Fabiano Rosas <faro...@suse.de> writes:
> The MigrationState is a QOM object with TYPE_DEVICE as a parent. This
> was done about eight years ago so the migration code could make use of
> qdev properties to define the defaults for the migration parameters
> and to be able to expose migration knobs for debugging via the
> '-global migration' command line option.
>
> Due to unrelated historical reasons, three of the migration parameters
> (TLS options) received different types when used via the
> query-migrate-parameters QMP command than with the
> migrate-set-parameters command. This has created a lot of duplication
> in the migration code and in the QAPI documentation because the whole
> of MigrationParameters had to be duplicated as well.
>
> The migration code is now being fixed to remove the duplication and
> for that to happen the offending fields need to be reconciled into a
> single type. The StrOrNull type is going to be used.
>
> To keep the command line compatibility, the parameters need to
> continue being exposed via qdev properties accessible from the command
> line. Introduce a qdev property StrOrNull just for that.
>
> Note that this code is being kept in migration/options.c because this
> version of StrOrNull doesn't need to handle QNULL because it was never
> a valid option in the previous command line, which took a string.
>
> Signed-off-by: Fabiano Rosas <faro...@suse.de>
> ---
> migration/options.c | 47 +++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 47 insertions(+)
>
> diff --git a/migration/options.c b/migration/options.c
> index 162c72cda4..384ef9e421 100644
> --- a/migration/options.c
> +++ b/migration/options.c
> @@ -83,6 +83,11 @@
> #define DEFINE_PROP_MIG_CAP(name, x) \
> DEFINE_PROP_BOOL(name, MigrationState, capabilities[x], false)
>
> +const PropertyInfo qdev_prop_StrOrNull;
> +#define DEFINE_PROP_STR_OR_NULL(_name, _state, _field) \
> + DEFINE_PROP(_name, _state, _field, qdev_prop_StrOrNull, StrOrNull *, \
> + .set_default = true)
> +
> #define DEFAULT_MIGRATE_VCPU_DIRTY_LIMIT_PERIOD 1000 /* milliseconds
> */
> #define DEFAULT_MIGRATE_VCPU_DIRTY_LIMIT 1 /* MB/s */
>
> @@ -204,6 +209,48 @@ const Property migration_properties[] = {
> };
> const size_t migration_properties_count = ARRAY_SIZE(migration_properties);
>
> +/*
> + * qdev property for TLS options handling via '-global migration'
> + * command line.
> + */
Looks like this was a function comment. It's not, it applies to the
PropertyInfo and its method. Move it to the PropertyInfo?
Maybe
/*
* String property like qdev_prop_string, except it's backed by a
* StrOrNull * instead of a char *. This is intended for
* TYPE_MIGRATION's TLS options.
*/
> +static void set_StrOrNull(Object *obj, Visitor *v, const char *name,
> + void *opaque, Error **errp)
> +{
> + const Property *prop = opaque;
> + StrOrNull **ptr = object_field_prop_ptr(obj, prop);
> + StrOrNull *str_or_null = g_new0(StrOrNull, 1);
> +
> + /*
> + * Only str to keep compatibility, QNULL was never used via
> + * command line.
> + */
> + str_or_null->type = QTYPE_QSTRING;
> + if (!visit_type_str(v, name, &str_or_null->u.s, errp)) {
> + return;
> + }
> +
> + qapi_free_StrOrNull(*ptr);
> + *ptr = str_or_null;
> +}
> +
> +static void release_StrOrNull(Object *obj, const char *name, void *opaque)
> +{
> + const Property *prop = opaque;
> + qapi_free_StrOrNull(*(StrOrNull **)object_field_prop_ptr(obj, prop));
> +}
> +
> +static void set_default_value_tls_opt(ObjectProperty *op, const Property
> *prop)
> +{
> + object_property_set_default_str(op, "");
> +}
> +
> +const PropertyInfo qdev_prop_StrOrNull = {
> + .type = "StrOrNull",
> + .set = set_StrOrNull,
> + .release = release_StrOrNull,
> + .set_default_value = set_default_value_tls_opt,
> +};
No getter, i.e. properties will be write-only. This is unusual. Is it
safe?
> +
> bool migrate_auto_converge(void)
> {
> MigrationState *s = migrate_get_current();
