在 2022/3/8 下午8:35, Xuan Zhuo 写道:
Performing reset on a queue is divided into four steps:
1. reset_vq() - notify the device to reset the queue
2. virtqueue_detach_unused_buf() - recycle the buffer submitted
3. virtqueue_reset_vring() - reset the vring (may re-alloc)
4. enable_reset_vq() - mmap vring to device, and enable the queue
So add two callbacks reset_vq, enable_reset_vq to struct
virtio_config_ops.
Signed-off-by: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx>
---
include/linux/virtio_config.h | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
index 4d107ad31149..d51906b1389f 100644
--- a/include/linux/virtio_config.h
+++ b/include/linux/virtio_config.h
@@ -74,6 +74,15 @@ 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
+ * Caller should guarantee that the vring is not accessed by any functions
+ * of virtqueue.
We probably need to be more accurate here:
1) reset_vq will guarantee that the callbacks are disabled or synchronized
2) except for the callback, the caller should guarantee ...
Thanks
+ * @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 +109,8 @@ 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. */
