net/virtio: fix Rx scatter offload

Report Rx scatter offload capability depending on VIRTIO_NET_F_MRG_RXBUF.

If Rx scatter is not requested, ensure that provided Rx buffers on
each Rx queue are big enough to fit Rx packets up to configured MTU.

Fixes: ce17eddefc20 ("ethdev: introduce Rx queue offloads API")
Cc: stable@dpdk.org
Signed-off-by: Ivan Ilchenko <ivan.ilchenko@oktetlabs.ru>
Signed-off-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>

diff --git a/drivers/net/virtio/virtio.h b/drivers/net/virtio/virtio.h
index 2c987d1..525e2da 100644 (file)
--- a/drivers/net/virtio/virtio.h
+++ b/drivers/net/virtio/virtio.h
@@ -167,6 +167,7 @@ struct virtio_hw {
        uint8_t started;
        uint8_t weak_barriers;
        uint8_t vlan_strip;
+       bool rx_ol_scatter;
        uint8_t has_tx_offload;
        uint8_t has_rx_offload;
        uint8_t use_vec_rx;
@@ -180,6 +181,7 @@ struct virtio_hw {
        uint8_t duplex;
        uint8_t intr_lsc;
        uint16_t max_mtu;
+       size_t max_rx_pkt_len;
        /*
         * App management thread and virtio interrupt handler thread
         * both can change device state, this lock is meant to avoid

diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index 0568305..72d3dda 100644 (file)
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -841,6 +841,56 @@ virtio_dev_allmulticast_disable(struct rte_eth_dev *dev)
        return 0;
 }
 
+uint16_t
+virtio_rx_mem_pool_buf_size(struct rte_mempool *mp)
+{
+       return rte_pktmbuf_data_room_size(mp) - RTE_PKTMBUF_HEADROOM;
+}
+
+bool
+virtio_rx_check_scatter(uint16_t max_rx_pkt_len, uint16_t rx_buf_size,
+                       bool rx_scatter_enabled, const char **error)
+{
+       if (!rx_scatter_enabled && max_rx_pkt_len > rx_buf_size) {
+               *error = "Rx scatter is disabled and RxQ mbuf pool object size is too small";
+               return false;
+       }
+
+       return true;
+}
+
+static bool
+virtio_check_scatter_on_all_rx_queues(struct rte_eth_dev *dev,
+                                     uint16_t frame_size)
+{
+       struct virtio_hw *hw = dev->data->dev_private;
+       struct virtnet_rx *rxvq;
+       struct virtqueue *vq;
+       unsigned int qidx;
+       uint16_t buf_size;
+       const char *error;
+
+       if (hw->vqs == NULL)
+               return true;
+
+       for (qidx = 0; (vq = hw->vqs[2 * qidx + VTNET_SQ_RQ_QUEUE_IDX]) != NULL;
+            qidx++) {
+               rxvq = &vq->rxq;
+               if (rxvq->mpool == NULL)
+                       continue;
+               buf_size = virtio_rx_mem_pool_buf_size(rxvq->mpool);
+
+               if (!virtio_rx_check_scatter(frame_size, buf_size,
+                                            hw->rx_ol_scatter, &error)) {
+                       PMD_INIT_LOG(ERR, "MTU check for RxQ %u failed: %s",
+                                    qidx, error);
+                       return false;
+               }
+       }
+
+       return true;
+}
+
 #define VLAN_TAG_LEN           4    /* 802.3ac tag (not DMA'd) */
 static int
 virtio_mtu_set(struct rte_eth_dev *dev, uint16_t mtu)
@@ -858,6 +908,15 @@ virtio_mtu_set(struct rte_eth_dev *dev, uint16_t mtu)
                        RTE_ETHER_MIN_MTU, max_frame_size - ether_hdr_len);
                return -EINVAL;
        }
+
+       if (!virtio_check_scatter_on_all_rx_queues(dev, frame_size)) {
+               PMD_INIT_LOG(ERR, "MTU vs Rx scatter and Rx buffers check failed");
+               return -EINVAL;
+       }
+
+       hw->max_rx_pkt_len = frame_size;
+       dev->data->dev_conf.rxmode.max_rx_pkt_len = hw->max_rx_pkt_len;
+
        return 0;
 }
 
@@ -2042,6 +2101,8 @@ virtio_dev_configure(struct rte_eth_dev *dev)
        if (rxmode->max_rx_pkt_len > hw->max_mtu + ether_hdr_len)
                req_features &= ~(1ULL << VIRTIO_NET_F_MTU);
 
+       hw->max_rx_pkt_len = rxmode->max_rx_pkt_len;
+
        if (rx_offloads & (DEV_RX_OFFLOAD_UDP_CKSUM |
                           DEV_RX_OFFLOAD_TCP_CKSUM))
                req_features |= (1ULL << VIRTIO_NET_F_GUEST_CSUM);
@@ -2090,6 +2151,8 @@ virtio_dev_configure(struct rte_eth_dev *dev)
        if (rx_offloads & DEV_RX_OFFLOAD_VLAN_STRIP)
                hw->vlan_strip = 1;
 
+       hw->rx_ol_scatter = (rx_offloads & DEV_RX_OFFLOAD_SCATTER);
+
        if ((rx_offloads & DEV_RX_OFFLOAD_VLAN_FILTER) &&
                        !virtio_with_feature(hw, VIRTIO_NET_F_CTRL_VLAN)) {
                PMD_DRV_LOG(ERR,
@@ -2445,6 +2508,8 @@ virtio_dev_info_get(struct rte_eth_dev *dev, struct rte_eth_dev_info *dev_info)
        host_features = VIRTIO_OPS(hw)->get_features(hw);
        dev_info->rx_offload_capa = DEV_RX_OFFLOAD_VLAN_STRIP;
        dev_info->rx_offload_capa |= DEV_RX_OFFLOAD_JUMBO_FRAME;
+       if (host_features & (1ULL << VIRTIO_NET_F_MRG_RXBUF))
+               dev_info->rx_offload_capa |= DEV_RX_OFFLOAD_SCATTER;
        if (host_features & (1ULL << VIRTIO_NET_F_GUEST_CSUM)) {
                dev_info->rx_offload_capa |=
                        DEV_RX_OFFLOAD_TCP_CKSUM |

diff --git a/drivers/net/virtio/virtio_ethdev.h b/drivers/net/virtio/virtio_ethdev.h
index 5a501e7..2f63ef2 100644 (file)
--- a/drivers/net/virtio/virtio_ethdev.h
+++ b/drivers/net/virtio/virtio_ethdev.h
@@ -120,4 +120,9 @@ int virtio_dev_close(struct rte_eth_dev *dev);
 int virtio_inject_pkts(struct rte_eth_dev *dev, struct rte_mbuf **tx_pkts,
                int nb_pkts);
 
+bool virtio_rx_check_scatter(uint16_t max_rx_pkt_len, uint16_t rx_buf_size,
+                       bool rx_scatter_enabled, const char **error);
+
+uint16_t virtio_rx_mem_pool_buf_size(struct rte_mempool *mp);
+
 #endif /* _VIRTIO_ETHDEV_H_ */

diff --git a/drivers/net/virtio/virtio_rxtx.c b/drivers/net/virtio/virtio_rxtx.c
index f70644b..d0365ce 100644 (file)
--- a/drivers/net/virtio/virtio_rxtx.c
+++ b/drivers/net/virtio/virtio_rxtx.c
@@ -666,6 +666,8 @@ virtio_dev_rx_queue_setup(struct rte_eth_dev *dev,
        struct virtqueue *vq = hw->vqs[vq_idx];
        struct virtnet_rx *rxvq;
        uint16_t rx_free_thresh;
+       uint16_t buf_size;
+       const char *error;
 
        PMD_INIT_FUNC_TRACE();
 
@@ -674,6 +676,14 @@ virtio_dev_rx_queue_setup(struct rte_eth_dev *dev,
                return -EINVAL;
        }
 
+       buf_size = virtio_rx_mem_pool_buf_size(mp);
+       if (!virtio_rx_check_scatter(hw->max_rx_pkt_len, buf_size,
+                                    hw->rx_ol_scatter, &error)) {
+               PMD_INIT_LOG(ERR, "RxQ %u Rx scatter check failed: %s",
+                            queue_idx, error);
+               return -EINVAL;
+       }
+
        rx_free_thresh = rx_conf->rx_free_thresh;
        if (rx_free_thresh == 0)
                rx_free_thresh =