[Qemu-devel] [ RFC Patch v6 3/3] virtio-net rsc: add 2 new rsc information fields to 'virtio_net_hdr'

[wexu@redhat.com]

From: Wei Xu <wexu@redhat.com>

Field 'coalesced' is to indicate how many packets are coalesced and field
'dup_ack' is how many duplicate acks are merged, guest driver can use these
information to notify what's the exact scene of original traffic over the
networks.

Signed-off-by: Wei Xu <wexu@redhat.com>
---
 hw/net/virtio-net.c                         | 8 ++++++++
 include/standard-headers/linux/virtio_net.h | 2 ++
 2 files changed, 10 insertions(+)

diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index cc8cbe4..20f552a 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -1768,6 +1768,10 @@ static size_t virtio_net_rsc_drain_seg(NetRscChain *chain, NetRscSeg *seg)
     if ((chain->proto == ETH_P_IP) && seg->is_coalesced) {
         virtio_net_rsc_ipv4_checksum(h, seg->unit.ip);
     }
+    h->coalesced = seg->packets;
+    h->dup_ack = seg->dup_ack;
+    h->gso_type = chain->gso_type;
+    h->gso_size = chain->max_payload;
     ret = virtio_net_do_receive(seg->nc, seg->buf, seg->size);
     QTAILQ_REMOVE(&chain->buffers, seg, next);
     g_free(seg->buf);
@@ -2302,9 +2306,13 @@ static ssize_t virtio_net_receive(NetClientState *nc,
                                   const uint8_t *buf, size_t size)
 {
     VirtIONet *n;
+    struct virtio_net_hdr *h;
 
     n = qemu_get_nic_opaque(nc);
     if (n->host_features & (1ULL << VIRTIO_NET_F_GUEST_RSC)) {
+        h = (struct virtio_net_hdr *)buf;
+        h->coalesced = 0;
+        h->dup_ack = 0;
         return virtio_net_rsc_receive(nc, buf, size);
     } else {
         return virtio_net_do_receive(nc, buf, size);
diff --git a/include/standard-headers/linux/virtio_net.h b/include/standard-headers/linux/virtio_net.h
index 5b95762..c837417 100644
--- a/include/standard-headers/linux/virtio_net.h
+++ b/include/standard-headers/linux/virtio_net.h
@@ -114,6 +114,8 @@ struct virtio_net_hdr {
 	__virtio16 gso_size;		/* Bytes to append to hdr_len per frame */
 	__virtio16 csum_start;	/* Position to start checksumming from */
 	__virtio16 csum_offset;	/* Offset after that to place checksum */
+    __virtio16 coalesced;   /* packets coalesced by host */
+    __virtio16 dup_ack;     /* duplicate ack count */
 };
 
 /* This is the version of the header to use when the MRG_RXBUF
-- 
2.7.1