On Tue, 19 Jan 2021 13:35:35 +0100 Michal Privoznik <mpriv...@redhat.com> wrote:
> When management applications (like Libvirt) want to check whether > memory-backend-file.pmem is supported they can list object > properties using 'qom-list-properties'. However, 'pmem' is > declared always (and thus reported always) and only at runtime > QEMU errors out if it was built without libpmem (and thus can not > guarantee write persistence). This is suboptimal since we have > ability to declare attributes at compile time. > > Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1915216 > Signed-off-by: Michal Privoznik <mpriv...@redhat.com> Reviewed-by: Igor Mammedov <imamm...@redhat.com> > --- > backends/hostmem-file.c | 13 ++++--------- > 1 file changed, 4 insertions(+), 9 deletions(-) > > diff --git a/backends/hostmem-file.c b/backends/hostmem-file.c > index 40e1e5b3e3..7e30eb5985 100644 > --- a/backends/hostmem-file.c > +++ b/backends/hostmem-file.c > @@ -123,6 +123,7 @@ static void file_memory_backend_set_align(Object *o, > Visitor *v, > fb->align = val; > } > > +#ifdef CONFIG_LIBPMEM > static bool file_memory_backend_get_pmem(Object *o, Error **errp) > { > return MEMORY_BACKEND_FILE(o)->is_pmem; > @@ -139,17 +140,9 @@ static void file_memory_backend_set_pmem(Object *o, bool > value, Error **errp) > return; > } > > -#ifndef CONFIG_LIBPMEM > - if (value) { > - error_setg(errp, "Lack of libpmem support while setting the > 'pmem=on'" > - " of %s. We can't ensure data persistence.", > - object_get_typename(o)); > - return; > - } > -#endif > - > fb->is_pmem = value; > } > +#endif /* CONFIG_LIBPMEM */ > > static void file_backend_unparent(Object *obj) > { > @@ -180,8 +173,10 @@ file_backend_class_init(ObjectClass *oc, void *data) > file_memory_backend_get_align, > file_memory_backend_set_align, > NULL, NULL); > +#ifdef CONFIG_LIBPMEM > object_class_property_add_bool(oc, "pmem", > file_memory_backend_get_pmem, file_memory_backend_set_pmem); > +#endif > } > > static void file_backend_instance_finalize(Object *o)
