[PATCH 19.11] net/virtio: fix indirect descriptor reconnection

[xuan.ding@intel.com]

From: Xuan Ding <xuan.ding@intel.com>

[ upstream commit 04bcc80204db16ca77d1dd11a6ea1773214cc755 ]

Add initialization for packed ring indirect descriptors
in reconnection path.

Fixes: 8c1df8846b15 ("net/virtio: fix packed ring indirect descricptors setup")

Signed-off-by: Xuan Ding <xuan.ding@intel.com>
Tested-by: Yinan Wang <yinan.wang@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
---
 drivers/net/virtio/virtqueue.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/drivers/net/virtio/virtqueue.c b/drivers/net/virtio/virtqueue.c
index 02c8b9fc5..8195aaa8c 100644
--- a/drivers/net/virtio/virtqueue.c
+++ b/drivers/net/virtio/virtqueue.c
@@ -185,6 +185,8 @@ virtqueue_txvq_reset_packed(struct virtqueue *vq)
 	struct vq_desc_extra *dxp;
 	struct virtnet_tx *txvq;
 	uint16_t desc_idx;
+	struct virtio_tx_region *txr;
+	struct vring_packed_desc *start_dp;
 
 	vq->vq_used_cons_idx = 0;
 	vq->vq_desc_head_idx = 0;
@@ -197,6 +199,7 @@ virtqueue_txvq_reset_packed(struct virtqueue *vq)
 	vq->vq_packed.event_flags_shadow = 0;
 
 	txvq = &vq->txq;
+	txr = txvq->virtio_net_hdr_mz->addr;
 	memset(txvq->mz->addr, 0, txvq->mz->len);
 	memset(txvq->virtio_net_hdr_mz->addr, 0,
 		txvq->virtio_net_hdr_mz->len);
@@ -207,6 +210,17 @@ virtqueue_txvq_reset_packed(struct virtqueue *vq)
 			rte_pktmbuf_free(dxp->cookie);
 			dxp->cookie = NULL;
 		}
+
+		if (vtpci_with_feature(vq->hw, VIRTIO_RING_F_INDIRECT_DESC)) {
+			/* first indirect descriptor is always the tx header */
+			start_dp = txr[desc_idx].tx_packed_indir;
+			vring_desc_init_indirect_packed(start_dp,
+				RTE_DIM(txr[desc_idx].tx_packed_indir));
+			start_dp->addr = txvq->virtio_net_hdr_mem
+				+ desc_idx * sizeof(*txr)
+				+ offsetof(struct virtio_tx_region, tx_hdr);
+			start_dp->len = vq->hw->vtnet_hdr_size;
+		}
 	}
 
 	vring_desc_init_packed(vq, size);
-- 
2.17.1