blockdev-group-snapshot-sync accepts a list devices, filenames, and
formats.
It is attempted to keep the snapshot of the group atomic; if
any snapshot of a device in a given group fails, then the whole group
is reverted back to its original image, and error is reported.
This allows the group of disks to remain consistent with each other,
even across snapshot failures.
Signed-off-by: Jeff Cody<address@hidden>
---
blockdev.c | 130 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
qapi-schema.json | 45 +++++++++++++++++++
qmp-commands.hx | 39 ++++++++++++++++
3 files changed, 214 insertions(+), 0 deletions(-)
+
+error_rollback:
+ /* failure, undo everything as much as we can */
+ QSIMPLEQ_FOREACH(snap_entry,&gsnp_list, entry) {
+ if (snap_entry->has_pivoted) {
+ ret = bdrv_open(snap_entry->bs, snap_entry->old_filename,
+ snap_entry->flags, snap_entry->old_drv);
+ if (ret != 0) {
+ /* This is very very bad */
+ error_set(errp, QERR_OPEN_FILE_FAILED,
+ snap_entry->old_filename);
Is there any way to reduce the likelihood of a rollback failure?
+SQMP
+blockdev-group-snapshot-sync
+----------------------
+
+Synchronous snapshot of one or more block devices. A list array input
+is accepted, that contains the device, snapshot-file to be create as the
+target of the new image. If the file exists, or if it is a device, the
+snapshot will be created in the existing file/device. If does not
+exist, a new file will be created. format specifies the format of the
+snapshot image, default is qcow2. On failure of any device, it is
+attempted to reopen the original image for all the devices that were
+specified.
+
+Arguments:
+
+- "device": device name to snapshot (json-string)
+- "snapshot-file": name of new image file (json-string)
+- "format": format of new image (json-string, optional)
Shouldn't this mention that the arguments is a JSON list, rather than a
single argument?
+
+Example:
+
+-> { "execute": "blockdev-group-snapshot-sync", "arguments": [{ "device":
"ide-hd0",
+
"snapshot-file":
+
"/some/place/my-image",
+ "format":
"qcow2" },
+ { "device":
"ide-hd1",
+
"snapshot-file":
+
"/some/place/my-image2",
+ "format":
"qcow2" } }
Are you missing a ']' before the final '}' here?