On Fri, Jun 03, 2016 at 05:58:34PM +0800, Changlong Xie wrote:
> 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>
Reviewed-by: Anthony PERARD <anthony.per...@citrix.com>
Thanks,
> ---
> migration/savevm.c | 37 +++++++++++++++++++++++++++++++++++++
> qapi-schema.json | 14 ++++++++++++++
> qmp-commands.hx | 27 +++++++++++++++++++++++++++
> 3 files changed, 78 insertions(+)
>
> diff --git a/migration/savevm.c b/migration/savevm.c
> index 6c21231..ae2ef8b 100644
> --- a/migration/savevm.c
> +++ b/migration/savevm.c
> @@ -31,6 +31,7 @@
> #include "hw/boards.h"
> #include "hw/hw.h"
> #include "hw/qdev.h"
> +#include "hw/xen/xen.h"
> #include "net/net.h"
> #include "monitor/monitor.h"
> #include "sysemu/sysemu.h"
> @@ -1754,6 +1755,12 @@ 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));
>
> @@ -2064,6 +2071,36 @@ void qmp_xen_save_devices_state(const char *filename,
> Error **errp)
> }
> }
>
> +void qmp_xen_load_devices_state(const char *filename, Error **errp)
> +{
> + QEMUFile *f;
> + QIOChannelFile *ioc;
> + int ret;
> +
> + /* Guest must be paused before loading the device state; the RAM state
> + * will already have been loaded by xc
> + */
> + if (runstate_is_running()) {
> + error_setg(errp, "Cannot update device state while vm is running");
> + return;
> + }
> + vm_stop(RUN_STATE_RESTORE_VM);
> +
> + ioc = qio_channel_file_new_path(filename, O_RDONLY | O_BINARY, 0, errp);
> + if (!ioc) {
> + return;
> + }
> + f = qemu_fopen_channel_input(QIO_CHANNEL(ioc));
> +
> + migration_incoming_state_new(f);
> + ret = qemu_loadvm_state(f);
> + qemu_fclose(f);
> + if (ret < 0) {
> + error_setg(errp, QERR_IO_ERROR);
> + }
> + migration_incoming_state_destroy();
> +}
> +
> int load_vmstate(const char *name)
> {
> BlockDriverState *bs, *bs_vm_state;
> diff --git a/qapi-schema.json b/qapi-schema.json
> index 8483bdf..48c3a6f 100644
> --- a/qapi-schema.json
> +++ b/qapi-schema.json
> @@ -4201,6 +4201,20 @@
> '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'} }
> +
> +##
> # @GICCapability:
> #
> # The struct describes capability for a specific GIC (Generic
> diff --git a/qmp-commands.hx b/qmp-commands.hx
> index 28801a2..780e7f2 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
>
>
>
--
Anthony PERARD
