From: Wen Congyang <we...@cn.fujitsu.com>
Introduce a "xen-load-devices-state" QAPI command that can be used to
load the state of all devices, but not the RAM or the block devices of
the VM.
We only have hmp commands savevm/loadvm, and qmp commands
xen-save-devices-state.
We use this new command for COLO:
1. suspend both primary vm and secondary vm
2. sync the state
3. resume both primary vm and secondary vm
In such case, we need to update all devices' state in any time.
Signed-off-by: Wen Congyang <we...@cn.fujitsu.com>
Signed-off-by: Changlong Xie <xiecl.f...@cn.fujitsu.com>
---
migration/savevm.c | 36 ++++++++++++++++++++++++++++++++++++
qapi-schema.json | 14 ++++++++++++++
qmp-commands.hx | 27 +++++++++++++++++++++++++++
3 files changed, 77 insertions(+)
diff --git a/migration/savevm.c b/migration/savevm.c
index 96e7db5..aaead12 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -50,6 +50,7 @@
#include "qemu/iov.h"
#include "block/snapshot.h"
#include "block/qapi.h"
+#include "hw/xen/xen.h"
#ifndef ETH_P_RARP
@@ -1768,6 +1769,12 @@ qemu_loadvm_section_start_full(QEMUFile *f,
MigrationIncomingState *mis)
return -EINVAL;
}
+ /* Validate if it is a device's state */
+ if (xen_enabled() && se->is_ram) {
+ error_report("loadvm: %s RAM loading not allowed on Xen", idstr);
+ return -EINVAL;
+ }
+
/* Add entry */
le = g_malloc0(sizeof(*le));
@@ -2077,6 +2084,35 @@ void qmp_xen_save_devices_state(const char *filename,
Error **errp)
}
}
+void qmp_xen_load_devices_state(const char *filename, Error **errp)
+{
+ QEMUFile *f;
+ int saved_vm_running;
+ int ret;
+
+ saved_vm_running = runstate_is_running();
+ vm_stop(RUN_STATE_RESTORE_VM);
+
+ f = qemu_fopen(filename, "rb");
+ if (!f) {
+ error_setg_file_open(errp, errno, filename);
+ goto out;
+ }
+
+ migration_incoming_state_new(f);
+ ret = qemu_loadvm_state(f);
+ qemu_fclose(f);
+ migration_incoming_state_destroy();
+ if (ret < 0) {
+ error_setg(errp, QERR_IO_ERROR);
+ }
+
+out:
+ if (saved_vm_running) {
+ vm_start();
+ }
+}
+
int load_vmstate(const char *name)
{
BlockDriverState *bs, *bs_vm_state;
diff --git a/qapi-schema.json b/qapi-schema.json
index 362c9d8..8cca59d 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -4122,3 +4122,17 @@
##
{ 'enum': 'ReplayMode',
'data': [ 'none', 'record', 'play' ] }
+
+##
+# @xen-load-devices-state:
+#
+# Load the state of all devices from file. The RAM and the block devices
+# of the VM are not loaded by this command.
+#
+# @filename: the file to load the state of the devices from as binary
+# data. See xen-save-devices-state.txt for a description of the binary
+# format.
+#
+# Since: 2.7
+##
+{ 'command': 'xen-load-devices-state', 'data': {'filename': 'str'} }
diff --git a/qmp-commands.hx b/qmp-commands.hx
index b629673..4925702 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -587,6 +587,33 @@ Example:
EQMP
{
+ .name = "xen-load-devices-state",
+ .args_type = "filename:F",
+ .mhandler.cmd_new = qmp_marshal_xen_load_devices_state,
+ },
+
+SQMP
+xen-load-devices-state
+----------------------
+
+Load the state of all devices from file. The RAM and the block devices
+of the VM are not loaded by this command.
+
+Arguments:
+
+- "filename": the file to load the state of the devices from as binary
+data. See xen-save-devices-state.txt for a description of the binary
+format.
+
+Example:
+
+-> { "execute": "xen-load-devices-state",
+ "arguments": { "filename": "/tmp/resume" } }
+<- { "return": {} }
+
+EQMP
+
+ {
.name = "xen-set-global-dirty-log",
.args_type = "enable:b",
.mhandler.cmd_new = qmp_marshal_xen_set_global_dirty_log,
--
1.9.3
