tap: Remove tap_probe_vnet_hdr_len()

It was necessary since an Linux older than 2.6.35 may implement the
virtio-net header but may not allow to change its length. Remove it
since such an old Linux is no longer supported.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>

1 files changed, 2 insertions, 6 deletions

diff --git a/net/tap.c b/net/tap.c
index baaa2f7a9a..72ae95894f 100644
--- a/net/tap.c
+++ b/net/tap.c
@@ -259,11 +259,7 @@ static bool tap_has_vnet_hdr(NetClientState *nc)
 
 static bool tap_has_vnet_hdr_len(NetClientState *nc, int len)
 {
-    TAPState *s = DO_UPCAST(TAPState, nc, nc);
-
-    assert(nc->info->type == NET_CLIENT_DRIVER_TAP);
-
-    return !!tap_probe_vnet_hdr_len(s->fd, len);
+    return tap_has_vnet_hdr(nc);
 }
 
 static int tap_get_vnet_hdr_len(NetClientState *nc)
@@ -432,7 +428,7 @@ static TAPState *net_tap_fd_init(NetClientState *peer,
      * Make sure host header length is set correctly in tap:
      * it might have been modified by another instance of qemu.
      */
-    if (tap_probe_vnet_hdr_len(s->fd, s->host_vnet_hdr_len)) {
+    if (vnet_hdr) {
         tap_fd_set_vnet_hdr_len(s->fd, s->host_vnet_hdr_len);
     }
     tap_read_poll(s, true);