Patch no longer applies.
Pavel Hrdina <phrd...@redhat.com> writes:
> QMP command "vm-snapshot-save" has also extra optional force parameter
> to specify whether replace existing snapshot or not. It also returns
> information about created snapshot.
Took me a minute to realize that you're comparing it to HMP command
savevm.
> Signed-off-by: Pavel Hrdina <phrd...@redhat.com>
> ---
> hmp-commands.hx | 4 ++--
> hmp.c | 11 +++++++++
> hmp.h | 1 +
> include/sysemu/sysemu.h | 1 -
> qapi-schema.json | 22 ++++++++++++++++++
> qmp-commands.hx | 43 ++++++++++++++++++++++++++++++++++
> savevm.c | 62
> +++++++++++++++++++++++++++++++------------------
> 7 files changed, 118 insertions(+), 26 deletions(-)
>
> diff --git a/hmp-commands.hx b/hmp-commands.hx
> index 3d98604..382b87d 100644
> --- a/hmp-commands.hx
> +++ b/hmp-commands.hx
> @@ -310,7 +310,7 @@ ETEXI
> .args_type = "name:s?",
> .params = "[tag|id]",
> .help = "save a VM snapshot. If no tag or id are provided, a
> new snapshot is created",
> - .mhandler.cmd = do_savevm,
> + .mhandler.cmd = hmp_vm_snapshot_save,
> },
>
> STEXI
> @@ -318,7 +318,7 @@ STEXI
> @findex savevm
> Create a snapshot of the whole virtual machine. If @var{tag} is
> provided, it is used as human readable identifier. If there is already
> -a snapshot with the same tag or ID, it is replaced. More info at
> +a snapshot with the same @var{tag} or @var{id}, it is replaced. More info at
> @ref{vm_snapshots}.
> ETEXI
>
Markup fix squashed in. Acceptable, because it's really minor.
> diff --git a/hmp.c b/hmp.c
> index dbe9b90..b38b6ce 100644
> --- a/hmp.c
> +++ b/hmp.c
> @@ -1433,3 +1433,14 @@ void hmp_chardev_remove(Monitor *mon, const QDict
> *qdict)
> qmp_chardev_remove(qdict_get_str(qdict, "id"), &local_err);
> hmp_handle_error(mon, &local_err);
> }
> +
> +void hmp_vm_snapshot_save(Monitor *mon, const QDict *qdict)
> +{
> + const char *name = qdict_get_try_str(qdict, "name");
> + Error *err = NULL;
> + SnapshotInfo *info = NULL;
> +
> + info = qmp_vm_snapshot_save(!!name, name, true, true, &err);
> + qapi_free_SnapshotInfo(info);
> + hmp_handle_error(mon, &err);
> +}
> diff --git a/hmp.h b/hmp.h
> index 80e8b41..1bb8590 100644
> --- a/hmp.h
> +++ b/hmp.h
> @@ -86,5 +86,6 @@ void hmp_nbd_server_add(Monitor *mon, const QDict *qdict);
> void hmp_nbd_server_stop(Monitor *mon, const QDict *qdict);
> void hmp_chardev_add(Monitor *mon, const QDict *qdict);
> void hmp_chardev_remove(Monitor *mon, const QDict *qdict);
> +void hmp_vm_snapshot_save(Monitor *mon, const QDict *qdict);
>
> #endif
> diff --git a/include/sysemu/sysemu.h b/include/sysemu/sysemu.h
> index 9e6a4a9..87b82d7 100644
> --- a/include/sysemu/sysemu.h
> +++ b/include/sysemu/sysemu.h
> @@ -65,7 +65,6 @@ void qemu_remove_exit_notifier(Notifier *notify);
>
> void qemu_add_machine_init_done_notifier(Notifier *notify);
>
> -void do_savevm(Monitor *mon, const QDict *qdict);
> int load_vmstate(const char *name);
> void do_delvm(Monitor *mon, const QDict *qdict);
> void do_info_snapshots(Monitor *mon, const QDict *qdict);
> diff --git a/qapi-schema.json b/qapi-schema.json
> index f629a24..cbb73d9 100644
> --- a/qapi-schema.json
> +++ b/qapi-schema.json
> @@ -3453,3 +3453,25 @@
> # Since: 1.5
> ##
> { 'command': 'query-tpm', 'returns': ['TPMInfo'] }
> +
> +##
> +# @vm-snapshot-save:
> +#
> +# Create a snapshot of the whole virtual machine. If tag is provided as
> @name,
> +# it is used as human readable identifier. If there is already a snapshot
> +# with the same tag or id, the force argument needs to be true to replace it.
"tag or id"?
HMP command savevm's argument is matched against both QEMUSnapshotInfo
member id_str (a.k.a. id) and name (a.k.a. tag). Do we really want that
kind of overloading in QMP? Shouldn't we make it tag vs. id explicit
there?
> +#
> +# The VM is automatically stopped and resumed and saving a snapshot can take
> +# a long time.
> +#
> +# @name: #optional tag of new snapshot or tag|id of existing snapshot
Should we make this mandatory? We have to keep the argument optional in
HMP, but that needn't concern us here.
> +#
> +# @force: #optional specify whether existing snapshot is replaced or not,
> +# default is false
> +#
> +# Returns: SnapshotInfo on success
> +#
> +# Since: 1.5
> +##
> +{ 'command': 'vm-snapshot-save', 'data': {'*name': 'str', '*force': 'bool'},
> + 'returns': 'SnapshotInfo' }
> diff --git a/qmp-commands.hx b/qmp-commands.hx
> index 1e0e11e..119e7a5 100644
> --- a/qmp-commands.hx
> +++ b/qmp-commands.hx
> @@ -1445,6 +1445,49 @@ Example:
>
> EQMP
> {
> + .name = "vm-snapshot-save",
> + .args_type = "name:s?,force:b?",
> + .params = "[name] [force]",
> + .help = "save a VM snapshot, to replace existing snapshot use
> force parameter",
> + .mhandler.cmd_new = qmp_marshal_input_vm_snapshot_save
> + },
> +
> +SQMP
> +vm-snapshot-save
> +------
> +
> +Create a snapshot of the whole virtual machine. If tag is provided as name,
> +it is used as human readable identifier. If there is already a snapshot with
> +the same tag, the force argument needs to be true to replace it.
> +
> +The VM is automatically stopped and resumed and saving a snapshot can take
> +a long time.
> +
> +Arguments:
> +
> +- "name": tag of new snapshot or tag|id of existing snapshot
> + (json-string, optional)
> +
> +- "force": specify whether existing snapshot is replaced or not,
> + default is false (json-bool, optional)
> +
> +Example:
> +
> +-> { "execute": "vm-snapshot-save", "arguments": { "name": "my_snapshot" } }
> +<- {
> + "return": {
> + "id": "1",
> + "name": "my_snapshot",
> + "date-sec": 1364480534,
> + "date-nsec": 978215000,
> + "vm-clock-sec": 5,
> + "vm-clock-nsec": 153620449,
> + "vm-state-size": 5709953
> + }
> + }
> +
> +EQMP
> + {
> .name = "qmp_capabilities",
> .args_type = "",
> .params = "",
> diff --git a/savevm.c b/savevm.c
> index 3c1ac9e..7b127eb 100644
> --- a/savevm.c
> +++ b/savevm.c
> @@ -2249,17 +2249,18 @@ static int del_existing_snapshots(const char *name,
> Error **errp)
> return 0;
> }
>
> -void do_savevm(Monitor *mon, const QDict *qdict)
> +SnapshotInfo *qmp_vm_snapshot_save(bool has_name, const char *name,
> + bool has_force, bool force, Error **errp)
> {
> BlockDriverState *bs, *bs1;
> QEMUSnapshotInfo sn1, *sn = &sn1, old_sn1, *old_sn = &old_sn1;
> + SnapshotInfo *info = NULL;
> int ret;
> QEMUFile *f;
> int saved_vm_running;
> uint64_t vm_state_size;
> qemu_timeval tv;
> struct tm tm;
> - const char *name = qdict_get_try_str(qdict, "name");
> Error *local_err = NULL;
>
> /* Verify if there is a device that doesn't support snapshots and is
> writable */
> @@ -2271,16 +2272,16 @@ void do_savevm(Monitor *mon, const QDict *qdict)
> }
>
> if (!bdrv_can_snapshot(bs)) {
> - monitor_printf(mon, "Device '%s' is writable but does not
> support snapshots.\n",
> - bdrv_get_device_name(bs));
> - return;
> + error_setg(errp, "device '%s' is writable but does not support "
> + "snapshots", bdrv_get_device_name(bs));
> + return NULL;
Any particular reason for de-capitalizing "Device"? More of the same below.
> }
> }
>
> bs = bdrv_snapshots();
> if (!bs) {
> - monitor_printf(mon, "No block device can accept snapshots\n");
> - return;
> + error_setg(errp, "no block device can accept snapshots");
> + return NULL;
> }
>
> saved_vm_running = runstate_is_running();
> @@ -2294,11 +2295,23 @@ void do_savevm(Monitor *mon, const QDict *qdict)
> sn->date_nsec = tv.tv_usec * 1000;
> sn->vm_clock_nsec = qemu_get_clock_ns(vm_clock);
>
> - if (name) {
> + if (has_name) {
> ret = bdrv_snapshot_find(bs, old_sn, name);
> if (ret >= 0) {
> - pstrcpy(sn->name, sizeof(sn->name), old_sn->name);
> - pstrcpy(sn->id_str, sizeof(sn->id_str), old_sn->id_str);
> + if (has_force && force) {
> + pstrcpy(sn->name, sizeof(sn->name), old_sn->name);
> + pstrcpy(sn->id_str, sizeof(sn->id_str), old_sn->id_str);
> +
> + /* Delete old snapshots of the same name */
> + if (del_existing_snapshots(name, &local_err) < 0) {
> + error_propagate(errp, local_err);
> + goto the_end;
> + }
> + } else {
> + error_setg(errp, "snapshot '%s' exists, for override use "
> + "'force' parameter", name);
> + goto the_end;
> + }
> } else {
> pstrcpy(sn->name, sizeof(sn->name), name);
> }
} else {
/* cast below needed for OpenBSD where tv_sec is still 'long' */
localtime_r((const time_t *)&tv.tv_sec, &tm);
> @@ -2308,24 +2321,17 @@ void do_savevm(Monitor *mon, const QDict *qdict)
> strftime(sn->name, sizeof(sn->name), "vm-%Y%m%d%H%M%S", &tm);
Interestingly, we do not check whether this auto-generated name already
exists. Not your fault, but could use fixing.
> }
>
> - /* Delete old snapshots of the same name */
> - if (name && del_existing_snapshots(name, &local_err) < 0) {
> - monitor_printf(mon, "%s\n", error_get_pretty(local_err));
> - error_free(local_err);
> - goto the_end;
> - }
> -
Your code motion adds two conditions for calling
del_existing_snapshots():
1. has_force && force: feature. I guess I'd add the feature in a
separate patch, to keep this one as simple as possible. Your choice.
2. bdrv_snapshot_find() succeeds. Care to explain why this one's
correct?
> /* save the VM state */
> f = qemu_fopen_bdrv(bs, 1);
> if (!f) {
> - monitor_printf(mon, "Could not open VM state file\n");
> + error_setg(errp, "failed to open '%s' file",
> bdrv_get_device_name(bs));
> goto the_end;
> }
> - ret = qemu_savevm_state(f, NULL);
> + ret = qemu_savevm_state(f, &local_err);
> vm_state_size = qemu_ftell(f);
> qemu_fclose(f);
> if (ret < 0) {
> - monitor_printf(mon, "Error %d while writing VM\n", ret);
> + error_propagate(errp, local_err);
> goto the_end;
> }
>
> @@ -2336,17 +2342,27 @@ void do_savevm(Monitor *mon, const QDict *qdict)
> if (bdrv_can_snapshot(bs1)) {
> /* Write VM state size only to the image that contains the state
> */
> sn->vm_state_size = (bs == bs1 ? vm_state_size : 0);
> - ret = bdrv_snapshot_create(bs1, sn, NULL);
> + ret = bdrv_snapshot_create(bs1, sn, &local_err);
> if (ret < 0) {
> - monitor_printf(mon, "Error while creating snapshot on
> '%s'\n",
> - bdrv_get_device_name(bs1));
> + error_propagate(errp, local_err);
When we go through this failure...
> }
> }
> }
>
> + info = g_malloc0(sizeof(SnapshotInfo));
> + info->id = g_strdup(sn->id_str);
> + info->name = g_strdup(sn->name);
> + info->date_nsec = sn->date_nsec;
> + info->date_sec = sn->date_sec;
> + info->vm_state_size = vm_state_size;
> + info->vm_clock_nsec = sn->vm_clock_nsec % 1000000000;
> + info->vm_clock_sec = sn->vm_clock_nsec / 1000000000;
> +
> the_end:
> if (saved_vm_running)
> vm_start();
> +
> + return info;
... we return both info and an Error. Stupid question: is that okay?
> }
>
> void qmp_xen_save_devices_state(const char *filename, Error **errp)
