/*
* qemu_snapshot.c: snapshot related implementation
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see
* .
*/
#include
#include "qemu_snapshot.h"
#include "qemu_monitor.h"
#include "qemu_domain.h"
#include "qemu_block.h"
#include "qemu_process.h"
#include "qemu_migration.h"
#include "qemu_command.h"
#include "qemu_security.h"
#include "qemu_saveimage.h"
#include "virerror.h"
#include "virlog.h"
#include "datatypes.h"
#include "viralloc.h"
#include "domain_conf.h"
#include "domain_audit.h"
#include "locking/domain_lock.h"
#include "libvirt_internal.h"
#include "virxml.h"
#include "virstoragefile.h"
#include "virstring.h"
#include "virdomainsnapshotobjlist.h"
#include "virqemu.h"
#include "storage_source.h"
#define VIR_FROM_THIS VIR_FROM_QEMU
VIR_LOG_INIT("qemu.qemu_snapshot");
/**
* qemuSnapshotSetCurrent: Set currently active snapshot
*
* @vm: domain object
* @newcurrent: snapshot object to set as current/active
*
* Sets @newcurrent as the 'current' snapshot of @vm. This helper ensures that
* the snapshot which was 'current' previously is updated.
*/
static void
qemuSnapshotSetCurrent(virDomainObjPtr vm,
virDomainMomentObjPtr newcurrent)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
virQEMUDriverPtr driver = priv->driver;
g_autoptr(virQEMUDriverConfig) cfg = virQEMUDriverGetConfig(driver);
virDomainMomentObjPtr oldcurrent = virDomainSnapshotGetCurrent(vm->snapshots);
virDomainSnapshotSetCurrent(vm->snapshots, newcurrent);
/* we need to write out metadata for the old snapshot to update the
* 'active' property */
if (oldcurrent &&
oldcurrent != newcurrent) {
if (qemuDomainSnapshotWriteMetadata(vm, oldcurrent, driver->xmlopt, cfg->snapshotDir) < 0)
VIR_WARN("failed to update old current snapshot");
}
}
/* Looks up snapshot object from VM and name */
virDomainMomentObjPtr
qemuSnapObjFromName(virDomainObjPtr vm,
const char *name)
{
virDomainMomentObjPtr snap = NULL;
snap = virDomainSnapshotFindByName(vm->snapshots, name);
if (!snap)
virReportError(VIR_ERR_NO_DOMAIN_SNAPSHOT,
_("no domain snapshot with matching name '%s'"),
name);
return snap;
}
/* Looks up snapshot object from VM and snapshotPtr */
virDomainMomentObjPtr
qemuSnapObjFromSnapshot(virDomainObjPtr vm,
virDomainSnapshotPtr snapshot)
{
return qemuSnapObjFromName(vm, snapshot->name);
}
/* Count how many snapshots in a set are external snapshots. */
static int
qemuSnapshotCountExternal(void *payload,
const char *name G_GNUC_UNUSED,
void *data)
{
virDomainMomentObjPtr snap = payload;
int *count = data;
if (virDomainSnapshotIsExternal(snap))
(*count)++;
return 0;
}
int
qemuSnapshotFSFreeze(virDomainObjPtr vm,
const char **mountpoints,
unsigned int nmountpoints)
{
qemuAgentPtr agent;
int frozen;
if (!qemuDomainAgentAvailable(vm, true))
return -1;
agent = qemuDomainObjEnterAgent(vm);
frozen = qemuAgentFSFreeze(agent, mountpoints, nmountpoints);
qemuDomainObjExitAgent(vm, agent);
return frozen;
}
/* Return -1 on error, otherwise number of thawed filesystems. */
int
qemuSnapshotFSThaw(virDomainObjPtr vm,
bool report)
{
qemuAgentPtr agent;
int thawed;
virErrorPtr err = NULL;
if (!qemuDomainAgentAvailable(vm, report))
return -1;
agent = qemuDomainObjEnterAgent(vm);
if (!report)
virErrorPreserveLast(&err);
thawed = qemuAgentFSThaw(agent);
qemuDomainObjExitAgent(vm, agent);
virErrorRestore(&err);
return thawed;
}
/* The domain is expected to be locked and inactive. */
static int
qemuSnapshotCreateInactiveInternal(virQEMUDriverPtr driver,
virDomainObjPtr vm,
virDomainMomentObjPtr snap)
{
return qemuDomainSnapshotForEachQcow2(driver, vm->def, snap, "-c", false);
}
/* The domain is expected to be locked and inactive. */
static int
qemuSnapshotCreateInactiveExternal(virQEMUDriverPtr driver,
virDomainObjPtr vm,
virDomainMomentObjPtr snap,
bool reuse)
{
size_t i;
virDomainSnapshotDiskDefPtr snapdisk;
virDomainDiskDefPtr defdisk;
virCommandPtr cmd = NULL;
const char *qemuImgPath;
virBitmapPtr created = NULL;
g_autoptr(virQEMUDriverConfig) cfg = virQEMUDriverGetConfig(driver);
int ret = -1;
g_auto(virBuffer) buf = VIR_BUFFER_INITIALIZER;
virDomainSnapshotDefPtr snapdef = virDomainSnapshotObjGetDef(snap);
if (!(qemuImgPath = qemuFindQemuImgBinary(driver)))
goto cleanup;
created = virBitmapNew(snapdef->ndisks);
/* If reuse is true, then qemuSnapshotPrepare already
* ensured that the new files exist, and it was up to the user to
* create them correctly. */
for (i = 0; i < snapdef->ndisks && !reuse; i++) {
snapdisk = &(snapdef->disks[i]);
defdisk = vm->def->disks[i];
if (snapdisk->snapshot != VIR_DOMAIN_SNAPSHOT_LOCATION_EXTERNAL)
continue;
if (!snapdisk->src->format)
snapdisk->src->format = VIR_STORAGE_FILE_QCOW2;
if (qemuDomainStorageSourceValidateDepth(defdisk->src, 1, defdisk->dst) < 0)
goto cleanup;
/* creates cmd line args: qemu-img create -f qcow2 -o */
if (!(cmd = virCommandNewArgList(qemuImgPath,
"create",
"-f",
virStorageFileFormatTypeToString(snapdisk->src->format),
"-o",
NULL)))
goto cleanup;
/* adds cmd line arg: backing_fmt=format,backing_file=/path/to/backing/file */
virBufferAsprintf(&buf, "backing_fmt=%s,backing_file=",
virStorageFileFormatTypeToString(defdisk->src->format));
virQEMUBuildBufferEscapeComma(&buf, defdisk->src->path);
virCommandAddArgBuffer(cmd, &buf);
/* adds cmd line args: /path/to/target/file */
virQEMUBuildBufferEscapeComma(&buf, snapdisk->src->path);
virCommandAddArgBuffer(cmd, &buf);
/* If the target does not exist, we're going to create it possibly */
if (!virFileExists(snapdisk->src->path))
ignore_value(virBitmapSetBit(created, i));
if (virCommandRun(cmd, NULL) < 0)
goto cleanup;
virCommandFree(cmd);
cmd = NULL;
}
/* update disk definitions */
for (i = 0; i < snapdef->ndisks; i++) {
g_autoptr(virStorageSource) newsrc = NULL;
snapdisk = &(snapdef->disks[i]);
defdisk = vm->def->disks[i];
if (snapdisk->snapshot != VIR_DOMAIN_SNAPSHOT_LOCATION_EXTERNAL)
continue;
if (!(newsrc = virStorageSourceCopy(snapdisk->src, false)))
goto cleanup;
if (virStorageSourceInitChainElement(newsrc, defdisk->src, false) < 0)
goto cleanup;
if (!reuse &&
virStorageSourceHasBacking(defdisk->src)) {
defdisk->src->readonly = true;
newsrc->backingStore = g_steal_pointer(&defdisk->src);
} else {
virObjectUnref(defdisk->src);
}
defdisk->src = g_steal_pointer(&newsrc);
}
if (virDomainDefSave(vm->def, driver->xmlopt, cfg->configDir) < 0)
goto cleanup;
ret = 0;
cleanup:
virCommandFree(cmd);
/* unlink images if creation has failed */
if (ret < 0 && created) {
ssize_t bit = -1;
while ((bit = virBitmapNextSetBit(created, bit)) >= 0) {
snapdisk = &(snapdef->disks[bit]);
if (unlink(snapdisk->src->path) < 0)
VIR_WARN("Failed to remove snapshot image '%s'",
snapdisk->src->path);
}
}
virBitmapFree(created);
return ret;
}
/* The domain is expected to be locked and active. */
static int
qemuSnapshotCreateActiveInternal(virQEMUDriverPtr driver,
virDomainObjPtr vm,
virDomainMomentObjPtr snap,
unsigned int flags)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
virObjectEventPtr event = NULL;
bool resume = false;
virDomainSnapshotDefPtr snapdef = virDomainSnapshotObjGetDef(snap);
int ret = -1;
if (!qemuMigrationSrcIsAllowed(driver, vm, false, 0))
goto cleanup;
if (virDomainObjGetState(vm, NULL) == VIR_DOMAIN_RUNNING) {
/* savevm monitor command pauses the domain emitting an event which
* confuses libvirt since it's not notified when qemu resumes the
* domain. Thus we stop and start CPUs ourselves.
*/
if (qemuProcessStopCPUs(driver, vm, VIR_DOMAIN_PAUSED_SAVE,
QEMU_ASYNC_JOB_SNAPSHOT) < 0)
goto cleanup;
resume = true;
if (!virDomainObjIsActive(vm)) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("guest unexpectedly quit"));
goto cleanup;
}
}
if (qemuDomainObjEnterMonitorAsync(driver, vm,
QEMU_ASYNC_JOB_SNAPSHOT) < 0) {
resume = false;
goto cleanup;
}
ret = qemuMonitorCreateSnapshot(priv->mon, snap->def->name);
if (qemuDomainObjExitMonitor(driver, vm) < 0)
ret = -1;
if (ret < 0)
goto cleanup;
if (!(snapdef->cookie = (virObjectPtr) qemuDomainSaveCookieNew(vm)))
goto cleanup;
if (flags & VIR_DOMAIN_SNAPSHOT_CREATE_HALT) {
event = virDomainEventLifecycleNewFromObj(vm, VIR_DOMAIN_EVENT_STOPPED,
VIR_DOMAIN_EVENT_STOPPED_FROM_SNAPSHOT);
qemuProcessStop(driver, vm, VIR_DOMAIN_SHUTOFF_FROM_SNAPSHOT,
QEMU_ASYNC_JOB_SNAPSHOT, 0);
virDomainAuditStop(vm, "from-snapshot");
resume = false;
}
cleanup:
if (resume && virDomainObjIsActive(vm) &&
qemuProcessStartCPUs(driver, vm,
VIR_DOMAIN_RUNNING_UNPAUSED,
QEMU_ASYNC_JOB_SNAPSHOT) < 0) {
event = virDomainEventLifecycleNewFromObj(vm,
VIR_DOMAIN_EVENT_SUSPENDED,
VIR_DOMAIN_EVENT_SUSPENDED_API_ERROR);
if (virGetLastErrorCode() == VIR_ERR_OK) {
virReportError(VIR_ERR_OPERATION_FAILED, "%s",
_("resuming after snapshot failed"));
}
}
virObjectEventStateQueue(driver->domainEventState, event);
return ret;
}
static int
qemuSnapshotPrepareDiskShared(virDomainSnapshotDiskDefPtr snapdisk,
virDomainDiskDefPtr domdisk)
{
if (!domdisk->src->shared || domdisk->src->readonly)
return 0;
if (!qemuBlockStorageSourceSupportsConcurrentAccess(snapdisk->src)) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
_("shared access for disk '%s' requires use of "
"supported storage format"), domdisk->dst);
return -1;
}
return 0;
}
static int
qemuSnapshotPrepareDiskExternalInactive(virDomainSnapshotDiskDefPtr snapdisk,
virDomainDiskDefPtr domdisk)
{
int domDiskType = virStorageSourceGetActualType(domdisk->src);
int snapDiskType = virStorageSourceGetActualType(snapdisk->src);
switch ((virStorageType)domDiskType) {
case VIR_STORAGE_TYPE_BLOCK:
case VIR_STORAGE_TYPE_FILE:
break;
case VIR_STORAGE_TYPE_NETWORK:
switch ((virStorageNetProtocol) domdisk->src->protocol) {
case VIR_STORAGE_NET_PROTOCOL_NONE:
case VIR_STORAGE_NET_PROTOCOL_NBD:
case VIR_STORAGE_NET_PROTOCOL_RBD:
case VIR_STORAGE_NET_PROTOCOL_SHEEPDOG:
case VIR_STORAGE_NET_PROTOCOL_GLUSTER:
case VIR_STORAGE_NET_PROTOCOL_ISCSI:
case VIR_STORAGE_NET_PROTOCOL_HTTP:
case VIR_STORAGE_NET_PROTOCOL_HTTPS:
case VIR_STORAGE_NET_PROTOCOL_FTP:
case VIR_STORAGE_NET_PROTOCOL_FTPS:
case VIR_STORAGE_NET_PROTOCOL_TFTP:
case VIR_STORAGE_NET_PROTOCOL_SSH:
case VIR_STORAGE_NET_PROTOCOL_VXHS:
case VIR_STORAGE_NET_PROTOCOL_NFS:
case VIR_STORAGE_NET_PROTOCOL_LAST:
virReportError(VIR_ERR_INTERNAL_ERROR,
_("external inactive snapshots are not supported on "
"'network' disks using '%s' protocol"),
virStorageNetProtocolTypeToString(domdisk->src->protocol));
return -1;
}
break;
case VIR_STORAGE_TYPE_DIR:
case VIR_STORAGE_TYPE_VOLUME:
case VIR_STORAGE_TYPE_NVME:
case VIR_STORAGE_TYPE_VHOST_USER:
case VIR_STORAGE_TYPE_NONE:
case VIR_STORAGE_TYPE_LAST:
virReportError(VIR_ERR_INTERNAL_ERROR,
_("external inactive snapshots are not supported on "
"'%s' disks"), virStorageTypeToString(domDiskType));
return -1;
}
switch ((virStorageType)snapDiskType) {
case VIR_STORAGE_TYPE_BLOCK:
case VIR_STORAGE_TYPE_FILE:
break;
case VIR_STORAGE_TYPE_NETWORK:
case VIR_STORAGE_TYPE_DIR:
case VIR_STORAGE_TYPE_VOLUME:
case VIR_STORAGE_TYPE_NVME:
case VIR_STORAGE_TYPE_VHOST_USER:
case VIR_STORAGE_TYPE_NONE:
case VIR_STORAGE_TYPE_LAST:
virReportError(VIR_ERR_INTERNAL_ERROR,
_("external inactive snapshots are not supported on "
"'%s' disks"), virStorageTypeToString(snapDiskType));
return -1;
}
if (qemuSnapshotPrepareDiskShared(snapdisk, domdisk) < 0)
return -1;
return 0;
}
static int
qemuSnapshotPrepareDiskExternalActive(virDomainObjPtr vm,
virDomainSnapshotDiskDefPtr snapdisk,
virDomainDiskDefPtr domdisk,
bool blockdev)
{
int actualType = virStorageSourceGetActualType(snapdisk->src);
if (domdisk->device == VIR_DOMAIN_DISK_DEVICE_LUN) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("external active snapshots are not supported on scsi "
"passthrough devices"));
return -1;
}
if (!qemuDomainDiskBlockJobIsSupported(vm, domdisk))
return -1;
switch ((virStorageType)actualType) {
case VIR_STORAGE_TYPE_BLOCK:
case VIR_STORAGE_TYPE_FILE:
break;
case VIR_STORAGE_TYPE_NETWORK:
/* defer all of the checking to either qemu or libvirt's blockdev code */
if (blockdev)
break;
switch ((virStorageNetProtocol) snapdisk->src->protocol) {
case VIR_STORAGE_NET_PROTOCOL_GLUSTER:
break;
case VIR_STORAGE_NET_PROTOCOL_NONE:
case VIR_STORAGE_NET_PROTOCOL_NBD:
case VIR_STORAGE_NET_PROTOCOL_RBD:
case VIR_STORAGE_NET_PROTOCOL_SHEEPDOG:
case VIR_STORAGE_NET_PROTOCOL_ISCSI:
case VIR_STORAGE_NET_PROTOCOL_HTTP:
case VIR_STORAGE_NET_PROTOCOL_HTTPS:
case VIR_STORAGE_NET_PROTOCOL_FTP:
case VIR_STORAGE_NET_PROTOCOL_FTPS:
case VIR_STORAGE_NET_PROTOCOL_TFTP:
case VIR_STORAGE_NET_PROTOCOL_SSH:
case VIR_STORAGE_NET_PROTOCOL_VXHS:
case VIR_STORAGE_NET_PROTOCOL_NFS:
case VIR_STORAGE_NET_PROTOCOL_LAST:
virReportError(VIR_ERR_INTERNAL_ERROR,
_("external active snapshots are not supported on "
"'network' disks using '%s' protocol"),
virStorageNetProtocolTypeToString(snapdisk->src->protocol));
return -1;
}
break;
case VIR_STORAGE_TYPE_DIR:
case VIR_STORAGE_TYPE_VOLUME:
case VIR_STORAGE_TYPE_NVME:
case VIR_STORAGE_TYPE_VHOST_USER:
case VIR_STORAGE_TYPE_NONE:
case VIR_STORAGE_TYPE_LAST:
virReportError(VIR_ERR_INTERNAL_ERROR,
_("external active snapshots are not supported on "
"'%s' disks"), virStorageTypeToString(actualType));
return -1;
}
if (qemuSnapshotPrepareDiskShared(snapdisk, domdisk) < 0)
return -1;
return 0;
}
static int
qemuSnapshotPrepareDiskExternal(virDomainObjPtr vm,
virDomainDiskDefPtr disk,
virDomainSnapshotDiskDefPtr snapdisk,
bool active,
bool reuse,
bool blockdev)
{
struct stat st;
int err;
int rc;
if (disk->src->readonly && !(reuse || blockdev)) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
_("external snapshot for readonly disk %s "
"is not supported"), disk->dst);
return -1;
}
if (qemuTranslateSnapshotDiskSourcePool(snapdisk) < 0)
return -1;
if (!active) {
if (virDomainDiskTranslateSourcePool(disk) < 0)
return -1;
if (qemuSnapshotPrepareDiskExternalInactive(snapdisk, disk) < 0)
return -1;
} else {
if (qemuSnapshotPrepareDiskExternalActive(vm, snapdisk, disk, blockdev) < 0)
return -1;
}
if (virStorageSourceIsLocalStorage(snapdisk->src)) {
if (virStorageSourceInit(snapdisk->src) < 0)
return -1;
rc = virStorageSourceStat(snapdisk->src, &st);
err = errno;
virStorageSourceDeinit(snapdisk->src);
if (rc < 0) {
if (err != ENOENT) {
virReportSystemError(err,
_("unable to stat for disk %s: %s"),
snapdisk->name, snapdisk->src->path);
return -1;
} else if (reuse) {
virReportSystemError(err,
_("missing existing file for disk %s: %s"),
snapdisk->name, snapdisk->src->path);
return -1;
}
} else if (!S_ISBLK(st.st_mode) && st.st_size && !reuse) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
_("external snapshot file for disk %s already "
"exists and is not a block device: %s"),
snapdisk->name, snapdisk->src->path);
return -1;
}
}
return 0;
}
static int
qemuSnapshotPrepareDiskInternal(virDomainDiskDefPtr disk,
bool active)
{
int actualType;
/* active disks are handled by qemu itself so no need to worry about those */
if (active)
return 0;
if (virDomainDiskTranslateSourcePool(disk) < 0)
return -1;
actualType = virStorageSourceGetActualType(disk->src);
switch ((virStorageType)actualType) {
case VIR_STORAGE_TYPE_BLOCK:
case VIR_STORAGE_TYPE_FILE:
return 0;
case VIR_STORAGE_TYPE_NETWORK:
switch ((virStorageNetProtocol) disk->src->protocol) {
case VIR_STORAGE_NET_PROTOCOL_NONE:
case VIR_STORAGE_NET_PROTOCOL_NBD:
case VIR_STORAGE_NET_PROTOCOL_RBD:
case VIR_STORAGE_NET_PROTOCOL_SHEEPDOG:
case VIR_STORAGE_NET_PROTOCOL_GLUSTER:
case VIR_STORAGE_NET_PROTOCOL_ISCSI:
case VIR_STORAGE_NET_PROTOCOL_HTTP:
case VIR_STORAGE_NET_PROTOCOL_HTTPS:
case VIR_STORAGE_NET_PROTOCOL_FTP:
case VIR_STORAGE_NET_PROTOCOL_FTPS:
case VIR_STORAGE_NET_PROTOCOL_TFTP:
case VIR_STORAGE_NET_PROTOCOL_SSH:
case VIR_STORAGE_NET_PROTOCOL_VXHS:
case VIR_STORAGE_NET_PROTOCOL_NFS:
case VIR_STORAGE_NET_PROTOCOL_LAST:
virReportError(VIR_ERR_INTERNAL_ERROR,
_("internal inactive snapshots are not supported on "
"'network' disks using '%s' protocol"),
virStorageNetProtocolTypeToString(disk->src->protocol));
return -1;
}
break;
case VIR_STORAGE_TYPE_DIR:
case VIR_STORAGE_TYPE_VOLUME:
case VIR_STORAGE_TYPE_NVME:
case VIR_STORAGE_TYPE_VHOST_USER:
case VIR_STORAGE_TYPE_NONE:
case VIR_STORAGE_TYPE_LAST:
virReportError(VIR_ERR_INTERNAL_ERROR,
_("internal inactive snapshots are not supported on "
"'%s' disks"), virStorageTypeToString(actualType));
return -1;
}
return 0;
}
static int
qemuSnapshotPrepare(virDomainObjPtr vm,
virDomainSnapshotDefPtr def,
unsigned int *flags)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
bool blockdev = virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_BLOCKDEV);
size_t i;
bool active = virDomainObjIsActive(vm);
bool reuse = (*flags & VIR_DOMAIN_SNAPSHOT_CREATE_REUSE_EXT) != 0;
bool found_internal = false;
bool forbid_internal = false;
int external = 0;
for (i = 0; i < def->ndisks; i++) {
virDomainSnapshotDiskDefPtr disk = &def->disks[i];
virDomainDiskDefPtr dom_disk = vm->def->disks[i];
if (disk->snapshot != VIR_DOMAIN_SNAPSHOT_LOCATION_NONE &&
qemuDomainDiskBlockJobIsActive(dom_disk))
return -1;
switch ((virDomainSnapshotLocation) disk->snapshot) {
case VIR_DOMAIN_SNAPSHOT_LOCATION_INTERNAL:
found_internal = true;
if (def->state == VIR_DOMAIN_SNAPSHOT_DISK_SNAPSHOT && active) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
_("active qemu domains require external disk "
"snapshots; disk %s requested internal"),
disk->name);
return -1;
}
if (qemuSnapshotPrepareDiskInternal(dom_disk,
active) < 0)
return -1;
if (dom_disk->src->format > 0 &&
dom_disk->src->format != VIR_STORAGE_FILE_QCOW2) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
_("internal snapshot for disk %s unsupported "
"for storage type %s"),
disk->name,
virStorageFileFormatTypeToString(dom_disk->src->format));
return -1;
}
break;
case VIR_DOMAIN_SNAPSHOT_LOCATION_EXTERNAL:
if (!disk->src->format) {
disk->src->format = VIR_STORAGE_FILE_QCOW2;
} else if (disk->src->format != VIR_STORAGE_FILE_QCOW2 &&
disk->src->format != VIR_STORAGE_FILE_QED) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
_("external snapshot format for disk %s "
"is unsupported: %s"),
disk->name,
virStorageFileFormatTypeToString(disk->src->format));
return -1;
}
if (disk->src->metadataCacheMaxSize > 0) {
if (disk->src->format != VIR_STORAGE_FILE_QCOW2) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("metdata cache max size control is supported only with qcow2 images"));
return -1;
}
if (!blockdev) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("metdata cache max size control is not supported with this QEMU binary"));
return -1;
}
}
if (qemuSnapshotPrepareDiskExternal(vm, dom_disk, disk,
active, reuse, blockdev) < 0)
return -1;
external++;
break;
case VIR_DOMAIN_SNAPSHOT_LOCATION_NONE:
/* Remember seeing a disk that has snapshot disabled */
if (!virStorageSourceIsEmpty(dom_disk->src) &&
!dom_disk->src->readonly)
forbid_internal = true;
break;
case VIR_DOMAIN_SNAPSHOT_LOCATION_DEFAULT:
case VIR_DOMAIN_SNAPSHOT_LOCATION_LAST:
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("unexpected code path"));
return -1;
}
}
if (!found_internal && !external &&
def->memory == VIR_DOMAIN_SNAPSHOT_LOCATION_NONE) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("nothing selected for snapshot"));
return -1;
}
/* internal snapshot requires a disk image to store the memory image to, and
* also disks can't be excluded from an internal snapshot */
if ((def->memory == VIR_DOMAIN_SNAPSHOT_LOCATION_INTERNAL && !found_internal) ||
(found_internal && forbid_internal)) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("internal and full system snapshots require all "
"disks to be selected for snapshot"));
return -1;
}
/* disk snapshot requires at least one disk */
if (def->state == VIR_DOMAIN_SNAPSHOT_DISK_SNAPSHOT && !external) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("disk-only snapshots require at least "
"one disk to be selected for snapshot"));
return -1;
}
/* For now, we don't allow mixing internal and external disks.
* XXX technically, we could mix internal and external disks for
* offline snapshots */
if ((found_internal && external) ||
(def->memory == VIR_DOMAIN_SNAPSHOT_LOCATION_INTERNAL && external) ||
(def->memory == VIR_DOMAIN_SNAPSHOT_LOCATION_EXTERNAL && found_internal)) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("mixing internal and external targets for a snapshot "
"is not yet supported"));
return -1;
}
/* internal snapshots + pflash based loader have the following problems:
* - if the variable store is raw, the snapshot fails
* - allowing a qcow2 image as the varstore would make it eligible to receive
* the vmstate dump, which would make it huge
* - offline snapshot would not snapshot the varstore at all
*
* Avoid the issues by forbidding internal snapshot with pflash completely.
*/
if (found_internal &&
virDomainDefHasOldStyleUEFI(vm->def)) {
virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s",
_("internal snapshots of a VM with pflash based "
"firmware are not supported"));
return -1;
}
/* Alter flags to let later users know what we learned. */
if (external && !active)
*flags |= VIR_DOMAIN_SNAPSHOT_CREATE_DISK_ONLY;
return 0;
}
struct _qemuSnapshotDiskData {
virStorageSourcePtr src;
bool initialized; /* @src was initialized in the storage driver */
bool created; /* @src was created by the snapshot code */
bool prepared; /* @src was prepared using qemuDomainStorageSourceAccessAllow */
virDomainDiskDefPtr disk;
char *relPath; /* relative path component to fill into original disk */
qemuBlockStorageSourceChainDataPtr crdata;
bool blockdevadded;
virStorageSourcePtr persistsrc;
virDomainDiskDefPtr persistdisk;
};
typedef struct _qemuSnapshotDiskData qemuSnapshotDiskData;
typedef qemuSnapshotDiskData *qemuSnapshotDiskDataPtr;
static void
qemuSnapshotDiskCleanup(qemuSnapshotDiskDataPtr data,
size_t ndata,
virDomainObjPtr vm,
qemuDomainAsyncJob asyncJob)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
virQEMUDriverPtr driver = priv->driver;
virErrorPtr orig_err;
size_t i;
if (!data)
return;
virErrorPreserveLast(&orig_err);
for (i = 0; i < ndata; i++) {
/* on success of the snapshot the 'src' and 'persistsrc' properties will
* be set to NULL by qemuSnapshotDiskUpdateSource */
if (data[i].src) {
if (data[i].blockdevadded) {
if (qemuDomainObjEnterMonitorAsync(driver, vm, asyncJob) == 0) {
qemuBlockStorageSourceAttachRollback(qemuDomainGetMonitor(vm),
data[i].crdata->srcdata[0]);
ignore_value(qemuDomainObjExitMonitor(driver, vm));
}
}
if (data[i].created &&
virStorageSourceUnlink(data[i].src) < 0) {
VIR_WARN("Unable to remove just-created %s",
NULLSTR(data[i].src->path));
}
if (data[i].initialized)
virStorageSourceDeinit(data[i].src);
if (data[i].prepared)
qemuDomainStorageSourceAccessRevoke(driver, vm, data[i].src);
virObjectUnref(data[i].src);
}
virObjectUnref(data[i].persistsrc);
VIR_FREE(data[i].relPath);
qemuBlockStorageSourceChainDataFree(data[i].crdata);
}
VIR_FREE(data);
virErrorRestore(&orig_err);
}
struct _qemuSnapshotDiskContext {
qemuSnapshotDiskDataPtr dd;
size_t ndd;
virJSONValuePtr actions;
/* needed for automatic cleanup of 'dd' */
virDomainObjPtr vm;
qemuDomainAsyncJob asyncJob;
};
typedef struct _qemuSnapshotDiskContext qemuSnapshotDiskContext;
typedef qemuSnapshotDiskContext *qemuSnapshotDiskContextPtr;
static qemuSnapshotDiskContextPtr
qemuSnapshotDiskContextNew(size_t ndisks,
virDomainObjPtr vm,
qemuDomainAsyncJob asyncJob)
{
qemuSnapshotDiskContextPtr ret = g_new0(qemuSnapshotDiskContext, 1);
ret->dd = g_new0(qemuSnapshotDiskData, ndisks);
ret->actions = virJSONValueNewArray();
ret->vm = vm;
ret->asyncJob = asyncJob;
return ret;
}
static void
qemuSnapshotDiskContextCleanup(qemuSnapshotDiskContextPtr snapctxt)
{
if (!snapctxt)
return;
virJSONValueFree(snapctxt->actions);
qemuSnapshotDiskCleanup(snapctxt->dd, snapctxt->ndd, snapctxt->vm, snapctxt->asyncJob);
g_free(snapctxt);
}
G_DEFINE_AUTOPTR_CLEANUP_FUNC(qemuSnapshotDiskContext, qemuSnapshotDiskContextCleanup);
/**
* qemuSnapshotDiskBitmapsPropagate:
*
* This function propagates any active persistent bitmap present in the original
* image into the new snapshot. This is necessary to keep tracking the changed
* blocks in the active bitmaps as the backing file will become read-only.
* We leave the original bitmap active as in cases when the overlay is
* discarded (snapshot revert with abandoning the history) everything works as
* expected.
*/
static int
qemuSnapshotDiskBitmapsPropagate(qemuSnapshotDiskDataPtr dd,
virJSONValuePtr actions,
GHashTable *blockNamedNodeData)
{
qemuBlockNamedNodeDataPtr entry;
size_t i;
if (!(entry = virHashLookup(blockNamedNodeData, dd->disk->src->nodeformat)))
return 0;
for (i = 0; i < entry->nbitmaps; i++) {
qemuBlockNamedNodeDataBitmapPtr bitmap = entry->bitmaps[i];
/* we don't care about temporary, inconsistent, or disabled bitmaps */
if (!bitmap->persistent || !bitmap->recording || bitmap->inconsistent)
continue;
if (qemuMonitorTransactionBitmapAdd(actions, dd->src->nodeformat,
bitmap->name, true, false,
bitmap->granularity) < 0)
return -1;
}
return 0;
}
static int
qemuSnapshotDiskPrepareOneBlockdev(virQEMUDriverPtr driver,
virDomainObjPtr vm,
qemuSnapshotDiskDataPtr dd,
virQEMUDriverConfigPtr cfg,
bool reuse,
GHashTable *blockNamedNodeData,
qemuDomainAsyncJob asyncJob)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
g_autoptr(virStorageSource) terminator = NULL;
int rc;
/* create a terminator for the snapshot disks so that qemu does not try
* to open them at first */
terminator = virStorageSourceNew();
if (qemuDomainPrepareStorageSourceBlockdev(dd->disk, dd->src,
priv, cfg) < 0)
return -1;
if (!(dd->crdata = qemuBuildStorageSourceChainAttachPrepareBlockdevTop(dd->src,
terminator,
priv->qemuCaps)))
return -1;
if (reuse) {
if (qemuDomainObjEnterMonitorAsync(driver, vm, asyncJob) < 0)
return -1;
rc = qemuBlockStorageSourceAttachApply(qemuDomainGetMonitor(vm),
dd->crdata->srcdata[0]);
if (qemuDomainObjExitMonitor(driver, vm) < 0 || rc < 0)
return -1;
} else {
if (qemuBlockStorageSourceCreateDetectSize(blockNamedNodeData,
dd->src, dd->disk->src) < 0)
return -1;
if (qemuBlockStorageSourceCreate(vm, dd->src, dd->disk->src,
NULL, dd->crdata->srcdata[0],
asyncJob) < 0)
return -1;
}
dd->blockdevadded = true;
return 0;
}
static int
qemuSnapshotDiskPrepareOne(virDomainObjPtr vm,
virQEMUDriverConfigPtr cfg,
virDomainDiskDefPtr disk,
virDomainSnapshotDiskDefPtr snapdisk,
qemuSnapshotDiskDataPtr dd,
GHashTable *blockNamedNodeData,
bool reuse,
bool updateConfig,
qemuDomainAsyncJob asyncJob,
virJSONValuePtr actions)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
virQEMUDriverPtr driver = priv->driver;
bool blockdev = virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_BLOCKDEV);
virDomainDiskDefPtr persistdisk;
bool supportsCreate;
bool updateRelativeBacking = false;
dd->disk = disk;
if (qemuDomainStorageSourceValidateDepth(disk->src, 1, disk->dst) < 0)
return -1;
if (!(dd->src = virStorageSourceCopy(snapdisk->src, false)))
return -1;
if (virStorageSourceInitChainElement(dd->src, dd->disk->src, false) < 0)
return -1;
/* modify disk in persistent definition only when the source is the same */
if (updateConfig &&
vm->newDef &&
(persistdisk = virDomainDiskByTarget(vm->newDef, dd->disk->dst)) &&
virStorageSourceIsSameLocation(dd->disk->src, persistdisk->src)) {
dd->persistdisk = persistdisk;
if (!(dd->persistsrc = virStorageSourceCopy(dd->src, false)))
return -1;
if (virStorageSourceInitChainElement(dd->persistsrc,
dd->persistdisk->src, false) < 0)
return -1;
}
supportsCreate = virStorageSourceSupportsCreate(dd->src);
/* relative backing store paths need to be updated so that relative
* block commit still works. With blockdev we must update it when doing
* commit anyways so it's skipped here */
if (!blockdev &&
virStorageSourceSupportsBackingChainTraversal(dd->src))
updateRelativeBacking = true;
if (supportsCreate || updateRelativeBacking) {
if (qemuDomainStorageFileInit(driver, vm, dd->src, NULL) < 0)
return -1;
dd->initialized = true;
if (reuse) {
if (updateRelativeBacking &&
virStorageSourceFetchRelativeBackingPath(dd->src, &dd->relPath) < 0)
return -1;
} else {
/* pre-create the image file so that we can label it before handing it to qemu */
if (supportsCreate && dd->src->type != VIR_STORAGE_TYPE_BLOCK) {
if (virStorageSourceCreate(dd->src) < 0) {
virReportSystemError(errno, _("failed to create image file '%s'"),
NULLSTR(dd->src->path));
return -1;
}
dd->created = true;
}
}
}
/* set correct security, cgroup and locking options on the new image */
if (qemuDomainStorageSourceAccessAllow(driver, vm, dd->src,
false, true, true) < 0)
return -1;
dd->prepared = true;
if (blockdev) {
if (qemuSnapshotDiskPrepareOneBlockdev(driver, vm, dd, cfg, reuse,
blockNamedNodeData, asyncJob) < 0)
return -1;
if (qemuSnapshotDiskBitmapsPropagate(dd, actions, blockNamedNodeData) < 0)
return -1;
if (qemuBlockSnapshotAddBlockdev(actions, dd->disk, dd->src) < 0)
return -1;
} else {
if (qemuBlockSnapshotAddLegacy(actions, dd->disk, dd->src, reuse) < 0)
return -1;
}
return 0;
}
/**
* qemuSnapshotDiskPrepareActiveExternal:
*
* Collects and prepares a list of structures that hold information about disks
* that are selected for the snapshot.
*/
static qemuSnapshotDiskContextPtr
qemuSnapshotDiskPrepareActiveExternal(virDomainObjPtr vm,
virDomainMomentObjPtr snap,
virQEMUDriverConfigPtr cfg,
bool reuse,
GHashTable *blockNamedNodeData,
qemuDomainAsyncJob asyncJob)
{
g_autoptr(qemuSnapshotDiskContext) snapctxt = NULL;
size_t i;
virDomainSnapshotDefPtr snapdef = virDomainSnapshotObjGetDef(snap);
snapctxt = qemuSnapshotDiskContextNew(snapdef->ndisks, vm, asyncJob);
for (i = 0; i < snapdef->ndisks; i++) {
if (snapdef->disks[i].snapshot == VIR_DOMAIN_SNAPSHOT_LOCATION_NONE)
continue;
if (qemuSnapshotDiskPrepareOne(vm, cfg, vm->def->disks[i],
snapdef->disks + i,
snapctxt->dd + snapctxt->ndd++,
blockNamedNodeData,
reuse,
true,
asyncJob,
snapctxt->actions) < 0)
return NULL;
}
return g_steal_pointer(&snapctxt);
}
static qemuSnapshotDiskContextPtr
qemuSnapshotDiskPrepareDisksTransient(virDomainObjPtr vm,
virQEMUDriverConfigPtr cfg,
GHashTable *blockNamedNodeData,
qemuDomainAsyncJob asyncJob)
{
g_autoptr(qemuSnapshotDiskContext) snapctxt = NULL;
size_t i;
snapctxt = qemuSnapshotDiskContextNew(vm->def->ndisks, vm, asyncJob);
for (i = 0; i < vm->def->ndisks; i++) {
virDomainDiskDefPtr domdisk = vm->def->disks[i];
g_autoptr(virDomainSnapshotDiskDef) snapdisk = g_new0(virDomainSnapshotDiskDef, 1);
if (!domdisk->transient)
continue;
/* validation code makes sure that we do this only for local disks
* with a file source */
snapdisk->name = g_strdup(domdisk->dst);
snapdisk->snapshot = VIR_DOMAIN_SNAPSHOT_LOCATION_EXTERNAL;
snapdisk->src = virStorageSourceNew();
snapdisk->src->type = VIR_STORAGE_TYPE_FILE;
snapdisk->src->format = VIR_STORAGE_FILE_QCOW2;
snapdisk->src->path = g_strdup_printf("%s.TRANSIENT", domdisk->src->path);
if (virFileExists(snapdisk->src->path)) {
virReportError(VIR_ERR_OPERATION_UNSUPPORTED,
_("Overlay file '%s' for transient disk '%s' already exists"),
snapdisk->src->path, domdisk->dst);
return NULL;
}
if (qemuSnapshotDiskPrepareOne(vm, cfg, domdisk, snapdisk,
snapctxt->dd + snapctxt->ndd++,
blockNamedNodeData,
false,
false,
asyncJob,
snapctxt->actions) < 0)
return NULL;
}
return g_steal_pointer(&snapctxt);
}
static void
qemuSnapshotDiskUpdateSourceRenumber(virStorageSourcePtr src)
{
virStorageSourcePtr next;
unsigned int idx = 1;
for (next = src->backingStore; virStorageSourceIsBacking(next); next = next->backingStore)
next->id = idx++;
}
/**
* qemuSnapshotDiskUpdateSource:
* @vm: domain object
* @dd: snapshot disk data object
*
* Updates disk definition after a successful snapshot.
*/
static void
qemuSnapshotDiskUpdateSource(virDomainObjPtr vm,
qemuSnapshotDiskDataPtr dd)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
virQEMUDriverPtr driver = priv->driver;
/* storage driver access won'd be needed */
if (dd->initialized)
virStorageSourceDeinit(dd->src);
if (qemuSecurityMoveImageMetadata(driver, vm, dd->disk->src, dd->src) < 0)
VIR_WARN("Unable to move disk metadata on vm %s", vm->def->name);
/* unlock the write lock on the original image as qemu will no longer write to it */
virDomainLockImageDetach(driver->lockManager, vm, dd->disk->src);
/* unlock also the new image if the VM is paused to follow the locking semantics */
if (virDomainObjGetState(vm, NULL) != VIR_DOMAIN_RUNNING)
virDomainLockImageDetach(driver->lockManager, vm, dd->src);
/* the old disk image is now readonly */
dd->disk->src->readonly = true;
dd->disk->src->relPath = g_steal_pointer(&dd->relPath);
dd->src->backingStore = g_steal_pointer(&dd->disk->src);
dd->disk->src = g_steal_pointer(&dd->src);
/* fix numbering of disks */
if (!virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_BLOCKDEV))
qemuSnapshotDiskUpdateSourceRenumber(dd->disk->src);
if (dd->persistdisk) {
dd->persistdisk->src->readonly = true;
dd->persistsrc->backingStore = g_steal_pointer(&dd->persistdisk->src);
dd->persistdisk->src = g_steal_pointer(&dd->persistsrc);
}
}
static int
qemuSnapshotDiskCreate(qemuSnapshotDiskContextPtr snapctxt,
virQEMUDriverConfigPtr cfg)
{
qemuDomainObjPrivatePtr priv = snapctxt->vm->privateData;
virQEMUDriverPtr driver = priv->driver;
size_t i;
int rc;
/* check whether there's anything to do */
if (snapctxt->ndd == 0)
return 0;
if (qemuDomainObjEnterMonitorAsync(driver, snapctxt->vm, snapctxt->asyncJob) < 0)
return -1;
rc = qemuMonitorTransaction(priv->mon, &snapctxt->actions);
if (qemuDomainObjExitMonitor(driver, snapctxt->vm) < 0)
rc = -1;
for (i = 0; i < snapctxt->ndd; i++) {
qemuSnapshotDiskDataPtr dd = snapctxt->dd + i;
virDomainAuditDisk(snapctxt->vm, dd->disk->src, dd->src, "snapshot", rc >= 0);
if (rc == 0)
qemuSnapshotDiskUpdateSource(snapctxt->vm, dd);
}
if (rc < 0)
return -1;
if (virDomainObjSave(snapctxt->vm, driver->xmlopt, cfg->stateDir) < 0 ||
(snapctxt->vm->newDef && virDomainDefSave(snapctxt->vm->newDef, driver->xmlopt,
cfg->configDir) < 0))
return -1;
return 0;
}
/* The domain is expected to be locked and active. */
static int
qemuSnapshotCreateActiveExternalDisks(virDomainObjPtr vm,
virDomainMomentObjPtr snap,
GHashTable *blockNamedNodeData,
unsigned int flags,
virQEMUDriverConfigPtr cfg,
qemuDomainAsyncJob asyncJob)
{
bool reuse = (flags & VIR_DOMAIN_SNAPSHOT_CREATE_REUSE_EXT) != 0;
g_autoptr(qemuSnapshotDiskContext) snapctxt = NULL;
if (virDomainObjCheckActive(vm) < 0)
return -1;
/* prepare a list of objects to use in the vm definition so that we don't
* have to roll back later */
if (!(snapctxt = qemuSnapshotDiskPrepareActiveExternal(vm, snap, cfg, reuse,
blockNamedNodeData, asyncJob)))
return -1;
if (qemuSnapshotDiskCreate(snapctxt, cfg) < 0)
return -1;
return 0;
}
/**
* qemuSnapshotCreateDisksTransient:
* @vm: domain object
* @asyncJob: qemu async job type
*
* Creates overlays on top of disks which are configured as . Note
* that the validation code ensures that disks have appropriate
* configuration.
*/
int
qemuSnapshotCreateDisksTransient(virDomainObjPtr vm,
qemuDomainAsyncJob asyncJob)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
virQEMUDriverPtr driver = priv->driver;
g_autoptr(virQEMUDriverConfig) cfg = virQEMUDriverGetConfig(driver);
g_autoptr(qemuSnapshotDiskContext) snapctxt = NULL;
g_autoptr(GHashTable) blockNamedNodeData = NULL;
if (virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_BLOCKDEV)) {
if (!(blockNamedNodeData = qemuBlockGetNamedNodeData(vm, asyncJob)))
return -1;
if (!(snapctxt = qemuSnapshotDiskPrepareDisksTransient(vm, cfg,
blockNamedNodeData,
asyncJob)))
return -1;
if (qemuSnapshotDiskCreate(snapctxt, cfg) < 0)
return -1;
}
/* the overlays are established, so they can be deleted on shutdown */
priv->inhibitDiskTransientDelete = false;
return 0;
}
static int
qemuSnapshotCreateActiveExternal(virQEMUDriverPtr driver,
virDomainObjPtr vm,
virDomainMomentObjPtr snap,
virQEMUDriverConfigPtr cfg,
unsigned int flags)
{
virObjectEventPtr event;
bool resume = false;
int ret = -1;
qemuDomainObjPrivatePtr priv = vm->privateData;
g_autofree char *xml = NULL;
virDomainSnapshotDefPtr snapdef = virDomainSnapshotObjGetDef(snap);
bool memory = snapdef->memory == VIR_DOMAIN_SNAPSHOT_LOCATION_EXTERNAL;
bool memory_unlink = false;
bool thaw = false;
bool pmsuspended = false;
int compressed;
g_autoptr(virCommand) compressor = NULL;
virQEMUSaveDataPtr data = NULL;
g_autoptr(GHashTable) blockNamedNodeData = NULL;
/* If quiesce was requested, then issue a freeze command, and a
* counterpart thaw command when it is actually sent to agent.
* The command will fail if the guest is paused or the guest agent
* is not running, or is already quiesced. */
if (flags & VIR_DOMAIN_SNAPSHOT_CREATE_QUIESCE) {
int frozen;
if (qemuDomainObjBeginAgentJob(driver, vm, QEMU_AGENT_JOB_MODIFY) < 0)
goto cleanup;
if (virDomainObjCheckActive(vm) < 0) {
qemuDomainObjEndAgentJob(vm);
goto cleanup;
}
frozen = qemuSnapshotFSFreeze(vm, NULL, 0);
qemuDomainObjEndAgentJob(vm);
if (frozen < 0)
goto cleanup;
if (frozen > 0)
thaw = true;
}
/* We need to track what state the guest is in, since taking the
* snapshot may alter that state and we must restore it later. */
if (virDomainObjGetState(vm, NULL) == VIR_DOMAIN_PMSUSPENDED) {
pmsuspended = true;
} else if (virDomainObjGetState(vm, NULL) == VIR_DOMAIN_RUNNING) {
/* For full system external snapshots (those with memory), the guest
* must pause (either by libvirt up front, or by qemu after
* _LIVE converges). */
if (memory)
resume = true;
if (memory && !(flags & VIR_DOMAIN_SNAPSHOT_CREATE_LIVE)) {
if (qemuProcessStopCPUs(driver, vm, VIR_DOMAIN_PAUSED_SNAPSHOT,
QEMU_ASYNC_JOB_SNAPSHOT) < 0)
goto cleanup;
if (!virDomainObjIsActive(vm)) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("guest unexpectedly quit"));
goto cleanup;
}
resume = true;
}
}
/* We need to collect reply from 'query-named-block-nodes' prior to the
* migration step as qemu deactivates bitmaps after migration so the result
* would be wrong */
if (virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_BLOCKDEV) &&
!(blockNamedNodeData = qemuBlockGetNamedNodeData(vm, QEMU_ASYNC_JOB_SNAPSHOT)))
goto cleanup;
/* do the memory snapshot if necessary */
if (memory) {
/* check if migration is possible */
if (!qemuMigrationSrcIsAllowed(driver, vm, false, 0))
goto cleanup;
priv->job.current->statsType = QEMU_DOMAIN_JOB_STATS_TYPE_SAVEDUMP;
/* allow the migration job to be cancelled or the domain to be paused */
qemuDomainObjSetAsyncJobMask(vm, (QEMU_JOB_DEFAULT_MASK |
JOB_MASK(QEMU_JOB_SUSPEND) |
JOB_MASK(QEMU_JOB_MIGRATION_OP)));
if ((compressed = qemuSaveImageGetCompressionProgram(cfg->snapshotImageFormat,
&compressor,
"snapshot", false)) < 0)
goto cleanup;
if (!(xml = qemuDomainDefFormatLive(driver, priv->qemuCaps,
vm->def, priv->origCPU,
true, true)) ||
!(snapdef->cookie = (virObjectPtr) qemuDomainSaveCookieNew(vm)))
goto cleanup;
if (!(data = virQEMUSaveDataNew(xml,
(qemuDomainSaveCookiePtr) snapdef->cookie,
resume, compressed, driver->xmlopt)))
goto cleanup;
xml = NULL;
if ((ret = qemuSaveImageCreate(driver, vm, snapdef->file, data,
compressor, 0,
QEMU_ASYNC_JOB_SNAPSHOT)) < 0)
goto cleanup;
/* the memory image was created, remove it on errors */
memory_unlink = true;
/* forbid any further manipulation */
qemuDomainObjSetAsyncJobMask(vm, QEMU_JOB_DEFAULT_MASK);
}
/* the domain is now paused if a memory snapshot was requested */
if ((ret = qemuSnapshotCreateActiveExternalDisks(vm, snap,
blockNamedNodeData, flags, cfg,
QEMU_ASYNC_JOB_SNAPSHOT)) < 0)
goto cleanup;
/* the snapshot is complete now */
if (flags & VIR_DOMAIN_SNAPSHOT_CREATE_HALT) {
event = virDomainEventLifecycleNewFromObj(vm, VIR_DOMAIN_EVENT_STOPPED,
VIR_DOMAIN_EVENT_STOPPED_FROM_SNAPSHOT);
qemuProcessStop(driver, vm, VIR_DOMAIN_SHUTOFF_FROM_SNAPSHOT,
QEMU_ASYNC_JOB_SNAPSHOT, 0);
virDomainAuditStop(vm, "from-snapshot");
resume = false;
thaw = false;
virObjectEventStateQueue(driver->domainEventState, event);
} else if (memory && pmsuspended) {
/* qemu 1.3 is unable to save a domain in pm-suspended (S3)
* state; so we must emit an event stating that it was
* converted to paused. */
virDomainObjSetState(vm, VIR_DOMAIN_PAUSED,
VIR_DOMAIN_PAUSED_FROM_SNAPSHOT);
event = virDomainEventLifecycleNewFromObj(vm, VIR_DOMAIN_EVENT_SUSPENDED,
VIR_DOMAIN_EVENT_SUSPENDED_FROM_SNAPSHOT);
virObjectEventStateQueue(driver->domainEventState, event);
}
ret = 0;
cleanup:
if (resume && virDomainObjIsActive(vm) &&
qemuProcessStartCPUs(driver, vm,
VIR_DOMAIN_RUNNING_UNPAUSED,
QEMU_ASYNC_JOB_SNAPSHOT) < 0) {
event = virDomainEventLifecycleNewFromObj(vm,
VIR_DOMAIN_EVENT_SUSPENDED,
VIR_DOMAIN_EVENT_SUSPENDED_API_ERROR);
virObjectEventStateQueue(driver->domainEventState, event);
if (virGetLastErrorCode() == VIR_ERR_OK) {
virReportError(VIR_ERR_OPERATION_FAILED, "%s",
_("resuming after snapshot failed"));
}
ret = -1;
}
if (thaw &&
qemuDomainObjBeginAgentJob(driver, vm, QEMU_AGENT_JOB_MODIFY) >= 0 &&
virDomainObjIsActive(vm)) {
/* report error only on an otherwise successful snapshot */
if (qemuSnapshotFSThaw(vm, ret == 0) < 0)
ret = -1;
qemuDomainObjEndAgentJob(vm);
}
virQEMUSaveDataFree(data);
if (memory_unlink && ret < 0)
unlink(snapdef->file);
return ret;
}
virDomainSnapshotPtr
qemuSnapshotCreateXML(virDomainPtr domain,
virDomainObjPtr vm,
const char *xmlDesc,
unsigned int flags)
{
virQEMUDriverPtr driver = domain->conn->privateData;
g_autofree char *xml = NULL;
virDomainMomentObjPtr snap = NULL;
virDomainSnapshotPtr snapshot = NULL;
virDomainMomentObjPtr current = NULL;
bool update_current = true;
bool redefine = flags & VIR_DOMAIN_SNAPSHOT_CREATE_REDEFINE;
unsigned int parse_flags = VIR_DOMAIN_SNAPSHOT_PARSE_DISKS;
int align_location = VIR_DOMAIN_SNAPSHOT_LOCATION_INTERNAL;
bool align_match = true;
g_autoptr(virQEMUDriverConfig) cfg = virQEMUDriverGetConfig(driver);
qemuDomainObjPrivatePtr priv = vm->privateData;
virDomainSnapshotState state;
g_autoptr(virDomainSnapshotDef) def = NULL;
virCheckFlags(VIR_DOMAIN_SNAPSHOT_CREATE_REDEFINE |
VIR_DOMAIN_SNAPSHOT_CREATE_CURRENT |
VIR_DOMAIN_SNAPSHOT_CREATE_NO_METADATA |
VIR_DOMAIN_SNAPSHOT_CREATE_HALT |
VIR_DOMAIN_SNAPSHOT_CREATE_DISK_ONLY |
VIR_DOMAIN_SNAPSHOT_CREATE_REUSE_EXT |
VIR_DOMAIN_SNAPSHOT_CREATE_QUIESCE |
VIR_DOMAIN_SNAPSHOT_CREATE_ATOMIC |
VIR_DOMAIN_SNAPSHOT_CREATE_LIVE |
VIR_DOMAIN_SNAPSHOT_CREATE_VALIDATE, NULL);
VIR_REQUIRE_FLAG_RET(VIR_DOMAIN_SNAPSHOT_CREATE_QUIESCE,
VIR_DOMAIN_SNAPSHOT_CREATE_DISK_ONLY,
NULL);
VIR_EXCLUSIVE_FLAGS_RET(VIR_DOMAIN_SNAPSHOT_CREATE_LIVE,
VIR_DOMAIN_SNAPSHOT_CREATE_REDEFINE,
NULL);
if ((redefine && !(flags & VIR_DOMAIN_SNAPSHOT_CREATE_CURRENT)) ||
(flags & VIR_DOMAIN_SNAPSHOT_CREATE_NO_METADATA))
update_current = false;
if (redefine)
parse_flags |= VIR_DOMAIN_SNAPSHOT_PARSE_REDEFINE;
if (qemuDomainSupportsCheckpointsBlockjobs(vm) < 0)
goto cleanup;
if (!vm->persistent && (flags & VIR_DOMAIN_SNAPSHOT_CREATE_HALT)) {
virReportError(VIR_ERR_OPERATION_INVALID, "%s",
_("cannot halt after transient domain snapshot"));
goto cleanup;
}
if ((flags & VIR_DOMAIN_SNAPSHOT_CREATE_DISK_ONLY) ||
!virDomainObjIsActive(vm))
parse_flags |= VIR_DOMAIN_SNAPSHOT_PARSE_OFFLINE;
if (flags & VIR_DOMAIN_SNAPSHOT_CREATE_VALIDATE)
parse_flags |= VIR_DOMAIN_SNAPSHOT_PARSE_VALIDATE;
if (!(def = virDomainSnapshotDefParseString(xmlDesc, driver->xmlopt,
priv->qemuCaps, NULL, parse_flags)))
goto cleanup;
/* reject snapshot names containing slashes or starting with dot as
* snapshot definitions are saved in files named by the snapshot name */
if (!(flags & VIR_DOMAIN_SNAPSHOT_CREATE_NO_METADATA)) {
if (strchr(def->parent.name, '/')) {
virReportError(VIR_ERR_XML_DETAIL,
_("invalid snapshot name '%s': "
"name can't contain '/'"),
def->parent.name);
goto cleanup;
}
if (def->parent.name[0] == '.') {
virReportError(VIR_ERR_XML_DETAIL,
_("invalid snapshot name '%s': "
"name can't start with '.'"),
def->parent.name);
goto cleanup;
}
}
/* reject the VIR_DOMAIN_SNAPSHOT_CREATE_LIVE flag where not supported */
if (flags & VIR_DOMAIN_SNAPSHOT_CREATE_LIVE &&
(!virDomainObjIsActive(vm) ||
def->memory != VIR_DOMAIN_SNAPSHOT_LOCATION_EXTERNAL)) {
virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s",
_("live snapshot creation is supported only "
"during full system snapshots"));
goto cleanup;
}
/* allow snapshots only in certain states */
state = redefine ? def->state : vm->state.state;
switch (state) {
/* valid states */
case VIR_DOMAIN_SNAPSHOT_RUNNING:
case VIR_DOMAIN_SNAPSHOT_PAUSED:
case VIR_DOMAIN_SNAPSHOT_SHUTDOWN:
case VIR_DOMAIN_SNAPSHOT_SHUTOFF:
case VIR_DOMAIN_SNAPSHOT_CRASHED:
break;
case VIR_DOMAIN_SNAPSHOT_DISK_SNAPSHOT:
if (!redefine) {
virReportError(VIR_ERR_INTERNAL_ERROR, _("Invalid domain state %s"),
virDomainSnapshotStateTypeToString(state));
goto cleanup;
}
break;
case VIR_DOMAIN_SNAPSHOT_PMSUSPENDED:
virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s",
_("qemu doesn't support taking snapshots of "
"PMSUSPENDED guests"));
goto cleanup;
/* invalid states */
case VIR_DOMAIN_SNAPSHOT_NOSTATE:
case VIR_DOMAIN_SNAPSHOT_BLOCKED: /* invalid state, unused in qemu */
case VIR_DOMAIN_SNAPSHOT_LAST:
virReportError(VIR_ERR_INTERNAL_ERROR, _("Invalid domain state %s"),
virDomainSnapshotStateTypeToString(state));
goto cleanup;
}
/* We are going to modify the domain below. Internal snapshots would use
* a regular job, so we need to set the job mask to disallow query as
* 'savevm' blocks the monitor. External snapshot will then modify the
* job mask appropriately. */
if (qemuDomainObjBeginAsyncJob(driver, vm, QEMU_ASYNC_JOB_SNAPSHOT,
VIR_DOMAIN_JOB_OPERATION_SNAPSHOT, flags) < 0)
goto cleanup;
qemuDomainObjSetAsyncJobMask(vm, QEMU_JOB_NONE);
if (redefine) {
if (virDomainSnapshotRedefinePrep(vm, &def, &snap,
driver->xmlopt,
flags) < 0)
goto endjob;
} else {
/* Easiest way to clone inactive portion of vm->def is via
* conversion in and back out of xml. */
if (!(xml = qemuDomainDefFormatLive(driver, priv->qemuCaps,
vm->def, priv->origCPU,
true, true)) ||
!(def->parent.dom = virDomainDefParseString(xml, driver->xmlopt,
priv->qemuCaps,
VIR_DOMAIN_DEF_PARSE_INACTIVE |
VIR_DOMAIN_DEF_PARSE_SKIP_VALIDATE)))
goto endjob;
if (vm->newDef) {
def->parent.inactiveDom = virDomainDefCopy(vm->newDef,
driver->xmlopt, priv->qemuCaps, true);
if (!def->parent.inactiveDom)
goto endjob;
}
if (flags & VIR_DOMAIN_SNAPSHOT_CREATE_DISK_ONLY) {
align_location = VIR_DOMAIN_SNAPSHOT_LOCATION_EXTERNAL;
align_match = false;
if (virDomainObjIsActive(vm))
def->state = VIR_DOMAIN_SNAPSHOT_DISK_SNAPSHOT;
else
def->state = VIR_DOMAIN_SNAPSHOT_SHUTOFF;
def->memory = VIR_DOMAIN_SNAPSHOT_LOCATION_NONE;
} else if (def->memory == VIR_DOMAIN_SNAPSHOT_LOCATION_EXTERNAL) {
def->state = virDomainObjGetState(vm, NULL);
align_location = VIR_DOMAIN_SNAPSHOT_LOCATION_EXTERNAL;
align_match = false;
} else {
def->state = virDomainObjGetState(vm, NULL);
if (virDomainObjIsActive(vm) &&
def->memory == VIR_DOMAIN_SNAPSHOT_LOCATION_NONE) {
virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s",
_("internal snapshot of a running VM "
"must include the memory state"));
goto endjob;
}
def->memory = (def->state == VIR_DOMAIN_SNAPSHOT_SHUTOFF ?
VIR_DOMAIN_SNAPSHOT_LOCATION_NONE :
VIR_DOMAIN_SNAPSHOT_LOCATION_INTERNAL);
}
if (virDomainSnapshotAlignDisks(def, align_location,
align_match) < 0 ||
qemuSnapshotPrepare(vm, def, &flags) < 0)
goto endjob;
}
if (!snap) {
if (!(snap = virDomainSnapshotAssignDef(vm->snapshots, def)))
goto endjob;
def = NULL;
}
current = virDomainSnapshotGetCurrent(vm->snapshots);
if (current) {
if (!redefine)
snap->def->parent_name = g_strdup(current->def->name);
}
/* actually do the snapshot */
if (redefine) {
/* XXX Should we validate that the redefined snapshot even
* makes sense, such as checking that qemu-img recognizes the
* snapshot name in at least one of the domain's disks? */
} else if (virDomainObjIsActive(vm)) {
if (flags & VIR_DOMAIN_SNAPSHOT_CREATE_DISK_ONLY ||
virDomainSnapshotObjGetDef(snap)->memory == VIR_DOMAIN_SNAPSHOT_LOCATION_EXTERNAL) {
/* external full system or disk snapshot */
if (qemuSnapshotCreateActiveExternal(driver, vm, snap, cfg, flags) < 0)
goto endjob;
} else {
/* internal full system */
if (qemuSnapshotCreateActiveInternal(driver, vm, snap, flags) < 0)
goto endjob;
}
} else {
/* inactive; qemuSnapshotPrepare guaranteed that we
* aren't mixing internal and external, and altered flags to
* contain DISK_ONLY if there is an external disk. */
if (flags & VIR_DOMAIN_SNAPSHOT_CREATE_DISK_ONLY) {
bool reuse = !!(flags & VIR_DOMAIN_SNAPSHOT_CREATE_REUSE_EXT);
if (qemuSnapshotCreateInactiveExternal(driver, vm, snap, reuse) < 0)
goto endjob;
} else {
if (qemuSnapshotCreateInactiveInternal(driver, vm, snap) < 0)
goto endjob;
}
}
/* If we fail after this point, there's not a whole lot we can
* do; we've successfully taken the snapshot, and we are now running
* on it, so we have to go forward the best we can
*/
snapshot = virGetDomainSnapshot(domain, snap->def->name);
endjob:
if (snapshot && !(flags & VIR_DOMAIN_SNAPSHOT_CREATE_NO_METADATA)) {
if (update_current)
qemuSnapshotSetCurrent(vm, snap);
if (qemuDomainSnapshotWriteMetadata(vm, snap,
driver->xmlopt,
cfg->snapshotDir) < 0) {
/* if writing of metadata fails, error out rather than trying
* to silently carry on without completing the snapshot */
virObjectUnref(snapshot);
snapshot = NULL;
virReportError(VIR_ERR_INTERNAL_ERROR,
_("unable to save metadata for snapshot %s"),
snap->def->name);
virDomainSnapshotObjListRemove(vm->snapshots, snap);
} else {
virDomainSnapshotLinkParent(vm->snapshots, snap);
}
} else if (snap) {
virDomainSnapshotObjListRemove(vm->snapshots, snap);
}
qemuDomainObjEndAsyncJob(driver, vm);
cleanup:
return snapshot;
}
/* The domain is expected to be locked and inactive. */
static int
qemuSnapshotRevertInactive(virQEMUDriverPtr driver,
virDomainObjPtr vm,
virDomainMomentObjPtr snap)
{
/* Prefer action on the disks in use at the time the snapshot was
* created; but fall back to current definition if dealing with a
* snapshot created prior to libvirt 0.9.5. */
virDomainDefPtr def = snap->def->dom;
if (!def)
def = vm->def;
/* Try all disks, but report failure if we skipped any. */
if (qemuDomainSnapshotForEachQcow2(driver, def, snap, "-a", true) != 0)
return -1;
return 0;
}
int
qemuSnapshotRevert(virDomainObjPtr vm,
virDomainSnapshotPtr snapshot,
unsigned int flags)
{
virQEMUDriverPtr driver = snapshot->domain->conn->privateData;
int ret = -1;
virDomainMomentObjPtr snap = NULL;
virDomainSnapshotDefPtr snapdef;
virObjectEventPtr event = NULL;
virObjectEventPtr event2 = NULL;
int detail;
qemuDomainObjPrivatePtr priv = vm->privateData;
int rc;
virDomainDefPtr config = NULL;
virDomainDefPtr inactiveConfig = NULL;
g_autoptr(virQEMUDriverConfig) cfg = virQEMUDriverGetConfig(driver);
bool was_stopped = false;
qemuDomainSaveCookiePtr cookie;
virCPUDefPtr origCPU = NULL;
unsigned int start_flags = VIR_QEMU_PROCESS_START_GEN_VMID;
bool defined = false;
virCheckFlags(VIR_DOMAIN_SNAPSHOT_REVERT_RUNNING |
VIR_DOMAIN_SNAPSHOT_REVERT_PAUSED |
VIR_DOMAIN_SNAPSHOT_REVERT_FORCE, -1);
/* We have the following transitions, which create the following events:
* 1. inactive -> inactive: none
* 2. inactive -> running: EVENT_STARTED
* 3. inactive -> paused: EVENT_STARTED, EVENT_PAUSED
* 4. running -> inactive: EVENT_STOPPED
* 5. running -> running: none
* 6. running -> paused: EVENT_PAUSED
* 7. paused -> inactive: EVENT_STOPPED
* 8. paused -> running: EVENT_RESUMED
* 9. paused -> paused: none
* Also, several transitions occur even if we fail partway through,
* and use of FORCE can cause multiple transitions.
*/
if (qemuDomainHasBlockjob(vm, false)) {
virReportError(VIR_ERR_OPERATION_INVALID, "%s",
_("domain has active block job"));
goto cleanup;
}
if (qemuProcessBeginJob(driver, vm,
VIR_DOMAIN_JOB_OPERATION_SNAPSHOT_REVERT,
flags) < 0)
goto cleanup;
if (!(snap = qemuSnapObjFromSnapshot(vm, snapshot)))
goto endjob;
snapdef = virDomainSnapshotObjGetDef(snap);
if (!vm->persistent &&
snapdef->state != VIR_DOMAIN_SNAPSHOT_RUNNING &&
snapdef->state != VIR_DOMAIN_SNAPSHOT_PAUSED &&
(flags & (VIR_DOMAIN_SNAPSHOT_REVERT_RUNNING |
VIR_DOMAIN_SNAPSHOT_REVERT_PAUSED)) == 0) {
virReportError(VIR_ERR_OPERATION_INVALID, "%s",
_("transient domain needs to request run or pause "
"to revert to inactive snapshot"));
goto endjob;
}
if (virDomainSnapshotIsExternal(snap)) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("revert to external snapshot not supported yet"));
goto endjob;
}
if (!(flags & VIR_DOMAIN_SNAPSHOT_REVERT_FORCE)) {
if (!snap->def->dom) {
virReportError(VIR_ERR_SNAPSHOT_REVERT_RISKY,
_("snapshot '%s' lacks domain '%s' rollback info"),
snap->def->name, vm->def->name);
goto endjob;
}
if (virDomainObjIsActive(vm) &&
!(snapdef->state == VIR_DOMAIN_SNAPSHOT_RUNNING ||
snapdef->state == VIR_DOMAIN_SNAPSHOT_PAUSED) &&
(flags & (VIR_DOMAIN_SNAPSHOT_REVERT_RUNNING |
VIR_DOMAIN_SNAPSHOT_REVERT_PAUSED))) {
virReportError(VIR_ERR_SNAPSHOT_REVERT_RISKY, "%s",
_("must respawn qemu to start inactive snapshot"));
goto endjob;
}
if (vm->hasManagedSave &&
!(snapdef->state == VIR_DOMAIN_SNAPSHOT_RUNNING ||
snapdef->state == VIR_DOMAIN_SNAPSHOT_PAUSED)) {
virReportError(VIR_ERR_SNAPSHOT_REVERT_RISKY, "%s",
_("snapshot without memory state, removal of "
"existing managed saved state strongly "
"recommended to avoid corruption"));
goto endjob;
}
}
if (snap->def->dom) {
config = virDomainDefCopy(snap->def->dom,
driver->xmlopt, priv->qemuCaps, true);
if (!config)
goto endjob;
if (STRNEQ(config->name, vm->def->name)) {
VIR_FREE(config->name);
config->name = g_strdup(vm->def->name);
}
}
if (snap->def->inactiveDom) {
inactiveConfig = virDomainDefCopy(snap->def->inactiveDom,
driver->xmlopt, priv->qemuCaps, true);
if (!inactiveConfig)
goto endjob;
if (STRNEQ(inactiveConfig->name, vm->def->name)) {
VIR_FREE(inactiveConfig->name);
inactiveConfig->name = g_strdup(vm->def->name);
}
} else {
/* Inactive domain definition is missing:
* - either this is an old active snapshot and we need to copy the
* active definition as an inactive one
* - or this is an inactive snapshot which means config contains the
* inactive definition.
*/
if (snapdef->state == VIR_DOMAIN_SNAPSHOT_RUNNING ||
snapdef->state == VIR_DOMAIN_SNAPSHOT_PAUSED) {
inactiveConfig = virDomainDefCopy(snap->def->dom,
driver->xmlopt, priv->qemuCaps, true);
if (!inactiveConfig)
goto endjob;
} else {
inactiveConfig = g_steal_pointer(&config);
}
}
cookie = (qemuDomainSaveCookiePtr) snapdef->cookie;
switch ((virDomainSnapshotState) snapdef->state) {
case VIR_DOMAIN_SNAPSHOT_RUNNING:
case VIR_DOMAIN_SNAPSHOT_PAUSED:
start_flags |= VIR_QEMU_PROCESS_START_PAUSED;
/* Transitions 2, 3, 5, 6, 8, 9 */
/* When using the loadvm monitor command, qemu does not know
* whether to pause or run the reverted domain, and just stays
* in the same state as before the monitor command, whether
* that is paused or running. We always pause before loadvm,
* to have finer control. */
if (virDomainObjIsActive(vm)) {
/* Transitions 5, 6, 8, 9 */
/* Check for ABI compatibility. We need to do this check against
* the migratable XML or it will always fail otherwise */
if (config) {
bool compatible;
/* Replace the CPU in config and put the original one in priv
* once we're done. When we have the updated CPU def in the
* cookie, we don't want to replace the CPU in migratable def
* when doing ABI checks to make sure the current CPU exactly
* matches the one used at the time the snapshot was taken.
*/
if (cookie && cookie->cpu && config->cpu) {
origCPU = config->cpu;
if (!(config->cpu = virCPUDefCopy(cookie->cpu)))
goto endjob;
compatible = qemuDomainDefCheckABIStability(driver,
priv->qemuCaps,
vm->def,
config);
} else {
compatible = qemuDomainCheckABIStability(driver, vm, config);
}
/* If using VM GenID, there is no way currently to change
* the genid for the running guest, so set an error,
* mark as incompatible, and don't allow change of genid
* if the revert force flag would start the guest again. */
if (compatible && config->genidRequested) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
_("domain genid update requires restart"));
compatible = false;
start_flags &= ~VIR_QEMU_PROCESS_START_GEN_VMID;
}
if (!compatible) {
virErrorPtr err = virGetLastError();
if (!(flags & VIR_DOMAIN_SNAPSHOT_REVERT_FORCE)) {
/* Re-spawn error using correct category. */
if (err->code == VIR_ERR_CONFIG_UNSUPPORTED)
virReportError(VIR_ERR_SNAPSHOT_REVERT_RISKY, "%s",
err->str2);
goto endjob;
}
virResetError(err);
qemuProcessStop(driver, vm,
VIR_DOMAIN_SHUTOFF_FROM_SNAPSHOT,
QEMU_ASYNC_JOB_START, 0);
virDomainAuditStop(vm, "from-snapshot");
detail = VIR_DOMAIN_EVENT_STOPPED_FROM_SNAPSHOT;
event = virDomainEventLifecycleNewFromObj(vm,
VIR_DOMAIN_EVENT_STOPPED,
detail);
virObjectEventStateQueue(driver->domainEventState, event);
goto load;
}
}
if (virDomainObjGetState(vm, NULL) == VIR_DOMAIN_RUNNING) {
/* Transitions 5, 6 */
if (qemuProcessStopCPUs(driver, vm,
VIR_DOMAIN_PAUSED_FROM_SNAPSHOT,
QEMU_ASYNC_JOB_START) < 0)
goto endjob;
if (!virDomainObjIsActive(vm)) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("guest unexpectedly quit"));
goto endjob;
}
}
if (qemuDomainObjEnterMonitorAsync(driver, vm,
QEMU_ASYNC_JOB_START) < 0)
goto endjob;
rc = qemuMonitorLoadSnapshot(priv->mon, snap->def->name);
if (qemuDomainObjExitMonitor(driver, vm) < 0)
goto endjob;
if (rc < 0) {
/* XXX resume domain if it was running before the
* failed loadvm attempt? */
goto endjob;
}
if (config) {
virCPUDefFree(priv->origCPU);
priv->origCPU = g_steal_pointer(&origCPU);
}
if (cookie && !cookie->slirpHelper)
priv->disableSlirp = true;
if (inactiveConfig) {
virDomainObjAssignDef(vm, inactiveConfig, false, NULL);
inactiveConfig = NULL;
defined = true;
}
} else {
/* Transitions 2, 3 */
load:
was_stopped = true;
if (inactiveConfig) {
virDomainObjAssignDef(vm, inactiveConfig, false, NULL);
inactiveConfig = NULL;
defined = true;
}
if (config) {
virDomainObjAssignDef(vm, config, true, NULL);
config = NULL;
}
/* No cookie means libvirt which saved the domain was too old to
* mess up the CPU definitions.
*/
if (cookie &&
qemuDomainFixupCPUs(vm, &cookie->cpu) < 0)
goto cleanup;
rc = qemuProcessStart(snapshot->domain->conn, driver, vm,
cookie ? cookie->cpu : NULL,
QEMU_ASYNC_JOB_START, NULL, -1, NULL, snap,
VIR_NETDEV_VPORT_PROFILE_OP_CREATE,
start_flags);
virDomainAuditStart(vm, "from-snapshot", rc >= 0);
detail = VIR_DOMAIN_EVENT_STARTED_FROM_SNAPSHOT;
event = virDomainEventLifecycleNewFromObj(vm,
VIR_DOMAIN_EVENT_STARTED,
detail);
if (rc < 0)
goto endjob;
}
/* Touch up domain state. */
if (!(flags & VIR_DOMAIN_SNAPSHOT_REVERT_RUNNING) &&
(snapdef->state == VIR_DOMAIN_SNAPSHOT_PAUSED ||
(flags & VIR_DOMAIN_SNAPSHOT_REVERT_PAUSED))) {
/* Transitions 3, 6, 9 */
virDomainObjSetState(vm, VIR_DOMAIN_PAUSED,
VIR_DOMAIN_PAUSED_FROM_SNAPSHOT);
if (was_stopped) {
/* Transition 3, use event as-is and add event2 */
detail = VIR_DOMAIN_EVENT_SUSPENDED_FROM_SNAPSHOT;
event2 = virDomainEventLifecycleNewFromObj(vm,
VIR_DOMAIN_EVENT_SUSPENDED,
detail);
} /* else transition 6 and 9 use event as-is */
} else {
/* Transitions 2, 5, 8 */
if (!virDomainObjIsActive(vm)) {
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
_("guest unexpectedly quit"));
goto endjob;
}
rc = qemuProcessStartCPUs(driver, vm,
VIR_DOMAIN_RUNNING_FROM_SNAPSHOT,
QEMU_ASYNC_JOB_START);
if (rc < 0)
goto endjob;
virObjectUnref(event);
event = NULL;
if (was_stopped) {
/* Transition 2 */
detail = VIR_DOMAIN_EVENT_STARTED_FROM_SNAPSHOT;
event = virDomainEventLifecycleNewFromObj(vm,
VIR_DOMAIN_EVENT_STARTED,
detail);
}
}
break;
case VIR_DOMAIN_SNAPSHOT_SHUTDOWN:
case VIR_DOMAIN_SNAPSHOT_SHUTOFF:
case VIR_DOMAIN_SNAPSHOT_CRASHED:
/* Transitions 1, 4, 7 */
/* Newer qemu -loadvm refuses to revert to the state of a snapshot
* created by qemu-img snapshot -c. If the domain is running, we
* must take it offline; then do the revert using qemu-img.
*/
if (virDomainObjIsActive(vm)) {
/* Transitions 4, 7 */
qemuProcessStop(driver, vm, VIR_DOMAIN_SHUTOFF_FROM_SNAPSHOT,
QEMU_ASYNC_JOB_START, 0);
virDomainAuditStop(vm, "from-snapshot");
detail = VIR_DOMAIN_EVENT_STOPPED_FROM_SNAPSHOT;
event = virDomainEventLifecycleNewFromObj(vm,
VIR_DOMAIN_EVENT_STOPPED,
detail);
}
if (qemuSnapshotRevertInactive(driver, vm, snap) < 0) {
qemuDomainRemoveInactive(driver, vm);
qemuProcessEndJob(driver, vm);
goto cleanup;
}
if (inactiveConfig) {
virDomainObjAssignDef(vm, inactiveConfig, false, NULL);
inactiveConfig = NULL;
defined = true;
}
if (flags & (VIR_DOMAIN_SNAPSHOT_REVERT_RUNNING |
VIR_DOMAIN_SNAPSHOT_REVERT_PAUSED)) {
/* Flush first event, now do transition 2 or 3 */
bool paused = (flags & VIR_DOMAIN_SNAPSHOT_REVERT_PAUSED) != 0;
start_flags |= paused ? VIR_QEMU_PROCESS_START_PAUSED : 0;
virObjectEventStateQueue(driver->domainEventState, event);
rc = qemuProcessStart(snapshot->domain->conn, driver, vm, NULL,
QEMU_ASYNC_JOB_START, NULL, -1, NULL, NULL,
VIR_NETDEV_VPORT_PROFILE_OP_CREATE,
start_flags);
virDomainAuditStart(vm, "from-snapshot", rc >= 0);
if (rc < 0) {
qemuDomainRemoveInactive(driver, vm);
qemuProcessEndJob(driver, vm);
goto cleanup;
}
detail = VIR_DOMAIN_EVENT_STARTED_FROM_SNAPSHOT;
event = virDomainEventLifecycleNewFromObj(vm,
VIR_DOMAIN_EVENT_STARTED,
detail);
if (paused) {
detail = VIR_DOMAIN_EVENT_SUSPENDED_FROM_SNAPSHOT;
event2 = virDomainEventLifecycleNewFromObj(vm,
VIR_DOMAIN_EVENT_SUSPENDED,
detail);
}
}
break;
case VIR_DOMAIN_SNAPSHOT_PMSUSPENDED:
virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s",
_("qemu doesn't support reversion of snapshot taken in "
"PMSUSPENDED state"));
goto endjob;
case VIR_DOMAIN_SNAPSHOT_DISK_SNAPSHOT:
/* Rejected earlier as an external snapshot */
case VIR_DOMAIN_SNAPSHOT_NOSTATE:
case VIR_DOMAIN_SNAPSHOT_BLOCKED:
case VIR_DOMAIN_SNAPSHOT_LAST:
virReportError(VIR_ERR_INTERNAL_ERROR,
_("Invalid target domain state '%s'. Refusing "
"snapshot reversion"),
virDomainSnapshotStateTypeToString(snapdef->state));
goto endjob;
}
ret = 0;
endjob:
qemuProcessEndJob(driver, vm);
cleanup:
if (ret == 0) {
qemuSnapshotSetCurrent(vm, snap);
if (qemuDomainSnapshotWriteMetadata(vm, snap,
driver->xmlopt,
cfg->snapshotDir) < 0) {
virDomainSnapshotSetCurrent(vm->snapshots, NULL);
ret = -1;
}
}
if (ret == 0 && defined && vm->persistent &&
!(ret = virDomainDefSave(vm->newDef ? vm->newDef : vm->def,
driver->xmlopt, cfg->configDir))) {
detail = VIR_DOMAIN_EVENT_DEFINED_FROM_SNAPSHOT;
virObjectEventStateQueue(driver->domainEventState,
virDomainEventLifecycleNewFromObj(vm,
VIR_DOMAIN_EVENT_DEFINED,
detail));
}
virObjectEventStateQueue(driver->domainEventState, event);
virObjectEventStateQueue(driver->domainEventState, event2);
virCPUDefFree(origCPU);
virDomainDefFree(config);
virDomainDefFree(inactiveConfig);
return ret;
}
typedef struct _virQEMUMomentReparent virQEMUMomentReparent;
typedef virQEMUMomentReparent *virQEMUMomentReparentPtr;
struct _virQEMUMomentReparent {
const char *dir;
virDomainMomentObjPtr parent;
virDomainObjPtr vm;
virDomainXMLOptionPtr xmlopt;
int err;
int (*writeMetadata)(virDomainObjPtr, virDomainMomentObjPtr,
virDomainXMLOptionPtr, const char *);
};
static int
qemuSnapshotChildrenReparent(void *payload,
const char *name G_GNUC_UNUSED,
void *data)
{
virDomainMomentObjPtr moment = payload;
virQEMUMomentReparentPtr rep = data;
if (rep->err < 0)
return 0;
VIR_FREE(moment->def->parent_name);
if (rep->parent->def)
moment->def->parent_name = g_strdup(rep->parent->def->name);
rep->err = rep->writeMetadata(rep->vm, moment, rep->xmlopt,
rep->dir);
return 0;
}
int
qemuSnapshotDelete(virDomainObjPtr vm,
virDomainSnapshotPtr snapshot,
unsigned int flags)
{
virQEMUDriverPtr driver = snapshot->domain->conn->privateData;
int ret = -1;
virDomainMomentObjPtr snap = NULL;
virQEMUMomentRemove rem;
virQEMUMomentReparent rep;
bool metadata_only = !!(flags & VIR_DOMAIN_SNAPSHOT_DELETE_METADATA_ONLY);
int external = 0;
g_autoptr(virQEMUDriverConfig) cfg = virQEMUDriverGetConfig(driver);
virCheckFlags(VIR_DOMAIN_SNAPSHOT_DELETE_CHILDREN |
VIR_DOMAIN_SNAPSHOT_DELETE_METADATA_ONLY |
VIR_DOMAIN_SNAPSHOT_DELETE_CHILDREN_ONLY, -1);
if (qemuDomainObjBeginJob(driver, vm, QEMU_JOB_MODIFY) < 0)
return -1;
if (!(snap = qemuSnapObjFromSnapshot(vm, snapshot)))
goto endjob;
if (!metadata_only) {
if (!(flags & VIR_DOMAIN_SNAPSHOT_DELETE_CHILDREN_ONLY) &&
virDomainSnapshotIsExternal(snap))
external++;
if (flags & (VIR_DOMAIN_SNAPSHOT_DELETE_CHILDREN |
VIR_DOMAIN_SNAPSHOT_DELETE_CHILDREN_ONLY))
virDomainMomentForEachDescendant(snap,
qemuSnapshotCountExternal,
&external);
if (external) {
virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
_("deletion of %d external disk snapshots not "
"supported yet"), external);
goto endjob;
}
}
if (flags & (VIR_DOMAIN_SNAPSHOT_DELETE_CHILDREN |
VIR_DOMAIN_SNAPSHOT_DELETE_CHILDREN_ONLY)) {
rem.driver = driver;
rem.vm = vm;
rem.metadata_only = metadata_only;
rem.err = 0;
rem.current = virDomainSnapshotGetCurrent(vm->snapshots);
rem.found = false;
rem.momentDiscard = qemuDomainSnapshotDiscard;
virDomainMomentForEachDescendant(snap, qemuDomainMomentDiscardAll,
&rem);
if (rem.err < 0)
goto endjob;
if (rem.found) {
qemuSnapshotSetCurrent(vm, snap);
if (flags & VIR_DOMAIN_SNAPSHOT_DELETE_CHILDREN_ONLY) {
if (qemuDomainSnapshotWriteMetadata(vm, snap,
driver->xmlopt,
cfg->snapshotDir) < 0) {
virReportError(VIR_ERR_INTERNAL_ERROR,
_("failed to set snapshot '%s' as current"),
snap->def->name);
virDomainSnapshotSetCurrent(vm->snapshots, NULL);
goto endjob;
}
}
}
} else if (snap->nchildren) {
rep.dir = cfg->snapshotDir;
rep.parent = snap->parent;
rep.vm = vm;
rep.err = 0;
rep.xmlopt = driver->xmlopt;
rep.writeMetadata = qemuDomainSnapshotWriteMetadata;
virDomainMomentForEachChild(snap,
qemuSnapshotChildrenReparent,
&rep);
if (rep.err < 0)
goto endjob;
virDomainMomentMoveChildren(snap, snap->parent);
}
if (flags & VIR_DOMAIN_SNAPSHOT_DELETE_CHILDREN_ONLY) {
virDomainMomentDropChildren(snap);
ret = 0;
} else {
ret = qemuDomainSnapshotDiscard(driver, vm, snap, true, metadata_only);
}
endjob:
qemuDomainObjEndJob(driver, vm);
return ret;
}