vhost-user-blk: Factor out vhost_user_blk_realize_connect()

This function is the part that we will want to retry if the connection
is lost during initialisation, so factor it out to keep the following
patch simpler.

The error path for vhost_dev_get_config() forgot disconnecting the
chardev, add this while touching the code.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20210609154658.350308-7-kwolf@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

hw/block/vhost-user-blk.c

@@ -423,6 +423,36 @@ static void vhost_user_blk_event(void *opaque, QEMUChrEvent event)
     }
 }
 
+static int vhost_user_blk_realize_connect(VHostUserBlk *s, Error **errp)
+{
+    DeviceState *dev = &s->parent_obj.parent_obj;
+    int ret;
+
+    s->connected = false;
+
+    ret = qemu_chr_fe_wait_connected(&s->chardev, errp);
+    if (ret < 0) {
+        return ret;
+    }
+
+    ret = vhost_user_blk_connect(dev, errp);
+    if (ret < 0) {
+        qemu_chr_fe_disconnect(&s->chardev);
+        return ret;
+    }
+    assert(s->connected);
+
+    ret = vhost_dev_get_config(&s->dev, (uint8_t *)&s->blkcfg,
+                               sizeof(struct virtio_blk_config), errp);
+    if (ret < 0) {
+        qemu_chr_fe_disconnect(&s->chardev);
+        vhost_dev_cleanup(&s->dev);
+        return ret;
+    }
+
+    return 0;
+}
+
 static void vhost_user_blk_device_realize(DeviceState *dev, Error **errp)
 {
     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
@@ -467,22 +497,10 @@ static void vhost_user_blk_device_realize(DeviceState *dev, Error **errp)
 
     s->inflight = g_new0(struct vhost_inflight, 1);
     s->vhost_vqs = g_new0(struct vhost_virtqueue, s->num_queues);
-    s->connected = false;
-
-    if (qemu_chr_fe_wait_connected(&s->chardev, errp) < 0) {
-        goto virtio_err;
-    }
 
-    if (vhost_user_blk_connect(dev, errp) < 0) {
-        qemu_chr_fe_disconnect(&s->chardev);
-        goto virtio_err;
-    }
-    assert(s->connected);
-
-    ret = vhost_dev_get_config(&s->dev, (uint8_t *)&s->blkcfg,
-                               sizeof(struct virtio_blk_config), errp);
+    ret = vhost_user_blk_realize_connect(s, errp);
     if (ret < 0) {
-        goto vhost_err;
+        goto virtio_err;
     }
 
     /* we're fully initialized, now we can operate, so add the handler */
@@ -491,8 +509,6 @@ static void vhost_user_blk_device_realize(DeviceState *dev, Error **errp)
                              NULL, true);
     return;
 
-vhost_err:
-    vhost_dev_cleanup(&s->dev);
 virtio_err:
     g_free(s->vhost_vqs);
     s->vhost_vqs = NULL;