+/*
+ * Returns 1 if queue is full and sender should wait a bit before sending
+ * next request, 0 otherwise.
+ */
+static int send_forget_request(struct virtio_fs_vq *fsvq,
+ struct virtio_fs_forget *forget,
+ bool in_flight)
+{
+ struct scatterlist sg;
+ struct virtqueue *vq;
+ int ret = 0;
+ bool notify;
+
+ spin_lock(&fsvq->lock);
+ if (!fsvq->connected) {
+ if (in_flight)
+ dec_in_flight_req(fsvq);
+ kfree(forget);
+ goto out;
+ }
+
+ sg_init_one(&sg, forget, sizeof(*forget));
+ vq = fsvq->vq;
+ dev_dbg(&vq->vdev->dev, "%s\n", __func__);
+
+ ret = virtqueue_add_outbuf(vq, &sg, 1, forget, GFP_ATOMIC);
+ if (ret < 0) {
+ if (ret == -ENOMEM || ret == -ENOSPC) {
+ pr_debug("virtio-fs: Could not queue FORGET: err=%d. Will try later\n",
+ ret);
+ list_add_tail(&forget->list, &fsvq->queued_reqs);
+ schedule_delayed_work(&fsvq->dispatch_work,
+ msecs_to_jiffies(1));
+ if (!in_flight)
+ inc_in_flight_req(fsvq);
+ /* Queue is full */
+ ret = 1;
+ } else {
+ pr_debug("virtio-fs: Could not queue FORGET: err=%d. Dropping it.\n",
+ ret);
+ kfree(forget);
+ if (in_flight)
+ dec_in_flight_req(fsvq);
+ }
+ goto out;
+ }
+
+ if (!in_flight)
+ inc_in_flight_req(fsvq);
+ notify = virtqueue_kick_prepare(vq);
+ spin_unlock(&fsvq->lock);
+
+ if (notify)
+ virtqueue_notify(vq);
+ return ret;
+out:
+ spin_unlock(&fsvq->lock);
+ return ret;
+}
+