Re: [PATCH v2 4/4] virtio-net: Add support for USO features

[Akihiko Odaki]

On 2023/08/01 7:31, Yuri Benditovich wrote:

USO features of virtio-net device depend on kernel ability
to support them, for backward compatibility by default the
features are disabled on 8.0 and earlier.

Signed-off-by: Yuri Benditovich <yuri.benditov...@daynix.com>
Signed-off-by: Andrew Melnychecnko <and...@daynix.com>
---
  hw/core/machine.c   |  4 ++++
  hw/net/virtio-net.c | 31 +++++++++++++++++++++++++++++--
  2 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/hw/core/machine.c b/hw/core/machine.c
index f0d35c6401..a725e76738 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -38,10 +38,14 @@
  #include "exec/confidential-guest-support.h"
  #include "hw/virtio/virtio.h"
  #include "hw/virtio/virtio-pci.h"
+#include "hw/virtio/virtio-net.h"

GlobalProperty hw_compat_8_0[] = {

      { "migration", "multifd-flush-after-each-section", "on"},
      { TYPE_PCI_DEVICE, "x-pcie-ari-nextfn-1", "on" },
+    { TYPE_VIRTIO_NET, "host_uso", "off"},
+    { TYPE_VIRTIO_NET, "guest_uso4", "off"},
+    { TYPE_VIRTIO_NET, "guest_uso6", "off"},

Nitpick: Add a whitespace before closing brackets '}'.

  };
  const size_t hw_compat_8_0_len = G_N_ELEMENTS(hw_compat_8_0);

diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c

index d2311e7d6e..bd0ead94fe 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -659,6 +659,15 @@ static int peer_has_ufo(VirtIONet *n)
      return n->has_ufo;
  }

+static int peer_has_uso(VirtIONet *n)

+{
+    if (!peer_has_vnet_hdr(n)) {
+        return 0;
+    }
+
+    return qemu_has_uso(qemu_get_queue(n->nic)->peer);
+}
+
  static void virtio_net_set_mrg_rx_bufs(VirtIONet *n, int mergeable_rx_bufs,
                                         int version_1, int hash_report)
  {
@@ -796,6 +805,10 @@ static uint64_t virtio_net_get_features(VirtIODevice 
*vdev, uint64_t features,
          virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_TSO6);
          virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_ECN);

+ virtio_clear_feature(&features, VIRTIO_NET_F_HOST_USO);

+        virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_USO4);
+        virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_USO6);
+
          virtio_clear_feature(&features, VIRTIO_NET_F_HASH_REPORT);
      }

@@ -804,6 +817,12 @@ static uint64_t virtio_net_get_features(VirtIODevice *vdev, uint64_t features,

          virtio_clear_feature(&features, VIRTIO_NET_F_HOST_UFO);
      }

+ if (!peer_has_uso(n)) {

+        virtio_clear_feature(&features, VIRTIO_NET_F_HOST_USO);
+        virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_USO4);
+        virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_USO6);
+    }
+
      if (!get_vhost_net(nc->peer)) {
          return features;
      }
@@ -864,14 +883,16 @@ static void virtio_net_apply_guest_offloads(VirtIONet *n)
              !!(n->curr_guest_offloads & (1ULL << VIRTIO_NET_F_GUEST_USO6)));
  }

-static uint64_t virtio_net_guest_offloads_by_features(uint32_t features)

+static uint64_t virtio_net_guest_offloads_by_features(uint64_t features)
  {
      static const uint64_t guest_offloads_mask =
          (1ULL << VIRTIO_NET_F_GUEST_CSUM) |
          (1ULL << VIRTIO_NET_F_GUEST_TSO4) |
          (1ULL << VIRTIO_NET_F_GUEST_TSO6) |
          (1ULL << VIRTIO_NET_F_GUEST_ECN)  |
-        (1ULL << VIRTIO_NET_F_GUEST_UFO);
+        (1ULL << VIRTIO_NET_F_GUEST_UFO)  |
+        (1ULL << VIRTIO_NET_F_GUEST_USO4) |
+        (1ULL << VIRTIO_NET_F_GUEST_USO6);

return guest_offloads_mask & features;

  }
@@ -3924,6 +3945,12 @@ static Property virtio_net_properties[] = {
      DEFINE_PROP_INT32("speed", VirtIONet, net_conf.speed, SPEED_UNKNOWN),
      DEFINE_PROP_STRING("duplex", VirtIONet, net_conf.duplex_str),
      DEFINE_PROP_BOOL("failover", VirtIONet, failover, false),
+    DEFINE_PROP_BIT64("guest_uso4", VirtIONet, host_features,
+                      VIRTIO_NET_F_GUEST_USO4, true),
+    DEFINE_PROP_BIT64("guest_uso6", VirtIONet, host_features,
+                      VIRTIO_NET_F_GUEST_USO6, true),
+    DEFINE_PROP_BIT64("host_uso", VirtIONet, host_features,
+                      VIRTIO_NET_F_HOST_USO, true),
      DEFINE_PROP_END_OF_LIST(),
  };