Merge tag 'net-pull-request' of https://github.com/jasowang/qemu into staging

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* tag 'net-pull-request' of https://github.com/jasowang/qemu:
  net/passt: Implement vhost-user backend support
  net: Add passt network backend
  net: Add is_vhost_user flag to vhost_net struct
  net: Allow network backends to advertise max TX queue size
  net: Add save_acked_features callback to vhost_net
  net: Add get_acked_features callback to VhostNetOptions
  net: Consolidate vhost feature bits into vhost_net structure
  net: Add get_vhost_net callback to NetClientInfo
  vhost_net: Rename vhost_set_vring_enable() for clarity
  net: Define net_client_set_link()
  net: Refactor stream logic for reuse in '-net passt'
  virtio-net: Add queues for RSS during migration
  net: fix buffer overflow in af_xdp_umem_create()

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

1 files changed, 36 insertions, 7 deletions

diff --git a/net/tap.c b/net/tap.c
index ae1c7e3983..23536c09b4 100644
--- a/net/tap.c
+++ b/net/tap.c
@@ -42,11 +42,29 @@
 #include "qemu/error-report.h"
 #include "qemu/main-loop.h"
 #include "qemu/sockets.h"
+#include "hw/virtio/vhost.h"
 
 #include "net/tap.h"
 
 #include "net/vhost_net.h"
 
+static const int kernel_feature_bits[] = {
+    VIRTIO_F_NOTIFY_ON_EMPTY,
+    VIRTIO_RING_F_INDIRECT_DESC,
+    VIRTIO_RING_F_EVENT_IDX,
+    VIRTIO_NET_F_MRG_RXBUF,
+    VIRTIO_F_VERSION_1,
+    VIRTIO_NET_F_MTU,
+    VIRTIO_F_IOMMU_PLATFORM,
+    VIRTIO_F_RING_PACKED,
+    VIRTIO_F_RING_RESET,
+    VIRTIO_F_IN_ORDER,
+    VIRTIO_F_NOTIFICATION_DATA,
+    VIRTIO_NET_F_RSC_EXT,
+    VIRTIO_NET_F_HASH_REPORT,
+    VHOST_INVALID_FEATURE_BIT
+};
+
 typedef struct TAPState {
     NetClientState nc;
     int fd;
@@ -329,6 +347,18 @@ int tap_get_fd(NetClientState *nc)
     return s->fd;
 }
 
+/*
+ * tap_get_vhost_net() can return NULL if a tap net-device backend is
+ * created with 'vhost=off' option, 'vhostforce=off' or no vhost or
+ * vhostforce or vhostfd options at all. Please see net_init_tap_one().
+ */
+static VHostNetState *tap_get_vhost_net(NetClientState *nc)
+{
+    TAPState *s = DO_UPCAST(TAPState, nc, nc);
+    assert(nc->info->type == NET_CLIENT_DRIVER_TAP);
+    return s->vhost_net;
+}
+
 /* fd support */
 
 static NetClientInfo net_tap_info = {
@@ -347,6 +377,7 @@ static NetClientInfo net_tap_info = {
     .set_vnet_le = tap_set_vnet_le,
     .set_vnet_be = tap_set_vnet_be,
     .set_steering_ebpf = tap_set_steering_ebpf,
+    .get_vhost_net = tap_get_vhost_net,
 };
 
 static TAPState *net_tap_fd_init(NetClientState *peer,
@@ -712,6 +743,11 @@ static void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer,
         }
         options.opaque = (void *)(uintptr_t)vhostfd;
         options.nvqs = 2;
+        options.feature_bits = kernel_feature_bits;
+        options.get_acked_features = NULL;
+        options.save_acked_features = NULL;
+        options.max_tx_queue_size = 0;
+        options.is_vhost_user = false;
 
         s->vhost_net = vhost_net_init(&options);
         if (!s->vhost_net) {
@@ -980,13 +1016,6 @@ free_fail:
     return 0;
 }
 
-VHostNetState *tap_get_vhost_net(NetClientState *nc)
-{
-    TAPState *s = DO_UPCAST(TAPState, nc, nc);
-    assert(nc->info->type == NET_CLIENT_DRIVER_TAP);
-    return s->vhost_net;
-}
-
 int tap_enable(NetClientState *nc)
 {
     TAPState *s = DO_UPCAST(TAPState, nc, nc);