hmp: use snapshot name to determine whether a snapshot is 'fully available'

Currently qemu uses snapshot id to determine whether a snapshot is fully
available, It causes incorrect output in some scenario.

For instance:
(qemu) info block
drive_image1 (#block113): /opt/vms/SLES12-SP1-JeOS-x86_64-GM/disk0.qcow2
(qcow2)
    Cache mode:       writeback

drive_image2 (#block349): /opt/vms/SLES12-SP1-JeOS-x86_64-GM/disk1.qcow2
(qcow2)
    Cache mode:       writeback
(qemu)
(qemu) info snapshots
There is no snapshot available.
(qemu)
(qemu) snapshot_blkdev_internal drive_image1 snap1
(qemu)
(qemu) info snapshots
There is no suitable snapshot available
(qemu)
(qemu) savevm checkpoint-1
(qemu)
(qemu) info snapshots
ID        TAG                 VM SIZE                DATE       VM CLOCK
1         snap1                     0 2016-05-22 16:57:31   00:01:30.567
(qemu)

$ qemu-img snapshot -l disk0.qcow2
Snapshot list:
ID        TAG                 VM SIZE                DATE       VM CLOCK
1         snap1                     0 2016-05-22 16:57:31   00:01:30.567
2         checkpoint-1           165M 2016-05-22 16:58:07   00:02:06.813

$ qemu-img snapshot -l disk1.qcow2
Snapshot list:
ID        TAG                 VM SIZE                DATE       VM CLOCK
1         checkpoint-1              0 2016-05-22 16:58:07   00:02:06.813

The patch uses snapshot name instead of snapshot id to determine whether a
snapshot is fully available and uses '--' instead of snapshot id in output
because the snapshot id is not guaranteed to be the same on all images.
For instance:
(qemu) info snapshots
List of snapshots present on all disks:
 ID        TAG                 VM SIZE                DATE       VM CLOCK
 --        checkpoint-1           165M 2016-05-22 16:58:07   00:02:06.813

Signed-off-by: Lin Ma <lma@suse.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1467869164-26688-2-git-send-email-lma@suse.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This commit is contained in:
Lin Ma 2016-07-07 13:26:03 +08:00 committed by Max Reitz
parent 435d5ee6cd
commit 3a1ee71190

View File

@ -2230,7 +2230,7 @@ void hmp_info_snapshots(Monitor *mon, const QDict *qdict)
available_snapshots = g_new0(int, nb_sns);
total = 0;
for (i = 0; i < nb_sns; i++) {
if (bdrv_all_find_snapshot(sn_tab[i].id_str, &bs1) == 0) {
if (bdrv_all_find_snapshot(sn_tab[i].name, &bs1) == 0) {
available_snapshots[total] = i;
total++;
}
@ -2241,6 +2241,10 @@ void hmp_info_snapshots(Monitor *mon, const QDict *qdict)
monitor_printf(mon, "\n");
for (i = 0; i < total; i++) {
sn = &sn_tab[available_snapshots[i]];
/* The ID is not guaranteed to be the same on all images, so
* overwrite it.
*/
pstrcpy(sn->id_str, sizeof(sn->id_str), "--");
bdrv_snapshot_dump((fprintf_function)monitor_printf, mon, sn);
monitor_printf(mon, "\n");
}