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

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# gpg: Signature made Fri 28 Oct 2022 01:29:25 EDT
# gpg:                using RSA key EF04965B398D6211
# gpg: Good signature from "Jason Wang (Jason Wang on RedHat) <jasowang@redhat.com>" [full]
# Primary key fingerprint: 215D 46F4 8246 689E C77F  3562 EF04 965B 398D 6211

* tag 'net-pull-request' of https://github.com/jasowang/qemu: (26 commits)
  net: stream: add QAPI events to report connection state
  net: stream: move to QIO to enable additional parameters
  qemu-sockets: update socket_uri() and socket_parse() to be consistent
  qemu-sockets: move and rename SocketAddress_to_str()
  net: dgram: add unix socket
  net: dgram: move mcast specific code from net_socket_fd_init_dgram()
  net: dgram: make dgram_dst generic
  net: stream: add unix socket
  net: stream: Don't ignore EINVAL on netdev socket connection
  net: socket: Don't ignore EINVAL on netdev socket connection
  qapi: net: add stream and dgram netdevs
  net: introduce qemu_set_info_str() function
  qapi: net: introduce a way to bypass qemu_opts_parse_noisily()
  net: simplify net_client_parse() error management
  net: remove the @errp argument of net_client_inits()
  net: introduce convert_host_port()
  vhost: Accept event idx flag
  vhost: use avail event idx on vhost_svq_kick
  vhost: toggle device callbacks using used event idx
  vhost: allocate event_idx fields on vring
  ...

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

25 files changed, 1473 insertions, 210 deletions

diff --git a/hmp-commands.hx b/hmp-commands.hx
index 12b6d4e..673e39a 100644
--- a/hmp-commands.hx
+++ b/hmp-commands.hx
@@ -1276,7 +1276,7 @@ ERST
     {
         .name       = "netdev_add",
         .args_type  = "netdev:O",
-        .params     = "[user|tap|socket|vde|bridge|hubport|netmap|vhost-user"
+        .params     = "[user|tap|socket|stream|dgram|vde|bridge|hubport|netmap|vhost-user"
 #ifdef CONFIG_VMNET
                       "|vmnet-host|vmnet-shared|vmnet-bridged"
 #endif
diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index e9f696b..b6903ae 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -2526,6 +2526,7 @@ static void virtio_net_tx_complete(NetClientState *nc, ssize_t len)
     VirtIONet *n = qemu_get_nic_opaque(nc);
     VirtIONetQueue *q = virtio_net_get_subqueue(nc);
     VirtIODevice *vdev = VIRTIO_DEVICE(n);
+    int ret;
 
     virtqueue_push(q->tx_vq, q->async_tx.elem, 0);
     virtio_notify(vdev, q->tx_vq);
@@ -2534,7 +2535,22 @@ static void virtio_net_tx_complete(NetClientState *nc, ssize_t len)
     q->async_tx.elem = NULL;
 
     virtio_queue_set_notification(q->tx_vq, 1);
-    virtio_net_flush_tx(q);
+    ret = virtio_net_flush_tx(q);
+    if (ret >= n->tx_burst) {
+        /*
+         * the flush has been stopped by tx_burst
+         * we will not receive notification for the
+         * remainining part, so re-schedule
+         */
+        virtio_queue_set_notification(q->tx_vq, 0);
+        if (q->tx_bh) {
+            qemu_bh_schedule(q->tx_bh);
+        } else {
+            timer_mod(q->tx_timer,
+                      qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + n->tx_timeout);
+        }
+        q->tx_waiting = 1;
+    }
 }
 
 /* TX */
@@ -2633,6 +2649,8 @@ drop:
     return num_packets;
 }
 
+static void virtio_net_tx_timer(void *opaque);
+
 static void virtio_net_handle_tx_timer(VirtIODevice *vdev, VirtQueue *vq)
 {
     VirtIONet *n = VIRTIO_NET(vdev);
@@ -2650,15 +2668,13 @@ static void virtio_net_handle_tx_timer(VirtIODevice *vdev, VirtQueue *vq)
     }
 
     if (q->tx_waiting) {
-        virtio_queue_set_notification(vq, 1);
+        /* We already have queued packets, immediately flush */
         timer_del(q->tx_timer);
-        q->tx_waiting = 0;
-        if (virtio_net_flush_tx(q) == -EINVAL) {
-            return;
-        }
+        virtio_net_tx_timer(q);
     } else {
+        /* re-arm timer to flush it (and more) on next tick */
         timer_mod(q->tx_timer,
-                       qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + n->tx_timeout);
+                  qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + n->tx_timeout);
         q->tx_waiting = 1;
         virtio_queue_set_notification(vq, 0);
     }
@@ -2691,6 +2707,8 @@ static void virtio_net_tx_timer(void *opaque)
     VirtIONetQueue *q = opaque;
     VirtIONet *n = q->n;
     VirtIODevice *vdev = VIRTIO_DEVICE(n);
+    int ret;
+
     /* This happens when device was stopped but BH wasn't. */
     if (!vdev->vm_running) {
         /* Make sure tx waiting is set, so we'll run when restarted. */
@@ -2705,8 +2723,33 @@ static void virtio_net_tx_timer(void *opaque)
         return;
     }
 
+    ret = virtio_net_flush_tx(q);
+    if (ret == -EBUSY || ret == -EINVAL) {
+        return;
+    }
+    /*
+     * If we flush a full burst of packets, assume there are
+     * more coming and immediately rearm
+     */
+    if (ret >= n->tx_burst) {
+        q->tx_waiting = 1;
+        timer_mod(q->tx_timer,
+                  qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + n->tx_timeout);
+        return;
+    }
+    /*
+     * If less than a full burst, re-enable notification and flush
+     * anything that may have come in while we weren't looking.  If
+     * we find something, assume the guest is still active and rearm
+     */
     virtio_queue_set_notification(q->tx_vq, 1);
-    virtio_net_flush_tx(q);
+    ret = virtio_net_flush_tx(q);
+    if (ret > 0) {
+        virtio_queue_set_notification(q->tx_vq, 0);
+        q->tx_waiting = 1;
+        timer_mod(q->tx_timer,
+                  qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + n->tx_timeout);
+    }
 }
 
 static void virtio_net_tx_bh(void *opaque)
diff --git a/hw/net/xen_nic.c b/hw/net/xen_nic.c
index 5c815b4..7d92c2d 100644
--- a/hw/net/xen_nic.c
+++ b/hw/net/xen_nic.c
@@ -296,9 +296,8 @@ static int net_init(struct XenLegacyDevice *xendev)
     netdev->nic = qemu_new_nic(&net_xen_info, &netdev->conf,
                                "xen", NULL, netdev);
 
-    snprintf(qemu_get_queue(netdev->nic)->info_str,
-             sizeof(qemu_get_queue(netdev->nic)->info_str),
-             "nic: xenbus vif macaddr=%s", netdev->mac);
+    qemu_set_info_str(qemu_get_queue(netdev->nic),
+                      "nic: xenbus vif macaddr=%s", netdev->mac);
 
     /* fill info */
     xenstore_write_be_int(&netdev->xendev, "feature-rx-copy", 1);
diff --git a/hw/virtio/vhost-shadow-virtqueue.c b/hw/virtio/vhost-shadow-virtqueue.c
index 596d443..5bd14ca 100644
--- a/hw/virtio/vhost-shadow-virtqueue.c
+++ b/hw/virtio/vhost-shadow-virtqueue.c
@@ -33,6 +33,7 @@ bool vhost_svq_valid_features(uint64_t features, Error **errp)
          ++b) {
         switch (b) {
         case VIRTIO_F_ANY_LAYOUT:
+        case VIRTIO_RING_F_EVENT_IDX:
             continue;
 
         case VIRTIO_F_ACCESS_PLATFORM:
@@ -218,12 +219,22 @@ static bool vhost_svq_add_split(VhostShadowVirtqueue *svq,
 
 static void vhost_svq_kick(VhostShadowVirtqueue *svq)
 {
+    bool needs_kick;
+
     /*
      * We need to expose the available array entries before checking the used
      * flags
      */
     smp_mb();
-    if (svq->vring.used->flags & VRING_USED_F_NO_NOTIFY) {
+
+    if (virtio_vdev_has_feature(svq->vdev, VIRTIO_RING_F_EVENT_IDX)) {
+        uint16_t avail_event = *(uint16_t *)(&svq->vring.used->ring[svq->vring.num]);
+        needs_kick = vring_need_event(avail_event, svq->shadow_avail_idx, svq->shadow_avail_idx - 1);
+    } else {
+        needs_kick = !(svq->vring.used->flags & VRING_USED_F_NO_NOTIFY);
+    }
+
+    if (!needs_kick) {
         return;
     }
 
@@ -369,15 +380,27 @@ static bool vhost_svq_more_used(VhostShadowVirtqueue *svq)
  */
 static bool vhost_svq_enable_notification(VhostShadowVirtqueue *svq)
 {
-    svq->vring.avail->flags &= ~cpu_to_le16(VRING_AVAIL_F_NO_INTERRUPT);
-    /* Make sure the flag is written before the read of used_idx */
+    if (virtio_vdev_has_feature(svq->vdev, VIRTIO_RING_F_EVENT_IDX)) {
+        uint16_t *used_event = (uint16_t *)&svq->vring.avail->ring[svq->vring.num];
+        *used_event = svq->shadow_used_idx;
+    } else {
+        svq->vring.avail->flags &= ~cpu_to_le16(VRING_AVAIL_F_NO_INTERRUPT);
+    }
+
+    /* Make sure the event is enabled before the read of used_idx */
     smp_mb();
     return !vhost_svq_more_used(svq);
 }
 
 static void vhost_svq_disable_notification(VhostShadowVirtqueue *svq)
 {
-    svq->vring.avail->flags |= cpu_to_le16(VRING_AVAIL_F_NO_INTERRUPT);
+    /*
+     * No need to disable notification in the event idx case, since used event
+     * index is already an index too far away.
+     */
+    if (!virtio_vdev_has_feature(svq->vdev, VIRTIO_RING_F_EVENT_IDX)) {
+        svq->vring.avail->flags |= cpu_to_le16(VRING_AVAIL_F_NO_INTERRUPT);
+    }
 }
 
 static uint16_t vhost_svq_last_desc_of_chain(const VhostShadowVirtqueue *svq,
@@ -570,16 +593,16 @@ void vhost_svq_get_vring_addr(const VhostShadowVirtqueue *svq,
 size_t vhost_svq_driver_area_size(const VhostShadowVirtqueue *svq)
 {
     size_t desc_size = sizeof(vring_desc_t) * svq->vring.num;
-    size_t avail_size = offsetof(vring_avail_t, ring) +
-                                             sizeof(uint16_t) * svq->vring.num;
+    size_t avail_size = offsetof(vring_avail_t, ring[svq->vring.num]) +
+                                                              sizeof(uint16_t);
 
     return ROUND_UP(desc_size + avail_size, qemu_real_host_page_size());
 }
 
 size_t vhost_svq_device_area_size(const VhostShadowVirtqueue *svq)
 {
-    size_t used_size = offsetof(vring_used_t, ring) +
-                                    sizeof(vring_used_elem_t) * svq->vring.num;
+    size_t used_size = offsetof(vring_used_t, ring[svq->vring.num]) +
+                                                              sizeof(uint16_t);
     return ROUND_UP(used_size, qemu_real_host_page_size());
 }
 
diff --git a/include/net/net.h b/include/net/net.h
index 81d0b21..3db75ff 100644
--- a/include/net/net.h
+++ b/include/net/net.h
@@ -177,6 +177,7 @@ ssize_t qemu_send_packet_async(NetClientState *nc, const uint8_t *buf,
 void qemu_purge_queued_packets(NetClientState *nc);
 void qemu_flush_queued_packets(NetClientState *nc);
 void qemu_flush_or_purge_queued_packets(NetClientState *nc, bool purge);
+void qemu_set_info_str(NetClientState *nc, const char *fmt, ...);
 void qemu_format_nic_info_str(NetClientState *nc, uint8_t macaddr[6]);
 bool qemu_has_ufo(NetClientState *nc);
 bool qemu_has_vnet_hdr(NetClientState *nc);
@@ -220,9 +221,11 @@ extern NICInfo nd_table[MAX_NICS];
 extern const char *host_net_devices[];
 
 /* from net.c */
-int net_client_parse(QemuOptsList *opts_list, const char *str);
+bool netdev_is_modern(const char *optarg);
+void netdev_parse_modern(const char *optarg);
+void net_client_parse(QemuOptsList *opts_list, const char *str);
 void show_netdevs(void);
-int net_init_clients(Error **errp);
+void net_init_clients(void);
 void net_check_clients(void);
 void net_cleanup(void);
 void hmp_host_net_add(Monitor *mon, const QDict *qdict);
diff --git a/include/qemu/sockets.h b/include/qemu/sockets.h
index 036745e..214058d 100644
--- a/include/qemu/sockets.h
+++ b/include/qemu/sockets.h
@@ -58,6 +58,7 @@ NetworkAddressFamily inet_netfamily(int family);
 int unix_listen(const char *path, Error **errp);
 int unix_connect(const char *path, Error **errp);
 
+char *socket_uri(SocketAddress *addr);
 SocketAddress *socket_parse(const char *str, Error **errp);
 int socket_connect(SocketAddress *addr, Error **errp);
 int socket_listen(SocketAddress *addr, int num, Error **errp);
@@ -65,6 +66,8 @@ void socket_listen_cleanup(int fd, Error **errp);
 int socket_dgram(SocketAddress *remote, SocketAddress *local, Error **errp);
 
 /* Old, ipv4 only bits.  Don't use for new code. */
+int convert_host_port(struct sockaddr_in *saddr, const char *host,
+                      const char *port, Error **errp);
 int parse_host_port(struct sockaddr_in *saddr, const char *str,
                     Error **errp);
 int socket_init(void);
@@ -139,5 +142,4 @@ SocketAddress *socket_address_flatten(SocketAddressLegacy *addr);
  * Return 0 on success.
  */
 int socket_address_parse_named_fd(SocketAddress *addr, Error **errp);
-
 #endif /* QEMU_SOCKETS_H */
diff --git a/monitor/hmp-cmds.c b/monitor/hmp-cmds.c
index bab86c5..01b789a 100644
--- a/monitor/hmp-cmds.c
+++ b/monitor/hmp-cmds.c
@@ -199,27 +199,6 @@ void hmp_info_mice(Monitor *mon, const QDict *qdict)
     qapi_free_MouseInfoList(mice_list);
 }
 
-static char *SocketAddress_to_str(SocketAddress *addr)
-{
-    switch (addr->type) {
-    case SOCKET_ADDRESS_TYPE_INET:
-        return g_strdup_printf("tcp:%s:%s",
-                               addr->u.inet.host,
-                               addr->u.inet.port);
-    case SOCKET_ADDRESS_TYPE_UNIX:
-        return g_strdup_printf("unix:%s",
-                               addr->u.q_unix.path);
-    case SOCKET_ADDRESS_TYPE_FD:
-        return g_strdup_printf("fd:%s", addr->u.fd.str);
-    case SOCKET_ADDRESS_TYPE_VSOCK:
-        return g_strdup_printf("tcp:%s:%s",
-                               addr->u.vsock.cid,
-                               addr->u.vsock.port);
-    default:
-        return g_strdup("unknown address type");
-    }
-}
-
 void hmp_info_migrate(Monitor *mon, const QDict *qdict)
 {
     MigrationInfo *info;
@@ -382,7 +361,7 @@ void hmp_info_migrate(Monitor *mon, const QDict *qdict)
         monitor_printf(mon, "socket address: [\n");
 
         for (addr = info->socket_address; addr; addr = addr->next) {
-            char *s = SocketAddress_to_str(addr->value);
+            char *s = socket_uri(addr->value);
             monitor_printf(mon, "\t%s\n", s);
             g_free(s);
         }
diff --git a/net/clients.h b/net/clients.h
index c915778..ed8bdff 100644
--- a/net/clients.h
+++ b/net/clients.h
@@ -40,6 +40,12 @@ int net_init_hubport(const Netdev *netdev, const char *name,
 int net_init_socket(const Netdev *netdev, const char *name,
                     NetClientState *peer, Error **errp);
 
+int net_init_stream(const Netdev *netdev, const char *name,
+                    NetClientState *peer, Error **errp);
+
+int net_init_dgram(const Netdev *netdev, const char *name,
+                   NetClientState *peer, Error **errp);
+
 int net_init_tap(const Netdev *netdev, const char *name,
                  NetClientState *peer, Error **errp);
 
diff --git a/net/dgram.c b/net/dgram.c
new file mode 100644
index 0000000..9f7bf38
--- /dev/null
+++ b/net/dgram.c
@@ -0,0 +1,623 @@
+/*
+ * QEMU System Emulator
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ * Copyright (c) 2022 Red Hat, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "qemu/osdep.h"
+
+#include "net/net.h"
+#include "clients.h"
+#include "monitor/monitor.h"
+#include "qapi/error.h"
+#include "qemu/error-report.h"
+#include "qemu/option.h"
+#include "qemu/sockets.h"
+#include "qemu/iov.h"
+#include "qemu/main-loop.h"
+#include "qemu/cutils.h"
+
+typedef struct NetDgramState {
+    NetClientState nc;
+    int fd;
+    SocketReadState rs;
+    bool read_poll;               /* waiting to receive data? */
+    bool write_poll;              /* waiting to transmit data? */
+    /* contains destination iff connectionless */
+    struct sockaddr *dest_addr;
+    socklen_t dest_len;
+} NetDgramState;
+
+static void net_dgram_send(void *opaque);
+static void net_dgram_writable(void *opaque);
+
+static void net_dgram_update_fd_handler(NetDgramState *s)
+{
+    qemu_set_fd_handler(s->fd,
+                        s->read_poll ? net_dgram_send : NULL,
+                        s->write_poll ? net_dgram_writable : NULL,
+                        s);
+}
+
+static void net_dgram_read_poll(NetDgramState *s, bool enable)
+{
+    s->read_poll = enable;
+    net_dgram_update_fd_handler(s);
+}
+
+static void net_dgram_write_poll(NetDgramState *s, bool enable)
+{
+    s->write_poll = enable;
+    net_dgram_update_fd_handler(s);
+}
+
+static void net_dgram_writable(void *opaque)
+{
+    NetDgramState *s = opaque;
+
+    net_dgram_write_poll(s, false);
+
+    qemu_flush_queued_packets(&s->nc);
+}
+
+static ssize_t net_dgram_receive(NetClientState *nc,
+                                 const uint8_t *buf, size_t size)
+{
+    NetDgramState *s = DO_UPCAST(NetDgramState, nc, nc);
+    ssize_t ret;
+
+    do {
+        if (s->dest_addr) {
+            ret = sendto(s->fd, buf, size, 0, s->dest_addr, s->dest_len);
+        } else {
+            ret = send(s->fd, buf, size, 0);
+        }
+    } while (ret == -1 && errno == EINTR);
+
+    if (ret == -1 && errno == EAGAIN) {
+        net_dgram_write_poll(s, true);
+        return 0;
+    }
+    return ret;
+}
+
+static void net_dgram_send_completed(NetClientState *nc, ssize_t len)
+{
+    NetDgramState *s = DO_UPCAST(NetDgramState, nc, nc);
+
+    if (!s->read_poll) {
+        net_dgram_read_poll(s, true);
+    }
+}
+
+static void net_dgram_rs_finalize(SocketReadState *rs)
+{
+    NetDgramState *s = container_of(rs, NetDgramState, rs);
+
+    if (qemu_send_packet_async(&s->nc, rs->buf,
+                               rs->packet_len,
+                               net_dgram_send_completed) == 0) {
+        net_dgram_read_poll(s, false);
+    }
+}
+
+static void net_dgram_send(void *opaque)
+{
+    NetDgramState *s = opaque;
+    int size;
+
+    size = recv(s->fd, s->rs.buf, sizeof(s->rs.buf), 0);
+    if (size < 0) {
+        return;
+    }
+    if (size == 0) {
+        /* end of connection */
+        net_dgram_read_poll(s, false);
+        net_dgram_write_poll(s, false);
+        return;
+    }
+    if (qemu_send_packet_async(&s->nc, s->rs.buf, size,
+                               net_dgram_send_completed) == 0) {
+        net_dgram_read_poll(s, false);
+    }
+}
+
+static int net_dgram_mcast_create(struct sockaddr_in *mcastaddr,
+                                  struct in_addr *localaddr,
+                                  Error **errp)
+{
+    struct ip_mreq imr;
+    int fd;
+    int val, ret;
+#ifdef __OpenBSD__
+    unsigned char loop;
+#else
+    int loop;
+#endif
+
+    if (!IN_MULTICAST(ntohl(mcastaddr->sin_addr.s_addr))) {
+        error_setg(errp, "specified mcastaddr %s (0x%08x) "
+                   "does not contain a multicast address",
+                   inet_ntoa(mcastaddr->sin_addr),
+                   (int)ntohl(mcastaddr->sin_addr.s_addr));
+        return -1;
+    }
+
+    fd = qemu_socket(PF_INET, SOCK_DGRAM, 0);
+    if (fd < 0) {
+        error_setg_errno(errp, errno, "can't create datagram socket");
+        return -1;
+    }
+
+    /*
+     * Allow multiple sockets to bind the same multicast ip and port by setting
+     * SO_REUSEADDR. This is the only situation where SO_REUSEADDR should be set
+     * on windows. Use socket_set_fast_reuse otherwise as it sets SO_REUSEADDR
+     * only on posix systems.
+     */
+    val = 1;
+    ret = setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
+    if (ret < 0) {
+        error_setg_errno(errp, errno, "can't set socket option SO_REUSEADDR");
+        goto fail;
+    }
+
+    ret = bind(fd, (struct sockaddr *)mcastaddr, sizeof(*mcastaddr));
+    if (ret < 0) {
+        error_setg_errno(errp, errno, "can't bind ip=%s to socket",
+                         inet_ntoa(mcastaddr->sin_addr));
+        goto fail;
+    }
+
+    /* Add host to multicast group */
+    imr.imr_multiaddr = mcastaddr->sin_addr;
+    if (localaddr) {
+        imr.imr_interface = *localaddr;
+    } else {
+        imr.imr_interface.s_addr = htonl(INADDR_ANY);
+    }
+
+    ret = setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP,
+                     &imr, sizeof(struct ip_mreq));
+    if (ret < 0) {
+        error_setg_errno(errp, errno,
+                         "can't add socket to multicast group %s",
+                         inet_ntoa(imr.imr_multiaddr));
+        goto fail;
+    }
+
+    /* Force mcast msgs to loopback (eg. several QEMUs in same host */
+    loop = 1;
+    ret = setsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP,
+                     &loop, sizeof(loop));
+    if (ret < 0) {
+        error_setg_errno(errp, errno,
+                         "can't force multicast message to loopback");
+        goto fail;
+    }
+
+    /* If a bind address is given, only send packets from that address */
+    if (localaddr != NULL) {
+        ret = setsockopt(fd, IPPROTO_IP, IP_MULTICAST_IF,
+                         localaddr, sizeof(*localaddr));
+        if (ret < 0) {
+            error_setg_errno(errp, errno,
+                             "can't set the default network send interface");
+            goto fail;
+        }
+    }
+
+    qemu_socket_set_nonblock(fd);
+    return fd;
+fail:
+    if (fd >= 0) {
+        closesocket(fd);
+    }
+    return -1;
+}
+
+static void net_dgram_cleanup(NetClientState *nc)
+{
+    NetDgramState *s = DO_UPCAST(NetDgramState, nc, nc);
+    if (s->fd != -1) {
+        net_dgram_read_poll(s, false);
+        net_dgram_write_poll(s, false);
+        close(s->fd);
+        s->fd = -1;
+    }
+    g_free(s->dest_addr);
+    s->dest_addr = NULL;
+    s->dest_len = 0;
+}
+
+static NetClientInfo net_dgram_socket_info = {
+    .type = NET_CLIENT_DRIVER_DGRAM,
+    .size = sizeof(NetDgramState),
+    .receive = net_dgram_receive,
+    .cleanup = net_dgram_cleanup,
+};
+
+static NetDgramState *net_dgram_fd_init(NetClientState *peer,
+                                        const char *model,
+                                        const char *name,
+                                        int fd,
+                                        Error **errp)
+{
+    NetClientState *nc;
+    NetDgramState *s;
+
+    nc = qemu_new_net_client(&net_dgram_socket_info, peer, model, name);
+
+    s = DO_UPCAST(NetDgramState, nc, nc);
+
+    s->fd = fd;
+    net_socket_rs_init(&s->rs, net_dgram_rs_finalize, false);
+    net_dgram_read_poll(s, true);
+
+    return s;
+}
+
+static int net_dgram_mcast_init(NetClientState *peer,
+                                const char *model,
+                                const char *name,
+                                SocketAddress *remote,
+                                SocketAddress *local,
+                                Error **errp)
+{
+    NetDgramState *s;
+    int fd, ret;
+    struct sockaddr_in *saddr;
+
+    if (remote->type != SOCKET_ADDRESS_TYPE_INET) {
+        error_setg(errp, "multicast only support inet type");
+        return -1;
+    }
+
+    saddr = g_new(struct sockaddr_in, 1);
+    if (convert_host_port(saddr, remote->u.inet.host, remote->u.inet.port,
+                          errp) < 0) {
+        g_free(saddr);
+        return -1;
+    }
+
+    if (!local) {
+        fd = net_dgram_mcast_create(saddr, NULL, errp);
+        if (fd < 0) {
+            g_free(saddr);
+            return -1;
+        }
+    } else {
+        switch (local->type) {
+        case SOCKET_ADDRESS_TYPE_INET: {
+            struct in_addr localaddr;
+
+            if (inet_aton(local->u.inet.host, &localaddr) == 0) {
+                g_free(saddr);
+                error_setg(errp, "localaddr '%s' is not a valid IPv4 address",
+                           local->u.inet.host);
+                return -1;
+            }
+
+            fd = net_dgram_mcast_create(saddr, &localaddr, errp);
+            if (fd < 0) {
+                g_free(saddr);
+                return -1;
+            }
+            break;
+        }
+        case SOCKET_ADDRESS_TYPE_FD: {
+            int newfd;
+
+            fd = monitor_fd_param(monitor_cur(), local->u.fd.str, errp);
+            if (fd == -1) {
+                g_free(saddr);
+                return -1;
+            }
+            ret = qemu_socket_try_set_nonblock(fd);
+            if (ret < 0) {
+                g_free(saddr);
+                error_setg_errno(errp, -ret, "%s: Can't use file descriptor %d",
+                                 name, fd);
+                return -1;
+            }
+
+            /*
+             * fd passed: multicast: "learn" dest_addr address from bound
+             * address and save it. Because this may be "shared" socket from a
+             * "master" process, datagrams would be recv() by ONLY ONE process:
+             * we must "clone" this dgram socket --jjo
+             */
+
+            saddr = g_new(struct sockaddr_in, 1);
+
+            if (convert_host_port(saddr, local->u.inet.host, local->u.inet.port,
+                                  errp) < 0) {
+                g_free(saddr);
+                closesocket(fd);
+                return -1;
+            }
+
+            /* must be bound */
+            if (saddr->sin_addr.s_addr == 0) {
+                error_setg(errp, "can't setup multicast destination address");
+                g_free(saddr);
+                closesocket(fd);
+                return -1;
+            }
+            /* clone dgram socket */
+            newfd = net_dgram_mcast_create(saddr, NULL, errp);
+            if (newfd < 0) {
+                g_free(saddr);
+                closesocket(fd);
+                return -1;
+            }
+            /* clone newfd to fd, close newfd */
+            dup2(newfd, fd);
+            close(newfd);
+            break;
+        }
+        default:
+            g_free(saddr);
+            error_setg(errp, "only support inet or fd type for local");
+            return -1;
+        }
+    }
+
+    s = net_dgram_fd_init(peer, model, name, fd, errp);
+    if (!s) {
+        g_free(saddr);
+        return -1;
+    }
+
+    g_assert(s->dest_addr == NULL);
+    s->dest_addr = (struct sockaddr *)saddr;
+    s->dest_len = sizeof(*saddr);
+
+    if (!local) {
+        qemu_set_info_str(&s->nc, "mcast=%s:%d",
+                          inet_ntoa(saddr->sin_addr),
+                          ntohs(saddr->sin_port));
+    } else {
+        switch (local->type) {
+        case SOCKET_ADDRESS_TYPE_INET:
+            qemu_set_info_str(&s->nc, "mcast=%s:%d",
+                              inet_ntoa(saddr->sin_addr),
+                              ntohs(saddr->sin_port));
+            break;
+        case SOCKET_ADDRESS_TYPE_FD:
+            qemu_set_info_str(&s->nc, "fd=%d (cloned mcast=%s:%d)",
+                              fd, inet_ntoa(saddr->sin_addr),
+                              ntohs(saddr->sin_port));
+            break;
+        default:
+            g_assert_not_reached();
+        }
+    }
+
+    return 0;
+
+}
+
+
+int net_init_dgram(const Netdev *netdev, const char *name,
+                   NetClientState *peer, Error **errp)
+{
+    NetDgramState *s;
+    int fd, ret;
+    SocketAddress *remote, *local;
+    struct sockaddr *dest_addr;
+    struct sockaddr_in laddr_in, raddr_in;
+    struct sockaddr_un laddr_un, raddr_un;
+    socklen_t dest_len;
+
+    assert(netdev->type == NET_CLIENT_DRIVER_DGRAM);
+
+    remote = netdev->u.dgram.remote;
+    local = netdev->u.dgram.local;
+
+    /* detect multicast address */
+    if (remote && remote->type == SOCKET_ADDRESS_TYPE_INET) {
+        struct sockaddr_in mcastaddr;
+
+        if (convert_host_port(&mcastaddr, remote->u.inet.host,
+                              remote->u.inet.port, errp) < 0) {
+            return -1;
+        }
+
+        if (IN_MULTICAST(ntohl(mcastaddr.sin_addr.s_addr))) {
+            return net_dgram_mcast_init(peer, "dram", name, remote, local,
+                                           errp);
+        }
+    }
+
+    /* unicast address */
+    if (!local) {
+        error_setg(errp, "dgram requires local= parameter");
+        return -1;
+    }
+
+    if (remote) {
+        if (local->type == SOCKET_ADDRESS_TYPE_FD) {
+            error_setg(errp, "don't set remote with local.fd");
+            return -1;
+        }
+        if (remote->type != local->type) {
+            error_setg(errp, "remote and local types must be the same");
+            return -1;
+        }
+    } else {
+        if (local->type != SOCKET_ADDRESS_TYPE_FD) {
+            error_setg(errp,
+                       "type=inet or type=unix requires remote parameter");
+            return -1;
+        }
+    }
+
+    switch (local->type) {
+    case SOCKET_ADDRESS_TYPE_INET:
+        if (convert_host_port(&laddr_in, local->u.inet.host, local->u.inet.port,
+                              errp) < 0) {
+            return -1;
+        }
+
+        if (convert_host_port(&raddr_in, remote->u.inet.host,
+                              remote->u.inet.port, errp) < 0) {
+            return -1;
+        }
+
+        fd = qemu_socket(PF_INET, SOCK_DGRAM, 0);
+        if (fd < 0) {
+            error_setg_errno(errp, errno, "can't create datagram socket");
+            return -1;
+        }
+
+        ret = socket_set_fast_reuse(fd);
+        if (ret < 0) {
+            error_setg_errno(errp, errno,
+                             "can't set socket option SO_REUSEADDR");
+            closesocket(fd);
+            return -1;
+        }
+        ret = bind(fd, (struct sockaddr *)&laddr_in, sizeof(laddr_in));
+        if (ret < 0) {
+            error_setg_errno(errp, errno, "can't bind ip=%s to socket",
+                             inet_ntoa(laddr_in.sin_addr));
+            closesocket(fd);
+            return -1;
+        }
+        qemu_socket_set_nonblock(fd);
+
+        dest_len = sizeof(raddr_in);
+        dest_addr = g_malloc(dest_len);
+        memcpy(dest_addr, &raddr_in, dest_len);
+        break;
+    case SOCKET_ADDRESS_TYPE_UNIX:
+        ret = unlink(local->u.q_unix.path);
+        if (ret < 0 && errno != ENOENT) {
+            error_setg_errno(errp, errno, "failed to unlink socket %s",
+                             local->u.q_unix.path);
+            return -1;
+        }
+
+        laddr_un.sun_family = PF_UNIX;
+        ret = snprintf(laddr_un.sun_path, sizeof(laddr_un.sun_path), "%s",
+                       local->u.q_unix.path);
+        if (ret < 0 || ret >= sizeof(laddr_un.sun_path)) {
+            error_setg(errp, "UNIX socket path '%s' is too long",
+                       local->u.q_unix.path);
+            error_append_hint(errp, "Path must be less than %zu bytes\n",
+                              sizeof(laddr_un.sun_path));
+        }
+
+        raddr_un.sun_family = PF_UNIX;
+        ret = snprintf(raddr_un.sun_path, sizeof(raddr_un.sun_path), "%s",
+                       remote->u.q_unix.path);
+        if (ret < 0 || ret >= sizeof(raddr_un.sun_path)) {
+            error_setg(errp, "UNIX socket path '%s' is too long",
+                       remote->u.q_unix.path);
+            error_append_hint(errp, "Path must be less than %zu bytes\n",
+                              sizeof(raddr_un.sun_path));
+        }
+
+        fd = qemu_socket(PF_UNIX, SOCK_DGRAM, 0);
+        if (fd < 0) {
+            error_setg_errno(errp, errno, "can't create datagram socket");
+            return -1;
+        }
+
+        ret = bind(fd, (struct sockaddr *)&laddr_un, sizeof(laddr_un));
+        if (ret < 0) {
+            error_setg_errno(errp, errno, "can't bind unix=%s to socket",
+                             laddr_un.sun_path);
+            closesocket(fd);
+            return -1;
+        }
+        qemu_socket_set_nonblock(fd);
+
+        dest_len = sizeof(raddr_un);
+        dest_addr = g_malloc(dest_len);
+        memcpy(dest_addr, &raddr_un, dest_len);
+        break;
+    case SOCKET_ADDRESS_TYPE_FD:
+        fd = monitor_fd_param(monitor_cur(), local->u.fd.str, errp);
+        if (fd == -1) {
+            return -1;
+        }
+        ret = qemu_socket_try_set_nonblock(fd);
+        if (ret < 0) {
+            error_setg_errno(errp, -ret, "%s: Can't use file descriptor %d",
+                             name, fd);
+            return -1;
+        }
+        dest_addr = NULL;
+        dest_len = 0;
+        break;
+    default:
+        error_setg(errp, "only support inet or fd type for local");
+        return -1;
+    }
+
+    s = net_dgram_fd_init(peer, "dgram", name, fd, errp);
+    if (!s) {
+        return -1;
+    }
+
+    if (remote) {
+        g_assert(s->dest_addr == NULL);
+        s->dest_addr = dest_addr;
+        s->dest_len = dest_len;
+    }
+
+    switch (local->type) {
+    case SOCKET_ADDRESS_TYPE_INET:
+        qemu_set_info_str(&s->nc, "udp=%s:%d/%s:%d",
+                          inet_ntoa(laddr_in.sin_addr),
+                          ntohs(laddr_in.sin_port),
+                          inet_ntoa(raddr_in.sin_addr),
+                          ntohs(raddr_in.sin_port));
+        break;
+    case SOCKET_ADDRESS_TYPE_UNIX:
+        qemu_set_info_str(&s->nc, "udp=%s:%s",
+                          laddr_un.sun_path, raddr_un.sun_path);
+        break;
+    case SOCKET_ADDRESS_TYPE_FD: {
+        SocketAddress *sa;
+        SocketAddressType sa_type;
+
+        sa = socket_local_address(fd, errp);
+        if (sa) {
+            sa_type = sa->type;
+            qapi_free_SocketAddress(sa);
+
+            qemu_set_info_str(&s->nc, "fd=%d %s", fd,
+                              SocketAddressType_str(sa_type));
+        } else {
+            qemu_set_info_str(&s->nc, "fd=%d", fd);
+        }
+        break;
+    }
+    default:
+        g_assert_not_reached();
+    }
+
+    return 0;
+}
diff --git a/net/hub.c b/net/hub.c
index 1375738..67ca534 100644
--- a/net/hub.c
+++ b/net/hub.c
@@ -313,6 +313,8 @@ void net_hub_check_clients(void)
             case NET_CLIENT_DRIVER_USER:
             case NET_CLIENT_DRIVER_TAP:
             case NET_CLIENT_DRIVER_SOCKET:
+            case NET_CLIENT_DRIVER_STREAM:
+            case NET_CLIENT_DRIVER_DGRAM:
             case NET_CLIENT_DRIVER_VDE:
             case NET_CLIENT_DRIVER_VHOST_USER:
                 has_host_dev = 1;
diff --git a/net/l2tpv3.c b/net/l2tpv3.c
index af373e5..350041a 100644
--- a/net/l2tpv3.c
+++ b/net/l2tpv3.c
@@ -723,8 +723,7 @@ int net_init_l2tpv3(const Netdev *netdev,
 
     l2tpv3_read_poll(s, true);
 
-    snprintf(s->nc.info_str, sizeof(s->nc.info_str),
-             "l2tpv3: connected");
+    qemu_set_info_str(&s->nc, "l2tpv3: connected");
     return 0;
 outerr:
     qemu_del_net_client(nc);
diff --git a/net/meson.build b/net/meson.build
index d1be76d..6cd1e3d 100644
--- a/net/meson.build
+++ b/net/meson.build
@@ -13,6 +13,8 @@ softmmu_ss.add(files(
   'net.c',
   'queue.c',
   'socket.c',
+  'stream.c',
+  'dgram.c',
   'util.c',
 ))
 
diff --git a/net/net.c b/net/net.c
index 2db160e..840ad9d 100644
--- a/net/net.c
+++ b/net/net.c
@@ -48,12 +48,14 @@
 #include "qemu/qemu-print.h"
 #include "qemu/main-loop.h"
 #include "qemu/option.h"
+#include "qemu/keyval.h"
 #include "qapi/error.h"
 #include "qapi/opts-visitor.h"
 #include "sysemu/runstate.h"
 #include "net/colo-compare.h"
 #include "net/filter.h"
 #include "qapi/string-output-visitor.h"
+#include "qapi/qobject-input-visitor.h"
 
 /* Net bridge is currently not supported for W32. */
 #if !defined(_WIN32)
@@ -63,58 +65,70 @@
 static VMChangeStateEntry *net_change_state_entry;
 static QTAILQ_HEAD(, NetClientState) net_clients;
 
+typedef struct NetdevQueueEntry {
+    Netdev *nd;
+    Location loc;
+    QSIMPLEQ_ENTRY(NetdevQueueEntry) entry;
+} NetdevQueueEntry;
+
+typedef QSIMPLEQ_HEAD(, NetdevQueueEntry) NetdevQueue;
+
+static NetdevQueue nd_queue = QSIMPLEQ_HEAD_INITIALIZER(nd_queue);
+
 /***********************************************************/
 /* network device redirectors */
 
-int parse_host_port(struct sockaddr_in *saddr, const char *str,
-                    Error **errp)
+int convert_host_port(struct sockaddr_in *saddr, const char *host,
+                      const char *port, Error **errp)
 {
-    gchar **substrings;
     struct hostent *he;
-    const char *addr, *p, *r;
-    int port, ret = 0;
+    const char *r;
+    long p;
 
     memset(saddr, 0, sizeof(*saddr));
 
-    substrings = g_strsplit(str, ":", 2);
-    if (!substrings || !substrings[0] || !substrings[1]) {
-        error_setg(errp, "host address '%s' doesn't contain ':' "
-                   "separating host from port", str);
-        ret = -1;
-        goto out;
-    }
-
-    addr = substrings[0];
-    p = substrings[1];
-
     saddr->sin_family = AF_INET;
-    if (addr[0] == '\0') {
+    if (host[0] == '\0') {
         saddr->sin_addr.s_addr = 0;
     } else {
-        if (qemu_isdigit(addr[0])) {
-            if (!inet_aton(addr, &saddr->sin_addr)) {
+        if (qemu_isdigit(host[0])) {
+            if (!inet_aton(host, &saddr->sin_addr)) {
                 error_setg(errp, "host address '%s' is not a valid "
-                           "IPv4 address", addr);
-                ret = -1;
-                goto out;
+                           "IPv4 address", host);
+                return -1;
             }
         } else {
-            he = gethostbyname(addr);
+            he = gethostbyname(host);
             if (he == NULL) {
-                error_setg(errp, "can't resolve host address '%s'", addr);
-                ret = -1;
-                goto out;
+                error_setg(errp, "can't resolve host address '%s'", host);
+                return -1;
             }
             saddr->sin_addr = *(struct in_addr *)he->h_addr;
         }
     }
-    port = strtol(p, (char **)&r, 0);
-    if (r == p) {
-        error_setg(errp, "port number '%s' is invalid", p);
+    if (qemu_strtol(port, &r, 0, &p) != 0) {
+        error_setg(errp, "port number '%s' is invalid", port);
+        return -1;
+    }
+    saddr->sin_port = htons(p);
+    return 0;
+}
+
+int parse_host_port(struct sockaddr_in *saddr, const char *str,
+                    Error **errp)
+{
+    gchar **substrings;
+    int ret;
+
+    substrings = g_strsplit(str, ":", 2);
+    if (!substrings || !substrings[0] || !substrings[1]) {
+        error_setg(errp, "host address '%s' doesn't contain ':' "
+                   "separating host from port", str);
         ret = -1;
         goto out;
     }
-    saddr->sin_port = htons(port);
+
+    ret = convert_host_port(saddr, substrings[0], substrings[1], errp);
 
 out:
     g_strfreev(substrings);
@@ -128,13 +142,20 @@ char *qemu_mac_strdup_printf(const uint8_t *macaddr)
                            macaddr[3], macaddr[4], macaddr[5]);
 }
 
+void qemu_set_info_str(NetClientState *nc, const char *fmt, ...)
+{
+    va_list ap;
+
+    va_start(ap, fmt);
+    vsnprintf(nc->info_str, sizeof(nc->info_str), fmt, ap);
+    va_end(ap);
+}
+
 void qemu_format_nic_info_str(NetClientState *nc, uint8_t macaddr[6])
 {
-    snprintf(nc->info_str, sizeof(nc->info_str),
-             "model=%s,macaddr=%02x:%02x:%02x:%02x:%02x:%02x",
-             nc->model,
-             macaddr[0], macaddr[1], macaddr[2],
-             macaddr[3], macaddr[4], macaddr[5]);
+    qemu_set_info_str(nc, "model=%s,macaddr=%02x:%02x:%02x:%02x:%02x:%02x",
+                      nc->model, macaddr[0], macaddr[1], macaddr[2],
+                      macaddr[3], macaddr[4], macaddr[5]);
 }
 
 static int mac_table[256] = {0};
@@ -1001,6 +1022,8 @@ static int (* const net_client_init_fun[NET_CLIENT_DRIVER__MAX])(
 #endif
         [NET_CLIENT_DRIVER_TAP]       = net_init_tap,
         [NET_CLIENT_DRIVER_SOCKET]    = net_init_socket,
+        [NET_CLIENT_DRIVER_STREAM]    = net_init_stream,
+        [NET_CLIENT_DRIVER_DGRAM]     = net_init_dgram,
 #ifdef CONFIG_VDE
         [NET_CLIENT_DRIVER_VDE]       = net_init_vde,
 #endif
@@ -1036,19 +1059,23 @@ static int net_client_init1(const Netdev *netdev, bool is_netdev, Error **errp)
     if (is_netdev) {
         if (netdev->type == NET_CLIENT_DRIVER_NIC ||
             !net_client_init_fun[netdev->type]) {
-            error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
-                       "a netdev backend type");
+            error_setg(errp, "network backend '%s' is not compiled into this binary",
+                       NetClientDriver_str(netdev->type));
             return -1;
         }
     } else {
         if (netdev->type == NET_CLIENT_DRIVER_NONE) {
             return 0; /* nothing to do */
         }
-        if (netdev->type == NET_CLIENT_DRIVER_HUBPORT ||
-            !net_client_init_fun[netdev->type]) {
-            error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
-                       "a net backend type (maybe it is not compiled "
-                       "into this binary)");
+        if (netdev->type == NET_CLIENT_DRIVER_HUBPORT) {
+            error_setg(errp, "network backend '%s' is only supported with -netdev/-nic",
+                       NetClientDriver_str(netdev->type));
+            return -1;
+        }
+
+        if (!net_client_init_fun[netdev->type]) {
+            error_setg(errp, "network backend '%s' is not compiled into this binary",
+                       NetClientDriver_str(netdev->type));
             return -1;
         }
 
@@ -1088,6 +1115,8 @@ void show_netdevs(void)
     int idx;
     const char *available_netdevs[] = {
         "socket",
+        "stream",
+        "dgram",
         "hubport",
         "tap",
 #ifdef CONFIG_SLIRP
@@ -1560,36 +1589,97 @@ out:
     return ret;
 }
 
-int net_init_clients(Error **errp)
+static void netdev_init_modern(void)
+{
+    while (!QSIMPLEQ_EMPTY(&nd_queue)) {
+        NetdevQueueEntry *nd = QSIMPLEQ_FIRST(&nd_queue);
+
+        QSIMPLEQ_REMOVE_HEAD(&nd_queue, entry);
+        loc_push_restore(&nd->loc);
+        net_client_init1(nd->nd, true, &error_fatal);
+        loc_pop(&nd->loc);
+        qapi_free_Netdev(nd->nd);
+        g_free(nd);
+    }
+}
+
+void net_init_clients(void)
 {
     net_change_state_entry =
         qemu_add_vm_change_state_handler(net_vm_change_state_handler, NULL);
 
     QTAILQ_INIT(&net_clients);
 
-    if (qemu_opts_foreach(qemu_find_opts("netdev"),
-                          net_init_netdev, NULL, errp)) {
-        return -1;
-    }
+    netdev_init_modern();
 
-    if (qemu_opts_foreach(qemu_find_opts("nic"), net_param_nic, NULL, errp)) {
-        return -1;
-    }
+    qemu_opts_foreach(qemu_find_opts("netdev"), net_init_netdev, NULL,
+                      &error_fatal);
 
-    if (qemu_opts_foreach(qemu_find_opts("net"), net_init_client, NULL, errp)) {
-        return -1;
+    qemu_opts_foreach(qemu_find_opts("nic"), net_param_nic, NULL,
+                      &error_fatal);
+
+    qemu_opts_foreach(qemu_find_opts("net"), net_init_client, NULL,
+                      &error_fatal);
+}
+
+/*
+ * Does this -netdev argument use modern rather than traditional syntax?
+ * Modern syntax is to be parsed with netdev_parse_modern().
+ * Traditional syntax is to be parsed with net_client_parse().
+ */
+bool netdev_is_modern(const char *optarg)
+{
+    QemuOpts *opts;
+    bool is_modern;
+    const char *type;
+    static QemuOptsList dummy_opts = {
+        .name = "netdev",
+        .implied_opt_name = "type",
+        .head = QTAILQ_HEAD_INITIALIZER(dummy_opts.head),
+        .desc = { { } },
+    };
+
+    if (optarg[0] == '{') {
+        /* This is JSON, which means it's modern syntax */
+        return true;
     }
 
-    return 0;
+    opts = qemu_opts_create(&dummy_opts, NULL, false, &error_abort);
+    qemu_opts_do_parse(opts, optarg, dummy_opts.implied_opt_name,
+                       &error_abort);
+    type = qemu_opt_get(opts, "type");
+    is_modern = !g_strcmp0(type, "stream") || !g_strcmp0(type, "dgram");
+
+    qemu_opts_reset(&dummy_opts);
+
+    return is_modern;
+}
+
+/*
+ * netdev_parse_modern() uses modern, more expressive syntax than
+ * net_client_parse(), but supports only the -netdev option.
+ * netdev_parse_modern() appends to @nd_queue, whereas net_client_parse()
+ * appends to @qemu_netdev_opts.
+ */
+void netdev_parse_modern(const char *optarg)
+{
+    Visitor *v;
+    NetdevQueueEntry *nd;
+
+    v = qobject_input_visitor_new_str(optarg, "type", &error_fatal);
+    nd = g_new(NetdevQueueEntry, 1);
+    visit_type_Netdev(v, NULL, &nd->nd, &error_fatal);
+    visit_free(v);
+    loc_save(&nd->loc);
+
+    QSIMPLEQ_INSERT_TAIL(&nd_queue, nd, entry);
 }
 
-int net_client_parse(QemuOptsList *opts_list, const char *optarg)
+void net_client_parse(QemuOptsList *opts_list, const char *optarg)
 {
     if (!qemu_opts_parse_noisily(opts_list, optarg, true)) {
-        return -1;
+        exit(1);
     }
-
-    return 0;
 }
 
 /* From FreeBSD */
diff --git a/net/slirp.c b/net/slirp.c
index 8679be6..14a8d59 100644
--- a/net/slirp.c
+++ b/net/slirp.c
@@ -611,9 +611,8 @@ static int net_slirp_init(NetClientState *peer, const char *model,
 
     nc = qemu_new_net_client(&net_slirp_info, peer, model, name);
 
-    snprintf(nc->info_str, sizeof(nc->info_str),
-             "net=%s,restrict=%s", inet_ntoa(net),
-             restricted ? "on" : "off");
+    qemu_set_info_str(nc, "net=%s,restrict=%s", inet_ntoa(net),
+                      restricted ? "on" : "off");
 
     s = DO_UPCAST(SlirpState, nc, nc);
 
diff --git a/net/socket.c b/net/socket.c
index bfd8596..4944bb7 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -179,7 +179,7 @@ static void net_socket_send(void *opaque)
         s->fd = -1;
         net_socket_rs_init(&s->rs, net_socket_rs_finalize, false);
         s->nc.link_down = true;
-        memset(s->nc.info_str, 0, sizeof(s->nc.info_str));
+        qemu_set_info_str(&s->nc, "");
 
         return;
     }
@@ -387,16 +387,15 @@ static NetSocketState *net_socket_fd_init_dgram(NetClientState *peer,
     /* mcast: save bound address as dst */
     if (is_connected && mcast != NULL) {
         s->dgram_dst = saddr;
-        snprintf(nc->info_str, sizeof(nc->info_str),
-                 "socket: fd=%d (cloned mcast=%s:%d)",
-                 fd, inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
+        qemu_set_info_str(nc, "socket: fd=%d (cloned mcast=%s:%d)", fd,
+                          inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
     } else {
         if (sa_type == SOCKET_ADDRESS_TYPE_UNIX) {
             s->dgram_dst.sin_family = AF_UNIX;
         }
 
-        snprintf(nc->info_str, sizeof(nc->info_str),
-                 "socket: fd=%d %s", fd, SocketAddressType_str(sa_type));
+        qemu_set_info_str(nc, "socket: fd=%d %s", fd,
+                          SocketAddressType_str(sa_type));
     }
 
     return s;
@@ -430,7 +429,7 @@ static NetSocketState *net_socket_fd_init_stream(NetClientState *peer,
 
     nc = qemu_new_net_client(&net_socket_info, peer, model, name);
 
-    snprintf(nc->info_str, sizeof(nc->info_str), "socket: fd=%d", fd);
+    qemu_set_info_str(nc, "socket: fd=%d", fd);
 
     s = DO_UPCAST(NetSocketState, nc, nc);
 
@@ -497,9 +496,8 @@ static void net_socket_accept(void *opaque)
     s->fd = fd;
     s->nc.link_down = false;
     net_socket_connect(s);
-    snprintf(s->nc.info_str, sizeof(s->nc.info_str),
-             "socket: connection from %s:%d",
-             inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
+    qemu_set_info_str(&s->nc, "socket: connection from %s:%d",
+                      inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
 }
 
 static int net_socket_listen_init(NetClientState *peer,
@@ -579,8 +577,7 @@ static int net_socket_connect_init(NetClientState *peer,
             if (errno == EINTR || errno == EWOULDBLOCK) {
                 /* continue */
             } else if (errno == EINPROGRESS ||
-                       errno == EALREADY ||
-                       errno == EINVAL) {
+                       errno == EALREADY) {
                 break;
             } else {
                 error_setg_errno(errp, errno, "can't connect socket");
@@ -597,9 +594,8 @@ static int net_socket_connect_init(NetClientState *peer,
         return -1;
     }
 
-    snprintf(s->nc.info_str, sizeof(s->nc.info_str),
-             "socket: connect to %s:%d",
-             inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
+    qemu_set_info_str(&s->nc, "socket: connect to %s:%d",
+                      inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
     return 0;
 }
 
@@ -642,9 +638,8 @@ static int net_socket_mcast_init(NetClientState *peer,
 
     s->dgram_dst = saddr;
 
-    snprintf(s->nc.info_str, sizeof(s->nc.info_str),
-             "socket: mcast=%s:%d",
-             inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
+    qemu_set_info_str(&s->nc, "socket: mcast=%s:%d",
+                      inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
     return 0;
 
 }
@@ -697,9 +692,8 @@ static int net_socket_udp_init(NetClientState *peer,
 
     s->dgram_dst = raddr;
 
-    snprintf(s->nc.info_str, sizeof(s->nc.info_str),
-             "socket: udp=%s:%d",
-             inet_ntoa(raddr.sin_addr), ntohs(raddr.sin_port));
+    qemu_set_info_str(&s->nc, "socket: udp=%s:%d", inet_ntoa(raddr.sin_addr),
+                      ntohs(raddr.sin_port));
     return 0;
 }
 
diff --git a/net/stream.c b/net/stream.c
new file mode 100644
index 0000000..53b7040
--- /dev/null
+++ b/net/stream.c
@@ -0,0 +1,386 @@
+/*
+ * QEMU System Emulator
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ * Copyright (c) 2022 Red Hat, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "qemu/osdep.h"
+
+#include "net/net.h"
+#include "clients.h"
+#include "monitor/monitor.h"
+#include "qapi/error.h"
+#include "qemu/error-report.h"
+#include "qemu/option.h"
+#include "qemu/sockets.h"
+#include "qemu/iov.h"
+#include "qemu/main-loop.h"
+#include "qemu/cutils.h"
+#include "io/channel.h"
+#include "io/channel-socket.h"
+#include "io/net-listener.h"
+#include "qapi/qapi-events-net.h"
+
+typedef struct NetStreamState {
+    NetClientState nc;
+    QIOChannel *listen_ioc;
+    QIONetListener *listener;
+    QIOChannel *ioc;
+    guint ioc_read_tag;
+    guint ioc_write_tag;
+    SocketReadState rs;
+    unsigned int send_index;      /* number of bytes sent*/
+} NetStreamState;
+
+static void net_stream_listen(QIONetListener *listener,
+                              QIOChannelSocket *cioc,
+                              void *opaque);
+
+static gboolean net_stream_writable(QIOChannel *ioc,
+                                    GIOCondition condition,
+                                    gpointer data)
+{
+    NetStreamState *s = data;
+
+    s->ioc_write_tag = 0;
+
+    qemu_flush_queued_packets(&s->nc);
+
+    return G_SOURCE_REMOVE;
+}
+
+static ssize_t net_stream_receive(NetClientState *nc, const uint8_t *buf,
+                                  size_t size)
+{
+    NetStreamState *s = DO_UPCAST(NetStreamState, nc, nc);
+    uint32_t len = htonl(size);
+    struct iovec iov[] = {
+        {
+            .iov_base = &len,
+            .iov_len  = sizeof(len),
+        }, {
+            .iov_base = (void *)buf,
+            .iov_len  = size,
+        },
+    };
+    struct iovec local_iov[2];
+    unsigned int nlocal_iov;
+    size_t remaining;
+    ssize_t ret;
+
+    remaining = iov_size(iov, 2) - s->send_index;
+    nlocal_iov = iov_copy(local_iov, 2, iov, 2, s->send_index, remaining);
+    ret = qio_channel_writev(s->ioc, local_iov, nlocal_iov, NULL);
+    if (ret == QIO_CHANNEL_ERR_BLOCK) {
+        ret = 0; /* handled further down */
+    }
+    if (ret == -1) {
+        s->send_index = 0;
+        return -errno;
+    }
+    if (ret < (ssize_t)remaining) {
+        s->send_index += ret;
+        s->ioc_write_tag = qio_channel_add_watch(s->ioc, G_IO_OUT,
+                                                 net_stream_writable, s, NULL);
+        return 0;
+    }
+    s->send_index = 0;
+    return size;
+}
+
+static gboolean net_stream_send(QIOChannel *ioc,
+                                GIOCondition condition,
+                                gpointer data);
+
+static void net_stream_send_completed(NetClientState *nc, ssize_t len)
+{
+    NetStreamState *s = DO_UPCAST(NetStreamState, nc, nc);
+
+    if (!s->ioc_read_tag) {
+        s->ioc_read_tag = qio_channel_add_watch(s->ioc, G_IO_IN,
+                                                net_stream_send, s, NULL);
+    }
+}
+
+static void net_stream_rs_finalize(SocketReadState *rs)
+{
+    NetStreamState *s = container_of(rs, NetStreamState, rs);
+
+    if (qemu_send_packet_async(&s->nc, rs->buf,
+                               rs->packet_len,
+                               net_stream_send_completed) == 0) {
+        if (s->ioc_read_tag) {
+            g_source_remove(s->ioc_read_tag);
+            s->ioc_read_tag = 0;
+        }
+    }
+}
+
+static gboolean net_stream_send(QIOChannel *ioc,
+                                GIOCondition condition,
+                                gpointer data)
+{
+    NetStreamState *s = data;
+    int size;
+    int ret;
+    char buf1[NET_BUFSIZE];
+    const char *buf;
+
+    size = qio_channel_read(s->ioc, buf1, sizeof(buf1), NULL);
+    if (size < 0) {
+        if (errno != EWOULDBLOCK) {
+            goto eoc;
+        }
+    } else if (size == 0) {
+        /* end of connection */
+    eoc:
+        s->ioc_read_tag = 0;
+        if (s->ioc_write_tag) {
+            g_source_remove(s->ioc_write_tag);
+            s->ioc_write_tag = 0;
+        }
+        if (s->listener) {
+            qio_net_listener_set_client_func(s->listener, net_stream_listen,
+                                             s, NULL);
+        }
+        object_unref(OBJECT(s->ioc));
+        s->ioc = NULL;
+
+        net_socket_rs_init(&s->rs, net_stream_rs_finalize, false);
+        s->nc.link_down = true;
+        qemu_set_info_str(&s->nc, "");
+
+        qapi_event_send_netdev_stream_disconnected(s->nc.name);
+
+        return G_SOURCE_REMOVE;
+    }
+    buf = buf1;
+
+    ret = net_fill_rstate(&s->rs, (const uint8_t *)buf, size);
+
+    if (ret == -1) {
+        goto eoc;
+    }
+
+    return G_SOURCE_CONTINUE;
+}
+
+static void net_stream_cleanup(NetClientState *nc)
+{
+    NetStreamState *s = DO_UPCAST(NetStreamState, nc, nc);
+    if (s->ioc) {
+        if (QIO_CHANNEL_SOCKET(s->ioc)->fd != -1) {
+            if (s->ioc_read_tag) {
+                g_source_remove(s->ioc_read_tag);
+                s->ioc_read_tag = 0;
+            }
+            if (s->ioc_write_tag) {
+                g_source_remove(s->ioc_write_tag);
+                s->ioc_write_tag = 0;
+            }
+        }
+        object_unref(OBJECT(s->ioc));
+        s->ioc = NULL;
+    }
+    if (s->listen_ioc) {
+        if (s->listener) {
+            qio_net_listener_disconnect(s->listener);
+            object_unref(OBJECT(s->listener));
+            s->listener = NULL;
+        }
+        object_unref(OBJECT(s->listen_ioc));
+        s->listen_ioc = NULL;
+    }
+}
+
+static NetClientInfo net_stream_info = {
+    .type = NET_CLIENT_DRIVER_STREAM,
+    .size = sizeof(NetStreamState),
+    .receive = net_stream_receive,
+    .cleanup = net_stream_cleanup,
+};
+
+static void net_stream_listen(QIONetListener *listener,
+                              QIOChannelSocket *cioc,
+                              void *opaque)
+{
+    NetStreamState *s = opaque;
+    SocketAddress *addr;
+    char *uri;
+
+    object_ref(OBJECT(cioc));
+
+    qio_net_listener_set_client_func(s->listener, NULL, s, NULL);
+
+    s->ioc = QIO_CHANNEL(cioc);
+    qio_channel_set_name(s->ioc, "stream-server");
+    s->nc.link_down = false;
+
+    s->ioc_read_tag = qio_channel_add_watch(s->ioc, G_IO_IN, net_stream_send,
+                                            s, NULL);
+
+    if (cioc->localAddr.ss_family == AF_UNIX) {
+        addr = qio_channel_socket_get_local_address(cioc, NULL);
+    } else {
+        addr = qio_channel_socket_get_remote_address(cioc, NULL);
+    }
+    g_assert(addr != NULL);
+    uri = socket_uri(addr);
+    qemu_set_info_str(&s->nc, uri);
+    g_free(uri);
+    qapi_event_send_netdev_stream_connected(s->nc.name, addr);
+    qapi_free_SocketAddress(addr);
+}
+
+static void net_stream_server_listening(QIOTask *task, gpointer opaque)
+{
+    NetStreamState *s = opaque;
+    QIOChannelSocket *listen_sioc = QIO_CHANNEL_SOCKET(s->listen_ioc);
+    SocketAddress *addr;
+    int ret;
+
+    if (listen_sioc->fd < 0) {
+        qemu_set_info_str(&s->nc, "connection error");
+        return;
+    }
+
+    addr = qio_channel_socket_get_local_address(listen_sioc, NULL);
+    g_assert(addr != NULL);
+    ret = qemu_socket_try_set_nonblock(listen_sioc->fd);
+    if (addr->type == SOCKET_ADDRESS_TYPE_FD && ret < 0) {
+        qemu_set_info_str(&s->nc, "can't use file descriptor %s (errno %d)",
+                          addr->u.fd.str, -ret);
+        return;
+    }
+    g_assert(ret == 0);
+    qapi_free_SocketAddress(addr);
+
+    s->nc.link_down = true;
+    s->listener = qio_net_listener_new();
+
+    net_socket_rs_init(&s->rs, net_stream_rs_finalize, false);
+    qio_net_listener_set_client_func(s->listener, net_stream_listen, s, NULL);
+    qio_net_listener_add(s->listener, listen_sioc);
+}
+
+static int net_stream_server_init(NetClientState *peer,
+                                  const char *model,
+                                  const char *name,
+                                  SocketAddress *addr,
+                                  Error **errp)
+{
+    NetClientState *nc;
+    NetStreamState *s;
+    QIOChannelSocket *listen_sioc = qio_channel_socket_new();
+
+    nc = qemu_new_net_client(&net_stream_info, peer, model, name);
+    s = DO_UPCAST(NetStreamState, nc, nc);
+
+    s->listen_ioc = QIO_CHANNEL(listen_sioc);
+    qio_channel_socket_listen_async(listen_sioc, addr, 0,
+                                    net_stream_server_listening, s,
+                                    NULL, NULL);
+
+    return 0;
+}
+
+static void net_stream_client_connected(QIOTask *task, gpointer opaque)
+{
+    NetStreamState *s = opaque;
+    QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(s->ioc);
+    SocketAddress *addr;
+    gchar *uri;
+    int ret;
+
+    if (sioc->fd < 0) {
+        qemu_set_info_str(&s->nc, "connection error");
+        goto error;
+    }
+
+    addr = qio_channel_socket_get_remote_address(sioc, NULL);
+    g_assert(addr != NULL);
+    uri = socket_uri(addr);
+    qemu_set_info_str(&s->nc, uri);
+    g_free(uri);
+
+    ret = qemu_socket_try_set_nonblock(sioc->fd);
+    if (addr->type == SOCKET_ADDRESS_TYPE_FD && ret < 0) {
+        qemu_set_info_str(&s->nc, "can't use file descriptor %s (errno %d)",
+                          addr->u.fd.str, -ret);
+        qapi_free_SocketAddress(addr);
+        goto error;
+    }
+    g_assert(ret == 0);
+
+    net_socket_rs_init(&s->rs, net_stream_rs_finalize, false);
+
+    /* Disable Nagle algorithm on TCP sockets to reduce latency */
+    qio_channel_set_delay(s->ioc, false);
+
+    s->ioc_read_tag = qio_channel_add_watch(s->ioc, G_IO_IN, net_stream_send,
+                                            s, NULL);
+    s->nc.link_down = false;
+    qapi_event_send_netdev_stream_connected(s->nc.name, addr);
+    qapi_free_SocketAddress(addr);
+
+    return;
+error:
+    object_unref(OBJECT(s->ioc));
+    s->ioc = NULL;
+}
+
+static int net_stream_client_init(NetClientState *peer,
+                                  const char *model,
+                                  const char *name,
+                                  SocketAddress *addr,
+                                  Error **errp)
+{
+    NetStreamState *s;
+    NetClientState *nc;
+    QIOChannelSocket *sioc = qio_channel_socket_new();
+
+    nc = qemu_new_net_client(&net_stream_info, peer, model, name);
+    s = DO_UPCAST(NetStreamState, nc, nc);
+
+    s->ioc = QIO_CHANNEL(sioc);
+    s->nc.link_down = true;
+
+    qio_channel_socket_connect_async(sioc, addr,
+                                     net_stream_client_connected, s,
+                                     NULL, NULL);
+
+    return 0;
+}
+
+int net_init_stream(const Netdev *netdev, const char *name,
+                    NetClientState *peer, Error **errp)
+{
+    const NetdevStreamOptions *sock;
+
+    assert(netdev->type == NET_CLIENT_DRIVER_STREAM);
+    sock = &netdev->u.stream;
+
+    if (!sock->has_server || !sock->server) {
+        return net_stream_client_init(peer, "stream", name, sock->addr, errp);
+    }
+    return net_stream_server_init(peer, "stream", name, sock->addr, errp);
+}
diff --git a/net/tap-win32.c b/net/tap-win32.c
index 7466f22..a49c28b 100644
--- a/net/tap-win32.c
+++ b/net/tap-win32.c
@@ -789,8 +789,7 @@ static int tap_win32_init(NetClientState *peer, const char *model,
 
     s = DO_UPCAST(TAPState, nc, nc);
 
-    snprintf(s->nc.info_str, sizeof(s->nc.info_str),
-             "tap: ifname=%s", ifname);
+    qemu_set_info_str(&s->nc, "tap: ifname=%s", ifname);
 
     s->handle = handle;
 
diff --git a/net/tap.c b/net/tap.c
index e203d07..1210a04 100644
--- a/net/tap.c
+++ b/net/tap.c
@@ -630,8 +630,7 @@ int net_init_bridge(const Netdev *netdev, const char *name,
     }
     s = net_tap_fd_init(peer, "bridge", name, fd, vnet_hdr);
 
-    snprintf(s->nc.info_str, sizeof(s->nc.info_str), "helper=%s,br=%s", helper,
-             br);
+    qemu_set_info_str(&s->nc, "helper=%s,br=%s", helper, br);
 
     return 0;
 }
@@ -690,14 +689,12 @@ static void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer,
     }
 
     if (tap->has_fd || tap->has_fds) {
-        snprintf(s->nc.info_str, sizeof(s->nc.info_str), "fd=%d", fd);
+        qemu_set_info_str(&s->nc, "fd=%d", fd);
     } else if (tap->has_helper) {
-        snprintf(s->nc.info_str, sizeof(s->nc.info_str), "helper=%s",
-                 tap->helper);
+        qemu_set_info_str(&s->nc, "helper=%s", tap->helper);
     } else {
-        snprintf(s->nc.info_str, sizeof(s->nc.info_str),
-                 "ifname=%s,script=%s,downscript=%s", ifname, script,
-                 downscript);
+        qemu_set_info_str(&s->nc, "ifname=%s,script=%s,downscript=%s", ifname,
+                          script, downscript);
 
         if (strcmp(downscript, "no") != 0) {
             snprintf(s->down_script, sizeof(s->down_script), "%s", downscript);
diff --git a/net/vde.c b/net/vde.c
index 1083916..c0a0866 100644
--- a/net/vde.c
+++ b/net/vde.c
@@ -98,8 +98,7 @@ static int net_vde_init(NetClientState *peer, const char *model,
 
     nc = qemu_new_net_client(&net_vde_info, peer, model, name);
 
-    snprintf(nc->info_str, sizeof(nc->info_str), "sock=%s,fd=%d",
-             sock, vde_datafd(vde));
+    qemu_set_info_str(nc, "sock=%s,fd=%d", sock, vde_datafd(vde));
 
     s = DO_UPCAST(VDEState, nc, nc);
 
diff --git a/net/vhost-user.c b/net/vhost-user.c
index b1a0247..3a6b90d 100644
--- a/net/vhost-user.c
+++ b/net/vhost-user.c
@@ -341,8 +341,7 @@ static int net_vhost_user_init(NetClientState *peer, const char *device,
     user = g_new0(struct VhostUserState, 1);
     for (i = 0; i < queues; i++) {
         nc = qemu_new_net_client(&net_vhost_user_info, peer, device, name);
-        snprintf(nc->info_str, sizeof(nc->info_str), "vhost-user%d to %s",
-                 i, chr->label);
+        qemu_set_info_str(nc, "vhost-user%d to %s", i, chr->label);
         nc->queue_index = i;
         if (!nc0) {
             nc0 = nc;
diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c
index 4bc3fd0..854ebd61 100644
--- a/net/vhost-vdpa.c
+++ b/net/vhost-vdpa.c
@@ -63,7 +63,6 @@ const int vdpa_feature_bits[] = {
     VIRTIO_NET_F_CTRL_RX,
     VIRTIO_NET_F_CTRL_RX_EXTRA,
     VIRTIO_NET_F_CTRL_VLAN,
-    VIRTIO_NET_F_GUEST_ANNOUNCE,
     VIRTIO_NET_F_CTRL_MAC_ADDR,
     VIRTIO_NET_F_RSS,
     VIRTIO_NET_F_MQ,
@@ -463,48 +462,6 @@ static NetClientInfo net_vhost_vdpa_cvq_info = {
 };
 
 /**
- * Do not forward commands not supported by SVQ. Otherwise, the device could
- * accept it and qemu would not know how to update the device model.
- */
-static bool vhost_vdpa_net_cvq_validate_cmd(const void *out_buf, size_t len)
-{
-    struct virtio_net_ctrl_hdr ctrl;
-
-    if (unlikely(len < sizeof(ctrl))) {
-        qemu_log_mask(LOG_GUEST_ERROR,
-                      "%s: invalid legnth of out buffer %zu\n", __func__, len);
-        return false;
-    }
-
-    memcpy(&ctrl, out_buf, sizeof(ctrl));
-    switch (ctrl.class) {
-    case VIRTIO_NET_CTRL_MAC:
-        switch (ctrl.cmd) {
-        case VIRTIO_NET_CTRL_MAC_ADDR_SET:
-            return true;
-        default:
-            qemu_log_mask(LOG_GUEST_ERROR, "%s: invalid mac cmd %u\n",
-                          __func__, ctrl.cmd);
-        };
-        break;
-    case VIRTIO_NET_CTRL_MQ:
-        switch (ctrl.cmd) {
-        case VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET:
-            return true;
-        default:
-            qemu_log_mask(LOG_GUEST_ERROR, "%s: invalid mq cmd %u\n",
-                          __func__, ctrl.cmd);
-        };
-        break;
-    default:
-        qemu_log_mask(LOG_GUEST_ERROR, "%s: invalid control class %u\n",
-                      __func__, ctrl.class);
-    };
-
-    return false;
-}
-
-/**
  * Validate and copy control virtqueue commands.
  *
  * Following QEMU guidelines, we offer a copy of the buffers to the device to
@@ -527,16 +484,10 @@ static int vhost_vdpa_net_handle_ctrl_avail(VhostShadowVirtqueue *svq,
         .iov_len = sizeof(status),
     };
     ssize_t dev_written = -EINVAL;
-    bool ok;
 
     out.iov_len = iov_to_buf(elem->out_sg, elem->out_num, 0,
                              s->cvq_cmd_out_buffer,
                              vhost_vdpa_net_cvq_cmd_len());
-    ok = vhost_vdpa_net_cvq_validate_cmd(s->cvq_cmd_out_buffer, out.iov_len);
-    if (unlikely(!ok)) {
-        goto out;
-    }
-
     dev_written = vhost_vdpa_net_cvq_add(s, out.iov_len, sizeof(status));
     if (unlikely(dev_written < 0)) {
         goto out;
@@ -593,7 +544,7 @@ static NetClientState *net_vhost_vdpa_init(NetClientState *peer,
         nc = qemu_new_net_control_client(&net_vhost_vdpa_cvq_info, peer,
                                          device, name);
     }
-    snprintf(nc->info_str, sizeof(nc->info_str), TYPE_VHOST_VDPA);
+    qemu_set_info_str(nc, TYPE_VHOST_VDPA);
     s = DO_UPCAST(VhostVDPAState, nc, nc);
 
     s->vhost_vdpa.device_fd = vdpa_device_fd;
@@ -683,14 +634,29 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name,
 
     assert(netdev->type == NET_CLIENT_DRIVER_VHOST_VDPA);
     opts = &netdev->u.vhost_vdpa;
-    if (!opts->vhostdev) {
-        error_setg(errp, "vdpa character device not specified with vhostdev");
+    if (!opts->has_vhostdev && !opts->has_vhostfd) {
+        error_setg(errp,
+                   "vhost-vdpa: neither vhostdev= nor vhostfd= was specified");
         return -1;
     }
 
-    vdpa_device_fd = qemu_open(opts->vhostdev, O_RDWR, errp);
-    if (vdpa_device_fd == -1) {
-        return -errno;
+    if (opts->has_vhostdev && opts->has_vhostfd) {
+        error_setg(errp,
+                   "vhost-vdpa: vhostdev= and vhostfd= are mutually exclusive");
+        return -1;
+    }
+
+    if (opts->has_vhostdev) {
+        vdpa_device_fd = qemu_open(opts->vhostdev, O_RDWR, errp);
+        if (vdpa_device_fd == -1) {
+            return -errno;
+        }
+    } else if (opts->has_vhostfd) {
+        vdpa_device_fd = monitor_fd_param(monitor_cur(), opts->vhostfd, errp);
+        if (vdpa_device_fd == -1) {
+            error_prepend(errp, "vhost-vdpa: unable to parse vhostfd: ");
+            return -1;
+        }
     }
 
     r = vhost_vdpa_get_features(vdpa_device_fd, &features, errp);
diff --git a/qapi/net.json b/qapi/net.json
index dd088c0..522ac58 100644
--- a/qapi/net.json
+++ b/qapi/net.json
@@ -7,6 +7,7 @@
 ##
 
 { 'include': 'common.json' }
+{ 'include': 'sockets.json' }
 
 ##
 # @set_link:
@@ -442,6 +443,8 @@
 # @vhostdev: path of vhost-vdpa device
 #            (default:'/dev/vhost-vdpa-0')
 #
+# @vhostfd: file descriptor of an already opened vhost vdpa device
+#
 # @queues: number of queues to be created for multiqueue vhost-vdpa
 #          (default: 1)
 #
@@ -456,6 +459,7 @@
 { 'struct': 'NetdevVhostVDPAOptions',
   'data': {
     '*vhostdev':     'str',
+    '*vhostfd':      'str',
     '*queues':       'int',
     '*x-svq':        {'type': 'bool', 'features' : [ 'unstable'] } } }
 
@@ -574,6 +578,60 @@
   'if': 'CONFIG_VMNET' }
 
 ##
+# @NetdevStreamOptions:
+#
+# Configuration info for stream socket netdev
+#
+# @addr: socket address to listen on (server=true)
+#        or connect to (server=false)
+# @server: create server socket (default: false)
+#
+# Only SocketAddress types 'unix', 'inet' and 'fd' are supported.
+#
+# Since: 7.2
+##
+{ 'struct': 'NetdevStreamOptions',
+  'data': {
+    'addr':   'SocketAddress',
+    '*server': 'bool' } }
+
+##
+# @NetdevDgramOptions:
+#
+# Configuration info for datagram socket netdev.
+#
+# @remote: remote address
+# @local: local address
+#
+# Only SocketAddress types 'unix', 'inet' and 'fd' are supported.
+#
+# If remote address is present and it's a multicast address, local address
+# is optional. Otherwise local address is required and remote address is
+# optional.
+#
+# .. table:: Valid parameters combination table
+#    :widths: auto
+#
+#    =============  ========  =====
+#    remote         local     okay?
+#    =============  ========  =====
+#    absent         absent    no
+#    absent         not fd    no
+#    absent         fd        yes
+#    multicast      absent    yes
+#    multicast      present   yes
+#    not multicast  absent    no
+#    not multicast  present   yes
+#    =============  ========  =====
+#
+# Since: 7.2
+##
+{ 'struct': 'NetdevDgramOptions',
+  'data': {
+    '*local':  'SocketAddress',
+    '*remote': 'SocketAddress' } }
+
+##
 # @NetClientDriver:
 #
 # Available netdev drivers.
@@ -584,10 +642,13 @@
 #        @vmnet-host since 7.1
 #        @vmnet-shared since 7.1
 #        @vmnet-bridged since 7.1
+#        @stream since 7.2
+#        @dgram since 7.2
 ##
 { 'enum': 'NetClientDriver',
-  'data': [ 'none', 'nic', 'user', 'tap', 'l2tpv3', 'socket', 'vde',
-            'bridge', 'hubport', 'netmap', 'vhost-user', 'vhost-vdpa',
+  'data': [ 'none', 'nic', 'user', 'tap', 'l2tpv3', 'socket', 'stream',
+            'dgram', 'vde', 'bridge', 'hubport', 'netmap', 'vhost-user',
+            'vhost-vdpa',
             { 'name': 'vmnet-host', 'if': 'CONFIG_VMNET' },
             { 'name': 'vmnet-shared', 'if': 'CONFIG_VMNET' },
             { 'name': 'vmnet-bridged', 'if': 'CONFIG_VMNET' }] }
@@ -607,6 +668,8 @@
 #        'vmnet-host' - since 7.1
 #        'vmnet-shared' - since 7.1
 #        'vmnet-bridged' - since 7.1
+#        'stream' since 7.2
+#        'dgram' since 7.2
 ##
 { 'union': 'Netdev',
   'base': { 'id': 'str', 'type': 'NetClientDriver' },
@@ -617,6 +680,8 @@
     'tap':      'NetdevTapOptions',
     'l2tpv3':   'NetdevL2TPv3Options',
     'socket':   'NetdevSocketOptions',
+    'stream':   'NetdevStreamOptions',
+    'dgram':    'NetdevDgramOptions',
     'vde':      'NetdevVdeOptions',
     'bridge':   'NetdevBridgeOptions',
     'hubport':  'NetdevHubPortOptions',
@@ -833,3 +898,52 @@
 ##
 { 'event': 'FAILOVER_NEGOTIATED',
   'data': {'device-id': 'str'} }
+
+##
+# @NETDEV_STREAM_CONNECTED:
+#
+# Emitted when the netdev stream backend is connected
+#
+# @netdev-id: QEMU netdev id that is connected
+# @addr: The destination address
+#
+# Since: 7.2
+#
+# Example:
+#
+# <- { "event": "NETDEV_STREAM_CONNECTED",
+#      "data": { "netdev-id": "netdev0",
+#                "addr": { "port": "47666", "ipv6": true,
+#                          "host": "::1", "type": "inet" } },
+#      "timestamp": { "seconds": 1666269863, "microseconds": 311222 } }
+#
+# or
+#
+# <- { "event": "NETDEV_STREAM_CONNECTED",
+#      "data": { "netdev-id": "netdev0",
+#                "addr": { "path": "/tmp/qemu0", "type": "unix" } },
+#      "timestamp": { "seconds": 1666269706, "microseconds": 413651 } }
+#
+##
+{ 'event': 'NETDEV_STREAM_CONNECTED',
+  'data': { 'netdev-id': 'str',
+            'addr': 'SocketAddress' } }
+
+##
+# @NETDEV_STREAM_DISCONNECTED:
+#
+# Emitted when the netdev stream backend is disconnected
+#
+# @netdev-id: QEMU netdev id that is disconnected
+#
+# Since: 7.2
+#
+# Example:
+#
+# <- { 'event': 'NETDEV_STREAM_DISCONNECTED',
+#      'data': {'netdev-id': 'netdev0'},
+#      'timestamp': {'seconds': 1663330937, 'microseconds': 526695} }
+#
+##
+{ 'event': 'NETDEV_STREAM_DISCONNECTED',
+  'data': { 'netdev-id': 'str' } }
diff --git a/qemu-options.hx b/qemu-options.hx
index eb38e5d..ceee0dd 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -2772,6 +2772,20 @@ DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
     "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n"
     "                configure a network backend to connect to another network\n"
     "                using an UDP tunnel\n"
+    "-netdev stream,id=str[,server=on|off],addr.type=inet,addr.host=host,addr.port=port[,to=maxport][,numeric=on|off][,keep-alive=on|off][,mptcp=on|off][,addr.ipv4=on|off][,addr.ipv6=on|off]\n"
+    "-netdev stream,id=str[,server=on|off],addr.type=unix,addr.path=path[,abstract=on|off][,tight=on|off]\n"
+    "-netdev stream,id=str[,server=on|off],addr.type=fd,addr.str=file-descriptor\n"
+    "                configure a network backend to connect to another network\n"
+    "                using a socket connection in stream mode.\n"
+    "-netdev dgram,id=str,remote.type=inet,remote.host=maddr,remote.port=port[,local.type=inet,local.host=addr]\n"
+    "-netdev dgram,id=str,remote.type=inet,remote.host=maddr,remote.port=port[,local.type=fd,local.str=file-descriptor]\n"
+    "                configure a network backend to connect to a multicast maddr and port\n"
+    "                use ``local.host=addr`` to specify the host address to send packets from\n"
+    "-netdev dgram,id=str,local.type=inet,local.host=addr,local.port=port[,remote.type=inet,remote.host=addr,remote.port=port]\n"
+    "-netdev dgram,id=str,local.type=unix,local.path=path[,remote.type=unix,remote.path=path]\n"
+    "-netdev dgram,id=str,local.type=fd,local.str=file-descriptor\n"
+    "                configure a network backend to connect to another network\n"
+    "                using an UDP tunnel\n"
 #ifdef CONFIG_VDE
     "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
     "                configure a network backend to connect to port 'n' of a vde switch\n"
@@ -2790,8 +2804,10 @@ DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
     "                configure a vhost-user network, backed by a chardev 'dev'\n"
 #endif
 #ifdef __linux__
-    "-netdev vhost-vdpa,id=str,vhostdev=/path/to/dev\n"
+    "-netdev vhost-vdpa,id=str[,vhostdev=/path/to/dev][,vhostfd=h]\n"
     "                configure a vhost-vdpa network,Establish a vhost-vdpa netdev\n"
+    "                use 'vhostdev=/path/to/dev' to open a vhost vdpa device\n"
+    "                use 'vhostfd=h' to connect to an already opened vhost vdpa device\n"
 #endif
 #ifdef CONFIG_VMNET
     "-netdev vmnet-host,id=str[,isolated=on|off][,net-uuid=uuid]\n"
@@ -3296,7 +3312,7 @@ SRST
              -netdev type=vhost-user,id=net0,chardev=chr0 \
              -device virtio-net-pci,netdev=net0
 
-``-netdev vhost-vdpa,vhostdev=/path/to/dev``
+``-netdev vhost-vdpa[,vhostdev=/path/to/dev][,vhostfd=h]``
     Establish a vhost-vdpa netdev.
 
     vDPA device is a device that uses a datapath which complies with
diff --git a/softmmu/vl.c b/softmmu/vl.c
index b464da2..99fb49c 100644
--- a/softmmu/vl.c
+++ b/softmmu/vl.c
@@ -1904,7 +1904,7 @@ static void qemu_create_late_backends(void)
         qtest_server_init(qtest_chrdev, qtest_log, &error_fatal);
     }
 
-    net_init_clients(&error_fatal);
+    net_init_clients();
 
     object_option_foreach_add(object_create_late);
 
@@ -2801,21 +2801,19 @@ void qemu_init(int argc, char **argv)
                 break;
             case QEMU_OPTION_netdev:
                 default_net = 0;
-                if (net_client_parse(qemu_find_opts("netdev"), optarg) == -1) {
-                    exit(1);
+                if (netdev_is_modern(optarg)) {
+                    netdev_parse_modern(optarg);
+                } else {
+                    net_client_parse(qemu_find_opts("netdev"), optarg);
                 }
                 break;
             case QEMU_OPTION_nic:
                 default_net = 0;
-                if (net_client_parse(qemu_find_opts("nic"), optarg) == -1) {
-                    exit(1);
-                }
+                net_client_parse(qemu_find_opts("nic"), optarg);
                 break;
             case QEMU_OPTION_net:
                 default_net = 0;
-                if (net_client_parse(qemu_find_opts("net"), optarg) == -1) {
-                    exit(1);
-                }
+                net_client_parse(qemu_find_opts("net"), optarg);
                 break;
 #ifdef CONFIG_LIBISCSI
             case QEMU_OPTION_iscsi:
diff --git a/util/qemu-sockets.c b/util/qemu-sockets.c
index 0c41ca9..d185245 100644
--- a/util/qemu-sockets.c
+++ b/util/qemu-sockets.c
@@ -1076,6 +1076,26 @@ int unix_connect(const char *path, Error **errp)
     return sock;
 }
 
+char *socket_uri(SocketAddress *addr)
+{
+    switch (addr->type) {
+    case SOCKET_ADDRESS_TYPE_INET:
+        return g_strdup_printf("tcp:%s:%s",
+                               addr->u.inet.host,
+                               addr->u.inet.port);
+    case SOCKET_ADDRESS_TYPE_UNIX:
+        return g_strdup_printf("unix:%s",
+                               addr->u.q_unix.path);
+    case SOCKET_ADDRESS_TYPE_FD:
+        return g_strdup_printf("fd:%s", addr->u.fd.str);
+    case SOCKET_ADDRESS_TYPE_VSOCK:
+        return g_strdup_printf("vsock:%s:%s",
+                               addr->u.vsock.cid,
+                               addr->u.vsock.port);
+    default:
+        return g_strdup("unknown address type");
+    }
+}
 
 SocketAddress *socket_parse(const char *str, Error **errp)
 {
@@ -1103,6 +1123,11 @@ SocketAddress *socket_parse(const char *str, Error **errp)
         if (vsock_parse(&addr->u.vsock, str + strlen("vsock:"), errp)) {
             goto fail;
         }
+    } else if (strstart(str, "tcp:", NULL)) {
+        addr->type = SOCKET_ADDRESS_TYPE_INET;
+        if (inet_parse(&addr->u.inet, str + strlen("tcp:"), errp)) {
+            goto fail;
+        }
     } else {
         addr->type = SOCKET_ADDRESS_TYPE_INET;
         if (inet_parse(&addr->u.inet, str, errp)) {