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>

docs/system/devices/net.rst

@@ -85,13 +85,59 @@ passt doesn't require any capability or privilege. passt has
 better performance than ``-net user``, full IPv6 support and better security
 as it's a daemon that is not executed in QEMU context.
 
-passt can be connected to QEMU either by using a socket
-(``-netdev stream``) or using the vhost-user interface (``-netdev vhost-user``).
+passt_ can be used in the same way as the user backend (using ``-net passt``,
+``-netdev passt`` or ``-nic passt``) or it can be launched manually and
+connected to QEMU either by using a socket (``-netdev stream``) or by using
+the vhost-user interface (``-netdev vhost-user``).
+
+Using ``-netdev stream`` or ``-netdev vhost-user`` will allow the user to
+enable functionalities not available through the passt backend interface
+(like migration).
+
 See `passt(1)`_ for more details on passt.
 
 .. _passt: https://passt.top/
 .. _passt(1): https://passt.top/builds/latest/web/passt.1.html
 
+To use the passt backend interface
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+There is no need to start the daemon as QEMU will do it for you.
+
+By default, passt will be started in the socket-based mode.
+
+.. parsed-literal::
+   |qemu_system| [...OPTIONS...] -nic passt
+
+   (qemu) info network
+   e1000e.0: index=0,type=nic,model=e1000e,macaddr=52:54:00:12:34:56
+    \ #net071: index=0,type=passt,stream,connected to pid 24846
+
+.. parsed-literal::
+   |qemu_system| [...OPTIONS...] -net nic -net passt,tcp-ports=10001,udp-ports=10001
+
+   (qemu) info network
+   hub 0
+    \ hub0port1: #net136: index=0,type=passt,stream,connected to pid 25204
+    \ hub0port0: e1000e.0: index=0,type=nic,model=e1000e,macaddr=52:54:00:12:34:56
+
+.. parsed-literal::
+   |qemu_system| [...OPTIONS...] -netdev passt,id=netdev0 -device virtio-net,mac=9a:2b:2c:2d:2e:2f,id=virtio0,netdev=netdev0
+
+   (qemu) info network
+   virtio0: index=0,type=nic,model=virtio-net-pci,macaddr=9a:2b:2c:2d:2e:2f
+    \ netdev0: index=0,type=passt,stream,connected to pid 25428
+
+To use the vhost-based interface, add the ``vhost-user=on`` parameter and
+select the virtio-net device:
+
+.. parsed-literal::
+   |qemu_system| [...OPTIONS...] -nic passt,model=virtio,vhost-user=on
+
+   (qemu) info network
+   virtio-net-pci.0: index=0,type=nic,model=virtio-net-pci,macaddr=52:54:00:12:34:56
+    \ #net006: index=0,type=passt,vhost-user,connected to pid 25731
+
 To use socket based passt interface:
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 

hmp-commands.hx

@@ -1287,6 +1287,9 @@ ERST
         .name       = "netdev_add",
         .args_type  = "netdev:O",
         .params     = "[user|tap|socket|stream|dgram|vde|bridge|hubport|netmap|vhost-user"
+#ifdef CONFIG_PASST
+                      "|passt"
+#endif
 #ifdef CONFIG_AF_XDP
                       "|af-xdp"
 #endif

hw/net/vhost_net-stub.c

@@ -13,7 +13,6 @@
 #include "qemu/osdep.h"
 #include "net/net.h"
 #include "net/tap.h"
-#include "net/vhost-user.h"
 
 #include "hw/virtio/virtio-net.h"
 #include "net/vhost_net.h"
@@ -101,7 +100,7 @@ VHostNetState *get_vhost_net(NetClientState *nc)
     return 0;
 }
 
-int vhost_set_vring_enable(NetClientState *nc, int enable)
+int vhost_net_set_vring_enable(NetClientState *nc, int enable)
 {
     return 0;
 }

hw/net/vhost_net.c

@@ -16,7 +16,6 @@
 #include "qemu/osdep.h"
 #include "net/net.h"
 #include "net/tap.h"
-#include "net/vhost-user.h"
 #include "net/vhost-vdpa.h"
 
 #include "standard-headers/linux/vhost_types.h"
@@ -36,94 +35,9 @@
 #include "hw/virtio/virtio-bus.h"
 #include "linux-headers/linux/vhost.h"
 
-
-/* Features supported by host kernel. */
-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
-};
-
-/* Features supported by others. */
-static const int user_feature_bits[] = {
-    VIRTIO_F_NOTIFY_ON_EMPTY,
-    VIRTIO_F_NOTIFICATION_DATA,
-    VIRTIO_RING_F_INDIRECT_DESC,
-    VIRTIO_RING_F_EVENT_IDX,
-
-    VIRTIO_F_ANY_LAYOUT,
-    VIRTIO_F_VERSION_1,
-    VIRTIO_NET_F_CSUM,
-    VIRTIO_NET_F_GUEST_CSUM,
-    VIRTIO_NET_F_GSO,
-    VIRTIO_NET_F_GUEST_TSO4,
-    VIRTIO_NET_F_GUEST_TSO6,
-    VIRTIO_NET_F_GUEST_ECN,
-    VIRTIO_NET_F_GUEST_UFO,
-    VIRTIO_NET_F_HOST_TSO4,
-    VIRTIO_NET_F_HOST_TSO6,
-    VIRTIO_NET_F_HOST_ECN,
-    VIRTIO_NET_F_HOST_UFO,
-    VIRTIO_NET_F_MRG_RXBUF,
-    VIRTIO_NET_F_MTU,
-    VIRTIO_F_IOMMU_PLATFORM,
-    VIRTIO_F_RING_PACKED,
-    VIRTIO_F_RING_RESET,
-    VIRTIO_F_IN_ORDER,
-    VIRTIO_NET_F_RSS,
-    VIRTIO_NET_F_RSC_EXT,
-    VIRTIO_NET_F_HASH_REPORT,
-    VIRTIO_NET_F_GUEST_USO4,
-    VIRTIO_NET_F_GUEST_USO6,
-    VIRTIO_NET_F_HOST_USO,
-
-    /* This bit implies RARP isn't sent by QEMU out of band */
-    VIRTIO_NET_F_GUEST_ANNOUNCE,
-
-    VIRTIO_NET_F_MQ,
-
-    VHOST_INVALID_FEATURE_BIT
-};
-
-static const int *vhost_net_get_feature_bits(struct vhost_net *net)
-{
-    const int *feature_bits = 0;
-
-    switch (net->nc->info->type) {
-    case NET_CLIENT_DRIVER_TAP:
-        feature_bits = kernel_feature_bits;
-        break;
-    case NET_CLIENT_DRIVER_VHOST_USER:
-        feature_bits = user_feature_bits;
-        break;
-#ifdef CONFIG_VHOST_NET_VDPA
-    case NET_CLIENT_DRIVER_VHOST_VDPA:
-        feature_bits = vdpa_feature_bits;
-        break;
-#endif
-    default:
-        error_report("Feature bits not defined for this type: %d",
-                net->nc->info->type);
-        break;
-    }
-
-    return feature_bits;
-}
-
 uint64_t vhost_net_get_features(struct vhost_net *net, uint64_t features)
 {
-    return vhost_get_features(&net->dev, vhost_net_get_feature_bits(net),
+    return vhost_get_features(&net->dev, net->feature_bits,
             features);
 }
 int vhost_net_get_config(struct vhost_net *net,  uint8_t *config,
@@ -140,7 +54,7 @@ int vhost_net_set_config(struct vhost_net *net, const uint8_t *data,
 void vhost_net_ack_features(struct vhost_net *net, uint64_t features)
 {
     net->dev.acked_features = net->dev.backend_features;
-    vhost_ack_features(&net->dev, vhost_net_get_feature_bits(net), features);
+    vhost_ack_features(&net->dev, net->feature_bits, features);
 }
 
 uint64_t vhost_net_get_max_queues(VHostNetState *net)
@@ -155,11 +69,11 @@ uint64_t vhost_net_get_acked_features(VHostNetState *net)
 
 void vhost_net_save_acked_features(NetClientState *nc)
 {
-#ifdef CONFIG_VHOST_NET_USER
-    if (nc->info->type == NET_CLIENT_DRIVER_VHOST_USER) {
-        vhost_user_save_acked_features(nc);
+    struct vhost_net *net = get_vhost_net(nc);
+
+    if (net && net->save_acked_features) {
+        net->save_acked_features(nc);
     }
-#endif
 }
 
 static void vhost_net_disable_notifiers_nvhosts(VirtIODevice *dev,
@@ -329,6 +243,10 @@ struct vhost_net *vhost_net_init(VhostNetOptions *options)
     }
     net->nc = options->net_backend;
     net->dev.nvqs = options->nvqs;
+    net->feature_bits = options->feature_bits;
+    net->save_acked_features = options->save_acked_features;
+    net->max_tx_queue_size = options->max_tx_queue_size;
+    net->is_vhost_user = options->is_vhost_user;
 
     net->dev.max_queues = 1;
     net->dev.vqs = net->vqs;
@@ -372,9 +290,8 @@ struct vhost_net *vhost_net_init(VhostNetOptions *options)
     }
 
     /* Set sane init value. Override when guest acks. */
-#ifdef CONFIG_VHOST_NET_USER
-    if (net->nc->info->type == NET_CLIENT_DRIVER_VHOST_USER) {
-        features = vhost_user_get_acked_features(net->nc);
+    if (options->get_acked_features) {
+        features = options->get_acked_features(net->nc);
         if (~net->dev.features & features) {
             fprintf(stderr, "vhost lacks feature mask 0x%" PRIx64
                     " for backend\n",
@@ -382,7 +299,6 @@ struct vhost_net *vhost_net_init(VhostNetOptions *options)
             goto fail;
         }
     }
-#endif
 
     vhost_net_ack_features(net, features);
 
@@ -525,7 +441,7 @@ int vhost_net_start(VirtIODevice *dev, NetClientState *ncs,
          * because vhost user doesn't interrupt masking/unmasking
          * properly.
          */
-        if (net->nc->info->type == NET_CLIENT_DRIVER_VHOST_USER) {
+        if (net->is_vhost_user) {
             dev->use_guest_notifier_mask = false;
         }
      }
@@ -551,7 +467,7 @@ int vhost_net_start(VirtIODevice *dev, NetClientState *ncs,
 
         if (peer->vring_enable) {
             /* restore vring enable state */
-            r = vhost_set_vring_enable(peer, peer->vring_enable);
+            r = vhost_net_set_vring_enable(peer, peer->vring_enable);
 
             if (r < 0) {
                 goto err_guest_notifiers;
@@ -649,44 +565,21 @@ void vhost_net_config_mask(VHostNetState *net, VirtIODevice *dev, bool mask)
 {
     vhost_config_mask(&net->dev, dev, mask);
 }
+
 VHostNetState *get_vhost_net(NetClientState *nc)
 {
-    VHostNetState *vhost_net = 0;
-
     if (!nc) {
         return 0;
     }
 
-    switch (nc->info->type) {
-    case NET_CLIENT_DRIVER_TAP:
-        vhost_net = tap_get_vhost_net(nc);
-        /*
-         * 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().
-         * Hence, we omit the assertion here.
-         */
-        break;
-#ifdef CONFIG_VHOST_NET_USER
-    case NET_CLIENT_DRIVER_VHOST_USER:
-        vhost_net = vhost_user_get_vhost_net(nc);
-        assert(vhost_net);
-        break;
-#endif
-#ifdef CONFIG_VHOST_NET_VDPA
-    case NET_CLIENT_DRIVER_VHOST_VDPA:
-        vhost_net = vhost_vdpa_get_vhost_net(nc);
-        assert(vhost_net);
-        break;
-#endif
-    default:
-        break;
+    if (nc->info->get_vhost_net) {
+        return nc->info->get_vhost_net(nc);
     }
 
-    return vhost_net;
+    return NULL;
 }
 
-int vhost_set_vring_enable(NetClientState *nc, int enable)
+int vhost_net_set_vring_enable(NetClientState *nc, int enable)
 {
     VHostNetState *net = get_vhost_net(nc);
     const VhostOps *vhost_ops = net->dev.vhost_ops;

hw/net/virtio-net.c

@@ -670,34 +670,36 @@ static void virtio_net_set_mrg_rx_bufs(VirtIONet *n, int mergeable_rx_bufs,
 static int virtio_net_max_tx_queue_size(VirtIONet *n)
 {
     NetClientState *peer = n->nic_conf.peers.ncs[0];
+    struct vhost_net *net;
 
-    /*
-     * Backends other than vhost-user or vhost-vdpa don't support max queue
-     * size.
-     */
     if (!peer) {
-        return VIRTIO_NET_TX_QUEUE_DEFAULT_SIZE;
+        goto default_value;
     }
 
-    switch(peer->info->type) {
-    case NET_CLIENT_DRIVER_VHOST_USER:
-    case NET_CLIENT_DRIVER_VHOST_VDPA:
-        return VIRTQUEUE_MAX_SIZE;
-    default:
-        return VIRTIO_NET_TX_QUEUE_DEFAULT_SIZE;
-    };
+    net = get_vhost_net(peer);
+
+    if (!net || !net->max_tx_queue_size) {
+        goto default_value;
+    }
+
+    return net->max_tx_queue_size;
+
+default_value:
+    return VIRTIO_NET_TX_QUEUE_DEFAULT_SIZE;
 }
 
 static int peer_attach(VirtIONet *n, int index)
 {
     NetClientState *nc = qemu_get_subqueue(n->nic, index);
+    struct vhost_net *net;
 
     if (!nc->peer) {
         return 0;
     }
 
-    if (nc->peer->info->type == NET_CLIENT_DRIVER_VHOST_USER) {
-        vhost_set_vring_enable(nc->peer, 1);
+    net = get_vhost_net(nc->peer);
+    if (net && net->is_vhost_user) {
+        vhost_net_set_vring_enable(nc->peer, 1);
     }
 
     if (nc->peer->info->type != NET_CLIENT_DRIVER_TAP) {
@@ -714,13 +716,15 @@ static int peer_attach(VirtIONet *n, int index)
 static int peer_detach(VirtIONet *n, int index)
 {
     NetClientState *nc = qemu_get_subqueue(n->nic, index);
+    struct vhost_net *net;
 
     if (!nc->peer) {
         return 0;
     }
 
-    if (nc->peer->info->type == NET_CLIENT_DRIVER_VHOST_USER) {
-        vhost_set_vring_enable(nc->peer, 0);
+    net = get_vhost_net(nc->peer);
+    if (net && net->is_vhost_user) {
+        vhost_net_set_vring_enable(nc->peer, 0);
     }
 
     if (nc->peer->info->type !=  NET_CLIENT_DRIVER_TAP) {
@@ -3022,11 +3026,10 @@ static void virtio_net_del_queue(VirtIONet *n, int index)
     virtio_del_queue(vdev, index * 2 + 1);
 }
 
-static void virtio_net_change_num_queue_pairs(VirtIONet *n, int new_max_queue_pairs)
+static void virtio_net_change_num_queues(VirtIONet *n, int new_num_queues)
 {
     VirtIODevice *vdev = VIRTIO_DEVICE(n);
     int old_num_queues = virtio_get_num_queues(vdev);
-    int new_num_queues = new_max_queue_pairs * 2 + 1;
     int i;
 
     assert(old_num_queues >= 3);
@@ -3062,16 +3065,14 @@ static void virtio_net_set_multiqueue(VirtIONet *n, int multiqueue)
     int max = multiqueue ? n->max_queue_pairs : 1;
 
     n->multiqueue = multiqueue;
-    virtio_net_change_num_queue_pairs(n, max);
+    virtio_net_change_num_queues(n, max * 2 + 1);
 
     virtio_net_set_queue_pairs(n);
 }
 
-static int virtio_net_pre_load_queues(VirtIODevice *vdev)
+static int virtio_net_pre_load_queues(VirtIODevice *vdev, uint32_t n)
 {
-    virtio_net_set_multiqueue(VIRTIO_NET(vdev),
-                              virtio_has_feature(vdev->guest_features, VIRTIO_NET_F_RSS) ||
-                              virtio_has_feature(vdev->guest_features, VIRTIO_NET_F_MQ));
+    virtio_net_change_num_queues(VIRTIO_NET(vdev), n);
 
     return 0;
 }

hw/virtio/virtio.c

@@ -3270,13 +3270,6 @@ virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id)
         config_len--;
     }
 
-    if (vdc->pre_load_queues) {
-        ret = vdc->pre_load_queues(vdev);
-        if (ret) {
-            return ret;
-        }
-    }
-
     num = qemu_get_be32(f);
 
     if (num > VIRTIO_QUEUE_MAX) {
@@ -3284,6 +3277,13 @@ virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id)
         return -1;
     }
 
+    if (vdc->pre_load_queues) {
+        ret = vdc->pre_load_queues(vdev, num);
+        if (ret) {
+            return ret;
+        }
+    }
+
     for (i = 0; i < num; i++) {
         vdev->vq[i].vring.num = qemu_get_be32(f);
         if (k->has_variable_vring_alignment) {

include/hw/virtio/vhost.h

@@ -1,6 +1,7 @@
 #ifndef VHOST_H
 #define VHOST_H
 
+#include "net/vhost_net.h"
 #include "hw/virtio/vhost-backend.h"
 #include "hw/virtio/virtio.h"
 #include "system/memory.h"
@@ -143,6 +144,10 @@ struct vhost_net {
     struct vhost_dev dev;
     struct vhost_virtqueue vqs[2];
     int backend;
+    const int *feature_bits;
+    int max_tx_queue_size;
+    SaveAcketFeatures *save_acked_features;
+    bool is_vhost_user;
     NetClientState *nc;
 };
 

include/hw/virtio/virtio.h

@@ -210,8 +210,14 @@ struct VirtioDeviceClass {
     void (*guest_notifier_mask)(VirtIODevice *vdev, int n, bool mask);
     int (*start_ioeventfd)(VirtIODevice *vdev);
     void (*stop_ioeventfd)(VirtIODevice *vdev);
-    /* Called before loading queues. Useful to add queues before loading. */
-    int (*pre_load_queues)(VirtIODevice *vdev);
+    /*
+     * Called before loading queues.
+     * If the number of queues change at runtime, use @n to know the
+     * number and add or remove queues accordingly.
+     * Note that this function is called in the middle of loading vmsd;
+     * no assumption should be made on states being loaded from vmsd.
+     */
+    int (*pre_load_queues)(VirtIODevice *vdev, uint32_t n);
     /* Saving and loading of a device; trying to deprecate save/load
      * use vmsd for new devices.
      */

include/net/net.h

@@ -67,6 +67,7 @@ typedef void (SocketReadStateFinalize)(SocketReadState *rs);
 typedef void (NetAnnounce)(NetClientState *);
 typedef bool (SetSteeringEBPF)(NetClientState *, int);
 typedef bool (NetCheckPeerType)(NetClientState *, ObjectClass *, Error **);
+typedef struct vhost_net *(GetVHostNet)(NetClientState *nc);
 
 typedef struct NetClientInfo {
     NetClientDriver type;
@@ -92,6 +93,7 @@ typedef struct NetClientInfo {
     NetAnnounce *announce;
     SetSteeringEBPF *set_steering_ebpf;
     NetCheckPeerType *check_peer_type;
+    GetVHostNet *get_vhost_net;
 } NetClientInfo;
 
 struct NetClientState {
@@ -298,6 +300,7 @@ void net_client_parse(QemuOptsList *opts_list, const char *optstr);
 void show_netdevs(void);
 void net_init_clients(void);
 void net_check_clients(void);
+void net_client_set_link(NetClientState **ncs, int queues, bool up);
 void net_cleanup(void);
 void hmp_host_net_add(Monitor *mon, const QDict *qdict);
 void hmp_host_net_remove(Monitor *mon, const QDict *qdict);

include/net/tap.h

@@ -33,7 +33,4 @@ int tap_disable(NetClientState *nc);
 
 int tap_get_fd(NetClientState *nc);
 
-struct vhost_net;
-struct vhost_net *tap_get_vhost_net(NetClientState *nc);
-
 #endif /* QEMU_NET_TAP_H */

include/net/vhost-user.h

@@ -1,19 +0,0 @@
-/*
- * vhost-user.h
- *
- * Copyright (c) 2013 Virtual Open Systems Sarl.
- *
- * This work is licensed under the terms of the GNU GPL, version 2 or later.
- * See the COPYING file in the top-level directory.
- *
- */
-
-#ifndef VHOST_USER_H
-#define VHOST_USER_H
-
-struct vhost_net;
-struct vhost_net *vhost_user_get_vhost_net(NetClientState *nc);
-uint64_t vhost_user_get_acked_features(NetClientState *nc);
-void vhost_user_save_acked_features(NetClientState *nc);
-
-#endif /* VHOST_USER_H */

include/net/vhost-vdpa.h

@@ -14,8 +14,4 @@
 
 #define TYPE_VHOST_VDPA "vhost-vdpa"
 
-struct vhost_net *vhost_vdpa_get_vhost_net(NetClientState *nc);
-
-extern const int vdpa_feature_bits[];
-
 #endif /* VHOST_VDPA_H */

include/net/vhost_net.h

@@ -7,11 +7,19 @@
 struct vhost_net;
 typedef struct vhost_net VHostNetState;
 
+typedef uint64_t (GetAckedFeatures)(NetClientState *nc);
+typedef void (SaveAcketFeatures)(NetClientState *nc);
+
 typedef struct VhostNetOptions {
     VhostBackendType backend_type;
     NetClientState *net_backend;
     uint32_t busyloop_timeout;
     unsigned int nvqs;
+    const int *feature_bits;
+    int max_tx_queue_size;
+    bool is_vhost_user;
+    GetAckedFeatures *get_acked_features;
+    SaveAcketFeatures *save_acked_features;
     void *opaque;
 } VhostNetOptions;
 
@@ -41,7 +49,7 @@ void vhost_net_config_mask(VHostNetState *net, VirtIODevice *dev, bool mask);
 int vhost_net_notify_migration_done(VHostNetState *net, char* mac_addr);
 VHostNetState *get_vhost_net(NetClientState *nc);
 
-int vhost_set_vring_enable(NetClientState * nc, int enable);
+int vhost_net_set_vring_enable(NetClientState *nc, int enable);
 
 uint64_t vhost_net_get_acked_features(VHostNetState *net);
 

meson.build

@@ -1285,6 +1285,10 @@ if not get_option('slirp').auto() or have_system
   endif
 endif
 
+enable_passt = get_option('passt') \
+  .require(host_os == 'linux', error_message: 'passt is supported only on Linux') \
+  .allowed()
+
 vde = not_found
 if not get_option('vde').auto() or have_system or have_tools
   vde = cc.find_library('vdeplug', has_headers: ['libvdeplug.h'],
@@ -2538,6 +2542,7 @@ if seccomp.found()
   config_host_data.set('CONFIG_SECCOMP_SYSRAWRC', seccomp_has_sysrawrc)
 endif
 config_host_data.set('CONFIG_PIXMAN', pixman.found())
+config_host_data.set('CONFIG_PASST', enable_passt)
 config_host_data.set('CONFIG_SLIRP', slirp.found())
 config_host_data.set('CONFIG_SNAPPY', snappy.found())
 config_host_data.set('CONFIG_SOLARIS', host_os == 'sunos')
@@ -4926,6 +4931,7 @@ if host_os == 'darwin'
   summary_info += {'vmnet.framework support': vmnet}
 endif
 summary_info += {'AF_XDP support':    libxdp}
+summary_info += {'passt support':     enable_passt}
 summary_info += {'slirp support':     slirp}
 summary_info += {'vde support':       vde}
 summary_info += {'netmap support':    have_netmap}

meson_options.txt

@@ -234,6 +234,8 @@ option('pixman', type : 'feature', value : 'auto',
        description: 'pixman support')
 option('slirp', type: 'feature', value: 'auto',
        description: 'libslirp user mode network backend support')
+option('passt', type: 'feature', value: 'auto',
+       description: 'passt network backend support')
 option('vde', type : 'feature', value : 'auto',
        description: 'vde network backend support')
 option('vmnet', type : 'feature', value : 'auto',

net/af-xdp.c

@@ -323,7 +323,7 @@ static int af_xdp_umem_create(AFXDPState *s, int sock_fd, Error **errp)
 
     s->pool = g_new(uint64_t, n_descs);
     /* Fill the pool in the opposite order, because it's a LIFO queue. */
-    for (i = n_descs; i >= 0; i--) {
+    for (i = n_descs - 1; i >= 0; i--) {
         s->pool[i] = i * XSK_UMEM__DEFAULT_FRAME_SIZE;
     }
     s->n_pool = n_descs;

net/clients.h

@@ -29,6 +29,10 @@
 int net_init_dump(const Netdev *netdev, const char *name,
                   NetClientState *peer, Error **errp);
 
+#ifdef CONFIG_PASST
+int net_init_passt(const Netdev *netdev, const char *name,
+                   NetClientState *peer, Error **errp);
+#endif
 #ifdef CONFIG_SLIRP
 int net_init_slirp(const Netdev *netdev, const char *name,
                    NetClientState *peer, Error **errp);

net/hub.c

@@ -285,6 +285,9 @@ void net_hub_check_clients(void)
             case NET_CLIENT_DRIVER_NIC:
                 has_nic = 1;
                 break;
+#ifdef CONFIG_PASST
+            case NET_CLIENT_DRIVER_PASST:
+#endif
             case NET_CLIENT_DRIVER_USER:
             case NET_CLIENT_DRIVER_TAP:
             case NET_CLIENT_DRIVER_SOCKET:

net/meson.build

@@ -1,6 +1,7 @@
 system_ss.add(files(
   'announce.c',
   'checksum.c',
+  'dgram.c',
   'dump.c',
   'eth.c',
   'filter-buffer.c',
@@ -12,7 +13,7 @@ system_ss.add(files(
   'queue.c',
   'socket.c',
   'stream.c',
-  'dgram.c',
+  'stream_data.c',
   'util.c',
 ))
 
@@ -33,6 +34,9 @@ system_ss.add(when: 'CONFIG_TCG', if_true: files('filter-replay.c'))
 if have_l2tpv3
   system_ss.add(files('l2tpv3.c'))
 endif
+if enable_passt
+  system_ss.add(files('passt.c'))
+endif
 system_ss.add(when: slirp, if_true: files('slirp.c'))
 system_ss.add(when: vde, if_true: files('vde.c'))
 if have_netmap

net/net.c

@@ -1248,6 +1248,9 @@ static int (* const net_client_init_fun[NET_CLIENT_DRIVER__MAX])(
     const char *name,
     NetClientState *peer, Error **errp) = {
         [NET_CLIENT_DRIVER_NIC]       = net_init_nic,
+#ifdef CONFIG_PASST
+        [NET_CLIENT_DRIVER_PASST]     = net_init_passt,
+#endif
 #ifdef CONFIG_SLIRP
         [NET_CLIENT_DRIVER_USER]      = net_init_slirp,
 #endif
@@ -1353,6 +1356,7 @@ void show_netdevs(void)
         "dgram",
         "hubport",
         "tap",
+        "passt",
 #ifdef CONFIG_SLIRP
         "user",
 #endif
@@ -1601,21 +1605,11 @@ void colo_notify_filters_event(int event, Error **errp)
     }
 }
 
-void qmp_set_link(const char *name, bool up, Error **errp)
+void net_client_set_link(NetClientState **ncs, int queues, bool up)
 {
-    NetClientState *ncs[MAX_QUEUE_NUM];
     NetClientState *nc;
-    int queues, i;
+    int i;
 
-    queues = qemu_find_net_clients_except(name, ncs,
-                                          NET_CLIENT_DRIVER__MAX,
-                                          MAX_QUEUE_NUM);
-
-    if (queues == 0) {
-        error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
-                  "Device '%s' not found", name);
-        return;
-    }
     nc = ncs[0];
 
     for (i = 0; i < queues; i++) {
@@ -1646,6 +1640,24 @@ void qmp_set_link(const char *name, bool up, Error **errp)
     }
 }
 
+void qmp_set_link(const char *name, bool up, Error **errp)
+{
+    NetClientState *ncs[MAX_QUEUE_NUM];
+    int queues;
+
+    queues = qemu_find_net_clients_except(name, ncs,
+                                          NET_CLIENT_DRIVER__MAX,
+                                          MAX_QUEUE_NUM);
+
+    if (queues == 0) {
+        error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
+                  "Device '%s' not found", name);
+        return;
+    }
+
+    net_client_set_link(ncs, queues, up);
+}
+
 static void net_vm_change_state_handler(void *opaque, bool running,
                                         RunState state)
 {