From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58356) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YbEUb-0008Jz-J8 for qemu-devel@nongnu.org; Thu, 26 Mar 2015 16:35:06 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YbEUX-0003Fh-GD for qemu-devel@nongnu.org; Thu, 26 Mar 2015 16:35:05 -0400 Received: from mail-wi0-x22a.google.com ([2a00:1450:400c:c05::22a]:37237) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YbEUX-0003FV-A4 for qemu-devel@nongnu.org; Thu, 26 Mar 2015 16:35:01 -0400 Received: by wiaa2 with SMTP id a2so4118070wia.0 for ; Thu, 26 Mar 2015 13:34:59 -0700 (PDT) Sender: Paolo Bonzini Message-ID: <55146D6F.3020109@redhat.com> Date: Thu, 26 Mar 2015 21:34:55 +0100 From: Paolo Bonzini MIME-Version: 1.0 References: <1427389626-23487-1-git-send-email-lma@suse.com> <1427389626-23487-2-git-send-email-lma@suse.com> In-Reply-To: <1427389626-23487-2-git-send-email-lma@suse.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v3 1/2] qom: Add can_be_deleted callback to UserCreatableClass List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Lin Ma , imammedo@redhat.com, afaerber@suse.de, peter.crosthwaite@xilinx.com Cc: qemu-devel@nongnu.org On 26/03/2015 18:07, Lin Ma wrote: > If backends implement the can_be_deleted and it returns false, > Then the qmp_object_del won't delete the given backends. > > Signed-off-by: Lin Ma > --- > include/qom/object_interfaces.h | 3 +++ > qmp.c | 13 +++++++++++++ > 2 files changed, 16 insertions(+) > > diff --git a/include/qom/object_interfaces.h b/include/qom/object_interfaces.h > index b792283..19b66f1 100644 > --- a/include/qom/object_interfaces.h > +++ b/include/qom/object_interfaces.h > @@ -25,6 +25,8 @@ typedef struct UserCreatable { > * UserCreatableClass: > * @parent_class: the base class > * @complete: callback to be called after @obj's properties are set. > + * @can_be_deleted: callback to be called before an object is removed > + * to check if @obj can be removed safely. > * > * Interface is designed to work with -object/object-add/object_add > * commands. > @@ -47,6 +49,7 @@ typedef struct UserCreatableClass { > > /* */ > void (*complete)(UserCreatable *uc, Error **errp); > + bool (*can_be_deleted)(UserCreatable *uc, Error **errp); > } UserCreatableClass; > > /** > diff --git a/qmp.c b/qmp.c > index c479e77..a9156d6 100644 > --- a/qmp.c > +++ b/qmp.c > @@ -711,6 +711,19 @@ void qmp_object_del(const char *id, Error **errp) > error_setg(errp, "object id not found"); > return; > } > + > + UserCreatableClass *ucc; > + UserCreatable *uc = > + (UserCreatable *)object_dynamic_cast(obj, TYPE_USER_CREATABLE); > + ucc = USER_CREATABLE_GET_CLASS(uc); > + if (ucc->can_be_deleted) { > + if (!ucc->can_be_deleted(uc, errp)) { Please add a function user_creatable_can_be_deleted(UserCreatable *uc) that does the call (and returns true if the field is NULL. > + char *path = object_get_canonical_path_component(obj); > + error_setg(errp, "%s is in used, can not be deleted", path); You can use id directly, no need to call object_get_canonical_path_component. > + g_free(path); > + return; > + } Thanks, Paolo > + } > object_unparent(obj); > } > >