vhost: support UDP Fragmentation Offload

In virtio, UDP Fragmentation Offload (UFO) includes two parts: host UFO
and guest UFO. Guest UFO means the frontend can receive large UDP
packets, and host UFO means the backend can receive large UDP packets.
This patch supports host UFO and guest UFO for vhost-user.

Signed-off-by: Jiayu Hu <jiayu.hu@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Tested-by: Lei Yao <lei.a.yao@intel.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Yuanhan Liu <yliu@fridaylinux.org>

diff --git a/lib/librte_mbuf/rte_mbuf.h b/lib/librte_mbuf/rte_mbuf.h
index e4e3917..6cba632 100644 (file)
--- a/lib/librte_mbuf/rte_mbuf.h
+++ b/lib/librte_mbuf/rte_mbuf.h
@@ -208,6 +208,13 @@ extern "C" {
 
 /* add new TX flags here */
 
+/**
+ * UDP Fragmentation Offload flag. This flag is used for enabling UDP
+ * fragmentation in SW or in HW. When use UFO, mbuf->tso_segsz is used
+ * to store the MSS of UDP fragments.
+ */
+#define PKT_TX_UDP_SEG (1ULL << 42)
+
 /**
  * Request security offload processing on the TX packet.
  */

diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h
index 1943d06..8afb426 100644 (file)
--- a/lib/librte_vhost/vhost.h
+++ b/lib/librte_vhost/vhost.h
@@ -178,10 +178,12 @@ struct vhost_msg {
                                (1ULL << VIRTIO_NET_F_GSO) | \
                                (1ULL << VIRTIO_NET_F_HOST_TSO4) | \
                                (1ULL << VIRTIO_NET_F_HOST_TSO6) | \
+                               (1ULL << VIRTIO_NET_F_HOST_UFO) | \
                                (1ULL << VIRTIO_NET_F_CSUM)    | \
                                (1ULL << VIRTIO_NET_F_GUEST_CSUM) | \
                                (1ULL << VIRTIO_NET_F_GUEST_TSO4) | \
                                (1ULL << VIRTIO_NET_F_GUEST_TSO6) | \
+                               (1ULL << VIRTIO_NET_F_GUEST_UFO) | \
                                (1ULL << VIRTIO_RING_F_INDIRECT_DESC) | \
                                (1ULL << VIRTIO_NET_F_MTU) | \
                                (1ULL << VIRTIO_F_IOMMU_PLATFORM))

diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c
index 4f7217f..cd304f6 100644 (file)
--- a/lib/librte_vhost/virtio_net.c
+++ b/lib/librte_vhost/virtio_net.c
@@ -159,6 +159,11 @@ virtio_enqueue_offload(struct rte_mbuf *m_buf, struct virtio_net_hdr *net_hdr)
                net_hdr->gso_size = m_buf->tso_segsz;
                net_hdr->hdr_len = m_buf->l2_len + m_buf->l3_len
                                        + m_buf->l4_len;
+       } else if (m_buf->ol_flags & PKT_TX_UDP_SEG) {
+               net_hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP;
+               net_hdr->gso_size = m_buf->tso_segsz;
+               net_hdr->hdr_len = m_buf->l2_len + m_buf->l3_len +
+                       m_buf->l4_len;
        } else {
                ASSIGN_UNLESS_EQUAL(net_hdr->gso_type, 0);
                ASSIGN_UNLESS_EQUAL(net_hdr->gso_size, 0);
@@ -792,6 +797,11 @@ vhost_dequeue_offload(struct virtio_net_hdr *hdr, struct rte_mbuf *m)
                        m->tso_segsz = hdr->gso_size;
                        m->l4_len = (tcp_hdr->data_off & 0xf0) >> 2;
                        break;
+               case VIRTIO_NET_HDR_GSO_UDP:
+                       m->ol_flags |= PKT_TX_UDP_SEG;
+                       m->tso_segsz = hdr->gso_size;
+                       m->l4_len = sizeof(struct udp_hdr);
+                       break;
                default:
                        RTE_LOG(WARNING, VHOST_DATA,
                                "unsupported gso type %u.\n", hdr->gso_type);