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>

4 files changed, 51 insertions, 158 deletions

diff --git a/hw/net/vhost_net-stub.c b/hw/net/vhost_net-stub.c
index 72df6d7..7d49f82 100644
--- a/hw/net/vhost_net-stub.c
+++ b/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;
 }
diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c
index 891f235..540492b 100644
--- a/hw/net/vhost_net.c
+++ b/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;
diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index eb93607..00df5fd 100644
--- a/hw/net/virtio-net.c
+++ b/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;
 }
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index 82a285a..7e38b1c 100644
--- a/hw/virtio/virtio.c
+++ b/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) {