[PATCH v3 1/3] net/virtio_user: convert cq descriptor IOVA address to Virtual address

[Srujana Challa]

This patch modifies the code to convert descriptor buffer IOVA
addresses to virtual addresses during the processing of shadow
control queue when IOVA mode is PA. This change enables Virtio-user
to operate with IOVA as the descriptor buffer address.

Signed-off-by: Srujana Challa <schalla at marvell.com>
---
 .../net/virtio/virtio_user/virtio_user_dev.c  | 33 ++++++++++++-------
 1 file changed, 21 insertions(+), 12 deletions(-)

diff --git a/drivers/net/virtio/virtio_user/virtio_user_dev.c b/drivers/net/virtio/virtio_user/virtio_user_dev.c
index 1365c8a5c8..7f35f4b06b 100644
--- a/drivers/net/virtio/virtio_user/virtio_user_dev.c
+++ b/drivers/net/virtio/virtio_user/virtio_user_dev.c
@@ -896,6 +896,15 @@ virtio_user_handle_mq(struct virtio_user_dev *dev, uint16_t q_pairs)
 
 #define CVQ_MAX_DATA_DESCS 32
 
+static inline void *
+virtio_user_iova2virt(rte_iova_t iova)
+{
+	if (rte_eal_iova_mode() == RTE_IOVA_PA)
+		return rte_mem_iova2virt(iova);
+	else
+		return (void *)(uintptr_t)iova;
+}
+
 static uint32_t
 virtio_user_handle_ctrl_msg_split(struct virtio_user_dev *dev, struct vring *vring,
 			    uint16_t idx_hdr)
@@ -921,17 +930,18 @@ virtio_user_handle_ctrl_msg_split(struct virtio_user_dev *dev, struct vring *vri
 	idx_status = i;
 	n_descs++;
 
-	hdr = (void *)(uintptr_t)vring->desc[idx_hdr].addr;
+	hdr = virtio_user_iova2virt(vring->desc[idx_hdr].addr);
 	if (hdr->class == VIRTIO_NET_CTRL_MQ &&
 	    hdr->cmd == VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET) {
-		uint16_t queues;
+		uint16_t queues, *addr;
 
-		queues = *(uint16_t *)(uintptr_t)vring->desc[idx_data].addr;
+		addr = virtio_user_iova2virt(vring->desc[idx_data].addr);
+		queues = *addr;
 		status = virtio_user_handle_mq(dev, queues);
 	} else if (hdr->class == VIRTIO_NET_CTRL_MQ && hdr->cmd == VIRTIO_NET_CTRL_MQ_RSS_CONFIG) {
 		struct virtio_net_ctrl_rss *rss;
 
-		rss = (struct virtio_net_ctrl_rss *)(uintptr_t)vring->desc[idx_data].addr;
+		rss = virtio_user_iova2virt(vring->desc[idx_data].addr);
 		status = virtio_user_handle_mq(dev, rss->max_tx_vq);
 	} else if (hdr->class == VIRTIO_NET_CTRL_RX  ||
 		   hdr->class == VIRTIO_NET_CTRL_MAC ||
@@ -944,7 +954,7 @@ virtio_user_handle_ctrl_msg_split(struct virtio_user_dev *dev, struct vring *vri
 				(struct virtio_pmd_ctrl *)hdr, dlen, nb_dlen);
 
 	/* Update status */
-	*(virtio_net_ctrl_ack *)(uintptr_t)vring->desc[idx_status].addr = status;
+	*(virtio_net_ctrl_ack *)virtio_user_iova2virt(vring->desc[idx_status].addr) = status;
 
 	return n_descs;
 }
@@ -986,18 +996,18 @@ virtio_user_handle_ctrl_msg_packed(struct virtio_user_dev *dev,
 		n_descs++;
 	}
 
-	hdr = (void *)(uintptr_t)vring->desc[idx_hdr].addr;
+	hdr = virtio_user_iova2virt(vring->desc[idx_hdr].addr);
 	if (hdr->class == VIRTIO_NET_CTRL_MQ &&
 	    hdr->cmd == VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET) {
-		uint16_t queues;
+		uint16_t queues, *addr;
 
-		queues = *(uint16_t *)(uintptr_t)
-				vring->desc[idx_data].addr;
+		addr = virtio_user_iova2virt(vring->desc[idx_data].addr);
+		queues = *addr;
 		status = virtio_user_handle_mq(dev, queues);
 	} else if (hdr->class == VIRTIO_NET_CTRL_MQ && hdr->cmd == VIRTIO_NET_CTRL_MQ_RSS_CONFIG) {
 		struct virtio_net_ctrl_rss *rss;
 
-		rss = (struct virtio_net_ctrl_rss *)(uintptr_t)vring->desc[idx_data].addr;
+		rss = virtio_user_iova2virt(vring->desc[idx_data].addr);
 		status = virtio_user_handle_mq(dev, rss->max_tx_vq);
 	} else if (hdr->class == VIRTIO_NET_CTRL_RX  ||
 		   hdr->class == VIRTIO_NET_CTRL_MAC ||
@@ -1010,8 +1020,7 @@ virtio_user_handle_ctrl_msg_packed(struct virtio_user_dev *dev,
 				(struct virtio_pmd_ctrl *)hdr, dlen, nb_dlen);
 
 	/* Update status */
-	*(virtio_net_ctrl_ack *)(uintptr_t)
-		vring->desc[idx_status].addr = status;
+	*(virtio_net_ctrl_ack *)virtio_user_iova2virt(vring->desc[idx_status].addr) = status;
 
 	/* Update used descriptor */
 	vring->desc[idx_hdr].id = vring->desc[idx_status].id;
-- 
2.25.1