net/virtio: revert forcing IOVA as VA mode for virtio-user

This patch removes the simplification in Virtio descriptors
handling, where their buffer addresses are IOVAs for Virtio
PCI devices, and VA-only for Virtio-user devices, which
added a requirement on Virtio-user that it only supported
IOVA as VA.

This change introduced a regression for applications using
Virtio-user and other physical PMDs that require IOVA as PA
because they don't use an IOMMU.

This patch reverts to the old behaviour, but needed to be
reworked because of the refactoring that happened in v21.02.

Fixes: 17043a2909bb ("net/virtio: force IOVA as VA mode for virtio-user")
Cc: stable@dpdk.org
Reported-by: Olivier Matz <olivier.matz@6wind.com>
Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Tested-by: Olivier Matz <olivier.matz@6wind.com>
Reviewed-by: David Marchand <david.marchand@redhat.com>

diff --git a/drivers/net/virtio/virtio.h b/drivers/net/virtio/virtio.h
index 525e2da..e78b2e4 100644 (file)
--- a/drivers/net/virtio/virtio.h
+++ b/drivers/net/virtio/virtio.h
@@ -192,6 +192,7 @@ struct virtio_hw {
        uint16_t max_queue_pairs;
        uint64_t req_guest_features;
        struct virtnet_ctl *cvq;
+       bool use_va;
 };
 
 struct virtio_ops {

diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index b08109c..b60eeb2 100644 (file)
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -515,12 +515,14 @@ virtio_init_queue(struct rte_eth_dev *dev, uint16_t queue_idx)
 
        memset(mz->addr, 0, mz->len);
 
-       vq->vq_ring_mem = mz->iova;
+       if (hw->use_va)
+               vq->vq_ring_mem = (uintptr_t)mz->addr;
+       else
+               vq->vq_ring_mem = mz->iova;
+
        vq->vq_ring_virt_mem = mz->addr;
-       PMD_INIT_LOG(DEBUG, "vq->vq_ring_mem:      0x%" PRIx64,
-                    (uint64_t)mz->iova);
-       PMD_INIT_LOG(DEBUG, "vq->vq_ring_virt_mem: 0x%" PRIx64,
-                    (uint64_t)(uintptr_t)mz->addr);
+       PMD_INIT_LOG(DEBUG, "vq->vq_ring_mem: 0x%" PRIx64, vq->vq_ring_mem);
+       PMD_INIT_LOG(DEBUG, "vq->vq_ring_virt_mem: %p", vq->vq_ring_virt_mem);
 
        virtio_init_vring(vq);
 
@@ -570,17 +572,28 @@ virtio_init_queue(struct rte_eth_dev *dev, uint16_t queue_idx)
                txvq->port_id = dev->data->port_id;
                txvq->mz = mz;
                txvq->virtio_net_hdr_mz = hdr_mz;
-               txvq->virtio_net_hdr_mem = hdr_mz->iova;
+               if (hw->use_va)
+                       txvq->virtio_net_hdr_mem = (uintptr_t)hdr_mz->addr;
+               else
+                       txvq->virtio_net_hdr_mem = hdr_mz->iova;
        } else if (queue_type == VTNET_CQ) {
                cvq = &vq->cq;
                cvq->mz = mz;
                cvq->virtio_net_hdr_mz = hdr_mz;
-               cvq->virtio_net_hdr_mem = hdr_mz->iova;
+               if (hw->use_va)
+                       cvq->virtio_net_hdr_mem = (uintptr_t)hdr_mz->addr;
+               else
+                       cvq->virtio_net_hdr_mem = hdr_mz->iova;
                memset(cvq->virtio_net_hdr_mz->addr, 0, rte_mem_page_size());
 
                hw->cvq = cvq;
        }
 
+       if (hw->use_va)
+               vq->mbuf_addr_offset = offsetof(struct rte_mbuf, buf_addr);
+       else
+               vq->mbuf_addr_offset = offsetof(struct rte_mbuf, buf_iova);
+
        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 b9d7c8d..e8e6ed2 100644 (file)
--- a/drivers/net/virtio/virtio_rxtx.c
+++ b/drivers/net/virtio/virtio_rxtx.c
@@ -271,7 +271,7 @@ virtqueue_enqueue_refill_inorder(struct virtqueue *vq,
                dxp->cookie = (void *)cookies[i];
                dxp->ndescs = 1;
 
-               start_dp[idx].addr = cookies[i]->buf_iova +
+               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;
@@ -310,10 +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 = cookie[i]->buf_iova +
+               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].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);
@@ -336,13 +336,10 @@ virtqueue_refill_single_packed(struct virtqueue *vq,
        uint16_t flags = vq->vq_packed.cached_flags;
        struct virtio_hw *hw = vq->hw;
 
-       dp->addr = cookie->buf_iova +
-                       RTE_PKTMBUF_HEADROOM - hw->vtnet_hdr_size;
-       dp->len = cookie->buf_len -
-               RTE_PKTMBUF_HEADROOM + hw->vtnet_hdr_size;
+       dp->addr = VIRTIO_MBUF_ADDR(cookie, vq) + RTE_PKTMBUF_HEADROOM - hw->vtnet_hdr_size;
+       dp->len = cookie->buf_len - RTE_PKTMBUF_HEADROOM + hw->vtnet_hdr_size;
 
-       virtqueue_store_flags_packed(dp, flags,
-                                    hw->weak_barriers);
+       virtqueue_store_flags_packed(dp, flags, hw->weak_barriers);
 
        if (++vq->vq_avail_idx >= vq->vq_nentries) {
                vq->vq_avail_idx -= vq->vq_nentries;
@@ -482,8 +479,8 @@ virtqueue_enqueue_xmit_inorder(struct virtnet_tx *txvq,
                else
                        virtqueue_xmit_offload(hdr, cookies[i]);
 
-               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].addr = VIRTIO_MBUF_DATA_DMA_ADDR(cookies[i], vq) - head_size;
+               start_dp[idx].len = cookies[i]->data_len + head_size;
                start_dp[idx].flags = 0;
 
 
@@ -529,9 +526,9 @@ virtqueue_enqueue_xmit_packed_fast(struct virtnet_tx *txvq,
        else
                virtqueue_xmit_offload(hdr, cookie);
 
-       dp->addr = rte_mbuf_data_iova(cookie) - head_size;
-       dp->len  = cookie->data_len + head_size;
-       dp->id   = id;
+       dp->addr = VIRTIO_MBUF_DATA_DMA_ADDR(cookie, vq) - head_size;
+       dp->len = cookie->data_len + head_size;
+       dp->id = id;
 
        if (++vq->vq_avail_idx >= vq->vq_nentries) {
                vq->vq_avail_idx -= vq->vq_nentries;
@@ -617,8 +614,8 @@ virtqueue_enqueue_xmit(struct virtnet_tx *txvq, struct rte_mbuf *cookie,
                virtqueue_xmit_offload(hdr, cookie);
 
        do {
-               start_dp[idx].addr  = rte_mbuf_data_iova(cookie);
-               start_dp[idx].len   = cookie->data_len;
+               start_dp[idx].addr = VIRTIO_MBUF_DATA_DMA_ADDR(cookie, vq);
+               start_dp[idx].len = cookie->data_len;
                if (prepend_header) {
                        start_dp[idx].addr -= head_size;
                        start_dp[idx].len += head_size;

diff --git a/drivers/net/virtio/virtio_rxtx_packed.h b/drivers/net/virtio/virtio_rxtx_packed.h
index 1d1db60..77e5cb3 100644 (file)
--- 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 = cookie[total_num + i]->buf_iova +
+                       addr = VIRTIO_MBUF_ADDR(cookie[total_num + i], vq) +
                                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 c819d2e..8cb71f3 100644 (file)
--- 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,
-                       tx_pkts[3]->buf_iova,
+                       VIRTIO_MBUF_ADDR(tx_pkts[3], vq),
                        tx_pkts[2]->data_len,
-                       tx_pkts[2]->buf_iova,
+                       VIRTIO_MBUF_ADDR(tx_pkts[2], vq),
                        tx_pkts[1]->data_len,
-                       tx_pkts[1]->buf_iova,
+                       VIRTIO_MBUF_ADDR(tx_pkts[1], vq),
                        tx_pkts[0]->data_len,
-                       tx_pkts[0]->buf_iova);
+                       VIRTIO_MBUF_ADDR(tx_pkts[0], vq));
 
        /* 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 f19e618..c222ebf 100644 (file)
--- 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 = {
-               tx_pkts[0]->buf_iova + tx_pkts[0]->data_off,
-               tx_pkts[1]->buf_iova + tx_pkts[1]->data_off
+               VIRTIO_MBUF_ADDR(tx_pkts[0], vq) + tx_pkts[0]->data_off,
+               VIRTIO_MBUF_ADDR(tx_pkts[1], vq) + tx_pkts[1]->data_off
        };
        uint64x2_t base_addr1 = {
-               tx_pkts[2]->buf_iova + tx_pkts[2]->data_off,
-               tx_pkts[3]->buf_iova + tx_pkts[3]->data_off
+               VIRTIO_MBUF_ADDR(tx_pkts[2], vq) + tx_pkts[2]->data_off,
+               VIRTIO_MBUF_ADDR(tx_pkts[3], vq) + 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 f258771..d8f96e0 100644 (file)
--- a/drivers/net/virtio/virtio_rxtx_simple.h
+++ b/drivers/net/virtio/virtio_rxtx_simple.h
@@ -43,7 +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 = sw_ring[i]->buf_iova +
+               start_dp[i].addr = VIRTIO_MBUF_ADDR(sw_ring[i], vq) +
                        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 688c110..0271098 100644 (file)
--- a/drivers/net/virtio/virtio_user_ethdev.c
+++ b/drivers/net/virtio/virtio_user_ethdev.c
@@ -657,6 +657,12 @@ virtio_user_pmd_probe(struct rte_vdev_device *vdev)
                goto end;
        }
 
+       /*
+        * Virtio-user requires using virtual addresses for the descriptors
+        * buffers, whatever other devices require
+        */
+       hw->use_va = true;
+
        /* previously called by pci probing for physical dev */
        if (eth_virtio_dev_init(eth_dev) < 0) {
                PMD_INIT_LOG(ERR, "eth_virtio_dev_init fails");
@@ -769,7 +775,6 @@ 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 d0c48ca..5baac22 100644 (file)
--- a/drivers/net/virtio/virtqueue.h
+++ b/drivers/net/virtio/virtqueue.h
@@ -113,6 +113,25 @@ virtqueue_store_flags_packed(struct vring_packed_desc *dp,
 
 #define VIRTQUEUE_MAX_NAME_SZ 32
 
+/**
+ * Return the IOVA (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)->mbuf_addr_offset)))
+
+/**
+ * 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
@@ -255,6 +274,7 @@ struct virtqueue {
 
        void *vq_ring_virt_mem;  /**< linear address of vring*/
        unsigned int vq_ring_size;
+       uint16_t mbuf_addr_offset;
 
        union {
                struct virtnet_rx rxq;
@@ -739,7 +759,7 @@ virtqueue_enqueue_xmit_packed(struct virtnet_tx *txvq, struct rte_mbuf *cookie,
        do {
                uint16_t flags;
 
-               start_dp[idx].addr = rte_mbuf_data_iova(cookie);
+               start_dp[idx].addr = VIRTIO_MBUF_DATA_DMA_ADDR(cookie, vq);
                start_dp[idx].len  = cookie->data_len;
                if (prepend_header) {
                        start_dp[idx].addr -= head_size;