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libvirt/src/qemu/qemu_snapshot.c
Peter Krempa 926563dc3a qemuDomainSnapshotForEachQcow2: Pass in 'def' rather than selecting it internally 
In some cases such as when creating an internal inactive snapshot we
know that the domain definition in the snapshot is equivalent to the
current definition. Additionally we set up the current definition for
the snapshotting but not the one contained in the snapshot. Thus in some
cases the caller knows better which def to use.

Make qemuDomainSnapshotForEachQcow2 take the definition by the caller
and copy the logic for selecting the definition to callers where we
don't know for sure that the above claim applies.

This fixes internal inactive snapshots when <disk type='volume'> is used
as we translate the pool/vol combo only in the current def.

Resolves: https://gitlab.com/libvirt/libvirt/-/issues/97
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2020-11-24 17:59:26 +01:00

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/*
* 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
* <http://www.gnu.org/licenses/>.
*/
#include <config.h>
#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 "virstring.h"
#include "virdomainsnapshotobjlist.h"
#include "virqemu.h"
#define VIR_FROM_THIS VIR_FROM_QEMU
VIR_LOG_INIT("qemu.qemu_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;
}
/* Return -1 if request is not sent to agent due to misconfig, -2 if request
* is sent but failed, and number of frozen filesystems on success. If -2 is
* returned, FSThaw should be called revert the quiesced status. */
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 < 0 ? -2 : 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_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_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_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_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_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 (virStorageFileInit(snapdisk->src) < 0)
return -1;
rc = virStorageFileStat(snapdisk->src, &st);
err = errno;
virStorageFileDeinit(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_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_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 (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 &&
virStorageFileUnlink(data[i].src) < 0) {
VIR_WARN("Unable to remove just-created %s",
NULLSTR(data[i].src->path));
}
if (data[i].initialized)
virStorageFileDeinit(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 = virStorageFileSupportsCreate(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 &&
virStorageFileSupportsBackingChainTraversal(dd->src))
updateRelativeBacking = true;
if (supportsCreate || updateRelativeBacking) {
if (qemuDomainStorageFileInit(driver, vm, dd->src, NULL) < 0)
return -1;
dd->initialized = true;
if (reuse) {
if (updateRelativeBacking) {
g_autofree char *backingStoreStr = NULL;
if (virStorageFileGetBackingStoreStr(dd->src, &backingStoreStr) < 0)
return -1;
if (backingStoreStr != NULL) {
if (virStorageIsRelative(backingStoreStr))
dd->relPath = g_steal_pointer(&backingStoreStr);
}
}
} 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 (virStorageFileCreate(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)
virStorageFileDeinit(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 <transient/>. Note
* that the validation code ensures that <transient> 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;
int thaw = 0; /* 1 if freeze succeeded, -1 if freeze failed */
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 freeze;
if (qemuDomainObjBeginAgentJob(driver, vm, QEMU_AGENT_JOB_MODIFY) < 0)
goto cleanup;
if (virDomainObjCheckActive(vm) < 0) {
qemuDomainObjEndAgentJob(vm);
goto cleanup;
}
freeze = qemuSnapshotFSFreeze(vm, NULL, 0);
qemuDomainObjEndAgentJob(vm);
if (freeze < 0) {
/* the helper reported the error */
if (freeze == -2)
thaw = -1; /* the command is sent but agent failed */
goto cleanup;
}
thaw = 1;
}
/* 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 = 0;
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 != 0 &&
qemuDomainObjBeginAgentJob(driver, vm, QEMU_AGENT_JOB_MODIFY) >= 0 &&
virDomainObjIsActive(vm)) {
if (qemuSnapshotFSThaw(vm, ret == 0 && thaw > 0) < 0) {
/* helper reported the error, if it was needed */
if (thaw > 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)
virDomainSnapshotSetCurrent(vm->snapshots, 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) {
virDomainSnapshotSetCurrent(vm->snapshots, 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) {
virDomainSnapshotSetCurrent(vm->snapshots, 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;
}
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