migration: wire up support for snapshot device selection

Modify load_snapshot/save_snapshot to accept the device list and vmstate
node name parameters previously added to the block layer.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210204124834.774401-9-berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
This commit is contained in:
Daniel P. Berrangé 2021-02-04 12:48:30 +00:00 committed by Dr. David Alan Gilbert
parent f781f84189
commit f1a9fcdd01
6 changed files with 43 additions and 21 deletions

View File

@ -15,23 +15,37 @@
#ifndef QEMU_MIGRATION_SNAPSHOT_H
#define QEMU_MIGRATION_SNAPSHOT_H
#include "qapi/qapi-builtin-types.h"
/**
* save_snapshot: Save an internal snapshot.
* @name: name of internal snapshot
* @overwrite: replace existing snapshot with @name
* @vmstate: blockdev node name to store VM state in
* @has_devices: whether to use explicit device list
* @devices: explicit device list to snapshot
* @errp: pointer to error object
* On success, return %true.
* On failure, store an error through @errp and return %false.
*/
bool save_snapshot(const char *name, bool overwrite, Error **errp);
bool save_snapshot(const char *name, bool overwrite,
const char *vmstate,
bool has_devices, strList *devices,
Error **errp);
/**
* load_snapshot: Load an internal snapshot.
* @name: name of internal snapshot
* @vmstate: blockdev node name to load VM state from
* @has_devices: whether to use explicit device list
* @devices: explicit device list to snapshot
* @errp: pointer to error object
* On success, return %true.
* On failure, store an error through @errp and return %false.
*/
bool load_snapshot(const char *name, Error **errp);
bool load_snapshot(const char *name,
const char *vmstate,
bool has_devices, strList *devices,
Error **errp);
#endif

View File

@ -43,6 +43,8 @@
#include "qapi/error.h"
#include "qapi/qapi-commands-migration.h"
#include "qapi/qmp/json-writer.h"
#include "qapi/clone-visitor.h"
#include "qapi/qapi-builtin-visit.h"
#include "qapi/qmp/qerror.h"
#include "qemu/error-report.h"
#include "sysemu/cpus.h"
@ -2764,7 +2766,8 @@ int qemu_load_device_state(QEMUFile *f)
return 0;
}
bool save_snapshot(const char *name, bool overwrite, Error **errp)
bool save_snapshot(const char *name, bool overwrite, const char *vmstate,
bool has_devices, strList *devices, Error **errp)
{
BlockDriverState *bs;
QEMUSnapshotInfo sn1, *sn = &sn1;
@ -2786,18 +2789,19 @@ bool save_snapshot(const char *name, bool overwrite, Error **errp)
return false;
}
if (!bdrv_all_can_snapshot(false, NULL, errp)) {
if (!bdrv_all_can_snapshot(has_devices, devices, errp)) {
return false;
}
/* Delete old snapshots of the same name */
if (name) {
if (overwrite) {
if (bdrv_all_delete_snapshot(name, false, NULL, errp) < 0) {
if (bdrv_all_delete_snapshot(name, has_devices,
devices, errp) < 0) {
return false;
}
} else {
ret2 = bdrv_all_has_snapshot(name, false, NULL, errp);
ret2 = bdrv_all_has_snapshot(name, has_devices, devices, errp);
if (ret2 < 0) {
return false;
}
@ -2810,7 +2814,7 @@ bool save_snapshot(const char *name, bool overwrite, Error **errp)
}
}
bs = bdrv_all_find_vmstate_bs(NULL, false, NULL, errp);
bs = bdrv_all_find_vmstate_bs(vmstate, has_devices, devices, errp);
if (bs == NULL) {
return false;
}
@ -2875,9 +2879,10 @@ bool save_snapshot(const char *name, bool overwrite, Error **errp)
aio_context_release(aio_context);
aio_context = NULL;
ret = bdrv_all_create_snapshot(sn, bs, vm_state_size, false, NULL, errp);
ret = bdrv_all_create_snapshot(sn, bs, vm_state_size,
has_devices, devices, errp);
if (ret < 0) {
bdrv_all_delete_snapshot(sn->name, false, NULL, NULL);
bdrv_all_delete_snapshot(sn->name, has_devices, devices, NULL);
goto the_end;
}
@ -2978,7 +2983,8 @@ void qmp_xen_load_devices_state(const char *filename, Error **errp)
migration_incoming_state_destroy();
}
bool load_snapshot(const char *name, Error **errp)
bool load_snapshot(const char *name, const char *vmstate,
bool has_devices, strList *devices, Error **errp)
{
BlockDriverState *bs_vm_state;
QEMUSnapshotInfo sn;
@ -2987,10 +2993,10 @@ bool load_snapshot(const char *name, Error **errp)
AioContext *aio_context;
MigrationIncomingState *mis = migration_incoming_get_current();
if (!bdrv_all_can_snapshot(false, NULL, errp)) {
if (!bdrv_all_can_snapshot(has_devices, devices, errp)) {
return false;
}
ret = bdrv_all_has_snapshot(name, false, NULL, errp);
ret = bdrv_all_has_snapshot(name, has_devices, devices, errp);
if (ret < 0) {
return false;
}
@ -3000,7 +3006,7 @@ bool load_snapshot(const char *name, Error **errp)
return false;
}
bs_vm_state = bdrv_all_find_vmstate_bs(NULL, false, NULL, errp);
bs_vm_state = bdrv_all_find_vmstate_bs(vmstate, has_devices, devices, errp);
if (!bs_vm_state) {
return false;
}
@ -3027,7 +3033,7 @@ bool load_snapshot(const char *name, Error **errp)
/* Flush all IO requests so they don't interfere with the new state. */
bdrv_drain_all_begin();
ret = bdrv_all_goto_snapshot(name, false, NULL, errp);
ret = bdrv_all_goto_snapshot(name, has_devices, devices, errp);
if (ret < 0) {
goto err_drain;
}

View File

@ -1139,7 +1139,7 @@ void hmp_loadvm(Monitor *mon, const QDict *qdict)
vm_stop(RUN_STATE_RESTORE_VM);
if (!load_snapshot(name, &err) && saved_vm_running) {
if (!load_snapshot(name, NULL, false, NULL, &err) && saved_vm_running) {
vm_start();
}
hmp_handle_error(mon, err);
@ -1149,7 +1149,8 @@ void hmp_savevm(Monitor *mon, const QDict *qdict)
{
Error *err = NULL;
save_snapshot(qdict_get_try_str(qdict, "name"), true, &err);
save_snapshot(qdict_get_try_str(qdict, "name"),
true, NULL, false, NULL, &err);
hmp_handle_error(mon, err);
}

View File

@ -196,7 +196,7 @@ static void replay_seek(int64_t icount, QEMUTimerCB callback, Error **errp)
if (icount < replay_get_current_icount()
|| replay_get_current_icount() < snapshot_icount) {
vm_stop(RUN_STATE_RESTORE_VM);
load_snapshot(snapshot, errp);
load_snapshot(snapshot, NULL, false, NULL, errp);
}
g_free(snapshot);
}
@ -327,7 +327,7 @@ void replay_gdb_attached(void)
*/
if (replay_mode == REPLAY_MODE_PLAY
&& !replay_snapshot) {
if (!save_snapshot("start_debugging", true, NULL)) {
if (!save_snapshot("start_debugging", true, NULL, false, NULL, NULL)) {
/* Can't create the snapshot. Continue conventional debugging. */
}
}

View File

@ -77,13 +77,14 @@ void replay_vmstate_init(void)
if (replay_snapshot) {
if (replay_mode == REPLAY_MODE_RECORD) {
if (!save_snapshot(replay_snapshot, true, &err)) {
if (!save_snapshot(replay_snapshot,
true, NULL, false, NULL, &err)) {
error_report_err(err);
error_report("Could not create snapshot for icount record");
exit(1);
}
} else if (replay_mode == REPLAY_MODE_PLAY) {
if (!load_snapshot(replay_snapshot, &err)) {
if (!load_snapshot(replay_snapshot, NULL, false, NULL, &err)) {
error_report_err(err);
error_report("Could not load snapshot for icount replay");
exit(1);

View File

@ -2530,7 +2530,7 @@ void qmp_x_exit_preconfig(Error **errp)
if (loadvm) {
Error *local_err = NULL;
if (!load_snapshot(loadvm, &local_err)) {
if (!load_snapshot(loadvm, NULL, false, NULL, &local_err)) {
error_report_err(local_err);
autostart = 0;
exit(1);