Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

---

 net.c           |    8 ++++++++

 net/tap.c       |   29 +++++++++++++++++++++++++++++

 qemu-options.hx |    4 +++-

 3 files changed, 40 insertions(+), 1 deletions(-)

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

index 6ef93e6..b942d03 100644

--- a/net.c

+++ b/net.c

@@ -976,6 +976,14 @@ static struct {

                 .name = "vnet_hdr",

                 .type = QEMU_OPT_BOOL,

                 .help = "enable the IFF_VNET_HDR flag on the tap interface"

+            }, {

+                .name = "vhost",

+                .type = QEMU_OPT_BOOL,

+                .help = "enable vhost-net network accelerator",

+            }, {

+                .name = "vhostfd",

+                .type = QEMU_OPT_STRING,

+                .help = "file descriptor of an already opened vhost net device",

             },

 #endif /* _WIN32 */

             { /* end of list */ }

diff --git a/net/tap.c b/net/tap.c

index 7e9ca79..d9f2e41 100644

--- a/net/tap.c

+++ b/net/tap.c

@@ -41,6 +41,8 @@

 #include "net/tap-linux.h"

+#include "hw/vhost_net.h"

+

 /* Maximum GSO packet size (64k) plus plenty of room for

  * the ethernet and virtio_net headers

  */

@@ -57,6 +59,7 @@ typedef struct TAPState {

     unsigned int has_vnet_hdr : 1;

     unsigned int using_vnet_hdr : 1;

     unsigned int has_ufo: 1;

+    struct vhost_net *vhost_net;

 } TAPState;

 static int launch_script(const char *setup_script, const char *ifname, int fd);

@@ -252,6 +255,10 @@ static void tap_cleanup(VLANClientState *nc)

 {

     TAPState *s = DO_UPCAST(TAPState, nc, nc);

+    if (s->vhost_net) {

+        vhost_net_cleanup(s->vhost_net);

+    }

+

     qemu_purge_queued_packets(nc);

     if (s->down_script[0])

@@ -307,6 +314,7 @@ static TAPState *net_tap_fd_init(VLANState *vlan,

     s->has_ufo = tap_probe_has_ufo(s->fd);

     tap_set_offload(&s->nc, 0, 0, 0, 0, 0);

     tap_read_poll(s, 1);

+    s->vhost_net = NULL;

     return s;

 }

@@ -456,6 +464,27 @@ int net_init_tap(QemuOpts *opts, Monitor *mon, const char *name, VLANState *vlan

         }

     }

+    if (qemu_opt_get_bool(opts, "vhost", 0)) {

+        int vhostfd, r;

+        if (qemu_opt_get(opts, "vhostfd")) {

+            r = net_handle_fd_param(mon, qemu_opt_get(opts, "vhostfd"));

+            if (r == -1) {

+                return -1;

+            }

+            vhostfd = r;

+        } else {

+            vhostfd = -1;

+        }

+        s->vhost_net = vhost_net_init(&s->nc, vhostfd);

+        if (!s->vhost_net) {

+            qemu_error("vhost-net requested but could not be initialized\n");

+            return -1;

+        }

+    } else if (qemu_opt_get(opts, "vhostfd")) {

+        qemu_error("vhostfd= is not valid without vhost\n");

+        return -1;

+    }

+

     if (vlan) {

         vlan->nb_host_devs++;

     }

diff --git a/qemu-options.hx b/qemu-options.hx

index ca73ba5..2b3d9b8 100644

--- a/qemu-options.hx

+++ b/qemu-options.hx

@@ -814,7 +814,7 @@ DEF("net", HAS_ARG, QEMU_OPTION_net,

     "-net tap[,vlan=n][,name=str],ifname=name\n"

     "                connect the host TAP network interface to VLAN 'n'\n"

 #else

-    "-net tap[,vlan=n][,name=str][,fd=h][,ifname=name][,script=file][,downscript=dfile][,sndbuf=nbytes][,vnet_hdr=on|off]\n"

+    "-net tap[,vlan=n][,name=str][,fd=h][,ifname=name][,script=file][,downscript=dfile][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off][,vhostfd=h]\n"

     "                connect the host TAP network interface to VLAN 'n' and use the\n"

     "                network scripts 'file' (default=%s)\n"

     "                and 'dfile' (default=%s);\n"

@@ -824,6 +824,8 @@ DEF("net", HAS_ARG, QEMU_OPTION_net,

     "                default of 'sndbuf=1048576' can be disabled using 'sndbuf=0'\n"

     "                use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag; use\n"

     "                vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"

+    "                use vhost=on to enable experimental in kernel accelerator\n"

+    "                use 'vhostfd=h' to connect to an already opened vhost net device\n"

 #endif

     "-net socket[,vlan=n][,name=str][,fd=h][,listen=[host]:port][,connect=host:port]\n"

     "                connect the vlan 'n' to another VLAN using a socket connection\n"

-- 

1.6.6.144.g5c3af