vhost-user: simplify vhost_user_init/vhost_user_cleanup

Take a VhostUserState* that can be pre-allocated, and initialize it
with the associated chardev.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Tiwei Bie <tiwei.bie@intel.com>
Message-Id: <20190308140454.32437-4-marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
diff --git a/backends/cryptodev-vhost-user.c b/backends/cryptodev-vhost-user.c
index d539f14..1052a5d 100644
--- a/backends/cryptodev-vhost-user.c
+++ b/backends/cryptodev-vhost-user.c
@@ -47,7 +47,7 @@
 typedef struct CryptoDevBackendVhostUser {
     CryptoDevBackend parent_obj;
 
-    VhostUserState *vhost_user;
+    VhostUserState vhost_user;
     CharBackend chr;
     char *chr_name;
     bool opened;
@@ -104,7 +104,7 @@
             continue;
         }
 
-        options.opaque = s->vhost_user;
+        options.opaque = &s->vhost_user;
         options.backend_type = VHOST_BACKEND_TYPE_USER;
         options.cc = b->conf.peers.ccs[i];
         s->vhost_crypto[i] = cryptodev_vhost_init(&options);
@@ -182,7 +182,6 @@
     size_t i;
     Error *local_err = NULL;
     Chardev *chr;
-    VhostUserState *user;
     CryptoDevBackendClient *cc;
     CryptoDevBackendVhostUser *s =
                       CRYPTODEV_BACKEND_VHOST_USER(backend);
@@ -213,15 +212,10 @@
         }
     }
 
-    user = vhost_user_init();
-    if (!user) {
-        error_setg(errp, "Failed to init vhost_user");
+    if (!vhost_user_init(&s->vhost_user, &s->chr, errp)) {
         return;
     }
 
-    user->chr = &s->chr;
-    s->vhost_user = user;
-
     qemu_chr_fe_set_handlers(&s->chr, NULL, NULL,
                      cryptodev_vhost_user_event, NULL, s, NULL, true);
 
@@ -307,11 +301,7 @@
         }
     }
 
-    if (s->vhost_user) {
-        vhost_user_cleanup(s->vhost_user);
-        g_free(s->vhost_user);
-        s->vhost_user = NULL;
-    }
+    vhost_user_cleanup(&s->vhost_user);
 }
 
 static void cryptodev_vhost_user_set_chardev(Object *obj,