snapshot: detect when qemu lacks disk-snapshot support

Noticed when testing new libvirt against old qemu that lacked the
snapshot_blkdev HMP command.  Libvirt was mistakenly treating the
command as successful, and re-writing the domain XML to use the
just-created 0-byte file, rendering the domain broken on restart.

* src/qemu/qemu_monitor_text.c (qemuMonitorTextDiskSnapshot):
Notice another possible error message.
* src/qemu/qemu_driver.c
(qemuDomainSnapshotCreateSingleDiskActive): Don't keep 0-byte file
on failure.
This commit is contained in:
Eric Blake 2011-10-18 15:28:47 -06:00
parent 94f776e716
commit dad15a2e02
2 changed files with 3 additions and 2 deletions

View File

@ -9027,7 +9027,6 @@ qemuDomainSnapshotCreateSingleDiskActive(struct qemud_driver *driver,
VIR_WARN("Unable to release lock on %s", source);
goto cleanup;
}
need_unlink = false;
disk->src = origsrc;
origsrc = NULL;
@ -9041,6 +9040,7 @@ qemuDomainSnapshotCreateSingleDiskActive(struct qemud_driver *driver,
goto cleanup;
/* Update vm in place to match changes. */
need_unlink = false;
VIR_FREE(disk->src);
disk->src = source;
source = NULL;

View File

@ -3064,7 +3064,8 @@ qemuMonitorTextDiskSnapshot(qemuMonitorPtr mon, const char *device,
goto cleanup;
}
if (strstr(reply, "error while creating qcow2") != NULL) {
if (strstr(reply, "error while creating qcow2") != NULL ||
strstr(reply, "unknown command:") != NULL) {
qemuReportError(VIR_ERR_OPERATION_FAILED,
_("Failed to take snapshot: %s"), reply);
goto cleanup;