionsCheckABIStability(src->virtio, dst->virtio))
return false;
diff --git a/src/conf/schemas/storagecommon.rng b/src/conf/schemas/storagecommon.rng
index 14704c737e..450d53131f 100644
--- a/src/conf/schemas/storagecommon.rng
+++ b/src/conf/schemas/storagecommon.rng
@@ -104,6 +104,11 @@
<ref name="virYesNo"/>
</attribute>
</optional>
+ <optional>
+ <attribute name="migration">
+ <ref name="virYesNo"/>
+ </attribute>
+ </optional>
<optional>
<ref name="unixSocketSource"/>
</optional>
diff --git a/src/conf/storage_source_conf.c b/src/conf/storage_source_conf.c
index 087de1eaf2..24d4b0de6a 100644
--- a/src/conf/storage_source_conf.c
+++ b/src/conf/storage_source_conf.c
@@ -330,6 +330,11 @@ virStoragePRDefParseXML(xmlXPathContextPtr ctxt)
&prd->managed) < 0)
goto cleanup;
+ if (virXMLPropTristateBool(ctxt->node, "migration",
+ VIR_XML_PROP_NONZERO,
+ &prd->migration) < 0)
+ goto cleanup;
+
type = virXPathString("string(./source[1]/@type)", ctxt);
path = virXPathString("string(./source[1]/@path)", ctxt);
mode = virXPathString("string(./source[1]/@mode)", ctxt);
@@ -384,6 +389,11 @@ virStoragePRDefFormat(virBuffer *buf,
{
virBufferAsprintf(buf, "<reservations managed='%s'",
virTristateBoolTypeToString(prd->managed));
+
+ if (prd->migration != VIR_TRISTATE_BOOL_ABSENT)
+ virBufferAsprintf(buf, " migration='%s'",
+ virTristateBoolTypeToString(prd->migration));
+
if (prd->path &&
(prd->managed == VIR_TRISTATE_BOOL_NO || !migratable)) {
virBufferAddLit(buf, ">\n");
diff --git a/src/conf/storage_source_conf.h b/src/conf/storage_source_conf.h
index fc868b31af..5a4b088eeb 100644
--- a/src/conf/storage_source_conf.h
+++ b/src/conf/storage_source_conf.h
@@ -235,6 +235,8 @@ struct _virStoragePRDef {
virTristateBool managed;
char *path;
+ virTristateBool migration;
+
/* manager object alias */
char *mgralias;
};
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index f355352018..c8626e6d49 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -1691,6 +1691,7 @@ qemuBuildDiskDeviceProps(const virDomainDef *def,
g_autofree char *usbdiskalias = NULL;
const virDomainDeviceInfo *deviceinfo = &disk->info;
g_autoptr(virJSONValue) statistics = NULL;
+ virTristateBool migrate_pr = VIR_TRISTATE_BOOL_ABSENT;
virDomainDeviceInfo usbSCSIinfo = {
.type = VIR_DOMAIN_DEVICE_ADDRESS_TYPE_DRIVE,
.addr.drive = { .diskbus = VIR_DOMAIN_DISK_BUS_USB },
@@ -1716,6 +1717,8 @@ qemuBuildDiskDeviceProps(const virDomainDef *def,
case VIR_DOMAIN_DISK_BUS_SCSI:
if (disk->device == VIR_DOMAIN_DISK_DEVICE_LUN) {
driver = "scsi-block";
+ if (disk->src->pr)
+ migrate_pr = disk->src->pr->migration;
} else {
if (disk->device == VIR_DOMAIN_DISK_DEVICE_CDROM) {
driver = "scsi-cd";
@@ -1937,6 +1940,7 @@ qemuBuildDiskDeviceProps(const virDomainDef *def,
"S:rerror", rpolicy,
"A:stats-intervals", &statistics,
"T:dpofua", disk->dpofua, /* SCSI-only, ensured by validation */
+ "T:migrate-pr", migrate_pr, /* 'scsi-block' only, ensured by validation */
NULL) < 0)
return NULL;
diff --git a/src/qemu/qemu_validate.c b/src/qemu/qemu_validate.c
index da08fd17cd..a3dbd9a33b 100644
--- a/src/qemu/qemu_validate.c
+++ b/src/qemu/qemu_validate.c
@@ -3227,6 +3227,22 @@ qemuValidateDomainDeviceDefDiskFrontend(const virDomainDiskDef *disk,
}
}
+ if (disk->src->pr &&
+ disk->src->pr->migration != VIR_TRISTATE_BOOL_ABSENT) {
+ if (disk->device != VIR_DOMAIN_DISK_DEVICE_LUN ||
+ disk->bus != VIR_DOMAIN_DISK_BUS_SCSI) {
+ virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+ _("persistent reservation migration supported only with 'lun' disks on 'scsi' bus"));
+ return -1;
+ }
+
+ if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_DEVICE_SCSI_BLOCK_MIGRATE_PR)) {
+ virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+ _("persistent reservation migration not supported by this qemu"));
+ return -1;
+ }
+ }
+
if (disk->rotation_rate) {
if (disk->bus != VIR_DOMAIN_DISK_BUS_SCSI &&
disk->bus != VIR_DOMAIN_DISK_BUS_IDE &&
diff --git a/tests/qemuxmlconfdata/disk-virtio-scsi-reservations.x86_64-latest.args b/tests/qemuxmlconfdata/disk-virtio-scsi-reservations.x86_64-latest.args
index cbc2a0f398..f1d7a450ee 100644
--- a/tests/qemuxmlconfdata/disk-virtio-scsi-reservations.x86_64-latest.args
+++ b/tests/qemuxmlconfdata/disk-virtio-scsi-reservations.x86_64-latest.args
@@ -33,7 +33,7 @@ XDG_CONFIG_HOME=/var/lib/libvirt/qemu/domain--1-QEMUGuest1/.config \
-device '{"driver":"scsi-block","bus":"scsi0.0","channel":0,"scsi-id":0,"lun":0,"drive":"libvirt-2-storage","id":"scsi0-0-0-0","bootindex":1}' \
-object '{"qom-type":"pr-manager-helper","id":"pr-helper-libvirt-1-storage","path":"/path/to/qemu-pr-helper.sock"}' \
-blockdev '{"driver":"host_device","filename":"/dev/HostVG/QEMUGuest2","pr-manager":"pr-helper-libvirt-1-storage","node-name":"libvirt-1-storage","read-only":false}' \
--device '{"driver":"scsi-block","bus":"scsi0.0","channel":0,"scsi-id":0,"lun":1,"drive":"libvirt-1-storage","id":"scsi0-0-0-1"}' \
+-device '{"driver":"scsi-block","bus":"scsi0.0","channel":0,"scsi-id":0,"lun":1,"drive":"libvirt-1-storage","id":"scsi0-0-0-1","migrate-pr":true}' \
-audiodev '{"id":"audio1","driver":"none"}' \
-device '{"driver":"virtio-balloon-pci","id":"balloon0","bus":"pci.0","addr":"0x4"}' \
-sandbox on,obsolete=deny,elevateprivileges=deny,spawn=deny,resourcecontrol=deny \
diff --git a/tests/qemuxmlconfdata/disk-virtio-scsi-reservations.xml b/tests/qemuxmlconfdata/disk-virtio-scsi-reservations.xml
index 9c55d6ec3e..7f9160ff3a 100644
--- a/tests/qemuxmlconfdata/disk-virtio-scsi-reservations.xml
+++ b/tests/qemuxmlconfdata/disk-virtio-scsi-reservations.xml
@@ -28,7 +28,7 @@
<disk type='block' device='lun'>
<driver name='qemu' type='raw'/>
<source dev='/dev/HostVG/QEMUGuest2'>
- <reservations managed='no'>
+ <reservations managed='no' migration='yes'>
<source type='unix' path='/path/to/qemu-pr-helper.sock' mode='client'/>
</reservations>
</source>
--
2.53.0