[dpdk-dev] [PATCH v4 10/44] net/virtio: force IOVA as VA mode for Virtio-user

[Maxime Coquelin <maxime.coquelin@redhat.com>]

At least Vhost-user backend of Virtio-user PMD requires
IOVA as VA mode. Until now, it was implemented as a hack
by forcing to use mbuf's buf_addr field instead of buf_iova.

This patch removes all this logic and just fails probing
if IOVA as VA mode is not selected. It simplifies the
code overall, and removes some bus-specific logic from
generic virtio_ethdev.c.

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: Chenbo Xia <chenbo.xia@intel.com>
---
 drivers/net/virtio/virtio_ethdev.c           | 15 ---------
 drivers/net/virtio/virtio_rxtx.c             | 34 ++++++++------------
 drivers/net/virtio/virtio_rxtx_packed.h      |  2 +-
 drivers/net/virtio/virtio_rxtx_packed_avx.h  |  8 ++---
 drivers/net/virtio/virtio_rxtx_packed_neon.h |  8 ++---
 drivers/net/virtio/virtio_rxtx_simple.h      |  3 +-
 drivers/net/virtio/virtio_user_ethdev.c      |  1 +
 drivers/net/virtio/virtqueue.h               | 25 +-------------
 8 files changed, 26 insertions(+), 70 deletions(-)

diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index 52eb878c42..fb789460e8 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -576,21 +576,6 @@ virtio_init_queue(struct rte_eth_dev *dev, uint16_t vtpci_queue_idx)
 		hw->cvq = cvq;
 	}
 
-	/* For virtio_user case (that is when hw->virtio_user_dev is not NULL),
-	 * we use virtual address. And we need properly set _offset_, please see
-	 * VIRTIO_MBUF_DATA_DMA_ADDR in virtqueue.h for more information.
-	 */
-	if (hw->bus_type == VIRTIO_BUS_PCI_LEGACY || hw->bus_type == VIRTIO_BUS_PCI_MODERN) {
-		vq->offset = offsetof(struct rte_mbuf, buf_iova);
-	} else if (hw->bus_type == VIRTIO_BUS_USER) {
-		vq->vq_ring_mem = (uintptr_t)mz->addr;
-		vq->offset = offsetof(struct rte_mbuf, buf_addr);
-		if (queue_type == VTNET_TQ)
-			txvq->virtio_net_hdr_mem = (uintptr_t)hdr_mz->addr;
-		else if (queue_type == VTNET_CQ)
-			cvq->virtio_net_hdr_mem = (uintptr_t)hdr_mz->addr;
-	}
-
 	if (queue_type == VTNET_TQ) {
 		struct virtio_tx_region *txr;
 		unsigned int i;
diff --git a/drivers/net/virtio/virtio_rxtx.c b/drivers/net/virtio/virtio_rxtx.c
index 622d4bf201..6875c8fbee 100644
--- a/drivers/net/virtio/virtio_rxtx.c
+++ b/drivers/net/virtio/virtio_rxtx.c
@@ -271,13 +271,10 @@ virtqueue_enqueue_refill_inorder(struct virtqueue *vq,
 		dxp->cookie = (void *)cookies[i];
 		dxp->ndescs = 1;
 
-		start_dp[idx].addr =
-				VIRTIO_MBUF_ADDR(cookies[i], vq) +
-				RTE_PKTMBUF_HEADROOM - hw->vtnet_hdr_size;
-		start_dp[idx].len =
-				cookies[i]->buf_len -
-				RTE_PKTMBUF_HEADROOM +
-				hw->vtnet_hdr_size;
+		start_dp[idx].addr = cookies[i]->buf_iova +
+			RTE_PKTMBUF_HEADROOM - hw->vtnet_hdr_size;
+		start_dp[idx].len = cookies[i]->buf_len -
+			RTE_PKTMBUF_HEADROOM + hw->vtnet_hdr_size;
 		start_dp[idx].flags =  VRING_DESC_F_WRITE;
 
 		vq_update_avail_ring(vq, idx);
@@ -313,12 +310,10 @@ virtqueue_enqueue_recv_refill(struct virtqueue *vq, struct rte_mbuf **cookie,
 		dxp->cookie = (void *)cookie[i];
 		dxp->ndescs = 1;
 
-		start_dp[idx].addr =
-			VIRTIO_MBUF_ADDR(cookie[i], vq) +
+		start_dp[idx].addr = cookie[i]->buf_iova +
 			RTE_PKTMBUF_HEADROOM - hw->vtnet_hdr_size;
-		start_dp[idx].len =
-			cookie[i]->buf_len - RTE_PKTMBUF_HEADROOM +
-			hw->vtnet_hdr_size;
+		start_dp[idx].len = cookie[i]->buf_len -
+			RTE_PKTMBUF_HEADROOM + hw->vtnet_hdr_size;
 		start_dp[idx].flags = VRING_DESC_F_WRITE;
 		vq->vq_desc_head_idx = start_dp[idx].next;
 		vq_update_avail_ring(vq, idx);
@@ -355,10 +350,10 @@ virtqueue_enqueue_recv_refill_packed(struct virtqueue *vq,
 		dxp->cookie = (void *)cookie[i];
 		dxp->ndescs = 1;
 
-		start_dp[idx].addr = VIRTIO_MBUF_ADDR(cookie[i], vq) +
-				RTE_PKTMBUF_HEADROOM - hw->vtnet_hdr_size;
-		start_dp[idx].len = cookie[i]->buf_len - RTE_PKTMBUF_HEADROOM
-					+ hw->vtnet_hdr_size;
+		start_dp[idx].addr = cookie[i]->buf_iova +
+			RTE_PKTMBUF_HEADROOM - hw->vtnet_hdr_size;
+		start_dp[idx].len = cookie[i]->buf_len -
+			RTE_PKTMBUF_HEADROOM + hw->vtnet_hdr_size;
 
 		vq->vq_desc_head_idx = dxp->next;
 		if (vq->vq_desc_head_idx == VQ_RING_DESC_CHAIN_END)
@@ -455,8 +450,7 @@ virtqueue_enqueue_xmit_inorder(struct virtnet_tx *txvq,
 		else
 			virtqueue_xmit_offload(hdr, cookies[i], true);
 
-		start_dp[idx].addr  =
-			VIRTIO_MBUF_DATA_DMA_ADDR(cookies[i], vq) - head_size;
+		start_dp[idx].addr  = rte_mbuf_data_iova(cookies[i]) - head_size;
 		start_dp[idx].len   = cookies[i]->data_len + head_size;
 		start_dp[idx].flags = 0;
 
@@ -503,7 +497,7 @@ virtqueue_enqueue_xmit_packed_fast(struct virtnet_tx *txvq,
 	else
 		virtqueue_xmit_offload(hdr, cookie, true);
 
-	dp->addr = VIRTIO_MBUF_DATA_DMA_ADDR(cookie, vq) - head_size;
+	dp->addr = rte_mbuf_data_iova(cookie) - head_size;
 	dp->len  = cookie->data_len + head_size;
 	dp->id   = id;
 
@@ -590,7 +584,7 @@ virtqueue_enqueue_xmit(struct virtnet_tx *txvq, struct rte_mbuf *cookie,
 	virtqueue_xmit_offload(hdr, cookie, vq->hw->has_tx_offload);
 
 	do {
-		start_dp[idx].addr  = VIRTIO_MBUF_DATA_DMA_ADDR(cookie, vq);
+		start_dp[idx].addr  = rte_mbuf_data_iova(cookie);
 		start_dp[idx].len   = cookie->data_len;
 		if (prepend_header) {
 			start_dp[idx].addr -= head_size;
diff --git a/drivers/net/virtio/virtio_rxtx_packed.h b/drivers/net/virtio/virtio_rxtx_packed.h
index 016b6fb247..c0fad41c3d 100644
--- a/drivers/net/virtio/virtio_rxtx_packed.h
+++ b/drivers/net/virtio/virtio_rxtx_packed.h
@@ -288,7 +288,7 @@ virtio_recv_refill_packed_vec(struct virtnet_rx *rxvq,
 			dxp = &vq->vq_descx[idx + i];
 			dxp->cookie = (void *)cookie[total_num + i];
 
-			addr = VIRTIO_MBUF_ADDR(cookie[total_num + i], vq) +
+			addr = cookie[total_num + i]->buf_iova +
 				RTE_PKTMBUF_HEADROOM - hw->vtnet_hdr_size;
 			start_dp[idx + i].addr = addr;
 			start_dp[idx + i].len = cookie[total_num + i]->buf_len
diff --git a/drivers/net/virtio/virtio_rxtx_packed_avx.h b/drivers/net/virtio/virtio_rxtx_packed_avx.h
index f831828845..2c610d57de 100644
--- a/drivers/net/virtio/virtio_rxtx_packed_avx.h
+++ b/drivers/net/virtio/virtio_rxtx_packed_avx.h
@@ -71,13 +71,13 @@ virtqueue_enqueue_batch_packed_vec(struct virtnet_tx *txvq,
 	}
 
 	__m512i descs_base = _mm512_set_epi64(tx_pkts[3]->data_len,
-			VIRTIO_MBUF_ADDR(tx_pkts[3], vq),
+			tx_pkts[3]->buf_iova,
 			tx_pkts[2]->data_len,
-			VIRTIO_MBUF_ADDR(tx_pkts[2], vq),
+			tx_pkts[2]->buf_iova,
 			tx_pkts[1]->data_len,
-			VIRTIO_MBUF_ADDR(tx_pkts[1], vq),
+			tx_pkts[1]->buf_iova,
 			tx_pkts[0]->data_len,
-			VIRTIO_MBUF_ADDR(tx_pkts[0], vq));
+			tx_pkts[0]->buf_iova);
 
 	/* id offset and data offset */
 	__m512i data_offsets = _mm512_set_epi64((uint64_t)3 << ID_BITS_OFFSET,
diff --git a/drivers/net/virtio/virtio_rxtx_packed_neon.h b/drivers/net/virtio/virtio_rxtx_packed_neon.h
index 01c77b712d..ae2d099c0b 100644
--- a/drivers/net/virtio/virtio_rxtx_packed_neon.h
+++ b/drivers/net/virtio/virtio_rxtx_packed_neon.h
@@ -97,12 +97,12 @@ virtqueue_enqueue_batch_packed_vec(struct virtnet_tx *txvq,
 
 	uint64x2x2_t desc[PACKED_BATCH_SIZE / 2];
 	uint64x2_t base_addr0 = {
-		VIRTIO_MBUF_ADDR(tx_pkts[0], vq) + tx_pkts[0]->data_off,
-		VIRTIO_MBUF_ADDR(tx_pkts[1], vq) + tx_pkts[1]->data_off
+		tx_pkts[0]->buf_iova + tx_pkts[0]->data_off,
+		tx_pkts[1]->buf_iova + tx_pkts[1]->data_off
 	};
 	uint64x2_t base_addr1 = {
-		VIRTIO_MBUF_ADDR(tx_pkts[2], vq) + tx_pkts[2]->data_off,
-		VIRTIO_MBUF_ADDR(tx_pkts[3], vq) + tx_pkts[3]->data_off
+		tx_pkts[2]->buf_iova + tx_pkts[2]->data_off,
+		tx_pkts[3]->buf_iova + tx_pkts[3]->data_off
 	};
 
 	desc[0].val[0] = base_addr0;
diff --git a/drivers/net/virtio/virtio_rxtx_simple.h b/drivers/net/virtio/virtio_rxtx_simple.h
index 3d1296a23c..f2a5aedf97 100644
--- a/drivers/net/virtio/virtio_rxtx_simple.h
+++ b/drivers/net/virtio/virtio_rxtx_simple.h
@@ -43,8 +43,7 @@ virtio_rxq_rearm_vec(struct virtnet_rx *rxvq)
 		p = (uintptr_t)&sw_ring[i]->rearm_data;
 		*(uint64_t *)p = rxvq->mbuf_initializer;
 
-		start_dp[i].addr =
-			VIRTIO_MBUF_ADDR(sw_ring[i], vq) +
+		start_dp[i].addr = sw_ring[i]->buf_iova +
 			RTE_PKTMBUF_HEADROOM - vq->hw->vtnet_hdr_size;
 		start_dp[i].len = sw_ring[i]->buf_len -
 			RTE_PKTMBUF_HEADROOM + vq->hw->vtnet_hdr_size;
diff --git a/drivers/net/virtio/virtio_user_ethdev.c b/drivers/net/virtio/virtio_user_ethdev.c
index 620ecb126c..241fe373b9 100644
--- a/drivers/net/virtio/virtio_user_ethdev.c
+++ b/drivers/net/virtio/virtio_user_ethdev.c
@@ -953,6 +953,7 @@ static struct rte_vdev_driver virtio_user_driver = {
 	.remove = virtio_user_pmd_remove,
 	.dma_map = virtio_user_pmd_dma_map,
 	.dma_unmap = virtio_user_pmd_dma_unmap,
+	.drv_flags = RTE_VDEV_DRV_NEED_IOVA_AS_VA,
 };
 
 RTE_PMD_REGISTER_VDEV(net_virtio_user, virtio_user_driver);
diff --git a/drivers/net/virtio/virtqueue.h b/drivers/net/virtio/virtqueue.h
index d78b943443..7611317581 100644
--- a/drivers/net/virtio/virtqueue.h
+++ b/drivers/net/virtio/virtqueue.h
@@ -113,29 +113,6 @@ virtqueue_store_flags_packed(struct vring_packed_desc *dp,
 
 #define VIRTQUEUE_MAX_NAME_SZ 32
 
-#ifdef RTE_VIRTIO_USER
-/**
- * Return the physical address (or virtual address in case of
- * virtio-user) of mbuf data buffer.
- *
- * The address is firstly casted to the word size (sizeof(uintptr_t))
- * before casting it to uint64_t. This is to make it work with different
- * combination of word size (64 bit and 32 bit) and virtio device
- * (virtio-pci and virtio-user).
- */
-#define VIRTIO_MBUF_ADDR(mb, vq) \
-	((uint64_t)(*(uintptr_t *)((uintptr_t)(mb) + (vq)->offset)))
-#else
-#define VIRTIO_MBUF_ADDR(mb, vq) ((mb)->buf_iova)
-#endif
-
-/**
- * Return the physical address (or virtual address in case of
- * virtio-user) of mbuf data buffer, taking care of mbuf data offset
- */
-#define VIRTIO_MBUF_DATA_DMA_ADDR(mb, vq) \
-	(VIRTIO_MBUF_ADDR(mb, vq) + (mb)->data_off)
-
 #define VTNET_SQ_RQ_QUEUE_IDX 0
 #define VTNET_SQ_TQ_QUEUE_IDX 1
 #define VTNET_SQ_CQ_QUEUE_IDX 2
@@ -763,7 +740,7 @@ virtqueue_enqueue_xmit_packed(struct virtnet_tx *txvq, struct rte_mbuf *cookie,
 	do {
 		uint16_t flags;
 
-		start_dp[idx].addr = VIRTIO_MBUF_DATA_DMA_ADDR(cookie, vq);
+		start_dp[idx].addr = rte_mbuf_data_iova(cookie);
 		start_dp[idx].len  = cookie->data_len;
 		if (prepend_header) {
 			start_dp[idx].addr -= head_size;
-- 
2.29.2