Re: [PATCH v2 12/20] net/tap: net_init_tap_one(): support bridge

[Vladimir Sementsov-Ogievskiy]

On 03.09.25 08:28, Jason Wang wrote:

On Sun, Aug 24, 2025 at 12:03 AM Vladimir Sementsov-Ogievskiy
<vsement...@yandex-team.ru> wrote:

Use net_init_tap_one() in net_init_bridge().

Need to explain why this is needed.

Oh, right. It took a minute for me to remember)

Will add:

To be able in further commits use net_init_bridge for "bridge" case of init_tap,
as it almost the same, but requires tap-related things in net_init_tap_one.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@yandex-team.ru>
---
  net/tap.c | 28 +++++++++++++++++++++++-----
  1 file changed, 23 insertions(+), 5 deletions(-)

diff --git a/net/tap.c b/net/tap.c
index 468dae7004..5acfb128a1 100644
--- a/net/tap.c
+++ b/net/tap.c
@@ -88,6 +88,12 @@ static void launch_script(const char *setup_script, const 
char *ifname,
  static void tap_send(void *opaque);
  static void tap_writable(void *opaque);

+static int net_init_tap_one(const Netdev *netdev, NetClientState *peer,
+                            const char *model, const char *name,
+                            const char *ifname, const char *script,
+                            const char *downscript, const char *vhostfdname,
+                            int vnet_hdr, int fd, Error **errp);
+
  static void tap_update_fd_handler(TAPState *s)
  {
      qemu_set_fd_handler(s->fd,
@@ -626,8 +632,7 @@ int net_init_bridge(const Netdev *netdev, const char *name,
  {
      const NetdevBridgeOptions *bridge;
      const char *helper, *br;
-    TAPState *s;
-    int fd, vnet_hdr;
+    int fd, vnet_hdr, ret;

      assert(netdev->type == NET_CLIENT_DRIVER_BRIDGE);
      bridge = &netdev->u.bridge;
@@ -648,9 +653,14 @@ int net_init_bridge(const Netdev *netdev, const char *name,
          close(fd);
          return -1;
      }
-    s = net_tap_fd_init(peer, "bridge", name, fd, vnet_hdr);

-    qemu_set_info_str(&s->nc, "helper=%s,br=%s", helper, br);
+    ret = net_init_tap_one(netdev, peer, "bridge", name,
+                           NULL, NULL, NULL,
+                           NULL, vnet_hdr, fd, errp);
+    if (ret < 0) {
+        close(fd);
+        return -1;
+    }

      return 0;
  }
@@ -698,11 +708,19 @@ static int net_init_tap_one(const Netdev *netdev, 
NetClientState *peer,
                              const char *downscript, const char *vhostfdname,
                              int vnet_hdr, int fd, Error **errp)
  {
-    const NetdevTapOptions *tap = &netdev->u.tap;
+    const NetdevTapOptions *tap;
      TAPState *s = net_tap_fd_init(peer, model, name, fd, vnet_hdr);
      int vhostfd;

+    if (netdev->type == NET_CLIENT_DRIVER_BRIDGE) {
+        const NetdevBridgeOptions *bridge = &netdev->u.bridge;
+        qemu_set_info_str(&s->nc, "helper=%s,br=%s",
+                          bridge->helper, bridge->br);
+        return 0;
+    }
+
      assert(netdev->type == NET_CLIENT_DRIVER_TAP);
+    tap = &netdev->u.tap;

      if (tap_set_sndbuf(s->fd, tap, errp) < 0) {
          goto failed;
--
2.48.1

--
Best regards,
Vladimir