sfc: Support ARFS for IPv6 flows

Extend efx_filter_rfs() to map TCP/IPv6 and UDP/IPv6 flows into
efx_filter_spec.  These are only supported on EF10; on Falcon and
Siena they will be rejected by efx_farch_filter_from_gen_spec().

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>

1 files changed, 62 insertions, 28 deletions

diff --git a/drivers/net/ethernet/sfc/rx.c b/drivers/net/ethernet/sfc/rx.c
index 4a596725023f..8f09e686fc23 100644
--- a/drivers/net/ethernet/sfc/rx.c
+++ b/drivers/net/ethernet/sfc/rx.c
@@ -12,6 +12,7 @@
 #include <linux/in.h>
 #include <linux/slab.h>
 #include <linux/ip.h>
+#include <linux/ipv6.h>
 #include <linux/tcp.h>
 #include <linux/udp.h>
 #include <linux/prefetch.h>
@@ -818,44 +819,70 @@ int efx_filter_rfs(struct net_device *net_dev, const struct sk_buff *skb,
         struct efx_nic *efx = netdev_priv(net_dev);
         struct efx_channel *channel;
         struct efx_filter_spec spec;
-        const struct iphdr *ip;
         const __be16 *ports;
+        __be16 ether_type;
         int nhoff;
         int rc;
 
-        nhoff = skb_network_offset(skb);
+        /* The core RPS/RFS code has already parsed and validated
+         * VLAN, IP and transport headers.  We assume they are in the
+         * header area.
+         */
 
         if (skb->protocol == htons(ETH_P_8021Q)) {
-                EFX_BUG_ON_PARANOID(skb_headlen(skb) <
-                                    nhoff + sizeof(struct vlan_hdr));
-                if (((const struct vlan_hdr *)skb->data + nhoff)->
-                    h_vlan_encapsulated_proto != htons(ETH_P_IP))
-                        return -EPROTONOSUPPORT;
+                const struct vlan_hdr *vh =
+                        (const struct vlan_hdr *)skb->data;
 
-                /* This is IP over 802.1q VLAN.  We can't filter on the
-                 * IP 5-tuple and the vlan together, so just strip the
-                 * vlan header and filter on the IP part.
+                /* We can't filter on the IP 5-tuple and the vlan
+                 * together, so just strip the vlan header and filter
+                 * on the IP part.
                  */
-                nhoff += sizeof(struct vlan_hdr);
-        } else if (skb->protocol != htons(ETH_P_IP)) {
-                return -EPROTONOSUPPORT;
+                EFX_BUG_ON_PARANOID(skb_headlen(skb) < sizeof(*vh));
+                ether_type = vh->h_vlan_encapsulated_proto;
+                nhoff = sizeof(struct vlan_hdr);
+        } else {
+                ether_type = skb->protocol;
+                nhoff = 0;
         }
 
-        /* RFS must validate the IP header length before calling us */
-        EFX_BUG_ON_PARANOID(skb_headlen(skb) < nhoff + sizeof(*ip));
-        ip = (const struct iphdr *)(skb->data + nhoff);
-        if (ip_is_fragment(ip))
+        if (ether_type != htons(ETH_P_IP) && ether_type != htons(ETH_P_IPV6))
                 return -EPROTONOSUPPORT;
-        EFX_BUG_ON_PARANOID(skb_headlen(skb) < nhoff + 4 * ip->ihl + 4);
-        ports = (const __be16 *)(skb->data + nhoff + 4 * ip->ihl);
 
         efx_filter_init_rx(&spec, EFX_FILTER_PRI_HINT,
                            efx->rx_scatter ? EFX_FILTER_FLAG_RX_SCATTER : 0,
                            rxq_index);
-        rc = efx_filter_set_ipv4_full(&spec, ip->protocol,
-                                      ip->daddr, ports[1], ip->saddr, ports[0]);
-        if (rc)
-                return rc;
+        spec.match_flags =
+                EFX_FILTER_MATCH_ETHER_TYPE | EFX_FILTER_MATCH_IP_PROTO |
+                EFX_FILTER_MATCH_LOC_HOST | EFX_FILTER_MATCH_LOC_PORT |
+                EFX_FILTER_MATCH_REM_HOST | EFX_FILTER_MATCH_REM_PORT;
+        spec.ether_type = ether_type;
+
+        if (ether_type == htons(ETH_P_IP)) {
+                const struct iphdr *ip =
+                        (const struct iphdr *)(skb->data + nhoff);
+
+                EFX_BUG_ON_PARANOID(skb_headlen(skb) < nhoff + sizeof(*ip));
+                if (ip_is_fragment(ip))
+                        return -EPROTONOSUPPORT;
+                spec.ip_proto = ip->protocol;
+                spec.rem_host[0] = ip->saddr;
+                spec.loc_host[0] = ip->daddr;
+                EFX_BUG_ON_PARANOID(skb_headlen(skb) < nhoff + 4 * ip->ihl + 4);
+                ports = (const __be16 *)(skb->data + nhoff + 4 * ip->ihl);
+        } else {
+                const struct ipv6hdr *ip6 =
+                        (const struct ipv6hdr *)(skb->data + nhoff);
+
+                EFX_BUG_ON_PARANOID(skb_headlen(skb) <
+                                    nhoff + sizeof(*ip6) + 4);
+                spec.ip_proto = ip6->nexthdr;
+                memcpy(spec.rem_host, &ip6->saddr, sizeof(ip6->saddr));
+                memcpy(spec.loc_host, &ip6->daddr, sizeof(ip6->daddr));
+                ports = (const __be16 *)(ip6 + 1);
+        }
+
+        spec.rem_port = ports[0];
+        spec.loc_port = ports[1];
 
         rc = efx->type->filter_rfs_insert(efx, &spec);
         if (rc < 0)
@@ -866,11 +893,18 @@ int efx_filter_rfs(struct net_device *net_dev, const struct sk_buff *skb,
         channel = efx_get_channel(efx, skb_get_rx_queue(skb));
         ++channel->rfs_filters_added;
 
-        netif_info(efx, rx_status, efx->net_dev,
-                   "steering %s %pI4:%u:%pI4:%u to queue %u [flow %u filter %d]\n",
-                   (ip->protocol == IPPROTO_TCP) ? "TCP" : "UDP",
-                   &ip->saddr, ntohs(ports[0]), &ip->daddr, ntohs(ports[1]),
-                   rxq_index, flow_id, rc);
+        if (ether_type == htons(ETH_P_IP))
+                netif_info(efx, rx_status, efx->net_dev,
+                           "steering %s %pI4:%u:%pI4:%u to queue %u [flow %u filter %d]\n",
+                           (spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP",
+                           spec.rem_host, ntohs(ports[0]), spec.loc_host,
+                           ntohs(ports[1]), rxq_index, flow_id, rc);
+        else
+                netif_info(efx, rx_status, efx->net_dev,
+                           "steering %s [%pI6]:%u:[%pI6]:%u to queue %u [flow %u filter %d]\n",
+                           (spec.ip_proto == IPPROTO_TCP) ? "TCP" : "UDP",
+                           spec.rem_host, ntohs(ports[0]), spec.loc_host,
+                           ntohs(ports[1]), rxq_index, flow_id, rc);
 
         return rc;
 }