Re: [PATCH v3 3/4] drivers/net/virtio_net: Added RSS hash report.

Added features for RSS hash report.
If hash is provided - it sets to skb.
Added checks if rss and/or hash are enabled together.

Signed-off-by: Andrew Melnychenko <redacted>
---
 drivers/net/virtio_net.c | 51 ++++++++++++++++++++++++++++++++++------
 1 file changed, 44 insertions(+), 7 deletions(-)

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 495aed524e33..543da2fbdd2d 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c

@@ -227,6 +227,7 @@ struct virtnet_info {

        /* Host supports rss and/or hash report */
        bool has_rss;
+       bool has_rss_hash_report;
        u8 rss_key_size;
        u16 rss_indir_table_size;
        u32 rss_hash_types_supported;

@@ -421,7 +422,7 @@ static struct sk_buff *page_to_skb(struct virtnet_info *vi,

        hdr_len = vi->hdr_len;
        if (vi->mergeable_rx_bufs)
-               hdr_padded_len = sizeof(*hdr);
+               hdr_padded_len = hdr_len;

        else
                hdr_padded_len = sizeof(struct padded_vnet_hdr);

@@ -1156,6 +1157,8 @@ static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq,
        struct net_device *dev = vi->dev;
        struct sk_buff *skb;
        struct virtio_net_hdr_mrg_rxbuf *hdr;
+       struct virtio_net_hdr_v1_hash *hdr_hash;
+       enum pkt_hash_types rss_hash_type;

        if (unlikely(len < vi->hdr_len + ETH_HLEN)) {
                pr_debug("%s: short packet %i\n", dev->name, len);

@@ -1182,6 +1185,29 @@ static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq,
                return;

        hdr = skb_vnet_hdr(skb);
+       if (dev->features & NETIF_F_RXHASH && vi->has_rss_hash_report) {

+               hdr_hash = (struct virtio_net_hdr_v1_hash *)(hdr);
+
+               switch (hdr_hash->hash_report) {
+               case VIRTIO_NET_HASH_REPORT_TCPv4:
+               case VIRTIO_NET_HASH_REPORT_UDPv4:
+               case VIRTIO_NET_HASH_REPORT_TCPv6:
+               case VIRTIO_NET_HASH_REPORT_UDPv6:
+               case VIRTIO_NET_HASH_REPORT_TCPv6_EX:
+               case VIRTIO_NET_HASH_REPORT_UDPv6_EX:
+                       rss_hash_type = PKT_HASH_TYPE_L4;
+                       break;
+               case VIRTIO_NET_HASH_REPORT_IPv4:
+               case VIRTIO_NET_HASH_REPORT_IPv6:
+               case VIRTIO_NET_HASH_REPORT_IPv6_EX:
+                       rss_hash_type = PKT_HASH_TYPE_L3;
+                       break;
+               case VIRTIO_NET_HASH_REPORT_NONE:
+               default:
+                       rss_hash_type = PKT_HASH_TYPE_NONE;
+               }
+               skb_set_hash(skb, hdr_hash->hash_value, rss_hash_type);
+       }

        if (hdr->hdr.flags & VIRTIO_NET_HDR_F_DATA_VALID)
                skb->ip_summed = CHECKSUM_UNNECESSARY;

@@ -2232,7 +2258,8 @@ static bool virtnet_commit_rss_command(struct virtnet_info *vi)
        sg_set_buf(&sgs[3], vi->ctrl->rss.key, sg_buf_size);

        if (!virtnet_send_command(vi, VIRTIO_NET_CTRL_MQ,
-                                 VIRTIO_NET_CTRL_MQ_RSS_CONFIG, sgs)) {
+                                 vi->has_rss ? VIRTIO_NET_CTRL_MQ_RSS_CONFIG
+                                 : VIRTIO_NET_CTRL_MQ_HASH_CONFIG, sgs)) {
                dev_warn(&dev->dev, "VIRTIONET issue with committing RSS sgs\n");
                return false;
        }

@@ -3230,6 +3257,8 @@ static bool virtnet_validate_features(struct virtio_device *vdev)
             VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_CTRL_MAC_ADDR,
                             "VIRTIO_NET_F_CTRL_VQ") ||
             VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_RSS,
+                            "VIRTIO_NET_F_CTRL_VQ") ||
+            VIRTNET_FAIL_ON(vdev, VIRTIO_NET_F_HASH_REPORT,
                             "VIRTIO_NET_F_CTRL_VQ"))) {
                return false;
        }

@@ -3365,8 +3394,13 @@ static int virtnet_probe(struct virtio_device *vdev)
        if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF))
                vi->mergeable_rx_bufs = true;

-       if (virtio_has_feature(vdev, VIRTIO_NET_F_RSS)) {
+       if (virtio_has_feature(vdev, VIRTIO_NET_F_HASH_REPORT))
+               vi->has_rss_hash_report = true;
+
+       if (virtio_has_feature(vdev, VIRTIO_NET_F_RSS))
                vi->has_rss = true;
+
+       if (vi->has_rss || vi->has_rss_hash_report) {
                vi->rss_indir_table_size =
                        virtio_cread16(vdev, offsetof(struct virtio_net_config,

                                rss_max_indirection_table_length));

@@ -3382,8 +3416,11 @@ static int virtnet_probe(struct virtio_device *vdev)

                dev->hw_features |= NETIF_F_RXHASH;
        }
-       if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF) ||
-           virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
+
+       if (vi->has_rss_hash_report)
+               vi->hdr_len = sizeof(struct virtio_net_hdr_v1_hash);
+       else if (virtio_has_feature(vdev, VIRTIO_NET_F_MRG_RXBUF) ||
+                virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
                vi->hdr_len = sizeof(struct virtio_net_hdr_mrg_rxbuf);
        else
                vi->hdr_len = sizeof(struct virtio_net_hdr);

@@ -3450,7 +3487,7 @@ static int virtnet_probe(struct virtio_device *vdev)
                }
        }

-       if (vi->has_rss)
+       if (vi->has_rss || vi->has_rss_hash_report)
                virtnet_init_default_rss(vi);

        err = register_netdev(dev);

@@ -3585,7 +3622,7 @@ static struct virtio_device_id id_table[] = {
        VIRTIO_NET_F_CTRL_MAC_ADDR, \
        VIRTIO_NET_F_MTU, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS, \
        VIRTIO_NET_F_SPEED_DUPLEX, VIRTIO_NET_F_STANDBY, \
-       VIRTIO_NET_F_RSS
+       VIRTIO_NET_F_RSS, VIRTIO_NET_F_HASH_REPORT

 static unsigned int features[] = {
        VIRTNET_FEATURES,
--

2.34.1