[PATCH v12 20/40] virtio_ring: packed: introduce virtqueue_reinit_packed()

Xuan Zhuo
2022-07-20T03:07:48Z

Introduce a function to initialize vq without allocating new ring,
desc_state, desc_extra.

Subsequent patches will call this function after reset vq to
reinitialize vq.

Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
---
drivers/virtio/virtio_ring.c | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)

diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 3bbeb385fb8c..5802cd373fd1 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -1963,6 +1963,27 @@ static void virtqueue_vring_init_packed(struct vring_virtqueue *vq)
}
}

+static void virtqueue_reinit_packed(struct vring_virtqueue *vq)
+{
+ int size, i;
+
+ memset(vq->packed.vring.device, 0, vq->packed.event_size_in_bytes);
+ memset(vq->packed.vring.driver, 0, vq->packed.event_size_in_bytes);
+ memset(vq->packed.vring.desc, 0, vq->packed.ring_size_in_bytes);
+
+ size = sizeof(struct vring_desc_state_packed) * vq->packed.vring.num;
+ memset(vq->packed.desc_state, 0, size);
+
+ size = sizeof(struct vring_desc_extra) * vq->packed.vring.num;
+ memset(vq->packed.desc_extra, 0, size);
+
+ for (i = 0; i < vq->packed.vring.num - 1; i++)
+ vq->packed.desc_extra[i].next = i + 1;
+
+ virtqueue_init(vq, vq->packed.vring.num);
+ virtqueue_vring_init_packed(vq);
+}
+
static struct virtqueue *vring_create_virtqueue_packed(
unsigned int index,
unsigned int num,
--
2.31.0