[PATCH v2 3/4] drivers/net/virtio_net: Added RSS hash report.

From: Andrew Melnychenko
Date: Mon Jan 17 2022 - 03:00:49 EST


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 <andrew@xxxxxxxxxx>
---
drivers/net/virtio_net.c | 58 ++++++++++++++++++++++++++++++++--------
1 file changed, 47 insertions(+), 11 deletions(-)

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 9aae11cb568e..2c61f96ce3e6 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;
@@ -420,7 +421,9 @@ static struct sk_buff *page_to_skb(struct virtnet_info *vi,
hdr_p = p;

hdr_len = vi->hdr_len;
- if (vi->mergeable_rx_bufs)
+ if (vi->has_rss_hash_report)
+ hdr_padded_len = sizeof(struct virtio_net_hdr_v1_hash);
+ else if (vi->mergeable_rx_bufs)
hdr_padded_len = sizeof(*hdr);
else
hdr_padded_len = sizeof(struct padded_vnet_hdr);
@@ -1156,6 +1159,8 @@ 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 +1187,29 @@ 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 +2260,8 @@ 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 +3259,8 @@ 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;
}
@@ -3365,16 +3396,18 @@ 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));
+ rss_max_indirection_table_length));
vi->rss_key_size =
virtio_cread8(vdev, offsetof(struct virtio_net_config, rss_max_key_size));
- }
-
- if (vi->has_rss) {
vi->rss_hash_types_supported =
virtio_cread32(vdev, offsetof(struct virtio_net_config, supported_hash_types));
vi->rss_hash_types_supported &=
@@ -3384,8 +3417,11 @@ 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);
@@ -3452,7 +3488,7 @@ 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);
@@ -3587,7 +3623,7 @@ 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