virtio ring packed supports resize.
Only after the new vring is successfully allocated based on the new num,
we will release the old vring. In any case, an error is returned,
indicating that the vring still points to the old vring. In the case of
an error, we will re-initialize the state of the vring to ensure that
the vring can be used.
Signed-off-by: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx>
---
drivers/virtio/virtio_ring.c | 28 ++++++++++++++++++++++++++++
1 file changed, 28 insertions(+)
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 73abc9e472ce..fb0abf9a2f57 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -1968,6 +1968,34 @@ static struct virtqueue *vring_create_virtqueue_packed(
return NULL;
}
+static int virtqueue_resize_packed(struct virtqueue *_vq, u32 num)
+{
+ struct vring_virtqueue *vq = to_vvq(_vq);
+ struct virtio_device *vdev = _vq->vdev;
+ struct vring_packed vring;
+ int err;
+
+ err = vring_alloc_queue_packed(&vring, vdev, num);
+ if (err)
+ goto err_queue;
+
+ err = vring_alloc_state_extra_packed(num, &vring);
+ if (err)
+ goto err_state_extra;
+
+ __vring_free(&vq->vq);
+
+ vring_virtqueue_attach_packed(vq, &vring);
+ vring_virtqueue_init_packed(vq, vdev);
+ return 0;
+
+err_state_extra:
+ vring_free_vring_packed(&vring, vdev);
+err_queue:
+ vring_virtqueue_init_packed(vq, vdev);
+ return -ENOMEM;
+}
+
/*
* Generic functions and exported symbols.
--
2.31.0
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