[PATCH v5 15/22] virtio: queue_reset: add helper

Xuan Zhuo
2022-02-14T08:14:09Z

Add helper for virtio queue reset.

* virtio_reset_vq: reset a queue individually
* virtio_enable_resetq: enable a reset queue

Signed-off-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com>
---
 include/linux/virtio_config.h | 38 +++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
index 8cde339d40b4..cd7f7f44ce38 100644
--- a/include/linux/virtio_config.h
+++ b/include/linux/virtio_config.h
@@ -233,6 +233,44 @@ int virtio_find_vqs_ctx(struct virtio_device *vdev,
unsigned nvqs,
 				      desc);
 }

+/**
+ * virtio_reset_vq - reset a queue individually
+ * @vq: the virtqueue
+ *
+ * returns 0 on success or error status
+ *
+ * After successfully calling this, be sure to call
+ * virtqueue_detach_unused_buf() to recycle the buffer in the ring, and
+ * then call vring_release_virtqueue() to release the vq ring.
+ *
+ * Caller should guarantee that the vring is not accessed by any functions
+ * of virtqueue.
+ */
+static inline
+int virtio_reset_vq(struct virtqueue *vq)
+{
+	if (!vq->vdev->config->reset_vq)
+		return -ENOENT;
+
+	return vq->vdev->config->reset_vq(vq);
+}
+
+/**
+ * virtio_enable_resetq - enable a reset queue
+ * @vq: the virtqueue
+ *
+ * returns 0 on success or error status
+ *
+ */
+static inline
+int virtio_enable_resetq(struct virtqueue *vq)
+{
+	if (!vq->vdev->config->enable_reset_vq)
+		return -ENOENT;
+
+	return vq->vdev->config->enable_reset_vq(vq);
+}
+
 /**
  * virtio_device_ready - enable vq use in probe function
  * @vdev: the device
--
2.31.0