virtio-net: implement RSS configuration command

Optionally report RSS feature.
Handle RSS configuration command and keep RSS parameters
in virtio-net device context.

Signed-off-by: Yuri Benditovich <yuri.benditovich@daynix.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>

2 files changed, 161 insertions, 9 deletions

diff --git a/hw/net/trace-events b/hw/net/trace-events
index 26700dad99..e6875c4c0f 100644
--- a/hw/net/trace-events
+++ b/hw/net/trace-events
@@ -381,6 +381,9 @@ virtio_net_announce_notify(void) ""
 virtio_net_announce_timer(int round) "%d"
 virtio_net_handle_announce(int round) "%d"
 virtio_net_post_load_device(void)
+virtio_net_rss_disable(void)
+virtio_net_rss_error(const char *msg, uint32_t value) "%s, value 0x%08x"
+virtio_net_rss_enable(uint32_t p1, uint16_t p2, uint8_t p3) "hashes 0x%x, table of %d, key of %d"
 
 # tulip.c
 tulip_reg_write(uint64_t addr, const char *name, int size, uint64_t val) "addr 0x%02"PRIx64" (%s) size %d value 0x%08"PRIx64
diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index b7f3d1b2eb..e803b0a26f 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -77,6 +77,16 @@
    tso/gso/gro 'off'. */
 #define VIRTIO_NET_RSC_DEFAULT_INTERVAL 300000
 
+#define VIRTIO_NET_RSS_SUPPORTED_HASHES (VIRTIO_NET_RSS_HASH_TYPE_IPv4 | \
+                                         VIRTIO_NET_RSS_HASH_TYPE_TCPv4 | \
+                                         VIRTIO_NET_RSS_HASH_TYPE_UDPv4 | \
+                                         VIRTIO_NET_RSS_HASH_TYPE_IPv6 | \
+                                         VIRTIO_NET_RSS_HASH_TYPE_TCPv6 | \
+                                         VIRTIO_NET_RSS_HASH_TYPE_UDPv6 | \
+                                         VIRTIO_NET_RSS_HASH_TYPE_IP_EX | \
+                                         VIRTIO_NET_RSS_HASH_TYPE_TCP_EX | \
+                                         VIRTIO_NET_RSS_HASH_TYPE_UDP_EX)
+
 /* temporary until standard header include it */
 #if !defined(VIRTIO_NET_HDR_F_RSC_INFO)
 
@@ -108,6 +118,8 @@ static VirtIOFeature feature_sizes[] = {
      .end = endof(struct virtio_net_config, mtu)},
     {.flags = 1ULL << VIRTIO_NET_F_SPEED_DUPLEX,
      .end = endof(struct virtio_net_config, duplex)},
+    {.flags = 1ULL << VIRTIO_NET_F_RSS,
+     .end = endof(struct virtio_net_config, supported_hash_types)},
     {}
 };
 
@@ -138,6 +150,11 @@ static void virtio_net_get_config(VirtIODevice *vdev, uint8_t *config)
     memcpy(netcfg.mac, n->mac, ETH_ALEN);
     virtio_stl_p(vdev, &netcfg.speed, n->net_conf.speed);
     netcfg.duplex = n->net_conf.duplex;
+    netcfg.rss_max_key_size = VIRTIO_NET_RSS_MAX_KEY_SIZE;
+    virtio_stw_p(vdev, &netcfg.rss_max_indirection_table_length,
+                 VIRTIO_NET_RSS_MAX_TABLE_LEN);
+    virtio_stl_p(vdev, &netcfg.supported_hash_types,
+                 VIRTIO_NET_RSS_SUPPORTED_HASHES);
     memcpy(config, &netcfg, n->config_size);
 }
 
@@ -701,6 +718,7 @@ static uint64_t virtio_net_get_features(VirtIODevice *vdev, uint64_t features,
         return features;
     }
 
+    virtio_clear_feature(&features, VIRTIO_NET_F_RSS);
     features = vhost_net_get_features(get_vhost_net(nc->peer), features);
     vdev->backend_features = features;
 
@@ -860,6 +878,7 @@ static void virtio_net_set_features(VirtIODevice *vdev, uint64_t features)
     }
 
     virtio_net_set_multiqueue(n,
+                              virtio_has_feature(features, VIRTIO_NET_F_RSS) ||
                               virtio_has_feature(features, VIRTIO_NET_F_MQ));
 
     virtio_net_set_mrg_rx_bufs(n,
@@ -1136,25 +1155,152 @@ static int virtio_net_handle_announce(VirtIONet *n, uint8_t cmd,
     }
 }
 
+static void virtio_net_disable_rss(VirtIONet *n)
+{
+    if (n->rss_data.enabled) {
+        trace_virtio_net_rss_disable();
+    }
+    n->rss_data.enabled = false;
+}
+
+static uint16_t virtio_net_handle_rss(VirtIONet *n,
+                                      struct iovec *iov, unsigned int iov_cnt)
+{
+    VirtIODevice *vdev = VIRTIO_DEVICE(n);
+    struct virtio_net_rss_config cfg;
+    size_t s, offset = 0, size_get;
+    uint16_t queues, i;
+    struct {
+        uint16_t us;
+        uint8_t b;
+    } QEMU_PACKED temp;
+    const char *err_msg = "";
+    uint32_t err_value = 0;
+
+    if (!virtio_vdev_has_feature(vdev, VIRTIO_NET_F_RSS)) {
+        err_msg = "RSS is not negotiated";
+        goto error;
+    }
+    size_get = offsetof(struct virtio_net_rss_config, indirection_table);
+    s = iov_to_buf(iov, iov_cnt, offset, &cfg, size_get);
+    if (s != size_get) {
+        err_msg = "Short command buffer";
+        err_value = (uint32_t)s;
+        goto error;
+    }
+    n->rss_data.hash_types = virtio_ldl_p(vdev, &cfg.hash_types);
+    n->rss_data.indirections_len =
+        virtio_lduw_p(vdev, &cfg.indirection_table_mask);
+    n->rss_data.indirections_len++;
+    if (!is_power_of_2(n->rss_data.indirections_len)) {
+        err_msg = "Invalid size of indirection table";
+        err_value = n->rss_data.indirections_len;
+        goto error;
+    }
+    if (n->rss_data.indirections_len > VIRTIO_NET_RSS_MAX_TABLE_LEN) {
+        err_msg = "Too large indirection table";
+        err_value = n->rss_data.indirections_len;
+        goto error;
+    }
+    n->rss_data.default_queue =
+        virtio_lduw_p(vdev, &cfg.unclassified_queue);
+    if (n->rss_data.default_queue >= n->max_queues) {
+        err_msg = "Invalid default queue";
+        err_value = n->rss_data.default_queue;
+        goto error;
+    }
+    offset += size_get;
+    size_get = sizeof(uint16_t) * n->rss_data.indirections_len;
+    g_free(n->rss_data.indirections_table);
+    n->rss_data.indirections_table = g_malloc(size_get);
+    if (!n->rss_data.indirections_table) {
+        err_msg = "Can't allocate indirections table";
+        err_value = n->rss_data.indirections_len;
+        goto error;
+    }
+    s = iov_to_buf(iov, iov_cnt, offset,
+                   n->rss_data.indirections_table, size_get);
+    if (s != size_get) {
+        err_msg = "Short indirection table buffer";
+        err_value = (uint32_t)s;
+        goto error;
+    }
+    for (i = 0; i < n->rss_data.indirections_len; ++i) {
+        uint16_t val = n->rss_data.indirections_table[i];
+        n->rss_data.indirections_table[i] = virtio_lduw_p(vdev, &val);
+    }
+    offset += size_get;
+    size_get = sizeof(temp);
+    s = iov_to_buf(iov, iov_cnt, offset, &temp, size_get);
+    if (s != size_get) {
+        err_msg = "Can't get queues";
+        err_value = (uint32_t)s;
+        goto error;
+    }
+    queues = virtio_lduw_p(vdev, &temp.us);
+    if (queues == 0 || queues > n->max_queues) {
+        err_msg = "Invalid number of queues";
+        err_value = queues;
+        goto error;
+    }
+    if (temp.b > VIRTIO_NET_RSS_MAX_KEY_SIZE) {
+        err_msg = "Invalid key size";
+        err_value = temp.b;
+        goto error;
+    }
+    if (!temp.b && n->rss_data.hash_types) {
+        err_msg = "No key provided";
+        err_value = 0;
+        goto error;
+    }
+    if (!temp.b && !n->rss_data.hash_types) {
+        virtio_net_disable_rss(n);
+        return queues;
+    }
+    offset += size_get;
+    size_get = temp.b;
+    s = iov_to_buf(iov, iov_cnt, offset, n->rss_data.key, size_get);
+    if (s != size_get) {
+        err_msg = "Can get key buffer";
+        err_value = (uint32_t)s;
+        goto error;
+    }
+    n->rss_data.enabled = true;
+    trace_virtio_net_rss_enable(n->rss_data.hash_types,
+                                n->rss_data.indirections_len,
+                                temp.b);
+    return queues;
+error:
+    trace_virtio_net_rss_error(err_msg, err_value);
+    virtio_net_disable_rss(n);
+    return 0;
+}
+
 static int virtio_net_handle_mq(VirtIONet *n, uint8_t cmd,
                                 struct iovec *iov, unsigned int iov_cnt)
 {
     VirtIODevice *vdev = VIRTIO_DEVICE(n);
-    struct virtio_net_ctrl_mq mq;
-    size_t s;
     uint16_t queues;
 
-    s = iov_to_buf(iov, iov_cnt, 0, &mq, sizeof(mq));
-    if (s != sizeof(mq)) {
-        return VIRTIO_NET_ERR;
-    }
+    virtio_net_disable_rss(n);
+    if (cmd == VIRTIO_NET_CTRL_MQ_RSS_CONFIG) {
+        queues = virtio_net_handle_rss(n, iov, iov_cnt);
+    } else if (cmd == VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET) {
+        struct virtio_net_ctrl_mq mq;
+        size_t s;
+        if (!virtio_vdev_has_feature(vdev, VIRTIO_NET_F_MQ)) {
+            return VIRTIO_NET_ERR;
+        }
+        s = iov_to_buf(iov, iov_cnt, 0, &mq, sizeof(mq));
+        if (s != sizeof(mq)) {
+            return VIRTIO_NET_ERR;
+        }
+        queues = virtio_lduw_p(vdev, &mq.virtqueue_pairs);
 
-    if (cmd != VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET) {
+    } else {
         return VIRTIO_NET_ERR;
     }
 
-    queues = virtio_lduw_p(vdev, &mq.virtqueue_pairs);
-
     if (queues < VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN ||
         queues > VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX ||
         queues > n->max_queues ||
@@ -3111,6 +3257,7 @@ static void virtio_net_device_unrealize(DeviceState *dev)
     g_free(n->vqs);
     qemu_del_nic(n->nic);
     virtio_net_rsc_cleanup(n);
+    g_free(n->rss_data.indirections_table);
     virtio_cleanup(vdev);
 }
 
@@ -3212,6 +3359,8 @@ static Property virtio_net_properties[] = {
     DEFINE_PROP_BIT64("ctrl_guest_offloads", VirtIONet, host_features,
                     VIRTIO_NET_F_CTRL_GUEST_OFFLOADS, true),
     DEFINE_PROP_BIT64("mq", VirtIONet, host_features, VIRTIO_NET_F_MQ, false),
+    DEFINE_PROP_BIT64("rss", VirtIONet, host_features,
+                    VIRTIO_NET_F_RSS, false),
     DEFINE_PROP_BIT64("guest_rsc_ext", VirtIONet, host_features,
                     VIRTIO_NET_F_RSC_EXT, false),
     DEFINE_PROP_UINT32("rsc_interval", VirtIONet, rsc_timeout,