Performing reset on a queue is divided into four steps:

 1. transport: notify the device to reset the queue
 2. vring:     recycle the buffer submitted
 3. vring:     reset/resize the vring (may re-alloc)
 4. transport: mmap vring to device, and enable the queue

In order to support queue reset, add two callbacks(reset_vq,
enable_reset_vq) in struct virtio_config_ops to implement steps 1 and 4.

Signed-off-by: Xuan Zhuo <xuanz...@linux.alibaba.com>
---
 include/linux/virtio_config.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
index 4d107ad31149..d4adcd0e1c57 100644
--- a/include/linux/virtio_config.h
+++ b/include/linux/virtio_config.h
@@ -74,6 +74,16 @@ struct virtio_shm_region {
  * @set_vq_affinity: set the affinity for a virtqueue (optional).
  * @get_vq_affinity: get the affinity for a virtqueue (optional).
  * @get_shm_region: get a shared memory region based on the index.
+ * @reset_vq: reset a queue individually (optional).
+ *     vq: the virtqueue
+ *     Returns 0 on success or error status
+ *     reset_vq will guarantee that the callbacks are disabled and 
synchronized.
+ *     Except for the callback, the caller should guarantee that the vring is
+ *     not accessed by any functions of virtqueue.
+ * @enable_reset_vq: enable a reset queue
+ *     vq: the virtqueue
+ *     Returns 0 on success or error status
+ *     If reset_vq is set, then enable_reset_vq must also be set.
  */
 typedef void vq_callback_t(struct virtqueue *);
 struct virtio_config_ops {
@@ -100,6 +110,8 @@ struct virtio_config_ops {
                        int index);
        bool (*get_shm_region)(struct virtio_device *vdev,
                               struct virtio_shm_region *region, u8 id);
+       int (*reset_vq)(struct virtqueue *vq);
+       int (*enable_reset_vq)(struct virtqueue *vq);
 };
 
 /* If driver didn't advertise the feature, it will never appear. */
-- 
2.31.0

_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization

Reply via email to